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Sample records for chlorophylls content net

  1. Effect of gamma radiation on chlorophylls contents, net photosynthesis and respiration of chlorella pyrenoidosa

    International Nuclear Information System (INIS)

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy on chlorophylls content, net photosynthesis and respiration of chlorella pyrenoidosa has been studied. A decrease in chlorophylls levels is produced after irradiation at 500, 1000 and 5000 Gy, being, at first 'b' chlorophyll affected to a greater extent than 'a' chlorophyll. Net photosynthesis and respiration decline throughout the time of the observations after irradiation, this depressing effect being much more remarkable for the first one. Net photosynthesis inhibition levels of about 30% have got only five hours post irradiation at a dose of 5000 Gy. (author)

  2. Effect of gamma radiation on chlorophylls content, net photosynthesis and respiration of Chlorella pyrenoidosa

    International Nuclear Information System (INIS)

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy on chlorophylls content, net photosynthesis and respiration of Chlorella pyrenoidosa has been studied. A decrease in chlorophylls levels is produced after irradiation at 500, 1000 and 5000 Gy, being, at first b chlorophyll affected to a greater extent than a chlorophyll. Net photosynthesis and respiration decline throughout the time of the observation after irradiation, this depressing effect being much more remarkable for the first one. Met photosynthesis inhibition levels of about 30% are got only five hours post irradiation at a dose of 5000 Gy. Radio estimation by low doses, although obtained in some cases for tho 10 Gy dose, has not been statistically confirmed. (Author) 23 refs

  3. Effect of gamma radiation on chlorophylls content, net photosynthesis and respiration of Chlorella pyrenoidosa; Efecto de la radiacion gamma sobre la fotosintesis neta y la respiracion de Chlorella pyrenoidosa

    Energy Technology Data Exchange (ETDEWEB)

    Martin, C.; Fernandez, J.

    1983-07-01

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy on chlorophylls content, net photosynthesis and respiration of Chlorella pyrenoidosa has been studied. A decrease in chlorophylls levels is produced after irradiation at 500, 1000 and 5000 Gy, being, at first b chlorophyll affected to a greater extent than a chlorophyll. Net photosynthesis and respiration decline throughout the time of the observation after irradiation, this depressing effect being much more remarkable for the first one. Met photosynthesis inhibition levels of about 30% are got only five hours post irradiation at a dose of 5000 Gy. Radio estimation by low doses, although obtained in some cases for tho 10 Gy dose, has not been statistically confirmed. (Author) 23 refs.

  4. Chlorophyll a + b content and chlorophyll fluorescence in avocado

    Science.gov (United States)

    One Tonnage (T) and one Simmonds (S) avocado tree and four TxS crosses were evaluated for differences in chlorophyll content and maximal quantum yield of photosystem II in sun and shade-type leaves. Total chlorophyll content by area (Chl a+bar) ranged from 981 mg m-2 in TxS240 to 4339 mg m-2 in Simm...

  5. QTL Mapping of Chlorophyll Contents in Rice

    Institute of Scientific and Technical Information of China (English)

    SHEN Bo; ZHUANG Jie-yun; ZHANG Ke-qin; DAI Wei-min; LU Ye; FU Li-qing; DING Jia-ming; ZHENG Kang-le

    2007-01-01

    The objectives of this study were to investigate the genetic factors controlling the chlorophyll content of rice leaf using QTL analysis. A linkage map consisting of 207 DNA markers was constructed by using 247 recombinant inbred lines (RILs) derived from an indica-indica rice cross of Zhenshan97B×Milyang 46. In 2002 and 2003, the contents of chlorophyll a and b of the parents and the 247 RILs were measured on the top first leaf, top second leaf, and top third leaf, respectively. The software QTLMapper 1.6 was used to detect quantitative trait loci (QTLs), additive by environment (AE) interactions, and epistatic by environment (AAE) interactions. A total of eight QTLs in four intervals were detected to have significant additive effects on chlorophyll a and b contents at different leaf positions, with 1.96-9.77% of phenotypic variation explained by a single QTL, and two QTLs with significant AE interactions were detected. Epistasis analysis detected nine significant additive-by-additive interactions on chlorophyll a and b contents, and one pair of QTLs with significant AAE interactions was detected. On comparison with QTLs for yield traits detected in the same population, it was found in many cases that the QTLs for chlorophyll a and b contents and those for yield traits were located in the same chromosome intervals.

  6. [Estimation of canopy chlorophyll content using hyperspectral data].

    Science.gov (United States)

    Dong, Jing-Jing; Wang, Li; Niu, Zheng

    2009-11-01

    Many researches have developed models to estimate chlorophyl content at leaf and canopy level, but they were species-specific. The objective of the present paper was to develop a new model. First, canopy reflectance was simulated for different species and different canopy architecture using radiative transfer models. Based on the simulated canopy reflectance, the relationship between canopy reflectance and canopy chlorophyll content was studied, and then a chlorophyll estimation model was built using the method of spectral index. The coefficient of determination (R2) between spectral index based model and canopy chlorophyll content reached 0.75 for simulated data. To investigate the applicability of this chlorophyll model, the authors chose a field sample area in Gansu Province to carry out the measurement of leaf chlorophyll content, canopy reflectance and other parameters. Besides, the authors also ordered the synchronous Hyperion data, a hyperspectral image with a spatial resolution of 30 m. Canopy reflectance from field measurment and reflectance from Hyperion image were respectively used as the input parameter for the chlorophyll estimation model. Both of them got good results, which indicated that the model could be used for accurate canopy chlorophyll estimation using canopy reflectance. However, while using spaceborne hyperspectral data to estimate canopy chlorophyll content, good atmospheric correction is required. PMID:20101973

  7. Effects of biocides on chlorophyll contents of detached basil leaves

    Directory of Open Access Journals (Sweden)

    Titima Arunrangsi

    2013-06-01

    Full Text Available Herbicides and insecticides have been widely and intensively used in agricultural areas worldwide to enhance crop yield. However, many biocides cause serious environmental problems. In addition, the biocides may also have some effects on the treated agricultural crops. To study effects of biocides on chlorophyll content in detached basil leaves, 2,4-D dimethylamine salt (2,4 D-Amine, paraquat, carbosulfan, and azadirachtin, were chosen as representatives of biocide. After applying the chemicals to detached basil leaves overnight in darkness, chlorophyll contents were determined. Only treatment with 2,4 D-Amine resulted in reduction of chlorophyll contents significantly compared to treatment with deionized (DI water. In the case of paraquat and carbosulfan, chlorophyll contents were not significantly changed, while slightly higher chlorophyll contents, compared to DI water, after the treatment with azadirachtin, were observed. The results indicated that 2,4 D-Amine shows an ability to accelerate chlorophyll degradation, but azadirachtin helps to retard chlorophyll degradation, when each biocide is used at the concentration recommended by the manufacturer.

  8. Surface disturbance of cryptobiotic soil crusts: nitrogenase activity, chlorophyll content, and chlorophyll degradation

    Science.gov (United States)

    Belnap, Jayne; Harper, Kimball T.; Warren, Steven D.

    1994-01-01

    Cryptobiotic soil crusts are an important component of semiarid and arid ecosystems. An important role of these crusts is the contribution of fixed nitrogen to cold‐desert ecosystems. This study examines the residual effects of various intensities and combinations of different surface disturbances (raking, scalping, and tracked vehicles) on nitrogenase activity, chlorophyll content, and chlorophyll degradation in these soil crusts. Nine months after disturbance chlorophyll content of disturbed soils was not statistically different from undisturbed controls, except in the scalped treatments, indicating recovery of this characteristic is fairly quick unless surface material is removed. Differences in chlorophyll degradation among treatments were not statistically significant. However, nitrogenase activity in all treatments showed tremendous reductions, ranging from 77–97%, when compared to the control, indicating this characteristic is slow to recover. Consequently, assessment of crustal recovery from disturbance must include not only visual and biomass characteristics but other physiological measurements as well. Areas dominated by these crusts should be managed conservatively until the implications of crustal disturbance is better understood.

  9. QTLs for Rice Leaf Chlorophyll Content Under Low N Stress

    Institute of Scientific and Technical Information of China (English)

    FANG Ping; YU Xiao-Min; ZHU Ri-Qing; WU Ping

    2004-01-01

    Quantitative trait loci (QTLs) for chlorophyll content of a rice leaf were mapped on to the molecular marker linkage nutrient solution and soil culture experiments to detect rice nitrogen nutrition status under low N stress. A chlorophyll meter was used to measure the soil plant analysis development (SPAD) value of the topmost fully expanded leaf as the index of chlorophyll content that expressed nitrogen status in rice plants. Totally 3 QTLs for SPAD values, two on chromosome 3 located at interval RG179-CDO337 and RG348-RZ329, respectively, and one on chromosome 10 at interval RZ500-RG134, were detected under stressed conditions of low N in the soil and/or nutrient solution culture experiments.One QTL located at interval RG179-CDO337 on chromosome 3 associated with a relative change in SPAD value from a high N level to a low N level in the soil culture experiment was also detected. Based on the different responses to low N stress between the two parents, it was supposed that the QTLs identified in this study associated with nitrogen efficiency in rice at low N levels might be useful in applying marker technology to rice breeding programs.

  10. [Vegetation index estimation by chlorophyll content of grassland based on spectral analysis].

    Science.gov (United States)

    Xiao, Han; Chen, Xiu-Wan; Yang, Zhen-Yu; Li, Huai-Yu; Zhu, Han

    2014-11-01

    Comparing the methods of existing remote sensing research on the estimation of chlorophyll content, the present paper confirms that the vegetation index is one of the most practical and popular research methods. In recent years, the increasingly serious problem of grassland degradation. This paper, firstly, analyzes the measured reflectance spectral curve and its first derivative curve in the grasslands of Songpan, Sichuan and Gongger, Inner Mongolia, conducts correlation analysis between these two spectral curves and chlorophyll content, and finds out the regulation between REP (red edge position) and grassland chlorophyll content, that is, the higher the chlorophyll content is, the higher the REIP (red-edge inflection point) value would be. Then, this paper constructs GCI (grassland chlorophyll index) and selects the most suitable band for retrieval. Finally, this paper calculates the GCI by the use of satellite hyperspectral image, conducts the verification and accuracy analysis of the calculation results compared with chlorophyll content data collected from field of twice experiments. The result shows that for grassland chlorophyll content, GCI has stronger sensitivity than other indices of chlorophyll, and has higher estimation accuracy. GCI is the first proposed to estimate the grassland chlorophyll content, and has wide application potential for the remote sensing retrieval of grassland chlorophyll content. In addition, the grassland chlorophyll content estimation method based on remote sensing retrieval in this paper provides new research ideas for other vegetation biochemical parameters' estimation, vegetation growth status' evaluation and grassland ecological environment change's monitoring. PMID:25752061

  11. 27 CFR 5.38 - Net contents.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Net contents. 5.38 Section 5.38 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF DISTILLED SPIRITS Labeling Requirements for...

  12. 27 CFR 4.37 - Net contents.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Net contents. 4.37 Section 4.37 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Labeling Requirements for Wine § 4.37...

  13. Estimate of Leaf Chlorophyll and Nitrogen Content in Asian Pear (Pyrus serotina Rehd. by CCM-200

    Directory of Open Access Journals (Sweden)

    Mostafa GHASEMI

    2011-03-01

    Full Text Available In many cases evaluation of chlorophyll and nitrogen content in plants need to destructive methods, more time and organic solvents. Application of chlorophyll meters save time and resources. The aim of this study was estimating of chlorophyll and nitrogen content in Asian pear leaves using non-destructive method and rapid quantification of chlorophyll by chlorophyll content meter (CCM-200. This study was conducted on 8 years old Asian pear trees during June 2008 in Tehran, Iran. To develop our regression model, the chlorophyll meter data were correlated with extracted chlorophyll and nitrogen content data obtained from DMSO and Kejeldal methods, respectively. The results showed that, there was positive and linear correlation between CCM-200 data and chlorophyll a (R�=0.7183, chlorophyll b (R�=0.8523, total chlorophyll (R�=0.90, and total nitrogen content (R�=0.76 in Asian pear leaves. Thus, it can be concluded that, CCM-200 can be used in order to predict both chlorophyll and nitrogen content in Asian pear leaves.

  14. Fluorescent indices of oak and wheat leaves in dependence on chlorophyll content

    Science.gov (United States)

    Kalmatskaya, Olesya Ð. ń.; Karavaev, Vladimir A.; Gunar, Lyudmila E.

    2016-04-01

    Fluorescence spectra and fluorescence induction curves of the leaves of two plant species in dependence on chlorophyll content were studied. Red oak (Quercus rubra L.) leaves upon the autumn chlorophyll degradation, as well as wheat leaves (Triticum aestivum L.) at various stages of ontogenesis showed linear dependence between the ratio ω = F740 / F685 (the ratio of the maximum values of fluorescence at respective wavelengths) and chlorophyll content. In both cases, parameter Fv / Fm (the relative value of the variable fluorescence) remained almost unchanged up to significant reduction of chlorophyll content, indicating on maintaining the high photochemical activity of photosystem 2.

  15. Effect of automobile pollution on chlorophyll content of roadside urban trees

    Directory of Open Access Journals (Sweden)

    M. Iqbal

    2015-09-01

    Full Text Available The effect of automobile pollution was determined on chlorophyll content of four different tree species viz. Azadirachta indica L., Conocarpus erectus L., Guiacum officinale L.and Eucalyptus sp. growing along the roads of the city.  Significant changes in the level of chlorophyll “a”, chlorophyll “b” and total chlorophyll “a+b” were found in the leaves of four tree species (A. indica, C. erectus, G.officinale and Eucalyptus sp. collected from polluted sites (Airport, Malir Halt, Quaidabad as compared to control site (Karachi University Campus. Lowest concentration of chlorophyll “a”, chlorophyll “b” and chlorophyll “a+b” was recorded in the leaf samples of all tree species collected from Quaidabad site when compared with the leaf samples collected from control site. The highest levels of chlorophyll pigment were recorded in all tree species leave samples collected from Karachi University Campus.  Similarly, better levels of chlorophyll “a”, chlorophyll “b” and total chlorophyll “a+b” was observed in all tree species growing at Airport site as compared to plants growing at Malir Halt and Quaidabad sites.  This study clearly indicated that the vehicular activities induced air pollution problem and affected on the level of chlorophyll pigments in trees which were exposed to road side pollution.

  16. TOXICITY OF INDUSTRIAL EFFLUENT ON TOTAL CHLOROPHYLL CONTENT OF CERTAIN AQUATIC MACROPHYTES

    Directory of Open Access Journals (Sweden)

    Singh Priti

    2012-04-01

    Full Text Available To assess the toxicity of industrial effluents on certain macrophytes, the total chlorophyll content of free floating, submerged and emergent macrophytes were estimated in concentrations of industrial effluents at varying exposure duration. The result revealed reduction in total chlorophyll content of exposed macrophytes at higher concentrations of industrial effluents on prolonged duration.

  17. TOXICITY OF INDUSTRIAL EFFLUENT ON TOTAL CHLOROPHYLL CONTENT OF CERTAIN AQUATIC MACROPHYTES

    OpenAIRE

    Singh Priti; Vishen Ashish; Wadhwani R; Pandey Y.N

    2012-01-01

    To assess the toxicity of industrial effluents on certain macrophytes, the total chlorophyll content of free floating, submerged and emergent macrophytes were estimated in concentrations of industrial effluents at varying exposure duration. The result revealed reduction in total chlorophyll content of exposed macrophytes at higher concentrations of industrial effluents on prolonged duration.

  18. Genetic dissection of chlorophyll content at different growth stages in common wheat

    Indian Academy of Sciences (India)

    Kunpu Zhang; Zhijun Fang; Yan Liang; Jichun Tian

    2009-08-01

    Quantitative trait loci (QTLs) for chlorophyll content were studied using a doubled haploid (DH) population with 168 progeny lines, derived from a cross between two elite Chinese wheat cultivars Huapei 3 × Yumai 57. Chlorophyll content was evaluated at the maximum tillering stage (MS), the heading stage (HS), and the grain filling stage (GS), at three different environments in 2005 and 2006 cropping seasons. QTL analyses were performed using a mixed linear model approach. A total of 17 additive QTLs and nine pairs of epistatic QTLs were detected. Ten of 17 additive QTLs for chlorophyll content were persistently expressed at more than two growth stages, which suggest developmentally regulated loci controlling genetics for chlorophyll content in different growth stages in wheat. One novel major QTL for chlorophyll content was closely linked with the PCR marker Xwmc215 and was persistently expressed at three growth stages.

  19. Influence of frequent magnetic field on chlorophyll content in leaves of sugar beet plants

    International Nuclear Information System (INIS)

    Chlorophyll content in plant leaves is correlated with the yield and nitrogen content in plants. Non-destructive investigations of chlorophyll content in leaves of 3 varieties of sugar beet grown from seeds revealed that a low frequent magnetic field, acting independently or in combination with other methods of seed improvement, increased chlorophyll content in leaves of the investigated plants. The treatment with the magnetic field increased nitrogen content in the examined plants. The effect was not connected with environmental conditions during vegetation seasons. (author)

  20. Rapid assessment of water pollution by airborne measurement of chlorophyll content.

    Science.gov (United States)

    Arvesen, J. C.; Weaver, E. C.; Millard, J. P.

    1971-01-01

    Present techniques of airborne chlorophyll measurement are discussed as an approach to water pollution assessment. The differential radiometer, the chlorophyll correlation radiometer, and an infrared radiometer for water temperature measurements are described as the key components of the equipment. Also covered are flight missions carried out to evaluate the capability of the chlorophyll correlation radiometer in measuring the chlorophyll content in water bodies with widely different levels of nutrients, such as fresh-water lakes of high and low eutrophic levels, marine waters of high and low productivity, and an estuary with a high sediment content. The feasibility and usefulness of these techniques are indicated.

  1. Chlorophyll content, productivities and biomass allocations of seagrasses in Talim Bay, Lian, Batangas, Philippines

    Directory of Open Access Journals (Sweden)

    Michael A. Clores

    2013-09-01

    Full Text Available This study determined the chlorophyll content, productivities and biomass allocations of three abundant species of seagrasses in Talim Bay, Lian, Batangas. Philippines: Enhalus acoroides, Cymodocea rotundata, and Thalassia hemprichii. Four seagrass meadows in the bay were selected based on their terrestrial sources of nutrient loads. Results reveal that seagrasses at South Matuod (a site which receives nutrient load drained mostly from corn- and cane-fields, yields the highest GPP (Gross Primary Productivity, but R (Respiration is higher than GPP, and therefore NPP (Net Primary Productivity was negative. The same pattern of productivity values were observed in the other sites implying that seagrasses were not making enough oxygen for their life processes at the time of the study (October to November 2010. Although the NPP of seagrasses was negative in Talim Point, (a site which does not receive nutrient load from terrestrial area serving as the control site, they had the highest chlorophyll a and b content with the other sites. R in this site is the lowest despite its low GPP, suggesting a more efficient primary production. Seagrasses in Kayreyna (which receives nutrient load from primarily from sewerage as well as farmland, i.e., near one creek that drains houses had the highest total average Wet weight (WW, Dry Weight (DW and Ash-Free Dry Weight (AFDW while those seagrasses collected in South Matuod had the lowest biomass. The low biomass of seagrasses in Matuod could be related to their very low productivity and low chlorophyll content needed for such production. Kayreyna is characterized by seagrasses with second highest chlorophyll content after Talim point, and in terms of productivity, two of seagrass species in this site E. acoroides and T. hemprichii are among those with the lowest R. Evidently, seagrasses in Talim Point, Shields Marine Station (the site which receives primarily agriculture run-off, i.e., near a creek that drains mostly

  2. Inversion of chlorophyll contents by use of hyperspectral CHRIS data based on radiative transfer model

    International Nuclear Information System (INIS)

    Chlorophyll content, the most important pigment related to photosynthesis, is the key parameter for vegetation growth. The continuous spectrum characteristics of ground objects can be captured through hyperspectral remotely sensed data. In this study, based on the coniferous forest radiative transfer model, chlorophyll contents were inverted by use of hyperspectral CHRIS data in the coniferous forest coverage of Changbai Mountain Area. In addition, the sensitivity of LIBERTY model was analyzed. The experimental results validated that the reflectance simulation of different chlorophyll contents was coincided with that of the field measurement, and hyperspectral vegetation indices applied to the quantitative inversion of chlorophyll contents was feasible and accurate. This study presents a reasonable method of chlorophyll inversion for the coniferous forest, promotes the inversion precision, is of significance in coniferous forest monitoring

  3. Quantification of plant chlorophyll content using Google Glass.

    Science.gov (United States)

    Cortazar, Bingen; Koydemir, Hatice Ceylan; Tseng, Derek; Feng, Steve; Ozcan, Aydogan

    2015-04-01

    Measuring plant chlorophyll concentration is a well-known and commonly used method in agriculture and environmental applications for monitoring plant health, which also correlates with many other plant parameters including, e.g., carotenoids, nitrogen, maximum green fluorescence, etc. Direct chlorophyll measurement using chemical extraction is destructive, complex and time-consuming, which has led to the development of mobile optical readers, providing non-destructive but at the same time relatively expensive tools for evaluation of plant chlorophyll levels. Here we demonstrate accurate measurement of chlorophyll concentration in plant leaves using Google Glass and a custom-developed software application together with a cost-effective leaf holder and multi-spectral illuminator device. Two images, taken using Google Glass, of a leaf placed in our portable illuminator device under red and white (i.e., broadband) light-emitting-diode (LED) illumination are uploaded to our servers for remote digital processing and chlorophyll quantification, with results returned to the user in less than 10 seconds. Intensity measurements extracted from the uploaded images are mapped against gold-standard colorimetric measurements made through a commercially available reader to generate calibration curves for plant leaf chlorophyll concentration. Using five plant species to calibrate our system, we demonstrate that our approach can accurately and rapidly estimate chlorophyll concentration of fifteen different plant species under both indoor and outdoor lighting conditions. This Google Glass based chlorophyll measurement platform can display the results in spatiotemporal and tabular forms and would be highly useful for monitoring of plant health in environmental and agriculture related applications, including e.g., urban plant monitoring, indirect measurements of the effects of climate change, and as an early indicator for water, soil, and air quality degradation. PMID:25669673

  4. Quantification of Plant Chlorophyll Content Using Google Glass

    OpenAIRE

    Cortazar, Bingen; Koydemir, Hatice Ceylan; Tseng, Derek; Feng, Steve; Ozcan, Aydogan

    2015-01-01

    Measuring plant chlorophyll concentration is a well-known and commonly used method in agriculture and environmental applications for monitoring plant health, which also correlates with many other plant parameters including, e.g., carotenoids, nitrogen, maximum green fluorescence, etc. Direct chlorophyll measurement using chemical extraction is destructive, complex and time-consuming, which has led to the development of mobile optical readers, providing non-destructive but at the same time rel...

  5. Qtl mapping of wheat doubled haploids for chlorophyll content and chlorophyll fluorescence kinetics under drought stress imposed at anthesis stage

    International Nuclear Information System (INIS)

    Drought stress is one of the major environmental constraints to crop plants including wheat worldwide. Synthetic hexaploid can act as a vehicle for improving crop tolerance against biotic and abiotic stresses. Doubled haploid population consisting of one hundred and forty individuals derived from cross of Opata and SH223 was used in the present study to identify genomic regions associated with various quantitative attributes of physiological nature. Doubled haploid mapping population was phenotyped for chlorophyll content and chlorophyll fluorescence kinetics under control and drought stress imposed at anthesis stage. Genotyping of population was accomplished by utilizing two hundred and sixty one polymorphic Gaterslaben wheat microsatellites and Beltsville agriculture research center simple sequence repeats. Linkage map of doubled haploid population comprising of 19 linkage groups and covering map length of two thousands six hundred and twenty six (2626) cM was constructed using map maker software. Major and minor QTLs associated with quantitative traits were identified using QGene software. Major QTL for chlorophyll content (QTc.wwc-1B-S11) of doubled haploid mapping population under anthesis drought stress was mapped on chromosome 1B and explained 10.09 percent of phenotypic variation at LOD score of 5.5. Seven major and minor QTLs for PCFK of doubled haploids were identified on chromosome 1B, 7A and 7D under control and drought stress at anthesis stage. The identified QTLs are of prime importance for high resolution mapping in synthetic hexaploid wheat. Genomic synteny of doubled haploids was observed with rice chromosome 2, 4, 7 and maize chromosome 7 owing to occurrence of orthologous QTLs for chlorophyll content and chlorophyll fluorescence respectively. (author)

  6. Inversion of a radiative transfer model for estimation of rice chlorophyll content using support vector machine

    Science.gov (United States)

    Lv, Jie; Yan, Zhenguo; Wei, Jingyi

    2014-11-01

    Accurate retrieval of crop chlorophyll content is of great importance for crop growth monitoring, crop stress situations, and the crop yield estimation. This study focused on retrieval of rice chlorophyll content from data through radiative transfer model inversion. A field campaign was carried out in September 2009 in the farmland of ChangChun, Jinlin province, China. A different set of 10 sites of the same species were used in 2009 for validation of methodologies. Reflectance of rice was collected using ASD field spectrometer for the solar reflective wavelengths (350-2500 nm), chlorophyll content of rice was measured by SPAD-502 chlorophyll meter. Each sample sites was recorded with a Global Position System (GPS).Firstly, the PROSPECT radiative transfer model was inverted using support vector machine in order to link rice spectrum and the corresponding chlorophyll content. Secondly, genetic algorithms were adopted to select parameters of support vector machine, then support vector machine was trained the training data set, in order to establish leaf chlorophyll content estimation model. Thirdly, a validation data set was established based on hyperspectral data, and the leaf chlorophyll content estimation model was applied to the validation data set to estimate leaf chlorophyll content of rice in the research area. Finally, the outcome of the inversion was evaluated using the calculated R2 and RMSE values with the field measurements. The results of the study highlight the significance of support vector machine in estimating leaf chlorophyll content of rice. Future research will concentrated on the view of the definition of satellite images and the selection of the best measurement configuration for accurate estimation of rice characteristics.

  7. Quantitative trait loci analysis of chlorophyll content for flag leaf in rice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Chlorophyll contents are one of important physiological traits, which affect photosynthesis in plants. There were significant differences in chlorophyll contents between Zhaiyeqing 8(ZYQ 8), an indica variety and Jingxi 17(JX 17), a japonica variety (Table 1). In 117 DH lines of the cross of ZYQ 8/ JX 17, these parameters distributed conTwo neutral alleles of improving male gamete abortion in indica-japonica hybrid rice LU Chuangen and ZOU Jiangshi, Jiangsu Acad of Agri Sci, Nanjing 210014, China

  8. Chlorophyll content and culture of flax embryos in vitro

    Directory of Open Access Journals (Sweden)

    A. Petrova

    2014-02-01

    Full Text Available During in vitro cultivation of green flax embryos excised 14 days after fertilization on White's medium the chloraphylls a and b are gradually destroyed and the lamellar system of plastids is disintegrated. It was possible, to prolong somewhat the presence of chlorophyll and to enhance embryo growth by culture in the dark and by adding kinetin. Light has a stimulating effect on the germination of embryos. Streptomycin inhibits chlorophyll synthesis not earlier than at germination. Young, green embryos are unable to sumvive and develop on media without sucrose. It is supposed that photosynthesis does not occur in flax embryos in vitro, and that green embryos are not more autotrophic in vitro than those of leucoembryophytes.

  9. Effect of Silicon on Leaf Ultrastructure,Chlorophyll Content and Photosynthetic Activity of Barley Under Salt Stress

    Institute of Scientific and Technical Information of China (English)

    LIANGYONGCHAO

    1998-01-01

    Two contrasting cultivars of barley(Hordeum vulgare L.):Kepin No.7(salt sensitive),and Jian 4(salt tolerant)were grown in a hydropon ics system with 2 NaCl levels:60 mmol NaCl L-1 and 120 mmol NaCl L-1 ,and 3 Si levels:0 mmol Si L-1 ,0.5 mmol Si L-1 and 1.0 mmol Si L-1 (as silicic acid).Compared with the plants treated with 60 mmol NaCl L-1 alone,the leaf chlorophyll contents of plants rreated with salt and Si increased significantly ofr salt-sensitive cultivar at tillering stage,but for alt-tolerant cultivar,the addition of Si resulted in an obivous increase in the leaf chlorophyll content of plants exposed to 120 mmol NaCl L-1 ,However,this Si-enhancement of leaf chlorophyll content was also observed in the salttolerant plants at joninting stage,but not in the salt-sensitive plants.Moreover,leaf chlorophyll content was consistently higher for the salt-tolerant cultivar than for the salt-sensitive cultivar irrespective of salt and/or Si treatment .Compared with the plants treated with sal alont ,net CO2 assimilation rate in plant leaves increased significantly for both cultivars when treated with salt and Si, Teh addition of Si to the salt teatment was found to improve the cell ultrastructure of leaves.Under salt stress condition,the double membranes of chloroplasts disappeared,but membrane integrity was markedly improved in the salt treatment supplemented with Si.Silicon was also found to ameliorate the damage to the ultrasturcture of chloroplast granae which appeared to be disintegrated and vague in salt treatments without added Si.The results support previous work which showed that Si decreases the permeability of plasma membranes of salt-stressed barley,thus mitigating salt damage.

  10. Beneficial role of spermidine in chlorophyll metabolism and D1 protein content in tomato seedlings under salinity-alkalinity stress.

    Science.gov (United States)

    Hu, Lipan; Xiang, Lixia; Li, Shuting; Zou, Zhirong; Hu, Xiao-Hui

    2016-04-01

    Polyamines are important in protecting plants against various environmental stresses, including protection against photodamage to the photosynthetic apparatus. The molecular mechanism of this latter effect is not completely understood. Here, we have investigated the effects of salinity-alkalinity stress and spermidine (Spd) on tomato seedlings at both physiological and transcriptional levels. Salinity-alkalinity stress decreased leaf area, net photosynthetic rate, maximum net photosynthetic rate, light saturation point, apparent quantum efficiency, total chlorophyll, chlorophyll a and chlorophyll a:chlorophyll b relative to the control. The amount of D1 protein, an important component of photosystem II, was reduced compared with the control, as was the expression of psbA, which codes for D1. Expression of the chlorophyll biosynthesis gene porphobilinogen deaminase (PBGD) was reduced following salinity-alkalinity stress, whereas the expression of Chlase, which codes for chlorophyllase, was increased. These negative physiological effects of salinity-alkalinity stress were alleviated by exogenous Spd. Expression of PBGD and psbA were enhanced, whereas the expression of Chlase was reduced, when exogenous Spd was included in the stress treatment compared with when it was not. The protective effect of Spd on chlorophyll and D1 protein content during stress may maintain the photosynthetic apparatus, permitting continued photosynthesis and growth of tomato seedlings (Solanum lycopersicum cv. Jinpengchaoguan) under salinity-alkalinity stress. PMID:26477612

  11. Effect of drought stress on yield, proline and chlorophyll contents in three chickpea cultivars

    NARCIS (Netherlands)

    Mafakheri, A.; Siosemardeh, A.; Bahramnejad, B.; Struik, P.C.; Sohrabi, Y.

    2010-01-01

    Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effect of drought stress on proline content, chlorophyll content, photosynthesis and transpiration, stomatal conductance and yield characteristics in three varieties of chickpe

  12. Plant Leaf Chlorophyll Content Retrieval Based on a Field Imaging Spectroscopy System

    Directory of Open Access Journals (Sweden)

    Bo Liu

    2014-10-01

    Full Text Available A field imaging spectrometer system (FISS; 380–870 nm and 344 bands was designed for agriculture applications. In this study, FISS was used to gather spectral information from soybean leaves. The chlorophyll content was retrieved using a multiple linear regression (MLR, partial least squares (PLS regression and support vector machine (SVM regression. Our objective was to verify the performance of FISS in a quantitative spectral analysis through the estimation of chlorophyll content and to determine a proper quantitative spectral analysis method for processing FISS data. The results revealed that the derivative reflectance was a more sensitive indicator of chlorophyll content and could extract content information more efficiently than the spectral reflectance, which is more significant for FISS data compared to ASD (analytical spectral devices data, reducing the corresponding RMSE (root mean squared error by 3.3%–35.6%. Compared with the spectral features, the regression methods had smaller effects on the retrieval accuracy. A multivariate linear model could be the ideal model to retrieve chlorophyll information with a small number of significant wavelengths used. The smallest RMSE of the chlorophyll content retrieved using FISS data was 0.201 mg/g, a relative reduction of more than 30% compared with the RMSE based on a non-imaging ASD spectrometer, which represents a high estimation accuracy compared with the mean chlorophyll content of the sampled leaves (4.05 mg/g. Our study indicates that FISS could obtain both spectral and spatial detailed information of high quality. Its image-spectrum-in-one merit promotes the good performance of FISS in quantitative spectral analyses, and it can potentially be widely used in the agricultural sector.

  13. Plant leaf chlorophyll content retrieval based on a field imaging spectroscopy system.

    Science.gov (United States)

    Liu, Bo; Yue, Yue-Min; Li, Ru; Shen, Wen-Jing; Wang, Ke-Lin

    2014-01-01

    A field imaging spectrometer system (FISS; 380-870 nm and 344 bands) was designed for agriculture applications. In this study, FISS was used to gather spectral information from soybean leaves. The chlorophyll content was retrieved using a multiple linear regression (MLR), partial least squares (PLS) regression and support vector machine (SVM) regression. Our objective was to verify the performance of FISS in a quantitative spectral analysis through the estimation of chlorophyll content and to determine a proper quantitative spectral analysis method for processing FISS data. The results revealed that the derivative reflectance was a more sensitive indicator of chlorophyll content and could extract content information more efficiently than the spectral reflectance, which is more significant for FISS data compared to ASD (analytical spectral devices) data, reducing the corresponding RMSE (root mean squared error) by 3.3%-35.6%. Compared with the spectral features, the regression methods had smaller effects on the retrieval accuracy. A multivariate linear model could be the ideal model to retrieve chlorophyll information with a small number of significant wavelengths used. The smallest RMSE of the chlorophyll content retrieved using FISS data was 0.201 mg/g, a relative reduction of more than 30% compared with the RMSE based on a non-imaging ASD spectrometer, which represents a high estimation accuracy compared with the mean chlorophyll content of the sampled leaves (4.05 mg/g). Our study indicates that FISS could obtain both spectral and spatial detailed information of high quality. Its image-spectrum-in-one merit promotes the good performance of FISS in quantitative spectral analyses, and it can potentially be widely used in the agricultural sector. PMID:25341439

  14. Analysis of quantitative trait loci underlying the traits related to chlorophyll content of the flag leaf in rice

    Institute of Scientific and Technical Information of China (English)

    Guohua YANG; Sansi TU; Shaoqing LI; Lingling FENG; Jin KONG; Hui LI; Yangsheng LI

    2008-01-01

    A population of 117 doubled haploid (DH) lines derived from the cross of Zhaiyeqing 8 (indica) x Jingxi 17 (japonica) was employed to map quantitative trait loci (QTL) underlying four physiological traits related to chlorophyll contents of the flag leaf. There were significantly positive correlations among chlorophyll a, chlorophyll b and chlorophyll a+ b content. Chlorophyll a/b ratio was significantly negatively correlated with chlorophyll b content. These four traits were normally distributed with transgressive segregation, suggesting that they were controlled by multiple minor genes. A total of 11 QTLs were detected for the four traits and they lay on six chromosomes. Each of them explained 9.2%-19.6% of the phenotypic variations, respectively. Of these, two QTLs controlling chlorophyll a content were mapped on chromosomes 2 and 5; four QTLs underlying chlorophyll b content were mapped on chromosomes 2, 3, 5 and 9; three QTLs underlying chlorophyll a+b amount were mapped on chromosomes 3, 5 and 9; two QTLs under-lying chlorophyll a/b ratio were mapped on chromosomes 6 and 1 1. The intrinsic relationship among the four traits and the practical implication in rice breeding are discussed.

  15. Spectrometric estimation of the content of chlorophyll in plants subjected to anthropogenic action

    Science.gov (United States)

    Quliev, R. B.; Azizov, B. M.; Abbaszadeh, A. A.

    2009-03-01

    Spectral methods for determining the content of chlorophyll in vegetation subjected to anthropogenic action are considered. The regularities in the changes in the spectral radiance coefficients of vegetation in certain intervals of the visible range are considered in relation to the degree of remoteness of the pollution source.

  16. Predicting chlorophyll content of greenhouse tomato with ground-based remote sensing

    Science.gov (United States)

    Ding, Yong-jun; Li, Min-zan; Li, Shu-qiang; An, Deng-kui

    2010-11-01

    NIR spectroscopy can be used in analysis of plant chlorophyll content on a large scale area. This offers the opportunity to use spectral reflectance as a non-destructive method for analyzing photosynthetic pigment status in plant. This research studied the variation of the chlorophyll content and spectral response at different growth stages of greenhouse tomato. Leaf spectral measurements from each treatment (4 N-levels: 0%, 33.3%, 66.6%, 100%) were taken in the greenhouse using an ASD FieldSpec HH spectrophotometer. Chlorophyll content of tomato leaves were measured by alcoholic-acetone extraction in lab. It was found that chlorophyll content of tomato leaf was increasing continuously to the maximum 50 days after the transplantation, while red edge moved to the NIR bands (long wave), and green peak position moved to the Blue bands (short wave) and green peak amplitude decreased. The chlorophyll content would decrease after fruiting stage, while red edge, green peak position and amplitude moved to the opposite direction. Regarding quantitative analysis the relationship between chlorophyll content and spectral response, red edge parameters (Sred(area of red edge), Dred (amplitude of red edge) and Pred (position of red edge ) ) in the first derivative of reflectance curve were obtained at bands of 680-760 nm. Similarly, blue edge, green peak and red valley parameters were defined to reflect spectral character. Vegetation indices were used extensively to estimate the vegetation growth status. Thus, the following wavelengths were used for developing RVI, NDVI and ARVI indices: λ440nm, λ500nm, λ550nm, λ680nm, λ770nm, Pblue (position of blue edge), Pyellow (position of yellow edge), Pred (position of red edge), Pgreenpeak (position of green peak), Predvalley (position of red valley). Seven optimal spectral parameters were chosen with the method of Karhunen-Loeve from the above-mentioned 68 self-defined property parameters. Stepwise multiple regression (SMLR

  17. Effect of drought stress on yield, proline and chlorophyll contents in three chickpea cultivars

    OpenAIRE

    Mafakheri, A.; Siosemardeh, A.; Bahramnejad, B.; Struik, P.C.; Sohrabi, Y. (Yahya)

    2010-01-01

    Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effect of drought stress on proline content, chlorophyll content, photosynthesis and transpiration, stomatal conductance and yield characteristics in three varieties of chickpea (drought tolerant Bivaniej and ILC482 and drought sensitive Pirouz). A field experiment with four irrigation regimes was carried out in a randomized complete block design with three replications....

  18. Soil Salinity Alters Growth, Chlorophyll Content, and Secondary Metabolite Accumulation in Catharanthus roseus

    OpenAIRE

    Jaleel, Cheruth Abdul; SANKAR, Beemarao; SRIDHARAN, Ramalingam

    2008-01-01

    The effect of salinity on growth, photosynthetic pigment content, and alkaloid secondary metabolite accumulation were studied in an economically important medicinal plant, Catharanthus roseus (L.) G. Don., under pot culture conditions. Plants were treated with different concentrations of NaCl, (e.g. 50 and 100 mM) 30, 45, 60, and 75 days after sowing (DAS). The plants were uprooted randomly 90 DAS to analyse growth, and chlorophyll and alkaloid content. Salinity affected all the morphological...

  19. The evaluation of fish farming impact by nutrient content and chlorophyll A in Mala Lamljana bay

    Directory of Open Access Journals (Sweden)

    Jelic-Mrcelic Gorana

    2013-01-01

    Full Text Available This paper offers a brief review of the impacts of fish farming on the nutrient content and chlorophyll a in Mala Lamljana Bay, Croatia. Local loading of nitrogen and phosphorous compounds in fish farms can be very significant and can represent the largest source of N and P in a given area. Low N and P concentrations, low chlorophyll a concentration and a great variety of phytoplankton species were found in the bay, despite the high nutrient loading during the long history of farming in the bay. The phytoplankton community consisted mostly of diatoms and partly of dinoflagellates. Skeletonema costatum and Chaetoceros compressus were the dominant species (90% in summer chlorophyll, which is typical for Middle Adriatic oligotrophic coastal waters. Nevertheless, further studies are required to determine changes in water column factors and planktonic communities in this area.

  20. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

    Science.gov (United States)

    Chen, Xueqing; Pei, Yuansheng

    2016-10-01

    Sodium pentaborate pentahydrate (SPP) is a rare mineral. In this study, SPP was synthesized from boric acid and borax through low-temperature crystallization, and its effects on the growth of the alga, Chlorella vulgaris (C. vulgaris) were assessed. The newly synthesized SPP was characterized by chemical analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential thermal analysis. The changes in C. vulgaris growth, chlorophyll content, and enzyme activities upon exposure to SPP for 168h were evaluated. Results showed that SPP treatment was detrimental to C. vulgaris growth during the first 24-120h of exposure. The harmful effects, however, diminished over time (168h), even at an effective medium concentration of 226.37mg BL(-1) (the concentration of boron applied per liter of culture medium). A similar trend was observed for chlorophyll content (chlorophyll a and b) and indicated that the photosynthesis of C. vulgaris was not affected and that high levels of SPP may even promote chlorophyll synthesis. Superoxide dismutase and catalase activities of C. vulgaris increased during 24-120h exposure to SPP, but these activities gradually decreased as culture time progressed. In other words, the initial detrimental effects of synthetic SPP on C. vulgaris were temporary and reversible. This research provides a scientific basis for applications of SPP in the environment. PMID:27367150

  1. Protein and Chlorophyll Contents of Solanum melongena on Diesel Oil Polluted Soil Amended with Nutrient Supplements

    OpenAIRE

    C.O. Akujobi; R.A. Onyeagba; V.O. Nwaugo; N.N. Odu

    2011-01-01

    The study investigated the remediation effect of nutrient amendments of diesel oil polluted soil on protein and chlorophyll contents of eggplant (Solanum melongena). Soil samples were polluted and amended separately with different weights of poultry waste, pig waste, cow dung and inorganic fertilizer. Soil samples were also polluted with diesel oil without amendment to achieve 2, 4, 6, 8 and 10% pollution. Samples were analyzed at two weeks interval for sixteen weeks. The plant protein and ch...

  2. Evaluation of Chlorophyll Content and Fluorescence Parameters as Indicators of Drought Tolerance in Barley

    Institute of Scientific and Technical Information of China (English)

    LI Rong-hua; GUO Pei-guo; Michael Baum; Stefania Grando; Salvatore Ceccarelli

    2006-01-01

    Drought is a major abiotic stress that severely affects food production worldwide. Agronomic and physiological traits associated with drought tolerance are suitable indicators for selection of drought tolerance genotypes to reduce the impact of water deficit on crop yield in breeding program. The objective of this study was to identify indicators related to drought tolerance through analysis of photosynthetic traits in barley (Hordeum vulgare L.). These traits included chlorophyll content, initial fluorescence (Fo), maximum primary yield of photochemistry of pho tosystem Ⅱ (Fv / Fo) and maximum quantum yield of photosystem Ⅱ (Fv/Fm). Four genotypes (Tadmor, Arta, Morocco9-75 and WI2291) variable in drought tolerance were used to investigate the correlation between these traits and drought tolerance. The results reflected that all of these traits were affected negatively in the four genotypes at different levels of post-anthesis drought stress, but the decrease in drought tolerant genotypes was much less than that of drought sensitive genotypes. The results further revealed that the components of the photosynthetic apparatus could be damaged significantly in drought sensitive genotypes, while drought tolerant genotypes were relatively less affected. On the other hand, the values of chlorophyll content, Fo, Fv/Fo and Fv/Fm in drought tolerance genotypes were significantly higher than those in drought sensitive genotypes under drought stress. It was concluded that chlorophyll content, Fo, Fv / Fo and Fv / Fm could be considered as reliable indicators in screening barley germplasm for drought tolerance.

  3. Photosynthesis rate, chlorophyll content and initial development of physic nut without micronutrient fertilization

    Directory of Open Access Journals (Sweden)

    Elcio Ferreira dos Santos

    2013-10-01

    Full Text Available Few studies in Brazil have addressed the need for micronutrients of physic nut focusing on physiological responses, especially in terms of photosynthesis. The objective of this study was to evaluate the effects of omission of boron (B, copper (Cu, iron (Fe, manganese (Mn and zinc (Zn on Jatropha curcas L.. The experimental design was a randomized block with four replications. The treatments were complete solution (control and solution without B, Cu, Fe, Mn, and Zn. We evaluated the chlorophyll content (SPAD units, photosynthetic rate, dry matter production and accumulation of micronutrients in plants, resulting from different treatments. The first signs of deficiency were observed for Fe and B, followed by Mn and Zn, while no symptoms were observed for Cu deficiency. The micronutrient omission reduced the dry matter yield, chlorophyll content and photosynthetic rate of the plants differently for each omitted nutrient. It was, however, the omission of Fe that most affected the development of this species in all parameters evaluated. The treatments negatively affected the chlorophyll content, evaluated in SPAD units, and the photosynthetic rate, except for the omission of B. However this result was probably due to the concentration effect, since there was a significant reduction in the dry matter production of B-deficient plants.

  4. Growth, chlorophyll content and combined output value in eggplant/garlic relay intercropping systems

    International Nuclear Information System (INIS)

    A plastic tunnel experiment was conducted to investigate the effect of eggplant/garlic relay intercropping on the eggplant growth, chlorophyll content and combined output value in 2011 and 2012. The experimental design was randomized block with three replications consisting of eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). It is showed that the eggplant stem in 2011 was first thicker then thinner in CK than NG, and it was always thicker in CK than GG; the plant height and stem diameter were both higher in relay intercropping treatments than CK in 2012. The chlorophyll content and chlorophyll a/b ratio were lower in NG compared with CK in most cases. In 2011, the eggplant yield and combined output value in GG were lower than CK, but in 2012, they were higher and the difference of combined output value between GG and CK was significant; for NG, they were always promoted both in 2011 and 2012. Different results between 2011 and 2012 may be due to the different time of green garlic uprooted in the spring. It is proved that uprooting green garlic before eggplant transplanting in 2012 was better to eggplant growth than uprooting them after eggplant transplanting in 2011. The conclusions are drawn that relay intercropping with normal or green garlic can improve the eggplant growth, increase the yield and the combined output value. As a result, eggplant/garlic relay intercropping systems may contribute to sustainable production of eggplant. (author)

  5. Protein and Chlorophyll Contents of Solanum melongena on Diesel Oil Polluted Soil Amended with Nutrient Supplements

    Directory of Open Access Journals (Sweden)

    C.O. Akujobi

    2011-09-01

    Full Text Available The study investigated the remediation effect of nutrient amendments of diesel oil polluted soil on protein and chlorophyll contents of eggplant (Solanum melongena. Soil samples were polluted and amended separately with different weights of poultry waste, pig waste, cow dung and inorganic fertilizer. Soil samples were also polluted with diesel oil without amendment to achieve 2, 4, 6, 8 and 10% pollution. Samples were analyzed at two weeks interval for sixteen weeks. The plant protein and chlorophyll were affected adversely by the diesel oil pollution and the higher the level of pollution, the more the effect. The nutrient amendments were able to remedy the effect of the diesel oil pollution. The remediation effect was nutrient weight dependent and the best remediation effect was observed in poultry waste amended samples. This study has shown that diesel oil contaminated soil may have adverse effect on the protein and chlorophyll contents of plants, but this can be remedied by addition of organic nutrient supplements especially poultry waste.

  6. Differentiation between heterotrophic and photosynthetic plankton by size fractionation, glucose uptake, ATP and chlorophyll content

    International Nuclear Information System (INIS)

    By means of a technique which included 3H-D-glucose uptake, ATP and chlorophyll analyses in different size fractions of lake water microorganisms, the bacterial and the phytoplankton biomasses were estimated from four eutrophic lakes. Short term glucose uptake experiments and chlorophyll analyses in lake water used as indicators of the bacteria and the phytoplankton present in the different size fractions, whereas ATP measurements were used to quantify their respective biomasses. The bacteria comprised between 3 and 18% of total biomass (phytoplankton + bacteria) and between 50 and 90% of the bacteria were free-living. The numbers of bacteria calculated from the bacterial ATP content were 20 to 50% higher than the numbers estimated by direct counting. (author)

  7. Chlorophyll content mapping of urban vegetation in the city of Valencia based on the hyperspectral NAOC index

    OpenAIRE

    Delegido, Jesús; Van Wittenberghe, Shari; Verrelst, Jochem; Ortiz, Violeta; Veroustraete, Frank; Valcke, Roland; Samson, Roeland; Rivera, Juan P.; Tenjo, Carolina; Moreno, José

    2014-01-01

    Spatially distributed chlorophyll content of urban vegetation provides an important indicator of a plant's health status, which might depend on the habitat quality of the specific urban environment. Recent advances in optical remote sensing led to improved methodologies to monitor vegetation properties. The hyperspectral index NAOC (Normalized Area Over reflectance Curve) is one of these new tools that can be used for mapping chlorophyll content. In this paper we present the work done to quan...

  8. Biomass, chlorophyll and nitrogen content of leaves of two chili pepper varieties (Capsicum annum) in different fertilization treatments

    OpenAIRE

    SUTARNO; SUHARJA

    2009-01-01

    Suharja, Sutarno. 2009. Biomass, chlorophyll and nitrogen content of leaves of two chili pepper varieties (Capsicum annum) in different fertilization treatments. Nusantara Bioscience 1: 9-16. This study aims to determine the influence of various fertilization treatments on biomass, chlorophyll and nitrogen content of leaves from two varieties of chili, Sakti (large chili) and Fantastic (curly chili). The study was conducted in the village of Gatak, Karangnongko sub-district, Klaten District, ...

  9. Chlorophyll and pheophytin content in needles of different age of trees growing under conditions of chronic industrial pollution

    Directory of Open Access Journals (Sweden)

    Teresa Gowin

    2015-05-01

    Full Text Available Chlorophyll and pheophytin content was determined by means of Vernon method (Vernon, 1960 in needles of different age. Needles of Pinus strobus L., Pinus nigra Arnd., Pinus silvestris L., and Pseudotsuga menziesii Franco growing under conditions of chronic industrial pollution as well as under unpolluted conditions were examined. High pheophytin content was found in needles of trees growing under the conditions of chronic pollution. The youngest needles always showed the highest pheophytin content' as related to Chlorophyll content. The examined species showed different degree of Chlorophyll decomposition under the influence of polluted environment. Trees growing under control environment showed small and similar amounts of pheophytin in needles of different age. Pheophytin content does not seem to be a convenient indicator to test the effect of pollution before visual symptoms occur, since the method is very labourious and plant material very variable.

  10. Variation in Chlorophyll Content per Unit Leaf Area in Spring Wheat and Implications for Selection in Segregating Material

    OpenAIRE

    John Hamblin; Katia Stefanova; Tefera Tolera Angessa

    2014-01-01

    Reduced levels of leaf chlorophyll content per unit leaf area in crops may be of advantage in the search for higher yields. Possible reasons include better light distribution in the crop canopy and less photochemical damage to leaves absorbing more light energy than required for maximum photosynthesis. Reduced chlorophyll may also reduce the heat load at the top of canopy, reducing water requirements to cool leaves. Chloroplasts are nutrient rich and reducing their number may increase availab...

  11. Development of the spectrometric imaging apparatus of laser induced fluorescence from plants and estimation of chlorophyll contents of rice leaves; Laser reiki keiko sokutei sochi no kaihatsu to inehanai no chlorophyll ganryo no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Nakaya, K.; Shoji, K.; Hanyu, H.

    1999-05-01

    Photosynthetic activity of plants is an important factor to assess the micrometeorological effect of plant canopy or to estimate the influence of circumstances such as water stress. Light illumination induces fluorescence from a leaf or suspension of chloroplasts. The red chlorophyll fluorescence had been used to determine the process of the electron transportation in photosynthetic reaction. The fluorescence source other than chlorophyll is not announced sufficiently, but is supposed to be useful to determine the contents of the substance corresponding to physiological response of plants. We developed a fluorescence imaging apparatus to observe spectrum and distribution of laser induced fluorescence from a leaf. Pulsed UV-laser (Nd:YAG) induced blue-green fluorescence and red chlorophyll fluorescence from a green leaf. The pulse modulated measuring light and CCD with image-intensifier (ICCD) enable to detect the fluorescence from plants under illumination. The laser induced fluorescence (LIF) spectra were investigated to estimate the chlorophyll contents in leaves of rice. During the greening course of dark grown etiolated rice leaves, chlorophyll contents were determined using the extraction of leaves and steady state LIF spectra were measured. As a result, the ratio of fluorescent intensity between blue-green and red peaks (F460/F740 and F510/F740) decreased in proportion to alteration of chlorophyll contents respectively. These fluorescence intensity ratios perform more precise estimation of higher chlorophyll contents of leaves than reported red chlorophyll fluorescence intensity ratio (F690/E740). (author)

  12. Quantitative Trait Loci Mapping of Leaf Morphological Traits and Chlorophyll Content in Cultivated Tetraploid Cotton

    Institute of Scientific and Technical Information of China (English)

    Xian-Liang SONG; Wang-Zhen GUO; Zhi-Guo HAN; Tian-Zhen ZHANG

    2005-01-01

    Genetic mapping provides a powerful tool for quantitative trait loci (QTL) analysis at the molecular level. A simple sequence repeat (SSR) genetic map containing 590 markers and a BC1 population from two cultivated tetraploid cotton (Gossypium hirsutum L.) cultivars, namely TM-1 and Hai 7124 (G.barbadense L.), were used to map and analyze QTL using the composite interval mapping (CIM) method.Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content,were detected on 15 chromosomes or linkage groups at logarithm of odds (LOD) ≥ 2.0, of which 15 were found for leaf morphology at LOD ≥.3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection (MAS) of these traits in tetraploid cotton breeding.

  13. Effects of Different Nitrogen Forms on the Contents of Chlorophyll and Mineral Elements in Chinese chive Seedlings

    Directory of Open Access Journals (Sweden)

    Yongdong Sun

    2014-05-01

    Full Text Available Chinese chive is an important leafy vegetable, for which nitrogen is vital for growth, development and nutritional quality. In order to study the effects of improved hoagland nutrient solution with different nitrate (NO3- to ammonium (NH4+ ratios (25:75, 50:50, 75:25 and 100:0 on the contents of chlorophyll and mineral elements (Ca, Fe, Zn, Cu, Mn, Mg and K for three cultivars, Saisong, Pingjiu No.4 and Pingjiu No.8, under 14 mmol/L nitrogen. An experiment was conducted at experimental plots and lab of the school of horticulture and landscape architecture, henan institute of science and technology. The results showed that the chlorophyll a, chlorophyll b and total chlorophyll of the three cultivars were all reached a maximum value with NO3- and NH4+ ratio of 50:50. The eight mineral elements contents were higher for three cultivars at a NO3- and NH4+ ratios of 50:50 and 75:25. It could be concluded that the NO3- and NH4+ ratio of 50:50 effectively improved the chlorophyll contents and promoted accumulation of mineral elements in Chinese chive under hydroponic culture and was the optimal ratio.

  14. Effect of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings

    Science.gov (United States)

    Rupiasih, N. Nyoman; Vidyasagar, Pandit B.

    2016-03-01

    An investigation of the effects of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings has been done. The UV-C irradiation periods of exposure were 30, 60, 90, 120 and 180 minutes. The hypergravity used were 1000 g, 2000 g and 2500 g. The combination treatment is UV-C irradiation for 180 min followed by each hypergravity. The results showed that irradiation of UV-C on wheat seeds have stimulated the seed germination, but hypergravity and combination treatments on wheat seeds have inhibited the seed germination. Those treatments gave negative effects to growth rate, the content of chlorophyll a, b and total chlorophyll of wheat seedlings.

  15. Sensitivity of Ground-Based Remote Sensing Estimates of Wheat Chlorophyll Content to Variation in Soil Reflectance

    Science.gov (United States)

    Most ground-based optical sensors utilize spectral indices (SI) to estimate wheat (Triticum aestivum L.) chlorophyll a and b content (Cab) critical for advising in-season nitrogen fertilizer needs. These indices are sensitive to Cab, leaf area index (LAI), and soil background variation, but relative...

  16. Changes in chlorophyll content and fluorescence and fruit yield contributing traits in different genotypes of strawberry (Fragaria x ananassa DUCH.)

    OpenAIRE

    Elżbieta Kaczmarska; Władysław Michałek

    2014-01-01

    Analysis of changes in chlorophyll fluorescence parameters in strawberry leaves was based on a field experiment performed in the years 2009–2010. Ten genotypes including 5 cultivars: ‘Kent’, ‘Teresa’, ‘Senga Sengana’, ‘Chandler’ and the breeding clone 1387 as well as their inbred progeny, were the object of the study. During the experiment the following indicators were evaluated: chlorophyll a and b content in fresh leaf mass as well as fluorescence parameters: minimum (F0) and maximum fluore...

  17. Chlorophyll and pheophytin content in needles of different age of trees growing under conditions of chronic industrial pollution

    OpenAIRE

    Teresa Gowin; Igor Góral

    2015-01-01

    Chlorophyll and pheophytin content was determined by means of Vernon method (Vernon, 1960) in needles of different age. Needles of Pinus strobus L., Pinus nigra Arnd., Pinus silvestris L., and Pseudotsuga menziesii Franco growing under conditions of chronic industrial pollution as well as under unpolluted conditions were examined. High pheophytin content was found in needles of trees growing under the conditions of chronic pollution. The youngest needles always showed the highest pheophytin c...

  18. RELATIVE CHLOROPHYLL CONTENT CHANGES DURING UPTAKING OF SELENITE AND SELENATE BY MAIZE PLANTS GROWN IN NUTRIENT SOLUTION

    Directory of Open Access Journals (Sweden)

    Farzaneh Garousi

    2015-02-01

    Full Text Available Chlorophyll content (chl, one of the most important physiological parameters related to plant photosynthesis, is usually used to predict plant potential and portable, non-destructive chlorophyll meters could be a valuable and effective tool for estimating Relative Chlorophyll Content (RCC in leaves. In this study, two species of soluble inorganic Selenium forms, selenite (SeIV and selenate (SeVI at different concentrations were investigated on maize plants that were growing in nutrient solutions during 2 weeks and changes of RCC within this time was monitored. It means chlorophyll content of three leaves of maize when everyone grew completely was measured according to Special Products Analysis Division (SPAD value and the results revealed that high concentrations of SeIV (10, 30 and 90 mg.kg-1 were toxic for maize even lower amounts (1 and 3 mg.kg-1 had effects of damage on it while this state wasn’t adjusted for lower concentrations of SeVI (1 and 3 mg.kg-1 and treated samples didn’t have significant differences with controls although in higher amounts (10 and 30 mg.kg-1 toxic effects were seen in them, too.

  19. Three-band model for noninvasive estimation of chlorophyll, carotenoids, and anthocyanin contents in higher plant leaves

    Science.gov (United States)

    Gitelson, Anatoly A.; Keydan, Galina P.; Merzlyak, Mark N.

    2006-06-01

    Leaf pigment content and composition provide important information about plant physiological status. Reflectance measurements offer a rapid, nondestructive technique to estimate pigment content. This paper describes a recently developed three-band conceptual model capable of remotely estimating total of chlorophylls, carotenoids and anthocyanins contents in leaves from many tree and crop species. We tuned the spectral regions used in the model in accord with pigment of interest and the optical characteristics of the leaves studied, and showed that the developed technique allowed accurate estimation of total chlorophylls, carotenoids and anthocyanins, explaining more than 91%, 70% and 93% of pigment variation, respectively. This new technique shows a great potential for noninvasive tracking of the physiological status of vegetation and the impact of environmental changes.

  20. The Effect of Different Waterlogging Period on Chlorophyll Content, Dry Matter and Leaf Area at Bread Wheat Seedling

    OpenAIRE

    TİRYAKİOĞLU, Murat; KARANLIK, Sema; ASLANYÜREK, Derviş

    2014-01-01

    Effects of different periods of flooding on plant green area, dry matter production and leaf chlorophyll content were studied inwheat (Dağdaş cv, Triticum aestivum L.) in hydroponic under the controlled conditions. Resultsshowed thatleaf area and shoot dry matter were reduced with flooding when compared to control, and this effect was being more remarkablewith increasing in duration of flooding. Subsequent to the application of flooding, application of oxygen provided an improvementin leaf a...

  1. Foliar resorption and chlorophyll content in leaves of Cistus creticus L. (Cistaceae) along an elevational gradient in Turkey

    OpenAIRE

    Turkis, Sevda; Özbucak, Tugba Bayrak

    2010-01-01

    Foliar nitrogen and phosphorus dynamics, leaf resorption efficiency, proficiency, changing of chlorophyll a/b proportions in leaves of Cistus creticus L. (Cistaceae) along an elevational gradient (sea level-30 m, middle-670 m, high- 80 m) were investigated. Statistically significant differences were found in foliar nitrogen and phosphosrus content in terms of growth periods, while no significant differences were found according to elevations. Nitrogen and phosphorus resorption efficiency and ...

  2. Biomass, chlorophyll and nitrogen content of leaves of two chili pepper varieties (Capsicum annum in different fertilization treatments

    Directory of Open Access Journals (Sweden)

    SUTARNO

    2009-03-01

    Full Text Available Suharja, Sutarno. 2009. Biomass, chlorophyll and nitrogen content of leaves of two chili pepper varieties (Capsicum annum in different fertilization treatments. Nusantara Bioscience 1: 9-16. This study aims to determine the influence of various fertilization treatments on biomass, chlorophyll and nitrogen content of leaves from two varieties of chili, Sakti (large chili and Fantastic (curly chili. The study was conducted in the village of Gatak, Karangnongko sub-district, Klaten District, Central Java in September 2006 to March 2007. The study used a complete block design with two factorial of chili varieties and fertilizer treatment. Fertilization treatments includes no fertilizer (control (P1; manure 2 kg/plant (P2, manure (1 kg/plant + chemical fertilizer (ZA, SP-36, KCl = 2: 1: 1 + NPK (P3; and manure (1 kg/plant + chemical fertilizer (SP-36: KCl = 1:1 + liquid organic fertilizer (P4. Chlorophyll content was measured refers to Harborne (1987, whereas leaf nitrogen concentration was measured with Kjeldahl method. Data were analyzed using ANOVA followed by DMRT. The results showed that on the Fantastic chili fertilizer treatment affected the biomass and chlorophyll a, but gave no effect on chlorophyll b, total chlorophyll and leaf nitrogen. On the curly chili fertilizer treatment effected plant fresh weight, chlorophyll a and total chlorophyll, but gave no effect on dry weight, fresh fruit weight, chlorophyll b and leaf nitrogen. It is, therefore, recommended to use the formulation of manure + chemical fertilizer (SP-36: KCl = 1: 1 + liquid organic fertilizer in the cultivation of chili.Key words: biomass, chlorophyll, leaf nitrogen, chili, Capsicum annum, fertilizing.Abstrak. Suharja, Sutarno. 2009. Biomassa, kandungan klorofil dan nitrogen daun dua varietas cabai (Capsicum annum pada berbagai perlakuan pemupukan. Nusantara Bioscience 1: 9-16. Penelitian ini bertujuan untuk mengetahui pengaruh berbagai perlakuan pemupukan terhadap biomassa

  3. The effect of different uranium concentrations on physiological characteristics and chlorophyll contents in sunflowers and soy bean

    International Nuclear Information System (INIS)

    Uranium as a natural radioactive heavy metal, widely disperses throughout the earth's crust. In many cases, the natural abundance has been re-distributed due to anthropogenic activities, resulting in radionuclide contamination in groundwater and surface soil. A pot experiment had been conducted in the Agricultural College Research Greenhouse, at the Ferdowsi University of Mashhad under the controlled condition. The effect of six levels of uranium (0, 50, 100, 250, 500 and 1000 mg U kg-1) on physiological characteristics and chlorophyll contents in sunflower and soy bean were studied in a completely randomized design as a factorial experiment with three replications. Plants were harvested after 40 days and before the reproductive stages. Root and stem length, root dry weight, stem dry weight, biomass and chlorophyll contents were determined. The shoot and root length, fresh and dry mass as well as leaf area and chlorophyll contents showed a significant negative correlation with the applied uranium concentrations. The influence on plant growth was also measured in terms of tolerance index and grade of growth inhibition. The results showed that tolerance index increased and grade od growth inhibition decreased with the applied uranium concentration. Biomass and tolerance of sunflower during the experiment on higher uranium concentrations showed that sun flower is more resistant against uranium toxicity

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

    Directory of Open Access Journals (Sweden)

    Renato Contillo

    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.

