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Sample records for yield efficiency leaf

  1. Effect of different transplanting leaf age on rice yield, nitrogen utilization efficiency and fate of 15N-fertilizer

    International Nuclear Information System (INIS)

    Fan Hongzhu; Lu Shihua; Zeng Xiangzhong

    2010-01-01

    Field experiments were conducted to study rice yield, N uptake and fate by using 15 N-urea at transplanting leaf age of 2-, 4-and 6-leaf, respectively. The results showed that rice yield significantly decreased with delay of transplanting leaf age, and 15 N-fertilizer uptake by grain and straw of rice, nitrogen utilization and residue also decreased, but loss of 15 N-fertilizer increased. Under different transplanting leaf age, N absorption by rice mainly came from the soil. Almost 1/3 of total N was supplied by fertilizer, and 2/3 came from soil. The efficiency of fertilizer was 20.8% ∼ 25.7%, 15 N-fertilizer residue ratio was 17.9% ∼ 32.2%, and 15 N-fertilizer loss was 42.1% ∼ 61.3%. 15 N-fertilizer residue mainly distributed in 0 ∼ 20 cm top soil under different treatments. The results indicated that transplanting young leaf age could increase rice yield and nitrogen utilization efficiency, and decrease loss of nitrogen fertilizer and pollution level on environment. (authors)

  2. Long-term Low Radiation Decreases Leaf Photosynthesis, Photochemical Efficiency and Grain Yield in Winter Wheat

    DEFF Research Database (Denmark)

    Mu, H; Jiang, D; Wollenweber, Bernd

    2010-01-01

    the impact of low radiation on crop growth, photosynthesis and yield. Grain yield losses and leaf area index (LAI) reduction were less than the reduction in solar radiation under both shading treatment in both cultivars. Compared with the control (S0), grain yield only reduced 6.4 % and 9.9 % under 22.......0-22.9 % (S1) and 29.5-49.6 % (S2), which was consistent with the reduction in radiation. The reduction in LAI was partially compensated by increases in the fraction of the top and bottom leaf area to the total leaf area, which facilitated to intercept more solar radiation by the canopy. The decrease......Low radiation reduces wheat grain yield in tree-crop intercropping systems in the major wheat planting area of China. Here, two winter wheat (Triticum aestivum L) cultivars, Yangmai 158 (shading tolerant) and Yangmai 11 (shading sensitive), were shaded from jointing to maturity to evaluate...

  3. Leaf transpiration efficiency in corn varieties grown at elevated carbon dioxide

    Science.gov (United States)

    Higher leaf transpiration efficiency (TE) without lower photosynthesis has been identified in some varieties of corn in field tests, and could be a useful trait to improve yield under dry conditions without sacrificing yield under favorable conditions. However, because the carbon dioxide concentrat...

  4. Accounting for the decrease of photosystem photochemical efficiency with increasing irradiance to estimate quantum yield of leaf photosynthesis.

    Science.gov (United States)

    Yin, Xinyou; Belay, Daniel W; van der Putten, Peter E L; Struik, Paul C

    2014-12-01

    Maximum quantum yield for leaf CO2 assimilation under limiting light conditions (Φ CO2LL) is commonly estimated as the slope of the linear regression of net photosynthetic rate against absorbed irradiance over a range of low-irradiance conditions. Methodological errors associated with this estimation have often been attributed either to light absorptance by non-photosynthetic pigments or to some data points being beyond the linear range of the irradiance response, both causing an underestimation of Φ CO2LL. We demonstrate here that a decrease in photosystem (PS) photochemical efficiency with increasing irradiance, even at very low levels, is another source of error that causes a systematic underestimation of Φ CO2LL. A model method accounting for this error was developed, and was used to estimate Φ CO2LL from simultaneous measurements of gas exchange and chlorophyll fluorescence on leaves using various combinations of species, CO2, O2, or leaf temperature levels. The conventional linear regression method under-estimated Φ CO2LL by ca. 10-15%. Differences in the estimated Φ CO2LL among measurement conditions were generally accounted for by different levels of photorespiration as described by the Farquhar-von Caemmerer-Berry model. However, our data revealed that the temperature dependence of PSII photochemical efficiency under low light was an additional factor that should be accounted for in the model.

  5. Effects of split nitrogen fertilization on post-anthesis photoassimilates, nitrogen use efficiency and grain yield in malting barley

    DEFF Research Database (Denmark)

    Cai, Jian; Jiang, Dong; Liu, Fulai

    2011-01-01

    photosynthesis after anthesis, dry matter accumulation and assimilates remobilization, nitrogen use efficiency and grain yield to fraction of topdressed nitrogen treatments were investigated in malting barley. Net photosynthetic rate of the penultimate leaf, leaf area index and light extinction coefficient...... assimilation rate and nitrogen use efficiency resulting in higher grain yields and proper grain protein content in malting barley.......Split nitrogen applications are widely adopted to improve grain yield and enhance nitrogen use effective in crops. In a twoyear field experiment at two eco-sites, five fractions of topdressed nitrogen of 0%, 20%, 30%, 40% and 50% were implemented. Responses of radiation interception and leaf...

  6. Spatial-temporal variability of leaf chlorophyll and its relationship with cocoa yield

    Directory of Open Access Journals (Sweden)

    Caique C. Medauar

    Full Text Available ABSTRACT The objective of this study was to evaluate the spatial-temporal variability of leaf chlorophyll index and its relationship with cocoa yield. The experiment was carried out in an experimental area of cocoa production located in Ilhéus, Bahia State, Brazil. Leaf chlorophyll content was measured in September, October, January, February, March and April in the 2014/2015 season, at each sampling point of a regular grid by using a portable chlorophyll meter. Under the same conditions, yield was evaluated and the data were submitted to descriptive statistics and a linear correlation study. Geostatistical analysis was used to determine and quantify the spatial and temporal variability of leaf chlorophyll index and yield. Leaf chlorophyll index varied over the period evaluated, but the months of February, March and April showed no spatial dependence in the study area, indicating absence of temporal stability. Cocoa monthly yield, except in January, presented high spatial variability. Under the conditions of this study, it was not possible to establish a relationship between leaf chlorophyll index and cocoa yield.

  7. Wind increases leaf water use efficiency.

    Science.gov (United States)

    Schymanski, Stanislaus J; Or, Dani

    2016-07-01

    A widespread perception is that, with increasing wind speed, transpiration from plant leaves increases. However, evidence suggests that increasing wind speed enhances carbon dioxide (CO2 ) uptake while reducing transpiration because of more efficient convective cooling (under high solar radiation loads). We provide theoretical and experimental evidence that leaf water use efficiency (WUE, carbon uptake per water transpired) commonly increases with increasing wind speed, thus improving plants' ability to conserve water during photosynthesis. Our leaf-scale analysis suggests that the observed global decrease in near-surface wind speeds could have reduced WUE at a magnitude similar to the increase in WUE attributed to global rise in atmospheric CO2 concentrations. However, there is indication that the effect of long-term trends in wind speed on leaf gas exchange may be compensated for by the concurrent reduction in mean leaf sizes. These unintuitive feedbacks between wind, leaf size and water use efficiency call for re-evaluation of the role of wind in plant water relations and potential re-interpretation of temporal and geographic trends in leaf sizes. © 2015 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

  8. Effect of Puccinia silphii on Yield Components and Leaf Physiology in Silphium integrifolium: Lessons for the Domestication of a Perennial Oilseed Crop

    Directory of Open Access Journals (Sweden)

    M. Kathryn Turner

    2018-03-01

    Full Text Available New crops with greater capacity for delivering ecosystem services are needed to increase agricultural sustainability. However, even in these crops, seed yield is usually the main criteria for grain domestication. This focus on yield can cause unintended structural and functional changes. Leaves of selected plants tend to be more vulnerable to infection, which can reduce performance, assimilates, and ultimately yield. Our objectives were to determine the impact of rust (caused by Puccinia silphii on yield and leaf function in selected Silphium integrifolium (Asteraceae plants. We tested the effect of a fungicide treatment on rust severity and yield, compared the rust infection of individuals in a population selected for yield, and related this to chemical changes at the leaf level. We also estimated heritability for rust resistance. We found that productivity indicators (head number and weight, leaf weight and leaf processes (photosynthetic capacity, water use efficiency were reduced when silphium leaves and stems were more heavily infected by P. silphii. Leaf resin content increased when susceptible plants were infected. Fungicide treatments were effective at reducing rust infection severity, but were ineffective at preventing yield losses. We propose that disease resistance should be included early in the selection process of new perennial crops.

  9. Enhancement of Biogas Yield of Poplar Leaf by High-Solid Codigestion with Swine Manure.

    Science.gov (United States)

    Wangliang, Li; Zhikai, Zhang; Guangwen, Xu

    2016-05-01

    The aim of this work was to examine the improvement of anaerobic biodegradability of organic fractions of poplar leaf from codigestion with swine manure (SM), thus biogas yield and energy recovery. When poplar leaf was used as a sole substrate, the cumulative biogas yield was low, about 163 mL (g volatile solid (VS))(-1) after 45 days of digestion with a substrate/inoculum ratio of 2.5 and a total solid (TS) of 22 %. Under the same condition, the cumulative biogas yield of poplar leaf reached 321 mL (g VS)(-1) when SM/poplar leaf ratio was 2:5 (based on VS). The SM/poplar leaf ratio can determine C/N ratio of the cosubstrate and thus has significant influence on biogas yield. When the SM/poplar leaf ratio was 2:5, C/N ratio was calculated to be 27.02, and the biogas yield in 45 days of digestion was the highest. The semi-continuous digestion of poplar leaf was carried out with the organic loading rate of 1.25 and 1.88 g VS day(-1). The average daily biogas yield was 230.2 mL (g VS)(-1) and 208.4 mL (g VS)(-1). The composition analysis revealed that cellulose and hemicellulose contributed to the biogas production.

  10. Simulation Models of Leaf Area Index and Yield for Cotton Grown with Different Soil Conditioners.

    Directory of Open Access Journals (Sweden)

    Lijun Su

    Full Text Available Simulation models of leaf area index (LAI and yield for cotton can provide a theoretical foundation for predicting future variations in yield. This paper analyses the increase in LAI and the relationships between LAI, dry matter, and yield for cotton under three soil conditioners near Korla, Xinjiang, China. Dynamic changes in cotton LAI were evaluated using modified logistic, Gaussian, modified Gaussian, log normal, and cubic polynomial models. Universal models for simulating the relative leaf area index (RLAI were established in which the application rate of soil conditioner was used to estimate the maximum LAI (LAIm. In addition, the relationships between LAIm and dry matter mass, yield, and the harvest index were investigated, and a simulation model for yield is proposed. A feasibility analysis of the models indicated that the cubic polynomial and Gaussian models were less accurate than the other three models for simulating increases in RLAI. Despite significant differences in LAIs under the type and amount of soil conditioner applied, LAIm could be described by aboveground dry matter using Michaelis-Menten kinetics. Moreover, the simulation model for cotton yield based on LAIm and the harvest index presented in this work provided important theoretical insights for improving water use efficiency in cotton cultivation and for identifying optimal application rates of soil conditioners.

  11. Leaf Senescence, Root Morphology, and Seed Yield of Winter Oilseed Rape (Brassica napus L. at Varying Plant Densities

    Directory of Open Access Journals (Sweden)

    Ming Li

    2017-01-01

    Full Text Available In this study, the yield and yield components were studied using a conventional variety Zhongshuang 11 (ZS 11 and a hybrid variety Zhongyouza 12 (ZYZ 12 at varying plant densities. The increase in plant density led to an initial increase in seed yield and pod numbers per unit area, followed by a decrease. The optimal plant density was 58.5 × 104 plants ha−1 in both ZS 11 and ZYZ 12. The further researches on physiological traits showed a rapid decrease in the green leaf area index (GLAI and chlorophyll content and a remarkable increase in malondialdehyde content in high plant density (HPD population than did the low plant density (LPD population, which indicated the rapid leaf senescence. However, HPD had higher values in terms of pod area index (PAI, pod photosynthesis, and radiation use efficiency (RUE after peak anthesis. A significantly higher level of dry matter accumulation and nitrogen utilization efficiency were observed, which resulted in higher yield. HPD resulted in a rapid decrease in root morphological parameters (root length, root tips, root surface area, and root volume. These results suggested that increasing the plant density within a certain range was a promising option for high seed yield in winter rapeseed in China.

  12. Photosynthesis, light use efficiency, and yield of reduced-chlorophyll soybean mutants in field conditions

    Science.gov (United States)

    Reducing chlorophyll (chl) content may improve the conversion efficiency of absorbed radiation into biomass (ec) and therefore yield in dense monoculture crops by improving light penetration and distribution within the canopy. Modeling suggests that reducing chl content may also reduce leaf temperat...

  13. Approaches to achieve high grain yield and high resource use efficiency in rice

    Directory of Open Access Journals (Sweden)

    Jianchang YANG

    2015-06-01

    Full Text Available This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

  14. Yielding of leaf celery Apium graveolens L. var. secalinum Alef. depending on the number of harvests and irrigation

    Directory of Open Access Journals (Sweden)

    Ewa Rożek

    2013-04-01

    Full Text Available Leaf celery (Apium graveolensvar. secalinum is a vegetable with medicinal and spicy properties. Its numerous intensely fragrant leaves can be cut several times during the plant growing period. The aim of this study was to evaluate the effect of irrigation and number of harvests on leaf celery yield of the cultivars ‘Afina’ and‘Gewone Snij’. Plant irrigation significantly increased leaf yield and plant height of leaf celery. Higher total yield was obtained from non-irrigated plants when leaves were harvested three times, whereas for irrigated plants yield was higher in the case of two leaf harvests. Irrespective of the experimental factors, higher yield was obtained from the cultivar ‘Gewone Snij’.

  15. A hairy-leaf gene, BLANKET LEAF, of wild Oryza nivara increases photosynthetic water use efficiency in rice.

    Science.gov (United States)

    Hamaoka, Norimitsu; Yasui, Hideshi; Yamagata, Yoshiyuki; Inoue, Yoko; Furuya, Naruto; Araki, Takuya; Ueno, Osamu; Yoshimura, Atsushi

    2017-12-01

    High water use efficiency is essential to water-saving cropping. Morphological traits that affect photosynthetic water use efficiency are not well known. We examined whether leaf hairiness improves photosynthetic water use efficiency in rice. A chromosome segment introgression line (IL-hairy) of wild Oryza nivara (Acc. IRGC105715) with the genetic background of Oryza sativa cultivar 'IR24' had high leaf pubescence (hair). The leaf hairs developed along small vascular bundles. Linkage analysis in BC 5 F 2 and F 3 populations showed that the trait was governed by a single gene, designated BLANKET LEAF (BKL), on chromosome 6. IL-hairy plants had a warmer leaf surface in sunlight, probably due to increased boundary layer resistance. They had a lower transpiration rate under moderate and high light intensities, resulting in higher photosynthetic water use efficiency. Introgression of BKL on chromosome 6 from O. nivara improved photosynthetic water use efficiency in the genetic background of IR24.

  16. Response of maize varieties to nitrogen application for leaf area profile, crop growth, yield and yield components

    International Nuclear Information System (INIS)

    Akmal, M.; Hameed-urRehman; Farhatullah; Asim, M.; Akbar, H.

    2010-01-01

    An experiment was conducted at NWFP Agricultural University, Peshawar, to study maize varieties and Nitrogen (N) rates for growth, yield and yield components. Three varieties (Azam, Jalal and Sarhad white) and three N rates (90, 120, 150, kg N ha/sup -1/) were compared. Experiment was conducted in a Randomized Complete Block design; split plot arrangement with 4 replications. Uniform and recommended cultural practices were applied during the crop growth. The results revealed that maize variety 'Jalal' performed relatively better crop growth rate (CGR) and leaf area profile (LAP) at nodal position one to six as compared to the other two varieties (Sarhad white and Azam). This resulted higher radiation use efficiency by the crop canopy at vegetative stage of development and hence contributed higher assimilates towards biomass production. Heavier grains in number and weight were due to higher LAP and taller plants of Jalal which yielded higher in the climate. Nitrogen applications have shown that maize seed yield increase in quadratic fashion with increased N to a plateau level. Considering soil fertility status and cropping system, the 150 kg ha/sup -1/ N application to maize variety Jalal in Peshawar is required for maximum biological and seed production. (author)

  17. DIFFERENCES IN LEAF GAS EXCHANGE AND LEAF CHARACTERISTICS BETWEEN TWO ALMOND CULTIVARS

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    George D. Nanos

    2013-12-01

    Full Text Available Leaf chlorophyll content, specific leaf weight (SLW, photosynthetic and transpiration rates, stomatal functioning, water use efficiency and quantum yield were assessed during the kernel filling period for two consecutive years in order to understand tissue-centered physiological profile differences between two commercial almond cultivars, ‘Ferragnès’ and ‘Texas’. Similar SLWs were observed on the studied cultivars; however, chlorophyll content, net photosynthetic and transpiration rates and stomatal functioning demonstrated statistically significant differences. In both cultivars, an overall decline in the examined parameters towards fruit maturation (i.e. end of the summer was recorded. ‘Ferragnès’ leaves were found to be more efficient in leaf photosynthesis related performance during kernel filling, when irrigated sufficiently, in comparison to ‘Texas’ leaves. Low average values of leaf conductance during summer in ‘Texas’ leaves revealed its potential for adaptation in cool climates and increased carbon assimilation therein for high kernel yield.

  18. Difference in leaf water use efficiency/photosynthetic nitrogen use efficiency of Bt-cotton and its conventional peer.

    Science.gov (United States)

    Guo, Ruqing; Sun, Shucun; Liu, Biao

    2016-09-15

    This study is to test the effects of Bt gene introduction on the foliar water/nitrogen use efficiency in cotton. We measured leaf stomatal conductance, photosynthetic rate, and transpiration rate under light saturation condition at different stages of a conventional cultivar (zhongmian no. 16) and its counterpart Bt cultivar (zhongmian no. 30) that were cultured on three levels of fertilization, based on which leaf instantaneous water use efficiency was derived. Leaf nitrogen concentration was measured to calculate leaf photosynthetic nitrogen use efficiency, and leaf δ(13)C was used to characterize long term water use efficiency. Bt cultivar was found to have lower stomatal conductance, net photosynthetic rates and transpiration rates, but higher instantaneous and long time water use efficiency. In addition, foliar nitrogen concentration was found to be higher but net photosynthetic rate was lower in the mature leaves of Bt cultivar, which led to lower photosynthetic nitrogen use efficiency. This might result from the significant decrease of photosynthetic rate due to the decrease of stomatal conductance. In conclusion, our findings show that the introduction of Bt gene should significantly increase foliar water use efficiency but decrease leaf nitrogen use efficiency in cotton under no selective pressure.

  19. Leaf gas exchange and yield of three upland rice cultivars

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Félix Alvarez

    2015-03-01

    Full Text Available Studies of physiological parameters associated with crop performance and growth in different groups of upland rice (Oryza sativa L. may support plant breeding programs. We evaluated the role of gas exchange rates and dry matter accumulation (DMA as traits responsible for yields in a traditional (cv. ‘Caiapó’, intermediate (cv. ‘Primavera’ and modern (cv. ‘Maravilha’ upland rice cultivars. Leaf gas exchange rates, DMA, leaf area index (LAI, harvest indexes (HI and yield components were measured on these genotypes in the field, under sprinkler irrigation. Panicles per m2 and DMA at flowering (FL and heading, as well as CO2 assimilation rates (A were similar across these cultivars. The highest yield was found in ‘Primavera’, which may be explained by (i a two-fold higher HI compared to the other cultivars, (ii greater rates of DMA during spikelet formation and grain-filling, as well as (iii a slow natural decrease of A in this cultivar, at the end of the season (between FL and maturation.

  20. Green light drives leaf photosynthesis more efficiently than red light in strong white light: revisiting the enigmatic question of why leaves are green.

    Science.gov (United States)

    Terashima, Ichiro; Fujita, Takashi; Inoue, Takeshi; Chow, Wah Soon; Oguchi, Riichi

    2009-04-01

    The literature and our present examinations indicate that the intra-leaf light absorption profile is in most cases steeper than the photosynthetic capacity profile. In strong white light, therefore, the quantum yield of photosynthesis would be lower in the upper chloroplasts, located near the illuminated surface, than that in the lower chloroplasts. Because green light can penetrate further into the leaf than red or blue light, in strong white light, any additional green light absorbed by the lower chloroplasts would increase leaf photosynthesis to a greater extent than would additional red or blue light. Based on the assessment of effects of the additional monochromatic light on leaf photosynthesis, we developed the differential quantum yield method that quantifies efficiency of any monochromatic light in white light. Application of this method to sunflower leaves clearly showed that, in moderate to strong white light, green light drove photosynthesis more effectively than red light. The green leaf should have a considerable volume of chloroplasts to accommodate the inefficient carboxylation enzyme, Rubisco, and deliver appropriate light to all the chloroplasts. By using chlorophylls that absorb green light weakly, modifying mesophyll structure and adjusting the Rubisco/chlorophyll ratio, the leaf appears to satisfy two somewhat conflicting requirements: to increase the absorptance of photosynthetically active radiation, and to drive photosynthesis efficiently in all the chloroplasts. We also discuss some serious problems that are caused by neglecting these intra-leaf profiles when estimating whole leaf electron transport rates and assessing photoinhibition by fluorescence techniques.

  1. Leaf gas exchange, carbon isotope discrimination, and grain yield in contrasting rice genotypes subjected to water deficits during the reproductive stage.

    Science.gov (United States)

    Centritto, Mauro; Lauteri, Marco; Monteverdi, Maria Cristina; Serraj, Rachid

    2009-01-01

    Genotypic variations in leaf gas exchange and yield were analysed in five upland-adapted and three lowland rice cultivars subjected to a differential soil moisture gradient, varying from well-watered to severely water-stressed conditions. A reduction in the amount of water applied resulted in a significant decrease in leaf gas exchange and, subsequently, in above-ground dry mass and grain yield, that varied among genotypes and distance from the line source. The comparison between the variable J and the Delta values in recently synthesized sugars methods, yielded congruent estimations of mesophyll conductance (g(m)), confirming the reliability of these two techniques. Our data demonstrate that g(m) is a major determinant of photosynthesis (A), because rice genotypes with inherently higher g(m) were capable of keeping higher A in stressed conditions. Furthermore, A, g(s), and g(m) of water-stressed genotypes rapidly recovered to the well-watered values upon the relief of water stress, indicating that drought did not cause any lasting metabolic limitation to photosynthesis. The comparisons between the A/C(i) and corresponding A/C(c) curves, measured in the genotypes that showed intrinsically higher and lower instantaneous A, confirmed this finding. Moreover, the effect of drought stress on grain yield was correlated with the effects on both A and total diffusional limitations to photosynthesis. Overall, these data indicate that genotypes which showed higher photosynthesis and conductances were also generally more productive across the entire soil moisture gradient. The analysis of Delta revealed a substantial variation of water use efficiency among the genotypes, both on the long-term (leaf pellet analysis) and short-term scale (leaf soluble sugars analysis).

  2. The effect of strobilurins on leaf gas exchange, water use efficiency and ABA content in grapevine under field conditions.

    Science.gov (United States)

    Diaz-Espejo, Antonio; Cuevas, María Victoria; Ribas-Carbo, Miquel; Flexas, Jaume; Martorell, Sebastian; Fernández, José Enrique

    2012-03-01

    Strobilurins are one of the most important classes of agricultural fungicides. In addition to their anti-fungal effect, strobilurins have been reported to produce simultaneous effects in plant physiology. This study investigated whether the use of strobilurin fungicide improved water use efficiency in leaves of grapevines grown under field conditions in a Mediterranean climate in southern Spain. Fungicide was applied three times in the vineyard and measurements of leaf gas exchange, plant water status, abscisic acid concentration in sap ([ABA]), and carbon isotope composition in leaves were performed before and after applications. No clear effect on stomatal conductance, leaf water potential and intrinsic water use efficiency was found after three fungicide applications. ABA concentration was observed to increase after fungicide application on the first day, vanishing three days later. Despite this transient effect, evolution of [ABA] matched well with the evolution of leaf carbon isotope ratio, which can be used as a surrogate for plant water use efficiency. Morning stomatal conductance was negatively correlated to [ABA]. Yield was enhanced in strobilurin treated plants, whereas fruit quality remained unaltered. Published by Elsevier GmbH.

  3. The effects of different nitrogen doses on yield, quality and leaf ...

    African Journals Online (AJOL)

    ONOS

    2010-08-09

    Aug 9, 2010 ... The effects of different nitrogen doses on yield, quality and leaf nitrogen content of some early grape cultivars. (V. vinifera L.) grown in greenhouse. Hatice Bilir Ekbic1, Gultekin Ozdemir2, Ali Sabir3* and Semih Tangolar1. 1Department of Horticulture, Faculty of Agriculture, University of Cukurova, Adana, ...

  4. Influence of rootstocks on growth, yield, fruit quality and leaf mineral element contents of pear cv. 'Santa Maria' in semi-arid conditions

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    Ali Ikinci

    2014-01-01

    Full Text Available BACKGROUND: Rootstocks play an essential role to determining orchard performance of fruit trees. Pyrus communisand Cydonia oblonga are widely used rootstocks for European pear cultivars. The lack of rootstocks adapted to different soil conditions and different grafted cultivars is widely acknowledged in pear culture. Cydonia rootstocks (clonal and Pyrus rootstocks (seedling or clonal have their advantages and disadvantages. In each case, site-specific environmental characteristics, specific cultivar response and production objectives must be considered before choosing the best rootstock. In this study, the influence of three Quince (BA 29, Quince A = MA, Quince C = MC and a local European pear seedling rootstocks on the scion yield, some fruit quality characteristics and leaf macro (N, P, K, Ca and Mg and micro element (Fe, Zn, Cu, Mn and B content of 'Santa Maria' pear (Pyrus communis L. were investigated. RESULTS: Trees on seedling rootstock had the highest annual yield, highest cumulative yield (kg tree−1, largest trunk cross-sectional area (TCSA, lowest yield efficiency and lowest cumulative yield (ton ha−1 in the 10th year after planting. The rootstocks had no significant effect on average fruit weight and fruit volume. Significantly higher fruit firmness was obtained on BA 29 and Quince A. The effect of rootstocks on the mineral element accumulation (N, K, Ca, Mg, Fe, Zn, Cu, Mn and B was significant. Leaf analysis showed that rootstocks used had different mineral uptake efficiencies throughout the early season. CONCLUSION: The results showed that the rootstocks strongly affected fruit yield, fruit quality and leaf mineral element uptake of 'Santa Maria' pear cultivar. Pear seedling and BA 29 rootstock found to be more prominent in terms of several characteristics for 'Santa Maria' pear cultivar that is grown in highly calcareous soil in semi-arid climate conditions. We determined the highest N, P (although insignificant, K, Ca, Mg, Fe

  5. Field evaluations of leaf spot resistance and yield in peanut genotypes in the United States and Bolivia

    Science.gov (United States)

    Field experiments were conducted in 2002-2006 to characterize yield potential and disease resistance to Cercospora arachidicola (early leaf spot) and Cercosporidium personatum (late leaf spot) in the Bolivian peanut (Arachis hypogaea) cultivar, Bayo Grande, and breeding lines developed from crosses ...

  6. Growth and yield response to plant density of water leaf ( Talinum ...

    African Journals Online (AJOL)

    The effects of different planting spaces (15cm x 15cm, 20cm x 20cm, 25cm x 25cm and 30cm x 30cm) on the growth and yield of Talinum triangulare (Water leaf) were investigated in two cropping seasons from 2012 to 2013 (rainy and dry seasons) at University of Port Harcourt Teaching and Research farm, Port Harcourt, ...

  7. PHOTOSYNTHETIC EFFICIENCY IN JUVENILE STAGE AND WINTER BARLEY BREEDING FOR IMPROVED GRAIN YIELD AND STABILITY

    Directory of Open Access Journals (Sweden)

    Josip Kovačević

    2011-06-01

    Full Text Available Photosynthetic efficiency parameters (Fv/Fm, ET0/ABS and PIABS were investigated at the end of tillering stage of winter barley grown in stress environment (21.3% vol. water content of soil and control (water content 30.4% vol. in relation to grain yield per vegetative pot. The trial was conducted in vegetative pots according to the RBD method of two-factorial experiment with 10 winter barley cultivars (7 tworowed and 3 six-rowed and 2 treatments in 3 repetitions. The stressed variant was exposed to water reduction three times (end of tillering stage, flag leaf to beginning of heading stage, grain filling stage. From sowing to maturity, the air temperature varied from -3.9°C to 32.9°C and water content from 16.4 % to 39.0 % of soil volume in vegetative pot. Significant differences were found for grain yield among the cultivars. The short-term drought stress caused significant reductions in grain yield per pot. The photosynthetic efficiency parameters were significant between cultivars, but significant effects for treatments and interaction were only detected for the Fv/Fm parameter. Photosynthetic efficiency parameters did not have significant correlation coefficients with grain yield and its stability in both treatments. Stability indexes of the parameters PIABS and Fv/Fm had positive but not significant correlations with grain yield in stressed variant (0.465 and 0.452 and stability index of grain yield (0.337 and 0.481.

  8. Role of aquaporins in determining transpiration and photosynthesis in water-stressed plants: crop water-use efficiency, growth and yield.

    Science.gov (United States)

    Moshelion, Menachem; Halperin, Ofer; Wallach, Rony; Oren, Ram; Way, Danielle A

    2015-09-01

    The global shortage of fresh water is one of our most severe agricultural problems, leading to dry and saline lands that reduce plant growth and crop yield. Here we review recent work highlighting the molecular mechanisms allowing some plant species and genotypes to maintain productivity under water stress conditions, and suggest molecular modifications to equip plants for greater production in water-limited environments. Aquaporins (AQPs) are thought to be the main transporters of water, small and uncharged solutes, and CO2 through plant cell membranes, thus linking leaf CO2 uptake from the intercellular airspaces to the chloroplast with water loss pathways. AQPs appear to play a role in regulating dynamic changes of root, stem and leaf hydraulic conductivity, especially in response to environmental changes, opening the door to using AQP expression to regulate plant water-use efficiency. We highlight the role of vascular AQPs in regulating leaf hydraulic conductivity and raise questions regarding their role (as well as tonoplast AQPs) in determining the plant isohydric threshold, growth rate, fruit yield production and harvest index. The tissue- or cell-specific expression of AQPs is discussed as a tool to increase yield relative to control plants under both normal and water-stressed conditions. © 2014 John Wiley & Sons Ltd.

  9. Leaf area development, dry weight accumulation and solar energy conversion efficiencies of Phaseolus vulgaris L. under different soil moisture levels near Nairobi, Kenya

    NARCIS (Netherlands)

    Muniafu, M.M.; Macharia, J.N.M.; Stigter, C.J.; Coulson, G.L.

    1999-01-01

    Leaf area development, dry weight accumulation and solar energy conversion efficiencies of Phaseolus vulgaris L. cv GLP-2 under two soil moisture levels in two contrasting seasons near Nairobi, Kenya were investigated. The experiment confirms that dry weights and yields of Phaseolus vulgaris are

  10. Investigating the Effect of Cultivate Lines Direction, Bio-Fertilizer Nitroxin and Superabsorbent Materials on Yield and Yield Components of Broad Leaf Vetch (Vicia narbonensis

    Directory of Open Access Journals (Sweden)

    E Latifinia

    2017-12-01

    Full Text Available Introduction The excessive use of fertilizers has caused severe damages to the bio-cycle in the fields and has destroyed the sustainable agricultural machinery. These destructive effects have led to the recommended use of bio-fertilizers. Biodiversity is one of the key sources of supplying nutrients in sustainable agriculture. The use of biological fertilizers in a sustainable agricultural system leads to sustained yield in plant production. Biological fertilizer of nitroxin has increased biological yield and grain yield in fodder corn. Water shortage as a limiting factor has limited vegetation growth and development in these areas. Considering that Iran is a dry country, the use of super adsorbent is one of the ways to reduce water consumption. Investigators in the study of superabsorbent showed that superabsorbent had a significant and positive effect on the yield of forage plants. Crop directions can affect the amount of the product by increasing the leaf area and absorbing light. Proper orientation of crop lines increases the photosynthetic efficiency and increases the yield and yield components of the plant. Research has shown that yields are much higher in plants planted on the north-south lines compared with plants planted on east-west lines. Materials and Methods In order to investigate the effect of nitroxin and superabsorbent fertilizer on yield and yield components of broad leaf vetch in a research field of agricultural faculty, Lorestan University, as a split plot factorial based on a complete block design randomization was performed in three replicates. In this research, for main lines, the main factors were considered in the North-South and East-West directions in the main plots. Sub-factors In this experiment, nitroxin biosynthesis and superabsorbent materials were applied at two levels of consumption and non-consumption in sub plots. Nitroxin fertilizer was used as a seed lot at a rate of 1 liter per hectare and the stockosorb

  11. Effects of ozone on growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat (Triticum aestivum L.)

    International Nuclear Information System (INIS)

    Akhtar, Nahid; Yamaguchi, Masahiro; Inada, Hidetoshi; Hoshino, Daiki; Kondo, Taisuke; Izuta, Takeshi

    2010-01-01

    To clarify the effects of O 3 on crop plants cultivated in Bangladesh, two Bangladeshi wheat cultivars (Sufi and Bijoy) were grown in plastic boxes filled with Andisol and exposed daily to charcoal-filtered air or O 3 at 60 and 100 nl l -1 (10:00-17:00) from 13 March to 4 June 2008. The whole-plant dry mass and grain yield per plant of the two cultivars at the final harvest were significantly reduced by the exposure to O 3 . Although there was no significant effect of O 3 on stomatal diffusive conductance to H 2 O of flag leaf, net photosynthetic rate of the leaf was significantly reduced by the exposure to O 3. The sensitivity of growth, yield, yield components and leaf gas exchange rates to O 3 was not significantly different between the two cultivars. The results obtained in the present study suggest that ambient levels of O 3 may detrimentally affect wheat production in Bangladesh. - The exposure to ambient levels of ozone decreases growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat.

  12. Modern maize hybrids in Northeast China exhibit increased yield potential and resource use efficiency despite adverse climate change.

    Science.gov (United States)

    Chen, Xiaochao; Chen, Fanjun; Chen, Yanling; Gao, Qiang; Yang, Xiaoli; Yuan, Lixing; Zhang, Fusuo; Mi, Guohua

    2013-03-01

    The impact of global changes on food security is of serious concern. Breeding novel crop cultivars adaptable to climate change is one potential solution, but this approach requires an understanding of complex adaptive traits for climate-change conditions. In this study, plant growth, nitrogen (N) uptake, and yield in relation to climatic resource use efficiency of nine representative maize cultivars released between 1973 and 2000 in China were investigated in a 2-year field experiment under three N applications. The Hybrid-Maize model was used to simulate maize yield potential in the period from 1973 to 2011. During the past four decades, the total thermal time (growing degree days) increased whereas the total precipitation and sunshine hours decreased. This climate change led to a reduction of maize potential yield by an average of 12.9% across different hybrids. However, the potential yield of individual hybrids increased by 118.5 kg ha(-1)  yr(-1) with increasing year of release. From 1973 to 2000, the use efficiency of sunshine hours, thermal time, and precipitation resources increased by 37%, 40%, and 41%, respectively. The late developed hybrids showed less reduction in yield potential in current climate conditions than old cultivars, indicating some adaptation to new conditions. Since the mid-1990s, however, the yield impact of climate change exhibited little change, and even a slight worsening for new cultivars. Modern breeding increased ear fertility and grain-filling rate, and delayed leaf senescence without modification in net photosynthetic rate. The trade-off associated with delayed leaf senescence was decreased grain N concentration rather than increased plant N uptake, therefore N agronomic efficiency increased simultaneously. It is concluded that modern maize hybrids tolerate the climatic changes mainly by constitutively optimizing plant productivity. Maize breeding programs in the future should pay more attention to cope with the limiting

  13. Impact of leaf motion constraints on IMAT plan quality, deliver accuracy, and efficiency

    International Nuclear Information System (INIS)

    Chen Fan; Rao Min; Ye Jinsong; Shepard, David M.; Cao Daliang

    2011-01-01

    Purpose: Intensity modulated arc therapy (IMAT) is a radiation therapy delivery technique that combines the efficiency of arc based delivery with the dose painting capabilities of intensity modulated radiation therapy (IMRT). A key challenge in developing robust inverse planning solutions for IMAT is the need to account for the connectivity of the beam shapes as the gantry rotates from one beam angle to the next. To overcome this challenge, inverse planning solutions typically impose a leaf motion constraint that defines the maximum distance a multileaf collimator (MLC) leaf can travel between adjacent control points. The leaf motion constraint ensures the deliverability of the optimized plan, but it also impacts the plan quality, the delivery accuracy, and the delivery efficiency. In this work, the authors have studied leaf motion constraints in detail and have developed recommendations for optimizing the balance between plan quality and delivery efficiency. Methods: Two steps were used to generate optimized IMAT treatment plans. The first was the direct machine parameter optimization (DMPO) inverse planning module in the Pinnacle 3 planning system. Then, a home-grown arc sequencer was applied to convert the optimized intensity maps into deliverable IMAT arcs. IMAT leaf motion constraints were imposed using limits of between 1 and 30 mm/deg. Dose distributions were calculated using the convolution/superposition algorithm in the Pinnacle 3 planning system. The IMAT plan dose calculation accuracy was examined using a finer sampling calculation and the quality assurance verification. All plans were delivered on an Elekta Synergy with an 80-leaf MLC and were verified using an IBA MatriXX 2D ion chamber array inserted in a MultiCube solid water phantom. Results: The use of a more restrictive leaf motion constraint (less than 1-2 mm/deg) results in inferior plan quality. A less restrictive leaf motion constraint (greater than 5 mm/deg) results in improved plan quality

  14. Effects of species-specific leaf characteristics and reduced water availability on fine particle capture efficiency of trees

    International Nuclear Information System (INIS)

    Räsänen, Janne V.; Holopainen, Toini; Joutsensaari, Jorma; Ndam, Collins; Pasanen, Pertti; Rinnan, Åsmund; Kivimäenpää, Minna

    2013-01-01

    Trees can improve air quality by capturing particles in their foliage. We determined the particle capture efficiencies of coniferous Pinus sylvestris and three broadleaved species: Betula pendula, Betula pubescens and Tilia vulgaris in a wind tunnel using NaCl particles. The importance of leaf surface structure, physiology and moderate soil drought on the particle capture efficiencies of the trees were determined. The results confirm earlier findings of more efficient particle capture by conifers compared to broadleaved plants. The particle capture efficiency of P. sylvestris (0.21%) was significantly higher than those of B. pubescens, T. vulgaris and B. pendula (0.083%, 0.047%, 0.043%, respectively). The small leaf size of P. sylvestris was the major characteristic that increased particle capture. Among the broadleaved species, low leaf wettability, low stomatal density and leaf hairiness increased particle capture. Moderate soil drought tended to increase particle capture efficiency of P. sylvestris. -- Highlights: • Coniferous Scots pine was the most efficient particle collector. • Decreasing single leaf size increases particle deposition of the total leaf area. • Hairiness of the leaf increases particle deposition. -- Trees can improve air quality by removing PM 2.5 pollutants carried on the wind at a velocity of 3 m s −1 , the efficiency of which depends on species leaf characteristics and physical factors

  15. Estimating grain yield losses caused by septoria leaf blotch on durum wheat in Tunisia

    Directory of Open Access Journals (Sweden)

    Samia Berraies

    2014-12-01

    Full Text Available Septoria leaf blotch (SLB, caused by Zymoseptoria tritici (Desm. Quaedvlieg & Crous, 2011 (teleomorph: Mycosphaerella graminicola (Fuckel J. Schrot., is an important wheat disease in the Mediterranean region. In Tunisia, SLB has become a major disease of durum wheat (Triticum turgidum L. subsp. durum [Desf.] Husn. particularly during favorable growing seasons where significant yield losses and increase of fungicides use were recorded over the last three decades. The objectives of this study were to evaluate the effect of SLB severity on grain yield of new elite durum wheat breeding lines and to measure the relative effect of fungicide control on grain yield. Experiments were conducted during 2007-2008 and 2008-2009 cropping seasons. A set of 800 breeding lines were screened for reaction to SLB under natural infection at Beja research station. To estimate the disease effect, correlation between disease severity at early grain filling stage and grain yield was performed. Results showed that susceptible varieties yield was significantly reduced by SLB. Average yield reduction was as high as 384 and 325 kg ha-1 for every increment in disease severity on a 0-9 scale in both seasons, respectively. A negative correlation coefficient varied between -0.61 and -0.66 in both seasons. Treated and untreated trials conducted during 2008-2009 and 2009-2010 showed that yield of treated plots increased by 50% on the commonly cultivated susceptible varieties. The results of this investigation suggested that septoria incidence is related to large grain yield losses particularly on susceptible high yielding cultivars. However, appropriate fungicide application at booting growth stage could be beneficial for farmers. The development and use of more effective fungicide could be sought to alleviate the disease effects and therefore could be considered as a part of the integrated pest management and responsible use strategy on septoria leaf blotch in Tunisia.

  16. [Flag leaf photosynthetic characteristics, change in chlorophyll fluorescence parameters, and their relationships with yield of winter wheat sowed in spring].

    Science.gov (United States)

    Xu, Lan; Gao, Zhi-qang; An, Wei; Li, Yan-liang; Jiao, Xiong-fei; Wang, Chuang-yun

    2016-01-01

    With five good winter wheat cultivars selected from the middle and lower reaches of Yangtze River and Southwest China as test materials, a field experiment in Xinding basin area of Shanxi Province was conducted to study the photosynthetic characteristics, chlorophyll content, and chlorophyll fluorescence parameters of flag leaf at different sowing dates, as well as the correlations between these indices and yield for two years (2013-2014). The results showed that the difference in most fluorescence parameters except chlorophyll content among cultivars was significant. The correlations between these fluorescence parameters and yield were significant. The variation coefficient of chlorophyll (Chl) content was low (0.12-0.17), and that of performance index based on absorption (PIabs) was high (0.32-0.39), with the partial correlation coefficients of them with grain yield from 2013 to 2014 ranged in 0.70-0.81. Under the early sowing condition, the grain yield positively correlated with PIabs at flowering and filling stages and chlorophyll content at grain filling stage, but negatively correlated with the relative variable fluorescence at I point (Vi) at grain filling stage. About 81.1%-82.8% of grain yield were determined by the variations of PIabs, Chl, and Vi. Wheat cultivars had various performances in the treatments with different sowing dates and a consistent trend was observed in the two experimental years. Among these 5 cultivars, Yangmai 13 was suitable for early sowing, with the flag leaf photosynthetic rate (Pn), Chl, most fluorescence parame-ters, and grain yield showed obviously high levels. In conclusion, under early sowing condition chlorophyll content at grain filling stages, PIabs at flowering and filling stages, and Pn were important indices for selecting wheat cultivars with high photosynthetic efficiency.

  17. Leaf transpiration efficiency of some drought-resistant maize lines

    Science.gov (United States)

    Field measurements of leaf gas exchange in maize often indicate stomatal conductances higher than required to provide substomatal carbon dioxide concentrations saturating to photosynthesis. Thus maize leaves often operate at lower transpiration efficiency (TE) than potentially achievable for specie...

  18. From leaf to whole-plant water use efficiency (WUE in complex canopies: Limitations of leaf WUE as a selection target

    Directory of Open Access Journals (Sweden)

    Hipólito Medrano

    2015-06-01

    Full Text Available Plant water use efficiency (WUE is becoming a key issue in semiarid areas, where crop production relies on the use of large volumes of water. Improving WUE is necessary for securing environmental sustainability of food production in these areas. Given that climate change predictions include increases in temperature and drought in semiarid regions, improving crop WUE is mandatory for global food production. WUE is commonly measured at the leaf level, because portable equipment for measuring leaf gas exchange rates facilitates the simultaneous measurement of photosynthesis and transpiration. However, when those measurements are compared with daily integrals or whole-plant estimates of WUE, the two sometimes do not agree. Scaling up from single-leaf to whole-plant WUE was tested in grapevines in different experiments by comparison of daily integrals of instantaneous water use efficiency [ratio between CO2 assimilation (AN and transpiration (E; AN/E] with midday AN/E measurements, showing a low correlation, being worse with increasing water stress. We sought to evaluate the importance of spatial and temporal variation in carbon and water balances at the leaf and plant levels. The leaf position (governing average light interception in the canopy showed a marked effect on instantaneous and daily integrals of leaf WUE. Night transpiration and respiration rates were also evaluated, as well as respiration contributions to total carbon balance. Two main components were identified as filling the gap between leaf and whole plant WUE: the large effect of leaf position on daily carbon gain and water loss and the large flux of carbon losses by dark respiration. These results show that WUE evaluation among genotypes or treatments needs to be revised.

  19. Herbivory mitigation through increased water-use efficiency in a leaf-mining moth-apple tree relationship.

    Science.gov (United States)

    Pincebourde, Sylvain; Frak, Ela; Sinoquet, Hervé; Regnard, Jean Luc; Casas, Jérôme

    2006-12-01

    Herbivory alters plant gas exchange but the effects depend on the type of leaf damage. In contrast to ectophagous insects, leaf miners, by living inside the leaf tissues, do not affect the integrity of the leaf surface. Thus, the effect of leaf miners on CO2 uptake and water-use efficiency by leaves remains unclear. We explored the impacts of the leaf-mining moth Phyllonorycter blancardella (Lepidoptera: Gracillariidae) on light responses of the apple leaf gas exchanges to determine the balance between the negative effects of reduced photosynthesis and potential positive impacts of increased water-use efficiency (WUE). Gas exchange in intact and mined leaf tissues was measured using an infrared gas analyser. The maximal assimilation rate was slightly reduced but the light response of net photosynthesis was not affected in mined leaf tissues. The transpiration rate was far more affected than the assimilation rate in the mine integument as a result of stomatal closure from moderate to high irradiance level. The WUE was about 200% higher in the mined leaf tissues than in intact leaf portions. Our results illustrate a novel mechanism by which plants might minimize losses from herbivore attacks; via trade-offs between the negative impacts on photosynthesis and the positive effects of increased WUE.

  20. Leaf-level carbon isotope discrimination and its relationship with yield components as a tool for cotton phenotyping in unfavorable conditions

    Directory of Open Access Journals (Sweden)

    Giovani Greigh Brito

    2014-07-01

    Full Text Available The initial goal of this study was to measure the efficiency of carbon isotope discrimination (Δ in distinguishing between cotton plant genotypes subjected to two water regimes. In addition, ∆ measurements, leaf water potential and gas exchange ratios were monitored. Using Brazilian breeding lines, this study also tested the usability of ∆ as a proxy for selecting high-performing yield components in cotton plants grown in unfavorable conditions, particularly water deficiency. For these experiments, ∆ and yield components were measured and their correlations analyzed. Differences among cotton genotypes for Δ (p < 0.0001 were verified, and it was found that this variable was significantly correlated with gas exchange. There was a significant positive correlation between Δ and seed cotton yield only in the site experiencing severe water deficiency (Santa Helena de Goiás. However, Δ had a significant negative correlation with fiber percentage. Our results indicate that Δ is a suitable tool for cotton phenotyping, and it may be applied in cotton breeding programs that aim to produce high-performing yield components in unfavorable conditions.

  1. The effect of water deficit stress and nitrogen fertilizer levels on morphology traits, yield and leaf area index in maize

    International Nuclear Information System (INIS)

    Moosavi, S.G.

    2012-01-01

    In order to study the effect of water deficit stress at different growth stages and N fertilizer levels on morphological traits, yield and yield components of maize cv. Single Cross 704, an experiment was conducted as a split-plot based on a Randomized Complete Block Design with three replications. The main plot included irrigation at four levels (irrigation stop at 10-leaf, tasselling and grain-filling stages and optimum irrigation) and the sub-plot was N fertilizer at three levels (75, 150 and 225 kg N/ha). The results of analysis of variance showed that water-deficit stress and N fertilizer level significantly affected leaf area index at silking stage, ear length, grain number per ear, 1000-grain weight and grain yield. Stem diameter, ear diameter and harvest index were only affected by irrigation treatments and the interaction between irrigation and N level did not significantly affect the studied traits. Means comparison indicated that ear diameter under optimum irrigation was higher than that under the treatments of irrigation stop at 8-leaf, tasselling and grain-filling stages by 29.9, 19.1 and 33.5%, respectively; and ear length was higher than them by 38.1, 28.9 and 25.2%, respectively. Moreover, the highest grain number per ear, 1000-grain weight and grain yield were obtained under optimum irrigation treatment, and irrigation stop at 10-leaf, tasselling and grain-filling stages decreased grain yield by 52.8, 66.4 and 44.9%, respectively; and it decreased grain number/ear by 45.9, 59.3 and 30.1%, respectively. In addition, optimum irrigation treatment with mean 1000-grain weight of 289.2 g was significantly superior over other irrigation stop treatments by 27.6-42.8% and produced the highest leaf area index at silking stage (4.1). Means comparison of traits at different N levels indicated that N level of 225 kg/ha produced the highest ear length (17.82 cm), grain number per ear (401.9), 1000-grain weight (258.8 g), leaf area index at silking stage (4

  2. Leaf chlorophyll and nitrogen dynamics and their relationship to lowland rice yield for site-specific paddy management

    Directory of Open Access Journals (Sweden)

    Asa Gholizadeh

    2017-12-01

    Full Text Available The optimum rate and application timing of Nitrogen (N fertilizer are crucial in achieving a high yield in rice cultivation; however, conventional laboratory testing of plant nutrients is time-consuming and expensive. To develop a site-specific spatial variable rate application method to overcome the limitations of traditional techniques, especially in fields under a double-cropping system, this study focused on the relationship between Soil Plant Analysis Development (SPAD chlorophyll meter readings and N content in leaves during different growth stages to introduce the most suitable stage for assessment of crop N and prediction of rice yield. The SPAD readings and leaf N content were measured on the uppermost fully expanded leaf at panicle formation and booting stages. Grain yield was also measured at the end of the season. The analysis of variance, variogram, and kriging were calculated to determine the variability of attributes and their relationship, and finally, variability maps were created. Significant linear relationships were observed between attributes, with the same trends in different sampling dates; however, accuracy of semivariance estimation reduces with the growth stage. Results of the study also implied that there was a better relationship between rice leaf N content (R2 = 0.93, as well as yield (R2 = 0.81, with SPAD readings at the panicle formation stage. Therefore, the SPAD-based evaluation of N status and prediction of rice yield is more reliable on this stage rather than at the booting stage. This study proved that the application of SPAD chlorophyll meter paves the way for real-time paddy N management and grain yield estimation. It can be reliably exploited in precision agriculture of paddy fields under double-cropping cultivation to understand and control spatial variations. Keywords: Spatial variability, Non-invasive measurement, Precision farming, Decision support

  3. Maize YABBY genes drooping leaf1 and drooping leaf2 affect agronomic traits by regulating leaf architecture

    Science.gov (United States)

    Leaf architectural traits, such as length, width and angle, directly influence canopy structure and light penetration, photosynthate production and overall yield. We discovered and characterized a maize (Zea mays) mutant with aberrant leaf architecture we named drooping leaf1 (drl1), as leaf blades ...

  4. Variation for yield, water-use efficiency, and canopy morphology among nine alfalfa germplasms

    International Nuclear Information System (INIS)

    Ray, I.M.; Townsend, M.S.; Henning, J.A.

    1998-01-01

    Alfalfa (Medicago sativa L.) production under irrigated and rainfed conditions may benefit from improvements in water-use efficiency (WUE), the amount of forage and root biomass produced per unit of water transpired. If benefits from improved WUE are to be realized, correlations between important agronomic traits and key physiological traits associated with WUE must be determined. This study characterized variation for dry matter yield, forage maturity, leaf-to-stem ratio (LSR), carbon isotope discrimination (delta), canopy temperature, ash content, and specific leaf mass (SLM) in alfalfa. Associations between traits were also determined. Nine alfalfa germplasms representing eight of the nine historical genetic diversity groups, and a very fall-dormant (VFD) population, were established in seeded, irrigated plots for 2 yr near Las Cruces, NM. Significant variation (P less than or equal to 0.10) was detected for all traits and was greatest for delta and maturity, intermediate for yield, canopy temperature, ash content, and LSR, and least for SLM. The African, Peruvian, and Indian germplasms exhibited a higher delta than either the Turkistan, VFD, M. varia Martyn., or Ladak germplasms. Carbon isotope discrimination was positively correlated with forage yield (r = 0.64; P less than or equal to 0.10; n = 9) and forage maturity (r = 0.66; P less than or equal to 0.05; n = 9). No association was detected between delta and either canopy temperature, ash content, SLM, or LSR. The results indicate that differences in stomatal conductance or photosynthetic capacity exist among the nine populations, and that germplasms with low delta tended to have slower growth and development rates under irrigated conditions. Neither canopy temperature, ash content, nor SLM provided suitable alternate measurements of delta among the nine alfalfa germplasms

  5. Mid-Season Leaf Glutamine Predicts End-Season Maize Grain Yield and Nitrogen Content in Response to Nitrogen Fertilization under Field Conditions

    Directory of Open Access Journals (Sweden)

    Travis Goron

    2017-06-01

    Full Text Available After uptake in cereal crops, nitrogen (N is rapidly assimilated into glutamine (Gln and other amino acids for transport to sinks. Therefore Gln has potential as an improved indicator of soil N availability compared to plant N demand. Gln has primarily been assayed to understand basic plant physiology, rather than to measure plant/soil-N under field conditions. It was hypothesized that leaf Gln at early-to-mid season could report the N application rate and predict end-season grain yield in field-grown maize. A three-year maize field experiment was conducted with N application rates ranging from 30 to 218 kg ha−1. Relative leaf Gln was assayed from leaf disk tissue using a whole-cell biosensor for Gln (GlnLux at the V3-V14 growth stages. SPAD (Soil Plant Analysis Development and NDVI (Normalized Difference Vegetation Index measurements were also performed. When sampled at V6 or later, GlnLux glutamine output consistently correlated with the N application rate, end-season yield, and grain N content. Yield correlation outperformed GreenSeekerTM NDVI, and was equivalent to SPAD chlorophyll, indicating the potential for yield prediction. Additionally, depleting soil N via overplanting increased GlnLux resolution to the earlier V5 stage. The results of the study are discussed in the context of luxury N consumption, leaf N remobilization, senescence, and grain fill. The potential and challenges of leaf Gln and GlnLux for the study of crop N physiology, and future N management are also discussed.

  6. Leaf area and light use efficiency patterns of Norway spruce under different thinning regimes and age classes

    Science.gov (United States)

    Gspaltl, Martin; Bauerle, William; Binkley, Dan; Sterba, Hubert

    2013-01-01

    Silviculture focuses on establishing forest stand conditions that improve the stand increment. Knowledge about the efficiency of an individual tree is essential to be able to establish stand structures that increase tree resource use efficiency and stand level production. Efficiency is often expressed as stem growth per unit leaf area (leaf area efficiency), or per unit of light absorbed (light use efficiency). We tested the hypotheses that: (1) volume increment relates more closely with crown light absorption than leaf area, since one unit of leaf area can receive different amounts of light due to competition with neighboring trees and self-shading, (2) dominant trees use light more efficiently than suppressed trees and (3) thinning increases the efficiency of light use by residual trees, partially accounting for commonly observed increases in post-thinning growth. We investigated eight even-aged Norway spruce (Picea abies (L.) Karst.) stands at Bärnkopf, Austria, spanning three age classes (mature, immature and pole-stage) and two thinning regimes (thinned and unthinned). Individual leaf area was calculated with allometric equations and absorbed photosynthetically active radiation was estimated for each tree using the three-dimensional crown model Maestra. Absorbed photosynthetically active radiation was only a slightly better predictor of volume increment than leaf area. Light use efficiency increased with increasing tree size in all stands, supporting the second hypothesis. At a given tree size, trees from the unthinned plots were more efficient, however, due to generally larger tree sizes in the thinned stands, an average tree from the thinned treatment was superior (not congruent in all plots, thus only partly supporting the third hypothesis). PMID:25540477

  7. TaER Expression Is Associated with Transpiration Efficiency Traits and Yield in Bread Wheat.

    Science.gov (United States)

    Zheng, Jiacheng; Yang, Zhiyuan; Madgwick, Pippa J; Carmo-Silva, Elizabete; Parry, Martin A J; Hu, Yin-Gang

    2015-01-01

    ERECTA encodes a receptor-like kinase and is proposed as a candidate for determining transpiration efficiency of plants. Two genes homologous to ERECTA in Arabidopsis were identified on chromosomes 6 (TaER2) and 7 (TaER1) of bread wheat (Triticum aestivum L.), with copies of each gene on the A, B and D genomes of wheat. Similar expression patterns were observed for TaER1 and TaER2 with relatively higher expression of TaER1 in flag leaves of wheat at heading (Z55) and grain-filling (Z73) stages. Significant variations were found in the expression levels of both TaER1 and TaER2 in the flag leaves at both growth stages among 48 diverse bread wheat varieties. Based on the expression of TaER1 and TaER2, the 48 wheat varieties could be classified into three groups having high (5 varieties), medium (27 varieties) and low (16 varieties) levels of TaER expression. Significant differences were also observed between the three groups varying for TaER expression for several transpiration efficiency (TE)- related traits, including stomatal density (SD), transpiration rate, photosynthetic rate (A), instant water use efficiency (WUEi) and carbon isotope discrimination (CID), and yield traits of biomass production plant-1 (BYPP) and grain yield plant-1 (GYPP). Correlation analysis revealed that the expression of TaER1 and TaER2 at the two growth stages was significantly and negatively associated with SD (Ptranspiration rate (Ptranspiration efficiency -related traits and yield in bread wheat, implying a function for TaER in regulating leaf development of bread wheat and contributing to expression of these traits. Moreover, the results indicate that TaER could be exploitable for manipulating important agronomical traits in wheat improvement.

  8. Up-scaling of water use efficiency from leaf to canopy as based on leaf gas exchange relationships and the modeled in-canopy light distribution

    DEFF Research Database (Denmark)

    Linderson, Maj-Lena; Mikkelsen, Teis Nørgaard; Ibrom, Andreas

    2012-01-01

    The aim of this study was to evaluate the extent to which water use efficiency (WUE) at leaf scale can be used to assess WUE at canopy scale, leaf WUE being assumed to be a constant function of vapor pressure deficit and to thus not be dependent upon other environmental factors or varying leaf...... properties. Leaf WUE and its variability and dependencies were assessed using leafgas-exchange measurements obtained during two growing seasons, 1999 and 2000, at the Soroe beech forest study site on Zealand in Denmark. It was found that the VPD-normalized leaf WUE, WUEnormleaf, although dependent...

  9. Genotypic variation of nitrogen use efficiency in Indian mustard

    International Nuclear Information System (INIS)

    Ahmad, Altaf; Khan, Ishrat; Abrol, Yash P.; Iqbal, Muhammad

    2008-01-01

    This experiment was conducted to investigate the variation of nitrogen efficiency (NE), nitrogen uptake efficiency (UE), physiological nitrogen use efficiency (PUE) among Indian mustard genotypes, grown under N-insufficient and N-sufficient conditions. Nitrogen efficiency varied from 52.7 to 92.8. Seed yield varied from 1.14 t ha -1 to 3.21 t ha -1 under N-insufficient condition, while 2.14 t ha -1 -3.33 t ha -1 under N-sufficient condition. Physiological basis of this difference was explained in terms of nitrogen uptake efficiency and physiological nitrogen use efficiency, and their relationship with the growth and yield characteristics. While nitrogen uptake efficiency was positively correlated with plant biomass (0.793**), leaf area index (0.664*), and leaf nitrogen content (0.783**), physiological nitrogen use efficiency is positively correlated with photosynthetic rate (0.689**) and yield (0.814**). This study suggests that genotype having high nitrogen uptake efficiency and high physiological nitrogen use efficiency might help in reducing the nitrogen load on soil without any penalty on the yield. - Nitrogen efficient crop plants may help in reducing environmental contamination of nitrate without any penalty on seed yield

  10. Radiation use efficiency and yield of winter wheat under deficit irrigation in North China

    International Nuclear Information System (INIS)

    Han, H.; Li, Z.; Ning, T.; Bai, M.; Zhang, X.; Shan, Y.

    2008-01-01

    An experiment was conducted in North China to investigate the effects of deficit irrigation and winter wheat varieties on the photosynthetic active radiation (PAR) capture ration, PAR utilization and grain yield. Field experiments involved Jimai 20 (J; high yield variety) and Lainong 0153 (L; dryland variety) with non-irrigation and irrigated at the jointing stage. The results showed that whether irrigated at jointing stage or not, there was no significant difference between J and L with respect to the amount of PAR intercepted by the winter wheat canopies. However, significant differences were observed between the varieties with respect to the amount of PAR intercepted by plants that were 60-80 cm above the ground surface. This result was mainly caused by the changes in the vertical distributions of leaf area index. As a result, the effects of the varieties and deficit irrigation on the radiation use efficiency (RUE) and grain yield of winter wheat were due to the vertical distribution of PAR in the winter wheat canopies. During the late growing season of winter wheat, irrespective of the irrigation regime, the RUE and grain yield of J were significantly higher than those of L. These results suggest that a combination of deficit irrigation and a suitable winter wheat variety should be applied in North China

  11. Phenotypic selection on leaf water use efficiency and related ecophysiological traits for natural populations of desert sunflowers.

    Science.gov (United States)

    Donovan, Lisa A; Dudley, Susan A; Rosenthal, David M; Ludwig, Fulco

    2007-05-01

    Plant water-use efficiency (WUE) is expected to affect plant fitness and thus be under natural selection in arid habitats. Although many natural population studies have assessed plant WUE, only a few related WUE to fitness. The further determination of whether selection on WUE is direct or indirect through functionally related traits has yielded no consistent results. For natural populations of two desert annual sunflowers, Helianthus anomalus and H. deserticola, we used phenotypic selection analysis with vegetative biomass as the proxy for fitness to test (1) whether there was direct and indirect selection on WUE (carbon isotope ratio) and related traits (leaf N, area, succulence) and (2) whether direct selection was consistent with hypothesized drought/dehydration escape and avoidance strategies. There was direct selection for lower WUE in mesic and dry H. anomalus populations, consistent with dehydration escape, even though it is the longer lived of the two species. For mesic H. anomalus, direct selection favored lower WUE and higher N, suggesting that plants may be "wasting water" to increase N delivery via the transpiration stream. For the shorter lived H. deserticola in the direr habitat, there was indirect selection for lower WUE, inconsistent with drought escape. There was also direct selection for higher leaf N, succulence and leaf size. There was no direct selection for higher WUE consistent with dehydration avoidance in either species. Thus, in these natural populations of two desert dune species higher fitness was associated with some combination direct and indirect selection for lower WUE, higher leaf N and larger leaf size. Our understanding of the adaptive value of plant ecophysiological traits will benefit from further consideration of related traits such as leaf nitrogen and more tests in natural populations.

  12. Antibacterial, Antibiofilm Effect of Burdock (Arctium lappa L.) Leaf Fraction and Its Efficiency in Meat Preservation.

    Science.gov (United States)

    Lou, Zaixiang; Li, Cheng; Kou, Xingran; Yu, Fuhao; Wang, Hongxin; Smith, Gary M; Zhu, Song

    2016-08-01

    First, the antibacterial, antibiofilm effect and chemical composition of burdock (Arctium lappa L.) leaf fractions were studied. Then, the efficiency of burdock leaf fractions in pork preservation was evaluated. The results showed that burdock leaf fraction significantly inhibited the growth and biofilm development of Escherichia coli and Salmonella Typhimurium. MICs of burdock leaf fractions on E. coli and Salmonella Typhimurium were both 2 mg/ml. At a concentration of 2.0 mg/ml, the inhibition rates of the fraction on growth and development of E. coli and Salmonella Typhimurium biofilms were 78.7 and 69.9%, respectively. During storage, the log CFU per gram of meat samples treated with burdock leaf fractions decreased 2.15, compared with the samples without treatment. The shelf life of pork treated with burdock leaf fractions was extended 6 days compared with the pork without treatment, and the sensory property was obviously improved. Compared with the control group, burdock leaf fraction treatment significantly decreased the total volatile basic nitrogen value and pH of the meat samples. Chemical composition analysis showed that the burdock leaf fraction consisted of chlorogenic acid, caffeic acid, p-coumaric acid, rutin, cynarin, crocin, luteolin, arctiin, and quercetin. As a vegetable with an abundant source, burdock leaf is safe, affordable, and efficient in meat preservation, indicating that burdock leaf fraction is a promising natural preservative for pork.

  13. Prediction of the competitive effects of weeds on crop yields based on the relative leaf area of weeds

    DEFF Research Database (Denmark)

    Lotz, L. A. P.; Christensen, Svend; Cloutier, D.

    1996-01-01

    . alba whereas the density model did not. A parameter that allows the maximum yield loss to be smaller than 100% was mostly not needed to describe the effects of weed competition. The parameter that denotes the competitiveness of the weed species with respect to the crop decreased the later the relative......For implementation of simple yield loss models into threshold-based weed management systems, a thorough validation is needed over a great diversity of sites. Yield losses by competition wsth Sinapis alba L. (white mustard) as a model weed, were studied in 12 experiments in sugar beet (Beta vulgaris...... L.) and in 11 experiments in spring wheat (Triticum aestivum L.). Most data sets were heller described by a model based on the relative leaf area of the weed than by a hyperbolic model based on weed density. This leaf area model accounted for (part of) the effect of different emerging times of the S...

  14. Effect of different rates of potassium fertilizer on nitrogen use efficiency and cotton yield using an 15N isotopic dilution technique

    International Nuclear Information System (INIS)

    Khalifa, Kh.; Al-Chamma'a, M.; Al-Ain, F.

    2005-03-01

    A field study was carried out during the 2003 growing season on a loamy to sandy clay loamy soil, located at the Lower Euphrate's Valley, 15 km southeast of Deir - Ezzor city to evaluate the effect of K fertilizer on nitrogen , potassium use efficiency and cotton yield. Three nitrogen ( N1 =120, N2 =180, and N3 = 240 kg N / ha ) and four potassium application rates ( K0 = 0 , K1 = 50, K2 = 100, K3 = 150 kg K2O / ha ) were employed. The cotton variety was Deir 22 sown on April 2003 at a spacing of 70 cm between rows and 20 cm between pits with 5 seeds per pit. The plants were thinned to 2 plants per pit 4 weeks after planting. Representative samples of aboveground portions of cotton plants were harvested from labeled subplots at 108 and 161 days after planting . Dry matter weight , N uptake, N fertilizer yield, N use efficiency, K use efficiency, seed cotton yield, earliness, leaf area, number of bolls / plant, and number of branches / plant were evaluated. The results showed that seed cotton yield increased with increasing K levels applied under each rate of N ( except N120 ). The highest seed cotton yield was obtained with the combined treatment N3K1 ( 6442 kg/ha ). This treatment gave also the optimum potassium use efficiency ( 42 % ). Nitrogen use efficiency (at 180 days of harvest ) increased with the increasing K application rate. Nitrogen use efficiency (NUE) was decreased with increasing N rates . Increasing K application rate ( KUE ) decreased potassium use efficiency. A maximum N use efficiency ( 98% ) was obtained for combined treatment N2 K3. Also the results indicated that dry matter weight and N uptake increased with increasing K rates applied. Nitrogen derived from fertilizer (Ndff ) was higher in combined treatments than the control treatments (K0 ). (Authors)

  15. Effects of some growth regulating applications on leaf yield, raw ...

    African Journals Online (AJOL)

    This study investigated the effects of repetitive applications of herbagreen (HG), humic acid (HA), combined foliar fertilizer (CFF) and HG+CFF performed in the Müsküle grape variety grafted on 5 BB rootstock on fresh or pickled leaf size and leaf raw cellulose content. HA application increased leaf area and leaf water ...

  16. Genetic variation in transpiration efficiency and relationships between whole plant and leaf gas exchange measurements in Saccharum spp. and related germplasm.

    Science.gov (United States)

    Jackson, Phillip; Basnayake, Jaya; Inman-Bamber, Geoff; Lakshmanan, Prakash; Natarajan, Sijesh; Stokes, Chris

    2016-02-01

    Fifty-one genotypes of sugarcane (Saccharum spp.) or closely related germplasm were evaluated in a pot experiment to examine genetic variation in transpiration efficiency. Significant variation in whole plant transpiration efficiency was observed, with the difference between lowest and highest genotypes being about 40% of the mean. Leaf gas exchange measurements were made across a wide range of conditions. There was significant genetic variation in intrinsic transpiration efficiency at a leaf level as measured by leaf internal CO2 (Ci) levels. Significant genetic variation in Ci was also observed within subsets of data representing narrow ranges of stomatal conductance. Ci had a low broad sense heritability (Hb = 0.11) on the basis of single measurements made at particular dates, because of high error variation and genotype × date interaction, but broad sense heritability for mean Ci across all dates was high (Hb = 0.81) because of the large number of measurements taken at different dates. Ci levels among genotypes at mid-range levels of conductance had a strong genetic correlation (-0.92 ± 0.30) with whole plant transpiration efficiency but genetic correlations between Ci and whole plant transpiration efficiency were weaker or not significant at higher and lower levels of conductance. Reduced Ci levels at any given level of conductance may result in improved yields in water-limited environments without trade-offs in rates of water use and growth. Targeted selection and improvement of lowered Ci per unit conductance via breeding may provide longer-term benefits for water-limited environments but the challenge will be to identify a low-cost screening methodology. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. [Characteristics of phosphorus uptake and use efficiency of rice with high yield and high phosphorus use efficiency].

    Science.gov (United States)

    Li, Li; Zhang, Xi-Zhou; Li, Tinx-Xuan; Yu, Hai-Ying; Ji, Lin; Chen, Guang-Deng

    2014-07-01

    A total of twenty seven middle maturing rice varieties as parent materials were divided into four types based on P use efficiency for grain yield in 2011 by field experiment with normal phosphorus (P) application. The rice variety with high yield and high P efficiency was identified by pot experiment with normal and low P applications, and the contribution rates of various P efficiencies to yield were investigated in 2012. There were significant genotype differences in yield and P efficiency of the test materials. GRLu17/AiTTP//Lu17_2 (QR20) was identified as a variety with high yield and high P efficiency, and its yields at the low and normal rates of P application were 1.96 and 1.92 times of that of Yuxiang B, respectively. The contribution rate of P accumulation to yield was greater than that of P grain production efficiency and P harvest index across field and pot experiments. The contribution rates of P accumulation and P grain production efficiency to yield were not significantly different under the normal P condition, whereas obvious differences were observed under the low P condition (66.5% and 26.6%). The minimal contribution to yield was P harvest index (11.8%). Under the normal P condition, the contribution rates of P accumulation to yield and P harvest index were the highest at the jointing-heading stage, which were 93.4% and 85.7%, respectively. In addition, the contribution rate of P accumulation to grain production efficiency was 41.8%. Under the low P condition, the maximal contribution rates of P accumulation to yield and grain production efficiency were observed at the tillering-jointing stage, which were 56.9% and 20.1% respectively. Furthermore, the contribution rate of P accumulation to P harvest index was 16.0%. The yield, P accumulation, and P harvest index of QR20 significantly increased under the normal P condition by 20.6%, 18.1% and 18.2% respectively compared with that in the low P condition. The rank of the contribution rates of P

  18. Relations among Valencia orange yields with soil and leaf nutrients in Northwestern Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Jonez Fidalski

    2000-01-01

    Full Text Available The Valencia orange orchards established on soils of low fertility in the Northwest region of Paraná State, Brazil, have showed symptoms of Mg deficiency and reduced fruit yields. The objective of this study was to verify the relationship between yield with soil and leaf nutrients during 1996/97 growing season. Two sites of low and high productivity were selected in seven orchards. Leaf and soil samples (fertilized rows and interrows were collected in 1996. The results showed that the citrus yields were negatively related with soil Mg/K and Ca+Mg/K ratios in the fertilized rows, and fruit weight positively correlated with leaf Zn in the low productivity orchards. The fruit weight was positively related with leaf Ca and soil Ca in the fertilized rows of the high productivity orchards. The results suggested an adequate lime and K fertilization managements in the fertilized rows, as well as an adequate Zn supply.Os pomares de laranja Valência (Citrus sinensis (L. Osbeck estabelecidos em solos de baixa fertilidade da região noroeste do Paraná, tem apresentado sintomas de desequilíbrio nutricional, principalmente deficiência de Mg e redução da produção e do tamanho dos frutos. O objetivo deste trabalho foi verificar as relações da produção e peso dos frutos com os nutrientes das folhas e do solo de sete pomares de laranja Valência na safra de 1996/97, em talhões de produtividade inferior e superior. Em 1996, foram coletadas amostras de folha e de solo nas faixas de adubação e nas entrelinhas. Os resultados mostraram que a produção de frutos correlacionou-se negativamente com as relações dos cátions Mg/K e Ca+Mg/K do solo das faixas de adubação dos pomares de baixa produtividade e, o peso dos frutos, correlacionou-se positivamente com os teores foliares de Zn. Nos pomares de produtividade superior, o peso dos frutos correlacionou-se positivamente com os teores de Ca das folhas e do solo nas faixas de adubação. Estes

  19. Performance of a two-leaf light use efficiency model for mapping gross primary productivity against remotely sensed sun-induced chlorophyll fluorescence data.

    Science.gov (United States)

    Zan, Mei; Zhou, Yanlian; Ju, Weimin; Zhang, Yongguang; Zhang, Leiming; Liu, Yibo

    2018-02-01

    Estimating terrestrial gross primary production is an important task when studying the carbon cycle. In this study, the ability of a two-leaf light use efficiency model to simulate regional gross primary production in China was validated using satellite Global Ozone Monitoring Instrument - 2 sun-induced chlorophyll fluorescence data. The two-leaf light use efficiency model was used to estimate daily gross primary production in China's terrestrial ecosystems with 500-m resolution for the period from 2007 to 2014. Gross primary production simulated with the two-leaf light use efficiency model was resampled to a spatial resolution of 0.5° and then compared with sun-induced chlorophyll fluorescence. During the study period, sun-induced chlorophyll fluorescence and gross primary production simulated by the two-leaf light use efficiency model exhibited similar spatial and temporal patterns in China. The correlation coefficient between sun-induced chlorophyll fluorescence and monthly gross primary production simulated by the two-leaf light use efficiency model was significant (pproduction simulated by the two-leaf light use efficiency model were similar in spring and autumn in most vegetated regions, but dissimilar in winter and summer. The spatial variability of sun-induced chlorophyll fluorescence and gross primary production simulated by the two-leaf light use efficiency model was similar in spring, summer, and autumn. The proportion of spatial variations of sun-induced chlorophyll fluorescence and annual gross primary production simulated by the two-leaf light use efficiency model explained by ranged from 0.76 (2011) to 0.80 (2013) during the study period. Overall, the two-leaf light use efficiency model was capable of capturing spatial and temporal variations in gross primary production in China. However, the model needs further improvement to better simulate gross primary production in summer. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Effect of Plant Growth Regulators on Leaf Number, Leaf Area and Leaf Dry Matter in Grape

    Directory of Open Access Journals (Sweden)

    Zahoor Ahmad BHAT

    2011-03-01

    Full Text Available Influence of phenylureas (CPPU and brassinosteriod (BR along with GA (gibberellic acid were studied on seedless grape vegetative characteristics like leaf number, leaf area and leaf dry matter. Growth regulators were sprayed on the vines either once (7 days after fruit set or 15 days after fruit set or twice (7+15 days after fruit set. CPPU 2 ppm+BR 0.4 ppm+GA 25 ppm produced maximum number of leaves (18.78 while as untreated vines produced least leaf number (16.22 per shoot. Maximum leaf area (129.70 cm2 and dry matter content (26.51% was obtained with higher CPPU (3 ppm and BR (0.4 ppm combination along with GA 25 ppm. Plant growth regulators whether naturally derived or synthetic are used to improve the productivity and quality of grapes. The relatively high value of grapes justifies more expensive inputs. A relatively small improvement in yield or fruit quality can justify the field application of a very costly product. Application of new generation growth regulators like brassinosteroids and phenylureas like CPPU have been reported to increase the leaf number as well as leaf area and dry matter thereby indirectly influencing the fruit yield and quality in grapes.

  1. Nitrogen efficiency in oats on grain yield with stability

    Directory of Open Access Journals (Sweden)

    José A. G. da Silva

    Full Text Available ABSTRACT Nitrogen (N is the nutrient most absorbed by the oat crop. Unfavorable climate conditions decrease its efficiency, generating instability and reduction in yield. The objective of this study was to improve N use efficiency in oat grain yield by the economic value of the product and of the input and by models that scale the stability, considering systems of succession of high and reduced residual-N release in favorable and unfavorable years for cultivation. The study was conducted in the years 2013, 2014 and 2015 in two systems of succession (soybean/oat, maize/oat in randomized blocks with eight replicates, using the N-fertilizer doses of 0, 30, 60 and 120 kg ha-1. The N-fertilizer dose for maximum economic efficiency in oats should be considered based on the meteorological trends of the cultivation year. N use optimization by models that determine the stability is an innovative proposal to increase fertilization efficiency on the yield. The N-fertilizer dose of 60 kg ha-1 promotes greater efficiency with predictability and yield, regardless of the agricultural year and the system of succession.

  2. Drought priming at vegetative growth stage enhances nitrogen-use efficiency under post-anthesis drought and heat stress in wheat

    DEFF Research Database (Denmark)

    Liu, S.; Li, Xiangnan; Larsen, Dorthe Horn

    2017-01-01

    reached ca. −0.9 MPa) at the 5th-leaf stage for 11 days, and leaf water relations and gas exchange rates, grain yield and yield components, and agronomic nitrogen-use efficiency (ANUE) of the primed and non-primed plants under post-anthesis drought and heat stress were investigated. Compared with the non......To study the effects of early drought priming at 5th-leaf stage on grain yield and nitrogen-use efficiency in wheat (Triticum aestivum L.) under post-anthesis drought and heat stress, wheat plants were first exposed to moderate drought stress (drought priming; that is, the leaf water potential......-primed plants, the drought-primed plants possessed higher leaf water potential and chlorophyll content, and consequently a higher photosynthetic rate during post-anthesis drought and heat stress. Drought priming also resulted in higher grain yield and ANUE in wheat under post-anthesis drought and heat stress...

  3. Rational Water and Nitrogen Management Improves Root Growth, Increases Yield and Maintains Water Use Efficiency of Cotton under Mulch Drip Irrigation

    Directory of Open Access Journals (Sweden)

    Hongzhi Zhang

    2017-05-01

    Full Text Available There is a need to optimize water-nitrogen (N applications to increase seed cotton yield and water use efficiency (WUE under a mulch drip irrigation system. This study evaluated the effects of four water regimes [moderate drip irrigation from the third-leaf to the boll-opening stage (W1, deficit drip irrigation from the third-leaf to the flowering stage and sufficient drip irrigation thereafter (W2, pre-sowing and moderate drip irrigation from the third-leaf to the boll-opening stage (W3, pre-sowing and deficit drip irrigation from the third-leaf to the flowering stage and sufficient drip irrigation thereafter (W4] and N fertilizer at a rate of 520 kg ha-1 in two dressing ratios [7:3 (N1, 2:8 (N2] on cotton root morpho-physiological attributes, yield, WUE and the relationship between root distribution and dry matter production. Previous investigations have shown a strong correlation between root activity and water consumption in the 40–120 cm soil layer. The W3 and especially W4 treatments significantly increased root length density (RLD, root volume density (RVD, root mass density (RMD, and root activity in the 40–120 cm soil layer. Cotton RLD, RVD, RMD was decreased by 13.1, 13.3, and 20.8%, respectively, in N2 compared with N1 at 70 days after planting (DAP in the 0–40 cm soil layer. However, root activity in the 40–120 cm soil layer at 140 DAP was 31.6% higher in N2 than that in N1. Total RMD, RLD and root activity in the 40–120 cm soil were significantly and positively correlated with shoot dry weight. RLD and root activity in the 40–120 cm soil layer was highest in the W4N2 treatments. Therefore increased water consumption in the deep soil layers resulted in increased shoot dry weight, seed cotton yield and WUE. Our data can be used to develop a water-N management strategy for optimal cotton yield and high WUE.

  4. How Does Alkali Aid Protein Extraction in Green Tea Leaf Residue: A Basis for Integrated Biorefinery of Leaves

    Science.gov (United States)

    Zhang, Chen; Sanders, Johan P. M.; Xiao, Ting T.; Bruins, Marieke E.

    2015-01-01

    Leaf protein can be obtained cost-efficiently by alkaline extraction, but overuse of chemicals and low quality of (denatured) protein limits its application. The research objective was to investigate how alkali aids protein extraction of green tea leaf residue, and use these results for further improvements in alkaline protein biorefinery. Protein extraction yield was studied for correlation to morphology of leaf tissue structure, protein solubility and hydrolysis degree, and yields of non-protein components obtained at various conditions. Alkaline protein extraction was not facilitated by increased solubility or hydrolysis of protein, but positively correlated to leaf tissue disruption. HG pectin, RGII pectin, and organic acids were extracted before protein extraction, which was followed by the extraction of cellulose and hemi-cellulose. RGI pectin and lignin were both linear to protein yield. The yields of these two components were 80% and 25% respectively when 95% protein was extracted, which indicated that RGI pectin is more likely to be the key limitation to leaf protein extraction. An integrated biorefinery was designed based on these results. PMID:26200774

  5. How Does Alkali Aid Protein Extraction in Green Tea Leaf Residue: A Basis for Integrated Biorefinery of Leaves.

    Directory of Open Access Journals (Sweden)

    Chen Zhang

    Full Text Available Leaf protein can be obtained cost-efficiently by alkaline extraction, but overuse of chemicals and low quality of (denatured protein limits its application. The research objective was to investigate how alkali aids protein extraction of green tea leaf residue, and use these results for further improvements in alkaline protein biorefinery. Protein extraction yield was studied for correlation to morphology of leaf tissue structure, protein solubility and hydrolysis degree, and yields of non-protein components obtained at various conditions. Alkaline protein extraction was not facilitated by increased solubility or hydrolysis of protein, but positively correlated to leaf tissue disruption. HG pectin, RGII pectin, and organic acids were extracted before protein extraction, which was followed by the extraction of cellulose and hemi-cellulose. RGI pectin and lignin were both linear to protein yield. The yields of these two components were 80% and 25% respectively when 95% protein was extracted, which indicated that RGI pectin is more likely to be the key limitation to leaf protein extraction. An integrated biorefinery was designed based on these results.

  6. Leaf transpiration efficiency of sweet corn varieties from three eras of breeding

    Science.gov (United States)

    When measured under midday field conditions, modern varieties of corn often have sub-stomatal concentrations of carbon dioxide in excess of those required to saturate photosynthesis. This results in lower leaf transpiration efficiency, the ratio of photosynthesis to transpiration, than potentially ...

  7. Effects of spring prescribed fire on short-term, leaf-level photosynthesis and water use efficiency in longleaf pine

    Science.gov (United States)

    John K. Jackson; Dylan N. Dillaway; Michael C. Tyree; Mary Anne Sword Sayer

    2015-01-01

    Fire is a natural and important environmental disturbance influencing the structure, function, and composition of longleaf pine (Pinus palustris Mill.) ecosystems. However, recovery of young pines to leaf scorch may involve changes in leaf physiology, which could influence leaf water-use efficiency (WUE). This work is part of a larger seasonal...

