Uptake of 14C-carbofuran from rice plants by brown planthopper (nilaparvata lugens stal) and green leafhopper (Nephotettix virencence)

International Nuclear Information System (INIS)

Sumatra, M.; Anwar, E.; Kuswadi, A.N.; Soekarna, D.

1988-01-01

An experiment was carried out to determine the amount of 14-C-carbofuran taken up by brown planthopper (BPH) and green leafhopper (GLH) from ride plants containing 14-C-carbofuran. The roots of 30 days old rice plants were immersed in Kimura B solution containing carbofuran (0.6ug/ml) with activity of 18600 pCi/ml. After 3 days, 20 BPH and 20 GLH released onto the rice stems and leaves. The mortalities of BPH and GLH were similar after 24 and 48 hours of the release. The average radioactivity found in living GLH was 3.5 times of those found in living GLH was 3.5 times of those found in living BPH. And in dead GLH was 3.2 times on those in dead BPH. Radioactivity in rice leaves was 3.5 times of those in stems. This layer chromatograph of extracts of Kimura B solution, stems, and leaves showed that small amounts of carbofuran had degraded to substances like 3-OH-carbofuran and 3-keto-carbofuran. The percentage of radioactivity found as carbofuran decreased with time, while the amount of 3-ket-carbofuran increased. (authors). 6 refs, 2 figs, 6 tab

Broader leaves result in better performance of indica rice under drought stress.

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Farooq, M; Kobayashi, N; Ito, O; Wahid, A; Serraj, R

2010-09-01

Leaf growth is one of the first physiological processes affected by changes in plant water status under drought. A decrease in leaf expansion rate usually precedes any reduction in stomatal conductance or photosynthesis. Changes in leaf size and stomatal opening are potential adaptive mechanisms, which may help avoid drought by reducing transpiration rate, and can be used to improve rice genotypes in water-saving cultivation. The indica rice cultivar IR64 and four of its near-isogenic lines (NILs; BC(3)-derived lines) unique for leaf size traits, YTK 124 (long leaves), YTK 127 (broad leaves), YTK 205 (short leaves) and YTK 214 (narrow leaves), were compared in this study for changes in leaf growth and its water status. The plants were subjected to two soil water regimes, well-watered and progressive soil drying measured by the fraction of transpirable soil water (FTSW). Applied drought reduced leaf number, total leaf area, specific leaf area, plant biomass, tiller number, plant height, stomatal conductance, amount of water transpired, leaf relative water content, and leaf water potential more in IR64 and the NILs than in the respective controls; nonetheless, transpiration efficiency (TE) was slightly higher under drought than in the well-watered controls. NILs with broader leaves had higher biomass (and its individual components), less stomatal conductance, and higher TE under drought than NILs with narrow and shorter leaves. Under drought, leaf number was positively correlated with tiller number and plant height; nonetheless, root weight and total biomass, water transpired and TE, and plant height and TE were positively correlated with each other. However, a negative correlation was observed between stomatal conductance and the FTSW threshold at which normalized transpiration started to decline during soil drying. Overall, the IR64-derived lines with broader leaves performed better than NILs with narrow and short leaves under drought. Copyright 2010 Elsevier Gmb

Alterations in growth, oxidative damage, and metal uptake of five aromatic rice cultivars under lead toxicity.

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Ashraf, Umair; Hussain, Saddam; Anjum, Shakeel Ahmad; Abbas, Farhat; Tanveer, Mohsin; Noor, Mehmood Ali; Tang, Xiangru

2017-06-01

Lead (Pb) affects plant growth and its related physio-biochemical functions negatively. The present study investigated the responses of five different fragrant rice cultivars viz., Meixiangzhan (MXZ-2), Xiangyaxiangzhan (XYXZ), Guixiangzhan (GXZ), Basmati-385 (B-385), and Nongxiang-18 (NX-18) to four different Pb concentrations viz., 0, 400, 800 and 1200 μM. Results depicted that Pb toxicity significantly (P rice plants; nonetheless, a significant variation was found in the sensitivity of rice cultivars to Pb toxicity. Soluble sugars increased significantly only at 1200 μM in GXZ and 800 μM in B-385, whilst the maximum reductions in protein contents were observed at 1200 μM Pb for all rice cultivars. Proline contents were reduced for XYXZ and NX-18 at Pb1200 μM. Activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) as well as reduced glutathione (GSH) and oxidized glutathione (GSSG) showed differential behavior among Pb treatments and rice cultivars. Among rice cultivars, GXZ showed better antioxidative defense system under Pb toxicity compared with all other cultivars. For all rice cultivars, the trend for Pb accumulation was recorded as: roots > stems > leaves. Furthermore, significant but negative correlations among Pb uptake and plant height (r = -0.79), tillers per plant (r = -0.91) and plant dry biomass (r = -0.81) were recorded for all rice cultivars whereas the values of translocation factor (TF) from stems to leaves were higher than roots to stems. In sum, Pb reduced the early growth and caused physio-biochemical changes in all rice cultivars, nonetheless, GXZ proved better able to tolerate Pb stress than all other rice cultivars under study. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Determination of plant species for the phytoremediation of carbofuran residue in rice field soils

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Alissara Reungsang

2005-09-01

Full Text Available This study searched for plant species suitable for accumulating carbofuran residue in rice field soil. Three groups of plant, i.e. grass crops, upland crops, and vegetable crops, were grown in 8 inches diameter plastic pots filled with soil containing 5 mg/kg carbofuran. Parts of plants (stems and leaves, roots, fruits were harvested at day 120 and analyzed for carbofuran residue using HPLC. The results indicated that Helianthus annuus L. (sunflower was the most suitable species for phytoremediation of carbofuran residue in rice field soil because it highly accumulated carbofuran up to 93.4 μg/kg dry weight in its stems and leaves. In addition, H. annuus L. (sunflower could tolerate carbofuran since it showed similar physical appearance (circumference and height to control not receiving carbofuran.

Effect of heavy metal stress on the catalase activity and expression of isozymes in the leaves of rice seedling

International Nuclear Information System (INIS)

Ge Cailin; Yang Xiaoyong; Zhu Hongxia; Wang Zegang; Luo Shishi; Ma Fei; Sun Jinhe

2002-01-01

The effect of heavy metal stress on the catalase (CAT) activity and expression of isozymes in the leaves of rice (Wuyujing, Yangdao 6, Shanyou 818) seedling was measured and analyzed. The results showed as follows. (1) When the concentration of Cu, Cd and Hg was in the range of 0.05-2.0 mM, the CAT activity decreased continuously with the concentration of Cu and Cd increasing. However, with the concentration of Hg increasing the CAT activity rapidly decreased first, and then increased slightly, and again decreased obviously, indicating that the Cu, Cd and Hg of 0.05-2.0 mM inhibited the CAT activity in the leaves of rice seedling. (2) The results by using polyacrylamide concentration gradient gel electrophoresis technique to analyze the CAT isozymes indicated that, on the normal condition, there were 1 to 2 CAT isozymes being expressed in the rice leaves (2 CAT isozymes being expressed in Wuyujing leaves, 1 CAT isozymes in Yangdao 6 and Shanyou 818 leaves). 0.1 mM Cd stress induced Wuyujing leaves to express 1 new CAT isozymes, 0.1 mM Cd and Hg stress also induced Yangdao 6 leaves to express 1 new CAT isozymes, but the expression of CAT isozymes, which were expressed in normal condition, were inhibited by Cu, Cd and Hg stress

Identification of Morphological Character and Esterase Isozyme Pattern in Second-Generation Black Rice Plant Irradiated to Gamma Rays

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Hartanti, R. S.; Putri, T. A. N.; Zulfa, F.; Sutarno; Suranto

2017-04-01

Black rice is one of the functional foods due to its high anthocyanin content. Black rice grain was irradiated by gamma rays with a dose of 200 Gy and 300 Gy. The main purpose of this irradiation is to induce mutation to the black rice plant in order to achieve the improved organism. This study was undertaken to elucidate the morphological character and esterase isozyme pattern of black rice plant after irradiated by gamma rays. There were morphological differences on leaves, stems and grains between irradiated and non irradiated black rice plant. Gamma radiation dose of 200 Gy showed the significant influence of the length of the stem, number of internodes, and length of leaves. The radiation dose of 300 Gy showed the significant influence of the decrease value of diameter of 3rd internodes, number of branches and width of leaves. Flowering time is getting faster as increasing radiation dose. At the age of 74 days after planting there are 9.15% plants of 200 Gy radiation dose that have flowered faster than normal plants. This value increased into 11.45% at the dose of radiation 300 Gy. There were differences in the esterase banding pattern between radiation dose of 200 Gy and 300 Gy than the control plants, indicated that randomly mutation has occurred.

The buffering capacity of stems: genetic architecture of nonstructural carbohydrates in cultivated Asian rice, Oryza sativa.

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Wang, Diane R; Han, Rongkui; Wolfrum, Edward J; McCouch, Susan R

2017-07-01

Harnessing stem carbohydrate dynamics in grasses offers an opportunity to help meet future demands for plant-based food, fiber and fuel production, but requires a greater understanding of the genetic controls that govern the synthesis, interconversion and transport of such energy reserves. We map out a blueprint of the genetic architecture of rice (Oryza sativa) stem nonstructural carbohydrates (NSC) at two critical developmental time-points using a subpopulation-specific genome-wide association approach on two diverse germplasm panels followed by quantitative trait loci (QTL) mapping in a biparental population. Overall, 26 QTL are identified; three are detected in multiple panels and are associated with starch-at-maturity, sucrose-at-maturity and NSC-at-heading. They tag OsHXK6 (rice hexokinase), ISA2 (rice isoamylase) and a tandem array of sugar transporters. This study provides the foundation for more in-depth molecular investigation to validate candidate genes underlying rice stem NSC and informs future comparative studies in other agronomically vital grass species. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Endophytic Colonization of Rice by a Diazotrophic Strain of Serratia marcescens

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Gyaneshwar, Prasad; James, Euan K.; Mathan, Natarajan; Reddy, Pallavolu M.; Reinhold-Hurek, Barbara; Ladha, Jagdish K.

2001-01-01

Six closely related N2-fixing bacterial strains were isolated from surface-sterilized roots and stems of four different rice varieties. The strains were identified as Serratia marcescens by 16S rRNA gene analysis. One strain, IRBG500, chosen for further analysis showed acetylene reduction activity (ARA) only when inoculated into media containing low levels of fixed nitrogen (yeast extract). Diazotrophy of IRBG500 was confirmed by measurement of 15N2 incorporation and by sequence analysis of the PCR-amplified fragment of nifH. To examine its interaction with rice, strain IRBG500 was marked with gusA fused to a constitutive promoter, and the marked strain was inoculated onto rice seedlings under axenic conditions. At 3 days after inoculation, the roots showed blue staining, which was most intense at the points of lateral root emergence and at the root tip. At 6 days, the blue precipitate also appeared in the leaves and stems. More detailed studies using light and transmission electron microscopy combined with immunogold labeling confirmed that IRBG500 was endophytically established within roots, stems, and leaves. Large numbers of bacteria were observed within intercellular spaces, senescing root cortical cells, aerenchyma, and xylem vessels. They were not observed within intact host cells. Inoculation of IRBG500 resulted in a significant increase in root length and root dry weight but not in total N content of rice variety IR72. The inoculated plants showed ARA, but only when external carbon (e.g., malate, succinate, or sucrose) was added to the rooting medium. PMID:11274124

Transfer of gaseous iodine from atmosphere to rough rice, brown rice and polished rice

International Nuclear Information System (INIS)

Sumiya, Misako; Uchida, Shigeo; Muramatsu, Yasuyuki; Ohmomo, Yoichiro; Yamaguchi, Shuho; Obata, Hitoshi.

1987-01-01

Experiments were carried out in order to obtain information required for establishing transfer coefficients of gaseous iodine (I 2 ) to rough rice, brown rice and polished rice. The gaseous iodine deposited on young rice plants before the heading period was scarcely found in the rough rice harvested at the full ripe stage. The biological half life of iodine in hull, however, was much slower than that in leaves of 14 days. The translocation of iodine from leaves and stalks to rough rice was not clearly recognized. Therefore, it was deduced that iodine found in brown rice mainly should originate from that deposited on the hull. The distribution ratios of iodine between rough rice and brown rice, and between brown rice and polished rice were 100:4 and 100:30 on 100 grains basis, respectively. If average normalized deposition velocity (V d(m) ) or derived deposition velocity (V s ) are given, the transfer coefficients of gaseous iodine to rough rice (TF r ), brown rice (TF b ) and polished rice (TF p ) could be calculated. (author)

Effects of Different Planting Times of Different Rice Cultivars on Control of the Striped Stem Borer (Chilo suppressalis (Lepidoptera: Pyralidae

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T. Oskou

2016-06-01

Full Text Available Introduction: Rice (Oryza sativa L. is one of the world’s most important staple food crops. In Asia, it is the main item of the diet of 3.5 billion people. Rice stem borers are common insect pests in many rice growing countries. Striped stem borer (Chilo suppressalis Walker, belonging to Lepidoptera and family of Pyralidae is the most important rice pest in the Northern Iran. Stem borer larva damages rice stem and disturbs nutrient translocation from root to leaf. As the result, tillers in vegetative stage died, which is called dead heart. When larva infests generative stage, it causes empty panicle, which is called white head. Integrated pest management (IPM practices for controlling the stem borers in Iran have not been fully implemented because of limited control technologies which are available. Farmers often rely on heavily insecticide application, although many insecticide applications are not effective. Therefore, many physical and cultural practices have been suggested, including adjustment of planting time to escape the plant from heavy pest. Materials and Methods: The study was conducted in deputy of rice research institute in Amol, Mazandaran, Iran, during 2011-2012. The experiment was arranged in split plot design with planting time as main plot and cultivar as subplot and was replicated three times. Three planting times tested were the first planting time i.e. 15 days before farmers’ planting time, the second planting time (simultaneously with farmers’ planting time, and the third planting time (15days after farmers’ planting time. Six rice cultivars tested, representing three types of rice cultivar, Tarom and Kohsar (early maturity cultivars, Shirodi and Fajr (medium maturity cultivars, Neda and Nemat (late maturity cultivar. Rice seedlings were transplanted at 25 cm planting distance in a 3 m x 9 m plot size. Weeding and fertilization were done as recommended. No insecticide was applied. Dead hearts and white heads were

Determination of critical nitrogen dilution curve based on stem dry matter in rice.

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Syed Tahir Ata-Ul-Karim

Full Text Available Plant analysis is a very promising diagnostic tool for assessment of crop nitrogen (N requirements in perspectives of cost effective and environment friendly agriculture. Diagnosing N nutritional status of rice crop through plant analysis will give insights into optimizing N requirements of future crops. The present study was aimed to develop a new methodology for determining the critical nitrogen (Nc dilution curve based on stem dry matter (SDM and to assess its suitability to estimate the level of N nutrition for rice (Oryza sativa L. in east China. Three field experiments with varied N rates (0-360 kg N ha(-1 using three Japonica rice hybrids, Lingxiangyou-18, Wuxiangjing-14 and Wuyunjing were conducted in Jiangsu province of east China. SDM and stem N concentration (SNC were determined during vegetative stage for growth analysis. A Nc dilution curve based on SDM was described by the equation (Nc = 2.17W(-0.27 with W being SDM in t ha(-1, when SDM ranged from 0.88 to 7.94 t ha(-1. However, for SDM < 0.88 t ha(-1, the constant critical value Nc = 1.76% SDM was applied. The curve was dually validated for N-limiting and non-N-limiting growth conditions. The N nutrition index (NNI and accumulated N deficit (Nand of stem ranged from 0.57 to 1.06 and 51.1 to -7.07 kg N ha(-1, respectively, during key growth stages under varied N rates in 2010 and 2011. The values of ΔN derived from either NNI or Nand could be used as references for N dressing management during rice growth. Our results demonstrated that the present curve well differentiated the conditions of limiting and non-limiting N nutrition in rice crop. The SDM based Nc dilution curve can be adopted as an alternate and novel approach for evaluating plant N status to support N fertilization decision during the vegetative growth of Japonica rice in east China.

Investigation of the profile of phenolic compounds in the leaves and stems of Pandiaka heudelotii using gas chromatography coupled with flame ionization detector.

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Ifeanacho, Mercy O; Ikewuchi, Catherine C; Ikewuchi, Jude C

2017-05-01

The profile of phenolic compounds in the leaves and stems of Pandiaka heudelotii was investigated using gas chromatography coupled with flame ionization detector. The leaves and stems had high flavonoids and benzoic acid derivatives content, and moderate levels of lignans and hydroxycinnamates. Twenty-eight known flavonoids were detected, which consisted mainly of kaempferol (41.93% in leaves and 47.97% in stems), (+)-catechin (17.12% in leaves and 16.11% in stems), quercetin (13.83% in leaves and 9.39% in stems), luteolin (7.34% in leaves and 7.71% in stems), and artemetin (6.53% in leaves and 4.83% in stems). Of the six known hydroxycinnamates detected, chlorogenic acid (80.79% in leaves and 87.56% in stems) and caffeic acid (18.98% in leaves and 12.30% in stems) were the most abundant, while arctigenin (77.81% in leaves and 83.40% in stems) and retusin (13.82% in leaves and 10.59% in stems) were the most abundant of the nine known lignans detected. Twelve known benzoic acid derivatives were detected, consisting mainly of ellagic acid (65.44% in leaves and 72.89% in stems), p-hydroxybenzoic acid (25.10% in leaves and 18.95% in stems), and vanillic acid (8.80% in leaves and 7.30% in stems). The rich phytochemical profile of the leaves and stems is an indication of their ability to serve as sources of nutraceuticals.

Rice stem borers in Malaya. A proposal to use mutation breeding for their control

Energy Technology Data Exchange (ETDEWEB)

Vohra, F C [University of Malaya, Kuala Lumpur (Malaysia)

1970-03-01

The problem of rice stem borers: Among the various problems in the rice crop the loss caused by the larvae of lepidopterous stem borers seems to be very serious. In some districts of the Kurian area, the rate of damage has been as much as 100%. It is not unlikely that the stem borer threat will become worse with the introduction of double cropping in many areas. The control of stem borers has mainly been through the application of various insecticides, namely DDT, BHC, Endrin, dieldrin and gamma-BHC, and this has met with a certain amount of success. The chemical method of control, however, is not fully satisfactory because of: (a) The high recurrent cost in application; (b) The danger of hazard to man by residues; (c) The toxic effects to fish and mammals in the paddy fields; (d) The poisoning of the natural parasites of the borers; (e) The difficulties for proper application, exact concentrations etc. by untrained farmers; and (f) The probability for development of insecticide resistance in stem borers. Apparently there is an urgent need for some control free from chemical hazards. Scientists in various countries have turned to breeding for varietal resistance, among other approaches, to save the crop from damage by stem borers. The development of a variety of rice resistant to stem borers will provide an effective control operative at all levels of insect population without additional cost and inconvenience to the farmer. The research project: To achieve this objective a research project has recently been started as a co-operative venture at the School of Biological Sciences, University of Malaya, Kuala Lumpur. This project involves (a) Detailed ecological studies of boxers in different varieties of rice grown commonly in the various parts of the country; (b) A study of parasites of borers for possible biological control; and (c) Production of rice varieties resistant to stem borers through induction of mutations and hybridization with locally used types

Photosynthetic Characteristics of Flag Leaves in Rice White Stripe Mutant 6001 During Senescence Process

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Xiao-hui ZHEN

2014-11-01

Full Text Available Physiological, biochemical and electron microscopy analyses were used to investigate the photosynthetic performance of flag leaves in rice white stripe mutant 6001 during the senescence process. Results showed that the chlorophyll content at the heading and milk-ripe stages in rice mutant 6001 were about 34.78% and 3.00% less than those in wild type 6028, respectively. However, the chlorophyll content at the fully-ripe stage in rice mutant 6001 was higher than that in wild type 6028. At the heading stage, the net photosynthetic rate (Pn in rice mutant 6001 was lower than that in wild type 6028. Rice mutant 6001 also exhibited a significantly slower decrease rate of Pn than wild type 6028 during the senescence progress, especially at the later stage. Furthermore, Ca2+-ATPase, Mg2+-ATPase and photophosphorylation activities exhibited the similar trends as the Pn. During the senescence process, the 68 kDa polypeptide concentrations in the thylakoid membrane proteins exhibited a significant change, which was one of the critical factors that contributed to the observed change in photosynthesis. We also observed that the chloroplasts of rice mutant 6001 exhibited higher integrity than those of wild type 6028, and the chloroplast membrane of rice mutant 6001 disintegrated more slow during the senescence process. In general, rice mutant 6001 had a relatively slower senescence rate than wild type 6028, and exhibited anti-senescence properties.