  5. Studying of Salinity Stress Effect on Germination, Proline, Sugar, Protein, Lipid and Chlorophyll Content in Purslane (Portulaca oleracea L. Leaves

    Directory of Open Access Journals (Sweden)

    Parvaneh Rahdari

    2012-04-01

    Full Text Available Approximately 30% of country regions are under influence of salt and one of the main important methods for increasing of hectare performance in salt soils, using of resistant plant against with salt such as medicinal annual plant of Purslane (Portulaca oleraceae L..Studying of the salt stress effect on germination and some physiological parameters in Purslane was carried out in completely random framework and with three replications and under controlled conditions. In this study, salinity was imposed by sodium chloride (NaCl and in five levels of framework included of Control (distilled water, 50, 100, 150 and 200 Mmol from NaCl. Studied physiological parameters included of proline, sugar, protein, lipid and chlorophyll in Purslane leaves.In relation with observed germination that increasing of salt level, germination rate was reduced that the least germination rate in 200 Mmol and the highest germination was observed in control which in statistical level 0.01 showed meaningful difference. Also, results showed an increasing of leaf proline and sugar that was synchronize with increasing of sodium chloride, this increasing in statistical level of P<0.01 was meaningful, while blank had the least rate and salt level 200 Mmol was observed. Synchronize with increasing of salinity level, lipid and protein concentration decreasing that was meaningful (P<0.01 which highest of leaf lipid and protein content in control level and least concentration was observed in 200 Mmol of salinity level. Also, salinity stress due to increasing of chlorophyll a and b levels in Purslane leaves which this increasing in leaf chlorophyll b concentrations in 0.01 statistical level was meaningful and the least level chlorophyll a and b in blank and the highest level of chlorophyll a and b by order in 150 and 200 Mmol of NaCl was observed. The results showed that plant for resistance against salinity increasing of proline, sugar and chlorophyll content in leaves are useful for

  6. Um novo clorofilômetro para estimar os teores de clorofila em folhas do capim Tifton 85 A new chlorophyll meter to estimate chlorophyll contents in leaves of Tifton 85 bermudagrass

    Directory of Open Access Journals (Sweden)

    Élio Barbieri Junior

    2012-12-01

    Full Text Available O propósito deste trabalho foi verificar o desempenho de um novo clorofilometro portátil, em parcelas experimentais vegetadas com o capim-Tifton 85 (Cynodon spp.. Para tal, foi utilizado um experimento de curta duração, em que três doses de N (0,75 e 150kg de N ha-1 foram combinadas com quatro datas de amostragem (8, 16, 24 e 28 dias após um corte de uniformização. As análises foram feitas em lâminas da folha mais nova totalmente expandida. Os teores das clorofilas a, b e a+b foram quantificados espectrofotometricamente após a extração com acetona 80%, enquanto que o clorofilômetro forneceu os correspondentes valores de Índice de Clorofila Falker (ICF. As leituras do aparelho foram sensíveis tanto às doses de N quanto às datas de amostragem. Foram obtidas correlações positivas entre ambos os métodos de quantificação (clorofila a: r=0,646; b: r=0,797; e total: r=0,721, que evidenciaram a utilidade desse novo clorofilometro na determinação indireta dos teores de clorofila foliar no capim-Tifton 85.The purpose of this research was to evaluate the performance of a new portable chlorophyll meter in the indirect determination of chlorophyll contents in Tifton 85 bermudagrass leaves. In a field trial of short duration, three N doses (0, 75 and 150kg ha-1 were combined with four sampling dates (8, 16, 24 e 28 days after a cut for sward uniformity in completely randomized blocks, with treatments arranged in a split-plot design. Analyses were performed in the youngest fully expanded leaf blade. Contents of chlorophylls a, b and total were quantified spectrophotometrically, after extraction with acetone 80%, while chlorophyll meter readings, expressed as Falker Chlorophyll Index (FCI units, provided the same information. Chlorophyll meter readings were sensitive to both N rates and sampling dates. It were obtained significant positive correlations between both methods (chlorophyll a: r=0.646, chlorophyll b: r=0.797 and for total

  7. Interaction of sodium and magnesium on some growth characteristics and chlorophyll content of pistachio in perlite substrate

    Directory of Open Access Journals (Sweden)

    H. Hokmabadi

    2011-07-01

    Full Text Available In calcareous and saline soils, the adverse effect of some ions such as bicarbonate, boron, magnesium, and especially sodium, and the imbalance of nutrients’ concentrations are essential factors which reduce plant growth. A greenhouse experiment was conducted to study the effect of sodium (Na and magnesium (Mg on some growth traits and chlorophyll content of pistachio seedlings (cv. Badami Zarand in perlite. The factorial experiment was carried out as a completely randomized design with four replications. Treatments were three levels of Na (0, 45 and 90 mM NaCl and four levels of Mg (0, 0.5, 1 and 2 mM MgSO4. Modified Hoagland solution was used for irrigation of the pots. The results showed that increasing Na level significantly reduced leaf dry weight, stem height, leaf area and chlorophyll a content. Increasing Mg level up to 0.5 mM (complete Hoagland reduced leaf and root dry weight. When Mg concentration was increased to 2 mM, vigorous reduction in leaf dry weight happened, but it didn’t affect significantly the root dry weight. Application of 2 mM Mg reduced the stem height, leaf number and area, chlorophyll a and total chlorophyll by 18, 25, 19, 42 and 41%, respectively. Interaction of salinity and Mg showed that at zero level of Na and with increasing the Mg concentration, the dry weight of aerial parts and roots, stem height and leaf area were reduced significantly. But when the Na concentration was 90 mM, not only they were not reduced, but also the leaf dry weight was increased more than 60%.

  8. Feeding with aminolevulinic acid increased chlorophyll content in Norway spruce (Picea abies) in the dark

    Czech Academy of Sciences Publication Activity Database

    Pavlovič, A.; Demko, V.; Durchan, Milan; Hudák, J.

    2009-01-01

    Roč. 47, č. 4 (2009), s. 631-634. ISSN 0300-3604 Institutional research plan: CEZ:AV0Z50510513 Keywords : Aminolevulinic acid * Ginkgo biloba * light-independent chlorophyll biosynthesis Subject RIV: CE - Biochemistry Impact factor: 1.072, year: 2009

  9. The effects of different salt concentrations on growth and chlorophyll content of some pumpkin rootstocks

    Directory of Open Access Journals (Sweden)

    Köksal AYDİNŞAKİR

    2015-12-01

    Full Text Available This study was conducted to determine the effects of different salinity levels, (0.7, 4.0, 8.0, 12.0, 16.0 dS m-1 on some physiological parameters of Obez F1, Ferro F1, RS841 F1, which are used as rootstocks in watermelon cultivation. Salty irrigation water was obtained through mixing of NaCl and CaCl2 salt into tap water. When the plants were at the 3-4 leaf stage, different salinity levels were applied. Plants were harvested during the phase of florescence. The study was carried out using split plots in randomized complete block design while rootstocks are main plot, salinity levels are sub-plot with three replications. While the salinity level was increasing, the physiological parameters decreased in each three rootstocks. While the plant height changed between 14.4-107.1 cm, the plant leaf area varied between 152.0-2182.7 cm2. Chlorophyll-a, chlorophyll-b and total carotenoid values decreased as the salinity level increased. Excluding the maximum value obtained from control plot, the highest chlorophyll-a, chlorophyll-b, and total carotenoid values were obtained in Obez variety under 4.0 dS m-1 application with 14.8 mg l-1, 12.8 mg l-1 and 0.28 mg g-1 fw, respectively.

  10. Hole burning study of cyanobacterial Photosystem II complexes differing in the content of small putative chlorophyll-binding proteins

    International Nuclear Information System (INIS)

    This contribution presents low-temperature absorption, both broad-band and site-selective excited fluorescence, and persistent hole burning spectra of Photosystem II complexes from the Photosystem I-lacking strains of the cyanobacterium Synechocystis sp. PCC 6803 differing in the content of small putative chlorophyll-binding proteins (Scps). These proteins are homologous to light-harvesting complex of higher plants and may bind pigments. The excited state lifetimes of the complexes were determined from zero-phonon hole widths extrapolated to zero-burning dose. The area and spectral position of a phonon side-band with respect to the zero-phonon hole provided additional information concerning chlorophyll-protein coupling and the Stokes shift. Decrease of three absorption subbands at (670.0, 672.9, and 675.7 nm) in the Photosystem II isolated from the strain lacking ScpC and ScpD is in agreement with a hypothesis about the role of Scps in the chlorophyll binding. In addition, narrowing of the zero-phonon hole in Photosystem II without both Scps indicates slowering of the excitation energy transfer which may be explained by the absence of a protective excitation energy quenching related to the presence of Scps

  11. Effect Of Heavy Metals Stress On Enzyme Activities And Chlorophyll Content Of Pea (Pisum Sativum) And Tomato Plants

    International Nuclear Information System (INIS)

    The effects of heavy metal stress on the chlorophyll in addition to catalase and peroxidase activities were studied in the leaves and roots of tomato and pea plants. Four groups were studied; the control group and other three groups treated with heavy metals. Group 1HM was treated with 1.0 mg CuSO4/l + 0.2 mg CdSO4/l + 0.1 mg ZnNO3/l every 10 days while in group 5 HM and group 10 HM, the doses were 5 and 10 folds the 1 HM, respectively. Leaves and roots of control and heavy metal-stressed plants were harvested after 10 weeks for chlorophyll determination. The chlorophyll content, especially chlo. b, was significantly decreased with the increase in heavy metals stress in both plants. In leaves of heavy metal-stressed plants, the peroxidase level in different stress levels was increased with increasing stress levels in tomato and pea while catalase was unchanged in leaves of tomato in comparison with the control. The activities of catalase and peroxidase in roots of heavy metal-stressed plants were increased in group 5 HM then decreased in case of group 10 HM. The increase in enzyme activities demonstrated that tomato is more tolerant to heavy metals than pea

  12. Tracking Crop Leaf Area Index and Chlorophyll Content Using RapidEye Data in Northern Ontario, Canada

    Science.gov (United States)

    Shang, J.; Liu, J.; Ma, B.; Zhao, T.; Kovacs, J. M.; Jiao, X.; Dong, T.; Huffman, T.; Geng, X.; Walters, D.

    2014-12-01

    Information on crop phenological state such as flowering, maturing, drying, senescence, and harvesting is essential for crop production surveillance and yield prediction. Earth Observation data provide an important information source for monitoring crop development at various temporal and spatial scales. In particular, the availability of many high-spatial-resolution space sensors offers a powerful tool for precision farming. This study reports the results of a two-year (2012, 2013) study over spring wheat and canola fields using six different vegetation indices derived from the high-resolution (6.5m) RapidEye optical satellite data in northern Ontario, Canada. The study revealed that for both wheat and canola, significant relationships were observed between the ground-derived leaf area index (LAI) and all 6 vegetation indices tested. For spring wheat, the strongest relationship was found between LAI and the Modified Triangular Vegetation Index 2 (MTVI2), with a coefficient of determination (R2) of 0.95. For canola, a R2 of 0.92 was achieved. Strong relationships were also found between all six vegetation indices and the chlorophyll concentration index (CCI) measured in the fields using a CCM-200 device. The strongest correlation exists between CCI and the ratio of Modified the Chlorophyll Absorption Reflected Index (MCARI) and the Optimized Soil Adjusted Vegetation Index (OSAVI), with an R2 of 0.86. It suggests that RapidEye data can be used to track field-scale crop LAI and monitor crop chlorophyll content.

  13. Retrieval of spruce leaf chlorophyll content from airborne image data using continuum removal and radiative transfer

    Czech Academy of Sciences Publication Activity Database

    Malenovský, Z.; Homolová, L.; Zurita-Milla, R.; Lukeš, Petr; Kaplan, Věroslav; Hanuš, Jan; Gastellu-Etchegory, J.P.; Schaepman, M.E.

    2013-01-01

    Roč. 131, APR (2013), s. 85-102. ISSN 0034-4257 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA MŠk(CZ) LM2010007 Institutional support: RVO:67179843 Keywords : Chlorophyll retrieval * Imaging spectroscopy * Continuum removal * Radiative transfer * PROSPECT * DART * Optical indices * Norway spruce * High spatial resolution * AISA Subject RIV: EH - Ecology, Behaviour Impact factor: 4.769, year: 2013

  14. Estimation of single leaf chlorophyll content in sugar beet using machine vision

    OpenAIRE

    MOGHADDAM, Parviz Ahmadi; DERAFSHI, Mohammadali Haddad; SHIRZAD, Vine

    2011-01-01

    Estimating crop nitrogen status accurately during side-dressing operations is essential for effective management of site-specific nitrogen applications. Variable rate technology (VRT) is one of the major operations in precision agriculture to reduce environmental risks and increase fertilizer use efficiency. In the present study, color image analysis was performed to estimate sugar beet leaf chlorophyll status. The experiment was carried out in a phytotron and nitrogen was applied at 6 levels...

  15. Estimation of Spruce Needle-Leaf Chlorophyll Content Based on DART and PARAS Canopy Reflectance Models

    Czech Academy of Sciences Publication Activity Database

    Yáñez-Rausell, L.; Malenovský, Z.; Rautiainen, M.; Clevers, J G P W.; Lukeš, Petr; Hanuš, Jan; Schaepman, M. E.

    2015-01-01

    Roč. 8, č. 4 (2015), s. 1534-1544. ISSN 1939-1404 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : Chlorophyll a plus b estimation * CHRIS-PROBA * coniferous forest * continuum removal * discrete anisotropic radiative transfer model (DART) * needle-leaf * Norway spruce * optical indices * PARAS * PROSPECT * radiative transfer * recollision probability Subject RIV: EH - Ecology, Behaviour Impact factor: 3.026, year: 2014

  16. Effect of Elevated Atmospheric CO2 and Temperature on Leaf Optical Properties and Chlorophyll Content in Acer saccharum (Marsh.)

    Science.gov (United States)

    Carter, Gregory A.; Bahadur, Raj; Norby, Richard J.

    1999-01-01

    Elevated atmospheric CO2 pressure and numerous causes of plant stress often result in decreased leaf chlorophyll contents and thus would be expected to alter leaf optical properties. Hypotheses that elevated carbon dioxide pressure and air temperature would alter leaf optical properties were tested for sugar maple (Acer saccharum Marsh.) in the middle of its fourth growing season under treatment. The saplings had been growing since 1994 in open-top chambers at Oak Ridge, Tennessee under the following treatments: 1) Ambient CO2 pressure and air temperature (control); 2) CO2 pressure approximately 30 Pa above ambient; 3) Air temperatures 3 C above ambient; 4) Elevated CO2 and air temperature. Spectral reflectance, transmittance, and absorptance in the visible spectrum (400-720 nm) did not change significantly (rho = 0.05) in response to any treatment compared with control values. Although reflectance, transmittance, and absorptance at 700 nm correlated strongly with leaf chlorophyll content, chlorophyll content was not altered significantly by the treatments. The lack of treatment effects on pigmentation explained the non-significant change in optical properties in the visible spectrum. Optical properties in the near-infrared (721-850 nm) were similarly unresponsive to treatment with the exception of an increased absorptance in leaves that developed under elevated air temperature alone. This response could not be explained by the data, but might have resulted from effects of air temperature on leaf internal structure. Results indicated no significant potential for detecting leaf optical responses to elevated CO2 or temperature by the remote sensing of reflected radiation in the 400-850 nm spectrum.

  17. Improving Global Models of Remotely Sensed Ocean Chlorophyll Content Using Partial Least Squares and Geographically Weighted Regression

    Science.gov (United States)

    Gholizadeh, H.; Robeson, S. M.

    2015-12-01

    Empirical models have been widely used to estimate global chlorophyll content from remotely sensed data. Here, we focus on the standard NASA empirical models that use blue-green band ratios. These band ratio ocean color (OC) algorithms are in the form of fourth-order polynomials and the parameters of these polynomials (i.e. coefficients) are estimated from the NASA bio-Optical Marine Algorithm Data set (NOMAD). Most of the points in this data set have been sampled from tropical and temperate regions. However, polynomial coefficients obtained from this data set are used to estimate chlorophyll content in all ocean regions with different properties such as sea-surface temperature, salinity, and downwelling/upwelling patterns. Further, the polynomial terms in these models are highly correlated. In sum, the limitations of these empirical models are as follows: 1) the independent variables within the empirical models, in their current form, are correlated (multicollinear), and 2) current algorithms are global approaches and are based on the spatial stationarity assumption, so they are independent of location. Multicollinearity problem is resolved by using partial least squares (PLS). PLS, which transforms the data into a set of independent components, can be considered as a combined form of principal component regression (PCR) and multiple regression. Geographically weighted regression (GWR) is also used to investigate the validity of spatial stationarity assumption. GWR solves a regression model over each sample point by using the observations within its neighbourhood. PLS results show that the empirical method underestimates chlorophyll content in high latitudes, including the Southern Ocean region, when compared to PLS (see Figure 1). Cluster analysis of GWR coefficients also shows that the spatial stationarity assumption in empirical models is not likely a valid assumption.

  18. Chlorophyll and starch assays

    OpenAIRE

    sprotocols

    2015-01-01

    Chlorophyll, starch, and sugar contents are good indicators of growth vigor in plants. To measure the chlorophyll content, we used a modified protocol (1,2). The starch content was determined using iodine staining (3) and enzymatic reactions (4-6).

  19. Effects of Different Nitrogen Forms on the Contents of Chlorophyll and Mineral Elements in Chinese chive Seedlings

    OpenAIRE

    Yongdong Sun; Weirong Luo; Huichao Liu

    2014-01-01

    Chinese chive is an important leafy vegetable, for which nitrogen is vital for growth, development and nutritional quality. In order to study the effects of improved hoagland nutrient solution with different nitrate (NO3-) to ammonium (NH4+) ratios (25:75, 50:50, 75:25 and 100:0) on the contents of chlorophyll and mineral elements (Ca, Fe, Zn, Cu, Mn, Mg and K) for three cultivars, Saisong, Pingjiu No.4 and Pingjiu No.8, under 14 mmol/L nitrogen. An experiment was conducted at experimental pl...

  20. Effect of Cold on Protein, Proline, Phenolic Compounds and Chlorophyll Content of Two Pepper (Capsicum annuum L.) Varieties

    OpenAIRE

    ÜSTÜN, A. Sülün; Esra KOÇ; İŞLEK, Cemil

    2010-01-01

    In this study, quantitative changes of total soluble protein in leaf and stem, apoplastic protein, total phenolic compounds, proline and chlorophyll content were determined in a the cold-susceptible KM-121 (Kahramanmaras- hot) and cold-resistant hybrid pepper Mert (Capsicum annuum L.). The plants were raised in a growth room under a controlled environment of 25± 2 oC and 16 h light / 8 h dark photoperiod. Then, plants exposed to 4oC cold stress for three days and control groups were ke...

  1. Changes in chlorophyll content and fluorescence and fruit yield contributing traits in different genotypes of strawberry (Fragaria x ananassa DUCH.

    Directory of Open Access Journals (Sweden)

    Elżbieta Kaczmarska

    2014-01-01

    Full Text Available Analysis of changes in chlorophyll fluorescence parameters in strawberry leaves was based on a field experiment performed in the years 2009–2010. Ten genotypes including 5 cultivars: ‘Kent’, ‘Teresa’, ‘Senga Sengana’, ‘Chandler’ and the breeding clone 1387 as well as their inbred progeny, were the object of the study. During the experiment the following indicators were evaluated: chlorophyll a and b content in fresh leaf mass as well as fluorescence parameters: minimum (F0 and maximum fluorescence yield (Fm, photochemical efficiency of PS II (Fv/Fm, actual quantum yield of PSII photochemistry (Y, minimum (F0’ and maximum efficiency of fluorescence (Fm’ in the light, coefficient of photochemical (qP and non-photo- chemical (qN fluorescence quenching. In this work, we also examined the effect of repeated inbreeding on strawberry fruit yield and yield components. The analysis of changes of these parameters showed that inbreeding caused a reaction in all tested cultivars. In all inbred progeny, chlorophyll a and b content decreased compared to the cultivars. Generally, the photoche- mical efficiency of photosystem II (Fv/Fm and the parameter ΔF/ Fm’ were not affected by strong inbreeding. In analyzing the values of the coefficients qP and qN, it has been observed that changes in their values depend on the sensitivity of the examined genotypes to self-pollination. The functioning of PS II is the most sensitive indicator of the effect of various factors on plants and is useful, among others, in breeding to select plants with a required genotype. The yield – determining features such as: fruit yield per plant, weight of single fruit, number of fruit per plant and weight of leaves per plant in S3 generation, were lower as compared with parental forms.

  2. Study of water chlorophyl content in the Venice Lagoon through hyperspectral data

    Science.gov (United States)

    Garfagnoli, Francesca; Bizzaro, Beatrice; Moretti, Sandro

    2013-04-01

    In the framework of the HICO Project (http://hico.coas.oregonstate.edu/), a number of radiance and reflectance images of the Venice Lagoon were used to evaluate the possibility of performing quick and reliable mapping of water quality parameters. Sponsored by the Office of Naval Research, the Hyperspectral Imager for the Coastal Ocean (HICO™) is the first spaceborne imaging spectrometer specifically designed to sample the coastal areas, with 128 spectral bands, a 90 m spatial resolution, full spectral coverage (380 to 960 nm sampled at 5.7 nm) and a very high signal-to-noise ratio to resolve the complexity of the coastal ocean. Eutrophication is one of the major causes of water quality deterioration. The concentration of chlorophyll-a found in water can be used to trace the abundance of planktonic algae in rivers, lakes or lagoons. The Venice Lagoon, famous worldwide, represents one of the most fragile and vulnerable ecosystems, which is being constantly threatened by factors of stress, both human and natural, such as erosion, presence of urban and agricultural sources of pollution, stress from fishing, pollution produced by the industrial area of Porto Marghera and by the city of Venice itself, downwash of sediments from the hinterland and eutrophication. Traditional methods of water quality estimation are often time consuming and involve periodical sampling and plenty of laboratory analyses. In this study the possibility of using imaging spectroscopy to rapidly obtain raster-based maps of chlorophyll concentration by comparing the results obtained through five different literature bio-optical models, which permit the retrieval of mathematical relations between the water's spectral properties and physicochemical parameters; pH, dissolved oxygen, turbidity and chlorophyll concentration. Evaluation of performances is achieved by comparing the hyperspectral based maps with maps of kriged concentration values, provided by the Magistrato delle Acque di Venezia (http

  3. Estimation of Norway Spruce leaf chlorophyll content from chris/proba satellite image data

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Malenovský, Z.; Kaplan, Věroslav; Hanuš, Jan; Homolová, L.

    Noordwijk: ESA communication, 2010 - (Lacoste-Francis, H.), s. 1-4 ISBN 978-92-9221-247-6. ISSN 1609-042X. [Hyperspectral worskhop 2010 from chris/proba to PRISMA and EnMAP and beyond. Frascati (IT), 17.03.2010-19.03.2010] R&D Projects: GA MŽP(CZ) SP/2D1/70/08 Institutional research plan: CEZ:AV0Z60870520 Keywords : Norway spruce * chlorophyll * chris/proba Subject RIV: EH - Ecology, Behaviour

  4. In situ hyperspectral data analysis for canopy chlorophyll content estimation of an invasive species spartina alterniflora based on PROSAIL canopy radiative transfer model

    Science.gov (United States)

    Ai, Jinquan; Gao, Wei; Shi, Runhe; Zhang, Chao; Sun, Zhibin; Chen, Wenhui; Liu, Chaoshun; Zeng, Yuyan

    2015-09-01

    Spartina alterniflora is one of the most serious invasive species in the coastal saltmarshes of China. An accurate quantitative estimation of its canopy leaf chlorophyll content is of great importance for monitoring plant physiological state and vegetation productivity. Hyperspectral reflectance data representing a range of canopy chlorophyll content were simulated by using the PROSAIL radiative transfer model at a 1nm sampling interval, which was based on prior knowledge of S.alterniflora. A set of indices was tested for estimating canopy chlorophyll content. Subsequently, validation were performed for testing the performance of indices, based on the PROSAIL model using in situ data measured by a Spectroradiometer with spectral range of 350-2500nm in a late autumn in a sub-tropical estuarine marsh. PROSAIL simulations showed that the most readily available indices were not good to be directly used in canopy chlorophyll estimation of S.alterniflora. The modified Chlorophyll Absorption in Reflectance Index MCARI[705,750] was linear related to the canopy chlorophyll content (R2=0.94) , but did not achieve a satisfactory estimation results with a high RMSE (RMSE=0.95 g.m-2). We optimized the index MCARI[705,750] by introducing a scale conversion coefficient to the formula to solve data units inconsistent, which is between the practical application unit and the unit used in the process of establishing the index, and balance scale transformation through radiative transfer models and examing corresponding canopy reflectance index values. We proposed index Optimized modified Chlorophyll Absorption in Reflectance Index OMCARI[705, 750]. The results showed that the index OMCARI[705, 750] had higher precision of prediction of chlorophyll for S.alterniflora (R2=0.94,RMSE=0.41 g.m-2 ).

  5. The effect of nitrogen fertilization and water stress on stomatal aperture, chlorophyll content and proline accumulation of Napier grass (Pennisetum purpureum Schum)

    OpenAIRE

    Budiman

    2013-01-01

    The objective of the study was to determine the effect of nitrogen fertilization and water stress on the stomatal aperture, chlorophyll and proline accumulation of Napier grass (Pennisetum purpureum Schum.) The effect of water stress and nitrogen fertilizer levels were evaluated within an arrangement of Completely Randomized Design with factorial pattern (2x3). The variables observed were stomatal aperture, total chlorophyll and proline content. The results showed interaction between water s...

  6. Adaptive changes in chlorophyll content and photosynthetic features to low light in Physocarpus amurensis Maxim and Physocarpus opulifolius "Diabolo".

    Science.gov (United States)

    Zhang, Huihui; Zhong, Haixiu; Wang, Jifeng; Sui, Xin; Xu, Nan

    2016-01-01

    The present study aims to investigate the differences in leaf pigment content and the photosynthetic characteristics under natural and low light intensities between the Chinese native Physocarpus amurensis Maxim and the imported Physocarpus opulifolius "Diabolo" from North America. We aim to discuss the responses and the adaptive mechanism of these two cultivars of Physocarpus to a low light environment. The results show that the specific leaf area (SLA) and the chlorophyll content were significantly increased in the leaves of both Physocarpus cultivars in response to a low light intensity, and the SLA and chlorophyll content were higher in the leaves of low light-treated P. opulifolius "Diabolo" compared with the leaves of low light-treated P. amurensis Maxim. Moreover, the content of anthocyanin was markedly reduced in the leaves of P. opulifolius "Diabolo" under low light intensity, which allowed for a greater capacity of photon capture under the low light condition. Under natural light, the photosynthetic carbon assimilation capacity was greater in the leaves of P. amurensis Maxim compared with the leaves of P. opulifolius "Diabolo" that were rich with anthocyanin. However, in response to low light, AQY, P max, LCP and LSP decreased to a lesser extent in the leaves of P. opulifolius "Diabolo" compared with the leaves of P. amurensis Maxim. These results suggest that P. opulifolius "Diabolo" exhibits a greater ability in adaption to low light, and it is probably related to the relatively higher chlorophyll content and the smaller SLA in the leaves of P. opulifolius "Diabolo." In addition, the low light intensity resulted in a reduced photochemical activity of photosystem (PS) II in the leaves of both Physocarpus, as evidenced by increased values of the relative variable fluorescence at point J and point I on the OJIP curve. This result suggests that the electron acceptor in PS II was the major responsive site to the low light stress in the leaves of both

  7. Non-destructive evaluation of chlorophyll content in quinoa and amaranth leaves by simple and multiple regression analysis of RGB image components

    DEFF Research Database (Denmark)

    Riccardi, M.; Mele, G.; Pulvento, C.;

    2014-01-01

    Leaf chlorophyll content provides valuable information about physiological status of plants; it is directly linked to photosynthetic potential and primary production. In vitro assessment by wet chemical extraction is the standard method for leaf chlorophyll determination. This measurement is expe...... foliar chlorophyll content and had a lower amount of noise in the whole range of chlorophyll studied compared with SPAD and other leaf image processing based models when applied to quinoa and amaranth. © 2014 Springer Science+Business Media Dordrecht....... expensive, laborious, and time consuming. Over the years alternative methods, rapid and non-destructive, have been explored. The aim of this work was to evaluate the applicability of a fast and non-invasive field method for estimation of chlorophyll content in quinoa and amaranth leaves based on RGB...... components analysis of digital images acquired with a standard SLR camera. Digital images of leaves from different genotypes of quinoa and amaranth were acquired directly in the field. Mean values of each RGB component were evaluated via image analysis software and correlated to leaf chlorophyll provided by...

  8. Influence of UV-B radiation and Cd2+ on chlorophyll fluorescence, growth and nutrient content in Brassica napus

    International Nuclear Information System (INIS)

    The possible interaction of two stresses, UV-B radiation and cadmium, applied simultaneously, was investigated in Brassica napus L. cv. Paroll with respect to chlorophyll fluorescence, growth and uptake of selected elements. Plants were grown in nutrient solution containing CdCl2, (0, 0.5, 2 or 5 μM) and irradiated with photosynthetically active radiation (PAR, 400–700 nm, 800 μmol m−2 s−1) with or without supplemental ultraviolet-B radiation (UV-B, 280–320 nm, 15 kJ m−2 d−1, weighted irradiance). After 14 d of treatment, the most pronounced effects were found at 2 and 5 μM CdCl2 with and without supplemental UV-B radiation. Exposure to cadmium significantly increased the amount of Cd in both roots and shoots. In addition, increases occurred in the concentration of Fe, Zn, Cu, and P in roots, while K was reduced. In shoots the S content rose significantly both in the presence and absence of UV-B radiation, while significant increases in Mg, Ca, P, Cu, and K occurred only in plants exposed to Cd and UV-B radiation. Manganese decreased significantly under the combined exposure treatment. The rise in S content may have been due to stimulated glutathione and phytochelatin synthesis. Cadmium exposure significantly decreased root dry weight, leaf area, total chlorophyll content, carotenoid content, and the photochemical quantum yield of photosynthesis. As an estimation of energy dissipation processes in photosynthesis, non photochemical quenching (qNPQ) was measured using a pulse amplitude modulated fluorometer. The qNPQ increased with increasing Cd, while the combination of cadmium and UV-B reduced the qNPQ compared to that in plants exposed only to cadmium or UV-B radiation. The chlorophyll a : b ratio showed a reduction with UV-B at no or low Cd concentrations (0 μM, 0.5 μM CdCl2), but not at the higher Cd concentrations used (2 μM, 5 μM CdCl2). Thus in some instances there appeared to be a UV-B and Cd interaction, while in others plant response

  9. Ultrastructure, molecular phylogenetics, and chlorophyll a content of novel cyanobacterial symbionts in temperate sponges.

    Science.gov (United States)

    Erwin, Patrick M; López-Legentil, Susanna; Turon, Xavier

    2012-10-01

    Marine sponges often harbor photosynthetic symbionts that may enhance host metabolism and ecological success, yet little is known about the factors that structure the diversity, specificity, and nature of these relationships. Here, we characterized the cyanobacterial symbionts in two congeneric and sympatric host sponges that exhibit distinct habitat preferences correlated with irradiance: Ircinia fasciculata (higher irradiance) and Ircinia variabilis (lower irradiance). Symbiont composition was similar among hosts and dominated by the sponge-specific cyanobacterium Synechococcus spongiarum. Phylogenetic analyses of 16S-23S rRNA internal transcribed spacer (ITS) gene sequences revealed that Mediterranean Ircinia spp. host a specific, novel symbiont clade ("M") within the S. spongiarum species complex. A second, rare cyanobacterium related to the ascidian symbiont Synechocystis trididemni was observed in low abundance in I. fasciculata and likewise corresponded to a new symbiont clade. Symbiont communities in I. fasciculata exhibited nearly twice the chlorophyll a concentrations of I. variabilis. Further, S. spongiarum clade M symbionts in I. fasciculata exhibited dense intracellular aggregations of glycogen granules, a storage product of photosynthetic carbon assimilation rarely observed in I. variabilis symbionts. In both host sponges, S. spongiarum cells were observed interacting with host archeocytes, although the lower photosynthetic activity of Cyanobacteria in I. variabilis suggests less symbiont-derived nutritional benefit. The observed differences in clade M symbionts among sponge hosts suggest that ambient irradiance conditions dictate symbiont photosynthetic activity and consequently may mediate the nature of host-symbiont relationships. In addition, the plasticity exhibited by clade M symbionts may be an adaptive attribute that allows for flexibility in host-symbiont interactions across the seasonal fluctuations in light and temperature characteristic of

  10. Fourier transform infrared spectroscopy (FTIR) analysis, chlorophyll content and antioxidant properties of native and defatted foliage of green leafy vegetables.

    Science.gov (United States)

    Sravan Kumar, S; Manoj, P; Giridhar, P

    2015-12-01

    FTIR analysis for five selected green leafy vegetables (GLVs) viz., Hibiscus cannabinus L., (kenaf), H. sabdariffa L., (roselle), Basella alba L., (vine spinach), B. rubra L. (malabar spinach) and Rumex vesicarius L., (sorrel) confirmed the presence of free alcohol, intermolecular bonded alcohol, intramolecular bonded alcohol, alkane, aromatic compounds, imine or oxime or ketone or alkene, phenol and amine stretching. The chlorophyll content was higher in native leaves of B. alba (2.96 g/kg) than defatted samples (1.11 g/kg). Total phenolic content (TPC) in H. sabdariffa native methanol extractives is more (17.6 g/kg) than defatted leaves (9.67 g/kg). Native B. rubra methanol extractives exhibited highest total flavonoid content (TFC) (21.59 g/kg), while that of R. vesicarius was lowest (3.21 g/kg). In general, antioxidant activities showed a significant reduction in retention of antioxidants in both native and defatted GLVs samples of ethanol and methanol extractives. Methanol extractives showed significantly stronger antioxidant activity probably due to greater solubility of phenolics and destruction of cellular components. PMID:26604386

  11. Chlorophyll content of spring wheat flag leaves grown under elevated CO2 concentrations and other environmental stresses within the 'ESPACE-wheat' project

    NARCIS (Netherlands)

    Ommen, O.E.; Donnelly, A.; Vanhoutvin, S.; Oijen, van M.; Manderscheid, R.

    1999-01-01

    Spring wheat cv. Minaret was grown in open-top chambers at four sites across Europe. The effect of different treatments (CO2 enrichment, O3 fumigation, drought stress and temperature) on the chlorophyll content of the flag leaf was investigated using the MINOLTA SPAD-502 meter. Under optimum growth

  12. Comparison of web content management system developed by ASP.NET and PHP

    OpenAIRE

    Govek, Matej

    2010-01-01

    The main aim of the diploma thesis is the comparison of the two very popular technologies for the development of web applications. The comparison of PHP and ASP.NET with C# language is done on example of web content management system (WCMS) development. Web site publications are one of the most efficient ways to present our activity to the general public. This diploma work describes the development and performance of web content management system. The comparison of used technology PHP and...

  13. Non-destructive evaluation of chlorophyll content in quinoa and amaranth leaves by simple and multiple regression analysis of RGB image components.

    Science.gov (United States)

    Riccardi, M; Mele, G; Pulvento, C; Lavini, A; d'Andria, R; Jacobsen, S-E

    2014-06-01

    Leaf chlorophyll content provides valuable information about physiological status of plants; it is directly linked to photosynthetic potential and primary production. In vitro assessment by wet chemical extraction is the standard method for leaf chlorophyll determination. This measurement is expensive, laborious, and time consuming. Over the years alternative methods, rapid and non-destructive, have been explored. The aim of this work was to evaluate the applicability of a fast and non-invasive field method for estimation of chlorophyll content in quinoa and amaranth leaves based on RGB components analysis of digital images acquired with a standard SLR camera. Digital images of leaves from different genotypes of quinoa and amaranth were acquired directly in the field. Mean values of each RGB component were evaluated via image analysis software and correlated to leaf chlorophyll provided by standard laboratory procedure. Single and multiple regression models using RGB color components as independent variables have been tested and validated. The performance of the proposed method was compared to that of the widely used non-destructive SPAD method. Sensitivity of the best regression models for different genotypes of quinoa and amaranth was also checked. Color data acquisition of the leaves in the field with a digital camera was quick, more effective, and lower cost than SPAD. The proposed RGB models provided better correlation (highest R (2)) and prediction (lowest RMSEP) of the true value of foliar chlorophyll content and had a lower amount of noise in the whole range of chlorophyll studied compared with SPAD and other leaf image processing based models when applied to quinoa and amaranth. PMID:24442792

  14. Copy Number Variation of Cytokinin Oxidase Gene Tackx4 Associated with Grain Weight and Chlorophyll Content of Flag Leaf in Common Wheat

    Science.gov (United States)

    Chang, Cheng; Lu, Jie; Zhang, Hai-Ping; Ma, Chuan-Xi; Sun, Genlou

    2015-01-01

    As the main pigment in photosynthesis, chlorophyll significantly affects grain filling and grain weight of crop. Cytokinin (CTK) can effectively increase chlorophyll content and chloroplast stability, but it is irreversibly inactivated by cytokinin oxidase (CKX). In this study, therefore, twenty-four pairs of primers were designed to identify variations of wheat CKX (Tackx) genes associated with flag leaf chlorophyll content after anthesis, as well as grain weight in 169 recombinant inbred lines (RIL) derived from Triticum aestivum Jing 411 × Hongmangchun 21. Results indicated variation of Tackx4, identified by primer pair T19-20, was proven to significantly associate with chlorophyll content and grain weight in the RIL population. Here, two Tackx4 patterns were identified: one with two co-segregated fragments (Tackx4-1/Tackx4-2) containing 618 bp and 620 bp in size (as in Jing 411), and another with no PCR product. The two genotypes were designated as genotype-A and genotype-B, respectively. Grain weight and leaf chlorophyll content at 5~15 days after anthesis (DAA) were significantly higher in genotype-A lines than those in genotype-B lines. Mapping analysis indicated Tackx4 was closely linked to Xwmc169 on chromosome 3AL, as well as co-segregated with a major quantitative trait locus (QTL) for both grain weight and chlorophyll content of flag leaf at 5~15 DAA. This QTL explained 8.9~22.3% phenotypic variations of the two traits across four cropping seasons. Among 102 wheat varieties, a third genotype of Tackx4 was found and designated as genotype-C, also having two co-segregated fragments, Tackx4-2 and Tackx4-3 (615bp). The sequences of three fragments, Tackx4-1, Tackx4-2, and Tackx4-3, showed high identity (>98%). Therefore, these fragments could be considered as different copies at Tackx4 locus on chromosome 3AL. The effect of copy number variation (CNV) of Tackx4 was further validated. In general, genotype-A contains both significantly higher grain weight

  15. Growth and content of Spirulina platensis biomass chlorophyll cultivated at different values of light intensity and temperature using different nitrogen sources

    Directory of Open Access Journals (Sweden)

    Eliane Dalva Godoy Danesi

    2011-03-01

    Full Text Available The effects of light intensity and temperature in S. platensis cultivation with potassium nitrate or urea as nitrogen source were investigated, as well as the biomass chlorophyll contents of this cyanobacteria, through the Response Surface Methodology. Experiments were performed at temperatures from 25 to 34.5ºC and light intensities from 15 to 69 µmol photons m-2 s-1, in mineral medium. In cultivations with both sources of nitrogen, KNO3 and urea, statistic evaluation through multiple regression, no interactions of such independent variables were detected in the results of the dependent variables maximum cell concentration, chlorophyll biomass contents, cell and chlorophyll productivities, as well as in the nitrogen-cell conversion factor. In cultivation performed with both sources of nitrogen, it was possible to obtain satisfactory adjustments to relate the dependent variables to the independent variables. The best results were achieved at temperature of 30ºC, at light intensity of 60 µmol photons m-2s-1, for cell growth, with cell productivity of approximately 95 mg L-1 d-1 in cultivations with urea. For the chlorophyll biomass content, the most adequate light intensity was 24 µmol photons m-2 s-1.

  16. Assessment of herbicidal toxicity based on non-destructive measurement of local chlorophyll content in photoautotrophic hairy roots.

    Science.gov (United States)

    Ninomiya, Kazuaki; Oogami, Yoshihiro; Kino-Oka, Masahiro; Taya, Masahito

    2003-01-01

    Changes in local chlorophyll (Chl) content in photoautotrophic hairy roots of pak-bung (Ipomoea aquatica) were evaluated at incident light intensities of I=11 and 22 W/m2 by non-destructive measurement of the pigment based on color image analysis. Upon addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 1-1'-dimethyl-4,4'-bipyridylium dichloride (paraquat) and 2,4-dichlorophenoxyacetic acid (2,4-D) to the medium at the median effective concentrations (0.40, 0.37 and 0.45 micromol/dm3 for DCMU, paraquat and 2,4-D, respectively), the roots showed different Chl pigmentation responses when the Chl content was measured at longitudinal lengths of l0=2.5 mm (Chl accumulation position) and l(0)=35 mm (Chl saturation position) under light irradiation. Chl accumulation index (beta) and Chl degradation index (gamma) were determined from the changes in Chl content at l0=2.5 and 35 mm, respectively, during the cultures for 96 h: beta=0% (DCMU), 93.6% (paraquat) and 93.8% (2,4-D), and gamma=98.4% (DCMU), 282% (paraquat) and 86.5% (2,4-D) at I=22 W/m2. Moreover, the bioassay system with the hairy roots was applied to the evaluation of a model sample of field water. The values of beta and gamma for the field water were determined, respectively, to be 105% and 217% at I=22 W/m2, from which the field water tested was judged to be a "paraquat-like" toxicant against the roots. PMID:16233403

  17. Development of FT-NIR Models for the Simultaneous Estimation of Chlorophyll and Nitrogen Content in Fresh Apple (Malus Domestica Leaves

    Directory of Open Access Journals (Sweden)

    Elena Tamburini

    2015-01-01

    Full Text Available Agricultural practices determine the level of food production and, to great extent, the state of the global environment. During the last decades, the indiscriminate recourse to fertilizers as well as the nitrogen losses from land application have been recognized as serious issues of modern agriculture, globally contributing to nitrate pollution. The development of a reliable Near-Infra-Red Spectroscopy (NIRS-based method, for the simultaneous monitoring of nitrogen and chlorophyll in fresh apple (Malus domestica leaves, was investigated on a set of 133 samples, with the aim of estimating the nutritional and physiological status of trees, in real time, cheaply and non-destructively. By means of a FT (Fourier Transform-NIR instrument, Partial Least Squares (PLS regression models were developed, spanning a concentration range of 0.577%–0.817% for the total Kjeldahl nitrogen (TKN content (R2 = 0.983; SEC = 0.012; SEP = 0.028, and of 1.534–2.372 mg/g for the total chlorophyll content (R2 = 0.941; SEC = 0.132; SEP = 0.162. Chlorophyll-a and chlorophyll-b contents were also evaluated (R2 = 0.913; SEC = 0.076; SEP = 0.101 and R2 = 0.899; SEC = 0.059; SEP = 0.101, respectively. All calibration models were validated by means of 47 independent samples. The NIR approach allows a rapid evaluation of the nitrogen and chlorophyll contents, and may represent a useful tool for determining nutritional and physiological status of plants, in order to allow a correction of nutrition programs during the season.

  18. Estimation of leaf chlorophyll content in winter wheat using variable importance for projection (VIP) with hyperspectral data

    Science.gov (United States)

    He, Peng; Xu, Xingang; Zhang, Baolei; Li, Zhenhai; Feng, Haikuan; Yang, Guijun; Zhang, Yongfeng

    2015-10-01

    Accurate estimation of leaf chlorophyll content (LCC) has great significance in study of the winter wheat, which is important for indicating nutrition status and photosynthetic. Selecting the closed related variable is the key to LCC monitoring. The variable importance for projection (VIP), applied to little samples and strong correlation data, is one of variable selection methods. In this study, VIP was used to select spectral variables, which includes reflectance spectra, first derivative spectra, vegetation indices and absorption or reflectance position features. The grey relational analysis (GRA) was used as a comparison. The results showed that (1) the VIP technology could be used to variable selection and had a strong correlation. (2) Reflectance spectra with the VIP method displayed the best accuracy, with R2 and RMSE of 0.42 and 0.663mg/g, respectively. (3) Vegetation indices using GRA had higher estimation than VIP method, with R2 and RMSE of 0.52 and 0.607 mg/g, respectively. (4) The VIP had more superiority and higher accuracy than the GRA in all kinds of hyperspectral features except vegetation indices. Therefore, the VIP technology could be used to the estimation of LCC and had a relatively good accuracy.

  19. Effects of external phosphorus on the cell ultrastructure and the chlorophyll content of maize under cadmium and zinc stress

    International Nuclear Information System (INIS)

    Using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis, it was found that the ultrastructure of chloroplasts were changed, the shape of the chloroplasts altered and the numbers of grana that were asymmetrical increased; the numbers of grana and thylakoids decreased under the stress of Cd and Zn. The results indicated that the complex pollution involving Cd and Zn resulted in the membrane system of chloroplasts being damaged. When external phosphorus was applied, the numbers of damaged chloroplasts were significantly reduced and the nucleoli were better formed than those that did not receive phosphorus treatment. Moreover, many phosphate deposits were found in the vacuoles and on the surface of the roots, which were formed by phosphorus complexing with Cd (K sp = 2.53 x 10-33) and Zn (K sp = 9.00 x 10-33), respectively. Treatment with phosphorus conduced an increased chlorophyll content in plants compared with those that did not receive external phosphorus. - External P could decrease the bioavailability of Cd and Zn

  20. Effect of Funneliformis mosseae on growth, mineral nutrition, biochemical indexes and chlorophyll content of Ziziphus spina-christi seedlings at different salinities

    Directory of Open Access Journals (Sweden)

    Mirzaei J

    2015-12-01

    Full Text Available Vast area of the land around the world is saline. Knowledge of plant behavior and their interaction with mychorrizal fungi in saline areas may help seedling establishment in such environments. This study aimed to determine the effects of the inoculation of the fungus Funneliformis mosseae (FM on Ziziphus spina-christi (Rhamnaceae plants grown under salt stress. Mycorrhizal and non-mycorrhizal seedlings were exposed to different levels of NaCl in the soil (0, 50, 100, and 150 mM. The following parameters were measured in both inoculated and non-inoculated plants: root colonization rate, seedling height, root diameter, root and shoot dry weights, chlorophyll a and b, total nitrogen (N, phosphorus (P, potassium (K and sodium (Na+ content, proline accumulation in roots and leaves, superoxide dismutase (SOD, peroxidase (POD and catalase (CAT activities. The results showed that soil salinity hampered the root colonization by the fungus, and decreased basal diameter, seedling height, root and shoot dry weights, as well as some nutrients and chlorophyll a concentration, while increased leaves and roots Na+, SOD and POD activity, proline accumulation, as well as CAT activity in the roots. Contrastingly, no significant effect of soil salinity were detected on K and CAT of leaves, root N, and chlorophyll b. Inoculated plants had higher basal diameter, leaves and roots P, root and shoot dry weights, chlorophyll a and lower SOD content, proline accumulation in leaves and Na+, as compared with non-inoculated plants. Seedling height, root N, CAT and POD content, and chlorophyll b were not affected by inoculation with FM. These results demonstrated that FM inoculation is a promising method for improving the growth of Z. spina-christi seedlings under salt stress.

  1. Growth, essential oil content, and content of coumarin in young plants of guaco (Mikania glomerata Sprengel cultivated under colored nets

    Directory of Open Access Journals (Sweden)

    Girlene Santos Souza

    2011-09-01

    Full Text Available Mikania glomerata Sprengel is a medicinal plant widely used in folk medicine, mainly to treat respiratory disorders, which acts by dilating the bronchi, being coumarin one of the substances associated with this effect. Therefore, understanding the physiological behavior of this species and its responses to the environmental conditions is necessary to improve the cultivation methods. In this context, the aim of this work was to evaluate the effect of light spectrum control on growth, the essential oil content, and the content of coumarin in Mikania glomerata Sprengel. Plants were grown for four months under nets with 50% shading in gray, red, blue, and exposed to full sunlight (0%. The essential oil was extracted from fresh leaves through hydrodistillation in a modified Clevenger apparatus. The identification and quantification of coumarin were performed through high performance liquid chromatography (HPLC. The results showed the blue fabric allowed an increase in total dry matter accumulation and leaf area, as plants under red shading presented higher dry matter allocation to the roots. The smallest quantity of dry leaves was observed in plants grown under full sun exposure. Changes were not observed, however, in leaf weight ratio and in root/shoot proportion. The essential oil content of plants grown under blue net was 0.14%, which corresponded to an increase of 142% over the level found in plants grown under full sun exposure, as the coumarin content was not influenced by the net color. These results show that light can be modulated during cultivation, in order to obtain desirable morphological characteristics and maximize the production of active principles in this species.

  2. Studying dream content using the archive and search engine on DreamBank.net.

    Science.gov (United States)

    Domhoff, G William; Schneider, Adam

    2008-12-01

    This paper shows how the dream archive and search engine on DreamBank.net, a Web site containing over 22,000 dream reports, can be used to generate new findings on dream content, some of which raise interesting questions about the relationship between dreaming and various forms of waking thought. It begins with studies that draw dream reports from DreamBank.net for studies of social networks in dreams, and then demonstrates the usefulness of the search engine by employing word strings relating to religious and sexual elements. Examples from two lengthy individual dream series are used to show how the dreams of one person can be studied for characters, activities, and emotions. A final example shows that accurate inferences about a person's religious beliefs can be made on the basis of reading through dreams retrieved with a few keywords. The overall findings are similar to those in studies using traditional forms of content analysis. PMID:18682331

  3. "Net Neutrality," Non-Discrimination and Digital Distribution of Content Through the Internet

    OpenAIRE

    Nicholas Economides

    2007-01-01

    The vast majority of US residential consumers face a monopoly or duopoly in broadband Internet access. Up to now, the Internet was characterized by a regime of "net neutrality" where there was no discrimination in the price of a transmitted information packet based on the identities of either the transmitter or the receiver or based on the application or type of content that it contained. The providers of DSL or cable modem access in the United States, taking advantage of a recent regulatory ...

  4. Effect of single varied doses of UV-C radiation on photosynthesis, traspiration and chlorophyll content in the leaves of two varieties of faba bean and pea

    International Nuclear Information System (INIS)

    The effect of single, varied (75, 120 and 165 min) UV-C radiation on photosynthesis and transpiration in leaves of two morphotypes of faba bean and pea was determined in a pot experiment. The SPAD leaf greenness index, which characterises the a and b chlorophyll contents (as well as changes in its content caused by radiation) were analysed. The experimental results indicated that the intensity of photosynthesis and transpiration in faba bean leaves was higher in the plants treated with the UV-C radiation. In addition, the intensity of photosynthesis and the chlorophyll content were higher in the Neptun variety than in the self-terminating faba bean variety. The Rola pea variety plants showed a significant decrease in photsynthesis intensity under radiation in the 3rd leaf phase and a slight decrease in later developmental phases. Moreover, transpiration was found to decrease at the beginning of the vegetation. In the case of the Ramrod variety, rather ambiguous results were obtained. The chlorophyll content in both pea varieties was high in the 3rd proper leaf phase and in the Rola plants it increased with increasing radiation doses in the stem extension phase

  5. Hill Reaction, Photosynthesis and Chlorophyll Content in Non-Sugar-Producing (Turnip, Brassica rapa L.) and Sugar-Producing (Sugar beet, Beta vulgaris L.) Root Crop Plants

    OpenAIRE

    Siddiqui, Manzer H.; Khan, M. Masroor A.; Khan, M. Nasir; Mohammad, Firoz; Naeem, M.

    2006-01-01

    A pot experiment was conducted at the Botany Department, A.M.U., Aligarh, on 2 root crop plants, viz. turnip (Brassica rapa L.), non-sugar-producing and sugar beet (Beta vulgaris L.), sugar-producing, to compare their physiological activity (Hill activity, photosynthesis and chlorophyll content). The seeds of each plant were sown in 20 pots (80% soil + 20% FYM) separately. Two samplings were done at 125 and 140 days (after sowing). Hill activity was measured spectrophotometrically using DCPI...

  6. Effects of Light Intensity on Development and Chlorophyll Content in the Arabidopsis Mutant Plants with Defects in Photosynthesis

    OpenAIRE

    E.Yu. Garnik; D.V. Deeva; V.I. Belkov; V.I. Tarasenko; Yu.M. Konstantinov

    2015-01-01

    The developmental stages and adaptability to different light intensity (150 µmol*m-2*s-1 and 100 µmol*m-2*s-1) in Arabidopsis mutant lines with defects of photosynthetic apparatus were analyzed. Plant development in the mutant lines depended on the light intensity to varying degrees. Lines ch1-1 (lack of the chlorophyllide a oxygenase) and rtn16 (decreased chlorophyll a and b amounts) were the most susceptible to the light decrease. No one of the investigated lines demonstrated chlorophyll a/...

  7. The effect of ionizing radiation on the content of chlorophylls and carotenoids in wheat seedlings in the presence of an iron complex

    International Nuclear Information System (INIS)

    The study of changes in the content of pigments and processes that take place in pigment-protein complexes of chloroplast membranes after irradiation with the use of radio-protectors are devoted to a a small number of works. Objective of our research was to study the influence of gamma irradiation on the content of chlorophylls and carotenoids in wheat seedlings by using a complex of iron with yuglon to determine its radioprotective properties. The data indicate that the iron yuglonate reduces damaging effects of radiation, and supports the normal course of pigment biosynthesis

  8. Joint leaf chlorophyll content and leaf area index retrieval from Landsat data using a regularized model inversion system (REGFLEC)

    KAUST Repository

    Houborg, Rasmus

    2015-03-01

    Leaf area index (LAI) and leaf chlorophyll content (Chll) represent key biophysical and biochemical controls on water, energy and carbon exchange processes in the terrestrial biosphere. In combination, LAI and Chll provide critical information on vegetation density, vitality and photosynthetic potentials. However, simultaneous retrieval of LAI and Chll from space observations is extremely challenging. Regularization strategies are required to increase the robustness and accuracy of retrieved properties and enable more reliable separation of soil, leaf and canopy parameters. To address these challenges, the REGularized canopy reFLECtance model (REGFLEC) inversion system was refined to incorporate enhanced techniques for exploiting ancillary LAI and temporal information derived from multiple satellite scenes. In this current analysis, REGFLEC is applied to a time-series of Landsat data.A novel aspect of the REGFLEC approach is the fact that no site-specific data are required to calibrate the model, which may be run in a largely automated fashion using information extracted entirely from image-based and other widely available datasets. Validation results, based upon in-situ LAI and Chll observations collected over maize and soybean fields in central Nebraska for the period 2001-2005, demonstrate Chll retrieval with a relative root-mean-square-deviation (RMSD) on the order of 19% (RMSD=8.42μgcm-2). While Chll retrievals were clearly influenced by the version of the leaf optical properties model used (PROSPECT), the application of spatio-temporal regularization constraints was shown to be critical for estimating Chll with sufficient accuracy. REGFLEC also reproduced the dynamics of in-situ measured LAI well (r2 =0.85), but estimates were biased low, particularly over maize (LAI was underestimated by ~36 %). This disparity may be attributed to differences between effective and true LAI caused by significant foliage clumping not being properly accounted for in the canopy

  9. Effect of Zinc and Bio Fertilizers on Antioxidant Enzymes Activity, Chlorophyll Content, Soluble Sugars and Proline in Triticale Under Salinity Condition

    Directory of Open Access Journals (Sweden)

    Younes KHEIRIZADEH AROUGH

    2016-06-01

    Full Text Available In order to study the effects of bio fertilizers and zinc fertilizer on antioxidant enzymes activity, chlorophyll content, soluble sugars and proline in triticale under salinity condition, a factorial experiment was conducted based on randomized complete block design with three replications under greenhouse condition. Experiment factors were included salinity in four levels [no-salt (control or S0, salinity 20 (S1, 40 (S2 and 60 (S3 mM NaCl equivalent of 1.85, 3.7 and 5.55 dS m−1 respectively], four bio fertilizers levels (no bio fertilizer (F0, application of mycorrhiza (F1, PGPR (F2, both application PGPR and mycorrhiza (F3 and three nano zinc oxide levels (without nano zinc oxide as control (Zn0, application of 0.4 (Zn1 and 0.8 (Zn2 g lit-1. Results showed that salinity severe stress (60 mM decreased chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and grain yield of triticale, whereas soluble sugars and proline content, the activities of Catalase (CAT, Peroxidase (POD Polyphenol Oxidase (PPO enzymes increased. Results showed that both application of bio fertilizer and 0.8 g lit-1 nano zinc oxide (F3Zn2 increased about 39% from grain yield in comparison with F0Zn0 under the highest salinity level. Based on the results, it was concluded that bio fertilizers and nano zinc oxide application can be recommended for profitable triticale production under salinity condition.

  10. Effect of Zinc and Bio Fertilizers on Antioxidant Enzymes Activity, Chlorophyll Content, Soluble Sugars and Proline in Triticale Under Salinity Condition

    OpenAIRE

    Younes KHEIRIZADEH AROUGH; Raouf SEYED SHARIFI; Mohammad SEDGHI; Morteza BARMAKI

    2016-01-01

    In order to study the effects of bio fertilizers and zinc fertilizer on antioxidant enzymes activity, chlorophyll content, soluble sugars and proline in triticale under salinity condition, a factorial experiment was conducted based on randomized complete block design with three replications under greenhouse condition. Experiment factors were included salinity in four levels [no-salt (control or S0), salinity 20 (S1), 40 (S2) and 60 (S3) mM NaCl) equivalent of 1.85, 3.7 and 5.55 dS m−1 respect...

  11. Learning Content Recommendation for Visual Basic.Net Programming Language based on Ontology

    Directory of Open Access Journals (Sweden)

    Saman Shishehchi

    2011-01-01

    Full Text Available Nowadays, the quality of learning and the expansion of education technology, motivate the researchers to work on learning area more than before. Problem statement: With the rapid advance of learning contents on the web and also the variety of learning books, finding suitable ones has become a very difficult and complicated task for learners. Approach: This study aims to propose a learning system includes the semantic recommender system. Students can employ this application to learn learning content at anywhere. This system works based on the learner’s knowledge level and also the learner’s request that system asks from the learner at the beginning. Learner will be able to find and learn the right learning materials to reach their request. Finally, all changes about learner will store in the learner model in the ontology. The proposed architecture comprises some subsystems and components. One of the most important of subsystems is a knowledge based system, which covers the ontology which called VBnet ontology. This ontology consists of three parts; LearnerModel, Domain Concept and Learning Material. Moreover, we define two other subsystems; Learner performance evaluation, recommendation system and some modules; Availability checker, Knowledge evaluator, Exam generator, Request analyzer and user interface. Results: Considering to scope of research we develop the ontology for Visual Basic.Net programming language and describe all available classes and subclasses step by step. Also we create some query by SPARQL and show the information retrival from VB ontology. Conclusion: This system can help to student to learn materials of Visual Basic.Net with the good quality without the place dependency.

  12. Effects of non-carbonaceous meteoritic extracts on the germination, growth and chlorophyll content of edible plants

    Science.gov (United States)

    Marcano, Vicente; Matheus, Paula; Cedeño, Cesyen; Falcon, Nelson; Palacios-Prü, Ernesto

    2005-10-01

    We have conducted an investigation on the effects that the extracts of a non-carbonaceous meteorite could have on the germination and growth of plants and the ability of non-carbonaceous meteoritic resource to serve as nutrient source for young plants of edible types. Selected plants were two dicotyledons ( Lycopersicon esculentum and Daucus carota) and one monocotyledon ( Zea mays). Solution cultures were developed using seeds, seedlings and seed-embryos. Meteoritic powder was obtained from the Vigirima mesosiderite, which was analyzed by X-ray diffraction and atomic absorption spectrometry (AAS). Results showed that extracts having variable concentrations of meteoritic matter favored an earlier germination in some plant species but the increase of the concentrations produced a decreased germination. However, total germination rate was higher in the presence of meteoritic extracts than in the presence of controls in the all species. A high metabolic yield in the protein synthesis was seen in dicotyledons utilizing Type-A and B extracts having concentrations of 4.16-8.33×10 3 mg l -1. Phaeophytinization index and chlorophyll a/b ratio, suggesting a negative effect of the heavy metals or acidic ions over the photosynthetic activity when extracts having high meteoritic concentrations were utilized. However, a higher chlorophyll (a) production in comparison to that of chlorophyll (b) was seen in extracts (Type-A and -B) with low concentrations of meteoritic matter. On the other hand, Z. mays seed-embryos growing in extracts (Type-D) having 3.53×10 4 mg l -1 of meteoritic matter showed a protein production (9.81×10 -2 mg protein mg wet wt -1) higher than that observed in seed-embryos coming from extracts having lower concentrations. However, in Murashige medium, the seed-embryos exhibited a enhanced growth and a relatively higher protein production (10.3×10 -2 mg protein mg wet wt. -1). Further, chlorophyll (a+b) synthesis was higher in Murashige medium than in

  13. Effects of narcissism, leisure boredom, and gratifications sought on user-generated content among net-generation users

    OpenAIRE

    Damon, Chi-Him Poona; Louis, Wing-Chi Leung

    2011-01-01

    This research identifies the gratifications sought by the net-generation when producing user-generated content (UGC) on the internet. Members of the Net-generation want to vent negative feelings, show affection to their frieds and relatives, be involved in others' lives, and fulfill their need to be recognized. These gratifications were all found to be significantly associated with the users' various levels of participation in UGC (e.g., Facebook, YouTube, blogs, online forums, etc.) What's m...

  14. Effect of pre-harvest foliar application of citric acid and malic acid on chlorophyll content and post-harvest vase life of Lilium cv. Brunello

    Directory of Open Access Journals (Sweden)

    Nafiseh eDarandeh

    2012-01-01

    Full Text Available Preharvest use of citric acid is a novel method in vase life extension of cut flowers, which is reported on tuberose earlier and confirmed here on lilium. In this research citric acid (0, 0.075, 0.15 percent v/v and malic acid (0, 0.075, 0.15 percent v/v were used together two times during growth period of lilium plants in a randomized factorial design with three replications. The results point out that 0.15% citric acid had increased vase life from 13.1 to 14 days (α=0.05. The interesting finding was the effect of citric acid on bulbil weight, which was decreased from 8.6 gr to 2.9 gr in 0.15% citric acid per cut flower. Malic acid while having no effect on pre-mentioned traits surprisingly increased the chlorophyll content significantly. The interaction effect between citric acid and malic acid on vase life and chlorophyll content proved significant and was evident in results both as antagonistic and synergistic in various traits. In mean comparison of factor-levels, the effect of citric acid on vase-life extension was more prominent increasing it from 11.8 to 14.3 days in treatment with 0.15% citric acid and without malic acid compared to control treatment.

  15. Irrigation of three wetland species and a hyperaccumlating fern with arsenic-laden solutions: observations of growth, arsenic uptake, nutrient status, and chlorophyll content.

    Science.gov (United States)

    Rofkar, Jordan R; Dwyer, Daryl F

    2013-01-01

    Engineered wetlands can be an integral part of a treatment strategy for remediating arsenic-contaminated wastewater, wherein, As is removed by adsorption to soil particles, chemical transformation, precipitation, or accumulation by plants. The remediation process could be optimized by choosing plant species that take up As throughout the seasonal growing period. This report details experiments that utilize wetland plant species native to Ohio (Carex stricta, Pycnanthemum virginianum, and Spartina pectinata) that exhibit seasonally related maximal growth rates, plus one hyperaccumulating fern (Pteris vittata) that was used to compare arsenic tolerance. All plants were irrigated with control or As-laden nutrient solutions (either 0, 1.5, or 25 mg As L(-1)) for 52 d. Biomass, nutrient content, and chlorophyll content were compared between plants treated and control plants (n = 5). At the higher concentration of arsenic (25 mg L(-1)), plant biomass, leaf area, and total chlorophyll were all lower than values in control plants. A tolerance index, based on total plant biomass at the end of the experiment, indicated C. stricta (0.99) and S. pectinata (0.84) were more tolerant than the other plant species when irrigated with 1.5 mg As L(-1). These plant species can be considered as candidates for engineered wetlands. PMID:23819297

  16. Effect of Pre-Harvest Foliar Application of Citric Acid and Malic Acid on Chlorophyll Content and Post-Harvest Vase Life of Lilium cv. Brunello.