  8. Effects of fully open-air [CO2] elevation on leaf photosynthesis and ultrastructure of Isatis indigotica fort.

    Science.gov (United States)

    Hao, Xingyu; Li, Ping; Feng, Yongxiang; Han, Xue; Gao, Ji; Lin, Erda; Han, Yuanhuai

    2013-01-01

    Traditional Chinese medicine relies heavily on herbs, yet there is no information on how these herb plants would respond to climate change. In order to gain insight into such response, we studied the effect of elevated [CO2] on Isatis indigotica Fort, one of the most popular Chinese herb plants. The changes in leaf photosynthesis, chlorophyll fluorescence, leaf ultrastructure and biomass yield in response to elevated [CO2] (550±19 µmol mol(-1)) were determined at the Free-Air Carbon dioxide Enrichment (FACE) experimental facility in North China. Photosynthetic ability of I. indigotica was improved under elevated [CO2]. Elevated [CO2] increased net photosynthetic rate (P N), water use efficiency (WUE) and maximum rate of electron transport (J max) of upper most fully-expended leaves, but not stomatal conductance (gs), transpiration ratio (Tr) and maximum velocity of carboxylation (V c,max). Elevated [CO2] significantly increased leaf intrinsic efficiency of PSII (Fv'/Fm') and quantum yield of PSII(ΦPS II ), but decreased leaf non-photochemical quenching (NPQ), and did not affect leaf proportion of open PSII reaction centers (qP) and maximum quantum efficiency of PSII (Fv/Fm). The structural chloroplast membrane, grana layer and stroma thylakoid membranes were intact under elevated [CO2], though more starch grains were accumulated within the chloroplasts than that of under ambient [CO2]. While the yield of I. indigotica was higher due to the improved photosynthesis under elevated [CO2], the content of adenosine, one of the functional ingredients in indigowoad root was not affected.

  9. Quantifying the non-fungicidal effects of foliar applications of fluxapyroxad (Xemium) on stomatal conductance, water use efficiency and yield in winter wheat.

    Science.gov (United States)

    Smith, J; Grimmer, M; Waterhouse, S; Paveley, N

    2013-01-01

    The active ingredient fluxapyroxad belongs to the chemical group of carboxamides and is a new generation succinate dehydrogenase inhibitor (SDHI) in complex II of the mitochondrial respiratory chain. It has strong efficacy against the key foliar diseases of winter wheat in the UK: Septoria leaf blotch, yellow stripe rust and brown rust. Fluxapyroxad is marketed under the brand name of Xemium, was launched in 2012 and is available in the UK as a solo product (Imtrex) for co-application with triazoles, in co-formulation with epoxiconazole (Adexar), or in a three way formulation with epoxiconazole and pyraclostrobin (Ceriax). The objective of the study was to quantify the direct effects of Xemium on stomatal conductance and yield, mediated through stimulation of host physiology. Three field experiments and two controlled environment (CE) experiments were conducted across three cropping seasons (2010-2012) in Herefordshire and Cambridge, in the UK. Xemium was evaluated against boscalid, pyraclostrobin (F500), epoxiconazole and an untreated control. Across site-seasons, disease severity was significantly reduced when Xemium was applied as a foliar spray. Healthy canopy size and duration was increased by Xemium and canopy greening effects were seen shortly after application. Stomatal conductance was found to be consistently lower in Xemium treated plants but reduced stomatal opening was not found to be detrimental to yield in these experiments. Large, beneficial effects of Xemium on water use efficiency were found at the canopy level and this finding was supported by measurements of instantaneous water use efficiency at the leaf level. Effects on season long water use efficiency were largely driven by improvements in yield for a given amount of water uptake. Foliar applications of Xemium reduced the water required to produce 1.0 t grain per hectare by 82,330 L(82 t) when compared with an untreated crop. Yield was significantly higher in Xemium treatments and this was

  10. Quantification of growth, yield and radiation use efficiency of promising cotton cultivars at varying nitrogen levels

    International Nuclear Information System (INIS)

    Wajid, A.; Ahmad, A.; Khaliq, T.; Alam, S.; Hussaun, A.; Hussain, K.; Naseem, W.; Usman, M.; Ahmad, S.

    2010-01-01

    Cotton cultivars response to different doses of nitrogen for radiation interception, canopy development, growth and seed yield were studied in 2006. The experiment was laid out in randomized complete block design with split arrangement under the climatic conditions of Bahawalpur. Data on seed yield, total dry matter (TDM), leaf area index (LAI), fraction of intercepted radiation (Fi), accumulated radiation interception during the growth season (Sa) and radiation use efficiency (RUE) were taken into account. TDM pattern showed sigmoid growth curve for both cultivars and nitrogen levels and showed strong relationship (R2 = 0.98) with the accumulated intercepted radiation (Sa) for the season. Mean maximum value of fraction of incident PAR (Fi) remained 90% at 120 days after sowing (DAS) harvest due to maximum crop canopy development. Cultivar NIAB-111 produced 0.81 g m/sup -2/ of TDM for each MJ of accumulated PAR and nitrogen at the rate of 185 kg ha/sup -1/ statistically proved to be better in converting radiation into dry matter production. (author)

  11. Performance of Linear and Nonlinear Two-Leaf Light Use Efficiency Models at Different Temporal Scales

    DEFF Research Database (Denmark)

    Wu, Xiaocui; Ju, Weimin; Zhou, Yanlian

    2015-01-01

    The reliable simulation of gross primary productivity (GPP) at various spatial and temporal scales is of significance to quantifying the net exchange of carbon between terrestrial ecosystems and the atmosphere. This study aimed to verify the ability of a nonlinear two-leaf model (TL-LUEn), a linear...... two-leaf model (TL-LUE), and a big-leaf light use efficiency model (MOD17) to simulate GPP at half-hourly, daily and 8-day scales using GPP derived from 58 eddy-covariance flux sites in Asia, Europe and North America as benchmarks. Model evaluation showed that the overall performance of TL...

  12. Assimilating Remote Sensing Observations of Leaf Area Index and Soil Moisture for Wheat Yield Estimates: An Observing System Simulation Experiment

    Science.gov (United States)

    Nearing, Grey S.; Crow, Wade T.; Thorp, Kelly R.; Moran, Mary S.; Reichle, Rolf H.; Gupta, Hoshin V.

    2012-01-01

    Observing system simulation experiments were used to investigate ensemble Bayesian state updating data assimilation of observations of leaf area index (LAI) and soil moisture (theta) for the purpose of improving single-season wheat yield estimates with the Decision Support System for Agrotechnology Transfer (DSSAT) CropSim-Ceres model. Assimilation was conducted in an energy-limited environment and a water-limited environment. Modeling uncertainty was prescribed to weather inputs, soil parameters and initial conditions, and cultivar parameters and through perturbations to model state transition equations. The ensemble Kalman filter and the sequential importance resampling filter were tested for the ability to attenuate effects of these types of uncertainty on yield estimates. LAI and theta observations were synthesized according to characteristics of existing remote sensing data, and effects of observation error were tested. Results indicate that the potential for assimilation to improve end-of-season yield estimates is low. Limitations are due to a lack of root zone soil moisture information, error in LAI observations, and a lack of correlation between leaf and grain growth.

  13. Nitrogen Fertilization for Optimizing the Quality and Yield of Shade Grown Cuban Cigar Tobacco: Required Nitrogen Amounts, Application Schedules, Adequate Leaf Nitrogen Levels, and Early Season Diagnostic Tests

    Directory of Open Access Journals (Sweden)

    Borges A

    2014-12-01

    Full Text Available Nitrogen (N fertilizers have a decisive influence on the yield and quality of tobacco. Yield, percentage of plant N, wrapper leaf quality, and nicotine content are all important quality characteristics in tobacco growing. This work is an attempt to provide a tool for optimizing mineral N nutrition for Cuban cigar tobacco, using a strategy that links N supply with leaf N concentration and wrapper yield. Similar approaches developed worldwide have mainly involved Virginia and Burley tobacco types but not Cuban cigar tobacco. The objective of the current work is to identify the effects of fertilizer N levels and timing of application on each of the mentioned quality factors for shade grown Cuban cigar tobacco. Another purpose is to explore the usefulness of a quick method of assessing the N status of plants based on measuring leaf transmission at two different wavelengths (650 and 940 nm. The experiments were done in the main tobacco growing area of Cuba (Vueltabajo. In each experiment, nine separate treatments were used covering different levels and times of fertilizer N application. The same experiment was carried out in three different years (2005-2006, 2006-2007, 2007-2008 but as the results were similar only one set of data is described (2006-2007. The patterns of response to N fertilizer of all four quality measurements, including yield and wrapper leaf quality, were similar in the different replications of the experiments. The optimal fertilizer level was 140-190 kg N/ha (40% applied on days 8-10 after transplanting and 60% on days 18-20 after transplanting. The optimal N concentration of leaves taken at the central foliar level of the middle stalk position was 4.3-4.7% at harvest time. Leaf transmission measurements by means of the SPAD-502 Chlorophyll Meter in the early stages of growth were correlated with leaf chlorophyll and N concentration and provide an excellent guide for predicting Cuban cigar tobacco wrapper leaf yield.

  14. Genotype differences in 13C discrimination between atmosphere and leaf matter match differences in transpiration efficiency at leaf and whole-plant levels in hybrid Populus deltoides x nigra.

    Science.gov (United States)

    Rasheed, Fahad; Dreyer, Erwin; Richard, Béatrice; Brignolas, Franck; Montpied, Pierre; Le Thiec, Didier

    2013-01-01

    (13) C discrimination between atmosphere and bulk leaf matter (Δ(13) C(lb) ) is frequently used as a proxy for transpiration efficiency (TE). Nevertheless, its relevance is challenged due to: (1) potential deviations from the theoretical discrimination model, and (2) complex time integration and upscaling from leaf to whole plant. Six hybrid genotypes of Populus deltoides×nigra genotypes were grown in climate chambers and tested for whole-plant TE (i.e. accumulated biomass/water transpired). Net CO(2) assimilation rates (A) and stomatal conductance (g(s) ) were recorded in parallel to: (1) (13) C in leaf bulk material (δ(13) C(lb) ) and in soluble sugars (δ(13) C(ss) ) and (2) (18) O in leaf water and bulk leaf material. Genotypic means of δ(13) C(lb) and δ(13) C(ss) were tightly correlated. Discrimination between atmosphere and soluble sugars was correlated with daily intrinsic TE at leaf level (daily mean A/g(s) ), and with whole-plant TE. Finally, g(s) was positively correlated to (18) O enrichment of bulk matter or water of leaves at individual level, but not at genotype level. We conclude that Δ(13) C(lb) captures efficiently the genetic variability of whole-plant TE in poplar. Nevertheless, scaling from leaf level to whole-plant TE requires to take into account water losses and respiration independent of photosynthesis, which remain poorly documented. © 2012 Blackwell Publishing Ltd.

  15. Evaluation of the Effect of Irrigation and Fertilization by Drip Fertigation on Tomato Yield and Water Use Efficiency in Greenhouse

    Directory of Open Access Journals (Sweden)

    Wang Xiukang

    2016-01-01

    Full Text Available The water shortage in China, particularly in Northwest China, is very serious. There is, therefore, great potential for improving the water use efficiency (WUE in agriculture, particularly in areas where the need for water is greatest. A two-season (2012 and 2013 study evaluated the effects of irrigation and fertilizer rate on tomato (Lycopersicum esculentum Mill., cv. “Jinpeng 10” growth, yield, and WUE. The fertilizer treatment significantly influenced plant height and stem diameter at 23 and 20 days after transplanting in 2012 and 2013, respectively. As individual factors, irrigation and fertilizer significantly affected the leaf expansion rate, but irrigation × fertilizer had no statistically significant effect on the leaf growth rate at 23 days after transplanting in 2012. Dry biomass accumulation was significantly influenced by fertilizer in both years, but there was no significant difference in irrigation treatment in 2012. Our study showed that an increased irrigation level increased the fruit yield of tomatoes and decreased the WUE. The fruit yield and WUE increased with the increased fertilizer rate. WUE was more sensitive to irrigation than to fertilization. An irrigation amount of 151 to 208 mm and a fertilizer amount of 454 to 461 kg·ha−1 (nitrogen fertilizer, 213.5–217 kg·ha−1; phosphate fertilizer, 106.7–108 kg·ha−1; and potassium fertilizer, 133.4–135.6 kg·ha−1 were recommended for the drip fertigation of tomatoes in greenhouse.

  16. Grain Yield and Water Use Efficiency of Five Sorghum Cultivars under Different Irrigation Regimes in Kerman

    Directory of Open Access Journals (Sweden)

    H Vahidi

    2016-02-01

    Full Text Available Introduction Reduction of the forage and grain yield of sorghum genotypes under different levels of deficit irrigation has been reported. The plants that have higher water use efficiency (WUE, have a better chance of survival in arid regions. On average, WUE of sorghum in clay, loamy soil has been reported equal to 1.46 kg m-3. Effects of drought stress and different levels of nitrogen on yield of two cultivars of sorghum were investigated and results showed significant effects on plant height, leaf area index, fresh and dry weight of leaf, dry weight of stem and forage yield. The purpose of this research is to investigate the effect of deficit irrigation on grain yield and WUE of sorghum cultivars in Kerman. Materials and Methods This study has been conducted in the research station of Shahid Bahonar University of Kerman with 56o 58' E longitude, 30o 15' N latitude and 1753.8 altitudes. According to the regional information from 1952 to 2005, the average temperature is 17.1 oC, the average rainfall is 154.1 mm, the average annual relative humidity is 32%. The climate of Kerman according to De Martonne method can be classified as semiarid. The experimental design was split-plot based on RCBD with three replications. Three levels of irrigation (after 50, 80 and 110 mm evaporation from class A pan were assigned to the main plots and the five sub-plots of sorghum cultivars (Speedfeed, Pegah, Payam, Sepideh and Kimia. On the 20th of May all sorghum cultivars were planted at the distance of 10 cm from each other on ridges. On the 7th of October, with considering margins, four square meters of the two middle lines were selected to determine the grain and biological yield. The samples were weighed with a digital scale and heated for 48 hours in the degree of 75 oC-and then the dry weight of each samples were measured again. Finally, the data were analyzed by SAS software (v. 9.1. Comparision of the averages attributes was performed using, Duncan

  17. Varying plant density and harvest time to optimize cowpea leaf yield and nutrient content

    Science.gov (United States)

    Ohler, T. A.; Nielsen, S. S.; Mitchell, C. A.

    1996-01-01

    Plant density and harvest time were manipulated to optimize vegetative (foliar) productivity of cowpea [Vigna unguiculata (L.) Walp.] canopies for future dietary use in controlled ecological life-support systems as vegetables or salad greens. Productivity was measured as total shoot and edible dry weights (DW), edible yield rate [(EYR) grams DW per square meter per day], shoot harvest index [(SHI) grams DW per edible gram DW total shoot], and yield-efficiency rate [(YER) grams DW edible per square meter per day per grams DW nonedible]. Cowpeas were grown in a greenhouse for leaf-only harvest at 14, 28, 42, 56, 84, or 99 plants/m2 and were harvested 20, 30, 40, or 50 days after planting (DAP). Shoot and edible dry weights increased as plant density and time to harvest increased. A maximum of 1189 g shoot DW/m2 and 594 g edible DW/m2 were achieved at an estimated plant density of 85 plants/m2 and harvest 50 DAP. EYR also increased as plant density and time to harvest increased. An EYR of 11 g m-2 day-1 was predicted to occur at 86 plants/m2 and harvest 50 DAP. SHI and YER were not affected by plant density. However, the highest values of SHI (64%) and YER (1.3 g m-2 day-1 g-1) were attained when cowpeas were harvested 20 DAP. The average fat and ash contents [dry-weight basis (dwb)] of harvested leaves remained constant regardless of harvest time. Average protein content increased from 25% DW at 30 DAP to 45% DW at 50 DAP. Carbohydrate content declined from 50% DW at 30 DAP to 45% DW at 50 DAP. Total dietary fiber content (dwb) of the leaves increased from 19% to 26% as time to harvest increased from 20 to 50 days.

  18. Yield efficiency for nine apple cultivars grafted on two rootstocks

    Directory of Open Access Journals (Sweden)

    João Caetano Fioravanço

    Full Text Available ABSTRACT: Currently, using smaller trees is one of the most important trends in apple cultivation. It is expected that reduced size plants produce lower amount of fruit, but with high yield and yield efficiency. The aim of this study was to evaluate the yield efficiency (YE of nine apple tree cultivars, grafted on two rootstocks, from the second to the seventh year after planting. The YE indexes oscillated from one to the other year, regardless of rootstock. Correlations between YE and yield per tree and between YE and trunk cross sectional area (TCSA confirmed that efficiency can be increased by the production increment or by the plant's vigor reduction. The usefulness of cumulative YE (ƩYE is highlighted to compare apple tree cultivars after the third year of production. The highest ƩYE indexes were observed for 'Royal Gala' and 'Baigent', on M-9 rootstock, and for 'Gala Real' and 'Maxi-Gala', on Marubakaido/M-9 rootstock.

  19. Growth and Nutrient Use Efficiencies of Yams (Dioscorea spp. Grown in Two Contrasting Soils of West Africa

    Directory of Open Access Journals (Sweden)

    Lucien N'Guessan Diby

    2011-01-01

    Full Text Available Fertilization is an important management strategy of yams (Dioscorea spp. especially when grown in degraded soils. A field study evaluated the leaf numbers, leaf area indices, crop growth, yields, and nitrogen (N and potassium (K use efficiencies of D. alata and D. rotundata in Côte d'Ivoire when grown in two contrasting soils with and without fertilizer. D. alata had a lower number of leaves per vine, although leaf area indices were higher, and the leaves were retained for a longer period than in D. rotundata. In all situations, the yields of D. alata were significantly higher, and fertilizers promoted growth of shoots, roots, tubers, and, thus, final yields especially in the low fertile savanna soil. The beneficial impact of fertilizer on yields was significantly lower in the fertile forest soils. The nutrient use agronomic efficiencies indicated the impact of both N and K in promoting yields especially under nonfertilized conditions.

  20. Control of Growth Efficiency in Young Plantation Loblolly Pine and Sweetgum through Irrigation and Fertigation Enhancement of Leaf Carbon Gain; FINAL

    International Nuclear Information System (INIS)

    L. Samuelson

    1999-01-01

    The overall objective of this study was to determine if growth efficiency of young plantation loblolly pine and sweetgum can be maintained by intensive forest management and whether increased carbon gain is the mechanism controlling growth efficiency response to resource augmentation. Key leaf physiological processes were examined over two growing seasons in response to irrigation, fertigation (irrigation with a fertilizer solution), and fertigation plus pest control (pine only). Although irrigation improved leaf net photosynthesis in pine and decreased stomatal sensitivity to vapor pressure deficit in sweetgum, no consistent physiological responses to fertigation were detected in either species. After 4 years of treatment, a 3-fold increase in woody net primary productivity was observed in both species in response to fertigation. Trees supplemented with fertigation and fertigation plus pest control exhibited the largest increases in growth and biomass. Furthermore, growth efficiency was maintained by fertigation and fertigation plus pest control, despite large increases in crown development and self-shading. Greater growth in response to intensive culture was facilitated by significant gains in leaf mass and whole tree carbon gain rather than detectable increases in leaf level processes. Growth efficiency was not maintained by significant increases in leaf level carbon gain but was possibly influenced by changes in carbon allocation to root versus shoot processes

  1. Radiation utilization efficiency, nitrogen uptake and modeling crop growth and yield of rainfed rice under different nitrogen rates

    International Nuclear Information System (INIS)

    Gouranga, Kar; Ashwani Kumar; Mohapatra, Sucharita

    2014-01-01

    Optimum utilization of photosynthetically active radiation (PAR) along with proper nitrogen (N) management for sustainable rice production is still a promising management recommendation for sustainable rainfed rice cultivation in eastern India. The objective of this investigation was to study radiation utilization efficiency (RUE), N uptake and modeling growth and productivity of wet/rainy season rice (cv. Lalat and Gayatri) under 0, 50, 90, 120 and 150 kg ha -1 N application. Results showed that N rates significantly affected plant biomass, leaf area index (LAI), biological yield (straw and grain yield) and N uptake for both the varieties. The intercepted photosynthetically active radiation (IPAR) and spectral reflectance based vegetation indices (IR/R, NDVI) were also different between two varieties and among N rates. Higher rate of N increased the RUE significantly; averaged over years and varieties, mean values of RUE were 1.35, 1.70, 2.01, 2.15 and 2.17 g MJ -1 under 0, 50, 90, 120 and 150 kg N ha -1 , respectively. Though crop growth, yield, N uptake and RUE were higher at 150 kg N ha -1 but the results were at par with 120 kg N ha -1 . Agronomic N use efficiency (ANUE) was also low at 150 kg N ha -1 . The DSSAT v 4.5 model was applied to simulate crop growth, yield and phenology of the crop under different N rates. Model performance was found to be poor at low N rates (0, 50 kg N ha -1 ), but the model performed fairly well at higher N rates (90 kg ha -1 and above). (author)

  2. Contribution of Nitrogen Uptake and Retranslocation during Reproductive Growth to the Nitrogen Efficiency of Winter Oilseed-Rape Cultivars (Brassica napus L. Differing in Leaf Senescence

    Directory of Open Access Journals (Sweden)

    Fabian Koeslin-Findeklee

    2016-01-01

    Full Text Available Genotypic variation in N efficiency defined as high grain yield under limited nitrogen (N supply of winter oilseed-rape line-cultivars has been predominantly attributed to N uptake efficiency (NUPT through maintained N uptake during reproductive growth related to functional stay-green. For investigating the role of stay-green, N retranslocation and N uptake during the reproductive phase for grain yield formation, two line cultivars differing in N starvation-induced leaf senescence were grown in a field experiment without mineral N (N0 and with 160 kg N·ha−1 (N160. Through frequent harvests from full flowering until maturity N uptake, N utilization and apparent N remobilization from vegetative plant parts to the pods could be calculated. NUPT proved being more important than N utilization efficiency (NUE for grain yield formation under N-limiting (N0 conditions. For cultivar differences in N efficiency, particularly N uptake during flowering (NUPT and biomass allocation efficiency (HI to the grains, were decisive. Both crop traits were related to delayed senescence of the older leaves. Remobilization of N particularly from stems and leaves was more important for pod N accumulation than N uptake after full flowering. Pod walls (high N concentrations and stems (high biomass mainly contributed to the crop-residue N at maturity. Decreasing the crop-inherent high N budget surplus of winter oilseed-rape requires increasing the low N remobilization efficiency particularly of pod-wall N to the grains. Addressing this conclusion, multi-year and -location field experiments with an extended range of cultivars including hybrids are desirable.

  3. Do soil organic carbon levels affect potential yields and nitrogen use efficiency?

    DEFF Research Database (Denmark)

    Oelofse, Myles; Markussen, Bo; Knudsen, Leif

    2015-01-01

    Soil organic carbon (SOC) is broadly recognised as an important parameter affecting soil quality, and can therefore contribute to improving a number of soil properties that influence crop yield. Previous research generally indicates that soil organic carbon has positive effects on crop yields......, the yield with no fertiliser N application and the N use efficiency would be positively affected by SOC level. A statistical model was developed to explore relationships between SOC and potential yield, yields at zero N application and N use efficiency (NUE). The model included a variety of variables...

  4. Enhanced leaf photosynthesis as a target to increase grain yield: insights from transgenic rice lines with variable Rieske FeS protein content in the cytochrome b6 /f complex.

    Science.gov (United States)

    Yamori, Wataru; Kondo, Eri; Sugiura, Daisuke; Terashima, Ichiro; Suzuki, Yuji; Makino, Amane

    2016-01-01

    Although photosynthesis is the most important source for biomass and grain yield, a lack of correlation between photosynthesis and plant yield among different genotypes of various crop species has been frequently observed. Such observations contribute to the ongoing debate whether enhancing leaf photosynthesis can improve yield potential. Here, transgenic rice plants that contain variable amounts of the Rieske FeS protein in the cytochrome (cyt) b6 /f complex between 10 and 100% of wild-type levels have been used to investigate the effect of reductions of these proteins on photosynthesis, plant growth and yield. Reductions of the cyt b6 /f complex did not affect the electron transport rates through photosystem I but decreased electron transport rates through photosystem II, leading to concomitant decreases in CO2 assimilation rates. There was a strong control of plant growth and grain yield by the rate of leaf photosynthesis, leading to the conclusion that enhancing photosynthesis at the single-leaf level would be a useful target for improving crop productivity and yield both via conventional breeding and biotechnology. The data here also suggest that changing photosynthetic electron transport rates via manipulation of the cyt b6 /f complex could be a potential target for enhancing photosynthetic capacity in higher plants. © 2015 John Wiley & Sons Ltd.

  5. Light- and water-use efficiency model synergy: a revised look at crop yield estimation for agricultural decision-making

    Science.gov (United States)

    Marshall, M.; Tu, K. P.

    2015-12-01

    Large-area crop yield models (LACMs) are commonly employed to address climate-driven changes in crop yield and inform policy makers concerned with climate change adaptation. Production efficiency models (PEMs), a class of LACMs that rely on the conservative response of carbon assimilation to incoming solar radiation absorbed by a crop contingent on environmental conditions, have increasingly been used over large areas with remote sensing spectral information to improve the spatial resolution of crop yield estimates and address important data gaps. Here, we present a new PEM that combines model principles from the remote sensing-based crop yield and evapotranspiration (ET) model literature. One of the major limitations of PEMs is that they are evaluated using data restricted in both space and time. To overcome this obstacle, we first validated the model using 2009-2014 eddy covariance flux tower Gross Primary Production data in a rice field in the Central Valley of California- a critical agro-ecosystem of the United States. This evaluation yielded a Willmot's D and mean absolute error of 0.81 and 5.24 g CO2/d, respectively, using CO2, leaf area, temperature, and moisture constraints from the MOD16 ET model, Priestley-Taylor ET model, and the Global Production Efficiency Model (GLOPEM). A Monte Carlo simulation revealed that the model was most sensitive to the Enhanced Vegetation Index (EVI) input, followed by Photosynthetically Active Radiation, vapor pressure deficit, and air temperature. The model will now be evaluated using 30 x 30m (Landsat resolution) biomass transects developed in 2011 and 2012 from spectroradiometric and other non-destructive in situ metrics for several cotton, maize, and rice fields across the Central Valley. Finally, the model will be driven by Daymet and MODIS data over the entire State of California and compared with county-level crop yield statistics. It is anticipated that the new model will facilitate agro-climatic decision-making in

  6. Photosynthetic properties of erect leaf maize inbred lines as the efficient photo-model in breeding and seed production

    Directory of Open Access Journals (Sweden)

    Radenović Čedomir N.

    2003-01-01

    Full Text Available The initial idea of this study was a hypothesis that erect leaf maize inbred lines were characterized by properties of an efficient photo-model and that as such were very desirable in increasing the number of plants per area unit (plant density in the process of contemporary selection and seed production. The application of a non-invasive bioluminescence-photosynthetic method, suitable for the efficiency estimation of the photo-model, verified the hypothesis. Obtained photosynthetic properties of observed erect leaf maize inbred lines were based on the effects and characteristics of thermal processes of delayed chlorophyll fluorescence occurring in their thylakoid membranes. The temperature dependence of the delayed chlorophyll fluorescence intensity phase transitions (critical temperatures in the thylakoid membranes and activation energy are the principal parameters of the thermal processes. Based on obtained photosynthetic properties it is possible to select erect leaf maize inbred lines that are resistant and tolerant to high and very high temperatures, as well as, to drought. They could be good and efficient photo-models wherewith.

  7. CO₂ enrichment can produce high red leaf lettuce yield while increasing most flavonoid glycoside and some caffeic acid derivative concentrations.

    Science.gov (United States)

    Becker, Christine; Kläring, Hans-Peter

    2016-05-15

    Carbon dioxide (CO2) enrichment is a common practice in greenhouses to increase crop yields up to 30%. Yet, reports on the effect on foliar phenolic compounds vary. We studied the effect on two red leaf lettuce cultivars, grown for 25 days in growth chambers at CO2 concentrations of 200 or 1,000 ppm, with some plants exchanged between treatments after 11 days. As expected, head mass increased with higher CO2 concentration. Regression analysis, corrected for head mass, showed increased concentrations of most flavonoid glycosides at high CO2 concentrations while only some caffeic acid derivatives were increased, and not uniformly in both cultivars. Sugar concentrations increased with CO2 concentration. Generally, conditions in the 10 days before harvest determined concentrations. We suspect that phenolic compounds were mainly accumulated because plenty of precursors were available. The results indicate that CO2 enrichment can result in high yields of red leaf lettuce rich in phenolic compounds. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. The effect of plant growth promoting rhizobacteria, nitrogen and phosphorus on relative agronomic efficiency of fertilizers, growth parameters and yield of wheat (Triticum aestivum L. cultivar N-80-19 in Sari

    Directory of Open Access Journals (Sweden)

    Z. Saber

    2016-05-01

    Full Text Available In order to evaluate the efficiency of plant growth promoting rhizobacteria (PGPR plus nitrogen and phosphorous chemical fertilizers on relative agronomic efficiency of P and N fertilizers and some agronomic parameters of wheat (Triticum aestivum L. cultivar N-80-19, an experiment was conducted at Sari Agricultural Sciences and Natural Resources University during growing season of 2008-2009. Experiment was arranged in split-split plot based on randomized complete block design with three levels (0, 25 and 50 kg.ha-1 and sub-plots were considered PGPR at four levels (control, inoculation with nitrogen fixing bacteria (PFB, phosphate solubilizing bacteria (PSB and dual inoculation with PFB and PSB with three replications. Results showed that the application of biofertilizers significantly increased relative agronomic efficiency of N and P fertilizers, spike number, plant height, flag leaf area, grain yield and grain weight of wheat. Application of biofertilizers increased wheat grain yield as much as 46.6% as compared to control. Double inoculation of biofertilizers improved relative agronomic efficiency of fertilizers by 58.4 and 76.5% as compared to control, respectively. Integrated treatments showed higher performance compared to separate treatments. Generally, biofertilizers with low levels of P and N fertilizers significantly improved yield components of wheat without any reduction in yield related parameters.

  9. Path Analysis of Grain Yield and Yield Components and Some Agronomic Traits in Bread Wheat

    Directory of Open Access Journals (Sweden)

    Mohsen Janmohammadi

    2014-01-01

    Full Text Available Development of new bread wheat cultivars needs efficient tools to monitor trait association in a breeding program. This investigation was aimed to characterize grain yield components and some agronomic traits related to bread wheat grain yield. The efficiency of a breeding program depends mainly on the direction of the correlation between different traits and the relative importance of each component involved in contributing to grain yield. Correlation and path analysis were carried out in 56 bread wheat genotypes grown under field conditions of Maragheh, Iran. Observations were recorded on 18 wheat traits and correlation coefficient analysis revealed grain yield was positively correlated with stem diameter, spike length, floret number, spikelet number, grain diameter, grain length and 1000 seed weight traits. According to the variance inflation factor (VIF and tolerance as multicollinearity statistics, there are inconsistent relationships among the variables and all traits could be considered as first-order variables (Model I with grain yield as the response variable due to low multicollinearity of all measured traits. In the path coefficient analysis, grain yield represented the dependent variable and the spikelet number and 1000 seed weight traits were the independent ones. Our results indicated that the number of spikelets per spikes and leaf width and 1000 seed weight traits followed by the grain length, grain diameter and grain number per spike were the traits related to higher grain yield. The above mentioned traits along with their indirect causal factors should be considered simultaneously as an effective selection criteria evolving high yielding genotype because of their direct positive contribution to grain yield.

  10. Leaf N resorption efficiency and litter N mineralization rate have a genotypic tradeoff in a silver birch population.

    Science.gov (United States)

    Mikola, Juha; Silfver, Tarja; Paaso, Ulla; Possen, Boy J M H; Rousi, Matti

    2018-02-07

    Plants enhance N use efficiency by resorbing N from senescing leaves. This can affect litter N mineralization rate due to the C:N-ratio requirements of microbial growth. We examined genotypic links between leaf N resorption and litter mineralization by collecting leaves and litter from 19 Betula pendula genotypes and following the N release of litter patches on forest ground. We found significant genotypic variation for N resorption efficiency, litter N concentration, cumulative three-year patch N-input and litter N release with high broad-sense heritabilities (H 2  = 0.28-0.65). The genotype means of N resorption efficiency varied from 46% to 65% and correlated negatively with the genotype means of litter N concentration, cumulative patch N-input and litter N release. NH 4 + yield under patches had a positive genotypic correlation with the cumulative patch N-input. During the first year of litter decomposition, genotypes varied from N immobilization (max 2.71 mg/g dry litter) to N release (max 1.41 mg/g dry litter), creating a genotypic tradeoff between the N conserved by resorption and the N available for root uptake during the growing season. We speculate that this tradeoff is one likely reason for the remarkably wide genotypic range of N resorption efficiencies in our birch population. © 2018 by the Ecological Society of America.

  11. Design of a size-efficient tunable metamaterial absorber based on leaf-shaped cell at near-infrared regions

    Science.gov (United States)

    Huang, Hailong; Xia, Hui; Xie, Wenke; Guo, Zhibo; Li, Hongjian

    2018-06-01

    A size-efficient tunable metamaterial absorber (MA) composed of metallic leaf-shaped cell, graphene layer, silicon substrate, and bottom metal film is investigated theoretically and numerically at near-infrared (NIR) regions. Simulation results reveal that the single-band high absorption of 91.9% is obtained at 1268.7 nm. Further results show that the single-band can be simply changed into dual-band high absorption by varying the geometric parameters of top metallic layer at same wavelength regions, yielding two high absorption coefficients of 96.6% and 95.3% at the wavelengths of 1158.7 nm and 1323.6 nm, respectively. And the effect of related geometric parameter on dual-band absorption intensities is also investigated to obtain the optimized one. The peak wavelength can be tuned via modifying the Fermi energy of the graphene layer through controlling the external gate voltage. The work shows that the proposed strategy can be applied to other design of the dual-band structure at infrared regions.

  12. Global parameterization and validation of a two-leaf light use efficiency model for predicting gross primary production across FLUXNET sites

    DEFF Research Database (Denmark)

    Zhou, Yanlian; Wu, Xiaocui; Ju, Weimin

    2015-01-01

    Light use efficiency (LUE) models are widely used to simulate gross primary production (GPP). However, the treatment of the plant canopy as a big leaf by these models can introduce large uncertainties in simulated GPP. Recently, a two-leaf light use efficiency (TL-LUE) model was developed...... to simulate GPP separately for sunlit and shaded leaves and has been shown to outperform the big-leaf MOD17 model at six FLUX sites in China. In this study we investigated the performance of the TL-LUE model for a wider range of biomes. For this we optimized the parameters and tested the TL-LUE model using...... data from 98 FLUXNET sites which are distributed across the globe. The results showed that the TL-LUE model performed in general better than the MOD17 model in simulating 8 day GPP. Optimized maximum light use efficiency of shaded leaves (epsilon(msh)) was 2.63 to 4.59 times that of sunlit leaves...

  13. Improvements in the transformation of Arabidopsis thaliana C24 leaf-discs by Agrobacterium tumefaciens

    DEFF Research Database (Denmark)

    van der Graaff, Eric; Hooykaas, P J

    1996-01-01

    We report here an efficient Arabidopsis leafdisc transformation protocol yielding an average transformation frequency of 1.6 transgenic shoots per leaf explant 4 weeks after the bacterial infection period. Subsequent cultivation in vitro is such that a high percentage (85-90%) of the primary...... transformants produces seeds with an average seed yield of 100-300 seeds per plant. This improved transformation protocol yields mainly (70%) transformants segregating for a single T-DNA locus of which 68% actually contain one T-DNA insert. The objective is to generate a pool of independent transformants...

  14. Optimising nitrogen in order to improve the efficiency, eco-physiology, yield and quality on one cultivar of durum wheat

    Directory of Open Access Journals (Sweden)

    Luigi Tedone

    2014-04-01

    Full Text Available A 3-year field experiment was carried out in southern Italy to evaluate the effect of different combinations of nitrogen (N fertilizer rates (0, 55, 90, 135 kg ha–1, time of application (sowing, tillering, stem elongation and number of nitrogen applications on durum wheat (Triticum turgidum L., var. durum. A total of eight different combinations - in terms of quantity and time of application - were arranged in a randomized complete block design with four replications. Soil plant analysis development was analysed along with leaf area index, grain and straw yield, plant height, plant lodging, thousand-kernel weight, non-vitreous kernels, shrunken and discarded kernels, hectolitre weight, grain protein content, and sodium dodecylsulfate sedimentation. Nitrogen contents of soil, grain and straw were measured in order to assess nitrogen efficiency. The results showed the positive effect of increased nitrogen dosages of 90 and 135 kg ha–1. The optimization of nitrogen administration increased by splitting the nitrogen into three application times, as shown by the eco-physiological, productive and qualitative parameters, and the nitrogen efficiency parameters measured (N application efficiency and N recovery fraction.

  15. Effects of delaying transplanting on agronomic traits and grain yield of rice under mechanical transplantation pattern.

    Directory of Open Access Journals (Sweden)

    Qihua Liu

    Full Text Available A delay in the mechanical transplantation (MT of rice seedlings frequently occurs in Huanghuai wheat-rice rotation cropping districts of China, due to the late harvest of wheat, the poor weather conditions and the insufficiency of transplanters, missing the optimum transplanting time and causing seedlings to age. To identify how delaying transplanting rice affects the agronomic characteristics including the growth duration, photosynthetic productivity and dry matter remobilization efficiency and the grain yield under mechanical transplanting pattern, an experiment with a split-plot design was conducted over two consecutive years. The main plot includes two types of cultivation: mechanical transplanting and artificial transplanting (AT. The subplot comprises four japonica rice cultivars. The results indicate that the rice jointing, booting, heading and maturity stages were postponed under MT when using AT as a control. The tiller occurrence number, dry matter weight per tiller, accumulative dry matter for the population, leaf area index, crop growth rate, photosynthetic potential, and dry matter remobilization efficiency of the leaf under MT significantly decreased compared to those under AT. In contrast, the reduction rate of the leaf area during the heading-maturity stage was markedly enhanced under MT. The numbers of effective panicles and filled grains per panicle and the grain yield significantly decreased under MT. A significant correlation was observed between the dry matter production, remobilization and distribution characteristics and the grain yield. We infer that, as with rice from old seedlings, the decrease in the tiller occurrence, the photosynthetic productivity and the assimilate remobilization efficiency may be important agronomic traits that are responsible for the reduced grain yield under MT.

  16. Phenotyping of field-grown wheat in the UK highlights contribution of light response of photosynthesis and flag leaf longevity to grain yield.

    Science.gov (United States)

    Carmo-Silva, Elizabete; Andralojc, P John; Scales, Joanna C; Driever, Steven M; Mead, Andrew; Lawson, Tracy; Raines, Christine A; Parry, Martin A J

    2017-06-15

    Improving photosynthesis is a major target for increasing crop yields and ensuring food security. Phenotyping of photosynthesis in the field is critical to understand the limits to crop performance in agricultural settings. Yet, detailed phenotyping of photosynthetic traits is relatively scarce in field-grown wheat, with previous studies focusing on narrow germplasm selections. Flag leaf photosynthetic traits, crop development, and yield traits were compared in 64 field-grown wheat cultivars in the UK. Pre-anthesis and post-anthesis photosynthetic traits correlated significantly and positively with grain yield and harvest index (HI). These traits included net CO2 assimilation measured at ambient CO2 concentrations and a range of photosynthetic photon flux densities, and traits associated with the light response of photosynthesis. In most cultivars, photosynthesis decreased post-anthesis compared with pre-anthesis, and this was associated with decreased Rubisco activity and abundance. Heritability of photosynthetic traits suggests that phenotypic variation can be used to inform breeding programmes. Specific cultivars were identified with traits relevant to breeding for increased crop yields in the UK: pre-anthesis photosynthesis, post-anthesis photosynthesis, light response of photosynthesis, and Rubisco amounts. The results indicate that flag leaf longevity and operating photosynthetic activity in the canopy can be further exploited to maximize grain filling in UK bread wheat. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. Efficient Method for Calculating the Composite Stiffness of Parabolic Leaf Springs with Variable Stiffness for Vehicle Rear Suspension

    Directory of Open Access Journals (Sweden)

    Wen-ku Shi

    2016-01-01

    Full Text Available The composite stiffness of parabolic leaf springs with variable stiffness is difficult to calculate using traditional integral equations. Numerical integration or FEA may be used but will require computer-aided software and long calculation times. An efficient method for calculating the composite stiffness of parabolic leaf springs with variable stiffness is developed and evaluated to reduce the complexity of calculation and shorten the calculation time. A simplified model for double-leaf springs with variable stiffness is built, and a composite stiffness calculation method for the model is derived using displacement superposition and material deformation continuity. The proposed method can be applied on triple-leaf and multileaf springs. The accuracy of the calculation method is verified by the rig test and FEA analysis. Finally, several parameters that should be considered during the design process of springs are discussed. The rig test and FEA analytical results indicate that the calculated results are acceptable. The proposed method can provide guidance for the design and production of parabolic leaf springs with variable stiffness. The composite stiffness of the leaf spring can be calculated quickly and accurately when the basic parameters of the leaf spring are known.

  18. Overproduction of abscisic acid in tomato increases transpiration efficiency and root hydraulic conductivity and influences leaf expansion.

    Science.gov (United States)

    Thompson, Andrew J; Andrews, John; Mulholland, Barry J; McKee, John M T; Hilton, Howard W; Horridge, Jon S; Farquhar, Graham D; Smeeton, Rachel C; Smillie, Ian R A; Black, Colin R; Taylor, Ian B

    2007-04-01

    Overexpression of genes that respond to drought stress is a seemingly attractive approach for improving drought resistance in crops. However, the consequences for both water-use efficiency and productivity must be considered if agronomic utility is sought. Here, we characterize two tomato (Solanum lycopersicum) lines (sp12 and sp5) that overexpress a gene encoding 9-cis-epoxycarotenoid dioxygenase, the enzyme that catalyzes a key rate-limiting step in abscisic acid (ABA) biosynthesis. Both lines contained more ABA than the wild type, with sp5 accumulating more than sp12. Both had higher transpiration efficiency because of their lower stomatal conductance, as demonstrated by increases in delta(13)C and delta(18)O, and also by gravimetric and gas-exchange methods. They also had greater root hydraulic conductivity. Under well-watered glasshouse conditions, mature sp5 plants were found to have a shoot biomass equal to the wild type despite their lower assimilation rate per unit leaf area. These plants also had longer petioles, larger leaf area, increased specific leaf area, and reduced leaf epinasty. When exposed to root-zone water deficits, line sp12 showed an increase in xylem ABA concentration and a reduction in stomatal conductance to the same final levels as the wild type, but from a different basal level. Indeed, the main difference between the high ABA plants and the wild type was their performance under well-watered conditions: the former conserved soil water by limiting maximum stomatal conductance per unit leaf area, but also, at least in the case of sp5, developed a canopy more suited to light interception, maximizing assimilation per plant, possibly due to improved turgor or suppression of epinasty.

  19. Environmental modification of yield and food composition of cowpea and leaf lettuce

    Science.gov (United States)

    Mitchell, Cary A.; Nielsen, Suzanne S.; Bubenheim, David L.

    1990-01-01

    Cowpea (Vigna unguiculata (L.) Walp.) and leaf lettuce (Lactuca sativa L.) are candidate species to provide ligume protein and starch or serve as a salad base for a nutritionally balanced and psychologically satisfying vegetarian diet in the Controlled Ecology Life Support System (CELSS). Various nutritional parameters are reported. Hydroponic leaf lettuce grew best under CO2 enrichment and photosynthetic photon flux (PPF) enhancement. Leaf protein content reached 36 percent with NH4(+) + NO3 nutrition; starch and free sugar content was as high as 7 or 8.4 percent of DW, respectively, for high PPF/CO2 enriched environments.

  20. Simple models for predicting leaf area of mango (Mangifera indica L.

    Directory of Open Access Journals (Sweden)

    Maryam Ghoreishi

    2012-01-01

    Full Text Available Mango (Mangifera indica L., one of the most popular tropical fruits, is cultivated in a considerable part of southern Iran. Leaf area is a valuable parameter in mango research, especially plant physiological and nutrition field. Most of available methods for estimating plant leaf area are difficult to apply, expensive and destructive which could in turn destroy the canopy and consequently make it difficult to perform further tests on the same plant. Therefore, a non-destructive method which is simple, inexpensive, and could yield an accurate estimation of leaf area will be a great benefit to researchers. A regression analysis was performed in order to determine the relationship between the leaf area and leaf width, leaf length, dry and fresh weight. For this purpose 50 mango seedlings of local selections were randomly took from a nursery in the Hormozgan province, and different parts of plants were separated in laboratory. Leaf area was measured by different method included leaf area meter, planimeter, ruler (length and width and the fresh and dry weight of leaves were also measured. The best regression models were statistically selected using Determination Coefficient, Maximum Error, Model Efficiency, Root Mean Square Error and Coefficient of Residual Mass. Overall, based on regression equation, a satisfactory estimation of leaf area was obtained by measuring the non-destructive parameters, i.e. number of leaf per seedling, length of the longest and width of widest leaf (R2 = 0.88 and also destructive parameters, i.e. dry weight (R2 = 0.94 and fresh weight (R2= 0.94 of leaves.

  1. [Effects of different colored plastic film mulching and planting density on dry matter accumulation and yield of spring maize.

    Science.gov (United States)

    Zhang, Lin Lin; Sun, Shi Jun; Chen, Zhi Jun; Jiang, Hao; Zhang, Xu Dong; Chi, Dao Cai

    2018-01-01

    In order to investigate the effect of different colored plastic film mulching and planting density on spring maize dry matter accumulation and yield in the rain-fed area of the Northeast China, a complete combination field experiment which was comprised by three types of mulching (non-mulching, transparent plastic film mulching and black plastic film mulching) and five densities (60000, 67500, 75000, 82500 and 90000 plants·hm -2 ), was conducted to analyze the water and heat effect, dry matter accumulation and yield of spring maize (Liangyu 99). The results showed that, compared with the other mulching treatments, the black plastic film mulching treatment significantly increased the maize dry matter accumulation and maize biomass by 3.2%-8.2%. In mature stage, the biomass increased firstly and then decreased with the increasing plant density. When planting density was 82500 plants·hm -2 , the biomass was the highest, which was 5.2%-28.3% higher than that of other plant density treatments. The mean soil temperature in prophase of transparent plastic film mulching treatment was 0.4-2.7 ℃ higher than that of other treatments, which accelerated the maize growth process and augmented the dry matter transportation amount (T), dry matter transportation efficiency (TE) and contribution rate of dry matter transportation to the grain yield (TC) of maize stalk and leaf. The T, TE, TC of leaf and leaf-stalk under 60000 plants·hm -2 treatment were the highest. The highest T, TE, TC of stalk were observed under 75000 plants·hm -2 treatment. In heading period, the water consumption and daily water consumption intensity of maize under the treatment of black film mulching were the largest, which were 9.4%-10.6% and 10.6%-24.5% higher than that of other mulching treatments, respectively. The highest water consumption and daily water consumption intensity were both obtained under 90000 plants·hm -2 treatment, which increased by 6.8%-15.7% and 7.0%-20.0% compared with other

  2. Spring maize yield, soil water use and water use efficiency under plastic film and straw mulches in the Loess Plateau

    Science.gov (United States)

    Lin, Wen; Liu, Wenzhao; Xue, Qingwu

    2016-12-01

    To compare the soil water balance, yield and water use efficiency (WUE) of spring maize under different mulching types in the Loess Plateau, a 7-year field experiment was conducted in the Changwu region of the Loess Plateau. Three treatments were used in this experiment: straw mulch (SM), plastic film mulch (PM) and conventional covering without mulch (CK). Results show that the soil water change of dryland spring maize was as deep as 300 cm depth and hence 300 cm is recommended as the minimum depth when measure the soil water in this region. Water use (ET) did not differ significantly among the treatments. However, grain yield was significantly higher in PM compared with CK. WUE was significantly higher in PM than in CK for most years of the experiment. Although ET tended to be higher in PM than in the other treatments (without significance), the evaporation of water in the fallow period also decreased. Thus, PM is sustainable with respect to soil water balance. The 7-year experiment and the supplemental experiment thus confirmed that straw mulching at the seedling stage may lead to yield reduction and this effect can be mitigated by delaying the straw application to three-leaf stage.

  3. Integrated crop management practices for maximizing grain yield of double-season rice crop

    Science.gov (United States)

    Wang, Depeng; Huang, Jianliang; Nie, Lixiao; Wang, Fei; Ling, Xiaoxia; Cui, Kehui; Li, Yong; Peng, Shaobing

    2017-01-01

    Information on maximum grain yield and its attributes are limited for double-season rice crop grown under the subtropical environment. This study was conducted to examine key characteristics associated with high yielding double-season rice crop through a comparison between an integrated crop management (ICM) and farmers’ practice (FP). Field experiments were conducted in the early and late seasons in the subtropical environment of Wuxue County, Hubei Province, China in 2013 and 2014. On average, grain yield in ICM was 13.5% higher than that in FP. A maximum grain yield of 9.40 and 10.53 t ha-1 was achieved under ICM in the early- and late-season rice, respectively. Yield improvement of double-season rice with ICM was achieved with the combined effects of increased plant density and optimized nutrient management. Yield gain of ICM resulted from a combination of increases in sink size due to more panicle number per unit area and biomass production, further supported by the increased leaf area index, leaf area duration, radiation use efficiency, crop growth rate, and total nitrogen uptake compared with FP. Further enhancement in the yield potential of double-season rice should focus on increasing crop growth rate and biomass production through improved and integrated crop management practices.

  4. Leaf sequencing algorithms for segmented multileaf collimation

    International Nuclear Information System (INIS)

    Kamath, Srijit; Sahni, Sartaj; Li, Jonathan; Palta, Jatinder; Ranka, Sanjay

    2003-01-01

    The delivery of intensity-modulated radiation therapy (IMRT) with a multileaf collimator (MLC) requires the conversion of a radiation fluence map into a leaf sequence file that controls the movement of the MLC during radiation delivery. It is imperative that the fluence map delivered using the leaf sequence file is as close as possible to the fluence map generated by the dose optimization algorithm, while satisfying hardware constraints of the delivery system. Optimization of the leaf sequencing algorithm has been the subject of several recent investigations. In this work, we present a systematic study of the optimization of leaf sequencing algorithms for segmental multileaf collimator beam delivery and provide rigorous mathematical proofs of optimized leaf sequence settings in terms of monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation constraint and leaf interdigitation constraint. Our analytical analysis shows that leaf sequencing based on unidirectional movement of the MLC leaves is as MU efficient as bidirectional movement of the MLC leaves

  5. Leaf sequencing algorithms for segmented multileaf collimation

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, Srijit [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Sahni, Sartaj [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Li, Jonathan [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Palta, Jatinder [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Ranka, Sanjay [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States)

    2003-02-07

    The delivery of intensity-modulated radiation therapy (IMRT) with a multileaf collimator (MLC) requires the conversion of a radiation fluence map into a leaf sequence file that controls the movement of the MLC during radiation delivery. It is imperative that the fluence map delivered using the leaf sequence file is as close as possible to the fluence map generated by the dose optimization algorithm, while satisfying hardware constraints of the delivery system. Optimization of the leaf sequencing algorithm has been the subject of several recent investigations. In this work, we present a systematic study of the optimization of leaf sequencing algorithms for segmental multileaf collimator beam delivery and provide rigorous mathematical proofs of optimized leaf sequence settings in terms of monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation constraint and leaf interdigitation constraint. Our analytical analysis shows that leaf sequencing based on unidirectional movement of the MLC leaves is as MU efficient as bidirectional movement of the MLC leaves.

  6. Effect of Nitrogen Foliar Application on Canola Yield (Brassica napus L. and Nitrogen Efficiency across Different Sowing Dates

    Directory of Open Access Journals (Sweden)

    S Doori

    2016-12-01

    Full Text Available Introduction Between oil seeds, from the quality, quantity and nutrition index point of view, canola has the top level . Because of the solubility of N fertilizers, the time of urea application, is very important and one of the main reasons of the reduction in N application efficiency is utilization of urea in an inappropriate time. By precisely foliar application of nitrogen, the efficiency of nitrogen transformation to the grain will be very high because in this method the leaf is considered the main organ of nitrogen uptake and a low amount of absorbed nitrogen was transferred to the root and entered the soil. The more division of N application in growth stages and in accordance with plant need and foliar application result in increasing nitrogen use efficiency. The delay in sowing will result in the reduction of yield and this is due to low LAI, and thus low radiation absorb in vegetable phase and shorter reproductive phase with high temperature in flowering and subsequent stages that result in low prolific silique and make disorder in transferring stored material to grain. In this experiment using N foliar application to decrease the adverse effect of delay in sowing is objective. Materials and Methods The experiment was conducted in 2013-2014 in Ramin Agriculture and Natural Resource University of Khuzestan. Experiment was conducted as split plots in a randomized complete blocks design with three replications. In this experiment sowing date]optimum sowing (27 November, 17 December and late sowing (30 December [were assigned to main plots and several time of N-foliar application with 5 percent density from urea (20 liter per ha, ]TO (control, T1 (foliar N application in rosette stage, T2 (foliar N application in budding stage, T3 (foliar N application in flowering stage[ were placed in sub-plots in randomized way. Fertilizing was based on the results of soil examination. Therefore, 162 kg ha-1 of pure nitrogen (from resource urea in the way

  7. An investigation of the leaf retention capacity, efficiency and mechanism for atmospheric particulate matter of five greening tree species in Beijing, China.

    Science.gov (United States)

    Liu, Jinqiang; Cao, Zhiguo; Zou, Songyan; Liu, Huanhuan; Hai, Xiao; Wang, Shihua; Duan, Jie; Xi, Benye; Yan, Guangxuan; Zhang, Shaowei; Jia, Zhongkui

    2018-03-01

    Urban trees have the potential to reduce air pollution, but the retention capacity and efficiency of different tree species for atmospheric particulate matter (PM) accumulation and the underlying mechanism hasn't been well understood. To select tree species with high air purification abilities, the supplementing ultrasonic cleaning (UC) procedure was first introduced into the conventional leaf cleaning methods [single water cleaning (WC) or plus brush cleaning (BC)] for eluting the leaf-retained PM. Further updates to the methodology were applied to investigate the retention capacity, efficiency, and mechanism for PM of five typical greening tree species in Beijing, China. Meanwhile, the particle size distribution of PM on the leaves, the PM retention efficiencies of easily removable (ERP), difficult-to-remove (DRP) and totally removable (TRP) particles on the leaf (AE leaf ), and the individual tree scales were estimated. The experimental leaf samples were collected from trees with similar sizes 4 (SDR) and 14days (LDR) after rainfall. When the leaves were cleaned by WC+BC, there was, on average, 29%-46% of the PM remaining on the leaves of different species, which could be removed almost completely if UC was supplemented. From SDR to LDR, the mass of the leaf-retained PM increased greatly, and the particle size distribution changed markedly for all species except for Sophorajaponica. Pinus tabuliformis retains particles with the largest average diameter (34.2μm), followed by Ginkgo biloba (20.5μm), Sabina chinensis (16.4μm), Salix babylonica (16.0μm), and S. japonica (13.1μm). S. japonica and S. chinensis had the highest AE leaf to retain the TRP and ERP of both PM 1 and PM 1-2.5 , respectively. Conversely, S. babylonica and P. tabuliformis could retain both TRP and ERP of PM 2.5-5 and PM 5-10 , and PM >10 and TSP with the highest AE leaf , respectively. In conclusion, our results could be useful in selecting greening tree species with high air purification

  8. Improving carbon dioxide yields and cell efficiencies for ethanol oxidation by potential scanning

    Science.gov (United States)

    Majidi, Pasha; Pickup, Peter G.

    2014-12-01

    An ethanol electrolysis cell with aqueous ethanol supplied to the anode and nitrogen at the cathode has been operated under potential cycling conditions in order to increase the yield of carbon dioxide and thereby increase cell efficiency relative to operation at a fixed potential. At ambient temperature, faradaic yields of CO2 as high as 26% have been achieved, while only transient CO2 production was observed at constant potential. Yields increased substantially at higher temperatures, with maximum values at Pt anodes reaching 45% at constant potential and 65% under potential cycling conditions. Use of a PtRu anode increased the cell efficiency by decreasing the anode potential, but this was offset by decreased CO2 yields. Nonetheless, cycling increased the efficiency relative to constant potential. The maximum yields at PtRu and 80 °C were 13% at constant potential and 32% under potential cycling. The increased yields under cycling conditions have been attributed to periodic oxidative stripping of adsorbed CO, which occurs at lower potentials on PtRu than on Pt. These results will be important in the optimization of operating conditions for direct ethanol fuel cells and for the electrolysis of ethanol to produce clean hydrogen.

  9. Variation of inulin content, inulin yield and water use efficiency for inulin yield in Jerusalem artichoke genotypes under different water regimes

    Science.gov (United States)

    The information on genotypic variation for inulin content, inulin yield and water use efficiency of inulin yield (WUEi) in response to drought is limited. This study was to investigate the genetic variability in inulin content, inulin yield and WUEi of Jerusalem artichoke (Helianthus tuberosus L.) ...

  10. The effect of leaf litter cover on surface runoff and soil erosion in Northern China.

    Directory of Open Access Journals (Sweden)

    Xiang Li

    Full Text Available The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter, four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (p<0.05. Average runoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, p<0.05, and the efficiency in runoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h-1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05 were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (p<0.05 with sediment yield. These results suggest that the protective role of leaf litter in runoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes.

  11. Alkylating efficiency of sodium azide on pod yield, nut size and ...

    African Journals Online (AJOL)

    Mutation has been utilised to improve growth and yield of many food crops, but only little effort has been made to ascertain the nutritional advantages in such improved crops. The present study evaluates the alkylating efficiency of sodium azide of different concentrations on pod yield, nut size and nutritional composition of ...

  12. Thidiazuron: A potent cytokinin for efficient plant regeneration in Himalayan poplar (Populus ciliata Wall. using leaf explants

    Directory of Open Access Journals (Sweden)

    Gaurav Aggarwal

    2012-11-01

    Full Text Available Populus species are important resource for certain branches of industry and have special roles for scientific study on biological and agricultural systems. The present investigation was undertaken with an objective of enhancing the frequency of plant regeneration in Himalayan poplar (Populus ciliata Wall.. The effect of Thiadizuron (TDZ alone and in combination with adenine and α-Naphthalene acetic acid (NAA were studied on the regeneration potential of leaf explants. A high efficiency of shoot regeneration was observed in leaf (80.00% explants on MS basal medium supplemented with 0.024 mg/l TDZ and 79.7 mg/l adenine. Elongation and multiplication of shoots were obtained on Murashige and Skoog (MS basal medium, containing 0.5 mg/l 6. Benzyl aminopurine (BAP + 0.2mg/l Indole 3-acetic acid (IAA + 0.3 mg/l Gibberellic acid (GA3. High frequency root regeneration from in vitro developed shoots was observed on MS basal medium supplemented with 0.10 mg/l Indole 3-butyric acid(IBA. Maximum of the in vitro rooted plantlets were well accomplished to the mixture of sand: soil (1:1 and exhibited similar morphology with the field plants. A high efficiency plant regeneration protocol has been developedfrom leaf explants in Himalayan poplar (Populus ciliata Wall..

  13. Estimation efficiency of usage satellite derived and modelled biophysical products for yield forecasting

    Science.gov (United States)

    Kolotii, Andrii; Kussul, Nataliia; Skakun, Sergii; Shelestov, Andrii; Ostapenko, Vadim; Oliinyk, Tamara

    2015-04-01

    Efficient and timely crop monitoring and yield forecasting are important tasks for ensuring of stability and sustainable economic development [1]. As winter crops pay prominent role in agriculture of Ukraine - the main focus of this study is concentrated on winter wheat. In our previous research [2, 3] it was shown that usage of biophysical parameters of crops such as FAPAR (derived from Geoland-2 portal as for SPOT Vegetation data) is far more efficient for crop yield forecasting to NDVI derived from MODIS data - for available data. In our current work efficiency of usage such biophysical parameters as LAI, FAPAR, FCOVER (derived from SPOT Vegetation and PROBA-V data at resolution of 1 km and simulated within WOFOST model) and NDVI product (derived from MODIS) for winter wheat monitoring and yield forecasting is estimated. As the part of crop monitoring workflow (vegetation anomaly detection, vegetation indexes and products analysis) and yield forecasting SPIRITS tool developed by JRC is used. Statistics extraction is done for landcover maps created in SRI within FP-7 SIGMA project. Efficiency of usage satellite based and modelled with WOFOST model biophysical products is estimated. [1] N. Kussul, S. Skakun, A. Shelestov, O. Kussul, "Sensor Web approach to Flood Monitoring and Risk Assessment", in: IGARSS 2013, 21-26 July 2013, Melbourne, Australia, pp. 815-818. [2] F. Kogan, N. Kussul, T. Adamenko, S. Skakun, O. Kravchenko, O. Kryvobok, A. Shelestov, A. Kolotii, O. Kussul, and A. Lavrenyuk, "Winter wheat yield forecasting in Ukraine based on Earth observation, meteorological data and biophysical models," International Journal of Applied Earth Observation and Geoinformation, vol. 23, pp. 192-203, 2013. [3] Kussul O., Kussul N., Skakun S., Kravchenko O., Shelestov A., Kolotii A, "Assessment of relative efficiency of using MODIS data to winter wheat yield forecasting in Ukraine", in: IGARSS 2013, 21-26 July 2013, Melbourne, Australia, pp. 3235 - 3238.

  14. Study on calibration of neutron efficiency and relative photo-yield of plastic scintillator

    International Nuclear Information System (INIS)

    Peng Taiping; Zhang Chuanfei; Li Rurong; Zhang Jianhua; Luo Xiaobing; Xia Yijun; Yang Zhihua

    2002-01-01

    A method used for the calibration of neutron efficiency and the relative photo yield of plastic scintillator is studied. T(p, n) and D(d, n) reactions are used as neutron resources. The neutron efficiencies and the relative photo yields of plastic scintillators 1421 (40 mm in diameter and 5 mm in thickness) and determined in the neutron energy range of 0.655-5 MeV

  15. Effects of Nutrient Antagonism and Synergism on Yield and Fertilizer Use Efficiency

    NARCIS (Netherlands)

    Rietra, René P.J.J.; Heinen, Marius; Dimkpa, Chistian O.; Bindraban, Prem S.

    2017-01-01

    Interaction among plant nutrients can yield antagonistic or synergistic outcomes that influence nutrient use efficiency. To provide insight on this phenomenon, peer-reviewed articles were selected that quantified the interaction effects of nutrients on crop yield levels. In total 94 articles were

  16. Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China

    Science.gov (United States)

    Xu, Xinpeng; Liu, Xiaoyan; He, Ping; Johnston, Adrian M.; Zhao, Shicheng; Qiu, Shaojun; Zhou, Wei

    2015-01-01

    Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L.) were collected in four maize agro-ecological regions of China, and the optimal management (OPT), farmers’ practice (FP), a series of nutrient omission treatments were used to analyze yield gap, nutrient use efficiency and indigenous nutrient supply by adopting meta-analysis and ANOVA analysis. Across all sites, the average yield gap between OPT and FP was 0.7 t ha-1, the yield response to nitrogen (N), phosphorus (P), and potassium (K) were 1.8, 1.0, and 1.2 t ha-1, respectively. The soil indigenous nutrient supply of N, P, and K averaged 139.9, 33.7, and 127.5 kg ha-1, respectively. As compared to FP, the average recovery efficiency (RE) of N, P, and K with OPT increased by percentage point of 12.2, 5.5, and 6.5, respectively. This study indicated that there would be considerable potential to further improve yield and nutrient use efficiency in China, and will help develop and inform agricultural policies and strategies, while some management measures such as soil, plant and nutrient are necessary and integrate with advanced knowledge and technologies. PMID:26484543

  17. Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China.

    Directory of Open Access Journals (Sweden)

    Xinpeng Xu

    Full Text Available Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L. were collected in four maize agro-ecological regions of China, and the optimal management (OPT, farmers' practice (FP, a series of nutrient omission treatments were used to analyze yield gap, nutrient use efficiency and indigenous nutrient supply by adopting meta-analysis and ANOVA analysis. Across all sites, the average yield gap between OPT and FP was 0.7 t ha-1, the yield response to nitrogen (N, phosphorus (P, and potassium (K were 1.8, 1.0, and 1.2 t ha-1, respectively. The soil indigenous nutrient supply of N, P, and K averaged 139.9, 33.7, and 127.5 kg ha-1, respectively. As compared to FP, the average recovery efficiency (RE of N, P, and K with OPT increased by percentage point of 12.2, 5.5, and 6.5, respectively. This study indicated that there would be considerable potential to further improve yield and nutrient use efficiency in China, and will help develop and inform agricultural policies and strategies, while some management measures such as soil, plant and nutrient are necessary and integrate with advanced knowledge and technologies.

  18. Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China.

    Science.gov (United States)

    Xu, Xinpeng; Liu, Xiaoyan; He, Ping; Johnston, Adrian M; Zhao, Shicheng; Qiu, Shaojun; Zhou, Wei

    2015-01-01

    Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L.) were collected in four maize agro-ecological regions of China, and the optimal management (OPT), farmers' practice (FP), a series of nutrient omission treatments were used to analyze yield gap, nutrient use efficiency and indigenous nutrient supply by adopting meta-analysis and ANOVA analysis. Across all sites, the average yield gap between OPT and FP was 0.7 t ha-1, the yield response to nitrogen (N), phosphorus (P), and potassium (K) were 1.8, 1.0, and 1.2 t ha-1, respectively. The soil indigenous nutrient supply of N, P, and K averaged 139.9, 33.7, and 127.5 kg ha-1, respectively. As compared to FP, the average recovery efficiency (RE) of N, P, and K with OPT increased by percentage point of 12.2, 5.5, and 6.5, respectively. This study indicated that there would be considerable potential to further improve yield and nutrient use efficiency in China, and will help develop and inform agricultural policies and strategies, while some management measures such as soil, plant and nutrient are necessary and integrate with advanced knowledge and technologies.

  19. A natural variant of NAL1, selected in high-yield rice breeding programs, pleiotropically increases photosynthesis rate

    Science.gov (United States)

    Takai, Toshiyuki; Adachi, Shunsuke; Taguchi-Shiobara, Fumio; Sanoh-Arai, Yumiko; Iwasawa, Norio; Yoshinaga, Satoshi; Hirose, Sakiko; Taniguchi, Yojiro; Yamanouchi, Utako; Wu, Jianzhong; Matsumoto, Takashi; Sugimoto, Kazuhiko; Kondo, Katsuhiko; Ikka, Takashi; Ando, Tsuyu; Kono, Izumi; Ito, Sachie; Shomura, Ayahiko; Ookawa, Taiichiro; Hirasawa, Tadashi; Yano, Masahiro; Kondo, Motohiko; Yamamoto, Toshio

    2013-01-01

    Improvement of leaf photosynthesis is an important strategy for greater crop productivity. Here we show that the quantitative trait locus GPS (GREEN FOR PHOTOSYNTHESIS) in rice (Oryza sativa L.) controls photosynthesis rate by regulating carboxylation efficiency. Map-based cloning revealed that GPS is identical to NAL1 (NARROW LEAF1), a gene previously reported to control lateral leaf growth. The high-photosynthesis allele of GPS was found to be a partial loss-of-function allele of NAL1. This allele increased mesophyll cell number between vascular bundles, which led to thickened leaves, and it pleiotropically enhanced photosynthesis rate without the detrimental side effects observed in previously identified nal1 mutants, such as dwarf plant stature. Furthermore, pedigree analysis suggested that rice breeders have repeatedly selected the high-photosynthesis allele in high-yield breeding programs. The identification and utilization of NAL1 (GPS) can enhance future high-yield breeding and provides a new strategy for increasing rice productivity. PMID:23985993

  20. Lotus-leaf-like structured chitosan–polyvinyl pyrrolidone films as an anti-adhesion barrier

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jin Ik; Kang, Min Ji; Lee, Woo-Kul, E-mail: leewo@dankook.ac.kr

    2014-11-30

    Highlights: • Improved mechanical properties by hydrogen bond between chitosan and PVP chains. • Improved anti-adhesion effect by lotus-leaf-like structured chitosan–PVP (L-chitosan–PVP) film. • L-Chitosan–PVP film as a blood/tissue anti-adhesion barrier for post-surgical treatment. - Abstract: For postsurgical anti-adhesion barrier applications, lotus-leaf-like structured chitosan–PVP films were prepared using a solution casting method with dodecyltrichloro-immobilized SiO{sub 2} nanoparticles. We evaluated whether the lotus-leaf-like structured chitosan–PVP films (L-chitosan–PVP) could be applied as postsurgical anti-adhesion barriers. A recovery test using a tensile strength testing machine and measurement of crystallinity using X-ray diffraction indicated that films with 75% PVP were the optimal composition of the chitosan–PVP films. Also, dodecyltrichloro-immobilized SiO{sub 2} nanoparticles were synthesized and sprayed on the film after pretreatment with the instant bio-glue. Analysis of cell adhesion, proliferation, and anti-thrombus efficiency were performed via a WST assay, field emission scanning electron microscopy, and hemacytometry. The contact angle with the lotus-leaf-like surface was of approximately 150°. Furthermore, the L-chitosan–PVP film yielded a lower cell and platelet adhesion rate (around less than 4%) than that yielded by the untreated film. These results indicate that the lotus-leaf-like structure has a unique property and that this novel L-chitosan–PVP film can be applied as a blood/tissue-compatible, biodegradable material for implantable medical devices that need an anti-adhesion barrier.

  1. Lotus-leaf-like structured chitosan–polyvinyl pyrrolidone films as an anti-adhesion barrier

    International Nuclear Information System (INIS)

    Lim, Jin Ik; Kang, Min Ji; Lee, Woo-Kul

    2014-01-01

    Highlights: • Improved mechanical properties by hydrogen bond between chitosan and PVP chains. • Improved anti-adhesion effect by lotus-leaf-like structured chitosan–PVP (L-chitosan–PVP) film. • L-Chitosan–PVP film as a blood/tissue anti-adhesion barrier for post-surgical treatment. - Abstract: For postsurgical anti-adhesion barrier applications, lotus-leaf-like structured chitosan–PVP films were prepared using a solution casting method with dodecyltrichloro-immobilized SiO 2 nanoparticles. We evaluated whether the lotus-leaf-like structured chitosan–PVP films (L-chitosan–PVP) could be applied as postsurgical anti-adhesion barriers. A recovery test using a tensile strength testing machine and measurement of crystallinity using X-ray diffraction indicated that films with 75% PVP were the optimal composition of the chitosan–PVP films. Also, dodecyltrichloro-immobilized SiO 2 nanoparticles were synthesized and sprayed on the film after pretreatment with the instant bio-glue. Analysis of cell adhesion, proliferation, and anti-thrombus efficiency were performed via a WST assay, field emission scanning electron microscopy, and hemacytometry. The contact angle with the lotus-leaf-like surface was of approximately 150°. Furthermore, the L-chitosan–PVP film yielded a lower cell and platelet adhesion rate (around less than 4%) than that yielded by the untreated film. These results indicate that the lotus-leaf-like structure has a unique property and that this novel L-chitosan–PVP film can be applied as a blood/tissue-compatible, biodegradable material for implantable medical devices that need an anti-adhesion barrier

  2. The effect of foliar feeding of potassium salts and urea in spinach on gas exchange, leaf yield and quality

    Directory of Open Access Journals (Sweden)

    Edward Borowski

    2012-12-01

    Full Text Available In a pot experiment conducted in a phytotron, the effectiveness of foliar feeding of different potassium salts, with and without the addition of 0.5% CO(NH22, in spinach (Spinacia oleracea L. was investigated. Potassium was applied 3 times in the form of 1% solutions KCl, KNO3, K2SO4 and C6H5K3O7•H2O, compared to water as the control treatment. The obtained results show that foliar feeding of potassium salts in spinach is an efficient method of supplementing the level of K+ in plants during vegetation. Plants fed with KNO3 had the highest content of potassium in leaves, and those fertilized with K2SO4, C6H5K3O7 × H2O and KCl had an only slightly lower potassium content. The application of potassium salts resulted in more intensive gas exchange in leaves (stomatal conductance, photosynthesis, transpiration and, as a consequence of that, increased leaf yield. Potassium nitrate and citrate influenced most effectively the abovementioned processes. The treatment of spinach with potassium salts resulted in an increased content of protein, chlorophyll, carotenoids, nitrates and iron as well as a decreased content of vitamin C and calcium in leaves.

  3. Effects of planting method on agronomic characteristics, yield and yield components of sweet and super sweet corn (Zea mays L. varieties under saline conditions

    Directory of Open Access Journals (Sweden)

    F. Faridi

    2016-05-01

    Full Text Available In order to evaluate the effects of planting pattern on morphological, Phonological, yield and yield components of sweet and super sweet corn (Zea mays L. varieties under saline conditions, a field experiment was conducted as split plots based on a randomized complete block design with four replications. Planting pattern in 3 levels included one row in ridge, two row in ridge and furrow planting, as a main plot and varieties in 4 levels sweet corn with 2 types (KSc 403 su, Merit and super sweet with two types (Basin, obsession as sub plots. The results showed that planting pattern had significant differences on plant height, ear height, leaf length, leaf width, number of kernel per row, number of rows per ear and 1000-kernel weight. but had no significant effects on the length of tassel, number of leaf/plant, number of leaf per plant above ear, stem diameter, time of anthesis, time of silking, anthesis silking interval ASI, grain yield, biological yield and harvest index. Different varieties had significant effects on the total characteristics studied except number of leaf above ear and stem diameter. Most of the conservable grain yield and harvest index was in Obsession variety (10 kg and 39%, respectively and the least was seen in Basin (4 kg and 20%, respectively. The result showed that use of furrow planting pattern for sweet and super sweet corn in saline conditions can effects result in higher yield.

  4. Leaf gas exchange and nutrient use efficiency help explain the distribution of two Neotropical mangroves under contrasting flooding and salinity

    Science.gov (United States)

    Cardona-Olarte, Pablo; Krauss, Ken W.; Twilley, Robert R.

    2013-01-01

    Rhizophora mangle and Laguncularia racemosa co-occur along many intertidal floodplains in the Neotropics. Their patterns of dominance shift along various gradients, coincident with salinity, soil fertility, and tidal flooding. We used leaf gas exchange metrics to investigate the strategies of these two species in mixed culture to simulate competition under different salinity concentrations and hydroperiods. Semidiurnal tidal and permanent flooding hydroperiods at two constant salinity regimes (10 g L−1 and 40 g L−1) were simulated over 10 months. Assimilation (A), stomatal conductance (gw), intercellular CO2 concentration (Ci), instantaneous photosynthetic water use efficiency (PWUE), and photosynthetic nitrogen use efficiency (PNUE) were determined at the leaf level for both species over two time periods. Rhizophora mangle had significantly higher PWUE than did L. racemosa seedlings at low salinities; however, L. racemosa had higher PNUE and stomatal conductance and gw, accordingly, had greater intercellular CO2 (calculated) during measurements. Both species maintained similar capacities for assimilation at 10 and 40 g L−1 salinity and during both permanent and tidal hydroperiod treatments. Hydroperiod alone had no detectable effect on leaf gas exchange. However, PWUE increased and PNUE decreased for both species at 40 g L−1 salinity compared to 10 g L−1. At 40 g L−1 salinity, PNUE was higher for L. racemosa than R. mangle with tidal flooding. These treatments indicated that salinity influences gas exchange efficiency, might affect how gases are apportioned intercellularly, and accentuates different strategies for distributing leaf nitrogen to photosynthesis for these two species while growing competitively.

  5. Leaf Gas Exchange and Nutrient Use Efficiency Help Explain the Distribution of Two Neotropical Mangroves under Contrasting Flooding and Salinity

    Directory of Open Access Journals (Sweden)

    Pablo Cardona-Olarte

    2013-01-01

    Full Text Available Rhizophora mangle and Laguncularia racemosa cooccur along many intertidal floodplains in the Neotropics. Their patterns of dominance shift along various gradients, coincident with salinity, soil fertility, and tidal flooding. We used leaf gas exchange metrics to investigate the strategies of these two species in mixed culture to simulate competition under different salinity concentrations and hydroperiods. Semidiurnal tidal and permanent flooding hydroperiods at two constant salinity regimes (10 g L−1 and 40 g L−1 were simulated over 10 months. Assimilation (A, stomatal conductance (gw, intercellular CO2 concentration (Ci, instantaneous photosynthetic water use efficiency (PWUE, and photosynthetic nitrogen use efficiency (PNUE were determined at the leaf level for both species over two time periods. Rhizophora mangle had significantly higher PWUE than did L. racemosa seedlings at low salinities; however, L. racemosa had higher PNUE and gw and, accordingly, had greater intercellular CO2 (calculated during measurements. Both species maintained similar capacities for A at 10 and 40 g L−1 salinity and during both permanent and tidal hydroperiod treatments. Hydroperiod alone had no detectable effect on leaf gas exchange. However, PWUE increased and PNUE decreased for both species at 40 g L−1 salinity compared to 10 g L−1. At 40 g L−1 salinity, PNUE was higher for L. racemosa than R. mangle with tidal flooding. These treatments indicated that salinity influences gas exchange efficiency, might affect how gases are apportioned intercellularly, and accentuates different strategies for distributing leaf nitrogen to photosynthesis for these two species while growing competitively.

  6. Post-anthesis nitrate uptake is critical to yield and grain protein content in Sorghum bicolor.

    Science.gov (United States)

    Worland, Belinda; Robinson, Nicole; Jordan, David; Schmidt, Susanne; Godwin, Ian

    2017-09-01

    Crops only use ∼50% of applied nitrogen (N) fertilizer creating N losses and pollution. Plants need to efficiently uptake and utilize N to meet growing global food demands. Here we investigate how the supply and timing of nitrate affects N status and yield in Sorghum bicolor (sorghum). Sorghum was grown in pots with either 10mM (High) or 1mM (Low) nitrate supply. Shortly before anthesis the nitrate supply was either maintained, increased 10-fold or eliminated. Leaf sheaths of sorghum grown with High nitrate accumulated nitrate in concentrations >3-times higher than leaves. Removal of nitrate supply pre-anthesis resulted in the rapid reduction of stored nitrate in all organs. Plants receiving a 10-fold increase in nitrate supply pre-anthesis achieved similar grain yield and protein content and 29% larger grains than those maintained on High nitrate, despite receiving 24% less nitrate over the whole growth period. In sorghum, plant available N is important throughout development, particularly anthesis and grain filling, for grain yield and grain protein content. Nitrate accumulation in leaf sheaths presents opportunities for the genetic analysis of mechanisms behind nitrate storage and remobilization in sorghum to improve N use efficiency. Copyright © 2017 Elsevier GmbH. All rights reserved.

  7. Radiation-use efficiency of sunflower crops: effects of specific leaf nitrogen and ontogeny

    International Nuclear Information System (INIS)

    Hall, A.J.; Connor, D.J.; Sadras, V.O.

    1995-01-01

    Loss of nitrogen from the leaves and a reduction in specific leaf nitrogen (SLN, g N m −2 ) is associated with grain filling in sunflower (Helianthus annuus L.). To explore the relationship between crop radiation-use efficiency (RUE, g MJ −1 ) and SLN, crop biomass accumulation and radiation interception were measured between the bud-visible and physiological-maturity stages in crops growing under combinations of two levels of applied nitrogen (0 and 5 g N m −2 ) and two population densities (2.4 and 4.8 plants m −2 ). Both nitrogen fertilization and density had significant (P = 0.05) effects on crop biomass yield, nitrogen uptake, leaf area index and SLN, but the nitrogen effects were more pronounced for these and other crop variables. Linear regressions of accumulated biomass (OCdwt, corrected for the energy costs of oil synthesis in the grain) on accumulated intercepted short-wave radiation between bud visible and early grain filling provided appropriate and significantly (P = 0.05) different estimates of RUE for the pooled 0 g N m −2 (1.01 g OCdwt MJ −1 ) and 5 g N m −2 (1.18 g OCdwt MJ −1 ) treatments. When calculated for each inter-harvest interval, crop RUE varied in a curvilinear fashion during the season, with a broad optimum from 40 to 70 days after emergence of the crops, and with lower values earlier and later in the season. The reduction in RUE toward physiological maturity was particularly marked. A plot of RUE against SLN revealed a reduction in RUE at small SLN values, but the relationship may be confounded by ontogenetic changes in other factors. A published model (Sinclair and Horie (1989), Crop Sci., 29: 90–98) was used to explore the RUE/SLN relationship. The model was unable to reproduce the decline in RUE during the second half of the grain-filling period. It is suggested that an important cause of this failure may be the partition, in the model, of a fixed, rather than a variable, fraction of crop gross photosynthesis to

  8. Plant growth analysis used as secondary traits in selection for high yield on groundnut

    International Nuclear Information System (INIS)

    Manshuri, A.G.; Nugrahaeni

    1996-01-01

    Groundnut growth and yield can be expressed as the product to solar radiation interception (Qi), conversion efficiency of radiation to total dry matter (Ek) and partitioning efficiency to economic yield (Ep) or harvest index. Groundnut genotypes differ in characters related to Qi, Ek and Ep, and the characters have the possibility to be used as secondary traits in selection for high yield. Extinction coefficient (k) and leaf area index (LAI) are the influential factors in increasing Qi. Variability in leaf size lead to the description of the existence of variability in k value within the genotypes under study. LAI three is the level necessary to attain 90 percent total radiation absorption in groundnut. An increased of LAI exceeding four would be inefficient for increasing the fraction of radiation absorption. Convertion efficiency of radiation to total dry matter (Ek) related to the rate of plant photosynthesis and respiration, inspite of the need study the field, however, the study was still limited. Harvest index can be used as a secondary trait to identify high yield genotypes. There was a positive correlation between pod yield and harvest index. An increased of harvest index by 1 percent caused an increased of dry pod as high as 0.365 g/plant. ICG 1697, ICGV 86844 and ICGV 87161 gave yield more than 3.5 t/ha, and their total dry matter (TDM) were 49.2, 52.5 and 40.7 g/plant, whereas their harvest indexes (HI) were 0.47, 0.46 and 0.55, respectively. Theoretically, improvement of the groundnut pod yield can be attained by using variety which has TDM 52.5 g/plant and HI 0.55. Using HI as secondary selection criteria, five genotypes were selected, i.e., G/C/LM-88-B-25 (HI 0.59), local Irian and local Lombok (HI 0.57), ICGV 87161 and LM/ICGV 87165-B-2-1 (HI 0.55). Two genotypes were selected for their high TDM, namely ICGV 86844 and LM/ICGV 87165-88-B-82 [in

  9. Yield and water use efficiency of irrigated soybean in Vojvodina, Serbia

    Directory of Open Access Journals (Sweden)

    Pejić Borivoj

    2012-01-01

    Full Text Available Research was carried out at Rimski Šančevi experiment field of Institute of Field and Vegetable Crops in Novi Sad in the period 1993-2004. The experiment included an irrigated and non-irrigated control treatment. Irrigation water use efficiency (Iwue and evapotranspiration water use efficiency (ETwue were determined in order to assess the effectiveness of irrigation on soybean yield. The average yield increases of soybean due to irrigation practice was 0.82 t ha-1, ranging from 2.465 t ha-1 in years with limited precipitation and higher than average seasonal temperatures (2000 to 0 t ha-1 in rainy years (1996, 1997, 1999. Evapotranspiration water use efficiency (ETwue of soybean ranged from 0.11 kg m-3 to 1.36 kg m-3 with an average value of 0.66 kg m-3, while irrigation water use efficiency (Iwue varied from 0.11 kg m-3 to 1.04 kg m-3 with an average value of 0.56 kg m-3. Effect of irrigation on yield of soybean and results of both ETwue and Iwue which were similar to those obtained from the literature indicate that irrigation schedule of soybean in the study period was properly adapted to plant water requirements and water-physical soil properties. Determined values of ETwue and Iwue could be used for the planning, design and operation of irrigation systems, as well as for improving the production technology of soybean in the region.