Investigating and modeling the pyrolysis kinetic of leaves and stems of pistachio trees for biofuel production

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M Ostad Hoseini

2016-09-01

Full Text Available Introduction The lignocelluloses materials have high potential for producing various types of biofuels. These materials include various parts of plants, especially leaves and stems that are left without a specific usage after annual pruning. These residues can be used through slow or fast pyrolysis process for production of liquid and gaseous biofuels. The slow pyrolysis is taking place at temperatures below 500°C while fast pyrolysis process takes place at a temperature above 700°C. Various studies on production of biofuels from plant residues have shown that the temperature, heating rate and the resident time of pyrolysis process are the main factors that affect the final product quality. At present time, in Iran, there are more than 360 thousands hectares of pistachio growing fields which annually produce over 215 thousands metric tons residues which are mainly leaves and stems. The main objective of this study was to measure the heating properties of the powders prepared from the leaves and the stem of pistachio trees. These properties include higher heating value (HHV, lower heating value (LHV and thermal gravimetric analysis (TGA of the powders. Then the powders were separately pyrolysed and the kinetic of the pyrolysis process for producing charcoal from them was investigated. Materials and Methods In this research, leaves and stems of pistachio trees were initially analyzed to determine their chemical constituents including moisture content, volatile compounds, carbon (C, hydrogen (H, nitrogen (N, sulfur (S and oxygen (O content. Using these constituents the height heating value and low heating value for the leaves and the stems were determined. The thermal gravimetric analysis (TGA of the powders was made to select a proper heating temperature for pyrolysis of the powders. In each experiment about 10 g of powder powders were pyrolyzed to produce char. Based on TGA results, the pyrolysis experiments were performed at 350, 400, 450 and

Effects of Soil Veterinary Antibiotics Pollution on Rice Growth

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XU Qiu-tong

2016-01-01

Full Text Available To understand the potential effect of soil veterinary antibiotics pollution on the growth of rice, a main food crop in China, oxytetracycline which was used widely in livestock and poultry breeding was selected to test the effects of different levels of soil antibiotics pollution on growth and yield of rice plant at both seedling and growth periods. Relationship between oxytetracycline accumulated in different organs of rice plant and oxytetracycline pollution levels in the soil was characterized. The results showed that the effects of soil oxytetracycline pollution on rice growth mainly occurred at the seedling stage, and the effect on the underground part was obviously greater than the above-ground part of rice. Significant negative effects on biomass of the underground part of rice, root activity, and chlorophyll content and oxidase activity of the leave at the seedling stage were found when soil oxytetracycline pollution concentrations was over 30 mg·kg-1. The consequence from the impact of soil oxytetracycline pollution on rice seedling could be extended to the whole growth period of the plant, which could reduce the number of tiller and rice yield. Oxytetracycline accumulated in various organs of rice plant was in the sequence of root> leaf> stem> grain. Rice roots had low capacity to uptake oxytetracycline from the soil, the transfer capacity of oxytetracycline from the roots to leaf, stem, and grain was also weak. Considering the low oxytetracycline pollution levels in most of current actual farmland soils (less than 10 mg·kg-1 and lower accumulation character of oxytetracycline in the grain, it is thought that the direct damage of soil oxytetracycline pollution on rice production is small.

Deposition velocity of gaseous organic iodine from the atmosphere to rice plants

International Nuclear Information System (INIS)

Muramatsu, Yasuyuki; Shigeo-Uchida; Sumiya, Misako; Ohmomo, Yoichiro

1996-01-01

To obtain parameter values for the assessment of 129 I transfer from the atmosphere to rice, deposition of CH 3 I to rice plants has been studied. The mass normalized deposition velocity (V D ) of CH 3 I for rough (unhulled) rice was 0.00048 cm 3 g -1 s -1 , which is about 1/300 of that of I 2 . Translocation of iodine, deposited as CH 3 I on leaves and stems, to rice grain was negligibly small. Distribution of iodine between hull and inner part of the grain was found to depend also on the chemical forms of atmospheric iodine to be deposited. The ratio of the iodine distribution in a grain exposed to CH 3 I was as follows: rough rice: brown rice (hulled rice):polished rice = 1.0:0.49:0.38. The distribution ratio in polished grains for CH 3 I exposed rice was about 20 times higher than that for I 2 . 22 refs., 1 fig., 6 tabs

Estimation of genetic divergence in rice (oryza sativa l) germplasms on the basis of paddy yield and rice stem borer's (pyralidae: lepidoptera) resistance

International Nuclear Information System (INIS)

Sarwar, M.

2013-01-01

Field trials were carried out to estimate resistance along with paddy yield in 55 rice germplasm lines (35 aromatic and 20 non-aromatic genotypes) for rice stem borers (Pyralidae: Lepidoptera) to expose their potential in pest management approach. The results expressed significant differences for pest damage build-up and paddy yield among the rice germplasm lines. The findings clearly portrayed that based upon the percentage of pest invasions (dead hearts and white heads damage), no genotype was exclusively resistant to stem borers damage under field conditions. Two aromatic genotypes, Jajai-15A/97 and Basmati-Cr-34, exhibited least borers prevalence and amplified paddy yield while Sonehri Sugdasi (P) and Sada Gulab (P) pointed out a peak pest invasion and declined paddy yield. The estimation of pest incidence build-up and paddy productivity within non-aromatic genotypes confirmed that IR8 (P), IR6-15-2 and IR6 (P) were mainly proficient for bearing condensed pest invasion and augmented paddy yield. IR8-2.5-4, IR6-15-10 and IR6-20-9 demonstrated elevated pest susceptibility and gave poor yield. Rest of the germplasms appeared to be least tolerant or vulnerable to pest build-up and reduced paddy production. The tolerant and high yielding genotypes should be popularised in rice borers endemic areas and can be used in varietals resistance breeding strategy. The outcome of current studies necessitates the integration of existing host plant tolerance along with other management strategies to accomplish a suitable control of rice stem borers and enhance paddy yield. (author)

Influence of fertilization on the capability of rice resistance to diseases

Science.gov (United States)

Hu, Xue-Feng; Chang, Yue-Ya; Jiang, Ying; Yan, Xiao-Juan; Luo, Fan

2013-04-01

Organic cultivation of rice requires no use of any agricultural chemicals during the entire period of growth, and so the rice's self-prevention of diseases and pests is vitally important. A field experiment was carried out to study the possible influence of different fertilization on the capability of rice resistance to diseases and pests. A rice variety used for this experiment is Jia-He 218. Four treatments (A, B, C and D) were designed: A is a control, without using any fertilizers; B, after manuring of green azolla, 0.67 kg/m2; C, after manuring of rapeseed cake, 0.30 kg/m2; D, after fertilizing of ammonium bicarbonate, 0.025 kg/m2, and urea, 0.025 kg/m2. The experiment plot is 66.7 m2, with three replicates. The results indicated that the fertilization patterns significantly influence the growth of rice seedlings: The heights by A, B, C and D are 37 cm, 40 cm , 42 cm and 45 cm on average, respectively; the spike numbers, 45, 65, 73 and 75, respectively; chlorophyll contents in leaves, 1.84 mg/g, 2.42 mg/g, 3.02 mg/g and 3.97 mg/g, respectively. The rice with the different fertilization also varies in nutrient concentration in leaves: NH4-N concentration in leaves by A, B, C and D is 47.5 mg/kg, 61.1 mg/kg, 74.7 mg/kg and 135.8 mg/kg on average, respectively; NO3-N in leaves, 138.9 mg/kg, 185.2 mg/kg, 154.3 mg/kg and 293.2 mg/kg, respectively. The fertilization patterns, moreover, show a significant influence on the incidence of diseases and pests to rice seedlings: The incidence of rice cnaphalocrocis medinalis by A, B, C and D is 1.33 %, 1.50 %, 1.75 % and 89.0 % on average, respectively; that of bacterial leaf blight, 0, 1.25 %, 1.75 % and 85.0 %, respectively; number of rice planthopper in each plant, 20, 21, 21 and 30, respectively. As a result, the yield of rice grain by A, B, C and D is 4540 kg/ha, 4606 kg/ha, 4503 kg/ha and 4092 kg/ha on average, respectively. In conclusion, the rice seedlings treated with chemical fertilizers grow large and tender

Fungal colonization and decomposition of leaves and stems of Salix arctica on deglaciated moraines in high-Arctic Canada

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Osono, Takashi; Matsuoka, Shunsuke; Hirose, Dai; Uchida, Masaki; Kanda, Hiroshi

2014-06-01

Fungal colonization, succession, and decomposition of leaves and stems of Salix arctica were studied to estimate the roles of fungi in the decomposition processes in the high Arctic. The samples were collected from five moraines with different periods of development since deglaciation to investigate the effects of ecosystem development on the decomposition processes during the primary succession. The total hyphal lengths and the length of darkly pigmented hyphae increased during decomposition of leaves and stems and were not varied with the moraines. Four fungal morphotaxa were frequently isolated from both leaves and stems. The frequencies of occurrence of two morphotaxa varied with the decay class of leaves and/or stems. The hyphal lengths and the frequencies of occurrence of fungal morphotaxa were positively or negatively correlated with the contents of organic chemical components and nutrients in leaves and stems, suggesting the roles of fungi in chemical changes in the field. Pure culture decomposition tests demonstrated that the fungal morphotaxa were cellulose decomposers. Our results suggest that fungi took part in the chemical changes in decomposing leaves and stems even under the harsh environment of the high Arctic.

Interaction between Pyricularia oryzae, four Helminthosporium species and Curvularia lunata in rice leaves

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M. Bahous

2003-08-01

Full Text Available The interaction between six fungal parasites of rice: Pyricularia oryzae, Helminthosporium oryzae, H. sativum, H. spiciferum, H. australiensis and Curvularia lunata was studied quantitatively by a modified plant ecology technique known as the de Wit replacement series. Each fungus was inoculated alone or in combination with one of the other five fungi in various proportions into rice plants under experimental conditions. Leaves developing lesions were harvested and incubated in a moist chamber. The yield of each fungus was its conidial production on the rice leaves. The artificial inoculations indicated that interactions between the pathogens in the mixture could be beneficial, antagonistic, or null. Interspecific interaction (i.e. antagonism occurred in the majority of paired combinations (H. oryzae + P. oryzae; H. sativum + H. spiciferum, H. australiensis, C. lunata or P. oryzae; H. australiensis + H. spiciferum, C. lunata or P. oryzae; and P. oryzae + C. lunata. The relative yield total (RYT lines were significantly lower than the expected value, which is 1. The RYT lines were concave upward, revealing a beneficial effect of one or both pathogens on the other, when H. oryzae was in mixture with H. sativum or H. spiciferum. A null effect between fungi occurred in four combinations (H. oryzae + H. australiensis or C. lunata; H. spiciferum + C. lunata; and P. oryzae + H. spiciferum showing that with these combinations inter- and intraspecific competitions were equal in intensity. Thus, the de Wit replacement series technique indicated that it was possible to quantify the interaction between all the pathogenic fungi tested.

Comparative proteomics of leaves found at different stem positions of maize seedlings.

Science.gov (United States)

Chen, Yi-Bo; Wang, Dan; Ge, Xuan-Liang; Zhao, Biligen-Gaowa; Wang, Xu-Chu; Wang, Bai-Chen

2016-07-01

To better understand the roles of leaves at different stem positions during plant development, we measured the physiological properties of leaves 1-4 on maize seedling stems, and performed a proteomics study to investigate the differences in protein expression in the four leaves using two-dimensional difference gel electrophoresis and tandem mass spectrometry in conjunction with database searching. A total of 167 significantly differentially expressed protein spots were found and identified. Of these, 35% are involved in photosynthesis. By further analysis of the data, we speculated that in leaf 1 the seedling has started to transition from a heterotroph to an autotroph, development of leaf 2 is the time at which the seedling fully transitions from a heterotroph to an autotroph, and leaf maturity was reached only with fully expanded leaves 3 and 4, although there were still some protein expression differences in the two leaves. These results suggest that the different leaves make different contributions to maize seedling growth via modulation of the expression of the photosynthetic proteins. Together, these results provide insight into the roles of the different maize leaves as the plant develops from a heterotroph to an autotroph. Copyright © 2016 Elsevier GmbH. All rights reserved.

Distribution of assimilates derived from canopy leaves at different milky stage of intergeneric high-yielding hybrid rice

International Nuclear Information System (INIS)

Tang Jianjun

1997-01-01

Distribution characteristics of assimilates derived from 14 C-glucose fed on different canopy leaves of the high-yielding intergeneric hybrid rice Yuanyou 1 and GER-1, intra-varietal 3-line hybrid rice Shanyou 63, maternal and paternal parents of intergeneric hybrid rice at various ripening stage from flowering stage to late milky stage were studied with pot experiments under greenhouse in 1993 and 1994 in Guangzhou. The results indicates that there exists a significant difference in exportation of radioactivity from the leaf fed, partitioning of radioactivity exported into different organs and importation accumulation percent of total radioactivity in the rice panicle Yuanyou 1 has a high average exportation percent, importation accumulation percent and a stable and sustainable grain-filling process, which results in a high seed-setting rate with large spikelet population

Soil-to-plant transfer factors of trace and major elements in rice plant (Oryza Sativa) at Kalpakkam

International Nuclear Information System (INIS)

Sreedevi, K.R.; Rajaram, S.; Thulasi Brindha, J.; Venkataraman, S.; Hegde, A.G.

2011-01-01

The objective of this study was to evaluate the distribution of trace and major elements in rice plant (Oryza Sativa) which is the staple diet of the public at Kalpakkam. The transfer factor from soil to various parts of plant was also studied. Trace and major elements such as Fe, Mn, Zn, Co, Cu, Ni, Cr, Cd, Pb , Sr, K, Ca and Mg were selected based on their role in nutrition and also to study the behaviour of their radioactive counterparts. Among the trace elements Fe concentration was observed to be maximum in soil, the mean value of which was 18394 mg/kg dry wt. Cadmium concentration was observed to be minimum with the mean value of 2 mg/kg dry wt. The maximum and minimum concentration observed in the rice grain were due to Zn and Cd and the values were found to be 9 and 0.044 mg/kg dry wt, respectively. In the stem and leaves part the maximum and minimum concentration was due to Fe and Cd and the values were found to be 26.8 and 0.12 mg/kg dry wt. Similarly in the root part Fe and Cd concentrations were found to be maximum and minimum, respectively. Among the different parts of the rice plant, trace elements concentration in root was maximum and in stem and leaves major elements concentration was maximum. Transfer factor from soil to plant parts was computed. In general, the transfer factor was maximum in root, followed by stem and leaves and grain for trace elements. The transfer factor computed for whole rice plant was maximum for Zn and minimum for Sr which is a significant observation from radiological point of view. (author)

Transcriptional profile of genes involved in ascorbate glutathione cycle in senescing leaves for an early senescence leaf (esl) rice mutant.

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Li, Zhaowei; Su, Da; Lei, Bingting; Wang, Fubiao; Geng, Wei; Pan, Gang; Cheng, Fangmin

2015-03-15

To clarify the complex relationship between ascorbate-glutathione (AsA-GSH) cycle and H2O2-induced leaf senescence, the genotype-dependent difference in some senescence-related physiological parameters and the transcript levels and the temporal patterns of genes involved in the AsA-GSH cycle during leaf senescence were investigated using two rice genotypes, namely, the early senescence leaf (esl) mutant and its wild type. Meanwhile, the triggering effect of exogenous H2O2 on the expression of OsAPX genes was examined using detached leaves. The results showed that the esl mutant had higher H2O2 level than its wild type at the initial stage of leaf senescence. At transcriptional level, the association of expression of various genes involved in the AsA-GSH cycle with leaf senescence was isoform dependent. For OsAPXs, the transcripts of two cytosolic OsAPX genes (OsAPX1 and OsAPX2), thylakoid-bound OsAPX8, chloroplastic OsAPX7 and peroxisomal OsAPX4 exhibited remarkable genotype-dependent variation in their expression levels and temporal patterns during leaf senescence, there were significantly increasing transcripts of OsAXP1 and OsAPX7, severely repressed transcripts of OsAPX4 and OsAPX8 for the esl rice at the initial leaf senescence. In contrast, the repressing transcript of OsAPX8 was highly sensitive to the increasing H2O2 level in the senescing rice leaves, while higher H2O2 concentration resulted in the enhancing transcripts of two cytosolic OsAPX genes, OsAPX7 transcript was greatly variable with different H2O2 concentrations and incubating duration, suggesting that the different OsAPXs isoforms played a complementary role in perceiving and scavenging H2O2 accumulation at various H2O2 concentrations during leaf senescence. Higher H2O2 level, increased AsA level, higher activities of APX and glutathione reductase (GR), and relatively stable GSH content during the entire sampling period in the leaves of esl mutant implied that a close interrelationship existed

Ethanol extracts of Newbouldia laevis stem and leaves modulate ...

African Journals Online (AJOL)

The ethanol extracts of N. laevis leaves and stem possessed antioxidant activity as shown by increased activities of superoxide dismutase and catalase, and glutathione levels of the diabetic rats after treatment. High levels of alkaline phosphatase (ALP), and alanine aminotransaminase (ALT), which are typical of oxidative ...

Genomic DNA sequence and cytosine methylation changes of adult rice leaves after seeds space flight

Science.gov (United States)

Shi, Jinming

In this study, cytosine methylation on CCGG site and genomic DNA sequence changes of adult leaves of rice after seeds space flight were detected by methylation-sensitive amplification polymorphism (MSAP) and Amplified fragment length polymorphism (AFLP) technique respectively. Rice seeds were planted in the trial field after 4 days space flight on the shenzhou-6 Spaceship of China. Adult leaves of space-treated rice including 8 plants chosen randomly and 2 plants with phenotypic mutation were used for AFLP and MSAP analysis. Polymorphism of both DNA sequence and cytosine methylation were detected. For MSAP analysis, the average polymorphic frequency of the on-ground controls, space-treated plants and mutants are 1.3%, 3.1% and 11% respectively. For AFLP analysis, the average polymorphic frequencies are 1.4%, 2.9%and 8%respectively. Total 27 and 22 polymorphic fragments were cloned sequenced from MSAP and AFLP analysis respectively. Nine of the 27 fragments from MSAP analysis show homology to coding sequence. For the 22 polymorphic fragments from AFLP analysis, no one shows homology to mRNA sequence and eight fragments show homology to repeat region or retrotransposon sequence. These results suggest that although both genomic DNA sequence and cytosine methylation status can be effected by space flight, the genomic region homology to the fragments from genome DNA and cytosine methylation analysis were different.