    Science.gov (United States)

    Darandeh, Nafiseh; Hadavi, Ebrahim

    2011-01-01

    Citric acid is a regular ingredient in many vase solution formulations but pre-harvest use of citric acid is a novel method in vase life extension of cut flowers, which is reported on tuberose earlier. In order to verify previous result, and check for possible substitution of citric acid by malic acid, the current research was designed. Citric acid (0, 0.075, 0.15% w/v) and malic acid (0, 0.075, 0.15% w/v) were used in a factorial design with three replications. Foliar sprays were applied two times during growth period of Lilium plants. The results point out that 0.15% citric acid alone had increased vase life from 11.8 in control treatment to 14 days (α < 0.05). The interesting finding was the effect of citric acid on bulbil weight, which was decreased from 9 g in control to 1.5 g in treatment containing combination of 0.075% citric acid and 0.075% malic acid. Malic acid while having no direct effect on pre-mentioned traits surprisingly increased the chlorophyll content significantly. The interaction effect between citric acid and malic acid on vase life and chlorophyll content proved significant and was evident in results, both as antagonistic and synergistic in various traits. PMID:22639626

  17. Effects of gamma radiation on chlorophyll content of Cladonia verticillaris (Raddi) Fr. (lichen) collected in different environments

    International Nuclear Information System (INIS)

    Lichens are formed by symbiosis between a fungus (mycobiont) and an alga (photobiont, chloroficeae and or cyanobacteria). The radiosensitivity in lichens is not in proportion to the symbiotic organisms, and the algae layer is more radiosensitive than the fungi. Thus, in order check to algae radiosensitivity, sought to quantify the levels of chlorophyll from C. verticillaris samples with different doses of gamma radiation, since the amount of this pigment is closely related to the percentage of living algal cells. Lichen samples were collected in Saloa-PE and Alhandra- PE, sites that have similar physiognomic characteristics, but with different altitudes. C. verticillaris samples (12 g) of both sampling sites were subjected to gamma irradiator (Co60 - irradiator, Gammacell 200 Excel, dose rates 7.795 kGy) at 0, 10, 50, 100, 500, 1.000, 5.000 and 10.000 Gy. Lichens samples were collected (1.5 g) and stored separately for further analysis. The results indicated that the total production of chlorophyll in all samples exposed to gamma radiation was lower than non-irradiated samples, demonstrating that way that gamma radiation causes likely to damage/changes in physiological characteristics C. verticillaris. (author)

  18. Effects of gamma radiation on chlorophyll content of Cladonia verticillaris (Raddi) Fr. (lichen) collected in different environments

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Helena P. de B.; Martins, Monica C.B.; Pereira, Eugenia C.; Barbosa, Clarissa R.; Silva, Nicacio; Franca, Andre Luiz Teixeira de; Colaco, Waldeciro, E-mail: barrosleny@hotmail.com, E-mail: monicabarmartins@hotmail.com, E-mail: verticillaris@gmail.com, E-mail: lissa_fer@hotmail.com, E-mail: nhsilva@uol.com.br, E-mail: wcolaco@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Maciel, Leonardo N. de Q., E-mail: lenoquema@yahoo.com.br [Instituto Federal de Educacao Ciencia e Tecnologia de Pernambuco (IFPE), Vitoria de Santo Antao, PE (Brazil)

    2013-07-01

    Lichens are formed by symbiosis between a fungus (mycobiont) and an alga (photobiont, chloroficeae and or cyanobacteria). The radiosensitivity in lichens is not in proportion to the symbiotic organisms, and the algae layer is more radiosensitive than the fungi. Thus, in order check to algae radiosensitivity, sought to quantify the levels of chlorophyll from C. verticillaris samples with different doses of gamma radiation, since the amount of this pigment is closely related to the percentage of living algal cells. Lichen samples were collected in Saloa-PE and Alhandra- PE, sites that have similar physiognomic characteristics, but with different altitudes. C. verticillaris samples (12 g) of both sampling sites were subjected to gamma irradiator (Co{sup 60} - irradiator, Gammacell 200 Excel, dose rates 7.795 kGy) at 0, 10, 50, 100, 500, 1.000, 5.000 and 10.000 Gy. Lichens samples were collected (1.5 g) and stored separately for further analysis. The results indicated that the total production of chlorophyll in all samples exposed to gamma radiation was lower than non-irradiated samples, demonstrating that way that gamma radiation causes likely to damage/changes in physiological characteristics C. verticillaris. (author)

  19. 基于颜色参数变化的青花菜叶绿素含量预测模型%A Prediction Model for Chlorophyll Content in Post-harvest Broccoli Based on Color Parameter Changes

    Institute of Scientific and Technical Information of China (English)

    许凤; 杨震峰; 裴娇艳; 郑永华

    2011-01-01

    为研究青花菜贮藏期间叶绿素含量和颜色变化的关系,通过不同温度贮藏实验建立基于颜色参数-a/b值的叶绿素含量预测模型。将青花菜贮藏在273、278、283、293、303K条件下,测定花蕾-a/b值和叶绿素含量的变化。基于Arrhenius动力学方程分别建立青花菜-a/b值、叶绿素含量与贮藏时间和温度之间的动力学模型,再根据-a/b值与叶绿素含量变化的线性关系,进一步建立基于-a/b值的叶绿素含量预测模型。在275、280、285、295、305K贮藏温度条件下对基于-a/b值的叶绿素含量预测模型进行验证,%In order to explore the relationship between chlorophyll content and color change of post-harvest broccoli during storage,a prediction model for chlorophyll content was established based on color parameter changes.Freshly harvested broccoli was stored at different temperatures(273,278,283,293 K and 303 K),and the color parameter-a/b value and chlorophyll content of broccoli were determined.Kinetic models of-a/b value and chlorophyll content with respect to storage time and temperature were established on the basis of Arrhenius equation.In addition,a prediction model for chlorophyll content based on-a/b value was further developed according to the linear relationship between chlorophyll content and-a/b value.Moreover,the prediction model for chlorophyll content based on-a/b value was validated using broccoli stored at 275,280,285,295 K and 305 K with a relative prediction error of 4.31%.The chlorophyll content of broccoli can be accurately predicted at the storage temperature from 273 K to 305 K using this prediction model.Therefore,the prediction model is acceptable for applying the color parameter-a/b to evaluate broccoli quality.

  20. Acetyl salicylic acid and 24-epibrassinolide attenuate decline in photosynthesis, chlorophyll contents and membrane thermo- stability in tomato (lycopersicon esculentum mill.) under heat stress

    International Nuclear Information System (INIS)

    The effect of exogenous application of varying levels of 24-epibrassinolide (0.75, 1.5 and 3 micro M) and acetyl salicylic acid (0.25, 0.75 and 1.25 micro M) for induction of heat tolerance in terms of their effect on photosynthesis, chlorophyll content, membrane integrity and survival in four weeks old tomato (cultivar: Mei Jie Lo) seedlings under high temperature stress (46 degree C/4 h daily) for 21 days was investigated. The daily heat stress treatment had deleterious effects on seedlings but chemical treatments significantly reduced the magnitude of losses to different extents. 24-epibrassinolide (3 micro M) was over all the best treatment to improve survival (86.11%), photosynthesis (39.4%) and chlorophyll contents (26.12%) accompanied with initiation of flower buds and improved vegetative growth. Whereas acetyl salicylic acid (1.25 mM) best improved photosynthetic activity (40.6%) as compared to the untreated heat stressed control seedlings. Moreover, 3 micro M 24-epibrassinolide and 0.75 micro M acetyl salicylic acid reduced cell membrane injury to 8.3 and 6.9% respectively as compared with 22.4% in heat stressed control seedlings. However lower doses of acetyl salicylic acid (0.25 and 0.75 micro M) had slight (5.6 and 12.8%) inhibition effect on the photosynthesis than the heat stressed controls. Overall both acetyl salicylic acid and 24-epibrassinolide up regulated basal heat tolerance in tomato seedlings and studied concentrations demonstrated signature affect upon different parameters. Thus both chemical agents can be potential candidates for further investigations for exogenous application aiming at extension of tomato growth season in summer. (author)

  1. Photosynthetic activity, chlorophyll-fluorescence parameters and pigment content of differently damaged spruces at the Schoellkopf (Northern Black Forest). Photosyntheseaktivitaet, Chlorophyllfluoreszenzparameter und Pigmentgehalt unterschiedlich geschaedigter Fichten am Schoellkopf (Nordschwarzwald)

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenthaler, H.K.; Rinderle, U.; Burkart, S.; Hak, R. (Karlsruhe Univ. (T.H.) (Germany, F.R.). Botanisches Inst. 2)

    1990-04-01

    At the new PEF-site Schoellkopf (840 m above see level) various physiological parameters were determined from one relatively healthy (tree No. 13) and two differently damaged spruces (tree No. 17 and 2): The netto assimilation rate P{sub N} (on a needle area and a chlorophyl basis), respiration, transpiration and stomata conductivity (gH{sub 2}O), the content of photosynthetic pigments (chlorophyll a+b, carotenoids x+c), the pigment ratios (a/b; a+b/x+c) and various parameters of the in vivo chlorophyll fluorescence (Rfd-values at 690 and 730 nm, the fluorescence ratio F690/F730; quenching-coefficients qP and qNP, the ratio Fm/Fo and Fv/Fm). Stress and damage are preferentially indicated by lower values of the chlorophyll content, the pigment ratio a+b/x+c, the assimilation rate P{sub N} and the hight of the saturation pulse spikes (g-h) as well as increased values of the coefficient qNP and the fluorescence ratio F690/F730. The differential dynamics of the chlorophyll content and the photosynthetic activity between the needles of 'healthy' and damaged spruces during the year 1989 (4 sampling dates) are presented. (orig.).

  2. Effects of Different Levels of Water Stress on Leaf Water Potential, Stomatal Resistance, Protein and Chlorophyll Content and Certain Anti-oxidative Enzymes in Tomato Plants

    Institute of Scientific and Technical Information of China (English)

    Hatem Zgallai; Kathy Steppe; Raoul Lemeur

    2006-01-01

    A greenhouse experiment was performed in order to investigate the effects of different levels of water stress on leaf water potential (ψw), stomatal resistance (rs), protein content and chlorophyll (Chi) content of tomato plants (Lycopersicon esculentum Mill. cv. Nikita). Water stress was induced by adding polyethylene glycol (PEG 6 000) to the nutrient solution to reduce the osmotic potential (ψs). We investigated the behavior of anti-oxidant enzymes, such as catalase (CAT) and superoxide dismutase (SOD), during the development of water stress. Moderate and severe water stress (i.e.ψs= -0.51 and -1.22 MPa, respectively) caused a decrease in ψw for all treated (water-stressed) plants compared with control plants, with the reduction being more pronounced for severely stressed plants. In addition, rs was significantly affected by the induced water stress and a decrease in leaf soluble proteins and Chi content was observed. Whereas CAT activity remained constant, SOD activity was increased in water-stressed plants compared with unstressed plants. These results indicate the possible role of SOD as an anti-oxidant protector system for plants under water stress conditions. Moreover, it suggests the possibility of using this enzyme as an additional screening criterion for detecting water stress in plants.

  3. Adaptive changes in chlorophyll content and photosynthetic features to low light in Physocarpus amurensis Maxim and Physocarpus opulifolius “Diabolo”

    Science.gov (United States)

    Zhang, Huihui; Zhong, Haixiu; Wang, JIfeng; Sui, Xin

    2016-01-01

    The present study aims to investigate the differences in leaf pigment content and the photosynthetic characteristics under natural and low light intensities between the Chinese native Physocarpus amurensis Maxim and the imported Physocarpus opulifolius “Diabolo” from North America. We aim to discuss the responses and the adaptive mechanism of these two cultivars of Physocarpus to a low light environment. The results show that the specific leaf area (SLA) and the chlorophyll content were significantly increased in the leaves of both Physocarpus cultivars in response to a low light intensity, and the SLA and chlorophyll content were higher in the leaves of low light-treated P. opulifolius “Diabolo” compared with the leaves of low light-treated P. amurensis Maxim. Moreover, the content of anthocyanin was markedly reduced in the leaves of P. opulifolius “Diabolo” under low light intensity, which allowed for a greater capacity of photon capture under the low light condition. Under natural light, the photosynthetic carbon assimilation capacity was greater in the leaves of P. amurensis Maxim compared with the leaves of P. opulifolius “Diabolo” that were rich with anthocyanin. However, in response to low light, AQY, Pmax, LCP and LSP decreased to a lesser extent in the leaves of P. opulifolius “Diabolo” compared with the leaves of P. amurensis Maxim. These results suggest that P. opulifolius “Diabolo” exhibits a greater ability in adaption to low light, and it is probably related to the relatively higher chlorophyll content and the smaller SLA in the leaves of P. opulifolius “Diabolo.” In addition, the low light intensity resulted in a reduced photochemical activity of photosystem (PS) II in the leaves of both Physocarpus, as evidenced by increased values of the relative variable fluorescence at point J and point I on the OJIP curve. This result suggests that the electron acceptor in PS II was the major responsive site to the low light stress in

  4. 21 CFR 201.51 - Declaration of net quantity of contents.

    Science.gov (United States)

    2010-04-01

    ... excess volume prescribed by the National Formulary or the U.S. Pharmacopeia for filling of ampules. In... accurate net weight. Variations shall comply with the limitations provided in the U.S. Pharmacopeia or...

  5. Comparison of leaf color chart observations with digital photographs and spectral measurements for estimating maize leaf chlorophyll content

    Science.gov (United States)

    Crop nitrogen management is important world-wide, as much for small fields as it is for large operations. Developed as a non-destructive aid for estimating nitrogen content in rice crops, leaf color charts (LCC) are a numbered series of plastic panels that range from yellowgreen to dark green. By vi...

  6. Processed vs. Non-Processed Biowastes for Agriculture: Effects of Post-Harvest Tomato Plants and Biochar on Radish Growth, Chlorophyll Content and Protein Production

    Science.gov (United States)

    Mozzetti Monterumici, Chiara; Rosso, Daniele; Montoneri, Enzo; Ginepro, Marco; Baglieri, Andrea; Novotny, Etelvino Henrique; Kwapinski, Witold; Negre, Michèle

    2015-01-01

    The aim of this work was to address the issue of processed vs. non-processed biowastes for agriculture, by comparing materials widely differing for the amount of process energy consumption. Thus, residual post harvest tomato plants (TP), the TP hydrolysates obtained at pH 13 and 60 °C, and two known biochar products obtained by 650 °C pyrolysis were prepared. All products were characterized and used in a cultivation of radish plants. The chemical composition and molecular nature of the materials was investigated by solid state 13C NMR spectrometry, elemental analysis and potentiometric titration. The plants were analysed for growth and content of chlorophyll, carotenoids and soluble proteins. The results show that the TP and the alkaline hydrolysates contain lignin, hemicellulose, protein, peptide and/or amino acids moieties, and several mineral elements. The biochar samples contain also similar mineral elements, but the organic fraction is characterized mainly by fused aromatic rings. All materials had a positive effect on radish growth, mainly on the diameter of roots. The best performances in terms of plant growth were given by miscanthus originated biochar and TP. The most significant effect was the enhancement of soluble protein content in the plants treated with the lowest energy consumption non processed TP. The significance of these findings for agriculture and the environment is discussed. PMID:25906472

  7. Evaluation of Leaf Total Nitrogen Content for Nitrogen Management in a Malaysian Paddy Field by Using Soil Plant Analysis Development Chlorophyll Meter

    Directory of Open Access Journals (Sweden)

    A. Gholizadeh

    2009-01-01

    Full Text Available Problem statement: Laboratory plant testing is usually time-consuming and high-costing. Hence, plant nutrient variability must be measured rapidly and the information made known to the farmers before the new season starts. Site-specific crop management, well-established in some developed countries, is now being considered in other places such as Malaysia. Approach: The application of site-specific management principles and techniques to diverse crops and small-scale farming systems in Malaysia will present new challenges. Describing within-field variability in typical Malaysian production settings is a fundamental first step toward determining the size of management zones and the inter-relationships between limiting factors, for establishment of site-specific management strategies. Results: Measurements of rice SPAD readings and nitrogen content were obtained in a Malaysian rice paddy field. SPAD reading data was manually collected on 80DAT and measured using a Minolta SPAD 502. Leaf samples were collected at 60 points at the same time to compare results from sampling with SPAD reading values. Samples nitrogen content was analyzed in a laboratory. Analysis of variance, variogram and kriging were conducted to determine the variability of the measured parameters and also their relationship. SPAD reading and nitrogen content maps were created on the interpretation of the data was investigated. Conclusion/Recommendations: Finally the research indicated that SPAD readings are closely related to leaf N content which means the potential for technology of precision farming to understand and control variation in Malaysian production fields and also SPAD chlorophyll meter ability to monitor the N status of rice and recommend the amount of N fertilization. Additional research is needed to confirm the results with data from other fields and crops.

  8. Effects of abscisic acid or benzyladenine on pigment contents, chlorophyll fluorescence, and chloroplast ultrastructure during water stress and after rehydration

    Czech Academy of Sciences Publication Activity Database

    Haisel, Daniel; Pospíšilová, Jana; Synková, Helena; Schnablová, Renáta; Baťková, Petra

    2006-01-01

    Roč. 44, č. 4 (2006), s. 606-614. ISSN 0300-3604 R&D Projects: GA ČR GA522/04/0549 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : Beta vulgaris * Nicotiana tabacum * Phaseolus vulgaris * starch content * Zea mays Subject RIV: ED - Physiology Impact factor: 0.782, year: 2006

  9. IMPACT OF SALINITY AND SODICITY ON BIOMASS, TOTAL NITROGEN, NITRATE REDUCTASE ACTIVITY, LEAF AREA, AND CHLOROPHYLL CONTENTS IN MAIZE (ZEA MAYS L.

    Directory of Open Access Journals (Sweden)

    M. GUFRAN KHAN*, SHIMELIS*, G., ALEMU, H.* AND KEBENU, F**

    2014-11-01

    Full Text Available ABSTRACT: Salinity and sodicity are major constraint in increasing crop production at global level. Millions of the hectares of the land are too saline to produce economic yield.  In Ethiopia, 11 million ha of land is salt affected, about half of these soils are saline and remaining half are saline - sodic and sodic soil. As most of the arable land and quality water resources have already been exploited, the use of saline or urban/industrial waste water may be a viable alternative for further agro production. In view of such perspectives, an investigation was conducted to examine the effect of salinity (NaCl and sodicity (Na2CO3 on  biomass, total nitrogen, nitrate reductase activity, leaf area, and chlorophyll contents in Maize (Zea mays L. plants. The appropriate amount of NaCl and Na2CO3  was  dissolved in distilled water for appraisal of artificial  salinity and sodicity levels ( 0 , 4, 8,  and 12  and  mScm-1 in soil medium. Plants were also supplied with potassium (0 and 5mM KNO3 as remedial treatment. Maize plants were analyzed for germination, early growth, biomass, total nitrogen, Nitrate reductase activity, Leaf area, and chlorophyll contents as grown under different ECe levels of salinity and sodicity. The extent of salinity and sodicity effects was compared on the basis of different parameters. It was observed that plants showed substantial reduction in all parameters due to imposition of salinity and sodicity in root medium and it was more so due to sodicity. However, the use of additional potassium brought about an enhancement in these parameters.  It is suggested that plants may be raised in saline soil and saline water however; the extent of success depends upon salinity and sodicity levels, remedial treatments and plant species. The outcome of the present work may contribute towards viable utilization of saline soil and water for enhancing agro production of suitable crops, a desired goal to achieve food security.

  10. 16 CFR 503.4 - Net quantity of contents, numerical count.

    Science.gov (United States)

    2010-01-01

    ..., the unit light bulb, and the unit dry cell battery do not require a net quantity statement of “one sponge,” “one light bulb,” or “one dry cell battery.” However, there still exists the necessity...

  11. Impact of salt stress (NaCl on growth, chlorophyll content and fluorescence of Tunisian cultivars of chili pepper (Capsicum frutescens L.

    Directory of Open Access Journals (Sweden)

    Kaouther Zhani

    2012-11-01

    Full Text Available Salinity is considered as the most important abiotic stress limiting crop production and plants are known to be able continuing survive under this stress by involving many mechanisms. In this content, the present study was carried out to evaluate the impact of NaCl on some physiological and biochemical parameters in five Tunisian chili pepper (Capsicum frutescens L. cultivars: Tebourba (Tb, Somaa (Sm, Korba (Kb, Awald Haffouzz (AW and Souk jedid (Sj. Thus, an experiment of five months was carried out under greenhouse at Higher Institute of Agronomy, Chott Meriem, Tunisia and stress is induced by NaCl at 7 concentrations (0, 2, 4, 6, 8, 10 and 12g/l. Results showed that increasing salinity stress, for all cultivars, had a negative impact on roots (length, fresh and dry weights and leaves (number and area. Also, chlorophyll (a and b amount in addition to quantium yield (Fv/Fm decreased significantly. However, biosynthesis of proline in leaves is activated. Awlad Haffouzz and Korba cultivars succefully tolerated highest salinity level by accumulating more proline in leaves and maintaining usually higher values in all parameters in opposition to Souk jedid cultivar. Taken together, our data partly explain the mechanism used to ovoid salt stress by pepper plants when excessive in the culture medium.

  12. Effect of 2,4-dichlorophenoxyacetic acid on growth, protein and chlorophyll-a content of Chlorella vulgaris and Spirulina platensis cells.

    Science.gov (United States)

    Saygideger, Saadet Demirors; Okkay, Ozlem

    2008-03-01

    In this study, effect of different 2,4 -dichlorophenoxyacetic acid (2,4-D) concentrations (0.0, 9.10(-5), 9.10(-4), 9.10(-3) and 9.10(-2) mM) on growth rate, content of protein and chlorophyll-a in Chlorella vulgaris and Spirulina platensis cells was investigated. The most stimulatory effect on growth rate, protein and pigment ratio of C. vulgaris and S. platensis was observed at 9.10(-4) mM concentrations of 2,4-D. The results show that low concentrations of 2,4-D have hormonal effect due to being a synthetic auxin. Cell number protein and pigment rates were inhibited at 9.10(-2) mM concentration in C. vulgaris. Such parameters were inhibited in S. platensis, both at 9.10(-3) and 9.10(-2) mM 2,4-D concentrations. This is due to herbicidal effect of high concentrations of 2,4-D. S. platensis was found to be more sensitive than S. vulgaris to 2,4-D applications. The use of algae as bio-indicators in herbicide contaminated fresh water habitats, was discussed. PMID:18831369

  13. A Mixed-Methods Study of Patient-Provider E-Mail Content in a Safety-Net Setting.

    Science.gov (United States)

    Mirsky, Jacob B; Tieu, Lina; Lyles, Courtney; Sarkar, Urmimala

    2016-01-01

    To explore the content of patient-provider e-mails in a safety-net primary care clinic, we conducted a content analysis using inductive and deductive coding of e-mail exchanges (n = 31) collected from January through November 2013. Participants were English-speaking adult patients with a chronic condition (or their caregivers) cared for at a single publicly funded general internal medicine clinic and their primary care providers (attending general internist physicians, clinical fellows, internal medicine residents, and nurse practitioners). All e-mails were nonurgent. Patients included a medical update in 19% of all e-mails. Patients requested action in 77% of e-mails, and the most common requests overall were for action regarding medications or treatment (29%). Requests for information were less common (45% of e-mails). Patient requests (n = 56) were resolved in 84% of e-mail exchanges, resulting in 63 actions. These results show that patients in safety-net clinics are capable of safely and effectively using electronic messaging for between-visit communication with providers. Safety-net systems should implement electronic communications tools as soon as possible to increase health care access and enhance patients' involvement in their care. PMID:26332306

  14. 基于高光谱图像的黄瓜叶片叶绿素含量分布检测%Detection of chlorophyll content distribution in cucumber leaves based on hyperspectral imaging

    Institute of Scientific and Technical Information of China (English)

    邹小波; 张小磊; 石吉勇; 李志华; 申婷婷

    2014-01-01

    植物叶片叶绿素含量及分布是植物营养信息表达的重要指标。为了给大棚黄瓜营养元素的控制提供理论依据,该研究利用高光谱图像建立简单实用的光谱值和叶绿素含量关系的模型,从而实时、无损地检测叶片的叶绿素分布。选取黄瓜叶片的高光谱图像数据块中450~850 nm波段作为研究波段。选取8个具有代表性的植被指数,建立特征波长λ下相应的光谱反射值 Rλ与黄瓜叶片叶绿素含量之间的关系模型。结果显示,基于最优指数(R695-705)-1-(R750-800)-1的模型可以很好地预测黄瓜叶片叶绿素的含量,校正集和预测集相关系数 r 分别为0.8410和0.8286,最小均方根误差RMSE分别为0.2045和0.2190 mg/g。最后根据最优模型预测叶片上任意位置叶绿素的含量,并通过伪彩手段描述叶绿素含量的分布。研究结果表明,利用高光谱图像技术分析黄瓜叶片叶绿素含量及其在叶面上的分布是可行的。另外,该研究确定的最优植被指数所包含的695~705和750~800 nm 2个波段可用于搭建更加简便实用的快速检测叶片叶绿素的便携式多光谱设备。%The content and distribution of chlorophyll in leaves are important indicators of nutrition information in plants. The objective of this study was to investigate the spectral behavior of the relationship between reflectance and chlorophyll content and to develop a technique for non-destructive chlorophyll estimation and distribution in leaves by using hyperspectral images. The hyperspectral imaging data cube of cucumber (Cucumissativus) leaves in the range of 450-850 nm were selected and preprocessed. A rectangle mesophyll about 100×200 pixels between the second and the third branch left of the main vein was selected as the region of interest (ROI). Spectra information of characteristic bands was extracted and used to set a model with measured chlorophyll content (spectra region

  15. 基于高光谱图像的黄瓜叶片叶绿素含量分布检测%Detection of chlorophyll content distribution in cucumber leaves based on hyperspectral imaging

    Institute of Scientific and Technical Information of China (English)

    邹小波; 张小磊; 石吉勇; 李志华; 申婷婷

    2014-01-01

    The content and distribution of chlorophyll in leaves are important indicators of nutrition information in plants. The objective of this study was to investigate the spectral behavior of the relationship between reflectance and chlorophyll content and to develop a technique for non-destructive chlorophyll estimation and distribution in leaves by using hyperspectral images. The hyperspectral imaging data cube of cucumber (Cucumissativus) leaves in the range of 450-850 nm were selected and preprocessed. A rectangle mesophyll about 100×200 pixels between the second and the third branch left of the main vein was selected as the region of interest (ROI). Spectra information of characteristic bands was extracted and used to set a model with measured chlorophyll content (spectra region extracted corresponding to region chlorophyll measured). The existing modeling methods, such as artificial neural networks (ANN), support vector machines (SVM), etc., can be used to achieve better results but are inconvenient for online applications due to the introduction of sophisticated algorithms. As an operation result of multiple spectrum values (addition, subtraction, multiplication, and division, combined with linear or nonlinear ways), vegetation indices, which play a role in indicating growth and biomass of vegetation, are significant in simplifying the model. Eight representative optical indices (or signatures), which were proposed as a function of the associated reflectance (Rλ) at the special wavelength (λ) nm, were used to predict the total chlorophyll content in cucumber leaves. Finally, (R695-705)-1-(R750-800)-1was identified as an optimum index, predicting the content of chlorophyll fairly well. The correlation coefficients of each model for calibration data set (rc) and validation data set (rp) were 0.8410 and 0.8286, while RMSEC (root mean square error of calibration) and RMSEP (root mean square error of predication) were the smallest (0.2045 mg/g and 0.2190 mg/g). The

  16. Genetic Analysis and Molecular Mapping of a Novel Chlorophyll-Deficit Mutant Gene in Rice

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiao-qun; WANG Ping-rong; ZHAO Hai-xin; DENG Xiao-jian

    2008-01-01

    A rice etiolation mutant 824ys featured with chlorophyll deficiency was identified from a normal green rice variety 824B.It showed whole green-yellow plant from the seedling stage,reduced number of tillers and longer growth duration.The contents of chlorophyll,chlorophyll a,chlorophyll b and net photosynthetic rate in leaves of the mutant obviously decreased,as well as the number of spikelets per panicle,seed setting rate and 1000-grain weight compared with its wild-type parent.Genetic analyses on F1 and F2 generetions of 824ys crossed with three normal green varieties showed that the chlorophyll-deficit mutant character was controlled by a pair of recessive nuclear gene.Genetic mapping of the mutant gene was conducted by using microsatellite markers and F2 mapping population of 495R/824ys,and the mutant gene of 824ys was mapped on the shon arm of rice chromosome 3.The genetic distances from the target gene to the markers RM218,RM282 and RM6959 were 25.6 cM,5.2 cM and 21.8 cM,respectively.It was considered to be a now chlorophyll-deficit mutant gene and tentatively named as chl11(t).

  17. 16 CFR 500.7 - Net quantity of contents, method of expression.

    Science.gov (United States)

    2010-01-01

    ... liquid, or in terms of weight or mass if the commodity is solid, semi-solid, or viscous, or a mixture of solid and liquid. If there is a firmly established general consumer usage and trade custom of declaring the contents of a liquid by weight or mass, or a solid, semi-solid, or viscous product by...

  18. Responses of winter wheat photosynthetic characteristics and chlorophyll content to water-retaining agent and N fertilizer%冬小麦光合特征及叶绿素含量对保水剂和氮肥的响应

    Institute of Scientific and Technical Information of China (English)

    杨永辉; 吴普特; 武继承; 赵世伟; 黄占斌; 何方

    2011-01-01

    The effects of water-retaining agent (60 kg · hm-2) and nitrogen fertilizer (0,225, and 450 kg · hm-2 ) on the leaf photosynthetic characteristics, chlorophyll content, and water utilization of winter wheat at jointing and grain-filling stages were studied under field conditions. In all treatments, the net photosynthetic rate, stomata conductance, intercellular CO2 concentration, water use efficiency, and chlorophyll content were greater at grain-filling stage than at jointing stage. Under nitrogen fertilization but without water-retaining agent application, the water use efficiency (WUE) of single leaf at jointing stage increased with increasing nitrogen fertilization rate, while the net photosynthetic rate, stomata conductance, intercellular CO2 concentration, and transpiration rate decreased after an initial increase. The chlorophyll content was the highest under 225 kg · hm-2 nitrogen fertilization. In the treatments of water-retaining agent application, the intercellular CO2 concentration decreased with increasing nitrogen application rate, but the net photosynthetic rate, transpiration rate, and WUE increased. The application of water-retaining agent or its combination with nitrogen fertilization increased the chlorophyll content, but excessive nitrogen fertilization had lesser effects. At grain-filling stage, applying nitrogen fertilizer alone significantly increased the net photosynthetic rate and WUE, but decreased the stomata conductance, intercellular CO2 concentration,and transpiration rate. The chlorophyll content increased with increasing nitrogen application rate.After applying water-retaining agent and with the increase of nitrogen fertilization rate, the photosynthetic rate and WUE decreased after an initial increase, while the intercellular CO2 concentration and transpiration rate were in adverse but still lower than those without water-retaining agent application. The stomata conductance increased with increasing nitrogen fertilization rate

  19. Effects of Covering on Growth Potential and Chlorophyll Content of Hardwood Cutting of Lycium barbarum%覆盖对枸杞硬枝扦插苗生长势及叶绿素含量的影响

    Institute of Scientific and Technical Information of China (English)

    张巨琼; 蔺海明; 林楠

    2011-01-01

    Objective:To study the effect of plastic Him covering, straw covering, plastic film covering in greenhouse and no-covering cutting on growth and Chlorophyll content of Lycium barbarian hardwood cutting seedlings. Methods: Single factor randomized block design method was used in this research. Results: The effect of different covering treatments on germination rate, seedling rate and growth potential were all plastic film covering in greenhouse > plastic film covering > straw covering > no-covering cutting. Chlorophyll a, Chlorophyll b, Chlorophyll a + b content and Ca/Cb were significantly different with different coverings in different periods. Conclusion: The optimal covering on hardwood cutting of Lycium barbarum is plastic film covering in greenhouse. Both plastic film and straw covering are better than no-covering cutting.%目的:研究地膜覆盖、麦草覆盖、地膜+弓棚覆盖和露地扦插对枸杞硬枝扦插苗生长势及叶绿素含量的影响.方法:采用单因素随机区组设计.结果:覆盖对枸杞硬枝扦插苗萌芽率、成苗率及生长势的影响均为地膜+弓棚覆盖>地膜覆盖>麦草覆盖>露地扦插;不同处理及不同时期的叶绿素a、b、(a+b)含量和叶绿素(a/b)值均差异显著.结论:枸杞硬枝扦插育苗的最佳覆盖方式为地膜+弓棚覆盖,地膜覆盖和麦草覆盖亦优于露地扦插.

  20. Changes in the Chlorophyll Content and Cytokinin Levels in the Top Three Leaves of New Plant Type Rice During Grain Filling

    Czech Academy of Sciences Publication Activity Database

    Rubia, L.; Rangan, L.; Kamínek, Miroslav; Dobrev, Petre; Malbeck, Jiří; Fowler, M.; Khush, G.; Elliott, M.

    2014-01-01

    Roč. 33, č. 1 (2014), s. 66-76. ISSN 0721-7595 R&D Projects: GA MŠk 1M06030 Institutional support: RVO:61389030 Keywords : Chlorophyll * Cytokinins * Grain filling Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.237, year: 2014

  1. Sea and land surface temperatures, ocean heat content, Earth's energy imbalance and net radiative forcing over the last decade

    Science.gov (United States)

    Dieng, Habib B.; Cazenave, Anny; Meyssignac, Benoit; Schuckmann, Karina

    2016-04-01

    The Earth's global mean surface temperature (GMST) has increased less rapidly since the early 2000s than during the previous decades. Here we investigate the regional distribution of the reported temperature slowdown, focusing on the 2003-2014 decade of most complete global datasets. We find that both land surface temperature (LST) and sea surface temperature (SST) have increased at a rate significantly lower than over the previous decades with small regional differences. While confirming cooling of eastern tropical Pacific during the last decade, our results show that the reduced rate of change is a global phenomenon. We further evaluate the time derivative of full-depth ocean heat content to determine the planetary energy imbalance based on three different approaches: in situ measurements, ocean reanalysis and an indirect measure through the global sea level budget. For the 2003-2014 time span, it is estimated to 0.5 +/- 0.06 Wm-2, 0.64 +/- 0.04 Wm-2, and 0.6 +/- 0.07 Wm-2, respectively for the 3 approaches. We constrain the ocean heat uptake rates using the EBAF energy imbalance time series from the CERES/TOA project and find significant agreement at interannual scales. Finally, we compute the net radiative forcing of the last decade, considering the radiative feedback from observed GMST and the 3 different rates of the total ocean heat content. We obtain values of 1.6 +/- 0.19 Wm-2, 1.75 +/- 0.17 Wm-2, and 1.70 +/- 0.19 Wm-2, respectively over 2003-2014. We find no evidence of decrease in the net radiative forcing in the recent years, but rather increase compared to the previous decades.

  2. Chlorophylls - natural solar cells

    CERN Document Server

    Jantschi, Lorentz; Balan, Mugur C; Sestras, Radu E

    2011-01-01

    A molecular modeling study was conducted on a series of six natural occurring chlorophylls. Quantum chemistry calculated orbital energies were used to estimate frequency of transitions between occupied molecular orbital and unoccupied molecular orbital energy levels of chlorophyll molecules in vivo conditions in standard (ASTMG173) environmental conditions. Obtained results are in good agreement with energies necessary to fix the Magnesium atom by chlorophyll molecules and with occurrence of chlorophylls in living vegetal organisms.

  3. 镧对UV-C胁迫下番茄幼苗叶绿素含量的影响%Effects of La(3+)on Chlorophyll Content in Tomato Seedlings under UV-C Stress

    Institute of Scientific and Technical Information of China (English)

    李海平; 张惠; 李灵芝; 郑少文

    2011-01-01

    在温室中研究了La(3+)对UV-C辐射胁迫下番茄幼苗光合色素含量的影响.结果表明:La(3+)能够显著缓解UV-C辐射胁迫对光合色素的降解作用,与单一UV-C胁迫组相比,番茄幼苗叶绿素a平均提高了17.65%、叶绿素b平均提高了17.11 %;La(3+)可以缓解类胡萝卜素在UV-C胁迫下的降解,使其维持较高水平.综合比较得出,30 mg/L LaCl3在UV-C辐射胁迫下对番茄幼苗的防护效果好于60 mg/L LaCl3.%The effects of La3+on the chlorophyll content in tomato seedlings were examined under UV-C radiation stress in greenhouse. The results showed that La3+ could significantly relieve the degradation effect of chlorophyll stressed by UV-C radiation. Compared with the single UV-C stress group, chlorophylla increased 17.65% by La3+ averagely, chlorophyll b 17.11% and La3+ could relieve the carotenoid degradation in tomato seedling under UV-C radiation stress to keep carotenoid content in tomato seedlings maintained at a relatively high level. By comprehensive comparison of various index, 30 mg/L LaCl3 had a better protective effect than 60 mg/L LaCl3 under UV-C radiation stress.

  4. Investigating the impact of NaCl salinity on growth, β-carotene, and chlorophyll a in the content life of halophytes of algae Chlorella sp.

    Directory of Open Access Journals (Sweden)

    Mojtaba Fathi

    2013-05-01

    Full Text Available Algae are used for many purposes as: food industry, animal feeding, soil enrichment andbiodiesel production. Chlorella is widely cultivated from microalgae species as it is rich in nutrients andhas its implementation as a healthy food use. In this study, the impact of NaCl salinity on growth, betacarotene,and chlorophyll a of Chlorella sp. has been investigated. This study results in three salinities(10, 30, 50 g L-1, respectively have shown that 30 g L-1 concentration has the highest value of cellnumber in day 15th and there was no significant difference between salinities on day 15th (p>0.05. Βetacaroteneresult has shown 50 g L-1 salinity and the highest value of beta-carotene did not indicate anystatistically significant differences between treatments (p>0.05. Chlorophyll a result has shown highestvalue in all treatments (it was in 50 g L-1. However, there was no significant difference betweensalinities on day 5th (p>0.05.

  5. Teor de clorofila e perfil de sais minerais de Chlorella vulgaris cultivada em solução hidropônica residual Chlorophyll content and minerals profile in the microalgae Chlorella vulgaris cultivated in hydroponic wastewater

    Directory of Open Access Journals (Sweden)

    Fabiano Cleber Bertoldi

    2008-02-01

    Full Text Available O cultivo de microalgas representa uma potencial fonte de biomassa rica em clorofila e sais minerais como: fósforo, ferro, manganês, cobre, zinco, magnésio e cálcio. Este experimento teve como objetivo avaliar a composição de minerais, bem como determinar o teor de clorofila a e b da microalga Chlorella vulgaris cultivada em solução hidropônica residual em três diferentes concentrações comparadas com um cultivo controle. Os resultados mostraram que os teores de clorofila a e b da microalga não apresentaram diferença significativa entre os cultivos. Com relação à composição dos sais minerais, a Chlorella cultivada na solução residual mais concentrada apresentou valores superiores quando comparada com a cultivada nos demais cultivos. Dessa forma, a biomassa da Chlorella vulgaris demonstrou ser uma potencial fonte de clorofila e de sais minerais, quando cultivada em solução hidropônica residual, possibilitando a utilização desse resíduo de forma sustentável.The microalgaes cultive represents a potential source of biomass rich in chlorophyll and minerals as: P, Fe, Mn, Cu, Zn, Mg and Ca. This research was aimed at evaluating the composition of minerals, as well as, determining the content of chlorophyll a and b from the microalgae Chlorella vulgaris cultivated in hydroponic wastewater in three different concentrations compared with the control cultive. The results showed that the contents of chlorophyll a and b of the microalgae did not show significant difference between the cultives. In relation to the composition of the minerals, the Chlorella cultivated in the most concentrated wastewater, showed higher values when compared with the one cultivated in the others cultures. In this manner, the Chlorella vulgaris biomass demonstrated to be a potential source of chlorophyll and minerals, when cultivated in hydroponic wastewater, allowing the use of this residue in a sustainable way.

  6. 基于叶绿素荧光光谱的生菜硝酸盐含量检测%Detection of nitrate content in lettuce based on chlorophyll fluorescence spectrum

    Institute of Scientific and Technical Information of China (English)

    王琳琳; 于海业; 张蕾; 赵红星

    2016-01-01

    为了寻求生菜叶片硝酸盐含量的快速无损检测方法,该文利用叶绿素荧光光谱分析技术对生菜(Lactuca sativa L.)叶片硝酸盐含量进行检测研究。对比及分析500~550、650~715和715~800 nm 3个波段的叶绿素荧光光谱特征参数与生菜叶片硝酸盐含量的关系,得出650~715 nm 波段的叶绿素荧光光谱特征参数与生菜叶片硝酸盐含量之间线性关系显著,决定系数 R2为0.816,标准误差为0.147,以此建立的回归模型能够很好地反映生菜叶片硝酸盐含量与叶绿素荧光光谱特征参数的关系;将同批进行试验的30个样本作为回归方程的校验集,进行模型验证,预测值与实测值之间决定系数R2为0.752,表明回归模型对生菜叶片硝酸盐含量有良好的预测效果。研究结果为生菜叶片硝酸盐含量的快速无损检测提供参考。%With the development of spectral technology, many researchers have done a lot of research on the nondestructive testing methods of nitrate content in leaves and have achieved some results. However, most of the studies have used visible and near infrared spectroscopy or mid infrared spectroscopy technology, and the chlorophyll fluorescence spectrum technology is still not used. Therefore, this paper used chlorophyll fluorescence spectrum analysis technology to study the relationship between nitrate content and fluorescence spectrum. With aerosol cultured lettuce as the research object, the chlorophyll fluorescence spectrum characteristic parameters were extracted to establish the function relationship between the characteristic parameters of chlorophyll fluorescence spectrum and the nitrate content of lettuce leaves, which laid a theoretical foundation for the rapid and nondestructive detection of nitrate content in lettuce leaves. The peak values of fluorescence intensity of 500-550, 650-715 and 715-800 nm were the characteristic parameters of chlorophyll fluorescence

  7. Chlorophyll loss associated with heat-induced senescence in bentgrass.

    Science.gov (United States)

    Jespersen, David; Zhang, Jing; Huang, Bingru

    2016-08-01

    Heat stress-induced leaf senescence is characterized by the loss of chlorophyll from leaf tissues. The objectives of this study were to examine genetic variations in the level of heat-induced leaf senescence in hybrids of colonial (Agrostis capillaris)×creeping bentgrass (Agrostis stolonifera) contrasting in heat tolerance, and determine whether loss of leaf chlorophyll during heat-induced leaf senescence was due to suppressed chlorophyll synthesis and/or accelerated chlorophyll degradation in the cool-season perennial grass species. Plants of two hybrid backcross genotypes ('ColxCB169' and 'ColxCB190') were exposed to heat stress (38/33°C, day/night) for 28 d in growth chambers. The analysis of turf quality, membrane stability, photochemical efficiency, and chlorophyll content demonstrated significant variations in the level of leaf senescence induced by heat stress between the two genotypes, with ColXCB169 exhibiting a lesser degree of decline in chlorophyll content, photochemical efficiency and membrane stability than ColXCB190. The assays of enzymatic activity or gene expression of several major chlorophyll-synthesizing (porphobilinogen deaminase, Mg-chelatase, protochlorophyllide-reductase) and chlorophyll-degrading enzymes (chlorophyllase, pheophytinase, and chlorophyll-degrading peroxidase) indicated heat-induced decline in leaf chlorophyll content was mainly due to accelerated chlorophyll degradation, as manifested by increased gene expression levels of chlorophyllase and pheophytinase, and the activity of pheophytinase (PPH), while chlorophyll-synthesizing genes and enzymatic activities were not differentially altered by heat stress in the two genotypes. The analysis of heat-induced leaf senescence of pph mutants of Arabidopsis further confirmed that PPH could be one enzymes that plays key roles in regulating heat-accelerated chlorophyll degradation. Further research on enzymes responsible in part for the loss of chlorophyll during heat

  8. 柑橘叶片叶绿素含量高光谱无损检测模型%Non-destructive hyperspectral measurement model of chlorophyll content for citrus leaves

    Institute of Scientific and Technical Information of China (English)

    岳学军; 全东平; 洪添胜; 王健; 瞿祥明; 甘海明

    2015-01-01

    针对柑橘叶片叶绿素含量的传统化学检测,不仅耗时长且损伤柑橘叶片,还依赖检测者实操技术,无法集成于精细农业中变量喷施农机具的诸多弊端,该文探讨快速无损检测柑橘叶片叶绿素含量方法。以117棵园栽萝岗甜橙树为研究对象,选用ASD FieldSpec 3光谱仪对萌芽期、稳果期、壮果促梢期、采果期共4个生长时期的柑橘叶片进行高光谱反射率采集,并同步采用分光光度法测得叶片的叶绿素含量;以原始光谱及其变换形式作为模型输入矢量,分别在主成分分析(principle component analysis,PCA)降维的基础上利用支持向量机回归(support vector regression,SVR)算法和在小波去噪的基础上利用偏最小二乘回归(partial least square regression,PLSR)算法对柑橘叶片叶绿素含量进行建模预测,全生长期整体建模的校正集和验证集最佳模型决定系数 R2分别为0.8713和0.8670,均方根误差 RMSE (root-mean-square error)分别为0.1517和0.1544,试验结果表明,高光谱可快速无损地对柑橘叶片叶绿素含量进行精确的定量检测,为柑橘不同生长期的营养监测提供理论依据。%Traditional methods of obtaining chlorophyll content of citrus leaves require grinding citrus leaves and applying chemical titrations, which would be harmful to citrus trees and time-consuming. Besides, it's difficult to integrate those chemical methods into variable spraying system as a feedback subsystem. In this paper, we discuss several rapid and non-destructive methods in obtaining chlorophyll content of citrus leaves by using hyperspectral analysis system. Hyperspectral technology obtains synchronously spectrum in continuous space, where we can derive crop growth information visually in a non-destructive way. In this paper, the modeling of chlorophyll content of citrus leaves based on the hyperspectrum was discussed. Field experiments were

  9. 竹炭有机肥对有机卷心菜叶绿素荧光特性和相对叶绿素含量的影响%Effect of bamboo charcoal organic fertilizer on chlorophyll fluores-cence characteristics and relative chlorophyll content of organic cab-bage

    Institute of Scientific and Technical Information of China (English)

    马锦丽; 黄鹤凤; 江洪; 舒海燕; 张金梦; 吴丹娜; 孙文文; 吴孟霖; 方成圆; 陈晓峰

    2015-01-01

    Selecting organic cabbage in Chongming of Shanghai dol y farm as the research object, and set up three bamboo charcoal organic fertilizer processing:BC180 (180 kg/20 m × 20 m), BC60 (60 kg/20 m × 20 m), CK (control), During July(Rosette period) and August(Fruit period) in 2014, its chlorophyl fluorescence kinetics parameter and relative chlorophyl content is determined by a random and relative method, in order to analyze the influence of bamboo charcoal organic fertilizer on the organic cabbage.The results showed that different growth period under the same processing, organic cabbage leaf blade light systemⅡ(PSⅡ), initial fluorescence (F0), the largest fluorescence (Fm), maximum photochemical efficiency (Fv/Fm), potential photosynthetic activity (Fv/F0), the actual photochemical efficiency (Yield) were rosette period > fruit period; Apparent photosynthetic electron transport rate (ETR), coefficient of photochemical quenching (qP) and relative chlorophyl content (SPAD) was fruit period>rosette period. The same growth period under different processing, Fv/Fm, Fv/F0, Yield, ETR, qP were increasing as fertilizer rate increasing, NPQ increases during rosette period, and became lower during knot bal period. Different growth period and fertilizer's interaction on Fm, Fv/Fm, Fv/F0, NPQ were very significant (P结球期;表观光合电子传递速率(ETR)、光化学淬灭系数(qP)、相对叶绿素含量(SPAD)为结球期>莲座期。同一生长期不同处理下,Fv/Fm、Fv/F0、Yield、ETR、qP均是随着施肥量增加而增加,NPQ则为莲座期增加,结球期又降低。不同生长期不同施肥量交互作用对Fm、Fv/Fm、Fv/F0、NPQ影响极显著(P<0.01),对qP影响显著(P<0.05)。这说明增施竹炭有机肥对有机卷心菜叶绿素荧光指标和相对叶绿素含量有显著影响,且BC60处理下更有助于其光合固碳,增加产量,符合低碳有机农业宗旨。

  10. Analysis on the blending inheritance of popcorn leaves' chlorophyll contents%爆裂玉米叶片叶绿素含量的混合遗传分析

    Institute of Scientific and Technical Information of China (English)

    包和平; 毕成龙; 李颖; 王利强

    2011-01-01

    应用植物数量性状主基因+多基因混合遗传模型,以爆裂玉米杂交组合吉爆902(吉812×吉704)的P1、F1、P2、B1 2、B2 2和F2∶3 6个家系世代群体为材料,对爆裂玉米叶片叶绿素含量进行多世代联合分析.结果表明:叶绿素含量受1对加性-显性主基因+加性-显性-上位性多基因控制遗传.主基因加性效应为d=-0.0247,主基因显性效应值为h=0.0511.主基因存在显性效应,该组合的叶绿素含量存在杂种优势.B2∶2和F2∶3,家系群体主基因遗传力分别为55.28%和42.12%,多基因遗传率分别为26.36%和34.11%.%Six populations(P1, F1, P2, B1:2, B2:2 and F2:3)of popcorn hybridized combination Jibao 902(Ji 812 × Ji 704)were used as test materials,and their leaves'chlorophyll contents were jointly analyzed according to the major gene and polygene blending inheritance model of plant quantitative traits.The results showed that the chlorophyll content was genetically controlled by a pair of additivedominant major genes and additive-dominant-epistatic polygene.The additive effect value and dominant effect value of the major genes were d = - 0.0247 and h = 0.0511 ,respectively.The major gene had a dominant effect, and the combination had heterosis in chlorophyll content.The B2:2 and F2:3 populations were respectively 55.28% and 42.12% in the major gene heritability, and respectively 26.36% and 34.11% in the polygene heritability.

  11. 水分胁迫对华北景天叶片结构和叶绿素含量的影响%Effect of Water Stress on the Structure and Chlorophyll Content of S.tatarinowii Maxim Leaves

    Institute of Scientific and Technical Information of China (English)

    那冬晨; 王文斗; 杨丽静; 张婧; 任彩琴; 柴婷婷

    2011-01-01

    [目的]研究水分胁迫对华北景天(Sedum tuarinowii Maxim)叶片结构和叶绿素含量的影响,为其更广泛应用提供参考.[方法]取山西省霍山七里峪国家森林公园的野生华北景天,经过人工栽培后进行水分胁迫.试验共设4组,土壤绝对含水量分别为17.50%、13.60%、9.60%、6.20%,以土壤绝对含水量17.50%为对照.土壤绝对含水量采用烘干称重法测定;叶片中叶绿素含量采用丙酮浸提法测定;取生长良好、洁净的叶片,制备石蜡切片和表皮制片,观察气孔器类型和分布特征,测定气孔密度.[结果]在正常条件下,华北景天叶片表面具薄的蜡质层,叶内有发达的储水组织,并分布有吸水能力较强的异细胞;气孔白天关闭,夜晚开启,气孔器下陷;水分胁迫下,上表皮出现了发育不完全的气孔,成熟气孔密度呈下降趋势,下表皮气孔密度变化不明显.华北景天叶绿素a、b对活性氧的反应差异不明显,而且在一定程度的干旱条件下叶绿素含量有所增加;土壤绝对含水量为9.60%时,华北景天可维持正常光合作用;当土壤绝对含水量下降到6.20%时,叶绿素含量有所下降.[结论]华北景天具有典型的旱生植物形态特征,在较低的土壤绝对含水量时,叶绿素含量可保持不变或稳定增加的趋势,维持植物正常光合作用.%[Objective] To study the effect of water stress on the structure and chlorophyll content of S. Tatarinouii Maxim leaves, so as to provide references for its wide application. [ Method] Wild S. Tatarinowii Maxim sampled from Qiliyu National Forestry Park in Huoshan of Shanxi Prov ince were cultivated and then treated by water stress. Four groups were set up with the absolute water content in soil of 17.50% , 13.60% ,9.60% and 6.20% respectively,among which 17.50% was the control. The absolute water content of soil was determined by dry weighting method; while the chlorophyll content in the

  12. Chlorophyll Degradation in Horticultural Crops

    OpenAIRE

    Kaewsuksaeng, Samak

    2011-01-01

    One of the symptoms of senescence in harvested horticultural crops is the loss of greenness that comes with the degradation of chlorophyll. With senescence, the chlorophyll-degrading enzyme activities such as chlorophyllase, Mg-dechelatase or Mg-dechelation activity, a new chlorophyll-degrading enzyme, pheophytinase, pheophorbidase and chlorophyll-degrading peroxidase, which are involved in chlorophyll degradation, affected greatly in stored horticultural crops. The chlorophyll derivatives, e...

  13. 三色堇叶片叶绿素质量分数、气孔特征及光合特性%Chlorophyll Content, Stomatal Responses and Photosynthetic Characteristics of Pansy Leaves

    Institute of Scientific and Technical Information of China (English)

    杜晓华; 刘会超; 袁少寒; 李倩青

    2011-01-01

    Four pansy cultivars, 08-H2, 229-18, EP1 and ZMY2-1, introduced from Dutch, Jiuquan, Shanghai and Zhengzhou respectively, were used as materials to investigate the chlorophyⅡ content, stomatal responses and photosynthetic characteristics of pansy leaves. Results show that the average content of chlorophyll-a of the four pansy cultivars is 1.06 mg/g, and that of chlorophyll b is 1.93 mg/g. The chlorophyll-b content of EP1 is significantly higher than that of ZMY2-1. No difference in chlorophyll-a content was observed among the four cultivars. The stomata density and size of pansy leaves are 97.09 individuals/mm2 and 17.74 μm×l2.31 μm respectively. There is no significant difference in stoma density and size among the four pansy cultivars. Pansy belongs to C3 plant due to its high light saturation point and light compensation. The highest light saturation point of 08-H2 reflects 08-H2 is a heliophilous cultivar. The light saturation point and compensation point of EP1 are lowest, indicating its ability to endure low light. CO2 saturation point of the four pansy cultivars reached the designed maximum of CO2 concentration ( 2 000 μmol · mol-1 ) in this study. The lowest CO2 compensation point and the highest carboxylation efficiency of 08-H2 exhibited its high carboxylase activity of Rubisco at low concentration of CO2.%以4个不同地区来源的三色堇品种08-H2(荷兰)、229-18(酒泉)、EP1(上海)和ZMY2-1(郑州)为试材,研究了其叶片叶绿素质量分数、气孔特征对光强和CO2的响应特性.结果表明:①4个三色堇品种叶片叶绿素a的质量分数平均为1.06mg/g,叶绿素b为1.93mg/g.品种EP1的叶绿素b的质量分数显著高于ZMY2-1,4个品种在叶绿素a的质量分数上无差异.②三色堇叶片气孔密度平均为97.09个/mm2,气孔大小为17.74μm×12.31 μm,品种间无显著差异.③三色堇的光饱和点和光补偿点较高,具有阳生C3植物的特点.08-H2的高光饱和点,

  14. EM菌剂对苔藓生长和叶绿素含量的影响%Effect of EM Bacterium Agent on Growth and Chlorophyll Content of Mosses

    Institute of Scientific and Technical Information of China (English)

    代丽华; 刘方; 李波; 敖成红; 梁春芳

    2011-01-01

    Three mosses of Esmeralda clarkei , Bryum anagustirete and Haplocladium angustifolium were treated by different EM bacterium agent with different concentrations to study the effect of EM bacterium agent on moss growth. The results show that low concentration of EM bacterium agent can promote growth of E. clarkei and B. anagustirete, both the best when treated by EM bacterium agent of 600 times; EM bacterium agent of 200 times showed obvious inhibition effect on the growth of E. clarkei; There was no significant difference between that of B. anagustirete and CK. The total chlorophyll contents of three mosses increased significantly when treated by different concentrations of EM bacterium agent, the total chlorophyll contents of B. anagustirete and H. angusti folium treated by EM bacterium agent of 600 times reached the maximum, 70. 1% and 55. 8% higher than CK respectively, and that of E. clarkei treated by EM bacterium agent of 400 times was the highest, 26. 3% higher than CK. Different concentrations of EM bacterium agent had little influence on Chlorophyll a/b of the three mosses.%为了研究EM菌剂对苔藓生长的影响,对3种苔藓穗枝赤齿藓、狭网真藓和狭叶小羽藓进行了不同浓度EM菌剂处理试验.结果表明:低浓度EM菌剂可促进穗枝赤齿藓、狭叶小羽藓的生长,两者均以600倍液最高;200倍液EM菌剂对穗枝赤齿藓的生长表现出了明显的抑制作用;EM菌液对狭网真藓的影响与对照相比差异不显著.不同浓度EM菌剂处理均显著提高了3种苔藓的总叶绿素含量,其中,狭网真藓、狭叶小羽藓在600倍液EM菌剂处理下,总叶绿素含量最高,与对照相比分别提高了70.1%和55.8%,而穗枝赤齿藓在400倍液EM菌剂处理下达到最大值,比对照提高了26.3%;不同浓度EM菌剂对3种苔藓的叶绿素a/b比率影响不大.

  15. Study of quantitative and qualitative yield, chlorophyll content and some growth indices of wheat (Triticum aestivum L. in response to seed inoculation with PGPR at different levels of soil salinity

    Directory of Open Access Journals (Sweden)

    M. Hagh Bahari

    2014-07-01

    Full Text Available In order to study of quantitative and qualitative yield, chlorophyll content and some growth indices of wheart (Triticum aestivum L. in response to seed inoculation with plant growth promoting rhizobacteria (PGPR at different levels of soil salinity, a factorial experiment based on randomized complete block design with three replications was conducted at Research Greenhouse of Faculty of Agriculture, University of Mohaghegh Ardabili, Ardabil, in 2011. Experimental factors were soil salinity at four levels (0, 15, 30 and 60 Mm as Nacl and seed inoculation with PGPR in four levels (no inoculation as control, seed inoculation with Azotobacter chrocoocum strain 5, Azospirillum lipoferum strain OF, Pseudomonas putida strain 186. Comparison of means showed that in soil salinity conditions, grain yield per plant, number of grain per spike, grain 100 weight, spike length and root weight increased due to seed inoculation with PGPR compared to without seed inoculation. Investigation of total dry matter accumulation indicated that in all treatment combinations, it increased rapidly until 85 days after sowing. From 85 days after sowing till harvest time, it decreased due to increasing of competition, shedding and aging of leaves. In all treatment combinations, the highest grain yield and total dry matter accumulation per unit area was obtained in treatment combination of seed inoculation with Azosperilium × no soil salinity and the lowest amount was in the highest level of soil salinity × no seed inoculation. Similar trend was obtained in crop growth rate and relative growth rate. Hence, the results of this study showed that in order to increase the quantitative and qualitative yield, chlorophyll content and some other growth indices such as total biomass, crop growth rate and relative growth rate of wheat in soil salinity conditions, it could be suggested that wheat seed inoculation with Azospirillum be applied

  16. 氮肥用量对芸豆叶绿素含量和子粒营养品质影响的研究%Effects of Nitrogen Fertilizer Rate on the Chlorophyll Content and Quality of Kidney Bean

    Institute of Scientific and Technical Information of China (English)

    杨亮; 赵宏伟; 宋谨同; 魏淑红; 张亚芝; 王强; 孟宪欣

    2013-01-01

    Four varieties and five nitrogen fertilizer treatments were applied to study the effects of nitrogen fertilizer on the chlorophyll content and nutritional quality of kidney bean. The chlorophyll content in functional leaves of the four varieties presented a single peak curve during the growth period, reaching its highest at the pod bearing stage. The treatment of 30kg pure nitrogen per hector can effectively improve the chlorophyll contents in kidney bean leaves. The grain protein contents of variety Pinyun 2 and Longyun 4 presented bimodal curve after podding, peaks appeared on the 21st day and the 35th day after podding. While grain protein contents of variety British Red and Longyun 6 presented single peak curve after podding, which appeared on the 28th day after podding. Under N30 treatment, the grain protein contents of Pinyun 2, Longyun 6 and Longyun 4 were higher than other treatments; While the grain protein content of British Red shown its highest value under N45 tretment. Considering the grain nutritional quality of kidney bean, the effects of N30 treatment on protein, straight starch, amylopectin, total starch and crude fat is the best.%以4个不同芸豆品种为材料,设5个氮肥处理,研究了不同施氮用量对芸豆功能叶片叶绿素含量和子粒营养品质的影响.结果表明,4个芸豆品种功能叶片叶绿素含量随着生育期的推进呈单峰曲线变化,在结荚期达到峰值;施纯氮30kg/hm2可以有效地提高叶绿素含量.品芸2号和龙芸4号子粒蛋白质含量随着结荚后天数增加呈双峰曲线变化,峰值分别出现在结荚后21d和35d;英国红和龙芸6号子粒蛋白含量呈单峰曲线变化,峰值出现在结荚后28d;在结荚过程中品芸2号、龙芸6号和龙芸4号的N30处理子粒蛋白质含量最高,而英国红则在N45处理时最高.从芸豆子粒营养品质方面来说,N30处理对于蛋白质、直连淀粉、支链淀粉、总淀粉和粗脂肪的影响效果较好.

  17. Effects of Soil Arsenic on Soybean Main Traits and Chlorophyll Content at Different Growing Stage%土壤砷对大豆主要性状及叶绿素含量的影响

    Institute of Scientific and Technical Information of China (English)

    李海波; 杨兰芳; 李亚东

    2013-01-01

    Arsenic is ubiquitous in environment and has high toxicity to animal and plant.Investigating the effects of arsenic on plant growth is important for the recognition of the toxic mechanism of arsenic to plant and the food safety.To understand the relationship between soil arsenic pollution and plant growth,we conducted a soil pot experiment using a soybean variety with adding different amounts of arsenic into soil,in which the soybean growth condition was observed and the plant height,chlorophyll content at podding and grain filling stages and the biomass after harvest were determined.The results showed that visible symptom of arsenic toxicity to soybean was dwarfing of plants,dark green and crimpled leaves,retarded maturity when soil arsenic addition was up to 50 mg kg-1.The soybean plant height decreased and the soybean biomass significantly reduced when high soil arsenic contents.The soybean plant height,soybean stem biomass,aerial part biomass,grain yield and the total soybean biomass decreased by 45.0%,36.6%,44.6%,56.1%,and 43.4%,respectively,in the treatments of 100 mg kg-1 of arsenic.High soil arsenic amounts increased the biomass ratios of roots to aerial parts and stems to aerial parts,but decreased the ratios of grains to aerial parts,grains to stems and grains to total biomass.Soil arsenic amounts had no significant effects on chlorophyll content in soybean leaf but decreased the ratio ofChl a to Chl b at podding stage.At grain filling stage,50 and 100 mg kg-1 arsenic treatments increased 120.4% and 96.1% of Chl a,112.2% and 91.5% of Chl b,117.8% and 94.5% of total chlorophyll and 104.4% and 83.7% of carotenoid content,respectively.High soil arsenic amounts reduced the ratio of chlorophyll content at podding stage to that at grain filling stage significantly.In conclusion,high soil arsenic amounts are toxic to soybean growth,affect the allocarion of soybean biomass,and decrease the biomass of aerial parts and grains yield

  18. The effect of acid rain stress on chlorophyll, peroxidase of the conservation of rare earth elements

    International Nuclear Information System (INIS)

    Full text: Based on pot experiment, the effect of acid rain stress on chlorophyll, peroxidase of wheat, the relationship of them and the conservation of rare earth elements has been studied. The result showed: stress of acid rain resulted in decrease of chlorophyll content and a/b values, chlorophyll a/b value and chlorophyll content is positive correlation with pH value of acid rain: peroxidase activity was gradually rise with pH value decrease, which indirectly increased decomposition intensity of chlorophyll. Decreased content and a/b value of chlorophyll further speeded blade decay affected the transport and transformation of light energy and metabolism of carbohydrates. After being treated by rare earth elements content and pH value of chlorophyll and peroxidase activity could be relatively stable. Therefore, under lower acidity condition, rare earth elements can influence the effect of acid rain on chlorophyll and peroxidase activity of wheat

  19. Effects of different concentrations of nitrogen and phosphorus on chlorophyll biosynthesis,chlorophyll a fluorescence,and photosynthesis In Larix olgensis seedlings

    Institute of Scientific and Technical Information of China (English)

    Wu Chu; Wang Zhengquan; Sun Hailong; Guo Shenglei

    2006-01-01

    concentrations increased to 16 mmol/L,photosynthetic rate reduced by 16%,in contrast to the control.Photosynthetic rates reached a maximum when seedlings were supplied with 1 mmol/L,and an oversupply of phosphate (2 mmol/L)resulted in decrease in photosynthetic rates.The results suggested that supply levels of nitrogen affected ALA biosynthetic rates,activities of PBG synthase,and affected contents of chlorophyll and carotenoids.Moreover,nitrogen supply levels affected contents of total nitrogen and soluble proteins in leaves,and net photosynthetic rates.ALA biosynthesis rates and activities of PBG synthase were affected by phosphate supply,but contents of chlorophyll and carotenoids were not affected.And net photosynthetic rates were affected little by phosphate supply.