  10. Leaf movement, photosynthesis and resource use efficiency responses to multiple environmental stress in Glycine max (soybean)

    International Nuclear Information System (INIS)

    Rosa, L.M.G.

    1993-01-01

    Increases in the concentration of greenhouse gases in the atmosphere, may cause a significant increase in temperature, with implications for general wind patterns and precipitation. Reductions in stratospheric ozone will result in increased levels of UV-B reaching earth's surface. During their lifetime plants must deal with a variety of co-occurring environmental stresses. Accordingly, studies into plant responses to multiple environmental factors is important to our understanding of limits to their growth, productivity, and distribution. Heliotropic leaf movements are a generalized plant response to environmental stresses, and the pattern of these movements can be altered by resource availability (e.g., water, and nitrogen). Previous greenhouse and field studies have demonstrated damaging effects of UV-B radiation in crop species, including soybean. Documented in this paper are Leaf movement and gas exchange responses of four soybean cultivars with different sensitivity to UV-B radiation to enhanced levels of UV-B, and modifications of these responses caused by water stress and nitrogen fertilization. UV-B radiation had no effect on the patterns of leaf orientation in soybean; however, a ranking of the cultivars based on midday leaf angles was the same as the ranking of these cultivars based on their sensitivity to UV-B radiation. Water and nitrogen altered the leaf movement patterns of soybeans. Gas exchange parameters in all four cultivars responded in a similar fashion to changes in leaf water potential. Reductions in water availability resulted in lower discrimination. Nitrogen fertilization in cv Forrest, also resulted in lower discrimination, especially under low water regimes, indicating a higher water use efficiency for fertilized plants. UV-B radiation resulted in lower discrimination in the UV-B sensitive CNS cultivar, indicating a stronger stomatal limitation to photosynthesis under increased UV-B levels

  11. Evaluation of Some Morphological Characteristics, Water Use Efficiency and Essential Oil of Basil (Ocimum basilicum var. keshkeni luvelou under Application of Malva Leaves and Superabsorbent Polymer

    Directory of Open Access Journals (Sweden)

    S. Beigi

    2016-02-01

    Full Text Available Introduction: Medicinal plants are rich in active substances and primarily have been used in the manufacture of many drugs. Basil (Ocimum basilicum L. is one of the important medicinal plants whichbelongs to the Lamiaceae family. Basil essential oil content (between 0.5 to 1.5 percent varies according to climatic conditions of habitat location. Basilneeds a lot of water during growth period and it is very sensitive to water stress and shows wilting symptoms very soon after water shortage. Iran is located in an arid and semi-arid region which has little precipitation that is not enough for crop water requirements. Nowadays, the use of superabsorbent polymers is one of the ways to create sustainable agriculture and increase irrigation efficiency. They can store high water or aqueous solutions in root zone of plants and to reduce negative effects of drought stress. So, improvement of plant growth, increasing of irrigation intervals, reducing water loss and costs of irrigation is due to the application of superabsorbent polymers. Mucilages are also the herbal polysaccharides, soluble in water, and commonly include carbohydrates and can be used as hydrophilic polymers. The aims of this investigation were to study the effects of hydrophilic polymers on water use efficiency, morphological characteristics (dry matter, leaf area, and leaf number, essential oil quantity and yield of basil to harden plant to drought stress and to evaluate its potential to cultivate in arid regions. In addition, taking steps forward towards sustainable agriculture, by reducing the cost of agricultural production, helps protecting the environment. Materials and Methods: This research was conducted as a pot experiment at the department of Horticultural Science‚ college of Agricultural‚ Ferdowsi University of Mashhad‚ Iran, during 2012-2013.The research was set out in a factorial experiment on the basis of completely randomized block design with three replications

  12. Natural Pineapple Leaf Fibre Extraction On Josapine And Morris

    Directory of Open Access Journals (Sweden)

    Mazalan Muhammad Firdaus

    2017-01-01

    Full Text Available The pineapple’s leaf plant contains approximately 2.5% to 3.5% of strong white silky fibres. These fibres are useful and can be extracted from the leaves. There are a few ways to extract the fibre such as hand scrapping and by extraction machine. The objective of this research is to study the quality of fibre extraction by using different age of pineapple leaf. Next, the study aims to compare the quality of Josapine and Morris pineapple leaf with tensile test. Fibre yield percentage are calculated to determine which type of pineapple leaf produce high production of dry fibre. The mechanical properties of the fibres are analysed by Tensile Test under American Standard Testing Methods (ASTM C1577-03 and Scanning Electron Microscope (SEM. The result of the fibre yield percentage show the Josapine type on 12 month ages are the highest value fibre yield percentage which is 7.89%. Based on fibre yield percentages, it showed the Josapine type produce better dry fibre production compare to Morris type. Based on mechanical test, it showed Josapine type on 12 months ages are the strongest fibre compare to Morris type since it can withstand on 67.6 N of load.

  13. Modeling stomatal conductance in the earth system: linking leaf water-use efficiency and water transport along the soil-plant-atmosphere continuum

    Science.gov (United States)

    Bonan, G. B.; Williams, M.; Fisher, R. A.; Oleson, K. W.

    2014-09-01

    The Ball-Berry stomatal conductance model is commonly used in earth system models to simulate biotic regulation of evapotranspiration. However, the dependence of stomatal conductance (gs) on vapor pressure deficit (Ds) and soil moisture must be empirically parameterized. We evaluated the Ball-Berry model used in the Community Land Model version 4.5 (CLM4.5) and an alternative stomatal conductance model that links leaf gas exchange, plant hydraulic constraints, and the soil-plant-atmosphere continuum (SPA). The SPA model simulates stomatal conductance numerically by (1) optimizing photosynthetic carbon gain per unit water loss while (2) constraining stomatal opening to prevent leaf water potential from dropping below a critical minimum. We evaluated two optimization algorithms: intrinsic water-use efficiency (ΔAn /Δgs, the marginal carbon gain of stomatal opening) and water-use efficiency (ΔAn /ΔEl, the marginal carbon gain of transpiration water loss). We implemented the stomatal models in a multi-layer plant canopy model to resolve profiles of gas exchange, leaf water potential, and plant hydraulics within the canopy, and evaluated the simulations using leaf analyses, eddy covariance fluxes at six forest sites, and parameter sensitivity analyses. The primary differences among stomatal models relate to soil moisture stress and vapor pressure deficit responses. Without soil moisture stress, the performance of the SPA stomatal model was comparable to or slightly better than the CLM Ball-Berry model in flux tower simulations, but was significantly better than the CLM Ball-Berry model when there was soil moisture stress. Functional dependence of gs on soil moisture emerged from water flow along the soil-to-leaf pathway rather than being imposed a priori, as in the CLM Ball-Berry model. Similar functional dependence of gs on Ds emerged from the ΔAn/ΔEl optimization, but not the ΔAn /gs optimization. Two parameters (stomatal efficiency and root hydraulic

  14. Effects of Sowing Date, Planting Pattern and Nitrogen Levels on Leaf and Flower Essential Oil, Yield and Component Yield Grain of Buckwheat (Fagopyroum esculentum Moench

    Directory of Open Access Journals (Sweden)

    M. R Sobhani

    2017-12-01

    Full Text Available Introduction Buckwheat which has been scientifically named Fagopyrum esculentum can be considered as a yearling broad-leaved plant belonging to the family of Polygonaceae which is known as false Cereal. Its seeds are in use as a nutritional and medicinal product that is due to the rutin content of them. As the population is rapidly increasing worldwide, a solution must be found to supply necessary food. What agriculture science is responsible for is to produce more products with better quality in order to meet this increasing population’s needs so that food poverty and starvation are more likely to be removed and keep food safety. Considering the fact that buckwheat is of a variety of medical, industrial and food applications and in our country and some other ones, it has not been seriously cultivated, this plant must be used as a new plant and it should be extensively applied in multiple planting systems (summer planting for commercial goals through producing seeds while its nutritional value is more than grain and it can be regarded as a rich source of high quality protein, amino acid necessary for lysine, high starch percent, minerals and vitamins for different applications involving cake flour, frumenty and soup and improving the optimal rate of rutin as a secondary metabolite having effective medical features concerning our country’s climatic conditions. Materials and Methods In order to investigate the effects of sowing date, planting patterns and nitrogen on leaf and flower rutin, yield and yield component of Buckwheat plant, a field study was conducted during 2010 and 2011 in Agricultural Research Institute of Arak, Iran. The experimental design was regarded as the randomized complete block design in the form of split plot factorial with three replications. Planting treatments as the fundamental elements may be implemented at two levels including the mounds with the width of 50 cm associated with two planting rows regarding the

  15. Effect of polyethylene coated calcium carbide on physiology, photosynthesis, growth and yield of sweet pepper

    International Nuclear Information System (INIS)

    Ahmed, W.; Yaseen, M.; Arshad, M.; Shahid, M.

    2014-01-01

    Polyethylene coated calcium carbide (PCC) is a potent and continuous slowly releasing source of acetylene and ethylene. It potentially improves plant growth by affecting physiology of plant. A pot study was conducted to investigate comparative effects of different rates of PCC on growth and yield attributes of sweet pepper. PCC performed better when applied with soil applied fertilizers. Results revealed that hormonal properties of calcium carbide significantly influenced physiological nutrient use efficiency and vegetative growth by affecting photosynthetic and physiological parameters of sweet pepper. Application of 20 mg PCC kg/sup -1/ soil with soil applied recommended dose of NPK fertilizers significantly improved the net photosynthetic rate by 32%, stomatal conductance by 11%, transpiration rate by 14%, carboxylation efficiency by 47%, physiological water use efficiency by 13%, physiological nitrogen use efficiency by 29% over the control treatment. This improvement in physiological attributes resulted in increase in leaf area by 20%, leaf area index by 78%, total plant dry weight by 35%, flower and fruits by 29% and fruit yield by 24% compared to the treatment of alone recommended dose of NPK fertilizers. Present study suggests that application of PCC particularly at the rate of 20mg PCC kg/sup -1/ soil plus recommended dose of NPK fertilizers improved about 25% sweet pepper production compared to its production in the alone recommended fertilizer treatment. (author)

  16. Comparison of sodium carbonate pretreatment for enzymatic hydrolysis of wheat straw stem and leaf to produce fermentable sugars.

    Science.gov (United States)

    Jin, Yongcan; Huang, Ting; Geng, Wenhui; Yang, Linfeng

    2013-06-01

    The specific characteristics of biomass structure and chemical composition of straw stem and leaf may result in different behavior of pretreatment and enzymatic hydrolysis. In this work, sodium carbonate (SC) was employed as a pretreatment to improve the enzymatic digestibility of wheat straw. The chemical composition and enzymatic hydrolysis of wheat straw stem and leaf (sheath included) were investigated comparatively. Most of the polysaccharides are kept in the solid fractions after SC pretreatment, while the stem has better delignification selectivity than leaf at high temperature. The enzymatic hydrolysis efficiency of wheat straw leaf is significantly higher than that of stem. The maximum total sugar yield from SC pretreated leaf was about 16% higher than stem. The results show that sodium carbonate is of great potential to be used as a pretreatment for the production of bioethanol from straw handling waste in a straw pulp mill with a low feedstock cost. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Comparison of Regenerative Braking Efficiencies of MY2012 and MY2013 Nissan Leaf

    Directory of Open Access Journals (Sweden)

    Albert Boretti

    2016-07-01

    Full Text Available The use of kinetic energy recovery systems (KERS is the best solution presently available to dramatically improve the energy economy of passenger cars. The paper presents an experimental analysis of the energy flow to and from the battery of a MY 2012 and a MY 2013 Nissan Leaf covering the Urban Dynamometer Driving Schedule (UDDS. The two vehicles differ for the integration of the electric drivetrain component, plus a different use of the electric motor and the regenerative brakes, in addition to a different weight. It is shown that while the efficiency propulsive power to vehicle / power from battery are basically unchanged, at about 87-89 %, the efficiency power to the battery / braking power to vehicle are significantly improved from values of about 70-80 % to values of 72-87 %. The analysis provides a state-of-the-art benchmark of the propulsion and regenerative braking efficiencies of electric vehicles.

  18. FORMATION OF PARSLEY YIELD AND THE DEGREE OF ITS RESPONSIVENESS TO FOLIAR

    Directory of Open Access Journals (Sweden)

    E. G. Gadzhimustapaeva

    2017-01-01

    Full Text Available Now the actual task of organic plant cultivation is to provide the population with ecologically clean and health-care products in volumes sufficient for everyone. Recently, growth and development plant regulators are used more often to guarantee the high yield as well as a quality and marketable view of final products in zonal system of protection of leafy vegetables. The range of their efficiency can significantly vary depending on zone of cultivation. The research study on collection of leafy parsley accessions of different origin distinguished by resistance to freeze was given in the article. The morphobiological characteristics of studied accessions are given, where highly productive and yielding accession ‘k.vr494’ was selected out. The influence of chelated microelements, growth regulators and fertilizers on foliage and seed productivity has been shown in south Dagestan. The comparative trial test showed the high efficiency of liquid concentrate of organic boron, organoboron and silicon-containing micronutrient ‘Siliplant’. The total foliage productivity after three cutting was 28.8 kg. with application of concentrate of organoboron and 16.53 kg. in control. 24.74 kg. and 14.34 kg. respectively were obtained with application of Siliplant. This result showed that high yield of foliage was produced after first cutting. Out of all experimental variants the best leaf regrowth was noticed with application of Mikrovita. Leaf regrowth at intermediate cutting showed that there was a growth-stimulating action of Mikrovita and Siliplant.

  19. Constraints to the potential efficiency of converting solar radiation into phytoenergy in annual crops: from leaf biochemistry to canopy physiology and crop ecology.

    Science.gov (United States)

    Yin, Xinyou; Struik, Paul C

    2015-11-01

    A new simple framework was proposed to quantify the efficiency of converting incoming solar radiation into phytoenergy in annual crops. It emphasizes the need to account for (i) efficiency gain when scaling up from the leaf level to the canopy level, and (ii) efficiency loss due to incomplete canopy closure during early and late phases of the crop cycle. Equations are given to estimate losses due to the constraints in various biochemical or physiological steps. For a given amount of daily radiation, a longer daytime was shown to increase energy use efficiency, because of the convex shape of the photosynthetic light response. Due to the higher cyclic electron transport, C4 leaves were found to have a lower energy loss via non-photochemical quenching, compared with C3 leaves. This contributes to the more linear light response in C4 than in C3 photosynthesis. Because of this difference in the curvature of the light response, canopy-to-leaf photosynthesis ratio, benefit from the optimum acclimation of the leaf nitrogen profile in the canopy, and productivity gain from future improvements in leaf photosynthetic parameters and canopy architecture were all shown to be higher in C3 than in C4 species. The indicative efficiency of converting incoming solar radiation into phytoenergy is ~2.2 and 3.0% in present C3 and C4 crops, respectively, when grown under well-managed conditions. An achievable efficiency via future genetic improvement was estimated to be as high as 3.6 and 4.1% for C3 and C4 crops, respectively. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Exclusion of solar UV radiation improves photosynthetic performance and yield of wheat varieties.

    Science.gov (United States)

    Kataria, Sunita; Guruprasad, K N

    2015-12-01

    Field studies were conducted to determine the potential for alterations in photosynthetic performance and grain yield of four wheat (Triticum aestivum) varieties of India- Vidisha, Purna, Swarna and Naveen Chandausi by ambient ultraviolet radiation (UV). The plants were grown in specially designed UV exclusion chambers, wrapped with filters that excluded UV-B (solar UV exclusion increased the leaf mass per area ratio, leaf weight ratio and chlorophylls per unit area of flag leaves in all the four varieties of wheat. Polyphasic chlorophyll a fluorescence transients from the flag leaves of UV excluded wheat plants gave a higher fluorescence yield. Exclusion of solar UV significantly enhanced photosynthetic performance as a consequence of increased efficiency of PS II, performance index (PIABS) and rate of photosynthesis in the flag leaves of wheat varieties along with a remarkable increase in carbonic anhydrase, Rubisco and nitrate reductase activities. This additional fixation of carbon and nitrogen by exclusion of UV was channelized towards the improvement in grain yield of wheat varieties as there was a decrease in the UV-B absorbing substances and an increase in soluble protein content in flag leaves of all the four varieties of wheat. The magnitude of response for UV exclusion for all the measured parameters was higher in two varieties of wheat Vidisha and Purna as compared to Swarna and Naveen Chandausi. Cumulative stress response index (CSRI) for each variety was developed from the cumulative sum of physiological and yield parameters such as leaf mass area ratio of flag leaf, total chlorophyll content, performance index at absorption basis, rate of photosynthesis and grain yield. All the varieties had a negative CSRI, demonstrating a negative impact of ambient UV radiation. Naveen Chandausi and Swarna are less sensitive to ambient UV radiation; Vidisha is more sensitive to both UV-A and UV-B and Purna is more sensitive to ambient UV-B radiation. Copyright

  1. Refining the application of direct embryogenesis in sugarcane: Effect of the developmental phase of leaf disc explants and the timing of DNA transfer on transformation efficiency.

    Science.gov (United States)

    Snyman, S J; Meyer, G M; Richards, J M; Haricharan, N; Ramgareeb, S; Huckett, B I

    2006-10-01

    A rapid in vitro protocol using direct somatic embryogenesis and microprojectile bombardment was investigated to establish the developmental phases most suitable for efficient sugarcane transformation. Immature leaf roll disc explants with and without pre-emergent inflorescence tissue were compared. It was shown that for effective transformation to occur, explants should be cultured for several days to allow initiation of embryo development prior to bombardment. Leaf roll discs with pre-emergent inflorescences showed a higher degree of embryogenic competence than non-flowering explants, and transformation efficiency was higher when explants containing floral initials were bombarded. Despite the occurrence of high numbers of phenotypically negative plants, combining the use of inflorescent leaf roll discs with direct embryogenic regeneration has the potential to improve the speed and efficiency of transgenesis in sugarcane.

  2. YIELD AND ITS COMPONENTS IN FIELD PEA (Pisum arvense L. LINES

    Directory of Open Access Journals (Sweden)

    A TEKELI

    2004-04-01

    Full Text Available Morphological characters such as main stem length (cm, number of branches per plant, leaf length (cm, number of leaves per main stem, number of leaflets per leaf, diameter of main stem (mm, pods / main stem and seeds / pod as well as agricultural herbage yield (t ha-1, dry matter yield (t ha-1, seed yield (t ha-1, crude protein (% were investigated in Trakya, during the 1999-2002. The maximum main stem length (124.375 cm, leaf length (24.808 cm, number of pods per main stem (16.526, herbage yield (27.881 t ha-1, dry matter yield (7.319 t ha-1 and seed yield (2.590 t ha-1 were determined from the 16-K and 16-DY field pea lines. K line has given higher values than four lines for the number of branches per plant (5.567. Main stem diameter ranged from 3.077 to 4.300 mm. It’s found that the 23.025 leaves/main stem, 6.833 leaflets/leaf, 7.692 seeds/pod and 17.550% crude protein from the field pea lines.

  3. Effect of nitrogen supply on leaf growth, leaf nitrogen economy and photosynthetic capacity in potato

    NARCIS (Netherlands)

    Vos, J.; Putten, van der P.E.L.

    1998-01-01

    Literature reports show little effect of nitrogen supply on radiation use efficiency in potato and in other dicotyledonous C3 species. This paper tests the hypothesis that potato reduces leaf size rather than leaf nitrogen concentration and photosynthetic capacity when nitrogen is in short supply.

  4. Water- and nitrogen-dependent alterations in the inheritance mode of transpiration efficiency in winter wheat at the leaf and whole-plant level.

    Science.gov (United States)

    Ratajczak, Dominika; Górny, Andrzej G

    2012-11-01

    The effects of contrasting water and nitrogen (N) supply on the observed inheritance mode of transpiration efficiency (TE) at the flag-leaf and whole-season levels were examined in winter wheat. Major components of the photosynthetic capacity of leaves and the season-integrated efficiency of water use in vegetative and grain mass formation were evaluated in parental lines of various origins and their diallel F(2)-hybrids grown in a factorial experiment under different moisture and N status of the soil. A broad genetic variation was mainly found for the season-long TE measures. The variation range in the leaf photosynthetic indices was usually narrow, but tended to slightly enhance under water and N shortage. Genotype-treatment interaction effects were significant for most characters. No consistency between the leaf- and season-long TE measures was observed. Preponderance of additivity-dependent variance was mainly identified for the season-integrated TE and leaf CO(2) assimilation rate. Soil treatments exhibited considerable influence on the phenotypic expression of gene action for the residual leaf measures. The contribution of non-additive gene effects and degree of dominance tended to increase in water- and N-limited plants, especially for the leaf transpiration rate and stomatal conductance. The results indicate that promise exists to improve the season-integrated TE. However, selection for TE components should be prolonged for later hybrid generations to eliminate the masking of non-additive causes. Such evaluation among families grown under sub-optimal water and nitrogen supply seems to be the most promising strategy in winter wheat.

  5. Effect of Mycorrhiza Symbiosis on Yield, Yield Components and Water Use Efficiency of Sesame (Sesamum indicum L. Affected by Different Irrigation Regimes in Mashhad Condition

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2016-02-01

    Full Text Available Introduction Plant association with mycorrhiza has been considered as one of the options to improve input efficiency particularly for water and nutrient - (Allen and Musik, 1993; Bolan, 1991. This has been due to kncreasing the absorbing area of the root and therefore better contact with water and nutrients. Inoculation with mycorrhiza enhances nutrient uptake with low immobility such as phosphorus and solphur-, improve association and could be an option to drought and other environmental abnormalities such as salinity (Rice et al., 2002. Moreover, higher water use efficiency (WUE for crops -has been reported in the literatures (Sekhara and Reddy, 1993.The sustainable use of scarce water resources in Iran is a priority for agricultural development. The pressure of using water in agriculture sector is increasing, so creating ways to improve water-use efficiency and taking a full advantage of available water are crucial. Water stress reduce crop yield by impairing the growth of crop canopy and biomass. Scheduling water application is very crucial for efficient use of drip irrigation system, as excessive irrigation reduces yield, while inadequate irrigation causes water stress and reduces production. The aim of present study was to evaluate the symbiotic effect of mycorrhiza on yield, yield components and water use efficiency of sesame under different irrigation regimes in Mashhad. Material and Methods In order to investigate the impact of inoculation with two species of Arbuscular mycorrhiza fungi on yield, yield components and water use efficiency (WUE of sesame (Sesamum indicum L. under different irrigation regimes, an experiment was conducted as split plot based on a randomized complete block design with three replications during two growing seasons 2009-2010 and 2010-2011 at the Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad.. The experimental factors were three irrigation regimes include 2000, 3000 and

  6. Efficiency and yield spectra of inorganic scintillates

    International Nuclear Information System (INIS)

    Rodnyi, P.A.

    1998-01-01

    Recent developments in the field of energy loss in inorganic scintillators are reviewed. The main parameters, which control the fundamental limit of the scintillator energy efficiency, are determined. It is shown that together with simple cascade processes one should take into account the production of plasmons to estimate the energy efficiency of scintillators or other phosphors excited by an ionizing radiation. Core-to-valence luminescence related to 5pCs→3pCl transitions is investigated in some chlorides: CsCl, KCl, RbCl, NaCl, KCaCl 3 , RbCaCl 3 . The yield spectra of the crystals in the VUV and X-ray regions are also studied. It is shown that the 4pRb-core states are involved in the process of creation of holes in the 5pCs-core band in Rb-based crystals. The formation of holes in the potassium core band acts as a competing process and suppresses the radiative core-to-valence transitions

  7. [PS II photochemical efficiency in flag leaf of wheat varieties and its adaptation to strong sun- light intensity on farmland of Xiangride in Qinghai Province, Northwest China].

    Science.gov (United States)

    Shi, Sheng-Bo; Chen, Wen-Jie; Shi, Rui; Li, Miao; Zhang, Huai-Gang; Sun, Ya-Nan

    2014-09-01

    Taking four wheat varieties developed by Northwest Institute of Plateau Biology, Chinese Academy of Sciences, as test materials, with the measurement of content of photosynthetic pigments, leaf area, fresh and dry mass of flag leaf, the PS II photochemistry efficiency of abaxial and adaxial surface of flag leaf and its adaptation to strong solar radiation during the period of heading stage in Xiangride region were investigated with the pulse-modulated in-vivo chlorophyll fluorescence technique. The results indicated that flag leaf angle mainly grew in horizontal state in Gaoyuan 314, Gaoyuan 363 and Gaoyuan 584, and mainly in vertical state in Gaoyuan 913 because of its smaller leaf area and larger width. Photosynthetic pigments were different among the 4 varieties, and positively correlated with intrinsic PS II photochemistry efficiencies (Fv/Fm). In clear days, especially at noon, the photosynthetic photoinhibition was more serious in abaxial surface of flag leaf due to directly facing the solar radiation, but it could recover after reduction of sunlight intensity in the afternoon, which meant that no inactive damage happened in PS II reaction centers. There were significant differences of PS II actual and maximum photochemical efficiencies at the actinic light intensity (ΦPS II and Fv'/Fm') between abaxial and adaxial surface, and their relative variation trends were on the contrary. The photochemical and non-photochemical quenching coefficients (qP and NPQ) had a similar tendency in both abaxial and adaxial surfaces. Although ΦPS II and qP were lower in adaxial surface of flag leaf, the Fv'/Fm' was significantly higher, which indicated that the potential PS II capture efficiency of excited energy was higher. The results demonstrated that process of photochemical and non-photochemical quenching could effectively dissipate excited energy caused by strong solar radiation, and there were higher adaptation capacities in wheat varieties natively cultivated in

  8. Evaluation Yield of Sunflower (Farrokh cultivar under Effects of Conventional Deficit Irrigation and Partial Root Zone Drying

    Directory of Open Access Journals (Sweden)

    A. Rezaei Estakhroeih

    2015-06-01

    Full Text Available Water shortage is the most important factors on crop production in the world. Several methods of deficit irrigation are solutions for reduction of irrigation water. To understand the effects of conventional deficit irrigation and partial root zone drying treatments on yield, yield components and water use efficiency of sunflower (Farrokh cultivar, one study was carried out. The research was conducted on Shahid Bahonar University of Kerman in the spring of 2011. A factorial experiment in a randomized complete block design with one control (full irrigation and 18 deficit irrigation treatments in three replications was considered. Deficit irrigation treatments were: conventional deficit irrigation (irrigation with %80, %60 and %40 ETP and partial root zone drying (irrigation with %80, %60 and %40 ETP. Every deficit irrigation treatment was conducted in three growth stage of sunflower (all periods of growth, vegetative growth stage and reproductive growth stage.The results showed that the conventional deficit irrigation treatments (irrigation with 80% ETP in vegetative growth had the highest plant height, leaf area, leaf area index and head diameter. Also, the maximum biological yield equal to49054, maximum grain yield is equal to 9934/3 and maximum oil yield is equal to 2441/2 kg per hectare in the conventional deficit irrigation treatments (irrigation with 80% ETP in vegetative growth occurred.The highest water use efficiency for grain yield is equal to 1/46,forbiological yield equal to7/21 and for dry forage yield is equal 5/7 kilograms per cubic meter of water. According to results,conventional deficit irrigation (irrigation with %80, %60 and %40 ETP is recommended on based.

  9. Constraints to the potential efficiency of converting solar radiation into phytoenergy in annual crops: from leaf biochemistry to canopy physiology and crop ecology

    NARCIS (Netherlands)

    Yin, X.; Struik, P.C.

    2015-01-01

    A new simple framework was proposed to quantify the efficiency of converting incoming solar radiation into phytoenergy in annual crops. It emphasizes the need to account for (i) efficiency gain when scaling up from the leaf level to the canopy level, and (ii) efficiency loss due to incomplete canopy

  10. The Influence of Different Interstock Lengths of Minneola Tanjelo on Photosynthetic Parameters and Fruit Yield of Star Ruby Grapefruit

    Directory of Open Access Journals (Sweden)

    Bilge Yılmaz

    2014-05-01

    Full Text Available In this study, Minneola Tangelo hybrid, a cross of grapefruit and mandarin (Duncan grapefruit x Dancy mandarin, used as interstock to Star Ruby grapefruit with different lengths. Effects of different interstock lengths on fruit yield and quality, plant development and photosynthetic parameters were investigated. According to the results, different interstock lengths significantly affected fruit yield and size. The highest fruit yield was determined in T-M20-S whereas the lowest was on T-M5-S. The highest fruit size were determined in Star Ruby fruits on T-M5-S and T-M40-S whereas the lowest on T-M20-S and T-S (control. T-M40-S and T-M20-S treatments markedly reduced stem diameter and tree canopy in comparison to other treatments and control. Usage of different interstock lengths did not significantly affected some of fruit quality traits, net photosynthetic rate, stomatal conductance, leaf transpiration rate, leaf water usage efficiency and leaf chlorophyll concentration. In regards to seasonal changes, net photosynthetic rate were higher in spring and summer seasons then winter and fall seasons.

  11. The effect of Nitrogen on Radiation Use Efficiency and Growth indices of Maize Hybrids (Zea mays L. under Kermanshah Condition

    Directory of Open Access Journals (Sweden)

    M Ahmadi

    2018-02-01

    Full Text Available Introduction Dry matter produced by crops is a function of absorbed radiation and radiation use efficiency. Radiation use efficiency is an effective approach to quantify total dry matter accumulation. It is defined as biomass produced by plant for solar radiation absorbed during growing season. Radiation use efficiency is often calculated from the linear regression slope between total dry matter accumulation and cumulative solar radiation absorbed. It is affected by species, weather conditions, crop management, plant development stages, and the production of photosynthesis compounds. Among the factors of agronomic management, nitrogen fertilizer and crop species are the most important aspects that affect the radiation use efficiency. Therefore, by considering the fact that Kermanshah province has favorable condition in terms of more natural resources such as solar radiation, the aims of the present study were evaluation of nitrogen effect on radiation use efficiency, growth indices and yield of some current maize hybrids. Materials and Methods A split plot experiment was done based on randomized complete block design with 4 replications at 2014. Treatments were 4 levels of nitrogen fertilizer application (40%, 70%, 100% and 140% of the maize demand to nitrogen which based on the amount recommended by soil experiment equivalent to 138, 238, 350 and 483 kg.ha-1 of urea as main plots and 3 maize hybrids KSC-704, BC-678 and Simon as sub plots. Leaf area index and total dry matter yield measured during growing season. Crop growth rate and relative growth ratio calculated by differentiation from fitted equation on total dry matter yield data. In order to calculate radiation use efficiency, sunny hours for Kermanshah latitude obtained from the nearest weather station. Daily solar radiation simulated by the method cited by Goudriaan and Van Laar (1993 for growing season. The absorbed radiation in each stage obtained through the multiplication simulated

  12. Scaling leaf respiration with nitrogen and phosphorus in tropical forests across two continents.

    Science.gov (United States)

    Rowland, Lucy; Zaragoza-Castells, Joana; Bloomfield, Keith J; Turnbull, Matthew H; Bonal, Damien; Burban, Benoit; Salinas, Norma; Cosio, Eric; Metcalfe, Daniel J; Ford, Andrew; Phillips, Oliver L; Atkin, Owen K; Meir, Patrick

    2017-05-01

    Leaf dark respiration (R dark ) represents an important component controlling the carbon balance in tropical forests. Here, we test how nitrogen (N) and phosphorus (P) affect R dark and its relationship with photosynthesis using three widely separated tropical forests which differ in soil fertility. R dark was measured on 431 rainforest canopy trees, from 182 species, in French Guiana, Peru and Australia. The variation in R dark was examined in relation to leaf N and P content, leaf structure and maximum photosynthetic rates at ambient and saturating atmospheric CO 2 concentration. We found that the site with the lowest fertility (French Guiana) exhibited greater rates of R dark per unit leaf N, P and photosynthesis. The data from Australia, for which there were no phylogenetic overlaps with the samples from the South American sites, yielded the most distinct relationships of R dark with the measured leaf traits. Our data indicate that no single universal scaling relationship accounts for variation in R dark across this large biogeographical space. Variability between sites in the absolute rates of R dark and the R dark  : photosynthesis ratio were driven by variations in N- and P-use efficiency, which were related to both taxonomic and environmental variability. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  13. Using a Chlorophyll Meter to Evaluate the Nitrogen Leaf Content in Flue-Cured Tobacco (Nicotiana tabacum L.

    Directory of Open Access Journals (Sweden)

    Fabio Castelli

    2009-06-01

    Full Text Available In flue-cured tobacco N fertilizer is commonly applied during pre-planting, and very often applied again later as a growth-starter. It is generally held that the efficiency of N-fertilizer use can be improved by evaluating the leaf Nstatus after transplanting and until flowering stage. N use efficiency in this context does not refer merely to the yield but also to the quality, in the meanwhile minimizing the negative effects on the environment. To investigate these aspects, we evaluated the capacity of a Minolta model SPAD-502 chlorophyll meter to estimate the N-status in flue-cured tobacco. The aims was to verify if a relationship exists between SPAD readings and leaf N content, and if a single leaf, in a well defined stalk position, could represent the nitrogen content of the whole plant. During the years 1995 and 1996, a pot experiment was conducted using two flue-cured tobacco varieties. SPAD values, total chlorophyll, total N contents and leaf area were measured throughout the growing season, on each odd leaf stalk position. SPAD values were well-correlated with both total chlorophyll and total N leaf concentration, and the regression coefficients were higher when relationships were calculated on a leaf-area basis. For both relationships, SPAD-total chlorophyll and SPAD-total N, the best fittings were obtained with quadratic equations. One leaf stalk position alone is able to monitor the N-status of the whole plant during the first six weeks after transplanting, without distinction of year and variety effects. The SPAD measurement of one leaf per plant, throughout the vegetative growing season, is therefore a valid tool to test the N-status of the crop in a period when a required N supply is still effective.

  14. Monitoring and evaluation of need for nitrogen fertilizer topdressing for maize leaf chlorophyll readings and the relationship with grain yield

    Directory of Open Access Journals (Sweden)

    Maria Anita Gonçalves da Silva

    2011-08-01

    Full Text Available The study was carried out for two years in maize in succession to the wheat using no tillage system in a distroferric Red Latosol (Hapludox. Methods of management nitrogen fertilizer (120 kg ha-1 with ammonium sulphate were studied; the fertilizer was applied in maize sowing or in maize topdressing, and N with previous application in wheat sowing. In addition, leaf chlorophyll reading was used as an indicator for the need for topdressed nitrogen fertilizer. Nitrogen supply index (NSI was shown to be effective at predicting need for topdressed nitrogen fertilizer for maize. The application of N improved the yield of the maize independent of the management system. The flowering stage was carried out at the appropriate time in order to estimate the nitrogen nutrition state and yield of maize using the relative chlorophyll level (RIC.

  15. Leaf application of silicic acid to upland rice and corn

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Costa Crusciol

    2013-12-01

    Full Text Available This study aimed to evaluate the effect of Si (stabilized silicic acid, Silamol® leaf application on mineral nutrition and yield in upland rice and corn crops. The treatments were the control (without Si and Si foliar split spraying using 2 L ha-1 of the Silamol® commercial product, with 0.8% soluble Si as concentrated stabilized silicic acid. Silicon leaf application increased the concentrations of K, Ca and Si in rice and corn leaves, the number of panicles per m2 of rice and the number of grains per ear of corn; accordingly, the Si leaf application provided a higher grain yield in both crops.

  16. Effects of ozone on growth, yield and leaf gas exchange rates of four Bangladeshi cultivars of rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Akhtar, Nahid; Yamaguchi, Masahiro; Inada, Hidetoshi; Hoshino, Daiki; Kondo, Taisuke; Fukami, Motohiro; Funada, Ryo; Izuta, Takeshi

    2010-01-01

    To assess the effects of tropospheric O 3 on rice cultivated in Bangladesh, four Bangladeshi cultivars (BR11, BR14, BR28 and BR29) of rice (Oryza sativa L.) were exposed daily to charcoal-filtered air or O 3 at 60 and 100 nl l -1 (10:00-17:00) from 1 July to 28 November 2008. The whole-plant dry mass and grain yield per plant of the four cultivars were significantly reduced by the exposure to O 3 . The exposure to O 3 significantly reduced net photosynthetic rate of the 12th and flag leaves of the four cultivars. The sensitivity to O 3 of growth, yield and leaf gas exchange rates was not significantly different among the four cultivars. The present study suggests that the sensitivity to O 3 of yield of the four Bangladeshi rice cultivars is greater than that of American rice cultivars and is similar to that of Japanese rice cultivars and that O 3 may detrimentally affect rice production in Bangladesh. - Bangladeshi cultivars of rice are sensitive to O 3 below 100 ppb.

  17. The Effect of Vesicular Arbuscular Mycorrhizal (VAM on Yield and Yield Components of Three Sorghum (Sorghum bicolor Cultivars

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    A. Mehraban

    2012-10-01

    Full Text Available To evaluate the influence of vesicular arbuscular mycorrhizal (VAM on yield and yield components of three sorghum cultivars, a factorial experiment based randomized complete block design with four replications was carried out in 2007, at the Agricultural Research Center of Zahak, Iran. The treatments were different mycorrhiza species in three levels: without mycorrhiza (M1, Glomus etanicatum (M2 and G. mosseae(M3 and three cultivars of sorghum: local cultivars (C1, KGS25 (C2 and KGS29 (C3. The results showed that all of the traits measured were increased by inoculation of cultivars with mycorrhiza. The highest plant height (165.1 cm, stem diameter (1.61 cm, flag leaf length (27.22 cm, flag leaf width (3.67 cm and ear width (5.00 cm was obtained by inoculation of seed with Glumus etanicatum, and highest ear length (19.21 cm, ear number (2.51, seed number per ear (10252.11, 1000-seed weight (17.56 g and grain yield (1967.32 kg/ha by using Glumus mossea. The highest leaf width and length belonged to local cultivar, and the highest seed yield to KGS 29 cultivar. However, differences of other traits among sorghum cultivars were not significant. Based on the experimental results it can be concluded that highest grain yield may be obtained by inoculating seeds of KGS 29 with Glumus mossea.

  18. Effect of Nitrogen and Phosphorus on Yield and Yield Components of Sesame (Sesamumindicum L.)

    OpenAIRE

    Muhammad Ibrahim; Manzoor Hussain; Ahmad Khan; Yousaf Jamal; Muhammad Ali; Muhammad Faisal Anwar Malik

    2014-01-01

    Nitrogen is a structural component of chlorophyll and protein therefore adequate supply of nitrogen is beneficial for both carbohydrates and protein metabolism as it promotes cell division and cell enlargement, resulting in more leaf area and thus ensuring good seed and dry matter yield. Theexperiment entitled effect of nitrogen and phosphorus on yield and yield components of sesame were conducted at New Developmental Farm of the University of Agriculture Peshawar during kharif 2013. Randomiz...

  19. Stomatal clustering in Begonia associates with the kinetics of leaf gaseous exchange and influences water use efficiency.

    Science.gov (United States)

    Papanatsiou, Maria; Amtmann, Anna; Blatt, Michael R

    2017-04-01

    Stomata are microscopic pores formed by specialized cells in the leaf epidermis and permit gaseous exchange between the interior of the leaf and the atmosphere. Stomata in most plants are separated by at least one epidermal pavement cell and, individually, overlay a single substomatal cavity within the leaf. This spacing is thought to enhance stomatal function. Yet, there are several genera naturally exhibiting stomata in clusters and therefore deviating from the one-cell spacing rule with multiple stomata overlaying a single substomatal cavity. We made use of two Begonia species to investigate whether clustering of stomata alters guard cell dynamics and gas exchange under different light and dark treatments. Begonia plebeja, which forms stomatal clusters, exhibited enhanced kinetics of stomatal conductance and CO2 assimilation upon light stimuli that in turn were translated into greater water use efficiency. Our findings emphasize the importance of spacing in stomatal clusters for gaseous exchange and plant performance under environmentally limited conditions. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  20. Effect of Mulch and Water Stress on Some Physiological Traits, Yield Components and Grain Yield of Red Kidney bean (Phaseolus vulgaris L.

    Directory of Open Access Journals (Sweden)

    R Amini

    2016-02-01

    Full Text Available Introduction Water use in agricultural production as one of the most important environmental factors affecting plant growth and development, especially in arid and semi-arid climatic conditions of Iran is of special importance (21. One of the ways of alleviating water scarcity is by enhancing its use efficiency or productivity. Improving water use efficiency in arid and semi-arid areas depends on effective conservation of moisture and efficient use of limited water. Mulching is one of the management practices for increasing water use efficiency (WUE . Straw mulch is commonly used as mulch. Straw mulching has potential for increasing soil water storage (16. Mulches modify the microclimate and growing conditions of crops (16, conserve more water and increase water use efficiency (34. Red kidney bean (Phaseolus vulgaris L. is the most important food legume (25 and is an important source of proteins and minerals (28. The majority of red kidney bean production is under drought conditions, and thus yield reductions due to drought are very common (29. This research was carried out to evaluate the effect of wheat straw mulch and water stress on physiological traits, yield components and grain yield of red kidney bean cultivars. Materials and Methods A field experiment was conducted in 2012 at the Research Farm of the Faculty of Agriculture, University of Tabriz, Iran (latitude 38°05_N, longitude 46°17_E, altitude 1360 m above sea level. In order to investigate the effect of mulch on grain yield and yield components of red kidney bean (Phaseolus vulgaris L. cultivars at different water stress treatments, a factorial experiment was conducted based on RCB design with three replications. The factors were including water stress treatment (I1 and I2, irrigation after 60 and 120 mm evaporation from class A pan, respectively; mulch application at two levels (M1: (no mulch and M2: 2 ton ha-1 wheat straw mulch and red kidney bean cultivars including Akhtar and

  1. Effects of different on-farm management on yield and water use efficiency of Potato crop cultivated in semiarid environments under subsurface drip irrigation

    Science.gov (United States)

    Ghazouani, Hiba; Provenzano, Giuseppe; Rallo, Giovanni; Mguidiche, Amel; Douh, Boutheina; Boujelben, Abdelhamid

    2016-04-01

    In Tunisia the amount of water for irrigated agriculture is higher than about 80% of the total resource.The increasing population and the rising food demand, associated to the negative effects of climate change,make it crucial to adopt strategies aiming to improve water use efficiency (WUE). Moreover, the absence of an effective public policy for water management amplifies the imbalance between water supply and its demand. Despite improved irrigation technologies can enhance the efficiency of water distribution systems, to achieve environmental goals it is also necessaryto identify on-farm management strategies accounting for actual crop water requirement. The main objective of the paper was to assess the effects of different on-farm managementstrategies (irrigation scheduling and planting date) on yield and water use efficiency of Potato crop (Solanumtuberosum L.) irrigated with a subsurface drip system, under the semi-arid climate of central Tunisia. Experiments were carried out during three growing seasons (2012, 2014 and 2015) at the High Agronomic Institute of ChottMariem in Sousse, by considering different planting dates and irrigation depths, the latter scheduled according to the climate observed during the season. All the considered treatments received the same pesticide and fertilizer management. Experiments evidenced that the climatic variability characterizing the examined seasons (photoperiod, solar radiation and average temperature) affects considerably the crop phenological stages, and the late sowing shortens the crop cycle.It has also been demonstrated that Leaf Area Index (LAI) and crop yield resulted relatively higher for those treatments receiving larger amounts of seasonal water. Crop yield varied between 16.3 t/ha and 39.1 t/ha, with a trend linearly related to the ratio between the seasonal amount of water supplied (Irrigation, I and Precipitation, P) and the maximum crop evapotranspiration (ETm). The maximum crop yield was in particular

  2. Isolation of hardy and high-yielding mutants in citronella (Cymbopogon winterianus)

    International Nuclear Information System (INIS)

    Kole, C.R.

    1990-01-01

    Full text: Citronella bears an essential oil of medicinal and aromatic importance. But little has been done for its genetic improvement. It is a clonally propagated crop and the genetic variability is too low for effective selection. Besides, various reproductive anomalies limit the scope for cross-breeding. With this in view, a mutation induction experiment was conducted. This crop is mostly grown in marginal lands and hardy genotypes are required. Exposure of vegetative slips of an improved strain (KS-CW-S-I) to x-rays at 3,6 and 9kR paved the way for selection of 53 elite M 1 V 2 clumps on the basis of the yield component characters. Mass screening under minimal cultural practices in a drought-prone zone in Western Orissa (India) led to identification of 16 potentially hardy clones (OJC-12 from 3kR, OJC-1, 3, 11, 18 and 20 from 6kR and OJC-4, 5, 6, 15, 21, 22, 24, 26, 30 and 31 from 9kR). The clones were planted with 3 replications in mid-monsoon, established during the remaining months of monsoon and grown thereafter under minimal cultural practices, i.e. no manure, fertiliser, irrigation, weeding or plant protection. Data on yield of fresh leaf and oil extracted from fresh leaves were recorded at harvest 6 months after planting at 5 to 6 leaf stage. The results revealed a highly significant variation with regard to yield of both leaf and oil. Six clones out-yielded the mother line for leaf as well as oil, and two clones surpassed the mother line in leaf yield only. The performance of clone OJC-3 was particularly encouraging. With 1.25 kg/plant leaf, 9.63cc/plant oil it superseded the yield of the mother line and other cultivars of this species (all around 0.6 kg/plant leaf, 5cc/plant oil) even when grown with irrigation. (author)

  3. Evaluation of the Yield and Water Use Efficiency of the Cucumber Inside Greenhouses

    Directory of Open Access Journals (Sweden)

    Ahmed Abied Hamza

    2016-03-01

    Full Text Available The need to provide fresh and good quality products during long periods throughout the year lead to the adoption of using greenhouses technology, so protected cropping has become a very popular production system in horticulture especially nowadays in Iraq. Evaluation the crop’s yield, water use efficiency and the irrigation system performance became essential. The main objectives of this research were to evaluate the yield index and the water use efficiency for the cucumber inside the greenhouses, and evaluate the performance of the drip irrigation efficiency inside the greenhouses. To accomplish these goals an experiment was conducted in the field located in AL-Mahawil Township in Babylon province .A set of measurements were recorded daily inside the greenhouses planting with cucumber for two consecutive seasons 2014 and 2015 related to weather parameters, crop evapotranspiration, drip system’s performance, and crop’s production. From the conducted field work inside the greenhouses and the analysis of the field data, the following conclusions were withdrawn: daily cucumber’s crop evapotranspiration was measured using the watermarks sensors, the total crop evapotranspiration for the seasons 2014 and 2015 were: 218.21mm and 281.86mm, respectively. The increasing in the crop evapotranspiration was due to change in weather parameters inside the greenhouses. The cucumber’s yield index for seasons 2014 and 2015 was: 8.87 and 8.53 kg/m2, respectively, which was close values between the two seasons. In this study, the yield index was high comparing with others approaches. The water use efficiency for the seasons 2014 and 2015 were: 23.23 and 18.22 kg/m3, respectively, which were low values comparing with other approaches. The reduction in the water use efficiency was due to the huge quantities of water applied through the seasons. Additionally, the irrigation efficiency for the drip system in this study for the seasons 2014 and 2015 were: 65

  4. Future consequences of decreasing marginal production efficiency in the high-yielding dairy cow.

    Science.gov (United States)

    Moallem, U

    2016-04-01

    The objectives were to examine the gross and marginal production efficiencies in high-yielding dairy cows and the future consequences on dairy industry profitability. Data from 2 experiments were used in across-treatments analysis (n=82 mid-lactation multiparous Israeli-Holstein dairy cows). Milk yields, body weights (BW), and dry matter intakes (DMI) were recorded daily. In both experiments, cows were fed a diet containing 16.5 to 16.6% crude protein and net energy for lactation (NEL) at 1.61 Mcal/kg of dry matter (DM). The means of milk yield, BW, DMI, NEL intake, and energy required for maintenance were calculated individually over the whole study, and used to calculate gross and marginal efficiencies. Data were analyzed in 2 ways: (1) simple correlation between variables; and (2) cows were divided into 3 subgroups, designated low, moderate, and high DMI (LDMI, MDMI, and HDMI), according to actual DMI per day: ≤ 26 kg (n=27); >26 through 28.2 kg (n=28); and >28.2 kg (n=27). The phenotypic Pearson correlations among variables were analyzed, and the GLM procedure was used to test differences between subgroups. The relationships between milk and fat-corrected milk yields and the corresponding gross efficiencies were positive, whereas BW and gross production efficiency were negatively correlated. The marginal production efficiency from DM and energy consumed decreased with increasing DMI. The difference between BW gain as predicted by the National Research Council model (2001) and the present measurements increased with increasing DMI (r=0.68). The average calculated energy balances were 1.38, 2.28, and 4.20 Mcal/d (standard error of the mean=0.64) in the LDMI, MDMI, and HDMI groups, respectively. The marginal efficiency for milk yields from DMI or energy consumed was highest in LDMI, intermediate in MDMI, and lowest in HDMI. The predicted BW gains for the whole study period were 22.9, 37.9, and 75.8 kg for the LDMI, MDMI, and HDMI groups, respectively. The

  5. Deferral of leaf senescence and increased productivity in rice

    International Nuclear Information System (INIS)

    Biswas, A.K.; Choudhari, M.A.

    1978-01-01

    The effect of spraying of different hormones and nurtient solutions on plants at 3 developmental stages of growth of Jaya rice has been studied. Increased plant growth and leaf longevity have been correlated with increased yield of the crop. 32 P feeding experiments showed that major export of materials took place from flag leaf to grains, while various treatments with hormones and nutrients could modify this export by implicating other leaves as well. These data also support the increased yield and longevity of the top. (author)

  6. Defining Efficient Deficit Irrigation for Winegrape Cultivars Merlot and Cabernet Sauvignon under Semiarid Conditions

    Science.gov (United States)

    Efficient deficit irrigation balances enhanced berry attributes with acceptable reduction in yield. The present study relates pre and post-veraison midday leaf water potential with the growth and composition of east and west-facing berries. Two deficit irrigation treatments were applied over four g...

  7. Investigation of The Relationship Between Grain Yield with Physiological Parameters in Some Bread Wheat Varieties

    Directory of Open Access Journals (Sweden)

    Mehmet KARAMAN

    2015-08-01

    Full Text Available This study was conducted to analyze the relationships between grain yield with physiological parameters in some bread wheat varieties. For this purpose, ten bread wheat genotypes were grown in randomized complete block design with 3 replications under rainfall conditions in the experimental field of GAP International Agricultural Research and Training Center during the 2012-2013 growing season. The most high yielding varieties in this study, Pehlivan, Kate A-1, Cemre and Anapo, were observed as standing out in terms of flag leaf chlorophyll content (SPAD value, flag leaf ash ratio, leaf area index and grain filling period . The correlation analyses of the study showed positive and significant correlations between chlorophyll content of flag leaf at heading stage with chlorophyll content at flowering stage, between chlorophyll content of flag leaf at flowering and heading stages with chlorophyll content of flag leaf at milk stage and between grain filling rate with leaf area index, In addition, positive and significant correlations were identified between flag leaf ash ratio and NDVI reading prior to heading time with grain yield

  8. Assessing the effects of soil liming with dolomitic limestone and sugar foam on soil acidity, leaf nutrient contents, grape yield and must quality in a Mediterranean vineyard

    Energy Technology Data Exchange (ETDEWEB)

    Olego, M.A.; Visconti, F.; Quiroga, M.J.; Paz, J.M. De; Garzón-Jimeno, E.

    2016-11-01

    Aluminium toxicity has been recognized as one of the most common causes of reduced grape yields in vineyard acid soils. The main aim of this study was to evaluate the effect of two liming materials, i.e. dolomitic lime and sugar foam, on a vineyard cultivated in an acid soil. The effects were studied in two soil layers (0-30 and 30-60 cm), as well as on leaf nutrient contents, must quality properties and grape yield, in an agricultural soil dedicated to Vitis vinifera L. cv. ‘Mencía’ cultivation. Data management and analysis were performed using analysis of variance (ANOVA). As liming material, sugar foam was more efficient than dolomitic limestone because sugar foam promoted the highest decrease in soil acidity properties at the same calcium carbonate equivalent dose. However, potassium contents in vines organs, including leaves and berries, seemed to decrease as a consequence of liming, with a concomitant increase in must total acidity. Soil available phosphorus also decreased as a consequence of liming, especially with sugar foam, though no effects were observed in plants. For these reasons fertilization of this soil with K and P is recommended along with liming. Grape yields in limed soils increased, although non-significantly, by 30%. This research has therefore provided an important opportunity to advance in our understanding of the effects of liming on grape quality and production in acid soils. (Author)

  9. Leaf Potential Productivity at Different Canopy Levels in Densely-planted and Intermediately-thinned Apple Orchards

    Directory of Open Access Journals (Sweden)

    Ying SUN

    2016-07-01

    Full Text Available Most apple orchards in the apple production districts in China were densely planted with vigorous rootstocks during the 1980s. These orchards have suffered micro-environmental deterioration and loss of fruit quality because of the closed canopy. Modification of the densely-planted orchards is a priority in current apple production. Intermediate thinning is a basic technique used to transform densely-planted apple orchards in China. Our goal was to provide theoretical basis for studying the effect of thinning on the efficiency of photosynthetically active radiation (PAR, fruit quality, and yield. We measured leaf area, solar radiation, and leaf air exchange at different tree canopy levels and by fitting relevant photosynthetic models, vertical distribution characteristics of leaf photosynthetic potentials and PAR were analyzed in various levels within canopies in densely-planted and intermediately-thinned orchards. Intermediate thinning significantly improved the radiant environment inside the canopies. PAR distribution within the canopies in the intermediately-thinned orchard was better distributed than in the densely-planted orchards. The invalid space under 30.0% of relative photosynthetically active radiation (PARr was nearly zero in the intermediately-thinned orchard; but minimum PARr was 17.0% and the space under 0.30 of the relative height of the canopy was invalid for photosynthesis in the densely-planted orchard. The leaf photosynthetic efficiency in the intermediately-thinned orchard was improved. Photosynthetic rates (Pn at the middle and bottom levels of the canopy, respectively, were increased by 7.80% and 10.20% in the intermediately-thinned orchard. Leaf development, which influences photosynthetic potential, was closely related to the surrounding micro-environment, especially light. Leaf photosynthetic potentials were correlated with leaf nitrogen content (Nl and specific leaf weight (Ml at various levels of canopies. Compared

  10. The influence of leaf anatomy on the internal light environment and photosynthetic electron transport rate: exploration with a new leaf ray tracing model.

    Science.gov (United States)

    Xiao, Yi; Tholen, Danny; Zhu, Xin-Guang

    2016-11-01

    Leaf photosynthesis is determined by biochemical properties and anatomical features. Here we developed a three-dimensional leaf model that can be used to evaluate the internal light environment of a leaf and its implications for whole-leaf electron transport rates (J). This model includes (i) the basic components of a leaf, such as the epidermis, palisade and spongy tissues, as well as the physical dimensions and arrangements of cell walls, vacuoles and chloroplasts; and (ii) an efficient forward ray-tracing algorithm, predicting the internal light environment for light of wavelengths between 400 and 2500nm. We studied the influence of leaf anatomy and ambient light on internal light conditions and J The results show that (i) different chloroplasts can experience drastically different light conditions, even when they are located at the same distance from the leaf surface; (ii) bundle sheath extensions, which are strips of parenchyma, collenchyma or sclerenchyma cells connecting the vascular bundles with the epidermis, can influence photosynthetic light-use efficiency of leaves; and (iii) chloroplast positioning can also influence the light-use efficiency of leaves. Mechanisms underlying leaf internal light heterogeneity and implications of the heterogeneity for photoprotection and for the convexity of the light response curves are discussed. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  11. [Effects of organic-inorganic mixed fertilizers on rice yield and nitrogen use efficiency].

    Science.gov (United States)

    Zhang, Xiao-li; Meng, Lin; Wang, Qiu-jun; Luo, Jia; Huang, Qi-wei; Xu, Yang-chun; Yang, Xing-ming; Shen, Qi-rong

    2009-03-01

    A field experiment was carried to study the effects of organic-inorganic mixed fertilizers on rice yield, nitrogen (N) use efficiency, soil N supply, and soil microbial diversity. Rapeseed cake compost (RCC), pig manure compost (PMC), and Chinese medicine residue compost (MRC) were mixed with chemical N, P and K fertilizers. All the treatments except CK received the same rate of N. The results showed that all N fertilizer application treatments had higher rice yield (7918.8-9449.2 kg x hm(-2)) than the control (6947.9 kg x hm(-2)). Compared with that of chemical fertilizers (CF) treatment (7918.8 kg x hm(-2)), the yield of the three organic-inorganic mixed fertilizers treatments ranged in 8532.0-9449.2 kg x hm(-2), and the increment was 7.7%-19.3%. Compared with treatment CF, the treatments of organic-inorganic mixed fertilizers were significantly higher in N accumulation, N transportation efficiency, N recovery rate, agronomic N use efficiency, and physiological N use efficiency. These mixed fertilizers treatments promoted rice N uptake and improved soil N supply, and thus, increased N use efficiency, compared with treatments CF and CK. Neighbor joining analysis indicated that soil bacterial communities in the five treatments could be classified into three categories, i.e., CF and CK, PMC and MRC, and RCC, implying that the application of exogenous organic materials could affect soil bacterial communities, while applying chemical fertilizers had little effect on them.

  12. Growth and yield of corn hybrids in response to association with Azospirillum brasilense and nitrogen fertilization

    Directory of Open Access Journals (Sweden)

    Deniele Marini

    2015-02-01

    Full Text Available There is a growing interest in optimizing the positive effects of the association between Azospirillum bacteria and corn crop in order to reduce the use of nitrogen fertilizers. This study aimed to evaluate the inoculation efficiency of an A. brasilense-based commercial product in association with different rates of nitrogen fertilization in two corn genotypes. The experiment was arranged in a 2 x 2 x 5 factorial randomized block design, with four replications. The treatments consisted of two corn hybrids (30F53 and CD386; with and without inoculation with a commercial product based on A. brasilense and five nitrogen rates (0, 40, 80, 120 and 160 kg ha-1. The variables plant height, basal stem diameter, leaf area, shoot dry matter, leaf nitrogen content, length and diameter of the cob, weight of 100 grains and grain yield were evaluated. Inoculation with A. brasilense provided increases of 11 and 12% in leaf area and shoot dry matter, respectively. There were differences in the response of the corn hybrids for most variables and the increase in nitrogen supply provided increments in the growth and yield of corn.

  13. Effects of some growth regulating applications on leaf yield, raw ...

    African Journals Online (AJOL)

    Jane

    2011-06-22

    Jun 22, 2011 ... covering the region of Hadim-Aladağ, 59% of the soil in the region was ... 11.00 g diet fiber, 6.3 g sugar, 9 mg sodium, 363.08 mg calcium, 2.63 g ... Inst. Inc., Canada), and leaf volume was determined by dipping the samples into ... prepared by applying the wet burning method and in these plant extracts, P ...

  14. Yield and water use efficiency of deficit-irrigated maize in a semi ...

    African Journals Online (AJOL)

    Yield and water use efficiency of deficit-irrigated maize in a semi-arid region of Ethiopia. ... PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN JOURNALS ONLINE ... African Journal of Food, Agriculture, Nutrition and Development.

  15. Stomatal conductance, mesophyll conductance, and trans piration efficiency in relation to leaf anatomy in rice and wheat genotypes under drought

    NARCIS (Netherlands)

    Ouyang, Wenjing; Struik, Paul C.; Yin, Xinyou; Yang, Jianchang

    2017-01-01

    Increasing leaf transpiration efficiency (TE) may provide leads for growing rice like dryland cereals such as wheat (Triticum aestivum). To explore avenues for improving TE in rice, variations in stomatal conductance (g s) and mesophyll conductance (g m) and their anatomical determinants were

  16. Fungicides efficiency on wheat diseases control in response to the application with different spray nozzles

    Directory of Open Access Journals (Sweden)

    Felipe Rafael Garcés Fiallos

    2011-12-01

    Full Text Available This study aimed to evaluate the efficiency of fungicides to leaf control diseases of wheat, when applied to different models of spray nozzles. The experiment was conducted in a randomized block design with four replicates of factorial (4 x 3+1. Data were subjected to analysis of variance and means compared by Tukey test at 5% probability. The fungicides used were: Opera® (pyraclostrobin+epoxiconazole 0.75 L.ha-1 , Opera® 0.75 L.ha-1 +Folicur® (tebuconazole 0.3 L.ha-1 , Priori Xtra® (azoxystrobin+cyproconazole 0.3 L.ha-1 , Priori Xtra® 0.3 L.ha-1 +Tilt® (propiconazole 0.3 L.ha-1 . These fungicides were applied with three models of spray nozzles jet planes: XR 11 001 (fine drop, AIRMIX 11,001 (average drop and AVI 11,001 (coarse drop. We evaluated the incidence and severity (damage per plant leaf of yellow spot (Drechslera tritici-repentis, spot blotch (Bipolaris sorokiniana, leaf rust (Puccinia triticina and grain yield (kg.ha-1 culture. The results show that the application of fungicides for control of leaf diseases in wheat resulted in increases in grain yield, and yield higher values were observed with the application of Opera®, using the XR 11001.

  17. Effect of Olive Leaf ( Powder on Laying Hens Performance, Egg Quality and Egg Yolk Cholesterol Levels

    Directory of Open Access Journals (Sweden)

    H. Cayan

    2015-04-01

    Full Text Available This experiment was conducted to measure the effects of olive leaf powder on performance, egg yield, egg quality and yolk cholesterol level of laying hens. A total of 120 Lohmann Brown laying hens of 22 weeks old were used in this experiment. The birds were fed on standard layer diets containing 0, 1%, 2%, or 3% olive leaf powder for 8 weeks. Egg weight and yield were recorded daily; feed intake weekly; egg quality and cholesterol content at the end of the trial. Olive leaf powder had no effect on feed intake, egg weight, egg yield and feed conversion ratio (p>0.05 while olive leaf powder increased final body weight of hens (p0.05. To conclude, olive leaf powder can be used for reducing egg yolk cholesterol content and egg yolk coloring agent in layer diets.

  18. Yields, photosynthetic efficiencies, and proximate chemical composition of dense cultures of marine microalgae. A subcontract report

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, W.H.; Seibert, D.L.R.; Alden, M.; Eldridge, P.; Neori, A.

    1983-07-01

    The yields, photosynthetic efficiencies, and proximate composition of several microalgae were compared in dense cultures grown at light intensities up to 70% sunlight. Yields ranged from 3.4 to 21.7 g dry weight/m/sup 2/ day. The highest yield was obtained with Phaeodactylum; the lowest in Botryococcus cultures. The same species had the highest and lowest efficiencies of utilization of photosynthetically active radiation. In nitrogen-sufficient cells of all but one species, most of the dry weight consisted of protein. Lipid content of all species was 20 to 29%, and carbohydrate content 11 to 23%. Lipid content increased somewhat in N-deficient Phaeodactylum and Isochrysis cells, but decreased in deficient Monallanthus cells. Because the overall dry weight yield was reduced by deficiency, lipid yields did not increase. However, since the carbohydrate content increased to about 65% in N-deficient Dunaliella and Tetraselmis cells, the carbohydrate yield increased. In Phaeodactylum the optimum light intensity was about 40% of full sunlight. Most experimets with this alga included a CUSO/sub 4/ filter to decrease infrared irradiance. When this filter was removed, the yield increased because more red light in the photosynthetically active spectral range was included. These results should prove useful to workers attempting to maximize yields and efficiencies, but additional studies are needed. 69 references, 27 figures, 18 tables.

  19. Probabilities for profitable fungicide use against gray leaf spot in hybrid maize.

    Science.gov (United States)

    Munkvold, G P; Martinson, C A; Shriver, J M; Dixon, P M

    2001-05-01

    ABSTRACT Gray leaf spot, caused by the fungus Cercospora zeae-maydis, causes considerable yield losses in hybrid maize grown in the north-central United States and elsewhere. Nonchemical management tactics have not adequately prevented these losses. The probability of profitably using fungicide application as a management tool for gray leaf spot was evaluated in 10 field experiments under conditions of natural inoculum in Iowa. Gray leaf spot severity in untreated control plots ranged from 2.6 to 72.8% for the ear leaf and from 3.0 to 7.7 (1 to 9 scale) for whole-plot ratings. In each experiment, fungicide applications with propiconazole or mancozeb significantly reduced gray leaf spot severity. Fungicide treatment significantly (P yield by as much as 1.65 t/ha with a single propiconazole application. There were significant (P < 0.05) correlations between gray leaf spot severity and yield. We used a Bayesian inference method to calculate for each experiment the probability of achieving a positive net return with one or two propiconazole applications, based on the mean yields and standard deviations for treated and untreated plots, the price of grain, and the costs of the fungicide applications. For one application, the probability ranged from approximately 0.06 to more than 0.99, and exceeded 0.50 in six of nine scenarios (specific experiment/hybrid). The highest probabilities occurred in the 1995 experiments with the most susceptible hybrid. Probabilities were almost always higher for a single application of propiconazole than for two applications. These results indicate that a single application of propiconazole frequently can be profitable for gray leaf spot management in Iowa, but the probability of a profitable application is strongly influenced by hybrid susceptibility. The calculation of probabilities for positive net returns was more informative than mean separation in terms of assessing the economic success of the fungicide applications.

  20. [Effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash].

    Science.gov (United States)

    Du, She-ni; Bai, Gang-shuan; Liang, Yin-li

    2011-04-01

    A pot experiment with artificial shading was conducted to study the effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash variety "Jingyingyihao". Under all test soil moisture conditions, 30% shading promoted the growth of "Jingyingyihao", with the highest yield at 70% - 80% soil relative moisture contents. 70% shading inhibited plant growth severely, only flowering and not bearing fruits, no economic yield produced. In all treatments, there was a similar water consumption trend, i. e., both the daily and the total water consumption decreased with increasing shading and decreasing soil moisture content. Among all treatments, 30% shading and 70% - 80% soil relative moisture contents had the highest water use efficiency (2.36 kg mm(-1) hm(-2)) and water output rate (1.57 kg mm(-1) hm(-2)). The net photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll content of squash leaves decreased with increasing shading, whereas the intercellular CO2 concentration was in adverse. The leaf protective enzyme activity and proline content decreased with increasing shading, and the leaf MAD content decreased in the order of 70% shading, natural radiation, and 30% shading. Under the three light intensities, the change characteristics of squash leaf photosynthesis, protective enzyme activity, and proline and MAD contents differed with the increase of soil relative moisture content.

  1. Relationship of leaf oxygen and carbon isotopic composition with transpiration efficiency in the C4 grasses Setaria viridis and Setaria italica.

    Science.gov (United States)

    Ellsworth, Patrick Z; Ellsworth, Patrícia V; Cousins, Asaph B

    2017-06-15

    Leaf carbon and oxygen isotope ratios can potentially provide a time-integrated proxy for stomatal conductance (gs) and transpiration rate (E), and can be used to estimate transpiration efficiency (TE). In this study, we found significant relationships of bulk leaf carbon isotopic signature (δ13CBL) and bulk leaf oxygen enrichment above source water (Δ18OBL) with gas exchange and TE in the model C4 grasses Setaria viridis and S. italica. Leaf δ13C had strong relationships with E, gs, water use, biomass, and TE. Additionally, the consistent difference in δ13CBL between well-watered and water-limited plants suggests that δ13CBL is effective in separating C4 plants with different availability of water. Alternatively, the use of Δ18OBL as a proxy for E and TE in S. viridis and S. italica was problematic. First, the oxygen isotopic composition of source water, used to calculate leaf water enrichment (Δ18OLW), was variable with time and differed across water treatments. Second, water limitations changed leaf size and masked the relationship of Δ18OLW and Δ18OBL with E. Therefore, the data collected here suggest that δ13CBL but not Δ18OBL may be an effective proxy for TE in C4 grasses. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  2. Diallel analyze of yield and progress of the severity of leaf diseases in maize hybrids in two population density

    Directory of Open Access Journals (Sweden)

    Marcos Ventura Faria

    2015-02-01

    Full Text Available Seven commercial maize hybrids (AS1575, 2B688, Penta, GNZ2004, AG8021, Sprint e P30F53 were intercrossed in a complete diallel, excluded reciprocal, obtaining 21 crosses. The 28 treatments were evaluated in two environments characterized by different densities (62,500 and 90,000 plants ha-1, with the aim of selecting the most promising parents for generating base population to obtain lines. Two experiments were carried out in Guarapuava-PR, at randomized block design with three replications. We estimated the general (GCA and specific (SCA combining abilities for yield and disease severity assessed by the area under the common rust (Puccinia sorghi progress curve (AURPC and the area under the leaf spot (Cercospora zeae-maydis progress curve (AULPC. The effects of GCA and SCA were significant for grain yield and diseases severity in both densities, revealing the importance of both additive and non-additive effects. There GCA x densities interaction was significant only for grain yield. Crossings P30F53 x AG8021 and P30F53 x Penta had negative estimates of SCA for AURPC and AULPC on the environments average. Hybrids GNZ 2004 and P30F53 stood out showing positive GCA for grain yield and negative for AURPC and AULPC in both densities and therefore are recommended for generating base populations for obtaining lines adapted for both densities, conventional and denser plantings, given the current trends in management of maize.

  3. Teaching the relation between solar cell efficiency and annual energy yield

    International Nuclear Information System (INIS)

    Sark, Wilfried G J H M van

    2007-01-01

    To reach a sustainable world the use of renewable energy sources is imperative. Photovoltaics (PV) is but one of the technologies that use the power of the sun and its deployment is growing very fast. Several master programs have been developed over the world, including Utrecht University, that teach these technologies. Within the framework of a course on energy conversion technologies, we have developed a classroom problem that focuses on the difference between PV efficiency and annual yield for the two locations: the Utrecht University campus and the African Sahara desert. In spreadsheet format, students calculate annual yield, and they find a best method to do so. The exercise can be done in about three hours, and students will learn that the annual yield in the Sahara is only twice that at Utrecht University,

  4. Induction of resistance to bacterial leaf blight (Xanthomonas oryzae) disease in the high yielding variety Vijaya (IR 8 x T 90)

    International Nuclear Information System (INIS)

    Padmanabhan, S.Y.; Kaur, S.; Rao, M.

    1976-01-01

    The high-yield variety Vijaya ( IR 8 x T 90), susceptible to bacterial leaf blight (Xanthomonas oryzae, Uyeda and Ishiyama Dawson), was treated with EMS to induce resistance. Dehusked seeds were pre-soaked in distilled water for 4 hrs, and subjected to 0.1% and 0.2% EMS for 6 hrs. Seed germination and survival was low in 0.2% EMS. Seedlings of M 1 were raised in pots, and panicles of individual plants harvested separately. The seeds of M 2 (8800 plants) generation were grown in nursery beds, and transplanted in field after 30 days. The plants were inoculated at the boot leaf stage with X.oryzae by the clipping method, and lesion length measured 15 days later. The frequency distribution of controls was bimodal, the EMS-treated population polymodal with new peaks. A wider range of variability was induced on the resistant and susceptible side. In M 2 0.36% resistant and 0.62% moderately resistant plants occurred. The seeds of (11) resistant and (20) moderately resistant plants of M 2 were sown for M 3 generation. These plants also segregated in the range of 0-31 and 0-32 cm lesion length. The frequency distribution curve was polymodal. M 2 from ''R'' showed 1.07% of resistant plants and 0.42% from ''MR'', against, 4.28% of moderately resistant plants from ''R'' and 3.22% from ''MR''. Susceptible plants of M 2 also segregated towards resistance (1.15%) and moderately resistant (6.96%) plants in M 3 generation. Resistant (25) and moderately resistant (147) plants of M 3 were carried forward to M 4 generation, and segregated in the range of 2.1-25 cm lesion length. The frequency curve was polymodal. No resistant plant (up to 2.0 cm lesion length) could be isolated in M 4 . The percentage of moderately resistant plants was 4.44% from ''R'' of M 3 and 4.82% from ''MR'' of M 3 and 4.77% from ''S'' of M 3 generation. The yield of resistant plants was low whereas the yield of moderately resistant plants equalled the parent; the yield of susceptible segregants equalled or

  5. Effect of Wind on the Relation of Leaf N, P Stoichiometry with Leaf Morphology in Quercus Species

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2018-02-01

    Full Text Available Leaf nitrogen (N and phosphorus (P stoichiometry correlates closely to leaf morphology, which is strongly impacted by wind at multiple scales. However, it is not clear how leaf N, P stoichiometry and its relationship to leaf morphology changes with wind load. We determined the leaf N and P concentrations and leaf morphology—including specific leaf area (SLA and leaf dissection index (LDI—for eight Quercus species under a simulated wind load for seven months. Leaf N and P concentrations increased significantly under these conditions for Quercus acutissima, Quercus rubra, Quercus texana, and Quercus palustris—which have elliptic leaves—due to their higher N, P requirements and a resultant leaf biomass decrease, which is a tolerance strategy for Quercus species under a wind load. Leaf N:P was relatively stable under wind for all species, which supports stoichiometric homeostasis. Leaf N concentrations showed a positive correlation to SLA, leaf N and P concentrations showed positive correlations to LDI under each wind treatment, and the slope of correlations was not affected by wind, which indicates synchronous variations between leaf stoichiometry and leaf morphology under wind. However, the intercept of correlations was affected by wind, and leaf N and P use efficiency decreased under the wind load, which suggests that the Quercus species changes from “fast investment-return” in the control to “slow investment-return” under windy conditions. These results will be valuable to understanding functional strategies for plants under varying wind loads, especially synchronous variations in leaf traits along a wind gradient.

  6. Homeostasis in leaf water potentials on leeward and windward sides of desert shrub crowns: water loss control vs. high hydraulic efficiency.

    Science.gov (United States)

    Iogna, Patricia A; Bucci, Sandra J; Scholz, Fabián G; Goldstein, Guillermo

    2013-11-01

    Phenotypic plasticity in morphophysiological leaf traits in response to wind was studied in two dominant shrub species of the Patagonian steppe, used as model systems for understanding effects of high wind speed on leaf water relations and hydraulic properties of small woody plants. Morpho-anatomical traits, hydraulic conductance and conductivity and water relations in leaves of wind-exposed and protected crown sides were examined during the summer with nearly continuous high winds. Although exposed sides of the crowns were subjected to higher wind speeds and air saturation deficits than the protected sides, leaves throughout the crown had similar minimum leaf water potential (ΨL). The two species were able to maintain homeostasis in minimum ΨL using different physiological mechanisms. Berberis microphylla avoided a decrease in the minimum ΨL in the exposed side of the crown by reducing water loss by stomatal control, loss of cell turgor and low epidermal conductance. Colliguaja integerrima increased leaf water transport efficiency to maintain transpiration rates without increasing the driving force for water loss in the wind-exposed crown side. Leaf physiological changes within the crown help to prevent the decrease of minimum ΨL and thus contribute to the maintenance of homeostasis, assuring the hydraulic integrity of the plant under unfavorable conditions. The responses of leaf traits that contribute to mechanical resistance (leaf mass per area and thickness) differed from those of large physiological traits by exhibiting low phenotypic plasticity. The results of this study help us to understand the unique properties of shrubs which have different hydraulic architecture compared to trees.

  7. Agronomic Characteristics Related to Grain Yield and Nutrient Use Efficiency for Wheat Production in China.

    Directory of Open Access Journals (Sweden)

    Limin Chuan

    Full Text Available In order to make clear the recent status and trend of wheat (Triticum aestivum L. production in China, datasets from multiple field experiments and published literature were collected to study the agronomic characteristics related to grain yield, fertilizer application and nutrient use efficiency from the year 2000 to 2011. The results showed that the mean grain yield of wheat in 2000-2011 was 5950 kg/ha, while the N, P2O5 and K2O application rates were 172, 102 and 91 kg/ha on average, respectively. The decrease in N and P2O5 and increase in K2O balanced the nutrient supply and was the main reason for yield increase. The partial factor productivity (PFP, kg grain yield produced per unit of N, P2O5 or K2O applied values of N (PFP-N, P (PFP-P and K (PFP-K were in the ranges of 29.5~39.6, 43.4~74.9 and 44.1~76.5 kg/kg, respectively. While PFP-N showed no significant changes from 2000 to 2010, both PFP-P and PFP-K showed an increased trend over this period. The mean agronomic efficiency (AE, kg grain yield increased per unit of N, P2O5 or K2O applied values of N (AEN, P (AEP and K (AEK were 9.4, 10.2 and 6.5 kg/kg, respectively. The AE values demonstrated marked inter-annual fluctuations, with the amplitude of fluctuation for AEN greater than those for AEP and AEK. The mean fertilizer recovery efficiency (RE, the fraction of nutrient uptake in aboveground plant dry matter to the nutrient of fertilizer application values of N, P and K in the aboveground biomass were 33.1%, 24.3% and 28.4%, respectively. It was also revealed that different wheat ecological regions differ greatly in wheat productivity, fertilizer application and nutrient use efficiency. In summary, it was suggested that best nutrient management practices, i.e. fertilizer recommendation applied based on soil testing or yield response, with strategies to match the nutrient input with realistic yield and demand, or provided with the 4R's nutrient management (right time, right rate, right

  8. Photosynthetic rate, dry matter accumulation and yield inter-relationships jn genotypes of rice

    International Nuclear Information System (INIS)

    Devendra, R.; Udaya Kumar, M.; Krishna Sastry, K.S.

    1980-01-01

    The relationship between photosynthetic efficiency, dry matter accumulation and yield in five genotypes of paddy derived from a single cross between Jaya X Halubbalu was studied. Photosynthetic efficiency of younger leaves, on the main tiller was higher than in the older leaves. A significant positive correlation between RuDPcase activity and photosynthetic efficiency was observed in these genotypes. Also a similar positive correlation between dry matter production and photosynthetic efficiency during vegetative period but not during post-anthesis period was observed. Genotypes with high photosynthetic efficiency and also the genotypes with high LAD produced higher dry matter. A reduction in LAD or in photosynthetic efficiency during the post-anthesis period and thus a reduction in source capacity which occurred specially in late types resulted in a lesser ratio between productive and total tillers and also higher percent sterility. Differences in yield amongst the genotypes were not significant, since in the late types MR. 333 and MR. 335, the post-anthesis dry matter production was low due to lesser source capacity. But in the early types, though the total dry matter was less, the post-anthesis source capacity was high. The importance of post-anthesis leaf area of photo-synthetic efficiency in productivity in genotypes of rice is highlighted. (author)

  9. Wheat-yield response to irrigation and nitrogen

    International Nuclear Information System (INIS)

    Kirda, C.; Derici, R.; Kanber, R.; Yazar, A.; Koc, M.; Barutcular, C.

    2000-01-01

    Wheat-yield responses to the application of different rates of N fertilizer, under irrigated and rainfed conditions, were evaluated over four growing seasons. Nitrogen applied at tillering was utilized more effectively with proportionately less residual in the soil compared to that applied at planting. Subsequent crops of maize or cotton were positively affected by residual fertilizer N. Volatilization and leaching losses of applied N were small. Crop-water consumption showed strong positive associations with N rate. No wheat-grain-yield benefits accrued from irrigation, although straw yields were increased. Tiller production increased with N-fertilizer usage, however, tiller survival decreased at high N and was highest at 160 kg N ha -1 . Higher N rates produced higher stomatal conductance, increased rates of CO 2 assimilation and higher water-use efficiency. The CERES-Wheat growth-simulation model predicted rather closely the progress of dry-matter production, leaf area index, seasonal evapotranspiration, phenological development and of many other plant-growth attributes. The data indicated that the rate of 160 kg N ha -1 , which is commonly used by the farmers of the region, is acceptable, not only for optimum grain yields but also to minimize the risks of leaching NO 3 - to groundwater. (author)

  10. Effects of Organic and Chemical Fertilizers on Leaf Yield, Essential Oil Content and Composition of Lemon Verbena (Lippia citriodora Kunth

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Ebadi

    2017-02-01

    Full Text Available Introduction: Organic fertilizers with beneficial effects on soil structure and nutrient availability help maintain yield and quality, and they are less costly than synthetic fertilizers. Vermicompost and vermiwash are two organic fertilizers that they contain a biologically active mixture of bacteria, enzymes and phytohormones, also these organic fertilizers can supply the nutritional needs of plants. Lemon verbena (Lippia citriodora Kunth, Verbenaceae is an evergreen perennial aromatic plant. The lemon-scented essential oil from the lemon verbena has been widely used for its digestive, relaxing, antimalarial and lemony flavor properties. In order to decrease the use of chemical fertilizers for reduction of environmental pollution, this research was undertaken to determine effects of vermicompost and vermiwash in comparison with chemical fertilizer on leaf yield, essential oil content and composition of lemon verbena. Materials and Methods: A pot experiment based on a completely randomized design with six treatments and three replications on Lemon verbena was carried out in the experimental greenhouse of the Department of Horticulture Sciences, Tarbiat Modares University, 2012. Treatments consisted of 10, 20 and 30 % by volume of vermicompost and vermiwash (with an addition to irrigation in three steps, including: two weeks after the establishment of plants in pots, the appearing of branches and three weeks before harvest, complete fertilizer and control without any fertilizer. Each replication contained six pots and each pot contained one plant of Lemon verbena provided from Institute of Medicinal Plants, Karaj, therefore 108 pots were used in this experiment. The pots were filled up by a mixture contained 3/5 soil and 2/5 sand (v/v. After three months, plant aerial parts were harvested concomitantly at starting of the flowering stage. Aerial parts were dried at room temperature for 72 hours and dry weights of dried branches and leaves were

  11. Natural Pineapple Leaf Fibre Extraction On Josapine And Morris

    OpenAIRE

    Mazalan Muhammad Firdaus; Yusof Yusri

    2017-01-01

    The pineapple’s leaf plant contains approximately 2.5% to 3.5% of strong white silky fibres. These fibres are useful and can be extracted from the leaves. There are a few ways to extract the fibre such as hand scrapping and by extraction machine. The objective of this research is to study the quality of fibre extraction by using different age of pineapple leaf. Next, the study aims to compare the quality of Josapine and Morris pineapple leaf with tensile test. Fibre yield percentage are calcu...