Labelling of rice seedlings and rice plants with 32P

International Nuclear Information System (INIS)

Achmad Nasroh, K.

1989-01-01

Labelling of rice seedlings and rice plants with 32 P. Labelled rice seedlings can be used to tag insect pests that feed on. Radioactivity counting of 32 P in the endosperm and in the shoot of rice seeds that soaked for 72 hours in KH 2 32 PO 4 solution of 1 μCi/ml were 29,300 and 9,500 cpm respectively. When these labelled seedlings were grown in unlabelled medium the radioactivity in the shoot increased. It was due to the 32 P that was translocated to the shoot from the endosperm. The 32 P translocation reached maximum about one week after the seedling were grown in the unlabelled medium. Labelled seedlings could also be produced by growing 5, 10 and 15 days old seedlings hydroponically in Kimura B solution containing 32 P. Ten days after growing, the radioactivity concentration of the seedlings stem reached about 115,000; 85,000 and 170,000 cpm/mg dry weight for the 5, 10 and 15 days old seedlings respectively. For the implementation of this method, 20 ml labelled Kimura B was needed for labelling of one seedling. The seedlings should be prepared in tap water. During the growth the 32 P in the labelled seedlings was distributed throughout the plant, so that new leaves and tillers became also radioactive. (author). 5 refs

A technique system for the measurement, reconstruction and character extraction of rice plant architecture.

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Xumeng Li

Full Text Available This study developed a technique system for the measurement, reconstruction, and trait extraction of rice canopy architectures, which have challenged functional-structural plant modeling for decades and have become the foundation of the design of ideo-plant architectures. The system uses the location-separation-measurement method (LSMM for the collection of data on the canopy architecture and the analytic geometry method for the reconstruction and visualization of the three-dimensional (3D digital architecture of the rice plant. It also uses the virtual clipping method for extracting the key traits of the canopy architecture such as the leaf area, inclination, and azimuth distribution in spatial coordinates. To establish the technique system, we developed (i simple tools to measure the spatial position of the stem axis and azimuth of the leaf midrib and to capture images of tillers and leaves; (ii computer software programs for extracting data on stem diameter, leaf nodes, and leaf midrib curves from the tiller images and data on leaf length, width, and shape from the leaf images; (iii a database of digital architectures that stores the measured data and facilitates the reconstruction of the 3D visual architecture and the extraction of architectural traits; and (iv computation algorithms for virtual clipping to stratify the rice canopy, to extend the stratified surface from the horizontal plane to a general curved surface (including a cylindrical surface, and to implement in silico. Each component of the technique system was quantitatively validated and visually compared to images, and the sensitivity of the virtual clipping algorithms was analyzed. This technique is inexpensive and accurate and provides high throughput for the measurement, reconstruction, and trait extraction of rice canopy architectures. The technique provides a more practical method of data collection to serve functional-structural plant models of rice and for the

Response of oxidative stress defense systems in rice (Oryza sativa) leaves with supplemental UV-B radiation

International Nuclear Information System (INIS)

Dai, Q.; Yan, B.; Huang, S.; Liu, X.; Peng, S.; Miranda, M.L.L.; Chavez, A.Q.; Vergara, B.S.; Olszyk, D.M.

1997-01-01

The impact of elevated ultraviolet-B radiation (UV-B, 280–320 nm) on membrane systems and lipid peroxidation, and possible involvement of active oxygen radicals was investigated in leaves of two UV-B susceptible rice cultivars (Oryza sativa L. cvs IR74 and Dular). Rice seedlings were grown in a greenhouse for 10 days and then treated with biologically effective UV-B (UV-B BE ) radiation for 28 days. Oxidative stress effects were evaluated by measuring superoxide anion (O 2 ) generation rate, hydrogen peroxide (H 2 O 2 ) content, malondialdehyde (MDA) concentration and relative electrolyte conductivity (EC) for IR74 and Dular at 0 (control), 6 or 13 kJ m −2 day −1 UV-B BE . Significant increases in these parameters were found in rice plants grown at 13 vs 0 kJ m −2 day −1 UV-B BE after 28 days; indicating that disruption of membrane systems may be an eventual reason for UV-B-induced injury in rice plants. There was a positive correlation between O 2 − generation and increases in EC or MDA in leaves. Activities of enzymatic and nonenzymatic free radical scavengers were measured for IR74 after 7, 14, 21 and 28 days of exposure to 13 or 0 UV-B BE to evaluate dynamics of these responses over time. Activities of catalase and superoxide dismutase (but not ascorbate peroxidase) and concentrations of ascorbic acid and glutathione were enhanced by 13 vs 0 UV-B BE after 14 days of UV-B exposure. Further exposure to 28 days of UV-B was associated with a decline in enzyme activities and ascorbic acid, but not glutathione. It is suggested that UV-B-induced injury may be associated with disturbance of active oxygen metabolism through the destruction and alteration of both enzymatic and nonenzymatic defense systems in rice. (author)

New target for rice lodging resistance and its effect in a typhoon.

Science.gov (United States)

Ishimaru, Ken; Togawa, Eiji; Ookawa, Taiichro; Kashiwagi, Takayuki; Madoka, Yuka; Hirotsu, Naoki

2008-02-01

We demonstrated the new target for lodging resistance in rice (Oryza sativa L.) by the analysis of physiological function of a locus for lodging resistance in a typhoon (lrt5) with the near isogenic line under rice "Koshihikari" genetic background (tentatively named S1). The higher lodging resistance of S1 was observed during a typhoon in September 2004 (28 days after heading), when most other plants in "Koshihikari" became lodged. Visual observations showed that bending of the upper stems triggered lodging during the typhoon; the upper stem of "Koshihikari" buckled completely, whereas that of S1 remained straight. In addition to the strong rain and winds during the typhoon, the weight of the buckled upper plant parts increased the pressure on adjacent plants and caused a domino effect in "Koshihikari". Young's modulus, an indicator of the rigidity of the culm, was significantly higher in S1 than in "Koshihikari". In the upper culm, the starch content in S1 was 4.8 times the value in "Koshihikari", and senescence was delayed in the upper leaves of S1. These results suggest that the rigidity of the upper culm by the higher starch content (as a result of delayed senescence in the upper leaves) may be responsible for the higher lodging resistance during a typhoon in rice.

Hybrid Sequencing of Full-Length cDNA Transcripts of Stems and Leaves in Dendrobium officinale

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Liu He

2017-10-01

Full Text Available Dendrobium officinale is an extremely valuable orchid used in traditional Chinese medicine, so sought after that it has a higher market value than gold. Although the expression profiles of some genes involved in the polysaccharide synthesis have previously been investigated, little research has been carried out on their alternatively spliced isoforms in D. officinale. In addition, information regarding the translocation of sugars from leaves to stems in D. officinale also remains limited. We analyzed the polysaccharide content of D. officinale leaves and stems, and completed in-depth transcriptome sequencing of these two diverse tissue types using second-generation sequencing (SGS and single-molecule real-time (SMRT sequencing technology. The results of this study yielded a digital inventory of gene and mRNA isoform expressions. A comparative analysis of both transcriptomes uncovered a total of 1414 differentially expressed genes, including 844 that were up-regulated and 570 that were down-regulated in stems. Of these genes, one sugars will eventually be exported transporter (SWEET and one sucrose transporter (SUT are expressed to a greater extent in D. officinale stems than in leaves. Two glycosyltransferase (GT and four cellulose synthase (Ces genes undergo a distinct degree of alternative splicing. In the stems, the content of polysaccharides is twice as much as that in the leaves. The differentially expressed GT and transcription factor (TF genes will be the focus of further study. The genes DoSWEET4 and DoSUT1 are significantly expressed in the stem, and are likely to be involved in sugar loading in the phloem.

Study on residues of 14C-Fenitrothion in a model rice-fish ecosystem and in a field rice-fish ecosystem

International Nuclear Information System (INIS)

Zhang Zhongliang; Wang Huaxin; Guo Dazhi; Chen Zhiyu; Wu Suchueng

1993-01-01

Residues of 14 C-fenitrothion in a model rice-fish ecosystem and field rice-fish ecosystem were studied. When equal amounts of the pesticide were applied, the extractable residues in brown rice (equivalent to 34.3±1.9 μg/kg fenitrothion) and rice stems and leaves (20.9±1.5 μg/kg) of the model rice-fish ecosystem were 10-15 times higher than that of the field rice-fish ecosystem (4.48±0.13 μg/kg and 1.27±0.34 μg/kg respectively). Residues in upper part of the soil (6.50±0.1--8.10±0.2 μg/kg) and lower part of the soil (1.30±0.1--1.50±0.1 μg/kg) of the model rice-fish ecosystem were 10-40 times higher than that of the field rice-fish ecosystem (0.17±0.01 μg/kg). The extractable residues in paddy water of the model ecosystem (0.30 ± 0.01 μg/kg) were similar to that of the field ecosystem (0.20±0.02 μg/kg). When the fenitrothion was sprayed on the rice plants, residues in brown rice, fish body, soil and paddy water were lower than those when the pesticide was spread on the surface of the soil. (author). 4 refs, 2 tabs

Reduced arsenic accumulation in indica rice (Oryza sativa L.) cultivar with ferromanganese oxide impregnated biochar composites amendments.

Science.gov (United States)

Lin, Lina; Gao, Minling; Qiu, Weiwen; Wang, Di; Huang, Qing; Song, Zhengguo

2017-12-01

The effects of biochar (BC) and ferromanganese oxide biochar composites (FMBC 1 and FMBC 2 ) on As (Arsenic) accumulation in rice were determined using a pot experiment. Treatments with BC or FMBC improved the dry weights of rice roots, stems, leaves, and grains in soils containing different As contamination levels. Compared to BC treatment, FMBC treatments significantly reduced As accumulation in different parts of the rice plants (P rice can be attributed to As(III) to As(V) oxidation by ferro - manganese binary oxide, which increased the As adsorbed by FMBC. Furthermore, Fe and Mn plaques on the rice root surface decreased the transport of As in rice. Taken together, our results demonstrated the applicability of FMBC as a potential measure for reducing As accumulation in rice, improving the amino acid content of rice grains, and effectively remediating As-polluted soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of net photosynthetic rate and 14C distribution between different cultural conditions on double cropping rice

International Nuclear Information System (INIS)

Huang Jianliang; Li Hesong; Zou Yingbin; Tu Naimei; Li Jianhui

2002-01-01

By applying the cultural method 'Vigorous Root-Strong Stem-Heavy Panicle Cultural Method' (VSHM), the yield of double cropping rice reached 18000 kg/hm 2 in large area at Liling county, Hunan province. The net photosynthetic rate and 14 C distribution of rice leaves between VSHM and traditional cultural methods (CK) were compared. The photosynthetic rate of the flag leaves at ripening stages under VSHM was higher than that of controls with both earlier rice or later rice. Regarding the net amount of 14 C-assimilate by a single flag leaf and the second top leaf, there were differences at the significant level of 0.01 and 0.05, respectively between VSHM and controls, and VSHM were 7.72%-35.05% higher. The percentage of distribution at panicles of 14 C-assimilate were 51.93%-61.40% when flag leaf was labelled, and 45.34%-54.25% when the second top leaf was labelled, that of earlier rice was higher than later rice respectively, but the differences were not significant between VSHM and CK. The actual yield of double cropping rice under the cultural condition of VSHM was 17710 kg/hm 2 , and increased by 18.33% when compared with controls

Rice microstructure

Science.gov (United States)

An understanding of plant structure is desirable to obtain a clear idea of the overall impact of a crop. A mature rice plant consists of leafy components (left in the field post-harvest) and paddy rice (collected). The rice plant is supported by a hollow stem (culm) with leaf sheaths attached to nod...

Quantitative Variation of Flavonoids and Diterpenes in Leaves and Stems of Cistus ladanifer L. at Different Ages

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Cristina Valares Masa

2016-02-01

Full Text Available The compounds derived from secondary metabolism in plants perform a variety of ecological functions, providing the plant with resistance to biotic and abiotic factors. The basal levels of these metabolites for each organ, tissue or cell type depend on the development stage of the plant and they may be modified as a response to biotic and/or abiotic stress. As a consequence, the resistance state of a plant may vary in space and time. The secondary metabolites of Cistus ladanifer have been quantified in leaves and stems throughout autumn, winter, spring and summer, and at different ages of the plant. This study shows that there are significant differences between young leaves, mature leaves and stems, and between individuals of different ages. Young leaves show significantly greater synthesis of flavonoids and diterpenes than mature leaves and stems, with a clear seasonal variation, and the differences between leaves at different growth stages and stems is maintained during the quantified seasons. With respect to age, specimens under one year of age secreted significantly lower amounts of compounds. The variation in the composition of secondary metabolites between different parts of the plant, the season and the variations in age may determine the interactions of Cistus ladanifer with the biotic and abiotic factors to which it is exposed.

Antimicrobial Activity of Extracts from Leaves, Stems and Flowers of Euphorbia macroclada against plant pathogenic fungi

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K. Al-Mughrabi

2003-12-01

Full Text Available Extracts drawn from dried and powdered flowers, stems and leaves of Euphorbia macroclada with some organic solvents were tested for antimicrobial effect against the fungi Verticillium dahliae, Fusarium oxysporum, Rhizopus stolonifer, Penicillium italicum, Rhizoctonia solani, Alternaria solani, Stemphylium solani, Cladosporium sp., Mucor sp., and Pythium sp. The strongest inhibitory effect of the extracts was observed against R. solani, V. dahliae, F. oxysporum, Pythium sp. and R. stolonifer. The weakest effect was against A. solani. Extracts from the stems had a stronger inhibitory effect than those from the flowers or leaves. Butanol was the best solvent to extract antimicrobial compounds from leaves, stems and flowers and was superior to chloroform, water and petroleum ether. Results clearly indicate that E. macroclada is a promising source of antimicrobial compounds.

Oxidative stress-triggered interactions between the succinyl- and acetyl-proteomes of rice leaves.

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Zhou, Heng; Finkemeier, Iris; Guan, Wenxue; Tossounian, Maria-Armineh; Wei, Bo; Young, David; Huang, Jingjing; Messens, Joris; Yang, Xibin; Zhu, Jun; Wilson, Michael H; Shen, Wenbiao; Xie, Yanjie; Foyer, Christine H

2018-05-01

Protein lysine acylations, such as succinylation and acetylation, are important post-translational modification (PTM) mechanisms, with key roles in cellular regulation. Antibody-based affinity enrichment, high-resolution liquid chromatography mass spectrometry analysis, and integrated bioinformatics analysis were used to characterize the lysine succinylome (K suc ) and acetylome (K ace ) of rice leaves. In total, 2,593 succinylated and 1,024 acetylated proteins were identified, of which 723 were simultaneously acetylated and succinylated. Proteins involved in photosynthetic carbon metabolism such as the large and small subunits of RuBisCO, ribosomal functions, and other key processes were subject to both PTMs. Preliminary insights into oxidant-induced changes to the rice acetylome and succinylome were gained from treatments with hydrogen peroxide. Exposure to oxidative stress did not regulate global changes in the rice acetylome or succinylome but rather led to modifications on a specific subset of the identified sites. De-succinylation of recombinant catalase (CATA) and glutathione S-transferase (OsGSTU6) altered the activities of these enzymes showing that this PTM may have a regulatory function. These findings not only greatly extend the list of acetylated and/or succinylated proteins but they also demonstrate the close cooperation between these PTMs in leaf proteins with key metabolic functions. © 2017 John Wiley & Sons Ltd.

Accumulation and distribution of polycyclic aromatic hydrocarbons in rice (Oryza sativa)

International Nuclear Information System (INIS)

Tao, S.; Jiao, X.C.; Chen, S.H.; Liu, W.X.; Coveney, R.M.; Zhu, L.Z.; Luo, Y.M.

2006-01-01

Various tissues of rice plants were sampled from a PAH contaminated site in Tianjin, China at different growth stages of the ripening period and analyzed for PAHs. PAHs were much higher in roots than in the exposed tissues. Grains and internodes accumulated much smaller amounts of PAHs than leaves, hulls or ear axes. No specific gradient trends along roots, stem, ear axes, and grains were observed, suggesting that systematic translocation among them is unlikely. Over the ripening period, PAH concentrations were increased in rice roots and decreased in most above-ground tissues. Significant correlations between PAH and lipid contents can only be observed during full mature stage. The spectra of individual PAH compounds in rice organs including roots were similar to those in air, rather than those in soil. There was also a significant correlation between bioconcentration factor (BCF, plant over air) and octanol/air partitioning coefficient (K oa ). - PAHs in various tissues of rice plants from various growth stages were investigated

Essential oils and crude extracts from Chrysanthemum trifurcatum leaves, stems and roots: chemical composition and antibacterial activity.

Science.gov (United States)

Sassi, Ahlem Ben; Skhiri, Fethia Harzallah; Chraief, Imed; Bourgougnon, Nathalie; Hammami, Mohamed; Aouni, Mahjoub

2014-01-01

The essential oils from the leaves, stems and roots of Chrysanthemum trifurcatum (Desf.) Batt. and Trab. var. macrocephalum (viv.) were obtained by hydrodistillation and their chemical compositions were analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), in order to get insight into similarities and differences as to their active composition. A total of fifty compounds were identified, constituting 97.84%, 99.02% and 98.20% of total oil composition of the leaves, stems and roots, respectively. Monoterpene hydrocarbons were shown to be the main group of constituents of the leaves and stems parts in the ratio of 67.88% and 51.29%, respectively. But, the major group in the roots oil was found to be sesquiterpene hydrocarbons (70.30%). The main compounds in leaves oil were limonene (26.83%), γ-terpinene (19.68%), α-pinene (9.7%) and α-terpenyl acetate (7.16%). The stems oil, contains mainly limonene (32.91%), 4-terpenyl acetate (16.33%) and γ-terpinene (5.93%), whereas the main compounds in roots oil were α-calacorene (25.98%), α-cedrene (16.55%), β-bourbobene (14.91%), elemol (7.45%) and 2-hexenal (6.88%). The crude organic extracts of leaves, stems and roots, obtained by maceration with solvents of increasing polarity: petroleum ether, ethyl acetate and methanol, contained tannins, flavonoids and alkaloids. Meanwhile, essential oils and organic extracts were tested for antibacterial activities against eight Gram-positive and Gram-negative strains, using a microdilution method. The oil and methanolic extact from C. trifurcatum leaves showed a great potential of antibacterial effect against Bacillus subtilis and Staphylococcus epidermidis, with an IC50 range of 31.25-62.5 µg/ml.

Comparative analgesic activity of the root bark, stem bark, leaves ...

African Journals Online (AJOL)

The analgesic activity of the water extracts (50,100 and150 mg/Kg body weight) of the root bark, stem bark, leaves, fruits and seeds of Carissa edulis were evaluated in mice using the mechanical method (tail-chip method) and chemical method (acetic acid induced writhing). The plant was found to have analgesic activity, ...