  20. Chlorophyll_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included chlorophyll for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came from...

  1. OSU Chlorophyll Bloom Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This product was developed for the Oregon coast based on the observed change between running 8-day composite chlorophyll-a (CHL) data obtained by the MODerate...

  2. Chlorophyll: The wonder pigment

    Digital Repository Service at National Institute of Oceanography (India)

    Bhat, S.R.

    juice or grow our own sprouts, instead we try to get the benefits of green foods through capsules, tablets or powder of dehydrated or freeze dried forms of wheat grass, blue green algae, or different cereal grasses. Chlorophyll or its derivative... vegetables rich in micronutrients are spinach, drum stick leaves, lettuce, cucumber, beans and green peas. SCIENCE REPORTER, July 2005 31 Feature Article Chlorophyll in Algae Amazingly, some freshwater and marine algae, yet to find place in our daily diet...

  3. Optofluidic chlorophyll lasers.

    Science.gov (United States)

    Chen, Yu-Cheng; Chen, Qiushu; Fan, Xudong

    2016-06-21

    Chlorophylls are essential for photosynthesis and also one of the most abundant pigments on earth. Using an optofluidic ring resonator of extremely high Q-factors (>10(7)), we investigated the unique characteristics and underlying mechanism of chlorophyll lasers. Chlorophyll lasers with dual lasing bands at 680 nm and 730 nm were observed for the first time in isolated chlorophyll a (Chla). Particularly, a laser at the 730 nm band was realized in 0.1 mM Chla with a lasing threshold of only 8 μJ mm(-2). Additionally, we observed lasing competition between the two lasing bands. The presence of laser emission at the 680 nm band can lead to quenching or significant reduction of laser emission at the 730 nm band, effectively increasing the lasing threshold for the 730 nm band. Further concentration-dependent studies, along with theoretical analysis, elucidated the mechanism that determines when and why the laser emission band appears at one of the two bands, or concomitantly at both bands. Finally, Chla was exploited as the donor in fluorescence resonance energy transfer to extend the laser emission to the near infrared regime with an unprecedented wavelength shift as large as 380 nm. Our work will open a door to the development of novel biocompatible and biodegradable chlorophyll-based lasers for various applications such as miniaturized tunable coherent light sources and in vitro/in vivo biosensing. It will also provide important insight into the chlorophyll fluorescence and photosynthesis processes inside plants. PMID:27220992

  4. Impact of salt stress (NaCl) on growth, chlorophyll content and fluorescence of Tunisian cultivars of chili pepper (Capsicum frutescens L.)

    OpenAIRE

    Kaouther Zhani; Ben Fredj Mariem; Mani Fardaous; Hannachi Cherif

    2012-01-01

    Salinity is considered as the most important abiotic stress limiting crop production and plants are known to be able continuing survive under this stress by involving many mechanisms. In this content, the present study was carried out to evaluate the impact of NaCl on some physiological and biochemical parameters in five Tunisian chili pepper (Capsicum frutescens L.) cultivars: Tebourba (Tb), Somaa (Sm), Korba (Kb), Awald Haffouzz (AW) and Souk jedid (Sj). Thus, an experiment of five months w...

  5. Quantifying mangrove chlorophyll from high spatial resolution imagery

    Science.gov (United States)

    Heenkenda, Muditha K.; Joyce, Karen E.; Maier, Stefan W.; de Bruin, Sytze

    2015-10-01

    Lower than expected chlorophyll concentration of a plant can directly limit photosynthetic activity, and resultant primary production. Low chlorophyll concentration may also indicate plant physiological stress. Compared to other terrestrial vegetation, mangrove chlorophyll variations are poorly understood. This study quantifies the spatial distribution of mangrove canopy chlorophyll variation using remotely sensed data and field samples over the Rapid Creek mangrove forest in Darwin, Australia. Mangrove leaf samples were collected and analyzed for chlorophyll content in the laboratory. Once the leaf area index (LAI) of sampled trees was estimated using the digital cover photography method, the canopy chlorophyll contents were calculated. Then, the nonlinear random forests regression algorithm was used to describe the relationship between canopy chlorophyll content and remotely sensed data (WorldView-2 satellite image bands and their spectral transformations), and to estimate the spatial distribution of canopy chlorophyll variation. The imagery was evaluated at full 2 m spatial resolution, as well as at decreased resampled resolutions of 5 m and 10 m. The root mean squared errors with validation samples were 0.82, 0.64 and 0.65 g/m2 for maps at 2 m, 5 m and 10 m spatial resolution respectively. The correlation coefficient was analyzed for the relationship between measured and predicted chlorophyll values. The highest correlation: 0.71 was observed at 5 m spatial resolution (R2 = 0.5). We therefore concluded that estimating mangrove chlorophyll content from remotely sensed data is possible using red, red-edge, NIR1 and NIR2 bands and their spectral transformations as predictors at 5 m spatial resolution.

  6. Salinity reduced growth PS2 photochemistry and chlorophyll content in radish Crescimento reduzido por salinidade, fotoquímica PS2 e conteúdo de clorofila em rabanete

    Directory of Open Access Journals (Sweden)

    Muhammad Jamil

    2007-01-01

    Full Text Available When plants are grown under saline conditions, photosynthetic activity decreases leading to reduced plant growth, leaf area, chlorophyll content and chlorophyll fluorescence. Seeds and seedlings of radish (Raphanus sativus L. were grown in NaCl solutions under controlled greenhouse conditions. The NaCl concentrations in complete nutrient solutions were 0 (control, 4.7, 9.4 and 14.1 dS m-1. The salinity reduced germination percentage and also delayed the germination rate as the salt level increased. Lengths and fresh weights of root and shoot decreased with the increasing salt concentration. Furthermore, photochemical efficiency of PS2 (Fv/Fm, photochemical quenching coefficient (qP, non photochemical quenching coefficient (qN, leaf area and chlorophyll content (SPAD value were also reduced (P Quando plantas crescem sob condições de salinidade, sua atividade fotossintética diminui levando a um crescimento reduzido, menor área foliar, conteúdo de clorofila e fluorescência de clorofila. Sementes e plântulas de rabanete (Raphanus sativus L. foram germinadas e conduzidas em soluções de NaCl sob condições controladas de casa de vegetação. As concentrações de NaCl adicionado a solução nutritiva completa foram 0 (Controle, 4,7; 9,4 e 14,1 dS m-1. A salinidade diminui a percentagem de germinação e também atrasou a taxa de germinação com o aumento do nível de sal. Comprimento e peso fresco da parte aérea e da raiz decresceram com o aumento da concentração salina. Além disso, a eficiência fotoquímica de PS2 (Fv/Fm, o coeficiente fotoquímico de 'quenchin" (q p, o coeficiente não fotoquímico de "quenching" (q n, a área foliar e o teor de clorofila (valor SPAD também foram reduzidos (P < 0,001 por estresse de sal. Ao contrário, a relação Fo/Fm aumentou com a concentração salina, ao passo que a salinidade não teve efeito sobre a eficiência de excitação capturada pelo PS2 aberto (Fv'/Fm', taxa de transporte eletr

  7. Bowel perforation detection using metabolic fluorescent chlorophylls

    Science.gov (United States)

    Han, Jung Hyun; Jo, Young Goun; Kim, Jung Chul; Choi, Sujeong; Kang, Hoonsoo; Kim, Yong-Chul; Hwang, In-Wook

    2016-03-01

    Thus far, there have been tries of detection of disease using fluorescent materials. We introduce the chlorophyll derivatives from food plants, which have longer-wavelength emissions (at >650 nm) than those of fluorescence of tissues and organs, for detection of bowel perforation. To figure out the possibility of fluorescence spectroscopy as a monitoring sensor of bowel perforation, fluorescence from organs of rodent models, intestinal and peritoneal fluids of rodent models and human were analyzed. In IVIS fluorescence image of rodent abdominal organ, visualization of perforated area only was possible when threshold of image is extremely finely controlled. Generally, both perforated area of bowel and normal bowel which filled with large amount of chlorophyll derivatives were visualized with fluorescence. The fluorescence from chlorophyll derivatives penetrated through the normal bowel wall makes difficult to distinguish perforation area from normal bowel with direct visualization of fluorescence. However, intestinal fluids containing chlorophyll derivatives from food contents can leak from perforation sites in situation of bowel perforation. It may show brighter and longer-wavelength regime emissions of chlorophyll derivatives than those of pure peritoneal fluid or bioorgans. Peritoneal fluid mixed with intestinal fluids show much brighter emissions in longer wavelength (at>650 nm) than those of pure peritoneal fluid. In addition, irrigation fluid, which is used for the cleansing of organ and peritoneal cavity, made of mixed intestinal and peritoneal fluid diluted with physiologic saline also can be monitored bowel perforation during surgery.

  8. Photosynthetic behavior, growth and essential oil production of Melissa officinalis L. cultivated under colored shade nets

    Directory of Open Access Journals (Sweden)

    Graziele C Oliveira

    2016-03-01

    Full Text Available The modulation of light is of importance during cultivation of medicinal plants to obtain desirable morphological and physiological changes associated with the maximum production of active principles. This study aimed to evaluate the effect of the light spectrum transmitted by colored shade nets on growth, essential oil production and photosynthetic behavior in plants of lemon balm (Melissa officinalis L. Plants were cultivated in pots for 4-mo under black, red, and blue nets with 50% shading, and full sunlight exposure. Biometric and anatomical variables, essential oil yield, global solar radiation, photon flux density, chlorophyll content, and gas exchange parameters were measured in M. officinalis leaves. The results showed that despite being considered a partial shade plant, this species is able to adapt to full sunlight conditions without increasing biomass production. The spectral changes provided by colored shade nets did not caused any noticeable change in leaf anatomy of M. officinalis. However, the use of blue net resulted in increments of 116% in plant height, 168% in leaf area, 42% in chlorophyll content and 30% in yield of essential oil in lemon balm plants. These plant's qualities make the use of blue net a cultivation practice suitable for commercial use.

  9. Pulse amplitude modulated chlorophyll fluorometer

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias; Wu, Jie

    2015-12-29

    Chlorophyll fluorometry may be used for detecting toxins in a sample because of changes in micro algae. A portable lab on a chip ("LOAC") based chlorophyll fluorometer may be used for toxin detection and environmental monitoring. In particular, the system may include a microfluidic pulse amplitude modulated ("PAM") chlorophyll fluorometer. The LOAC PAM chlorophyll fluorometer may analyze microalgae and cyanobacteria that grow naturally in source drinking water.

  10. As clorofilas The chlorophylls

    Directory of Open Access Journals (Sweden)

    Nivia Maria Streit

    2005-06-01

    Full Text Available As clorofilas são pigmentos verdes, comuns em todas as células fotossintéticas. Por sua estrutura química ser instável, são facilmente degradadas, resultando em produtos de decomposição que modificam a percepção e qualidade dos alimentos. Esta revisão trata dos vários fatores que interferem na degradação das clorofilas, como a luz, radiação, calor, ácidos, oxigênio, alteração enzimática e interação com outros pigmentos. Também, outro aspecto a ser abordado é a utilização das clorofilas como corantes, através da formação de complexos que tornam esses pigmentos mais estáveis à decomposição.The Chlorophylls are a common green pigment to all photosynthetic cells. They are easily degraded, because of their unstable chemical structure. Degradation results in products alter the perception and quality of foods. This review discusses the various factors, that interfere on chlorophyll degradation such as light, irradiation, heat, acids, oxygen, enzymatical alteration and the interaction with other pigments. Also, the other topic that was mentioned the utilization of the chlorophylls as dyes through a complex formation that make this pigment more stable to degradation.

  11. Evaluation of nitrogen status and total chlorophyll in longkong (Aglaia dookkoo Griff. leaves under water stress using a chlorophyll meter

    Directory of Open Access Journals (Sweden)

    Sdoodee, S.

    2005-07-01

    Full Text Available A chlorophyll meter (SPAD-502 was used to assess nitrogen status and total chlorophyll in longkong leaves, leaves from twelve of 10-year-old trees grown in the experimental plot at Prince of Songkla University, Songkhla province. The relationship between SPAD-502 meter reading and nitrogen status and total chlorophyll content analyzed in the laboratory was evaluated during 8 months (May-December 2003. It was found that the trend of the relationships in each month was similar. There was no significant differenceamong regression linears of all months. The data of 8 months showed that SPAD-reading and nitrogen content, and SPAD-reading and total chlorophyll content were related in a positive manner. They were Y = 0.19X+10.10, r = 0.76** (n = 240, and Y = 0.43X-7.89, r = 0.79** (n = 400, respectively. The SPAD-502 was then used to assess total nitrogen and total chlorophyll content during imposed water stress. Fifteen 4-yearold plants were grown in pots (each pot containing 50 kg soil volume. The experiment was arranged in acompletely randomized design with 3 treatments: (1 daily watering (2 once watering on day 7 (3 no watering with 5 replications during 14 days of the experimental period. Measurements showed a continuous decrease of SPAD-reading in the treatment of no watering. On day 14, a significant difference of SPAD- reading values between the treatment of daily watering and no watering was found. Then, the values of nitrogen content and total chlorophyll were assessed by using the linear regression equations. From the result, it is suggested that the measurement by chlorophyll meter is a rapid technique for the evaluation of total chlorophyll and nitrogen status in longkong leaves during water stress.

  12. Photosynthetic pigments content, photosynthesis rate and chloroplast structure in young plants of Mikania laevigata Schultz Bip. ex Baker grown under colored netsTeores de pigmentos fotossintéticos, taxa de fotossíntese e estrutura de cloroplastos de plantas jovens de Mikania laevigata Schultz Bip. ex Baker cultivadas sob malhas coloridas

    Directory of Open Access Journals (Sweden)

    Anacleto Ranulfo dos Santos

    2011-12-01

    Full Text Available Guaco (Mikania laevigata is a medicinal plant used to treat fever, rheumatism, flu and respiratory tract diseases. Understanding the physiology of this species and its responses to environmental conditions has become necessary to improving the cultivation methods. In this context, this work aimed to access the effects of shading by using colored nets in on photosynthetic pigment concentration, photosynthetic rate and ultrastructure of chloroplasts of Mikania laevigata. The plants were cultivated during four months under nets with 50% shading in blue, red and gray color nets and under full sunlight (0%. The plants grown under full sunlight had decreased contents of a and b chlorophyll, and of carotenoids, while those grown under blue nets shown higher concentrations of a and b chlorophyll. The lowest density of chloroplasts was found in plants cultivated under full sunlight. Elongated chloroplasts were noticed in treatments with 50% shading. Regarding the potential rate of photosynthesis no significant change was observed among the plants grown under red, blue and gray nets, which leads to the conclusion that the spectrum transmitted by different coloured nets did not affect guaco photosynthetic apparatus.O guaco (Mikania laevigata é uma planta medicinal, usada para o tratamento de febre, reumatismo, gripe e doenças do trato respiratório. O entendimento do comportamento fisiológico dessa espécie e as suas respostas às condições do ambiente tornam-se necessários ao aperfeiçoamento dos métodos de cultivo. Nesse contexto, o presente trabalho teve como objetivo avaliar os efeitos do sombreamento com uso de malhas coloridas na concentração de pigmentos fotossintéticos, na taxa de fotossíntese e na ultra-estrutura de cloroplastos de plantas de Mikania laevigata. As plantas foram cultivadas por quatro meses sob malhas de 50% de sombreamento nas cores azul, vermelha e cinza e a pleno sol (0%. As plantas mantidas a pleno sol tiveram os

  13. Effects of External Coloured Shade Nets on Sweet Peppers Cultivated in Walk-in Plastic Tunnels

    Directory of Open Access Journals (Sweden)

    Attila OMBÓDI

    2015-12-01

    Full Text Available Shading effect of external nets of different colours (white, green, yellow and red on the yield of two “kapija” pepper (Capsicum anuum L. cultivars was examined in walk-in plastic tunnels in Hungary under real cultivation circumstances. Shading nets decreased incoming radiation by 23-39% and reduced photosynthetically active radiation by 32-46%. The highest retention was obtained by yellow and green nets, in the range of 450-550 nm and 550-670 nm, respectively. Relation was reported between the degree of shading and the average air temperature of the tunnels, however, treatments did not decrease tunnel air temperature significantly, compared to that of unshaded and paint-shaded control tunnels. This can be explained by the applied proper ventilation and mist irrigation. A strong and negative relation was noted between the intensity of shading and the relative chlorophyll content (SPAD value of leaves. Shading net treatments did not increase yields, yellow and green nets even decreased it. Instead of tunnel air temperature, yield was mainly affected by photosynthetically active radiation in the experiment. Strong positive linear relation was declared between the chlorophyll content of the leaves and the yield. Results of the current research led to the conclusions that under Hungarian climatic conditions the use of shading nets was less justified if proper cooling techniques (ventilation and mist irrigation were applied; even under the relatively high incident radiation experienced during the trials. In greenhouses of less favourable climatic conditions, red or white shading nets are recommended instead of commonly used green ones in Hungary.

  14. Temperature, salinity, transmissivity, pressure, plankton, oxygen, nutrients, chlorophyll, and primary productivity data collected using CTD, bottle, and plankton net from the R/V Italica in the Ross Sea and Magellan Strait during 10th Italian Antarctic Expedition from 1994-11-13 to 1995-04-02 (NCEI Accession 0068289)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, salinity, transmissivity, pressure, plankton, oxygen, nutrients, chlorophyll, and primary productivity data collected using CTD, bottle, and plankton...

  15. Chlorophyll d: the puzzle resolved

    DEFF Research Database (Denmark)

    Larkum, Anthony W D; Kühl, Michael

    2005-01-01

    Chlorophyll a (Chl a) has always been regarded as the sole chlorophyll with a role in photochemical conversion in oxygen-evolving phototrophs, whereas chlorophyll d (Chl d), discovered in small quantities in red algae in 1943, was often regarded as an artefact of isolation. Now, as a result of...... discoveries over the past year, it has become clear that Chl d is the major chlorophyll of a free-living and widely distributed cyanobacterium that lives in light environments depleted in visible light and enhanced in infrared radiation. Moreover, Chl d not only has a light-harvesting role but might also...... replace Chl a in the special pair of chlorophylls in both reactions centers of photosynthesis. Udgivelsesdato: 2005-Aug...

  16. Improvement of the Measurement of the Net Content of Grand Packing Liquor Products%大包装白酒产品净含量测量方法的探讨与改进

    Institute of Scientific and Technical Information of China (English)

    刘淑玲; 李建刚

    2012-01-01

    用绝对体积法测量白酒产品的净含量时,由于挂壁、标准量器的精确度低,使得检验不准确,特别是对于大包装产品,随着测量次数的增多,测量误差更进一步扩大。不同温度下,白酒的净含量会发生变化,即净含量随温度的升高而增加,随温度的降低而减少,但白酒质量不受温度的影响。称重法是测量大包装白酒产品净含量的最佳选择。%The measurement of the net content of liquor products by absolute volume method has inaccurate results due to the low accuracy of hanging wall and standard gauges,especially in the measurement of the net content of grand packing liquor products,increasing measurement times would further expand such measurement errors.As we know,liquor net content changes under different temperature,increasing with temperature rise and decreasing with temperature drop,however,liquor quality is hardly influenced by temperature.In practice,weighing method is the best choice in the measurement of the net content of grand packing liquor products.

  17. Technical note: precision and accuracy of in vitro digestion of neutral detergent fiber and predicted net energy of lactation content of fibrous feeds.

    Science.gov (United States)

    Spanghero, M; Berzaghi, P; Fortina, R; Masoero, F; Rapetti, L; Zanfi, C; Tassone, S; Gallo, A; Colombini, S; Ferlito, J C

    2010-10-01

    The objective of this study was to test the precision and agreement with in situ data (accuracy) of neutral detergent fiber degradability (NDFD) obtained with the rotating jar in vitro system (Daisy(II) incubator, Ankom Technology, Fairport, NY). Moreover, the precision of the chemical assays requested by the National Research Council (2001) for feed energy calculations and the estimated net energy of lactation contents were evaluated. Precision was measured as standard deviation (SD) of reproducibility (S(R)) and repeatability (S(r)) (between- and within-laboratory variability, respectively), which were expressed as coefficients of variation (SD/mean × 100, S(R) and S(r), respectively). Ten fibrous feed samples (alfalfa dehydrated, alfalfa hay, corn cob, corn silage, distillers grains, meadow hay, ryegrass hay, soy hulls, wheat bran, and wheat straw) were analyzed by 5 laboratories. Analyses of dry matter (DM), ash, crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) had satisfactory S(r), from 0.4 to 2.9%, and S(R), from 0.7 to 6.2%, with the exception of ether extract (EE) and CP bound to NDF or ADF. Extending the fermentation time from 30 to 48 h increased the NDFD values (from 42 to 54% on average across all tested feeds) and improved the NDFD precision, in terms of both S(r) (12 and 7% for 30 and 48 h, respectively) and S(R) (17 and 10% for 30 and 48 h, respectively). The net energy for lactation (NE(L)) predicted from 48-h incubation NDFD data approximated well the tabulated National Research Council (2001) values for several feeds, and the improvement in NDFD precision given by longer incubations (48 vs. 30 h) also improved precision of the NE(L) estimates from 11 to 8%. Data obtained from the rotating jar in vitro technique compared well with in situ data. In conclusion, the adoption of a 48-h period of incubation improves repeatability and reproducibility of NDFD and accuracy and reproducibility of the associated calculated

  18. Influence of UV-B radiation on photosynthetic activity and chlorophyll fluorescence kinetics in Norway spruce (Picea abies (L.) Karst.) seedlings

    International Nuclear Information System (INIS)

    Norway spruce [Picea abies (L.) Karst.] seedlings were grown in greenhouses with two supplemental levels of ultraviolet-B (UV-B) radiation. Photochemical efficiency of photosystem II and vitality index were determined monthly. At the end of the experiment, growth, chlorophyll content and photosynthetic rates were measured. The data indicate that low temperature in winter affected light dependent processes in experimental plants including control, while the rise of ambient temperatures, moderate this effect. The synergistic effects of UV-B radiation and low temperatures could only be observed in the second winter period. Measurements of net photosynthetic activity in the second winter period showed significant differences between treated and untreated plants. (author)

  19. Effect of different concentrations of potassium silicate, nano-silicon and calcium chloride on concentration of potassium, calcium and magnesium, chlorophyll content and number of florets of Asiatic lily cv. ‘Brunello’

    OpenAIRE

    N. Mirabbasi; A. Nikbakht; N. Etemadi; M.R. Sabzalian

    2013-01-01

    Production of many cut flowers, such as lilium, is very common in Iran. Flower quality has special importance in lilium flower production process, and proper nutrition is one of the major effective factors. This research was conducted to investigate the effect of different concentrations of potassium silicate, nano-silicon and calcium chloride on concentration of potassium, calcium and magnesium, chlorophyll index and number of florets of Asiatic lily 'Brunello'. The experiment was carried ou...

  20. Content

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    Aim, content and methods are fundamental categories of both theoretical and practical general didactics. A quick glance in recent pedagogical literature on higher education, however, reveals a strong preoccupation with methods, i.e. how teaching should be organized socially (Biggs & Tang, 2007; R...... strategy is theoretically based on systems theory as formulated by Niklas Luhmann (Luhmann, 1995; 2002) and on own work, where. Luhmann’s general ideas and concepts of the educational system are transposed into a didactical framework (Keiding, 2005,2007,2008).......Aim, content and methods are fundamental categories of both theoretical and practical general didactics. A quick glance in recent pedagogical literature on higher education, however, reveals a strong preoccupation with methods, i.e. how teaching should be organized socially (Biggs & Tang, 2007......, is subordinating content to methods as seen in modern didactics, hereby transforming content to a medium for achievement of learning-to-learn skills rather than something valuable in its own right. At the level of general didactics quite few attempts have been made to formulate criteria and...

  1. Study of 660 nm laser-induced photoluminescence of chlorophyll-a and its applications

    International Nuclear Information System (INIS)

    Based on the phenomenon of chlorophyll a photoluminescence, this paper introduces a new method to measure the chlorophyll a content, using 660nm laser diode as a new kind of light source to stimulate fluorescence as well as combining a fiber and spectrum technique. We analyze the characteristics of laser-induced fluorescence spectrum of chlorophyll a and then put forward the new method using two parameters, the relative fluorescence intensity and fluorescence intensity ratio F685/F735, to measure the chlorophyll a content in the water and green leaves respectively. The experimental results indicate that it is completely feasible to give a visual judgment for chlorophyll a content, according to the fluorescence emission spectrum of chlorophyll a. Subsequently, it is verified by three kinds of typical applications. All of these provide a new kind of light source to develop the chlorophyll a fluorometry and further give a technical foundation of on-spot monitoring the chlorophyll a content in the ocean or in green leaves

  2. Investigating the impact of NaCl salinity on growth, β-carotene, and chlorophyll a in the content life of halophytes of algae Chlorella sp.

    OpenAIRE

    Mojtaba Fathi; Alireza Asem

    2013-01-01

    Algae are used for many purposes as: food industry, animal feeding, soil enrichment andbiodiesel production. Chlorella is widely cultivated from microalgae species as it is rich in nutrients andhas its implementation as a healthy food use. In this study, the impact of NaCl salinity on growth, betacarotene,and chlorophyll a of Chlorella sp. has been investigated. This study results in three salinities(10, 30, 50 g L-1, respectively) have shown that 30 g L-1 concentration has the highest value ...

  3. Mechanism of lanthanum effect on chlorophyll of spinach

    Institute of Scientific and Technical Information of China (English)

    洪法水; 魏正贵; 赵贵文

    2002-01-01

    The mechanism of La3+ effect on chlorophyll (chl) of spinach in solution culture has been studied. The results show that La3+ can obviously promote growth, increase chlorophyll contents and photosynthetic rate of spinach. La3+ may substitute Mg2+ for chlorophyll formation of spinach when there is no Mg2+ in solution. La3+ improves significantly PSII formation and enhances electron transport rate of PSII. By ICP-MS and atom absorption spectroscopy methods, it has been revealed that rare earth elements (REEs) can enter chloroplasts and increase Mg2+-chl contents; and REEs bind to chlorophyll and also form REE-chl. REE-chl is about 72% in total chlorophyll with La3+ treatment and without Mg2+ in solution. By UV-Vis, FT-IR and extended X-ray absorption fine structure spectroscopy (EXAFS) methods, it has been found that La3+ coordinates with nitrogen of porphyrin rings with the average La-N bond length of 0.253 nm.

  4. DUF538 protein superfamily is predicted to be chlorophyll hydrolyzing enzymes in plants.

    Science.gov (United States)

    Gholizadeh, Ashraf

    2016-01-01

    The possible hydrolytic activity towards chlorophyll molecules was predicted for DUF538 protein superfamily in plants. It was examined by using computational as well as experimental tools including in vitro chlorophyll degradation, antioxidant compounds production and in vivo real-time gene expression tests. Comparison of the computational data with the experimental results indicated that DUF538 proteins might be chlorophyll hydrolyzing enzyme (most probably carboxyesterase) which degrade chlorophyll molecules (66 % per 12 hrs) to produce new compounds (1.8 fold per 12 hrs) with antioxidant properties. The relevance of DUF538 gene expression level with the chlorophyll contents (2.8 fold increase per chlorophyll content of 50 %) of the drought-stressed leaves showed that chlorophyll degradation by DUF538 is most probably induced in response to stress stimuli. Despite membranous chlorophyll catabolic pathways, DUF538-dependent reactions is predicted to be occurred in the cytosol of the under stressed plants. We addressed as to whether chlorophyll breakdown to antioxidant compounds by DUF538 is a defense mechanism of plants against stress stimuli, in vivo? This question is going to be investigated in our next research project. PMID:27186021

  5. Mahalanobis distance screening of Arabidopsis mutants with chlorophyll fluorescence

    Czech Academy of Sciences Publication Activity Database

    Codrea, C. C.; Hakala-Yatkin, M.; Karlund-Marttila, A.; Nedbal, Ladislav; Aittokallio, T.; Nevalainen, O. S.; Tyystjärvi, E.

    2010-01-01

    Roč. 105, č. 3 (2010), s. 273-283. ISSN 0166-8595 Institutional research plan: CEZ:AV0Z60870520 Keywords : arabidopsis thaliana * chlorophyll fluorescence * fluorescence imaging * mutant detection * outlier detection Subject RIV: EH - Ecology, Behaviour Impact factor: 2.410, year: 2010 http://www.springerlink.com/content/x3586512462pn006/

  6. CONTENTS

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The Development and Evolution of the Idea of the Mandate of Heaven in the Zhou Dynasty The changes in the idea of Mandate of Heaven during the Shang and Zhou dynasties are of great significance in the course of the development of traditional Chinese culture. The quickening and awakening of the humanistic spirit was not the entire content of the Zhou idea of Mandate of Heaven. In the process of annihilating the Shang dynasty and setting up their state, the Zhou propagated the idea of the Mandate of Heaven out of practical needs. Their idea of the Mandate of Heaven was not very different from that of the Shang. From the Western Zhou on, the Zhou idea of Mandate of Heaven by no means developed in a linear way along a rational track. The intermingling of rationality and irrationality and of awakening and non-awakening remained the overall state of the Zhou intellectual superstructure after their "spiritual awakening".

  7. Optimal leaf positions for chlorophyll meter measurement in rice

    Directory of Open Access Journals (Sweden)

    Zhaofeng eYuan

    2016-05-01

    Full Text Available The Soil Plant Analysis Development (SPAD chlorophyll meter is one of the most commonly used diagnostic tools to measure crop nitrogen status. However, the measurement method of the meter could significantly affect the accuracy of the final estimation. Thus, this research was undertaken to develop a new methodology to optimize SPAD meter measurements in rice (Oryza sativa L.. A flatbed color scanner was used to map the dynamic chlorophyll distribution and irregular leaf shapes. Calculus algorithm was adopted to estimate the potential positions for SPAD meter measurement along the leaf blade. Data generated by the flatbed color scanner and SPAD meter were analysed simultaneously. The results suggested that a position 2/3 of the distance from the leaf base to the apex (2/3 position could represent the chlorophyll content of the entire leaf blade, as indicated by the relatively low variance of measurements at that positon. SPAD values based on di-positional leaves and the extracted chlorophyll a and b contents were compared. This comparison showed that the 2/3 position on the lower leaves tended to be more sensitive to changes in chlorophyll content. Finally, the 2/3 position and average SPAD values of the fourth fully expanded leaf from the top were compared with leaf nitrogen concentration. The results showed the 2/3 position on that leaf was most suitable for predicting the nitrogen status of rice. Based on these results, we recommend making SPAD measurements at the 2/3 position on the fourth fully expanded leaf from the top. The coupling of dynamic chlorophyll distribution and irregular leaf shapes information can provide a promising approach for the calibration of SPAD meter measurement, which can further benefit the in situ nitrogen management by providing reliable estimation of crops nitrogen nutrition status.

  8. Net Locality

    DEFF Research Database (Denmark)

    de Souza e Silva, Adriana Araujo; Gordon, Eric

    Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps, to...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....

  9. Differential effects of glyphosate and aminomethylphosphonic acid (AMPA) on photosynthesis and chlorophyll metabolism in willow plants.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Le Manac'h, Sarah Gingras; Maccario, Sophie; Labrecque, Michel; Lucotte, Marc; Juneau, Philippe

    2016-06-01

    We used a willow species (Salix miyabeana cultivar SX64) to examine the differential secondary-effects of glyphosate and aminomethylphosphonic acid (AMPA), the principal glyphosate by-product, on chlorophyll metabolism and photosynthesis. Willow plants were treated with different concentrations of glyphosate (equivalent to 0, 1.4, 2.1 and 2.8kgha(-1)) and AMPA (equivalent to 0, 0.28, 1.4 and 2.8kgha(-1)) and evaluations of pigment contents, chlorophyll fluorescence, and oxidative stress markers (hydrogen peroxide content and antioxidant enzyme activities) in leaves were performed after 12h of exposure. We observed that AMPA and glyphosate trigger different mechanisms leading to decreases in chlorophyll content and photosynthesis rates in willow plants. Both chemicals induced ROS accumulation in willow leaves although only glyphosate-induced oxidative damage through lipid peroxidation. By disturbing chlorophyll biosynthesis, AMPA induced decreases in chlorophyll contents, with consequent effects on photosynthesis. With glyphosate, ROS increases were higher than the ROS-sensitive threshold, provoking chlorophyll degradation (as seen by pheophytin accumulation) and invariable decreases in photosynthesis. Peroxide accumulation in both AMPA and glyphosate-treated plants was due to the inhibition of antioxidant enzyme activities. The different effects of glyphosate on chlorophyll contents and photosynthesis as described in the literature may be due to various glyphosate:AMPA ratios in those plants. PMID:27155486

  10. Contents

    Directory of Open Access Journals (Sweden)

    Editor IJRED

    2012-11-01

    Full Text Available International Journal of Renewable Energy Development www.ijred.com Volume 1             Number 3            October 2012                ISSN 2252- 4940   CONTENTS OF ARTICLES page Design and Economic Analysis of a Photovoltaic System: A Case Study 65-73 C.O.C. Oko , E.O. Diemuodeke, N.F. Omunakwe, and E. Nnamdi     Development of Formaldehyde Adsorption using Modified Activated Carbon – A Review 75-80 W.D.P Rengga , M. Sudibandriyo and M. Nasikin     Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC 81-86 A. Buasri , B. Ksapabutr, M. Panapoy and N. Chaiyut     Wind Resource Assessment in Abadan Airport in Iran 87-97 Mojtaba Nedaei       The Energy Processing by Power Electronics and its Impact on Power Quality 99-105 J. E. Rocha and B. W. D. C. Sanchez       First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration 107-113 A. Merzic , M. Music, and M. Rascic   Experimental Study on the Production of Karanja Oil Methyl Ester and Its Effect on Diesel Engine 115-122 N. Shrivastava,  , S.N. Varma and M. Pandey  

  11. Chlorophylls, Symmetry, Chirality, and Photosynthesis

    Directory of Open Access Journals (Sweden)

    Mathias O. Senge

    2014-09-01

    Full Text Available Chlorophylls are a fundamental class of tetrapyrroles and function as the central reaction center, accessory and photoprotective pigments in photosynthesis. Their unique individual photochemical properties are a consequence of the tetrapyrrole macrocycle, the structural chemistry and coordination behavior of the phytochlorin system, and specific substituent pattern. They achieve their full potential in solar energy conversion by working in concert in highly complex, supramolecular structures such as the reaction centers and light-harvesting complexes of photobiology. The biochemical function of these structures depends on the controlled interplay of structural and functional principles of the apoprotein and pigment cofactors. Chlorophylls and bacteriochlorophylls are optically active molecules with several chiral centers, which are necessary for their natural biological function and the assembly of their supramolecular complexes. However, in many cases the exact role of chromophore stereochemistry in the biological context is unknown. This review gives an overview of chlorophyll research in terms of basic function, biosynthesis and their functional and structural role in photosynthesis. It highlights aspects of chirality and symmetry of chlorophylls to elicit further interest in their role in nature.

  12. Chlorophylls, Symmetry, Chirality, and Photosynthesis.

    OpenAIRE

    Mathias O. Senge; Aoife A. Ryan; Kristie A. Letchford; Stuart A. MacGowan; Tamara Mielke

    2014-01-01

    Chlorophylls are a fundamental class of tetrapyrroles and function as the central reaction center, accessory and photoprotective pigments in photosynthesis. Their unique individual photochemical properties are a consequence of the tetrapyrrole macrocycle, the structural chemistry and coordination behavior of the phytochlorin system, and specific substituent pattern. They achieve their full potential in solar energy conversion by working in concert in highly complex, supramolecular structures ...

  13. RESTful NET

    CERN Document Server

    Flanders, Jon

    2008-01-01

    RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

  14. Pb、Zn 及其交互作用对蜈蚣草抗氧化酶及叶绿素含量的影响∗%Effect of Pb and Zn interaction on antioxidant enzymes and chlorophyll content of Pteris vittata

    Institute of Scientific and Technical Information of China (English)

    夏红霞; 朱启红∗∗

    2013-01-01

    The effect of Pb and Zn interaction on antioxidant enzymes and chlorophyll content in Pteris vittata were evaluated by the nutrient solution culture experiments. The results showed that when Pb concentration was between 0—50 mg·L - 1 , chlorophyll content of Pteris vittata gradually increased and MDA content decreased with increasing Zn concentrations. Pb and Zn interaction promoted the synthesis of chlorophyll. When the Pb concentration was between 100—400 mg·L - 1 , Pb and Zn interaction decreased chlorophyll content. When the Pb concentration was 400 mg·L - 1 , the interaction increased MDA content significantly. The experimental results also showed that when Pb concentration was fixed, SOD and CAT activities in Pteris vittata increased first and then decreased with increasing Zn concentrations, and POD activity increased continuously. When Zn concentration was fixed, SOD,CAT and POD activities increased first and then decreased with increasing Pb concentration. It can be seen that at low Pb and Zn concentrations, their interaction presented synergistic, while at high concentrations,they showed antagonistic effect.%  采用水培实验的方法,研究了 Pb、Zn 及其交互作用对蜈蚣草抗氧化酶及叶绿素含量的影响。实验结果显示,Pb 浓度在0—50 mg·L -1时,蜈蚣草叶绿素含量随 Zn 浓度增加逐渐升高、MDA 含量逐渐降低,Pb、Zn交互作用可促进植株叶绿素合成。 Pb 浓度在100—400 mg·L -1时,Pb、Zn 交互作用则降低叶绿素含量;在 Pb浓度400 mg·L -1时,Pb、Zn 交互作用显著增加 MDA 含量。实验结果还显示,在 Pb 浓度固定时,蜈蚣草叶片SOD、CAT 的活性随 Zn 浓度增加呈现先上升后下降的趋势;POD 随着 Zn 处理浓度的增加持续增加。在 Zn 浓度一定时,蜈蚣草叶片 SOD、CAT、POD 的活性随 Pb 浓度增加先上升后下降。由此可见,在低 Pb、Zn 浓度下, Pb、Zn 交互作用表现为协同作用;在高 Pb、Zn

  15. Nondestructive and intuitive determination of circadian chlorophyll rhythms in soybean leaves using multispectral imaging

    Science.gov (United States)

    Pan, Wen-Juan; Wang, Xia; Deng, Yong-Ren; Li, Jia-Hang; Chen, Wei; Chiang, John Y.; Yang, Jian-Bo; Zheng, Lei

    2015-06-01

    The circadian clock, synchronized by daily cyclic environmental cues, regulates diverse aspects of plant growth and development and increases plant fitness. Even though much is known regarding the molecular mechanism of circadian clock, it remains challenging to quantify the temporal variation of major photosynthesis products as well as their metabolic output in higher plants in a real-time, nondestructive and intuitive manner. In order to reveal the spatial-temporal scenarios of photosynthesis and yield formation regulated by circadian clock, multispectral imaging technique has been employed for nondestructive determination of circadian chlorophyll rhythms in soybean leaves. By utilizing partial least square regression analysis, the determination coefficients R2, 0.9483 for chlorophyll a and 0.8906 for chlorophyll b, were reached, respectively. The predicted chlorophyll contents extracted from multispectral data showed an approximately 24-h rhythm which could be entrained by external light conditions, consistent with the chlorophyll contents measured by chemical analyses. Visualization of chlorophyll map in each pixel offers an effective way to analyse spatial-temporal distribution of chlorophyll. Our results revealed the potentiality of multispectral imaging as a feasible nondestructive universal assay for examining clock function and robustness, as well as monitoring chlorophyll a and b and other biochemical components in plants.

  16. Water chlorophyll-a retrieval index based on hyperspectral data%基于高光谱数据的水体叶绿素a指数反演模型的建立

    Institute of Scientific and Technical Information of China (English)

    王金梁; 秦其明; 李军; 林丛; 徐若风; 高中灵

    2014-01-01

    in July 2012 in the Lijiang River, Guangxi Zhuang Autonomous Region. The MTCI was based on the fast climbing vegetation reflectance in 680-750 nm also called the “red edge.” The MTCI was easy to calculate, and had a strong correlation with leaf chlorophyll-a content. From the beginning of 2004, the MTCI has became the core algorithm of the land chlorophyll-a product on ESA Envisat satellite’s MERIS sensor. This index is now widely used in land leaf chlorophyll-a retrival and net primary productivity (NPP) estimation. The WCI index also uses the different ratio of characteristic bands to represent the water chlorophyll-a content. The WCI index uses hyperspectral water reflectance at 650, 685, and 696 nm. We used the traditional method at the same location to verify all these models’s effect. The traditional methods consist of the reflectance model, reflectance ratio model, and the semi-analytical model (three bands model). The three traditional methods directly selected the water spectral reflectance at certain bands. Spectral smoothing can reduce the band noise at certain extent, but is easy to select the wrong band for the measured hyperspectral data because the absorption and reflection peak of water spectrum has big differences in different water spectrum curves. Our research also moticed that the change information of water spectrum was more useful compared with the water spectrum itself. Our results indicated that the new WCI index showed the best coefficient of determination 0.58 and the least RMSE 0.24 compared with the reflectance model, reflectance ratio model, and semi-analytical model. The test results also showed that the WCI model can retrieve the water chlorophyll-a content effectively at Tianjin City Haihe River. This method extended the idea of water chlorophyll-a content modeling from the view of the terrestrial vegetation chlorophyll-a monitoring, and has certain instructive effect on water chlorophyll-a content monitoring. More situ data of

  17. Effect of PEG-6000 Imposed Water Deficit on Chlorophyll Metabolism in Maize Leaves

    Directory of Open Access Journals (Sweden)

    Rekha Gadre

    2013-08-01

    Full Text Available Drought stress is one of the major abiotic constraint limiting plant growth and productivity world wide. The current study was undertaken with the aim to investigate the effect of water deficit imposed by PEG-6000, on chlorophyll metabolism in maize leaves to work out the mechanistic details. Leaf segments prepared from primary leaves of etiolated maize seedlings were treated with varying concentrations of polyethylene glycol-6000 (PEG-6000; w/v- 5%, 10%, 20%, 30% in continuous light of intensity 40 Wm-2 at 26±2 °C for 24 h in light chamber. The results demonstrate a concentration dependent decline in chlorophyll content with increasing concentration of polyethylene glycol-6000 (PEG-6000. Reduction in chlorophyll ‘a’ level was to a greater extent than the chlorophyll ‘b’. The RNA content decreased in a concentration dependent manner with PEG, however, proline content increased significantly. Relative water content decreased significantly with the supply of 30% PEG only. A substantial decrease in chlorophyll synthesis due to significant reduction in ALA content and ALAD activity, with no change in chlorophyllase activity with the supply of PEG suggests that water deficit affects chlorophyll formation rather than its degradation.

  18. Chlorophyll and carbohydrates in Arachis pintoi plants under influence of water regimes and nitrogen fertilization

    Directory of Open Access Journals (Sweden)

    Rita Manuele Porto Sales

    2013-06-01

    Full Text Available In this experiment the chlorophyll and carbohydrate contents of Arachis pintoi were evaluated to verify if the presence of nitrogen in the soil could contribute to the effectiveness of the establishment of this legume. The design was completely randomized, in a 4 × 4 factorial arrangement, with four N rates (0, 40, 80 and 120 kg ha-1 and four irrigation levels (25, 50, 75 and 100% of field capacity, with four replications. The biochemical evaluations of chlorophylls a and b and total chlorophyll and total soluble sugars, sucrose and starch were performed. The highest contents of chlorophyll a and b and total chlorophyll in leaves were found at the dose of 120 kg ha-1. The water regime of 25% of field capacity was responsible for the lowest content of reducing sugars and total soluble sugars in leaves, stolons and roots. In the roots, the sucrose contents were higher in these conditions, which can be associated with a slight tolerance of the plant to water stress. The water deficiency was responsible for the decrease of reducing sugars and total N in the whole plant and positively influenced the levels of chlorophyll and sugars in the stolon, promoting growth, especially of shoots, at the beginning of establishment.

  19. Crescimento, teor e composição do óleo essencial de melissa cultivada sob malhas fotoconversoras Growth, content and composition of lemon balm essential oil cultivated under color shading nets

    Directory of Open Access Journals (Sweden)

    Renata da Silva Brant

    2009-08-01

    Full Text Available A utilização de malhas fotoconversoras para o cultivo de algumas espécies ornamentais e olerícolas tornou-se comum. Diante da grande influência que a radiação solar exerce sobre os vegetais, esta pesquisa foi realizada com o objetivo de avaliar o efeito da intensidade e da qualidade espectral da luz transmitida pelas malhas fotoconversoras (Chromatinet® em relação a aspectos fisiológicos de crescimento (teor, rendimento e composição química do óleo essencial de Melissa officinalis L. Em delineamento inteiramente casualizado, foram dispostos quatro tratamentos e cinco repetições, sendo cada parcela composta de quatro vasos (uma planta por vaso. Os tratamentos foram caracterizados por plantas de melissa cultivadas a pleno sol, em malha preta (50%, em malha Chromatinet® vermelha (50% e em Chromatinet® azul (50%. As características avaliadas consistiram em: fitomassa seca de folhas, caules, parte aérea, raízes e total; razão raiz/parte aérea; área foliar total; razão de área foliar; razão de peso foliar; área foliar específica; teor, rendimento e composição química do óleo essencial. A utilização de malhas no cultivo de melissa favoreceu o crescimento, independentemente da cor, em relação ao cultivo a pleno sol. Sob a malha vermelha houve menores teor e rendimento óleo essencial, porém apresentou o maior teor de citral.The use of color shading nets for cultivation of some ornamentals and vegetables has become common. Thus, observing the great influence of the solar radiation on the plant physiology, the objective of this research was to evaluate the the quantity and quality effects of spectral light transmitted through color shading nets (Chromatinet® in Melissa officinalis L., including physiological aspects as:growth ,content and chemistry composition. Four treatments and five replications were disposed in a completely randomized design, being each experimental unit composed by four pots (one plant per pot

  20. Efficiency of chlorophyll in gross primary productivity: A proof of concept and application in crops.

    Science.gov (United States)

    Gitelson, Anatoly A; Peng, Yi; Viña, Andrés; Arkebauer, Timothy; Schepers, James S

    2016-08-20

    One of the main factors affecting vegetation productivity is absorbed light, which is largely governed by chlorophyll. In this paper, we introduce the concept of chlorophyll efficiency, representing the amount of gross primary production per unit of canopy chlorophyll content (Chl) and incident PAR. We analyzed chlorophyll efficiency in two contrasting crops (soybean and maize). Given that they have different photosynthetic pathways (C3 vs. C4), leaf structures (dicot vs. monocot) and canopy architectures (a heliotrophic leaf angle distribution vs. a spherical leaf angle distribution), they cover a large spectrum of biophysical conditions. Our results show that chlorophyll efficiency in primary productivity is highly variable and responds to various physiological and phenological conditions, and water availability. Since Chl is accessible through non-destructive, remotely sensed techniques, the use of chlorophyll efficiency for modeling and monitoring plant optimization patterns is practical at different scales (e.g., leaf, canopy) and under widely-varying environmental conditions. Through this analysis, we directly related a functional characteristic, gross primary production with a structural characteristic, canopy chlorophyll content. Understanding the efficiency of the structural characteristic is of great interest as it allows explaining functional components of the plant system. PMID:27374843

  1. Effect of changes in chlorophyll concentration on photosynthetic properties I. Fluorescence and absorption of greening bean leaves

    NARCIS (Netherlands)

    Goedheer, J.C.

    1961-01-01

    In order to obtain new information about the way of functioning of chlorophyll in vivo a study was made of optical properties and photosynthesis under condition of a low chlorophyll content in the leave. It was found that the fluorescence yeild of greening bean leaves decreased from a value approxim

  2. Impact of petrochemicals on the photosynthesis of Halophila ovalis using chlorophyll fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Ralph, P.J.; Burchett, M.D. [University of Sydney (Australia). Institute for Coastal Resource Management and Dept. of of Environmental Biology and Horticulture

    1998-06-01

    Laboratory-cultured Halophila ovalis showed tolerance to petrochemical exposure up to 1% (w/v) solution of Bass Strait crude oil, an oil dispersant (Corexit 9527) and a mixture of crude oil and dispersant. Quantum yield, as measured by chlorophyll fluorescence, was the most sensitive measure of the photosynthetic processes affected by petrochemical. The results indicated clearly that chlorophyll fluorescence was effective at monitoring the onset and development of stress and recovery of H. ovalis when exposed to crude oil, dispersant and a mixture of the two compounds. Photosynthetic pigment content generally confirmed the chlorophyll fluorescence response; however, several anomalies occurred. (author)

  3. Impact of petrochemicals on the photosynthesis of Halophila ovalis using chlorophyll fluorescence

    International Nuclear Information System (INIS)

    Laboratory-cultured Halophila ovalis showed tolerance to petrochemical exposure up to 1% (w/v) solution of Bass Strait crude oil, an oil dispersant (Corexit 9527) and a mixture of crude oil and dispersant. Quantum yield, as measured by chlorophyll fluorescence, was the most sensitive measure of the photosynthetic processes affected by petrochemical. The results indicated clearly that chlorophyll fluorescence was effective at monitoring the onset and development of stress and recovery of H. ovalis when exposed to crude oil, dispersant and a mixture of the two compounds. Photosynthetic pigment content generally confirmed the chlorophyll fluorescence response; however, several anomalies occurred. (author)

  4. Effects of Defoliations on the Chlorophyll Contents and Biomass of the Poplar (Populus simonii × P. nigra) and Larix gmelinii Seedlings%失叶率对小黑杨和兴安落叶松幼苗生物量和叶绿素含量的影响

    Institute of Scientific and Technical Information of China (English)

    李媛媛; 张凯; 李霜雯; 严善春

    2015-01-01

    叶绿素含量增加(P<0.05),第10天叶绿素含量降低(P <0.05),第15天与对照相比无差异,第20天叶绿素含量明显升高(P<0.05),到第25天叶绿素含量与对照相近;失叶量50%处理组,第5,15,20天叶绿素含量与对照相比明显降低(P<0.05),且第5天和20天亦显著低于另外2组处理;第10天与对照及另外2组差异不显著(P﹥0.05),到第25天叶绿素含量明显高于对照和其他2组处理(P <0.05)。【结论】失叶对杨树和兴安落叶松的固碳能力和光合生理反应均有影响,杨树和落叶松通过增加叶绿素含量,提高单位面积的光合能力,在一定程度上补偿其固碳能力的降低和生物量的损失,且杨树的补偿能力强于落叶松。%Defoliations by leaf/needle-feeding insects can cause significant losses of tree growth,biomass,and carbon storage. Potential effects of artificial defoliations at 0%,25%,50% and 75% levels to mimic the defoliator damages on biomass and chlorophyll contents of the poplar (Populus simonii × P. nigra) and larch (Larix gmelinii) seedlings at 5, 10,15,20 and 25 days after each treatment were investigated in the current study. Our results showed that there were no significant differences among the treatments in the plant height and root length (P > 0. 05) for both tree species,except that 50% larch seedling needle removal resulted in a significant increase of root length ( P “b”) . Significant increase of chlorophyll contents already occurred at 5th day after the defoliation,with the 75% level being significantly higher than the control and the two lower levels (25%and 50%) for both chlorophyll“a”and“a”+“b”(P0. 05). At 20th day after the defoliation,chlorophyll“a”,“b”and“a”+“b”contents of 50% defoliation were significantly lower than those of 25% defoliation and control; and slightly lower ( but not significantly) than those of the 75% level. At 25th day after the defoliation

  5. [Pigment composition and photosynthetic activity of pea chlorophyll mutants].

    Science.gov (United States)

    Ladygin, V G

    2003-01-01

    Pea chlorophyll mutants chlorotica 2004 and 2014 have been studied. The mutants differ from the initial form (pea cultivar Torsdag) in stem and leaf color (light green in the mutant 2004 and yellow-green in the mutant 2014), relative chlorophyll content (approximately 80 and 50%, respectively), and the composition of carotenoids: the mutant 2004 contains a significantly smaller amount of carotene but accumulates more lutein and violaxanthine; in the mutant 2014, the contents of all carotenoids are decreased proportionally to the decrease in chlorophyll content. It is shown that the rates of CO2 assimilation and oxygen production in the mutant chlorotica 2004 and 2014 plants are reduced. The quantum efficiency of photosynthesis in the mutants is 29-30% lower than in the control plants; in their hybrids, however, it is 1.5-2 higher. It is proposed that both the greater role of dark respiration in gas exchange and the reduced photosynthetic activity in chlorotica mutants are responsible for the decreased phytomass increment in these plants. On the basis of these results, the conclusion is drawn that the mutations chlorotica 2004 and 2014 affect the genes controlling the formation and functioning of various components of the photosynthetic apparatus. PMID:12942751

  6. Effects of di-n-butyl phthalate and di (2-ethylhexyl) phthalate on the growth, photosynthesis, and chlorophyll fluorescence of wheat seedlings.

    Science.gov (United States)

    Gao, Minling; Qi, Yun; Song, Wenhua; Xu, Haoran

    2016-05-01

    Phthalates are commonly used man-made chemicals that can be released into soil, water, and the atmosphere. The potential toxicity of phthalates on wheat seedlings has not been well studied. To better understand the deleterious effects of di-n-butyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP) on wheat seedlings, their influences on the following were investigated: plant growth, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), intercellular CO2 concentration (Ci), chlorophyll content, initial fluorescence (F0), maximal photochemical efficiency (Fv/Fm), photochemical quenching (qP), non-photochemical quenching (qN), effective quantum yield of photosystem II (ΦPSII), and photosynthetic electron transport rate (ETR). Compared with the control, the growth indices (plant height, fresh and dry weights of shoots, fresh and dry weights of roots), Pn, Gs, Tr, Ci, chlorophyll content, Fv/Fm, qP, ΦPSII, and ETR decreased in the 5 μg mL(-1) and 10 μg mL(-1) DBP and DEHP treatments, whereas F0 and qN increased. When wheat seedlings were treated with 20 μg mL(-1) of DBP and DEHP, the growth indices, Pn, Gs, Tr, chlorophyll content, Fv/Fm, qP, qN, ΦPSII, and ETR decreased significantly, whereas Ci and F0 increased. A decrease in the Pn of wheat seedlings was mainly caused by stomatal limitation in the 5 μg mL(-1) and 10 μg mL(-1) DBP and DEHP treatments. However, stomatal and non-stomatal limitations may have caused the reduction in Pn in the 20 μg mL(-1) DBP and DEHP treatments. Notably, the noxious effect of DBP on the wheat seedlings was significantly greater than that of DEHP. PMID:26928333

  7. Predicting crappie recruitment in Ohio reservoirs with spawning stock size, larval density, and chlorophyll concentrations

    Science.gov (United States)

    Bunnell, David B.; Hale, R. Scott; Vanni, Michael J.; Stein, Roy A.

    2006-01-01

    Stock-recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from 11 Ohio reservoirs and larvae from 9 reservoirs during 1998-2001. We sampled chlorophyll as an index of reservoir productivity and obtained daily estimates of water elevation to determine the impact of hydrology on recruitment. Akaike's information criterion (AIC) revealed that Ricker and Beverton-Holt stock-recruit models that included chlorophyll best explained the variation in larval density and age-2 recruits. Specifically, spawning stock catch per effort (CPE) and chlorophyll explained 63-64% of the variation in larval density. In turn, larval density and chlorophyll explained 43-49% of the variation in age-2 recruit CPE. Finally, spawning stock CPE and chlorophyll were the best predictors of recruit CPE (i.e., 74-86%). Although larval density and recruitment increased with chlorophyll, neither was related to seasonal water elevation. Also, the AIC generally did not distinguish between Ricker and Beverton-Holt models. From these relationships, we concluded that crappie recruitment can be limited by spawning stock CPE and larval production when spawning stock sizes are low (i.e., CPE , 5 crappies/net-night). At higher levels of spawning stock sizes, spawning stock CPE and recruitment were less clearly related. To predict recruitment in Ohio reservoirs, managers should assess spawning stock CPE with trap nets and estimate chlorophyll concentrations. To increase crappie recruitment in reservoirs where recruitment is consistently poor, managers should use regulations to increase spawning stock size, which, in turn, should increase larval production and recruits to the fishery.

  8. Effects of different cytokinins on chlorophyll retention in the moss Bryum argenteum (Bryaceae)

    OpenAIRE

    SABOVLJEVIĆ, ANETA; Sabovljević, Marko; VUKOJEVIĆ, VANJA

    2010-01-01

    Background and Purpose: Cytokinins are a group of plant hormones that have an important role in plant growth and developmental processes. Chlorophyll content is an extremely important parameter in estimating the plant production level. Since bryophytes do not have such economical importance as vascular plants and their production in many ecosystems is small, they remain uninteresting for studying their chlorophyll level. The aim of this study was to compare the effect of different cytok...

  9. Assessment of Salt Tolerance in Pepper Using Chlorophyll Fluorescence and Mineral Compositions

    OpenAIRE

    Mohammad Reza Zare Bavani; Gholamali Peyvast; Mahmoud Ghasemnezhad; Akbar Forghani

    2016-01-01

    In this study, leaf chlorophyll fluorescence and mineral compositions was used to compare pepper (Capsicum annuum L.) cultivars response to salt stress. Twentysix pepper cultivars were exposed to salt stress (100 mM NaCl) during two weeks. Thereafter, chlorophyll fluorescence components, stress tolerance index (STI), sodium, potassium and calcium content were measured. The results showed that a significant difference has been found among pepper cultivars for all studied characteristics....

  10. CHLOROPHYLL AND CAROTENOID PIGMENTS IN THE PEEL AND FLESH OF COMMERCIAL APPLE FRUITS VARIETIES.

    OpenAIRE

    Delgado-Pelayo, Raúl; Gallardo Guerrero, Lourdes; Hornero-Méndez, Dámaso

    2014-01-01

    Apple (Malus x domestica Borkh) has always been considered a fruit with low chlorophyll and carotenoid contents; however these pigments contribute also to the external (peel) and internal (flesh) fruit colouration, as well as to the health benefits associated with the regular consumption of this fruit. In the present work we studied the chlorophyll and carotenoid composition of the peel and flesh of thirteen marketed apple varieties presenting different external colouration (gr...

  11. 盐胁迫对玉米种子萌发、幼苗叶绿素含量和渗透势的影响%Effects of Salt Stress on Seed Germination and Seedling Chlorophyll Content and Osmotic Potential of Maize

    Institute of Scientific and Technical Information of China (English)

    付长方; 张海艳

    2015-01-01

    The effects of salt stress on seed germination , seedling growth and chlorophyll content and os-motic potential in maize leaves were studied with NaCl to simulate salt environment .The results indicated that the effects of 100 mmoL・ L-1 NaCl on seed germination and seedling growth of Zhengdan 958 was not signifi-cant , but the seed germination and seedling growth of Ludan 661 were significantly promoted .The seed germi-nation and seedling growth of Zhengdan 958 and Ludan 661 were inhibited significantly by the treatments of 200 mmoL・ L-1 NaCl and much higher concentrations .Under the 200 or 250 mmoL・ L-1 NaCl treatment , the root growth was inhibited more than shoot growth , and the chlorophyll content increased; but under the treatments with higher concentrations , the root growth was inhibited less than shoot growth , and the chlorophyll content decreased .With the increase of NaCl concentration , the osmotic potential decreased .Therefore, maize had some salt tolerance ability .The seed germination and seedling growth could be promoted under low-er NaCl concentration (≤100 mmoL・ L-1 NaCl ) and be inhibited under high NaCl concentrations (≥200 mmoL・ L-1 NaCl) .The effects of salt stress on seed germination and seedling growth of corn were different a-mong different maize varieties .%用NaCl模拟盐环境,分析不同浓度盐处理对玉米种子发芽、幼苗生长及其叶片叶绿素含量、渗透势的影响。结果表明,100 mmoL・ L-1 NaCl对郑单958的种子萌发和幼苗生长没有显著影响,对鲁单661的种子萌发和苗高、苗重有显著促进作用;200 mmoL・ L-1和更高浓度的NaCl对两个玉米品种的种子萌发和幼苗生长均有显著抑制作用。200 mmoL・ L-1或250 mmoL・ L-1 NaCl处理时,根的受抑制作用大于苗,叶片叶绿素含量增加;更高浓度NaCl处理时,根的受抑制作用小于苗,叶绿素含量降低。随着NaCl浓度的升高,叶片渗透势呈降

  12. Efficient Chlorophyll Fluorescence Measurements of Sugarcane

    Science.gov (United States)

    As with many crops, chlorophyll fluorescence emission is a promising tool for measuring responses of sugarcane (Saccharum spp.) to biotic and abiotic stresses. Chlorophyll fluorescence can be easily measured using portable fluorometers. However, several factors should be considered in order to op...

  13. Chlorophyll fluorescence imaging of cadmium-treated white cabbage plants

    Directory of Open Access Journals (Sweden)

    Borek M.

    2013-04-01

    Full Text Available The chlorophyll fluorescence imaging technique is a valuable tool to study the impact of heavy metal stress in plants. The aim of this paper was to investigate the influence of Cd on photosynthetic apparatus of white cabbage (Brassica oleracea subsp. capitata f. alba plants. Two cabbage cultivars ‘Ditmarska Najwcześniejsza’ (‘DN’; early and ‘Amager Polana’ (‘AP’; late were used. Cd was applied before planting seedlings (10 mg Cd kg−1 DM of soil.. Measurements were performed at the 3rd leaf after 2 weeks of planting. The level of Cd-induced stress to plants was estimated by chlorophyll (Chl content (photometrically and analyses of images and numeric values of the major fluorescence parameters of Chl (Chl fluorescence imaging system FluorCam. Cd negatively affected the chlorophyll content and Fv/Fm, Fv’/Fm’, Φ PSII and qP in leaves of early cultivar of white cabbage. However, in the case of late cv. we did not observe such distinct changes. It suggests that late cultivars. are more resistant to Cd than the early ones. Considering methodological aspect of the study, Chl fluorescence imaging can better reveal some alterations within the leaf, because numeric values of specific parameters, which are the averaged data collected from the whole leaf, cannot reflect the tissue specificity. Abbreviations: HM – heavy metal, Cd – cadmium, Chl – chlorophyll, Fv/Fm – photochemical efficiency of PSII in the dark-adapted state, F‘v’/F‘m’ – PSII maximum efficiency, Φ PSII – quantum efficiency of PSII electron transport, NPQ – nonphotochemical quenching of maximal Chl fluorescence, qP – photochemical quenching coefficient.

  14. TRACKING CHANGES IN CHLOROPHYLL AND CAROTENOIDS IN THE PRODUCTION PROCESS OF FROZEN SPINACH PURÉE

    Directory of Open Access Journals (Sweden)

    Andrea Mendelová

    2014-02-01

    Full Text Available Spinach is in the professional and general public considered highly nutritious vegetable with many beneficial effects on human health. It is a rich source of antioxidant active substances, especially chlorophyll, carotenoids, flavonoids and minerals especially zinc and copper. This work studies the changes of chlorophyll and carotenoids that occur after mass production technology of freezing at -37 °C. Before freezing was used blanching operation. In this work we used a variety Boeing, Boa, Beaver, Hudson and Chica. The highest content of all monitored parameters are found in fresh leaves of sampled Hudson. We found that within the processing decreases chlorophyll in 16.6%, 13.8% of chlorophyll b and carotenoids of 6.15%. This decrease was in all cases statistically significant.

  15. 基于叶绿素评价高效氯氟氰菊酯对三种农作物生态安全性%The Safety Assessment of Lambda-cyhalothrin for The Three Crops According to Chlorophyll Contents

    Institute of Scientific and Technical Information of China (English)

    李晴晴; 丁艳梅; 徐笑; 王涛; 张悦; 杜宝贞; 曲爱军

    2013-01-01

    对大田栽培作物玉米、棉花、红薯和花生,用喷雾器喷施不同浓度杀虫剂高效氯氟氰菊酯,24h后测定4种作物叶绿素和类胡萝卜素的含量.结果表明,3 000倍高效氯氟氰菊酯对红薯和玉米是安全的,而高效氯氟氰菊酯对棉花则完全是有利的.%In the field, the leaves of maize, cotton and sweet potato were spayed the different concentrations of lambda-cyhalothrin. The contents of chlorophyll and carotenoid were tested at the 24th hour. The result showed that lambda-cyhalothrin which concentration was 3 000 times for the sweet potato and maize was safe. It was not harmful of lambda-cyhalothrin between 1 000 to 3 000 times to the cotton.