  12. Effect of Different Plastic mulch on Growth and Yield of Potato (Solanum tuberosum

    Directory of Open Access Journals (Sweden)

    khosro parvizi

    2018-02-01

    Full Text Available Introduction: The advantages of plastic mulches have been known in production of agricultural crops. Their capability have been demonstrated to help nutrition uptake, precocity and yield of fruit trees, and decreasing of aphid population as viruses pest vectors. It is also demonstrated some advantages of plastic mulch on some traits in potato such as increasing growth rate, yield and number of medium tuber size. Also, the effects of combined use of straw, chopped and polyethylene as well as different levels of irrigation (60, 80, 100, 120% water requirement on yield and water use efficiency in potato have been investigated. In previous studies, it is concentrated on the effect of the special type of plastic on growing aspect of potato and there is no comparative assessment between different types of the mulches. So that in this research we evaluated the responses between types of plastic mulches. Material and Methods: this research was conducted under field conditions. A factorial experiment was designed based on randomized complete block design with three replications. The experimental treatments consisted of mulch in five levels (clear, white, black, double layer and control (without mulch and two cultivars (Agria and Sante. Each plot was designed in 4 m2. For every plot, ridges were divided into complicated double rows with 50 × 150 centimeters wide. Irrigation tapes were placed between every duplicated row. Water requirement was calculated through corrected evapotranspiration (ETo by Penman-Monteith equation with considering 90% water use efficiency. During the growing season some characteristics such as requirement time to 80% emergence, tuberization time, plant height in flowering time, number of stems and leaf area have been measured. Harvesting time was recorded along with measurement of tuber weights. Total yield was measured by random selection of one m2 in each plot. Harvested tubers were separated based on three sizes; edible tuber

  13. Selection of drought tolerant and high water use efficient rice cultivars through /sup 13/C isotope discrimination technique

    International Nuclear Information System (INIS)

    Akhtar, J.; Sabir, S.A.; Ashraf, M.Y.; Monneveux, P.; Serraj, R.

    2010-01-01

    Carbon isotope discrimination ('A') has been suggested as an indirect tool for selecting plants having higher water use efficiency (WUE) and yield potential. Enhancing WUE is an important breeding objective as water scarcity is increasing with every passing day. This study was undertaken to assess the genotypic variation and relationship between leaf, straw, grain 'A', grain yield and WUE in eight aromatic rice cultivars grown in lysimeters under three water regimes, in absence of drainage and runoff. Highly significant positive correlations were found between aboveground biomass and WUEB, and grain yield and WUEG, due to the low variation in water consumed by different cultivars. Leaf, straw and grain A showed a consistent variation across treatments and cultivars. Under water stress conditions, both leaf and straw 'A' were positively correlated to grain yield and WUEG. In all the water treatments, WUEG was positively correlated to harvest index and negatively to plant height. All the mutants from Basmati 385 had significantly higher 'A' values as compared to the mutants from Basmati 370. It was concluded that the new cultivar, Basmati 385, represents a better genetic source for 'A' improvement than the old cultivar, Basmati 370. (author)

  14. Growth Performance of Clarias Gariepinus Fed Soaked Moringa Oleifera Leaf Meal

    OpenAIRE

    Ayegba, E. O

    2016-01-01

    The present study evaluates the nutritional potential of soaked-dried Moringa oleifera leaf meal in the diet of Clarias gariepinus. Four isonitrogenous (35% crude protein) diets were formulated with Moringa leaf replacing soybean meal at 0%, 10%, 20% and 30%. Result obtained revealed declined in weight gain, specific growth rate, feed conversion efficiency, protein efficiency ratio and apparent net protein utilization as dietary replacement of Moringa leaf meal increased beyond 10%. It is con...

  15. Leaf area prediction models for Tsuga canadensis in Maine

    Science.gov (United States)

    Laura S. Kenefic; R.S. Seymour

    1999-01-01

    Tsuga canadensis (L.) Carr. (eastern hemlock) is a common species throughout the Acadian forest. Studies of leaf area and growth efficiency in this forest type have been limited by the lack of equations to predict leaf area of this species. We found that sapwood area was an effective leaf area surrogate in T. canadensis, though...

  16. Post-weaning feed efficiency decreased in progeny of higher milk yielding beef cows.

    Science.gov (United States)

    Mulliniks, J T; Edwards, S R; Hobbs, J D; McFarlane, Z D; Cope, E R

    2018-02-01

    Current trends in the beef industry focus on selecting production traits with the purpose of maximizing calf weaning weight; however, such traits may ultimately decrease overall post-weaning productivity. Therefore, the objective of this study was to evaluate the effects of actual milk yield in mature beef cows on their offspring's dry matter intake (DMI), BW, average daily gain, feed conversion ratio (FCR) and residual feed intake (RFI) during a ~75-day backgrounding feeding trial. A period of 24-h milk production was measured with a modified weigh-suckle-weigh technique using a milking machine. After milking, cows were retrospectively classified as one of three milk yield groups: Lower (6.57±1.21 kg), Moderate (9.02±0.60 kg) or Higher (11.97±1.46 kg). Calves from Moderate and Higher milk yielding dams had greater (Pfeeding phase; however, day 75 BW were not different (P=0.36) between Lower and Moderate calves. Body weight gain was greater (P=0.05) for Lower and Moderate calves from the day 0 BW to day 35 BW compared with Higher calves. Overall DMI was lower (P=0.03) in offspring from Lower and Moderate cows compared with their Higher milking counterparts. With the decreased DMI, FCR was lower (P=0.03) from day 0 to day 35 in calves from Lower and Moderate milk yielding dams. In addition, overall FCR was lower (P=0.02) in calves from Lower and Moderate milk yielding dams compared with calves from Higher milk yielding dams. However, calving of Lower milk yielding dams had an increased (P=0.04) efficiency from a negative RFI value compared with calves from Moderate and Higher milking dams. Results from this study suggest that increased milk production in beef cows decreases feed efficiency during a 75-day post-weaning, backgrounding period of progeny.

  17. Effects of Controlled-Release Urea on Grain Yield of Spring Maize, Nitrogen Use Efficiency and Nitrogen Balance

    Directory of Open Access Journals (Sweden)

    JI Jing-hong

    2017-03-01

    Full Text Available The effects of mixing controlled-released urea (CRU (release period of resin coated urea is 90 days and urea (U on maize yield, nitrogen use efficiency and nitrogen balance were studied by 4 plot experiments (site:Shuangcheng, Binxian, Harbin and Zhaoyuan in two years (from year 2011 to 2012 to clarify the effect of controlled release urea on spring maize and soil nitrogen balance. Results were as follow:Spring maize yield and nitrogen absorption were increased with the increasing nitrogen fertilizer. Compared with applying urea treatment, applying CRU could increase yield, nitrogen absorption, nitrogen use efficiency, agriculture efficiency of nitrogen and nitrogen contribution rate. Under the same amount of nitrogen (100%, 75%, 50%, compared with 100% U as basic fertilizer treatment, maize yield of 100% CRU treatment increased 391, 427, 291 kg·hm-2, nitrogen use efficiency increased by 5.9%,4.9% and 5.1%, agriculture efficiency of nitrogen increased 2.0, 2.6, 2.6 kg·kg-1, and nitrogen contribution rate increased 2.7%, 3.1% and 2.4%, respectively. The value of maize yield, nitrogen absorption, nitrogen use efficiency and agriculture efficiency of nitrogen between the treatment four (40% urea as basic fertilizer+60% urea as topdressing and treatment five (40% urea plus 60% controlled release urea as basic fertilizer were similar. Apparent profit and loss of nitrogen decreased with the increase of nitrogen nitrogen fertilizer. Nitrogen apparent loss by applying 100% controlled release urea was reduced of 15.0 kg·hm-2 than applying 100% U treatment;Nitrogen apparent loss amount was decreased of 23.9 kg·hm-2 under treatment five. The method of mixing 40% urea and 60% controlled release urea should be applied in maize production in Heilongjiang Province.

  18. Quantitative trait loci associated with resistance to gray leaf spot and grain yield in corn QTLs associados à resistência a cercosporiose e produção de grãos em milho

    Directory of Open Access Journals (Sweden)

    Adriano Delly Veiga

    2012-02-01

    Full Text Available The main objectives of hybrid development programs include incorporating genetic resistance to diseases and increasing grain yield. Identification of Quantitative Trait Loci (QTL through the statistical analysis of molecular markers allows efficient selection of resistant and productive hybrids. The objective of this research was to identify QTL associated with resistance to gray leaf spot and for grain yield in the germplasm of tropical corn. We used two strains with different degrees of reaction to the disease; the genotypes are owned by GENESEEDS Ltda, their F1 hybrid and the F2 population. The plants were evaluated for gray leaf spot resistance, for grain yield and were genotyped with 94 microsatellite markers. Association of the markers with the QTL was performed by single marker analysis using linear regression and maximum likelihood analysis. It was observed that the additive effect was predominant for genetic control of resistance to gray leaf spot, and the dominant effect in that of grain yield. The most promising markers to be used in studies of assisted selection are: umc2082 in bins 4.03 and umc1117 in bins 4.04 for resistance to gray leaf spot; for grain yield umc1042 in bins 2.07 and umc1058 in bins 4.11.A incorporação de resistência genética a doenças e o aumento na produtividade de grãos estão entre os principais objetivos dos programas de desenvolvimento de híbridos. A identificação de locos de caracteres quantitativos (QTL por meio de análises estatísticas associadas a marcadores moleculares possibilita a rápida obtenção de híbridos resistentes e produtivos. Nesta pesquisa, objetivou-se identificar locos de caracteres quantitativos (QTL associados com resistência à cercosporiose e com produção de grãos em germoplasma de milho tropical. Foram utilizadas duas linhagens contrastantes em níveis de reação à doença (genótipos pertencentes à GENESEEDS - Ltda, seu híbrido F1 e a população segregante F2

  19. Effect of water stress on total biomass, tuber yield, harvest index and water use efficiency in Jerusalem artichoke

    Science.gov (United States)

    The objectives of this study were to determine the effect of drought on tuber yield, total biomass, harvest index, water use efficiency of tuber yield (WUEt) and water use efficiency of biomass (WUEb), and to evaluate the differential responses of Jerusalem artichoke (JA) varieties under drought str...

  20. Genetic basis of nitrogen use efficiency and yield stability across environments in winter rapeseed.

    Science.gov (United States)

    Bouchet, Anne-Sophie; Laperche, Anne; Bissuel-Belaygue, Christine; Baron, Cécile; Morice, Jérôme; Rousseau-Gueutin, Mathieu; Dheu, Jean-Eric; George, Pierre; Pinochet, Xavier; Foubert, Thomas; Maes, Olivier; Dugué, Damien; Guinot, Florent; Nesi, Nathalie

    2016-09-15

    Nitrogen use efficiency is an important breeding trait that can be modified to improve the sustainability of many crop species used in agriculture. Rapeseed is a major oil crop with low nitrogen use efficiency, making its production highly dependent on nitrogen input. This complex trait is suspected to be sensitive to genotype × environment interactions, especially genotype × nitrogen interactions. Therefore, phenotyping diverse rapeseed populations under a dense network of trials is a powerful approach to study nitrogen use efficiency in this crop. The present study aimed to determine the quantitative trait loci (QTL) associated with yield in winter oilseed rape and to assess the stability of these regions under contrasting nitrogen conditions for the purpose of increasing nitrogen use efficiency. Genome-wide association studies and linkage analyses were performed on two diversity sets and two doubled-haploid populations. These populations were densely genotyped, and yield-related traits were scored in a multi-environment design including seven French locations, six growing seasons (2009 to 2014) and two nitrogen nutrition levels (optimal versus limited). Very few genotype × nitrogen interactions were detected, and a large proportion of the QTL were stable across nitrogen nutrition conditions. In contrast, strong genotype × trial interactions in which most of the QTL were specific to a single trial were found. To obtain further insight into the QTL × environment interactions, genetic analyses of ecovalence were performed to identify the genomic regions contributing to the genotype × nitrogen and genotype × trial interactions. Fifty-one critical genomic regions contributing to the additive genetic control of yield-associated traits were identified, and the structural organization of these regions in the genome was investigated. Our results demonstrated that the effect of the trial was greater than the effect of nitrogen nutrition

  1. Effects of Vermi-compost Fertilizer Application and Foliar Spraying on Yield and Yield Component of Isabgol (Plantago ovate L. Medicinal Plant

    Directory of Open Access Journals (Sweden)

    Asghar Rahimi

    2017-12-01

    Full Text Available Introduction Vermi-compost is the ability of some species of earthworms to consume and break down a wide range of organic residues such as sewage sludge, animal wastes, crop residues and industrial refuse. Vermi-composts are usually more stable than their parent materials with increased availability of nutrients and improved physicochemical and microbiological properties. Aerial compost tea contains high populations of live microorganism consisting of rhizobactria, trichoderma and pseudomonas species which increase the growth and yield of the plant. Acid humic is the main humic substance and the important ingredient of soil organic matter (humus which causes increase of yield and quality of crop. The aim of this research is evaluating the effect of vermi-compost and foliar application of compost tea and acid humic on yield, yield component and mucilage content of isabgol. Vermiwash as the extract of vermi-compost is liquid organic fertilizer obtained from unit of vermiculture and vermi-compost as drainage. It is used as a foliar spraying on the leaf. Vermiwash stimulate and increase the yield of crop products and foliar application of vermiwash can be caused of plant resistance to different factors and can prevent leaf necrosis. Material and Methods In order to study the effect of vermi-compost and foliar application of tea compost and acid humic on growth indices of isabgol (Plantago ovata, an experiment was conducted as a factorial based on complete randomized design with three replications in agricultural research farm at Vali-e-Asr University of Rafsanjan. Treatments were included application of vermi-compost (0 (control, 4, 8, 12 and 16 t.ha-1 and 3 levels of foliar application (distilled water as control, acid humic and compost tea. Samples for evaluating of yield, yield components and mucilage content were taken from 1 m2 area of each treatment. Tea compost solution prepared using mix of vermi-compost, acid humic, yeast and alga extract

  2. Impact of controlled release urea on maize yield and nitrogen use efficiency under different water conditions.

    Directory of Open Access Journals (Sweden)

    Guanghao Li

    Full Text Available Controlled release urea (CRU has been widely adopted to increase nitrogen (N use efficiency and maize production, but the impacts can range widely depending on water availability in the soil. In an experiment using Zhengdan 958 (a popular summer maize hybrid, three levels of water treatments (adequate water condition [W3], which maintained soil moisture at about 75% ± 5% of the soil's field capacity; mild water stress [W2], which maintained moisture content at 55% ± 5% of field capacity; and severe water stress [W1], which had a moisture content of 35% ± 5% of field capacity and four levels of controlled release urea fertilizer (N0, N1, N2 and N3 were 0, 105, 210 and 315 kg N ha-1, respectively were compared in a rainout shelter system with soil. The results revealed that CRU had significant effects on maize yields and N use efficiencies under different water conditions. The mean yields increased with increasing water levels and showed significant differences. Under W1, the accumulation of dry matter and N were limited, and N internal efficiency (NIE and the apparent recovery efficiency of applied N (REN decreased with N increases; yields of N1, N2, and N3 were similar. Under W2, the dry matter and N accumulation, as well as the yield, showed an increasing trend with an increase in N application, and the NIE and REN of N3 showed no difference from N2. Under W3, yields of N2 and N3 were similar and they were significantly higher than that of N1, but the agronomic N use efficiency (ANUE, REN, and the physiological NUE (PNUE of N2 were 54.2, 34.9, and 14.4% higher, respectively, than those of N3. N application beyond the optimal N rate did not consistently increase maize yield, and caused a decrease in N use efficiencies. Highest overall dry matter, N accumulation, and yields were observed with N3 under W2, and those showed no differences with N2 and N3 under W3. Under this experimental condition, the CRU of 210 kg ha-1 was optimized when soil

  3. Effects of nitrogen application rate on dry matter redistribution, grain yield, nitrogen use efficiency and photosynthesis in malting barley

    DEFF Research Database (Denmark)

    Cai, J; Jiang, D; Wollenweber, Bernd

    2012-01-01

    The harmonious combination of malting barley yield, quality and nitrogen (N) use-efficiency under nitrogen (N) rates applications was greatly conducive to production in China. The malting barley cultivar Supi 3 was planted during the growing seasons 2005 and 2006 at two contrasting sites in China....... Five nitrogen (N) application rates (0, 75, 150, 225 and 300 kg ha−1) were applied for research of effects of N rates application on grain yield, protein content and N use-efficiency. At both sites and in both years, grain yield increased with increasing N application rates up to 225 kg N ha−1...... with a quadrant model, the optimum N application rates for high grain yield with high nitrogen use-efficiency in malting barley could be indicated. So, the higher yields could be mainly ascribed to the higher accumulation of photoassimilates between anthesis and maturity. In order to achieve high grain yield...

  4. The Effect of Organic and Inorganic Sources of Fertiliser on Growth and Yield of Brassica Oleraceae var. Acephala D.C

    International Nuclear Information System (INIS)

    Onyango, M.O.A.; Onyango, J.C.

    1999-01-01

    Kale (Brassica oleraceae var. Acephala D.C.) cultivar, collard green was planted in the field between October 1997 and March 1998 in the experimental plots at Maseno University college in Western Kenya. The experiment was set up to study the effect of organic and inorganic sources of fertiliser on growth and yield of kale. The kale seedlings were first raised in a nursery and transplanted 8 weeks after sowing. The treatments included farm yard manure (150 kg N.ha -1 , 8kgP.ha -1 ), Tithonia Diversifolia (Tithonia) Leaf biomass incorporated in combination with Diammonium phosphate (DAP) (150kgN.ha -1 and 30kgP.ha -1 ), TSithonia leaf biomass incorporated, DAP in combination with Urea, DAP in combination with calcium Ammonium nitrate (CAN) at the rate of 150kgP.ha -1 and the control. Non-destructive measurements on plant height, leaf number and stem thickness were taken regularly commencing 6 weeks after transplanting. Leaf yield was assessed by both cumulative leaf weight per given area and leaf number per plant. Both organic and inorganic sources of fertiliser significantly increased growth and leaf yield of kale. In all parameters measured farm yard manure gave the best response. Tithonia leaf biomass incorporated in the soil either on its own or in combination with DAP gave leaf yields comparable increasing, organic sources which are locally available to the farmer can be alternative sources of fertiliser without compromising the yields

  5. Different growing conditions affect nutrient content, fruit yield and growth in strawberry

    International Nuclear Information System (INIS)

    Demirsory, L.; Demirsoy, H.; Balci, G.

    2011-01-01

    This study aimed to determine the effects of organic and conventional growing on contents of some nutrient elements, nitrogen (N), phosphorous (P), potassium (K), iron (Fe), and manganese (Mn), yield and some growth parameters such as leaf area, petiole length, petiole diameter, crown number, crow n diameter, leaf, root dry weight in 'Sweet Charlie' and 'Camarosa' strawberry cultivars. This study consisted of two strawberry cultivars ('Camarosa' and 'Sweet Charlie'), two growing systems (organic and conventional growing) and two different mulches (black and floating sheet). There was significant difference among treatments in terms of P, K, and Mn content in root and Fe content in leaf and yield and some growth parameters. The best treatment in terms of yield and growth parameters was conventional growing with black plastic in 'Camarosa' while the best treatments were organic growing with floating sheet and black plastic in 'Sweet Charlie' in terms of P, K in root and organic growing with floating sheet in 'Sweet Charlie' in terms of Fe in leaf. (author)

  6. Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China

    OpenAIRE

    Xu, Xinpeng; Liu, Xiaoyan; He, Ping; Johnston, Adrian M.; Zhao, Shicheng; Qiu, Shaojun; Zhou, Wei

    2015-01-01

    Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L.) were collected in four m...

  7. Vapour pressure deficit during growth has little impact on genotypic differences of transpiration efficiency at leaf and whole-plant level: an example from Populus nigra L.

    Science.gov (United States)

    Rasheed, Fahad; Dreyer, Erwin; Richard, Béatrice; Brignolas, Franck; Brendel, Oliver; Le Thiec, Didier

    2015-04-01

    Poplar genotypes differ in transpiration efficiency (TE) at leaf and whole-plant level under similar conditions. We tested whether atmospheric vapour pressure deficit (VPD) affected TE to the same extent across genotypes. Six Populus nigra genotypes were grown under two VPD. We recorded (1) (13)C content in soluble sugars; (2) (18)O enrichment in leaf water; (3) leaf-level gas exchange; and (4) whole-plant biomass accumulation and water use. Whole-plant and intrinsic leaf TE and (13)C content in soluble sugars differed significantly among genotypes. Stomatal conductance contributed more to these differences than net CO2 assimilation rate. VPD increased water use and reduced whole-plant TE. It increased intrinsic leaf-level TE due to a decline in stomatal conductance. It also promoted higher (18)O enrichment in leaf water. VPD had no genotype-specific effect. We detected a deviation in the relationship between (13)C in leaf sugars and (13)C predicted from gas exchange and the standard discrimination model. This may be partly due to genotypic differences in mesophyll conductance, and to its lack of sensitivity to VPD. Leaf-level (13)C discrimination was a powerful predictor of the genetic variability of whole-plant TE irrespective of VPD during growth. © 2014 John Wiley & Sons Ltd.

  8. Translational researches on leaf senescence for enhancing plant productivity and quality.

    Science.gov (United States)

    Guo, Yongfeng; Gan, Su-Sheng

    2014-07-01

    Leaf senescence is a very important trait that limits yield and biomass accumulation of agronomic crops and reduces post-harvest performance and the nutritional value of horticultural crops. Significant advance in physiological and molecular understanding of leaf senescence has made it possible to devise ways of manipulating leaf senescence for agricultural improvement. There are three major strategies in this regard: (i) plant hormone biology-based leaf senescence manipulation technology, the senescence-specific gene promoter-directed IPT system in particular; (ii) leaf senescence-specific transcription factor biology-based technology; and (iii) translation initiation factor biology-based technology. Among the first strategy, the P SAG12 -IPT autoregulatory senescence inhibition system has been widely explored and successfully used in a variety of plant species for manipulating senescence. The vast majority of the related research articles (more than 2000) showed that crops harbouring the autoregulatory system displayed a significant delay in leaf senescence without any abnormalities in growth and development, a marked increase in grain yield and biomass, dramatic improvement in horticultural performance, and/or enhanced tolerance to drought stress. This technology is approaching commercialization. The transcription factor biology-based and translation initiation factor biology-based technologies have also been shown to be very promising and have great potentials for manipulating leaf senescence in crops. Finally, it is speculated that technologies based on the molecular understanding of nutrient recycling during leaf senescence are highly desirable and are expected to be developed in future translational leaf senescence research. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. High yield CTMP fibres as a possibility of the more efficient yield of wood raw material

    Directory of Open Access Journals (Sweden)

    Klašnja Bojana A.

    2004-01-01

    Full Text Available The evident shortage of wood as a raw material has become a limiting factor in the pulp and paper industry which is the greatest consumer of wood in Europe. The situation in our country is similar. During the few past years, the production of poplar and willow pulpwood was 220.000 m3 per year, which is insufficient for the planned increase in the production of sulphate pulp (175.000 tons till 2005. This paper deals with the aspects of the more efficient yield of raw material, based on the significantly higher yield of CTMP fibres, as well as with the significance of the lower adverse effect on the environment. It also analyses the conditions of production and the quality of the obtained fibres, as a possible substitute for chemical pulp and secondary fibres in papers of different quality. The main reasons for the production and use of CTMP fibres in our country are reported.

  10. Increased SBPase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions.

    Science.gov (United States)

    Driever, Steven M; Simkin, Andrew J; Alotaibi, Saqer; Fisk, Stuart J; Madgwick, Pippa J; Sparks, Caroline A; Jones, Huw D; Lawson, Tracy; Parry, Martin A J; Raines, Christine A

    2017-09-26

    To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf photosynthesis in wheat, the level of the Calvin-Benson cycle enzyme sedoheptulose-1,7-biphosphatase (SBPase) has been increased through transformation and expression of a Brachypodium distachyon SBPase gene construct. Transgenic lines with increased SBPase protein levels and activity were grown under greenhouse conditions and showed enhanced leaf photosynthesis and increased total biomass and dry seed yield. This showed the potential of improving yield potential by increasing leaf photosynthesis in a crop species such as wheat. The results are discussed with regard to future strategies for further improvement of photosynthesis in wheat.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Authors.

  11. Soil water effect on crop growth, leaf gas exchange, water and radiation use efficiency of Saccharum spontaneum L. ssp. aegyptiacum (Willd. Hackel in semi-arid Mediterranean environment

    Directory of Open Access Journals (Sweden)

    Danilo Scordia

    2015-12-01

    Full Text Available Great effort has been placed to identify the most suited bioenergy crop under different environments and management practices, however, there is still need to find new genetic resources for constrained areas. For instance, South Mediterranean area is strongly affected by prolonged drought, high vapour pressure deficit (VPD and extremely high temperatures during summertime. In the present work we investigated the soil water effect on crop growth and leaf gas exchange of Saccharum spontaneum L. ssp. aegyptiacum (Willd. Hackel, a perennial, rhizomatous, herbaceous grass. Furthermore, the net increase of biomass production per unit light intercepted [radiation use efficiency (RUE] and per unit water transpired [water use efficiency (WUE] was also studied. To this end a field trial was carried out imposing three levels of soil water availability (I100, I50 and I0, corresponding to 100%, 50% and 0% of ETm restutition under a semi-arid Mediterranean environment. Leaf area index (LAI, stem height, biomass dry matter yield, CO2 assimilation rate, and transpiration rate resulted significantly affected by measurement time and irrigation treatment, with the highest values in I100 and the lowest in I0. RUE was the highest in I100 followed by I50 and I0; on the other hand, WUE was higher in I0 than I50 and I100. At LAI values greater than 2.0, 85% photosynthetically active radiation was intercepted by the Saccharum stand, irrespective of the irrigation treatment. Saccharum spontaneum spp. aegyptiacum is a potential species for biomass production in environment characterized by drought stress, high temperatures and high VPD, as those of Southern Europe and similar semi-arid areas.

  12. Use of NAP gene to manipulate leaf senescence in plants

    Science.gov (United States)

    Gan, Susheng; Guo, Yongfeng

    2013-04-16

    The present invention discloses transgenic plants having an altered level of NAP protein compared to that of a non-transgenic plant, where the transgenic plants display an altered leaf senescence phenotype relative to a non-transgenic plant, as well as mutant plants comprising an inactivated NAP gene, where mutant plants display a delayed leaf senescence phenotype compared to that of a non-mutant plant. The present invention also discloses methods for delaying leaf senescence in a plant, as well as methods of making a mutant plant having a decreased level of NAP protein compared to that of a non-mutant plant, where the mutant plant displays a delayed leaf senescence phenotype relative to a non-mutant plant. Methods for causing precocious leaf senescence or promoting leaf senescence in a plant are also disclosed. Also disclosed are methods of identifying a candidate plant suitable for breeding that displays a delayed leaf senescence and/or enhanced yield phenotype.

  13. Influence of leaf vein density and thickness on hydraulic conductance and photosynthesis in rice (Oryza sativa L.) during water stress.

    Science.gov (United States)

    Tabassum, Muhammad Adnan; Zhu, Guanglong; Hafeez, Abdul; Wahid, Muhammad Atif; Shaban, Muhammad; Li, Yong

    2016-11-16

    The leaf venation architecture is an ideal, highly structured and efficient irrigation system in plant leaves. Leaf vein density (LVD) and vein thickness are the two major properties of this system. Leaf laminae carry out photosynthesis to harvest the maximum biological yield. It is still unknown whether the LVD and/or leaf vein thickness determines the plant hydraulic conductance (K plant ) and leaf photosynthetic rate (A). To investigate this topic, the current study was conducted with two varieties under three PEG-induced water deficit stress (PEG-IWDS) levels. The results showed that PEG-IWDS significantly decreased A, stomatal conductance (g s ), and K plant in both cultivars, though the IR-64 strain showed more severe decreases than the Hanyou-3 strain. PEG-IWDS significantly decreased the major vein thickness, while it had no significant effect on LVD. A, g s and K plant were positively correlated with each other, and they were negatively correlated with LVD. A, g s and K plant were positively correlated with the inter-vein distance and major vein thickness. Therefore, the decreased photosynthesis and hydraulic conductance in rice plants under water deficit conditions are related to the decrease in the major vein thickness.

  14. Comparison of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship between spatial density of plants and total leaf area per plant.

    Science.gov (United States)

    Shi, Pei-Jian; Xu, Qiang; Sandhu, Hardev S; Gielis, Johan; Ding, Yu-Long; Li, Hua-Rong; Dong, Xiao-Bo

    2015-10-01

    The relationship between spatial density and size of plants is an important topic in plant ecology. The self-thinning rule suggests a -3/2 power between average biomass and density or a -1/2 power between stand yield and density. However, the self-thinning rule based on total leaf area per plant and density of plants has been neglected presumably because of the lack of a method that can accurately estimate the total leaf area per plant. We aimed to find the relationship between spatial density of plants and total leaf area per plant. We also attempted to provide a novel model for accurately describing the leaf shape of bamboos. We proposed a simplified Gielis equation with only two parameters to describe the leaf shape of bamboos one model parameter represented the overall ratio of leaf width to leaf length. Using this method, we compared some leaf parameters (leaf shape, number of leaves per plant, ratio of total leaf weight to aboveground weight per plant, and total leaf area per plant) of four bamboo species of genus Indocalamus Nakai (I. pedalis (Keng) P.C. Keng, I. pumilus Q.H. Dai and C.F. Keng, I. barbatus McClure, and I. victorialis P.C. Keng). We also explored the possible correlation between spatial density and total leaf area per plant using log-linear regression. We found that the simplified Gielis equation fit the leaf shape of four bamboo species very well. Although all these four species belonged to the same genus, there were still significant differences in leaf shape. Significant differences also existed in leaf area per plant, ratio of leaf weight to aboveground weight per plant, and leaf length. In addition, we found that the total leaf area per plant decreased with increased spatial density. Therefore, we directly demonstrated the self-thinning rule to improve light interception.

  15. High transpiration efficiency increases pod yield under intermittent drought in dry and hot atmospheric conditions but less so under wetter and cooler conditions in groundnut (Arachis hypogaea (L.)).

    Science.gov (United States)

    Vadez, Vincent; Ratnakumar, Pasala

    2016-07-01

    Water limitation is a major yield limiting factor in groundnut and transpiration efficiency (TE) is considered the main target for improvement, but TE being difficult to measure it has mostly been screened with surrogates. The paper re-explore the contribution of TE to grain yield in peanut by using a novel experimental approach in which TE is measured gravimetrically throughout the crop life cycle, in addition to measurement of TE surrogates. Experimentation was carried out with the groundnut reference collection (n = 288), across seasons varying for the evaporative demand (vapor pressure deficit, VPD) and across both fully irrigated and intermittent water stress conditions. There was large genotypic variation for TE under water stress in both low and high VPD season but the range was larger (5-fold) in the high- than in the low-VPD season (2-fold). Under water stress in both seasons, yield was closely related to the harvest index (HI) while TE related directly to yield only in the high VPD season. After discounting the direct HI effect on yield, TE explained a large portion of the remaining yield variations in both seasons, although marginally in the low VPD season. By contrast, the total water extracted from the soil profile, which varied between genotypes, did not relate directly to pod yield and neither to the yield residuals unexplained by HI. Surrogates for TE (specific leaf area, SLA, and SPAD chlorophyll meter readings, SCMR) never showed any significant correlation to TE measurements. Therefore, TE is an important factor explaining yield differences in groundnut under high VPD environments, suggesting that stomatal regulation under high VPD, rather than high photosynthetic rate as proposed earlier, may have a key role to play in the large TE differences found, which open new opportunities to breed improved groundnut for high VPD.

  16. Optimal leaf sequencing with elimination of tongue-and-groove underdosage

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, Srijit [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Sahni, Sartaj [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Palta, Jatinder [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Ranka, Sanjay [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Li, Jonathan [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)

    2004-02-07

    The individual leaves of a multileaf collimator (MLC) have a tongue-and-groove or stepped-edge design to minimize leakage radiation between adjacent leaves. This design element has a drawback in that it creates areas of underdosages in intensity-modulated photon beams unless a leaf trajectory is specifically designed such that for any two adjacent leaf pairs, the direct exposure under the tongue-and-groove is equal to the lower of the direct exposures of the leaf pairs. In this work, we present a systematic study of the optimization of a leaf sequencing algorithm for segmental multileaf collimator beam delivery that completely eliminates areas of underdosages due to tongue-and-groove or stepped-edge design of the MLC. Simultaneous elimination of tongue-and-groove effect and leaf interdigitation is also studied. This is an extension of our previous work (Kamath et al 2003a Phys. Med. Biol. 48 307) in which we described a leaf sequencing algorithm that is optimal for monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation. Compared to our previously published algorithm (without constraints), the new algorithms increase the number of sub-fields by approximately 21% and 25%, respectively, but are optimal in MU efficiency for unidirectional schedules. (note)

  17. Optimal leaf sequencing with elimination of tongue-and-groove underdosage

    International Nuclear Information System (INIS)

    Kamath, Srijit; Sahni, Sartaj; Palta, Jatinder; Ranka, Sanjay; Li, Jonathan

    2004-01-01

    The individual leaves of a multileaf collimator (MLC) have a tongue-and-groove or stepped-edge design to minimize leakage radiation between adjacent leaves. This design element has a drawback in that it creates areas of underdosages in intensity-modulated photon beams unless a leaf trajectory is specifically designed such that for any two adjacent leaf pairs, the direct exposure under the tongue-and-groove is equal to the lower of the direct exposures of the leaf pairs. In this work, we present a systematic study of the optimization of a leaf sequencing algorithm for segmental multileaf collimator beam delivery that completely eliminates areas of underdosages due to tongue-and-groove or stepped-edge design of the MLC. Simultaneous elimination of tongue-and-groove effect and leaf interdigitation is also studied. This is an extension of our previous work (Kamath et al 2003a Phys. Med. Biol. 48 307) in which we described a leaf sequencing algorithm that is optimal for monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation. Compared to our previously published algorithm (without constraints), the new algorithms increase the number of sub-fields by approximately 21% and 25%, respectively, but are optimal in MU efficiency for unidirectional schedules. (note)

  18. Status of Sugarcane yellow leaf virus and its impact in different progenies

    Science.gov (United States)

    Yellow leaf disease caused by Sugarcane yellow leaf virus (SCYLV) a Polerovirus is an important disease for sugarcane industries worldwide. High yield losses up to 50% were reported in susceptible varieties. Most of the commercial cultivars in Florida are infected with SCYLV; therefore, there is a ...

  19. Effects of limited irrigation on yield and water use efficiency of two ...

    African Journals Online (AJOL)

    The effects of irrigation on grain yield and water use efficiency was studied on two sequence replaced dryland winter wheat (Triticum aestivum L.) cultivars, Changwu 135 (CW, a new cultivar) and Pingliang 40 (PL, an old cultivar). Field experiments were carried out on Changwu country on Loess Plateau, China. Whereas ...

  20. Do the rich always become richer? Characterizing the leaf physiological response of the high-yielding rice cultivar Takanari to free-air CO2 enrichment.

    Science.gov (United States)

    Chen, Charles P; Sakai, Hidemitsu; Tokida, Takeshi; Usui, Yasuhiro; Nakamura, Hirofumi; Hasegawa, Toshihiro

    2014-02-01

    The development of crops which are well suited to growth under future environmental conditions such as higher atmospheric CO2 concentrations ([CO2]) is essential to meeting the challenge of ensuring food security in the face of the growing human population and changing climate. A high-yielding indica rice variety (Oryza sativa L. cv. Takanari) has been recently identified as a potential candidate for such breeding, due to its high productivity in present [CO2]. To test if it could further increase its productivity under elevated [CO2] (eCO2), Takanari was grown in the paddy field under season-long free-air CO2 enrichment (FACE, approximately 200 µmol mol(-1) above ambient [CO2]) and its leaf physiology was compared with the representative japonica variety 'Koshihikari'. Takanari showed consistently higher midday photosynthesis and stomatal conductance than Koshihikari under both ambient and FACE growth conditions over 2 years. Maximum ribulose-1,5-bisphosphate carboxylation and electron transport rates were higher for Takanari at the mid-grain filling stage in both years. Mesophyll conductance was higher in Takanari than in Koshihikari at the late grain-filling stage. In contrast to Koshihikari, Takanari grown under FACE conditions showed no decrease in total leaf nitrogen on an area basis relative to ambient-grown plants. Chl content was higher in Takanari than in Koshihikari at the same leaf nitrogen level. These results indicate that Takanari maintains its superiority over Koshihikari in regards to its leaf-level productivity when grown in elevated [CO2] and it may be a valuable resource for rice breeding programs which seek to increase crop productivity under current and future [CO2].

  1. Extracellular synthesis of silver nanoparticles using the leaf extract of Coleus amboinicus Lour

    Energy Technology Data Exchange (ETDEWEB)

    Narayanan, Kannan Badri [Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605014 (India); Sakthivel, Natarajan, E-mail: puns2005@gmail.com [Department of Biotechnology, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605014 (India)

    2011-10-15

    Highlights: {yields} Synthesis of AgNPs using the leaf extract of Coleus amboinicus L. was described. {yields} UV-vis absorption spectra showed the formation of isotrophic AgNPs at 437 nm in 6 h. {yields} XRD analysis showed intense peaks corresponding to fcc structure of AgNPs. {yields} HR-TEM analysis revealed the formation of stable anisotrophic and isotrophic AgNPs. -- Abstract: In the present investigation, Coleus amboinicus Lour. leaf extract-mediated green chemistry approach for the synthesis of silver nanoparticles was described. The nanoparticles were characterized by ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The influence of leaf extract on the control of size and shape of silver nanoparticles is reported. Upon an increase in the concentration of leaf extract, there was a shift in the shape of nanoparticles from anisotrophic nanostructures like triangle, decahedral and hexagonal to isotrophic spherical nanoparticles. Crystalline nature of fcc structured nanoparticles was confirmed by XRD spectrum with peaks corresponding to (1 1 1), (2 0 0), (2 2 0) and (3 1 1) planes and bright circular spots in the selected-area electron diffraction (SAED). Such environment friendly and sustainable methods are non-toxic, cheap and alternative to hazardous chemical procedures.

  2. Transcriptional analyses of natural leaf senescence in maize.

    Directory of Open Access Journals (Sweden)

    Wei Yang Zhang

    Full Text Available Leaf senescence is an important biological process that contributes to grain yield in crops. To study the molecular mechanisms underlying natural leaf senescence, we harvested three different developmental ear leaves of maize, mature leaves (ML, early senescent leaves (ESL, and later senescent leaves (LSL, and analyzed transcriptional changes using RNA-sequencing. Three sets of data, ESL vs. ML, LSL vs. ML, and LSL vs. ESL, were compared, respectively. In total, 4,552 genes were identified as differentially expressed. Functional classification placed these genes into 18 categories including protein metabolism, transporters, and signal transduction. At the early stage of leaf senescence, genes involved in aromatic amino acids (AAAs biosynthetic process and transport, cellular polysaccharide biosynthetic process, and the cell wall macromolecule catabolic process, were up-regulated. Whereas, genes involved in amino acid metabolism, transport, apoptosis, and response to stimulus were up-regulated at the late stage of leaf senescence. Further analyses reveals that the transport-related genes at the early stage of leaf senescence potentially take part in enzyme and amino acid transport and the genes upregulated at the late stage are involved in sugar transport, indicating nutrient recycling mainly takes place at the late stage of leaf senescence. Comparison between the data of natural leaf senescence in this study and previously reported data for Arabidopsis implies that the mechanisms of leaf senescence in maize are basically similar to those in Arabidopsis. A comparison of natural and induced leaf senescence in maize was performed. Athough many basic biological processes involved in senescence occur in both types of leaf senescence, 78.07% of differentially expressed genes in natural leaf senescence were not identifiable in induced leaf senescence, suggesting that differences in gene regulatory network may exist between these two leaf senescence

  3. Variation in light absorption properties of mentha aquatica L. as a function of leaf form: Implications for plant growth

    DEFF Research Database (Denmark)

    Enriquez, Susana; Jensen, Kaj Sand

    2008-01-01

    To understand the association between leaf form and leaf optical properties, we examined light absorption variations in the leaves of Mentha aquatica L., an amphibious freshwater macrophyte. Specific absorption of leaves of M. aquatica showed a 7.5-fold variation, decreasing as pigment per unit...... area increased. This relationship indicates that dispersive samples, such as leaves, although efficient light traps, can also be affected by the "package effect." Mentha aquatica leaves, by expanding their biomass (increased specific leaf area [SLA]), improve their light absorption efficiency per unit...... of both pigment and leaf biomass. Changes in leaf biomass expansion were mainly a result of changes in leaf density, and as a consequence, leaf density appears to be a better descriptor of light absorption efficiency in M. aquatica leaves than does leaf thickness. Light absorption efficiency per unit...

  4. CIRCADIAN CLOCK-ASSOCIATED 1 Inhibits Leaf Senescence in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Yi Song

    2018-03-01

    Full Text Available Leaf senescence is an integral part of plant development, and the timing and progressing rate of senescence could substantially affect the yield and quality of crops. It has been known that a circadian rhythm synchronized with external environmental cues is critical for the optimal coordination of various physiological and metabolic processes. However, the reciprocal interactions between the circadian clock and leaf senescence in plants remain unknown. Here, through measuring the physiological and molecular senescence related markers of several circadian components mutants, we found that CIRCADIAN CLOCK-ASSOCIATED 1 inhibits leaf senescence. Further molecular and genetic studies revealed that CCA1 directly activates GLK2 and suppresses ORE1 expression to counteract leaf senescence. As plants age, the expression and periodic amplitude of CCA1 declines and thus weakens the inhibition of senescence. Our findings reveal an age-dependent circadian clock component of the process of leaf senescence.

  5. Genotypic differences in phosphorus use efficiency and yield of wetland rice of southern Viet Nam

    International Nuclear Information System (INIS)

    Bui Thi Hong Thanh; Le Dac Lieu; Luong Thu Tra; Mai Thanh Son; Nguyen Dang Nghia; Do Trung Binh

    1996-01-01

    This study was conducted during 1992 to 1994 with the objective of assessing genotypic differences in phosphorus use efficiency of wetland rice (Oriza sativa L.) and to select genotypes which grow well on soils low in available P or requiring only small amounts of added phosphorus fertilizer. In the first experiment, 24 genotypes of rice were screened under field conditions at low P (0 P added) and high P (90 kg P 2 O 5 /ha) on a gray soil of South Viet Nam. Significant genotypic differences were found in straw and grain yield, total P uptake, plant height and phosphorus use efficiency. Grain yield was highly correlated with phosphorus use efficiency. The effect of P supply was generally small. On average P supply decreased straw yield and increased grain yield. In the second experiment, four genotypes selected from the first experiment were grown under greenhouse conditions for four weeks supplied with 0, 30 and 90 ppm. Dry weight of shoots did not respond to P fertilization, but dry weight of roots increased with increasing P supply. The two efficient genotypes, G6 and G22, showed a higher root/shoot ratio than the two inefficient genotypes, G11 and G19. This indicates a higher potential for P acquisition of G6 and G22. In the third experiment, the same contrasting genotypes, and G18 with intermediate efficiency, were grown under field conditions at 0, 30, 60, 90 and 120 kg P 2 O 5 /ha. Of the two inefficient genotypes, G11 gave the highest grain yield at 60 and G19 at 90 kg P 2 O 5 /ha; G18 gave a clear response up to 60 kg P 2 O 5 /ha. Based on the information obtained in this study we conclude that G6 and G22 are efficiently and well adapted rice genotypes to gray soils of South Viet Nam, low in available P. At low P supply G6 may be slightly better than G22. Further, the 15 N tracer study showed that for G6, a small P supply (30 kg P 2 O 5 /ha) can increase the % N recover from urea applied at 120 kg N/ha. (author). 12 refs, 6 figs, 3 tabs

  6. Genotypic differences in phosphorus use efficiency and yield of wetland rice of southern Viet Nam

    Energy Technology Data Exchange (ETDEWEB)

    Hong Thanh, Bui Thi; Lieu, Le Dac; Tra, Luong Thu; Son, Mai Thanh [Center of Nuclear Techniques, Ho Chi Minh City (Viet Nam); Nghia, Nguyen Dang; Binh, Do Trung [Agricultural Science Inst., Ho Chi Minh City (Viet Nam)

    1996-07-01

    This study was conducted during 1992 to 1994 with the objective of assessing genotypic differences in phosphorus use efficiency of wetland rice (Oriza sativa L.) and to select genotypes which grow well on soils low in available P or requiring only small amounts of added phosphorus fertilizer. In the first experiment, 24 genotypes of rice were screened under field conditions at low P (0 P added) and high P (90 kg P{sub 2}O{sub 5}/ha) on a gray soil of South Viet Nam. Significant genotypic differences were found in straw and grain yield, total P uptake, plant height and phosphorus use efficiency. Grain yield was highly correlated with phosphorus use efficiency. The effect of P supply was generally small. On average P supply decreased straw yield and increased grain yield. In the second experiment, four genotypes selected from the first experiment were grown under greenhouse conditions for four weeks supplied with 0, 30 and 90 ppm. Dry weight of shoots did not respond to P fertilization, but dry weight of roots increased with increasing P supply. The two efficient genotypes, G6 and G22, showed a higher root/shoot ratio than the two inefficient genotypes, G11 and G19. This indicates a higher potential for P acquisition of G6 and G22. In the third experiment, the same contrasting genotypes, and G18 with intermediate efficiency, were grown under field conditions at 0, 30, 60, 90 and 120 kg P{sub 2}O{sub 5}/ha. Of the two inefficient genotypes, G11 gave the highest grain yield at 60 and G19 at 90 kg P{sub 2}O{sub 5}/ha; G18 gave a clear response up to 60 kg P{sub 2}O{sub 5}/ha. Based on the information obtained in this study we conclude that G6 and G22 are efficiently and well adapted rice genotypes to gray soils of South Viet Nam, low in available P. At low P supply G6 may be slightly better than G22. Further, the {sup 15}N tracer study showed that for G6, a small P supply (30 kg P{sub 2}O{sub 5}/ha) can increase the % N recover from urea applied at 120 kg N/ha.

  7. Tuning Transpiration by Interfacial Solar Absorber-Leaf Engineering.

    Science.gov (United States)

    Zhuang, Shendong; Zhou, Lin; Xu, Weichao; Xu, Ning; Hu, Xiaozhen; Li, Xiuqiang; Lv, Guangxin; Zheng, Qinghui; Zhu, Shining; Wang, Zhenlin; Zhu, Jia

    2018-02-01

    Plant transpiration, a process of water movement through a plant and its evaporation from aerial parts especially leaves, consumes a large component of the total continental precipitation (≈48%) and significantly influences global water distribution and climate. To date, various chemical and/or biological explorations have been made to tune the transpiration but with uncertain environmental risks. In recent years, interfacial solar steam/vapor generation is attracting a lot of attention for achieving high energy transfer efficiency. Various optical and thermal designs at the solar absorber-water interface for potential applications in water purification, seawater desalination, and power generation appear. In this work, the concept of interfacial solar vapor generation is extended to tunable plant transpiration by showing for the first time that the transpiration efficiency can also be enhanced or suppressed through engineering the solar absorber-leaf interface. By tuning the solar absorption of membrane in direct touch with green leaf, surface temperature of green leaf will change accordingly because of photothermal effect, thus the transpiration efficiency as well as temperature and relative humidity in the surrounding environment will be tuned. This tunable transpiration by interfacial absorber-leaf engineering can open an alternative avenue to regulate local atmospheric temperature, humidity, and eventually hydrologic cycle.

  8. Tuning Transpiration by Interfacial Solar Absorber‐Leaf Engineering

    Science.gov (United States)

    Zhuang, Shendong; Zhou, Lin; Xu, Weichao; Xu, Ning; Hu, Xiaozhen; Li, Xiuqiang; Lv, Guangxin; Zheng, Qinghui; Zhu, Shining

    2017-01-01

    Abstract Plant transpiration, a process of water movement through a plant and its evaporation from aerial parts especially leaves, consumes a large component of the total continental precipitation (≈48%) and significantly influences global water distribution and climate. To date, various chemical and/or biological explorations have been made to tune the transpiration but with uncertain environmental risks. In recent years, interfacial solar steam/vapor generation is attracting a lot of attention for achieving high energy transfer efficiency. Various optical and thermal designs at the solar absorber–water interface for potential applications in water purification, seawater desalination, and power generation appear. In this work, the concept of interfacial solar vapor generation is extended to tunable plant transpiration by showing for the first time that the transpiration efficiency can also be enhanced or suppressed through engineering the solar absorber–leaf interface. By tuning the solar absorption of membrane in direct touch with green leaf, surface temperature of green leaf will change accordingly because of photothermal effect, thus the transpiration efficiency as well as temperature and relative humidity in the surrounding environment will be tuned. This tunable transpiration by interfacial absorber‐leaf engineering can open an alternative avenue to regulate local atmospheric temperature, humidity, and eventually hydrologic cycle. PMID:29619300

  9. Identification of Leaf Promoters for Use in Transgenic Wheat

    Directory of Open Access Journals (Sweden)

    Saqer S. Alotaibi

    2018-03-01

    Full Text Available Wheat yields have plateaued in recent years and given the growing global population there is a pressing need to develop higher yielding varieties to meet future demand. Genetic manipulation of photosynthesis in elite wheat varieties offers the opportunity to significantly increase yields. However, the absence of a well-defined molecular tool-box of promoters to manipulate leaf processes in wheat hinders advancements in this area. Two promoters, one driving the expression of sedoheptulose-1,7-bisphosphatase (SBPase and the other fructose-1,6-bisphosphate aldolase (FBPA from Brachypodium distachyon were identified and cloned into a vector in front of the GUS reporter gene. Both promoters were shown to be functionally active in wheat in both transient assays and in stably transformed wheat plants. Analysis of the stable transformants of wheat (cv. Cadenza showed that both promoters controlled gus expression throughout leaf development as well as in other green tissues. The availability of these promoters provides new tools for the expression of genes in transgenic wheat leaves and also paves the way for multigene manipulation of photosynthesis to improve yields.

  10. Effect of Different Substrates and Casing Materials on the Growth and Yield of Calocybe indica.

    Science.gov (United States)

    Amin, Ruhul; Khair, Abul; Alam, Nuhu; Lee, Tae Soo

    2010-06-01

    Calocybe indica, a tropical edible mushroom, is popular because it has good nutritive value and it can be cultivated commercially. The current investigation was undertaken to determine a suitable substrate and the appropriate thickness of casing materials for the cultivation of C. indica. Optimum mycelial growth was observed in coconut coir substrate. Primordia initiation with the different substrates and casing materials was observed between the 13th and 19th day. The maximum length of stalk was recorded from sugarcane leaf, while diameter of stalk and pileus, and thickness of pileus were found in rice straw substrate. The highest biological and economic yield, and biological efficiency were also obtained in the rice straw substrate. Cow dung and loamy soil, farm-yard manure, loamy soil and sand, and spent oyster mushroom substrates were used as casing materials to evaluate the yield and yield-contributing characteristics of C. indica. The results indicate that the number of effective fruiting bodies, the biological and economic yield, and the biological efficiency were statistically similar all of the casing materials used. The maximum biological efficiency was found in the cow dung and loamy soil casing material. The cow dung and loamy soil (3 cm thick) was the best casing material and the rice straw was the best substrate for the commercial cultivation of C. indica.

  11. Leaf nutrient resorption, leaf lifespan and the retention of nutrients in seagrass systems

    NARCIS (Netherlands)

    Hemminga, M.A.; Marbà, N.; Stapel, J.

    1999-01-01

    Efficient nutrient resorption from senescing leaves, and extended leaf life spans are important strategies in order to conserve nutrients for plants in general. Despite the fact that seagrasses often grow in oligotrophic waters, these conservation strategies are not strongly developed in seagrasses.

  12. Solar radiation use efficiency and morphophysiological indices in common bean cultivars

    Directory of Open Access Journals (Sweden)

    Gisele Carneiro da Silva Teixeira

    2015-03-01

    Full Text Available Common bean crops present a broad edaphoclimatic adaptation, allowing their cultivation throughout the year. However, in order to reach good economic income levels, it is fundamental to understand the processes that affect the growth and development of the crop in various environments. This study aimed to compare two common bean cultivars (BRS Radiante and Pérola contrasting in cycle and growth behavior by using morphophysiological indices and solar radiation use efficiency. The following traits were evaluated: light extinction coefficient, radiation use efficiency, phenologic development, leaf area index, total dry matter weight, crop growth rate, relative growth rate and dry matter partitioning. The BRS Radiante cultivar shows a higher vigor, when compared to the Pérola cultivar, due to its faster initial phenologic development and higher initial and relative growth rates. Both cultivars differ for leaf area index and shoot architecture, although that does not happen for light extinction coefficient. The BRS Radiante cultivar shows a higher solar radiation use efficiency, resulting in a greater dry matter yield throughout its development.

  13. Leaf storage conditions and genomic DNA isolation efficiency in ...

    African Journals Online (AJOL)

    SERVER

    2008-03-04

    Mar 4, 2008 ... Full Length Research Paper. Leaf storage ... 2006; Chen and Yang, 2004; Nan et al., 2003; Ipek and. Madison, 2001 ... the same function of pure DNA isolation. These are .... eppendorf tube and then dropped in liquid nitrogen for 2 min. The weighed ..... the solubility of polysaccharides in ethanol, effectively.

  14. On the global relationships between photosynthetic water-use efficiency, leaf mass per unit area and atmospheric demand in woody and herbaceous plants

    Science.gov (United States)

    Letts, M. G.; Fox, T. A.; Gulias, J.; Galmes, J.; Hikosaka, K.; Wright, I.; Flexas, J.; Awada, T.; Rodriguez-Calcerrada, J.; Tobita, H.

    2013-12-01

    A global dataset was compiled including woody and herbaceous C3 species from forest, Mediterranean and grassland-shrubland ecosystems, to elucidate the dependency of photosynthetic water-use efficiency on vapour pressure deficit (D) and leaf traits. Mean leaf mass per unit area (LMA) was lower and mass-based leaf nitrogen content (Nmass) was higher in herbaceous species. Higher mean stomatal conductance (gs), transpiration rate (E) and net CO2 assimilation rate under light saturating conditions (Amax) were observed in herbs, but photosynthetic and intrinsic water-use efficiencies (WUE = Amax/E and WUEi = Amax/gs) were lower than in woody plants. Woody species maintained stricter stomatal regulation of water loss at low D, resulting in a steeper positive and linear relationship between log D and log E. Herbaceous species possessed very high gs at low D, resulting in higher ratio of substomatal to atmospheric CO2 concentrations (ci/ca) and E, but lower WUE and WUEi than woody plants, despite higher Amax. The lower WUE and higher rates of gas exchange were most pronounced in herbs with low LMA and high Nmass. Photosynthetic water use also differed between species from grassland-shrubland and Mediterranean or forest environments. Water-use efficiency showed no relationship with either D or LMA in grassland-shrubland species, but showed a negative relationship with D in forest and chaparral. The distinct photosynthetic water-use of woody and herbaceous plants is consistent with the opportunistic growth strategy of herbs and the more conservative growth strategy of woody species. Further research is recommended to examine the implications of these functional group and ecosystem differences in the contexts of climate and atmospheric change.

  15. Leaf mineral nutrient remobilization during leaf senescence and modulation by nutrient deficiency.

    Directory of Open Access Journals (Sweden)

    Anne eMaillard

    2015-05-01

    Full Text Available Higher plants have to cope with fluctuating mineral resource availability. However strategies such as stimulation of root growth, increased transporter activities, and nutrient storage and remobilization have been mostly studied for only a few macronutrients. Leaves of cultivated crops (Zea mays, Brassica napus, Pisum sativum, Triticum aestivum, Hordeum vulgare and tree species (Quercus robur, Populus nigra, Alnus glutinosa grown under field conditions were harvested regularly during their life span and analysed to evaluate the net mobilization of 13 nutrients during leaf senescence. While N was remobilized in all plant species with different efficiencies ranging from 40% (maize to 90% (wheat, other macronutrients (K-P-S-Mg were mobilized in most species. Ca and Mn, usually considered as having low phloem mobility were remobilized from leaves in wheat and barley. Leaf content of Cu-Mo-Ni-B-Fe-Zn decreased in some species, as a result of remobilization. Overall, wheat, barley and oak appeared to be the most efficient at remobilization while poplar and maize were the least efficient. Further experiments were performed with rapeseed plants subjected to individual nutrient deficiencies. Compared to field conditions, remobilization from leaves was similar (N-S-Cu or increased by nutrient deficiency (K-P-Mg while nutrient deficiency had no effect on Mo-Zn-B-Ca-Mn, which seemed to be non-mobile during leaf senescence under field conditions. However, Ca and Mn were largely mobilized from roots (-97 and -86% of their initial root contents, respectively to shoots. Differences in remobilization between species and between nutrients are then discussed in relation to a range of putative mechanisms.

  16. Effects of Row Spacing and Plant Density on Yield and Yield Components of Sweet Corn in Climatic Conditions of Isfahan

    Directory of Open Access Journals (Sweden)

    N. Khodaeian

    2013-06-01

    Full Text Available To evaluate the effects of row spacing and plant density on yield and yield components of sweet corn, variety KSC403, an experiment was conducted in Research Farm of Isfahan University of Technology, Isfahan, Iran, in 2007, as randomized complete block design with a split-plot layout and three replications. The main plots were allocated to two row spacing (60 and 75 cm and the sub-plots accommodated four levels of plant density (50000, 70000, 90000 and 110000 plants per ha. There was significant increase in leaf area index, shoot dry weight, 100-grain fresh weight and grain fresh yield, as row width was decreased from 75 to 60 cm but the plant height was decreased. There was no significant effect of row spacing on number of rows per ear, number of grains per row and number of grains per ear. Plant height, leaf area index, shoot dry weight per m2 and number of ears per m2 were increased with an increase in plant density. The number of rows per ear, number of grains per row, number of grains per ear, 100-grain fresh weight and grain fresh yield were significantly higher under plant densities of 90000 and 110000 as compared to 50000 and 70000 plants per ha. There was significant interaction between row spacing and plant density for leaf area index, shoot dry weight, number of grains per ear, 100-grain fresh weight and grain fresh yield. Under all plant densities, the grain fresh yield was higher in 60-cm row width compared to 70-cm row width. However, the difference between these two row spacing was not significant in plant densities of 50000 and 110000 plants per ha. The highest grain fresh yield (33940 kg/ha was achieved under row spacing 60 cm and 70000 plants per ha and the least grain fresh yield (20750 kg/ha was obtained in under 75 cm row width and 110000 plants per ha. Considering the obtained results of this experiment, to have maximum grain fresh yield of sweet corn under Isfahan climate, the row spacing of 60 cm and plant density of

  17. Introgression of leaf rust and stripe rust resistance from Sharon goatgrass (Aegilops sharonensis Eig) into bread wheat (Triticum aestivum L.).

    Science.gov (United States)

    Millet, E; Manisterski, J; Ben-Yehuda, P; Distelfeld, A; Deek, J; Wan, A; Chen, X; Steffenson, B J

    2014-06-01

    Leaf rust and stripe rust are devastating wheat diseases, causing significant yield losses in many regions of the world. The use of resistant varieties is the most efficient way to protect wheat crops from these diseases. Sharon goatgrass (Aegilops sharonensis or AES), which is a diploid wild relative of wheat, exhibits a high frequency of leaf and stripe rust resistance. We used the resistant AES accession TH548 and induced homoeologous recombination by the ph1b allele to obtain resistant wheat recombinant lines carrying AES chromosome segments in the genetic background of the spring wheat cultivar Galil. The gametocidal effect from AES was overcome by using an "anti-gametocidal" wheat mutant. These recombinant lines were found resistant to highly virulent races of the leaf and stripe rust pathogens in Israel and the United States. Molecular DArT analysis of the different recombinant lines revealed different lengths of AES segments on wheat chromosome 6B, which indicates the location of both resistance genes.

  18. An Efficient Return Algorithm For Non-Associated Plasticity With Linear Yield Criteria In Principal Stress Space

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars; Andersen, Lars

    2007-01-01

    . The stress return and the formation of the constitutive matrix is carried out in principal stress space. Here the manipulations simplify and rely on geometrical arguments. The singularities arising at the intersection of yield planes are dealt with in a straightforward way also based on geometrical......An efficient return algorithm for stress update in numerical plasticity computations is presented. The yield criterion must be linear in principal stress space and can be composed of any number of yield planes. Each of these yield planes may have an associated or non-associated flow rule...

  19. An efficient in vitro shoot regeneration from leaf petiolar explants and ex vitro rooting of Bixa orellana L.- A dye yielding plant.

    Science.gov (United States)

    Mohammed, Arifullah; Chiruvella, Kishore K; Namsa, Nima D; Ghanta, Rama Gopal

    2015-07-01

    Bixa orellana L. (Bixaceae) is a multipurpose tree grown for the production of commercially important dyes. In the present study, an efficient, reproducible protocol was developed for direct plant regeneration from in vitro derived petiole explants of Bixa orellana L. Murashige and Skoog medium (MS) supplemented with 2-isopentenyl adenine (9.8 μM) and naphthalene acetic acid (10.7 μM) was found to be optimum for production of high frequency of shoot organogenesis. Subculturing of the shoots onto the fresh MS medium containing similar concentrations of 2-iP (9.8 μM) and NAA (10.7 μM) produced elongated shoots. Elongated shoots when placed onto MS medium supplemented with 1.7 μM indole-3-acetic acid and 14.7 μM 2-iP produced optimal rooting. Rooted plantlets were acclimatized and transplanted to the field successfully. Histological investigation revealed the origin of shoot primordia, from sub-epidermal cells of petiole explants. The regeneration protocol developed in this study can be useful for mass in vitro propagation and effective genetic transformation of commercially important edible dye yielding tree species.

  20. Manufacturing of par-fried french-fries. Part 2: Modelling yield efficiency of peeling

    NARCIS (Netherlands)

    Somsen, D.J.; Capelle, A.; Tramper, J.

    2004-01-01

    The paper outlines the yield efficiency of steam peeling. It was proven that peeling potatoes manually with sandpaper results in the lowest possible peel losses. These losses were desired or wanted losses. However, in practice steam peeling results not only in wanted losses but also in substantial

  1. Gamma radiation induced mutant for improved yield components in sunflower

    International Nuclear Information System (INIS)

    Elangovan, M.

    2001-01-01

    Sunflower has become an important oilseed in the Indian vegetable oil pool following its introduction from Russia in 1969. It can be used for all quality products useful to humans. The need for genetic variability and new useful gene sources has necessitated that sunflower breeders and geneticists utilize a wide range of germplasm in their breeding programmes. The induction of mutations in sunflower by physical and chemical mutagens has been practiced quite intensively in the last two decades. The results recorded to date suggest that utilization of mutagenesis could be a great advantage in improving the sunflower crop. An induced mutation programme was undertaken to generate variability in the variety 'Morden' using gamma rays. The certified and genetically pure seeds were irradiated with 50, 100, and 150 Gy gamma rays and used for further studies. Selection in M 2 generations, raised from different treatments, revealed the presence of an erectophylly leaf mutant from 50 Gy treatment. The isolated mutant showed improved yield components like head diameter, 100- seed weight and yield per plant. The mutant was a plant with short petiole length and erect leaves. This type of leaf get sunlight throughout the day. From morning to afternoon, the first half of the leaf gets sunlight, and from afternoon to evening the second half of the leaf gets sunlight. As a result of getting sunlight the whole day, the plant had more photosynthetic products and grew vigorously. Plant height, head diameter and 100-seed weight had direct effect on seed yield, and the number of leaves and stem diameter influenced the seed yield indirectly. In the M 3 generation, the mutant showed an almost two-fold increase over the parent variety for all investigated characters, except that of the yield per plant where there was a three-fold increase. The present investigation has shown that there are remarkable possibilities of increasing the yield components in sunflower by induced mutations

  2. Effect of jasmonic acid elicitation on the yield, chemical composition, and antioxidant and anti-inflammatory properties of essential oil of lettuce leaf basil (Ocimum basilicum L.).

    Science.gov (United States)

    Złotek, Urszula; Michalak-Majewska, Monika; Szymanowska, Urszula

    2016-12-15

    The effect of elicitation with jasmonic acid (JA) on the plant yield, the production and composition of essential oils of lettuce leaf basil was evaluated. JA-elicitation slightly affected the yield of plants and significantly increased the amount of essential oils produced by basil - the highest oil yield (0.78±0.005mL/100gdw) was achieved in plants elicited with 100μM JA. The application of the tested elicitor also influenced the chemical composition of basil essential oils - 100μM JA increased the linalool, eugenol, and limonene levels, while 1μM JA caused the highest increase in the methyl eugenol content. Essential oils from JA-elicited basil (especially 1μM and 100μM) exhibited more effective antioxidant and anti-inflammatory potential; therefore, this inducer may be a very useful biochemical tool for improving production and composition of herbal essential oils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Effects of sample drying and storage, and choice of extraction solvent and analysis method on the yield of birch leaf hydrolyzable tannins.

    Science.gov (United States)

    Salminen, Juha-Pekka

    2003-06-01

    In this study, I investigated the effects of different methods of sample drying and storage, and the choice of extraction solvent and analysis method on the concentrations of 14 individual hydrolyzable tannins (HTs), and insoluble ellagitannins in birch (Betula pubescens) leaves. Freeze- and vacuum-drying of birch leaves were found to provide more reliable results than air- or oven-drying. Storage of leaves at -20 degrees C for 3 months before freeze-drying did not cause major changes in tannin content, although levels of 1,2,3,4,6-penta-O-galloylglucose and isostrictinin were altered. Storage of dried leaf material at -20 degrees C is preferred because 1 year storage of freeze-dried leaves at 4 degrees C and at room temperature decreased the concentration of the pedunculagin derivative, one of the main ellagitannins of birch. Furthermore, storage at room temperature increased the levels of isostrictinin and 2,3-(S)-HHDP-glucose, indicating possible HT catabolism. Of the extraction solvents tested, aqueous acetone was superior to pure acetone, or aqueous or pure methanol. The addition of 0.1% ascorbic acid into 70% acetone significantly increased the yield of ellagitannins. presumably by preventing their oxidation. By comparing the conventional rhodanine assay and the HPLC-ESI-MS assay for quantification of leaf galloylglucoses, the former tends to underestimate total concentrations of galloylglucoses in birch leaf extract. On the basis of the outcomes of all the method and solvent comparisons, their suitability for qualitative and quantitative analysis of plant HTs is discussed, emphasizing that each plant species, with its presumably unique HT composition, is likely to have a unique combination of ideal conditions for tissue preservation and extraction.

  4. Acquiring and preprocessing leaf images for automated plant identification: understanding the tradeoff between effort and information gain

    Directory of Open Access Journals (Sweden)

    Michael Rzanny

    2017-11-01

    Full Text Available Abstract Background Automated species identification is a long term research subject. Contrary to flowers and fruits, leaves are available throughout most of the year. Offering margin and texture to characterize a species, they are the most studied organ for automated identification. Substantially matured machine learning techniques generate the need for more training data (aka leaf images. Researchers as well as enthusiasts miss guidance on how to acquire suitable training images in an efficient way. Methods In this paper, we systematically study nine image types and three preprocessing strategies. Image types vary in terms of in-situ image recording conditions: perspective, illumination, and background, while the preprocessing strategies compare non-preprocessed, cropped, and segmented images to each other. Per image type-preprocessing combination, we also quantify the manual effort required for their implementation. We extract image features using a convolutional neural network, classify species using the resulting feature vectors and discuss classification accuracy in relation to the required effort per combination. Results The most effective, non-destructive way to record herbaceous leaves is to take an image of the leaf’s top side. We yield the highest classification accuracy using destructive back light images, i.e., holding the plucked leaf against the sky for image acquisition. Cropping the image to the leaf’s boundary substantially improves accuracy, while precise segmentation yields similar accuracy at a substantially higher effort. The permanent use or disuse of a flash light has negligible effects. Imaging the typically stronger textured backside of a leaf does not result in higher accuracy, but notably increases the acquisition cost. Conclusions In conclusion, the way in which leaf images are acquired and preprocessed does have a substantial effect on the accuracy of the classifier trained on them. For the first time, this

  5. Microwave Pretreatments of Switchgrass Leaf and Stem Fractions to Increase Methane Production

    Directory of Open Access Journals (Sweden)

    Chunhui Wu

    2015-05-01

    Full Text Available The objective of this study was to determine the effectiveness of microwave pretreatments on methane production from two switchgrass tissues (leaf vs. stem. The methane production from the leaf fraction was significantly affected by the microwave final temperature, while production from the stem fraction was affected by the combination of the microwave final temperature and heating rate. Thus, the highest methane yield from the leaf (134.81 mL CH4/g of volatile solids (VS was obtained at 100 °C, while the highest yield from the stem (99.35 mL CH4/g VS was obtained at 150 °C, with a heating rate of 10 °C/min. Although methane production from the leaf fraction was merely enhanced by 9.1% after microwave pretreatments, the time required to reach 80% of ultimate methane production was reduced by 12 days. For the stem fraction, methane production was improved by 5.2% after microwave pretreatment, and the time to obtain 80% of ultimate methane production increased.

  6. Heritability and correlates of maize yield ( Zea mays L .) under ...

    African Journals Online (AJOL)

    Heritability and correlates of maize yield ( Zea mays L .) under varying drought conditions. ... Nigeria Agricultural Journal ... Correlation analysis revealed that days to 50% tasseling and silking under non-stress, ASI and leaf senescence under severe stress exhibited negative and significant correlations with grain yield.

  7. Ammonia volatilization and yield components after application of polymer-coated urea to maize

    Directory of Open Access Journals (Sweden)

    Eduardo Zavaschi

    2014-08-01

    Full Text Available A form of increasing the efficiency of N fertilizer is by coating urea with polymers to reduce ammonia volatilization. The aim of this study was to evaluate the effect of polymer-coated urea on the control of ammonia volatilization, yield and nutritional characteristics of maize. The experiment was carried out during one maize growing cycle in 2009/10 on a Geric Ferralsol, inUberlândia, MG, Brazil. Nitrogen fertilizers were applied as topdressing on the soil surface in the following urea treatments: polymer-coated urea at rates of 45, 67.5 and 90 kg ha-1 N and one control treatment (no N, in randomized blocks with four replications. Nitrogen application had a favorable effect on N concentrations in leaves and grains, Soil Plant Analysis Development (SPAD chlorophyll meter readings and on grain yield, where as coated urea had no effect on the volatilization rates, SPAD readings and N leaf and grain concentration, nor on grain yield in comparison to conventional fertilization.

  8. Silver nano fabrication using leaf disc of Passiflora foetida Linn

    Science.gov (United States)

    Lade, Bipin D.; Patil, Anita S.

    2017-06-01

    The main purpose of the experiment is to develop a greener low cost SNP fabrication steps using factories of secondary metabolites from Passiflora leaf extract. Here, the leaf extraction process is omitted, and instead a leaf disc was used for stable SNP fabricated by optimizing parameters such as a circular leaf disc of 2 cm (1, 2, 3, 4, 5) instead of leaf extract and grade of pH (7, 8, 9, 11). The SNP synthesis reaction is tried under room temperature, sun, UV and dark condition. The leaf disc preparation steps are also discussed in details. The SNP obtained using (1 mM: 100 ml AgNO3+ singular leaf disc: pH 9, 11) is applied against featured room temperature and sun condition. The UV spectroscopic analysis confirms that sun rays synthesized SNP yields stable nano particles. The FTIR analysis confirms a large number of functional groups such as alkanes, alkyne, amines, aliphatic amine, carboxylic acid; nitro-compound, alcohol, saturated aldehyde and phenols involved in reduction of silver salt to zero valent ions. The leaf disc mediated synthesis of silver nanoparticles, minimizes leaf extract preparation step and eligible for stable SNP synthesis. The methods sun and room temperature based nano particles synthesized within 10 min would be use certainly for antimicrobial activity.

  9. Herbivores sculpt leaf traits differently in grasslands depending on life form and land-use histories.

    Science.gov (United States)

    Firn, Jennifer; Schütz, Martin; Nguyen, Huong; Risch, Anita C

    2017-01-01

    Vertebrate and invertebrate herbivores alter plant communities directly by selectively consuming plant species; and indirectly by inducing morphological and physiological changes to plant traits that provide competitive or survivorship advantages to some life forms over others. Progressively excluding aboveground herbivore communities (ungulates, medium and small sized mammals, invertebrates) over five growing seasons, we explored how leaf morphology (specific leaf area or SLA) and nutrition (nitrogen, carbon, phosphorous, potassium, sodium, and calcium) of different plant life forms (forbs, legumes, grasses, sedges) correlated with their dominance. We experimented in two subalpine grassland types with different land-use histories: (1) heavily grazed, nutrient-rich, short-grass vegetation and (2) lightly grazed, lower nutrient tall-grass vegetation. We found differences in leaf traits between treatments where either all herbivores were excluded or all herbivores were present, showing the importance of considering the impacts of both vertebrates and invertebrates on the leaf traits of plant species. Life forms responses to the progressive exclusion of herbivores were captured by six possible combinations: (1) increased leaf size and resource use efficiency (leaf area/nutrients) where lower nutrient levels are invested in leaf construction, but a reduction in the number of leaves, for example, forbs in both vegetation types, (2) increased leaf size and resource use efficiency, for example, legumes in short grass, (3) increased leaf size but a reduction in the number of leaves, for example, legumes in the tall grass, (4) increased number of leaves produced and increased resource use efficiency, for example, grasses in the short grass, (5) increased resource use efficiency of leaves only, for example, grasses and sedges in the tall grass, and (6) no response in terms of leaf construction or dominance, for example, sedges in the short grass. Although we found multiple

  10. The effects of irrigation timing on growth, yield, and physiological traits of hydroponic lettuce

    Directory of Open Access Journals (Sweden)

    Md. Jahedur Rahman

    2018-01-01

    Full Text Available Crop-specific timing of irrigation is necessary to conserve irrigation water and improve yield of vegetables. Therefore, the experiment was conducted to identify the optimum irrigation timings for hydroponic lettuce plants. Three nutrient solution timings, T1(once a day at 0900 hours, T2(once on alternative days at 0900 hours, and T3(once at two-day intervals, and three varieties, ‘Legacy’ (V1, ‘Red fire’ (V2, and ‘Green wave’ (V3 were evaluated. Growth and yield parameters, including number of leaves, leaf length, leaf diameter, and fresh weight of leaves, and growth parameters, including leaf area (LA, leaf area ratio (LAR, leaf mass ratio (LMR, root weight ratio (RWR, relative growth rate (RGR, and net assimilation rate (NAR were determined. The values of growth parameters were the highest for T1. The highest and lowest NAR and RGR values were obtained for T1 and T3, respectively. The values of most growth traits, including fresh weight, NAR, and RGR were higher for V1 than other varieties. T1 provides high yield with comparatively less irrigation water and nutrient solution so it can be used to culture lettuce using aggregate hydroponics as.

  11. Genetic characterisation of seed yield and fertility traits in perennial ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Studer, Bruno; Jensen, Louise Bach; Hentrup, Stephan

    2008-01-01

    A population. Path analysis partitioned the direct and indirect effects of seed yield components on seed yield per plant. Seed yield per panicle showed the highest effect on total seed yield. The adjusted mean values of each trait and a genetic linkage map consisting of 97 anonymous and 85 gene associated DNA......Seed yield is a trait of major interest for the key grassland species Lolium perenne L. An F2 mapping population of perennial ryegrass (VrnA), recently characterised for vernalisation response, was assessed in a glasshouse for traits related to seed yield based on a lattice design with four...... replications over 2 years. The traits heading date, plant height, length of panicles, number of panicles per plant, seed yield per panicle, flag leaf length, flag leaf width and seed yield per plant revealed repeatabilities ranging from 41 to 76% and a considerable amount of genetic variation in the Vrn...

  12. The Nissan LEAF electric powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Nakazawa, Shinsuke [Nissan Motor Co., Ltd. (Japan)

    2011-07-01

    The need for CO{sub 2} reduction as a countermeasure to global warming, and to move away from our dependence on fossil fuels as a countermeasure to energy security are urgent issues. One of the ultimate goals to achieving these targets is to develop a 'Zero emission car' such as an electric vehicle or a fuel cell vehicle, along with the manufacturing of clean energy. Nissan have developed a new powertrain for the electric vehicle, and have installed it in the Nissan LEAF. Sales of the Nissan LEAF started in North America, Europe and Japan in 2010, with plans to sell it globally by 2012. In order to achieve an improved driving range, power performance and drivability performance, Nissan have adapted a high efficiency synchronous motor, a water-cooled inverter, and reducer. Moreover, the Nissan LEAF has the capability of a 3.3kW AC charge and a 50kW DC quick charge. This presentation will introduce the features of the electric powertrain adopted for Nissan LEAF. (orig.)

  13. Optical crop sensor for variable-rate nitrogen fertilization in corn: II - indices of fertilizer efficiency and corn yield

    Directory of Open Access Journals (Sweden)

    Jardes Bragagnolo

    2013-10-01

    Full Text Available Generally, in tropical and subtropical agroecosystems, the efficiency of nitrogen (N fertilization is low, inducing a temporal variability of crop yield, economic losses, and environmental impacts. Variable-rate N fertilization (VRF, based on optical spectrometry crop sensors, could increase the N use efficiency (NUE. The objective of this study was to evaluate the corn grain yield and N fertilization efficiency under VRF determined by an optical sensor in comparison to the traditional single-application N fertilization (TSF. With this purpose, three experiments with no-tillage corn were carried out in the 2008/09 and 2010/11 growing seasons on a Hapludox in South Brazil, in a completely randomized design, at three different sites that were analyzed separately. The following crop properties were evaluated: aboveground dry matter production and quantity of N uptake at corn flowering, grain yield, and vegetation index determined by an N-Sensor® ALS optical sensor. Across the sites, the corn N fertilizer had a positive effect on corn N uptake, resulting in increased corn dry matter and grain yield. However, N fertilization induced lower increases of corn grain yield at site 2, where there was a severe drought during the growing period. The VRF defined by the optical crop sensor increased the apparent N recovery (NRE and agronomic efficiency of N (NAE compared to the traditional fertilizer strategy. In the average of sites 1 and 3, which were not affected by drought, VRF promoted an increase of 28.0 and 41.3 % in NAE and NRE, respectively. Despite these results, no increases in corn grain yield were observed by the use of VRF compared to TSF.

  14. Overexpression of the TaSHN1 transcription factor in bread wheat leads to leaf surface modifications, improved drought tolerance and no yield penalty under controlled growth conditions.

    Science.gov (United States)

    Bi, Huihui; Shi, Jianxin; Kovalchuk, Natalia; Luang, Sukanya; Bazanova, Natalia; Chirkova, Larissa; Zhang, Dabing; Shavrukov, Yuri; Stepanenko, Anton; Tricker, Penny; Langridge, Peter; Hrmova, Maria; Lopato, Sergiy; Borisjuk, Nikolai

    2018-05-14

    Transcription factors regulate multiple networks, mediating the responses of organisms to stresses, including drought. Here we investigated the role of the wheat transcription factor TaSHN1 in crop growth and drought tolerance. TaSHN1, isolated from bread wheat, was characterised for molecular interactions and functionality. The overexpression of TaSHN1 in wheat was followed by the evaluation of T 2 and T 3 transgenic lines for drought tolerance, growth and yield components. Leaf surface changes were analysed by light microscopy, SEM, TEM and GC-MS/GC-FID. TaSHN1 behaves as a transcriptional activator in a yeast transactivation assay and binds stress-related DNA cis-elements, determinants of which were revealed using 3D molecular modelling. The overexpression of TaSHN1 in transgenic wheat did not result in a yield penalty under the controlled plant growth conditions of a glasshouse. Transgenic lines had significantly lower stomatal density and leaf water loss, and exhibited improved recovery after severe drought, compared to control plants. The comparative analysis of cuticular waxes revealed an increased accumulation of alkanes in leaves of transgenic lines. Our data demonstrate that TaSHN1 may operate as a positive modulator of drought stress tolerance. Positive attributes could be mediated through an enhanced accumulation of alkanes and reduced stomatal density. This article is protected by copyright. All rights reserved.

  15. Yield Traits and Water and Nitrogen Use Efficiencies of Bell Pepper Grown in Plastic-Greenhouse

    Directory of Open Access Journals (Sweden)

    Vincenzo Candido

    2009-09-01

    Full Text Available We report the results of a two-year study assessing the effects of nitrogen fertilization and irrigation regimes on yield traits and on water and nitrogen use efficiency of greenhouse-grown bell pepper (Capsicum annuum L.. The trials involved the combination of four N doses (0, 100, 200, 300 kg ha-1 with two irrigation regimes (100% restitution of ETc; repeated cycles of water stress starting from fruit set. In the second year, the crop was transplanted one month earlier than in the first year and was mulched with plastic sheeting. The highest yield in both years was obtained by associating 100% restitution of ETc and the N dose of 200 kg ha-1. The marketable yields were 37 and 72 t ha-1 in 1998 and 1999, respectively. Doubling of the yield in the second year was probably due to the earlier transplantation and mulching, confirming the numerous benefits of the latter technique. The water deficit imposed during the late flowering-early fruit set phase had negative effects on the crop, with declines of the marketable yield of up to 44% due to the reduced number and weight of the fruit and the increased waste, mainly peppers with blossom-end rot, cracking, sun-burn and malformations. The peppers grown under water stress were richer in dry matter and soluble solids. The yield declines due to water deficit varied in relation to the N dose, as confirmed by the numerous interactions recorded between irrigation regime and nitrogen level.Without nitrogen fertilization, the quantity and quality of the fruits remained unchanged, while the maximum dose (300 kg ha-1 enhanced the negative effects of the water deficit on the number (-52% and weight (-161% of marketable peppers. Moreover, the waste peppers reached 31% of the total production (by weight, with over 21% affected by blossom-end rot. Water stress led to a drastic reduction of the total above-ground dry biomass (40% and a significant decrease of nitrogen absorption by the plant (54% with preferential

  16. Prospecting for Energy-Rich Renewable Raw Materials: Agave Leaf Case Study.

    Science.gov (United States)

    Corbin, Kendall R; Byrt, Caitlin S; Bauer, Stefan; DeBolt, Seth; Chambers, Don; Holtum, Joseph A M; Karem, Ghazwan; Henderson, Marilyn; Lahnstein, Jelle; Beahan, Cherie T; Bacic, Antony; Fincher, Geoffrey B; Betts, Natalie S; Burton, Rachel A

    2015-01-01

    Plant biomass from different species is heterogeneous, and this diversity in composition can be mined to identify materials of value to fuel and chemical industries. Agave produces high yields of energy-rich biomass, and the sugar-rich stem tissue has traditionally been used to make alcoholic beverages. Here, the compositions of Agave americana and Agave tequilana leaves are determined, particularly in the context of bioethanol production. Agave leaf cell wall polysaccharide content was characterized by linkage analysis, non-cellulosic polysaccharides such as pectins were observed by immuno-microscopy, and leaf juice composition was determined by liquid chromatography. Agave leaves are fruit-like--rich in moisture, soluble sugars and pectin. The dry leaf fiber was composed of crystalline cellulose (47-50% w/w) and non-cellulosic polysaccharides (16-22% w/w), and whole leaves were low in lignin (9-13% w/w). Of the dry mass of whole Agave leaves, 85-95% consisted of soluble sugars, cellulose, non-cellulosic polysaccharides, lignin, acetate, protein and minerals. Juice pressed from the Agave leaves accounted for 69% of the fresh weight and was rich in glucose and fructose. Hydrolysis of the fructan oligosaccharides doubled the amount of fermentable fructose in A. tequilana leaf juice samples and the concentration of fermentable hexose sugars was 41-48 g/L. In agricultural production systems such as the tequila making, Agave leaves are discarded as waste. Theoretically, up to 4000 L/ha/yr of bioethanol could be produced from juice extracted from waste Agave leaves. Using standard Saccharomyces cerevisiae strains to ferment Agave juice, we observed ethanol yields that were 66% of the theoretical yields. These data indicate that Agave could rival currently used bioethanol feedstocks, particularly if the fermentation organisms and conditions were adapted to suit Agave leaf composition.