[Comparison on polysaccharide content and PMP-HPLC fingerprints of polysaccharide in stems and leaves of Dendrobium officinale].

Science.gov (United States)

Zhou, Gui-Fen; Pang, Min-Xia; Chen, Su-Hong; Lv, Gui-Yuan; Yan, Mei-Qiu

2014-03-01

In order to provide scientific basics for exploitation and sufficient application of Dendrobium officinale leaves resources, the phenol-sulfuric acid method was applied to determine the polysaccharide content. The monosaccharides were derivated by PMP and the derivatives were identified by HPLC-DAD-ESI-MS(n) and the contents of mannose and glucose were determined simultaneously. Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004A) was employed to generate the mean chromatogram and similarity analysis of the samples was carried out. The results demonstrated that polysaccharide content, monosaccharide compositions and composition ratio had an obvious difference between stems and leaves. The polysaccharide content of stems was higher than that of leaves. Monosaccharide composition in leaf was significantly different from that in stem. The polysaccharide from stems was composed of mannose and glucose, however the polysaccharide of leaves was acid heteropolysaccharide and was mainly composed of five monosaccharides, including mannose, galacturonic acid, glucose, galactose and arabinose. The similarity value of the 14 batches was above 0.9, indicating that similarity of fingerprints among different samples was high. The study can provide evidence for expanding the medicinal parts of D. officinale.

The mechanism of improved aeration due to gas films on leaves of submerged rice.

Science.gov (United States)

Verboven, Pieter; Pedersen, Ole; Ho, Quang Tri; Nicolai, Bart M; Colmer, Timothy D

2014-10-01

Some terrestrial wetland plants, such as rice, have super-hydrophobic leaf surfaces which retain a gas film when submerged. O2 movement through the diffusive boundary layer (DBL) of floodwater, gas film and stomata into leaf mesophyll was explored by means of a reaction-diffusion model that was solved in a three-dimensional leaf anatomy model. The anatomy and dark respiration of leaves of rice (Oryza sativa L.) were measured and used to compute O2 fluxes and partial pressure of O2 (pO2 ) in the DBL, gas film and leaf when submerged. The effects of floodwater pO2 , DBL thickness, cuticle permeability, presence of gas film and stomatal opening were explored. Under O2 -limiting conditions of the bulk water (pO2  gas film significantly increases the O2 flux into submerged leaves regardless of whether stomata are fully or partly open. With a gas film, tissue pO2 substantially increases, even for the slightest stomatal opening, but not when stomata are completely closed. The effect of gas films increases with decreasing cuticle permeability. O2 flux and tissue pO2 decrease with increasing DBL thickness. The present modelling analysis provides a mechanistic understanding of how leaf gas films facilitate O2 entry into submerged plants. © 2014 John Wiley & Sons Ltd.

Why (and how) they decide to leave: A grounded theory analysis of STEM attrition at a large public research university

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Minutello, Michael F.

A grounded theory investigation of STEM attrition was conducted that describes and explains why undergraduates at a large Mid-Atlantic research university decided to leave their initial STEM majors to pursue non-STEM courses of study. Participants ultimately decided to leave their initial STEM majors because they were able to locate preferable non-STEM courses of study that did not present the same kinds of obstacles they had encountered in their original STEM majors. Grounded theory data analysis revealed participants initially enrolled in STEM majors with tenuous motivation that did not withstand the various obstacles that were present in introductory STEM coursework. Obstacles that acted as demotivating influences and prompted participants to locate alternative academic pathways include the following: (1.) disengaging curricula; (2.) competitive culture; (3.) disappointing grades; (4.) demanding time commitments; and (5.) unappealing career options. Once discouraged from continuing along their initial STEM pathways, participants then employed various strategies to discover suitable non-STEM majors that would allow them to realize their intrinsic interests and extrinsic goals. Participants were largely satisfied with their decisions to leave STEM and have achieved measures of personal satisfaction and professional success.

Assessment of the medicinal potentials of the methanol extracts of the leaves and stems of Buddleja saligna.

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Adedapo, Adeolu A; Jimoh, Florence O; Koduru, Srinivas; Masika, Patrick J; Afolayan, Anthony J

2009-07-06

Buddleja saligna Willd (Loganiaceae) is a small to medium-sized evergreen tree; trunk short, often gnarled and crooked; crown dense, rounded or domed-shaped; foliage greyish green. The wild olives are traditionally used to lower blood pressures in many parts of the world. In southern Africa, bark and leaf decoctions are used to treat colic, coughs, colds, sore eyes, urinary problems and as purgatives. The antibacterial, antioxidant activities and phenolic contents of the methanol extracts of the leaves and stems of Buddleja saligna were evaluated using in vitro standard methods. Spectrophotometry was the basis for the determinations of total phenol, total flavonoids, flavonols, and proanthocyanidins. Tannins, quercetin and catechin equivalents were used for these parameters. The antioxidant activities of the leaves and stem extracts of Buddleja saligna were determined by ABTS, DPPH, and ferrous reducing antioxidant property (FRAP) methods. Laboratory isolates of 10 bacteria species which included five Gram-positive and five Gram-negative strains were used to assay for antibacterial activity of this plant. The antioxidant activities of the leaves as determined by the ABTS and DPPH were similar to that of the stem. The flavonoids and the flavonols contents of the leaves were higher than that of the stem but the total phenols, proanthocyanidins and FRAP activities were higher in the methanol extracts of the stem. The extracts did show activity against both Gram-positive and Gram-negative bacteria. For instance, while the methanol extract of the leaves showed good activities on all the organisms except Serratia marcescens and Pseudomonas aeruginosa at MICs of between 2.5 and 5.0 mg/ml, the extract of the stem only showed activities on Bacillus cereus, Streptococcus pyrogens and Pseudomonas aeruginosa at the same concentration. The results from this study indicate that the leaves and stem extracts of Buddleja saligna possess antioxidant properties and could serve as

Assessment of the medicinal potentials of the methanol extracts of the leaves and stems of Buddleja saligna

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Masika Patrick J

2009-07-01

Full Text Available Abstract Background Buddleja saligna Willd (Loganiaceae is a small to medium-sized evergreen tree; trunk short, often gnarled and crooked; crown dense, rounded or domed-shaped; foliage greyish green. The wild olives are traditionally used to lower blood pressures in many parts of the world. In southern Africa, bark and leaf decoctions are used to treat colic, coughs, colds, sore eyes, urinary problems and as purgatives. Methods The antibacterial, antioxidant activities and phenolic contents of the methanol extracts of the leaves and stems of Buddleja saligna were evaluated using in vitro standard methods. Spectrophotometry was the basis for the determinations of total phenol, total flavonoids, flavonols, and proanthocyanidins. Tannins, quercetin and catechin equivalents were used for these parameters. The antioxidant activities of the leaves and stem extracts of Buddleja saligna were determined by ABTS, DPPH, and ferrous reducing antioxidant property (FRAP methods. Laboratory isolates of 10 bacteria species which included five Gram-positive and five Gram-negative strains were used to assay for antibacterial activity of this plant. Results The antioxidant activities of the leaves as determined by the ABTS and DPPH were similar to that of the stem. The flavonoids and the flavonols contents of the leaves were higher than that of the stem but the total phenols, proanthocyanidins and FRAP activities were higher in the methanol extracts of the stem. The extracts did show activity against both Gram-positive and Gram-negative bacteria. For instance, while the methanol extract of the leaves showed good activities on all the organisms except Serratia marcescens and Pseudomonas aeruginosa at MICs of between 2.5 and 5.0 mg/ml, the extract of the stem only showed activities on Bacillus cereus, Streptococcus pyrogens and Pseudomonas aeruginosa at the same concentration. Conclusion The results from this study indicate that the leaves and stem extracts of

Comparison of phenotyping methods for resistance to stem rot and aggregated sheath spot in rice

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Stem and sheath diseases caused by Sclerotium oryzae Cattaneo (SCL) and Rhizoctonia oryzae-sativae Sawada Mordue (ROS) can severely reduce rice (Oryza sativa L.) yield and grain quality. Genetic resistance is the best strategy to control them. Phenotypic selection for resistance is hampered due to a...

Tolerance of different rice genotypes (oryza sativa l.) against the infestation of rice stem borers under natural field conditions

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Sarwar, M.; Ahmad, N.; Nasrullah; Tofique, M.

2010-01-01

The present studies report the genotypic responses of 61 rice (Oryza sativa L.) genotypes (35 aromatic and 26 non aromatic) against the infestation of rice stem borers under natural field conditions. The data obtained on these genotypes on larval infestation in combination with yield were the criteria to assess the resistance depicted by them. The studies showed that among aromatic genotypes, 'Khushboo-95' gave the best yield of grain and harboured the least pest infestation (2.81% dead hearts and 1.85% white heads); on the other hand variety 'Sonahri Sugdasi (P)' harboured the highest borers attack (10.37% and 19.30%) and yielded the lowest grain yield. Regarding non-aromatic genotypes, IR8-2.5-11 received least infestation (1.32% and 0.26% dead hearts and white heads, respectively) generating highest yield showing its tolerance to borer's attack, in contrast, genotype IR6-252 harboured the highest infestation (5.65%, 4.28%) and yielded minimum grain indicating its susceptibility. These results demonstrate the expression of resistance gene in the genome of tolerant rice genotypes that can provide season-long protection from the natural infestation of insect pests. (author)

Anti-inflammatory, antiallodynic effects and quantitative analysis of gallic acid in spray dried powders from Phyllanthus niruri leaves, stems, roots and whole plant

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Angélica G. Couto

2012-11-01

Full Text Available The anti-inflammatory and antiallodynic effects of spray dried powders starting from leaves, stems, roots, the mixture of leaves and stems, as well as the whole plant aqueous solutions of Phyllanthus niruri L., Phyllanthaceae, were assessed. Gallic acid, used as chemical marker, was quantified by HPLC in the spray dried powders. Carrageenan-induced inflammatory and allodynic responses in the mouse paw were used as pharmacological models. Quantitative and qualitative differences among chemical composition of different herb parts were observed. The oral administration of leaves or leaves plus stems spray dried powders (100 mg/kg significantly inhibited the carrageenan-induced allodynic effect (42±5 and 54±3%, respectively. Additionally, the spray dried powders of leaves significantly reduced carrageenan-induced paw oedema (35±6%. The spray dried powders of roots, stems, or the mixture of leaves, stems and roots (100 mg/kg, p.o. did not exhibit antiallodynic or antioedematogenic effect in the same model. In conclusion, differences in the chemical composition of spray dried powders from P. niruri are reflected in their in vivo pharmacological actions. Despite of a direct relationship of anti-inflammatory and antiallodynic effects with the gallic acid content had been observed, especially in the spray dried powders of leaves, the use of spray dried powders of leaves plus stems showed to be more effective, suggesting a synergic effect between their constituents.

Anti-inflammatory, antiallodynic effects and quantitative analysis of gallic acid in spray dried powders from Phyllanthus niruri leaves, stems, roots and whole plant

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Angélica G. Couto

2013-02-01

Full Text Available The anti-inflammatory and antiallodynic effects of spray dried powders starting from leaves, stems, roots, the mixture of leaves and stems, as well as the whole plant aqueous solutions of Phyllanthus niruri L., Phyllanthaceae, were assessed. Gallic acid, used as chemical marker, was quantified by HPLC in the spray dried powders. Carrageenan-induced inflammatory and allodynic responses in the mouse paw were used as pharmacological models. Quantitative and qualitative differences among chemical composition of different herb parts were observed. The oral administration of leaves or leaves plus stems spray dried powders (100 mg/kg significantly inhibited the carrageenan-induced allodynic effect (42±5 and 54±3%, respectively. Additionally, the spray dried powders of leaves significantly reduced carrageenan-induced paw oedema (35±6%. The spray dried powders of roots, stems, or the mixture of leaves, stems and roots (100 mg/kg, p.o. did not exhibit antiallodynic or antioedematogenic effect in the same model. In conclusion, differences in the chemical composition of spray dried powders from P. niruri are reflected in their in vivo pharmacological actions. Despite of a direct relationship of anti-inflammatory and antiallodynic effects with the gallic acid content had been observed, especially in the spray dried powders of leaves, the use of spray dried powders of leaves plus stems showed to be more effective, suggesting a synergic effect between their constituents.

Research Advances in High-Yielding Cultivation and Physiology of Super Rice

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Jing FU

2012-09-01

Full Text Available In 1996, China launched a program to breed super rice or super hybrid rice by combining intersubspecific heterosis with ideal plant types. Today, approximately 80 super rice varieties have been released and some of them show high grain yields of 12–21 t/hm2 in field experiments. The main reasons for the high yields of super rice varieties, compared with those of conventional varieties, can be summarized as follows: more spikelets per panicle and larger sink size (number of spikelets per square meter; larger leaf area index, longer duration of green leaf, greater photosynthetic rate, higher lodging resistance, greater dry matter accumulation before the heading stage, greater remobilization of pre-stored carbohydrates from stems and leaves to grains during the grain-filling period; and larger root system and greater root activity. However, there are two main problems in super rice production: poor grain-filling of the later-flowering inferior spikelets (in contrast to earlier-flowering superior spikelets, and low and unstable seed-setting rate. Here, we review recent research advances in the crop physiology of super rice, focusing on biological features, formation of yield components, and population quality. Finally, we suggest further research on crop physiology of super rice.

Physiological and Biochemical Characteristics in Flag Leaves of the C Liangyou Series of Hybrid Rice Combinations at Late Growth Stages

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Wen-bang TANG

2010-12-01

Full Text Available The contents of chlorophyll, soluble sugars, soluble proteins and thiobarbituric acid reaction substance (TBARS, chlorophyll fluorescence parameters, net photosynthetic rate as well as the activities of superoxide dismutase (SOD and peroxidase (POD of flag leaves at the late growth stages were studied by using C Liangyou series of hybrid rice combinitions as material and Shanyou 63 as control. The C Liangyou series of hybrid rice combinations used in the experiment included C Liangyou 396, C Liangyou 87, C Liangyou 755 and C Liangyou 34, which all used C815S as male sterile line. The contents of chlorophyll, soluble sugars and soluble proteins in flag leaves of the C Liangyou series combinations at the late growth stages were higher than those of the control, whereas the TBARS content was lower than that of the control. The activities of SOD and POD were significantly higher than those of the control on the 7th day after heading, and then decreased slowly. FPSII value and qP value of flag leaves decreased at the late growth stages, and these two parameters in flag leaves of the C Liangyou series combinations were higher than those of the control, while the qN value increased at the late growth stages and was lower than that of the control. The net photosynthetic rate of flag leaves at the late growth stage was higher compared with the control. These results suggest that slow senescence and strong photosynthetic capability in flag leaves at the late growth stages are the physiological basis of the C Liangyou series combinations.

Biogeographical patterns of biomass allocation in leaves, stems, and roots in China's forests.

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Zhang, Hao; Wang, Kelin; Xu, Xianli; Song, Tongqing; Xu, Yanfang; Zeng, Fuping

2015-11-03

To test whether there are general patterns in biomass partitioning in relation to environmental variation when stand biomass is considered, we investigated biomass allocation in leaves, stems, and roots in China's forests using both the national forest inventory data (2004-2008) and our field measurements (2011-2012). Distribution patterns of leaf, stem, and root biomass showed significantly different trends according to latitude, longitude, and altitude, and were positively and significantly correlated with stand age and mean annual precipitation. Trade-offs among leaves, stems, and roots varied with forest type and origin and were mainly explained by stand biomass. Based on the constraints of stand biomass, biomass allocation was also influenced by forest type, origin, stand age, stand density, mean annual temperature, precipitation, and maximum temperature in the growing season. Therefore, after stand biomass was accounted for, the residual variation in biomass allocation could be partially explained by stand characteristics and environmental factors, which may aid in quantifying carbon cycling in forest ecosystems and assessing the impacts of climate change on forest carbon dynamics in China.

Characterization of the complete mitochondrial genome of Chilo auricilius and comparison with three other rice stem borers.

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Cao, Shuang-Shuang; Du, Yu-Zhou

2014-09-15

The mitogenome of Chilo auricilius (Lepidoptera: Pyraloidea: Crambidae) was a circular molecule made up of 15,367 bp. Sesamia inferens, Chilo suppressalis, Tryporyza incertulas, and C. auricilius, are closely related, well known rice stem borers that are widely distributed in the main rice-growing regions of China. The gene order and orientation of all four stem borers were similar to that of other insect mitogenomes. Among the four stem borers, all AT contents were below 83%, while all AT contents of tRNA genes were above 80%. The genomes were compact, with only 121-257 bp of non-coding intergenic spacer. There are 56 or 62-bp overlapping nucleotides in Crambidae moths, but were only 25-bp overlapping nucleotides in the noctuid moth S. inferens. There was a conserved motif 'ATACTAAA' between trnS2 (UCN) and nad1 in Crambidae moths, but this same region was 'ATCATA' in the noctuid S. inferens. And there was a 6-bp motif 'ATGATAA' of overlapping nucleotides, which was conserved in Lepidoptera, and a 14-bp motif 'TAAGCTATTTAAAT' conserved in the three Crambidae moths (C. suppressalis, C. auricilius and T. incertulas), but not in the noctuid. Finally, there were no stem-and-loop structures in the two Chilo moths. Copyright © 2014 Elsevier B.V. All rights reserved.

Mutation direction by irradiation in rice

International Nuclear Information System (INIS)

Wang Cailian; Chen Qiufang; Jin Wei; Lu Yimei

2001-01-01

The mutation directions of rice were studied. The results indicated that the mutation directions of rice induced by 14 C were invert correlation to their genetic backgrounds of tested rice varieties, i.e. early mature and short stem varieties produced later mature and higher stem mutation; late mature and high stem varieties produced earlier mature and shorter stem mutation; the varieties of middle maturity and height produced both direction mutations of earlier and later maturity or shorter and higher stem. The mutation directions induced by 14 C were also related to treated doses and stages. Frequency of earlier maturity mutation by protons treatment were higher than those induced by other mutagens. Frequency of later maturity by γ-rays were higher than those induced by other mutagens. Frequency of short stem mutation by synchronous irradiation (soft X-rays) were higher than those induced by other mutagens. Frequency of beneficial mutation induced by proton treatment were higher than those induced by γ-rays

Total flavonoid content and antioxidant activity in leaves and stems extract of cultivated and wild tabat barito (Ficus deltoidea Jack)

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Manurung, Hetty; Kustiawan, Wawan; Kusuma, Irawan W.; Marjenah

2017-02-01

Tabat barito (Ficus deltoidea Jack) is a name given by Dayak Tribe who lived in Borneo-Kalimantan and it is belongs to the moraceae. Almost all of the parts of F. deltoidea plant is widely used as a medicinal property. The total flavonoid content (TFC) and antioxidant activity from cultivated and wild F. deltoidea leaves and stems extract were assessed. Total flavonoid content was estimated by using Aluminium chloride colorimetric method and expressed as catechin equivalents (mg CE g-1 extract) and the antioxidant activity by the DPPH (2,2-diphenyl-1-picryl hydrazyl) method. The content of total flavonoid of leaves and stems (430.77 and 371.80 µg CE mg-1 extract) of cultivated F. deltoidea were higher than in the wild leaves and stems (114.82 and 66.67 µg CE mg-1 extract). The IC50 of leaves extract of cultivated and wild F. deltoidea, based on the DPPH assay, has a strong antioxidant activity (34.19 and 39.31 µg mL-1 extract) as compared to stems extract. These results showed that the cultivated F. deltoidea are suitable source for medicinal properties and the leaves could be exploited as source of natural antioxidants.