  16. Effects of particle size and dry matter content of a total mixed ration on intraruminal equilibration and net portal flux of volatile fatty acids in lactating dairy cows

    DEFF Research Database (Denmark)

    Storm, Adam Christian; Kristensen, Niels Bastian

    2010-01-01

    pH or milk fat percentage. Cows maintained average ventral ruminal pH of 6.65 ± 0.02, medial ruminal pH of 5.95 ± 0.04, and milk fat of 4.42 ± 0.12% with chewing time of 28.0 ± 2.1 min/kg of DM when fed short particles. The medial ruminal pool of wet particulate matter was decreased by 10...... and permanent indwelling catheters in the major splanchnic blood vessels were used. The experimental design was a 4 × 4 Latin square with a 2 × 2 factorial design of treatments. Treatments differed in forage (grass hay) particle size (FPS; 3.0 and 30 mm) and feed dry matter (DM) content of the total...... with short particles. The estimated ruminal fluid flow and therefore intraruminal VFA transport between medial and ventral phase was not affected by the FPS. In conclusion, the ruminal mat pool of VFA was proportional to the size of the mat and the only detected effects of decreasing FPS were...

  17. Net neutrality and investment incentives

    OpenAIRE

    Choi, Jay Pil; Kim, Byung-Cheol

    2008-01-01

    This paper analyzes the effects of net neutrality regulation on investment incentives for Internet service providers (ISPs) and content providers (CPs), and their implications for social welfare. We show that the ISP's decision on the introduction of discrimination across content depends on a potential trade-off between network access fee and the revenue from the trade of the first-priority. Concerning the ISP's investment incentives, we find that capacity expansion affects the sale price of ...

  18. On the influence of dissolved organic-matter on remote-sensing of chlorophyll in the straits of skagerrak and kattegat

    OpenAIRE

    Karabashev, Gs

    1992-01-01

    An experimental techniques to estimate the influence of dissolved organic matter (DOM) on remote sensing of chlorophyll in water has been developed, based on the relationship between fluorescence and absorption of light by a substance. The profiles of fluorescence, chlorophyll content in sea water and estimates of light attenuation in water samples were used in the paper. These data have permitted to calculate the regressions linking fluorescence and light absorption at 450 nm by chlorophyll ...

  19. Influence of foliar application of silicon on chlorophyll fluorescence, photosynthetic pigments, and growth in water-stressed wheat cultivars differing in drought tolerance

    OpenAIRE

    MAGHSOUDI, KOBRA; Emam, Yahya; Ashraf, Muhammad

    2015-01-01

    The influence of foliar application of silicon (Si) on chlorophyll contents, chlorophyll fluorescence, and growth of four wheat cultivars differing in drought tolerance (Sirvan and Chamran, as relatively drought tolerant, and Shiraz and Marvdasht, as drought sensitive) was examined under water deficit (100% and 40% F.C.) created in a greenhouse. The results showed that water deficit decreased shoot and root lengths, shoot dry weight, root dry weight, water utilization efficiency, chlorophyll ...

  20. Thermal-based modeling of coupled carbon, water, and energy fluxes using nominal light use efficiencies constrained by leaf chlorophyll observations

    OpenAIRE

    Schull, M. A.; Anderson, M C; Houborg, R.; Gitelson, A.; Kustas, W.P.

    2015-01-01

    Recent studies have shown that estimates of leaf chlorophyll content (Chl), defined as the combined mass of chlorophyll a and chlorophyll b per unit leaf area, can be useful for constraining estimates of canopy light use efficiency (LUE). Canopy LUE describes the amount of carbon assimilated by a vegetative canopy for a given amount of absorbed photosynthetically active radiation (APAR) and is a key parameter for modeling land-surface carbon fluxes. A carbon-enabled version ...

  1. Thermal-based modeling of coupled carbon, water and energy fluxes using nominal light use efficiencies constrained by leaf chlorophyll observations

    OpenAIRE

    Schull, M. A.; Anderson, M C; Houborg, R.; Gitelson, A.; Kustas, W.P.

    2014-01-01

    Recent studies have shown that estimates of leaf chlorophyll content (Chl), defined as the combined mass of chlorophyll a and chlorophyll b per unit leaf area, can be useful for constraining estimates of canopy light-use-efficiency (LUE). Canopy LUE describes the amount of carbon assimilated by a vegetative canopy for a given amount of Absorbed Photosynthetically Active Radiation (APAR) and is a key parameter for modeling land-surface carb...

  2. Effects of lanthanum nitrate on growth and chlorophyll fluorescence characteristics of Alternanthera philoxeroides under perchlorate stress

    Institute of Scientific and Technical Information of China (English)

    谢寅峰; 蔡贤雷; 刘伟龙; 陶功胜; 陈倩; 张强

    2013-01-01

    To investigate the effects of exogenous lanthanum (La) on Alternanthera philoxeroides (Mart.) Griseb under perchlorate stress, changes in the growth and physiological parameters were investigated in solution culture experiments under controlled condi-tions. Different concentrations of La (NO3)3 were used in our study. It was shown that 0.1 and 0.5 mg/L La3+alleviated the inhibition effect of perchlorate on A. philoxeroides, including relative growth yield, dry weight of different organs, leaf area and root activity. And La3+prevented decline in the relative chlorophyll content and chlorophyll fluorescence parameters including Fv/Fm, Fv'/Fm',ΦPSI and ETR induced by perchlorate stress. Moreover, 0.5 mg/L La3+showed an optimal mitigative effect, while excess La3+(5.0 mg/L) led to synergistic effect on stress. Correlation analysis revealed a significant positive relationship between growth indexes and the chlorophyll fluorescence parameters, root activity and relative chlorophyll content (p<0.05). The results suggested that appropriate concentration of La3+could effectively alleviate growth inhibition and injury of A. philoxeroides caused by perchlorate stress, and the mitigative effect of La3+might be achieved by improving root activity, maintaining chlorophyll content and promoting photochemical efficiency of photosystem II of A. philoxeroides under perchlorate stress.

  3. Measuring Leaf Chlorophyll Concentration from Its Color: A Way in Monitoring Environment Change to Plantations

    CERN Document Server

    Shibghatallah, Muhammad Abdul Hakim; Suhandono, Sony; Viridi, Sparisoma; Kesuma, Teja

    2013-01-01

    Leaf colors of a plant can be used to identify stress level due to its adaptation to environmental change. For most leaves green-related colors are sourced from chlorophyll a and b. Chlorophyll concentration is normally measured using a spectrophotometer in laboratory. In some remote observation places, it is impossible to collect the leaves, preserve them, and bring them to laboratory to measure their chlorophyll content. Based on this need, measurement of chlorophyll content is observed through its color. Using CIE chromaticity diagram leaf color information in RGB is transformed into wavelength (in nm). Paddy seed with variety name IR-64 is used in observation during its vegetation stage t (age of 0-10 days). Light exposure time {\\tau} is chosen as environmental change, which normally should be about 12 hours/day, is varied (0-12 hours/day). Each day sample from different exposure time is taken, its color is recorded using HP Deskjet 1050 scanner with 1200 dpi, and its chlorophyll content is obtained from ...

  4. [Monitoring of the Moskva River Water Using Microbiological Parameters and Chlorophyll a Fluorescence].

    Science.gov (United States)

    Mosharova, I V; Il'inskii, V V; Matorin, D N; Mosharov, S A; Akulova, A Yu; Protopopov, F F

    2015-01-01

    The results of investigations of three Moskva River sites with different degree of pollution using a complex of microbiological characteristics and the parameters of chlorophyll a fluorescence are presented. We determined that the bacterioplankton seasonal dynamics at less polluted waters (Tushino and Vorobyovy Gory) were similar and differed significantly from one in more polluted waters (Dzerzhinskii). The number of bacteria with active electron transport chain, as well as their share in the bacterioplankton structure, was higher in the water of Dzerzhinskii (average annual values of 0.23 x 10(6) cells/mL and 14%), that in the less polluted water of Tushino and Vorobyovy Gory (0.14 x 10(6) cells/mL; 6% and 0.15 x 10(6) cells/mL; 7%, respectively). From April to October, the content of chlorophyll a and its photosynthetic activity were the highest in Tushino. In Dzerzhinskii, during spring the increase in photosynthetic activity commenced earlier and was more intensive that the increase in chlorophyll a content, i.e., the increase in phytoplankton biomass was temporarily suppressed. We suggest association of this phenomenon with suppression of organic matter synthesis by phytoplankton due to the high water pollution in Dzerzhinskii. The second autumn peak of chlorophyll a content, that was typical of clear water and was observed in Tushino, did not occur in Dzerzhinskii. We recommend combined application of these microbiological parameters and characteristics of chlorophyll a fluorescence for a monitoring. PMID:26964361

  5. Seasonal Composite Chlorophyll Concentrations - Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of chlorophyll concentrations in the Gulf of Maine. These raster images are seasonal composites, and were...

  6. Monolayers and multilayers of chlorophyll [correction of chlorophyl] a on a mercury electrode.

    Science.gov (United States)

    Moncelli, M R; Becucci, L; Dolfi, A; Tadini Buoninsegni, F; Agostiano, A

    2002-05-15

    A novel experimental technique used to investigate chlorophyll films on a hanging mercury drop electrode is described. Two different procedures are employed to prepare self-assembled chlorophyll monolayers and multilayers on the mercury electrode. Upon illuminating the chlorophyll a (Chl)-coated mercury electrode with an appropriate light source, the photocurrents generated by the Chl aggregates are measured under short-circuit conditions in the absence of photoartefacts. The preliminary results obtained by this novel technique are presented. PMID:12009465

  7. Transforming the Net Present Value for a Comparable One

    OpenAIRE

    Mária Illés

    2012-01-01

    This study examines the nature of net present value. It defines the economic content of the net present value and mathematically proves that definition is correct. This economic content inducts that the net present values are not comparable. The study systematically eliminates the distortion affects. The net present value transforms into a special kind of rate, namely, the modified difference between the factual and the required rate of return. The ranking list according to this transformed n...

  8. The Assessment of the Use of Eco-Friendly Nets to Ensure Sustainable Cabbage Seedling Production in Africa

    Directory of Open Access Journals (Sweden)

    Mathieu Ngouajio

    2012-12-01

    Full Text Available High seed cost accompanied by poor germination and seedling performance renders cabbage nursery and field production enterprises unsustainable to many small-scale growers in tropical and sub-tropical countries. In most nurseries, adverse ecological conditions and pest damage are among the major factors responsible for poor seedling performance. The objective of this study was to test the potential use of eco-friendly net (EFN covers as a low cost technology for sustainable cabbage seedling production. The study was a two-season experiment conducted using a randomized complete block design with five replications and two treatments. Treatments were: the standard open field transplant production (control and transplant production under 0.4 mm mesh polyethylene net covering. EFN covering increased both temperature and relative humidity, enhanced seedling growth and reduced insect pest damage. Seed germination and seedling emergence were under the net covering earlier. Higher seed germination and seedling survival were recorded under the EFN treatment, indicating a potential for reducing the seed requirement per unit area of cabbage production. Seedlings grown under the nets had higher stomatal conductance and leaf chlorophyll content; furthermore, they grew taller, with more leaves within a shorter period of time compared to the control seedlings. The use of EFN in cabbage nurseries offers a sustainable technology for enhancing seedling performance by reducing pest infestation, thereby lowering production cost and improving the grower’s income.

  9. Induction of chlorophyll chimeras and chlorophyll mutations in mungbean (Vigna radiata) cv. T44

    International Nuclear Information System (INIS)

    Uniform and healthy seeds of mungbean (Vigna radiata) cv. T44 were exposed to varying doses of gamma rays, ethyl methane sulphonate (EMS) and combination treatment of gamma rays with EMS. The data were recorded for seed germination, plant survival, frequency and spectrum of chlorophyll chimeras in M1 and chlorophyll mutations in M2 generation. Among all, the combination treatments were found most effective for inducing chlorophyll chimeras and chlorophyll mutations than the gamma rays or EMS alone. Of the mutants under reference, the albino, xantha and chlorina showed monogenic recessive while viridis exhibited digenic recessive inheritance. (author). 8 refs., 2 tabs

  10. ASP.NET website programming problem, design, solution, Visual Basic .NET edition

    CERN Document Server

    Bellinaso, Marco

    2003-01-01

    What is this book about? The C# edition of ASP.NET Website Programming Problem-Design-Solution has been phenomenally successful, gaining rave reviews for its unique approach and valuable content. The blend of theory and practice. Now, due to demand from readers, a Visual Basic .NET edition of the book has been produced. This edition will offer the same blend of theory and practice that won so many fans for the C# edition. The book has been completely re-edited to ensure that it address the needs of ASP.net developers who use VB.net. ASP.NET Website Programming shows you how to build an in

  11. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt

    The author describes a Petri net model, called coloured Petri nets (CP-nets), by means of which it is possible to describe large systems without having to cope with unnecessary details. The author introduces CP-nets and provide a first impression of their modeling power and the suitability of their...

  12. Photosynthesis and regulation of rubisco activity in net phytoplankton from Delaware Bay

    Energy Technology Data Exchange (ETDEWEB)

    MacIntyre, H.L.; Geider, R.J. [Univ. of Delaware, Lewes, DE (United States); McKay, R.M. [Brookhaven National Lab., Upton, NY (United States)

    1996-10-01

    Net phytoplankton (>20 {mu}m) comprised 51 {plus_minus} 9% of the total chlorophyll (Chl) in a Skeletonema costatum-dominated spring bloom in Delaware Bay. The net phytoplankton had low C:N and high protein:carbohydrate ratios, indicating that their growth was nutrient-replete. Their photosynthetic responses were characterized by low specific absorption, low light-limited and light-saturated rates of photosynthesis, and high quantum yields, indicative of acclimation to low irradiance and internal self-shading. High fucoxanthin: Chl ratios also indicated low light acclimation, but high photoprotective xanthophyll: Chl ratios suggested a high capacity for photoprotective energy dissipation. Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) could be activated and deactivated in response to changes in irradiance and was fully activated at the surface of the water column and fully deactivated in aphotic deep water. Maximum Rubisco activity was correlated with Rubisco content and bulk protein content of the phytoplankton and with light-saturated rates of photosynthesis measured in short (<20-min) incubations. Long (60-min) incubations caused a decrease in the light-saturated rate of photosynthesis, possibly because of feedback limitation. While feedback limitation is unlikely to occur in the water column it should be considered when estimating productivity in well-mixed waters from fixed light-depth incubations. 90 refs., 7 figs., 2 tabs.

  13. Net Neutrality, Business Models, and Internet Interconnection

    OpenAIRE

    Jay Pil Choi; Doh-Shin Jeon; Byung-Cheol Kim

    2015-01-01

    We analyze the effect of net neutrality regulation in a two-sided market framework when content is heterogeneous in its sensitivity to delivery quality. We characterize the equilibrium in a neutral network constrained to offer the same quality vis-à-vis a non neutral network where Internet service providers are allowed to engage in second degree price discrimination with a menu of quality-price pairs. We find that the merit of net neutrality regulation depends crucially on content providers' ...

  14. EFFECT OF Cu AND Mn TOXICITY ON CHLOROPHYLL FLUORESCENCE AND GAS EXCHANGE IN RICE AND SUNFLOWER UNDER DIFFERENT LIGHT INTENSITIES

    Directory of Open Access Journals (Sweden)

    Hajiboland R.

    2007-06-01

    Full Text Available Copper (Cu and manganese (Mn are essential micronutrients for plants, but toxic at high concentrations. Responses of rice (Oryza sativa L. and sunflower (Helianthus annuus L. to toxic concentrations of Mn and Cu (up to 100 μM were studied under three light intensities including low (LL, PPFD=100, intermediate (IL, PPFD=500 and high (HL, PPFD=800 light intensities in hydroponic medium. Rice plants showed higher susceptibility than sunflower to both heavy metals concerning dry matter of shoot and root. Growing under higher light intensity strengthened the effect of Cu toxicity while ameliorated that of Mn, the latter was attributed to the lower Mn accumulation of HL plants in both shoot and root. Chlorophyll content of leaves was influenced negatively only by Cu treatment and that at the highest concentration in the medium (100 μM. Similar with growth results, reduction of net assimilation rate (A was higher in HL than LL plants treated by excess Cu, but in contrast to growth response, reduction was more prominent in sunflower than rice. Excess Mn-induced reduction of A was similar between LL and HL plants and was greater in sunflower than rice. Reduction of A was partly attributable to stomatal limitation, but non-stomatal mechanisms were also involved in this reduction. Copper and Mn treatment did not change the optimal quantum efficiency of PSII in dark-adapted chloroplasts (Fv/Fm ratio, but Fv/F0 was influenced particularly by Cu treatment, the reduction was higher in rice than sunflower and in HL compared to LL plants. Regarding excess Cu and Mn-mediated alterations in chlorophyll concentration, Fv/F0 and Tm values, it was suggested that, Cu and Mn toxicity depress the leaf photosynthetic capacity primarily by causing a significant alteration of the composition and functional competence of the photosynthetic units rather a reduction in the number of photosynthetic units (PSUs per unit leaf area.

  15. Chlorophyll formation and the development of photosynthesis in illuminated etiolated pea leaves.

    Science.gov (United States)

    Dowdell, R J; Dodge, A D

    1971-03-01

    The protein synthesis inhibitors chloramphenicol and terramycin, and light of low intensity were used to retard the rate of chlorophyll formation in illuminated dark grown pea leaves. In the control leaves the onset of photosynthesis, as measured by carbon dioxide exchange of the whole leaves, and reduction of ferricyanide and metmyoglobin and photo-oxidation of ascorbate in isolated chloroplasts, was observed after 2-4 hours illumination. The photosynthetic activity of the treated leaves did not commence until 10-12 hours illumination had elapsed. In both the control and treated leaves the onset of photosynthesis occurred when the total chlorophyll content was 0.04 mg/g fresh weight. The precise point of photosynthetic inception was apparently more related to the attainment of a specific total chlorophyl content than to the ratio of chlorophyll a to chlorophyll b. A marked increase in the evolution of carbon dioxide in the light was observed in the treated leaves during the first 10 hours of greening. This observation could not be ascribed to photorespiration since the leaves did not possess an active photosystem. It is suggested that the enhanced respiration may have been due to the light-induced activation of synthetic pathways responsible for the formation of chloroplast constituents. PMID:24493304

  16. Using leaf chlorophyll to parameterize light-use-efficiency within a thermal-based carbon, water and energy exchange model

    OpenAIRE

    HOUBORG RASMUS; Anderson, Martha C.; Daughtry, C.S.T.; W. P. Kustas; Rodell, Matthew

    2011-01-01

    Chlorophylls absorb photosynthetically active radiation and thus function as vital pigments for photosynthesis, which makes leaf chlorophyll content (Cab) useful for monitoring vegetation productivity and an important indicator of the overall plant physiological condition. This study investigates the utility of integrating remotely sensed estimates of Cab into a thermal-based Two-Source Energy Balance (TSEB) model that estimates land-surface CO2 and energy fluxes using an analytic...

  17. ContainerProbe-Net

    International Nuclear Information System (INIS)

    ContainerProbe-Net is a global system concept for high throughput Risk Screening of inter-modal containers while they are in motion. It will have the following detection capabilities: 1. Mis-declared hazardous materials: - illegal waste exports or imports; - hazardous materials causing many annual maritime insurance claims; - accumulated pest poisons. 2. Contraband materials: - smuggled and counterfeit goods to avoid import duties and restrictions; - narcotic drugs; - weapons for criminals; - illegal immigrants. 3. Terrorism materials: - explosives and precursors - Weapons of Mass Destruction - fissile materials. The demand for this type of detection capability with high throughput has been declared by the EU, USA and other nations as a consequence of the rising policy of Civil Security. Efforts to advocate ContainerProbe-Net to both U.S.A. and EU security research administrators are progressing as the private investment base grows. ContainerProbe-Net directly addresses the 100% Risk Screening of containers requirement. Neutron interrogation of each container on a train or on an automated vehicle passing through the ContainerProbe portal will provide information about the bulk elemental composition of the contents. A burst of pulsed neutrons for a combination of prompt γ and secondary neutron emissions can provide a measured 'fingerprint' which will remain constant from the start to the end of the container's journey. A period of two seconds is available per container in order to capture data for each container on a moving train. Contents of containers are already, to some extent, registered in the export logistics databases. However these disparate systems have evolved with computer science and the needs of ports and customs authorities. Today such systems are far from complete. The global access to such registered container data and the fusion of this information with actual physical measurement data is the Network part of the concept. Risk screening implies

  18. Analysis of in vivo chlorophyll fluorescence spectra to monitor physiological state of tomato plants growing under zinc stress.

    Science.gov (United States)

    Cherif, Jaouhra; Derbel, Najoua; Nakkach, Mohamed; Bergmann, Hubertus von; Jemal, Fatma; Lakhdar, Zohra Ben

    2010-12-01

    The effects of zinc (Zn) on plant chlorophyll fluorescence were investigated in 10-day-old tomato (Solanum lycopersicum) seedlings subjected for 7 days to a series of zinc (10, 50, 100 and 150μM) applied via the nutrient solution. The chlorophyll fluorescence spectra of leaves were recorded in the spectral region 650-800nm using the spectroscopic technique of ultraviolet light emitting diode induced fluorescence spectroscopy (UV-LED IFS). These spectra have been used to analyze the effect of several doses of zinc on the photosynthetic activities of tomato plants. The fluorescence intensity ratios (FIR) at the two maxima (F(690)/F(735)) of control as well as treated tomato plants were calculated by evaluating curve-fitted parameters using a Gaussian spectral function. The variable chlorophyll fluorescence decrease ratio (R(Fd)) values were determined from the fluorescence induction kinetics curves recorded at 690nm and 735nm. In addition, Zn accumulation in plants, plant growth, photosynthetic pigments content and malondialdehyde level (MDA, an index of lipid peroxidation) were also estimated. The results indicated that the plants treated with 10μM of zinc exhibited better growth, however, higher concentrations of zinc were harmful for plants. Excess Zn induced a decrease in the R(Fd) values, which was associated with a strong decline of the total chlorophylls content and an increase of MDA level. The total chlorophylls content decline could also be followed via an increase of the chlorophyll fluorescence ratio F(690)/F(735). PMID:20829059

  19. Chlorophyll Fluorescence Spectra as an Indicator of X-Ray + EMS-Induced Phytotoxicity in Safflower

    OpenAIRE

    Pandey, Jitendra Kumar; Srivastava, Preeti; Yadav, Ram Singh; Gopal, Ram

    2012-01-01

    The present investigation deals with the study of in vivo laser-induced chlorophyll florescence spectra (LICF) of safflower leaves (Carthamus tinctorius L.) for X-rays + EMS-treated plants. Seeds were treated with different doses of X-ray + EMS (5, 8, 12, 25, and 30 Kr + 0.5% EMS) and were grown in the green house. The effects of the concerned treatment on chlorophyll (Chl) contents and Chl fluorescence were investigated after 7 days of germination. Results obtained revealed that the values o...

  20. The spontaneous chlorophyll mutation frequency in barley

    DEFF Research Database (Denmark)

    Jørgensen, Jørgen Helms; Jensen, Hans Peter

    1986-01-01

    A total of 1866 barley plants were progeny tested in the greenhouse. Twenty-five plants segregated for newly arisen, spontaneous chlorophyll mutant genes. Among the total of 470,129 seedlings screened there were 79 mutants (1.7 .+-. 0.6 .times. 10-4). The data are added to data from three similar...... materials and the resulting estimate of the chlorophyll mutant frequency is 1.6 .times. 10-4 in about 1.43 million seedlings. The estimate of the chlorophyll mutation rate per generation is close to 67.3 .times. 10-4 per diploid genome or in the order of 6 .times. 10-7 per locus and haploid genome....

  1. 关于JJF 1070-2005《定量包装商品净含量计量检验规则》中抽样原理的探讨%Discussion on sampling principle in JF 1070-2005 "Quantitative net content of packaged goods rules of Metrological Inspection"

    Institute of Scientific and Technical Information of China (English)

    邵振威; 尚贤平; 杨眉

    2012-01-01

    本文简要介绍JJF 1070-2005《定量包装商品净含量计量检验规则》中的抽样方法,并对抽样原理进行理论分析和探讨,方便定量包装商品净含量计量检测人员更好地掌握定量包装商品的抽样和净含量的检验。%abstract: this paper gives a brief introduction of sampling method in JJF 1070-2005 "Quantitative net content of packaged goods rules of Metrological Inspection", and sampling principle is analyzed and discussed. It is convenient quantitative net content of packaged goods mettle detect personnel to better grasp the commodity that pack sample and clean content inspection.

  2. Annotating Coloured Petri Nets

    DEFF Research Database (Denmark)

    Lindstrøm, Bo; Wells, Lisa Marie

    2002-01-01

    Coloured Petri nets (CP-nets) can be used for several fundamentally different purposes like functional analysis, performance analysis, and visualisation. To be able to use the corresponding tool extensions and libraries it is sometimes necessary to include extra auxiliary information in the CP......-net. An example of such auxiliary information is a counter which is associated with a token to be able to do performance analysis. Modifying colour sets and arc inscriptions in a CP-net to support a specific use may lead to creation of several slightly different CP-nets – only to support the different...... uses of the same basic CP-net. One solution to this problem is that the auxiliary information is not integrated into colour sets and arc inscriptions of a CP-net, but is kept separately. This makes it easy to disable this auxiliary information if a CP-net is to be used for another purpose. This paper...

  3. Net Ecosystem Carbon Flux

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Net Ecosystem Carbon Flux is defined as the year-over-year change in Total Ecosystem Carbon Stock, or the net rate of carbon exchange between an ecosystem and the...

  4. Scoping studies for NET

    International Nuclear Information System (INIS)

    Scoping studies for NET using the SUPERCOIL system code are described. Capital cost optimized devices satisfying constraints imposed on stresses/strains, fields, access, etc. are compared. The main objectives are to determine what impact the main design characteristics, performance objectives and underlying plasma physics assumptions have on the parameters and cost of NET. A complete picture for choosing the main parameters of NET is developed and illustrated by the main NET study points used during the conceptual design phase. (orig.)

  5. Color measurements as a reliable method for estimating chlorophyll degradation to phaeopigments.

    Science.gov (United States)

    Sanmartín, P; Villa, F; Silva, B; Cappitelli, F; Prieto, B

    2011-07-01

    The application of biocides is a traditional method of controlling biodecay of outdoor cultural heritage. Chlorophyll degradation to phaeopigments is used to test the biocidal efficacy of the antimicrobial agents. In the present study, the usefulness of color measurements in estimating chlorophyll degradation was investigated. An aeroterrestrial stone biofilm-forming cyanobacterium of the genus Nostoc was chosen as test organism, comparing its different behaviour in both planktonic and biofilm mode of growth against the isothiazoline biocide Biotin T®. Changes in A(435 nm)/A(415 nm) and A(665 nm)/A(665a nm) and in the chlorophyll a and adenosine triphosphate (ATP) cell content were compared with the variations in the CIELAB color parameters (L*, a*, b*, C*(ab) and h(ab)). Our findings showed that both the phaeophytination indexes are useful in describing degradation of chlorophyl a to phaeopigments. Moreover, the CIELAB color parameters represented an effective tool in describing chlorophyll degradation. L* CIELAB parameter appeared to be the most informative parameter in describing the biocidal activity of Biotin T® against Nostoc sp. in both planktonic and biofilm mode of growth. PMID:20714920

  6. Effects of Molybdenum on the Intermediates of Chlorophyll Biosynthesis in Winter Wheat Cultivars Under Low Temperature

    Institute of Scientific and Technical Information of China (English)

    YU Min; HU Cheng-xiao; WANG Yun-hua

    2006-01-01

    The objective was to probe the site where the biosynthesis of chlorophyll was blocked under Mo deficiency at low temperature, which led to the decrease of chlorophyll in winter wheat cultivars. The intermediates of chlorophyll biosynthesis were analyzed in winter wheat cultivars in soil culture, miniblock culture, and solution culture to study the effects of Mo on chlorophyll biosynthesis without Mo addition (CK, soil available Mo 0.112 mg kg-1) and Mo addition (+ Mo,0.13 mg kg-1 Mo was added). Laevulinic acid (LA), the competitive analog of δ-aminolaevulinic acid (ALA) was also introduced in the experiment. The ratio of Chl a/Chl b was constant between CK and + Mo treatment, whereas it increased at low temperature, which indicated that Mo deficiency did not inhibit the transformation of Chl a to Chl b at low temperature. Under Mo deficiency, the contents of protochlorophyll (Pchl), Mg-protoporphyrin Ⅸ (Mg-Proto Ⅸ),protoporphyrin Ⅸ (proto Ⅸ), and uroporphyrinogen Ⅲ (Uro Ⅲ) decreased [Uro Ⅲ decreased significantly (P < 0.01)],whereas ALA and glutamate increased significantly (P < 0.01) compared with that of Mo addition, which suggested that the transformation from ALA to Ufo Ⅲ might be inhibited. The content of ALA reversed after addition of LA, it was significantly higher (P<0.01) in Mo addition than in CK. The results indicated that the transformation from ALA to Uro Ⅲ was blocked under Mo deficiency, which resulted in the inhibition of the biosynthesis of chlorophyll and led to the decrease of chlorophyll in winter wheat cultivars.

  7. Interpreting chlorophyll fluorescence signals: the effects of leaf age

    Science.gov (United States)

    Albert, L.; Vergeli, P.; Martins, G.; Saleska, S. R.; Huxman, T. E.

    2015-12-01

    Remote sensing of sun-induced chlorophyll fluorescence (SIF) promises robust estimation of carbon uptake across landscapes, as studies of plant physiology have shown that fluorescence emission is directly linked to photosynthesis at the leaf level. Yet most leaf-level studies demonstrating the link between chlorophyll fluorescence and photosynthesis have studied leaves in their prime: leaves that recently finished expansion and have yet to senesce. By contrast, remote sensing of landscapes involves observing leaves of different ages. For example, broadleaf deciduous forests and annual plant communities in temperate regions have leaves that develop and then senesce over the course of a growing season. In this experiment, we explored how leaf age and moisture availability affect steady-state fluoresence (Fs) at the leaf level. We simultaneously measured net photosynthesis (Anet) and Fs for leaves of known ages on greenhouse-grown dwarf Helianthus Annuus (sunflowers) from two watering treatments. To monitor plant water status, we measured pre-dawn water potential, and, for a subset of leaves, osmotic potential. Fully expanded or near-fully expanded leaves (~8 to ~23 days old) had higher Anet at saturating light than young, expanding leaves (less than 8 days old) or old leaves nearing senescence (>23 days old). We found a positive relationship between Fs and Anet, suggesting that the link between fluorescence emission and photosynthesis is robust across leaves of different ages. However, leaf age had marked effects on the light response curve of photosynthesis and fluorescence metrics. These results suggest that leaf age distribution, and changes in leaf age distribution due to phenology, should be considered when interpreting SIF at the landscape level.

  8. Study on the Relationship between Chlorophyll-a and Environmental Impact Factors in Deep Reservoir in Karst Areas——Taking Aha Reservoir for Example

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the relationship between chlorophyll-a and environmental impact factors in deep reservoir in Karst Areas.[Method] Taking Aha Reservoir for example,the changes of chlorophyll-a content and its relationship with environmental impact factors were researched,and the water quality of Aha Reservoir was assessed by means of modified Carlson trophic state index.[Result] Chlorophyll-a content in Aha Reservoir was higher in March,April,May and September and lower from June to August,a...

  9. Localisation of chlorophyll within the chloroplast

    NARCIS (Netherlands)

    Thomas, J.B.; Post, L.C.; Vertregt, N.

    1954-01-01

    Silver nitrate reduction was shown to occur in illuminated suspensions of Hibiscus grana. The action spectrum of this reduction, the reaction, proved to coincide satisfactorily with the chlorophyll absorption spectrum. Electron micrographs reveal that this reaction occurs in single lamellae. From

  10. Thin Layer Chromatography (TLC) of Chlorophyll Pigments.

    Science.gov (United States)

    Foote, Jerry

    1984-01-01

    Background information, list of materials needed, procedures used, and discussion of typical results are provided for an experiment on the thin layer chromatography of chlorophyll pigments. The experiment works well in high school, since the chemicals used are the same as those used in paper chromatography of plant pigments. (JN)

  11. Phytoplankton productivity quantified from chlorophyll fluorescence

    DEFF Research Database (Denmark)

    Hancke, Kasper; Dalsgaard, Tage; Sejr, Mikael Kristian;

    Phytoplankton are the main food source for marine life, and accurate uantification of its productivity is essential for understanding how marine food webs function. As a novel non-invasive technology, chlorophyll fluorescence can be used to assess in situ primary production in phytoplankton...

  12. Professional Enterprise NET

    CERN Document Server

    Arking, Jon

    2010-01-01

    Comprehensive coverage to help experienced .NET developers create flexible, extensible enterprise application code If you're an experienced Microsoft .NET developer, you'll find in this book a road map to the latest enterprise development methodologies. It covers the tools you will use in addition to Visual Studio, including Spring.NET and nUnit, and applies to development with ASP.NET, C#, VB, Office (VBA), and database. You will find comprehensive coverage of the tools and practices that professional .NET developers need to master in order to build enterprise more flexible, testable, and ext

  13. MANUFACTURE OF PHOTOVOLTAIC SOLAR CELL USING PLANT CHLOROPHYLL

    Science.gov (United States)

    To date, we have successfully manufactured working chlorophyll sensitized solar cells using chlorophyll (and b mixture) from spinach leaves. We have evaluated the electronic characteristics (voltage, current, and power outputs using different loading resistors) of this solar c...

  14. Ion contents, relative electrolyte leakage, proline accumulation, photosynthetic abilities and growth characters of oil palm seedlings in response to salt stress

    International Nuclear Information System (INIS)

    Oil palm seedlings were photo-autotrophically grown in MS medium and subsequently exposed to 0 (control), 25, 50, 100 or 200 mM NaCl. Sodium ions, proline content and the percentage of relative electrolyte leakage in seedlings subjected to salt stress increased, depending on the degree of salt concentrations. Sodium ion accumulation in oil palm seedlings grown under 200 mM NaCl was enriched and positively related to membrane injury or relative electrolyte leakage subsequently correlated with total chlorophyll degradation. Chlorophyll a (Chla), chlorophyll b (Chlb), total chlorophyll (TC), total carotenoids (Cx+c), maximum quantum yield of PSII (Fv/Fm), photon yield of PSII (OEPSII) and quantum efficiency of PSII (qP) in the seedlings under salt stress dropped significantly in comparison to the control group, leading to a reduction in net-photosynthetic rate (Pn) and growth, especially in 200 mM NaCl. A positive correlation between physiological and growth parameters, including sodium ion, relative electrolyte leakage, photosynthetic pigments and water oxidation in photosystem II, Pn and plant dry weight was found. These data may further be applied to establish criteria for salt tolerance screening in oil palm breeding programs. (author)

  15. Chlorophyll in tomato seeds: marker for seed performance?

    OpenAIRE

    Suhartanto, M.R.

    2002-01-01

    Using Xe-PAM, laser induced fluorometry and high performance liquid chromatography we found that chlorophyll was present in young tomato (cv. Moneymaker) seeds and was degraded during maturation. Fluorescence microscopy and imaging showed that the majority of chlorophyll is located in the seed coat but low levels of chlorophyll were also detected in the embryo, mainly in the radicle tip. Seed chlorophyll fluorescence appeared to be a sensitive indicator of physiological maturity of tomato see...

  16. Contribution of Chlorophyll Fluorescence to the Apparent Reflectance of Vegetation

    Science.gov (United States)

    Campbell, P. K. Entcheva; Middleton, E. M.; Kim, M. S.

    2007-01-01

    Current strategies for monitoring the physiologic status of terrestrial vegetation rely on remote sensing reflectance (R) measurements, whi ch provide estimates of relative vegetation vigor based primarily on chlorophyll content. Vegetation chlorophyll fluorescence (CF) offers a non-destructive alternative and a more direct approach for diagnosis of vegetation stress before a significant reduction in chlorophyll content has occurred. Thus, monitoring of vegetation vigor based on CF may allow earlier stress detection and more accurate carbon sequestra tion estimates, than is possible using R data alone. However, the observed apparent vegetation reflectance (Ra) in reality includes contrib utions from both the reflected and fluoresced radiation. The aim of t his study is to determine the relative R and CF fractions contributing to Ra from the vegetation in the red to near-infrared region of the spectrum. The practical objectives of the study are to: 1) evaluate t he relationship between CF and R at the foliar level for corn, soybean, maple; and 2) for corn, determine if the relationship established f or healthy (optimal N) vegetation changes under N defiiency. To obtai n generally applicable results, experimental measurements were conducted on unrelated crop and tree species (maple, soybean and corn), unde r controlled conditions and a gradient of inorganic N fertilization l evels. Optical R spectra and actively induced CF emissions were obtained on the same foliar samples, in conjunction with measurements of p hotosynthetic function, pigment levels, and C and N content. The comm on spectral trends or similarities were examined. On average, 10-20% of apparent R at 685 nm was actually due to CF. The spectral trends in steady and maximum F varied significantly, with Fs (especially red) showing higher ability for species and treatment separation. The relative contribution of ChF to R varied significantly among species, with maple emitting much higher F amounts, as

  17. Contribution of chlorophyll fluorescence to the apparent vegetation reflectance

    International Nuclear Information System (INIS)

    Current strategies for monitoring the physiologic status of terrestrial vegetation rely on remote sensing reflectance data, which provide estimates of vigor based primarily on chlorophyll content. Chlorophyll fluorescence (ChlF) measurements offer a non-destructive alternative and a more direct approach for diagnosis of vegetation stress before a significant reduction in chlorophyll content has occurred. Thus, technology based on ChlF may allow more accurate carbon sequestration estimates and earlier stress detection than is possible when using reflectance data alone. However, the observed apparent vegetation reflectance (Ra) in reality includes contributions from both the reflected and fluoresced radiation. The aim of this study is to determine the relative contributions of reflectance and ChlF fractions to Ra in the red to near-infrared region (650-800 nm) of the spectrum. The practical objectives of the study are to: 1) evaluate the relationship between ChlF and reflectance at the foliar level for corn, soybean and maple; and 2) for corn, determine if the relationship established for healthy vegetation changes under nitrogen (N) deficiency. To obtain generally applicable results, experimental measurements were conducted on unrelated crop and tree species (corn, soybean and maple) under controlled conditions and a gradient of inorganic N fertilization levels. Optical reflectance spectra and actively induced ChlF emissions were collected on the same foliar samples, in conjunction with measurements of photosynthetic function, pigment levels, and carbon (C) and N content. The spectral trends were examined for similarities. On average, 10-20% of Ra at 685 nm was actually due to ChlF. The spectral trends in steady state and maximum fluorescence varied significantly, with steady state fluorescence (especially red, 685 nm) showing higher ability for species and treatment separation. The relative contribution of ChlF to Ra varied significantly among species, with maple

  18. Bleaching of chlorophylls by UV irradiation in vitro: the effects on chlorophyll organization in acetone and n-hexane

    OpenAIRE

    JELENA ZVEZDANOVIC; DEJAN MARKOVIC

    2008-01-01

    The stability of chlorophylls toward UV irradiation was studied by Vis spectrophotometry in extracts containing mixtures of photosynthetic pigments in acetone and n-hexane. The chlorophylls underwent destruction (bleaching) obeying first-order kinetics. The bleaching was governed by three major factors: the energy input of the UV photons, the concentration of the chlorophylls and the polarity of the solvent, implying different molecular organizations of the chlorophylls in the two solvents.

  19. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Musall, Eike;

    2010-01-01

    The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...... and how the Net ZEB status should be calculated differs in most countries. This paper presents an overview of Net ZEBs energy calculation methodologies proposed by organisations representing eight different countries: Austria, Canada, Denmark, Germany, Italy, Norway, Switzerland and the USA. The...... different parameters used in the calculations are discussed and the various renewable supply options considered in the methodologies are summarised graphically. Thus, the paper helps to understand different existing approaches to calculate energy balance in Net ZEBs, highlights the importance of variables...

  20. Priced Timed Petri Nets

    OpenAIRE

    Abdulla, Parosh Aziz; Mayr, Richard

    2013-01-01

    We consider priced timed Petri nets, i.e., unbounded Petri nets where each token carries a real-valued clock. Transition arcs are labeled with time intervals, which specify constraints on the ages of tokens. Furthermore, our cost model assigns token storage costs per time unit to places, and firing costs to transitions. This general model strictly subsumes both priced timed automata and unbounded priced Petri nets. We study the cost of computations that reach a given control-state. In general...

  1. Alterations in Chlorophyll a Fluorescence and Pigments Concentration in the Leaves of Cauliflower and Broccoli Transplants Subjected to Chilling

    Directory of Open Access Journals (Sweden)

    Renata WOJCIECHOWSKA

    2016-06-01

    Full Text Available Chlorophyll a fluorescence parameters and photosynthetic pigments content in leaves of broccoli (Brassica oleracea L. var. italica cv. ‘Monaco’ F1 and cauliflower (Brassica oleracea L. var. botrytis cv. ‘Bruce’ F1 transplants were analyzed to investigate the effects of chilling temperatures (6 and 10 °C and the exposure length (1 or 2 weeks on the photosynthetic apparatus condition in 3-year experiment. Data were compared to control plants exposed to 14 °C for 1 and 2 weeks. The lowest values of maximum quantum efficiency of photosystem II (Fv/Fm and the performance index (PI were observed in cauliflower chilled at 6 °C for 2 weeks. This was not accompanied by any substantial reduction in chlorophylls concentration, however, significant correlations between Fv/Fm or PI and chlorophylls content in cauliflower leaves were found. There was no negative effects of chilling on photosynthetic activity and chlorophyll content in broccoli leaves, the amount of carotenoids significantly increased in the broccoli chilled for 2 weeks in 6 °C. The chlorophyll a fluorescence indices and accelerated carotenoids synthesis showed that broccoli had less vulnerable photosynthetic apparatus to stress-induced temperatures and more efficient protection mechanisms in comparison to cauliflower transplants.

  2. Statistical characteristics of chlorophyll-a concentration in Hong Kong′s coastal waters

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper seven of the ten Water Control Zones (WCZs) in Hong Kong′s coastal waters with monthly or bi-weekly sampling data of 17 parameters collected at 37 monitoring stations from 1988 to 1999 were selected to analyze the spatial and temporal variations of chlorophyll-a and its influencing factors. Cluster analysis was employed to group the monitoring stations based on the structure of the data set. Multiple step regression was employed to determine the significant influencing factors of chlorophyll-a level. The results suggest that all the monitoring stations could be grouped into two clusters. Cluster I with frequent red tide incidents comprises two WCZs which aresemi-enclosed bays. Cluster II with less red tide occurrence comprises the other five WCZs in an estuarine environment in the west. For both clusters, the organic contents indicator, BOD5, was a common significant influencing factor of the chlorophyll-a level. Nitrogen and light penetration condition related to turbidity, total volatile solids and suspended solids had more influence on the cholophyll-a level in Cluster I than in Cluster II, while phosphorus and oceanographic conditions associated with salinity, temperature, dissolved oxygen and pH were more important in Cluster II than in Cluster 1. Generally, there was a higher average chlorophyll-a level in winter and autumn in a year.The chlorophyll-a level was much higher in Cluster I than in Cluster II among all seasons. Although the chlorophyll-a concentration had great variations from place to place in Hong Kong′s coastal waters, it seemed to have a common long term fluctuation period of 8-10 years with a high-low-high variation in the period in the whole region, which might be influenced by other factors of global scale.

  3. Chlorophyll fluorescence remote sensing from space in scattering atmospheres: implications for its retrieval and interferences with atmospheric CO2 retrievals

    OpenAIRE

    J. McDuffie; L. Guanter; C. O'Dell; C. Frankenberg

    2012-01-01

    With the advent of dedicated greenhouse-gas space-borne spectrometers sporting high resolution spectra in the O2 A-band spectral region (755–774 nm), the retrieval of chlorophyll fluorescence has become feasible on a global scale. If unaccounted for, however, fluorescence can indirectly perturb the greenhouse gas retrievals as it perturbs the oxygen absorption features. As atmospheric CO2 measurements are used to invert net fluxes at the land-atmosphere interface, a bias caused by fluore...

  4. Effects of nitrogen form on growth, CO2 assimilation, chlorophyll fluorescence, and photosynthetic electron allocation in cucumber and rice plants*

    OpenAIRE

    Zhou, Yan-Hong; Zhang, Yi-li; Wang, Xue-Min; Cui, Jin-xia; Xia, Xiao-Jian; Kai SHI; Yu, Jing-quan

    2011-01-01

    Cucumber and rice plants with varying ammonium (NH4 +) sensitivities were used to examine the effects of different nitrogen (N) sources on gas exchange, chlorophyll (Chl) fluorescence quenching, and photosynthetic electron allocation. Compared to nitrate (NO3 −)-grown plants, cucumber plants grown under NH4 +-nutrition showed decreased plant growth, net photosynthetic rate, stomatal conductance, intercellular carbon dioxide (CO2) level, transpiration rate, maximum phot...

  5. Gas Exchange, Chlorophyll Fluorescence and Antioxidants as Bioindicators of Airborne Heavy Metal Pollution in Jeddah, Saudi Arabia

    OpenAIRE

    Hassan, I. A.; J.M. Basahi; I.M. Ismail

    2013-01-01

    Lettuce (Lactuca sativa L. cv. Romaine) plants were exposed to different levels of urbanization in Jeddah city, Saudi Arabia. They showed different degrees of visible injury symptoms and dramatic changes in enzymatic activities as well as net photosynthetic rates (PN), variable to maximum chlorophyll fluorescence (Fv/Fm) and stomatal conductance (gs).Visual symptoms of phytotoxicity of heavy metals were observed on plants grown at industrial and urban areas, where the concentrations of metals...

  6. Programming NET Web Services

    CERN Document Server

    Ferrara, Alex

    2007-01-01

    Web services are poised to become a key technology for a wide range of Internet-enabled applications, spanning everything from straight B2B systems to mobile devices and proprietary in-house software. While there are several tools and platforms that can be used for building web services, developers are finding a powerful tool in Microsoft's .NET Framework and Visual Studio .NET. Designed from scratch to support the development of web services, the .NET Framework simplifies the process--programmers find that tasks that took an hour using the SOAP Toolkit take just minutes. Programming .NET

  7. Game Coloured Petri Nets

    DEFF Research Database (Denmark)

    Westergaard, Michael

    2006-01-01

    This paper introduces the notion of game coloured Petri nets. This allows the modeler to explicitly model what parts of the model comprise the modeled system and what parts are the environment of the modeled system. We give the formal definition of game coloured Petri nets, a means of reachability...... analysis of this net class, and an application of game coloured Petri nets to automatically generate easy-to-understand visualizations of the model by exploiting the knowledge that some parts of the model are not interesting from a visualization perspective (i.e. they are part of the environment, and not...

  8. Fractal structures in casting films from chlorophyll

    Science.gov (United States)

    Pedro, G. C.; Gorza, F. D. S.; de Souza, N. C.; Silva, J. R.

    2014-04-01

    Chlorophyll (Chl) molecules are important because they can act as natural light-harvesting devices during the photosynthesis. In addition, they have potential for application as component of solar cell. In this work, we have prepared casting films from chlorophyll (Chl) and demonstrated the occurrence of fractal structures when the films were submitted to different concentrations. By using optical microscopy and the box-count method, we have found that the fractal dimension is Df = 1.55. This value is close to predicted by the diffusion-limited aggregation (DLA) model. This suggests that the major mechanism - which determines the growth of the fractal structures from Chl molecules - is the molecular diffusion. Since the efficiencies of solar cells depend on the morphology of their interfaces, these finds can be useful to improve this kind of device.

  9. [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. PMID:27228602

  10. Genetic analysis of sunflower chlorophyll mutants

    International Nuclear Information System (INIS)

    The method of getting the chlorophyll mutations in sunflower was developed by Y.D. Beletskii in 1969 with the use of N-nitroso-N-methylurea (NMH). Certain concentrations of NMH are known to induce plastid mutations in growing seeds, and their yield depends on the duration of the exposure. The given work presented studies on the influence of rifampicin (R) and 2,4-dinitrophenol (DNP) on the genetic activity NMH, as an inductor of plastid and nuclear mutations

  11. Extraction of Chlorophyll from Alfalfa Plant

    OpenAIRE

    Ali Khalid Khudair Al-Jomaily; Ahmed Jawad; Isam Kamal

    2006-01-01

    The extraction process of chlorophyll from dehydrated and pulverized alfalfa plant were studied by percolation method. Two solvent systems were used for the extraction namely; Ethanol-water and Hexane-Toluene systems . The effect of circulation rate, solvent concentration, and solvent volume to solid weight ratio were studied. In both ethanol water, and Hexane-Toluene systems it appears that solvent concentration is the most effective variable.

  12. Extraction of Chlorophyll from Alfalfa Plant

    Directory of Open Access Journals (Sweden)

    Ali Khalid Khudair Al-Jomaily

    2006-01-01

    Full Text Available The extraction process of chlorophyll from dehydrated and pulverized alfalfa plant were studied by percolation method. Two solvent systems were used for the extraction namely; Ethanol-water and Hexane-Toluene systems . The effect of circulation rate, solvent concentration, and solvent volume to solid weight ratio were studied. In both ethanol water, and Hexane-Toluene systems it appears that solvent concentration is the most effective variable.

  13. Chlorophyll fluorescence emission spectrum inside a leaf

    OpenAIRE

    Pedrós Esteban, Roberto; Moya, Ismael; Goulas, Yves; Jacquemoud, Stéphane

    2008-01-01

    Chlorophyll a fluorescence can be used as an early stress indicator. Fluorescence is also connected to photosynthesis so it can be proposed for global monitoring of vegetation status from a satellite platform. Nevertheless, the correct interpretation of fluorescence requires accurate physical models. The spectral shape of the leaf fluorescence free of any re-absorption effect plays a key role in the models and is difficult to measure. We present a vegetation fluorescence emission spectrum fre...

  14. Degradation of Chlorophyll Luminescence in Plants

    International Nuclear Information System (INIS)

    The chlorophyll photoluminescence intensity degradation of Vallisneria spiralis L. water plant is studied. It is shown that the degradation curve is rather well described by a sum of two hyperbolic functions. The rate of intensity degradation reduces at low temperatures. At room temperature, a slow restoration of the luminescent system is observed after the irradiation has been ceased. No restoration is detected at the liquid nitrogen temperature. A simplified model which describes the luminescence degradation according to the quadratic law is suggested.

  15. Chloroplastid pigment contents and chlorophyll a fluorescence in Amazonian tropical three species Concentração de pigmentos cloroplastídicos e fluorescência da clorofila a em espécies arbóreas tropicais da Amazônia

    Directory of Open Access Journals (Sweden)

    Ronaldo Ribeiro de Morais

    2007-10-01

    Full Text Available Plants react to changes in light and hydrological conditions in terms of quantity and composition of chloroplastidic pigments, which affects the photosynthetic properties and consequently the accumulation of plant biomass. Thus, the chloroplastidic pigment concentration and chlorophyll a fluorescence of three Amazonian species (Bertholletia excelsa, Carapa guianensis e Dipteryx odorata were investigated in sun and shade leaves form the tree crown collected during two distinct periods of precipitation (dry and rainy seasons. Pigment contents were determined by spectrophotometry and fluorescence variables were determined using a portable fluorometer. The results demonstrated that the species showed high concentrations of Chl a, Chl b e Chl total during the wet season in relation to the dry season, especially in shade leaves. A higher concentration of carotenoids was found in B. excelsa, when compared with leaves of C. guianensis and D. odorata. In leaves of B. excelsa and D. odorata no significant difference was found in relation to the photochemistry of photosystem II (Fv/Fm between the wet and dry seasons. In conclusion, the three species react differently to variations in the light and precipitation conditions regarding light capture, aspects that might be considered in the management of forest plantations.As plantas respondem a mudanças nas condições de luz e na disponibilidade hídrica em termos da quantidade e composição dos pigmentos cloroplastídicos, o que afeta as propriedades fotossintéticas e, conseqüentemente, o acúmulo de biomassa das espécies. Assim, a concentração de pigmentos cloroplastídicos e a fluorescência da clorofila a de três espécies arbóreas (Bertholletia excelsa, Carapa guianensis e Dipteryx odorata da Amazônia foi investigada em folhas sombreadas e não-sombreadas da copa das árvores e em dois períodos distintos de precipitação (chuvoso e seco. As concentrações de pigmentos foram determinadas por

  16. Crescimento e teores de clorofila em mudas de bananeira em função da supressão do pseudocaule, de doses de nitrogênio e de boro Growth and chlorophyll content of banana suckers in function of pseudostem suppression and doses of nitrogen and boron

    Directory of Open Access Journals (Sweden)

    Walter Esfrain Pereira

    2010-12-01

    plant. The data were submitted the variance analysis and of regression. The suppression in the pseudostem of the mother plant with elimination of the apical meristem of the rhizome increased the sucker number, with larger growth, except of the diameter of the rhizome which it reduced. In the plants with suppression, it reduced the sucker number which presented smaller growth. On the other hand, it increased the content of total chlorophyll. For the production of ‘Pacovan’ banana suckers, is recommended the suppression in the pseudostem of the mother plant with elimination of the meristem apical of the rhizome and the application of the N.

  17. Evaluating the relationship between leaf chlorophyll concentration and SPAD-502 chlorophyll meter readings.

    Science.gov (United States)

    Uddling, J; Gelang-Alfredsson, J; Piikki, K; Pleijel, H

    2007-01-01

    Relationships between chlorophyll concentration ([chl]) and SPAD values were determined for birch, wheat, and potato. For all three species, the relationships were non-linear with an increasing slope with increasing SPAD. The relationships for birch and wheat were strong (r (2) approximately 0.9), while the potato relationship was comparatively weak (r (2) approximately 0.5). Birch and wheat had very similar relationships when the chlorophyll concentration was expressed per unit leaf area, but diverged when it was expressed per unit fresh weight. Furthermore, wheat showed similar SPAD-[chl] relationships for two different cultivars and during two different growing seasons. The curvilinear shape of the SPAD-[chl] relationships agreed well with the simulated effects of non-uniform chlorophyll distribution across the leaf surface and multiple scattering, causing deviations from linearity in the high and low SPAD range, respectively. The effect of non-uniformly distributed chlorophyll is likely to be more important in explaining the non-linearity in the empirical relationships, since the effect of scattering was predicted to be comparatively weak. The simulations were based on the algorithm for the calculation of SPAD-502 output values. We suggest that SPAD calibration curves should generally be parameterised as non-linear equations, and we hope that the relationships between [chl] and SPAD and the simulations of the present study can facilitate the interpretation of chlorophyll meter calibrations in relation to optical properties of leaves in future studies. PMID:17342446

  18. Net4Care:

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Hansen, K.M.

    2012-01-01

    propose a software ecosystem approach for telemedicine applications, providing a framework, Net4Care, encapsulating national/global design decisions with respect to standardization while allowing for local innovation. This paper presents an analysis of existing systems, of requirements for a software...... ecosystem for telemedicine, and a summary of initial design decisions for the Net4Care framework....

  19. Growth response and toxic effects of three antibiotics on Selenastrum capricornutum evaluated by photosynthetic rate and chlorophyll biosynthesis

    Institute of Scientific and Technical Information of China (English)

    Binyang Liu; Weiqiu Liu; Xiangping Nie; Chao Guan; Yufeng Yang; Zhaohui Wang; Wei Liao

    2011-01-01

    The effects of three types of antibiotics (erythromycin,ciprofloxacin and sulfamethoxazole) on the photosynthesis of freshwater algae,Selenastrum capricornutum Printz,were investigated by determining the growth rate,chloroplast pigments content,seven main precursors (including δ-aminolevulinic acid,porphobilinogen,uroporphyrinogen Ⅲ,coproporphyrinogen Ⅲ,protoporphyrin Ⅸ,Mg-proporphyrin Ⅸ and protochlorophyllide),and photosynthetic rate during chlorophyll biosynthesis.The antibiotics significantly decreased the growth rate,chlorophyll content,and photosynthetic rate.Erythromycin induced a decreasing effect at a concentration of 0.06 mg/L,while ciprofloxacin and sulfamethoxazole achieved the same results at concentrations higher than 1.5 mg/L.Only erythromycin significantly inhibited chlorophyll biosynthesis,which indicated that it was considerably more toxic to S.capricornutum than ciprofloxacin and sulfamethoxazole,and may pose a high potential risk to aquatic ecosystems.

  20. [Ecological Effects of Algae Blooms Cluster: The Impact on Chlorophyll and Photosynthesis of the Water Hyacinth].

    Science.gov (United States)

    Liu, Guo-feng; He, Jun; Yang, Yi-zhong; Han, Shi-qun

    2015-08-01

    The response of chlorophyll and photosynthesis of water hyacinth leaves in different concentrations of clustered algae cells was studied in the simulation experiment, and the aim was to reveal the mechanism of the death of aquatic plants during algae blooms occurred through studying the physiological changes of the macrophytes, so as to play the full function of the ecological restoration of the plants. And results showed the dissolved oxygen quickly consumed in root zone of aquatic plants after algae blooms gathered and showed the lack of oxygen (DO water after the algae cell died and concentration of DTN in treatment 1 and 2 were 44.49 mg x L(-1) and 111.32 mg x L(-1), and the content of DTP were 2.57 mg x L(-1) and 9.10 mg x L(-1), respectively. The NH4+ -N concentrations were as high as 32.99 mg x L(-1) and 51.22 mg x L(-1), and the root zone with the anoxia, strong reducing, higher nutrients environment had a serious stress effects to the aquatic plants. The macrophytes photosynthesis reduced quickly and the plant body damaged with the intimidation of higher NH4+ -N concentration (average content was 45.6 mg x L(-1)) and hypoxia after algae cell decomposed. The average net photosynthesis rate, leaf transpiration rate of the treatment 2 reduced to 3.95 micromol (M2 x S)(-1), 0.088 micromol x (m2 x s)(-1), and only were 0.18 times, 0.11 times of the control group, respectively, at the end of the experiment, the control group were 22 micromol x (m2 x s)(-1), 0.78 micromol x (M2 x s)(-1). Results indicated the algae bloom together had the irreversible damage to the aquatic plants. Also it was found large amounts of new roots and the old roots were dead in the treatment 1, but roots were all died in the treatment 2, and leaves were yellow and withered. Experiment results manifested that the serious environment caused by the algae blooms together was the main reason of the death of aquatic plants during the summer. So in the practice of ecological restoration, it

  1. SPAD GREENNESS TO ESTIMATE GENOTYPIC VARIATION IN FLAG LEAF CHLOROPHYLL IN SPRING WHEAT UNDER MEDITERRANEAN CONDITIONS

    OpenAIRE

    Celaleddin BARUTCULAR; TOPTAS, Irem; TURKTEN, Hatice; Yildirim, Mehmet; KOC, Mujde

    2015-01-01

    Leaf chlorophyll (Chl) is emphasized as an indicator for photosynthesis in wheat (Triticum aestivum L.). SPAD greenness meters are used to predict extractable Chl, but few studies have evaluated relationships between flag leaf greenness and Chl among wheat genotypes. Sixteen spring wheat genotypes with similar development patterns were studied in eight environments (2 years, 2 irrigation treatments and 2 sowing times) to investigate the precision of the SPAD-502 meter to predict Chl content/c...

  2. Monitoring of Plant Chlorophyll and Nitrogen Status Using the Airborne Imaging Spectrometer AVIS

    OpenAIRE

    Oppelt, Natascha

    2002-01-01

    Airborne hyperspectral remote sensing enables not only spatial monitoring of vegetation cover, but also the derivation of individual plant constituents such as chlorophyll and nitrogen content. These are important parameters for optimised agricultural management on a field basis through the possibility of spatially differentiated fertilisation and for hydrological and vegetation yield modelling. The use of existing airborne imaging spectrometers is cost-intensive. Moreover, it ...

  3. Temperature and plant adaptation. I. Interaction of temperature and light in the synthesis of chlorophyll in corn.

    Science.gov (United States)

    McWilliam, J R; Naylor, A W

    1967-12-01

    The effect of temperature and light intensity have been studied in relation to the greening of etiolated corn (Zea mays cv. Pioneer 309-B) seedlings. Chlorophyll accumulation is rapid at high temperature (28 degrees ) under all conditions of light intensity. At low temperature (16 degrees ), and particularly in combination with high light intensity (3000-4500 ft-c), the accumulation of both chlorophyll and carotene is inhibited.Low pigment content at 16 degrees is not directly due to a block in the pigment synthesizing mechanism, but rather to the photodestruction of chlorophyll prior to its stabilization in the membrane structure of the chloroplast lamellae. The parallel reduction in carotene content at high light intensity is probably a contributing factor, because of its role in protecting chlorophyll from photodestruction. The greater severity of photo-oxidation of chlorophyll at low temperature in corn when compared with wheat, appears to be due to a slower rate of protochlorophyllide synthesis and subsequent esterification. Thus in corn at 16 degrees there is a prolongation of the photosensitive stage during chlorophyll synthesis. Photo-oxidation at 16 degrees has also been shown to be a function of the incident light energy, with the photosynthetic pigments acting as receptors for their own destruction.In comparison with the behavior of corn, wheat seedlings green rapidly at high light intensity at both 16 degrees and 28 degrees . This contrasting temperature response with respect to chlorophyll synthesis may underlie a fundamental difference in adaptation of these 2 species to growth in the temperate zones of the world. PMID:16656709

  4. Fine mapping of a dominant gene conferring chlorophyll-deficiency in Brassica napus.

    Science.gov (United States)

    Wang, Yankun; He, Yongjun; Yang, Mao; He, Jianbo; Xu, Pan; Shao, Mingquan; Chu, Pu; Guan, Rongzhan

    2016-01-01

    Leaf colour regulation is important in photosynthesis and dry material production. Most of the reported chlorophyll-deficient loci are recessive. The dominant locus is rarely reported, although it may be more important than the recessive locus in the regulation of photosynthesis efficiency. During the present study, we mapped a chlorophyll-deficient dominant locus (CDE1) from the ethyl methanesulfonate-mutagenized Brassica napus line NJ7982. Using an F2 population derived from the chlorophyll-deficient mutant (cde1) and the canola variety 'zhongshuang11', a high-density linkage map was constructed, consisting of 19 linkage groups with 2,878 bins containing 13,347 SNP markers, with a total linkage map length of 1,968.6 cM. Next, the CDE1 locus was mapped in a 0.9-cM interval of chromosome C08 of B. napus, co-segregating with nine SNP markers. In the following fine-mapping of the gene using the inherited F2:3 populations of 620 individuals, the locus was identified in an interval with a length of 311 kb. A bioinformatics analysis revealed that the mapping interval contained 22 genes. These results produced a good foundation for continued research on the dominant locus involved in chlorophyll content regulation. PMID:27506952

  5. Teores de clorofila determinados por medidor portátil e sua relação com formas de nitrogênio em folhas de tomateiro cultivados em dois tipos de solo Relations among chlorophyll contents determined by a portable meter and nitrogen forms in leaves of tomatoes cultivated in two soil types

    Directory of Open Access Journals (Sweden)

    TADEU GRACIOLLI GUIMARÃES

    1999-01-01

    das leituras obtidas no medidor SPAD, permitiu o ajuste de equação linear (CP = -77,233 + 3,54725** SPAD R2 = 0,766.This work aimed to determine chlorophyll concentrations of tomato (Lycopersicon esculentum Mill. plants cv. Santa Clara fertilized with five nitrogen (N rates by means of conventional laboratory methodology and by the SPAD-502 portable chlorophyll meter. The relationship between chlorophyll and N values was determined by these two methods. Tomato plants were grown in pots with a clay soil classified as Cambic Red-Yellow Podsol (CRP and a sand-course soil classified as Quartzic Sand (QS, and received five N rates (25, 125, 225, 325 and 425 mg. dm-3 sidedressed as nutrient solutions. At the onset of 3rd cluster anthesis, chlorophyll concentrations were determined in leaves opposite to this cluster by the portable chlorophyll meter SPAD-502 and at laboratory by Arnon's methodology. NO3-N was determined in petiole sap and in dry matter, while NO3-N, org-N and total-N were determined in leaf blade dry matter. Chlorophyll concentrations increased with N rates irrespective of method of determination, in both soils. Critical levels in soils CRP and QS were, respectively, 77.3 and 83.6 mg. cm-2 by laboratory methodology and 45.5 and 43.8 SPAD units by the portable meter. Correlation coefficients of chlorophyll concentrations with top dry weight and N forms were greater for the SPAD method. Both methods of chlorophyll determination presented greatest correlation with sap NO3-N in soil CRP, and with org-N and total-N in soil QS. The estimative of chlorophyll concentrations (laboratory method by means of SPAD readings allowed the adjustment of a linear equation (CP = -77.233 + 3.54725** SPAD R2 = 0.766.