  17. Prospecting for Energy-Rich Renewable Raw Materials: Agave Leaf Case Study.

    Directory of Open Access Journals (Sweden)

    Kendall R Corbin

    Full Text Available Plant biomass from different species is heterogeneous, and this diversity in composition can be mined to identify materials of value to fuel and chemical industries. Agave produces high yields of energy-rich biomass, and the sugar-rich stem tissue has traditionally been used to make alcoholic beverages. Here, the compositions of Agave americana and Agave tequilana leaves are determined, particularly in the context of bioethanol production. Agave leaf cell wall polysaccharide content was characterized by linkage analysis, non-cellulosic polysaccharides such as pectins were observed by immuno-microscopy, and leaf juice composition was determined by liquid chromatography. Agave leaves are fruit-like--rich in moisture, soluble sugars and pectin. The dry leaf fiber was composed of crystalline cellulose (47-50% w/w and non-cellulosic polysaccharides (16-22% w/w, and whole leaves were low in lignin (9-13% w/w. Of the dry mass of whole Agave leaves, 85-95% consisted of soluble sugars, cellulose, non-cellulosic polysaccharides, lignin, acetate, protein and minerals. Juice pressed from the Agave leaves accounted for 69% of the fresh weight and was rich in glucose and fructose. Hydrolysis of the fructan oligosaccharides doubled the amount of fermentable fructose in A. tequilana leaf juice samples and the concentration of fermentable hexose sugars was 41-48 g/L. In agricultural production systems such as the tequila making, Agave leaves are discarded as waste. Theoretically, up to 4000 L/ha/yr of bioethanol could be produced from juice extracted from waste Agave leaves. Using standard Saccharomyces cerevisiae strains to ferment Agave juice, we observed ethanol yields that were 66% of the theoretical yields. These data indicate that Agave could rival currently used bioethanol feedstocks, particularly if the fermentation organisms and conditions were adapted to suit Agave leaf composition.

  18. Correlations of visual scores, carcass traits, feed efficiency and retail product yield in Nellore cattle

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Cancian

    2014-02-01

    Full Text Available The growing use of visual scores (VS and ultrasound (US for carcass evaluation in breeding programs, calls for a knowledge of the relationships between these traits and other relevant characteristics, such as feed efficiency and production of commercial cuts. The objective of this study was to evaluate correlations between body visual scores and carcass traits identified by ultrasound (US and feed efficiency (FE, carcass weight (HCW, dressing percentage (DP and retail product yield (RPY in beef cattle. Nellore cattle (male, 42 non-castrated [NCAST] and 44 castrated [CAST] were evaluated by both VS and US, at the postweaning (15-month old and finishing phases (21-month old. Visual scores of conformation (C, precocity (P and muscling (M were assessed and the backfat thickness (UBFT, rump fat thickness (URFT and ribeye area (UREA were measured by ultrasound. Gain-to-feed (G:F ratio and residual feed intake (RFI were measured in feedlot. Hot carcass weight, DP and RPY were determined at harvest. Non-castrated cattle had greater HCW and RPY but lower UBFT and URFT than CAST. Postweaning VS and US were poorly correlated with FE in both sexual conditions. Finishing VS were negatively correlated with G:F in CAST and finishing URFT was negatively correlated with RPY in NCAST. The relationship of VS and US with feed efficiency and meat yield is affected by age at the date of evaluation and by castration. Feed efficiency is not related to the yield of meat cuts in Nellore cattle

  19. Effectiveness of Commercial Biofertilizer on Fertilization Efficiency in Ultisols for the Growth and Yield of Caisim

    Directory of Open Access Journals (Sweden)

    Ea Kosman Anwar

    2011-09-01

    Full Text Available The effectiveness of Commercial Biofertilizer 1 (CBF1 on the growth and yield of caisim (Brassica sp. was examined in the greenhouse of Indonesian Soil Research Institute in Bogor. The completely randomized design (CRD was performed to examine the effects of Commercial Biofertilizer 1 (CBF1 on Fertilization Efficiency in Ultisols. The treatments were consists of 10 combinations between NPK-recommendation (NPK-rec and CBF1, with six replications. The experiment was conducted from August to October 2009. The result showed that CBF I increased the yields of caisim when combining by fertilizer NPK-rec, while giving CBF1 alone did not significantly increases yields compare to control (without fertilizer. Giving ¾ dosage NPK-rec. + CBF1 had RAE value 163%, indicating the effectiveness of CBF1 was optimum, that it reduce the need of NPK fertilizer by 25% by providing the increasing of yield 63% compared to NPK rec. The higher the level of NPK-rec. the lower the efficiency of fertilization. CBF1 had given effectives on yields when it was combined by inorganic fertilizer. However, when it was not combined with inorganic fertilizers, it would harm plants and decreased the soil nutrients. The influence of biofertilizer in plants were predictable unpredictable, while the influent of inorganic fertilizers were predictable.

  20. Effect of the use of molasses and efficient microorganisms, over the rate of decomposition of the sugar cane leaf (Saccharum officinarum

    Directory of Open Access Journals (Sweden)

    Óscar Eduardo Sanclemente Reyes

    2011-10-01

    Full Text Available The rate of decomposition of sugar cane leaves mixed with an organic fertilizer compost type was evaluated, using a finite accelerator (molasses and an infinity accelerator (effective microorganisms. The trial was conducted in the greenhouse facilities of the National University of Colombia in Palmira. The results showed that molasses is a decomposition accelerator of the wastes of sugar cane leaf, since it shows a marked influence on the initial decomposition rate of the waste, but once the carbohydrates that constitute it are consumed, the rate of decomposition decreases significantly. Then the potential is evident on the waste of sugar cane leaf elements for the maintenance and/or biophysical capital improvement in the productive system of the sugar cane, as the result of their high photosynthetic efficiency.

  1. Effect of Leaf Water Potential on Internal Humidity and CO2 Dissolution: Reverse Transpiration and Improved Water Use Efficiency under Negative Pressure.

    Science.gov (United States)

    Vesala, Timo; Sevanto, Sanna; Grönholm, Tiia; Salmon, Yann; Nikinmaa, Eero; Hari, Pertti; Hölttä, Teemu

    2017-01-01

    The pull of water from the soil to the leaves causes water in the transpiration stream to be under negative pressure decreasing the water potential below zero. The osmotic concentration also contributes to the decrease in leaf water potential but with much lesser extent. Thus, the surface tension force is approximately balanced by a force induced by negative water potential resulting in concavely curved water-air interfaces in leaves. The lowered water potential causes a reduction in the equilibrium water vapor pressure in internal (sub-stomatal/intercellular) cavities in relation to that over water with the potential of zero, i.e., over the flat surface. The curved surface causes a reduction also in the equilibrium vapor pressure of dissolved CO 2 , thus enhancing its physical solubility to water. Although the water vapor reduction is acknowledged by plant physiologists its consequences for water vapor exchange at low water potential values have received very little attention. Consequences of the enhanced CO 2 solubility to a leaf water-carbon budget have not been considered at all before this study. We use theoretical calculations and modeling to show how the reduction in the vapor pressures affects transpiration and carbon assimilation rates. Our results indicate that the reduction in vapor pressures of water and CO 2 could enhance plant water use efficiency up to about 10% at a leaf water potential of -2 MPa, and much more when water potential decreases further. The low water potential allows for a direct stomatal water vapor uptake from the ambient air even at sub-100% relative humidity values. This alone could explain the observed rates of foliar water uptake by e.g., the coastal redwood in the fog belt region of coastal California provided the stomata are sufficiently open. The omission of the reduction in the water vapor pressure causes a bias in the estimates of the stomatal conductance and leaf internal CO 2 concentration based on leaf gas exchange

  2. Leaf density explains variation in leaf mass per area in rice between cultivars and nitrogen treatments.

    Science.gov (United States)

    Xiong, Dongliang; Wang, Dan; Liu, Xi; Peng, Shaobing; Huang, Jianliang; Li, Yong

    2016-05-01

    Leaf mass per area (LMA) is an important leaf trait; however, correlations between LMA and leaf anatomical features and photosynthesis have not been fully investigated, especially in cereal crops. The objectives of this study were (a) to investigate the correlations between LMA and leaf anatomical traits; and (b) to clarify the response of LMA to nitrogen supply and its effect on photosynthetic nitrogen use efficiency (PNUE). In the present study, 11 rice varieties were pot grown under sufficient nitrogen (SN) conditions, and four selected rice cultivars were grown under low nitrogen (LN) conditions. Leaf anatomical traits, gas exchange and leaf N content were measured. There was large variation in LMA across selected rice varieties. Regression analysis showed that the variation in LMA was more closely related to leaf density (LD) than to leaf thickness (LT). LMA was positively related to the percentage of mesophyll tissue area (%mesophyll), negatively related to the percentage of epidermis tissue area (%epidermis) and unrelated to the percentage of vascular tissue area (%vascular). The response of LMA to N supplementation was dependent on the variety and was also mainly determined by the response of LD to N. Compared with SN, photosynthesis was significantly decreased under LN, while PNUE was increased. The increase in PNUE was more critical in rice cultivars with a higher LMA under SN supply. Leaf density is the major cause of the variation in LMA across rice varieties and N treatments, and an increase in LMA under high N conditions would aggravate the decrease in PNUE. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Carbon isotope discrimination as a selection tool for high water use efficiency and high crop yields

    International Nuclear Information System (INIS)

    Kumarasinghe, K.S.; Kirda, C.; Bowen, G.D.; Zapata, F.; Awonaike, K.O.; Holmgren, E.; Arslan, A.; De Bisbal, E.C.; Mohamed, A.R.A.G.; Montenegro, A.

    1996-01-01

    Results of back-up research conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in support of the FAO/IAEA Co-ordinated Research Programme on the Use of Isotope Studies on Increasing and Stabilizing Plant Productivity in Low Phosphate and Semi-arid and Sub-humid Soils of the Tropics and Sub-tropics, are presented here. Neutron probe measurements confirmed the earlier reports of a strong correlation of Δ with grain yield and water use efficiency of wheat. High soil gypsum content and soil salinity, a wide spread problem in soils of arid and semi-arid climatic zones, do not interfere with the association of Δ with crop yields, provided plants are grown in similar soil water status and soil fertility level. Results of a glasshouse experiment using selected cowpea genotypes showed that Δ values measured at flowering stage positively correlated with total dry matter production and percent N 2 derived from atmosphere (%Ndfa), contributing to an earlier report from the laboratory that it may be possible to use Δ values for screening of leguminous crops for high N 2 fixation potential. 13 C isotope discrimination in the leaves of Gliricidia sepium was measured to examine if the technique could be extended to studies with trees. Results of a glasshouse experiment with 18 provenances of Gliricidia sepium showed highly significant correlations of Δ with total dry matter production, water use efficiency and total N accumulated through biological nitrogen fixation. Although the correlation of Δ with water use efficiency and dry matter yield are relatively clear and better understood, the correlation with nitrogen fixation still needs a closer examination under different environmental conditions and with different species. While 13 C isotope discrimination may be a valuable tool for identifying annual crops with high water use efficiency and high yield potential, it may be more attractive for tree species considering the long growth periods taken for trees

  4. Effects of irrigation moisture regimes on yield and quality of paprika ( Capsicum annuum L)

    Science.gov (United States)

    Shongwe, Victor D.; Magongo, Bekani N.; Masarirambi, Michael T.; Manyatsi, Absalom M.

    Although paprika ( Capsicum annuum L) is not widely grown in Swaziland it is becoming increasingly popular as a spice and food colourant. It is a crop that requires irrigation at specific stages of growth as this affects not only the yield but most importantly the quality of the crop. Yield of paprika has been found to increase with relative increase in moisture whereas the quality of fruits has not followed the same trend. The objective of this study was to find the effect of varying irrigation water regimes on the yield and quality of paprika at uniform fertiliser levels. The study was carried out in the 2006/2007 cropping season at the Luyengo campus of the University of Swaziland in a greenhouse. A randomised complete block design was used with four water treatments (0.40, 0.60, 0.80, and 1.00 × Field Capacity). Parameters measured included leaf number per plant, plant height, chlorophyll content, canopy size, leaf width, leaf length, stem girth, dry mass, fresh mass, fruit length, and brix content. There were significant ( P < 0.05) increases in leaf number, plant height, chlorophyll content, canopy size, fresh and dry mass tops and fruit length at the highest moisture level (1.00 × FC) followed by the second highest regime (0.80 × FC) whilst the lower water regimes resulted in lower increases in each of the parameters. Leaf area index did not differ significantly across all treatments. In increasing order the treatments 0.80 × FC and 1.00 × FC gave higher yields but in decreasing order lower brix and thus subsequent lower paprika quality. It is recommended that growers who are aiming for optimum yield and high quality of paprika may use the 0.8 × FC treatment when irrigating.

  5. Genotypic variation in carbon isotope discrimination and transpiration efficiency in wheat. Leaf gas exchange and whole plant studies

    International Nuclear Information System (INIS)

    Condon, A.G.; Farquhar, G.D.; Richards, R.A.

    1990-01-01

    The relationship between carbon isotope discrimination, Δ, measured in plant dry matter and the ratio of intercellular to atmospheric partial pressures of CO 2 ,p i /p a , in leaves was examined in two glasshouse experiments using 14 wheat genotypes selected on the basis of variation in Δ of dry matter. Genotypic variation in Δ was similar in both experiments, with an average range of 1.8 x 10 -3 . Δ measured in dry matter and p i /p a measured in flag leaves were positively correlated. Variation among genotypes in p i /p a was attributed, approximately equally, to variation in leaf conductance and in photosynthetic capacity. The relationship between plant transpiration efficiency, W * (the amount of above-ground dry matter produced per unit water transpired) and Δ was was also examined. The results indicate that genotypic variation in Δ, measured in dry matter, should provide a reasonable measure of genotypic variation in long-term mean leaf p i /p a in wheat. 42 refs., 2 tabs., 5 figs

  6. Protoplast isolation, transient transformation of leaf mesophyll protoplasts and improved Agrobacterium-mediated leaf disc infiltration of Phaseolus vulgaris: tools for rapid gene expression analysis.

    Science.gov (United States)

    Nanjareddy, Kalpana; Arthikala, Manoj-Kumar; Blanco, Lourdes; Arellano, Elizabeth S; Lara, Miguel

    2016-06-24

    Phaseolus vulgaris is one of the most extensively studied model legumes in the world. The P. vulgaris genome sequence is available; therefore, the need for an efficient and rapid transformation system is more imperative than ever. The functional characterization of P. vulgaris genes is impeded chiefly due to the non-amenable nature of Phaseolus sp. to stable genetic transformation. Transient transformation systems are convenient and versatile alternatives for rapid gene functional characterization studies. Hence, the present work focuses on standardizing methodologies for protoplast isolation from multiple tissues and transient transformation protocols for rapid gene expression analysis in the recalcitrant grain legume P. vulgaris. Herein, we provide methodologies for the high-throughput isolation of leaf mesophyll-, flower petal-, hypocotyl-, root- and nodule-derived protoplasts from P. vulgaris. The highly efficient polyethylene glycol-mannitol magnesium (PEG-MMG)-mediated transformation of leaf mesophyll protoplasts was optimized using a GUS reporter gene. We used the P. vulgaris SNF1-related protein kinase 1 (PvSnRK1) gene as proof of concept to demonstrate rapid gene functional analysis. An RT-qPCR analysis of protoplasts that had been transformed with PvSnRK1-RNAi and PvSnRK1-OE vectors showed the significant downregulation and ectopic constitutive expression (overexpression), respectively, of the PvSnRK1 transcript. We also demonstrated an improved transient transformation approach, sonication-assisted Agrobacterium-mediated transformation (SAAT), for the leaf disc infiltration of P. vulgaris. Interestingly, this method resulted in a 90 % transformation efficiency and transformed 60-85 % of the cells in a given area of the leaf surface. The constitutive expression of YFP further confirmed the amenability of the system to gene functional characterization studies. We present simple and efficient methodologies for protoplast isolation from multiple P

  7. Genetic Improvements in Rice Yield and Concomitant Increases in Radiation- and Nitrogen-Use Efficiency in Middle Reaches of Yangtze River

    Science.gov (United States)

    Zhu, Guanglong; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao; Wang, Fei

    2016-01-01

    The yield potential of rice (Oryza sativa L.) has experienced two significant growth periods that coincide with the introduction of semi-dwarfism and the utilization of heterosis. In present study, we determined the annual increase in the grain yield of rice varieties grown from 1936 to 2005 in Middle Reaches of Yangtze River and examined the contributions of RUE (radiation-use efficiency, the conversion efficiency of pre-anthesis intercepted global radiation to biomass) and NUE (nitrogen-use efficiency, the ratio of grain yield to aboveground N accumulation) to these improvements. An examination of the 70-year period showed that the annual gains of 61.9 and 75.3 kg ha−1 in 2013 and 2014, respectively, corresponded to an annual increase of 1.18 and 1.16% in grain yields, respectively. The improvements in grain yield resulted from increases in the harvest index and biomass, and the sink size (spikelets per panicle) was significantly enlarged because of breeding for larger panicles. Improvements were observed in RUE and NUE through advancements in breeding. Moreover, both RUE and NUE were significantly correlated with the grain yield. Thus, our study suggests that genetic improvements in rice grain yield are associated with increased RUE and NUE. PMID:26876641

  8. Induced mutations for resistance to leaf rust in wheat

    International Nuclear Information System (INIS)

    Borojevic, K.

    1983-01-01

    Problems related to the induction of mutations for disease resistance were investigated under several aspects, using the wheat/leaf rust system. Previously selected mutant lines, tested in M 11 and M 13 , were found to differ with regard to infection type and disease severity from the original varieties. To verify the induced-mutation origin, these mutants were examined further using test crosses with carriers of known genes for leaf rust resistance and electrophoresis. A separate experiment to induce mutations for leaf rust resistance in the wheat varieties Sava, Aurora and Siete Cerros, using gamma rays, fast neutrons and EMS, yielded mutants with different disease reaction in the varieties Sava and Aurora at a frequency of about 1x10 - 3 per M 1 plant progenies. (author)

  9. Tomato Yield and Water Use Efficiency - Coupling Effects between Growth Stage Specific Soil Water Deficits

    DEFF Research Database (Denmark)

    Chen, Si; Zhenjiang, Zhou; Andersen, Mathias Neumann

    2015-01-01

    To investigate the sensitivity of tomato yield and water use efficiency (WUE) to soil water content at different growth stages, the central composite rotatable design (CCRD) was employed in a five-factor-five-level pot experiment under regulated deficit irrigation. Two regression models concerning...... the effects of stage-specific soil water content on tomato yield and WUE were established. The results showed that the lowest available soil water (ASW) content (around 28%) during vegetative growth stage (here denoted θ1) resulted in high yield and WUE. Moderate (around 69% ASW) during blooming and fruit...... effects of ASW in two growth stages were between θ2 and θ5, θ3. In both cases a moderate θ2 was a precondition for maximum yield response to increasing θ5 and θ3. Sensitivity analysis revealed that yield was most sensitive to soil water content at fruit maturity (θ5). Numerical inspection...

  10. Genetic control of late blight, yield and some yield related traits in tomato (lycopersicon esculentum mill.)

    International Nuclear Information System (INIS)

    Saleem, M.Y.; Asghar, M.; Khan, A.R.; Iqbal, Q.

    2011-01-01

    Genetic control of late blight (LB) and some economic traits was assessed to identify genotypes suitable for the hybrids were derived from crossing of 2 male sterile lines viz., development of late blight resistant hybrids in tomato. 10 F/sub 1/ hybrid were derived from crossing of 2 male sterile lines viz., TMS1 and TMS2 with 5 elite lines viz., Nagina, Riogrande, Roma, 88572 and Picdenato according to line x tester technique. Disease resistance was measured using detached leaf and whole plant assay techniques. Data were also recorded for days to maturity, number of fruit per plant, single fruit weight and yield per plant. The analysis of variance showed significant differences among crosses, lines, testers and line x tester interaction for almost all parameters. Estimate of genetic components indicated preponderance of additive type of gene action for detached leaf assay, whole plant assay, number of fruit per plant and yield per plant whereas non-additive type of gene action for days to maturity and single fruit weight. Among parents, TMS2, Nagina, Roma and Picdenato showed significant favorable general combing ability (GCA) effects for disease rating traits while TMS1 and Riogrande indicated desirable GCA effects for yield and some yield related traits. Among hybrids, TMS2 x Roma and TMS1 x Riogrande had significant specific combing ability (SCA) effects for detached and whole plant assays. However, hybrid TMS2 x Roma appeared as good combination of LB resistance as it had both parents with desirable GCA effects. All hybrids showed average type of SCA effects for yield and yield components. Genetic control of LB revealed that a multiple crossing program involving genotypes with high GCA effects would be rewarding to identify LB resistant genotypes in early generations. (author)

  11. Performance of Linear and Nonlinear Two-Leaf Light Use Efficiency Models at Different Temporal Scales

    Directory of Open Access Journals (Sweden)

    Xiaocui Wu

    2015-02-01

    Full Text Available The reliable simulation of gross primary productivity (GPP at various spatial and temporal scales is of significance to quantifying the net exchange of carbon between terrestrial ecosystems and the atmosphere. This study aimed to verify the ability of a nonlinear two-leaf model (TL-LUEn, a linear two-leaf model (TL-LUE, and a big-leaf light use efficiency model (MOD17 to simulate GPP at half-hourly, daily and 8-day scales using GPP derived from 58 eddy-covariance flux sites in Asia, Europe and North America as benchmarks. Model evaluation showed that the overall performance of TL-LUEn was slightly but not significantly better than TL-LUE at half-hourly and daily scale, while the overall performance of both TL-LUEn and TL-LUE were significantly better (p < 0.0001 than MOD17 at the two temporal scales. The improvement of TL-LUEn over TL-LUE was relatively small in comparison with the improvement of TL-LUE over MOD17. However, the differences between TL-LUEn and MOD17, and TL-LUE and MOD17 became less distinct at the 8-day scale. As for different vegetation types, TL-LUEn and TL-LUE performed better than MOD17 for all vegetation types except crops at the half-hourly scale. At the daily and 8-day scales, both TL-LUEn and TL-LUE outperformed MOD17 for forests. However, TL-LUEn had a mixed performance for the three non-forest types while TL-LUE outperformed MOD17 slightly for all these non-forest types at daily and 8-day scales. The better performance of TL-LUEn and TL-LUE for forests was mainly achieved by the correction of the underestimation/overestimation of GPP simulated by MOD17 under low/high solar radiation and sky clearness conditions. TL-LUEn is more applicable at individual sites at the half-hourly scale while TL-LUE could be regionally used at half-hourly, daily and 8-day scales. MOD17 is also an applicable option regionally at the 8-day scale.

  12. Global parameterization and validation of a two-leaf light use efficiency model for predicting gross primary production across FLUXNET sites: TL-LUE Parameterization and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yanlian [Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing China; Joint Center for Global Change Studies, Beijing China; Wu, Xiaocui [International Institute for Earth System Sciences, Nanjing University, Nanjing China; Joint Center for Global Change Studies, Beijing China; Ju, Weimin [International Institute for Earth System Sciences, Nanjing University, Nanjing China; Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application, Nanjing China; Chen, Jing M. [International Institute for Earth System Sciences, Nanjing University, Nanjing China; Joint Center for Global Change Studies, Beijing China; Wang, Shaoqiang [Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Science, Beijing China; Wang, Huimin [Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Science, Beijing China; Yuan, Wenping [State Key Laboratory of Earth Surface Processes and Resource Ecology, Future Earth Research Institute, Beijing Normal University, Beijing China; Andrew Black, T. [Faculty of Land and Food Systems, University of British Columbia, Vancouver British Columbia Canada; Jassal, Rachhpal [Faculty of Land and Food Systems, University of British Columbia, Vancouver British Columbia Canada; Ibrom, Andreas [Department of Environmental Engineering, Technical University of Denmark (DTU), Kgs. Lyngby Denmark; Han, Shijie [Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang China; Yan, Junhua [South China Botanical Garden, Chinese Academy of Sciences, Guangzhou China; Margolis, Hank [Centre for Forest Studies, Faculty of Forestry, Geography and Geomatics, Laval University, Quebec City Quebec Canada; Roupsard, Olivier [CIRAD-Persyst, UMR Ecologie Fonctionnelle and Biogéochimie des Sols et Agroécosystèmes, SupAgro-CIRAD-INRA-IRD, Montpellier France; CATIE (Tropical Agricultural Centre for Research and Higher Education), Turrialba Costa Rica; Li, Yingnian [Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining China; Zhao, Fenghua [Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Science, Beijing China; Kiely, Gerard [Environmental Research Institute, Civil and Environmental Engineering Department, University College Cork, Cork Ireland; Starr, Gregory [Department of Biological Sciences, University of Alabama, Tuscaloosa Alabama USA; Pavelka, Marian [Laboratory of Plants Ecological Physiology, Institute of Systems Biology and Ecology AS CR, Prague Czech Republic; Montagnani, Leonardo [Forest Services, Autonomous Province of Bolzano, Bolzano Italy; Faculty of Sciences and Technology, Free University of Bolzano, Bolzano Italy; Wohlfahrt, Georg [Institute for Ecology, University of Innsbruck, Innsbruck Austria; European Academy of Bolzano, Bolzano Italy; D' Odorico, Petra [Grassland Sciences Group, Institute of Agricultural Sciences, ETH Zurich Switzerland; Cook, David [Atmospheric and Climate Research Program, Environmental Science Division, Argonne National Laboratory, Argonne Illinois USA; Arain, M. Altaf [McMaster Centre for Climate Change and School of Geography and Earth Sciences, McMaster University, Hamilton Ontario Canada; Bonal, Damien [INRA Nancy, UMR EEF, Champenoux France; Beringer, Jason [School of Earth and Environment, The University of Western Australia, Crawley Australia; Blanken, Peter D. [Department of Geography, University of Colorado Boulder, Boulder Colorado USA; Loubet, Benjamin [UMR ECOSYS, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon France; Leclerc, Monique Y. [Department of Crop and Soil Sciences, College of Agricultural and Environmental Sciences, University of Georgia, Athens Georgia USA; Matteucci, Giorgio [Viea San Camillo Ed LellisViterbo, University of Tuscia, Viterbo Italy; Nagy, Zoltan [MTA-SZIE Plant Ecology Research Group, Szent Istvan University, Godollo Hungary; Olejnik, Janusz [Meteorology Department, Poznan University of Life Sciences, Poznan Poland; Department of Matter and Energy Fluxes, Global Change Research Center, Brno Czech Republic; Paw U, Kyaw Tha [Department of Land, Air and Water Resources, University of California, Davis California USA; Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge USA; Varlagin, Andrej [A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow Russia

    2016-04-06

    Light use efficiency (LUE) models are widely used to simulate gross primary production (GPP). However, the treatment of the plant canopy as a big leaf by these models can introduce large uncertainties in simulated GPP. Recently, a two-leaf light use efficiency (TL-LUE) model was developed to simulate GPP separately for sunlit and shaded leaves and has been shown to outperform the big-leaf MOD17 model at 6 FLUX sites in China. In this study we investigated the performance of the TL-LUE model for a wider range of biomes. For this we optimized the parameters and tested the TL-LUE model using data from 98 FLUXNET sites which are distributed across the globe. The results showed that the TL-LUE model performed in general better than the MOD17 model in simulating 8-day GPP. Optimized maximum light use efficiency of shaded leaves (εmsh) was 2.63 to 4.59 times that of sunlit leaves (εmsu). Generally, the relationships of εmsh and εmsu with εmax were well described by linear equations, indicating the existence of general patterns across biomes. GPP simulated by the TL-LUE model was much less sensitive to biases in the photosynthetically active radiation (PAR) input than the MOD17 model. The results of this study suggest that the proposed TL-LUE model has the potential for simulating regional and global GPP of terrestrial ecosystems and it is more robust with regard to usual biases in input data than existing approaches which neglect the bi-modal within-canopy distribution of PAR.

  13. Effects of submicron ammonium sulfate particles on the growth and yield of komatsuna (Brassica rapa L. var. perviridis)

    Science.gov (United States)

    Motai, Akira; Nakaba, Satoshi; Lenggoro, I. Wuled; Watanabe, Makoto; Wada, Yoshiharu; Izuta, Takeshi

    2017-11-01

    The aim of this study was to determine the effects of submicron ammonium sulfate (AS) particles on komatsuna (Brassica rapa L. cv. Hakkei) plants. First, we optimized a leaf-washing method to measure the amount of AS particles deposited on the leaf surface of the plants. Then, we used this method to determine the retention time of particles deposited on the leaf surface of the plants. We also investigated the effects of AS particles on the growth and yield of the plants. Almost all the AS particles deposited on the leaf surface were removed within 1 min washing time with ultrapure water, and ion leaching from the leaf was relatively slow but continuous during the leaf-washing procedure. On the basis of these results, we determined that 1 min was a suitable washing time to remove most of the AS particles while minimizing the influence of ion leaching from the leaf. The amount of particulate SO42- deposited on the leaf surface decreased over time, probably because AS particles deposited on the leaf surface deliquesced, allowing ions such as SO42- in the deliquescence solution to be absorbed into the leaf. The plants were grown and exposed to AS particles for 16 days in naturally lit phytotrons. The daily mean increase in the concentration of SO42- in PM2.5 by the exposure to AS particles was 22.5 μg m-3 in the phytotrons. The growth and yield of the plants were significantly reduced by the exposure to AS particles. The exposure to AS particles did not affect the leaf concentrations of nitrogen and chlorophyll, but significantly reduced stomatal conductance. Therefore, stomatal closure is one of the reasons for the AS particle-induced reductions in the growth and yield of komatsuna plants.

  14. Variation in the carbon and oxygen isotope composition of plant biomass and its relationship to water-use efficiency at the leaf- and ecosystem-scales in a northern Great Plains grassland.

    Science.gov (United States)

    Flanagan, Lawrence B; Farquhar, Graham D

    2014-02-01

    Measurements of the carbon (δ(13) Cm ) and oxygen (δ(18) Om ) isotope composition of C3 plant tissue provide important insights into controls on water-use efficiency. We investigated the causes of seasonal and inter-annual variability in water-use efficiency in a grassland near Lethbridge, Canada using stable isotope (leaf-scale) and eddy covariance measurements (ecosystem-scale). The positive relationship between δ(13) Cm and δ(18) Om values for samples collected during 1998-2001 indicated that variation in stomatal conductance and water stress-induced changes in the degree of stomatal limitation of net photosynthesis were the major controls on variation in δ(13) Cm and biomass production during this time. By comparison, the lack of a significant relationship between δ(13) Cm and δ(18) Om values during 2002, 2003 and 2006 demonstrated that water stress was not a significant limitation on photosynthesis and biomass production in these years. Water-use efficiency was higher in 2000 than 1999, consistent with expectations because of greater stomatal limitation of photosynthesis and lower leaf ci /ca during the drier conditions of 2000. Calculated values of leaf-scale water-use efficiency were 2-3 times higher than ecosystem-scale water-use efficiency, a difference that was likely due to carbon lost in root respiration and water lost during soil evaporation that was not accounted for by the stable isotope measurements. © 2013 John Wiley & Sons Ltd.

  15. Method for continuous measurement of export from a leaf

    International Nuclear Information System (INIS)

    Geiger, D.R.; Fondy, B.R.

    1979-01-01

    Export of labeled material derived by continuous photosynthesis in 14 CO 2 was monitored with a Geiger-Mueller detector positioned next to an exporting leaf blade. Rate of export of labeled material was calculated from the difference between rates of retention and net photosynthesis of labeled carbon for the observed leaf. Given certain conditions, including nearly constant distribution of labeled material among minor veins and various types of cells, count rate data for the source leaf can be coverted to rate of export of carbon. Changes in counting efficiency resulting from changes in leaf water status can be corrected for with data from a transducer which measures leaf thickness. Export data agreed with data obtained by monitoring the arrival of 14 C in the sink region; isolated leaves gave values near zero for export of labeled carbon from a given leaf on an intact plant. The technique detects changes in export with a resolution of 10 to 20 minutes

  16. Maize growth and yield in Peshawar under changing climate

    International Nuclear Information System (INIS)

    Shah, A.; Akmal, M.; Asim, M.

    2012-01-01

    Global climate change is consequence of accumulating greenhouse gases (Carbon) at lower atmosphere which might affects crops growth and yield. Maize is an important summer cereals, grown on considerable area in Pakistan every year. We, therefore, study the delay sowing response with changing climate on maize. Field experiment was conducted at Agronomy Research Farm, Agricultural University Peshawar, Pakistan in a randomized complete block design. Sowing was done from June 8 to July 24, 2010 with ten days intervals. Mazie (cv. Azam) was planted in rows at 0.75 m distance in NS orientations. Crop was raised under the uniform recommended cultural practices. Data regarding days to emergence, tasseling and maturity showed a consecutive decrease when so wing was delayed form June 08 onwards. However, the crop life cycle (i.e. vegetative and reproductive durations) initially remained uniform but expanded for late sowing dates (July). Delay sowing showed an increase in the leaf area index with an abrupt decline for the late sown crop. Nonetheless, plant stand at harvest remained static during the growth for all sowing dates. A stable to moderate reduction was noticed in ear length (cm) when sowings was delayed from Jun 08 onwards. Grain rows cob/-1 did not influence by the delay sowing in the season. Moreover, delay sowing did not show any significant (P<0.05) change for the grain number. However, thousand grains weight was initially remained stable but declined (P<0.05) by delay in sowing. Biological yield, dry matter and grains yield (g m/sup -2/) revealed almost a similar decreasing trend when sowing was delayed. Dry matter to grain yield relationship was linear (r/sup 2/ = 0.95) and revealed a mean loss of 1.65 g m/sup 2/ when sowing delayed from June 08 to July 24 in the season. Radiation use efficiency (RUE), the growth function, was also declined by the delay in sowing. We inferred that losses in leaf area indices, ear length and grain weights were basis of the

  17. A Novel Diffuse Fraction-Based Two-Leaf Light Use Efficiency Model: An Application Quantifying Photosynthetic Seasonality across 20 AmeriFlux Flux Tower Sites

    Science.gov (United States)

    Yan, Hao; Wang, Shao-Qiang; Yu, Kai-Liang; Wang, Bin; Yu, Qin; Bohrer, Gil; Billesbach, Dave; Bracho, Rosvel; Rahman, Faiz; Shugart, Herman H.

    2017-10-01

    Diffuse radiation can increase canopy light use efficiency (LUE). This creates the need to differentiate the effects of direct and diffuse radiation when simulating terrestrial gross primary production (GPP). Here, we present a novel GPP model, the diffuse-fraction-based two-leaf model (DTEC), which includes the leaf response to direct and diffuse radiation, and treats maximum LUE for shaded leaves (ɛmsh defined as a power function of the diffuse fraction (Df)) and sunlit leaves (ɛmsu defined as a constant) separately. An Amazonian rainforest site (KM67) was used to calibrate the model by simulating the linear relationship between monthly canopy LUE and Df. This showed a positive response of forest GPP to atmospheric diffuse radiation, and suggested that diffuse radiation was more limiting than global radiation and water availability for Amazon rainforest GPP on a monthly scale. Further evaluation at 20 independent AmeriFlux sites showed that the DTEC model, when driven by monthly meteorological data and MODIS leaf area index (LAI) products, explained 70% of the variability observed in monthly flux tower GPP. This exceeded the 51% accounted for by the MODIS 17A2 big-leaf GPP product. The DTEC model's explicit accounting for the impacts of diffuse radiation and soil water stress along with its parameterization for C4 and C3 plants was responsible for this difference. The evaluation of DTEC at Amazon rainforest sites demonstrated its potential to capture the unique seasonality of higher GPP during the diffuse radiation-dominated wet season. Our results highlight the importance of diffuse radiation in seasonal GPP simulation.Plain Language SummaryAs diffuse radiation can increase canopy light use efficiency (LUE), there is a need to differentiate the effects of direct and diffuse radiation in simulating terrestrial gross primary production (GPP). A novel diffuse-fraction (Df)-based two leaf GPP model (DTEC) developed by this study considers these effects. Evaluation

  18. Tradeoff between stem hydraulic efficiency and mechanical strength affects leaf-stem allometry in 28 Ficus tree species

    NARCIS (Netherlands)

    Fan, Ze Xin; Sterck, Frank; Zhang, Shi Bao; Fu, Pei Li; Hao, Guang You

    2017-01-01

    Leaf-stem allometry is an important spectrum that linked to biomass allocation and life history strategy in plants, although the determinants and evolutionary significance of leaf-stem allometry remain poorly understood. Leaf and stem architectures - including stem area/mass, petiole area/mass,

  19. Increased sbpase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions

    NARCIS (Netherlands)

    Driever, Steven M.; Simkin, Andrew J.; Alotaibi, Saqer; Fisk, Stuart J.; Madgwick, Pippa J.; Sparks, Caroline A.; Jones, Huw D.; Lawson, Tracy; Parry, Martin A.J.; Raines, Christine A.

    2017-01-01

    To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf

  20. Phenotyping Drought Tolerance and Yield Potential of Warm-Season Legumes Through Field- and Airborne-Based Hyperspectral VSWIR Sensing

    Science.gov (United States)

    Drewry, D.; Berny-Mier y Teran, J. C.; Dutta, D.; Gepts, P.

    2017-12-01

    Hyperspectral sensing in the visible through shortwave infrared (VSWIR) portion of the spectrum has been demonstrated to provide significant information on the structural and functional properties of vegetation, resulting in powerful techniques to discern species differences, characterize crop nutrient or water stress, and quantify the density of foliage in agricultural fields. Modern machine-learning techniques allow for the entire set of spectral bands, on the order of hundreds with modern field and airborne spectrometers, to be used to develop models that can simultaneously retrieve a variety of foliar chemical compounds and hydrological and structural states. The application of these techniques, in the context of leaf-level measurements of VSWIR reflectance, or more complicated remote airborne surveys, has the potential to revolutionize high-throughput methods to phenotype germplasm that optimizes yield, resource-use efficiencies, or alternate objectives related to disease resistance or biomass accumulation, for example. Here we focus on breeding trials for a set of warm-season legumes, conducted in both greenhouse and field settings, and spanning a set of diverse genotypes providing a range of adaptation to drought and yield potential in the context of the semi-arid climate cultivation. At the leaf-level, a large set of spectral reflectance measurements spanning 400-2500 nanometers were made for plants across various growth stages in field experiments that induced severe drought, along with sampling for relevant trait values. Here we will discuss the development and performance of algorithms for a range of leaf traits related to gas exchange, leaf structure, hydrological status, nutrient contents and stable isotope discrimination, along with their relationships to drought resistance and yield. We likewise discuss the effectiveness of quantifying relevant foliar and canopy traits through airborne imaging spectroscopy from small unmanned vehicles (sUAVs), and

  1. Relationships of leaf dark respiration to leaf nitrogen, specific leaf area and leaf life-span: a test across biomes and functional groups.

    Science.gov (United States)

    Reich, Peter B; Walters, Michael B; Ellsworth, David S; Vose, James M; Volin, John C; Gresham, Charles; Bowman, William D

    1998-05-01

    Based on prior evidence of coordinated multiple leaf trait scaling, we hypothesized that variation among species in leaf dark respiration rate (R d ) should scale with variation in traits such as leaf nitrogen (N), leaf life-span, specific leaf area (SLA), and net photosynthetic capacity (A max ). However, it is not known whether such scaling, if it exists, is similar among disparate biomes and plant functional types. We tested this idea by examining the interspecific relationships between R d measured at a standard temperature and leaf life-span, N, SLA and A max for 69 species from four functional groups (forbs, broad-leafed trees and shrubs, and needle-leafed conifers) in six biomes traversing the Americas: alpine tundra/subalpine forest, Colorado; cold temperate forest/grassland, Wisconsin; cool temperate forest, North Carolina; desert/shrubland, New Mexico; subtropical forest, South Carolina; and tropical rain forest, Amazonas, Venezuela. Area-based R d was positively related to area-based leaf N within functional groups and for all species pooled, but not when comparing among species within any site. At all sites, mass-based R d (R d-mass ) decreased sharply with increasing leaf life-span and was positively related to SLA and mass-based A max and leaf N (leaf N mass ). These intra-biome relationships were similar in shape and slope among sites, where in each case we compared species belonging to different plant functional groups. Significant R d-mass -N mass relationships were observed in all functional groups (pooled across sites), but the relationships differed, with higher R d at any given leaf N in functional groups (such as forbs) with higher SLA and shorter leaf life-span. Regardless of biome or functional group, R d-mass was well predicted by all combinations of leaf life-span, N mass and/or SLA (r 2 ≥ 0.79, P morphological, chemical and metabolic traits.

  2. Evaluating potassium-use-efficiency of five cotton genotypes of pakistan

    International Nuclear Information System (INIS)

    Hassan, Z.U.; Kubar, K.A.

    2014-01-01

    Potassium (K) deficiency in Pakistani soils has been recently reported as the major limiting factor affecting sustainable cotton production. The present study was conducted to envisage how K nutrition affect the growth, biomass production, yield and K-use-efficiency of five cotton genotypes, NIBGE-3701, NIBGE-1524 (Bt-transgenic), Sadori, Sindh-1 and SAU-2 (non-Bt conventional), commonly grown in Pakistan. All five genotypes were raised at deficient and adequate K levels, i.e. 0 and 60 kg K/sub 2/O ha-1, respectively. The experiment was performed in plastic pots following a completely randomized factorial design with three repeats. Adequate K nutrition significantly increased various plant growth traits and yield of all cotton genotypes under study, viz. number of sympodia (21%), number of leaves (34%), leaf dry biomass (30%), shoot dry biomass (31%), number of bolls (50%) and yield of seed cotton (92%). Substantial variations were observed among cotton genotypes for their K-use-efficiency and K-response-efficiency. Sadori and SAU-2 were screened as most K-use-efficient cotton genotypes, while Sindh-1 and SAU-2 were ranked as the most K-responsive cotton genotypes. Interestingly, Sadori did not respond to K nutrition. Moreover, Bt cotton genotypes accumulated more K as compared to non-Bt genotypes. The cotton genotype SAU-2 was identified as efficient-response genotype for better adaptation for both low- and high-K-input sustainable cotton agriculture systems. (author)

  3. Genetic variance of sunflower yield components - Heliantus annuus L.

    Directory of Open Access Journals (Sweden)

    Hladni Nada

    2003-01-01

    Full Text Available The main goals of sunflower breeding in Yugoslavia and abroad are increased seed yield and oil content per unit area and increased resistance to diseases, insects and stress conditions via an optimization of plant architecture. In order to determine the mode of inheritance, gene effects and correlations of total leaf number per plant, total leaf area and plant height, six genetically divergent inbred lines of sunflower were subjected to half diallel crosses. Significant differences in mean values of all the traits were found in the F1 and F2 generations. Additive gene effects were more important in the inheritance of total leaf number per plant and plant height, while in the case of total leaf area per plant the nonadditive ones were more important looking at all the combinations in the F1 and F2 generations. The average degree of dominance (Hi/D1/2 was lower than one for total leaf number per plant and plant height, so the mode of inheritance was partial dominance, while with total leaf area the value was higher than one, indicating super dominance as the mode of inheritance. Significant positive correlation was found: between total leaf area per plant and total leaf number per plant (0.285* and plant height (0.278*. The results of the study are of importance for further sunflower breeding work.

  4. Photosynthetic capacity, nutrient status and growth of maize (Zea mays L. upon MgSO4 leaf-application

    Directory of Open Access Journals (Sweden)

    Mareike eJezek

    2015-01-01

    Full Text Available The major plant nutrient magnesium is involved in numerous physiological processes and its deficiency can severely reduce the yield and quality of crops. Since Mg availability in soil and uptake into the plant is often limited by unfavorable soil or climatic conditions, application of Mg onto leaves, the site with highest physiological Mg demand, might be a reasonable alternative fertilization strategy. This study aimed to investigate, if MgSO4 leaf-application in practically relevant amounts can efficiently alleviate the effects of Mg starvation in maize, namely reduced photosynthesis capacity, disturbed ion homeostasis and growth depression. Results clearly demonstrated that Mg deficiency could be mitigated by MgSO4 leaf-application as efficiently as by resupply of MgSO4 via the roots in vegetative maize plants. Significant increases in SPAD values and net rate of CO2-assimilation as well as enhanced shoot biomass have been achieved. Ion analysis furthermore revealed an improvement of the nutrient status of Mg-deficient plants with regard to [Mg], [K] and [Mn] in distinct organs, thereby reducing the risk of Mn-toxicity at the rootside, which often occurs together with Mg deficiency on acid soils. In conclusion, foliar fertilization with Mg proved to be an efficient strategy to adequately supply maize plants with magnesium and might hence be of practical relevance to correct nutrient deficiencies during the growing season.

  5. High frequency organogenesis in hypocotyl, cotyledon, leaf and petiole explants of broccoli (Brassica oleracea L. var. italica), an important vegetable crop.

    Science.gov (United States)

    Kumar, Pankaj; Srivastava, D K

    2015-04-01

    Broccoli (Brassica oleracea L. var. italica) is an important, nutritionally rich vegetable crop, but severely affected by environmental stresses, pests and diseases which cause massive yield and quality losses. Genetic manipulation is becoming an important method for broccoli improvement. In the present study, a reproducible and highly efficient protocol for obtaining organogenesis from hypocotyl, cotyledon, leaf and petiole explants of broccoli (Brassica oleracea L. var. italica cv. Solan green head) has been developed. Hypocotyl and cotyledon explants were used from 10 to 12 days old aseptically grown seedlings whereas leaf and petiole explants were excised from 18 to 20 days old green house grown seedlings and surface sterilized. These explants were cultured on shoot induction medium containing different concentration and combination of BAP and NAA. High efficiency shoot regeneration has been achieved in hypocotyl (83.33 %), cotyledon (90.11 %), leaf (62.96 %) and petiole (91.10 %) explants on MS medium supplemented with 3.5 mg/l BAP + 0.019 mg/l NAA 2.5 mg/l BAP + 0.5 mg/l NAA, 4.0 mg/l BAP + 0.5 mg/l NAA and 4.5 mg/l BAP + 0.019 mg/l NAA respectively. Petiole explants showed maximum shoot regeneration response as compared to other explants. MS medium supplemented with 0.10 mg/l NAA was found best for root regeneration (100 %) from in vitro developed shoots. The regenerated complete plantlets were transferred to the pots containing cocopeat and successfully acclimatized. This optimized regeneration protocol can be efficiently used for genetic transformation in broccoli. This is the first comparative report on multiple shoot induction using four different types of explants viz. hypocotyl, cotyledon, leaf and petiole.

  6. Changes in Leaf Anatomical Traits Enhanced Photosynthetic Activity of Soybean Grown in Hydroponics with Plant Growth-Promoting Microorganisms.

    Science.gov (United States)

    Paradiso, Roberta; Arena, Carmen; De Micco, Veronica; Giordano, Maria; Aronne, Giovanna; De Pascale, Stefania

    2017-01-01

    The use of hydroponic systems for cultivation in controlled climatic conditions and the selection of suitable genotypes for the specific environment help improving crop growth and yield. We hypothesized that plant performance in hydroponics could be further maximized by exploiting the action of plant growth-promoting organisms (PGPMs). However, the effects of PGPMs on plant physiology have been scarcely investigated in hydroponics. Within a series of experiments aimed to identify the best protocol for hydroponic cultivation of soybean [ Glycine max (L.) Merr.], we evaluated the effects of a PGPMs mix, containing bacteria, yeasts, mycorrhiza and trichoderma beneficial species on leaf anatomy, photosynthetic activity and plant growth of soybean cv. 'Pr91m10' in closed nutrient film technique (NFT). Plants were grown in a growth chamber under semi-aseptic conditions and inoculated at seed, seedling and plant stages, and compared to non-inoculated (control) plants. Light and epi-fluorescence microscopy analyses showed that leaves of inoculated plants had higher density of smaller stomata (297 vs. 247 n/mm 2 ), thicker palisade parenchyma (95.0 vs. 85.8 μm), and larger intercellular spaces in the mesophyll (57.5% vs. 52.2%), compared to non-inoculated plants. The modifications in leaf functional anatomical traits affected gas exchanges; in fact starting from the reproductive phase, the rate of leaf net photosynthesis (NP) was higher in inoculated compared to control plants (8.69 vs. 6.13 μmol CO 2 m -2 s -1 at the beginning of flowering). These data are consistent with the better maximal PSII photochemical efficiency observed in inoculated plants (0.807 vs. 0.784 in control); conversely no difference in leaf chlorophyll content was found. The PGPM-induced changes in leaf structure and photosynthesis lead to an improvement of plant growth (+29.9% in plant leaf area) and seed yield (+36.9%) compared to control. Our results confirm that PGPMs may confer benefits in

  7. Changes in Leaf Anatomical Traits Enhanced Photosynthetic Activity of Soybean Grown in Hydroponics with Plant Growth-Promoting Microorganisms

    Directory of Open Access Journals (Sweden)

    Roberta Paradiso

    2017-05-01

    Full Text Available The use of hydroponic systems for cultivation in controlled climatic conditions and the selection of suitable genotypes for the specific environment help improving crop growth and yield. We hypothesized that plant performance in hydroponics could be further maximized by exploiting the action of plant growth-promoting organisms (PGPMs. However, the effects of PGPMs on plant physiology have been scarcely investigated in hydroponics. Within a series of experiments aimed to identify the best protocol for hydroponic cultivation of soybean [Glycine max (L. Merr.], we evaluated the effects of a PGPMs mix, containing bacteria, yeasts, mycorrhiza and trichoderma beneficial species on leaf anatomy, photosynthetic activity and plant growth of soybean cv. ‘Pr91m10’ in closed nutrient film technique (NFT. Plants were grown in a growth chamber under semi-aseptic conditions and inoculated at seed, seedling and plant stages, and compared to non-inoculated (control plants. Light and epi-fluorescence microscopy analyses showed that leaves of inoculated plants had higher density of smaller stomata (297 vs. 247 n/mm2, thicker palisade parenchyma (95.0 vs. 85.8 μm, and larger intercellular spaces in the mesophyll (57.5% vs. 52.2%, compared to non-inoculated plants. The modifications in leaf functional anatomical traits affected gas exchanges; in fact starting from the reproductive phase, the rate of leaf net photosynthesis (NP was higher in inoculated compared to control plants (8.69 vs. 6.13 μmol CO2 m-2 s-1 at the beginning of flowering. These data are consistent with the better maximal PSII photochemical efficiency observed in inoculated plants (0.807 vs. 0.784 in control; conversely no difference in leaf chlorophyll content was found. The PGPM-induced changes in leaf structure and photosynthesis lead to an improvement of plant growth (+29.9% in plant leaf area and seed yield (+36.9% compared to control. Our results confirm that PGPMs may confer benefits in

  8. Interaction effect of phosphorus and boron on yield and quality of lettuce

    Directory of Open Access Journals (Sweden)

    Sultana Zaman Chowdhury

    2015-12-01

    Full Text Available Proper nutrition is essential for satisfactory crop growth and production. A field experiment was conducted at Bangabandhu Sheikh Mujibur Rahman Agricultural University, to evaluate yield and quality of Grand Rapids lettuce using various levels of phosphorus and boron. Treatment combination of 120 kg ha-1 of phosphorus and 2 kg ha-1 of boron has significantly increased plant height, leaf number, leaf length, plant canopy, capsules plant-1, seeds capsule-1, seeds number plant-1, seed yield ha-1, germination (%, planting value (%, moisture (%, purity (%, dry matter (% and 1000 seed weight. Most of the treatment combinations performed better than control treatments in all parameter. The finding could be helpful to determine the precise levels of phosphorus and boron to improve the yield and quality of lettuce.

  9. Relating Stomatal Conductance to Leaf Functional Traits.

    Science.gov (United States)

    Kröber, Wenzel; Plath, Isa; Heklau, Heike; Bruelheide, Helge

    2015-10-12

    Leaf functional traits are important because they reflect physiological functions, such as transpiration and carbon assimilation. In particular, morphological leaf traits have the potential to summarize plants strategies in terms of water use efficiency, growth pattern and nutrient use. The leaf economics spectrum (LES) is a recognized framework in functional plant ecology and reflects a gradient of increasing specific leaf area (SLA), leaf nitrogen, phosphorus and cation content, and decreasing leaf dry matter content (LDMC) and carbon nitrogen ratio (CN). The LES describes different strategies ranging from that of short-lived leaves with high photosynthetic capacity per leaf mass to long-lived leaves with low mass-based carbon assimilation rates. However, traits that are not included in the LES might provide additional information on the species' physiology, such as those related to stomatal control. Protocols are presented for a wide range of leaf functional traits, including traits of the LES, but also traits that are independent of the LES. In particular, a new method is introduced that relates the plants' regulatory behavior in stomatal conductance to vapor pressure deficit. The resulting parameters of stomatal regulation can then be compared to the LES and other plant functional traits. The results show that functional leaf traits of the LES were also valid predictors for the parameters of stomatal regulation. For example, leaf carbon concentration was positively related to the vapor pressure deficit (vpd) at the point of inflection and the maximum of the conductance-vpd curve. However, traits that are not included in the LES added information in explaining parameters of stomatal control: the vpd at the point of inflection of the conductance-vpd curve was lower for species with higher stomatal density and higher stomatal index. Overall, stomata and vein traits were more powerful predictors for explaining stomatal regulation than traits used in the LES.

  10. Leaf-IT: An Android application for measuring leaf area.

    Science.gov (United States)

    Schrader, Julian; Pillar, Giso; Kreft, Holger

    2017-11-01

    The use of plant functional traits has become increasingly popular in ecological studies because plant functional traits help to understand key ecological processes in plant species and communities. This also includes changes in diversity, inter- and intraspecific interactions, and relationships of species at different spatiotemporal scales. Leaf traits are among the most important traits as they describe key dimensions of a plant's life history strategy. Further, leaf area is a key parameter with relevance for other traits such as specific leaf area, which in turn correlates with leaf chemical composition, photosynthetic rate, leaf longevity, and carbon investment. Measuring leaf area usually involves the use of scanners and commercial software and can be difficult under field conditions. We present Leaf-IT, a new smartphone application for measuring leaf area and other trait-related areas. Leaf-IT is free, designed for scientific purposes, and runs on Android 4 or higher. We tested the precision and accuracy using objects with standardized area and compared the area measurements of real leaves with the well-established, commercial software WinFOLIA using the Altman-Bland method. Area measurements of standardized objects show that Leaf-IT measures area with high accuracy and precision. Area measurements with Leaf-IT of real leaves are comparable to those of WinFOLIA. Leaf-IT is an easy-to-use application running on a wide range of smartphones. That increases the portability and use of Leaf-IT and makes it possible to measure leaf area under field conditions typical for remote locations. Its high accuracy and precision are similar to WinFOLIA. Currently, its main limitation is margin detection of damaged leaves or complex leaf morphologies.

  11. [Effects of plastic film mulching and rain harvesting modes on chlorophyll fluorescence characteristics, yield and water use efficiency of dryland maize].

    Science.gov (United States)

    Li, Shang-Zhong; Fan, Ting-Lu; Wang, Yong; Zhao, Gang; Wang, Lei; Tang, Xiao-Ming; Dang, Yi; Zhao, Hui

    2014-02-01

    The differences on chlorophyll fluorescence parameters, yield and water use efficiency of dryland maize were compared among full plastic film mulching on double ridges and planting in catchment furrows (FFDRF), half plastic film mulching on double ridges and planting in catchment furrows (HFDRF), plastic film mulching on ridge and planting in film-side (FS), and flat planting with no plastic film mulching (NM) under field conditions in dry highland of Loess Plateau in 2007-2012. The results showed that fluorescence yield (Fo), the maximum fluorescence yield (Fm), light-adapted fluorescence yield when PS II reaction centers were totally open (F), light-adapted fluorescence yield when PS II reaction centers closed (Fm'), the maximal photochemical efficiency of PS II (Fv/Fm), the actual photochemical efficiency of PS II in the light (Phi PS II), the relative electron transport rate (ETR), photochemical quenching (qP) and non-photochemical quenching (qN) in maize leaves of FFDRF were higher than that of control (NM), and the value of 1-qP was lower than that of control, at 13:00, chlorophyll fluorescence parameters values of FFDRF was significantly higher than control, which were increased by 5.3%, 56.8%, 10.7%, 36.3%, 23.6%, 56.7%, 64.4%, 45.5%, 23.6% and -55.6%, respectively, compared with the control. Yield and water use efficiency of FFDRF were the highest in every year no matter dry year, normal year, humid year and hail disaster year. Average yield and water use efficiency of FFDRF were 12,650 kg x hm(-2) and 40.4 kg x mm(-1) x hm(-2) during 2007-2012, increased by 57.8% and 61.6% compared with the control, respectively, and also significantly higher compared with HFDRF and PS. Therefore, it was concluded that FFDRF had significantly increased the efficiency of light energy conversion and improved the production capacity of dryland maize.

  12. Improving Wheat Growth and Yield Using Chlormequat Chloride, Salicylic Acid and Jasmonic Acid under Water Stress

    Directory of Open Access Journals (Sweden)

    N Vahabi

    2017-06-01

    measured by a water meter. Results and Discussion The results showed that water stress decreased flag leaf area, ear length, grain number per ear, biological yield and grain yield in the greenhouse and biological yield and grain yield in the field experiment. The maximum of flag leaf area was obtained at anthesis and after that there was no increase in green area. In the other hand, ear length and grain number per ear were fixed at anthesis and so drought stress had less negative impact on flag leaf area, ear length and grain number per ear under field conditions. Increasing the level of drought stress was considerably associated with greater reduction in grain yield and yield components. However, PGRS application improved yield components and consequently enhanced the grain yield. The higher flag leaf area in PGRs-treated plants might be due to lowering developmental rate or delaying plant maturity and senescence. So, by improving leaf area, PGR application resulted in increased photosynthetic rate leading to a higher yield. Although all PGRs had positive effect on growth and yield of wheat nevertheless, the effect of chlormequat chloride followed by salicylic acid was greater than jasmonic acid; so that foliar applications of chlormequat chloride, salicylic acid and jasmonic acid were associated with 20.7%, 13.8% and 7.24% increase in grain yield, respectively, under controlled conditions. These values were 18.3%, 12.2% and 8.1% for the field experiment. Such compensatory effects of PGRs could be due to various reasons. Chlormequat chloride can stimulate root growth, reduce transpiration, increase water use efficiency, and prevent chlorophyll destruction. Similarly, SA application may result in stomatal closure, increased WUE, increased chlorophyll content, increased respiratory-pathways and intercellular CO2 concentration, and stimulatory changes in other physiological and biochemical attributes. Jasmonic acid is also essential components for the signaling pathway

  13. Physiological basis of barley yield under near optimal and stress conditions

    Directory of Open Access Journals (Sweden)

    Pržulj Novo

    2004-01-01

    Full Text Available Average barley yield fall below its potential due to incidence of stresses. Water stress is the main environmental factor limiting yield. The component a priori more sensitive to most stresses is the amount of radiation absorbed. The effect of stresses influence on the total amount of radiation absorbed by barley crop during its vegetation and the photosynthetic efficiency of radiation conversion. Growth inhibition is accompanied by reductions in leaf and cell wall extensibility. Grain yield under drought conditions is source limited. Supply of assimilates to the developing inflorescence plays a critical role in establishing final grain number and grain size. Grain weight is negatively affected by drought, high temperature, and any other factors that may reduce grain filling duration and grain filling rate. Awns and glaucousness confer better performance of barley under drought stress conditions. Barley responds with an increased accumulation of a number of proteins when subjected to different stress inducing cell dehydration. Screening techniques that are able to identify desirable genotypes based on the evaluation of physiological traits related to stress evasion and stress resistance maybe useful in breeding barley for resistance to stress, particularly drought stress. Crop management and breeding can reduce the incidence of stress on yield. The effect of these practices is sustained by an understanding of their physiology. In this paper the physiological basis of the processes determining barley yield and the incidence of stresses on photosynthetic metabolism that determine grain yield of barley is discussed. .

  14. Improving Crop Yield and Nutrient Use Efficiency via Biofertilization-A Global Meta-analysis.

    Science.gov (United States)

    Schütz, Lukas; Gattinger, Andreas; Meier, Matthias; Müller, Adrian; Boller, Thomas; Mäder, Paul; Mathimaran, Natarajan

    2017-01-01

    The application of microbial inoculants (biofertilizers) is a promising technology for future sustainable farming systems in view of rapidly decreasing phosphorus stocks and the need to more efficiently use available nitrogen (N). Various microbial taxa are currently used as biofertilizers, based on their capacity to access nutrients from fertilizers and soil stocks, to fix atmospheric nitrogen, to improve water uptake or to act as biocontrol agents. Despite the existence of a considerable knowledge on effects of specific taxa of biofertilizers, a comprehensive quantitative assessment of the performance of biofertilizers with different traits such as phosphorus solubilization and N fixation applied to various crops at a global scale is missing. We conducted a meta-analysis to quantify benefits of biofertilizers in terms of yield increase, nitrogen and phosphorus use efficiency, based on 171 peer reviewed publications that met eligibility criteria. Major findings are: (i) the superiority of biofertilizer performance in dry climates over other climatic regions (yield response: dry climate +20.0 ± 1.7%, tropical climate +14.9 ± 1.2%, oceanic climate +10.0 ± 3.7%, continental climate +8.5 ± 2.4%); (ii) meta-regression analyses revealed that yield response due to biofertilizer application was generally small at low soil P levels; efficacy increased along higher soil P levels in the order arbuscular mycorrhizal fungi (AMF), P solubilizers, and N fixers; (iii) meta-regressions showed that the success of inoculation with AMF was greater at low organic matter content and at neutral pH. Our comprehensive analysis provides a basis and guidance for proper choice and application of biofertilizers.

  15. Water and radiation use efficiencies of transplanted rice (Oryza sativa L.) at different plant densities and irrigation regimes under semi-arid environment

    International Nuclear Information System (INIS)

    Ahmad, S.; Ali, H.; Shad, S.A.; Zia-ul-Haq, M.; Ahmad, A.; Maqsood, M.; Khan, M.B.; Mehmood, S.; Hussain, A.

    2008-01-01

    Growth and yield of rice (Oryza sativa L.), in response to plant densities and irrigation (optimum to stress) were analyzed in terms of interception and utilization of photo-synthetically active radiation (PAR) and water use efficiency (WUE). The amount of PAR intercepted and cumulative evapotranspiration (ET) by each treatment was estimated from the measured leaf area index. The relationships between total dry matter grain yield and accumulated intercepted PAR and cumulative ET were linear. Yield differences among the treatments were attributed to the amount of PAR intercepted and water transpired their efficiencies of utilization or both. The fraction of intercepted radiation and WUE was significantly affected by the plant densities and various irrigation regimes, while, radiation utilization efficiency (RUE) and water use efficiency (WUE) for TDM varied from 1.15 g MJ-1 to 1.36 g MJ-1 and 22.6 kg per ha mm-1 to 24.3 kg per ha mm-1 during both the seasons

  16. Inverse gradients in leaf wax δD and δ13C values along grass blades of Miscanthus sinensis: implications for leaf wax reproduction and plant physiology.

    Science.gov (United States)

    Gao, Li; Huang, Yongsong

    2013-06-01

    Compound specific hydrogen and carbon isotopic ratios of higher plant leaf waxes have been extensively used in paleoclimate and paleoenvironmental reconstructions. However, studies so far have focused on the comparison of leaf wax isotopic differences in bulk leaf samples between different plant species. We sampled three different varieties of tall grasses (Miscanthus sinensis) in six segments from base to tip and determined hydrogen and carbon isotopic ratios of leaf waxes, as well as hydrogen and oxygen isotopic ratios of leaf water samples. We found an increasing, base-to-tip hydrogen isotopic gradient along the grass blades that can probably be attributed to active leaf wax regeneration over the growth season. Carbon isotopic ratios, on the other hand, show opposite trends to hydrogen isotopic ratios along the grass blades, which may reflect different photosynthetic efficiencies at different blade locales.

  17. Exogenously applied plant growth regulators enhance the morpho-physiological growth and yield of rice under high temperature

    Directory of Open Access Journals (Sweden)

    Shah Fahad

    2016-08-01

    Full Text Available A two-year experiment was conducted to ascertain the effects of exogenously applied plant growth regulators (PGR on rice growth and yield attributes under high day (HDT and high night temperature (HNT. Two rice cultivars (IR-64 and Huanghuazhan were subjected to temperature treatments in controlled growth chambers and four different combinations of ascorbic acid (Vc, alpha-tocopherol (Ve, brassinosteroids (Br, methyl jasmonates (MeJA and triazoles (Tr were applied. High temperature severely affected rice morphology, and also reduced leaf area, above- and below-ground biomass, photosynthesis, and water use efficiency, while increased the leaf water potential of both rice cultivars. Grain yield and its related attributes except number of panicles, were reduced under high temperature. The HDT posed more negative effects on rice physiological attributes, while HNT was more detrimental for grain formation and yield. The Huanghuazhan performed better than IR-64 under high temperature stress with better growth and higher grain yield. Exogenous application of PGRs was helpful in alleviating the adverse effects of high temperature. Among PGR combinations, the Vc+Ve+MejA+Br was the most effective treatment for both cultivars under high temperature stress. The highest grain production by Vc+Ve+MejA+Br treated plants was due to enhanced photosynthesis, spikelet fertility and grain filling, which compensated the adversities of high temperature stress. Taken together, these results will be of worth for further understanding the adaptation and survival mechanisms of rice to high temperature and will assist in developing heat-resistant rice germplasm in future.

  18. Comparison the effect of organic and chemical fertilizers on yield and essential oil percentage of Basil (Ocimum basilicum L.

    Directory of Open Access Journals (Sweden)

    S.M.K. Tahami

    2016-04-01

    Full Text Available In order to have a sustainable agriculture it is necessary to use environmental friendly inputs to improve ecological aspects of environment. Basil (Ocimum basilicum L. is a medicinal and vegetable crop which is cultivated in different parts of the world. An experiment was conducted at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in year 2009. A complete randomized block design with six treatments, and three replications was used. The treatments were: control (no fertilizer, cow manure, sheep manure, hen manure, vermin-compost and NPK fertilizers. Results showed that all studied organic manures were high in measured characters in compare with chemical fertilizer. The highest plant height, leaf yield, fresh and dry matter were obtained at vermicompost. Treatments have no significant affect on Essential oil percentage. The highest essential oil yield was obtained in cow manure treatments. Third cut and the first cut had the maximum and the minimum of leaf yield, fresh and dry shoot yield, respectively. Essential oil percentage in the first cut was significantly more than other cuts, but essential oil yield, were the highest in third cut because this cut produced highest leaf yield. There was no significant difference between chemical fertilizers and control treatment in all characters except green area index and fresh and dry leaf weight in a plant.

  19. Evaluation of Forage Yield and Important Agronomic Indices of Corn Affected by Intercropping Systems with Peanut and Nitrogen Rates

    Directory of Open Access Journals (Sweden)

    M Nabati nasaz

    2016-07-01

    Full Text Available Introduction Multiple cropping such as intercropping plays an important role in agriculture because of maximizing beneficial interactions. Intercropping of legumes and cereals is an old practice in tropical agriculture that dates back to ancient civilization. Maize-legume intercrops could substantially increase forage quantity and quality and decrease requirement for protein supplements (Ahmad et al., 2008. Intercropping of cereals and legumes is important for development of sustainable food production systems. This may be due to some of the potential benefits in intercropping systems such as high productivity and profitability, improvement of soil fertility through the additional supply of N by fixation and excretion from the component legume, efficient use of resources, reducing damage caused by pests, diseases and weeds and improvement of forage quality (Ahmad et al., 2008; Fernandez-Aparicio et al., 2007; Lithourgidis et al., 2006. The main advantage of intercropping is more efficient utilization of the available resources and the increased productivity compared with each sole crop of the mixture. Therefore, this experiment was conducted to evaluate agronomic characteristics of corn and Land equivalent ratio (LER under intercropping with peanut and different rates of nitrogen. Materials and methods In order to evaluate the forage yield and important agronomic indices of corn (Zea mays L. affected by intercropping systems with peanut and different nitrogen rates, this experiment was performed in the experimental field of agricultural and natural resource research center of Guilan province, Rasht, Iran, during 2013-14 cropping season as a split plot arrangement in randomized complete block design with three replications. Nitrogen rates, including of zero, 100, 200 and 300 kg per hectare as main plot and sole cropping of corn and peanut (Arachis hypogaea L., intercropping systems including of intercropping corn and peanut at ratio of 1:1, 2

  20. Fertigation for improved water use efficiency and crop yield

    International Nuclear Information System (INIS)

    Al-Wabel, M.I.; Al-Jaloud, A.A.; Hussain, G.; Karimulla, S.

    2002-01-01

    A greenhouse experiment was carried out at the Al-Muzahmiya Research Station, King Abdulaziz City for Science and Technology, Riyadh, to evaluate the effect of fertigation on cucumber yield. Five labelled N ( 15 N) treatments namely a control, soil application (120 mg N L -1 ), N-1 (60 mg N L -1 ), N-2 (120 mg N L -1 ) and N-3 (180 mg N L -1 ) were tried for their effect on greenhouse cucumber yield. A cucumber cultivar (Figaro F-1) was sown as test crop. The experiment was carried out during the period from April to July, 1997. The mean fresh fruit cucumber yield ranged between 7.73 to 33.74 t ha -1 . Highest yield was obtained with the labelled N application of 180 mg L -1 . The mean ranges for the different elements in the plant leaves were 1.33- 2.70% (N), 0.364-0.515% (P) and 1.57-3.82% (K). Whereas, in the plant shoot these ranges were 1.26-2.42% (N), 0.28-0.49% (P) and 4.74-9.45% (K). The mean content of the different elements in the cucumber fruit was 2.15-3.70% (N), 0.47-0.73% (P) and 4.40-5.23% (K). The soil salinity varied between 2.23-4.66 dS m -1 in the top soil (0-20 cm depth) and 0.95-2.62 dS m -1 in the sub-surface (20-40 cm depth) soil. The application did not affect significantly the soil salinity and was found well below the hazardous limit for most crops. The evolution of the other elements was different.. For example, elements such as Ca, P and K showed an increase while Na showed a decrease, whereas the Mg content did not respond with increasing N application. The soil moisture ranged between 8.06-9.15% (0-20 cm depth) and 5.51-9.36% (20-40 cm depth) and did not show any effect of N application. The nitrogen use efficiency (NUE) varied between 72.70 to 129.53 kg kg -1 N in the different N treatments. The mean 15 N a.e. ranged from 0.010 to 0.844% (leaves), 0.058 to 0.855% (shoots), 0.044 to 0.747 (roots) and 0.07 to 0.823 % (fruits). In conclusion, the mean highest yield of cucumber as fresh fruit was 33.74 t ha -1 , obtained with 180 mg N L

  1. Correlação entre composição das fôlhas e produção, e tamanho de frutos, em laranjeira baianinha Correlation between leaf composition and yields, and orange fruit sizes, as affected by fertilization

    Directory of Open Access Journals (Sweden)

    J. Romano Gallo

    1966-01-01

    significant: 1. Leaf nitrogen with yields (weights, r = 0.35**. 2. Leaf nitrogen with number of fruits, r = 0.40**. 3. Leaf nitrogen with fruit sizes (average weights, r = - 0.36**. 4. Leaf potassium with fruit sizes (average weights, r = 0.52**. 5. Leaf calcium with fruit yields (weights, r = 0.51**. Leaf phosphorus was not significantly correlated with yields (weights, number of fruits, or fruit sizes.

  2. insect antagonistic bio-inoculants for natural control of leaf-mining

    African Journals Online (AJOL)

    ACSS

    to planting, if leaf mining damages and associated yield losses in French beans are to ... inoculants, constituent ainsi de grands potentiels agents protecteurs de cultures et pourraient être utilisés de ... in sustaining food security and soil health.

  3. A sensitive hydrogen peroxide sensor based on leaf-like silver

    International Nuclear Information System (INIS)

    Meng, Zuchao; Zhang, Mingyin; Zhang, Hongfang; Zheng, Jianbin

    2014-01-01

    A novel non-enzymatic hydrogen peroxide sensor based on leaf-like silver was constructed. The leaf-like silver was synthesized on the surface of L-cysteine (L-cys) by electrodeposition. Scanning electron microscopy and electrochemical techniques were used to characterize the leaf-like silver nanoparticles. The sensor showed high electrocatalytic activity towards the reduction of hydrogen peroxide. A wide linear range of 2.5–1.5 mM with a low detection limit of 0.7 µM was obtained. Excellent electrocatalytic activity, large surface-to-volume ratio and efficient electron transport properties of leaf-like silver have enabled stable and highly sensitive performance for the non-enzymatic hydrogen peroxide sensor. (paper)

  4. Ideotype population exploration: growth, photosynthesis, and yield components at different planting densities in winter oilseed rape (Brassica napus L.).

    Science.gov (United States)

    Ma, Ni; Yuan, Jinzhan; Li, Ming; Li, Jun; Zhang, Liyan; Liu, Lixin; Naeem, Muhammad Shahbaz; Zhang, Chunlei

    2014-01-01

    Rapeseed is one of the most important edible oil crops in the world and the seed yield has lagged behind the increasing demand driven by population growth. Winter oilseed rape (Brassica napus L.) is widely cultivated with relatively low yield in China, so it is necessary to find the strategies to improve the expression of yield potential. Planting density has great effects on seed yield of crops. Hence, field experiments were conducted in Wuhan in the Yangtze River basin with one conventional variety (Zhongshuang 11, ZS11) and one hybrid variety (Huayouza 9, HYZ9) at five planting densities (27.0×10(4), 37.5×10(4), 48.0×10(4), 58.5×10(4), 69.0×10(4) plants ha(-1)) during 2010-2012 to investigate the yield components. The physiological traits for high-yield and normal-yield populations were measured during 2011-2013. Our results indicated that planting densities of 58.5×10(4) plants ha(-1) in ZS11 and 48.0×10(4) plants ha(-1) in HYZ9 have significantly higher yield compared with the density of 27.0×10(4) plants ha(-1) for both varieties. The ideal silique numbers for ZS11 and HYZ9 were ∼0.9×10(4) (n m(-2)) and ∼1×10(4) (n m(-2)), respectively, and ideal primary branches for ZS11 and HYZ9 were ∼250 (n m(-2)) and ∼300 (n m(-2)), respectively. The highest leaf area index (LAI) and silique wall area index (SAI) was ∼5.0 and 7.0, respectively. Moreover, higher leaf net photosynthetic rate (Pn) and water use efficiency (WUE) were observed in the high-yield populations. A significantly higher level of silique wall photosynthesis and rapid dry matter accumulation were supposed to result in the maximum seed yield. Our results suggest that increasing the planting density within certain range is a feasible approach for higher seed yield in winter rapeseed in China.

  5. Partial root zone drying (PRD) sustains yield of potatoes (Solanum tuberosum L.) at reduced water supply

    DEFF Research Database (Denmark)

    Shahnazari, Ali; Andersen, Mathias Neumann; Liu, Fulai

    2008-01-01

    Partial root zone drying (PRD) is a new water-saving irrigation strategy being tested in many crop species. Until now it has not been investigated in potatoes (Solanum tuberosum L.). A field experiment on sandy soil in Denmark was conducted under a mobile rainout shelter to study effects of two...... subsurface drip irrigation treatments ((1) Full Irrigation (FI) receiving 100% of evaporative demand; and (2) PRD receiving 70% water of FI) on potato yield, tuber size, leaf water relations and irrigation water use efficiency (IWUE). The PRD treatment was started just after the end of tuber initiation...... for two months during tuber bulking and maturing stage and was shifted from one side to the other side of the plants every 5-10 days when FI plants had used 20-25 mm. Compared to FI plants, stomatal conductance was generally lower in the PRD-treated plants, whereas leaf water potential tended to be lower...

  6. Effects of Methanol Spraying on Qualitative traits, Yield and Yield Components of Soybean (Glycine max L. under Drought Stress Conditions

    Directory of Open Access Journals (Sweden)

    J Esazadeh Panjali Kharabasi

    2017-12-01

    Full Text Available Introduction Soybean (Glycin max L. is one of the most important oilseed crops in the world. It can provide oil and vegetable protein suitable for feeding humans as well as animals. The productivity Increasing of this crop in Iran has been the subject of continuous investigation over the past few years. It is well known that adequate water supply is considered as a very important factor to affect the accumulation of dry matter in the plant as well as vegetative growth of most crops. Irrigation is an important factor affecting soybean growth and yield and its related components. Exposing soybean plants to soil moisture stress at any phase of its life cycle may lead to a detrimental effect on growth, yield and its components. The methanol spraying can lead to increase in yield, expediting in maturity and reduction in drought stress impacts and water requirement of crops. Material and Methods The experiment was conducted as split plots based on randomized complete block design with three replications at the Research Farm, Faculty of Agriculture of Moghan, Iran, in 2011. Treatments included three levels of drought stress as follows irrigation after, 40 (control, 55 and 70 percentage of available soil moisture depletion as main plots, and four levels of methanol spraying including 0 (control, 7, 21 and 35 volumetric percentage as sub plots. The studied traits were included plant height, leaf area, number of pod and seed per plant, 1000 seed weight, biological and seed yield, stomatal conductance and proline contents. Statistical analysis was carried out using SAS version 9.1 software. Significant difference was set at p ≤ 0.05 by using Duncan’s multiple range test. Results and Discussion The results showed that the plant height, leaf area, number of pod and seed per plant, 1000 seed weight, biological and seed yield, stomatal conductance and proline contents as well as number of leaf per plant significantly affected by drought stress and methanol

  7. [Comparison of potential yield and resource utilization efficiency of main food crops in three provinces of Northeast China under climate change].

    Science.gov (United States)

    Wang, Xiao-yu; Yang, Xiao-guang; Sun, Shuang; Xie, Wen-juan

    2015-10-01

    Based on the daily data of 65 meteorological stations from 1961 to 2010 and the crop phenology data in the potential cultivation zones of thermophilic and chimonophilous crops in Northeast China, the crop potential yields were calculated through step-by-step correction method. The spatio-temporal distribution of the crop potential yields at different levels was analyzed. And then we quantified the limitations of temperature and precipitation on the crop potential yields and compared the differences in the climatic resource utilization efficiency. The results showed that the thermal potential yields of six crops (including maize, rice, spring wheat, sorghum, millet and soybean) during the period 1961-2010 deceased from west to east. The climatic potential yields of the five crops (spring wheat not included) were higher in the south than in the north. The potential yield loss rate due to temperature limitations of the six crops presented a spatial distribution pattern and was higher in the east than in the west. Among the six main crops, the yield potential loss rate due to temperature limitation of the soybean was the highest (51%), and those of the other crops fluctuated within the range of 33%-41%. The potential yield loss rate due to water limitation had an obvious regional difference, and was high in Songnen Plain and Changbai Mountains. The potential yield loss rate of spring wheat was the highest (50%), and those of the other four rainfed crops fluctuated within the range of 8%-10%. The solar energy utilization efficiency of the six main crops ranged from 0.9% to 2.7%, in the order of maize> sorghum>rice>millet>spring wheat>soybean. The precipitation utilization efficiency of the maize, sorghum, spring wheat, millet and soybean under rainfed conditions ranged from 8 to 35 kg . hm-2 . mm-1, in the order of maize>sorghum>spring wheat>millet>soybean. In those areas with lower efficiency of solar energy utilization and precipitation utilization, such as Changbai

  8. Foliar K application delays leaf senescence of winter rape-seed (Brassica napus L.) under waterlogging

    Institute of Scientific and Technical Information of China (English)

    Lin Wan; Chao Hu; Chang Chen; Liyan Zhang; Ni Ma; Chunlei Zhang

    2017-01-01

    To better understand waterlogging effect on leaf senescence in winter rapseed (Brassica napus L.) during flowering stage, experiments were designed to explore foliar K application influences on adverse effects of waterlogging stress. Winter rapeseed was sprayed with K after waterlogging at initial flowering stage. Results indicated that waterlog-ging significantly decreased leaf net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr). It also declined maximum quantum yield of PS II (Fv/Fm), quantum yield of electron transport (ΦPS II) and pho-tochemical quenching (qP), but increased leaf non-photochemical quenching (NPQ) and minimal fluorescence (Fo). Interestingly, exogenous application of K significantly alleviated waterlogging-induced photosynthesis inhibition. Foliar K application increased RuBisCO activation, chlorophyll and soluble protein contents, while significantly decreased MDA con-tent under waterlogging stress. Moreover, K supplementation improved accumulation of K+, Ca2+, Mg2+, N, Zn2+, Mn2+, Fe2+ in leaves. In general, foliar K application is effective in alleviating deleterious effects of waterlogging stress and delays leaf senescence of winter rapeseed.

  9. Non-destructive linear model for leaf area estimation in Vernonia ferruginea Less

    Directory of Open Access Journals (Sweden)

    MC. Souza

    Full Text Available Leaf area estimation is an important biometrical trait for evaluating leaf development and plant growth in field and pot experiments. We developed a non-destructive model to estimate the leaf area (LA of Vernonia ferruginea using the length (L and width (W leaf dimensions. Different combinations of linear equations were obtained from L, L2, W, W2, LW and L2W2. The linear regressions using the product of LW dimensions were more efficient to estimate the LA of V. ferruginea than models based on a single dimension (L, W, L2 or W2. Therefore, the linear regression “LA=0.463+0.676WL” provided the most accurate estimate of V. ferruginea leaf area. Validation of the selected model showed that the correlation between real measured leaf area and estimated leaf area was very high.

  10. Effect of pig manure on nutrient composition, growth and yield of Okra

    African Journals Online (AJOL)

    Five rates of manure, 0,2.5,5.0,7.5, and 10.0t/ha and NPK (15-15-15) fertilizer } at 200kg/ha were compared as to their effects on leaf nutrient composition, growth and pod yield of okra. Pig manure increased okra leaf nutrient N,P,K Ca and Mg contents, and the nutrients increased with application of manure. NPK fertilizer ...