CMYB1 Encoding a MYB Transcriptional Activator Is Involved in Abiotic Stress and Circadian Rhythm in Rice

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Min Duan

2014-01-01

Full Text Available Through analysis of cold-induced transcriptome, a novel gene encoding a putative MYB transcription factor was isolated and designated Cold induced MYB 1 (CMYB1. Tissue-specific gene expression analysis revealed that CMYB1 was highly expressed in rice stems and nodes. qRT-PCR assay indicated that CMYB1 was dramatically induced by cold stress (>100-folds and induced by exogenous ABA and osmotic stress. Interestingly, CMYB1 showed rhythmic expression profile in rice leaves at different developmental stages. Subcellular localization assay suggested that CMYB1-GFP (green fluorescent protein fusion protein was localized in the nuclei. Moreover, CMYB1 exhibited the transcriptional activation activity when transiently expressed in rice protoplast cells. Taken together, CMYB1 probably functions as a transcriptional activator in mediating stress and rhythm responsive gene expression in rice.

Chemical composition and anti-inflammatory evaluation of essential oils from leaves and stem barks from Drimys brasiliensis Miers (Winteraceae)

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Lago, Joao Henrique G.; Carvalho, Larissa A.C.; Silva, Flavia S. da; Romoff, Paulete; Toyama, Daniela de O.; Favero, Oriana A.

2010-01-01

The essential oils from leaves and stem barks from Drimys brasiliensis Miers (Winteraceae) were individually obtained by hydrodistillation and their compounds characterized by use of GC/FID and GC/MS. The main identified derivatives were monoterpenes (leaves 4.31% and stem barks 90.02%) and sesquiterpenes (leaves 52.31% and stem barks 6.35%). Additionally, the sesquiterpene polygodial was isolated from hexane extract from stem barks of D. brasiliensis after chromatographic steps and characterized by spectroscopic means, mainly NMR. Aiming the evaluation of anti-inflammatory potential, the crude essential oils and the sesquiterpene polygodial were subjected to bioassays to evaluate the acute toxicity of these compounds as well as the anti-inflammatory and antinociceptive activities induced by carrageenan and formalin in mice. Ours results showed that essential oil obtained from the stem barks significantly reduced the oedema induced by carrageenan. The anti-inflammatory effect induced by stem barks oil (at 200 mg kg -1 ) was similar to observed for indomethacin (at 10 mg kg -1 ) and superior for polygodial (at 200 mg kg -1 ) in 30 and 60 min after the administration of essential oils. The inflammatory response induced by formalin was effective to the stem barks oil (62.5%) in comparison to polygodial (50.0%). (author)

Chemical composition and anti-inflammatory evaluation of essential oils from leaves and stem barks from Drimys brasiliensis Miers (Winteraceae)

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Lago, Joao Henrique G., E-mail: joao.lago@unifesp.b [Universidade Federal de Sao Paulo (UNIFESP-EPM), Diadema, SP (Brazil). Dept. de Ciencias Exatas e da Terra; Carvalho, Larissa A.C.; Silva, Flavia S. da; Romoff, Paulete [Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil). Centro de Ciencias e Humanidades; Toyama, Daniela de O.; Favero, Oriana A. [Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil). Centro de Ciencias Biologicas e da Saude

2010-07-01

The essential oils from leaves and stem barks from Drimys brasiliensis Miers (Winteraceae) were individually obtained by hydrodistillation and their compounds characterized by use of GC/FID and GC/MS. The main identified derivatives were monoterpenes (leaves 4.31% and stem barks 90.02%) and sesquiterpenes (leaves 52.31% and stem barks 6.35%). Additionally, the sesquiterpene polygodial was isolated from hexane extract from stem barks of D. brasiliensis after chromatographic steps and characterized by spectroscopic means, mainly NMR. Aiming the evaluation of anti-inflammatory potential, the crude essential oils and the sesquiterpene polygodial were subjected to bioassays to evaluate the acute toxicity of these compounds as well as the anti-inflammatory and antinociceptive activities induced by carrageenan and formalin in mice. Ours results showed that essential oil obtained from the stem barks significantly reduced the oedema induced by carrageenan. The anti-inflammatory effect induced by stem barks oil (at 200 mg kg{sup -1}) was similar to observed for indomethacin (at 10 mg kg{sup -1}) and superior for polygodial (at 200 mg kg{sup -1}) in 30 and 60 min after the administration of essential oils. The inflammatory response induced by formalin was effective to the stem barks oil (62.5%) in comparison to polygodial (50.0%). (author)

Mutant-inducing effect of γ-ray irradiation for hybrid rice F1 derived from cross of black glutinous rice x wild rice

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Mao Dezhi; Tang Yilan

1998-01-01

The hybrid rice F 1 plant derived from the back crossing of glutinous rice x wild rice was irradiated with γ-ray. The result of investigation to the induced mutant showed that through the selection and backcross, a black glutinous rice strain with the short stem, cold tolerance and high yield was developed. The analysis of the ability of heredity variance showed that the selection was effective for the husk colour, black glutinous and black Indica rice, but ineffective for the white Indica rice and seed setting

Overexpression of rice thaumatin-like protein (Ostlp gene in transgenic cassava results in enhanced tolerance to Colletotrichum gloeosporioides f. sp. manihotis

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Patroba Odeny Ojola

2018-06-01

Full Text Available Cassava (Manihot esculenta Crantz is the most important staple food for more than 300 million people in Africa, and anthracnose disease caused by Colletotrichum gloeosporioides f. sp. manihotis is the most destructive fungal disease affecting cassava production in sub-Saharan Africa. The main objective of this study was to improve anthracnose resistance in cassava through genetic engineering. Transgenic cassava plants harbouring rice thaumatin-like protein (Ostlp gene, driven by the constitutive CaMV35S promoter, were generated using Agrobacterium-mediated transformation of friable embryogenic calli (FEC of cultivar TMS 60444. Molecular analysis confirmed the presence, integration, copy number of the transgene all the independent transgenic events. Semi-quantitative RT-PCR confirmed high expression levels of Ostlp in six transgenic lines tested. The antifungal activity of the transgene against Colletotrichum gloeosporioides pathogen was evaluated using the leaves and stem cuttings bioassay. The results demonstrated significantly delayed disease development and reduced size of necrotic lesions in leaves and stem cuttings of all transgenic lines compared to the leaves and stem cuttingss of non-transgenic control plants. Therefore, constitutive overexpression of rice thaumatin-like protein in transgenic cassava confers enhanced tolerance to the fungal pathogen C. gloeosporioides f. sp. manihotis. These results can therefore serve as an initial step towards genetic engineering of farmer-preffered cassava cultivars for resistance to anthracnose disease. Keywords: Colletotrichum gloeosporioides f. sp. manihotis, Thaumatin-like protein, Transgenic cassava

The accumulation of two neolignan in the leaves, stems, and flower of red betel (Piper crocatum Ruiz & Pav.)

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Hartini, Y. S.; Nugroho, L.

2017-05-01

Organ for the biosynthesis of secondary metabolite is not always a place for its biosynthesis, even the same compound was synthesized in the different organs in different plants. Neolignan is a secondary metabolite, known as an imunostimulant, synthesized through shikimic acid pathway with the important precursor is chorismic acid. The compound was known to be accumulated in the roots, stems and leaves of Piper regnellii with the concentration varies depending on the type of neolignan. It has been investigated the accumulation of two compound neolignans (Pc-1 and Pc-2) isolated from the methanol extract of red betel leaf (Piper crocatum Ruiz & Pav.) in the leaves, stems, and flowers of red betel. Chromatographic methods used was Gas Chromatography-Mass Spectrometry (GC-MS). Chromatogram of GC-MS showed that the Pc-1 with purity of 100%, m/z 460.3 could be detected at the minute of 29.986, while the Pc-2 with purity of 96.681%, m/z 418.3 was detected at the minute of 29.495. The research was then continued to investigate the existence and accumulation of both compounds in leaves, stems, and flowers of red betel. The GC-MS chromatogram shows that Pc-1 and Pc-2 could be detected in the leaves, stem and flower with various concentration among plant organs. Moreover, leaves contained the highest concentration of Pc-1 and Pc-2 compared to other plant organs.

Evaluation of Bt (Bacillus thuringiensis) rice varieties against stem borer (Chilo suppressalis).

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Kiani, Ghaffar; Nematzadeh, Ghorban Ali; Ghareyazie, Behzad; Sattari, Majid

2008-02-15

Three transgenic rice varieties namely Khazar, Neda and Nemat, all containing a cry1Ab gene, were evaluated through PCR analysis and field examinations for their resistance at natural infestation of insect pests during 2007. The results showed that all transgenic varieties produced 1.2 kb PCR product derived from application of cry1Ab gene. In field conditions, transgenic varieties exhibited high levels of resistance against natural infestation of stem borer and the damaged plants based on dead heart or white heat for them were less than 1%. Moreover, in stem-cut bioassay 100% of released larvae died within four days after infestation. These results demonstrate that expression of cry1Ab gene in the genome of transgenic varieties provided season-long protection from the natural infestation of lepidopteran insects.

Effects of Aluminium Sulfate on Cadmium Accumulation in Rice

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Khamvarn, Vararas; Boontanon, Narin; Prapagdee, Benjaphorn; Kumsopa, Acharaporn; Boonsirichai, Kanokporn

2011-06-01

Full text: Cadmium accumulation in Pathum Thani 1 and Suphan Buri 60 rice cultivars was investigated upon treatment with aluminium sulfate as a precipitant. Rice was grown hydroponically in a medium containing 4 ppm cadmium nitrate with or without 4 ppm aluminium sulfate. Root, stem with leaves and grain samples were collected and analyzed for cadmium content using atomic absorption spectroscopy and inductively coupled plasma atomic emission spectroscopy. Without the addition of aluminium sulfate, Pathum Thani 1 and Suphan Buri 60 accumulated 24.71∫ 3.14 ppm and 34.43 ∫ 4.51 ppm (dry weight of whole plant) of cadmium, respectively. With aluminium sulfate, cadmium accumulation increased to 40.66 ∫ 2.47 ppm and 62.94 ∫ 10.69 ppm, respectively. The addition of aluminium sulfate to the planting medium did not reduce cadmium accumulation but caused the rice to accumulate more cadmium especially in the shoots and grains. This observation might serve as the basis for future research on the management of agricultural areas that are contaminated with cadmium and aluminium

Cuticle ultrastructure, cuticular lipid composition, and gene expression in hypoxia-stressed Arabidopsis stems and leaves.

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Kim, Hyojin; Choi, Dongsu; Suh, Mi Chung

2017-06-01

An increased permeability of the cuticle is closely associated with downregulation of genes involved in cuticular lipid synthesis in hypoxia-stressed Arabidopsis and may allow plants to cope with oxygen deficiency. The hydrophobic cuticle layer consisting of cutin polyester and cuticular wax is the first barrier to protect the aerial parts of land plants from environmental stresses. In the present study, we investigated the role of cuticle membrane in Arabidopsis responses to oxygen deficiency. TEM analysis showed that the epidermal cells of hypoxia-treated Arabidopsis stems and leaves possessed a thinner electron-translucent cuticle proper and a more electron-dense cuticular layer. A reduction in epicuticular wax crystal deposition was observed in SEM images of hypoxia-treated Arabidopsis stem compared with normoxic control. Cuticular transpiration was more rapid in hypoxia-stressed leaves than in normoxic control. Total wax and cutin loads decreased by approximately 6-12 and 12-22%, respectively, and the levels of C29 alkanes, secondary alcohols, and ketones, C16:0 ω-hydroxy fatty acids, and C18:2 dicarboxylic acids were also prominently reduced in hypoxia-stressed Arabidopsis leaves and/or stems relative to normoxic control. Genome-wide transcriptome and quantitative RT-PCR analyses revealed that the expression of several genes involved in the biosynthesis and transport of cuticular waxes and cutin monomers were downregulated more than fourfold, but no significant alterations were detected in the transcript levels of fatty acid biosynthetic genes, BCCP2, PDH-E1α, and ENR1 in hypoxia-treated Arabidopsis stems and leaves compared with normoxic control. Taken together, an increased permeability of the cuticle is closely associated with downregulation of genes involved in cuticular lipid synthesis in hypoxia-stressed Arabidopsis. The present study elucidates one of the cuticle-related adaptive responses that may allow plants to cope with low oxygen levels.

ZrO2/bamboo leaves ash (BLA) Catalyst in Biodiesel Conversion of Rice Bran Oil

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Fatimah, Is; Taushiyah, Ana; Badriatun Najah, Fitri; Azmi, Ulil

2018-04-01

Preparation, characterization and catalytic activity of ZrO2/bamboo leaves ash (BLA) catalyst for conversion of rice bran oil to biodiesel have been investigated. The catalyst was prepared by impregnation method of ZrOCl2 as ZrO2 precursor with BLA at a theoretical content of 20% wt. followed by calcination. The physicochemical properties of the catalyst material were characterized by x-ray diffraction (XRD), FTIR and surface acidity measurement. Activity test of materials in biodiesel conversion of rice bran oil was used by reflux method and microwave (MW) assisted method. Reaction variables studied in the investigation were the effect of catalyst weight and time of MW irradiation compared with the use reflux method. The results showed that ZrO2/BLA catalyst exhibited competitively effective and efficient processes for the production of biodiesel. The reflux method demonstrated an higher conversion (%) compared to MW method, however MW method showed the better reusable properties.

Briquettes of rice husk, polyethylene terephthalate (PET), and dried leaves as implementation of wastes recycling

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Hariyanto, Sucipto; Usman, Mohammad Nurdianfajar; Citrasari, Nita

2017-06-01

This research aim is to determine the best briquettes as implementation of wastes recycle based on scoring method, main component composition, compressive strength, caloric value, water content, vollatile content, and ash content, also the suitability with SNI 01-6235-2000. Main component that used are rice husk, 2mm and 6 mm PET, and dried leaves. Composition variation in this research are marked as K1, K2, K3, K4, and K5 with 2 mm PET plastic and K1, K2, K3, K4, and K5 with 6 mm PET plastic. The total weight of the briquettes is 100 g and divided into 90% main components and 10% tapioca as binder. The compressive strength, caloric value, water content, vollatile content, and ash content were tested according to ASTM D 5865-04, ASTM D 3173-03, ASTM D 3175-02, ASTM D 3174-02. The tested results were used to determine the best briquette by scoring method, and the chosen briquettes is K2 with 6 mm PET plastic. The composition is 70% rice husk, 20% 6 mm PET plastic, and 10% dried leaves with the compressive strength, caloric value, water content, vollatile content, and ash content value is 51,55 kg/cm2; 5123 kal/g; 3,049%; 31,823%, dan 12,869%. The suitable value that meet the criteria according to SNI 01-6235-2000 is compressive strength, caloric value, water content, and ash content.

Biogeographical patterns of biomass allocation in leaves, stems, and roots in China’s forests

Science.gov (United States)

Zhang, Hao; Wang, Kelin; Xu, Xianli; Song, Tongqing; Xu, Yanfang; Zeng, Fuping

2015-01-01

To test whether there are general patterns in biomass partitioning in relation to environmental variation when stand biomass is considered, we investigated biomass allocation in leaves, stems, and roots in China’s forests using both the national forest inventory data (2004–2008) and our field measurements (2011–2012). Distribution patterns of leaf, stem, and root biomass showed significantly different trends according to latitude, longitude, and altitude, and were positively and significantly correlated with stand age and mean annual precipitation. Trade-offs among leaves, stems, and roots varied with forest type and origin and were mainly explained by stand biomass. Based on the constraints of stand biomass, biomass allocation was also influenced by forest type, origin, stand age, stand density, mean annual temperature, precipitation, and maximum temperature in the growing season. Therefore, after stand biomass was accounted for, the residual variation in biomass allocation could be partially explained by stand characteristics and environmental factors, which may aid in quantifying carbon cycling in forest ecosystems and assessing the impacts of climate change on forest carbon dynamics in China. PMID:26525117

Neofusicoccum parvum Colonization of the Grapevine Woody Stem Triggers Asynchronous Host Responses at the Site of Infection and in the Leaves

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Mélanie Massonnet

2017-06-01

Full Text Available Grapevine trunk diseases cause important economic losses in vineyards worldwide. Neofusicoccum parvum, one of the most aggressive causal agents of the trunk disease Botryosphaeria dieback, colonizes cells and tissues of the grapevine wood, leading to the formation of an internal canker. Symptoms then extend to distal shoots, with wilting of leaves and bud mortality. Our aim was to characterize the transcriptional dynamics of grapevine genes in the woody stem and in the leaves during Neofusicoccum parvum colonization. Genome-wide transcriptional profiling at seven distinct time points (0, 3, and 24 hours; 2, 6, 8, and 12 weeks showed that both stems and leaves undergo extensive transcriptomic reprogramming in response to infection of the stem. While most intense transcriptional responses were detected in the stems at 24 hours, strong responses were not detected in the leaves until the next sampling point at 2 weeks post-inoculation. Network co-expression analysis identified modules of co-expressed genes common to both organs and showed most of these genes were asynchronously modulated. The temporal shift between stem vs. leaf responses affected transcriptional modulation of genes involved in both signal perception and transduction, as well as downstream biological processes, including oxidative stress, cell wall rearrangement and cell death. Promoter analysis of the genes asynchronously modulated in stem and leaves during N. parvum colonization suggests that the temporal shift of transcriptional reprogramming between the two organs might be due to asynchronous co-regulation by common transcriptional regulators. Topology analysis of stem and leaf co-expression networks pointed to specific transcription factor-encoding genes, including WRKY and MYB, which may be associated with the observed transcriptional responses in the two organs.

Chemical diversity of essential oils from flowers,leaves,and stems of Rhanterium epapposum Oliv. growing in northern border region of Saudi Arabia

Institute of Scientific and Technical Information of China (English)

Marwa Awad; Abdelrhman Abdelwahab

2016-01-01

Objective:To evaluate the medicinal uses of Rhanterium epapposum Oliv.(R.epapposum) growing in northern border region of Saudi Arabia,through the chemical diversity of essential oils extracted from its flowers,leaves and stems.Methods:Aerial parts of R.epapposum were collected in April 2014.Air dried flowers,leaves,and stems were separately subjected to hydrodistillation in a Clevenger-type apparatus for 4 h to extract the essential oils.Gas chromatography-mass spectrometry analysis of the essential oils was carried out using an Agilent 6890 gas chromatograph equipped with an Agilent 5973 mass spectrometric detector.Results:A total of 51 compounds representing 76.35%–94.86% of flowers,leaves and stems oils composition were identified.The chemical profiles of the studied fractions revealed the dominance of monoterpenes,regardless of qualitative and quantitative differences observed.Limonene,linalool,4-terpineol and a-cadinol represented the major constituents of flowers oil.Leaves oil was dominated by limonene,sabinene,a-pinene and b-myrcene whereas linalool,ionole,a-cadinol,b-eudesmol,4-terpineol,and aterpineol were the major constituents of stems oil.Conclusions:Essential oils from flowers,leaves and stems of R.epapposum growing in northern border region of Saudi Arabia are considered as a rich source of monoterpenes which have biological activities.