  6. Pro NET Best Practices

    CERN Document Server

    Ritchie, Stephen D

    2011-01-01

    Pro .NET Best Practices is a practical reference to the best practices that you can apply to your .NET projects today. You will learn standards, techniques, and conventions that are sharply focused, realistic and helpful for achieving results, steering clear of unproven, idealistic, and impractical recommendations. Pro .NET Best Practices covers a broad range of practices and principles that development experts agree are the right ways to develop software, which includes continuous integration, automated testing, automated deployment, and code analysis. Whether the solution is from a free and

  7. Instant Lucene.NET

    CERN Document Server

    Heydt, Michael

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. A step-by-step guide that helps you to index, search, and retrieve unstructured data with the help of Lucene.NET.Instant Lucene.NET How-to is essential for developers new to Lucene and Lucene.NET who are looking to get an immediate foundational understanding of how to use the library in their application. It's assumed you have programming experience in C# already, but not that you have experience with search techniques such as information retrieval theory (although there will be a l

  8. Salt stress change chlorophyll fluorescence in mango

    Directory of Open Access Journals (Sweden)

    Cicero Cartaxo de Lucena

    2012-12-01

    Full Text Available This study evaluated the tolerance of mango cultivars 'Haden', 'Palmer', 'Tommy Atkins' and 'Uba' grafted on rootstock 'Imbú' to salt stress using chlorophyll fluorescence. Plants were grown in modified Hoagland solution containing 0, 15, 30, and 45 mmol L-1 NaCl. At 97 days the parameters of the chlorophyll fluorescence (F0, Fm, Fv, F0/Fm, Fv/Fm, Fv'/Fm', ΦPSII = [(Fm'-Fs/(Fm'], D = (1- Fv'/Fm' and ETR = (ΦPSII×PPF×0,84×0,5 were determined. At 100 days, the leaf emission and leaf area, toxicity and leaf abscission indexes were determined. In all cultivars evaluated, in different degree, there were decreases in photochemical efficiency of photosystem II, enhanced concentrations from 15 mmol L-1 NaCl. The decreases in the potential quantum yield of photosystem II (Fv/Fm were 27.9, 18.7, 20.5, and 27.4%, for cultivars 'Haden', 'Palmer', 'Tommy Atkins', and 'Uba', respectively, when grown in 45 mmol L-1 NaCl. It was found decreases in leaf emission and mean leaf area in all cultivars from 15 mmol L-1 NaCl. There were increases in leaf toxicity of 33.0, 67.5, 41.6 and 80.8% and in leaf abscission of 71.8, 29.2, 32.5, and 67.9% for the cultivars 'Haden', 'Palmer', 'Tommy Atkins', and 'Uba' respectively, when grown in 45 mmol L-1 NaCl. Leaf toxicity and leaf abscission were not observed in 15 mmol L-1 NaCl. The decrease in Fv/Fm ratio were accompanied by decreasing in leaf emission and increased leaf toxicity index, showing, therefore, the potential of chlorophyll fluorescence in the early detection of salt stress in mango tree.

  9. Studies on the performance of TiO{sub 2} thin films as protective layer to chlorophyll in Ocimum tenuiflorum L from UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Malliga, P. [Department of Physics, V.V.Vanniaperumal College for Women, Virudhunagar – 626001 (India); Selvi, B. Karunai [Department of Botany, V.V.Vanniaperumal College for Women, Virudhunagar – 626001 (India); Pandiarajan, J.; Prithivikumaran, N. [Nanoscience Lab, Department of Physics, VHNSN College, Virudhunagar – 626001 (India); Neyvasagam, K., E-mail: srineyvas@yahoo.co.in [Department of Physics, The Madura College, Madurai - 625011 (India)

    2015-06-24

    Thin films of TiO{sub 2} were prepared on glass substrates using sol-gel dip coating technique. The films with 10 coatings were prepared and annealed at temperatures 350°C, 450°C and 550°C for 1 hour in muffle furnace. The annealed films were characterized by X – Ray diffraction (XRD), UV – Visible, AFM, Field Effect Scanning Electron Microscopy (FESEM) and EDAX studies. Chlorophyll has many health benefits due to its structural similarity to human blood and its good chelating ability. It has antimutagenic and anticarcinogenic properties. UV light impairs photosynthesis and reduces size, productivity, and quality in many of the crop plant species. Increased exposure of UV light reduces chlorophyll contents a, b and total content in plants. Titanium Dioxide (TiO{sub 2}) is a wide band gap semiconductor and efficient light harvester. TiO{sub 2} has strong UltraViolet (UV) light absorbing capability. Here, we have studied the performance of TiO{sub 2} thin films as a protective layer to the chlorophyll contents present in medicinal plant, tulsi (Ocimum tenuiflorum L) from UV radiation. The study reveals that crystallite size increases, transmittance decreases and chlorophyll contents increases with increase in annealing temperature. This study showed that TiO{sub 2} thin films are good absorber of UV light and protect the chlorophyll contents a, b and total content in medicinal plants.

  10. Studies on the performance of TiO2 thin films as protective layer to chlorophyll in Ocimum tenuiflorum L from UV radiation

    Science.gov (United States)

    Malliga, P.; Selvi, B. Karunai; Pandiarajan, J.; Prithivikumaran, N.; Neyvasagam, K.

    2015-06-01

    Thin films of TiO2 were prepared on glass substrates using sol-gel dip coating technique. The films with 10 coatings were prepared and annealed at temperatures 350°C, 450˚C and 550˚C for 1 hour in muffle furnace. The annealed films were characterized by X - Ray diffraction (XRD), UV - Visible, AFM, Field Effect Scanning Electron Microscopy (FESEM) and EDAX studies. Chlorophyll has many health benefits due to its structural similarity to human blood and its good chelating ability. It has antimutagenic and anticarcinogenic properties. UV light impairs photosynthesis and reduces size, productivity, and quality in many of the crop plant species. Increased exposure of UV light reduces chlorophyll contents a, b and total content in plants. Titanium Dioxide (TiO2) is a wide band gap semiconductor and efficient light harvester. TiO2 has strong UltraViolet (UV) light absorbing capability. Here, we have studied the performance of TiO2 thin films as a protective layer to the chlorophyll contents present in medicinal plant, tulsi (Ocimum tenuiflorum L) from UV radiation. The study reveals that crystallite size increases, transmittance decreases and chlorophyll contents increases with increase in annealing temperature. This study showed that TiO2 thin films are good absorber of UV light and protect the chlorophyll contents a, b and total content in medicinal plants.

  11. Studies on the performance of TiO2 thin films as protective layer to chlorophyll in Ocimum tenuiflorum L from UV radiation

    International Nuclear Information System (INIS)

    Thin films of TiO2 were prepared on glass substrates using sol-gel dip coating technique. The films with 10 coatings were prepared and annealed at temperatures 350°C, 450°C and 550°C for 1 hour in muffle furnace. The annealed films were characterized by X – Ray diffraction (XRD), UV – Visible, AFM, Field Effect Scanning Electron Microscopy (FESEM) and EDAX studies. Chlorophyll has many health benefits due to its structural similarity to human blood and its good chelating ability. It has antimutagenic and anticarcinogenic properties. UV light impairs photosynthesis and reduces size, productivity, and quality in many of the crop plant species. Increased exposure of UV light reduces chlorophyll contents a, b and total content in plants. Titanium Dioxide (TiO2) is a wide band gap semiconductor and efficient light harvester. TiO2 has strong UltraViolet (UV) light absorbing capability. Here, we have studied the performance of TiO2 thin films as a protective layer to the chlorophyll contents present in medicinal plant, tulsi (Ocimum tenuiflorum L) from UV radiation. The study reveals that crystallite size increases, transmittance decreases and chlorophyll contents increases with increase in annealing temperature. This study showed that TiO2 thin films are good absorber of UV light and protect the chlorophyll contents a, b and total content in medicinal plants

  12. The Magnesium Chelation Step in Chlorophyll Biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Gregory L. Dilworth, Ph.D Chemical Sciences, Geosciences and Biosciences Division Office of Basis Energy Sciences, greg.dilworth@science.doe.gov

    2001-01-17

    The progress described in this report encompasses work supported by DOE grant DE-FG09-89ER13989 for the period 2/15/92 to the present 6/14/94. The goals of the project were to continue investigating the enzymology of Mg-chelatase and to investigate the co-regulation of heme and chlorophyll formation in intact plastids. During this period the laboratory had additional support (two years) from USDA to investigate heme metabolism in chloroplasts. This report is arranged so that the progress is described by reference to manuscripts which are published, under review or in preparation.

  13. Photo-bleaching response in chlorophyll solutions

    International Nuclear Information System (INIS)

    Photo-excitation processes were investigated in chlorophyll solutions by irradiation with UV light sources. Photo-excited bulk effects during the bleaching experiments were diagnosed. The optical diagnostic was expressed by a Beer-Lambert matrix formulation and applied to the experimental results. The chromophores evaluated optical cross-section was 10-15 cm2 and the optical absorption coefficient dynamic variation was fitted to a simple reaction rate model. The bleaching rates were expressed by this model and fitted to the experimental data

  14. Effects of maturity on chlorophyll-related absorption in nectarines, measured by non-destructive time-resolved reflectance spectroscopy

    NARCIS (Netherlands)

    Tijskens, L.M.M.; Eccher Zerbini, P.C.; Vanoli, M.; Jacob, S.; Grassi, M.; Cebeddu, R.; Spinelli, L.; Torricelli, A.

    2006-01-01

    The ripening of fruits like nectarines and peaches is characterised by the decrease in chlorophyll content or colour of the fruit flesh. However, measuring the colour of fruit flesh is usually not conducted, as there is a lack of suitable techniques. Time-Resolved Reflectance Spectroscopy (TRS) is a

  15. Isolation of chlorophylls from stinging nettle (Urtica dioica L.)

    OpenAIRE

    Hojnik, Maša; Škerget, Mojca; Knez, Željko

    2012-01-01

    This study was aimed to assess the feasibility of extracting chlorophylls fromstinging nettle (Urtica dioica L.) by solvent extraction. In preliminary, the investigation concerned three parts of raw material (leaves, stalk and whole plant), different preservation techniques (blanching and drying) and different storage temperatures of preserved material ( |20 C for blanched and 4 C for dried sample). Extracts were analysed for chlorophyll A and chlorophyll B, respectively, by means of HPLC met...

  16. In vitro complexes of copper and zinc with chlorophyll

    OpenAIRE

    JELENA PETROVIC; GORAN NIKOLIC; DEJAN MARKOVIC

    2006-01-01

    Complexes of copper and zinc with chlorophyll, the major photosynthesis pigment, were studied by Vis, FTIR and fluorescence spectroscopy. Two types of complexes were recognized. While copper replaces the central magnesium atom of chlorophyll to form a “central” Cu–Chl complex, this was not proposed in the case of zinc. Instead, the zinc-mediated formation of a 6-membered chelate cycle fused at the periphery of the chlorophyll structure is proposed. The latter event could be ascribed to allome...

  17. Expansion Nets and Expansion Processes of Elementary Net Systems

    Institute of Scientific and Technical Information of China (English)

    曹存根

    1995-01-01

    Occurrence nets are insufficient to precisely describe executions of elementary net systems with contacts.Traditionally,S-complementation is used for removal of contacts from the systems.Although the main behavior and properties of the original elementary net systems are preserved during S-complementation,their topologies may be changed greatly.This paper introduces a new kind of nets-expansion nets-for representing behavior of elementary net systems.As shown in the paper,expansion nets are natural as well as sufficient for describing the precise behavior of elementary net systems with or without contactks.

  18. PhysioNet

    Data.gov (United States)

    U.S. Department of Health & Human Services — The PhysioNet Resource is intended to stimulate current research and new investigations in the study of complex biomedical and physiologic signals. It offers free...

  19. Deep Belief Nets for Topic Modeling

    DEFF Research Database (Denmark)

    Maaløe, Lars; Arngren, Morten; Winther, Ole

    2015-01-01

    this paper we describe large-scale content based collaborative filtering for digital publishing. To solve the digital publishing recommender problem we compare two approaches: latent Dirichlet allocation (LDA) and deep be-lief nets (DBN) that both find low-dimensional latent representations for...

  20. Comparison of green and variegated foliage plant species based on chlorophyll fluorescence parameters under different light intensities

    International Nuclear Information System (INIS)

    To compare green and variegated foliage plants namely; Hedera helix, Ardisia pusilla and Scindapsus aureus were treated under three different light intensities (2, 10 and 20 micro mol-m-2-s-1) using florescent lights for three months, and photosynthetic characteristics and chlorophyll content were measured. IMAGING-PAM chlorophyll fluorescence system was used to determine photosynthetic characteristics. The results showed that Fv/Fm (maximal PS-II quantum yield) and Y (II) (effective PS-II quantum yield) values were lower in variegated species compared to those in green species at 2 micro mol-m-2-s-1 light intensity. Although, Fv/Fm and Y (II) values in variegated S. aureus was lower than variegated H. helix, but variegated S. aureus survived and Hedera helix plants died after low light treatment. In contrast, Fv/Fm and Y (II) values were increased in green and variegated species with increasing the light intensity, except Fv/Fm value for variegated S. aureus which was slightly decreased at 20 micro mol-m-2-s-1 light intensity. The ETR (electron transport rate) value was also lower in both green and variegated species at 2 micro mol-m-2-s-1 intensity. ETR values saturated in green and variegated plants with increasing the light intensity. Higher level of chlorophyll was obtained in green species compared to variegated species for both low and high light intensity treatments. Chlorophyll content in green species decreased at 20 micro mol-m-2-s-1 light intensity, whereas in variegated species, chlorophyll content increased with increasing the light intensities. The results of chlorophyll fluorescence parameters showed that especially low light intensity created stress condition in variegated foliage plants compared to green plants, and affected the normal growth and development. (author)

  1. Programming NET 35

    CERN Document Server

    Liberty, Jesse

    2009-01-01

    Bestselling author Jesse Liberty and industry expert Alex Horovitz uncover the common threads that unite the .NET 3.5 technologies, so you can benefit from the best practices and architectural patterns baked into the new Microsoft frameworks. The book offers a Grand Tour" of .NET 3.5 that describes how the principal technologies can be used together, with Ajax, to build modern n-tier and service-oriented applications. "

  2. Remote sensing of terrestrial chlorophyll fluorescence from space

    OpenAIRE

    Frankenberg, Christian; Berry, Joseph; Guanter, Luis; JOINER Joanna

    2013-01-01

    High-resolution spectrometers enable new avenues in global carbon cycle research, including the first accurate retrievals of chlorophyll fluorescence from space as an indicator of photosynthetic activity.

  3. The magnesium chelation step in chlorophyll biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, J.D.

    1991-01-01

    The biogenesis of energy transducing membranes requires the coordinate synthesis of prosthetic groups, proteins and lipids. Two of the major prosthetic groups, chlorophyll and heme, share a common biosynthetic pathway that diverges at the point of metal insertion into protoporphyrin IX. Insertion of iron leads to heme, while insertion of magnesium leads to chlorophyll. The Mg-chelatase from intact cucumber chloroplasts has been characterized with regard to substrate specificity, regulation, ATP requirement, and a requirement for intact chloroplasts. Mg-chelatase was isolated from maize, barley and peas and characterized in order to circumvent the intact chloroplast requirement of cucumber Mg-chelatase. Pea Mg-chelatase activity is higher than cucumber Mg-chelatase activity, and lacks the requirement for intact chloroplasts. Studies on isolated pea Mg-chelatase have shown more cofactors are required for the reaction than are seen with ferrochelatase, indicating a greater opportunity for regulatory control of this pathway. Two of the cofactors are proteins, and there appears to be a requirement for a protease-sensitive component which is outside the outer envelope. We are developing a continuous spectrophotometric assay for Mg-chelatase activity, and an assay for free heme which has shown heme efflux from intact chloroplasts. 18 refs. (MHB)

  4. Chlorophyll evaluation methods in Brachiaria brizantha brs Piatã added with poultry litter compost

    Directory of Open Access Journals (Sweden)

    Alexandre Antonio Pasqualini

    2013-12-01

    Full Text Available One of the major limitations for pastures high production is the low fertility of tropical soils. In general, the nutrient reposition through chemical fertilizers increases the cost of production and can unbalance the plant besides the environment pollution. Recycling solid residues from agribusiness is a sustainable alternative for farmers. Among the residues, the poultry litter (PL aerobically fermented is a very good bio fertilizer for pastures. The Piatã Grass (Brachiaria brizantha is a new option for the pasture market and can be used for bovine, equine or ovine. The fast diagnosis of the nutritional stage of this plant, based upon portable methods as the Dualex, measuring leaf light reflectance is a practical alternative.  By this way,  it is possible to offer to the herd high nutritional food, correcting eventual shortage, mainly nitrogen. Nitrogen nutrition is directely related to chlorophyll content in the leaf blade. This study aimed to verify the effects of doses of PL over total chlorophyll, in comparison to two methods of evaluation: Dualex Scientific 4.0 and Spectrophotometer Analysis according to Lichtenthaler & Wellburn (1983. The experiment was conducted in greenhouse conditions, at IZ, Nova Odessa, with a Haplortox soil, between May and July, 2013. Treatments consisted of five compost doses (PL: 0, 20, 40, 60 and 120 Mg ha-1, with the following chemical composition (%: 2.88 of N, 3.85 of P2O5, 2.50 of K2O, 9.06 of Ca and 1.16 of Mg. The experimental design was on randomized blocks with five replications. Data were analyzed using the GLM procedure of the SAS program. Chlorophyll data were taken from the third medium of the leaf blade from a third of the expanded leaf from the apical using the Dualex. At the same time, samples were harvested for the Spectrophotometer analyses according to methodology described by Lichtenthaler & Wellburn (1983. Total Chlorophyll amounts were increased with the higher doses of PL, adjusting

  5. Effects of NaCl Stress on Chlorophyll Fluorescence Parameters in Cinnamomum japonicum var. chenii%NaCl胁迫对普陀樟叶绿素荧光参数的影响

    Institute of Scientific and Technical Information of China (English)

    李影丽; 汪奎宏; 杜国坚; 许利群; 杨华; 肖纪军

    2008-01-01

    [Objective] Study on the changes of chlorophyll fluorescence parameters in Cinnamomum japonicum var. chenii under NaCl stress. [Method] The seedling growth increment, chlorophyll content and chlorophyll fluorescence parameters in leaves of 1-year old Cinnamomum japonicum var. chenii were investigated in field experiment. [Result] Under NaCl stress, seedling growth increment reduced and the chlorophyll content decreased to a stable value; changes of Fv/Fm and Fv/Fo showed identical increasing trend and double peak type. With the aggravation of salt stress, most variations were ob- served in Fo, correlations among chlorophyll fluorescence parameters presented "rise-drop" trend (in the treatment of 7 g/L NaCl). [Condusion] Cinna-momum japonicum var. chenii is endowed with strong salt resistance and wide adaptability.

  6. The role of chlorophyll b in photosynthesis: Hypothesis

    Directory of Open Access Journals (Sweden)

    Park Hyoungshin

    2001-10-01

    Full Text Available Abstract Background The physico-chemical properties of chlorophylls b and c have been known for decades. Yet the mechanisms by which these secondary chlorophylls support assembly and accumulation of light-harvesting complexes in vivo have not been resolved. Presentation Biosynthetic modifications that introduce electronegative groups on the periphery of the chlorophyll molecule withdraw electrons from the pyrrole nitrogens and thus reduce their basicity. Consequently, the tendency of the central Mg to form coordination bonds with electron pairs in exogenous ligands, a reflection of its Lewis acid properties, is increased. Our hypothesis states that the stronger coordination bonds between the Mg atom in chlorophyll b and chlorophyll c and amino acid sidechain ligands in chlorophyll a/b- and a/c-binding apoproteins, respectively, enhance their import into the chloroplast and assembly of light-harvesting complexes. Testing Several apoproteins of light-harvesting complexes, in particular, the major protein Lhcb1, are not detectable in leaves of chlorophyll b-less plants. A direct test of the hypothesis – with positive selection – is expression, in mutant plants that synthesize only chlorophyll a, of forms of Lhcb1 in which weak ligands are replaced with stronger Lewis bases. Implications The mechanistic explanation for the effects of deficiencies in chlorophyll b or c points to the need for further research on manipulation of coordination bonds between these chlorophylls and chlorophyll-binding proteins. Understanding these interactions will possibly lead to engineering plants to expand their light-harvesting antenna and ultimately their productivity.

  7. New vegetation indices for remote measurement of chlorophylls based on leaf directional reflectance spectra.

    Science.gov (United States)

    Maccioni, A; Agati, G; Mazzinghi, P

    2001-08-15

    Directional reflectance (R) spectra from 380 to 780 nm for nadir illuminated leaves of four different plants (croton, Codiaeum variegatum; spotted eleagnus, Eleagnus pungens Maculata; Japanese pittosporum, Pittosporum tobira and Benjamin fig, Ficus benjamina Starlight) were acquired at a viewing angle of 30 degrees from the nadir direction. Chlorophyll-a and -b content of leaves covered a range of 1-60 and 0.5-21 microg/cm(2), respectively. In contrast with previous results from hemispherical reflectance measurements, directional reflectance data does not correlate well with chlorophyll concentration. This is mainly due to the external reflectance (R(E)) at the leaf epidermis, caused by the mismatch of the refractive index at the air-epidermis and epidermis-inner layer boundary. The external reflectance can be identified with the blue flat reflectance between 380 and 480 nm. The inner reflectance (R(I)), obtained by subtracting the external reflectance from the measured spectra, was found to be linearly related to the logarithm of the chlorophyll content. Good fitting of the log (Chl) versus R(I)(lambda) curves were obtained for R(I) in the green band (around 550 nm) and close to the inflection point in the red edge (around 700 nm). The coefficient of determination, r(2), of curve fitting improved (up to 0.97) when the normalised inner reflectance NR(I)(lambda)=R(I)(lambda)/R(I)(lambda(0)), with lambda(0)>or=750 nm, was used instead of the absolute reflectance. The best indices for Chl, Chl-a and Chl-b determination were R(I)(542)/R(I)(750), R(I)(706)/R(I)(750) and R(I)(556)/R(I)(750), respectively. However, since the content of Chl-a relative to Chl-b was almost constant for the plants investigated, the two last indices must be further validated on leaves with a high variability in the Chl-a:Chl-b ratio. The error in the determination of chlorophyll content was found to be of the order of 10%. This value was lower than those obtained by applying the vegetation

  8. Relationship between leaf optical properties, chlorophyll fluorescence and pigment changes in senescing Acer saccharum leaves.

    Science.gov (United States)

    Junker, Laura Verena; Ensminger, Ingo

    2016-06-01

    The ability of plants to sequester carbon is highly variable over the course of the year and reflects seasonal variation in photosynthetic efficiency. This seasonal variation is most prominent during autumn, when leaves of deciduous tree species such as sugar maple (Acer saccharum Marsh.) undergo senescence, which is associated with downregulation of photosynthesis and a change of leaf color. The remote sensing of leaf color by spectral reflectance measurements and digital repeat images is increasingly used to improve models of growing season length and seasonal variation in carbon sequestration. Vegetation indices derived from spectral reflectance measurements and digital repeat images might not adequately reflect photosynthetic efficiency of red-senescing tree species during autumn due to the changes in foliar pigment content associated with autumn phenology. In this study, we aimed to assess how effectively several widely used vegetation indices capture autumn phenology and reflect the changes in physiology and photosynthetic pigments during autumn. Chlorophyll fluorescence and pigment content of green, yellow, orange and red leaves were measured to represent leaf senescence during autumn and used as a reference to validate and compare vegetation indices derived from leaf-level spectral reflectance measurements and color analysis of digital images. Vegetation indices varied in their suitability to track the decrease of photosynthetic efficiency and chlorophyll content despite increasing anthocyanin content. Commonly used spectral reflectance indices such as the normalized difference vegetation index and photochemical reflectance index showed major constraints arising from a limited representation of gradual decreases in chlorophyll content and an influence of high foliar anthocyanin levels. The excess green index and green-red vegetation index were more suitable to assess the process of senescence. Similarly, digital image analysis revealed that vegetation

  9. An Integrated Protein Chemistry Laboratory: Chlorophyll and Chlorophyllase

    Science.gov (United States)

    Arkus, Kiani A. J.; Jez, Joseph M.

    2008-01-01

    Chlorophyll, the most abundant pigment in nature, is degraded during normal plant growth, when leaves change color, and at specific developmental stages. Chlorophyllase catalyzes the first chemical reaction in this process, that is, the hydrolysis of chlorophyll into chlorophyllide. Here, we describe a series of laboratory sessions designed to…

  10. Modulated Chlorophyll "a" Fluorescence: A Tool for Teaching Photosynthesis

    Science.gov (United States)

    Marques da Silva, Jorge; Bernardes da Silva, Anabela; Padua, Mario

    2007-01-01

    "In vivo" chlorophyll "a" fluorescence is a key technique in photosynthesis research. The recent release of a low cost, commercial, modulated fluorometer enables this powerful technology to be used in education. Modulated chlorophyll a fluorescence measurement "in vivo" is here proposed as a tool to demonstrate basic photosynthesis phenomena to…

  11. Investigating the control of chlorophyll degradation by genomic correlation mining

    Science.gov (United States)

    Chlorophyll degradation is an intricate process that is critical in a variety of plant tissues at different times during the plant life cycle. Many of the photoactive chlorophyll degradation intermediates are exceptionally cytotoxic necessitating that the pathway be carefully coordinated and regulat...

  12. A model for chlorophyll fluorescence and photosynthesis at leaf scale

    NARCIS (Netherlands)

    Tol, van der C.; Verhoef, W.; Rosema, A.

    2009-01-01

    This paper presents a leaf biochemical model for steady-state chlorophyll fluorescence and photosynthesis of C3 and C4 vegetation. The model is a tool to study the relationship between passively measured steady-state chlorophyll fluorescence and actual photosynthesis, and its evolution during the da

  13. Chlorophyll in tomato seeds: marker for seed performance?

    NARCIS (Netherlands)

    Suhartanto, M.R.

    2002-01-01

    Using Xe-PAM, laser induced fluorometry and high performance liquid chromatography we found that chlorophyll was present in young tomato (cv. Moneymaker) seeds and was degraded during maturation. Fluorescence microscopy and imaging showed that the majority of chlorophyll is located in the seed coat

  14. Influence of selected abiotic factors on the decomposition of chlorophylls

    Directory of Open Access Journals (Sweden)

    Gra¿yna Kowalewska

    2001-09-01

    Full Text Available The paper presents the results of experiments to determine the influence of selected physico-chemical factors - oxygen, visible light and temperature - on the decomposition of (1 chlorophylls a, b and c, chlorophyll a derivatives and beta-carotene in acetone solution, and (2 chlorophyll a and beta-carotene in axenic cultures of the blue-green algae Anabaena variabilis. The results indicate that both in acetone extracts and in blue-green algae cultures these pigments were most sensitive to light and oxygen; temperatures of up to 25oC had no marked influence on these compounds. Under anoxia in acetone solution, the stability towards light decreased in the order chlorophyll a, chlorophyll b, chlorophylls c. Chlorophyll a, moreover, was less stable than its derivatives - phaeophorbides, phaeophytins, pyrophaeophytins and steryl chlorins - but more stable than beta-carotene, in the last case also in the blue-green algae cultures. Decomposition of all the pigments proceeded mainly via the breakdown of the porphyrin macrocycle, since the decomposition products were not detected in the VIS range. On the basis of these experiments one can state that while light and oxygen may have a decisive direct influence on the distribution of chlorophylls and beta-carotene in sediments, in the natural environment, temperatures of up to 25oC may have very little immediate effect.

  15. Photogeneration of charges in microcrystalline chlorophyll a

    International Nuclear Information System (INIS)

    The electric-field and temperature dependence of hole photogeneration in chlorophyll a (Chla) have been analyzed in terms of electric-field assisted thermal dissociation of charge pairs based on Onsager theory. An excellent agreement between the experimental and theoretical values of the slope-to-intercept ratio, S/I, for the plot of photogeneration efficiency vs. electric field at low field strengths provides a proof for the applicability of the Onsager approach to the photogeneration of charges in Chla. A value of 19 nm has been obtained for Coulomb capture radius, rc, from S/I. From the temperature dependence of photogeneration, the initial separation, r0, of photogenerated electron-hole has been evaluated, and has a value of 1.24 nm. This smaller r0 compared to rc leads to a feeble dissociation probability of electron-hole pairs into free carriers, and may, among other factors, explain the low power conversion efficiencies of Chla photovoltaic cells.

  16. Nonspectroscopic imaging for quantitative chlorophyll sensing

    Science.gov (United States)

    Kim, Taehoon; Kim, Jeong-Im; Visbal-Onufrak, Michelle A.; Chapple, Clint; Kim, Young L.

    2016-01-01

    Nondestructive imaging of physiological changes in plants has been intensively used as an invaluable tool for visualizing heterogeneous responses to various types of abiotic and biotic stress. However, conventional approaches often have intrinsic limitations for quantitative analyses, requiring bulky and expensive optical instruments for capturing full spectral information. We report a spectrometerless (or spectrometer-free) reflectance imaging method that allows for nondestructive and quantitative chlorophyll imaging in individual leaves in situ in a handheld device format. The combination of a handheld-type imaging system and a hyperspectral reconstruction algorithm from an RGB camera offers simple instrumentation and operation while avoiding the use of an imaging spectrograph or tunable color filter. This platform could potentially be integrated into a compact, inexpensive, and portable system, while being of great value in high-throughput phenotyping facilities and laboratory settings.

  17. Influence of ambient sulphur dioxide on chlorophyll

    International Nuclear Information System (INIS)

    For the evaluation of the injury due to SO2 from Indraprashtha (IP) Thermal Power Plant, eight species of trees were selected. Experiment was divided in two sections. Section one include transplanted tree saplings of Bauhinia variegata, Delonix regia, Flcus benghalensis, Putranjiwa roxburghii, Morus indica, Polyalthia longifolia, Leucaena leucocephala and Tabernaemontana coronaria. Here one set of plants was transplanted to polluted site of IP and other set was maintained at non polluted site of Jawaharlal Nehru University (Ecological Nursery). Second section of the study have naturally growing trees of the same species in the vicinity of the transplanted plants. Findings of the present study show that tree species were not safe at polluted site. Maximum chlorophyll reduction occurred in Bauhinia variegata, that is 32.05% (transplanted saplings). In naturally growing trees up to 35.70% reduction was seen in B. variegata. (author). 11 refs., 2 tabs

  18. Biological Petri Nets

    CERN Document Server

    Wingender, E

    2011-01-01

    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  19. Science Letters: A modified chlorophyll absorption continuum index for chlorophyll estimation

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-hua; HUANG Jing-feng; WANG Fu-min; WANG Xiu-zhen; YI Qiu-xiang; WANG Yuan

    2006-01-01

    There is increasing interest in using hyperspectral data for quantitative characterization of vegetation m spatial and temporal scopes. Many spectral indices are being developed to improve vegetation sensitivity by minimizing the background influence. The chlorophyll absorption continuum index (CACI) is such a measure to calculate the spectral continuum on which the analyses are based on the area of the troughs spanned by the spectral continuum. However, different values of CACI were obtained in this method because different positions of continuums were determined by different users. Furthermore, the sensitivity of CACI to agronomic parameters such as green leaf chlorophyll density (GLCD) has been reduced because the fixed positions of continuums are determined when the red edge shifted with the change in GLCD. A modified chlorophyll absorption continuum index (MCACI) is presented in this article. The red edge inflection point (REIP) replaces the maximum reflectance point (MRP) in near-infrared (NIR) shoulder on the CACI continuum. This MCACI has been proved to increase the sensitivity and predictive power of GLCD.

  20. Photochemical reactions of chlorophyll in dehydrated photosystem II: two chlorophyll forms (680 and 700 nm).

    Science.gov (United States)

    Heber, Ulrich; Shuvalov, Vladimir A

    2005-06-01

    Lichens and phototolerant poikilohydric mosses differ from spinach leaves, fern fronds or photosensitive mosses in that they show strongly decreased Fo chlorophyll fluorescence after drying. This desiccation-induced fluorescence loss is rapidly reversible under rehydration. Fluorescence emission from Photosystem II at 685 nm was decreased more strongly by dehydration than 720 nm emission. Reaction centers of Photosystem II lose activity on dehydration and regain it on hydration. Heating of desiccated lichens increased Fo chlorophyll fluorescence. The activation energy for the reversible part of the temperature-dependent fluorescence increase was 0.045 eV, which corresponds to the energy difference between the 680 and 697 nm absorption bands. In desiccated chlorolichens such as Parmelia sulcata, heating induces the appearance of positive variable fluorescence related to the reversible reduction of QA due to overcoming the energy barrier. This is interpreted to provide information on the mechanism of photoprotection: energy is dissipated by changing Chl680 or P680 into a chlorophyll form, which absorbs at 700 nm and emits light at 720 nm (Chl-720 or P680(700)) with a low quantum yield. Dissipation of light energy in this trap is activated by desiccation. PMID:16049759

  1. Coloured Petri Nets

    CERN Document Server

    Jensen, Kurt

    2009-01-01

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. This book introduces the constructs of the CPN modelling language and presents the related analysis methods. It provides a comprehensive road map for the practical use of CPN.

  2. Safety nets or straitjackets?

    DEFF Research Database (Denmark)

    Ilsøe, Anna

    2012-01-01

    Does regulation of working hours at national and sector level impose straitjackets, or offer safety nets to employees seeking working time flexibility? This article compares legislation and collective agreements in the metal industries of Denmark, Germany and the USA. The industry has historically...

  3. Game Theory .net.

    Science.gov (United States)

    Shor, Mikhael

    2003-01-01

    States making game theory relevant and accessible to students is challenging. Describes the primary goal of GameTheory.net is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…

  4. Net4Care platform

    DEFF Research Database (Denmark)

    2012-01-01

    , that in turn enables general practitioners and clinical staff to view observations. Use the menus above to explore the site's information resources. To get started, follow the short Hello, World! tutorial. The Net4Care project is funded by The Central Denmark Region and EU via Caretech Innovation....

  5. Neuronal nets in robotics

    International Nuclear Information System (INIS)

    The paper gives a generic idea of the solutions that the neuronal nets contribute to the robotics. The advantages and the inconveniences are exposed that have regarding the conventional techniques. It also describe the more excellent applications as the pursuit of trajectories, the positioning based on images, the force control or of the mobile robots management, among others

  6. Effect of Chlorocholine Chloride on Chlorophyll, Photosynthesis, Soluble Sugar and Flavonoids of Ginkgo biloba

    Directory of Open Access Journals (Sweden)

    Weiwei ZHANG

    2013-05-01

    Full Text Available The flavonoids content determines the quality characteristics of Ginkgo biloba extract that could be increased by using of plant growth regulators. The objective of study was to investigate the effect of chlorocholine chloride (CCC, an anti-gibberellin growth retardant, on photosynthesis, chlorophyll, soluble sugar, total amino acids and phenylalanine contents, flavonoid accumulation, and flavonoids enzyme activity in G. biloba leaves. The ginkgo seedlings were grown in the greenhouse conditions with foliar applications of 0 (control, 0.5, 1.0 and 2.0 g l-1 CCC. Results showed that 0.5, 1.0 and 2.0 g l-1 CCC treatments significantly increased photosynthetic rates of leaves, the contents of chlorophyll, soluble sugar, total amino acids and phenylalnine in ginkgo leaves. Total polyphenols, flavonoids, anthocyanins content, phenylalanine ammonia-lyase (PAL, chalcone synthase (CHS and chalcone isomerase (CHI activities were all significantly increased by 1.0 and 2.0 g l-1 CCC treatments. Foliar treatment with CCC therefore might be a useful means of improving pharmacological properties of G. biloba leaves.

  7. Regional ocean-colour chlorophyll algorithms for the Red Sea

    KAUST Repository

    Brewin, Robert J.W.

    2015-05-18

    The Red Sea is a semi-enclosed tropical marine ecosystem that stretches from the Gulf of Suez and Gulf of Aqaba in the north, to the Gulf of Aden in the south. Despite its ecological and economic importance, its biological environment is relatively unexplored. Satellite ocean-colour estimates of chlorophyll concentration (an index of phytoplankton biomass) offer an observational platform to monitor the health of the Red Sea. However, little is known about the optical properties of the region. In this paper, we investigate the optical properties of the Red Sea in the context of satellite ocean-colour estimates of chlorophyll concentration. Making use of a new merged ocean-colour product, from the European Space Agency (ESA) Climate Change Initiative, and in situ data in the region, we test the performance of a series of ocean-colour chlorophyll algorithms. We find that standard algorithms systematically overestimate chlorophyll when compared with the in situ data. To investigate this bias we develop an ocean-colour model for the Red Sea, parameterised to data collected during the Tara Oceans expedition, that estimates remote-sensing reflectance as a function of chlorophyll concentration. We used the Red Sea model to tune the standard chlorophyll algorithms and the overestimation in chlorophyll originally observed was corrected. Results suggest that the overestimation was likely due to an excess of CDOM absorption per unit chlorophyll in the Red Sea when compared with average global conditions. However, we recognise that additional information is required to test the influence of other potential sources of the overestimation, such as aeolian dust, and we discuss uncertainties in the datasets used. We present a series of regional chlorophyll algorithms for the Red Sea, designed for a suite of ocean-colour sensors, that may be used for further testing.

  8. Effectiveness of Chlorophyll Meter Measurement in Winter Wheat at Field Scale Level

    Directory of Open Access Journals (Sweden)

    Lukas Vojtěch

    2014-07-01

    Full Text Available This paper examines the relationship among chlorophyll meter Yara N-Tester readings, nutrition status and growth parameters (leaf area index (LAI, plant height of the winter wheat plants. Data used in this study were collected in 2010 from two fields located in the Czech Republic (area 52 and 38 ha from different farms, both with uniform and conventional crop management. The monitoring of crop stands was done at growth stage BBCH 30 in a regular sampling grid with 150 m distance between points (27 and 18 points. At each sampling point, the plant height, LAI (Delta-T SunScan and the chlorophyll concentration (Yara N-Tester were recorded. Plant samples were taken to analyse the content of main nutrients (N, P, K, Mg, Ca and S. The results of plant analysis showed that both fields were in different nutrition status: one in a correct status and another had a complex nutritional deficit (K, Ca and N. Linear regressions and ANOVA proved that under a multiple nutritional deficit, N-Tester readings responded to the growth of the crop, while in the adequate nutritional conditions the sensitivity of N-Tester to the variation in the nitrogen concentration is lower. The relationships between crop parameters and chlorophyll meter readings are not generalisable and thus the interpretation of N-Tester results has to be done separately for each field.

  9. In situ hyperspectral data analysis for pigment content estimation of rice leaves

    Institute of Scientific and Technical Information of China (English)

    程乾; 黄敬峰; 王秀珍; 王人潮

    2003-01-01

    Analyses of the correlation between hyperspectral reflectance and pigment content including chlorophyll-a, chlorophyll-b and carotenoid of leaves in different sites of rice were reported in this paper. The hyperspectral reflectance of late rice during the whole growing season was measured using a Spectroradiometer with spectral range of 350-1050 nm and resolution of 3 nm. The chlorophyll-a, chlorophyll-b and carotenoid contents in rice leaves in rice fields to which different levels of nitrogen were applied were measured. The chlorophyll-a content of upper leaves was well correlated with the spectral variables. However, the correlation between both chlorophyll-b and caroteniod and the spectral variables was far from that of chlorophyll-a. The potential of hyperspectral reflectance measurement for estimating chlorophyll-a of upper leaves was evaluated using univariate correlation and multivariate regression analysis methods with different types of predictors. This study showed that the most suitable estimated model of chlorophyll-a of upper leaves was obtained by using some hyperspectral variables such as SDr, SDb and their integration.

  10. Photoinduced electron transfer of chlorophyll in lipid bilayer system

    Indian Academy of Sciences (India)

    D K Lee; K W Seo; Y S Kang

    2002-12-01

    Photoinduced electron transfer from chlorophyll- through the interface of dipalmitoylphosphatidylcholine (DPPC) headgroup of the lipid bilayers was studied with electron magnetic resonance (EMR). The photoproduced radicals were identified with electron spin resonance (ESR) and radical yields of chlorophyll- were determined by double integration ESR spectra. The formation of vesicles was identified by changes in measured max values from diethyl ether solutions to vesicles solutions indirectly, and observed directly with SEM and TEM images. The efficiency of photosynthesis in model system was determined by measuring the amount of chlorophyll-a radical yields which were obtained from integration of ESR spectra.

  11. Chlorophyll derivatives for pest and disease control: Are they safe?

    Energy Technology Data Exchange (ETDEWEB)

    Azizullah, Azizullah, E-mail: azizswabi@gmail.com; Murad, Waheed

    2015-01-15

    Chlorophyll derivatives are getting widespread acceptance among the researchers as natural photosensitizers for photodynamic control of pests and disease vectors; however, rare attention has been given to evaluation of their toxicity to non-target organisms in the environment. This perspective article highlights that chlorophyll derivatives may not be as safe as believed and can possibly pose risk to non-target organisms in the environment. We invite the attention of environmental biologists, particularly ecotoxicologists, to contribute their role in making the application of chlorophyll derivatives more environmentally friendly and publicly acceptable.

  12. Chlorophyll derivatives for pest and disease control: Are they safe?

    International Nuclear Information System (INIS)

    Chlorophyll derivatives are getting widespread acceptance among the researchers as natural photosensitizers for photodynamic control of pests and disease vectors; however, rare attention has been given to evaluation of their toxicity to non-target organisms in the environment. This perspective article highlights that chlorophyll derivatives may not be as safe as believed and can possibly pose risk to non-target organisms in the environment. We invite the attention of environmental biologists, particularly ecotoxicologists, to contribute their role in making the application of chlorophyll derivatives more environmentally friendly and publicly acceptable

  13. Changes of Photosystem Ⅱ Electron Transport in the Chlorophyll-deficient Oilseed Rape Mutant Studied by Chlorophyll Fluorescence and Thermoluminescence

    Institute of Scientific and Technical Information of China (English)

    Jun-Wei Guo; Jin-Kui Guo; Yun Zhao; Lin-Fang Du

    2007-01-01

    The photosystem Ⅱ (PSII) complex of photosynthetic membranes comprises a number of chlorophyll-binding proteins that are important to the electron flow. Here we report that the chlorophyll b-deficient mutant has de creased the amount of light-harvesting complexes with an increased amount of some core polypeptides of PSII,including CP43 and CP47. By means of chlorophyll fluorescence and thermoluminescence, we found that the ratio of Fv/Fm, qP and electron transport rate in the chlorophyll b-deficient mutant was higher compared to the wild type.In the chlorophyll b-deficient mutant, the decay of the primary electron acceptor quinones (QA-) reoxidation was decreased, measured by the fluorescence. Furthermore, the thermolumlnescence studies in the chlorophyll b deficient mutant showed that the B band (S2/S3QB-) decreased slightly and shifted up towards higher temperatures.In the presence of dichlorophenyl-dimethylurea, which is inhibited in the electron flow to the second electron acceptor quinines (QB) at the PSII acceptor side, the maximum of the Q band (S2QA-) was decreased slightly and shifted down to lower temperatures, compared to the wild type. Thus, the electron flow within PSll of the chlorophyll b-deficient mutant was down-regulated and characterized by faster oxidation of the primary electron acceptor quinine QA- via forward electron flow and slower reduction of the oxidation S states.

  14. SolNet

    DEFF Research Database (Denmark)

    Jordan, Ulrike; Vajen, Klaus; Bales, Chris;

    2014-01-01

    SolNet, founded in 2006, is the first coordinated International PhD education program on Solar Thermal Engineering. The SolNet network is coordinated by the Institute of Thermal Engineering at Kassel University, Germany. The network offers PhD courses on solar heating and cooling, conference......-accompanying Master courses, placements of internships, and PhD scholarship projects. A new scholarship project, “SHINE”, was launched in autumn 2013 in the frame work of the Marie Curie program of the European Union (Initial Training Network, ITN). 13 PhD-scholarships on solar district heating, solar heat for...... industrial processes, as well as sorption stores and materials started in December 2013. Additionally, the project comprises a training program with five PhD courses and several workshops on solar thermal engineering that will be open also for other PhD students working in the field. The research projects...

  15. Remote sensing of near-infrared chlorophyll fluorescence from space in scattering atmospheres: implications for its retrieval and interferences with atmospheric CO2 retrievals

    OpenAIRE

    J. McDuffie; L. Guanter; C. O'Dell; C. Frankenberg

    2012-01-01

    With the advent of dedicated greenhouse gas space-borne spectrometers sporting high resolution spectra in the O2 A-band spectral region (755–774 nm), the retrieval of chlorophyll fluorescence has become feasible on a global scale. If unaccounted for, however, fluorescence can indirectly perturb the greenhouse gas retrievals as it perturbs the oxygen absorption features. As atmospheric CO2 measurements are used to invert net fluxes at the land–atmosphere interface, a bias caused by fluore...

  16. Netted LPI radars

    OpenAIRE

    Menychtas, Charalampos.

    2011-01-01

    Approved for public release; distribution is unlimited. A significant number of Low Probability of Intercept (LPI) radars are used in various military applications, from guided weapons (such anti-ship missile), to large platforms (aircrafts, ships), to large systems (Integrated Air Defense Systems - IADS). The purpose of this thesis is to evaluate the performance of netted LPI radar systems. To do so, it commences with establishing the theoretical background for the LPI radar techniques an...

  17. BacillusRegNet

    DEFF Research Database (Denmark)

    Misirli, Goksel; Hallinan, Jennifer; Röttger, Richard;

    2014-01-01

    interactions. There is a need to develop new platform technologies that can be applied to the investigation of whole-genome datasets in an efficient and cost-effective manner. One such approach is the transfer of existing knowledge from well-studied organisms to closely-related organisms. In this paper, we...... associated BacillusRegNet website (http://bacillus.ncl.ac.uk)....

  18. NET vertical stability

    International Nuclear Information System (INIS)

    The elongated cross-section of the plasma in NET leads to vertical positional instability so that a passive and active stabilizing system is required. The passive action is performed essentially by the segmented first wall, while the active action is performed by two feedback driven toroidal bars. The performance of such a system is presented for a reference case, as well as a sensitivity analysis with respect to some parameters. (author)

  19. NET vertical stability

    International Nuclear Information System (INIS)

    The elongated cross-section of the plasma in NET leads to vertical positional instability so that a passive and active stabilizing system is required. The passive action is performed essentially by the segmented first wall, while the active action is performed by two feedback driven toroidal bars. The performance of such a system is presented here for a reference case, as well as a sensitivity analysis with respect to some parameters

  20. The NET project

    International Nuclear Information System (INIS)

    The objective of NET is to demonstrate fusion energy production in an apparatus which meets the basic design and operating requirements of a reactor, i.e.: self-sustained DT thermonuclear reactions; extended burn, possibly up to steady state; qualification and testing of components in reactor-like conditions; safe operation of a reactor-like device at significant availability; and energy extraction of high temperature heat and tritium breeding. Since NET is conceived to be the only step between JET and DEMO, it must be capable of conducting a research programme in physics as well as in reactor technology. This requirement has led to an apparatus designed to operate, in the first phase (Physics Phase), with great flexibility with respect to the accessible plasma parameters. NET adopts, as far as possible, reactor relevant technologies (e.g. superconductivity), and it includes provisions and features (e.g. remote handling, access, shielding) which would enable it, in the second phase of operation (Technology Phase), to carry out a programme of qualification and testing of components. NET will be the machine in which the physics and the technology of extended plasma burn pulses will be established. The flexibility of the apparatus therefore allows the incorporation of improvements between the two phases, in particular of the plasma facing components. As for the parameters, two sets have been defined: a reference set to carry out the predesign and to define in sufficient detail the R and D tasks to be performed by the European fusion laboratories, and an alternative set with increased plasma current capability based, however, on the same design solutions and technologies as the reference case. (author). 1 ref., 1 fig., 1 tab

  1. Remote sensing of chlorophyll fluorescence with GOSAT

    Science.gov (United States)

    Somkuti, Peter; Boesch, Hartmut; Parker, Robert

    2015-04-01

    Sun-induced chlorophyll fluorescence (Fs) emitted by plants as a by-product during photosynthesis carries information about their photosynthetic activity. It is possible to exploit space-based remote sensing measurements to retrieve the fluorescence signal and thus indirectly study carbon fluxes on a global scale. We implement a fluorescence retrieval based on the method pioneered by Frankenberg et al. (2011) into the framework of the University of Leicester Full-Physics GOSAT CO2 retrieval (UoL-FP). This physically-based approach is applied to high-resolution spectra at the edges of the O2 A-Band in the red to NIR range, that feature strong solar as well as a few weak O2 absorption lines. The fluorescence signal, which acts as an additional source, results in an in-filling of the measured solar absorption lines that are used to distinguish Fs from reflectance effects. By analysing GOSAT soundings from 2009 onwards, we examine global and regional long-term trends of Fs and compare them with parameters related to plant physiology, such as spectral vegetation indices and MODIS-derived model GPP values. Following Guanter et al. (2012) and Frankenberg et al. (2011), different regions and biomes are considered and we find that seasonal trends of both model GPP data as well as greenness indicators are well reproduced by our GOSAT-retrieved Fs.

  2. Photogeneration of charges in microcrystalline chlorophyll a

    Energy Technology Data Exchange (ETDEWEB)

    Kassi, Hassan [Scientech R and D, Inc., 2200 Rue Didbec S., Bureau 203, Trois-Rivieres, Trois-Rivieres, QC, G8Z 4H1 (Canada); Barazzouk, Said, E-mail: barazzos@uqtr.c [Groupe de Recherche en Biologie Vegetale, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, QC, G9A 5H7 (Canada); Brullemans, Marc [Groupe de Recherche en Biologie Vegetale, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, QC, G9A 5H7 (Canada); Leblanc, Roger M. [Department of Chemistry, University of Miami, P.O. Box 249118, Coral Gables, FL 33124-0431 (United States); Hotchandani, Surat [Groupe de Recherche en Biologie Vegetale, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, QC, G9A 5H7 (Canada)

    2010-07-01

    The electric-field and temperature dependence of hole photogeneration in chlorophyll a (Chla) have been analyzed in terms of electric-field assisted thermal dissociation of charge pairs based on Onsager theory. An excellent agreement between the experimental and theoretical values of the slope-to-intercept ratio, S/I, for the plot of photogeneration efficiency vs. electric field at low field strengths provides a proof for the applicability of the Onsager approach to the photogeneration of charges in Chla. A value of 19 nm has been obtained for Coulomb capture radius, r{sub c}, from S/I. From the temperature dependence of photogeneration, the initial separation, r{sub 0}, of photogenerated electron-hole has been evaluated, and has a value of 1.24 nm. This smaller r{sub 0} compared to r{sub c} leads to a feeble dissociation probability of electron-hole pairs into free carriers, and may, among other factors, explain the low power conversion efficiencies of Chla photovoltaic cells.

  3. Gas exchanges in peach palms as a function of the spad chlorophyll meter readings

    Directory of Open Access Journals (Sweden)

    Maria Luiza Sant'anna Tucci

    2011-10-01

    Full Text Available The close relationship between the chlorophyll-meters readings and the total chlorophyll and nitrogen contents in leaves, has allowed their evaluation both in annual and perennial species. Besides, some physiological events such as the CO2 assimilation have also been estimated by chlorophyll meters. This work was carried out aiming to evaluate the gas exchanges of peach palms as a function of the chlorophyll SPAD-Meter readings. Three year-old peach palms from Yurimaguas, Peru were studied in Ubatuba, SP, Brazil, spaced 2 x 1 m in area under a natural gradient of organic matter which allowed four plots to be considered, according to the peach palms leaves colors, from light yellow to dark green. The SPAD readings and the stomatal frequency of leaflets were evaluated. The photosynthetic photon flux density (PPFD, μmol m-2 s-1, the leaf temperature (Tleaf, ºC, the CO2 assimilation (A, μmol m-2 s-1, the stomatal conductance (g s, mol m-2 s-1, the transpiration (E, mmol m-2 s-1 and the intercellular CO2 concentration (Ci, μmol mol-1 were evaluated with a portable infrared gas analyzer (LCA-4, ADC BioScientific Ltd., Great Amwell, U.K.. A linear increase in the CO2 assimilation as a function of the SPAD readings (y = -0.34 + 0.19x, R² = 0.99, indicates that they can be a rapid and cheap complementary method to evaluate in peach palms some important physiological events, such as CO2 assimilation.

  4. Using WordNet for Building WordNets

    CERN Document Server

    Farreres, X; Farreres, Xavier; Rodriguez, Horacio; Rigau, German

    1998-01-01

    This paper summarises a set of methodologies and techniques for the fast construction of multilingual WordNets. The English WordNet is used in this approach as a backbone for Catalan and Spanish WordNets and as a lexical knowledge resource for several subtasks.

  5. The effect of pre-treatment, temperature and length of frozen storage on the retention of chlorophylls in frozen brassicas

    Directory of Open Access Journals (Sweden)

    Waldemar Kmiecik

    2008-06-01

    Full Text Available The investigation covered broccoli, green cauliflower and Brussels sprouts. The evaluation concerned the raw material; the material after blanching; the material after cooking; and frozen products from blanched (traditional method and cooked (modified method material, stored at –20°C and –30°C then prepared for consumption using water-cooking in the traditional method and thawing by microwave in the modified method after 0, 4, 8 and 12 months of frozen storage. Depending on the investigated sample, the vegetables prepared for consumption after 12 months of frozen storage retained total chlorophylls as follows: broccoli, 45-66% of the content in the raw material; green cauliflower, 30-45%; and Brussels sprouts, 66-78%. In comparison with the traditional method, the mean content of chlorophylls in Brussels sprouts obtained using the modified method was 16% higher; however, in broccoli the content was lower by 23% and in cauliflower by 21% on average. Lower storage temperature resulted in higher content of chlorophylls in all investigated vegetables.

  6. Arbre de Notes.Net

    OpenAIRE

    Diéguez Ruiz, Rafael

    2008-01-01

    Els objectius del projecte és que l¿estudiant utilitzi moltes de les tecnologies possibles recollides dintre d¿aquesta nova plataforma de desenvolupament, entre altres existeixen: ASP.NET, ADO.NET, Serveix Web, ...

  7. Relationship between chlorophyll-a and column primary production

    Digital Repository Service at National Institute of Oceanography (India)

    Dalal, S.G.; Bhargava, R.M.S.

    Relationship between surface chlorophyll a and column primary production has been established to help in estimating the latter more quickly and accurately. The equation derived is Primary Production, y = 0.54 Ln Chl a - 0.6. The relationship...

  8. Assessment of water pollution by airborne measurement of chlorophyll

    Science.gov (United States)

    Arvesen, J. C.; Weaver, E. C.; Millard, J. P.

    1972-01-01

    Remote measurement of chlorophyll concentrations to determine extent of water pollution is discussed. Construction and operation of radiometer to provide measurement capability are explained. Diagram of equipment is provided.

  9. Remote sensing of tidal chlorophyll-a variations in estuaries

    Science.gov (United States)

    Catts, Glenn P.; Khorram, Siamak; Cloern, James E.; Knight, Allen W.; Degloria, Stephen D.

    1985-01-01

    Simultaneous acquisition of surface chlorophyll-a concentrations for 39 samples from boats and Daedalus 1260 Multispectral Scanner data from a U-2 aircraft was conducted in the northern reaches of San Francisco Bay on 28 August 1980. These data were used to develop regression models for predicting surface chlorophyll-a concentrations over the study area for ebb-tide (8.40 a.m. P.D.T. (Pacific Daylight Time)) and flood-tide (3.10 p.m. P.D.T.) conditions. After selection of a single ‘best fitting’ model for both morning and afternoon data sets, the chlorophyll-a concentration was predicted for ebb and flood tide for the entire study area at approximately 40m × 40m resolution. The predicted spatial display of chlorophyll-a revealed a localized area of high phytoplankton biomass that has been inferred from field surveys and appears to be a common summer phenomenon.

  10. Clearance rate of the mussel Mytilus galloprovincialis. I. Response to extreme chlorophyll ranges

    OpenAIRE

    Filgueira, Ramón; Fernández-Reiriz, María José; Labarta, Uxío

    2009-01-01

    [EN] Clearance rate (CR) measurements in Mytilus galloprovincialis were determined over 16 experiments in which the mussels were exposed to diets characterized by variable chlorophyll content (0.28–104.88 μg Chla L–1) in order to: (1) establish the lower trigger level and the saturation reduction, (2) elucidate whether these thresholds were controlled by an on/off switch or by a progressive response, and (3) determine whether the experimental time exerted an effect on the CR measurem...

  11. [Effects of controlled-release fertilizer on chrysanthemum leaf chlorophyll fluorescence characteristics and ornamental quality].

    Science.gov (United States)

    Song, Xu-xu; Zheng, Cheng-shu; Sun, Xia; Ma, Hai-yan

    2011-07-01

    Taking cut flower chrysanthemum 'Baima' as test material, a pot experiment was conducted to study the effects of controlled-release fertilizer on the leaf chlorophyll fluorescence parameters, chlorophyll and nutrient contents, and ornamental quality of chrysanthemum. Under no fertilization, the maximal photochemical efficiency of PS II in dark (F(v)/F(m)), potential photochemical efficiency of PS II (F(v)/F(0)), and quantum yield of PS II electron transport (phi(PS II)) decreased significantly, compared with those under fertilization. With the application of conventional compound fertilizers CCFA (N:P:K=20:8:10) and CCFB (N:P:K= 14:14:14), the F(v)/F(m), F(v)/F(0) and phi(PS II) had a slight increase in early period (30-60 d) but a remarkable decrease in mid and later periods (75 - 120 d), compared with those under the application of controlled-release fertilizers CRFA (N:P:K = 20:8:10) and CRFB (N:P:K= 14:14:14). Under the application of CRFA, the F(v)/F(m), phi(PS II), and photochemical quenching (q(P)) had somewhat increase, as compared with the application of CRFB. The non-photochemical quenching (NPQ) under the application of CRFA and CRFB decreased significantly, compared with that under the application of CCFA and CCFB and the control. The chlorophyll content had a similar change trend with F(v)/F(m), F(v)/F(0), and phi(PS II). The leaf N, P, and K contents, flower stalk length and stalk diameter, flower diameter, and flower fresh and dry mass at harvest stage all increased under the application of CRFA and CRFB, compared with those under the application of CCFA and CCFB and the control, and the flower fresh and dry mass was significantly higher under the application of CRFA than of CRFB. This study showed that controlled-release fertilizer could improve the ornamental quality of chrysanthemum via improving the leaf chlorophyll content, photochemical transduction rate, and nutrient uptake, and CRFA had better effects than CRFB. PMID:22007449

  12. Instrumentation in Developing Chlorophyll Fluorescence Biosensing: A Review

    OpenAIRE

    Millan-Almaraz, Jesus R.; Guevara-Gonzalez, Ramon G.; Irineo Torres-Pacheco; Romero-Troncoso, Rene J.; Contreras-Medina, Luis M.; Carlos Duarte-Galvan; Fernandez-Jaramillo, Arturo A.

    2012-01-01

    Chlorophyll fluorescence can be defined as the red and far-red light emitted by photosynthetic tissue when it is excited by a light source. This is an important phenomenon which permits investigators to obtain important information about the state of health of a photosynthetic sample. This article reviews the current state of the art knowledge regarding the design of new chlorophyll fluorescence sensing systems, providing appropriate information about processes, instrumentation and electronic...

  13. Net one, net two: the primary care network income statement.

    Science.gov (United States)

    Halley, M D; Little, A W

    1999-10-01

    Although hospital-owned primary care practices have been unprofitable for most hospitals, some hospitals are achieving competitive advantage and sustainable practice operations. A key to the success of some has been a net income reporting tool that separates practice operating expenses from the costs of creating and operating a network of practices to help healthcare organization managers, physicians, and staff to identify opportunities to improve the network's financial performance. This "Net One, Net Two" reporting allows operations leadership to be held accountable for Net One expenses and strategic leadership to be held accountable for Net Two expenses. PMID:11066669

  14. Chemataxonomic researches in higher plants. XV Carotenoid and chlorophyll pigments in the leaves of Cannabis sativa L.

    Directory of Open Access Journals (Sweden)

    Gavrila NEAMTU

    1981-08-01

    Full Text Available In the leaves of Cannabis sativa L. were found the following carotenoid pigments: ?-carotene, lutein, zeaxanthin, violaxanthin, neoxanthin and ?-cryptoxanthin. The ratio between the content of ?-carotene and lutein - which are the principal foliar carotenoids - was supraunitary, a feature that might be used as a chemotaxonomic criterion. It is worth to be mentioned the relatively high content of zeaxanthin and ?-cryptoxanthin in comparison with the level of these pigments in the leaves of most higher plants. The ratio between the content of chlorophyll a and b was of 2,17.

  15. Net4Care Ecosystem Website

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Hansen, Klaus Marius; Rasmussen, Morten;

    2012-01-01

    tele-monitoring scenario in which Net4Care clients are deployed in a gateway in private homes. Medical devices then connect to these gateways and transmit their observations to a Net4Care server. In turn the Net4Care server creates valid clinical HL7 documents, stores them in a national XDS repository...

  16. Burkina Faso social safety nets

    OpenAIRE

    Cherrier, Cecile; del Ninno, Carlo; Razmara, Setareh

    2011-01-01

    This report provides an inventory of safety net programs in Burkina Faso and suggests policy measures that could increase their coverage, efficiency, and sustainability. It shows that the scope and coverage of the existing safety nets is too limited. Most interventions are small and temporary. On average, excluding subsidies, annual spending on safety nets constituted only 0.6 percent of GDP ...

  17. Net metering: zero electricity bill

    International Nuclear Information System (INIS)

    Worldwide move towards renewable energy sources, environmental concerns and decentralization of the power sector have made net metering an attractive option for power generation at small scale. This paper discusses the net metering, economical issues of renewable sources in Pakistan, technical aspects, installation suitability according to varying terrain, existing utility rules and formulation of legislation for net metering making it economically attractive. (author)

  18. Prospects for Chlorophyll Fluorescence Remote Sensing from the Orbiting Carbon Observatory-2

    Science.gov (United States)

    Frankenberg, Christian; Odell, Chris; Berry, Joseph; Guanter, Luis; Joiner, Joanna; Kohler, Philipp; Pollock, Randy; Taylor, Thomas E.

    2014-01-01

    The Orbiting Carbon Observatory-2 (OCO-2), scheduled to launch in July 2014, is a NASA mission designed to measure atmospheric CO2. Its main purpose is to allow inversions of net flux estimates of CO2 on regional to continental scales using the total column CO2 retrieved using high-resolution spectra in the 0.76, 1.6, and 2.0 nm ranges. Recently, it was shown that solar-induced chlorophyll fluorescence (SIF), a proxy for gross primary production (GPP, carbon uptake through photosynthesis), can be accurately retrieved from space using high spectral resolution radiances in the 750 nm range from the Japanese GOSAT and European GOME-2 instruments. Here, we use real OCO-2 thermal vacuum test data as well as a full repeat cycle (16 days) of simulated OCO-2 spectra under realistic conditions to evaluate the potential of OCO-2 for retrievals of chlorophyll fluorescence and also its dependence on clouds and aerosols. We find that the single-measurement precision is 0.3-0.5 Wm(exp -2)sr(exp -1) nm(exp -1) (15-25% of typical peak values), better than current measurements from space but still difficult to interpret on a single-sounding basis. The most significant advancement will come from smaller ground-pixel sizes and increased measurement frequency, with a 100-fold increase compared to GOSAT (and about 8 times higher than GOME-2). This will largely decrease the need for coarse spatial and temporal averaging in data analysis and pave the way to accurate local studies.We also find that the lack of full global mapping from the OCO-2 only incurs small representativeness errors on regional averages. Eventually, the combination of net ecosystem exchange (NEE) derived from CO2 source/sink inversions and SIF as proxy for GPP from the same satellite will provide a more process-based understanding of the global carbon cycle.