  11. Leaf rust of cultivated barley: pathology and control.

    Science.gov (United States)

    Park, Robert F; Golegaonkar, Prashant G; Derevnina, Lida; Sandhu, Karanjeet S; Karaoglu, Haydar; Elmansour, Huda M; Dracatos, Peter M; Singh, Davinder

    2015-01-01

    Leaf rust of barley is caused by the macrocyclic, heteroecious rust pathogen Puccinia hordei, with aecia reported from selected species of the genera Ornithogalum, Leopoldia, and Dipcadi, and uredinia and telia occurring on Hordeum vulgare, H. vulgare ssp. spontaneum, Hordeum bulbosum, and Hordeum murinum, on which distinct parasitic specialization occurs. Although Puccinia hordei is sporadic in its occurrence, it is probably the most common and widely distributed rust disease of barley. Leaf rust has increased in importance in recent decades in temperate barley-growing regions, presumably because of more intensive agricultural practices. Although total crop loss does not occur, under epidemic conditions yield reductions of up to 62% have been reported in susceptible varieties. Leaf rust is primarily controlled by the use of resistant cultivars, and, to date, 21 seedling resistance genes and two adult plant resistance (APR) genes have been identified. Virulence has been detected for most seedling resistance genes but is unknown for the APR genes Rph20 and Rph23. Other potentially new sources of APR have been reported, and additivity has been described for some of these resistances. Approaches to achieving durable resistance to leaf rust in barley are discussed.

  12. Interaction effects of water salinity and hydroponic growth medium on eggplant yield, water-use efficiency, and evapotranspiration

    Directory of Open Access Journals (Sweden)

    Farnoosh Mahjoor

    2016-06-01

    Full Text Available Eggplant (Solanum melongena L. is a plant native to tropical regions of Southeast Asia. The water crisis and drought on the one hand and eggplant greenhouse crop development as one of the most popular fruit vegetables for people on the other hand, led to the need for more research on the use of saline water and water stress to optimize salinity level and their impact on eggplant evapotranspiration and encounter better yield and crop quality. The objective of the present study was to investigate the interactions of water salinity and hydroponic growth medium on qualitative and quantitative properties of eggplant and its water-use efficiency. The study used the factorial experiment based on completely randomized design with three replications of four levels of water salinity (electrical conductivity of 0.8 (control, 2.5, 5, and 7 dS m−1 and three growth media (cocopeat, perlite, and a 50–50 mixture of the two by volume. Total yield, yield components, evapotranspiration, and water-use efficiency were determined during two growing periods, one each in 2012 and 2013. All of these indices decreased significantly as water salinity increased. Water with of 0.8 dS m−1 produced an average eggplant yield of 2510 g per plant in 2012 and 2600 g in 2013. The highest yield was observed in cocopeat. Water with 7 dS m−1 reduced yield to 906 g per plant in 2012 and to 960 g in 2013. Lowest yield was observed in perlite. The highest evapotranspiration values occurred in cocopeat at the lowest salinity in both years. Cocopeat and the cocopeat–perlite mixture were equally good substrates. The mixture significantly improved the quantitative and qualitative properties of eggplant yield.

  13. The narrow-leaf syndrome: a functional and evolutionary approach to the form of fog-harvesting rosette plants.

    Science.gov (United States)

    Martorell, Carlos; Ezcurra, Exequiel

    2007-04-01

    Plants that use fog as an important water-source frequently have a rosette growth habit. The performance of this morphology in relation to fog interception has not been studied. Some first-principles from physics predict that narrow leaves, together with other ancillary traits (large number and high flexibility of leaves, caudices, and/or epiphytism) which constitute the "narrow-leaf syndrome" should increase fog-interception efficiency. This was tested using aluminum models of rosettes that differed in leaf length, width and number and were exposed to artificial fog. The results were validated using seven species of Tillandsia and four species of xerophytic rosettes. The total amount of fog intercepted in rosette plants increased with total leaf area, while narrow leaves maximized interception efficiency (measured as interception per unit area). The number of leaves in the rosettes is physically constrained because wide-leafed plants can only have a few blades. At the limits of this constraint, net fog interception was independent of leaf form, but interception efficiency was maximized by large numbers of narrow leaves. Atmospheric Tillandsia species show the narrow-leaf syndrome. Their fog interception efficiencies were correlated to the ones predicted from aluminum-model data. In the larger xerophytic rosette species, the interception efficiency was greatest in plants showing the narrow-leaf syndrome. The adaptation to fog-harvesting in several narrow-leaved rosettes was tested for evolutionary convergence in 30 xerophytic rosette species using a comparative method. There was a significant evolutionary tendency towards the development of the narrow-leaf syndrome the closer the species grew to areas where fog is frequently available. This study establishes convergence in a very wide group of plants encompassing genera as contrasting as Tillandsia and Agave as a result of their dependence on fog.

  14. Forage yield and nutritive value of Tanzania grass under nitrogen supplies and plant densities

    Directory of Open Access Journals (Sweden)

    Fabrício Paiva de Freitas

    2012-04-01

    Full Text Available The objective of this experiment was to evaluate the nitrogen and plant density influence on the yield, forage dissection and nutritive value of Tanzania grass (Panicum maximum Jacq.. The design was of completely randomized blocks with three replications in a factorial arrangement with four nitrogen levels (0, 80, 160 or 320 kg/ha N and three plant densities (9, 25 or 49 plants/m². The plots were cut at 25 cm from soil level when the canopy reached 95% of light interception. The total dry matter forage yield and dry matter forage yield per harvest increased linearly with the nitrogen fertilization. The leaf and stem yield had the same response. The senesced forage yield was quadratically influenced by the nitrogen. The stems ratio in the morphologic composition was high in the high nitrogen levels and in the low plant densities. The leaf:stem ratio showed high values in this trial, but it was increased in plots without nitrogen and high plant density. The pre-grazing height was reduced with the increase in plant density. The nutritive value was favored by the nitrogen fertilization, which increased the crude protein level and reduced neutral detergent fiber and lignin. These factors increased the leaf and stem in vitro digestibility of organic matter. Nitrogen fertilization increases the forage yield of Tanzania grass under rotational grazing. After the establishment, plant density has little influence on the Tanzania grass yield and its forage dissection. The harvest with 95% light interception improves the structure and nutritive value of Tanzania grass pastures.

  15. A Case Study of Improving Yield Prediction and Sulfur Deficiency Detection Using Optical Sensors and Relationship of Historical Potato Yield with Weather Data in Maine

    Science.gov (United States)

    Sharma, Lakesh K.; Bali, Sukhwinder K.; Dwyer, James D.; Plant, Andrew B.; Bhowmik, Arnab

    2017-01-01

    In Maine, potato yield is consistent, 38 t·ha−1, for last 10 years except 2016 (44 t·ha−1) which confirms that increasing the yield and quality of potatoes with current fertilization practices is difficult; hence, new or improvised agronomic methods are needed to meet with producers and industry requirements. Normalized difference vegetative index (NDVI) sensors have shown promise in regulating N as an in season application; however, using late N may stretch out the maturation stage. The purpose of the research was to test Trimble GreenSeeker® (TGS) and Holland Scientific Crop Circle™ ACS-430 (HCCACS-430) wavebands to predict potato yield, before the second hilling (6–8 leaf stage). Ammonium sulfate, S containing N fertilizer, is not advised to be applied on acidic soils but accounts for 60–70% fertilizer in Maine’s acidic soils; therefore, sensors are used on sulfur deficient site to produce sensor-bound S application guidelines before recommending non-S-bearing N sources. Two study sites investigated for this research include an S deficient site and a regular spot with two kinds of soils. Six N treatments, with both calcium ammonium nitrate and ammonium nitrate, under a randomized complete block design with four replications, were applied at planting. NDVI readings from both sensors were obtained at V8 leaf stages (8 leaf per plant) before the second hilling. Both sensors predict N and S deficiencies with a strong interaction with an average coefficient of correlation (r2) ~45. However, HCCACS-430 was observed to be more virtuous than TGS. The correlation between NDVI (from both sensors) and the potato yield improved using proprietor-proxy leaf area index (PPLAI) from HCCACS-430, e.g., r2 value of TGS at Easton site improve from 48 to 60. Weather data affected marketable potato yield (MPY) significantly from south to north in Maine, especially precipitation variations that could be employed in the N recommendations at planting and in season

  16. Effects of source and sink manipulation on distribution of 14C-assimilate and endogenous hormone contents of high-yield cotton in Xinjiang

    International Nuclear Information System (INIS)

    Luo Honghai; Zhao Ruihai; Li Junhua; Zhang Yali; Zhang Wangfeng

    2011-01-01

    Effects of leaf-cutting and bud-thinning treatment on partitioning of 14 C-assimilate and endogenous hormone contents of source leaf (respective axial leaf and sympodian leaf) during flowering and boll-setting stage in high-yield cotton were studied by using Gossipium hirsutum L. cv. Xinluzao 132 as plant material. Results showed that bud-thinning reduced the peak value of indole-3-acetic acid (IAA) delayed the accumulation of isopenteny ladenime and its riboside (iP + iPA), and decreased the contents of abscisic acid (ABA) zeatin and its riboside (Z + ZR) of source leaf. Thus, the export and partitioning of percentage of 14 C-assimilate in boll was significantly decreased at full bolling and boll opening stages. As a result, both of boll weight and yield in bud-thinning were significantly lower than control. Leaf-cutting significantly improved the content of cytokinins (CTKs) and the distributive percentage of 14 C-assimilates in boll. Furthermore, when leaves were cut 1/4 at anthesis, no differences were found in number of bolls per plant, boll weight and yield compared with control. These results suggested that regulating source-sink relation with key practices of cultivation would be of great importance to super-high and stable yield of cotton, as it would affect the changes of endogenous hormone levels and regulate the distribution of 14 C-assimilate between source and sink. (authors)

  17. Radiation utilization efficiency and the growth of soybeans exposed to ozone: a comparative analysis

    International Nuclear Information System (INIS)

    Leadley, P.W.; Reynolds, J.F.; Flagler, R.; Heagle, A.S.

    1990-01-01

    Effects of ozone (O 3 ) on field-planted soybeans (Glycine max (L.) Merr. ‘Davis’) were examined using a simple crop-growth model that resolves the rate of increase in crop dry weight into the total amount of radiation intercepted by a crop canopy and the efficiency of conversion of this energy into dry matter (ϵ, termed utilization efficiency). The objectives were : (1) to examine the effects of O 3 on light interception and ϵ, and compare these results with a similar study by Unsworth et al. to determine whether the effects of O 3 are consistent from year to year, and (2) to determine whether ϵ is more sensitive to O 3 during reproductive than vegetative growth and whether allocation of aboveground biomass to seed is affected by O 3 . Five O 3 concentrations (seasonal means of 30, 52, 57, 76 and 99 ppb) were maintained in open-top chambers over the growing season. All treatments were irrigated. Leaf, stem and pod weights and leaf area were measured weekly throughout the season. Total incident solar radiation and total radiation transmission through the canopy were measured with tube solarimeters and electronic integrating devices. Increased O 3 concentrations were accompanied by depressed leaf area expansion and earlier leaf senescence, but did not affect total light interception over the entire season. Utilization efficiency (ϵ) was reduced in high O 3 treatments and was the most important factor in the reduction of yield; ϵ for the whole season declined from 0.89 g MJ −1 in the 30-ppb treatment to a low of 0.68 g MJ −1 in the 99-ppb treatment. Efficiencies were higher during reproductive than vegetative growth, but were not more sensitive to O 3 . Seed yield decreased from 450 g m −2 in the 30-ppb treatment to 320 g m −2 in the 99-ppb treatment. Fractional allocation of aboveground dry weight to seed was not affected by O 3 . Reduced ϵ values with increasing O 3 concentrations were consistent with an earlier study by Unsworth et al. however

  18. Final report on the safety assessment of AloeAndongensis Extract, Aloe Andongensis Leaf Juice,aloe Arborescens Leaf Extract, Aloe Arborescens Leaf Juice, Aloe Arborescens Leaf Protoplasts, Aloe Barbadensis Flower Extract, Aloe Barbadensis Leaf, Aloe Barbadensis Leaf Extract, Aloe Barbadensis Leaf Juice,aloe Barbadensis Leaf Polysaccharides, Aloe Barbadensis Leaf Water, Aloe Ferox Leaf Extract, Aloe Ferox Leaf Juice, and Aloe Ferox Leaf Juice Extract.

    Science.gov (United States)

    2007-01-01

    Plant materials derived from the Aloe plant are used as cosmetic ingredients, including Aloe Andongensis Extract, Aloe Andongensis Leaf Juice, Aloe Arborescens Leaf Extract, Aloe Arborescens Leaf Juice, Aloe Arborescens Leaf Protoplasts, Aloe Barbadensis Flower Extract, Aloe Barbadensis Leaf, Aloe Barbadensis Leaf Extract, Aloe Barbadensis Leaf Juice, Aloe Barbadensis Leaf Polysaccharides, Aloe Barbadensis Leaf Water, Aloe Ferox Leaf Extract, Aloe Ferox Leaf Juice, and Aloe Ferox Leaf Juice Extract. These ingredients function primarily as skin-conditioning agents and are included in cosmetics only at low concentrations. The Aloe leaf consists of the pericyclic cells, found just below the plant's skin, and the inner central area of the leaf, i.e., the gel, which is used for cosmetic products. The pericyclic cells produce a bitter, yellow latex containing a number of anthraquinones, phototoxic compounds that are also gastrointestinal irritants responsible for cathartic effects. The gel contains polysaccharides, which can be acetylated, partially acetylated, or not acetylated. An industry established limit for anthraquinones in aloe-derived material for nonmedicinal use is 50 ppm or lower. Aloe-derived ingredients are used in a wide variety of cosmetic product types at concentrations of raw material that are 0.1% or less, although can be as high as 20%. The concentration of Aloe in the raw material also may vary from 100% to a low of 0.0005%. Oral administration of various anthraquinone components results in a rise in their blood concentrations, wide systemic distribution, accumulation in the liver and kidneys, and excretion in urine and feces; polysaccharide components are distributed systemically and metabolized into smaller molecules. aloe-derived material has fungicidal, antimicrobial, and antiviral activities, and has been effective in wound healing and infection treatment in animals. Aloe barbadensis (also known as Aloe vera)-derived ingredients were not toxic

  19. Effect of pre-bloom leaf removal on grape aroma composition and wine sensory profile of Semillon cultivar.

    Science.gov (United States)

    Alessandrini, Massimiliano; Battista, Fabrizio; Panighel, Annarita; Flamini, Riccardo; Tomasi, Diego

    2018-03-01

    Early leaf removal at pre-bloom is an innovative viticultural practice for regulating yield components and improving grape quality. The effects of this technique on vine performance, grape composition and wine sensory profile of Semillon variety were assessed. Pre-bloom leaf removal enhanced canopy porosity, total soluble solids in musts and reduced cluster compactness. This practice had a strong effect on glycoside aroma precursors, in particular by increasing glycoside terpenols and norisoprenoids. Metabolites of linalool were the most responsive to leaf removal. Wine produced from defoliated vines was preferred in tasting trials for its more intense fruity notes and mouthfeel attributes. Pre-bloom leaf removal is a powerful technique for modifying canopy microclimate, vine yield, grape composition and wine quality. The increase of glycoside aroma compounds in treated grapes has potential positive effect in improving the sensory profile of the resulting wines. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  20. Improving Crop Yield and Nutrient Use Efficiency via Biofertilization—A Global Meta-analysis

    Science.gov (United States)

    Schütz, Lukas; Gattinger, Andreas; Meier, Matthias; Müller, Adrian; Boller, Thomas; Mäder, Paul; Mathimaran, Natarajan

    2018-01-01

    The application of microbial inoculants (biofertilizers) is a promising technology for future sustainable farming systems in view of rapidly decreasing phosphorus stocks and the need to more efficiently use available nitrogen (N). Various microbial taxa are currently used as biofertilizers, based on their capacity to access nutrients from fertilizers and soil stocks, to fix atmospheric nitrogen, to improve water uptake or to act as biocontrol agents. Despite the existence of a considerable knowledge on effects of specific taxa of biofertilizers, a comprehensive quantitative assessment of the performance of biofertilizers with different traits such as phosphorus solubilization and N fixation applied to various crops at a global scale is missing. We conducted a meta-analysis to quantify benefits of biofertilizers in terms of yield increase, nitrogen and phosphorus use efficiency, based on 171 peer reviewed publications that met eligibility criteria. Major findings are: (i) the superiority of biofertilizer performance in dry climates over other climatic regions (yield response: dry climate +20.0 ± 1.7%, tropical climate +14.9 ± 1.2%, oceanic climate +10.0 ± 3.7%, continental climate +8.5 ± 2.4%); (ii) meta-regression analyses revealed that yield response due to biofertilizer application was generally small at low soil P levels; efficacy increased along higher soil P levels in the order arbuscular mycorrhizal fungi (AMF), P solubilizers, and N fixers; (iii) meta-regressions showed that the success of inoculation with AMF was greater at low organic matter content and at neutral pH. Our comprehensive analysis provides a basis and guidance for proper choice and application of biofertilizers. PMID:29375594

  1. Improving Crop Yield and Nutrient Use Efficiency via Biofertilization—A Global Meta-analysis

    Directory of Open Access Journals (Sweden)

    Lukas Schütz

    2018-01-01

    Full Text Available The application of microbial inoculants (biofertilizers is a promising technology for future sustainable farming systems in view of rapidly decreasing phosphorus stocks and the need to more efficiently use available nitrogen (N. Various microbial taxa are currently used as biofertilizers, based on their capacity to access nutrients from fertilizers and soil stocks, to fix atmospheric nitrogen, to improve water uptake or to act as biocontrol agents. Despite the existence of a considerable knowledge on effects of specific taxa of biofertilizers, a comprehensive quantitative assessment of the performance of biofertilizers with different traits such as phosphorus solubilization and N fixation applied to various crops at a global scale is missing. We conducted a meta-analysis to quantify benefits of biofertilizers in terms of yield increase, nitrogen and phosphorus use efficiency, based on 171 peer reviewed publications that met eligibility criteria. Major findings are: (i the superiority of biofertilizer performance in dry climates over other climatic regions (yield response: dry climate +20.0 ± 1.7%, tropical climate +14.9 ± 1.2%, oceanic climate +10.0 ± 3.7%, continental climate +8.5 ± 2.4%; (ii meta-regression analyses revealed that yield response due to biofertilizer application was generally small at low soil P levels; efficacy increased along higher soil P levels in the order arbuscular mycorrhizal fungi (AMF, P solubilizers, and N fixers; (iii meta-regressions showed that the success of inoculation with AMF was greater at low organic matter content and at neutral pH. Our comprehensive analysis provides a basis and guidance for proper choice and application of biofertilizers.

  2. Effect of fertilizer application on yield of oil palm

    Directory of Open Access Journals (Sweden)

    Eksomtramage, T.

    2001-11-01

    Full Text Available The effects of fertilizer application rates on leaf nutrient contents and yield of oil palm were investigated at the Agricultural and Technological College Plantation in Trang province during May 1998 - June 2001. A five-year-old oil palm plantation, planted on the Na Tham soil series (Fine loamy, mixed, isohyperthermic Oxic Plinthudults with spacing 9x9x9 m, was selected for study. A randomized complete block designwith three replications with 20 palms/replication was used. The treatments included six different rates of fertilizer application. The rates of fertilizer were as follows: T1 (farmer practice, T2 (40% of application rate in T4, T3 (70% of application rate in T4, T4 (urea 2,750 g/plant; triple super phosphate 1,500 g/plant; potassium chloride 4,000 g/plant; kieserite 1,000 g/plant; borate 80 g/plant, T5 (130% of application rate in T4 and T6 (170% of application rate in T4. The high leaf nutrient contents of N, P and K at the range of 2.6-2.8%, 0.16-0.18% and 1.13-1.18%, respectively, were found in the high nutrient application rate treatments (T5, T6. However, the amounts of leaf Ca and Mg in T5 and T6 decreased from 0.75-0.80% and 0.33- 0.37% at the beginning of experiment to 0.65-0.70% and 0.22-0.24%, respectively, at the end of the experiment. Small increases of leaf sulphur and boron up to about 0.20-0.22% and 16-19 mg/kg were also found in the high rate of fertilizer treatments. Accumulated fresh fruit bunch yield (FFB increased according to increasing rate of fertilizer application. Accumulated FFB yield of 268.4 kg/plant in the low fertilizer rate (T1 (farmer practice and 278.8 kg/plant in T2 were found compared with the highest yield of 370.2 kg/plant in the highest fertilizer application treatment (T6 for the 3 years experiment. Regarding the economic return, the medium rate of fertilizer application (T3 which achieved an accumulated FFB yield of 338.0 kg/ plant gave the highest profit with the VCR (Value: Cost ratio of 2.53.

  3. Leaf absorbance and photosynthesis

    Science.gov (United States)

    Schurer, Kees

    1994-01-01

    The absorption spectrum of a leaf is often thought to contain some clues to the photosynthetic action spectrum of chlorophyll. Of course, absorption of photons is needed for photosynthesis, but the reverse, photosynthesis when there is absorption, is not necessarily true. As a check on the existence of absorption limits we measured spectra for a few different leaves. Two techniques for measuring absorption have been used, viz. the separate determination of the diffuse reflectance and the diffuse transmittance with the leaf at a port of an integrating sphere and the direct determination of the non-absorbed fraction with the leaf in the sphere. In a cross-check both methods yielded the same results for the absorption spectrum. The spectrum of a Fuchsia leaf, covering the short-wave region from 350 to 2500 nm, shows a high absorption in UV, blue and red, the well known dip in the green and a steep fall-off at 700 nm. Absorption drops to virtually zero in the near infrared, with subsequent absorptions, corresponding to the water absorption bands. In more detailed spectra, taken at 5 nm intervals with a 5 nm bandwidth, differences in chlorophyll content show in the different depths of the dip around 550 nm and in a small shift of the absorption edge at 700 nm. Spectra for Geranium (Pelargonium zonale) and Hibiscus (with a higher chlorophyll content) show that the upper limit for photosynthesis can not be much above 700 nm. No evidence, however, is to be seen of a lower limit for photosynthesis and, in fact, some experiments down to 300 nm still did not show a decrease of the absorption although it is well recognized that no photosynthesis results with 300 nm wavelengths.

  4. Effects of Watering and Nitrogen Fertilization on Yield and Water and Nitrogen Use Efficiency of Cropping Oil Sunflower

    Directory of Open Access Journals (Sweden)

    TAN Jian-xin

    2015-10-01

    Full Text Available The field experiment with split-plot design was conducted to study the effects of the interaction of water and nitrogen fertilization on the growth and yield of oil sunflower, water and nitrogen use efficiency of cropping oil sunflower. This experiment set three irrigation rate treatments, including high irrigation treatment (5 250 m3·hm-2, middle irrigation treatment (3 750 m3·hm-2, low irrigation treatment (2 250 m3·hm-2, and four nitrogen application rate treatments, covering no nitrogen fertilization treatment (0 kg·hm-2, low nitrogen application treatment (120 kg·hm-2, middle nitrogen application treatment (240 kg·hm-2 and high nitrogen application treatment (360 kg·hm-2. The results showed that the nitrogen absorption and nitrogen use efficiency of cropping oil sunflower increased as the irrigation rate increased. With the nitrogen application rate increased, the yield of cropping oil sunflower was increased when the nitrogen application rate was 0~240 kg·hm-2, but beyond the 240 kg·hm-2, there was no significant increase. With the irrigation rate increased, the water consumption amount of cropping oil sunflower increased all the time, but the water use efficiency increased first, and hen decreased. Besides there was no significant difference between 240 kg·hm-2 and 360 kg·hm-2 treatment. Under our experiment condition, during the cropping oil sunflower growth period, when the irrigation rate was 5 250 m3·hm-2 (high irrigation rate and the nitrogen ertilization was 360 m3·hm-2 (high nitrogen application rate, the yield of cropping oil sunflower was 3 598 kg·hm-2. When the irrigation rate was 3 750 m3·hm-2 (middle irrigation rate and the nitrogen fertilization was 240 m3·hm-2 (middle nitrogen application rate, the yield was 3 518 kg·hm-2, with the yield components similar with the high irrigation rate and high nitrogen application rate treatment. Considering various factors, middle irrigation rate and middle nitrogen

  5. How Investor Structure Influences the Yield, Information Dissemination Efficiency, and Liquidity

    Directory of Open Access Journals (Sweden)

    Hongli Che

    2014-01-01

    Full Text Available This essay focuses on the investor structure of the stock index futures market and uses agent-based computational finance method to discuss how the volume-synchronized probability of informed trading (VPIN affects market absolute yield, information dissemination efficiency, and liquidity with different ratios of informed traders in the market. The result shows that the higher the proportion of informed traders is, the more the volatility of the market is. Furthermore, the result indicates that when the proportion of informed traders in the stock index futures market accounts for 1/3-1/2, the transparency and liquidity of the market will be better.

  6. [Effects of tobacco garlic crop rotation and intercropping on tobacco yield and rhizosphere soil phosphorus fractions].

    Science.gov (United States)

    Tang, Biao; Zhang, Xi-zhou; Yang, Xian-bin

    2015-07-01

    A field plot experiment was conducted to investigate the tobacco yield and different forms of soil phosphorus under tobacco garlic crop rotation and intercropping patterns. The results showed that compared with tobacco monoculture, the tobacco yield and proportion of middle/high class of tobacco leaves to total leaves were significantly increased in tobacco garlic crop rotation and intercropping, and the rhizosphere soil available phosphorus contents were 1.3 and 1.7 times as high as that of tobacco monoculture at mature stage of lower leaf. For the inorganic phosphorus in rhizosphere and non-rhizosphere soil in different treatments, the contents of O-P and Fe-P were the highest, followed by Ca2-P and Al-P, and Ca8-P and Ca10-P were the lowest. Compared with tobacco monoculture and tobacco garlic crop intercropping, the Ca2-P concentration in rhizosphere soil under tobacco garlic crop rotation at mature stage of upper leaf, the Ca8-P concentration at mature stage of lower leaf, and the Ca10-P concentration at mature stage of middle leaf were lowest. The Al-P concentrations under tobacco garlic crop rotation and intercropping were 1.6 and 1.9 times, and 1.2 and 1.9 times as much as that under tobacco monoculture in rhizosphere soil at mature stages of lower leaf and middle leaf, respectively. The O-P concentrations in rhizosphere soil under tobacco garlic crop rotation and intercropping were significantly lower than that under tobacco monoculture. Compared with tobacco garlic crop intercropping, the tobacco garlic crop rotation could better improve tobacco yield and the proportion of high and middle class leaf by activating O-P, Ca10-P and resistant organic phosphorus in soil.

  7. Effect of drought stress on leaf soluble sugar content, leaf rolling index and relative water content of proso millet (Panicum miliaceum L. genotypes

    Directory of Open Access Journals (Sweden)

    mohamad javad seghatol eslami

    2009-06-01

    Full Text Available With respect to water shortage in arid and semi- arid regions, the study about drought stress effects on crop plants and selection of resistance cultivars, are among the most important goals in the agricultural researches. In order to examine drought stress effects on millet, an experiment was conducted in Birjand and Sarbisheh, simultaneously. In this experiment, five irrigation treatments (well-watered, drought stress in vegetative stage, in ear emergence stage, in seed filling stage and in vegetative and seed filling stage and five proso millet genotypes (Native, K-C-M.2, K-C-M.4, K-C-M.6 and K-C-M.9 were compared in a split plot design along with three replications. Drought stress increased grain protein content, leaf rolling index and soluble sugars concentration and decreased seed germination and leaf RWC. Although seed protein content and germination percentage of genotypes were not significantly different, there were some differences among leaf rolling index, RWC and soluble sugar content of these genotypes. The results of this study indicated that leaf sugar content, RWC and leaf rolling index can not be considered as the only parameters for selection of high yield genotypes. Therefore, it is recommended that some other factors should also be used apart from the above mentioned ones.

  8. Breed of cow and herd productivity affect milk nutrient recovery in curd, and cheese yield, efficiency and daily production.

    Science.gov (United States)

    Stocco, G; Cipolat-Gotet, C; Gasparotto, V; Cecchinato, A; Bittante, G

    2018-02-01

    Little is known about cheese-making efficiency at the individual cow level, so our objective was to study the effects of herd productivity, individual herd within productivity class and breed of cow within herd by producing, then analyzing, 508 model cheeses from the milk of 508 cows of six different breeds reared in 41 multi-breed herds classified into two productivity classes (high v. low). For each cow we obtained six milk composition traits; four milk nutrient (fat, protein, solids and energy) recovery traits (REC) in curd; three actual % cheese yield traits (%CY); two theoretical %CYs (fresh cheese and cheese solids) calculated from milk composition; two overall cheese-making efficiencies (% ratio of actual to theoretical %CYs); daily milk yield (dMY); and three actual daily cheese yield traits (dCY). The aforementioned phenotypes were analyzed using a mixed model which included the fixed effects of herd productivity, parity, days in milk (DIM) and breed; the random effects were the water bath, vat, herd and residual. Cows reared in high-productivity herds yielded more milk with higher nutrient contents and more cheese per day, had greater theoretical %CY, and lower cheese-making efficiency than low-productivity herds, but there were no differences between them in terms of REC traits. Individual herd within productivity class was an intermediate source of total variation in REC, %CY and efficiency traits (10.0% to 17.2%), and a major source of variation in milk yield and dCY traits (43.1% to 46.3%). Parity of cows was an important source of variation for productivity traits, whereas DIM affected almost all traits. Breed within herd greatly affected all traits. Holsteins produced more milk, but Brown Swiss cows produced milk with higher actual and theoretical %CYs and cheese-making efficiency, so that the two large-framed breeds had the same dCY. Compared with the two large-framed breeds, the small Jersey cows produced much less milk, but with greater actual

  9. Gold leaf counter electrodes for dye-sensitized solar cells

    Science.gov (United States)

    Shimada, Kazuhiro; Toyoda, Takeshi

    2018-03-01

    In this study, a gold leaf 100 nm thin film is used as the counter electrode in dye-sensitized solar cells. The traditional method of hammering gold foil to obtain a thin gold leaf, which requires only small amounts of gold, was employed. The gold leaf was then attached to the substrate using an adhesive to produce the gold electrode. The proposed approach for fabricating counter electrodes is demonstrated to be facile and cost-effective, as opposed to existing techniques. Compared with electrodes prepared with gold foil and sputtered gold, the gold leaf counter electrode demonstrates higher catalytic activity with a cobalt-complex electrolyte and higher cell efficiency. The origin of the improved performance was investigated by surface morphology examination (scanning electron microscopy), various electrochemical analyses (cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy), and crystalline analysis (X-ray diffractometry).

  10. Yielding ability and weed suppression of potato and wheat under organic nitrogen management

    NARCIS (Netherlands)

    Delden, van A.

    2001-01-01

    Keywords: chickweed, early growth, leaf area expansion, light interception, light use efficiency, manure, mineralisation, modelling, organic farming, organic matter, soil nitrogen content , Solanum tuberosum L., specific leaf area , Stellaria media

  11. Effects of combination of leaf resources on competition in container mosquito larvae.

    Science.gov (United States)

    Reiskind, M H; Zarrabi, A A; Lounibos, L P

    2012-08-01

    Resource diversity is critical to fitness in many insect species, and may determine the coexistence of competitive species and the function of ecosystems. Plant material provides the nutritional base for numerous aquatic systems, yet the consequences of diversity of plant material have not been studied in aquatic container systems important for the production of mosquitoes. To address how diversity in leaf detritus affects container-inhabiting mosquitoes, we examined how leaf species affect competition between two container inhabiting mosquito larvae, Aedes aegypti and Aedes albopictus, that co-occur in many parts of the world. We tested the hypotheses that leaf species changes the outcome of intra- and interspecific competition between these mosquito species, and that combinations of leaf species affect competition in a manner not predictable based upon the response to each leaf species alone (i.e. the response to leaf combinations is non-additive). We find support for our first hypothesis that leaf species can affect competition, evidence that, in general, leaf combination alters competitive interactions, and no support that leaf combination impacts interspecific competition differently than intraspecific competition. We conclude that combinations of leaves increase mosquito production non-additively such that combinations of leaves act synergistically, in general, and result in higher total yield of adult mosquitoes in most cases, although certain leaf combinations for A. albopictus are antagonistic. We also conclude that leaf diversity does not have a different effect on interspecific competition between A. aegypti and A. albopictus, relative to intraspecific competition for each mosquito.

  12. Yield performance and leaf nutrient levels of coffee cultivars under different plant densities Produtividade e níveis foliares de nutrientes em cultivares de café sob diferentes populações de plantas

    Directory of Open Access Journals (Sweden)

    Edison Martins Paulo

    2010-12-01

    Full Text Available Coffee (Coffea Arabica L. plantations using adapted cultivars to regional environmental conditions with optimal plant population density and adequate nutrition are expected to show high yield responses. The triennial production and leaf macronutrient concentrations of four coffee cultivars were studied under different plant population densities. Catuaí Amarelo (IAC 47, Obatã (IAC 1669-20, Acaiá (IAC 474-19 and Icatu Amarelo (IAC 2944 were planted in densities of 2,500; 5,000; 7,519; and 10,000 plants ha-1 with one plant per hole and two plants per hole in the 2,500 plant ha-1. Plants were homogeneously fertilized without liming. As the population density increased the triennial coffee productivity increased, the yield per plant decreased, and leaf concentrations of phosphorus (P, potassium (K and sulfur (S increased. Coffee plants under dense systems presented equal or higher leaf macronutrient concentrations compared to the plants under conventional population. Taller cultivars presented the highest nutrient concentration values, and Obatã, a dwarf cultivar, the lowest values. Higher coffee yields and lower leaf P, Ca and S concentrations were observed in plots with one plant compared to the plots with two plants. In general, the coffee cultivars had leaf N and S concentrations above the reference limits reported in the literature, but leaf concentrations of other macronutrients were within adequate ranges.Cultivares de cafeeiro (Coffea Arabica L. adaptadas às regiões de cultivo, com população de plantas otimizada e adequado estado nutricional são premissas para a obtenção de produções elevadas de café. Estudou-se a produção trienal de café e o teor foliar de macronutrientes de cultivares de cafeeiro em função das densidades de plantio. Foram utilizados os cultivares Catuaí Amarelo (IAC 47, Obatã (IAC 1669-20, Acaiá (IAC 474-19 e Icatu Amarelo (IAC 2944 nas populações de 2.500 plantas ha-1 com duas plantas por cova; e, 5

  13. Assessment of leaf/stem ratio in wheat straw feedstock and impact on enzymatic conversion

    DEFF Research Database (Denmark)

    Zhang, Heng; Fangel, Jonatan Ulrik; Willats, William George Tycho

    2014-01-01

    . By preparing samples of various leaf-to-stem (L/S) ratios, we found shifting conversion behavior as processing parameters were modified. Increasing the enzyme dosage, pretreatment temperature and pretreatment time all significantly improved conversion rates in samples with more than 50% leaf content, whereas...... less impact was observed on samples with less than 50% leaf content. Enzyme affinity, desorption and readsorption with leaf and stem fractions may affect the sugar yield in wheat straw saccharification. The data suggest that the L/S ratio is an important parameter when adjusting or optimizing...... conversion processes and additionally in feedstock breeding. Furthermore, this highlights the need for rapid techniques for determining L/S ratio in wheat straw harvests. The CoMPP data on specific carbohydrates and leaf pectin highlight carbohydrate epitopes that may be useful as markers in the development...

  14. Simulating the yield impacts of organ-level quantitative trait loci associated with drought response in maize: a "gene-to-phenotype" modeling approach.

    Science.gov (United States)

    Chenu, Karine; Chapman, Scott C; Tardieu, François; McLean, Greg; Welcker, Claude; Hammer, Graeme L

    2009-12-01

    Under drought, substantial genotype-environment (G x E) interactions impede breeding progress for yield. Identifying genetic controls associated with yield response is confounded by poor genetic correlations across testing environments. Part of this problem is related to our inability to account for the interplay of genetic controls, physiological traits, and environmental conditions throughout the crop cycle. We propose a modeling approach to bridge this "gene-to-phenotype" gap. For maize under drought, we simulated the impact of quantitative trait loci (QTL) controlling two key processes (leaf and silk elongation) that influence crop growth, water use, and grain yield. Substantial G x E interaction for yield was simulated for hypothetical recombinant inbred lines (RILs) across different seasonal patterns of drought. QTL that accelerated leaf elongation caused an increase in crop leaf area and yield in well-watered or preflowering water deficit conditions, but a reduction in yield under terminal stresses (as such "leafy" genotypes prematurely exhausted the water supply). The QTL impact on yield was substantially enhanced by including pleiotropic effects of these QTL on silk elongation and on consequent grain set. The simulations obtained illustrated the difficulty of interpreting the genetic control of yield for genotypes influenced only by the additive effects of QTL associated with leaf and silk growth. The results highlight the potential of integrative simulation modeling for gene-to-phenotype prediction and for exploiting G x E interactions for complex traits such as drought tolerance.

  15. Are GM Crops for Yield and Resilience Possible?

    Science.gov (United States)

    Paul, Matthew J; Nuccio, Michael L; Basu, Shib Sankar

    2018-01-01

    Crop yield improvements need to accelerate to avoid future food insecurity. Outside Europe, genetically modified (GM) crops for herbicide- and insect-resistance have been transformative in agriculture; other traits have also come to market. However, GM of yield potential and stress resilience has yet to impact on food security. Genes have been identified for yield such as grain number, size, leaf growth, resource allocation, and signaling for drought tolerance, but there is only one commercialized drought-tolerant GM variety. For GM and genome editing to impact on yield and resilience there is a need to understand yield-determining processes in a cell and developmental context combined with evaluation in the grower environment. We highlight a sugar signaling mechanism as a paradigm for this approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Effect of planting density and cutting frequency on forage and grain yields of kochia (Kochia scoparia under saline water irrigation

    Directory of Open Access Journals (Sweden)

    mseou ziyaeii

    2009-06-01

    Full Text Available AField experiment was conducted at Research Farms of Center of Excellence for Special Crops, Ferdowsi University of Mashhad, Mashhad, Iran, in 2006 to evaluate the effect of planting density on forage and grain yield of kochia (Kochia scoparia. Experimental design was a randomized complete block with split-plot arrangement of treatments,with three replications, where different planting densities (10, 20, 30 and 40 plant m-2 were assigned to main plots and number of cutting (including a single cutting, two cutting and no cutting i.e. allowing the crop to grow until maturity allocated to sub-plots. At each harvest date (cutting the biological yield, leaf and stem dry weight, plant height, number of branches and the individual plant biomass were measured. Grain yield and thousand seed weight were also determined at the end of growing season. Result showed the highest biological yield and leaf and stem dry weights for kochia obtaind at 30 plant m-2. The total biomass, leaf and stem dry weights, plant height, number of branches were greater for the first cutting as compared to the second cutting. Planting density and cutting number interacted to affect the leaf dry weight. At physiological maturity stage there were no significant differences among planting densities for plant height and number of branches. The best planting density, in terms of biomass production and leaf and stem dry weight, was found as 30 plant m-2, while for grain production a planting density of 20 plant m-2 could be recommended. Key words: Kochia, planting density, sward, biological yield, grain production.

  17. Optimal balance of water use efficiency and leaf construction cost with a link to the drought threshold of the desert steppe ecotone in northern China.

    Science.gov (United States)

    Wei, Haixia; Luo, Tianxiang; Wu, Bo

    2016-09-01

    In arid environments, a high nitrogen content per leaf area (Narea) induced by drought can enhance water use efficiency (WUE) of photosynthesis, but may also lead to high leaf construction cost (CC). Our aim was to investigate how maximizing Narea could balance WUE and CC in an arid-adapted, widespread species along a rainfall gradient, and how such a process may be related to the drought threshold of the desert-steppe ecotone in northern China. Along rainfall gradients with a moisture index (MI) of 0·17-0·41 in northern China and the northern Tibetan Plateau, we measured leaf traits and stand variables including specific leaf area (SLA), nitrogen content relative to leaf mass and area (Nmass, Narea) and construction cost (CCmass, CCarea), δ(13)C (indicator of WUE), leaf area index (LAI) and foliage N-pool across populations of Artemisia ordosica In samples from northern China, a continuous increase of Narea with decreasing MI was achieved by a higher Nmass and constant SLA (reduced LAI and constant N-pool) in high-rainfall areas (MI > 0·29), but by a lower SLA and Nmass (reduced LAI and N-pool) in low-rainfall areas (MI ≤ 0·29). While δ(13)C, CCmass and CCarea continuously increased with decreasing MI, the low-rainfall group had higher Narea and δ(13)C at a given CCarea, compared with the high-rainfall group. Similar patterns were also found in additional data for the same species in the northern Tibetan Plateau. The observed drought threshold where MI = 0·29 corresponded well to the zonal boundary between typical and desert steppes in northern China. Our data indicated that below a climatic drought threshold, drought-resistant plants tend to maximize their intrinsic WUE through increased Narea at a given CCarea, which suggests a linkage between leaf functional traits and arid vegetation zonation. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please

  18. Impact of nitrogen rates on growth, yield and radiation use efficiency of maize under varying environments

    International Nuclear Information System (INIS)

    Khaliq, T.; Ahmad, A.; Hussain, A.

    2008-01-01

    Growth, yield and radiation use efficiency (RUE) of hybrid maize, in response to different nitrogen rates (150, 200, 250, 300, 350 kg ha/sub -1/ were analyzed for three different locations (Faisalabad, Sargodha and Sahiwal) in Punjab, Pakistan during 2004 and 2005. The results depicted a large yearly variations mainly attributed to more rainfall and incidence of solar radiation in 2005. Maize hybrids respond differently for all variable under study, at all sites except IPAR and radiation use efficiency 919 at different locations. Similar types of differences were noted in GGR and Final TOM. Increasing nitrogen rates had significant effects on CGR, final TOM and grain yield and RUE. The intercepted PAR, RUE/sub TDM/ and RUE/sub Gy/ were significantly affected by hybrid potential and nitrogen application rates. On an average RUE/sub TDM/ varied from 2.45 to 2.73 g MJ/sup -1/ at different locations, while RUE/sub Gy/ was recorded 1.12, 1.14 and 1.03 for Faisalabad, Sargodha and Sahiwal, respectively. Total dry matter and grain yield of different treatments was linearly related to IPAR at all location and the common regression (R/sup 2/) accounted for 94, 68, and 80 % for TDM and 64, 34, and 95% for grain yield at the Faisalabad, Sargodha and sahiwal, respectively. It was concluded that planting of hybrid Bemasal-202 with 300 kg N ha/sup -1/ is the best recommendation for semi-arid areas of Pakistan. (author)

  19. On the air cleansing efficiency of an extended green wall: a CFD analysis of mechanistic details of transport processes.

    Science.gov (United States)

    Joshi, Saumitra V; Ghosh, Sat

    2014-11-21

    The detrimental impact of rising air pollution levels in urban landscapes has become conspicuous over the last decade, particularly in developing countries. This novel numerical study quantifies the cleansing efficiency of green façades draped with a copiously growing tropical creeper Vernonia elaeagnifolia. Turbulent transport of SO2 to the leaf boundary layer and subsequent diffusion across stomatal pores into the mesophyllic cells is modeled at the micro level, including its ionic dissociation in the leaf׳s interior. A SEM analysis indicates stomatal dimensions and density. Whilst previous studies have used either spatially averaged equations or resistance models, a spatially discretized computational approach is adopted in this study. The resulting concentration distribution is used to calculate the deposition velocity on stomatal pores, which is then extrapolated over the entire façade to yield bulk pollutant removal rates. A deposition velocity of 1.53mms(-1) and 0.72mms(-1) is obtained for open and closed pores respectively, with removal rates equal to 1.11×10(-6)s(-1) and 1.05×10(-6)s(-1) for dry and humid weather respectively. Sensitivity studies on the removal rate are carried out based on humidity, stomatal aperture and leaf temperature. The removal rate dependence on the Leaf Area Index (LAI) is also investigated. It is inferred from simulations that vegetated façades are efficient at mitigation of residual pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Effect of cotton leaf-curl virus on the yield-components and fibre properties of cotton genotypes under varying plant spacing and nitrogen fertilizer

    International Nuclear Information System (INIS)

    Ahmad, S.; Hayat, K.; Ashraf, F.; Sadiq, M.A.

    2008-01-01

    Cotton leaf-curl virus (CLCu VB. Wala strain) is one of the major biotic constraints of cotton production in Punjab. Development of resistant cotton genotype is the most feasible, economical and effective method to combat this hazardous problem, but so far no resistant genotype has been reported. Therefore, the objective of this study was to compare yield and yield-components and fiber traits of different genotypes/varieties under different plant spacing and nitrogen fertilizer as a management strategy to cope with this viral disease. Field experiment was conducted during 2006-07 to evaluate the effect of genotype, plant spacing and nitrogen fertilizer on cotton. Five genotypes (MNH-786, MNH-789, MNH- 6070, CIM- 496, and BH-160), three plant-spacings (15, 30 and 45 cm) and three nitrogen fertilizer-levels (6.5, 8.6 and 11 bags Urea / ha) were studied. Results showed that significant differences exist for plant height, no. of bolls/m/sup -2/, seed-cotton yield (kg/ha) due to genotype, interaction of genotype with plant spacing and nitrogen fertilizer level. Whereas boll weight, ginning out-turn, staple length and fiber fineness were not affected significantly by the plant spacing and nitrogen fertilizer, the effect due to genotype was significant for these traits. CLCuV infestation varied significantly with genotypes, while all other factors, i.e., plant spacing and nitrogen fertilizers, have non-significant effect. As the major objective of cotton cultivation is production of lint for the country and seed- cotton yield for the farmers, it is noted that genotypes grown in narrow plant-spacing (15 cm) and higher nitrogen fertilizer level (11.0 bags of urea/ha) produced maximum seed-cotton yield under higher CLCu V infestation in case of CIM-496, MNH-789 and BH-I60, while the new strain MNH-6070 gave maximum yield under 30cm plant-spacing and 8.6 bags of urea/ha has the 2.3% CLCu V infestation was observed in this variety. From the present study, it is concluded that

  1. Seasonal Canopy Temperatures for Normal and Okra Leaf Cotton under Variable Irrigation in the Field

    Directory of Open Access Journals (Sweden)

    James R. Mahan

    2016-11-01

    Full Text Available Temperature affects a number of physiological factors in plants and is related to water use, yield and quality in many crop species. Seasonal canopy temperature, measured with infrared thermometers, is often used in conjunction with environmental factors (e.g., air temperature, humidity, solar radiation to assess crop stress and management actions in cotton. Normal and okra leaf shapes in cotton have been associated with differences in water use and canopy temperature. The okra leaf shape in cotton is generally expected to result in lower water use and lower canopy temperatures, relative to normal leaf, under water deficits. In this study canopy temperatures were monitored in okra and normal leaf varieties for a growing season at four irrigation levels. Differences in canopy temperature (<2 °C were measured between the two leaf shapes. As irrigation levels increased, canopy temperature differences between the leaf shapes declined. At the lowest irrigation level, when differences in sensible energy exchanges due to the okra leaf shape would be enhanced, the canopy temperature of the okra leaf was warmer than the normal leaf. This suggests that varietal differences that are not related to leaf shape may have more than compensated for leaf shape differences in the canopy temperature.

  2. Comparative role of neem seed extract, moringa leaf extract and imidacloprid in the management of wheat aphids in relation to yield losses in Pakistan.

    Science.gov (United States)

    Shah, Farhan Mahmood; Razaq, Muhammad; Ali, Abid; Han, Peng; Chen, Julian

    2017-01-01

    Wheat being staple food of Pakistan is constantly attacked by major wheat aphid species, Schizaphis graminum (R.), Rhopalosiphum padi (L.) and Sitobion avenae (F.). Due to concern on synthetic chemical use in wheat, it is imperative to search for alternative environment- and human- friendly control measures such as botanical pesticides. In the present study, we evaluated the comparative role of neem seed extract (NSE), moringa leaf extract (MLE) and imidacloprid (I) in the management of the aphid as well as the yield losses parameters in late planted wheat fields. Imidacloprid reduced significantly aphids infestation compared to the other treatments, hence resulting in higher yield, particularly when applied with MLE. The percentages of yield increase in I+MLE treated plots over the control were 19.15-81.89% for grains per spike, 5.33-37.62% for thousand grain weight and 27.59-61.12% for yield kg/ha. NSE was the second most effective control measure in suppressing aphid population, but the yield protected by NSE treatment over the control was comparable to that by imidacloprid. Population densities of coccinellids and syrphids in the plots treated with NSE-2 were higher than those treated with imidacloprid in two out of three experiments during 2013-14. Low predator density in imidacloprid-treated plots was attributed to the lower availability of prey aphids. The efficacy of NSE against aphids varied depending on degree of synchronization among the application timing, the activity of aphids, crop variety and environmental conditions. Despite that, we suggested NSE to be a promising alternative botanical insecticide compared to the most commonly recommended imidiacloprid. Further studies should consider the side effects of biopesticides on non-target organisms in order to provide better management practices in the field.

  3. Incorporation of resistance to angular leaf spot and bean common ...

    African Journals Online (AJOL)

    Luseko

    2013-07-03

    Jul 3, 2013 ... Angular leaf spot (ALS) caused by the fungus Pseudocercospora griseola and Bean common mosaic and necrosis virus (BCMV/BCMNV) are important diseases of common bean in Tanzania that can cause severe yield reduction when uncontrolled. This study was conducted to incorporate resistant genes ...

  4. Incorporation of resistance to angular leaf spot and bean common ...

    African Journals Online (AJOL)

    Angular leaf spot (ALS) caused by the fungus Pseudocercospora griseola and Bean common mosaic and necrosis virus (BCMV/BCMNV) are important diseases of common bean in Tanzania that can cause severe yield reduction when uncontrolled. This study was conducted to incorporate resistant genes for ALS and ...

  5. Intraspecific Variation in Wood Anatomical, Hydraulic, and Foliar Traits in Ten European Beech Provenances Differing in Growth Yield

    Science.gov (United States)

    Hajek, Peter; Kurjak, Daniel; von Wühlisch, Georg; Delzon, Sylvain; Schuldt, Bernhard

    2016-01-01

    In angiosperms, many studies have described the inter-specific variability of hydraulic-related traits and little is known at the intra-specific level. This information is however mandatory to assess the adaptive capacities of tree populations in the context of increasing drought frequency and severity. Ten 20-year old European beech (Fagus sylvatica L.) provenances representing the entire distribution range throughout Europe and differing significantly in aboveground biomass increment (ABI) by a factor of up to four were investigated for branch wood anatomical, hydraulic, and foliar traits in a provenance trial located in Northern Europe. We quantified to which extend xylem hydraulic and leaf traits are under genetic control and tested whether the xylem hydraulic properties (hydraulic efficiency and safety) trades off with yield and wood anatomical and leaf traits. Our results showed that only three out of 22 investigated ecophysiological traits showed significant genetic differentiations between provenances, namely vessel density (VD), the xylem pressure causing 88% loss of hydraulic conductance and mean leaf size. Depending of the ecophysiological traits measured, genetic differentiation between populations explained 0–14% of total phenotypic variation, while intra-population variability was higher than inter-population variability. Most wood anatomical traits and some foliar traits were additionally related to the climate of provenance origin. The lumen to sapwood area ratio, vessel diameter, theoretical specific conductivity and theoretical leaf-specific conductivity as well as the C:N-ratio increased with climatic aridity at the place of origin while the carbon isotope signature (δ13C) decreased. Contrary to our assumption, none of the wood anatomical traits were related to embolism resistance but were strong determinants of hydraulic efficiency. Although ABI was associated with both VD and δ13C, both hydraulic efficiency and embolism resistance were

  6. Occurrence of barley leaf disease and control strategies in Denmark

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Ørum, Jens Erik; Heick, Thies Marten

    Barley (Hordeum vulgare) is one of the major crops in Denmark and of special importance for malting and for pig feed. In 2016, the crop was grown covering a total area of 700,000 ha; approximately 25% of arable area in Denmark. To ensure high yield of around 60 dt ha-1, disease-tolerant cultivars...... have proven to be quite effective against all leaf diseases, aside from brown rust and mildew. Denmark has a national record system for pesticide usages. All farmers upload their fungicide use by crop, creating a good basis for assessing the differences in use pattern across different regions...... and fungicide treatments are required. Each year, barley cultivars are assessed for susceptibility towards leaf diseases in national observation plots. The most predominant fungal leaf diseases in Denmark are barley scald (Rhynchosporium secalis), net blotch (Pyrenophora teres), brown rust (Puccinia hordei...

  7. Peach leaf responses to soil and cement dust pollution.

    Science.gov (United States)

    Maletsika, Persefoni A; Nanos, George D; Stavroulakis, George G

    2015-10-01

    Dust pollution can negatively affect plant productivity in hot, dry and with high irradiance areas during summer. Soil or cement dust were applied on peach trees growing in a Mediterranean area with the above climatic characteristics. Soil and cement dust accumulation onto the leaves decreased the photosynthetically active radiation (PAR) available to the leaves without causing any shade effect. Soil and mainly cement dust deposition onto the leaves decreased stomatal conductance, photosynthetic and transpiration rates, and water use efficiency due possibly to stomatal blockage and other leaf cellular effects. In early autumn, rain events removed soil dust and leaf functions partly recovered, while cement dust created a crust partially remaining onto the leaves and causing more permanent stress. Leaf characteristics were differentially affected by the two dusts studied due to their different hydraulic properties. Leaf total chlorophyll decreased and total phenol content increased with dust accumulation late in the summer compared to control leaves due to intense oxidative stress. The two dusts did not cause serious metal imbalances to the leaves, except of lower leaf K content.

  8. Morphological traits and yield of red clover (Trifolium pratense L. genotypes with varying inflorescence length

    Directory of Open Access Journals (Sweden)

    Tadeusz Zając

    2013-12-01

    Full Text Available Two red clover breeding strains with elongated flower heads, developed by one of the authors (H.Góral, were studied for forage and seed yield and compared to the standard cultivar 'Nike'. In addition, six morphological shoot traits were measured and their interrelations were computed. The leaf area index (LAI of successive cuts in two harvest years was determined on the basis of shoot density and leaf area of individual shoots. All three genotypes exhibited a high leaf area on shoots and a very high forage productivity. Among the morphological traits only shoot height could be a good selective criterion because it is easily measured, is significantly associated with shoot weight and shoot leaf area and its variation is low. Both strains, particularly the one with longer inflorescences belong to short-lived red clover forms giving satis factory forage and seed yields in the first harvest year. Depending on the strain the number of seeds per elongated inflorescence in the first harvest year was higher by 92 and 42% compared to that of a standard cultivar.

  9. Increasing yield and nitrogen use efficiency of rice through multiple-split fertilizer application

    International Nuclear Information System (INIS)

    Rallos, R.V.; Rivera, F.G.; Samar, E.D.; Rojales, J.S.; Anida, A.H.

    2015-01-01

    The low availability of nitrogen (N) is one of the most important limiting factors impeding the increase in rice yield among the various factors. Split N fertilizer applications can play an important role in nutrient management strategy that is productive, profitable and environmentally responsible. In this study, the recoveries and efficiencies of a multiple-split N fertilizer application of were determined using 15N labeled fertilizer, in order to provide science-based foundation for the nitrogen management in sustainable rice production. A lysimeter experiment with five treatments in four replications was set-up T0 (control). T1 (45 kg N ha“- “1), T2 (90 kg N ha“- “1), T3 (135 kg N ha“- “1) and T4 (180 kg N ha“- “1). 15N tracer analysis showed that, on average, only 30% of applied N is recovered by the crop following one time basal application. In contrast, higher fertilizer nitrogen use efficiencies (FNUE) (>50%) were observed following multiple-split N application. The result of FNUE also corroborates with the significant increase in rice grain yield. Many crops, however, have different nutrient requirements, therefore as in all fertilization strategies, it is highly recommended that source, rate, time and place of application should be considered in making split fertilization decisions. (author)

  10. Dryland maize yields and water use efficiency in response to tillage/crop stubble and nutrient management practices in China

    NARCIS (Netherlands)

    Wang, X.B.; Dai, K.; Zhang, D.; Zhang, X.; Wang, Y.; Zhao, Q.; Cai, D.X.; Hoogmoed, W.B.; Oenema, O.

    2011-01-01

    Rainfed crop production in northern China is constrained by low and variable rainfall. This study explored the effects of tillage/crop residue and nutrient management practices on maize (Zea mays L.) yield, water use efficiency (WUE), and N agronomic use efficiency (NAE) at Shouyang Dryland Farming

  11. Effects of mowing utilization on forage yield and quality in five oat ...

    African Journals Online (AJOL)

    ONOS

    2010-01-25

    Jan 25, 2010 ... The effects of harvest treatment, variety and their interaction on hay yield (HY), crude protein yields (CPY), stem/leaf ratio (S/L ratio), fresh/dry ratio(F/D ratio), crude protein content. (CP), crude fat content (CF), crude ash content (CA) and acid detergent fibre content (ADF) of oat forage were analyzed with ...

  12. A Production Efficiency Model-Based Method for Satellite Estimates of Corn and Soybean Yields in the Midwestern US

    Directory of Open Access Journals (Sweden)

    Andrew E. Suyker

    2013-11-01

    Full Text Available Remote sensing techniques that provide synoptic and repetitive observations over large geographic areas have become increasingly important in studying the role of agriculture in global carbon cycles. However, it is still challenging to model crop yields based on remotely sensed data due to the variation in radiation use efficiency (RUE across crop types and the effects of spatial heterogeneity. In this paper, we propose a production efficiency model-based method to estimate corn and soybean yields with MODerate Resolution Imaging Spectroradiometer (MODIS data by explicitly handling the following two issues: (1 field-measured RUE values for corn and soybean are applied to relatively pure pixels instead of the biome-wide RUE value prescribed in the MODIS vegetation productivity product (MOD17; and (2 contributions to productivity from vegetation other than crops in mixed pixels are deducted at the level of MODIS resolution. Our estimated yields statistically correlate with the national survey data for rainfed counties in the Midwestern US with low errors for both corn (R2 = 0.77; RMSE = 0.89 MT/ha and soybeans (R2 = 0.66; RMSE = 0.38 MT/ha. Because the proposed algorithm does not require any retrospective analysis that constructs empirical relationships between the reported yields and remotely sensed data, it could monitor crop yields over large areas.

  13. Supplementary material from "Increased SBPase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions"

    NARCIS (Netherlands)

    Driever, S.M.; Simkin, Andrew J.; Alotaibi, Saqer; Fisk, Stuart J.; Madgwick, Pippa J.; Sparks, Caroline A.; Jones, Huw D.; Lawson, Tracy; Parry, Martin A.J.; Raines, Christine A.

    2017-01-01

    To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf

  14. Microencapsulation of maqui (Aristotelia chilensis Molina Stuntz leaf extracts to preserve and control antioxidant properties

    Directory of Open Access Journals (Sweden)

    Leslie Vidal J

    2013-03-01

    Full Text Available Microencapsulation technology is an alternative to stabilize stress factors and protect food ingredients or additives, which include environmentally sensitive bioactive principles in protective matrices to increase their functionality and life span. The objective of this research was to study conditions to obtain microcapsules with antioxidant capacity from a maqui (Aristotelia chilensis [Molina] Stuntz, Elaeocarpaceae leaf extract by emulsification and subsequent retention after microencapsulation. Microcapsules were produced by water-in-oil emulsion (W/O using a phase of the aqueous maqui leaf extract and gum arabic, and a liquid vaseline phase. Maqui leaf extract antioxidant capacity was 99.66% compared with the aqueous phase of the emulsion at 94.38 and 93.06% for 5% and 15% gum arabic, respectively. The mean yield of maqui leaf extract microencapsulation with 5% gum arabic varied between 38 and 48%, whereas with 15% gum arabic it was 39%. Once the antioxidant microcapsules were formed, mean extract antioxidant capacity ranged between 30 and 35%. Both yields responded similarly to changes in gum arabic concentrations (5% and 15% in the aqueous phase of the emulsion; 5% concentration produced a microcapsule size from 1.0 to 10 urn. Maqui leaf extracts with high phenolic compound levels, which can be stabilized and protected by the microencapsulation process, produce new natural preservative systems as compared with their synthetic counterparts.

  15. Effect of Different Level of Water Stress and Nitrogen Fertilizer on Yield and Yield Components of Barley in Badjgah (Fars province

    Directory of Open Access Journals (Sweden)

    ali asghar ghaemi

    2016-02-01

    Full Text Available Introduction: Barley is very important to feed humans, livestock, medical, industrial uses, especially in fermentation industries. In Iran, barley crop cultivation was nearly 1.4 million hectares withits production of 1.3 million tons in 2003 (2. Barelyis the oldest crops to environmental stresses such as drought and salinity resistance (3.The different barely growth stages with extreme water requirement can benoted in germination stage, stem elongation, heading the production stage, the stage of flowering and seed production. Typically, for spring and autumn barely respectively 3 and 4 to 5 times irrigation is done during the growing season. The barley water requirement over its life is between 4 and 7 thousand cubic meters and 518 liters of water is needed to produce one kilogram of dry matter. Due to limited water resources and low rainfall in Iran, efficient use of water is absolutely essential and the maximum water utilization must be achieved by applying a minimum amount of water in agriculture. One of the ways to increase productivity in agricultural water is deficit irrigation.Deficit irrigation is an optimization strategy for water use efficiency in irrigation.The purpose of this study was to evaluate the simultaneous effect of fertilizer treatments (150, 225 and 75 kg/ ha and water at three different levels (100%, 75% and 50% of crop water requirement at different growth stages on leaf area index, weight fresh and dried herb and plant nitrogen concentration and the effect of irrigation and nitrogen fertilizer on yield, yield components and productivity of water use. Materials and Method: This research was conducted in Shiraz University in fall 2012 to study the effect of interaction of deficit irrigation and nitrogen fertilizer on yield, yield component and water use efficiency and nitrogen concentration in different stages of barley (Bahman species growth. This experiment were evaluated using a randomized complete block design with s

  16. Effects inoculation of mycorhizae species and irrigation levels impacts on growth criteria, yield and water use efficiency of corb (Zea mays L.

    Directory of Open Access Journals (Sweden)

    M.R. Amerian

    2016-05-01

    Full Text Available Water deficiency is one of the most important factors for limiting crop yield in arid and semiarid regions. Symbiosis with a variety of microorganisms in these regions is one of the modern ecological approaches for sustainable agriculture to reduce damages caused by environmental stresses. Symbiotic of arbuscular mycorrhizal fungi (AM with the roots of crops has shown positive effects on agricultural systems. In order to study the effects of inoculation with two species of mycorrhizal fungi and irrigation levels on root growth criteria and water use efficiency of corn, an experiment was performed as split plots based on a complete randomized block design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad during growing season of 2008-2009. Treatments included two mycorhizae inoculation (Glomus mosseae and G. intraradices and control and four irrigation levels (25, 50, 75 and 100% of water requirement. Grain yield, root specific length, the percentage of root colonization and water use efficiency based on grain yield of corn were measured. The results showed that the effect of mycorrhizae inoculation was significant on (p≤0.05 root specific length, grain yield and water use efficiency of corn. Mycorrhizae species had no significant effect on root colonization percentage of corn. Different irrigation levels had significant effect on grain yield, special length root, the percentage of root colonization, and water use efficiency of corn (p≤0.05. Generally, the results showed that mycorrhizae inoculation in water deficiency conditions, can increase the uptake of water and nutrients by developing the root and increasing the absorbing surface. In this way, not only the plant tolerance against the water deficiency increases, but also more yield will be produced for a specific value of water, which means the water use efficiency increases. Furthermore, the use of water will be decreased.

  17. Study on Yield and Yield Components of Wheat Genotypes under Different Moisture Regimes

    Directory of Open Access Journals (Sweden)

    E. Mogtader

    2012-10-01

    Full Text Available In order to study grain yield and yield components of 16 advanced wheat lines under rainfed and supplementary irrigation conditions, this research was conducted in randomized block design with 3 replications at Maragheh Research Station during 2008-09 seasons. Analysis of variance revealed significant differences for date to heading, plant height, 1000 kernel weight, tiller number, spike length, seed number per spike, spikelet number per spike, peduncle length, harvest index, leaf, sheath length and grain yield. Results also showed that the lines No. 4 (91-142 a 61/3/F35.70/MO73//1D13.1/MLT and 16 (Azar2 with 1895 and 1878 Kg/ha, lines No. 4 and 7 (YUMAI13/5/NAI60/3/14.53/ODIN//CI13441 with 2132 and 2285 Kg/ha had highest grain yield under rainfed and supplementary irrigated conditions respectively. Based on results these 16 lines and cultivars were grouped in 4 and 3 distinct classes using Ward’s Method of cluster analysis under rainfed and irrigated conditions. Path analysis indicated that vigor at shooting stage, seed number per spike and HI were positive important traits to select lines for high yielding potential in this study. HI and TKW had also positive effects on grain under supplementary irrigation.

  18. Investigation of Leaf Diseases and Estimation of Chlorophyll Concentration in Seven Barley Varieties Using Fluorescence and Hyperspectral Indices

    Directory of Open Access Journals (Sweden)

    Kang Yu

    2013-12-01

    Full Text Available Leaf diseases, such as powdery mildew and leaf rust, frequently infect barley plants and severely affect the economic value of malting barley. Early detection of barley diseases would facilitate the timely application of fungicides. In a field experiment, we investigated the performance of fluorescence and reflectance indices on (1 detecting barley disease risks when no fungicide is applied and (2 estimating leaf chlorophyll concentration (LCC. Leaf fluorescence and canopy reflectance were weekly measured by a portable fluorescence sensor and spectroradiometer, respectively. Results showed that vegetation indices recorded at canopy level performed well for the early detection of slightly-diseased plants. The combined reflectance index, MCARI/TCARI, yielded the best discrimination between healthy and diseased plants across seven barley varieties. The blue to far-red fluorescence ratio (BFRR_UV and OSAVI were the best fluorescence and reflectance indices for estimating LCC, respectively, yielding R2 of 0.72 and 0.79. Partial least squares (PLS and support vector machines (SVM regression models further improved the use of fluorescence signals for the estimation of LCC, yielding R2 of 0.81 and 0.84, respectively. Our results demonstrate that non-destructive spectral measurements are able to detect mild disease symptoms before significant losses in LCC due to diseases under natural conditions.

  19. Agave Americana Leaf Fibers

    Directory of Open Access Journals (Sweden)

    Ashish Hulle

    2015-02-01

    Full Text Available The growing environmental problems, the problem of waste disposal and the depletion of non-renewable resources have stimulated the use of green materials compatible with the environment to reduce environmental impacts. Therefore, there is a need to design products by using natural resources. Natural fibers seem to be a good alternative since they are abundantly available and there are a number of possibilities to use all the components of a fiber-yielding crop; one such fiber-yielding plant is Agave Americana. The leaves of this plant yield fibers and all the parts of this plant can be utilized in many applications. The “zero-waste” utilization of the plant would enable its production and processing to be translated into a viable and sustainable industry. Agave Americana fibers are characterized by low density, high tenacity and high moisture absorbency in comparison with other leaf fibers. These fibers are long and biodegradable. Therefore, we can look this fiber as a sustainable resource for manufacturing and technical applications. Detailed discussion is carried out on extraction, characterization and applications of Agave Americana fiber in this paper.

  20. Radiation use efficiency of rice under different planting methods and environmental conditions

    International Nuclear Information System (INIS)

    Apakupakul, R.

    1995-01-01

    Radiation use efficiency is an important parameter which has often been used in many crop growth models to estimate total biomass and yield. Studies of the relationships between above-ground biomass and accumulative absorbed photosynthetically active radiation (PARa, MJ/square m) of rice were examined both on-farms and on-station in Phatthalung. Planting methods were wet-sown and transplanted rice for Suphanburi 90 in the 1993 dry season and Chieng in the 1993-94 wet season. Solar radiation of the two growing seasons were calculated from climatic data. The objectives of this experiment were (1) to know the pattern of relationship between above-ground biomass and accumulative absorbed PAR of rice cultivars grown in South Thailand, (2) to compare the radiation use efficiency of rice cultivars under different planting methods and (3) to obtain the primary data for rice growth modelling in the southern climate. Results presented that only the duration of first growing period up to stem elongation in both cultivars, above-ground biomass and leaf area index were higher in wet-sown than in transplanted rice. Relationship between above-ground biomass accumulation through growing period and accumulative absorbed PAR was in positive linear regression with R*[2)0.85. Erect leaf of Suphanburi 90 had a radiation use efficiency (RUE, g/MJ) higher than non-erect leaf of Chieng. A problem of weed infestation in wet-sown rice in both cultivars had an effect on the RUE which were highly significant lower than transplanted rice. The Rue of wet-sown and transplanted rice were 2.77 and 3.20 g/MJ, respectively for Suphanburi 90, 2.13 and 2.67 g/MJ for Chieng. These results suggest that when dealing with radiation use efficiency in the rice growth modelling the differences of cultivars and planting methods should be taken into consideration

  1. Evaluation of the Effect of Rotation and Application Rate of Nitrogen on Yield, Yield Components and Nitrogen Efficiency Indexes in wheat

    Directory of Open Access Journals (Sweden)

    R Nasri

    2016-02-01

    seeding rate of 200 kg ha-1. Soil samples were collected after harvest of each crop from 0 to 30 cm and 31 to 60 cm soil depths using a soil auger. Wheat grain yield (according to 14% moisture obtained by harvesting the central area of 3 in 10 m in each plot. Yield components were determined from two randomly selected areas (2m2 within each plot. Plant samples collected at harvest were separated into grain and straw and oven-dried at 60˚C for 72hr. Biomass and grain sub samples analyzed for total N content using a micro-Kjeldahl digestion with sulfuric acid. The terminology of N efficiency parameters was considered according to Delogu et al, (11 and Lopez-Bellido & Lopez-Bellido, (22, Rahimizadeh et al. (30, Limon-Ortega et al. (20 methods. Results and Discussion The results showed that there were highly significant differences (P ≤ 0.01 in forage yield. There were also significant differences (P ≤ 0.05 in total dry weight, protein content and protein yield between treatments. Perko varieties produced higher fresh and dry matter yield with 69,586 (kg ha-1 and 7147 (kg ha-1, respectively compared to other varieties. Buko varieties showed greater protein percentage with 23.36 compared to the rest of the varieties. The highest and lowest grain yield, with 8345, and 4491 (kg ha-1 were obtained for Buko; wheat rotation and fallow, wheat rotation, respectively. The highest and lowest nitrogen uptake was obtained for Buko; wheat and clover, wheat rotation, respectively. The differences between the rotations were significant for various agronomic nitrogen efficiency. The rotation of oilseed radish and wheat showed greater nitrogen economic performance with 36.20 kg ha-1. By increasing nitrogen rate agronomic performance decreased with the exception in fallow- wheat. Physiological efficiency of nitrogen in fallow-wheat rotation was more than 39 (kg kg-1 of nitrogen. The maximum efficiency of nitrogen recovery was obtained for oilseed radish: wheat and Perko PVH; wheat

  2. Agrobacterium-mediated genetic transformation of Pogostemon cablin (Blanco) Benth. Using leaf explants: bactericidal effect of leaf extracts and counteracting strategies.

    Science.gov (United States)

    Paul, Anamika; Bakshi, Souvika; Sahoo, Debee Prasad; Kalita, Mohan Chandra; Sahoo, Lingaraj

    2012-04-01

    An optimized protocol for Agrobacterium tumefaciens-mediated transformation of patchouli using leaf disk explants is reported. In vitro antibacterial activity of leaf extracts of the plants revealed Agrobacterium sensitivity to the extracts. Fluorometric assay of bacterial cell viability indicated dose-dependent cytotoxic activity of callus extract against Agrobacterium cells. Addition of 0.1% Tween 20 and 2 g/l L-glutamine to Agrobacterium infection medium counteracted the bactericidal effect and significantly increased the T-DNA delivery to explants. A short preculture of explants for 2 days followed by infection with Agrobacterium in medium containing 150 μM of acetosyringone were found essential for efficient T-DNA delivery. Cocultivation for 3 days at 22 °C in conjunction with other optimized factors resulted in maximum T-DNA delivery. The Agrobacterium-mediated transformation of leaf disk explants were found significantly related to physiological age of the explants, age and origin of the of the donor plant. Leaf explants from second node of the 3-month-old in vivo plants showed highest transformation efficiency (94.3%) revealed by transient GUS expression assay. Plants selected on medium containing 20 mg/l kanamycin showed stable GUS expression in leaves and stem. The elongated shoots readily developed roots on kanamycin-free rooting medium and on transfer to soil, plants were successfully established. Polymerase chain reaction (PCR) and reverse-transcriptase PCR analysis in putative plants confirmed their transgenic nature. The established transformation method should provide new opportunities for the genetic improvement of patchouli for desirable trait.

  3. Photosynthesis efficiency for different wavelengths; Fotosynthese-efficiency bij verschillende golflengten

    Energy Technology Data Exchange (ETDEWEB)

    Snel, J.F.H.; Meinen, E.; Bruins, M.A.; Van Ieperen, W.; Hogewoning, S.W.; Marcelis, L.F.M. [Wageningen UR Glastuinbouw, Wageningen (Netherlands)

    2012-04-15

    LED lighting has recently been introduced into Dutch horticulture. LED development so far indicates that in the near future LED's will be more energy efficient than high pressure sodium lamps. Crop light interception and photosynthesis efficiency are wavelength dependent. Therefore, LED colours for maximum crop photosynthesis, growth and development should be identified. Wageningen UR has investigated light interception and photosynthesis at different wavelengths for tomato, cucumber and rose. Measuring protocols and equipment were developed for leaf photosynthesis measurements in the laboratory and in greenhouses. A crop simulation model was used for up-scaling the leaf level results to crop level photosynthesis. For the vegetable crops the photosynthesis spectra are very similar to the generalised photosynthesis spectrum. Red light is most efficient for leaf photosynthesis. Light from red (ca. 645nm) LED's was maximally 13% more efficient than High Pressure Sodium light. For reddish leaves of the rose cultivar Prestige, red LED light was up to 35% more efficient. These figures apply to the momentary efficiency of leaf photosynthesis at 100 {mu}mol.m{sup -2}.s{sup -1} (PAR) and suggest that use of red light can lead to higher photosynthesis, especially for certain rose cultivars [Dutch] LED verlichting heeft zijn intrede gedaan in de Nederlandse glastuinbouw. De LED ontwikkeling laat zien dat in de nabije toekomst LED's efficiënter zijn dan SON-T verlichting. Lichtonderschepping en fotosynthese efficiëntie zijn afhankelijk van de kleur van het licht. Voor optimale fotosynthese, groei en ontwikkeling zouden de beste LED kleuren uitgezocht moeten worden. Wageningen UR heeft lichtonderschepping en fotosynthese bij verschillende lichtkleuren onderzocht bij tomaat, komkommer en roos. Protocollen en apparatuur werden ontwikkeld voor meting van bladfotosynthese en lichtonderschepping in het laboratorium en in de kas. Met een gewassimulatiemodel werd de

  4. Rapid detection of Puccinia triticina causing leaf rust of wheat by PCR and loop mediated isothermal amplification.

    Science.gov (United States)

    Manjunatha, C; Sharma, Sapna; Kulshreshtha, Deepika; Gupta, Sangeeta; Singh, Kartar; Bhardwaj, Subhash C; Aggarwal, Rashmi

    2018-01-01

    Leaf rust of wheat caused by Puccinia triticina has significant impact on wheat production worldwide. Effective and quick detection methodologies are required to mitigate yield loss and time constraints associated with monitoring and management of leaf rust of wheat. In the present study, detection of P. triticina has been simplified by developing a rapid, reliable, efficient and visual colorimetric method i.e., loop mediated isothermal amplification of DNA (LAMP). Based on in silico analysis of P. triticina genome, PTS68, a simple sequence repeat was found highly specific to leaf rust fungus. A marker (PtRA68) was developed and its specificity was validated through PCR technique which gave a unique and sharp band of 919 bp in P. triticina pathotypes only. A novel gene amplification method LAMP which enables visual detection of pathogen by naked eye was developed for leaf rust pathogen. A set of six primers was designed from specific region of P. triticina and conditions were optimised to complete the observation process in 60 minutes at 65o C. The assay developed in the study could detect presence of P. triticina on wheat at 24 hpi (pre-symptomatic stage) which was much earlier than PCR without requiring thermal cycler. Sensitivity of LAMP assay developed in the study was 100 fg which was more sensitive than conventional PCR (50 pg) and equivalent to qPCR (100 fg). The protocol developed in the study was utilized for detection of leaf rust infected samples collected from different wheat fields. LAMP based colorimetric detection assay showed sky blue color in positive reaction and violet color in negative reaction after addition of 120 μM hydroxyl napthol blue (HNB) solution to reaction mixture. Similarly, 0.6 mg Ethidium bromide/ml was added to LAMP products, placed on transilluminator to witness full brightness in positive reaction and no such brightness could be seen in negative reaction mixture. Further, LAMP products spread in a ladder like banding pattern in

  5. Modeling canopy-level productivity: is the "big-leaf" simplification acceptable?

    Science.gov (United States)

    Sprintsin, M.; Chen, J. M.

    2009-05-01

    The "big-leaf" approach to calculating the carbon balance of plant canopies assumes that canopy carbon fluxes have the same relative responses to the environment as any single unshaded leaf in the upper canopy. Widely used light use efficiency models are essentially simplified versions of the big-leaf model. Despite its wide acceptance, subsequent developments in the modeling of leaf photosynthesis and measurements of canopy physiology have brought into question the assumptions behind this approach showing that big leaf approximation is inadequate for simulating canopy photosynthesis because of the additional leaf internal control on carbon assimilation and because of the non-linear response of photosynthesis on leaf nitrogen and absorbed light, and changes in leaf microenvironment with canopy depth. To avoid this problem a sunlit/shaded leaf separation approach, within which the vegetation is treated as two big leaves under different illumination conditions, is gradually replacing the "big-leaf" strategy, for applications at local and regional scales. Such separation is now widely accepted as a more accurate and physiologically based approach for modeling canopy photosynthesis. Here we compare both strategies for Gross Primary Production (GPP) modeling using the Boreal Ecosystem Productivity Simulator (BEPS) at local (tower footprint) scale for different land cover types spread over North America: two broadleaf forests (Harvard, Massachusetts and Missouri Ozark, Missouri); two coniferous forests (Howland, Maine and Old Black Spruce, Saskatchewan); Lost Creek shrubland site (Wisconsin) and Mer Bleue petland (Ontario). BEPS calculates carbon fixation by scaling Farquhar's leaf biochemical model up to canopy level with stomatal conductance estimated by a modified version of the Ball-Woodrow-Berry model. The "big-leaf" approach was parameterized using derived leaf level parameters scaled up to canopy level by means of Leaf Area Index. The influence of sunlit

  6. Assessing the ratio of leaf carbon to nitrogen in winter wheat and spring barley based on hyperspectral data

    Science.gov (United States)

    Xu, Xin-gang; Gu, Xiao-he; Song, Xiao-yu; Xu, Bo; Yu, Hai-yang; Yang, Gui-jun; Feng, Hai-kuan

    2016-10-01

    The metabolic status of carbon (C) and nitrogen (N) as two essential elements of crop plants has significant influence on the ultimate formation of yield and quality in crop production. The ratio of carbon to nitrogen (C/N) from crop leaves, defined as ratio of LCC (leaf carbon concentration) to LNC (leaf nitrogen concentration), is an important index that can be used to diagnose the balance between carbon and nitrogen, nutrient status, growth vigor and disease resistance in crop plants. Thus, it is very significant for effectively evaluating crop growth in field to monitor changes of leaf C/N quickly and accurately. In this study, some typical indices aimed at N estimation and chlorophyll evaluation were tested to assess leaf C/N in winter wheat and spring barley. The multi-temporal hyperspectral measurements from the flag-leaf, anthesis, filling, and milk-ripe stages were used to extract these selected spectral indices to estimate leaf C/N in wheat and barley. The analyses showed that some tested indices such as MTCI, MCARI/OSAVI2, and R-M had the better performance of assessing C/N for both of crops. Besides, a mathematic algorithm, Branch-and-Bound (BB) method was coupled with the spectral indices to assess leaf C/N in wheat and barley, and yielded the R2 values of 0.795 for winter wheat, R2 of 0.727 for spring barley, 0.788 for both crops combined. It demonstrates that using hyperspectral data has a good potential for remote assessment of leaf C/N in crops.

  7. Gas-exchange, water use efficiency and yield responses of elite potato (Solanum tuberosum L.) cultivars to changes in atmospheric carbon dioxide concentration, temperature and relative humidity

    DEFF Research Database (Denmark)

    Kaminski, Kacper Piotr; Sørensen, Kirsten Kørup; Nielsen, Kåre Lehmann

    2014-01-01

    photosynthetic water use efficiency (pWUE) by stimulation in net photosynthesis rate (62% and 43% increase of An) with coincident decline in both stomatal conductance (21% and 43% decrease of gs) and leaf transpiration rate (19% and 40% decrease of E) resulting in pWUE increments of 89% and 147%. Furthermore...

  8. Quantitative trait loci for yield and morphological traits in maize under drought stress

    Directory of Open Access Journals (Sweden)

    Nikolić Ana

    2011-01-01

    Full Text Available Drought is one of the most important factors contributing to crop yield loss. In order to develop maize varieties with drought tolerance, it is necessary to explore the genetic basis. Mapping quantitative trait loci (QTL that control the yield and associate agronomic traits is one way of understanding drought genetics. QTLs associated with grain yield (GY, leaf width (LW3, LW4 plant height (PH, ear height (EH, leaf number (NL, tassel branch number (TBN and tassel length (TL were studied with composite interval mapping. A total of 43 QTLs were detected, distributed on all chromosomes, except chromosome 9. Phenotypic variability determined for the identified QTLs for all the traits was in the range from 20.99 to 87.24%. Mapping analysis identified genomic regions associated with two traits in a manner that was consistent with phenotypic correlation among traits, supporting either pleiotropy or tight linkage among QTLs.

  9. A flavonoid mutant of barley (Hordeum vulgare L.) exhibits increased sensitivity to UV-B radiation in the primary leaf

    International Nuclear Information System (INIS)

    Reuber, S.; Bornman, J.F.; Weissenböck, G.

    1996-01-01

    The aim of the present investigation was to define the role of soluble flavonoids as UV-B protectants in the primary leaf of barley (Hordeum vulgare L.). For this purpose we used a mutant line (Ant 287) from the Carlsberg collection of proanthocyanidin-free barley containing only 7% of total extractable flavonoids in the primary leaf as compared to the mother variety (Hiege 550/75). Seven-day-old leaves from plants grown under high visible light with or without supplementary UV-B radiation were used for the determination of UV-B sensitivity. UV-B-induced changes were assessed from parameters of chlorophyll fluorescence of photosystem II, including initial and maximum fluorescence, apparent quantum yield, and photochemical and non-photochemical quenching. A quartz fibre-optic microprobe was used to evaluate the amount of potentially harmful UV-B (310 nm radiation) penetrating into the leaf as a direct consequence of flavonoid deficiency. Our data indicate an essential role of flavonoids in UV-B protection of barley primary leaves. In leaves of the mutant line grown under supplementary UV-B, an increase in 310nm radiation in the mesophyll and a strong decrease in the quantum yield of photosynthesis were observed as compared to the corresponding mother variety. Primary leaves of liege responded to supplementary UV-B radiation with a 30% increase in the major flavonoid saponarin and a 500% increase in the minor compound lutonarin. This is assumed to be an efficient protective response since no changes in variable chlorophyll fluorescence were apparent. In addition, a further reduction in UV-B penetration into the mesophyll was recorded in these leaves

  10. Measured efficiency of a luminescent solar concentrator PV module called Leaf Roof

    NARCIS (Netherlands)

    Reinders, Angèle H.M.E; Debije, Michael G.; Rosemann, Alexander

    2017-01-01

    A functional prototype of a luminescent solar concentrator photovoltaic (LSC PV) module, called Leaf Roof, aims at demonstrating the design features of LSC PV technologies such as coloring, transparency, and flexibility in physical shape. In this paper, the prototype is presented and the first

  11. A leaf-inspired luminescent solar concentrator for energy-efficient continuous-flow photochemistry

    NARCIS (Netherlands)

    Cambié, D.; Zhao, F.; Hessel, V.; Debije, M.G.; Noël, T.