Characterization of 68Zn uptake, translocation, and accumulation into developing grains and young leaves of high Zn-density rice genotype*

Science.gov (United States)

Wu, Chun-yong; Feng, Ying; Shohag, Md. Jahidul Islam; Lu, Ling-li; Wei, Yan-yan; Gao, Chong; Yang, Xiao-e

2011-01-01

Zinc (Zn) is an essential micronutrient for humans, but Zn deficiency has become serious as equally as iron (Fe) and vitamin A deficiencies nowadays. Selection and breeding of high Zn-density crops is a suitable, cost-effective, and sustainable way to improve human health. However, the mechanism of high Zn density in rice grain is not fully understood, especially how Zn transports from soil to grains. Hydroponics experiments were carried out to compare Zn uptake and distribution in two different Zn-density rice genotypes using stable isotope technique. At seedling stage, IR68144 showed higher 68Zn uptake and transport rate to the shoot for the short-term, but no significant difference was observed in both genotypes for the long-term. Zn in xylem sap of IR68144 was consistently higher, and IR68144 exhibited higher Zn absorption ratio than IR64 at sufficient (2.0 µmol/L) or surplus (8.0 µmol/L) Zn supply level. IR64 and IR68144 showed similar patterns of 68Zn accumulation in new leaves at seedling stage and in developing grains at ripening stage, whereas 68Zn in new leaves and grains of IR68144 was consistently higher. These results suggested that a rapid root-to-shoot translocation and enhanced xylem loading capacity may be the crucial processes for high Zn density in rice grains. PMID:21528496

The accumulation of two neolignan in the leaves, stems, and flower of red betel ( Piper crocatum Ruiz and Pav.)

International Nuclear Information System (INIS)

Hartini, Y S; Nugroho, L

2017-01-01

Organ for the biosynthesis of secondary metabolite is not always a place for its biosynthesis, even the same compound was synthesized in the different organs in different plants. Neolignan is a secondary metabolite, known as an imunostimulant, synthesized through shikimic acid pathway with the important precursor is chorismic acid. The compound was known to be accumulated in the roots, stems and leaves of Piper regnellii with the concentration varies depending on the type of neolignan. It has been investigated the accumulation of two compound neolignans (Pc-1 and Pc-2) isolated from the methanol extract of red betel leaf ( Piper crocatum Ruiz and Pav.) in the leaves, stems, and flowers of red betel. Chromatographic methods used was Gas Chromatography-Mass Spectrometry (GC-MS). Chromatogram of GC-MS showed that the Pc-1 with purity of 100%, m/z 460.3 could be detected at the minute of 29.986, while the Pc-2 with purity of 96.681%, m/z 418.3 was detected at the minute of 29.495. The research was then continued to investigate the existence and accumulation of both compounds in leaves, stems, and flowers of red betel. The GC-MS chromatogram shows that Pc-1 and Pc-2 could be detected in the leaves, stem and flower with various concentration among plant organs. Moreover, leaves contained the highest concentration of Pc-1 and Pc-2 compared to other plant organs. (paper)

Photochemical oxidants injury in rice plants. III. Effect of ozone on physiological activities in rice plants

Energy Technology Data Exchange (ETDEWEB)

Nakamura, H; Saka, H

1978-01-01

Experiments were made to determine the effect of photochemical oxidants on physiological activities of rice plants. Rice plants were fumigated with ozone at concentrations of 0.12-0.20 ppm for 2-3 hr to investigate acute injury and at 0.05 and 0.09 ppm for daily exposure from 3.0 leaf stage to assess the effect of ozone on growth. It was observed that malondialdehyde produced by disruption of the components of the membrane increased in the leaves exposed to ozone. Ozone reduced the RuBP-carboxylase activity in both young and old leaves 12-24 hr after fumigation. In the young leaves the activity of this enzyme recovered to some extent after 48 hr, but it did not show any recovery in the old leaves. On the other hand, ozone remarkably increased the peroxidase activity and slightly increased acid phosphatase in all leaves. Abnormally high ethylene evolution and oxygen uptake were detected in leaves soon after ozone fumigation. In general, high molecular protein and chlorophyll contents in the detached leaves decreased with incubation in dark, particularly in the old ones. These phenomena were more accelerated by ozone fumigation. Kinetin and benzimidazole showed significant effects on chlorophyll retention in ozone-exposed leaves. Reduction of plant growth and photosynthetic rate was recognized even in low concentration of ozone in daily exposure at 0.05 and 0.09 ppm. From these results it was postulated that ozone may cause the senescence of leaves in rice plants.

[Effects of soil water status on gas exchange of peanut and early rice leaves].

Science.gov (United States)

Chen, Jiazhou; Lü, Guoan; He, Yuanqiu

2005-01-01

The gas exchange characteristics of peanut and early rice leaves were investigated in experimental plots under different soil water conditions over a long growth period. The results showed that at the branching stage of peanut, the stomatal conductance (Gs) and transpiration rate (Tr) decreased slightly under mild and moderate soil water stress, while the net photosynthetic rate (Pn) and leaf water use efficiency (WUE) increased. The Gs/Tr ratio also increased under mild water stress, but decreased under moderate water stress. At podding stage, the Gs, Tr, Gs/Tr ratio and Pn decreased, while WUE increased significantly under mild and moderate water stress. The peanut was suffered from water stress at its pod setting stage. At the grain filling stage of early rice, the Gs, Tr and Gs/Tr ratio fluctuated insignificantly under mild and moderate water stress, while Pn and WUE increased significantly, with an increase in grain yield under mild water stress. It's suggested that the combination of Gs and Gs/Tr ratio could be a reference index for crop water stress, namely, crops could be hazarded by water stress when Gs and Gs/Tr decreased synchronously.

Analysis of essential oils of leaves, stems, flowers and rhizomes of Etlingera elatior (Jack) R.M. Smith

International Nuclear Information System (INIS)

Faridahanim Mohd Jaafar; Che Puteh Osman; Nor Hadiani Ismail; Khalijah Awang

2007-01-01

The essential oils from leaves, stems, flowers and rhizomes of Etlingera elatior, an aromatic plant that are widely used in traditional medicine and as a flavour in local dishes were extracted. The essential oils were extracted using the hydro distillation method and analysed by GC-MS. The percentage yield of volatile constituents of the leaves, stems, flowers and rhizomes were 0.0735%, 0.0029%, 0.0334% and 0.0021%, respectively. The leaf essential oil contained β- pinene (19.7%), caryophyllene (15.36%) and (E)-β-farnesene (27.90%) as major compounds whereas the stem essential oil were largely dominated by 1,1-dodecanediol diacetate (34.26%) and (E)-5-dodecane (26.99%). The essential oils of the flowers and rhizomes contained the major compounds 1, 1- dodecanediol diacetate (24.38% and 40.37% respectively) and cyclododecane (47.28% and 34.45% respectively). (author)

Study on rice absorption and distribution of Cd in applying Zn fertilizer with 65Zn, 115Cdm tracing technique

International Nuclear Information System (INIS)

Tang Nianxin; Shen Jinxiong

1994-01-01

Results of study by using 65 Zn and 115 Cd m tracers show that, along with the increase of the amount of Cd in applying Zn fertilizer to soil, rice has the phenomena of growth retard and tiller delay in the earlier growing stage. The inhibiting phenomenon is lightened along with the progress of rice growth. Very small quantity of Cd might be helpful to the growth of rice. It would cause serious inhibition to rice growth when the amount of Cd reaches to a definite limitation (64 x 10 -6 ). The distribution of Cd in a rice plant follows the following order in content: root>stem and leaves>brown rice>ear stalk>rice shell. Cd is mainly accumulated in rice root, taking 90% of the total amount of Cd contained in whole rice plant. The amount of Cd absorbed by rice increases with the amount of Cd applied to soil, though the total absorption extremely low, for example, only about 0.1% of the applied amount could be absorbed by two crops of rice, most of the applied Cd still retains in soil. Less and less Zn could be absorbed and utilized by rice along with the increase of the amount of the applied Cd. Application of Mn fertilizer affects negatively the absorption of Cd by rice, especially in brown rice

The Evolutionary Basis of Naturally Diverse Rice Leaves Anatomy.

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Jolly Chatterjee

Full Text Available Rice contains genetically and ecologically diverse wild and cultivated species that show a wide variation in plant and leaf architecture. A systematic characterization of leaf anatomy is essential in understanding the dynamics behind such diversity. Therefore, leaf anatomies of 24 Oryza species spanning 11 genetically diverse rice genomes were studied in both lateral and longitudinal directions and possible evolutionary trends were examined. A significant inter-species variation in mesophyll cells, bundle sheath cells, and vein structure was observed, suggesting precise genetic control over these major rice leaf anatomical traits. Cellular dimensions, measured along three growth axes, were further combined proportionately to construct three-dimensional (3D leaf anatomy models to compare the relative size and orientation of the major cell types present in a fully expanded leaf. A reconstruction of the ancestral leaf state revealed that the following are the major characteristics of recently evolved rice species: fewer veins, larger and laterally elongated mesophyll cells, with an increase in total mesophyll area and in bundle sheath cell number. A huge diversity in leaf anatomy within wild and domesticated rice species has been portrayed in this study, on an evolutionary context, predicting a two-pronged evolutionary pathway leading to the 'sativa leaf type' that we see today in domesticated species.

Toxicity of essential oils from leaves of Piperaceae species in rice stalk stink bug eggs, Tibraca limbativentris (Hemiptera: Pentatomidae

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Diones Krinski

Full Text Available ABSTRACT Tibraca limbativentris to is an important rice pest and occurs in all rice-growing regions of Latin America. The control this insect is accomplished with synthetic chemical insecticides, however, new approaches are needed to reduce risks to the environment, to the natural enemies and also to avoid the onset of insecticides resistance. This study was designed to assess the toxicity of essential oils (EOs from leaves of Piper aduncum, P. gaudichaudianum, P. malacophyllum, P. marginatum and P. tuberculatum (Piperaceae on rice stalk stink bug eggs, T. limbativentris. Essential oils were extracted with steam distillation and dilutions were made for bioassays at concentrations of 0.25; 0.5; 1.0; 2.0 and 4.0%. Essential oils from all species of Piperaceae displayed ovicidal activity. The LC50 values indicated that both younger and older eggs were susceptible to these oils. Ovicidal activity is related to the potential toxicity of several compounds, especially dilapiolle, myristicin, cubebene, α-guaiene, longifolene, prezizane, spathulenol, sabinene and δ-2-carene. Thus, EOs tested showed promising results for use as biorational botanical insecticides.

Linkage Mapping of Stem Saccharification Digestibility in Rice.

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Bohan Liu

Full Text Available Rice is the staple food of almost half of the world population, and in excess 90% of it is grown and consumed in Asia, but the disposal of rice straw poses a problem for farmers, who often burn it in the fields, causing health and environmental problems. However, with increased focus on the development of sustainable biofuel production, rice straw has been recognized as a potential feedstock for non-food derived biofuel production. Currently, the commercial realization of rice as a biofuel feedstock is constrained by the high cost of industrial saccharification processes needed to release sugar for fermentation. This study is focused on the alteration of lignin content, and cell wall chemotypes and structures, and their effects on the saccharification potential of rice lignocellulosic biomass. A recombinant inbred lines (RILs population derived from a cross between the lowland rice variety IR1552 and the upland rice variety Azucena with 271 molecular markers for quantitative trait SNP (QTS analyses was used. After association analysis of 271 markers for saccharification potential, 1 locus and 4 pairs of epistatic loci were found to contribute to the enzymatic digestibility phenotype, and an inverse relationship between reducing sugar and lignin content in these recombinant inbred lines was identified. As a result of QTS analyses, several cell-wall associated candidate genes are proposed that may be useful for marker-assisted breeding and may aid breeders to produce potential high saccharification rice varieties.

Transfer of gaseous iodine (I2) from atmosphere to rice grains through dry deposition

International Nuclear Information System (INIS)

Uchida, Shigeo; Muramatsu, Yasuyuki; Sumiya, Misako; Ohmomo, Yoichiro

1989-01-01

The report briefly outlines parameters required to determine the transfer of 129 I from the atmosphere to rice grains, and presents results of a study in which the transfer of iodine from the atmosphere to rice grains is calculated using empirically determined parameters. There are four major parameters required for the calculation: (1) the major transfer route (translocation either from leaves or from the surface of hulls to rice grains), (2) rate of deposition onto the surface of leaves or hulls, (3) biological half-life of iodine deposited on leaves or hulls, and (4) either the rate of translocation from leaves to hulls (where the translocation from leaves is the major route) or the ratio of iodine distribution among hulls, unpolished rice grains, and polished rice grains (where the translocation from hulls is the major route). Techniques available to determine the translocation route, deposition rate, biological half-life and distribution ratio are outlined. Chemical forms of iodine, parameters relating to the transfer of gaseous iodine to paddy rice, and calculation models are also described. (N,K.)

Two-line hybrid rice male sterile line 'NHR111S' with a marker of green-revertible albino leaves

International Nuclear Information System (INIS)

Wu Wei; Liu Xin; Shu Xiaoli; Shu Qingyao; Xia Yingwu; Wu Dianxing

2006-01-01

NHR111S is a new two-line male sterile line with a marker of green-revertible albino leave that was bred from in vitro mutagens is of the thermo/photoperiod-sensitive male sterile line 'Guangzhan63S' by 60 Co γ-rays. It has the same desired agronomic traits, fertility characteristics and combining ability as characteristics of the parent. It is convenient to develop leaf color marker-aided elimination strategy in the multiplication and production of hybrid rice seeds. (authors)

Stem water storage in five coexisting temperate broad-leaved tree species: significance, temporal dynamics and dependence on tree functional traits.

Science.gov (United States)

Köcher, Paul; Horna, Viviana; Leuschner, Christoph

2013-08-01

The functional role of internal water storage is increasingly well understood in tropical trees and conifers, while temperate broad-leaved trees have only rarely been studied. We examined the magnitude and dynamics of the use of stem water reserves for transpiration in five coexisting temperate broad-leaved trees with largely different morphology and physiology (genera Fagus, Fraxinus, Tilia, Carpinus and Acer). We expected that differences in water storage patterns would mostly reflect species differences in wood anatomy (ring vs. diffuse-porous) and wood density. Sap flux density was recorded synchronously at five positions along the root-to-branch flow path of mature trees (roots, three stem positions and branches) with high temporal resolution (2 min) and related to stem radius changes recorded with electronic point dendrometers. The daily amount of stored stem water withdrawn for transpiration was estimated by comparing the integrated flow at stem base and stem top. The temporal coincidence of flows at different positions and apparent time lags were examined by cross-correlation analysis. Our results confirm that internal water stores play an important role in the four diffuse-porous species with estimated 5-12 kg day(-1) being withdrawn on average in 25-28 m tall trees representing 10-22% of daily transpiration; in contrast, only 0.5-2.0 kg day(-1) was withdrawn in ring-porous Fraxinus. Wood density had a large influence on storage; sapwood area (diffuse- vs. ring-porous) may be another influential factor but its effect was not significant. Across the five species, the length of the time lag in flow at stem top and stem base was positively related to the size of stem storage. The stem stores were mostly exhausted when the soil matrix potential dropped below -0.1 MPa and daily mean vapor pressure deficit exceeded 3-5 hPa. We conclude that stem storage is an important factor improving the water balance of diffuse-porous temperate broad-leaved trees in moist

Gravimorphism in rice and barley: promotion of leaf elongation by vertical inversion in agravitropically growing plants.

Science.gov (United States)

Abe, K; Takahashi, H; Suge, H

1998-12-01

We have compared shoot responses of agravitropic rice and barley plants to vertical inversion with those of normal ones. When rice plants were vertically inverted, the main stems of a japonica type of rice, cv. Kamenoo, showed negative gravitropism at nodes 2-15 of both elongated and non-elongated internodes. However, shoots of lazy line of rice, lazy-Kamenoo, bent gravitropically at nodes 11-15 only elongated internodes but not at nodes 2-10 of non-elongated ones. Thus, shoots of Kamenoo responded gravitropically at all stages of growth, whereas shoots of lazy-Kamenoo did not show gravitropic response before heading. In Kamenoo plants, lengths of both leaf-sheath and leaf-blade were shortened by vertical inversion, but those of the vertically inverted plants of lazy-Kamenoo were significantly longer than the plants in an upright position. When agravitropic and normal plants of barley were vertically inverted, the same results as in rice were obtained; elongation of both leaf-sheath and leaf-blade was inhibited in normal barley plants, Chikurin-Ibaragi No. 1, but significantly stimulated in agravitropic plants of serpentina barley. These results suggest that vertical inversion of rice and barley plants enhances the elongation growth of leaves in the absence of tropistic response.

Endophytic Colonization and In Planta Nitrogen Fixation by a Herbaspirillum sp. Isolated from Wild Rice Species

Science.gov (United States)

Elbeltagy, Adel; Nishioka, Kiyo; Sato, Tadashi; Suzuki, Hisa; Ye, Bin; Hamada, Toru; Isawa, Tsuyoshi; Mitsui, Hisayuki; Minamisawa, Kiwamu

2001-01-01

Nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified Rennie medium. Based on 16S ribosomal DNA (rDNA) sequences, the diazotrophic isolates were phylogenetically close to four genera: Herbaspirillum, Ideonella, Enterobacter, and Azospirillum. Phenotypic properties and signature sequences of 16S rDNA indicated that three isolates (B65, B501, and B512) belong to the Herbaspirillum genus. To examine whether Herbaspirillum sp. strain B501 isolated from wild rice, Oryza officinalis, endophytically colonizes rice plants, the gfp gene encoding green fluorescent protein (GFP) was introduced into the bacteria. Observations by fluorescence stereomicroscopy showed that the GFP-tagged bacteria colonized shoots and seeds of aseptically grown seedlings of the original wild rice after inoculation of the seeds. Conversely, for cultivated rice Oryza sativa, no GFP fluorescence was observed for shoots and only weak signals were observed for seeds. Observations by fluorescence and electron microscopy revealed that Herbaspirillum sp. strain B501 colonized mainly intercellular spaces in the leaves of wild rice. Colony counts of surface-sterilized rice seedlings inoculated with the GFP-tagged bacteria indicated significantly more bacterial populations inside the original wild rice than in cultivated rice varieties. Moreover, after bacterial inoculation, in planta nitrogen fixation in young seedlings of wild rice, O. officinalis, was detected by the acetylene reduction and 15N2 gas incorporation assays. Therefore, we conclude that Herbaspirillum sp. strain B501 is a diazotrophic endophyte compatible with wild rice, particularly O. officinalis. PMID:11679357

Control of the synthesis and subcellular targeting of the two GDH genes products in leaves and stems of Nicotiana plumbaginifolia and Arabidopsis thaliana.