  19. Lil3 Assembles with Proteins Regulating Chlorophyll Synthesis in Barley.

    Directory of Open Access Journals (Sweden)

    Astrid Mork-Jansson

    Full Text Available The light-harvesting-like (LIL proteins are a family of membrane proteins that share a chlorophyll a/b-binding motif with the major light-harvesting antenna proteins of oxygenic photoautotrophs. LIL proteins have been associated with the regulation of tetrapyrrol biosynthesis, and plant responses to light-stress. Here, it was found in a native PAGE approach that chlorophyllide, and chlorophyllide plus geranylgeraniolpyrophosphate trigger assembly of Lil3 in three chlorine binding fluorescent protein bands, termed F1, F2, and F3. It is shown that light and chlorophyllide trigger accumulation of protochlorophyllide-oxidoreductase, and chlorophyll synthase in band F3. Chlorophyllide and chlorophyll esterified to geranylgeraniol were identified as basis of fluorescence recorded from band F3. A direct interaction between Lil3, CHS and POR was confirmed in a split ubiquitin assay. In the presence of light or chlorophyllide, geranylgeraniolpyrophosphate was shown to trigger a loss of the F3 band and accumulation of Lil3 and geranylgeranyl reductase in F1 and F2. No direct interaction between Lil3 and geranylgeraniolreductase was identified in a split ubiquitin assay; however, accumulation of chlorophyll esterified to phytol in F1 and F2 corroborated the enzymes assembly. Chlorophyll esterified to phytol and the reaction center protein psbD of photosystem II were identified to accumulate together with psb29, and APX in the fluorescent band F2. Data show that Lil3 assembles with proteins regulating chlorophyll synthesis in etioplasts from barley (Hordeum vulgare L..

  20. Does overhead irrigation with salt affect growth, yield, and phenolic content of lentil plants?

    OpenAIRE

    Giannakoula Anastasia; Ilias I.F.; Dragišić-Maksimović Jelena J.; Maksimović V.M.; Živanović Branka D.

    2012-01-01

    Overhead irrigation of lentil plants with salt (100 mM NaCl) did not have any significant impact on plant growth, while chlorophyll content and chlorophyll fluorescence parameter Fv/Fm were affected. Under such poor irrigation water quality, the malondialdehyde content in leaves was increased due to the lipid peroxidation of membranes. In seeds, the total phenolic content (TPC) was correlated to their total antioxidant capacity (TAC). High performance liquid chromatography-mass spectrom...

  1. Chlorophyll Variability in the Oligotrophic Gyres: Mechanisms, Seasonality and Trends

    Directory of Open Access Journals (Sweden)

    Sergio Romano Signorini

    2015-02-01

    Full Text Available A 16-year (1998-2013 analysis of trends and seasonal patterns was conducted for the five subtropical ocean gyres using satellite data: chlorophyll-a (Chl-a retrievals from ocean color, sea surface temperature (SST, and sea-level anomaly (SLA. Trend analysis was also performed on mixed-layer data derived from ocean model gridded temperature and salinity profiles (1998-2010. The Chl-a monthly composites were constructed from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS and Moderate-resolution Imaging Spectroradiometer (MODIS on Aqua using two different algorithms: the standard algorithm (STD that has been in use since the start of the SeaWiFS mission in 1997, and a more recently developed Ocean Color Index (OCI algorithm with improved accuracy in low Chl-a waters. Trends were obtained for all gyres using both STD and OCI algorithms, which demonstrated generally consistent results. The North Pacific, Indian Ocean, North Atlantic and South Atlantic gyres showed significant downward trends in Chl-a, while the South Pacific gyre has a much weaker upward trend with no statistical significance. Time series of satellite-derived net primary production (NPP showed downward trends for all the gyres, while all five gyres exhibited positive trends in SST and SLA. The seasonal variability of Chl-a in each gyre is tightly coupled to the variability in mixed layer depth (MLD with peak values in winter in both hemispheres when vertical mixing is more vigorous, reaching depths approaching the nutricline. On a seasonal basis, Chl-a concentrations increase when the MLD approaches or is deeper than the nutricline depth, in agreement with the concept that vertical mixing is the major driving mechanism for phytoplankton photosynthesis in the interior of the gyres. The combination of surface warming trends and biomass reduction over the 16-year period has the potential to reduce atmospheric CO2 uptake by the gyres and therefore influence the global carbon cycle.

  2. Towards a merged satellite and in situ fluorescence ocean chlorophyll product

    Directory of Open Access Journals (Sweden)

    H. Lavigne

    2011-12-01

    Full Text Available Understanding the ocean carbon cycle requires a precise assessment of phytoplankton biomass in the oceans. In terms of numbers of observations, satellite data represents the largest available data set. However, as they are limited to surface waters, they have to be merged with in situ observations. Amongst the in situ data, fluorescence profiles constitute the greatest data set available, because fluorometers operate routinely on oceanographic cruise since the seventies. Nevertheless, fluorescence is only a proxy of the Total Chlorophyll-a concentration and a data calibration is required. Calibration issues are, however, source of uncertainty and they have prevented a systematic and wide range exploitation of the fluorescence data set. In particular, very few attempts to standardize the fluorescence data bases exist. Consequently, merged estimations with other data sources (i.e. satellite are lacking.

    We propose a merging method to fill this gap. It consists firstly, in adjusting the fluorescence profile to impose a zero Chlorophyll-a concentration at depth. Secondly, each point of the fluorescence profile is then multiplied by a correction coefficient which forces the Chlorophyll-a integrated content measured on the fluorescence profile to be consistent with the concomitant ocean color observation. The method is close to the approach proposed by Boss et al. (2008 to calibrate fluorescence data of a profiling float, although important differences do exist. To develop and test our approach, in situ data from three open ocean stations (BATS, HOT and DYFAMED were used. Comparison of the so-called "satellite-corrected" fluorescence profiles with concomitant bottle derived estimations of Chlorophyll-a concentration was performed to evaluate the final error, which resulted to be of about 31 %. Comparison with the Boss et al. (2008 method, carried out on a subset of the DYFAMED data set simulating a profiling float

  3. Towards a merged satellite and in situ fluorescence ocean chlorophyll product

    Directory of Open Access Journals (Sweden)

    H. Lavigne

    2012-06-01

    Full Text Available Understanding the ocean carbon cycle requires a precise assessment of phytoplankton biomass in the oceans. In terms of numbers of observations, satellite data represent the largest available data set. However, as they are limited to surface waters, they have to be merged with in situ observations. Amongst the in situ data, fluorescence profiles constitute the greatest data set available, because fluorometers have operated routinely on oceanographic cruises since the 1970s. Nevertheless, fluorescence is only a proxy of the total chlorophyll a concentration and a data calibration is required. Calibration issues are, however, sources of uncertainty, and they have prevented a systematic and wide range exploitation of the fluorescence data set. In particular, very few attempts to standardize the fluorescence databases have been made. Consequently, merged estimations with other data sources (e.g. satellite are lacking.

    We propose a merging method to fill this gap. It consists firstly in adjusting the fluorescence profile to impose a zero chlorophyll a concentration at depth. Secondly, each point of the fluorescence profile is then multiplied by a correction coefficient, which forces the chlorophyll a integrated content measured on the fluorescence profile to be consistent with the concomitant ocean colour observation. The method is close to the approach proposed by Boss et al. (2008 to correct fluorescence data of a profiling float, although important differences do exist. To develop and test our approach, in situ data from three open ocean stations (BATS, HOT and DYFAMED were used. Comparison of the so-called "satellite-corrected" fluorescence profiles with concomitant bottle-derived estimations of chlorophyll a concentration was performed to evaluate the final error (estimated at 31%. Comparison with the Boss et al. (2008 method, using a subset of the DYFAMED data set, demonstrated that the methods have similar

  4. Boom Booom Net Radio

    DEFF Research Database (Denmark)

    Grimshaw, Mark Nicholas; Yong, Louisa; Dobie, Ian

    1999-01-01

    Internet radio is one of the growth areas of the Internet but, as this article will show, is fraught with difficulties and frustration for both the modestly-funded broadcaster (bitcaster) and the listener. The article will illustrate some of these problems by means of a short case study...... of an existing Internet radio station; Boom Booom Net Radio. Whilst necessity dictates some use of technology-related terminology, wherever possible we have endeavoured to keep such jargon to a minimum and to either explain it in the text or to provide further explanation in the appended glossary....

  5. NewsNet

    OpenAIRE

    Maffei, Lucia

    2000-01-01

    NewsNet wants to highlight the opening of a “unified law portal” as part of the plan for the E-government (http://www.governo.it/sez_dossier/neweconomy/e-government/sintesi.html) signed by the Ministers Council. The outlined overview shows from one side the creation of service portals that allow people and industries to obtain easily information on laws, and from the other the creation of helpdesks where asking the Administrations on the basis of the electronic identity card and the digital s...

  6. NetFlow-verkonvalvonta

    OpenAIRE

    Liukkonen, Mikko

    2011-01-01

    Verkonvalvonnalla on tärkeä rooli varsinkin suurten verkkojen ylläpidossa. Verkossa voi liikkua paljon erilaista dataa, joten verkonvalvojan on hyödyllistä ymmärtää, millainen verkkoliikenne kuormittaa verkkoa eniten. Perinteinen SNMP:llä toteutettu verkonvalvontajärjestelmä ei tarjoa yksityiskohtaista tietoa verkkoliikenteen sisällöstä. Cisco Systemsin kehittämällä NetFlowlla on mahdollista päästä tarkemmin käsiksi verkossa liikkuvien pakettien tietoihin ja näin ollen saada selville erilaisi...

  7. Art/Net/Work

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik; Lindstrøm, Hanne

    2006-01-01

    on the ‘network’ itself as a phenomenon and are often using technological networks as a mean of production and distribution. This changes the artistic practice and the distribution channels of art works – and the traditional notions of ‘work’, ‘origin’ and ‘rights’ are increasingly perceived as......The seminar Art|Net|Work deals with two important changes in our culture. On one side, the network has become essential in the latest technological development. The Internet has entered a new phase, Web 2.0, including the occurrence of as ‘Wiki’s’, ‘Peer-2-Peer’ distribution, user controlled...

  8. Variability of the specific fluorescence of chlorophyll in the ocean. Part 2. Fluorometric method of chlorophyll a determination

    OpenAIRE

    Miros³awa Ostrowska; Dimitrii N. Matorin; Dariusz Ficek

    2000-01-01

    Two methods of determining the chlorophyll a concentration in the sea have been formulated on the basis of artificially induced fluorescence measured with the aid of submersible fluorometers. The method of statistical correlation is founded on the empirical relationship between fluorescence and chlorophyll concentration. The theoretical model of fluorescence described in Part 1 of this paper (see Ostrowska et al. 2000, this volume) provides the basis of the other method, the physical...

  9. Gas Exchange, Chlorophyll Fluorescence and Antioxidants as Bioindicators of Airborne Heavy Metal Pollution in Jeddah, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    I.A. Hassan

    2013-08-01

    Full Text Available Lettuce (Lactuca sativa L. cv. Romaine plants were exposed to different levels of urbanization in Jeddah city, Saudi Arabia. They showed different degrees of visible injury symptoms and dramatic changes in enzymatic activities as well as net photosynthetic rates (PN, variable to maximum chlorophyll fluorescence (Fv/Fm and stomatal conductance (gs.Visual symptoms of phytotoxicity of heavy metals were observed on plants grown at industrial and urban areas, where the concentrations of metals was about 36 times higher than in other sites. The decrease in chlorophyll reached 70 and 64% in plants cultivated in the industrial and urban regions, while lengths of shoots reduced by 50 and 41% in plants collected from the same locations, respectively. The reduction in chlorophyll and other physiological and biochemical parameters were correlated with the concentrations of airborne pollutants measured in the atmosphere of the locations examined. Moreover, lettuce plants cultivated in the industrial region accumulated more heavy metals than others, which can pass into the human food chain.Photosynthetic efficiency was significantly decreased and lipid peroxidation was enhanced. Antioxidant enzymes were significantly altered during exposure.The biochemical and physiological parameters measured in the present study clearly showed that they could form the basis of a plant biomarkers battery for monitoring and predicting early effects of exposure to airborne heavy metals.

  10. NETS FOR PEACH PROTECTED CULTIVATION

    Directory of Open Access Journals (Sweden)

    Evelia Schettini

    2012-06-01

    Full Text Available The aim of this paper was to investigate the radiometric properties of coloured nets used to protect a peach cultivation. The modifications of the solar spectral distribution, mainly in the R and FR wavelength band, influence plant photomorphogenesis by means of the phytochrome and cryptochrome. The phytochrome response is characterized in terms of radiation rate in the red wavelengths (R, 600-700 nm to that in the farred radiation (FR, 700-800 nm, i.e. the R/FR ratio. The effects of the blue radiation (B, 400-500 nm is investigated by the ratio between the blue radiation and the far-red radiation, i.e. the B/FR ratio. A BLUE net, a RED net, a YELLOW net, a PEARL net, a GREY net and a NEUTRAL net were tested in Bari (Italy, latitude 41° 05’ N. Peach trees were located in pots inside the greenhouses and in open field. The growth of the trees cultivated in open field was lower in comparison to the growth of the trees grown under the nets. The RED, PEARL, YELLOW and GREY nets increased the growth of the trees more than the other nets. The nets positively influenced the fruit characteristics, such as fruit weight and flesh firmness.

  11. Chlorophylls and carotenoids of kiwifruit puree are affected similarly or less by microwave than by conventional heat processing and storage.

    Science.gov (United States)

    Benlloch-Tinoco, María; Kaulmann, Anouk; Corte-Real, Joana; Rodrigo, Dolores; Martínez-Navarrete, Nuria; Bohn, Torsten

    2015-11-15

    The impact of microwave (1000 W - 340 s) and conventional heat (97 °C - 30s) pasteurisation and storage (4, 10, 22 °C for up to 63 d) on total and individual carotenoids and chlorophylls in kiwifruit puree was evaluated. Bioaccessibility of carotenoids, before and after pasteurisation and storage, was also studied. Microwaves and conventional heating led to marked changes in the chlorophyll (42-100% losses) and carotenoid (62-91% losses) content. First- and second-order kinetics appropriately explained the degradation of total carotenoids and chlorophylls over time, respectively. Pasteurised samples showed significantly (p < 0.05) enhanced stability of these pigments, with microwaves (k = 0.007-0.031100 g mg(-1) day(-1) at 4-22 °C) promoting chlorophyll stability to a greater extent than conventional heating (k = 0.0015-0.034100 g mg(-1) day(-1) at 4-22 °C). Bioaccessibility of carotenoids remained (p < 0.05) unaffected by processing and storage. These results highlighted that the pigment composition of microwaved kiwifruit was more similar to that of the fresh fruit and better preserved during storage. PMID:25977024

  12. Dot Immunobinding Assay Method with Chlorophyll Removal for the Detection of Southern Rice Black-Streaked Dwarf Virus

    Directory of Open Access Journals (Sweden)

    Linhong Jin

    2012-06-01

    Full Text Available Southern rice black-streaked dwarf virus (SRBSDV, a new virus from Fiji, has seriously damaged rice crops in southern China and northern Vietnam in recent years. This virus is difficult to diagnose in the early stages of infection, and is very destructive at the late stage. In the present study, a dot immunobinding assay (DIBA that has a high sensitivity for diagnosing SRBSDV was developed. Two kinds of treatment for the DIBA were evaluated to determine the most effective one for removing chlorophyll interferences via rice extraction. The first included several reagents to remove chlorophyll, namely, the alkaline reagents like magnesium oxide and alumina oxide, the adsorbent reagents like activated carbon and bentonite, as well as the extraction agent acetone. The second and third treatments, which were used to remove chlorophyll in blot membrane-nitrocellulose and polyvinylidene fluoride (PVDF, included several organic solvents containing methanol, ethanol, acetone, ethyl acetate, and diethyl ether. The results showed that activated carbon and methanol yielded the best contrasting purple color for the infected samples by decreasing the chlorophyll content.

  13. Investigating chlorophyll and nitrogen levels of mangroves at Al-Khor, Qatar: an integrated chemical analysis and remote sensing approach.

    Science.gov (United States)

    Al-Naimi, Noora; Al-Ghouti, Mohammad A; Balakrishnan, Perumal

    2016-05-01

    Mangroves are unique ecosystems that dominate tropical and subtropical coastlines around the world. They provide shelter and nursery to wide variety of species such as fish and birds. Around 73 species of mangroves were recognized around the world. In Qatar, there is only one mangrove species Avicennia marina that is predominant along the northeastern coast. Assessing the health of these valuable ecosystems is vital for protection, management, and conservation of those resources. In this study, an integrated approach of chemical and remote sensing analysis was implemented to investigate the current status of the mangrove trees in Al-Khor, Qatar. Fifteen different A. marina trees from different locations in the mangrove forest were examined for their chlorophyll and nitrogen content levels. Soil analysis was also conducted to understand the effect of moisture on nitrogen availability. Results shows that currently, mangroves are in a good status in terms of nitrogen availability and chlorophyll levels which are related and both are key factors for photosynthesis. Remote sensing techniques were used for chlorophyll prediction. The results showed that these methods have the potential to be used for chlorophyll prediction and estimation. PMID:27048493

  14. HPLC Analysis of Chlorophyll a, Chlorophyll b, and Beta-Carotene in Collard Greens: A Project for a Problem-Oriented Laboratory Course.

    Science.gov (United States)

    Silveira, Augustine, Jr.; And Others

    1984-01-01

    High performance liquid chromatography (HPLC) is used to separate and quantitate beta-carotene, chlorophyll a, and chlorophyll b originating from collard greens. Experimental procedures used and typical results obtained are discussed. (JN)

  15. Hamowanie syntezy chlorofilu i RNA w izolowanych liścieniach ogórka przez N-hydroksymocznik [Inhibition of chlorophyll and RNA synthesis by N-hydroxyurea in detached cucumber cotyledons

    Directory of Open Access Journals (Sweden)

    A. Rennert

    2015-05-01

    Full Text Available N-hydroxyurea (HU at the concentration of 5 x 10-4 M decreased the content of chlorophyll in detached cucumber cotyledons; at this concentration it has no inhibitory effect on growth. Benzylaminopurine, gibberelic acid and KCl partially reversed the inhibitory effect of HU on chlorophyll synthesis. HU stimulated yellowing of barley first leaf sections. The compound had little effect on leucine-14C incorporation to protein, and markedly inhibited uracil-14C incorporation in to RNA of the greening cucumber cotyledons. It is suggested that the inhibition of RNA and chlorophyll synthesis in HU-treated cucumber cotyledons follows the HU-dependent inhibition of DNA replication.

  16. First wall for NET

    International Nuclear Information System (INIS)

    In collaboration with ANSALDO and within the frame of the European Fusion Tecnology Task N1 (Plasma Facing Components Design Studies), ENEA has performed a design an manufacturing feasibility study for the first wall of the Next European Torus (NET) during its ''physics'' operation phase. The main design specifications are average neutron wall load=1 MW/m2, peak surface heat flux=0.4 MW/m2, total number of burn pulses=1*104, average burn pulse duration=100 s, average neutron fluence=0.03 MWy/m2, structure material=AISI 316L SA, coolant=H2O at 50/100 centigrates (in/out). The reference ENEA-ANSALDO design is based on the use of flat plates coupled by microbrazing to poloidal cooling tubes. The technological development work has led to the design and manufacturing of a representative NET first wall box segment (0.65x 0.25x0.15 m) mockup which will be tested in the 190 kW Thermal Fatique Test Facility at JRC-Ispra. In this paper, we report on the various aspects of the basic experimental and theoretical investigations on the plasma-wall interactions for adequate protection of the first wall against erosion, global stress analysis of the first wall box, thecnological tests on brazed joints, and disign and manufacturing of the first wall mockup

  17. Analysis of Chloroplast Ultrastructure, Photosystem Ⅱ Light Harvesting Complexes and Chlorophyll Synthesis in a Chlorophyll-Less Rice Mutant W2555

    Institute of Scientific and Technical Information of China (English)

    XU Pei-zhou; LI Yun; YUAN Shu; ZHANG Hong-yu; WANG Xu-dong; LIN Hong-hui; WU Xian-jun

    2006-01-01

    A comparative study on chloroplast ultrastructure and light harvesting complex of photosystem Ⅱ (LHC Ⅱ) was conducted between a new rice mutant (W2555) and its wild type (WT). The chloroplasts of W2555 had less thylakoids and grana stacks compared with the wild type. There was no significant change in the composition of LHC Ⅱ polypeptide in W2555, while a decline had been noted in LHC Ⅱ content. Northern blot analysis with a specific cab gene probe showed no appreciable difference in the LHC Ⅱ mRNA level between the W2555 and its wild type. The precursors of chlorophyll synthesis, δ-aminolevulinic acid (ALA)and porphobilinogen (PBG) were over accumulated in W2555, but the other precursors were all decreased. These results indicated that the decreased level of LHC Ⅱ in the mutant W2555 was attributed to the change of cab gene transcription, but a blockage in chlorophyll biosynthesis due to the formation of uroporphyrinogen Ⅲ (Urogen Ⅲ).

  18. The Construction of the Spatial-Temporal Contents Integrated System Basing on NetGIS%基于网络GIS技术的时空典藏整合环境构建

    Institute of Scientific and Technical Information of China (English)

    农晓珍

    2015-01-01

    Spatial-Temporal information that is all the content data are available in the basic characteristics , through the spatial and temporal information processing technology construction of time -space coordinate system , let all the digital archives of the content can be integrated, through an open network exchange mechanism , let originally stored information in different institutions can distributed storage, and can refer to each other is sheathed , contributed to the integration of information .This paper explores the use of internet geographic information system construction of Digital Archives Program spatial -temporal intension infrastructure .Its main objective is expanding existing geographic information system connotation , development into temporal and spatial information processing technolo-gy, constructs the spatial-temporal intension infrastructure , with precise temporal and spatial reference system as the basis , the es-tablishment of the connotation of all collection time and geographical space markers ( geographic footprint ) , mainly on the basis of in-formation retrieval and information integration , and provide more vivid , readable , and precision of the events of the original ( Spatial Visualization) in visual space .%时空信息是所有内涵数据都具备的基本特性,通过时空信息处理技术建构时空坐标体系,让所有数字典藏的内容得以整合,通过网络开放式交换机制,让原本储存在不同机构的信息,既可以分散储存,又可以彼此引用套合,促成信息统整。本文探讨了利用互联网地理信息系统建构数字典藏计划的时空内涵基础架构,其最主要目的在于扩充原有地理信息系统内涵,发展成时间及空间信息处理技术,建构起时空内涵基础架构,以精确的时空参考系统为基础,建立所有典藏内涵的时间与地理空间标记( geographic footprint ),做为信息检索和信息整合的主要依

  19. [Pigment accumulation and functional activity of chloroplasts in common Pisum sativum L. mutants with low chlorophyll level (chlorotica)].

    Science.gov (United States)

    Ladygin, V G

    2003-01-01

    Pea mutants chlorotica 2004 and 2014 with a low content of chlorophyll were studied. The mutant 2004 has light green leaves and stem, and the mutant 2014 has yellow green leaves and stem. They accumulate approximately 80 and 50% chlorophylls of the parent form of pea Torsdag cv. The content of carotene in carotenoids of the mutant 2004 was much lower, and the accumulation of lutein and violaxanthine was increased. The accumulation of all carotenoids in the mutant 2014 decreased almost proportionally to a decrease in the chlorophyll content. The rate of CO2 evolution in mutant chlorotica 2004 and 2014 was established to be lower. The quantum efficiency of photosynthesis in the mutants was 29-30% lower as compared to the control, and in hybrid plants it was 1.5-2-fold higher. It is assumed that the increase in the activity of the night-time respiration in gas exchange of chlorotica mutants and the drop of photosynthesis lead to a decrease in biomass increment. The results obtained allow us to conclude that the mutation of chlorotica 2004 and 2014 affects the genes controlling the formation and functioning of different components of the photosynthetic apparatus. PMID:12723346

  20. Dumbing Down the Net

    Science.gov (United States)

    Jamison, Mark A.; Hauge, Janice A.

    It is commonplace for sellers of goods and services to enhance the value of their products by paying extra for premium delivery service. For example, package delivery services such as Federal Express and the US Postal Service offer shippers a variety of delivery speeds and insurance programs. Web content providers such as Yahoo! and MSN Live Earth can purchase web-enhancing services from companies such as Akamai to speed the delivery of their web content to customers.1

  1. Professional ASP.NET 4 in C# and VB

    CERN Document Server

    Evjen, Bill; Rader, Devin

    2010-01-01

    This book was written to introduce you to the features and capabilities that ASP.NET 4 offers, as well as to give you an explanation of the foundation that ASP.NET provides. We assume you have a general understanding of Web technologies, such as previous versions of ASP.NET, Active Server Pages 2.0/3.0, or JavaServer Pages. If you understand the basics of Web programming, you should not have much trouble following along with this book's content. If you are brand new to ASP.NET, be sure to check out Beginning ASP.NET 4: In C# and VB by Imar Spaanjaars (Wiley Publishing, Inc., 2010) to help you

  2. Net Neutrality and Internet Fragmentation: The Role of Online Advertising

    OpenAIRE

    D'Annunzio, Anna; Russo, Antonio

    2015-01-01

    We investigate the relation between Net Neutrality regulation and Internet fragmentation. We model a two-sided market, where Content Providers (CPs) and consumers interact through Internet Service Providers (ISPs), and CPs sell consumers' attention to advertisers. Under Net Neutrality, a zero-price rule is enforced. In the Unregulated Regime, instead, ISPs make access to their subscribers conditional on payment of a termination fee. Multiple impressions of an ad on the same consumer are parti...

  3. Hamowanie syntezy chlorofilu i RNA w izolowanych liścieniach ogórka przez N-hydroksymocznik [Inhibition of chlorophyll and RNA synthesis by N-hydroxyurea in detached cucumber cotyledons

    OpenAIRE

    A. Rennert; J. S. Knypl

    2015-01-01

    N-hydroxyurea (HU) at the concentration of 5 x 10-4 M decreased the content of chlorophyll in detached cucumber cotyledons; at this concentration it has no inhibitory effect on growth. Benzylaminopurine, gibberelic acid and KCl partially reversed the inhibitory effect of HU on chlorophyll synthesis. HU stimulated yellowing of barley first leaf sections. The compound had little effect on leucine-14C incorporation to protein, and markedly inhibited uracil-14C incorporation in to RNA of the gree...

  4. Chlorophyll biosynthesis and assembly into chlorophyll-protein complexes in isolated developing chloroplasts

    International Nuclear Information System (INIS)

    Isolated developing plastids from greening cucumber cotyledons or from photoperiodically grown pea seedlings incorporated 14C-labeled 5-aminolevulinic acid (ALA) into chlorophyll (Chl). Incorporation was light dependent, enhanced by S-adenosylmethionine, and linear for 1 hr. The in vitro rate of Chl synthesis from ALA was comparable to the in vivo rate of Chl accumulation. Levulinic acid and dioxoheptanoic acid strongly inhibited Chl synthesis but not plastid protein synthesis. Neither chloramphenicol nor spectinomycin affected Chl synthesis, although protein synthesis was strongly inhibited. Components of thylakoid membranes from plastids incubated with [14C]ALA were resolved by electrophoresis and then subjected to autoradiography. This work showed that (i) newly synthesized Chl was assembled into Chl-protein complexes and (ii) the inhibition of protein synthesis during the incubation did not alter the labeling pattern. Thus, there was no observable short-term coregulation between Chl synthesis (from ALA) and the synthesis of membrane proteins in isolated plastids

  5. Identification of a peroxisomal-targeted aldolase involved in chlorophyll biosynthesis and sugar metabolism in rice.

    Science.gov (United States)

    Zhang, Fei; Zhang, Pan; Zhang, Yu; Wang, Shouchuang; Qu, Lianghuan; Liu, Xianqing; Luo, Jie

    2016-09-01

    Chlorophyll plays remarkable and critical roles in photosynthetic light-harvesting, energy transduction and plant development. In this study, we identified a rice Chl-deficient mutant, ygdl-1 (yellow green and droopy leaf-1), which showed yellow-green leaves throughout plant development with decreased content of Chls and carotene and an increased Chl a/b ratio. The ygdl-1 mutant also exhibited severe defects in chloroplast development, including disorganized grana stacks. Sequence analysis revealed that the mutant contained a T-DNA insertion within the promoter of a fructose-1,6-bisphosphate aldolase (OsAld-Y), which dramatically reduced the OsAld-Y mRNA level, and its identity was verified by transgenic complementation. Real-time PCR analysis showed that the expression levels of genes associated with chlorophyll biosynthesis and chloroplast development were concurrently altered in the ygdl-1 mutant. The expression of OsAld-Y-GFP fusion protein in tobacco epidermal cells showed that OsAld-Y was localized to the peroxisome. In addition, the analysis of primary carbon metabolites revealed the significantly reduced levels of sucrose and fructose in the mutant leaves, while the glucose content was similar to wild-type plants. Our results suggest that the OsAld-Y participates in Chl accumulation, chloroplast development and plant growth by influencing the photosynthetic rate of leaves and the sugar metabolism of rice. PMID:27457997

  6. Effect of Zn stresses on physiology, growth, Zn accumulation, and chlorophyll of Phyllostachys pubescen s.

    Science.gov (United States)

    Peng, Danli; Shafi, Mohammad; Wang, Ying; Li, Song; Yan, Wenbo; Chen, Junren; Ye, Zhengqian; Liu, Dan

    2015-10-01

    The effects of Zinc (Zn) on lipid peroxidation, antioxidative enzymes, growth, Zn accumulation, and leaf chlorophyll of Phyllostachys pubescens (Pradelle) Mazel ex J.Houz. were investigated in two greenhouse experiments. Hydroponics experiment with Zn application of 0, 20, 100, and 400 μM revealed that lower concentration of Zn in solution led to increased malondialdehyde (MDA) and proline contents but inhibited SOD activity in all treatments. P. pubescens had showed strong ability to accumulate Zn in stems and reached maximum level at 100 μM with 7.91-fold increase compared with control. In pot experiment, treatment with Zn ranged from 0, 200, 400, 800, 1,600, to 3,200 mg kg(-1). Application of 800 mg kg(-1) revealed 116, 24.6, and 28.3 times increase in Zn concentration of roots, stems, and leaves, respectively. Growth and chlorophyll contents of plants in pots were better promoted at 400 mg kg(-1) Zn, with 60.5 and 30.9 % enhanced roots and shoot compared with control. The bioaccumulation factor (BAF) was in the sequence of stem > roots > leaves. The translocation factor (TF) of stem was higher than leaves. PMID:26002363

  7. Instrumentation in Developing Chlorophyll Fluorescence Biosensing: A Review

    Directory of Open Access Journals (Sweden)

    Jesus R. Millan-Almaraz

    2012-08-01

    Full Text Available Chlorophyll fluorescence can be defined as the red and far-red light emitted by photosynthetic tissue when it is excited by a light source. This is an important phenomenon which permits investigators to obtain important information about the state of health of a photosynthetic sample. This article reviews the current state of the art knowledge regarding the design of new chlorophyll fluorescence sensing systems, providing appropriate information about processes, instrumentation and electronic devices. These types of systems and applications can be created to determine both comfort conditions and current problems within a given subject. The procedure to measure chlorophyll fluorescence is commonly split into two main parts; the first involves chlorophyll excitation, for which there are passive or active methods. The second part of the procedure is to closely measure the chlorophyll fluorescence response with specialized instrumentation systems. Such systems utilize several methods, each with different characteristics regarding to cost, resolution, ease of processing or portability. These methods for the most part include cameras, photodiodes and satellite images.

  8. An overview of remote sensing of chlorophyll fluorescence

    Science.gov (United States)

    Xing, Xiao-Gang; Zhao, Dong-Zhi; Liu, Yu-Guang; Yang, Jian-Hong; Xiu, Peng; Wang, Lin

    2007-03-01

    Besides empirical algorithms with the blue-green ratio, the algorithms based on fluorescence are also important and valid methods for retrieving chlorophyll-a concentration in the ocean waters, especially for Case II waters and the sea with algal blooming. This study reviews the history of initial cognitions, investigations and detailed approaches towards chlorophyll fluorescence, and then introduces the biological mechanism of fluorescence remote sensing and main spectral characteristics such as the positive correlation between fluorescence and chlorophyll concentration, the red shift phenomena. Meanwhile, there exist many influence factors that increase complexity of fluorescence remote sensing, such as fluorescence quantum yield, physiological status of various algae, substances with related optical property in the ocean, atmospheric absorption etc. Based on these cognitions, scientists have found two ways to calculate the amount of fluorescence detected by ocean color sensors: fluorescence line height and reflectance ratio. These two ways are currently the foundation for retrieval of chlorophyl l - a concentration in the ocean. As the in-situ measurements and synchronous satellite data are continuously being accumulated, the fluorescence remote sensing of chlorophyll-a concentration in Case II waters should be recognized more thoroughly and new algorithms could be expected.

  9. High-level Petri Nets

    DEFF Research Database (Denmark)

    of low-level Petri nets - while, on the other hand, they still offer a wide range of analysis methods and tools. The step from low-level nets to high-level nets can be compared to the step from assembly languages to modern programming languages with an elaborated type concept. In low-level nets...... the book as useful as possible, the selected papers represent the current "state of the art" of high-level nets. This means that we have been forced to leave out a number of older papers which have had a profound influence on the development of high-level Petri nets - but by now have been superseded...

  10. Sombreamento de plantas de Catharanthus roseus (L. G. Don 'Pacifica White' por malhas coloridas: desenvolvimento vegetativo Shading of 'Pacifica White' Catharanthus roseus (L. G. Don plants with colored nets: vegetative development

    Directory of Open Access Journals (Sweden)

    Anderson Adriano Martins Melo

    2009-04-01

    Full Text Available As malhas coloridas têm sido utilizadas para manipular o desenvolvimento vegetativo, melhorando a utilização da radiação solar por plantas ornamentais. Objetivou-se, neste trabalho estudar o efeito da redução de 50% da radiação fotossinteticamente ativa sobre o crescimento vegetativo de plantas de Catharanthus roseus (L. G. Don, por meio de malhas azul e vermelha e malha preta, em comparação com plantas crescidas na ausência de sombreamento (pleno sol. As plantas foram obtidas a partir de sementes e tratadas por 180 dias. Foram avaliados o ganho de biomassa e a distribuição de matéria seca nas plantas, o conteúdo de pigmentos foliares (clorofilas e carotenóides e de nitrogênio foliar. A malha vermelha provocou um aumento de matéria seca total e de área foliar das plantas em comparação com as malhas azul, preta e ao tratamento a pleno sol, porém, exceto em relação a esse tratamento, a malha vermelha causou menor conteúdo de nitrogênio e pigmentos foliares. A maior relação raiz/parte aérea e relação clorofila a/b, menores razões de área foliar e de massa foliar das plantas crescidas a pleno sol em relação às plantas sombreadas indicam um efeito mais proeminente da irradiância mais alta do que da alteração do espectro de luz. O sombreamento altera significativamente a distribuição de matéria seca e o uso de malhas de diferentes cores modifica o conteúdo de pigmentos fotossintéticos dessa espécie.Colored shade nets have been used to manipulate the vegetative development, improving the utilization of solar radiation by ornamental plants. This work aimed to study the effect of 50% reduction of PAR on vegetative growth of plants of Catharanthus roseus (L. G. Don, using blue and red nets, and black net, in comparison to plants growing under full sunlight (lack of shading. The plants were obtained from seeds and treated for 180 days. Biomass increment and distribution, pigment content (chlorophylls and

  11. Initial CAD investigations for NET

    International Nuclear Information System (INIS)

    This report summarizes the work done under contract no. 164/84-7/FU-D-/NET between the Commission of the European Communities and KfK during the period from June 1, 1984, through May 31, 1985. The following topics are covered in this report: Initial modelling of NET version NET2A, CAD system extension for remote handling studies, analysis of the CAD information structure, work related to the transfer of CAD information between KfK and the NET team. (orig.)

  12. Using SPAD-502 to evaluate the total chlorophyll and nitrogen status in leaves of longkong (Aglaia dookkoo Griff.) and rambutan (Nephelium lappaseum L.)

    OpenAIRE

    Chanaweerawan, S.; Sdoodee, S.

    2002-01-01

    Total chlorophyll and nitrogen status in leaves of longkong and rambutan were evaluated by using the SPAD-502 meter. Leaves of both species were sampled from 10 year-old trees grown in an experimental plot at Prince of Songkla University, Hat Yai campus. The relationship between SPAD-502 meter reading (SPAD) and total chlorophyll content analyzed in the laboratory was evaluated in longkong and rambutan, and they were y = -2.68+0.21x, r2 = 0.77** and y = -1.11+0.18x, r2 = 0.77**, respectively....

  13. Modeling of estuarne chlorophyll a from an airborne scanner

    Science.gov (United States)

    Khorram, Siamak; Catts, Glenn P.; Cloern, James E.; Knight, Allen W.

    1987-01-01

    Near simultaneous collection of 34 surface water samples and airborne multispectral scanner data provided input for regression models developed to predict surface concentrations of estuarine chlorophyll a. Two wavelength ratios were employed in model development. The ratios werechosen to capitalize on the spectral characteristics of chlorophyll a, while minimizing atmospheric influences. Models were then applied to data previously acquired over the study area thre years earlier. Results are in the form of color-coded displays of predicted chlorophyll a concentrations and comparisons of the agreement among measured surface samples and predictions basedon coincident remotely sensed data. The influence of large variations in fresh-water inflow to the estuary are clearly apparent in the results. The synoptic view provided by remote sensing is another method of examining important estuarine dynamics difficult to observe from in situ sampling alone.

  14. Interacting effects of elevated temperature and additional water on plant physiology and net ecosystem carbon fluxes in a high Arctic ecosystem

    Science.gov (United States)

    Maseyk, Kadmiel; Seibt, Ulrike; Lett, Céline; Lupascu, Massimo; Czimczik, Claudia; Sullivan, Patrick; Welker, Jeff

    2013-04-01

    Arctic ecosystems are experiencing temperature increases more strongly than the global average, and increases in precipitation are also expected amongst the climate impacts on this region in the future. These changes are expected to strongly influence plant physiology and soil biogeochemistry with subsequent implications for system carbon balance. We have investigated the effects of a long-term (10 years) increase in temperature, soil water and the combination of both on a tundra ecosystem at a field manipulation experiment in NW Greenland. Leaf gas exchange, chlorophyll fluorescence, carbon (C) and nitrogen (N) content and leaf isotopic composition, and leaf morphology were measured on Salix arctica plants in treatment and control plots in June-July 2011, and continuous measurements of net plant and soil fluxes of CO2 and water were made using automatic chambers coupled to a trace gas laser analyzer. Plants in the elevated temperature (T2) treatment had the highest photosynthetic capacity in terms of net CO2 assimilation rates and photosystem II efficiencies, and lowest rates of non-photochemical energy dissipation during photosynthesis. T2 plants also had the highest leaf N content, specific leaf area (SLA) and saturation light level of photosynthesis. It appears that warming increases soil N availability, which the plants direct towards increasing photosynthetic capacity and producing larger thinner leaves. On the other hand, the plants in the plots with both elevated temperatures and additional water (T2W) had the lowest photosystem II efficiencies and the highest rates of non-photochemical energy dissipation, due more to higher levels of constitutive energy dissipation than regulated thermal quenching. Watering, both in combination with higher temperatures and alone (W treatment), also reduced leaf SLA and leaf N relative to control plots. However, net photosynthetic rates remained similar to control plants, due in part to higher stomatal conductance (W) and

  15. Investigating the Control of Chlorophyll Degradation by Genomic Correlation Mining.

    Science.gov (United States)

    Ghandchi, Frederick P; Caetano-Anolles, Gustavo; Clough, Steven J; Ort, Donald R

    2016-01-01

    Chlorophyll degradation is an intricate process that is critical in a variety of plant tissues at different times during the plant life cycle. Many of the photoactive chlorophyll degradation intermediates are exceptionally cytotoxic necessitating that the pathway be carefully coordinated and regulated. The primary regulatory step in the chlorophyll degradation pathway involves the enzyme pheophorbide a oxygenase (PAO), which oxidizes the chlorophyll intermediate pheophorbide a, that is eventually converted to non-fluorescent chlorophyll catabolites. There is evidence that PAO is differentially regulated across different environmental and developmental conditions with both transcriptional and post-transcriptional components, but the involved regulatory elements are uncertain or unknown. We hypothesized that transcription factors modulate PAO expression across different environmental conditions, such as cold and drought, as well as during developmental transitions to leaf senescence and maturation of green seeds. To test these hypotheses, several sets of Arabidopsis genomic and bioinformatic experiments were investigated and re-analyzed using computational approaches. PAO expression was compared across varied environmental conditions in the three separate datasets using regression modeling and correlation mining to identify gene elements co-expressed with PAO. Their functions were investigated as candidate upstream transcription factors or other regulatory elements that may regulate PAO expression. PAO transcript expression was found to be significantly up-regulated in warm conditions, during leaf senescence, and in drought conditions, and in all three conditions significantly positively correlated with expression of transcription factor Arabidopsis thaliana activating factor 1 (ATAF1), suggesting that ATAF1 is triggered in the plant response to these processes or abiotic stresses and in result up-regulates PAO expression. The proposed regulatory network includes the

  16. Ecology: a niche for cyanobacteria containing chlorophyll d

    DEFF Research Database (Denmark)

    Kühl, Michael; Chen, Min; Ralph, Peter J;

    2005-01-01

    The cyanobacterium known as Acaryochloris marina is a unique phototroph that uses chlorophyll d as its principal light-harvesting pigment instead of chlorophyll a, the form commonly found in plants, algae and other cyanobacteria; this means that it depends on far-red light for photosynthesis. Here...... we demonstrate photosynthetic activity in Acaryochloris-like phototrophs that live underneath minute coral-reef invertebrates (didemnid ascidians) in a shaded niche enriched in near-infrared light. This discovery clarifies how these cyanobacteria are able to thrive as free-living organisms...

  17. Endolithic chlorophyll d-containing phototrophs

    DEFF Research Database (Denmark)

    Behrendt, Lars; Larkum, Anthony W D; Norman, Anders;

    2011-01-01

    Cyanobacteria in the genus Acaryochloris are the only known oxyphototrophs that have exchanged chlorophyll a (Chl a) with Chl d as their primary photopigment, facilitating oxygenic photosynthesis with near infrared (NIR) light. Yet their ecology and natural habitats are largely unknown. We used...... hyperspectral and variable chlorophyll fluorescence imaging, scanning electron microscopy, photopigment analysis and DNA sequencing to show that Acaryochloris-like cyanobacteria thrive underneath crustose coralline algae in a widespread endolithic habitat on coral reefs. This finding suggests an important role...... of Chl d-containing cyanobacteria in a range of hitherto unexplored endolithic habitats, where NIR light-driven oxygenic photosynthesis may be significant....

  18. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto;

    . Chlorophyll a fluorescence has been a versatile tool in photosynthesis research to measure plant responses to various abiotic stresses that affect PSII. We aim to establish a reproducible protocol to measure response of wheat genotypes to high temperature, based on the physiological marker, maximum quantum......%. Our protocol seems to be stable over environments since interaction between genotypes and the three repeated experiments separated in time was not statistically significant. The chlorophyll a fluorescence protocol may enable identification of wheat lines reliably more or less tolerant to heat stress...

  19. Rare, but challenging tumors: NET

    International Nuclear Information System (INIS)

    Full text: Introduction: Gastroenteropancreatic Neuroendocrine Tumors (GEP - NET) are a heterogeneous group of tumors with different locations and many different clinical, histological, and imaging performance. In a part of them a secretion of various organic substances is present. The morbidity of GEP - NET in the EU is growing, and this leads to increase the attention to them. What you will learn: Imaging methods used for localization and staging of GEP - NET, characteristics of the study’s protocols; Classification of GEP - NET; Demonstration of typical and atypical imaging features of GEP - NET in patients registered at the NET Center at University Hospital ‘St. Marina’, Varna; Features of metastatic NET, The role of imaging in the evaluation of treatment response and follow-up of the patients. Discussion: The image semiotics analysis is based on 19 cases of GEP - NET registered NET Center at University Hospital ‘St. Marina’. The main imaging method is multidetector CT (MDCT), and magnetic resonance imaging (MRI ) has advantages in the evaluation of liver lesions and the local prevalence of anorectal tumors. In patients with advanced disease and liver lesions the assessment of skeletal involvement (MRI/ nuclear medical method) is mandatory. The majority of GEP - NET have not any specific imaging findings. Therefore it is extremely important proper planning and conducting of the study (MDCT and MR enterography; accurate assessment phase of scanning, positive and negative contrast). Conclusion: GEP - NET is a major diagnostic challenge due to the absence of typical imaging characteristics and often an overlap with those of the tumors of different origin can be observed. Therefore, a good knowledge of clinical and imaging changes occurring at different locations is needed. MDCT is the basis for the diagnosis, staging and follow-up of these neoplasms

  20. 康奈尔净碳水化合物-蛋白质体系预测小肠可消化粗蛋白质含量%Predicting Utilizable Crude Protein Content in Small Intestine by Cornell Net Carbohydrate and Protein System

    Institute of Scientific and Technical Information of China (English)

    王燕; 杨方; 陈常栋; 王海威; 张微微; 张永根

    2012-01-01

    This study was conducted to establish mathematical models of predicting utilizable crude protein (uCP) content in feed for dairy cows using Cornell net carbohydrate and protein system (CNCPS). Contents of protein fractions of 13 kinds of common feeds were analyzed using CNCPS, and uCP of feeds was determined using mobile nylon bag method, and three Holstein dairy cows with permanent ruminal and duodenal cannulas were used in a single factor experimental design. The results showed as follows: 1) contents of uCP in soybean meal, cottonseed meal, rapeseed meal, sunflower seed meal, sesame meal, corn germ meal, rice bran, rice bran cake, rice bran meal, barley, wheat bran, corn and corn gluten feed were 390. 32, 321. 90, 297.21, 230.50, 388.62, 177.49, 85.53, 116.78, 134.74, 80.47, 128.26, 70.28 and 66. 65 g/kg, respectively. 2) The regression equation of contents of measured uCP and CNCPS fractions in all experimental feeds was uCP = -4.11 + 6.48PA+7.73PB, + 5.72PB2 +8.26PB3 +5. UPC (R2 =0.997 2, P<0.01) ; the regression equation of contents of measured uCP and CNCPS fractions in protein feed was uCP =12. 79 + 5. 47PA +7. 04PBl +9. 74PB2 +8. 14PB3 (R2 = 0. 998 7, P < 0. 01) ; the regression equation of contents of measured uCP and CNCPS fractions in energy feed was uCP = 14. 80 +8. 55PA +6. 27PB2 +17. 64PB3(R2 = 0.987 4, P<0.01). 3) Regression coefficients (R2) between CNCPS fractions contents and measured uCP contents in protein feed, energy feed and all experimental feed were all higher than 0. 95, and regression coefficient between measured uCP content and CNCPS fractions contents in protein feed was higher than that in energy feed. In conclusion, it is feasible that using contents of protein components subdivided by CNCPS to predict uCP content, and the prediction result in protein feed is more accurate than that in energy feed.%本试验旨在建立奶牛饲料的康奈尔净碳水化合物-蛋白质体系(Cornell net carbohydrate and protein system,CNCPS)预测

  1. DMAH ozone measurement net

    Directory of Open Access Journals (Sweden)

    D. Pagès

    2006-01-01

    Full Text Available The complexity of the study of tropospheric ozone lies in the fact that it is a secondary pollutant. It is not emitted by a source, instead its concentration in the air depends on other compounds (especially the nitrogen oxides emitted by motor vehicles and the volatile organic compounds emitted by the industry and the vegetation and meteorological factors (especially solar radiation and temperature. The European legislation compells to make measurements of the tropospheric ozone due to its effects on people (fatigue, irritation of the mucous membranes, aggravation of asthma ... and on environment (decrease of the production of cereals, synergy with plagues .... The measuring net in Catalonia belongs to the Department of Environment and Housing (DMAH. It has a pyramidal structure and it allows a surveillance to notify in case of exceeding a certain threshold. From the registered data of last years it is shown that the number of incidences is related to meteorology. They are more frequent during afternoon and the behaviour of this pollutant is different according to the proximity of the point of measurement to the sources of its precursors.

  2. Chlorophyll Fluorescence as a Tool to Assess the Regeneration Potential of African Violet Leaf Explants

    Directory of Open Access Journals (Sweden)

    Norbert KEUTGEN

    2016-06-01

    Full Text Available Micropropagation of many ornamentals has enabled their efficient commercialisation and many problems have been solved by the elaboration of adequate culture protocols. Nevertheless, a non-destructive technique for monitoring the developmental progress of explants would be desirable. The present study focussed on the applicability of chlorophyll fluorescence in leaf explants of African violet (a Saintpaulia ionantha × confusa – hybrid explanted onto Murashige and Skoog basic medium. The explants that survived on the medium without additional phytohormones had the capacity to develop further into two different kinds of explants: light green explants, characterized by a non-regular size growth and stiffer appearance, and dark green explants capable of organogenesis. Compared to the source leaves of African violet plants, explants were characterized by reduced chlorophyll (Chl and carotenoid (Car contents as well as a tendency towards a higher Car/Chl ratio. The Chl a/b ratio decreased significantly in the light green explants. A reduction of maximum quantum efficiency of photosystem II (Fv/Fm accompanied by a high percentage (> 50% of thermal energy dissipation as a consequence of an elevated light intensity (800 µmol m-2 s-1 quanta indicated photoinhibition in the light green explants, whereas in the dark green explants the largest percentage (> 50% of the light energy was dissipated into the fraction of photon energy trapped by ‘closed’ photosystem II reaction centres. These results suggest that the capacity of organogenesis of leaf explants of African violet can be monitored using chlorophyll fluorescence, because it is related to modifications of the photosynthetic system.

  3. Measuring chlorophyll a and 14C-labeled photosynthate in aquatic angiosperms by the use of a tissue solubilizer

    International Nuclear Information System (INIS)

    A compound that quantitatively correlated with chlorophyll a could be measured fluorometrically in the extracts of leaves of three aquatic angiosperms (Myriophyllum heterophyllum Michx., Potamogeton crispus L., Elodea canadensis Michx.) treated with the tissue solubilizer BTS-450. Fluorescent characteristics of the solubilized plant tissues were stable for several weeks in the dark at temperatures up to 600C but rapidly degraded in sunlight or when acidified. 14C-Labeled photosynthate, which had been fixed by leaf discs during 1- to 10-hour exposure to H14CO3, was also readily extracted by the tissue solubilizer. Solubilizer extraction can, therefore, be use to determine both chlorophyll a content and 14C incorporation rates in the same leaf sample. The method is practical, because no grinding is required, the fluorescent characteristics of the extracts are stable, and analyses can be performed with very little plant material

  4. Measuring chlorophyll α and 14C-labeled photosynthate in aquatic angiosperms by the use of a tissue solubilizer

    International Nuclear Information System (INIS)

    A compound that quantitatively correlated with chlorophyll α could be measured fluorometrically in the extracts of leaves of three aquatic angiosperms (Myriophyllum heterophyllum Michx., Potamogeton crispus L., Elodea canadensis Michx.) treated with the tissue solubilizer BTS-450. Fluorescent characteristics of the solubilized plant tissues were stable for several weeks in the dark at temperatures up to 600C but rapidly degraded in sunlight or when acidified. 14C-Labeled photosynthate, which had been fixed by leaf discs during 1- to 10-hour exposure to H14CO3, was also readily extracted by the tissue solubilizer. Solubilizer extraction can, therefore, be used to determine both chlorophyll α content and 14C incorporation rates in the same leaf sample. The method is practical, because no grinding is required, the fluorescent characteristics of the extracts are stable, and analyses can be performed with very little plant material (about 3 milligrams)

  5. Analysis of Cross-Seasonal Spectral Response from Kettle Holes: Application of Remote Sensing Techniques for Chlorophyll Estimation

    Directory of Open Access Journals (Sweden)

    Bernd Lennartz

    2012-11-01

    Full Text Available Kettle holes, small inland water bodies usually less than 1 ha in size, are subjected to pollution, drainage, and structural alteration by intensive land use practices. This study presents the analysis of spectral signatures from kettle holes based on in situ water sampling and reflectance measurements in application for chlorophyll estimation. Water samples and surface reflectance from kettle holes were collected from 6 ponds in 15 field campaigns (5 in 2007 and 10 in 2008, resulting in a total of 80 spectral datasets. We assessed the existing semi-empirical algorithms to determine chlorophyll content for different types of kettle holes using seasonal and cross-seasonal volume reflectance and derivative spectra. Based on this analysis and optical properties of water leaving reflectance from kettle holes, the following typology of the remote signal interpretation was proposed: Submerged vegetation, Phytoplankton dominated and Mixed type.

  6. Land cover classification in Ukrainian Carpathians using the MERIS Terrestrial Chlorophyl Index and red edge position from ENVISAT MERIS data

    Science.gov (United States)

    Lyalko, V. I.; Shportyuk, Z. M.; Sakhatskyi, O. L.; Sybirtseva, O. M.

    We present some results of a preliminary study of the possibility to use MERIS data for land cover classification in the Ukrainian Carpathians. The ENVISAT MERIS data (16 April 2004) with a rough space resolution of 1200m are used to calculate the red edge indices: the Red Edge Position (REP), MERIS Terrestrial Chlorophyll Index (MTCI) and NDVI. The classification using REP and MTCI images gives better results than with reflectance by the method of minimum distance to means (MMDM). The calculation results showed that the MERIS image with a rough space resolution provided moderate classification results: only coniferous forests and snow are well classified. MTCI is sensitive to a broad range of the chlorophyll contents and much less sensitive to topographical effect in mountain region. The investigation results show a good correlation between REP and MTCI and a high potential for monitoring for the ecosystems in mountain regions using a combination of both indices.

  7. Hierarchies in Coloured Petri Nets

    DEFF Research Database (Denmark)

    Huber, Peter; Jensen, Kurt; Shapiro, Robert M.

    1991-01-01

    The paper shows how to extend Coloured Petri Nets with a hierarchy concept. The paper proposes five different hierarchy constructs, which allow the analyst to structure large CP-nets as a set of interrelated subnets (called pages). The paper discusses the properties of the proposed hierarchy...

  8. Linear Logic on Petri Nets

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik; Winskel, Glynn

    This article shows how individual Petri nets form models of Girard's intuitionistic linear logic. It explores questions of expressiveness and completeness of linear logic with respect to this interpretation. An aim is to use Petri nets to give an understanding of linear logic and give some apprai...

  9. MICROSOFT ADO.NET OHJELMISTOTUOTANNOSSA

    OpenAIRE

    Kyllönen, Juhani

    2005-01-01

    Tämän opinnäytetyön tarkoituksena oli tutustua Microsoft .NET -ohjelmointiympäristöön sisälty-vään ADO.NET -tietokantarajapintaan käytännön tasolla. Opinnäytetyön teoriaosuus käsittelee ADO.NET:in perustan muodostavien luokkakirjastojen toimintaa. Tarkastelun kohteena ovat ylei-simpien luokkien tärkeimmät ominaisuudet ja metodit. Opinnäytetyön käytännön osassa tavoitteena oli ohjelmoida liiketoimintalogiikka Microsoft SQL -tietokantaa käyttävää ASP.NET -sovellusta varten. ADO.NET on uusin ...

  10. A Small Universal Petri Net

    Directory of Open Access Journals (Sweden)

    Dmitry A. Zaitsev

    2013-09-01

    Full Text Available A universal deterministic inhibitor Petri net with 14 places, 29 transitions and 138 arcs was constructed via simulation of Neary and Woods' weakly universal Turing machine with 2 states and 4 symbols; the total time complexity is exponential in the running time of their weak machine. To simulate the blank words of the weakly universal Turing machine, a couple of dedicated transitions insert their codes when reaching edges of the working zone. To complete a chain of a given Petri net encoding to be executed by the universal Petri net, a translation of a bi-tag system into a Turing machine was constructed. The constructed Petri net is universal in the standard sense; a weaker form of universality for Petri nets was not introduced in this work.

  11. NET remote workstation

    International Nuclear Information System (INIS)

    The goal of this NET study was to define the functionality of a remote handling workstation and its hardware and software architecture. The remote handling workstation has to fulfill two basic functions: (1) to provide the man-machine interface (MMI), that means the interface to the control system of the maintenance equipment and to the working environment (telepresence) and (2) to provide high level (task level) supporting functions (software tools) during the maintenance work and in the preparation phase. Concerning the man-machine interface, an important module of the remote handling workstation besides the standard components of man-machine interfacing is a module for graphical scene presentation supplementing viewing by TV. The technique of integrated viewing is well known from JET BOOM and TARM control using the GBsim and KISMET software. For integration of equipment dependent MMI functions the remote handling workstation provides a special software module interface. Task level support of the operator is based on (1) spatial (geometric/kinematic) models, (2) remote handling procedure models, and (3) functional models of the equipment. These models and the related simulation modules are used for planning, programming, execution monitoring, and training. The workstation provides an intelligent handbook guiding the operator through planned procedures illustrated by animated graphical sequences. For unplanned situations decision aids are available. A central point of the architectural design was to guarantee a high flexibility with respect to hardware and software. Therefore the remote handling workstation is designed as an open system based on widely accepted standards allowing the stepwise integration of the various modules starting with the basic MMI and the spatial simulation as standard components. (orig./HP)

  12. Measurement of Sun Induced Chlorophyll Fluorescence Using Hyperspectral Satellite Imagery

    Science.gov (United States)

    Irteza, S. M.; Nichol, J. E.

    2016-06-01

    Solar Induced Chlorophyll Fluorescence (SIF), can be used as an indicator of stress in vegetation. Several scientific approaches have been made and there is considerable evidence that steady state Chlorophyll fluorescence is an accurate indicator of plant stress hence a reliable tool to monitor vegetation health status. Retrieval of Chlorophyll fluorescence provides an insight into photochemical and carbon sequestration processes within vegetation. Detection of Chlorophyll fluorescence has been well understood in the laboratory and field measurement. Fluorescence retrieval methods were applied in and around the atmospheric absorption bands 02B (Red wavelength) approximately 690 nm and 02A (Far red wavelengths) 740 nm. Hyperion satellite images were acquired for the years 2012 to 2015 in different seasons. Atmospheric corrections were applied using the 6S Model. The Fraunhofer Line Discrimanator (FLD) method was applied for retrieval of SIF from the Hyperion images by measuring the signal around the absorption bands in both vegetated and non vegetated land cover types. Absorption values were extracted in all the selected bands and the fluorescence signal was detected. The relationships between NDVI and Fluorescence derived from the satellite images are investigated to understand vegetation response within the absorption bands.

  13. Photoinhibition of Photosystems I and II Using Chlorophyll Fluorescence Measurements

    Science.gov (United States)

    Quiles, Maria Jose

    2005-01-01

    In this study the photoinhibition of photosystems (PS) I and II caused by exposure to high intensity light in oat ("Avena sativa," var Prevision) is measured by the emission of chlorophyll fluorescence in intact leaves adapted to darkness. The maximal quantum yield of PS II was lower in plants grown under high light intensity than in plants grown…

  14. Chlorophyll Fluorescence Analysis of Cyanobacterial Photosynthesis and Acclimation

    OpenAIRE

    Campbell, Douglas; Hurry, Vaughan; Adrian K Clarke; Gustafsson, Petter; Öquist, Gunnar

    1998-01-01

    Cyanobacteria are ecologically important photosynthetic prokaryotes that also serve as popular model organisms for studies of photosynthesis and gene regulation. Both molecular and ecological studies of cyanobacteria benefit from real-time information on photosynthesis and acclimation. Monitoring in vivo chlorophyll fluorescence can provide noninvasive measures of photosynthetic physiology in a wide range of cyanobacteria and cyanolichens and requires only small samples. Cyanobacterial fluore...

  15. Photochemical and photoelectrochemical quenching of chlorophyll fluorescence in photosystem II

    Czech Academy of Sciences Publication Activity Database

    Vredenberg, W.; Durchan, M.; Prášil, Ondřej

    2009-01-01

    Roč. 1787, č. 12 (2009), s. 1468-1478. ISSN 0005-2728 R&D Projects: GA ČR GA206/08/1683 Institutional research plan: CEZ:AV0Z50200510 Keywords : Chlorophyll a fluorescence * Photosystem II * Heterogeneity Subject RIV: EE - Microbiology, Virology Impact factor: 3.688, year: 2009

  16. Method for detecting copper complexes of chlorophyll in vegetable oils

    OpenAIRE

    Roca, María; Gallardo Guerrero, Lourdes; Gandul-Rojas, Beatriz

    2009-01-01

    [EN] The present invention relates to a method for detecting copper complexes of chlorophyll in vegetable oils and, more specifically, in olive oil. This method is of special interest for the food industry since it makes it possible to detect the presence, in the oil, of additives that are not pennitted by legislation.

  17. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto;

    In prospects of global climate change, heat stress is a rising constraint for the productivity of wheat (Triticum aestivum L.). It is a heat-susceptible crop beyond 17-23oC temperature throughout its phenological stages, flowering phase being the most sensitive stage. Chlorophyll a fluorescence...

  18. Laser-Induced Breakdown Spectroscopy and Chlorophyll a Flourescence Transients

    DEFF Research Database (Denmark)

    Frydenvang, Jens

    trustworthy results of a sufficient quality; something that remains a problem for many in-situ methods. In my PhD, I present my work with two such in-situ methods, Laser-Induced Breakdown Spectroscopy (LIBS) and OJIP transients, the rising part of chlorophyll a fluorescence transients from dark-adapted leaves....

  19. ECOHAB: Tester_P - Gulf of Mexico Chlorophyll - 1998-09 (NODC Accession 0000536)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chlorophyll a is a standard measure for phytoplankton biomass. Routinely, samples for extracted chlorophyll a values are filtered at sea, stored in liquid nitrogen,...

  20. The regulatory role of reversible phosphorylation in the chlorophyll degradation pathway

    Science.gov (United States)

    Senescence represents the final stage of plant development and is characterized by several processes including the systematic degradation of the photosynthetic apparatus and chlorophyll molecules inside chloroplasts. Normally, chlorophyll is catabolized to colorless compounds through a series of enz...

  1. ECOHAB: Tester_P - Gulf of Mexico Chlorophyll - 1998-09 (NODC Accession 0000537)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chlorophyll a is a standard measure for phytoplankton biomass. Routinely, samples for extracted chlorophyll a values are filtered at sea, stored in liquid nitrogen,...

  2. Toxicological effects of chlorpyrifos on growth, enzyme activity and chlorophyll a synthesis of freshwater microalgae.

    Science.gov (United States)

    Chen, Shangchao; Chen, Mindong; Wang, Zhuang; Qiu, Weijian; Wang, Junfeng; Shen, Yafei; Wang, Yajun; Ge, Shun

    2016-07-01

    This paper aims to acquire the experimental data on the eco-toxicological effects of agricultural pollutants on the aquatic plants and the data can support the assessment of toxicity on the phytoplankton. The pesticide of Chlorpyrifos used as a good model to investigate its eco-toxicological effect on the different microalgae in freshwater. In order to address the pollutants derived from forestry and agricultural applications, freshwater microalgae were considered as a good sample to investigate the impact of pesticides such as Chlorpyrifos on aquatic life species. Two microalgae of Chlorella pyrenoidosa and Merismopedia sp. were employed to evaluate toxicity of Chlorpyrifos in short time and long time by means of measuring the growth inhibition rate, the redox system and the content of chlorophyll a, respectively. In this study, the results showed that EC50 values ranging from 7.63 to 19.64mg/L, indicating the Chlorpyrifos had a relatively limited to the growth of algae during the period of the acute toxicity experiment. Moreover, when two kinds of algae were exposed to a medium level of Chlorpyrifos, SOD and CAT activities were importantly advanced. Therefore, the growth rate and SOD and CAT activities can be highly recommended for the eco-toxicological assessment. In addition, chlorophyll a also could be used as a targeted parameter for assessing the eco-toxicity of Chlorpyrifos on both Chlorella pyrenoidosa and Merismopedia sp. PMID:27314761

  3. Web camera as low cost multispectral sensor for quantification of chlorophyll in soybean leaves

    Science.gov (United States)

    Adhiwibawa, Marcelinus A.; Setiawan, Yonathan E.; Prilianti, Kestrilia R.; Brotosudarmo, Tatas H. P.