    2017-01-01

    The use of solar light to promote chemical reactions holds significant potential with regard to sustainable energy solutions. While the number of visible light-induced transformations has increased significantly, the use of abundant solar light has been extremely limited. We report a leaf-inspired

  12. Yield and resource use efficiency of Plukenetia volubilis plants at two distinct growth stages as affected by irrigation and fertilization.

    Science.gov (United States)

    Gong, He-De; Geng, Yan-Jing; Yang, Chun; Jiao, Dong-Ying; Chen, Liang; Cai, Zhi-Quan

    2018-01-08

    This study is to test how seedlings (vegetative) and large plants (reproductive) of an oilseed crop (Plukenetia volubilis) responded to regulated deficit irrigation techniques (conventional deficit irrigation, DI; alternative partial root-zone irrigation, APRI) in a tropical humid monsoon area. Seedlings were more sensitive to water deficit than large plants. Although APRI did better than DI in saving water for both seedlings and large plants at the same amount of irrigation, full irrigation (FI) is optimal for faster seedling growth at the expense of water-use efficiency (WUE). The seed number per unit area was responsible for the total seed oil yield, largely depending on the active process of carbon and nitrogen storages at the whole-plant level. The magnitude of the increase in total seed and seed oil yield by fertilization was similar under different irrigation regimes. Compared with FI, DI can save water, but reduced the total seed yield and had lower agronomic nutrient-use efficiency (NUE agr ); whereas APRI had similar total seed yield and NUE agr , but reduced water use greatly. Although the dual goal of increasing the yield and saving water was not compatible, maintaining a high yield and NUEagr at the cost of WUE is recommended for P. volubilis plantation in t he water-rich areas.

  13. Effect of different phosphorus fertilizer rates on N-uptake, N-efficiency and zea maize yield in irrigated soils

    International Nuclear Information System (INIS)

    Khalifa, Kh.

    1993-01-01

    Effect of different rates of P fertilizer on N-uptake, N-efficiency and zea mays (C.V.Lg 11) were studied by use of 15 N technique. The main objectives of this study were to study effect of different level of P on N-utilization and determine the interaction between P and N on zea mays yield, and the efficiency of N-fertilizer during different stages of plant growth. The field experiment was conducted for two years 1985 and 1986. The treatments were 0, 80, 160 Kg N, as urea Co( 15 NH 2 ) 2 and 0, 40, 80, 160 Kg P 2 O 5 as triplsuperphophate. The experiment design was randomized block of four replicates for each treatment. Yield (grain and dry matter), utilization of urea, N-uptake, total N, N-yield, Ndff%, NDF% and A-values were determined. All results indicate that zea mays responds to the addition of nitrogen and the yield increases with the increase of added nitrogen. The highest yield was for N 2 (160 Kg) level during two seasons. Also zea mays responds clearly to phosphorus especially at stages 1 and 2, where dry matter yield increases with the increase of phosphorus rate. The highest yield was for P 3 (160 Kg) rate. While in grain stage the response was for rate P 1 (40 Kg) and P 2 (80 Kg) in comparison with control. However P 1 , rate was dominant over P 2 and P 3 . The effect of P 2 rate on grain yield was very little in comparison with P 1 , while P 3 decreases the grain yield during two seasons in comparison with control. There is an effect of N and P when added both or separately. There is also effect for interaction between them on the yield (grain and dry matter). Generally, from the previous data we can conclude that the rate 160 Kg N/ha and 40 Kg P 2 O 5 /ha were optimum rate for zea mays fertilization in Deir-Ezzor (Syria) and similar areas for grain yield. (author). 17 refs., 6 tabs

  14. Simultaneous minimizing monitor units and number of segments without leaf end abutment for segmental intensity modulated radiation therapy delivery

    International Nuclear Information System (INIS)

    Li Kaile; Dai Jianrong; Ma Lijun

    2004-01-01

    Leaf end abutment is seldom studied when delivering segmental intensity modulated radiation therapy (IMRT) fields. We developed an efficient leaf sequencing method to eliminate leaf end abutment for segmental IMRT delivery. Our method uses simple matrix and sorting operations to obtain a solution that simultaneously minimizes total monitor units and number of segments without leaf end abutment between segments. We implemented and demonstrated our method for multiple clinical cases. We compared the results of our method with the results from exhaustive search method. We found that our solution without leaf end abutment produced equivalent results to the unconstrained solutions in terms of minimum total monitor units and minimum number of leaf segments. We conclude that the leaf end abutment fields can be avoided without affecting the efficiency of segmental IMRT delivery. The major strength of our method is its simplicity and high computing speed. This potentially provides a useful means for generating segmental IMRT fields that require high spatial resolution or complex intensity distributions

  15. Short-term responses of leaf growth rate to water deficit scale up to whole-plant and crop levels: an integrated modelling approach in maize.

    Science.gov (United States)

    Chenu, Karine; Chapman, Scott C; Hammer, Graeme L; McLean, Greg; Salah, Halim Ben Haj; Tardieu, François

    2008-03-01

    Physiological and genetic studies of leaf growth often focus on short-term responses, leaving a gap to whole-plant models that predict biomass accumulation, transpiration and yield at crop scale. To bridge this gap, we developed a model that combines an existing model of leaf 6 expansion in response to short-term environmental variations with a model coordinating the development of all leaves of a plant. The latter was based on: (1) rates of leaf initiation, appearance and end of elongation measured in field experiments; and (2) the hypothesis of an independence of the growth between leaves. The resulting whole-plant leaf model was integrated into the generic crop model APSIM which provided dynamic feedback of environmental conditions to the leaf model and allowed simulation of crop growth at canopy level. The model was tested in 12 field situations with contrasting temperature, evaporative demand and soil water status. In observed and simulated data, high evaporative demand reduced leaf area at the whole-plant level, and short water deficits affected only leaves developing during the stress, either visible or still hidden in the whorl. The model adequately simulated whole-plant profiles of leaf area with a single set of parameters that applied to the same hybrid in all experiments. It was also suitable to predict biomass accumulation and yield of a similar hybrid grown in different conditions. This model extends to field conditions existing knowledge of the environmental controls of leaf elongation, and can be used to simulate how their genetic controls flow through to yield.

  16. The effects of maxicrop leaf fertilizer on the yield and quality of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-17

    Jun 17, 2008 ... doses lead to an increase in seed yield. The highest seed yield ... or small amount of vegetable oil deficit occurs in Turkey. (Arslan et al., 1993). .... Akçin et al. reported that the plant hormone Alar 85, which they applied on four ...

  17. AKTIVITAS ANTIBAKTERI EKSTRAK DAUN SALAM (Syzgium Polyanta DAN DAUN PANDAN (Pandanus Amaryllifolius [Antibacterial Activity Of (Syzygium Polyanta And Amaryllifolius Leaf Extracts

    Directory of Open Access Journals (Sweden)

    Murhadi

    2007-06-01

    Full Text Available The objectives of this research were to study antibacterial activities of syzgium polyanta (“Salam” and Pandanus amaryllifolius (“Pandan” leaf extracts and the effect of wet heating (1000, up to 60 min on their antibacterial activities against staphylococcus aureus, bacillus subtillis, pseudomonas aeruginosa and Escherichia coli. Salam and pandan leaves powder was extracted using hot water (700C, 2 h, ethanol, ethanol/ethylacetate (1:1, v/v, and ethlacetate bt soxhlet (3x8 h separately. Each residue was further extracted using the same solvent by shaker (250 rpm, 24 h. finally filtrates were mixed and evaporated to produce the extract. Salam leaf ethanol extract (yield 11.50% showed highest antibacterial activity especially towards P. aeruginosa (diameter of inhibitor 6.5 mm/mg and B. subtilis (6.3 mm/mg. Pandan leaf erhanol/ethylacetate extract (yield 15.61 % also showed antibacterial activity towards P. aeruginosa (4.25 mm/mg and B. subtilis (3.2 mm/mg. In general, salam leaf extracts showed higher antibacterial activity than pandan leaf extracts. Pandan and salam leaf water extracts had no antibacterial activity. Escerichia coli was more resistant to the extracts compared Staphylococcus aureus, bacillus subtilis, and pseudomonas aeruginosa. Antibacterial activity of salam leaf ethylacetate extract decreased 6.55%, lower than that of pandan leaf ethylacetate extract (18.48% after heating 1000C for 10up to 60 min.

  18. Evaluation of sources of organic manure on the growth and yield of ...

    African Journals Online (AJOL)

    Moringa 20 t ha1 produce the highest dry matter of the plants. The least fruit number of fruits per plant than Kumba and fruit yield in t ha-1 was higher in Gilo. There was no significant interaction between varieties and manure. Yield of both varieties was higher in Makurdi than Obubra Moringa Oleifera leaf biomas and poultry ...

  19. Effect of Water Quality and Drip Irrigation Management on Yield and Water Use Efficiency in Late Summer Melon

    Directory of Open Access Journals (Sweden)

    javad baghani

    2016-02-01

    germinations in the fresh water treatments. However, with increased water salinity, the time of seed germination reduced. The maximum delay in germination of seeds was in the treatment that was irrigated with fresh water from the beginning of cultivation. Number of flowers: First, the male flowers appeared and after 5 to 7 days, the appearance of female flowers began. The effect of irrigation treatments on female flower appearance was significant. With increased water salinity, the number of male flowers decreased. There was the lowest male flower in the treatment that was irrigated with saline water from the beginning, but there was no significant difference among the other treatments. Root, steam and leaves: The effect of saline irrigation water on dried leaves’ weight and dry root weight was significant at 1% and 5% levels, respectively. Fresh treatment and salinity treatment have the least and the most root dries weight, respectively (irrigated from the beginning with fresh or saline water. Two treatments that were irrigated with fresh and brackish water from thebeginning of cultivation have the highest leaf growth. The same trend was true for steams. In general, in all treatments, after applying different quality water to the end of the growing season, the trend of plant growth was similar to the others. Chlorophyll: One of the most common measurements made by plant scientists is the determination of Chlorophyll concentration. The SPAD index was used for comparison of chlorophylls. With an increase of the salt in irrigation water, the SPAD index was also increased. The maximum and minimum SPAD was in the treatments that were irrigated with saline water (treatment A and fresh water (treatment C from the beginning of cultivation, respectively. Yield: With increasing the salinity of water, the total yield decreased. Salinity in irrigation water had a significant effect (at the 5% level on total yield. The mean yield of brackish and salinity irrigation water treatments were

  20. Combining field performance with controlled environment plant imaging to identify the genetic control of growth and transpiration underlying yield response to water-deficit stress in wheat.

    Science.gov (United States)

    Parent, Boris; Shahinnia, Fahimeh; Maphosa, Lance; Berger, Bettina; Rabie, Huwaida; Chalmers, Ken; Kovalchuk, Alex; Langridge, Peter; Fleury, Delphine

    2015-09-01

    Crop yield in low-rainfall environments is a complex trait under multigenic control that shows significant genotype×environment (G×E) interaction. One way to understand and track this trait is to link physiological studies to genetics by using imaging platforms to phenotype large segregating populations. A wheat population developed from parental lines contrasting in their mechanisms of yield maintenance under water deficit was studied in both an imaging platform and in the field. We combined phenotyping methods in a common analysis pipeline to estimate biomass and leaf area from images and then inferred growth and relative growth rate, transpiration, and water-use efficiency, and applied these to genetic analysis. From the 20 quantitative trait loci (QTLs) found for several traits in the platform, some showed strong effects, accounting for between 26 and 43% of the variation on chromosomes 1A and 1B, indicating that the G×E interaction could be reduced in a controlled environment and by using dynamic variables. Co-location of QTLs identified in the platform and in the field showed a possible common genetic basis at some loci. Co-located QTLs were found for average growth rate, leaf expansion rate, transpiration rate, and water-use efficiency from the platform with yield, spike number, grain weight, grain number, and harvest index in the field. These results demonstrated that imaging platforms are a suitable alternative to field-based screening and may be used to phenotype recombinant lines for positional cloning. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  1. Correlated evolution of stem and leaf hydraulic traits in Pereskia (Cactaceae).

    Science.gov (United States)

    Edwards, Erika J

    2006-01-01

    Recent studies have demonstrated significant correlations between stem and leaf hydraulic properties when comparing across species within ecological communities. This implies that these traits are co-evolving, but there have been few studies addressing plant water relations within an explicitly evolutionary framework. This study tests for correlated evolution among a suite of plant water-use traits and environmental parameters in seven species of Pereskia (Cactaceae), using phylogenetically independent contrasts. There were significant evolutionary correlations between leaf-specific xylem hydraulic conductivity, Huber Value, leaf stomatal pore index, leaf venation density and leaf size, but none of these traits appeared to be correlated with environmental water availability; only two water relations traits - mid-day leaf water potentials and photosynthetic water use efficiency - correlated with estimates of moisture regime. In Pereskia, it appears that many stem and leaf hydraulic properties thought to be critical to whole-plant water use have not evolved in response to habitat shifts in water availability. This may be because of the extremely conservative stomatal behavior and particular rooting strategy demonstrated by all Pereskia species investigated. These results highlight the need for a lineage-based approach to understand the relative roles of functional traits in ecological adaptation.

  2. Response of biomass and nitrogen yield of white clover to radiation and atmospheric CO2 concentration

    International Nuclear Information System (INIS)

    Manderscheid, R.; Bender, J.; Schenk, U.; Weigel, H.J.

    1997-01-01

    The objectives of the present study were to test (i) whether the effect of season-long CO 2 enrichment on plant dry matter production of white clover (Trifolium repens cv. Karina) depends on the temperature or can solely be explained by changes in radiation use efficiency, and (ii) whether the atmospheric CO 2 concentration affects the relationship between tissue %N and plant biomass. Plants were grown in pots with adequate nutrient and water supply and were exposed to ambient and above ambient CO 2 concentrations (approximately +80 ppm, +160 ppm, +280 ppm) in open-top chambers for two seasons. Nitrogen fertilizer was given only before the experiment started to promote N 2 fixation. Plants were clipped to a height of 5 cm, when the canopy had reached a height of about 20 cm and when the CO 2 effect had not been diminished due to self-shading of the leaves. Photon exposure (400–700 nm) measured above the canopy was linearly related to the above ground biomass, the leaf area index and the nitrogen yield (r 2 > 0.94). The slopes of the curves depended on the CO 2 concentration. Since most of the radiation (>90%) was absorbed by the foliage, the slopes were used to calculate the CO 2 effect on the radiation use efficiency of biomass production, which is shown to increase curvilinearly between 380 and 660 ppm CO 2 from 2.7 g MJ −1 to 3.9 g MJ −1 . CO 2 enrichment increased above ground biomass by increasing the leaf number, the individual leaf weight and the leaf area; specific leaf weight was not affected. The relative CO 2 response varied between harvests; there was a slight but not significant positive relationship with mean daytime temperature. At the beginning of the season, plant nitrogen concentration in the above ground biomass was decreased by CO 2 enrichment. However, at later growth stages, when the plants depended solely on N 2 fixation, nitrogen concentration was found to be increased when the nitrogen concentration value was adjusted for the decrease

  3. Ozone and Botrytis interactions in onion-leaf dieback: open-top chamber studies

    Energy Technology Data Exchange (ETDEWEB)

    Wukasch, R.T.; Hofstra, G.

    1977-09-01

    Paired open-top chambers were used to study interactions between Botrytis spp. and ozone in field-grown onions. Charcoal filters removed 35 to 65% of the ambient ozone, resulting in six-fold reduction of onion leaf dieback and a 28% increase in onion yield compared with unfiltered chambers. Symptoms of leaf injury appeared soon after ozone levels exceeded 294 ..mu..g/m/sup 3/ (0.15 ppm) for 4 hr. Lesions caused by Botrytis were few because no dew formed in the chambers. However, when leaves were wetted with foggers, inoculation with mycelial suspensions of B. sauamosa in late August produced significantly more lesions and leaf dieback in the unfiltered chamber. Botrytis squamosa, B. cinerea, B. allii, and several genera of secondary fungi were isolated from these lesions. Botrytis squamosa was recovered from lesions only, whereas B. cinerea and B. allii were associated more generally with onion leaf tissue regardless of lesions. 25 references, 1 figure, 2 tables.

  4. Efficient sampling to determine distribution of fruit quality and yield in a commercial apple orchard

    DEFF Research Database (Denmark)

    Martinez Vega, Mabel Virginia; Wulfsohn, D.; Zamora, I.

    2012-01-01

    In situ assessment of fruit quality and yield can provide critical data for marketing and for logistical planning of the harvest, as well as for site-specific management. Our objective was to develop and validate efficient field sampling procedures for this purpose. We used the previously reported...... ‘fractionator’ tree sampling procedure and supporting handheld software (Gardi et al., 2007; Wulfsohn et al., 2012) to obtain representative samples of fruit from a 7.6-ha apple orchard (Malus ×domestica ‘Fuji Raku Raku’) in central Chile. The resulting sample consisted of 70 fruit on 56 branch segments...... of yield. Estimated marketable yield was 295.8±50.2 t. Field and packinghouse records indicated that of 348.2 t sent to packing (52.4 t or 15% higher than our estimate), 263.0 t was packed for export (32.8 t less or -12% error compared to our estimate). The estimated distribution of caliber compared very...

  5. Inducing mutations through γ-irradiation in seeds of Mucuna pruriens for developing high L-DOPA-yielding genotypes.

    Science.gov (United States)

    Singh, Susheel Kumar; Yadav, Deepti; Lal, Raj Kishori; Gupta, Madan M; Dhawan, Sunita Singh

    2017-04-01

    To develop elite genotypes in Mucuna pruriens (L.) DC with high L-DOPA (L-3, 4 dihydroxyphenylalanine) yields, with non-itching characteristics and better adaptability by applying γ-irradiation. Molecular and chemical analysis was performed for screening based on specific characteristics desired for developing suitable genotypes. Developed, mutant populations were analyzed for L-DOPA % in seeds through TLC (thin layer chromatography), and the results obtained were validated with the HPLC (High performance liquid chromatography). The DNA (Deoxyribonucleic acid) was isolated from the leaf at the initial stage and used for DNA polymorphism. RNA (Ribonucleic acid) was isolated from the leaf during maturity and used for expression analysis. The selected mutant T-I-7 showed 5.7% L-DOPA content compared to 3.18% of parent CIM-Ajar. The total polymorphism obtained was 57% with the molecular marker analysis. The gene expression analysis showed higher fold change expression of the dopadecarboxylase gene (DDC) in control compared to selected mutants (T-I-7, T-II-23, T-IV-9, T-VI-1). DNA polymorphism was used for the screening of mutants for efficient screening at an early stage. TLC was found suitable for the large-scale comparative chemical analysis of L-DOPA. The expression profile of DDC clearly demonstrated the higher yields of L-DOPA in selected mutants developed by γ-irradiation in the seeds of the control.

  6. A flux-based assessment of the effects of ozone on foliar injury, photosynthesis, and yield of bean (Phaseolus vulgaris L. cv. Borlotto Nano Lingua di Fuoco) in open-top chambers

    International Nuclear Information System (INIS)

    Gerosa, Giacomo; Marzuoli, Riccardo; Rossini, Micol; Panigada, Cinzia; Meroni, Michele; Colombo, Roberto; Faoro, Franco; Iriti, Marcello

    2009-01-01

    Stomatal ozone uptake, determined with the Jarvis' approach, was related to photosynthetic efficiency assessed by chlorophyll fluorescence and reflectance measurements in open-top chamber experiments on Phaseolus vulgaris. The effects of O 3 exposure were also evaluated in terms of visible and microscopical leaf injury and plant productivity. Results showed that microscopical leaf symptoms, assessed as cell death and H 2 O 2 accumulation, preceded by 3-4 days the appearance of visible symptoms. An effective dose of ozone stomatal flux for visible leaf damages was found around 1.33 mmol O 3 m -2 . Significant linear dose-response relationships were obtained between accumulated fluxes and optical indices (PRI, NDI, ΔF/F m ' ). The negative effects on photosynthesis reduced plant productivity, affecting the number of pods and seeds, but not seed weight. These results, besides contributing to the development of a flux-based ozone risk assessment for crops in Europe, highlight the potentiality of reflectance measurements for the early detection of ozone stress. - Ozone stomatal fluxes affect leaf cell viability, photosynthetic performance, optical properties and crop yield of bean.

  7. Effects of Bois noir on carbon assimilation, transpiration, stomatal conductance of leaves and yield of grapevine (Vitis vinifera) cv. Chardonnay.

    Science.gov (United States)

    Endeshaw, Solomon T; Murolo, Sergio; Romanazz, Gianfranco; Neri, Davide

    2012-06-01

    Bois noir (BN) is one of the main phytoplasma diseases of grapevine (Vitis vinifera). It is widespread, and can cause severe losses in European vineyards. The infective agent colonizes phloem elements and induces visible symptoms of leaf yellowing or reddening after a relatively long incubation period. As the most sensitive cultivars to BN, Chardonnay plants were grouped as healthy or symptomatic in spring, based on the records from the previous year. Leaf gas exchange and chlorophyll a fluorescence were measured weekly from July to September in healthy plants, and in symptomatic and asymptomatic leaves from symptomatic plants. The midday relative water content (mRWC) was measured once per month. The detection of phytoplasma DNA by nested-polymerase chain reaction revealed BN infection in symptomatic leaf samples at the end of September. A significant decrease in pigment content and maximum quantum efficiency of photosystem II (Fv/Fm) of these symptomatic leaves was detected from July to September, although in the asymptomatic leaves of the symptomatic plants the net photosynthesis (Pn) decrease was not significant. In the leaves from the healthy plants, Pn and transpiration were relatively stable. Of note, in July, an initially healthy plant showed a strong Pn reduction that was followed by visible leaf yellowing symptoms only in August. The phytoplasma infection also stimulated significant reductions in mRWC of the symptomatic leaves, with a final large decrease in yield.

  8. Stemphylium leaf spot of parsley in California caused by Stemphylium vesicarium

    Science.gov (United States)

    From 2009 through 2011, a previously undescribed disease occurred on commercial parsley in coastal (Ventura County) California. Symptoms of the disease consisted of circular to oval, tan to brown leaf spots and resulted in loss of crop quality and hence reduced yields. A fungus was consistently isol...

  9. Effect of Different Levels of Sulphur Bentonite on Yield and Yield Components of Canola (Brassica napus L.

    Directory of Open Access Journals (Sweden)

    B Rahimi

    2013-04-01

    Full Text Available In order to determine the effect of different levels of sulfur bentonite on yield and yield components of canola a factorial experiment was conducted on the basis of randomized complete block design with three replications in Mashhad in 2009-2010 growing season. Factors included four levels of sulfur bentonite (0, 300, 400 and 500 kg.h-1 and two varieties of canola (Modena and Zarfam. The result showed that the increase in sulfur increased some vegetative traits such as leaf area index and plant height. Using sulfur caused increased pod number, seed weight, in addition of oil and protein content and seed yield. Grain yield increase was due to seed weight and LAI. Two varieties were different to responses the sulfur. While in no sulfur application there was no significant difference in seed yield, in 500 Kg sulfur application yield of Zarfam compared to Modena increased about 29.63. According to the results there are significant differences between cultivars in terms of response to the sulfur fertilizer. Therefore it is necessary to evaluate effect of sulfur application of canola productivity in different climate conditions of Iran.

  10. Species of Cercospora associated with grey leaf spot of maize

    NARCIS (Netherlands)

    Crous, P.W.; Groenewald, J.Z.; Groenewald, M.; Caldwell, P.; Braun, U.; Harrington, T.C.

    2006-01-01

    Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. The causal organism associated with the disease is Cercospora zeae-maydis. Two potential sibling species have been recognized as Groups I and II. The DNA sequences for the

  11. Species of Cercospora associated with grey leaf spot of maize.

    NARCIS (Netherlands)

    Crous, P.W.; Groenewald, J.Z.; Groenewald, M.; Caldwell, P.; Braun, U.; Harrington, T.C.

    2006-01-01

    Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. The causal organism associated with the disease is Cercospora zeae-maydis. Two potential sibling species have been recognized as Groups I and II. The DNA sequences for the

  12. Solar radiation measurements and Leaf Area Index (LAI) from vegetal covers

    International Nuclear Information System (INIS)

    Wandelli, E.V.; Marques Filho, A. de O.

    1999-01-01

    A method by which a physical model of the solar radiation transfer in a vegetal medium is inverted to estimate the leaf area index (LAI) for different types of vegetation is presented here, as an alternative to the destructive experiments, which are a hard task to implement on the vegetation covers. Radiation data were obtained during the dry season — 1996, at the Embrapa Experimental Station, (BR 174 - km 54, 2° 31' S, 60° 01' W), Manaus, Brazil. The method yielded convergent values for the LAI between different adopted radiation classes with more stable estimates at time when there is a predominant diffuse radiation. The application of the inversion algorithm yields the following values for the leaf area index and respective annual foliage increments: 3.5 (0.35 yr. -1 ) for the intact secondary forest; 2.0 (0.5 yr -1 ) for the palm agroforestry system; and 1.6 (0.4 yr -1 ) for the multi-layer ones [pt

  13. Foliar copper uptake by maize plants: effects on growth and yield

    Directory of Open Access Journals (Sweden)

    Rogério Hidalgo Barbosa

    2013-09-01

    Full Text Available A slight increase in the levels of a certain nutrient can cause a significant increase in crop yield or can cause phytotoxicity symptoms. Thus, the aim of this study was to evaluate the effect of foliar application of copper (Cu on the growth and yield of DG-501 maize. The experiment was carried out between December 2009 and April 2010 in conventional tillage. When plants were with six to eight leaves, Cu (0, 100, 200, 300, 400, 500 and 600g ha-1 was applied to the leaves. Treatments were arranged in randomized complete block with five replications. When 50% of the plants were in flowering, it was evaluated the plant height, culm diameter, height of the first ear insertion, leaf area, and chlorophyll content. At harvest, it was evaluated diameter and length of the ear, yield and thousand grain weight. There was a linear reduction in the plant height and in the height of the first ear insertion with increasing Cu doses. On the other hand, chlorophyll content, leaf area, diameter and length of ear, thousand grain weight and yield increased at doses up to 100g ha-1 Cu, however, decreased at higher doses. Therefore, foliar Cu application at doses higher than 100g ha-1 has toxic effect in maize plants with losses in growth and yield.

  14. Coordination of Leaf Photosynthesis, Transpiration, and Structural Traits in Rice and Wild Relatives (Genus Oryza).

    Science.gov (United States)

    Giuliani, Rita; Koteyeva, Nuria; Voznesenskaya, Elena; Evans, Marc A; Cousins, Asaph B; Edwards, Gerald E

    2013-07-01

    The genus Oryza, which includes rice (Oryza sativa and Oryza glaberrima) and wild relatives, is a useful genus to study leaf properties in order to identify structural features that control CO(2) access to chloroplasts, photosynthesis, water use efficiency, and drought tolerance. Traits, 26 structural and 17 functional, associated with photosynthesis and transpiration were quantified on 24 accessions (representatives of 17 species and eight genomes). Hypotheses of associations within, and between, structure, photosynthesis, and transpiration were tested. Two main clusters of positively interrelated leaf traits were identified: in the first cluster were structural features, leaf thickness (Thick(leaf)), mesophyll (M) cell surface area exposed to intercellular air space per unit of leaf surface area (S(mes)), and M cell size; a second group included functional traits, net photosynthetic rate, transpiration rate, M conductance to CO(2) diffusion (g(m)), stomatal conductance to gas diffusion (g(s)), and the g(m)/g(s) ratio.While net photosynthetic rate was positively correlated with gm, neither was significantly linked with any individual structural traits. The results suggest that changes in gm depend on covariations of multiple leaf (S(mes)) and M cell (including cell wall thickness) structural traits. There was an inverse relationship between Thick(leaf) and transpiration rate and a significant positive association between Thick(leaf) and leaf transpiration efficiency. Interestingly, high g(m) together with high g(m)/g(s) and a low S(mes)/g(m) ratio (M resistance to CO(2) diffusion per unit of cell surface area exposed to intercellular air space) appear to be ideal for supporting leaf photosynthesis while preserving water; in addition, thick M cell walls may be beneficial for plant drought tolerance.

  15. Impact of Leaf Removal, Applied Before and After Flowering, on Anthocyanin, Tannin, and Methoxypyrazine Concentrations in 'Merlot' (Vitis vinifera L.) Grapes and Wines.

    Science.gov (United States)

    Sivilotti, Paolo; Herrera, Jose Carlos; Lisjak, Klemen; Baša Česnik, Helena; Sabbatini, Paolo; Peterlunger, Enrico; Castellarin, Simone Diego

    2016-06-08

    The development and accumulation of secondary metabolites in grapes determine wine color, taste, and aroma. This study aimed to investigate the effect of leaf removal before flowering, a practice recently introduced to reduce cluster compactness and Botrytis rot, on anthocyanin, tannin, and methoxypyrazine concentrations in 'Merlot' grapes and wines. Leaf removal before flowering was compared with leaf removal after flowering and an untreated control. No effects on tannin and anthocyanin concentrations in grapes were observed. Both treatments reduced levels of 3-isobutyl-2-methoxypyrazine (IBMP) in the grapes and the derived wines, although the after-flowering treatment did so to a greater degree in the fruit specifically. Leaf removal before flowering can be used to reduce cluster compactness, Botrytis rot, and grape and wine IBMP concentration and to improve wine color intensity but at the expense of cluster weight and vine yield. Leaf removal after flowering accomplishes essentially the same results without loss of yield.

  16. Effect of nitrogen fertilizer application timing on nitrogen use efficiency and grain yield of winter wheat in Ireland

    Directory of Open Access Journals (Sweden)

    Efretuei A.

    2016-06-01

    Full Text Available The objectives of this work were to determine the effects of initiating application of fertilizer nitrogen (N to winter wheat at different growth stages (GSs on grain yield and N use efficiency (NUE. A factorial experiment was carried out in two growing seasons (2011 and 2012 with five timings of first N application (GS 24/26 [tillering], GS 30, GS 31, GS 32 or GS 37 and an unfertilized control, two sowing densities (100 and 400 seeds/m2 and a cattle slurry treatment (with or without slurry. The latter was included to simulate variation in soil N supply (SNS. Delaying the first application of N from the tillering stage until GS 30 had no significant effect on grain yield in either year. Further delaying the initial N application until GS 31 caused a significant yield reduction in 2011, in comparison to GS 30 application, but not in 2012. Differences in efficiency of recovery and use of fertilizer N by the crop among the first three application timings were small. There was no evidence to support alteration in the timing of the first application of N in response to low plant density. Slurry application did not influence SNS, so the interaction between SNS and fertilizer N application timing could not be determined. It is concluded that in order to maximise yield and NUE, the first N application should be applied to winter wheat between late tillering and GS 30 and that delaying the first N until GS 31 can lead to yield reductions compared to the yield obtained with earlier application.

  17. Effect of Different Nitrogen Levels on Phenology, Growth Indices and Yield of two Lentil Cultivars under Rainfed Conditions in Mashhad

    Directory of Open Access Journals (Sweden)

    M Bannayan Aval

    2018-02-01

    Full Text Available Introduction Lentil (Lens Culinarris Medik. is an important pulse crop in Iran and is usually grown in rainfed areas. The average lentil yield in Iran is 1195 and 476 Kg.ha-1 in irrigated and rainfed farms, respectively. Low productivity occurs due to different factors. One of these factors is poor agronomic management practices that applied by the farmers, e.g. Limitation or inappropriate fertilizer distribution. Plant development occurs in a number of consecutive phases. These phases can be affected by temperature, moisture, photoperiod, cultivar and other factors. The amount of available nitrogen affects the distribution of assimilates between vegetative and reproductive organs and phenological stages of growth. Therefore, analysis of growth indices and its effective factors can be used as a suitable tool in evaluating the yield. The aim of this study was to evaluate the effect of different nitrogen levels on phenology and growth indices of two lentil cultivars in rainfed conditions of Mashhad. Materials and Methods The experiment was conducted as split plot layout based on randomized complete blocks design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad, during growth season 2016. Nitrogen fertilizer as urea (in three levels i.e. 0, 40 and 80 kg.ha-1 and cultivar (in two levels i.e. Birjand and Robat were in main plots and sub plots, respectively. To determine the leaf area and dry matter, sampling was done every two weeks during the growing season. Phenological stages timing for each plot were determined based on 50% of emergence, 50% of flowering, 50% of maturity. Final yield was estimated from three square meter from each plot. Data were analyzed with the SAS software; the means were compared with Duncan's multiple range tests at the 5% level of probability. The graphs were prepared by SigmaPlot software. Results and Discussion The results showed that the effect of urea fertilizer was

  18. Crop growth in early spring and radiation use efficiency in alfalfa

    International Nuclear Information System (INIS)

    Akmal, M.; Farid, U.; Asim, M.; Farhatullah, A.; Raziuddin, A.

    2011-01-01

    The study was conducted at Agronomy Research Farm, KP Agricultural University Peshawar. Fifteen alfalfa lines (M. sativa L.) were compared for crop growth rate (CGR), biomass yield and radiation use efficiency (RUE). The previous year experiment was defoliated on March, 13 2006 at ground levels about 5 cm height. Fertilizer to the crop was applied every year in first week of March to yield 30, 60, and 30 kg ha/sup -1/ N, P, and K, respectively after defoliation. Periodic samples were harvested from one meter row length at two locations and oven dried at 70 degree C for about 36 h. Before samples, periodic leaf area index (LAI) was recorded with LI-2000 (LI-COR, USA) and subsequently light measurements were made using data logger (LI-1400, LI-COR, USA) and light sensors LI-190 and LI-191 (LI-COR, USA). The CGR showed variation in shapes and asymptotes for the different alfalfa lines which resulted differences in both fresh and dry matters yield at final sampling harvest. Alfalfa line Gramma-2 was the highest in dry matter yield (110 g m-2) followed by Flewish-pop (107 g m-2). Alfalfa line Pumha with 74 g m-2 was the lowest in dry matter yield. Differences were observed in LAI (p<0.05). High dry matter yield of alfalfa line Gramma-2 was due to higher LAI which was associated to highest leaf fraction (38%). Differences in RUE were also observed among the lines. Flewish-pop was the highest in RUE (0.20 g DM MJ-2 PAR absorbed), followed by Gramma-2 (0.18 g DM MJ-2 PAR absorbed). Mean CGR and RUE of the different lines showed association with dry matter yield of which the lateral one showed a strong association compared with the earlier one. We conclude that higher RUE than CGR is important for the line/variety to get quality fodder production. (author)

  19. Sugarbeet leaf spot disease (Cercospora beticola Sacc.)dagger.

    Science.gov (United States)

    Weiland, John; Koch, Georg

    2004-05-01

    SUMMARY Leaf spot disease caused by Cercospora beticola Sacc. is the most destructive foliar pathogen of sugarbeet worldwide. In addition to reducing yield and quality of sugarbeet, the control of leaf spot disease by extensive fungicide application incurs added costs to producers and repeatedly has selected for fungicide-tolerant C. beticola strains. The genetics and biochemistry of virulence have been examined less for C. beticola as compared with the related fungi C. nicotianae, C. kikuchii and C. zeae-maydis, fungi to which the physiology of C. beticola is often compared. C. beticola populations generally are not characterized as having race structure, although a case of race-specific resistance in sugarbeet to C. beticola has been reported. Resistance currently implemented in the field is quantitatively inherited and exhibits low to medium heritability. Cercospora beticola Sacc.; Kingdom Fungi, Subdivision Deuteromycetes, Class Hyphomycetes, Order Hyphales, Genus Cercospora. Circular, brown to red delimited spots with ashen-grey centre, 0.5-6 mm diameter; dark brown to black stromata against grey background; pale brown unbranched sparingly septate conidiophores, hyaline acicular conidia, multiseptate, from 2.5 to 4 microm wide and 50-200 microm long. Propagative on Beta vulgaris and most species of Beta. Reported on members of the Chenopodiaceae and on Amaranthus. Disease symptoms: Infected leaves and petioles of B. vulgaris exhibit numerous circular leaf spots that coalesce in severe cases causing complete leaf collapse. Dark specks within a grey spot centre are characteristic for the disease. Older leaves exhibit a greater number of lesions with larger spot diameter. During the latter stage of severe epiphytotics, new leaf growth can be seen emerging from the plant surrounded by prostrate, collapsed leaves. Fungicides in the benzimidazole and triazole class as well as organotin derivatives and strobilurins have successfully been used to control Cercospora

  20. "Breath figures" on leaf surfaces-formation and effects of microscopic leaf wetness.

    Science.gov (United States)

    Burkhardt, Juergen; Hunsche, Mauricio

    2013-01-01

    "Microscopic leaf wetness" means minute amounts of persistent liquid water on leaf surfaces which are invisible to the naked eye. The water is mainly maintained by transpired water vapor condensing onto the leaf surface and to attached leaf surface particles. With an estimated average thickness of less than 1 μm, microscopic leaf wetness is about two orders of magnitude thinner than morning dewfall. The most important physical processes which reduce the saturation vapor pressure and promote condensation are cuticular absorption and the deliquescence of hygroscopic leaf surface particles. Deliquescent salts form highly concentrated solutions. Depending on the type and concentration of the dissolved ions, the physicochemical properties of microscopic leaf wetness can be considerably different from those of pure water. Microscopic leaf wetness can form continuous thin layers on hydrophobic leaf surfaces and in specific cases can act similar to surfactants, enabling a strong potential influence on the foliar exchange of ions. Microscopic leaf wetness can also enhance the dissolution, the emission, and the reaction of specific atmospheric trace gases e.g., ammonia, SO2, or ozone, leading to a strong potential role for microscopic leaf wetness in plant/atmosphere interaction. Due to its difficult detection, there is little knowledge about the occurrence and the properties of microscopic leaf wetness. However, based on the existing evidence and on physicochemical reasoning it can be hypothesized that microscopic leaf wetness occurs on almost any plant worldwide and often permanently, and that it significantly influences the exchange processes of the leaf surface with its neighboring compartments, i.e., the plant interior and the atmosphere. The omission of microscopic water in general leaf wetness concepts has caused far-reaching, misleading conclusions in the past.

  1. Soil phosphorus dynamics and availability and irrigated coffee yield

    Directory of Open Access Journals (Sweden)

    Thiago Henrique Pereira Reis

    2011-04-01

    Full Text Available Research data have demonstrated that the P demand of coffee (Coffea arabica L. is similar to that of short-cycle crops. In this context, the objective of this study was to evaluate the influence of annual P fertilization on the soil P status by the quantification of labile, moderately labile, low-labile, and total P fractions, associating them to coffee yield. The experiment was installed in a typical dystrophic Red Latosol (Oxisol cultivated with irrigated coffee annually fertilized with triple superphosphate at rates of 0, 50, 100, 200, and 400 kg ha-1 P2O5. Phosphorus fractions were determined in two soil layers: 0-10 and 10-20 cm. The P leaf contents and coffee yield in 2008 were also evaluated. The irrigated coffee responded to phosphate fertilization in the production phase with gains of up to 138 % in coffee yield by the application of 400 kg ha-1 P2O5. Coffee leaf P contents increased with P applications and stabilized around 1.98 g kg-1, at rates of 270 kg ha-1 P2O5 and higher. Soil P application caused, in general, an increase in bioavailable P fractions, which constitute the main soil P reservoir.

  2. Homologous leaf mutations induced in small- and large seeded lentils and their effect on some economic characters

    International Nuclear Information System (INIS)

    Sharma, S.K.; Sharma, B.

    1978-01-01

    Large-seeded 'L 1492' and small-seeded 'L 235' varieties of lentil (Lens culinaris Medic.) were treated with gamma-rays and NMU (N-nitroso-N-methyl urea.). The leaves of the 2 groups are also usually large and small respectively. Some homologous leaf mutations were isolated in both the varieties. In the small-seeded variety, leaf mutations similar to the large-seeded variety were induced and vice versa. The leaf mutations in the 2 groups did not show any change in pod or seed size. Thus the genes responsible for taxonomic differentiation of the small and large-seeded types seem to be different from those reported here, which simply modify the leaf morphology. The seed yield of all the leaf mutants was less than that of the parent varieties. (author)

  3. Milk yield, feed efficiency and metabolic profiles in Jersey and Holstein cows assigned to different fat supplementation strategies

    DEFF Research Database (Denmark)

    Alstrup, Lene; Nielsen, M.O.; Lund, Peter

    2015-01-01

    , compared to their lowest recorded weight after calving. Subsequently, the cows were randomly assigned to one of the four treatments until the end of lactation. There was no effect of feeding strategy on DM intake during week 9–40 of lactation. Fat supplemented rations (WCR; RPF) increased yield of milk...... energy efficiency in Jersey cows but increased energy efficiency in Holstein cows. Because fat supplementation reduced dietary protein concentration and increased milk production, protein intake was lower and N efficiency was higher on WCR and RPF than on CON. Metabolite concentrations in jugular vein...

  4. Carbon isotope discrimination as a selection tool for high water use efficiency and high crop yields

    Energy Technology Data Exchange (ETDEWEB)

    Kumarasinghe, K S; Kirda, C; Bowen, G D [Joint FAO/IAEA Div. of Nuclear Techniques in Food and Agriculture, Vienna (Austria). Soil Fertility, Irrigation and Crop Production Section; Zapata, F; Awonaike, K O; Holmgren, E; Arslan, A; De Bisbal, E C; Mohamed, A R.A.G.; Montenegro, A [FAO/IAEA Agriculture and Biotechnology Lab., Seibersdorf (Austria). Soils Science Unit

    1996-07-01

    Results of back-up research conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in support of the FAO/IAEA Co-ordinated Research Programme on the Use of Isotope Studies on Increasing and Stabilizing Plant Productivity in Low Phosphate and Semi-arid and Sub-humid Soils of the Tropics and Sub-tropics, are presented here. Neutron probe measurements confirmed the earlier reports of a strong correlation of {Delta} with grain yield and water use efficiency of wheat. High soil gypsum content and soil salinity, a wide spread problem in soils of arid and semi-arid climatic zones, do not interfere with the association of {Delta} with crop yields, provided plants are grown in similar soil water status and soil fertility level. Results of a glasshouse experiment using selected cowpea genotypes showed that {Delta} values measured at flowering stage positively correlated with total dry matter production and percent N{sub 2} derived from atmosphere (%Ndfa), contributing to an earlier report from the laboratory that it may be possible to use {Delta} values for screening of leguminous crops for high N{sub 2} fixation potential. {sup 13}C isotope discrimination in the leaves of Gliricidia sepium was measured to examine if the technique could be extended to studies with trees. Results of a glasshouse experiment with 18 provenances of Gliricidia sepium showed highly significant correlations of {Delta} with total dry matter production, water use efficiency and total N accumulated through biological nitrogen fixation. Although the correlation of {Delta} with water use efficiency and dry matter yield are relatively clear and better understood, the correlation with nitrogen fixation still needs a closer examination under different environmental conditions and with different species. (Abstract Truncated)

  5. Impacts of multiple global environmental changes on African crop yield and water use efficiency: Implications to food and water security

    Science.gov (United States)

    Pan, S.; Yang, J.; Zhang, J.; Xu, R.; Dangal, S. R. S.; Zhang, B.; Tian, H.

    2016-12-01

    Africa is one of the most vulnerable regions in the world to climate change and climate variability. Much concern has been raised about the impacts of climate and other environmental factors on water resource and food security through the climate-water-food nexus. Understanding the responses of crop yield and water use efficiency to environmental changes is particularly important because Africa is well known for widespread poverty, slow economic growth and agricultural systems particularly sensitive to frequent and persistent droughts. However, the lack of integrated understanding has limited our ability to quantify and predict the potential of Africa's agricultural sustainability and freshwater supply, and to better manage the system for meeting an increasing food demand in a way that is socially and environmentally or ecologically sustainable. By using the Dynamic Land Ecosystem Model (DLEM-AG2) driven by spatially-explicit information on land use, climate and other environmental changes, we have assessed the spatial and temporal patterns of crop yield, evapotranspiration (ET) and water use efficiency across entire Africa in the past 35 years (1980-2015) and the rest of the 21st century (2016-2099). Our preliminary results indicate that African crop yield in the past three decades shows an increasing trend primarily due to cropland expansion (about 50%), elevated atmospheric CO2 concentration, and nitrogen deposition. However, crop yield shows substantially spatial and temporal variation due to inter-annual and inter-decadal climate variability and spatial heterogeneity of environmental drivers. Climate extremes especially droughts and heat wave have largely reduced crop yield in the most vulnerable regions. Our results indicate that N fertilizer could be a major driver to improve food security in Africa. Future climate warming could reduce crop yield and shift cropland distribution. Our study further suggests that improving water use efficiency through land

  6. BREEAM Green Leaf Eco-rating Program

    International Nuclear Information System (INIS)

    2001-01-01

    The environmental performance of buildings is measured for several reasons, the main one being that it can help owners decide where to invest their retrofit dollars to maximize the energy performance of their building and reduce operating costs. The buildings constructed in the 1950s and 1960s in North America are reaching obsolescence and will require major retrofits to improve their energy efficiency, particularly in the area of mechanical equipment. In addition to reducing operating costs, better maintenance and environmental management of buildings can also address issues such as comfort, health, indoor air quality and productivity. In order to accurately measure the environmental performance of a building, it is necessary to develop a comprehensive measuring and benchmarking tool that would allow occupants to compare the buildings' performance with others. In this pilot study, 6 high-rise multi-residential buildings were assessed for environmental performance using the BREEAM Green Leaf assessment method. The methodology originated in Canada and was developed by ECD Energy, Environment Canada and Terra Choice. It combines the BREEAM set of environmental issues with the Green Leaf Eco-Rating technique. The method covers occupant health, energy efficiency, resource efficiency, environmental responsibility and affordability. Operation and management issues are also taken into consideration. The buildings used in this study were located in various locations, ranging from inner city housing to city/suburban areas. 2 tabs., 17 figs

  7. ROOTSTOCK-SCION INTERACTION: 1. EFFECT ON THE YIELD COMPONENTS OF CABERNET SAUVIGNON GRAPEVINE

    Directory of Open Access Journals (Sweden)

    ALBERTO MIELE

    Full Text Available ABSTRACT The interaction between rootstock, scion and environment can induce different responses to the grapevine physiology. Thus, the aim of this study was to determine the rootstock effect on the yield components of Cabernet Sauvignon (CS grapevine grown in the Serra Gaúcha viticultural region. The experimental design was completely randomized blocks, with 15 treatments, three replicates and ten vines per plot. The results show that all variables evaluated were significantly affected by the year and the rootstock. The CS/Solferino was among other combinations influenced by the year and had higher significant yield/ vine. Indeed, it was higher than that CS/Rupestris du Lot, CS/101-14 Mgt., CS/3309 C, CS/5BB K, CS/161- 49 C, CS/1103 P. and CS/Isabel. The number of clusters/bud, per burst bud and per vine and the weight of clusters were affected by the rootstock as well. Pruning weight/vine, yield/pruning weight, leaf area/vine, leaf area index and leaf area/fresh fruit weight are variables related to the physiology of grapevine which were also affected by the rootstock. In general, rootstocks had adapted well to the environment where the experiment was carried out, giving vigor and high yield to Cabernet Sauvignon grapevine, which means that they may be used by grape growers in this region. However, the choice of the right rootstock depends on various aspects, such as those related to the soil characteristics, climate conditions, grape varieties, and even clones, and production purposes.

  8. Leaf and shoot water content and leaf dry matter content of Mediterranean woody species with different post-fire regenerative strategies.

    Science.gov (United States)

    Saura-Mas, S; Lloret, F

    2007-03-01

    Post-fire regeneration is a key process in Mediterranean shrubland dynamics, strongly determining the functional properties of the community. In this study, a test is carried out to determine whether there is co-variation between species regenerative types and functional attributes related to water use. An analysis was made of the seasonal variations in leaf relative water content (RWC), leaf dry matter content (LDMC), leaf moisture (LM) and live fine fuel moisture (LFFM) in 30 woody species of a coastal shrubland, with different post-fire regenerative strategies (seeding, resprouting or both). RWC results suggest that the studied resprouters have more efficient mechanisms to reduce water losses and maintain water supply between seasons. In contrast, seeders are more drought tolerant. LDMC is higher in resprouters over the course of the year, suggesting a more efficient conservation of nutrients. The weight of the phylogenetic constraint to understand differences between regenerative strategies tends to be important for LDMC, while it is not the case for variables such as RWC. Groups of species with different post-fire regenerative strategies (seeders and resprouters) have different functional traits related to water use. In addition to the role of phylogenetical constraints, these differences are also likely to be related to the respective life history characteristics. Therefore, the presence and abundance of species with different post-fire regenerative responses influence the functional properties of the communities.

  9. Changes in Growth and Oil Yield Indices of Rapeseed (Brassica napus L., cv. Hyola 401 in Different Concentrations andTimes of Application of Supplementary Nitrogen Fertilizer

    Directory of Open Access Journals (Sweden)

    P. Tousi Kehal

    2013-03-01

    Full Text Available In order to investigate the effect of concentration and time of supplementary nitrogen fertilizer spray on growth indices of rapeseed (cv. Hyola 401, a field experiment was conducted at Rice Research Institute of Iran as a randomized complete blocks design with 16 treatments and 3 replications in 2008-2009. The treatments included concentration of nitrogen fertilizer (urea at two levels (5 and 10 ppm in seven levels of application time:1 spraying at 6-8- leaf stage, 2 beginning of stem elongation, 3 prior to flowering, 4 at 6-8- leaf stage + beginning of stem elongation, 5 at 6-8- leaf + prior to flowering, 6 beginning of stem elongation+ prior to flowering, and 7 at 6-8- leaf + beginning of stem elongation+ prior to flowering, which were compared with two control treatments (no fertilizer nitrogen and conventional soil fertilization. Results showed that significant difference was observed between spray treatments including concentration and times of nitrogen application, between controls and between controls with spray treatments, of grain and oil yield, crop growth rate (CGR, leaf area index (LAI and leaf area duration (LAD. Application of nitrogen (10 ppm at the beginning of stem elongation+ prior to flowering stages produced maximum grain yield (4221.7 kg/ha and oil yield (1771.1 kg/ha. Spray treatments produced maximum oil yield index (15.3% compared to controls. Maximum LAI (6.9 and 5.6 respectively, CGR (15.2 and 14.3 g/m2.10 GDD, respectively and LAD (1204 and 1029 cm2/10 GDD, respectively were also obtained from spray application of nitrogen (10 ppm at the beginning of stem elongation+ prior to flowering stages and at 6-8-leaf stage + beginning of stem elongation + prior to flowering. According to the results of the present investigation, it seems that foliar application of supplementary nitrogen fertilizer at the end growth stages (beginning of stem elongation and prior to flowering of rapeseed plants may help to enhance growth indices

  10. Forage yield and nutritive value of Panicum maximum genotypes in the Brazilian savannah

    Directory of Open Access Journals (Sweden)

    Francisco Duarte Fernandes

    2014-02-01

    Full Text Available The narrow genetic variability of grasslands and the incidence of new biotic and abiotic stresses have motivated the selection of new Panicum maximum genotypes for use as forage for beef cattle in the Brazilian savannah. This study aimed to evaluate forage yield and nutritive value of P. maximum genotypes including 14 accessions (PM30 to PM43, four intraspecific hybrids (PM44 to PM47 and six cultivars (Aruana, Massai, Milênio, Mombaça, Tanzania and Vencedor, examining 24 genotypes over two years (2003 and 2004. Milênio cultivar was the genotype with the highest dry matter yield (DMY in both years (18.4 t ha-1 and 20.9 t ha-1, respectively although it presented a high proportion of stems (~ 30%. Genotypes that showed higher Leaf DMY in both years were the accession PM34 (14.7 t ha-1 and the hybrid PM46 (14.0 t ha-1, while Mombaça and Tanzania yielded 12.5 and 11.0 t ha-1, respectively. Leaf organic matter digestibility and leaf DMY for PM40 and PM46 genotypes exceeded the mean (> 656 g kg-1 and > 11.7 t ha-1, respectively. For this reason, PM40 and PM46 can be considered promising P. maximum genotypes for use as forage for grazing systems in the Brazilian savannah.

  11. [Impacts of drought stress on the growth and development and grain yield of spring maize in Northeast China].

    Science.gov (United States)

    Ji, Rui-Peng; Che, Yu-Sheng; Zhu, Yong-Ning; Liang, Tao; Feng, Rui; Yu, Wen-Ying; Zhang, Yu-Shu

    2012-11-01

    Taking spring maize variety Danyu-39 as test object, an experiment was conducted in a large-scale agricultural water controlling experimental field to study the impacts of drought stress at three key growth stages, i. e. , 3-leaf-jointing, jointing-silking, and silking-milk ripe, on the growth and development and grain yield of spring maize in Northeast China. Two treatments were installed, including moderate drought stress (MS) and re-watering to suitable water (CK). Compared with CK, the MS at 3-leaf-jointing stage postponed the whole growth period of Danyu-39 by 13 d, and the plant height and leaf area at jointing stage were decreased by 29.8% and 41.2%, respectively. After re-watering, the plant height and grain yield recovered obviously, and the differences in ear characteristics and final yield were insignificant. The MS at jointing-silking stage shortened the whole growth period by 7 d, the plant height and leaf area at silking stage were decreased by 18.6% and 14.1%, respectively, the ear length, grain number per ear, ear dry mass, and grain mass per ear decreased by 6.9%, 19.1%, 28.1%, and 29.4%, respectively, and the blank stem rate increased by 13.3%. When the maize suffered from moderate drought stress at silking-milk ripe stage, the whole growth period was shortened by 15 d, the plant height and leaf area at milk ripe stage were decreased by 2.3% and 37.3%, respectively, the ear length, grain number per ear, ear dry mass, and grain mass per ear decreased by 9.2%, 24.1%, 30.8%, and 27.9%, respectively, and the blank stem rate increased by 24.5%. After re-watering at the latter two stages, the recovery of plant height was little, and the grain yield decreased significantly.

  12. Response of Cotton to Irrigation Methods and Nitrogen Fertilization: Yield Components, Water-Use Efficiency, Nitrogen Uptake, and Recovery

    International Nuclear Information System (INIS)

    Janat, M.

    2009-01-01

    Efficient crop use of nitrogen (N) fertilizer is critical from economic and environmental viewpoints, especially under irrigated conditions. Cotton yield parameters, fiber quality, water- and N-use efficiency responses to N, and irrigation methods in northern Syria were evaluated. Field trials were conducted for two growing seasons on a Chromoxerertic Rhodoxeralf soil. Treatments consisted of drip fertigation, furrow irrigation, and five different rates of N fertilizer (50, 100, 150, 200, and 250 kg N /ha). Cotton was irrigated when soil moisture in the specified active root depth was 80% of the field capacity as indicated by the neutron probe. Seed cotton yield was higher than the national average (3,928 kg/ha) by at least 12% as compared to all treatments. Lint properties were not negatively affected by the irrigation method or N rates. Water savings under drip fertigation ranged between 25 and 50% of irrigation water relative to furrow irrigation. Crop water-use efficiencies of the drip-fertigated treatments were in most cases 100% higher than those of the corresponding furrow-irrigated treatments. The highest water demand was during the fruit-setting growth stage. It was also concluded that under drip fertigation, 100 -150 N kg/ha was adequate and comparable with the highest N rates tested under furrow irrigation regarding lint yield, N uptake, and recovery. Based on cotton seed yield and weight of stems, the overall amount of N removed from the field for the drip-fertigated treatments ranged between 101-118 kg and 116-188 N/ha for 2001 and 2002, respectively. The N removal ranged between 94-113 and 111-144 kg N/ha for the furrow-irrigated treatments for 2001 and 2002, respectively. (author)

  13. Upland cotton growth and yield response to timing the initial postplant irrigation

    International Nuclear Information System (INIS)

    Steger, A.J.; Silvertooth, J.C.; Brown, P.W.

    1998-01-01

    Cotton (Gossypium spp.) production in arid and semiarid regions depends on well-managed irrigation systems for optimum yield and production efficiency. Water deficit stress early in the growing season can affect the subsequent growth and development of short-season cotton. A 2-yr field study was conducted in southern Arizona to determine the optimum timing of the initial postplant irrigation for a short-season upland cotton variety based on midday leaf water potential (LWP) measurements, and to evaluate the season-long effects of delayed irrigation on subsequent plant growth patterns. In both years, the short-season upland variety, DPL 20, was planted into a Pima clay loam soil [fine-silty, mixed (calcareous), thermic Typic Torrifluvent] that had received a preplant irrigation of 152 (1993) or 254 mm (1994) approximately 3 wk prior to planting. Treatments, designated T1, T2, and T3, received the initial postplant irrigation when the average midday LWP of the uppermost, fully expanded leaf measured −1.5, −1.9, and −2.3 MPa, respectively. Daily midday LWP measurements were taken using the pressure chamber technique. Soil water was measured at 25-cm depth increments using neutron attenuation. Plant height, number of mainstem nodes, nodes above white flower (NAWF), and canopy closure were measured at weekly intervals. All treatments reached maturity, as measured by NAWF ≤ 5, at approximately the same time during the growing season. Complete canopy closure was delayed in the T3 plots resulting in reduced interception and utilization of available solar radiation early in the growing season. When treatments were initiated, approximately 84% (T1), 62% (T2), and 32% (T3) of the total plant-available water (field capacity less permanent wilting point) was present in the upper 1.5 of the soil profile. Yields were 1263, 1244, and 1110 kg lint ha−1 in 1993 and 1229, 1176, and 1095 kg lint ha −1 in 1994 for T1, T2, and T3, respectively. Lint yields were significantly

  14. Water deficit effects on maize yields modeled under current and greenhouse climates

    International Nuclear Information System (INIS)

    Muchow, R.C.; Sinclair, T.R.

    1991-01-01

    The availability of water imposes one of the major limits on rainfed maize (Zea mays L.) productivity. This analysis was undertaken in an attempt to quantify the effects of limited water on maize growth and yield by extending a simple, mechanistic model in which temperature regulates crop development and intercepted solar radiation is used to calculate crop biomass accumulation. A soil water budget was incorporated into the model by accounting for inputs from rainfall and irrigation, and water use by soil evaporation and crop transpiration. The response functions of leaf area development and crop gas exchange to the soil water budget were developed from experimental studies. The model was used to interpret a range of field experiments using observed daily values of temperature, solar radiation, and rainfall or irrigation, where water deficits of varying durations developed at different stages of growth. The relative simplicity of the model and its robustness in simulating maize yields under a range of water-availability conditions allows the model to be readily used for studies of crop performance under alternate conditions. One such study, presented here, was a yield assessment for rainfed maize under possible greenhouse climates where temperature and atmospheric CO 2 concentration were increased. An increase in temperature combined with decreased rainfall lowered grain yield, although the increase in crop water use efficiency associated with elevated CO 2 concentration ameliorated the response to the greenhouse climate. Grain yields for the greenhouse climates as compared to current conditions increased, or decreased only slightly, except when the greenhouse climate was assumed to result in severly decreased rainfall

  15. Identifying yield-optimizing environments for two cowpea breeding lines by manipulating photoperiod and harvest scenario

    Science.gov (United States)

    Ohler, T. A.; Mitchell, C. A.

    1996-01-01

    Photoperiod and harvest scenario of cowpea (Vigna unguiculata L. Walp) canopies were manipulated to optimize productivity for use in future controlled ecological life-support systems. Productivity was measured by edible yield rate (EYR:g m-2 day-1), shoot harvest index (SHI: g edible biomass [g total shoot dry weight]), and yield-efficiency rate (YER:g edible biomass m-2 day-1 per[g nonedible shoot dry weight]). Breeding lines 'IT84S-2246' (S-2246) and "IT82D-889' (D-889) were grown in a greenhouse under 8-, 12-, or 24-h photoperiods. S-2246 was short-day and D-889 was day-neutral for flowering. Under each photoperiod, cowpeas were harvested either for leaves only, seeds only, or leaves plus seeds (mixed harvest). Photoperiod did not affect EYR of either breeding line for any harvest scenario tested. Averaged over both breeding lines, seed harvest gave the highest EYR at 6.7 g m-2 day-1. The highest SHI (65%) and YER (94 mg m-2 day-1 g-1) were achieved for leaf-only harvest of D-889 under an 8-h photoperiod. For leaf-only harvest of S-2246, both SHI and YER increased with increasing photoperiod, but declined for seed-only and mixed harvests. However, photoperiod had no effect on SHI or YER for D-889 for any harvest scenario. A second experiment utilized the short-day cowpea breeding line 'IT89KD-288' (D-288) and the day-neutral breeding line 'IT87D-941-1' (D-941) to compare yield parameters using photoperiod extension under differing lamp types. This experiment confirmed the photoperiod responses of D-889 and S-2246 to a mixed-harvest scenario and indicated that daylength extension with higher irradiance from high pressure sodium lamps further suppressed EYR, SHI, and YER of the short-day breeding line D-288.

  16. Why do leaf-tying caterpillars abandon their leaf ties?

    Directory of Open Access Journals (Sweden)

    Michelle Sliwinski

    2013-09-01

    Full Text Available Leaf-tying caterpillars act as ecosystem engineers by building shelters between overlapping leaves, which are inhabited by other arthropods. Leaf-tiers have been observed to leave their ties and create new shelters (and thus additional microhabitats, but the ecological factors affecting shelter fidelity are poorly known. For this study, we explored the effects of resource limitation and occupant density on shelter fidelity and assessed the consequences of shelter abandonment. We first quantified the area of leaf material required for a caterpillar to fully develop for two of the most common leaf-tiers that feed on white oak, Quercus alba. On average, Psilocorsis spp. caterpillars consumed 21.65 ± 0.67 cm2 leaf material to complete development. We also measured the area of natural leaf ties found in a Maryland forest, to determine the distribution of resources available to caterpillars in situ. Of 158 natural leaf ties examined, 47% were too small to sustain an average Psilocorsis spp. caterpillar for the entirety of its development. We also manipulated caterpillar densities within experimental ties on potted trees to determine the effects of cohabitants on the likelihood of a caterpillar to leave its tie. We placed 1, 2, or 4 caterpillars in ties of a standard size and monitored the caterpillars twice daily to track their movement. In ties with more than one occupant, caterpillars showed a significantly greater propensity to leave their tie, and left sooner and at a faster rate than those in ties as single occupants. To understand the consequences of leaf tie abandonment, we observed caterpillars searching a tree for a site to build a shelter in the field. This is a risky behavior, as 17% of the caterpillars observed died while searching for a shelter site. Caterpillars that successfully built a shelter traveled 110 ± 20 cm and took 28 ± 7 min to find a suitable site to build a shelter. In conclusion, leaf-tying caterpillars must frequently

  17. A model using marginal efficiency of investment to analyse carbon and nitrogen interactions in forested ecosystems

    Science.gov (United States)

    Thomas, R. Q.; Williams, M.

    2014-12-01

    Carbon (C) and nitrogen (N) cycles are coupled in terrestrial ecosystems through multiple processes including photosynthesis, tissue allocation, respiration, N fixation, N uptake, and decomposition of litter and soil organic matter. Capturing the constraint of N on terrestrial C uptake and storage has been a focus of the Earth System modelling community. Here we explore the trade-offs and sensitivities of allocating C and N to different tissues in order to optimize the productivity of plants using a new, simple model of ecosystem C-N cycling and interactions (ACONITE). ACONITE builds on theory related to plant economics in order to predict key ecosystem properties (leaf area index, leaf C:N, N fixation, and plant C use efficiency) based on the optimization of the marginal change in net C or N uptake associated with a change in allocation of C or N to plant tissues. We simulated and evaluated steady-state and transient ecosystem stocks and fluxes in three different forest ecosystems types (tropical evergreen, temperate deciduous, and temperate evergreen). Leaf C:N differed among the three ecosystem types (temperate deciduous database describing plant traits. Gross primary productivity (GPP) and net primary productivity (NPP) estimates compared well to observed fluxes at the simulation sites. A sensitivity analysis revealed that parameterization of the relationship between leaf N and leaf respiration had the largest influence on leaf area index and leaf C:N. Also, a widely used linear leaf N-respiration relationship did not yield a realistic leaf C:N, while a more recently reported non-linear relationship simulated leaf C:N that compared better to the global trait database than the linear relationship. Overall, our ability to constrain leaf area index and allow spatially and temporally variable leaf C:N can help address challenges simulating these properties in ecosystem and Earth System models. Furthermore, the simple approach with emergent properties based on

  18. Mapped clone and functional analysis of leaf-color gene Ygl7 in a rice hybrid (Oryza sativa L. ssp. indica).

    Science.gov (United States)

    Deng, Xiao-juan; Zhang, Hai-qing; Wang, Yue; He, Feng; Liu, Jin-ling; Xiao, Xiao; Shu, Zhi-feng; Li, Wei; Wang, Guo-huai; Wang, Guo-liang

    2014-01-01

    Leaf-color is an effective marker to identify the hybridization of rice. Leaf-color related genes function in chloroplast development and the photosynthetic pigment biosynthesis of higher plants. The ygl7 (yellow-green leaf 7) is a mutant with spontaneous yellow-green leaf phenotype across the whole lifespan but with no change to its yield traits. We cloned gene Ygl7 (Os03g59640) which encodes a magnesium-chelatase ChlD protein. Expression of ygl7 turns green-leaves to yellow, whereas RNAi-mediated silence of Ygl7 causes a lethal phenotype of the transgenic plants. This indicates the importance of the gene for rice plant. On the other hand, it corroborates that ygl7 is a non-null mutants. The content of photosynthetic pigment is lower in Ygl7 than the wild type, but its light efficiency was comparatively high. All these results indicated that the mutational YGL7 protein does not cause a complete loss of original function but instead acts as a new protein performing a new function. This new function partially includes its preceding function and possesses an additional feature to promote photosynthesis. Chl1, Ygl98, and Ygl3 are three alleles of the OsChlD gene that have been documented previously. However, mutational sites of OsChlD mutant gene and their encoded protein products were different in the three mutants. The three mutants have suppressed grain output. In our experiment, plant materials of three mutants (ygl7, chl1, and ygl98) all exhibited mutational leaf-color during the whole growth period. This result was somewhat different from previous studies. We used ygl7 as female crossed with chl1 and ygl98, respectively. Both the F1 and F2 generation display yellow-green leaf phenotype with their chlorophyll and carotenoid content falling between the values of their parents. Moreover, we noted an important phenomenon: ygl7-NIL's leaf-color is yellow, not yellowy-green, and this is also true of all back-crossed offspring with ygl7.

  19. Mapped clone and functional analysis of leaf-color gene Ygl7 in a rice hybrid (Oryza sativa L. ssp. indica.

    Directory of Open Access Journals (Sweden)

    Xiao-juan Deng

    Full Text Available Leaf-color is an effective marker to identify the hybridization of rice. Leaf-color related genes function in chloroplast development and the photosynthetic pigment biosynthesis of higher plants. The ygl7 (yellow-green leaf 7 is a mutant with spontaneous yellow-green leaf phenotype across the whole lifespan but with no change to its yield traits. We cloned gene Ygl7 (Os03g59640 which encodes a magnesium-chelatase ChlD protein. Expression of ygl7 turns green-leaves to yellow, whereas RNAi-mediated silence of Ygl7 causes a lethal phenotype of the transgenic plants. This indicates the importance of the gene for rice plant. On the other hand, it corroborates that ygl7 is a non-null mutants. The content of photosynthetic pigment is lower in Ygl7 than the wild type, but its light efficiency was comparatively high. All these results indicated that the mutational YGL7 protein does not cause a complete loss of original function but instead acts as a new protein performing a new function. This new function partially includes its preceding function and possesses an additional feature to promote photosynthesis. Chl1, Ygl98, and Ygl3 are three alleles of the OsChlD gene that have been documented previously. However, mutational sites of OsChlD mutant gene and their encoded protein products were different in the three mutants. The three mutants have suppressed grain output. In our experiment, plant materials of three mutants (ygl7, chl1, and ygl98 all exhibited mutational leaf-color during the whole growth period. This result was somewhat different from previous studies. We used ygl7 as female crossed with chl1 and ygl98, respectively. Both the F1 and F2 generation display yellow-green leaf phenotype with their chlorophyll and carotenoid content falling between the values of their parents. Moreover, we noted an important phenomenon: ygl7-NIL's leaf-color is yellow, not yellowy-green, and this is also true of all back-crossed offspring with ygl7.

  20. The effect of leaf litter cover on surface runoff and soil erosion in Northern China.

    Science.gov (United States)

    Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

    2014-01-01

    The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter), four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (prunoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, prunoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h-1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05) were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (prunoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes.

  1. The Effect of Leaf Litter Cover on Surface Runoff and Soil Erosion in Northern China

    Science.gov (United States)

    Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

    2014-01-01

    The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter), four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (prunoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, prunoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h−1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05) were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (prunoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes. PMID:25232858

  2. The effects of vermicompost and chemical fertilizers on yield and yield components of marshmallow (Altheae officinalis L.

    Directory of Open Access Journals (Sweden)

    A.A. Sadeghi

    2016-05-01

    Full Text Available In order to investigate the effects of vermicompost and chemical fertilizers on growth characteristics, yield and yield components of marshmallow (Altheaeofficinalis L., a field experiment was conducted as factorial layout based on a randomized complete block design with three replications at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during growing season of 2012. Experimental treatments were designed based on 3 levels of vermicompost (0, 5 and 10 t ha-1 and 5 levels of nitrogen fertilizer (0, 25, 50, 75 and 100% of 200 kg N ha-1. Results indicated that applied vermicompost had significant effects on increasing leaf area, flower weight per plant and grain yield of marshmallow. Flower weight per plant and grain yield of marshmallow was increased by 2 to 3 times by applying vermicompost at 10 t. ha-1, as compared to control treatment. In addition, nitrogen fertilizer had a significant effect on increasing flower weight per plant and grain, mucilage and oil yields of marshmallow. It seems that applying vermicompost can be suitable strategy in reducing the problems caused by excessive using of chemical fertilizers.

  3. Genotype variation in grain yield response to basal N fertilizer ...

    African Journals Online (AJOL)

    user

    2012-07-24

    Jul 24, 2012 ... identify the variation of grain yield response to basal fertilizer among 199 rice varieties with different genetic background, and finally choose the suitable rice varieties for us to ... proper timing, rate, placement, and use of modified forms ... sowed in seedling-bed with uniform nutritional conditions until 3-leaf.

  4. REVOLUTA and WRKY53 connect early and late leaf development in Arabidopsis

    DEFF Research Database (Denmark)

    Xie, Yakun; Huhn, Kerstin; Brandt, Ronny

    2014-01-01

    As sessile organisms, plants have to continuously adjust growth and development to ever-changing environmental conditions. At the end of the growing season, annual plants induce leaf senescence to reallocate nutrients and energy-rich substances from the leaves to the maturing seeds. Thus, leaf se...... of WRKY53 in response to oxidative stress, and mutations in HD-ZIPIII genes strongly delay the onset of senescence. Thus, a crosstalk between early and late stages of leaf development appears to contribute to reproductive success.......As sessile organisms, plants have to continuously adjust growth and development to ever-changing environmental conditions. At the end of the growing season, annual plants induce leaf senescence to reallocate nutrients and energy-rich substances from the leaves to the maturing seeds. Thus, leaf...... senescence is a means with which to increase reproductive success and is therefore tightly coupled to the developmental age of the plant. However, senescence can also be induced in response to sub-optimal growth conditions as an exit strategy, which is accompanied by severely reduced yield. Here, we show...

  5. Leaf life span plasticity in tropical seedlings grown under contrasting light regimes.

    Science.gov (United States)

    Vincent, Gregoire

    2006-02-01

    The phenotypic plasticity of leaf life span in response to low resource conditions has a potentially large impact on the plant carbon budget, notably in evergreen species not subject to seasonal leaf shedding, but has rarely been well documented. This study evaluates the plasticity of leaf longevity, in terms of its quantitative importance to the plant carbon balance under limiting light. Seedlings of four tropical tree species with contrasting light requirements (Alstonia scholaris, Hevea brasiliensis, Durio zibethinus and Lansium domesticum) were grown under three light regimes (full sunlight, 45 % sunlight and 12 % sunlight). Their leaf dynamics were monitored over 18 months. All species showed a considerable level of plasticity with regard to leaf life span: over the range of light levels explored, the ratio of the range to the mean value of life span varied from 29 %, for the least plastic species, to 84 %, for the most. The common trend was for leaf life span to increase with decreasing light intensity. The plasticity apparent in leaf life span was similar in magnitude to the plasticity observed in specific leaf area and photosynthetic rate, implying that it has a significant impact on carbon gain efficiency when plants acclimate to different light regimes. In all species, median survival time was negatively correlated with leaf photosynthetic capacity (or its proxy, the nitrogen content per unit area) and leaf emergence rate. Longer leaf life spans under low light are likely to be a consequence of slower ageing as a result of a slower photosynthetic metabolism.

  6. Dry matter production, seed yield and water use efficiency of some grain legumes grown under different water regimes using nuclear technique

    International Nuclear Information System (INIS)

    Harb, O.M.S.; Salem, M.S.A.; Abdalla, A.A.; Abd-Elwahed, N.M.

    2007-01-01

    Two field experiments were performed in the experimental farm at the Atomic Energy Authority, Inshas, Egypt, during 2002 and 2004 growing seasons to evaluate the responses of dry matter production, seed yield, water use efficiency and root characteristics for three legumes species, i.e. soybean (Glycine max cv. clark), cowpea (Vigna unguiculata cv. Kafr El-Sheikh) and mungbean (Vigna radiate cv. kawmy 1) grown on a new reclaimed sandy soil under different water regimes. The experiments were laid out using a single line source sprinkler irrigation system which allows a gradual variation of irrigation water, i.e. full irrigation (W1), medium water stress (W2) and severe water stress (W3). The obtained results indicated that normal irrigation (W1) gave the highest above ground dry matter production at flowering stage and total dry matter yield at maturity for the tested legumes. Water stress decreased significantly seed yields for all the tested legume seeds. The seed yield of normal watering condition treatment (W1) out yielded seed yield of those irrigated with medium water stress (W2) and severe water stress (W3). Mungbean and cowpea were more adapted to severe water stress than soybean. Most of the reduction in yield arose from a decrease in pod number. Pod number, number of seeds per pod and the thousand seed weight were significantly affected by water stress. The highest water use efficiency based on seed yield or dry matter yield were obtained by exposing the legume plants to medium water stress (W2), while the lowest value was obtained by exposing the plants to severe water stress (W3). There were significant differences in WUE among the tested species, whereas, mungbean showed the highest value in response to water stress, followed by soybean while cowpea showed the lowest value of water use efficiency. Rooting depth was increased under the severe water stress treatment as compared with well watered condition in the tested legume plants. Mungbean had the

  7. Influence of Plant Growth Regulators (PGRs and Planting Method on Growth and Yield in Oil Pumpkin (Cucurbita pepo var. styriaca

    Directory of Open Access Journals (Sweden)

    Shirzad SURE

    2012-05-01

    Full Text Available The effect of plant growth regulators IBA (indole butyric acid, GA3 (gibberellin and ethylene (as ethephon in two methods of planting was investigated (each method was considered as a separate experiment on morphological characters and yield of medicinal pumpkin. The experiments were carried out in a factorial trial based on completely randomized block design, with four replicates. The treatments were combined with priming and spraying with the above PGRs. The first seed priming with control (water, IBA 100 ppm, GA3 25 ppm and ethephon 200 ppm, and when seedling developed to 4 leaf stage sprayed there with control (water, IBA 100 ppm, GA3 25 ppm and ethephon 200 ppm for three times. In both planting methods, there were all of these treatments. The result showed that PGRs and planting method had significant effects on vegetative, flowering and yield characteristics including: leaf area %DM plant, number of male and female flowers per plant, number of fruit/plant, fruits fresh weight, seeds length and width, number of seed per fruit, seed yield, % seeds oil and oil yield. Hence spraying with GA3 25 ppm in four leaf stage at trellis method could be a suitable treatment for enhancing growth and yield of medicinal pumpkin.

  8. Accumulation and distribution of dry matter in relation to root yield of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-05

    Oct 5, 2009 ... Cassava an important staple food is grown both in upland and inland valley in the tropics. A trial to ... high dry matter also produce high leaf area index and root yield ..... Proportion (%) of DM accumulated in root stock.

  9. (TECTONA GRANDIS LEAF POWDER

    Directory of Open Access Journals (Sweden)

    Yash Mishra

    2015-01-01

    Full Text Available In this study, the adsorption potential of Teak (Tectona grandis leaf powder (TLP toremove Methylene blue (MB and Malachite Green (MG dye molecules from aqueoussolution was investigated. Batch experiments were conducted to evaluate the influenceof operational parameters such as, pH (2−9, adsorbent dosage (1−7 g/L, contact time(15−150 minutes and initial dye concentration (20−120 mg/L at stirring speed of 150rpm for the adsorption of MB and MG on TLP. Maximum removal efficiency of 98.4%and 95.1% was achieved for MB and MG dye, respectively. The experimentalequilibrium data were analysed using Langmuir, Freundlich and Temkin isothermmodels and it was found that, it fitted well to the Freundlich isotherm model. Thesurface structure and morphology of the adsorbent was characterized using scanningelectron microscopy (SEM and the presence of functional groups and its interactionwith the dye molecules were analysed using Fourier transform infrared spectroscopy(FTIR. Based on the investigation, it has been demonstrated that the teak leaf powderhas good potential for effective adsorption of methylene blue and malachite green dye.

  10. Efficient sampling to determine the distribution of fruit quality and yield in a commercial apple orchard

    DEFF Research Database (Denmark)

    Martinez, M.; Wulfsohn, Dvora-Laio; Zamora, I.

    2012-01-01

    In situ assessment of fruit quality and yield can provide critical data for marketing and for logistical planning of the harvest, as well as for site-specific management. Our objective was to develop and validate efficient field sampling procedures for this purpose. We used the previously reported...... 'fractionator' tree sampling procedure and supporting handheld software (Gardi et al., 2007; Wulfsohn et al., 2012) to obtain representative samples of fruit from a 7.6-ha apple orchard (Malus ×domestica 'Fuji Raku Raku') in central Chile. The resulting sample consisted of 70 fruit on 56 branch segments...... of yield. Estimated marketable yield was 295.8±50.2 t. Field and packinghouse records indicated that of 348.2 t sent to packing (52.4 t or 15% higher than our estimate), 263.0 t was packed for export (32.8 t less or -12% error compared to our estimate). The estimated distribution of caliber compared very...

  11. Agrobacterium-Mediated Transformation of Leaf Base Segments.

    Science.gov (United States)

    Gasparis, Sebastian

    2017-01-01

    Agrobacterium-mediated transformation has become a routine method of genetic engineering of cereals, gradually replacing the biolistic protocols. Simple integration patterns of transgenic loci, decent transformation efficiency, and technical simplicity are the main advantages offered by this method. Here we present a detailed protocol for the production of transgenic oat plants by Agrobacterium-mediated transformation of leaf base segments. The use of leaf explants as target tissues for transformation and in vitro regeneration of transgenic plants may be a good alternative for genotypes which are not susceptible to regeneration from immature or mature embryos. We also describe the biochemical and molecular analysis procedures of the transgenic plants including a GUS histochemical assay, and Southern blot, both of which are optimized for application in oat.

  12. Influence of leaf retention on cutting propagation of Lavandula dentata L.

    Directory of Open Access Journals (Sweden)

    Claudine Maria de Bona

    2010-08-01

    Full Text Available Vegetative propagation of lavender offers several advantages over sexual propagation, among them crop homogeneity and yield of higher quality essential oil. However, Lavandula species have been propagated mostly by seeds and are said to be recalcitrant to rooting when propagated by cuttings. During cutting propagation, one of the important variables that influence the rooting capacity of cuttings is the leaf retention. The objective of this work was to evaluate the influence of leaf retention on rooting of L. dentata cuttings. Apical cuttings of L. dentata of 10 cm in length, keeping approximately 1/3, 1/2 or 2/3 of their leaves were planted in commercial substrate Plantmax HT® under intermittent mist. After two months, averages of root number, length of the longest root, root fresh and dry weights, and the survival percentage were evaluated. Root length and fresh weight were statistically greater with 2/3 of leaf retention and when fewer leaves were kept on the cuttings, lower means of root dry weight was observed. Under the conditions applied in this study, greater leaf retention was better for rooting of L. dentata cuttings.

  13. Effects of shade and drought stress on soybean hormones and yield ...

    African Journals Online (AJOL)

    Multiple frequently interactive stress factors naturally influence plant due to global change. The leaf's hormone concentrations, main-stem and branch yield response to the combination of shade and drought were studied in a greenhouse experiment during 2009 and 2010 seasons. Pot experiments were conducted under ...

  14. Alfalfa leaf meal in finishing steer diets. Quarterly report, July 1, 1997--September 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Zehnder, C.M.; DiCostanzo, A.; Smith, L.B.; Brown, D.B.; Hall, J.M.

    1997-10-30

    Ninety-six medium frame, Angus and Angus cross steer calves (average initial weight 540 lb.) were allotted to a heavy or light weight block and then randomly assigned to one of four dietary treatments for a 167 or 189-day finishing phase, respectively. Treatments were control (supplemental soybean meal), alfalfa leaf meal (ALM) providing 33%, 66%, 100% of supplemental protein. Finishing diets were formulated to contain .61 Mcal NE{sub g}/lb dry matter, 12.5% crude protein, .6 % Ca and .3 % P. There were no significant (P >.05) effects of dietary treatments on daily gain or dry matter required /lb of gain. Steers fed 100 % ALM consumed more (P <.05) dry matter than steers fed either of the other three treatments. Dry matter consumption increased linearly (P >.05) with increasing ALM. There was no significant (P >.05) dietary treatment effect on marbling, KPH %, yield grade, quality grade, or liver abscesses. There was an apparent trend in reduced liver abscess incidence in steers fed 100 % ALM. Steers fed 66 % ALM had significantly (P <.05) greater backfat measurements, backfat also had a cubic effect (P <.05). Hot carcass weight had a quadratic relation (P <.05) with level of ALM. Substituting alfalfa leaf meal for soybean meal in diets of finishing steers increased DM intake, but this increase was accompanied by an increase in gain which resulted in similar feed efficiency. There may be an advantage in blending ALM and soybean meal as feed efficiency was improved when cattle were fed the blend. Also, feeding ALM may result in lower incidence of liver abscess.