Science.gov (United States)

Fontaine, Jean-Xavier; Saladino, Francesca; Agrimonti, Caterina; Bedu, Magali; Tercé-Laforgue, Thérèse; Tétu, Thierry; Hirel, Bertrand; Restivo, Francesco M; Dubois, Frédéric

2006-03-01

Although the physiological role of the enzyme glutamate dehydrogenase which catalyses in vitro the reversible amination of 2-oxoglutarate to glutamate remains to be elucidated, it is now well established that in higher plants the enzyme preferentially occurs in the mitochondria of phloem companion cells. The Nicotiana plumbaginifolia and Arabidopis thaliana enzyme is encoded by two distinct genes encoding either an alpha- or a beta-subunit. Using antisense plants and mutants impaired in the expression of either of the two genes, we showed that in leaves and stems both the alpha- and beta-subunits are targeted to the mitochondria of the companion cells. In addition, we found in both species that there is a compensatory mechanism up-regulating the expression of the alpha-subunit in the stems when the expression of the beta-subunit is impaired in the leaves, and of the beta-subunit in the leaves when the expression of the alpha-subunit is impaired in the stems. When one of the two genes encoding glutamate dehydrogenase is ectopically expressed, the corresponding protein is targeted to the mitochondria of both leaf and stem parenchyma cells and its production is increased in the companion cells. These results are discussed in relation to the possible signalling and/or physiological function of the enzyme which appears to be coordinated in leaves and stems.

Biomass production and essential oil yield from leaves, fine stems and resprouts using pruning the crown of Aniba canelilla (H.B.K.) (Lauraceae) in the Central Amazon

OpenAIRE

Manhães,Adriana Pellegrini; Veiga-Júnior,Valdir Florêncio da; Wiedemann,Larissa Silveira Moreira; Fernandes,Karenn Silveira; Sampaio,Paulo de Tarso Barbosa

2012-01-01

Aniba canelilla (H.B.K.) Mez. is a tree species from Amazon that produces essential oil. The oil extraction from its leaves and stems can be an alternative way to avoid the tree cutting for production of essential oil. The aim of this study was to analyse factors that may influence the essential oil production and the biomass of resprouts after pruning the leaves and stems of A. canelilla trees. The tree crowns were pruned in the wet season and after nine months the leaves and stems of the re...

The overexpression of insect endogenous small RNAs in transgenic rice inhibits growth and delays pupation of striped stem borer (Chilo suppressalis).

Science.gov (United States)

Jiang, Shan; Wu, Hao; Liu, Haoju; Zheng, Jie; Lin, Yongjun; Chen, Hao

2017-07-01

The striped stem borer (SSB), Chilo suppressalis Walker, is a major rice insect pest worldwide. RNA interference (RNAi) has become a promising strategy for developing insect-resistant crops. In a previous study, five double-stranded RNAs (dsRNAs) targeting important SSB housekeeping genes were overexpressed in rice, but none of the acquired dsRNA-transgenic rice plants showed significant effects on SSB. Thirteen selected SSB endogenous small RNAs, predicted as SSB novel microRNAs (miRNAs), were overexpressed in rice using artificial miRNA (amiRNA) expression technology. Feeding tests showed that two out of 13 selected SSB novel miRNAs caused significant growth inhibition for feeding SSB larvae based on transgenic rice expression. Pupation was delayed 4 days when SSB larvae consecutively fed on transgenic rice expressing the SSB novel miRNA candidate csu-novel-miR15 (csu-15 rice). Gene expression analysis confirmed that the expression levels of at least six SSB unigenes significantly changed (i.e., were up- or down-regulated) after feeding on csu-15 rice. Our research demonstrated a novel RNAi strategy using SSB endogenous small RNAs to develop RNAi crops for pest management; this strategy is different from the common RNAi resulting from transgenic dsRNAs or amiRNAs targeting certain insect endogenous genes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Quantification of Catechin in Leaves and Stems of Malaysian Uncaria Gambir (Hunter) ROXB. by HPLC-DAD

International Nuclear Information System (INIS)

Nurliayana Ibrahim; Nurul Zulaikha Mohd Yusoff; Rohaya Ahmad; Rohaya Ahmad

2016-01-01

Recently, we reported the isolation of a novel flavonoid named uncariechin along with epicatechin and epiafzelechin from the leaf extract of Uncaria longiflora variety pteropoda (Miq.) Ridsd. of the family Rubiaceae. Continuing our investigation on the Uncaria genus, the identification and quantification of its phytoconstituents was carried out. The species of particular interest is the Malaysian Uncaria gambir. This species is distributed mainly in Malaysia and Indonesia and has been cultivated for the flavonoid catechin in Indonesia. Hence, the objective of this study is to determine the quantity of catechin in hexane (Hx), dichloromethane (DCM) and methanol (MeOH) extracts in both stem and leaf parts of the plant via HPLC-DAD. Our findings indicate that catechin is present in higher amounts in the MeOH extract [8.64 % (leaves); 5.12 % (stems)] compared to the DCM extract [0.77 % (leaves); 0.92 % (stems)] with no catechin found in the hexane extract. This is the first report of the quantification of catechin from Malaysian U. gambir using HPLC-DAD. The method can be used for the quantification of flavonoids from other Uncaria and related genus and is useful for targeted isolation of interest flavonoids. (author)

Differential fipronil susceptibility and metabolism in two rice stem borers from China.

Science.gov (United States)

Fang, Qi; Huang, Cheng-Hua; Ye, Gong-Yin; Yao, Hong-Wei; Cheng, Jia-An; Akhtar, Zunnu-Raen

2008-08-01

The susceptibilities of larvae of two rice stem borers, namely, Chilo suppressalis (Walker) (Lepidoptera: Crambidae) and Sesamia inferens (Walker) (Lepidoptera: Nocutidae) to fipronil and its metabolites were investigated, and then the activities of microsomal O-demethylase, and glutathione transferase (GST) in two species were measured. The metabolism of fipronil in both stem borers was determined in vivo and in vitro. The LD50 value of fipronil to S. inferens was 118.5-fold higher than that of C. suppressalis. The bioassay results offipronil metabolites showed that the toxicities of sulfone and sulfide were higher than fipronil for both species, and the differential toxicity between sulfone and fipronil was remarkable. Alternatively, the activities of microsomal O-demethylase and GST of C. suppressalis were 1.35- and 2.06-fold higher than S. inferens, respectively. The in vivo and in vitro studies on metabolism of fipronil showed that all of fipronil, sulfone, and sulfide were detected and the content of sulfone was higher than sulfide in both stem borers. The residue of sulfone in C. suppressalis was significantly higher than that in S. inferens. These results suggest that the higher activity of mixed function oxidases may cause the higher capacity of C. suppressalis to produce fipronil-sulfone, which is more toxic than fipronil leading to the higher susceptibility of this species.

Production and accumulation of UV-B [ultra violet] absorbing compounds in UV-B irradiated leaves of rice, Oryza SativaL.: effects of varying UV-B doses on leaf damage, phenolic content and HPLC [high performance liquid chromatography] peak I area

International Nuclear Information System (INIS)

Caasi-Lit, M.T.

2005-01-01

The effects of varying UV-B doses on leaf damage, phenolic content and HPLC peak 1 area were studied using 65-d-old plants of the UV-B tolerant rice cultivar, M202, and the UV-B susceptible rice cultivar, Dular. Results showed that the production and accumulation of UV-B- absorbing compounds in rice leaves were affected by leaf position and levels (dose) of UV-B and time or duration of UV-B irradiation or exposure. The youngest terminal leaves showed the least damage when exposed to medium and high UV-B doses. The production of these absorptive compounds as represented by relative phenolic and HPLC peak 1 were significantly higher in younger leaves and lower in older or senescing leaves. M202 showed significantly higher amounts of peak 1 area and relative phenolic compared to UV-B susceptible rice cultivar, Dular. The results also confirmed the strong relationship of overall damage rating and area of HPLC peak 1. The development of UV-B symptoms in the susceptible cultivar was hastened when a high UV-B treatment was applied. Peak 1 area did not accumulate in the UV-B susceptible Dular at any given UV-B dose

Evidence for Non-Transmission of Rice Yellow Mottle Virus (RYMV through Rice Seed

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Sy, AA.

2004-01-01

Full Text Available An indexing of the organs (radicle and plumule and components (husk, endosperm and embryo of rice seeds using Enzyme Linked Immunosorbent Assay (ELISA was carried out to detect Rice yellow mottle virus (RYMV and establish the exact location of the virus in the rice seed. RYMV was detected only in the husk (seed coat but not in the endosperm, plumule, radicle, nor embryo. None of the seedlings raised from the seeds expressed RYMV symptoms. No virus particle was detected by the ELISA test in the leaves of the screenhouse-reared plants obtained from seeds of infected plants. The results indicate that RYMV is apparently not transmitted through rice seed probably because the virus is seed-borne in the husk (seed coat of mature rice seeds.

Phenolic characterization and variability in leaves, stems and roots of Micro-Tom and patio tomatoes, in response to nitrogen limitation.

Science.gov (United States)

Larbat, Romain; Paris, Cédric; Le Bot, Jacques; Adamowicz, Stéphane

2014-07-01

Phenolics are implicated in the defence strategies of many plant species rendering their concentration increase of putative practical interest in the field of crop protection. Little attention has been given to the nature, concentration and distribution of phenolics within vegetative organs of tomato (Solanum lycopersicum. L) as compared to fruits. In this study, we extensively characterized the phenolics in leaves, stems and roots of nine tomato cultivars using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (LC-MS(n)) and assessed the impact of low nitrogen (LN) availability on their accumulation. Thirty-one phenolics from the four sub-classes, hydroxycinnamoyl esters, flavonoids, anthocyanins and phenolamides were identified, five of which had not previously been reported in these tomato organs. A higher diversity and concentration of phenolics was found in leaves than in stems and roots. The qualitative distribution of these compounds between plant organs was similar for the nine cultivars with the exception of Micro-Tom because of its significantly higher phenolic concentrations in leaves and stems as compared to roots. With few exceptions, the influence of the LN treatment on the three organs of all cultivars was to increase the concentrations of hydroxycinnamoyl esters, flavonoids and anthocyanins and to decrease those of phenolamides. This impact of LN was greater in roots than in leaves and stems. Nitrogen nutrition thus appears as a means of modulating the concentration and composition of organ phenolics and their distribution within the whole plant. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

UV-irradiation enhances rice allelopathic potential in rhizosphere soil

DEFF Research Database (Denmark)

Mahmood, Khalid; Khan, Muhammad Bismillah; Song, Yuan Yuan

2013-01-01

Ultraviolet-B radiation is rising continuously due to stratospheric ozone depletion over temperate latitudes. This study investigated effects of UV exposure on rice allelopathic potentials. For this purpose, two rice (Oryza sativa L.) cultivars BR-41 (high allelopathic = able to inhibit neighboring...... grass and lettuce). These bioassays showed significant inhibition in lettuce and barnyard growth after UV in both rice cultivars. Interestingly, Huajingxian, which did not exhibit allelopathic potential in absence of UV showed significant inhibition after UV exposure. Phenolics, enzymes activities...... and genes responsible for biosynthesis of allelopathic compounds were examined after UV exposure. Phenolic compounds accumulated in rice leaves were quantified through HPLC analysis. They were significantly higher in BR-41 leaves after UV exposure. Enzyme activities (PAL and C4H) were significantly higher...

Selenium reduces cadmium uptake and mitigates cadmium toxicity in rice

Energy Technology Data Exchange (ETDEWEB)

Lin, Li; Zhou, Weihui; Dai, Huaxin; Cao, Fangbin; Zhang, Guoping [Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou, 310058 (China); Wu, Feibo, E-mail: wufeibo@zju.edu.cn [Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou, 310058 (China)

2012-10-15

Highlights: Black-Right-Pointing-Pointer Se alleviated Cd-toxicity, reduced Cd content and O{sub 2}{center_dot}{sup -}, H{sub 2}O{sub 2}, MDA in rice plants. Black-Right-Pointing-Pointer Se counteracted Cd-induced alterations of antioxidant enzymes. Black-Right-Pointing-Pointer Se suppressed Cd-induced increase in SOD, APX, but elevated depressed CAT activity. Black-Right-Pointing-Pointer Se markedly increased H{sup +}-ATPase, Ca{sup 2+}-ATPase activities in roots under Cd exposure. - Abstract: Hydroponic experiments were performed to investigate physiological mechanisms of selenium (Se) mitigation of Cd toxicity in rice. Exogenous Se markedly reduced Cd concentration in leaves, roots, and stems. Addition or pretreatment of 3 {mu}M Se in 50 {mu}M Cd solution significantly addressed Cd-induced growth inhibition, recovered root cell viability, and dramatically depressed O{sub 2}{center_dot}{sup -}, H{sub 2}O{sub 2}, and malondialdehyde (MDA) accumulation. Supplemental Se counteracted 50 {mu}M Cd-induced alterations of certain antioxidant enzymes, and uptake of nutrients, e.g. depressed Cd-induced increase in leaf and root superoxide dismutase (SOD) and leaf peroxidase (POD) activities, but elevated depressed catalase (CAT) activity; decreased Cd-induced high S and Cu concentrations in both leaves and roots. External Se counteracted the pattern of alterations in ATPase activities induced by Cd, e.g. significantly elevated the depressed root H{sup +}- and Ca{sup 2+}-ATPase activities, but decreased the ascent root Na{sup +}K{sup +}-ATP activity. Results indicate that alleviated Cd toxicity by Se application is related to reduced Cd uptake and ROS accumulation, balanced nutrients, and increased H{sup +}- and Ca{sup 2+}-ATPase activities in rice.

Potential nutritional and antioxidant activity of various solvent extracts from leaves and stem bark of Anisophyllea laurina R. Br ex Sabine used in folk medicine

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Gbago Onivogui

2017-07-01

Full Text Available ABSTRACT Anisophyllea laurina is a plant that has been used in folk medicine to treat malaria, dysentery, diabetes, toothache and various skin diseases. Leaves extract had protein content of 9.68% and a high calcium content of 25084.317 mg/100 g while stem bark extract was found to contain greater amounts of calcium (8560.96 mg/100 g, potassium (7649.47 mg/100 g, magnesium (1462.49 mg/100 g and iron (973.33 mg/100 g. Palmitic acid, linolenic acid, linoleic acid and oleic acid were the most abundant fatty acids in leaves and stem bark extracts. Furthermore, total phenolic (2382.39 mg GAE /100 g and total flavonoid (385.79 mg QE/100 g contents were abundant in stem bark while leaves extract was rich in total tannin content (3466.63 mg CE/100 g. However, both leaves and stem bark contained great amounts of vitamins and amino acids were a good source of antioxidant activities. For the individual polyphenol, stenophyllanin A (45.87 mg/g, casuarinin (24.55 mg/g and digalloyl-HHDP-glucopyranose isomer (15.63 mg/g were found to be the major compounds from the leaves whereas procyanidin tetramer (14.89 mg/g, (--Epicatechin (12.18 mg/g and procyanidin trimer (11.25 mg/g were the most predominant compounds from the stem bark. Additionally, the results revealed a significant and strong correlation between phenolic compounds and antioxidant activities.

Shading Contributes to the Reduction of Stem Mechanical Strength by Decreasing Cell Wall Synthesis in Japonica Rice (Oryza sativa L.

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Longmei Wu

2017-05-01

Full Text Available Low solar radiation caused by industrial development and solar dimming has become a limitation in crop production in China. It is widely accepted that low solar radiation influences many aspects of plant development, including slender, weak stems and susceptibility to lodging. However, the underlying mechanisms are not well understood. To clarify how low solar radiation affects stem mechanical strength formation and lodging resistance, the japonica rice cultivars Wuyunjing23 (lodging-resistant and W3668 (lodging-susceptible were grown under field conditions with normal light (Control and shading (the incident light was reduced by 60% with a black nylon net. The yield and yield components, plant morphological characteristics, the stem mechanical strength, cell wall components, culm microstructure, gene expression correlated with cellulose and lignin biosynthesis were measured. The results showed that shading significantly reduced grain yield attributed to reduction of spikelets per panicles and grain weight. The stem-breaking strength decreased significantly under shading treatment; consequently, resulting in higher lodging index in rice plant in both varieties, as revealed by decreased by culm diameter, culm wall thickness and increased plant height, gravity center height. Compared with control, cell wall components including non-structural carbohydrate, sucrose, cellulose, and lignin reduced quite higher. With histochemical straining, shading largely reduced lignin deposition in the sclerenchyma cells and vascular bundle cells compared with control, and decreased cellulose deposition in the parenchyma cells of culm tissue in both Wuyunjing23 and W3668. And under shading condition, gene expression involved in secondary cell wall synthesis, OsPAL, OsCOMT, OsCCoAOMT, OsCCR, and OsCAD2, and primary cell wall synthesis, OsCesA1, OsCesA3, and OsCesA8 were decreased significantly. These results suggest that gene expression involved in the reduction of

Shading Contributes to the Reduction of Stem Mechanical Strength by Decreasing Cell Wall Synthesis in Japonica Rice (Oryza sativa L.).

Science.gov (United States)

Wu, Longmei; Zhang, Wujun; Ding, Yanfeng; Zhang, Jianwei; Cambula, Elidio D; Weng, Fei; Liu, Zhenghui; Ding, Chengqiang; Tang, She; Chen, Lin; Wang, Shaohua; Li, Ganghua

2017-01-01

Low solar radiation caused by industrial development and solar dimming has become a limitation in crop production in China. It is widely accepted that low solar radiation influences many aspects of plant development, including slender, weak stems and susceptibility to lodging. However, the underlying mechanisms are not well understood. To clarify how low solar radiation affects stem mechanical strength formation and lodging resistance, the japonica rice cultivars Wuyunjing23 (lodging-resistant) and W3668 (lodging-susceptible) were grown under field conditions with normal light (Control) and shading (the incident light was reduced by 60%) with a black nylon net. The yield and yield components, plant morphological characteristics, the stem mechanical strength, cell wall components, culm microstructure, gene expression correlated with cellulose and lignin biosynthesis were measured. The results showed that shading significantly reduced grain yield attributed to reduction of spikelets per panicles and grain weight. The stem-breaking strength decreased significantly under shading treatment; consequently, resulting in higher lodging index in rice plant in both varieties, as revealed by decreased by culm diameter, culm wall thickness and increased plant height, gravity center height. Compared with control, cell wall components including non-structural carbohydrate, sucrose, cellulose, and lignin reduced quite higher. With histochemical straining, shading largely reduced lignin deposition in the sclerenchyma cells and vascular bundle cells compared with control, and decreased cellulose deposition in the parenchyma cells of culm tissue in both Wuyunjing23 and W3668. And under shading condition, gene expression involved in secondary cell wall synthesis, OsPAL, OsCOMT, OsCCoAOMT, OsCCR , and OsCAD2 , and primary cell wall synthesis, OsCesA1, OsCesA3 , and OsCesA8 were decreased significantly. These results suggest that gene expression involved in the reduction of lignin and

Changes of organic acid exudation and rhizosphere pH in rice plants under chromium stress

International Nuclear Information System (INIS)

Zeng Fanrong; Chen Song; Miao Ying; Wu Feibo; Zhang Guoping

2008-01-01

The effect of chromium (Cr) stress on the changes of rhizosphere pH, organic acid exudation, and Cr accumulation in plants was studied using two rice genotypes differing in grain Cr accumulation. The results showed that rhizosphere pH increased with increasing level of Cr in the culture solution and with an extended time of Cr exposure. Among the six organic acids examined in this experiment, oxalic and malic acid contents were relatively higher, and had a significant positive correlation with the rhizosphere pH, indicating that they play an important role in changing rhizosphere pH. The Cr content in roots was significantly higher than that in stems and leaves. Cr accumulation in plants was significantly and positively correlated with rhizosphere pH, and the exudation of oxalic, malic and citric acids, suggesting that an increase in rhizosphere pH, and exudation of oxalic, malic and citric acid enhances Cr accumulation in rice plants. - Rhizosphere pH and organic acid exudation of rice roots are markedly affected by chromium level in culture solution

Comparative Study on Characteristics and Potential of Rice Straws and Dry Leaves as a Binder in Refuse Derived Fuel (RDF)

International Nuclear Information System (INIS)

Zulhafizal Othman; Lias, K.; Hashim, N.H.; Clement, F.N.