    2015-01-01

    Soybeans is one of main crops in Indonesia but the demand for soybeans is not followed by an increase in soybeans national production. One of the production limitation factor is the availability of lush cultivation area for soybeans plantation. Indonesian farners are usually grow soybeans in marginal cultivation area that requires soybeans varieties which tolerant with environmental stress such as drought, nutrition limitation, pest, disease and many others. Chlorophyll content in leaf is one of plant health indicator that can be used to determine environmental stress tolerant soybean varieties. However, there are difficulties in soybeans breeding research due to the manual acquisition of data that are time consume and labour extensive. In this paper authors proposed automatic system of soybeans leaves area and chlorophyll quantification based on low cost multispectral sensor using web camera as an indicator of soybean plant tollerance to environmental stress particularlly drought stress. The system acquires the image of the plant that is placed in the acquisition box from the top of the plant. The image is segmented using NDVI (Normalized Difference Vegetation Index) from image and quantified to yield an average value of NDVI and leaf area. The proposed system showed that acquired NDVI value has a strong relationship with SPAD value with r-square value 0.70, while the leaf area prediction has error of 18.41%. Thus the automation system can quantify plant data with good result.

  4. Fluorometric Techniques For The Measurement Of Oceanic Chlorophyll In The Support Of Remote Sensing

    OpenAIRE

    Smith, Raymond C; Baker, Karen S.; Dustan, Phillip

    1981-01-01

    Satellite imagery is now being used to estimate the near-surface chlorophyll concentration for large ocean areas. To assess the accuracy and precision of these remote sensing techniques, contemporaneous ship and satellite data for the determination of oceanic chlorophyll concentrations have been collected. Since chlorophyll fluorometry is a widely used technique for the determination of chlorophylls at sea, our analyses have led us to review the literature of fluorometry in order to re-examin...

  5. The effect of storage temperature of cucumber fruit on chlorophyll fluorescence

    OpenAIRE

    Ryszard Kosson

    2013-01-01

    The effect of three storage temperature levels: 12,5°C, 20°C, and 1,5°C on basic indexes of chlorophyll fluorescence of cucumber fruits was studied. The greenhouse grown cucumber fruits cv. Wiktor F1 were stored in perforated polyethylene bags or without packages. The minimum chlorophyll fluorescence (Fo), maximum chlorophyll fluorescence (Fm), variable chlorophyll fluorescence (Fv) and relative variable fluorescence (Fv/Fm) of the cucumber peel were measured. Relative variable fluorescence ...

  6. Transfer of Chlorophyll Pigments from an Oily Matrix to the Instestinal Epithelial Cells

    OpenAIRE

    Gandul-Rojas, Beatriz; Gallardo Guerrero, Lourdes; Mínguez Mosquera, María Isabel

    2008-01-01

    The present work is focused on examining the factors affecting the transfer of chlorophylls from an oily food matrix to the intestinal epithelial cells during the digestive process. It was studied both chlorophyll a (Chl a) and chlorophyll b (Chl b) as the major chlorophyll derivatives present in processed vegetables common at the diet: pheophytin a (Phy a), pheophytin b (Phy b), pyropheophytin a (Pyphy a), pheophorbide a (Pho a) and pyropheophorbide a (Pypho a).

  7. Long-term structural canopy changes sustain net photosynthesis per ground area in high arctic Vaccinium uliginosum exposed to changes in near-ambient UV-B levels.

    Science.gov (United States)

    Boesgaard, Kristine S; Albert, Kristian R; Ro-Poulsen, Helge; Michelsen, Anders; Mikkelsen, Teis N; Schmidt, Niels M

    2012-08-01

    Full recovery of the ozone layer is not expected for several decades and consequently, the incoming level of solar ultraviolet-B (UV-B) will only slowly be reduced. Therefore to investigate the structural and photosynthetic responses to changes in solar UV-B we conducted a 5-year UV-B exclusion study in high arctic Greenland. During the growing season, the gas exchange (H₂O and CO₂) and chlorophyll-a fluorescence were measured in Vaccinium uliginosum. The leaf dry weight, carbon, nitrogen, stable carbon isotope ratio, chlorophyll and carotenoid content were determined from a late season harvest. The net photosynthesis per leaf area was on average 22% higher in 61% reduced UV-B treatment across the season, but per ground area photosynthesis was unchanged. The leaf level increase in photosynthesis was accompanied by increased leaf nitrogen, higher stomatal conductance and F(v)/F(m). There was no change in total leaf biomass, but reduction in total leaf area caused a pronounced reduction of specific leaf area and leaf area index in reduced UV-B. This demonstrates the structural changes to counterbalance the reduced plant carbon uptake seen per leaf area in ambient UV-B as the resulting plant carbon uptake per ground area was not affected. Thus, our understanding of long-term responses to UV-B reduction must take into account both leaf level processes as well as structural changes to understand the apparent robustness of plant carbon uptake per ground area. In this perspective, V. uliginosum seems able to adjust plant carbon uptake to the present amount of solar UV-B radiation in the High Arctic. PMID:22211955

  8. Terra Populus and DataNet Collaboration

    Science.gov (United States)

    Kugler, T.; Ruggles, S.; Fitch, C. A.; Clark, P. D.; Sobek, M.; Van Riper, D.

    2012-12-01

    Terra Populus, part of NSF's new DataNet initiative, is developing organizational and technical infrastructure to integrate, preserve, and disseminate data describing changes in the human population and environment over time. Terra Populus will incorporate large microdata and aggregate census datasets from the United States and around the world, as well as land use, land cover, climate and other environmental datasets. These data are widely dispersed, exist in a variety of data structures, have incompatible or inadequate metadata, and have incompatible geographic identifiers. Terra Populus is developing methods of integrating data from different domains and translating across data structures based on spatio-temporal linkages among data contents. The new infrastructure will enable researchers to identify and merge data from heterogeneous sources to study the relationships between human behavior and the natural world. Terra Populus will partner with data archives, data producers, and data users to create a sustainable international organization that will guarantee preservation and access over multiple decades. Terra Populus is also collaborating with the other projects in the DataNet initiative - DataONE, the DataNet Federation Consortium (DFC) and Sustainable Environment-Actionable Data (SEAD). Taken together, the four projects address aspects of the entire data lifecycle, including planning, collection, documentation, discovery, integration, curation, preservation, and collaboration; and encompass a wide range of disciplines including earth sciences, ecology, social sciences, hydrology, oceanography, and engineering. The four projects are pursuing activities to share data, tools, and expertise between pairs of projects as well as collaborating across the DataNet program on issues of cyberinfrastructure and community engagement. Topics to be addressed through program-wide collaboration include technical, organizational, and financial sustainability; semantic

  9. Petri Nets and Semantics of System Descriptions

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kyng, Morten

    1982-01-01

    This paper discusses the use of Petri nets as a semantic tool in the design of languages and in the construction and analysis of system descriptions. The topics treated are: Languages based on nets. The problem of time in nets. Nets and related models. Nets and formal semantics. Parallel program...

  10. Pro asynchronous programming with .NET

    CERN Document Server

    Blewett, Richard; Ltd, Rock Solid Knowledge

    2014-01-01

    Pro Asynchronous Programming with .NET teaches the essential skill of asynchronous programming in .NET. It answers critical questions in .NET application development, such as: how do I keep my program responding at all times to keep my users happy how do I make the most of the available hardware how can I improve performanceIn the modern world, users expect more and more from their applications and devices, and multi-core hardware has the potential to provide it. But it takes carefully crafted code to turn that potential into responsive, scalable applications.With Pro Asynchronous Programming

  11. Portable chlorophyll meter (PCM-502) values are related to total chlorophyll concentration and photosynthetic capacity in papaya (Carica papaya L.)

    Science.gov (United States)

    This study was carried out to verify the practical use of the portable chlorophyll meter-PCM502 (PCM) in two papaya cultivars with contrasting green coloring of the leaf blade (‘Golden’: yellowish-green; ‘Solo’: dark green). The relationship was studied between the photosynthetic process and leaf n...

  12. Integrating Biology into the General Chemistry Laboratory: Fluorometric Analysis of Chlorophyll "a"

    Science.gov (United States)

    Wesolowski, Meredith C.

    2014-01-01

    A laboratory experiment that introduces fluorometry of chlorophyll "a" at the general chemistry level is described. The use of thin-layer chromatography to isolate chlorophyll "a" from spirulina and leaf matter enables quantification of small amounts of chlorophyll "a" via fluorometry. Student results were reasonably…

  13. Sonnenlicht-induzierte Chlorophyll-Fluoreszenz im Tagesgang in Nutzpflanzenbeständen

    OpenAIRE

    Idelberger, Claudia

    2015-01-01

    Im Rahmen der Fernerkundung per Spektrometermessungen wurde die sonnenlicht-induzierte Chlorophyll-Fluoreszenz zur Feststellung des Photosynthesestatus eines Pflanzenbestandes untersucht. Aus den kinetischen Mengenverschiebungen von sonnenlicht-induzierter Chlorophyll-Fluoreszenz und Photosynthese konnte in Abdunklungsversuchen nachgewiesen werden, dass beide Outputs des Photosystems II sind. Die sonnenlicht-induzierte Chlorophyll-Fluoreszenz unterliegt einem vor allem lichtabhängigen Tagesga...

  14. Assessment of salt tolerance of some newly developed and candidate wheat (triticum aestivum l.) cultivars using gas exchange and chlorophyll fluorescence attributes

    International Nuclear Information System (INIS)

    The present study was aimed to assess salt tolerance of some newly developed and candidate cultivars of wheat using gas exchange and chlorophyll fluorescence parameters. Ten wheat cultivars including five newly developed (S-24, Saher-2006, Fsd-2008, Lasani and Inqlab-91) and five candidate (P .B-18, M.P-65, S.H-20, AARI-10 and G.A-20) were grown in sand culture. Salt stress (150 mM NaCl in Hoagland's nutrient solution) was applied at the seedling stage. A significant reduction in plant biomass production was recorded in all wheat cultivars. Cultivars S-24, Saher-2006 and Fsd-2008 showed less reduction in biomass production as compared with the other cultivars. Different gas exchange attributes such as leaf net photosynthetic rate (A), transpiration rate ( E), and stomatal conductance (gs) were also adversely affected due to salt stress and were positively associated with the plant biomass production of the genotypes under saline stress. More negative effects in relation to these gas exchange attributes were recorded in cvs. Lasani, G.A-20 and ARRI-10 than those in the other cultivars. Leaf maximum chlorophyll fluorescence (Fm), maximum fluorescence at steady state (Fms ), and photochemical fluorescence quenching (Qp) increased while maximum quantum yield (Fv/Fm), quantum yield of electron transport (Qp), electron transport rate ( ETR ) and non-photochemical quenching (Qn) decreased due to imposition of salt stress. The adverse effects of salt stress on these chlorophyll fluorescence attributes were minimum in cultivars S-24, Saher-2006 and Fsd-2008. A significant positive correlation was recorded between biomass production, different gas exchange attributes and chlorophyll fluorescence parameters. Overall, cvs. S-24, Saher-2006 and Fsd-2008 were ranked as salt tolerant on the basis of their performance in biomass production, gas exchange attributes and chlorophyll fluorescence parameters. (author)

  15. An assessment of phytoplankton primary productivity in the Arctic Ocean from satellite ocean color/in situ chlorophyll-a based models

    Science.gov (United States)

    Lee, Younjoo J.; Matrai, Patricia A.; Friedrichs, Marjorie A. M.; Saba, Vincent S.; Antoine, David; Ardyna, Mathieu; Asanuma, Ichio; Babin, Marcel; Bélanger, Simon; Benoît-Gagné, Maxime; Devred, Emmanuel; Fernández-Méndez, Mar; Gentili, Bernard; Hirawake, Toru; Kang, Sung-Ho; Kameda, Takahiko; Katlein, Christian; Lee, Sang H.; Lee, Zhongping; Mélin, Frédéric; Scardi, Michele; Smyth, Tim J.; Tang, Shilin; Turpie, Kevin R.; Waters, Kirk J.; Westberry, Toby K.

    2015-09-01

    We investigated 32 net primary productivity (NPP) models by assessing skills to reproduce integrated NPP in the Arctic Ocean. The models were provided with two sources each of surface chlorophyll-a concentration (chlorophyll), photosynthetically available radiation (PAR), sea surface temperature (SST), and mixed-layer depth (MLD). The models were most sensitive to uncertainties in surface chlorophyll, generally performing better with in situ chlorophyll than with satellite-derived values. They were much less sensitive to uncertainties in PAR, SST, and MLD, possibly due to relatively narrow ranges of input data and/or relatively little difference between input data sources. Regardless of type or complexity, most of the models were not able to fully reproduce the variability of in situ NPP, whereas some of them exhibited almost no bias (i.e., reproduced the mean of in situ NPP). The models performed relatively well in low-productivity seasons as well as in sea ice-covered/deep-water regions. Depth-resolved models correlated more with in situ NPP than other model types, but had a greater tendency to overestimate mean NPP whereas absorption-based models exhibited the lowest bias associated with weaker correlation. The models performed better when a subsurface chlorophyll-a maximum (SCM) was absent. As a group, the models overestimated mean NPP, however this was partly offset by some models underestimating NPP when a SCM was present. Our study suggests that NPP models need to be carefully tuned for the Arctic Ocean because most of the models performing relatively well were those that used Arctic-relevant parameters.

  16. Two-photon excited fluorescence from higher electronic states of chlorophylls in photosynthetic antenna complexes a new approach to detect strong excitonic chlorophyll a/b coupling

    CERN Document Server

    Leupold, D; Ehlert, J; Irrgang, K D; Renger, G; Lokstein, H

    2002-01-01

    Stepwise two-photon excitation of chlorophyll a and b in the higher plant main light-harvesting complex (LHC II) and the minor complex CP29 (as well as in organic solution) with 100-fs pulses in the Q/sub y/ region results in a weak blue fluorescence. The dependence of the spectral shape of the blue fluorescence on excitation wavelength offers a new approach to elucidate the long-standing problem of the origin of spectral "chlorophyll forms" in pigment-protein complexes, in particular the characterization of chlorophyll a/b-heterodimers. As a first result we present evidence for the existence of strong chlorophyll a/b-interactions (excitonically coupled transitions at 650 and 680 nm) in LHC II at ambient temperature. In comparison with LHC II, the experiments with CP29 provide further evidence that the lowest energy chlorophyll a transition (at ~680 nm) is not excitonically coupled to chlorophyll b. (22 refs).

  17. Steady-state chlorophyll fluorescence (Fs) as a tool to monitor plant heat and drought stress

    Science.gov (United States)

    Cendrero Mateo, M.; Carmo-Silva, A.; Salvucci, M.; Moran, S. M.; Hernandez, M.

    2012-12-01

    Crop yield decreases when photosynthesis is limited by heat or drought conditions. Yet farmers do not monitor crop photosynthesis because it is difficult to measure at the field scale in real time. Steady-state chlorophyll fluorescence (Fs) can be used at the field level as an indirect measure of photosynthetic activity in both healthy and physiologically-perturbed vegetation. In addition, Fs can be measured by satellite-based sensors on a regular basis over large agricultural regions. In this study, plants of Camelina sativa grown under controlled conditions were subjected to heat and drought stress. Gas exchange and Fs were measured simultaneously with a portable photosynthesis system under light limiting and saturating conditions. Results showed that Fs was directly correlated with net CO2 assimilation (A) and inversely correlated with non-photochemical quenching (NPQ). Analysis of the relationship between Fs and Photosynthetically Active Radiation (PAR) revealed significant differences between control and stressed plants that could be used to track the status, resilience, and recovery of photochemical processes. In summary, the results provide evidence that Fs measurements, even without normalization, are an easy means to monitor changes in plant photosynthesis, and therefore, provide a rapid assessment of plant stress to guide farmers in resource applications. Figure1. Net CO2 assimilation rate (A) of Camelina sativa plants under control conditions and after heat stress exposure for 1 or 3 days (1d-HS and 3d-HS, respectively) (right) and control, drought and re-watering conditions (left). Conditions for infra-red gas analysis were: reference CO2 = 380 μmol mol-1, PPFD = 500 μmol m-2 s-1 and Tleaf set to 25°C (control, drought and re-water) or 35°C (HS). Different letters denote significant differences at the α=0.05 level. Values are means±SEM (n=10). Figure 2. Stable chlorophyll fluorescence (Fs) of Camelina sativa plants under control conditions and

  18. Responses of Transgenic Tobacco Plants with Increased Proline Content to Drought and/or Heat Stress

    Czech Academy of Sciences Publication Activity Database

    Pospíšilová, Jana; Haisel, Daniel; Vaňková, Radomíra

    2011-01-01

    Roč. 2, č. 3 (2011), s. 318-324. ISSN 2158-2742 R&D Projects: GA ČR GA522/09/2058 Institutional research plan: CEZ:AV0Z50380511 Keywords : Carotenoids * Chlorophyll * Net Photosynthetic Rate Subject RIV: ED - Physiology http://www.scirp.org/journal/PaperInformation.aspx?paperID=7576

  19. Understanding Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Salom, Jaume; Widén, Joakim; Candanedo, José;

    2011-01-01

    Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures and by...... incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid....... This paper presents and categorizes quantitative indicators suitable to describe both aspects of the building’s performance. These indicators, named LMGI - Load Matching and Grid Interaction indicators, are easily quantifiable and could complement the output variables of existing building simulation...

  20. KM3NeT

    CERN Multimedia

    KM3NeT is a large scale next-generation neutrino telescope located in the deep waters of the Mediterranean Sea, optimized for the discovery of galactic neutrino sources emitting in the TeV energy region.

  1. The Importance of Safety Nets

    OpenAIRE

    Kim, Jim Yong

    2014-01-01

    Jim Yong Kim, President of the World Bank Group discusses the importance of safety nets and social protection that countries provide to their citizens. He announces supporting for Mexico’s second-generation safety net program PROSPERA, which provides a financial cushion to poor people, allowing them to achieve a higher level of health and security and giving them the chance to learn skills and to find go...

  2. The Economics of Net Neutrality

    OpenAIRE

    Hahn, Robert W.; Wallsten, Scott

    2006-01-01

    This essay examines the economics of "net neutrality" and broadband Internet access. We argue that mandating net neutrality would be likely to reduce economic welfare. Instead, the government should focus on creating competition in the broadband market by liberalizing more spectrum and reducing entry barriers created by certain local regulations. In cases where a broadband provider can exercise market power the government should use its antitrust enforcement authority to police anticompetitiv...

  3. Process of Petri Nets Extension

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To describe the dynamic semantics for the network computing, the concept on process is presented based on the semantic model with variable, resource and relation. Accordingly, the formal definition of process and the mapping rules from the specification of Petri nets extension to process are discussed in detail respectively. Based on the collective concepts of process, the specification of dynamic semantics also is constructed as a net system. Finally, to illustrate process intuitively, an example is specified completely.

  4. Practical .NET for financial markets

    CERN Document Server

    Shetty, Vivek

    2006-01-01

    This book provides fascinating insight into the nature and operation of Financial (Equity) markets and the singular demands and challenges placed on technology solutions in this environment. It then takes an in-depth look at how these challenges can be addressed using Microsoft .NET technology. Each chapter starts with a detailed explanation of a specific and ubiquitous business requirement in Equity market applications, and then the particular features of the.NET framework that can be used to meet that requirement

  5. Analisis Determinan Net Ekspor Indonesia

    OpenAIRE

    Daulay, Rahmawaty

    2010-01-01

    This study is to analyzing empirically among Indonesia GDP, trade partnership GDP (Malaysia, Singapore, US and Thailand) and real exchange rate toward Indonesia Net Export. To find out which one from those three variables is significant in order to fluctuating (increasing or decreasing) Indonesia Net Export either in the short run or in the long run. Data collection is obtained using secondary data, namely Indonesia GDP, Malaysia GDP, Singapura GDP, US GDP, Thailand GDP and real exchange rate...

  6. Petri Nets And Algebraic Specifications

    International Nuclear Information System (INIS)

    The present report covers part of the work carried out in connection to the co-operative project between ENEA and the OECD Halden Reactor Project on graphical and formal methods for software specification. One of the project assignments has been to investigate how graphical descriptions can be supported by the algebraic specification language and associated tool (the HRP Prover) developed at the Halden Project. Since many graphical description languages can be translated to Petri nets, the focus of the investigations has been put on the translation of these nets into algebraic specification. The report introduces two related classes of algebraic specifications, and defines a notion of equivalence between them. It is demonstrated how these two classes provide a suitable framework for the translation of many different types of Petri nets into algebraic specification. It is also demonstrated how this translation makes it possible to analyse the nets with techniques established for algebraic specification, illustrated through the use of the HRP Prover. The exposition in the report contributes to a clarification about the relationship between Petri nets and algebraic specifications. Furthermore, it indicates the extent to which graphical descriptions can be used to explain the meaning of algebraic specifications to non experts. The report also reviews applications of Petri nets related to nuclear power. These include fault diagnosis and fault detection in nuclear reactors, fault tolerance in nuclear reactor protection systems, and modelling of work flow in nuclear waste management. (author)

  7. [Retrieving for chlorophyll-a concentration and suspended substance concentration based on HJ-1A HIS image].

    Science.gov (United States)

    Yang, Ting; Zhang, Hui; Wang, Qiao; Zhao, Qiao-Hua

    2011-11-01

    Based on geometry correction using ERDAS software and radiation correction using 6S model for HJ-1A hyper-spectrum image (HSI) on May 2 in 2010 and the analysis of spectrum for water data and spectral data of hyper-spectrum image, this paper processes original spectrum data of 28 sample points using method of normalization and method of first-order derivation. Single-band and band combination are selected to establish inversion models of the concentration of chlorophyll-a and solid suspensions. Choosing the model with biggest correlation coefficient, the spatial distribution map of the concentration of chlorophyll-a and solid suspensions content in Taihu Lake is acquired. The research results show: Band-73 of hyper-spectrum image which has been normalized shows the biggest correlation coefficient of the concentration of chlorophyll-a, remote sensing sediment parameter shows the biggest correlation coefficient of the concentration of solid suspensions, the result is consistent with analysis of spectral data of hyper-spectrum image. Average relative errors of predicted and measured values are within 30 percent. Spatial distribution map of water quality is consistent with the result of field surveys. Therefore, based on reference of the analysis of sensitive band of spectrum for water data, HJ-1A hyper-spectrum image can give quantitative estimation of water quality parameters in Taihu Lake. PMID:22295614

  8. Effects of space environment on chlorophyll fluorescence and photosynthesis characteristics of wheat

    International Nuclear Information System (INIS)

    The effects of the space environment on the chlorophyll fluorescence parameters and photosynthesis characteristics of wheat cultivars, Xinong 1043 M1 and Shaan253 M1, were studied. The results showed that the decrement of contents of PS II primary photochemical efficiency (Fv/Fm), potential activity (Fv/F0), photochemical quenching coefficient (qP) and photosynthesis rate (Pn) were less than that of control, increment of non-photochemical quenching coefficient (qN) were more than that of control. The results suggested that photosynthetic apparatus were damaged, photosynthetic electron transport, photosynthetic primary reaction were inhibited, rate of photosynthesis decreased and growth of M1 plant were retarded, which leading to thousand kernel weights decreased. (authors)

  9. Das Projekt NetAcademy on Mediamanagement, Schlussbericht der Phase 4

    OpenAIRE

    Schmid-isler, Salome; Wittig Christ, Doerte

    2000-01-01

    Schlussbericht des Projektes NetAcademy zuhanden der Bertelsmann Stiftung und der Heinz Nixdorf Stiftung, =mcm Institute, Universität St. Gallen. - The NetAcademy on Media Management (NA on MM), like the other parts of the NetAcademy Universe platform, received a significant upswing in the past year. The most obvious proofs of this boom are the fast growing content and the considerable increase in the numbers of visitors. Here the final report.

  10. Cylindrical aggregates of chlorophylls studied by small-angle neutron scatter

    International Nuclear Information System (INIS)

    Neutron small-angle scattering has demonstrated tubular chlorophyll aggregates formed by self-assembly of a variety of chlorophyll types in nonpolar solvents. The size and other properties of the tubular aggregates can be accounted for by stereochemical properties of the chlorophyll molecules. Features of some of the structures are remarkably similar to light harvesting chlorophyll complexes in vivo, particularly for photosynthetic bacteria. These nanotube chlorophyll structures may have applications as light harvesting biomaterials where efficient energy transfer occurs from an excited state which is highly delocalized

  11. Cylindrical aggregates of chlorophylls studied by small-angle neutron scatter

    Energy Technology Data Exchange (ETDEWEB)

    Worcester, D.L. [Univ. of Missouri, Columbus, MO (United States); Katz, J.J. [Argonne National Laboratory, IL (United States)

    1994-12-31

    Neutron small-angle scattering has demonstrated tubular chlorophyll aggregates formed by self-assembly of a variety of chlorophyll types in nonpolar solvents. The size and other properties of the tubular aggregates can be accounted for by stereochemical properties of the chlorophyll molecules. Features of some of the structures are remarkably similar to light harvesting chlorophyll complexes in vivo, particularly for photosynthetic bacteria. These nanotube chlorophyll structures may have applications as light harvesting biomaterials where efficient energy transfer occurs from an excited state which is highly delocalized.

  12. Production of Liquid Chlorophyll from The Leaves of Green Grass Jelly (Premna oblongifolia Merr.)

    OpenAIRE

    Novelina Novelina; Tuty Anggraini; Rudi Hermansyah

    2015-01-01

    Chlorophyll is known to be used as a natural dye. The last few years it is known that chlorophyll has an important role as a source of antioxidants that are good for health. The availability of sources of chlorophyll in Indonesia is very large, one of which is the green grass jelly leaves (Premna obliongifolia Merr). The research objective is to get grass jelly leaf extract as a source of chlorophyll and know the characteristics of the resulting extract chlorophyll. The process of extraction ...

  13. Determination of chlorophyll a concentrations and phytoplankton primary production in New England estuarine waters using ocean color remote sensing from low-flying aircraft

    Science.gov (United States)

    Keith, Darryl Joel

    modeled chlorophyll concentrations in Narragansett Bay. Results indicated that the SeaWiFS OC4v4 ocean color model had the best performance based on statistical and graphic criteria. In Chapter III, the magnitude and distribution of daily net phytoplankton primary production for Narragansett Bay were estimated by applying the Chesapeake Bay Production Model-1 (CBPM-1) to aircraft derived chlorophyll a and sea surface temperature data.

  14. Chlorophyll a and primary production in the northeastern Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    HEN Xingqun; LIN Rongeheng

    2008-01-01

    The primary production and chlorophyll a concentration of picoplankton (0.2~2μm),nanoplankton (2~20 μm) and micro- plankton (20~200 μm) are described in the northeastern Pacific Ocean near the Hawaii Islands during the six survey cruises from 1996 to 2003:DY85-4,DY95-7,DY95-8,DY95-10,DY105-11 and DY105-12.14.The primary production of carbon was in range from 76.8 to 191.9 mg/(m2·d) with an average of 116.1 mg/( m2·d) in the east region,and from 73.1 to 222.5 mg/(m2·d) with an average of 127.1 mg/( m2·d) in the west region,similar to the other oligotrophic regions of the Pacific Ocean investigated.The chlorophyll a concentration was about 0.1 mg/m3 from the surface to the 50 m depth,about 0.2-0.4 mg/m3from 50 to 100 m,and gradually decreased below the 100 m depth.The picoplankton accounted for more than 70% of the total chlorophyll a in the upper layer (surface to 125 m),but it decreased to less than 50% in depth below 125 m.The na- noplankton and microplankton combined only accounted for less than 30% of the total chlorophyll a in the upper layer,but showed a more even vertical distribution.

  15. Regional variability among nonlinear chlorophyll-phosphorus relationships in lakes

    Science.gov (United States)

    Filstrup, Christopher T.; Wagner, Tyler; Soranno, Patricia A.; Stanley, Emily H.; Stow, Craig A.; Webster, Katherine E.; Downing, John A.

    2014-01-01

    The relationship between chlorophyll a (Chl a) and total phosphorus (TP) is a fundamental relationship in lakes that reflects multiple aspects of ecosystem function and is also used in the regulation and management of inland waters. The exact form of this relationship has substantial implications on its meaning and its use. We assembled a spatially extensive data set to examine whether nonlinear models are a better fit for Chl a—TP relationships than traditional log-linear models, whether there were regional differences in the form of the relationships, and, if so, which regional factors were related to these differences. We analyzed a data set from 2105 temperate lakes across 35 ecoregions by fitting and comparing two different nonlinear models and one log-linear model. The two nonlinear models fit the data better than the log-linear model. In addition, the parameters for the best-fitting model varied among regions: the maximum and lower Chl aasymptotes were positively and negatively related to percent regional pasture land use, respectively, and the rate at which chlorophyll increased with TP was negatively related to percent regional wetland cover. Lakes in regions with more pasture fields had higher maximum chlorophyll concentrations at high TP concentrations but lower minimum chlorophyll concentrations at low TP concentrations. Lakes in regions with less wetland cover showed a steeper Chl a—TP relationship than wetland-rich regions. Interpretation of Chl a—TP relationships depends on regional differences, and theory and management based on a monolithic relationship may be inaccurate.

  16. Associations between chlorophyll a and various microcystin health advisory concentrations

    OpenAIRE

    Hollister, Jeffrey W.; Kreakie, Betty J.

    2016-01-01

    Archived source code (as an R package), data for the manuscript "Associations between chlorophyll a and various microcystin health advisory concentrations"  published in F1000Research (http://f1000research.com/articles/5-151/)  Abstract:  Cyanobacteria harmful algal blooms (cHABs) are associated with a wide range of adverse health effects that stem mostly from the presence of cyanotoxins. To help protect against these impacts, several health advisory levels ha...

  17. The Application of Variable Chlorophyll Fluorescenceto Microphytobenthic Biofilms

    OpenAIRE

    Perkins, Rupert G.; Kromkamp, Jacco C.; Serôdio, Joao; Lavaud, Johann; Jesus, Bruno; Mouget, Jean-Luc; Lefebvre, Sébastien; Forster, R. M.

    2010-01-01

    Community assemblages of diatoms, green algae andcyanobacteria comprise the microphytobenthos (MPB),which inhabit benthic sediment ecosystems (Admiraal1984; Underwood and Kromkamp 1999; Consalvey et al. 2004). Particular attention has been paid to theanalysis of intertidal soft sediment systems, e.g. cohesivemudflat and sandy substrata typical of estuarine habitats.Variable chlorophyll fluorescence has been applied tothese systems since the 1990s, in an attempt to investigatethe primary produ...

  18. Chlorophyll and carotenoid pigments in solar saltern microbial mats

    Science.gov (United States)

    Villanueva, Joan; Grimalt, Joan O.; de Wit, Rutger; Keely, Brendan J.; Maxwell, James R.

    1994-11-01

    The distributions of carotenoids, chlorophylls, and their degradation products have been studied in two microbial mat systems developed in the calcite and calcite/gypsum evaporite domains of a solar saltern system. Phormidium valderianum and Microcoleus chthonoplastes are the dominant cyanobacterial species, respectively, and large amounts of Chloroflexus-like bacteria occur in the carbonate/gypsum mat. In both systems, the major pigments are chlorophyll a, zeaxanthin, β-carotene and myxoxanthophyll, which originate from these mat-building cyanobacteria. This common feature contrasts with differences in other pigments that are specific for each mat community. Thus, chlorophyll c and fucoxanthin, reflecting diatom inputs, are only found in the calcite mat, whereas the calcite/gypsum mat contains high concentrations of bacteriochlorophylls c produced by the multicellular green filamentous bacteria. In both cases, the depth concentration profiles (0-30 and 0-40 mm) show a relatively good preservation of the cyanobacterial carotenoids, zeaxanthin, β-carotene, myxoxanthophyll, and echinenone. This contrasts with the extensive biodegradation of cyanobacterial remains observed microscopically. Fucoxanthin in the calcite mat is also transformed at a faster rate than the cyanobacterial carotenoids. Chlorophyll a, the major pigment in both mats, exhibits different transformation pathways. In the calcite/gypsum mat, it is transformed via C-13 2 carbomethoxy defunctionalization prior to loss of the phytyl chain, leading to the formation of pyrophaeophytin a and, subsequently, pyrophaeophorbide a. On the other hand, the occurrence of the enzyme chlorophyllase, attributed to diatoms in the calcite mat, gives rise to extensive phytyl hydrolysis, with the formation of chlorophyllide a, pyrophaeophorbide a and, in minor proportion, phaeophorbide a. Studies of the sources of the photosynthetic pigments and of their transformation pathways in such simplified ecosystems provide a

  19. Quantifying global marine isoprene fluxes using MODIS chlorophyll observations

    OpenAIRE

    Palmer, P.I.; Shaw, S. L.

    2005-01-01

    We report global distributions of marine isoprene flux, whose source is estimated by combining an empirical relationship for isoprene production rate with MODIS satellite chlorophyll observations from 2001. We use a steady-state water column model including losses to chemistry, bacteria, and air-sea exchange. Physical mixing is a negligible sink. Flux estimates range from 107–109 molecules cm−2s−1, with considerable spatial and temporal variability, resulting in a global annual total of 0.1 T...

  20. Declining ocean chlorophyll under unabated anthropogenic CO2 emissions

    International Nuclear Information System (INIS)

    Photosynthetic assimilation of carbon dioxide and inorganic nutrients by phytoplankton constitutes a necessary prerequisite for sustaining marine life. This process is tightly linked to the concentration of chlorophyll in the ocean's euphotic zone. According to a recent field study marine chlorophyll(a) concentrations have declined over the last century with an estimated global rate of 1.0% of the global median per year. Here we attempt to identify possible mechanisms which could explain such trends. We explore these questions using an ocean general circulation model forced with documented historic and projected future anthropogenic emissions of carbon dioxide according to the IPCC SRES A1FI emission scenario until the year 2100. We further extend the time period covered by the A1FI scenario by assuming a linear decline in emissions from 2100 to 2200 and keeping them at zero levels until 2400. Our numerical simulations reveal only weak reductions in chlorophyll(a) concentrations during the twentieth century, but project a 50% decline between 2000 and 2200. We identify a local and a remotely acting mechanism for this reduction in the North Atlantic: (I) increased sea surface temperatures reduce local deep mixing and, hence, reduce the nutrient supply from waters at intermediate depths; (II) a steady shoaling of the Atlantic overturning cell tends to transport increasingly nutrient depleted waters from the Southern Hemisphere toward the north, leading to further diminishment of nutrient supply. These results provide support for a temperature-driven decline in ocean chlorophyll(a) and productivity, but suggest that additional mechanisms need to be invoked to explain observed declines in recent decades.

  1. Eddy effects on surface chlorophyll in the northern South China Sea: Mechanism investigation and temporal variability analysis

    Science.gov (United States)

    He, Qingyou; Zhan, Haigang; Cai, Shuqun; Li, Zimu

    2016-06-01

    The effects of eddies on surface chlorophyll (CHL) in the northern South China Sea are investigated by analyzing the long-term composite averages of CHL anomalies between 1998 and 2011 that were associated with eddies. CHL anomalies that are modulated by different dynamical processes are distinguished and discussed separately. The positive CHL anomalies within cyclonic eddies are generally larger in magnitude than the negative CHL anomalies within anticyclonic eddies, which implies a net increase in chlorophyll induced by eddy activities. At least two dynamical mechanisms, eddy pumping and eddy stirring, are found to play important roles in the CHL anomalies. The influence of eddy pumping is restricted by the mixed layer depth and its distance from deep nutriclines. Thus, the associated CHL anomalies are most apparent in winter and diminish in the following summer for both cyclonic and anticyclonic eddies. The inter-annual variation in the CHL anomalies within cyclonic eddies is modulated by the eddy intensity and exhibits a close relationship with the El Niño-Southern Oscillation. Meanwhile, the variation within anticyclonic eddies might be affected by the background CHL, with a downward trend during the study period. This work provides an overview to the nature and temporal variations in CHL anomalies that are associated with eddies in the northern South China Sea.

  2. The Economics of Net Neutrality: Implications of Priority Pricing in Access Networks

    OpenAIRE

    Wiewiorra, Lukas

    2012-01-01

    This work systematically analyzes Net Neutrality from an economic point of view. To this end a framework is developed which helps to structure the Net Neutrality debate. Furthermore, the introduction of prioritization is studied by analyzing potential effects of Quality of Service (QoS) on Content and Service Providers (CSPs) and Internet Users (IUs).

  3. Oceanographic profile Chlorophyll, zooplankton biomass and other measurements collected using net in the SE ATLANTIC in 1969 (NODC Accession 0000930)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hutchings, L. 1988. Horozontal distribution of mesozooplankton in the Southern Benguela Current, 1969-1974. Investigational Report of the Sea Fisheries Research...

  4. Primerjava razvojnih modelov .NET MVC in .NET Web Forms

    OpenAIRE

    ROŽMAN, ANŽE

    2016-01-01

    Telekomunikacijska industrija se hitro razvija, zato pogosto pride do problema, ko obstoječa spletna aplikacija OMS ne nudi več zadostne podpore samim poslovnim zahtevam. OMS je spletna aplikacija, ki upravlja z naročili. Omogoča zajem, obdelavo in izvedbo naročil za uporabnike operaterskih storitev. Pri izgradnji nove spletne aplikacije OMS smo imeli v podjetju, ki za enega od slovenskih operaterjev deluje kot podizvajalec, dva možna razvojna modela ASP .NET Spletni obrazci in ASP .NET MVC,...

  5. SIGNALS REGARDING THE ISOLATION OF CHLOROPHYL-FREE ALGAE IN THE MILK OF SOME HEALTHY COWS AND SOME WITH MAMITTIS

    OpenAIRE

    OGNEAN, Laurent; Dana PUSTA; Oana, Liviu

    2002-01-01

    In the microbiological investigation, made on samples of normal; (n=412) and mastitic (n=482) milk, proceeded from eight dairy cows farm, in Transilvania, it was signal the presence of the algae without chlorophyl belonging to Prototheca, forming together with bacteria and fungi the micro flora of the mammary gland. The alga content of normal milk was signaled only in two farms (2.27%, respectively 1.21%), being established to 0.72%. In the case of mastitic milk the percentage of ...

  6. MEAT QUALITY AND CAECAL CONTENT CHARACTERISTICS OF RABBIT ACCORDING TO DIETARY CONTENT AND BOTANICAL ORIGIN OF STARCH

    OpenAIRE

    A. Nizza; Moniello, G.

    2000-01-01

    Abstract not available. Nizza, A.; Moniello, G. (2000). MEAT QUALITY AND CAECAL CONTENT CHARACTERISTICS OF RABBIT ACCORDING TO DIETARY CONTENT AND BOTANICAL ORIGIN OF STARCH. http://hdl.handle.net/10251/10264.

  7. Effect of Methanol on Photosynthesis and Chlorophyll Fluorescence of Flag Leaves of Winter Wheat

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yue-jin; YANG Yue-qin; LIANG Shan-shan; YI Xian-feng

    2008-01-01

    Photosynthesis and chlorophyll a fluorescence parameters, photochemical efficiency of PS II (Fv/Fm), photochemical quenching of PS II (qP), nonphotochemical quenching of PS II (NPQ), maximum activity of PS II (Fv/Fo) as well as electron transport rate (ETR), and quantum yield of PS II (ΦPS II) were measured on flag leaves of the winter wheat treated by methanol at different concentrations. The results revealed that photosynthesis was greatly improved by methanol, as indicated by higher photosynthetic rates and stomatal conductance. The enhancement effect of methanol on photosynthesis was maintained for 3-4 days. Different methanol concentration treatments also increased intercellular CO2 concentration and transpiration rates. No significant decline was found in Fv/Fm, Fv/Fo, and ΦPS II, which revealed no photoinhibition during methanol application in different methanol concentrations. Methanol showing no apparent inhibitory effects indicated higher potential photosynthetic capacity of flag leaves of winter wheat. However, the increase in photosynthesis was not followed by an increase in the photosynthetic activity (Fv/Fm), and fluorescence parameters did not indicate an improvement in intercellular CO2 concentration and PS II photochemical efficiency compared with the control, thereby encouraging us to propose that lower leaf temperatures caused by applied methanol would reduce both dark respiration and photorespiration (most importantly), thus, increasing net CO2 uptake and photosynthetic rates.

  8. TimeNET Optimization Environment

    Directory of Open Access Journals (Sweden)

    Christoph Bodenstein

    2015-12-01

    Full Text Available In this paper a novel tool for simulation-based optimization and design-space exploration of Stochastic Colored Petri nets (SCPN is introduced. The working title of this tool is TimeNET Optimization Environment (TOE. Targeted users of this tool are people modeling complex systems with SCPNs in TimeNET who want to find parameter sets that are optimal for a certain performance measure (fitness function. It allows users to create and simulate sets of SCPNs and to run different optimization algorithms based on parameter variation. The development of this tool was motivated by the need to automate and speed up tests of heuristic optimization algorithms to be applied for SCPN optimization. A result caching mechanism is used to avoid recalculations.

  9. AKTIVITAS ANTIOKSIDAN DAN KADAR FENOLIK TOTAL DARI GANGGANG MERAH (Gracilaria verrucosa L.) [Antioxidant Activity and Total Phenolic Content of Red Sea Weed (Gracilaria verrucosa L.)

    OpenAIRE

    Lydia Ninan Lestario*; Stefanli Sugiarto; K H Timotius

    2008-01-01

    The aims of this study were to compare the antioxidant activity and the total phenolic content of red sea weed (Gracilaria verrucosa L.) from extract of methanol, ethanol, acetone, chloroform and hexane; and the correlation between total phenolic content and the antioxidant activity of each extract; then to determine the chlorophyll a, chlorophyll b, and carotene content of each extract and their correlation with the free radical scavenging activity as well. The antioxidant activity were me...

  10. Normal-Phase Open Column versus Reversed-Phase High Performance Liquid Chromatography: Separation of Chlorophyll a and Chlorophyll b from their Diastereomers.

    Science.gov (United States)

    Schaber, Peter M.

    1985-01-01

    Background information, procedures used, and typical results obtained are provided for an experiment involving the separation of chlorophyll a and chlorophyll b from their diastereomers. Reasons why the experiment can be easily integrated into most laboratory curricula where high-performance liquid chromatography capabilities exist are given. (JN)

  11. LabraNet-verkon monitorointi

    OpenAIRE

    Sunnari, Jussi

    2010-01-01

    Opinnäytetyön tarkoituksena oli etsiä ja ottaa käyttöön Jyväskylän ammattikorkeakoulun Teknologia-yksikön Labra- Net-verkkoon uusi valvontaohjelmisto. LabraNet-verkko oli alunperin vain yksikön omassa tuotantokäytössä, mutta nykyään se kasvaa ja monipuolistuu nopeasti tarjoten palveluitaan muille yksiköille. Tästä johtuen vanha valvontaoh- jelmisto koettiin rajoittuneeksi, eikä se vastannut nykyajan vaatimuksia. Verkonvalvonnan tarkoitus on parantaa verkon luotettavuutta, ...

  12. Neural nets and chaotic carriers

    CERN Document Server

    Whittle, Peter

    2010-01-01

    ""Neural Nets and Chaotic Carriers"" develops rational principles for the design of associative memories, with a view to applying these principles to models with irregularly oscillatory operation so evident in biological neural systems, and necessitated by the meaninglessness of absolute signal levels. Design is based on the criterion that an associative memory must be able to cope with 'fading data', i.e., to form an inference from the data even as its memory of that data degrades. The resultant net shows striking biological parallels. When these principles are combined with the Freeman speci

  13. Implementing NetScaler VPX

    CERN Document Server

    Sandbu, Marius

    2014-01-01

    An easy-to-follow guide with detailed step-by step-instructions on how to implement the different key components in NetScaler, with real-world examples and sample scenarios.If you are a Citrix or network administrator who needs to implement NetScaler in your virtual environment to gain an insight on its functionality, this book is ideal for you. A basic understanding of networking and familiarity with some of the different Citrix products such as XenApp or XenDesktop is a prerequisite.

  14. Net4Care PHMR Library

    DEFF Research Database (Denmark)

    2014-01-01

    The Net4Care PHMR library contains a) A GreenCDA approach for constructing a data object representing a PHMR document: SimpleClinicalDocument, and b) A Builder which can produce a XML document representing a valid Danish PHMR (following the MedCom profile) document from the SimpleClinicalDocument......The Net4Care PHMR library contains a) A GreenCDA approach for constructing a data object representing a PHMR document: SimpleClinicalDocument, and b) A Builder which can produce a XML document representing a valid Danish PHMR (following the MedCom profile) document from the Simple...

  15. Retrieval of coniferous canopy chlorophyll content from high spatial resolution hyperspectral data

    Czech Academy of Sciences Publication Activity Database

    Malenovský, Zbyněk; Zurita-Milla, R.; Homolová, Lucie; Martin, E.; Schaepman, M.E.; Gastellu-Etchegory, J.P.; Pokorný, Radek; Clevers, J.G.P.W.

    2007 - (Schaepman, M.; Liang, S.; Groot, N.; Kneubühler, M.), s. 108-113 ISSN 1682-1777. - (Intl. Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. 36). [10th Intl. Symposium on Physical Measurements and Spectral Signatures in Remote Sensing. Davos (CH), 12.03.2007-14.03.2007] R&D Projects: GA MŠk 2B06068 Institutional research plan: CEZ:AV0Z60870520 Keywords : remote sensing * hyperspectral * high resolution * forestry * vegetation * estimation * retrieval * neural Subject RIV: GK - Forestry

  16. Stomatal Conductance and Chlorophyll Characteristics and Their Relationship with Yield of Some Cocoa Clones Under Tectona grandis, Leucaena sp., and Cassia surattensis.

    OpenAIRE

    Fakhrusy Zakariyya; Adi Prawoto

    2015-01-01

    An optimum physiological condition will support high yield and quality of cocoa production. The research was aimed to study the effects of stomatal conductance and chlorophyll content related to cocoa production under three shade regimes.This research was conducted in Kaliwining Experimental Station, elevation of 45 m above sea level with D climate type based on Schmidt & Fergusson. Cocoa trees which were planted in 1994 at a spacing of 3 X 3 m were used in the study planted by using spli...

  17. Professional ASP.NET 4.5 in C# and VB

    CERN Document Server

    Gaylord, Jason N; Rastogi, Pranav; Miranda, Todd; Hanselman, Scott

    2013-01-01

    The all-new approach for experienced ASP.NET professionals! ASP.NET is Microsoft's technology for building dynamically generated web pages from database content. Originally introduced in 2002, ASP.NET has undergone many changes in multiple versions and iterations as developers have gained a decade of experience with this popular technology. With that decade of experience, this edition of the book presents a fresh, new overhauled approach. A new focus on how to build ASP.NET sites and applications relying on field-tested reliable methodsIntegration of ""One A

  18. Chlorophyll Fluorescence Emissions of Vegetation Canopies From High Resolution Field Reflectance Spectra

    Science.gov (United States)

    Middleton, E. M.; Corp, L. A.; Daughtry, C. S. T.; Campbell, P. K. Entcheva

    2006-01-01

    A two-year experiment was performed on corn (Zea mays L.) crops under nitrogen (N) fertilization regimes to examine the use of hyperspectral canopy reflectance information for estimating chlorophyll fluorescence (ChlF) and vegetation production. Fluorescence of foliage in the laboratory has proven more rigorous than reflectance for correlation to plant physiology. Especially useful are emissions produced from two stable red and far-red chlorophyll ChlF peaks centered at 685V10 nm and 735V5 nm. Methods have been developed elsewhere to extract steady state solar induced fluorescence (SF) from apparent reflectance of vegetation canopies/landscapes using the Fraunhofer Line Depth (FLD) principal. Our study utilized these methods in conjunction with field-acquired high spectral resolution canopy reflectance spectra obtained in 2004 and 2005 over corn crops, as part of an ongoing multi-year experiment at the USDA/Agriculture Research Service in Beltsville, MD. A spectroradiometer (ASD-FR Fieldspec Pro, Analytical Spectral Devices, Inc., Boulder, CO) was used to measure canopy radiances 1 m above plant canopies with a 22deg field of view and a 0deg nadir view zenith angle. Canopy and plant measurements were made at the R3 grain fill reproductive stage on 3-4 replicate N application plots provided seasonal inputs of 280, 140, 70, and 28 kg N/ha. Leaf level measurements were also made which included ChlF, photosynthesis, and leaf constituents (photosynthetic pigment, carbon (C), and N contents). Crop yields were determined at harvest. SIF intensities for ChlF were derived directly from canopy reflectance spectra in specific narrowband regions associated with atmospheric oxygen absorption features centered at 688 and 760 nm. The red/far-red S F ratio derived from these field reflectance spectra successfully discriminated foliar pigment levels (e.g., total chlorophyll, Chl) associated with N application rates in both corn crops. This canopy-level spectral ratio was also

  19. Surgery for GEP-NETs

    DEFF Research Database (Denmark)

    Knigge, Ulrich; Hansen, Carsten Palnæs

    2012-01-01

    Surgery is the only treatment that may cure the patient with gastroentero-pancreatic (GEP) neuroendocrine tumours (NET) and neuroendocrine carcinomas (NEC) and should always be considered as first line treatment if R0/R1 resection can be achieved. The surgical and interventional procedures for GEP...

  20. Net Neutrality in the Netherlands

    NARCIS (Netherlands)

    N. van Eijk

    2014-01-01

    The Netherlands is among the first countries that have put specific net neutrality standards in place. The decision to implement specific regulation was influenced by at least three factors. The first was the prevailing social and academic debate, partly due to developments in the United States. The

  1. Banking Safety Nets: Information Issues

    OpenAIRE

    Jorge Ponce

    2006-01-01

    This paper synthesizes recent literature on the optimal design of banking safety nets. We focalize on information issues. In particular, we propose a mechanism to improve the incentives the Central Bank has to provide information to the Deposit Insurance Corporation. Such mechanism makes possible the implementation of the second-best allocation of the lender of last resort activity proposed by Repullo (2000).

  2. Net4Care PHMR Tutorial

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    Goal To demonstrate how to use the Net4Care PHMR builder module to a) Create a SimpleClinicalDocument instance and populate it with relevant administrative and medical information to form a tele medical report of a set of measurements, b) Use the provided DanishPHMRBuilder to generate a correctly...

  3. Burkina Faso - Social safety nets

    OpenAIRE

    World Bank

    2011-01-01

    Burkina Faso is a poor landlocked country with a narrow natural resource base and a rapidly expanding population of 15.8 million. This report, with the technical support of United Nations Children's Fund (UNICEF), provides a detailed, updated inventory of the existing social safety net programs and suggests policy measures that could improve their coverage, efficiency, relevance, and finan...

  4. Complexity Metrics for Workflow Nets

    DEFF Research Database (Denmark)

    Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.

    2009-01-01

    Process modeling languages such as EPCs, BPMN, flow charts, UML activity diagrams, Petri nets, etc.\\ are used to model business processes and to configure process-aware information systems. It is known that users have problems understanding these diagrams. In fact, even process engineers and system...

  5. Petri Nets in Cryptographic Protocols

    DEFF Research Database (Denmark)

    Crazzolara, Federico; Winskel, Glynn

    2001-01-01

    A process language for security protocols is presented together with a semantics in terms of sets of events. The denotation of process is a set of events, and as each event specifies a set of pre and postconditions, this denotation can be viewed as a Petri net. By means of an example we illustrate...

  6. Stomatal Conductance and Chlorophyll Characteristics and Their Relationship with Yield of Some Cocoa Clones Under Tectona grandis, Leucaena sp., and Cassia surattensis.

    Directory of Open Access Journals (Sweden)

    Fakhrusy Zakariyya

    2015-08-01

    Full Text Available An optimum physiological condition will support high yield and quality of cocoa production. The research was aimed to study the effects of stomatal conductance and chlorophyll content related to cocoa production under three shade regimes.This research was conducted in Kaliwining Experimental Station, elevation of 45 m above sea level with D climate type based on Schmidt & Fergusson. Cocoa trees which were planted in 1994 at a spacing of 3 X 3 m were used in the study planted by using split plot design. The shade tree species were teak (Tectona grandis, krete (Cassiasurattensis, and lamtoro (Leucaena sp. as the main plots, and cocoa clones of Sulawesi 01,Sulawesi 02, KKM 22 and KW 165 as sub plots. This study showed that there was interaction between cocoa clone and shade species for stomatal conductance where stomatal diffusive resistance of KKM 22 was the best under Leucaena sp.and Cassiasurattensis with the values of 1.38 and 1.34 s.cm -1, respectively. The highest chlorophyll content, stomatal index and transpiration values was under Leucaena sp. shade. There was positive correlation between chlorophyll content and transpiration with pod yield of cocoa. The highest yield and the lowest bean count wereobtainedon Sulawesi 01 clone under Leucaenasp. shade.Keywords: stomatal conductance, transpiration, diffusive resistance, shades trees, clones,pod yield

  7. Net Neutrality in Canada and what it means for libraries

    Directory of Open Access Journals (Sweden)

    Alex Guindon

    2010-06-01

    Full Text Available Net Neutrality, the idea that the Internet should be provided to all without discrimination based on content or applications, has been an important policy issue in the last few years. A lack of net neutrality could negatively impact libraries, intellectual freedom, cultural diversity, and the right to privacy. This paper looks at the issues that underline the net neutrality debate and describes how they are shaped by the different actors that are concerned with the future of the Internet. Technological issues, such as traffic shaping by Internet Service Providers, and legal issues in the context of Canada’s Telecommunications Act, are also addressed. Finally, the paper reviews the recent CRTC policy on Internet Traffic Management Practices.

  8. Electrical characteristics of chlorophyll-a polyvinyl alcohol photovoltaic cells

    Institute of Scientific and Technical Information of China (English)

    HAN, Yun-Yu(韩允雨); DIAO, Zhao-Yu*(刁兆玉); LI, Huai-Xiang(李怀祥); CHI, Yan-Hui(迟颜辉)

    2000-01-01

    A type of photovoltaic cell was made by sandwiching microcrystalline chlorophyll-a (chla) layer and polyvinyl alcohol (PVA) film between two semiconductive optical transparent SnO2 electrodes, such as SnO2/chla/PVA/SnO2. The cell showed a dark rectifying effect and presented photovaltaic properties on illumination, which was illustrated by the charge distribution in the cell. It was suggested that the SnO2/chla junction might be responsible for photovaltage and the chla/PVA for the charge separation upon irradiation of visible light. The equivalent electric circuit was discussed and its equivalent component values were calculated.

  9. Simple heterogeneity parametrization for sea surface temperature and chlorophyll

    Science.gov (United States)

    Skákala, Jozef; Smyth, Timothy J.

    2016-06-01

    Using satellite maps this paper offers a complex analysis of chlorophyll & SST heterogeneity in the shelf seas around the southwest of the UK. The heterogeneity scaling follows a simple power law and is consequently parametrized by two parameters. It is shown that in most cases these two parameters vary only relatively little with time. The paper offers a detailed comparison of field heterogeneity between different regions. How much heterogeneity is in each region preserved in the annual median data is also determined. The paper explicitly demonstrates how one can use these results to calculate representative measurement area for in situ networks.

  10. Probing of chlorophyll a with pulsed tunable laser

    International Nuclear Information System (INIS)

    Probing with a tunable pulsed dye laser of a solution of chlorophyll a in pyridine is reported. Transmission studies at fixed wavelengths as function of laser intensity reveal that various levels within the singlet and triplet system become populated and the life-time of these excited states is determined. Fluorescence in the blue part of the electromagnetic spectrum is recorded and the spectrum is induced as a result of the consecutive absorption of two red photons. Using time resolved spectroscopical detection methods, the fluorescence spectra of dimers, free from interference of that due to the monomer, are recorded. (orig.)

  11. Influence of water-based ferrofluid upon chlorophylls in cereals

    International Nuclear Information System (INIS)

    The present experimental investigation was focused on the study of the simultaneous influence of the water-based ferrofluid and static magnetic field exposure on young cereal plants. Water-based ferrofluid, stabilized with citric acid was added daily in various concentrations, ranging between 10 and 250 μL/L, in the culture medium of maize (Zea mays) plants in their early ontogenetic stages. The used static magnetic field was about 50 mT. In order to investigate the biochemical changes of chlorophylls and total carotenoids, spectrophotometric measurements were carried out, that revealed stimulatory effects of ferrofluid and magnetic exposure upon the studied plant species

  12. Phenoplant: a web resource for the exploration of large chlorophyll fluorescence image datasets

    OpenAIRE

    Rousseau, Céline; Hunault, Gilles; Gaillard, Sylvain; Bourbeillon, Julie; Montiel, Gregory; Simier, Philippe; Campion, Claire; Jacques, Marie Agnes; Belin, Etienne; Boureau, Tristan

    2015-01-01

    Background Image analysis is increasingly used in plant phenotyping. Among the various imaging techniques that can be used in plant phenotyping, chlorophyll fluorescence imaging allows imaging of the impact of biotic or abiotic stresses on leaves. Numerous chlorophyll fluorescence parameters may be measured or calculated, but only a few can produce a contrast in a given condition. Therefore, automated procedures that help screening chlorophyll fluorescence image datasets are needed, especiall...

  13. Bark and leaf chlorophyll fluorescence are linked to wood structural changes in Eucalyptus saligna

    OpenAIRE

    Johnstone, Denise; Tausz, Michael; Moore, Gregory; Nicolas, Marc

    2014-01-01

    Wood structure and wood anatomy are usually considered to be largely independent of the physiological processes that govern tree growth. This paper reports a statistical relationship between leaf and bark chlorophyll fluorescence and wood density. A relationship between leaf and bark chlorophyll fluorescence and the quantity of wood decay in a tree is also described. There was a statistically significant relationship between the leaf chlorophyll fluorescence parameter F v/F m and wood density...

  14. Experimental effects of sand-dust storm on tolerance index, percentage phototoxicity and chlorophyll a fluorescence of Vigna radiata L.

    Directory of Open Access Journals (Sweden)

    M. Alavi

    2015-03-01

    Full Text Available In arid and semi-arid parts of the world excessive mineral aerosol carried by air parcels is a common climatic incident with well-known environmental side effects. In this way, we studied the role of sand-dust accumulation on various aspects of productivity of Vigna radiata L. including dry mass (DM, chlorophyll (Chl a, b, Chlorophyll a fluorescence (effective quantum yield of PSII photochemistry (ФPSII, maximal quantum yield of PSII photochemistry (Fv/Fm and electron transport rate (ETR. V. radiata was exposed to a gradient of dust concentrations in a dust chamber (0.5 (T1, 1(T2 and 1.5 g/m3 (T3 simulated by a dust generator for a period of 60 days. Results of this experiment indicate that DM and Chl content of shoot are negatively correlated with the intensity of the dust exposure. Exposure of V. radiata to dust compared with the control was caused 5% (T1, 14% (T2 and 27% (T3 reduction in leaf DM (p≤0.05, ANOVA. Also, exposure to the dust induced a significant (p≤0.05 reduction in the Total Chl content in (T3 25%. Also, we showed that ФPSII, ETR and Fv/Fm were affected by increasing of the dust concentrations. Exposure to the dust resulted in a significant reduction in ETR of 15%, 22%, and 43%.

  15. Grasping at molecular interactions and genetic networks in Drosophila melanogaster using FlyNets, an Internet database.

    OpenAIRE

    Sanchez, C; Lachaize, C; Janody, F; Bellon, B; Röder, L; Euzenat, J.; Rechenmann, F; Jacq, B

    1999-01-01

    FlyNets (http://gifts.univ-mrs.fr/FlyNets/FlyNets_home_page.++ +html) is a WWW database describing molecular interactions (protein-DNA, protein-RNA and protein-protein) in the fly Drosophila melanogaster. It is composed of two parts, as follows. (i) FlyNets-base is a specialized database which focuses on molecular interactions involved in Drosophila development. The information content of FlyNets-base is distributed among several specific lines arranged according to a GenBank-like format and ...

  16. Chlorophyll bleaching by UV-irradiation in vitro and in situ: Absorption and fluorescence studies

    International Nuclear Information System (INIS)

    Chlorophyll bleaching by UV-irradiation has been studied by absorbance and fluorescence spectroscopy in extracts containing mixtures of photosynthetic pigments, in acetone and n-hexane solutions, and in aqueous thylakoid suspensions. Chlorophyll undergoes destruction (bleaching) accompanied by fluorescent transient formation obeying first-order kinetics. The bleaching is governed by UV-photon energy input, as well as by different chlorophyll molecular organizations in solvents of different polarities (in vitro), and in thylakoids (in situ). UV-C-induced bleaching of chlorophylls in thylakoids is probably caused by different mechanisms compared to UV-A- and UV-B-induced bleaching

  17. Ocean color spectral variability studies using solar-induced chlorophyll fluorescence

    Science.gov (United States)

    Hoge, Frank E.; Swift, Robert N.

    1987-01-01

    It is suggested that chlorophyll-induced ocean color spectral variability can be studied using only a passive airborne spectroradiometer instrument, with solar-induced chlorophyll fluorescence used as the standard against which all correlations are performed. The intraspectral correlation (ISC) method is demonstrated with results obtained during an airborne mapping mission in the New York Bight. The curvature algorithm is applied to the solar-induced chlorophyll fluorescence at about 690 nm, and good agreement is found with results obtained using active-passive correlation spectroscopy. The ISC method has application to spectral variability and resulting chlorophyll concentration measurement in different environmental conditions and in different water types.

  18. Chlorophyll as a simple, inexpensive and environment-friendly colorimetric indicator for NO2 gas

    Directory of Open Access Journals (Sweden)

    May Kristine O. Bernardo

    2014-06-01

    Full Text Available Chlorophyll is utilized as a simple, inexpensive and environment-friendly (“green” colorimetric indicator for nitrogen dioxide (NO2 gas. A drastic color change from green to yellow was observed when chlorophyll, either dissolved in CH2Cl2 solution or absorbed into paper, was exposed to NO2 gas. Other gases such as CO2 and SO2 did not exhibit any color change with chlorophyll. Spectroscopic analysis showed nitration of chlorophyll as possible cause for the color change.

  19. MES16, a member of the methylesterase protein family, specifically demethylates fluorescent chlorophyll catabolites during chlorophyll breakdown in Arabidopsis.

    Science.gov (United States)

    Christ, Bastien; Schelbert, Silvia; Aubry, Sylvain; Süssenbacher, Iris; Müller, Thomas; Kräutler, Bernhard; Hörtensteiner, Stefan

    2012-02-01

    During leaf senescence, chlorophyll (Chl) is broken down to nonfluorescent chlorophyll catabolites (NCCs). These arise from intermediary fluorescent chlorophyll catabolites (FCCs) by an acid-catalyzed isomerization inside the vacuole. The chemical structures of NCCs from Arabidopsis (Arabidopsis thaliana) indicate the presence of an enzyme activity that demethylates the C13(2)-carboxymethyl group present at the isocyclic ring of Chl. Here, we identified this activity as methylesterase family member 16 (MES16; At4g16690). During senescence, mes16 leaves exhibited a strong ultraviolet-excitable fluorescence, which resulted from large amounts of different FCCs accumulating in the mutants. As confirmed by mass spectrometry, these FCCs had an intact carboxymethyl group, which slowed down their isomerization to respective NCCs. Like a homologous protein cloned from radish (Raphanus sativus) and named pheophorbidase, MES16 catalyzed the demethylation of pheophorbide, an early intermediate of Chl breakdown, in vitro, but MES16 also demethylated an FCC. To determine the in vivo substrate of MES16, we analyzed pheophorbide a oxygenase1 (pao1), which is deficient in pheophorbide catabolism and accumulates pheophorbide in the chloroplast, and a mes16pao1 double mutant. In the pao1 background, we additionally mistargeted MES16 to the chloroplast. Normally, MES16 localizes to the cytosol, as shown by analysis of a MES16-green fluorescent protein fusion. Analysis of the accumulating pigments in these lines revealed that pheophorbide is only accessible for demethylation when MES16 is targeted to the chloroplast. Together, these data demonstrate that MES16 is an integral component of Chl breakdown in Arabidopsis and specifically demethylates Chl catabolites at the level of FCCs in the cytosol. PMID:22147518

  20. Plagiarism Detection using ROUGE and WordNet

    CERN Document Server

    Chen, Chien-Ying; Ke, Hao-Ren

    2010-01-01

    With the arrival of digital era and Internet, the lack of information control provides an incentive for people to freely use any content available to them. Plagiarism occurs when users fail to credit the original owner for the content referred to, and such behavior leads to violation of intellectual property. Two main approaches to plagiarism detection are fingerprinting and term occurrence; however, one common weakness shared by both approaches, especially fingerprinting, is the incapability to detect modified text plagiarism. This study proposes adoption of ROUGE and WordNet to plagiarism detection. The former includes ngram co-occurrence statistics, skip-bigram, and longest common subsequence (LCS), while the latter acts as a thesaurus and provides semantic information. N-gram co-occurrence statistics can detect verbatim copy and certain sentence modification, skip-bigram and LCS are immune from text modification such as simple addition or deletion of words, and WordNet may handle the problem of word subst...