  15. Silicon Conversion From Bamboo Leaf Silica By Magnesiothermic Reduction for Development of Li-ion Baterry Anode

    Directory of Open Access Journals (Sweden)

    Silviana Silviana

    2018-01-01

    Full Text Available Silicon (Si is a promising alternative material for the anode Lithium ion Battery (LIB. Si has a large theoretical capacity about 3579 mA hg-1, ten times greater than the commercial graphite anode (372 mA hg-1. Bamboo is a source of organic silica (bio-silica. Most part biogenetic content of SiO2 is obtained in bamboo leaves. This paper aims to investigate the synthesis nano Si from bamboo leaves through magnesiothermic reduction after silica extraction using sol–gel method and to observe nano Si of bamboo leaf as mixed material for lithium ion baterry. Silica and silicon content was determined using XRF. Silica product has 96,3 wt. % yield of extraction from bamboo leaf, while silicon yield was obtained 61.2 wt. %. The XRD pattern revealed that silica and silicon product were amourphous. The extracted silica and silicon from bambo leaf has spherical shape and agglomerated form. As anoda material for LIB, silicon product achieved 0,002 mAh capacity for 22 cycle.

  16. Combination of inoculation methods of Azospirilum brasilense with broadcasting of nitrogen fertilizer increases corn yield

    Directory of Open Access Journals (Sweden)

    Tânia Maria Müller

    2015-01-01

    Full Text Available Nitrogen (N is the most limiting nutrient for corn production. Thereby, the goal of the paper was to evaluate inoculation methods of Azospirillum brasilense in order to partially supply N required by the crop. The experiment was carried out in Guarapuava, PR, Brasil, in 2011/2012 growing season. Randomized blocks with factorial 3 inoculation methods (seed treatment, planting furrow and non-inoculated control x 5 doses of nitrogen (0, 75, 150, 225 and 300kg ha-1 x 8 replications was used as the experimental design. Leaf are index, foliar nitrogen content, total chlorophyll, grains per ear and yield were evaluated. There was significant interaction between inoculation methods and nitrogen fertilization to leaf area index, but not for yield. Inoculation with the diazotrophic bacteria provided yield increase of 702kg ha-1 for inoculation in seeding furrow and 432kg ha-1 for inoculation in seed treatment compared to the control, but both treatments did not differ between each other. Furthermore, total chlorophyll, grains per ear and yield were positively affected, with quadratic response, by the nitrogen fertilization in broadcasting

  17. Centrifuge Controlled Shape Tuning of Biosynthesized Gold Nanoparticles Obtained from Plumbago zeylanica Leaf Extract.

    Science.gov (United States)

    Ankamwar, Balaprasad; Pansare, Sachin; Sur, Ujjal Kumar

    2017-02-01

    Development of cost-efficient and eco-friendly biogenic synthetic protocols for the green synthesis of biocompatible metal nanoparticles has become popular among researchers in recent years. The biogenic synthesis of these nanoparticles and their potential biomedical applications introduces the concept of nanobiotechnology, which has become the latest fascinating area of research. The lower cost and lesser side effects as compare to chemical methods of synthesis are the main advantages of biosynthesis. In the present investigation, aqueous leaf extract of Plumbago zeylanica had been used to synthesize anisotropic gold nanoparticles. The as-synthesized gold nanoparticles were centrifuged at 5000 and 10000 rpm and compared both pellets using UV-visible spectroscopy, XRD, FTIR and TEM techniques. We have studied here the effect of speed of centrifugation on the yield, shape, size as well as size distribution of as synthesized gold nanoparticles.

  18. Modelling climate change impacts on viticultural yield, phenology and stress conditions in Europe.

    Science.gov (United States)

    Fraga, Helder; García de Cortázar Atauri, Iñaki; Malheiro, Aureliano C; Santos, João A

    2016-11-01

    Viticulture is a key socio-economic sector in Europe. Owing to the strong sensitivity of grapevines to atmospheric factors, climate change may represent an important challenge for this sector. This study analyses viticultural suitability, yield, phenology, and water and nitrogen stress indices in Europe, for present climates (1980-2005) and future (2041-2070) climate change scenarios (RCP4.5 and 8.5). The STICS crop model is coupled with climate, soil and terrain databases, also taking into account CO 2 physiological effects, and simulations are validated against observational data sets. A clear agreement between simulated and observed phenology, leaf area index, yield and water and nitrogen stress indices, including the spatial differences throughout Europe, is shown. The projected changes highlight an extension of the climatic suitability for grapevines up to 55°N, which may represent the emergence of new winemaking regions. Despite strong regional heterogeneity, mean phenological timings (budburst, flowering, veraison and harvest) are projected to undergo significant advancements (e.g. budburst/harvest can be >1 month earlier), with implications also in the corresponding phenophase intervals. Enhanced dryness throughout Europe is also projected, with severe water stress over several regions in southern regions (e.g. southern Iberia and Italy), locally reducing yield and leaf area. Increased atmospheric CO 2 partially offsets dryness effects, promoting yield and leaf area index increases in central/northern Europe. Future biomass changes may lead to modifications in nitrogen demands, with higher stress in northern/central Europe and weaker stress in southern Europe. These findings are critical decision support systems for stakeholders from the European winemaking sector. © 2016 John Wiley & Sons Ltd.

  19. Effect of progressive drought stress on growth, leaf gas exchange, and antioxidant production in two maize cultivars.

    Science.gov (United States)

    Anjum, Shakeel Ahmad; Tanveer, Mohsin; Ashraf, Umair; Hussain, Saddam; Shahzad, Babar; Khan, Imran; Wang, Longchang

    2016-09-01

    Drought stress is one of the major environmental factors responsible for reduction in crop productivity. In the present study, responses of two maize cultivars (Rung Nong 35 and Dong Dan 80) were examined to explicate the growth, yield, leaf gas exchange, leaf water contents, osmolyte accumulation, membrane lipid peroxidation, and antioxidant activity under progressive drought stress. Maize cultivars were subjected to varying field capacities (FC) viz., well-watered (80 % FC) and drought-stressed (35 % FC) at 45 days after sowing. The effects of drought stress were analyzed at 5, 10, 15, 20, ad 25 days after drought stress (DAS) imposition. Under prolonged drought stress, Rung Nong 35 exhibited higher reduction in growth and yield as compared to Dong Dan 80. Maize cultivar Dong Dan 80 showed higher leaf relative water content (RWC), free proline, and total carbohydrate accumulation than Run Nong 35. Malondialdehyde (MDA) and superoxide anion were increased with prolongation of drought stress, with higher rates in cultivar Run Nong 35 than cultivar Dong Dan 80. Higher production of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) and glutathione reductase (GR) resulted in improved growth and yield in Dong Dan 80. Overall, the cultivar Dong Dan 80 was better able to resist the detrimental effects of progressive drought stress as indicated by better growth and yield due to higher antioxidant enzymes, reduced lipid peroxidation, better accumulation of osmolytes, and maintenance of tissue water contents.

  20. Effect of Moringa oleifera leaf meal on finisher pig growth ...

    African Journals Online (AJOL)

    Effect of Moringa oleifera leaf meal on finisher pig growth performance, meat ... pig growth performance, meat quality, shelf life and fatty acid composition of pork ... negative effect on feed conversion efficiency, carcass and meat quality traits, ...

  1. Can Leaf Spectroscopy Predict Leaf and Forest Traits Along a Peruvian Tropical Forest Elevation Gradient?

    Science.gov (United States)

    Doughty, Christopher E.; Santos-Andrade, P. E.; Goldsmith, G. R.; Blonder, B.; Shenkin, A.; Bentley, L. P.; Chavana-Bryant, C.; Huaraca-Huasco, W.; Díaz, S.; Salinas, N.; Enquist, B. J.; Martin, R.; Asner, G. P.; Malhi, Y.

    2017-11-01

    High-resolution spectroscopy can be used to measure leaf chemical and structural traits. Such leaf traits are often highly correlated to other traits, such as photosynthesis, through the leaf economics spectrum. We measured VNIR (visible-near infrared) leaf reflectance (400-1,075 nm) of sunlit and shaded leaves in 150 dominant species across ten, 1 ha plots along a 3,300 m elevation gradient in Peru (on 4,284 individual leaves). We used partial least squares (PLS) regression to compare leaf reflectance to chemical traits, such as nitrogen and phosphorus, structural traits, including leaf mass per area (LMA), branch wood density and leaf venation, and "higher-level" traits such as leaf photosynthetic capacity, leaf water repellency, and woody growth rates. Empirical models using leaf reflectance predicted leaf N and LMA (r2 > 30% and %RMSE < 30%), weakly predicted leaf venation, photosynthesis, and branch density (r2 between 10 and 35% and %RMSE between 10% and 65%), and did not predict leaf water repellency or woody growth rates (r2<5%). Prediction of higher-level traits such as photosynthesis and branch density is likely due to these traits correlations with LMA, a trait readily predicted with leaf spectroscopy.

  2. Contributions of leaf photosynthetic capacity, leaf angle and self-shading to the maximization of net photosynthesis in Acer saccharum: a modelling assessment.

    Science.gov (United States)

    Posada, Juan M; Sievänen, Risto; Messier, Christian; Perttunen, Jari; Nikinmaa, Eero; Lechowicz, Martin J

    2012-08-01

    Plants are expected to maximize their net photosynthetic gains and efficiently use available resources, but the fundamental principles governing trade-offs in suites of traits related to resource-use optimization remain uncertain. This study investigated whether Acer saccharum (sugar maple) saplings could maximize their net photosynthetic gains through a combination of crown structure and foliar characteristics that let all leaves maximize their photosynthetic light-use efficiency (ε). A functional-structural model, LIGNUM, was used to simulate individuals of different leaf area index (LAI(ind)) together with a genetic algorithm to find distributions of leaf angle (L(A)) and leaf photosynthetic capacity (A(max)) that maximized net carbon gain at the whole-plant level. Saplings grown in either the open or in a forest gap were simulated with A(max) either unconstrained or constrained to an upper value consistent with reported values for A(max) in A. saccharum. It was found that total net photosynthetic gain was highest when whole-plant PPFD absorption and leaf ε were simultaneously maximized. Maximization of ε required simultaneous adjustments in L(A) and A(max) along gradients of PPFD in the plants. When A(max) was constrained to a maximum, plants growing in the open maximized their PPFD absorption but not ε because PPFD incident on leaves was higher than the PPFD at which ε(max) was attainable. Average leaf ε in constrained plants nonetheless improved with increasing LAI(ind) because of an increase in self-shading. It is concluded that there are selective pressures for plants to simultaneously maximize both PPFD absorption at the scale of the whole individual and ε at the scale of leaves, which requires a highly integrated response between L(A), A(max) and LAI(ind). The results also suggest that to maximize ε plants have evolved mechanisms that co-ordinate the L(A) and A(max) of individual leaves with PPFD availability.

  3. A flux-based assessment of the effects of ozone on foliar injury, photosynthesis, and yield of bean (Phaseolus vulgaris L. cv. Borlotto Nano Lingua di Fuoco) in open-top chambers

    Energy Technology Data Exchange (ETDEWEB)

    Gerosa, Giacomo [Department of Mathematics and Physics, Universita Cattolica del Sacro Cuore, via dei Musei 41, 20125 Brescia (Italy); Marzuoli, Riccardo [Department of Mathematics and Physics, Universita Cattolica del Sacro Cuore, via dei Musei 41, 20125 Brescia (Italy); Fondazione Lombardia per l' Ambiente, piazza Diaz 9, 20123 Milano (Italy); Rossini, Micol; Panigada, Cinzia; Meroni, Michele; Colombo, Roberto [Remote Sensing of Environmental Dynamics Lab., DISAT, University of Milano-Bicocca, Piazza della Scienza 1, 20126 Milano (Italy); Faoro, Franco [Plant Pathology Institute, Universita di Milano, via Celoria 2, 20133 Milano (Italy); Iriti, Marcello, E-mail: marcello.iriti@unimi.i [Plant Pathology Institute, Universita di Milano, via Celoria 2, 20133 Milano (Italy)

    2009-05-15

    Stomatal ozone uptake, determined with the Jarvis' approach, was related to photosynthetic efficiency assessed by chlorophyll fluorescence and reflectance measurements in open-top chamber experiments on Phaseolus vulgaris. The effects of O{sub 3} exposure were also evaluated in terms of visible and microscopical leaf injury and plant productivity. Results showed that microscopical leaf symptoms, assessed as cell death and H{sub 2}O{sub 2} accumulation, preceded by 3-4 days the appearance of visible symptoms. An effective dose of ozone stomatal flux for visible leaf damages was found around 1.33 mmol O{sub 3} m{sup -2}. Significant linear dose-response relationships were obtained between accumulated fluxes and optical indices (PRI, NDI, DELTAF/F{sub m}{sup '}). The negative effects on photosynthesis reduced plant productivity, affecting the number of pods and seeds, but not seed weight. These results, besides contributing to the development of a flux-based ozone risk assessment for crops in Europe, highlight the potentiality of reflectance measurements for the early detection of ozone stress. - Ozone stomatal fluxes affect leaf cell viability, photosynthetic performance, optical properties and crop yield of bean.

  4. Adventitious shoot regeneration from leaf explants of the valuable ...

    African Journals Online (AJOL)

    The objective of this study was to develop an efficient protocol for adventitious shoot regeneration for Plectranthus barbatus Andrews using leaf explants. The explants were cultured on MS (Murashige and Skoog, 1962) medium containing various concentration of kinetin (KN), 6-benzylaminopurine (BAP) and thidiazuron ...

  5. Effect of Fungicide Applications on Grain Sorghum (Sorghum bicolor L. Growth and Yield

    Directory of Open Access Journals (Sweden)

    Dan D. Fromme

    2017-01-01

    Full Text Available Field studies were conducted in the upper Texas Gulf Coast and in central Louisiana during the 2013 through 2015 growing seasons to evaluate the effects of fungicides on grain sorghum growth and development when disease pressure was low or nonexistent. Azoxystrobin and flutriafol at 1.0 L/ha and pyraclostrobin at 0.78 L/ha were applied to the plants of two grain sorghum hybrids (DKS 54-00, DKS 53-67 at 25% bloom and compared with the nontreated check for leaf chlorophyll content, leaf temperature, and plant lodging during the growing season as well as grain mold, test weight, yield, and nitrogen and protein content of the harvested grain. The application of a fungicide had no effect on any of the variables tested with grain sorghum hybrid responses noted. DKS 53-67 produced higher yield, greater test weight, higher percent protein, and N than DKS 54-00. Results of this study indicate that the application of a fungicide when little or no disease is present does not promote overall plant health or increase yield.

  6. Leaf size and leaf display of thirty-eight tropical tree species

    NARCIS (Netherlands)

    Poorter, L.; Rozendaal, D.M.A.

    2008-01-01

    Trees forage for light through optimal leaf display. Effective leaf display is determined by metamer traits (i.e., the internode, petiole, and corresponding leaf), and thus these traits strongly co-determine carbon gain and as a result competitive advantage in a light-limited environment. We

  7. Comparison of RNA Extraction Methods for the Identification of Grapevine fan leaf virus

    Directory of Open Access Journals (Sweden)

    Z. Gholampour

    2016-06-01

    Full Text Available Introduction: To now, more than 70 viral diseases have been reported from grapevine. Serological methods are regular diagnostic tools of grapevine viruses, however, their sensitivity has affected by seasonal fluctuations of the virus. Reverse transcription polymerase chain reaction provides significant improvement in detection of grapevine viruses. Extraction of high-quality RNA is essential for the successful application of many molecular techniques, such as RT-PCR. Extraction of high-quality RNA from the leaves of woody plants, such as grapevine, is particularly challenging because of high concentrations of polysaccharides, polyphenols, and other secondary metabolites. Some RNA extraction methods yield pellets that are poorly soluble, indicating the presence of unknown contaminants, whereas others are gelatinous, indicating the presence of polysaccharides. RNA can make complexes with polysaccharides and phenolic compounds render the RNA unusable for applications such as reverse transcription. Grapevine fanleaf virus is a member of the genus Nepovirus in the family Secoviridae. The GFLV genome consists of two positive-sense single stranded RNAs. The genome has a poly (A tail at the 3´ terminus and a covalently linked VPG protein at the 5´ terminus. Several extraction methods had been reported to be used for identification of GFLV in grapevine. Some of them require harmful chemical material; disadvantages of other are high costs. Immunocapture-RT-PCR requires preparation of specific antibody and direct binding RT-PCR (DB-RT-PCR has a high contamination risk. In this study, four RNA extraction protocols were compared with a commercial isolation kit to explore the most efficient RNA isolation method for grapevines. Material and Methods: 40 leaf samples were randomly collected during the growing season of 2011-2012. GFLV was detected in leaf samples by enzyme linked immunosorbent assay (ELISA Using specific antibodies raised against Iranian

  8. Dairy cows fed on tropical legume forages: effects on milk yield, nutrients use efficiency and profitability.

    Science.gov (United States)

    Castro-Montoya, J M; García, R A; Ramos, R A; Flores, J M; Alas, E A; Corea, E E

    2018-04-01

    Two trials with multiparous dairy cows were conducted. Experiment 1 tested the effects of increasing forage proportion in the diet (500, 600, and 700 g/kg DM) when a mixed sorghum (Sorghum bicolor) and jackbean (Cannavalia ensiformis) silage was used as forage. Experiment 2 studied the substitution of sorghum silage and soybean meal by jackbean silage or fresh cowpea (Vigna unguiculata) forage in the diet. All diets were iso-energetic and iso-proteic. In each experiment, 30 cows were used and separated into three groups. In experiment 1, there were no differences in dry matter intake (DMI), milk yield (MY), or apparent total tract digestibility (aTTd) among the three diets, but milk fat content increased with increasing forage proportion, even though the similar neutral detergent fiber of all diets. Nitrogen use efficiency was highest in the diet containing 600 g forage/kg DM, and some evidence was observed for a better profitability with this forage proportion. In experiment 2, feeding legumes increased DMI despite no effects on aTTd. Milk yield increased in line with DMI, with a larger increase for the fresh cowpea. Nitrogen use efficiency and milk composition were not affected by the diets. The increased MY and lower feed costs increased the economic benefits when feeding legumes, particularly when feeding fresh cowpea. Feeding fresh cowpea or jackbean silage to dairy cows appears to be an alternative to soybean as protein source, ideally at a forage proportions of 600 g/kg DM, without altering milk yield and quality and increasing the farm profitability.

  9. Lateral Penumbra Modelling Based Leaf End Shape Optimization for Multileaf Collimator in Radiotherapy

    Directory of Open Access Journals (Sweden)

    Dong Zhou

    2016-01-01

    Full Text Available Lateral penumbra of multileaf collimator plays an important role in radiotherapy treatment planning. Growing evidence has revealed that, for a single-focused multileaf collimator, lateral penumbra width is leaf position dependent and largely attributed to the leaf end shape. In our study, an analytical method for leaf end induced lateral penumbra modelling is formulated using Tangent Secant Theory. Compared with Monte Carlo simulation and ray tracing algorithm, our model serves well the purpose of cost-efficient penumbra evaluation. Leaf ends represented in parametric forms of circular arc, elliptical arc, Bézier curve, and B-spline are implemented. With biobjective function of penumbra mean and variance introduced, genetic algorithm is carried out for approximating the Pareto frontier. Results show that for circular arc leaf end objective function is convex and convergence to optimal solution is guaranteed using gradient based iterative method. It is found that optimal leaf end in the shape of Bézier curve achieves minimal standard deviation, while using B-spline minimum of penumbra mean is obtained. For treatment modalities in clinical application, optimized leaf ends are in close agreement with actual shapes. Taken together, the method that we propose can provide insight into leaf end shape design of multileaf collimator.

  10. Lateral Penumbra Modelling Based Leaf End Shape Optimization for Multileaf Collimator in Radiotherapy

    Science.gov (United States)

    Zhou, Dong; Zhang, Hui; Ye, Peiqing

    2016-01-01

    Lateral penumbra of multileaf collimator plays an important role in radiotherapy treatment planning. Growing evidence has revealed that, for a single-focused multileaf collimator, lateral penumbra width is leaf position dependent and largely attributed to the leaf end shape. In our study, an analytical method for leaf end induced lateral penumbra modelling is formulated using Tangent Secant Theory. Compared with Monte Carlo simulation and ray tracing algorithm, our model serves well the purpose of cost-efficient penumbra evaluation. Leaf ends represented in parametric forms of circular arc, elliptical arc, Bézier curve, and B-spline are implemented. With biobjective function of penumbra mean and variance introduced, genetic algorithm is carried out for approximating the Pareto frontier. Results show that for circular arc leaf end objective function is convex and convergence to optimal solution is guaranteed using gradient based iterative method. It is found that optimal leaf end in the shape of Bézier curve achieves minimal standard deviation, while using B-spline minimum of penumbra mean is obtained. For treatment modalities in clinical application, optimized leaf ends are in close agreement with actual shapes. Taken together, the method that we propose can provide insight into leaf end shape design of multileaf collimator. PMID:27110274

  11. Lateral Penumbra Modelling Based Leaf End Shape Optimization for Multileaf Collimator in Radiotherapy.

    Science.gov (United States)

    Zhou, Dong; Zhang, Hui; Ye, Peiqing

    2016-01-01

    Lateral penumbra of multileaf collimator plays an important role in radiotherapy treatment planning. Growing evidence has revealed that, for a single-focused multileaf collimator, lateral penumbra width is leaf position dependent and largely attributed to the leaf end shape. In our study, an analytical method for leaf end induced lateral penumbra modelling is formulated using Tangent Secant Theory. Compared with Monte Carlo simulation and ray tracing algorithm, our model serves well the purpose of cost-efficient penumbra evaluation. Leaf ends represented in parametric forms of circular arc, elliptical arc, Bézier curve, and B-spline are implemented. With biobjective function of penumbra mean and variance introduced, genetic algorithm is carried out for approximating the Pareto frontier. Results show that for circular arc leaf end objective function is convex and convergence to optimal solution is guaranteed using gradient based iterative method. It is found that optimal leaf end in the shape of Bézier curve achieves minimal standard deviation, while using B-spline minimum of penumbra mean is obtained. For treatment modalities in clinical application, optimized leaf ends are in close agreement with actual shapes. Taken together, the method that we propose can provide insight into leaf end shape design of multileaf collimator.

  12. Root morphology, hydraulic conductivity and plant water relations of high-yielding rice grown under aerobic conditions.

    Science.gov (United States)

    Kato, Yoichiro; Okami, Midori

    2011-09-01

    Increasing physical water scarcity is a major constraint for irrigated rice (Oryza sativa) production. 'Aerobic rice culture' aims to maximize yield per unit water input by growing plants in aerobic soil without flooding or puddling. The objective was to determine (a) the effect of water management on root morphology and hydraulic conductance, and (b) their roles in plant-water relationships and stomatal conductance in aerobic culture. Root system development, stomatal conductance (g(s)) and leaf water potential (Ψ(leaf)) were monitored in a high-yielding rice cultivar ('Takanari') under flooded and aerobic conditions at two soil moisture levels [nearly saturated (> -10 kPa) and mildly dry (> -30 kPa)] over 2 years. In an ancillary pot experiment, whole-plant hydraulic conductivity (soil-leaf hydraulic conductance; K(pa)) was measured under flooded and aerobic conditions. Adventitious root emergence and lateral root proliferation were restricted even under nearly saturated conditions, resulting in a 72-85 % reduction in total root length under aerobic culture conditions. Because of their reduced rooting size, plants grown under aerobic conditions tended to have lower K(pa) than plants grown under flooded conditions. Ψ(leaf) was always significantly lower in aerobic culture than in flooded culture, while g(s) was unchanged when the soil moisture was at around field capacity. g(s) was inevitably reduced when the soil water potential at 20-cm depth reached -20 kPa. Unstable performance of rice in water-saving cultivations is often associated with reduction in Ψ(leaf). Ψ(leaf) may reduce even if K(pa) is not significantly changed, but the lower Ψ(leaf) would certainly occur in case K(pa) reduces as a result of lower water-uptake capacity under aerobic conditions. Rice performance in aerobic culture might be improved through genetic manipulation that promotes lateral root branching and rhizogenesis as well as deep rooting.

  13. Efficient Return Algorithms For Associated Plasticity With Multiple Yield Planes

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars; Andersen, Lars

    2006-01-01

    of such criteria. The return formulae are in closed form and no iteration is required. The method accounts for three types of stress return: Return to a single yield plane, to a discontinuity line at the intersection of two yield planes and to a discontinuity point at the intersection between three or more yield...... planes. The infinitesimal and the consistent elastoplastic constitutive matrix are calculated for each type of stress return, as are the conditions to ascertain which type of return is required. The method is exemplified with the Mohr-Coulomb yield criterion....

  14. Quality improvement by batch vacuum distillation and physicochemical characterization of clove leaf oil in Central Java, Indonesia

    Science.gov (United States)

    Alighiri, D.; Eden, W. T.; Cahyono, E.; Supardi, K. I.

    2018-03-01

    Clove leaf oil is one of the essential oils which have high economic value and produced in considerable amount in Indonesia. As many as 60% of clove oil produced by Indonesia has exported to many countries in the world. Musuk and Ringinlarik Village, Boyolali District, Central Java Province is one of the areas in Indonesia which became the primary supplier of Indonesian clove leaf oil. Although, the quality of the resulting yield is still low because it uses a simple distillation kettle in the form of the iron plate or used the drum. The clove leaf oil produced by steam distillation from the dry whole leaves of the clove tree. The color of the oil is brownish black and dirty with the odor are fresh distilled, spicy, warm, and terpenic. The specific gravity at 25 °C of 1.529, the refractive index at 20 °C of 1.030, and based on GC-MS analysis, eugenol levels only 68% and caryophyllene is too high, i.e., 20%. The quality of clove leaf oil produced does not meet the specifications of international market standards. This work aimed to improve the quality of Indonesian clove leaf oil. The purifications done in this research was used by batch vacuum distillation with mode operation at vacuum -76 cmHg and reflux ratios 5:1. Clove leaf oil produced by using this method has a better physicochemical characterization, i.e., the appearance that is yellow to pale color with the odor is spicy, woody, warm, and terpenic. The specific gravity at 25 °C of 1.533, the refractive index at 20 °C of 1.038, and eugenol and caryophyllene contents has yielded 80.58% and 10%, respectively. By The enhancement quality of clove leaf oil by batch vacuum distillation, these oil is already meet international standards and income of clove leaf oil grower in Musuk and Ringinlarik Village, Boyolali District, Central Java Province, Indonesia could be increased.

  15. Evaluation of Methane from Sisal Leaf Residue and Palash Leaf Litter

    Science.gov (United States)

    Arisutha, S.; Baredar, P.; Deshpande, D. M.; Suresh, S.

    2014-12-01

    The aim of this study is to evaluate methane production from sisal leaf residue and palash leaf litter mixed with different bulky materials such as vegetable market waste, hostel kitchen waste and digested biogas slurry in a laboratory scale anaerobic reactor. The mixture was prepared with 1:1 proportion. Maximum methane content of 320 ml/day was observed in the case of sisal leaf residue mixed with vegetable market waste as the feed. Methane content was minimum (47 ml/day), when palash leaf litter was used as feed. This was due to the increased content of lignin and polyphenol in the feedstock which were of complex structure and did not get degraded directly by microorganisms. Sisal leaf residue mixtures also showed highest content of volatile fatty acids (VFAs) as compared to palash leaf litter mixtures. It was observed that VFA concentration in the digester first increased, reached maximum (when pH was minimum) and then decreased.

  16. Effect of weed control treatments on total leaf area of plantation black walnut (Juglans nigra)

    Science.gov (United States)

    Jason Cook; Michael R. Saunders

    2013-01-01

    Determining total tree leaf area is necessary for describing tree carbon balance, growth efficiency, and other measures used in tree-level and stand-level physiological growth models. We examined the effects of vegetation control methods on the total leaf area of sapling-size plantation black walnut trees using allometric approaches. We found significant differences in...

  17. Leaf development and demography explain photosynthetic seasonality in Amazon evergreen forests

    Science.gov (United States)

    Wu, Jin; Albert, Lauren; Lopes, Aline; Restrepo-Coupe, Natalia; Hayek, Matthew; Wiedemann, Kenia T.; Guan, Kaiyu; Stark, Scott C.; Christoffersen, Bradley; Prohaska, Neill; Tavares, Julia V.; Marostica, Suelen; Kobayashi, Hideki; Ferreira, Maurocio L.; Campos, Kleber Silva; da Silva, Rodrigo; Brando, Paulo M.; Dye, Dennis G.; Huxman, Travis E.; Huete, Alfredo; Nelson, Bruce; Saleska, Scott

    2016-01-01

    In evergreen tropical forests, the extent, magnitude, and controls on photosynthetic seasonality are poorly resolved and inadequately represented in Earth system models. Combining camera observations with ecosystem carbon dioxide fluxes at forests across rainfall gradients in Amazônia, we show that aggregate canopy phenology, not seasonality of climate drivers, is the primary cause of photosynthetic seasonality in these forests. Specifically, synchronization of new leaf growth with dry season litterfall shifts canopy composition toward younger, more light-use efficient leaves, explaining large seasonal increases (~27%) in ecosystem photosynthesis. Coordinated leaf development and demography thus reconcile seemingly disparate observations at different scales and indicate that accounting for leaf-level phenology is critical for accurately simulating ecosystem-scale responses to climate change.

  18. Lifetime return on investment increases with leaf lifespan among 10 Australian woodland species.

    Science.gov (United States)

    Falster, Daniel S; Reich, Peter B; Ellsworth, David S; Wright, Ian J; Westoby, Mark; Oleksyn, Jacek; Lee, Tali D

    2012-01-01

    • Co-occurring species often differ in their leaf lifespan (LL) and it remains unclear how such variation is maintained in a competitive context. Here we test the hypothesis that leaves of long-LL species yield a greater return in carbon (C) fixed per unit C or nutrient invested by the plant than those of short-LL species. • For 10 sympatric woodland species, we assessed three-dimensional shoot architecture, canopy openness, leaf photosynthetic light response, leaf dark respiration and leaf construction costs across leaf age sequences. We then used the YPLANT model to estimate light interception and C revenue along the measured leaf age sequences. This was done under a series of simulations that incorporated the potential covariates of LL in an additive fashion. • Lifetime return in C fixed per unit C, N or P invested increased with LL in all simulations. • In contrast to other recent studies, our results show that extended LL confers a fundamental economic advantage by increasing a plant's return on investment in leaves. This suggests that time-discounting effects, that is, the compounding of income that arises from quick reinvestment of C revenue, are key in allowing short-LL species to succeed in the face of this economic handicap. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  19. Despina Hatzifotiadou: ALICE Master Class 3 - Theory: strangeness enhancement; centrality of lead-lead collisions; efficiency, yield, background etc

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    This is the 3rd of 4 short online videos. It explains what is: strangeness enhancement; centrality of lead-lead collisions; efficiency, yield, background etc. More details and related links on this indico event page. In more detail: What is Physics Master Classes Students after morning lectures, run programmes in the afternoon to do measurements. These tutorials are about how to use the software required to do these measurements. Background info and examples  Looking for strange particles with ALICE http://aliceinfo.cern.ch/Public/MasterCL/MasterClassWebpage.html Introduction to first part of the exercise : what are strange particles, V0 decays, invariant mass. Demonstration of the software for the 1st part of the exercise - visual identification of V0s Introduction to second part of the exercise : strangeness enhancement; centrality of lead-lead collisions; explanation of efficiency, yield, background etc Demonstration of the software for the 2nd part of the exercise - invariant mass spectr...

  20. ‘Breath figures’ on leaf surfaces – formation and effects of microscopic leaf wetness

    Directory of Open Access Journals (Sweden)

    Jürgen eBurkhardt

    2013-10-01

    Full Text Available ‘Microscopic leaf wetness’ means minute amounts of persistent liquid water on leaf surfaces which are invisible to the naked eye. The water is mainly maintained by transpired water vapor condensing onto the leaf surface and to attached leaf surface particles. With an estimated average thickness of less than 1 µm, microscopic leaf wetness it is about 2 orders of magnitude thinner than morning dewfall. The most important physical processes which reduce the saturation vapor pressure and promote condensation are cuticular absorption and the deliquescence of hygroscopic leaf surface particles. Deliquescent salts form highly concentrated solutions. Depending on the amount and concentration of the dissolved ions, the physicochemical properties of microscopic leaf wetness can be considerably different from those of pure water. Microscopic leaf wetness can form continuous thin layers on hydrophobic leaf surfaces and in specific cases can act similar to surfactants, enabling a strong potential influence on the foliar exchange of ions. Microscopic leaf wetness can also enhance the dissolution, the emission, and the reaction of specific atmospheric trace gases e.g. ammonia, SO2, or ozone, leading to a strong potential role for microscopic leaf wetness in plant/atmosphere interaction. Due to its difficult detection, there is little knowledge about the occurrence and the properties of microscopic leaf wetness. However, based on the existing evidence and on physicochemical reasoning it can be hypothesized that microscopic leaf wetness occurs on almost any plant worldwide and often permanently, and that it significantly influences the exchange processes of the leaf surface with its neighboring compartments, i.e., the plant interior and the atmosphere. The omission of microscopic water in general leaf wetness concepts has caused far-reaching, misleading conclusions in the past.

  1. Contrasting water-use efficiency (WUE) responses of a potato mapping population and capability of modified ball-berry model to predict stomatal conductance and WUE measured at different environmental conditions

    DEFF Research Database (Denmark)

    Kaminski, Kacper Piotr; Kørup, Kirsten; Kristensen, K.

    2015-01-01

    Potatoes (Solanum tuberosum L.) are drought-sensitive and more efficient water use, while maintaining high yields is required. Here, water-use efficiency (WUE) of a mapping population comprising 144 clones from a cross between 90-HAF-01 (Solanum tuberosum1) and 90-HAG-15 (S. tuberosum2 × S....... sparsipilum) was measured on well-watered plants under controlled-environment conditions combining three levels of each of the factors: [CO2], temperature, light, and relative humidity in growth chambers. The clones were grouped according to their photosynthetic WUE (pWUE) and whole-plant WUE (wpWUE) during...... (34 %) and dry matter accumulation (55 %, P water use (16 %). The pWUE correlated negatively to the ratio between leaf-internal and leaf-external [CO2] (R2 = -0.86 in 2010 and R2 = -0.83 in 2011, P

  2. Evaluation of Chitosan Nanoparticles Effects on Yield and Yield Components of Barley (Hordeum vulgare L. under Late Season Drought Stress

    Directory of Open Access Journals (Sweden)

    Faride Behboudi

    2018-01-01

    Full Text Available As a step towards the profitable employment of nanoparticles (NPs in agriculture, effects of chitosan NPs was probed on barley plants under late season drought stress. A factorial experiment was performed based on a randomized complete block design with three replications. The experimental factors included the chitosan NPs concentrations (0 (control, 30, 60 and 90 ppm, application methods (foliar and soil application and irrigation regimes (well-watered and withholding of irrigation for 15 days after pollination. The barley seeds were separately planted in pots. Then, the NPs were added to them through the soil and foliar application at three stages. The results indicated that using the chitosan NPs, especially 60 and 90 ppm, significantly increased the leaf area (LA, the leaf color (SPAD, the number of grain per spike, the grain yield and the harvest index compared to the control. Also, drought stress significantly decreased the yield and yield components compared to the well-watered plants. In contrast, using the chitosan NPs in plants under drought stress significantly increased the relative water content (RWC, the 1000-grain weight, the grain protein, the proline content, the catalase (CAT and the superoxide dismutase (SOD compared to the control. There was no a significant difference between two methods of using NPs in most studied traits. The results highlighted that using the chitosan NPs, especially 60 and 90 ppm, in both irrigation regimes can significantly improve the majority of the studied traits compared to the control and mitigate the harmful effects of drought stress.

  3. FOLIAR NUTRIENT CONTENTS AND FRUIT YIELD IN CUSTARD APPLE PROGENIES

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio Lima e Silva

    2009-01-01

    Full Text Available Foliar nutrient contents are evaluated in several fruit trees with many objectives. Leaf analysis constitutes a way of evaluating the nutritional requirements of crops. Due to the positive impact that fertilizers have on crop yields, researchers frequently try to evaluate the correlations between yield and foliar nutrient contents. This work's objective was to present fruit yields from the 4th to the 6th cropping seasons, evaluate foliar nutrient contents (on the 5th cropping season, and estimate the correlations between these two groups of traits for 20 half-sibling custard apple tree progenies. The progenies were evaluated in a random block design with five replicates and four plants per plot. One hundred leaves were collected from the middle third of the canopy (in height of each of four plants in each plot. The leaves were collected haphazardly, i.e., in a random manner, but without using a drawing mechanism. In the analysis of variance, the nutrient concentrations in the leaves from plants of each plot were represented by the average of four plants in the plot. Fruit yield in the various progenies did not depend on cropping season; progeny A4 was the most productive. No Spearman correlation was found between leaf nutrient concentrations and fruit yield. Increased nutrient concentrations in the leaves were progeny-dependent, i.e., with regard to Na (progenies FE5 and JG1, Ca (progeny A4, Mg (progeny SM7, N (progeny A3, P (progeny M, and K contents (progeny JG3. Spearman's correlation was negative between Na-Mg, Na-Ca, and Mg-P contents, and positive between Mg-Ca and N-K contents.

  4. Predicting vegetation type through physiological and environmental interactions with leaf traits: evergreen and deciduous forests in an earth system modeling framework.

    Science.gov (United States)

    Weng, Ensheng; Farrior, Caroline E; Dybzinski, Ray; Pacala, Stephen W

    2017-06-01

    Earth system models are incorporating plant trait diversity into their land components to better predict vegetation dynamics in a changing climate. However, extant plant trait distributions will not allow extrapolations to novel community assemblages in future climates, which will require a mechanistic understanding of the trade-offs that determine trait diversity. In this study, we show how physiological trade-offs involving leaf mass per unit area (LMA), leaf lifespan, leaf nitrogen, and leaf respiration may explain the distribution patterns of evergreen and deciduous trees in the temperate and boreal zones based on (1) an evolutionary analysis of a simple mathematical model and (2) simulation experiments of an individual-based dynamic vegetation model (i.e., LM3-PPA). The evolutionary analysis shows that these leaf traits set up a trade-off between carbon- and nitrogen-use efficiency at the scale of individual trees and therefore determine competitively dominant leaf strategies. As soil nitrogen availability increases, the dominant leaf strategy switches from one that is high in nitrogen-use efficiency to one that is high in carbon-use efficiency or, equivalently, from high-LMA/long-lived leaves (i.e., evergreen) to low-LMA/short-lived leaves (i.e., deciduous). In a region of intermediate soil nitrogen availability, the dominant leaf strategy may be either deciduous or evergreen depending on the initial conditions of plant trait abundance (i.e., founder controlled) due to feedbacks of leaf traits on soil nitrogen mineralization through litter quality. Simulated successional patterns by LM3-PPA from the leaf physiological trade-offs are consistent with observed successional dynamics of evergreen and deciduous forests at three sites spanning the temperate to boreal zones. © 2016 John Wiley & Sons Ltd.

  5. Rice yield as a function of transplanting data using historic weather data from the Philippines

    International Nuclear Information System (INIS)

    Centeno, H.A.; Aclan, A.P.; Kropff, M.J.; Cassman, K.G.

    1993-01-01

    Crop yield potential differs among environments in different years, and between seasons in the same year. Under good farm management with ample supply of water and nutrients, and without any pests and diseases, cultivar characteristics, temperature and solar radiation determine the potential yield of a crop. In 1992, 12-day old seedlings of rice (Oryza sativa L.) cv IR72 were transplanted at IRRI [International Rice Research Inst., Los Banos, Laguna, Philippines] farm under irrigated conditions. Highest nitrogen input was 110 kg N/ha during the wet season (WS) and 225 kg N/ha in the dry season (DS). Nitrogen inputs in the wet season were lower to avoid lodging and to match crop N requirements. In both seasons, detailed measurements were obtained for a quantitative understanding of the determinants of rice yield potential. The eco-physiological growth model (ORYZA1) accurately simulated observed yields in the wet and dry seasons (6 and 9.5 t/ha, respectively). The model was used to simulate yields with different planting dates, using historic weather data from selected sites in the Philippines. Rice yield was simulated using leaf nitrogen levels measured in WS and DS experiments. In Los Banos, the highest yields were obtained when the crop was transplanted in December. When the leaf nitrogen measurements from the 1992 dry season experiment were incorporated in the model, predicted yield was higher throughout the year, with the effect more pronounced during the dry season

  6. GROWTH, PHYSIOLOGY AND YIELD OF FORMOSA ‘PAPAYA’ CULTIVATED UNDER DIFFERENT DOSES OF COATED AND CONVENTIONAL UREA

    Directory of Open Access Journals (Sweden)

    GABRIEL BARBOSA DA SILVA JÚNIOR

    2016-01-01

    Full Text Available Mineral fertilizer management is one of the most important agronomic techniques applied in papaya cultivation, which generally extracts large amounts of nutrients from soil, especially nitrogen. This study aimed to assess the phytotechnical and physiological attributes and yield of „Formosa‟ papaya hybrid Caliman 01 as a function of different doses of coated and conventional urea in the region of Bom Jesus - PI, Brazil. The treatments were arranged in a factorial scheme (2 × 4 and distributed in a randomized block design with four replications, corresponding to 2 nitrogen sources (coated urea, 43% of N; and conventional urea, 45% of N and 4 doses nitrogen (350, 440, 530 and 620 g per plant. The N doses used corresponded to 80, 100, 120 and 140% of the nitrogen fertilization. It was used six plants per plot with two row borders, totaling 192 plants cultivated in the field. It was assessed the intercepted photosynthetically active radiation (int.PAR, radiation interception efficiency (PAREff., leaf area index (LAI, plant height, stem diameter and yield. The coated urea promotes a higher growth and yield of „Formosa‟ papaya compared to the conventional urea. The application of 1.0 g of coated N promotes the production of 2.87 g of fruit per hectare while the application of 1.0 g of conventional N produces only 1.89 g of fruit per hectare, showing that the source of polymerized N increases the use efficiency of N applied to soil.

  7. Toward an optimal control strategy for sweet pepper production 2. optimization of the yield pattern and energy efficiency

    NARCIS (Netherlands)

    Henten, van E.J.; Buwalda, F.; Zwart, de H.F.; Gelder, de A.; Hemming, J.

    2006-01-01

    Sweet pepper production is characterized by large fluctuations in fruit yield in time. These fluctuations have a detrimental effect on the operational planning of labor at nursery level as well as on the efficiency of the supply chain. At the same time, the dependence of temperate zone greenhouse

  8. Yields Components and 48-H Rumen Dry Matter Degradation of ...

    African Journals Online (AJOL)

    Two experiments were conducted to study the influence of harvesting date on three sweet potato varieties (TIS-87/0087, TIS-8164 and TIS-2532.OP.1.13). Fodder yields and leaf-to-stem ratio decreased (P < 0.05), while harvest index and 48-h rumen DM degradation increased with maturity from 12 to 20 weeks after ...

  9. Soybean growth and yield under cover crops

    Directory of Open Access Journals (Sweden)

    Priscila de Oliveira

    2013-04-01

    Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

  10. Effect of Salinity Stress and Foliar Application of Methyl Jasmonate on Photosynthetic Rate, Stomatal Conductance, Water Use Efficiency and Yield of German Chamomile

    Directory of Open Access Journals (Sweden)

    fatemeh Salimi

    2014-09-01

    Full Text Available Jasmonate is new plant growth regulator that plays an essential role at increasing plants resistance to the environmental stresses like salinity stress. Hence, in this research the effect of foliar application of methyl jasmonate on some physiological indices and yield of German chamomile under salinity conditions was studied. A factorial experiment was laid out based on randomized complete block design (RCBD with three replications in the greenhouse condition. Foliar application of methyl jasmonate was five levels (MJ1; 0, MJ2; 75, MJ3; 150, MJ4; 225 and MJ5; 300 μM and salinity stress was four levels (S1; 2, S2; 6, S3; 10, S4; 14 dS m-1. The effect of methyl jasmonate, salinity condition treatments and their interaction was significant for traits of photosynthesis rate, stomata conductance, transpiration rate, carboxylation efficiency, intercellular CO2 concentration and yield of flower. The highest values of photosynthetic rate, stomata conductance, transpiration rate, carboxylation efficiency and yield of flower (3.76 g pot-1 and the lowest intercellular CO2 concentration were achieved at MJ×S treatment. Maximum value of photosynthetic water use efficiency was revealed at MJ5×S2 treatment. With decreasing stomata conductance, photosynthetic water use efficiency and intercellular CO2 concentration were increased. In general, it seems that application of methyl jasmonate by lower dose (MJ2 under salinity conditions especially mild salinity stress (S2 can improve physiological indices and yield of chamomile.

  11. Growth, yield, plant quality and nutrition of basil (Ocimum basilicum L. under soilless agricultural systems

    Directory of Open Access Journals (Sweden)

    Subhrajit Saha

    2016-12-01

    Full Text Available Traditional agricultural systems are challenged by globally declining resources resulting from climate change and growing population. Alternative agricultural practices such as aquaponics (includes crop plant and aquatic species and hydroponics (includes crop plant only have the potential to generate high yield per unit area using limited land, water, and no soil. A soilless agricultural study was conducted at the Georgia Southern University, Statesboro, GA, USA from August to November, 2015. The growth, yield, quality, and nutrition of basil (Ocimum basilicum L. cultivar Aroma 2, were compared between aquaponic and hydroponic systems using crayfish (Procambarus spp. as the aquatic species. Non-circulating floating raft systems were designed using 95 L polyethylene tanks. Equal amounts of start-up fertilizer dose were applied to both systems. The objective was to understand how the additional nutritional dynamics associated with crayfish influence the basil crop. Both fresh and dry basil plant weights were collected after harvest, followed by leaf nutrient analysis. Leaf chlorophyll content, water pH, nitrogen and temperature were measured periodically. Aquaponic basil (AqB showed 14%, 56%, and 65% more height, fresh weight, and dry weight, respectively, compared to hydroponic basil (HyB. It is logical to assume that crayfish waste (excreta and unconsumed feed has supplied the additional nutrients to AqB, resulting in greater growth and yield. The chlorophyll content (plant quality or leaf nutrients, however, did not differ between AqB and HyB. Further research is needed to investigate aquaponic crayfish yield, overall nutritional dynamics, cost-benefit ratio, and other plant characteristics under soilless systems.

  12. Yield and nutritional efficiency of corn in response to rates and splits of nitrogen fertilization

    OpenAIRE

    Amado, Telmo Jorge Carneiro; Villalba, Enrique Oswin Hahn; Bortolotto, Rafael Pivotto; Nora, Douglas Dalla; Bragagnolo, Jardes; León, Enrique Asterio Benítez

    2017-01-01

    ABSTRACT Despite its relevance, nitrogen is poorly utilized by the plants when improperly applied. Thus, the objective of this study was to evaluate the yield and nitrogen use efficiency (NUE) in corn in response to doses and split application of nitrogen fertilization. The experimental design was a randomized block design, with three replications. Doses of nitrogen of 0, 30, 60 and 180 kg ha-1 were applied at sowing in order to create different nutritional status of corn plants and to obtain...

  13. Nitrogen management and nitrification inhibitor effects on nitrogen-15 urea: 1. Yield and fertilizer use efficiency

    International Nuclear Information System (INIS)

    Walters, D.T.; Malzer, G.L.

    1990-01-01

    Nitrification inhibitors (NI) are sometimes recommended for use with ammoniacal fertilizers in corn (Zea mays L.) production to improve fertilizer N use efficiency (FUE). The objectives of this experiment were to evaluate the effects of the NI nitrapyrin [2-chloro-6-(trichloromethyl) pyridine] application on yield and FUE of irrigated corn, and to monitor the fate of a single application of 15 N-enriched urea during a multiyear period in both soil and plant. Treatments included a factorial combination of two N rates (90 or 180 kg urea-N ha -1 yr -1 ) applied during a 3-yr period, with or without a NI and with or without incorporation, plus a zero-N control. Twenty-seven nonweighing lysimeters were used to quantify leaching load. Treatment effects on yield and FUE differed each year due to interactions of climate and N-management variables. Nonincorporated urea + NI reduced grain yield when leaching load was low and increased yield at the 90 kg ha -1 N rate when leaching load was low. The NI increased FUE only at the 90 kg ha -1 N rate when leaching load was high. Incorporation of urea + NI reduced plant recovery of fertilizer-derived N (FDN) in the year of application, but resulted in increased uptake of residual FDN in subsequent years. Incorporation of NI with moderate N rates coupled with conservative irrigation management should reduce the risk of yield loss and minimize NO 3 movement to groundwater

  14. The effects of different nitrogen doses on yield, quality and leaf ...

    African Journals Online (AJOL)

    Nitrogen deficiency is a worldwide problem, causing restrictions in productivity of many horticultural produces. Particularly, the issue is compounded when the greenhouse production is employed. Therefore, reliable knowledge on proper application of nitrogen ensures not only satisfactory yield but also balanced vegetative ...

  15. Gas exchanges and water use efficiency in the selection of tomato genotypes tolerant to water stress.

    Science.gov (United States)

    Borba, M E A; Maciel, G M; Fraga Júnior, E F; Machado Júnior, C S; Marquez, G R; Silva, I G; Almeida, R S

    2017-06-20

    Water stress can affect the yield in tomato crops and, despite this, there are few types of research aiming to select tomato genotypes resistant to the water stress using physiological parameters. This experiment aimed to study the variables that are related to the gas exchanges and the efficiency in water use, in the selection of tomato genotypes tolerant to water stress. It was done in a greenhouse, measuring 7 x 21 m, in a randomized complete block design, with four replications (blocks), being five genotypes in the F 2 BC 1 generation, which were previously obtained from an interspecific cross between Solanum pennellii versus S. lycopersicum and three check treatments, two susceptible [UFU-22 (pre-commercial line) and cultivar Santa Clara] and one resistant (S. pennellii). At the beginning of flowering, the plants were submitted to a water stress condition, through irrigation suspension. After that CO 2 assimilation, internal CO 2 , stomatal conductance, transpiration, leaf temperature, instantaneous water use efficiency, intrinsic efficiency of water use, instantaneous carboxylation efficiency, chlorophyll a and b, and the potential leaf water (Ψf) were observed. Almost all variables that were analyzed, except CO 2 assimilation and instantaneous carboxylation efficiency, demonstrated the superiority of the wild accession, S. pennellii, concerning the susceptible check treatments. The high photosynthetic rate and the low stomatal conductance and transpiration, presented by the UFU22/F 2 BC 1 #2 population, allowed a better water use efficiency. Because of that, these physiological characteristics are promising in the selection of tomato genotypes tolerant to water stress.

  16. Physiological characteristics of high yield under cluster planting: photosynthesis and canopy microclimate of cotton

    Directory of Open Access Journals (Sweden)

    Ting-ting Xie

    2016-01-01

    Full Text Available Cotton produces more biomass and economic yield when cluster planting pattern (three plants per hole than in a traditional planting pattern (one plant per hole, even at similar plant densities, indicating that individual plant growth is promoted by cluster planting. The causal factors for this improved growth induced by cluster planting pattern, the light interception, canopy microclimate and photosynthetic rate of cotton were investigated in an arid region of China. The results indicated that the leaf area index and light interception were higher in cluster planting, and significantly different from those in traditional planting during the middle and late growth stages. Cotton canopy humidity at different growth stages was increased but canopy temperatures were reduced by cluster planting. In the later growth stage of cluster planting, the leaf chlorophyll content was higher and the leaf net photosynthetic rate and canopy photosynthetic rate were significantly increased in comparing with traditional planting pattern. We concluded that differences in canopy light interception and photosynthetic rate were the primary factors responsible for increased biomass production and economic yield in cluster planting compared with the traditional planting of cotton.

  17. Canopy reflectance indices and its relationship with yield in common bean plants (Phaseolus vulgaris L.) with phosphorus supply

    International Nuclear Information System (INIS)

    Rodriguez, M.G.; Escalante-Estrada, J.A.; Gonzalez, M.T.R.; Reynolds, M.P.

    2006-01-01

    Common bean plants (Phaseolus vulgaris L.) were grown under three phosphorous levels (0,100 & 200 kg ha-1) and under rain fed conditions with the objective to examine the association between vegetative indices (NDVI, normalized difference vegetation index; and GNDVI, green normalized difference vegetation index) and intercepted radiation, leaf area index, biomass and yield during the growing season. The maximum intercepted radiation, leaf area index (LAI) and biomass were reached during the pod filling stage {80 days after sowing (DAS)}, and the P treatment of 200 kg ha-1 showed the highest values. The high intercepted radiation was derived from an increase in LAI inducing a major biomass accumulation. Near to physiological maturity LAI decreased as a result of leaf abscission. NDVI and GNDVI were higher with P supply than without P at anthesis and pod filling stage (50 - 80 DAS). Near to physiological maturity, NDVI and GNDVI decreased in all the treatments . When the maximum intercepted radiation, LAI, and biomass production were reached during anthesis and pod filling stage, NDVI and GNDVI also had the highest values. The association between the vegetative indices and seed yield during the pod filling stage showed a linear relationship by the P supply. The relationship between GNDVI and seed yield was higher (r2 = 0.77) than the relationship between NDVI and seed yield (r2 = 0.61)

  18. Capability of leaf interdigitation with different inverse planning strategies in Monaco: an investigation of representative tumour sites

    International Nuclear Information System (INIS)

    Duan, Jinghao; Meng, Xiangjuan; Liu, Tonghai; Yin, Yong

    2016-01-01

    The aim of this study was to experimentally assess the dosimetric impact of leaf interdigitation using different inverse treatment strategies for representative tumour sites and to identify the situations in which leaf interdigitation can benefit these tumour sites. Sixty previously treated patients (15 nasopharyngeal carcinoma (NPC), 15 multiple brain metastasis (MBM), 15 cervical cancer and 15 prostate cancer) were re-planned for volumetric modulated arc therapy (VMAT), sliding window IMRT (dMLC) and step-and-shoot IMRT (ssIMRT) with and without leaf interdigitation. Various dosimetric variables, such as PTV coverage, OARs sparing, delivery efficiency and planning time, were evaluated for each plan. In addition, a protocol developed by our group was applied to identify the situations in which leaf interdigitation can achieve benefits in clinical practice. Leaf interdigitation produced few benefits in PTV homogeneity for the MBM VMAT plans and NPC ssIMRT plans. For OARs, sparing was equivalent with and without leaf interdigitation. Leaf interdigitation showed an increase in MUs for dMLC plans and a decrease in MUs for ssIMRT plans. Leaf interdigitation resulted in an increase in segments for dMLC plans and a decrease in segments for NPC and MBM ssIMRT plans. For beam on time, leaf interdigitation showed an increase in MBM dMLC, NPC ssIMRT and prostate ssIMRT plans. In addition, leaf interdigitation saved planning time for VMAT and dMLC plans but increased planning time for ssIMRT plans. Leaf interdigitation does not improve plan quality when performing inverse treatment strategies, regardless of whether the target is simple or complex. However, it influences the delivery efficiency and planning time. Based on these observations, our study suggests that leaf interdigitation should be utilized when performing MBM VMAT plans and NPC ssIMRT plans. The online version of this article (doi:10.1186/s13014-016-0655-1) contains supplementary material, which is available to

  19. Research Advances in High-Yielding Cultivation and Physiology of Super Rice

    Directory of Open Access Journals (Sweden)

    Jing FU

    2012-09-01

    Full Text Available In 1996, China launched a program to breed super rice or super hybrid rice by combining intersubspecific heterosis with ideal plant types. Today, approximately 80 super rice varieties have been released and some of them show high grain yields of 12–21 t/hm2 in field experiments. The main reasons for the high yields of super rice varieties, compared with those of conventional varieties, can be summarized as follows: more spikelets per panicle and larger sink size (number of spikelets per square meter; larger leaf area index, longer duration of green leaf, greater photosynthetic rate, higher lodging resistance, greater dry matter accumulation before the heading stage, greater remobilization of pre-stored carbohydrates from stems and leaves to grains during the grain-filling period; and larger root system and greater root activity. However, there are two main problems in super rice production: poor grain-filling of the later-flowering inferior spikelets (in contrast to earlier-flowering superior spikelets, and low and unstable seed-setting rate. Here, we review recent research advances in the crop physiology of super rice, focusing on biological features, formation of yield components, and population quality. Finally, we suggest further research on crop physiology of super rice.

  20. Impact of abiotic stress on photosynthetic efficiency and leaf temperature in sunflower

    Directory of Open Access Journals (Sweden)

    Antonela Markulj Kulundžić

    2016-11-01

    Full Text Available The aim of this research was to investigate the variability of photosynthetic performance index (PIABS and leaf temperature values measured in V6 development phase on 13 sunflower hybrids, grown in stressful conditions. The pot trial was made up of two treatments, one (T1 with 60% Field Water Capacity (FWC, and the other one (T2 with 80% FWC. Significant differences between T1 and T2 treatments were established for both of these parameters which prove their dependence on the water content in the soil, while the influence of hybrid was evident only in the case of PIABS. Although in T1, as opposed to T2, all sunflower hybrids reacted by increasing leaf temperature, reaction to stress conditions measured with PIABS parameter was not uniform. Some of the hybrids reacted by decreasing PIABS values, while others reacted by increasing their PIABS values. Therefore, it can be concluded that changes in parameters were independent of each other, which was confirmed by correlation analysis. Investigated parameters are suitable for determining the existence of undesirable environmental conditions that cause stress in plants and can be used in breeding of sunflower to withstand abiotic stress conditions, i.e. in selection of stress tolerant hybrids.

  1. Leaf habit and woodiness regulate different leaf economy traits at a given nutrient supply.

    Science.gov (United States)

    Ordoñez, Jenny C; van Bodegom, Peter M; Witte, Jan-Philip M; Bartholomeus, Ruud P; van Dobben, Han F; Aerts, Rien

    2010-11-01

    The large variation in the relationships between environmental factors and plant traits observed in natural communities exemplifies the alternative solutions that plants have developed in response to the same environmental limitations. Qualitative attributes, such as growth form, woodiness, and leaf habit can be used to approximate these alternative solutions. Here, we quantified the extent to which these attributes affect leaf trait values at a given resource supply level, using measured plant traits from 105 different species (254 observations) distributed across 50 sites in mesic to wet plant communities in The Netherlands. For each site, soil total N, soil total P, and water supply estimates were obtained by field measurements and modeling. Effects of growth forms, woodiness, and leaf habit on relations between leaf traits (SLA, specific leaf area; LNC, leaf nitrogen concentration; and LPC, leaf phosphorus concentration) vs. nutrient and water supply were quantified using maximum-likelihood methods and Bonferroni post hoc tests. The qualitative attributes explained 8-23% of the variance within sites in leaf traits vs. soil fertility relationships, and therefore they can potentially be used to make better predictions of global patterns of leaf traits in relation to nutrient supply. However, at a given soil fertility, the strength of the effect of each qualitative attribute was not the same for all leaf traits. These differences may imply a differential regulation of the leaf economy traits at a given nutrient supply, in which SLA and LPC seem to be regulated in accordance to changes in plant size and architecture while LNC seems to be primarily regulated at the leaf level by factors related to leaf longevity.

  2. Physical properties of snacks made from cassava leaf flour

    Directory of Open Access Journals (Sweden)

    Adriana Cristina Ferrari

    2014-02-01

    Full Text Available The food industry is continually growing with new products becoming available every year. Extrusion combines a number of unit operations in one energy efficient rapid continuous process and can be used to produce a wide variety of snacks foods. The objective of this study was to evaluate the effect of extrusion temperature, screw speed, and amount of cassava leaf flour mixed with cassava starch on the physical properties of extruded snacks processed using a single screw extruder. A central composite rotational design, including three factors with 20 treatments, was used in the experimental design. Dependent variables included the expansion index, specific volume, color, water absorption index, and water solubility index. Among the parameters examined, the amount of cassava leaf flour and extrusion temperature showed significant effects on extruded snack characteristics. Mixtures containing 10% of cassava leaf flour extruded at 100°C and 255 rpm shows favorable levels of expansion, color, water absorption index, and water solubility index.

  3. Leaf morphophysiology of a Neotropical mistletoe is shaped by seasonal patterns of host leaf phenology.

    Science.gov (United States)

    Scalon, Marina Corrêa; Rossatto, Davi Rodrigo; Domingos, Fabricius Maia Chaves Bicalho; Franco, Augusto Cesar

    2016-04-01

    Several mistletoe species are able to grow and reproduce on both deciduous and evergreen hosts, suggesting a degree of plasticity in their ability to cope with differences in intrinsic host functions. The aim of this study was to investigate the influence of host phenology on mistletoe water relations and leaf gas exchange. Mistletoe Passovia ovata parasitizing evergreen (Miconia albicans) hosts and P. ovata parasitizing deciduous (Byrsonima verbascifolia) hosts were sampled in a Neotropical savanna. Photosynthetic parameters, diurnal cycles of stomatal conductance, pre-dawn and midday leaf water potential, and stomatal anatomical traits were measured during the peak of the dry and wet seasons, respectively. P. ovata showed distinct water-use strategies that were dependent on host phenology. For P. ovata parasitizing the deciduous host, water use efficiency (WUE; ratio of photosynthetic rate to transpirational water loss) was 2-fold lower in the dry season than in the wet season; in contrast, WUE was maintained at the same level during the wet and dry seasons in P. ovata parasitizing the evergreen host. Generally, mistletoe and host diurnal cycles of stomatal conductance were linked, although there were clear differences in leaf water potential, with mistletoe showing anisohydric behaviour and the host showing isohydric behaviour. Compared to mistletoes attached to evergreen hosts, those parasitizing deciduous hosts had a 1.4-fold lower stomatal density and 1.2-fold wider stomata on both leaf surfaces, suggesting that the latter suffered less intense drought stress. This is the first study to show morphophysiological differences in the same mistletoe species parasitizing hosts of different phenological groups. Our results provide evidence that phenotypical plasticity (anatomical and physiological) might be essential to favour the use of a greater range of hosts.

  4. Studies for reconstruction efficiency and background measurements of {tau} lepton identification in Z {yields} {tau}{tau} decays in data of the ATLAS experiment; Studien zur Messung von Rekonstruktionseffizienz und Untergrund der {tau}-Lepton-Identifikation im Zerfall Z {yields} {tau}{tau} beim ATLAS-Experiment aus Daten

    Energy Technology Data Exchange (ETDEWEB)

    Johnert, Sebastian

    2008-11-15

    In this diploma thesis two methods are presented, by which {tau} leptons shall be studied in the future data of the ATLAS experiment. The first part is formed by the determination of misidentification rates of jets from QCD 2-jet events as {tau} particles. The second part is the development of a method for the determination of the {tau} reconstruction and identification efficiency relatively to the {mu} efficiency. In this connection invariant masses from Z{yields}ll events are determined, the masses from Z{yields}{tau}{tau} events compared with those from Z{yields}ee and Z{yields}{mu}{mu}, {tau} efficiencies averaged over all ranges and in different {eta} ranges calculated as well as a mehtod for the determination of {tau} efficiencies in different transverse-momentum ranges presented. Furthermore an improved estimation of the QCD background is performed and the behaviour of the {tau} efficiency under regardment of the trigger studied. [German] In dieser Diplomarbeit werden zwei Methoden vorgestellt, mit denen {tau}-Leptonen in den zukuenftigen Daten des ATLAS-Experiments untersucht werden sollen. Den ersten Teil bildet die Bestimmung von Missidentifikationsraten von Jets aus QCD-2-Jet-Ereignissen als {tau}-Leptonen. Der zweite Teil ist die Entwicklung einer Methode zur Bestimmung der {tau}-Rekonstruktions und -Identifikationseffizienz relativ zur {mu}-Effizienz. In diesem Zusammenhang werden invariante Massen aus Z {yields} ll-Ereignissen bestimmt, die Massen aus Z {yields} {tau}{tau}-Ereignissen mit denen aus Z {yields} ee und Z {yields} {mu}{mu} verglichen, {tau}-Effizienzen gemittelt ueber alle Bereiche und in verschiedenen {eta}-Bereichen berechnet sowie eine Moeglichkeit zur Bestimmung von {tau}-Effizienzen in unterschiedlichen Transversalimpulsbereichen vorgestellt. Des Weiteren wird eine verbesserte Abschaetzung des QCD-Untergrunds vorgenommen und das Verhalten der {tau}-Effizienz unter Beruecksichtigung des Triggers untersucht. (orig.)

  5. Response of high yielding rice varieties to NaCl salinity in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-05

    Nov 5, 2008 ... the percentage of fertility, stem weight and white grain weight (Kavousi, 1995). ... yield falling in accordance with rising salinity or electrical conduction of ... Due to the effect of salinity on height reduction and its significant effect ..... leaf elongation in maize Is not Mediated by changes in cell wall. Acidification ...

  6. Effect of Irrigation with Wastewater and Foliar Application of Complete Fertilizer on Forage Yield and Yield Components of Foxtail Millet (Setaria italica

    Directory of Open Access Journals (Sweden)

    A Ahmadi Aghtape

    2013-08-01

    Full Text Available In order to study effect of irrigation with wastewater and foliar application of complete fertilizer on forage yield and seed yield and yield components of foxtail millet (Setaria italica. A split plot experiment based on randomized complete block design with three replications was conducted at the Agriculture Institute of Zabol University in year 2009. Treatments included three levels of irrigation: Irrigation with well water at all stages of grows (control, Irrigation with wastewater and tap water alternately, Irrigation with wastewater for all growing stages, as the main plot and sprayed with three levels of complete fertilizer (NATBA-LIB: Non spraying (control, sprayed with 600 and 1200 gram of complete fertilizer in each hectare, as were the subplots. Results showed that irrigation with wastewater and complete fertilizer sprayed had significant effect on all traits except leaf to stem ratio. Furthermore, among the irrigation treatments, irrigation with wastewater in total growing period, and wastewater and tap water alternately lead to significant increase in grain yield, forage yield and yield components. Among the sprayed treatments, sprayed with 1200 gram of complete fertilizer had highest forage yield and grain.

  7. Effect of Addition of Moringa Leaf By-Product (Leaf-Waste) on ...

    African Journals Online (AJOL)

    The effects of incorporation of Moringa leaf fibre (a by-product of leaf processing which contains 24% Crude Fibre by dry weight at 0, 5 and 10 % substitution of wheat flour in cookies was investigated. Three products containing wheat flour: Moringa leaf fibre ratios of 100:0, 95:5, and 90:10 respectively were prepared, and a ...

  8. NAL1 allele from a rice landrace greatly increases yield in modern indica cultivars.

    Science.gov (United States)

    Fujita, Daisuke; Trijatmiko, Kurniawan Rudi; Tagle, Analiza Grubanzo; Sapasap, Maria Veronica; Koide, Yohei; Sasaki, Kazuhiro; Tsakirpaloglou, Nikolaos; Gannaban, Ritchel Bueno; Nishimura, Takeshi; Yanagihara, Seiji; Fukuta, Yoshimichi; Koshiba, Tomokazu; Slamet-Loedin, Inez Hortense; Ishimaru, Tsutomu; Kobayashi, Nobuya

    2013-12-17

    Increasing crop production is essential for securing the future food supply in developing countries in Asia and Africa as economies and populations grow. However, although the Green Revolution led to increased grain production in the 1960s, no major advances have been made in increasing yield potential in rice since then. In this study, we identified a gene, SPIKELET NUMBER (SPIKE), from a tropical japonica rice landrace that enhances the grain productivity of indica cultivars through pleiotropic effects on plant architecture. Map-based cloning revealed that SPIKE was identical to NARROW LEAF1 (NAL1), which has been reported to control vein pattern in leaf. Phenotypic analyses of a near-isogenic line of a popular indica cultivar, IR64, and overexpressor lines revealed increases in spikelet number, leaf size, root system, and the number of vascular bundles, indicating the enhancement of source size and translocation capacity as well as sink size. The near-isogenic line achieved 13-36% yield increase without any negative effect on grain appearance. Expression analysis revealed that the gene was expressed in all cell types: panicles, leaves, roots, and culms supporting the pleiotropic effects on plant architecture. Furthermore, SPIKE increased grain yield by 18% in the recently released indica cultivar IRRI146, and increased spikelet number in the genetic background of other popular indica cultivars. The use of SPIKE in rice breeding could contribute to food security in indica-growing regions such as South and Southeast Asia.

  9. Characteristic, inheritance and breeding application of rice mutants with greenable albino leaf

    International Nuclear Information System (INIS)

    Fang Xiantao; Ma Hongli; Zhao Fuyuan; Zhang Qingqi; Zhang Shubiao

    2009-01-01

    Inheritance and main agronomic traits of photo-thermo-sensitive genic male sterile line with green-revertible albino leaf were investigated. The results indicated that the mutants might be divided into three types: albino regreening type (W2, W3, W4 and W10), albino to kelly type (W9) and abino-regreening-albino-regreening type (W1 and W7). Genetic study indicated that green-revertible albino leaf color trait of the mutants as controlled by a single recessive gene. These mutants had similar agronomic traits and fertility characteristics to the corresponding male sterile line 'Peiai 64S'. The hybrids of these mutants had similar characteristics with original-hybrids in plant type, developing of tillers and plant height. The yield components of the mutant hybrids were different depending on different mutants. The yield potential of hybrids of W1, W2 and W3 were similar to the original-hybrid. The results also indicated that W1, W2 and W3 had breeding application value. (authors)

  10. Effects of shading on dry matter partitioning and yield of field-grown sunflower

    International Nuclear Information System (INIS)

    Villalobos, F.J.; Soriano, A.; Fereres, E.

    1992-01-01

    Crop simulation models require quantitative descriptions of the effects of irradiance on dry matter partition and yield. The objective of this work was to quantify the effects of reduced radiation intensity during different phenological stages on the growth, dry matter partitioning and grain numbers of sunflower (Helianthus annuus, L.). A field experiment was carried out in 1990 with 50 per cent shading treatments. The earliest treatment began at crop emergence while the latest ended at first anthesis. Shading had little effect on plant leaf area growth but reduced biomass and yield. The dry matter: radiation quotient and specific leaf area increased with shading. Grain number per head was decreased by shading, with the greatest effect occurring when shading was applied prior to anthesis. All shading treatments increased dry matter partitioning to stems, decreased assimilate partitioning to the heads and had no effect on the partitioning to leaves. (author)

  11. Evaluation of water-use efficiency in foxtail millet (Setaria italica) using visible-near infrared and thermal spectral sensing techniques.

    Science.gov (United States)

    Wang, Meng; Ellsworth, Patrick Z; Zhou, Jianfeng; Cousins, Asaph B; Sankaran, Sindhuja

    2016-05-15

    Water limitations decrease stomatal conductance (g(s)) and, in turn, photosynthetic rate (A(net)), resulting in decreased crop productivity. The current techniques for evaluating these physiological responses are limited to leaf-level measures acquired by measuring leaf-level gas exchange. In this regard, proximal sensing techniques can be a useful tool in studying plant biology as they can be used to acquire plant-level measures in a high-throughput manner. However, to confidently utilize the proximal sensing technique for high-throughput physiological monitoring, it is important to assess the relationship between plant physiological parameters and the sensor data. Therefore, in this study, the application of rapid sensing techniques based on thermal imaging and visual-near infrared spectroscopy for assessing water-use efficiency (WUE) in foxtail millet (Setaria italica (L.) P. Beauv) was evaluated. The visible-near infrared spectral reflectance (350-2500 nm) and thermal (7.5-14 µm) data were collected at regular intervals from well-watered and drought-stressed plants in combination with other leaf physiological parameters (transpiration rate-E, A(net), g(s), leaf carbon isotopic signature-δ(13)C(leaf), WUE). Partial least squares regression (PLSR) analysis was used to predict leaf physiological measures based on the spectral data. The PLSR modeling on the hyperspectral data yielded accurate and precise estimates of leaf E, gs, δ(13)C(leaf), and WUE with coefficient of determination in a range of 0.85-0.91. Additionally, significant differences in average leaf temperatures (~1°C) measured with a thermal camera were observed between well-watered plants and drought-stressed plants. In summary, the visible-near infrared reflectance data, and thermal images can be used as a potential rapid technique for evaluating plant physiological responses such as WUE. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Effect of water stress on growth, yield and water use efficiency of berseem (Trifolium alexandrium in Tadla

    Directory of Open Access Journals (Sweden)

    B. Bouazzama

    2018-01-01

    Full Text Available The study of crop response to water deficit is important in areas where water resources are limited. This study was carried out over the period 2008-2011 in order to study the effect of water deficit on the productivity of berseem in the Tadla region. Four water regimes (100%, 80%, 60% and 40% ETc were compared under both flood and drip irrigation techniques. Observations were made on the soil, biomass at each cut and root system. The results showed that the average annual maximum yield obtained was 16.2 t/ha. Reductions in yields by applying 60% of water inputs are 40% and 42% in 2009/10 and 2010/11, respectively. The contribution of cycles without irrigation to annual biomass yield varies from 35% under 100% ETc to 52% under 40% ETc. Water use efficiency of berseem over the over the entire crop period is 3.37 kg/m3. The maximum average yield obtained under drip irrigation was 15.7 t/ha. It was obtained with a water supply of 411 mm which allowed a saving of 57% of water supply versus flood irrigation technique.

  13. Differences between winter oilseed rape (Brassica napus L.) cultivars in nitrogen starvation-induced leaf senescence are governed by leaf-inherent rather than root-derived signals

    Czech Academy of Sciences Publication Activity Database

    Koeslin-Findeklee, F.; Becker, M. A.; van der Graaff, E.; Roitsch, Thomas; Horst, W. J.

    2015-01-01

    Roč. 66, č. 13 (2015), s. 3669-3681 ISSN 0022-0957 Institutional support: RVO:67179843 Keywords : Brassica napus * cytokinins * genotypic differences * leaf senescence * nitrogen efficiency * nitrogen starvation * reciprocal grafting * stay-green Subject RIV: EH - Ecology, Behaviour Impact factor: 5.677, year: 2015

  14. Characterization and pathogenicity of Fusarium species associated with leaf spot of mango (Mangifera indica L.).

    Science.gov (United States)

    Omar, Nurul Husna; Mohd, Masratulhawa; Mohamed Nor, Nik Mohd Izham; Zakaria, Latiffah

    2018-01-01

    Leaf spot diseases are mainly caused by fungi including Fusarium. In the present study several species of Fusarium were isolated from the leaf spot lesion of mango (Mangifera indica L.) Based on morphological characteristics, TEF-1α sequences and phylogenetic analysis, five species were identified as F. proliferatum, F. semitectum, F. mangiferae, F. solani and F. chlamydosporum. Pathogenicity test indicated that representative isolates of F. proliferatum, F. semitectum and F. chlamydosporum were pathogenic on mango leaves causing leaf spot with low to moderate virulence. Nevertheless, abundance of spots on the leaf can disrupt photosynthesis which in turn reduced growth, and lead to susceptibility to infection by opportunistic pathogens due to weakening of the plant. Fusarium solani and F. mangiferae were non-pathogenic and it is possible that both species are saprophyte which associated with nutrient availability on the surface of the leaf through decaying leave tissues. The occurrence of Fusarium spp. on the leaf spot lesion and the effect from the disease needs to be considered when developing disease management method of mango cultivation as numerous spot on the leaves could effect the photosynthesis process and finally giving low yield and less quality of mango. Copyright © 2017. Published by Elsevier Ltd.

  15. Global variability in leaf respiration in relation to climate and leaf traits

    Science.gov (United States)

    Atkin, Owen K.

    2015-04-01

    Leaf respiration plays a vital role in regulating ecosystem functioning and the Earth's climate. Because of this, it is imperative that that Earth-system, climate and ecosystem-level models be able to accurately predict variations in rates of leaf respiration. In the field of photosynthesis research, the F/vC/B model has enabled modellers to accurately predict variations in photosynthesis through time and space. By contrast, we lack an equivalent biochemical model to predict variations in leaf respiration. Consequently, we need to rely on phenomenological approaches to model variations in respiration across the Earth's surface. Such approaches require that we develop a thorough understanding of how rates of respiration vary among species and whether global environmental gradients play a role in determining variations in leaf respiration. Dealing with these issues requires that data sets be assembled on rates of leaf respiration in biomes across the Earth's surface. In this talk, I will use a newly-assembled global database on leaf respiration and associated traits (including photosynthesis) to highlight variation in leaf respiration (and the balance between respiration and photosynthesis) across global gradients in growth temperature and aridity.

  16. Comparing Relationships among Yield and Its Related Traits in Mycorrhizal and Nonmycorrhizal Inoculated Wheat Cultivars under Different Water Regimes Using Multivariate Statistics

    Directory of Open Access Journals (Sweden)

    Armin Saed-Moucheshi

    2013-01-01

    Full Text Available Multivariate statistical techniques were used to compare the relationship between yield and its related traits under noninoculated and inoculated cultivars with mycorrhizal fungus (Glomus intraradices; each one consisted of three wheat cultivars and four water regimes. Results showed that, under inoculation conditions, spike weight per plant and total chlorophyll content of the flag leaf were the most important variables contributing to wheat grain yield variation, while, under noninoculated condition, in addition to two mentioned traits, grain weight per spike and leaf area were also important variables accounting for wheat grain yield variation. Therefore, spike weight per plant and chlorophyll content of flag leaf can be used as selection criteria in breeding programs for both inoculated and noninoculated wheat cultivars under different water regimes, and also grain weight per spike and leaf area can be considered for noninoculated condition. Furthermore, inoculation of wheat cultivars showed higher value in the most measured traits, and the results indicated that inoculation treatment could change the relationship among morphological traits of wheat cultivars under drought stress. Also, it seems that the results of stepwise regression as a selecting method together with principal component and factor analysis are stronger methods to be applied in breeding programs for screening important traits.

  17. Various rates of k and Na influence growth, seed cotton yield and ionic ratio of two cotton varieties in soil culture

    International Nuclear Information System (INIS)

    Ali, L.; Maqsood, M.A.; Ashraf, M.

    2009-01-01

    Cotton is generally grown on alkaline calcareous soils in arid and semi-arid areas of the country. Sodium can interact with other earth cations like K, Ca and Mg. Therefore, a pot study was conducted to investigate the growth, yield and ionic response of two cotton varieties. Four levels of K and Na were developed after considering indigenous K, Na status in soil. The treatments of K+Na in mg/kg were adjusted as, 105+37.5, 135+30 135+37.5 and 105+30 (control). Control treatment represented indigenous K, Na status of soil. The experiment continued until maturity. Application of K and Na increased seed cotton yield and boll weight significantly (p<0.01). Both varieties varied non-significantly with respect to K:Na ratio in leaf. The beneficial effects of Na with K application over control on seed cotton yield and boll weight were greater in NIBGE-2 than in MNH-786. Increase in seed cotton yield was attributed to maximum boll weight of both varieties. Significant negative correlation (r= -0.89, - 0.76, n= 4) was found between K:Na ratio and K use efficiency in shoot of NIBGE-2 and MNH-786, respectively. (author)

  18. Evaluation of leaf energy dissipation by the Photochemical Reflectance

    Science.gov (United States)

    Raddi, S.; Magnani, F.

    Starting from the early paper by Heber (1969), several studies have demonstrated a subtle shift in leaf spectroscopic characteristics (both absorbance and reflectance) in response to rapid changes in environmental conditions. More recent work, briefly reviewed here, has also demonstrated the existence of two components in the maked peak centered at 505-540 nm: an irreversible component, attributed to the interconversion of leaf xanthophylls, and a reversible component at slightly longer wavelengths, resulting from conformational changes induced by the buildup of a pH gradient across the thylakoid membrane associated with photosynthetic electron transport. Both processes (xanthophyll de-epoxidation and conformational changes) are known to contribute to the dissipation of excess energy in Photosystem II (PSII). Leaf spectroscopy could therefore provide a powerful non-invasive tool for the determination of leaf photosynthetic processes. This led to the development of the normalized spectral index PRI (Photochemical Reflectance Index; Gamon, Penuelas &Field 1992; Gamon, Serrano &Surfus 1997), which relates the functional signal at 531 nm to a reference signal at 570 nm. The index has been found to track diurnal changes in xanthophyll de-epoxidation state, radiation use efficiency and fluorescence in response to light, both at the leaf and more recently at the canopy level. A common relationship has also beenreported across species and functional types, although such a generality has not always been confirmed. Recent reports (Stylinski et al. 2000) have also hinted of a possible link between PRI and leaf photosynthetic potential, possibly through the correlation between xanthophyll content and electron transport machinery in the chloroplast. Such a link, if confirmed, could prove very useful for the remote sensing and modelling ofvegetation. Some of these open questions were addressed in the present study. The correlation between leaf function and reflectance was

  19. Use of Carbon -14 and Phosphorus -32 to study phosphorus acquisition efficiency in crop plants

    International Nuclear Information System (INIS)

    Pandey, Renu; Vengavasi, Krishnapriya

    2017-01-01

    Low bioavailability of phosphorus (P) in soils is one of the major limiting factors to crop production throughout the world. P nutrition improves yield, with significant influences on the above- (leaf area, photosynthesis, dry matter accumulation, leaf P content) and below-ground (root morphology, exudation, symbiosis) processes (Pandey et al., 2015). Plants, however, are known to possess potential adaptive mechanisms at morphological, physiological, biochemical, and molecular levels to overcome P deficiency. Such adaptive mechanisms mainly include an increase in total root length and root hair growth (Pandey et al., unpublished), enhancement of organic acids (Vengavasi and Pandey, 2016a, b), acid phosphatase (Pandey, 2006) and ribonuclease (RNase) secretion into the rhizosphere (Hocking, 2001), increase in expression of proteins such as phosphatase, inorganic phosphate (Pi) transporter, RNase and phosphoenolpyruvate carboxylase (PEPcase) in plant tissues (Ragothama, 1999). Of all the above, rhizosphere acidification provides maximum exploration of soil volume around the rooting zone leading to conversion of non-available nutrients into available forms thus, resulting in enhanced uptake efficiency

  20. Effects of dripper discharge and irrigation frequency on growth and yield of maize in loess plateau of northwest china

    International Nuclear Information System (INIS)

    Xiukang, W.; Zhanbin, L.; Yingying, X.

    2014-01-01

    A field experiment was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, in northwestern China from 2010 to 2011 with four treatments and six replicates in a randomized complete block design to determine appropriate dripper discharge and irrigation frequency for maize (Zea mays, L.) irrigated by drip irrigated system. Dripper discharge was applied to maize 1L/h of dripper discharge, 2 days irrigation frequency and 100% of evaporation from a class a pan (T1), 2, 3 and 4 L/h corresponding to 4, 6 and 8 days irrigation frequency, and deficit irrigation water levels was 90%, 80% and 70% of evaporation (T2, T3 and T4), respectively. The results indicated that longest root, root activity, plant height, leaf area, biomass and grain yields values were highest in T1 in both years. The highest grain yield was obtained of 8.78 and 8.84 t ha-1 under T1 in both years, and the minimum yield was obtained with 8.15 and 7.78 t ha-1 under T4 in 2010 and 2011, respectively. The maximum irrigation water use efficiency (IWUE) was 3.247 and 3.283 kg m-3 in both years under T4. Despite the reduction of growth and grain yield in T3, the dripper discharge was 3L/h, 6 days irrigation frequency and 80% of evaporation was still high and acceptable for maize production and irrigation water use efficiency in Loess Plateau of Northwest China. (author)