2013-01-01

Integrated waste management systems are one of the greatest challenges in order to develop the green environment. In this research, two types of binder were chosen in producing of Refuse Derived Fuel (RDF) which is rice straws and dry leaves. The objective of the research is to identify which types of binder that can give the optimum performance. This two binder was mixed with paper and plastic waste with controlled mixing ratio which is 3:1 (ratio 1), 3:1.5(ratio 2) and 3:2 (ratio 3). In order to identify the optimum ratio of RDF, 45 number of samples was prepared and their properties such as moisture content, carbon content, sulfur content, chlorine content and calorific value were evaluated. Result indicated that samples with rice straw as a binder give the optimum result with the ratio of 3:1. The optimum values of the carbon content is 50.9 %, moisture content is 5.5 %, chlorine content is 0.0 %, sulfur content is 2.1 % and calorific value is 29.0 MJ/ kg. Hence, rice straws shows a great potential to be used as binder in production of RDF. (author)

Antixenosis and Antibiosis Resistance in Rice Cultivars against Chilo suppressalis (Walker) (Lepidoptera: Crambidae).

Science.gov (United States)

Tabari, M A; Fathi, S A A; Nouri-Ganbalani, G; Moumeni, A; Razmjou, J

2017-08-01

The striped stem borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae), is an important pest afflicting rice in most rice-growing countries in the world. Deliniating the categories of resistance in rice genotypes under field conditions could be helpful in managment of this pest. Two categories of resistance, antixenosis and antibiosis, were examined in ten popular and diverse rice genotypes of different origin that had been selected for their resistance to the striped stem borer in a previous study. Significant differences were found between genotypes for the number of egg masses, number of eggs, preference index, larval and pupal weight, larval development time, larval survival rate, larval mine length, and leaf trichome density. It was found that the rice genotypes Novator, A7801, and Nemat had the more pronounced antixenosis-type resistance, whereas AB1 and Shirodi had better antiobiosis-type resistance. Interestingly, the rice genotype AN-74 for which Nemat is the parental line showed both types of resistance and could be effectively used in an integrated pest management of the rice striped stem borer.

Toxicological evaluation of an aqueous suspension from leaves and stems of Petiveria alliacea L. (Phytolaccaceae).

Science.gov (United States)

García-Pérez, Martha-Estrella; Alfonso-Castillo, Alfredo; Lores, Onel Fong; Batista-Duharte, Alexander; Lemus-Rodríguez, Zoe

2018-01-30

Petiveria alliacea L. (Phytolaccaceae) is used in folk medicine due to its antispasmodic, diuretic, hypoglycemic, abortive, anti-inflammatory and anticancerogenic properties. Although P. alliacea is considered toxic by people, its toxicity remains a concern since it is strongly dependent on the extraction method and the part of the plant used during tests. Even if some healers prefer to use the aerial parts in a liquefied form or by chewing them, instead of decoctions or infusions, no toxicological studies exist using whole dried stems and leaves. The toxicity of a suspension of the powder from the leaves and stems of P. alliacea was assessed in Sprague Dawley rats by oral administration using two tests: 1) the acute toxic class method, which allows classification of substances according to their intrinsic toxicity and 2) the repeated dose 28-day method, following the guidelines 423 and 407 respectively from the Organization for the Economic Cooperation and Development. Chemical characterization of this powder was performed by GC-MS, UV-fluorescence, proximate and elemental analysis. P. alliacea powder from stems and leaves was classed in the hazard category 5 (LD 50 > 2000mg/kg) according to the acute toxicology study. There were no toxicity signs at 1000mg/kg in the repeated dose study, although higher values of total leukocytes were found in the satellite and males of the experimental group, which were attributed to the immunomodulatory properties of this plant. According to GC-MS, the prevailing compounds identified were phytol, (R)-(-)-(Z)-14-methyl-8-hexadecen-1-ol, 1-(2-hydrohyethyl)-1,2,4-triazole and methyl β-dimethylaminoisobutyrate. In conclusion, the oral administration of the P. alliacea powder to Sprague Dawley rats did not result in deaths and was not associated with adverse effects reflected in the general condition, body weights or histopathological abnormalities. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison study of moisture content, colour properties and essential oil compounds extracted by hydrodistillation and supercritical fluid extraction between stem and leaves of lemongrass (Cymbopogun citratus)

Science.gov (United States)

Kamaruddin, Shazlin; Mustapha, Wan Aida Wan; Haiyee, Zaibunnisa Abdul

2018-04-01

The objectives of this study were to compare the properties of moisture content, colour and essential oil compounds between stem and leaves of lemongrass (Cymbopogun citratus). The essential oil was extracted using two different methods which are hydrodistillation and supercritical fluid extraction (SFE). There was no significant difference of moisture content between stem and leaves of lemongrass. The lightness (L) and yellowness (+b) values of the stems were significantly higher (pleaves. The highest yield of essential oil was obtained by extraction using supercritical fluid extraction (SFE) in leaves (˜ 0.7%) by treatment at 1700psi and 50°C. The main compound of extracted essential oil was citral (geranial and neral).

Methyl jasmonate induced resistance in cheniere rice and soybean plants

Science.gov (United States)

Taplin, C.

2017-12-01

Methyl jasmonate (MJ) is a compound naturally occurring in certain plants that aids in plant defense. In this study, we examined the difference in herbivory of fall armyworm (FAW) on control plants (treated without MJ) and MJ-treated plants. Seeds of cheniere rice and soybean were soaked in MJ overnight and planted in the greenhouse, although the soybean never grew. Therefore, only the mature plant leaves of cheniere rice were fed to FAW and the difference in herbivory was looked at. Our results show there is no statistical difference in the herbivory of the cheniere rice plant leaves.

Multiple Biological Effects of Olive Oil By-products such as Leaves, Stems, Flowers, Olive Milled Waste, Fruit Pulp, and Seeds of the Olive Plant on Skin.

Science.gov (United States)

Kishikawa, Asuka; Ashour, Ahmed; Zhu, Qinchang; Yasuda, Midori; Ishikawa, Hiroya; Shimizu, Kuniyoshi

2015-06-01

As olive oil production increases, so does the amount of olive oil by-products, which can cause environmental problems. Thus, new ways to utilize the by-products are needed. In the present study, five bioactive characteristics of olive oil by-products were assessed, namely their antioxidant, anti-bacterial, anti-melanogenesis, anti-allergic, and collagen-production-promoting activities. First, the extracts of leaves (May and October), stems (May and October), flowers, olive milled waste, fruit pulp and seeds were prepared using two safe solvents, ethanol and water. According to HPLC and LC/MS analysis and Folin-Ciocalteu assay, the ethanol extracts of the leaves (May and October), stems (May and October) and flowers contained oleuropein, and the ethanol extract of the stems showed the highest total phenol content. Oleuropein may contribute to the antioxidant and anti-melanogenesis activities of the leaves, stems, and flowers. However, other active compounds or synergistic effects present in the ethanol extracts are also likely to contribute to the anti-bacterial activity of the leaves and flowers, the anti-melanogenesis activity of some parts, the anti-allergic activity of olive milled waste, and the collagen-production-promoting activity of the leaves, stems, olive milled waste and fruit pulp. This study provides evidence that the by-products of olive oil have the potential to be further developed and used in the skin care industry. Copyright © 2015 John Wiley & Sons, Ltd.

Modeling the leaf angle dynamics in rice plant.

Directory of Open Access Journals (Sweden)

Yonghui Zhang

Full Text Available The leaf angle between stem and sheath (SSA is an important rice morphological trait. The objective of this study was to develop and validate a dynamic SSA model under different nitrogen (N rates for selected rice cultivars. The time-course data of SSA were collected in three years, and a dynamic SSA model was developed for different main stem leaf ranks under different N rates for two selected rice cultivars. SSA increased with tiller age. The SSA of the same leaf rank increased with increase in N rate. The maximum SSA increased with leaf rank from the first to the third leaf, then decreased from the third to the final leaf. The relationship between the maximum SSA and leaf rank on main stem could be described with a linear piecewise function. The change of SSA with thermal time (TT was described by a logistic equation. A variety parameter (the maximum SSA of the 3rd leaf on main stem and a nitrogen factor were introduced to quantify the effect of cultivar and N rate on SSA. The model was validated against data collected from both pot and field experiments. The relative root mean square error (RRMSE was 11.56% and 14.05%, respectively. The resulting models could be used for virtual rice plant modeling and plant-type design.

Access and Definition: Exploring how STEM Faculty, Department Heads, and University Policy Administrators Navigate the Implementation of a Parental Leave Policy

OpenAIRE

Schimpf, Corey T; Santiago, Marisol Mercado; Pawley, Alice L.

2012-01-01

Access and Definition: Exploring how STEM Faculty, Department Heads and University Policy Administrators Navigate the Enactment of a Parental Leave Policy A key feature in various reports exploring women’s persisting underrepresentation in STEM faculty positions in the US is the need to disseminate policy information to all stakeholders involved in issues relating to women STEM faculty underrepresentation and retention. Indeed, the National Academies of Science Beyond Barriers and Bias: Fulfi...

Utilizing Bacillus to inhibit the growth and infection by sheath blight pathogen, Rhizoctoniasolani in rice

Science.gov (United States)

Margani, R.; Hadiwiyono; Widadi, S.

2018-03-01

Rhizoctonia solani Kuhn is a common pathogen of rice. The pathogen causes sheath blight of rice. The pathogen can cause loss in the production of rice up to 45%. So far, the disease however is still poorly taken care of by the farmers and researchers, so the control measures is nearly never practiced by the farmers in the fields. It due to the unavailability of effective control method of the disease. Therefore, development to control the disease is important. Bacillus is one of popular bacteria which is effective as biological control agent of a lot of pathogens in plants, but it has not been used for control sheath blight in rice yet. The current researches were aimed to study the potential of Bacillus collected from healthy rice as candidates of biological control agent of the disease. The results showed that some isolates showed indications to inhibit significantly the growth and infection of the pathogen. We obtained at least five isolates of Bacillus collected from leaves, sheath, and stem of healthy rice fields. All of the isolates could effectively inhibit the growth of R. solani in vitro on potato dextrose medium at range 30.33-58.00%, whereas in vivo B05 isolate was the most effective in inhibiting the infection of pathogen at 30.43%. It was not significantly different (P≥0.05) to application of hexaconazol with dosage of 2 ml L-1.

RFLP-facilitated investigation of the quantitative resistance of rice to brown planthopper ( Nilaparvata lugens).

Science.gov (United States)

Xu, X. F.; Mei, H. W.; Luo, L. J.; Cheng, X. N.; Li, Z. K.

2002-02-01

Quantitative trait loci (QTLs), conferring quantitative resistance to rice brown planthopper (BPH), were investigated using 160 F(11) recombinant inbred lines (RILs) from the Lemont/Teqing cross, a complete RFLP map, and replicated phenotyping of seedbox inoculation. The paternal indica parent, Teqing, was more-resistant to BPH than the maternal japonica parent, Lemont. The RILs showed transgressive segregation for resistance to BPH. Seven main-effect QTLs and many epistatic QTL pairs were identified and mapped on the 12 rice chromosomes. Collectively, the main-effect and epistatic QTLs accounted for over 70% of the total variation in damage scores. Teqing has the resistance allele at four main-effect QTLs, and the Lemont allele resulted in resistance at the other three. Of the main-effect QTLs identified, QBphr5b was mapped to the vicinity of gl1, a major gene controlling leaf and stem pubescence. The Teqing allele controlling leaf and stem pubescence was associated with resistance, while the Lemont allele for glabrous stem and leaves was associated with susceptibility, indicating that this gene may have contributed to resistance through antixenosis. Similar to the reported BPH resistance genes, the other six detected main-effect QTLs were all mapped to regions where major disease resistance genes locate, suggesting they might have contributed either to antibiosis or tolerance. Our results indicated that marker-aided pyramiding of major resistance genes and QTLs should provide effective and stable control over this devastating pest.

Fast Detection of Striped Stem-Borer (Chilo suppressalis Walker Infested Rice Seedling Based on Visible/Near-Infrared Hyperspectral Imaging System

Directory of Open Access Journals (Sweden)

Yangyang Fan

2017-10-01

Full Text Available Striped stem-borer (SSB infestation is one of the most serious sources of damage to rice growth. A rapid and non-destructive method of early SSB detection is essential for rice-growth protection. In this study, hyperspectral imaging combined with chemometrics was used to detect early SSB infestation in rice and identify the degree of infestation (DI. Visible/near-infrared hyperspectral images (in the spectral range of 380 nm to 1030 nm were taken of the healthy rice plants and infested rice plants by SSB for 2, 4, 6, 8 and 10 days. A total of 17 characteristic wavelengths were selected from the spectral data extracted from the hyperspectral images by the successive projection algorithm (SPA. Principal component analysis (PCA was applied to the hyperspectral images, and 16 textural features based on the gray-level co-occurrence matrix (GLCM were extracted from the first two principal component (PC images. A back-propagation neural network (BPNN was used to establish infestation degree evaluation models based on full spectra, characteristic wavelengths, textural features and features fusion, respectively. BPNN models based on a fusion of characteristic wavelengths and textural features achieved the best performance, with classification accuracy of calibration and prediction sets over 95%. The accuracy of each infestation degree was satisfactory, and the accuracy of rice samples infested for 2 days was slightly low. In all, this study indicated the feasibility of hyperspectral imaging techniques to detect early SSB infestation and identify degrees of infestation.

Mechanisms of Fe biofortification and mitigation of Cd accumulation in rice (Oryza sativa L.) grown hydroponically with Fe chelate fertilization.

Science.gov (United States)

Chen, Zhe; Tang, Ye-Tao; Zhou, Can; Xie, Shu-Ting; Xiao, Shi; Baker, Alan J M; Qiu, Rong-Liang

2017-05-01

Cadmium contaminated rice from China has become a global food safety issue. Some research has suggested that chelate addition to substrates can affect metal speciation and plant metal content. We investigated the mitigation of Cd accumulation in hydroponically-grown rice supplied with EDTANa 2 Fe(II) or EDDHAFe(III). A japonica rice variety (Nipponbare) was grown in modified Kimura B solution containing three concentrations (0, 10, 100 μΜ) of the iron chelates EDTANa 2 Fe(II) or EDDHAFe(III) and 1 μΜ Cd. Metal speciation in solution was simulated by Geochem-EZ; growth and photosynthetic efficiency of rice were evaluated, and accumulation of Cd and Fe in plant parts was determined. Net Cd fluxes in the meristematic zone, growth zone, and maturation zone of roots were monitored by a non-invasive micro-test technology. Expression of Fe- and Cd-related genes in Fe-sufficient or Fe-deficient roots and leaves were studied by QRT-PCR. Compared to Fe deficiency, a sufficient or excess supply of Fe chelates significantly enhanced rice growth by elevating photosynthetic efficiency. Both Fe chelates increased the Fe content and decreased the Cd content of rice organs, except for the Cd content of roots treated with excess EDDHAFe(III). Compared to EDDHAFe(III), EDTANa 2 Fe(II) exhibited better mitigation of Cd accumulation in rice by generating the EDTANa 2 Cd complex in solution, decreasing net Cd influx and increasing net Cd efflux in root micro-zones. Application of EDTANa 2 Fe(II) and EDDHAFe(III) also reduced Cd accumulation in rice by inhibiting expression of genes involved in transport of Fe and Cd in the xylem and phloem. The 'win-win' situation of Fe biofortification and Cd mitigation in rice was achieved by application of Fe chelates. Root-to-stem xylem transport of Cd and redistribution of Cd in leaves by phloem transport can be regulated in rice through the use of Fe chelates that influence Fe availability and Fe-related gene expression. Fe fertilization

Uptake, translocation and transformation of antimony in rice (Oryza sativa L.) seedlings.

Science.gov (United States)

Cai, Fei; Ren, Jinghua; Tao, Shu; Wang, Xilong

2016-02-01

Antimony (Sb), as a toxic metalloid, has been gaining increasing research concerns due mainly to its severe pollution in many places. Rice has been identified to be the dominant intake route of Sb by residents close to the Sb mining areas. A hydroponic experiment was conducted to investigate the difference in uptake, translocation and transformation of Sb in rice seedlings of four cultivars exposed to 0.2 or 1.0 mg/L of Sb(V). The results showed that mass concentration of iron plaque (mg/kg FW) formed at the root surfaces of cultivar N was the highest among all tested cultivars at both low and high exposure levels of Sb(V). The accumulated Sb concentration in iron plaque significantly increased with an increase in mass concentration of iron plaque formed at the rice root. The total amount of iron plaque (mg/pot) at rice root generally increased with increasing exposed Sb(V) concentration, which was closely associated with the increasing lipid peroxidation in roots. Concentration percentage of Sb in rice root significantly reduced as the corresponding value in the iron plaque increased, suggesting that iron plaque formation strongly suppressed uptake of Sb by rice root. Sb concentration in rice tissues followed an order: root > stem, leaf. The japonica rice (cultivars N and Z) exhibited a stronger translocation tendency of Sb from root to stem than indica hybrid rice (cultivars F and G). Translocation of Sb from root of cultivar F to its stem and leaf was sharply enhanced with increasing Sb exposure concentration. Sb(V) could be reduced to Sb(III) in rice tissues, especially in stems (10-26% of the total Sb). For the sake of food safety, the difference in uptake, translocation and transformation of Sb in rice species planted in Sb-contaminated soils should be taken into consideration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization, Purification, and Starch Stain Wash Application of Two New α-Amylases Extracted from Leaves and Stems of Pergularia tomentosa

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Imen Lahmar

2017-01-01

Full Text Available A continuous research is attempted to fulfil the highest industrial demands of natural amylases presenting special properties. New α-amylases extracted from stems and leaves of Pergularia tomentosa, which is widespread and growing spontaneously in Tunisia, were studied by the means of their activities optimization and purification. Some similarities were recorded for the two identified enzymes: (i the highest amylase activity showed a promoted thermal stability at 50°C; (ii the starch substrate at 1% enhanced the enzyme activity; (iii the two α-amylases seem to be calcium-independent; (iv Zn2+, Cu2+, and Ag2+ were considered as important inhibitors of the enzyme activity. Following the increased gradient of elution on Mono Q-Sepharose column, an increase in the specific activity of 11.82-fold and 10.92-fold was recorded, respectively, for leaves and stems with the presence of different peaks on the purification profiles. Pergularia amylases activities were stable and compatible with the tested commercial detergents. The combination of plant amylase and detergent allowed us to enhance the wash performance with an increase of 35.24 and 42.56%, respectively, for stems and leaves amylases. Characterized amylases were reported to have a promoted potential for their implication notably in detergent industry as well as biotechnological sector.

Chromatographic fingerprinting and free-radical scavenging activity of ethanol extracts of Muntingia calabura L. leaves and stems

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William Patrick Cruiz Buhian

2017-02-01

Conclusions: M. calabura exhibited very high antioxidant activity in its leaves and stems ethanol extracts, both of which are used in traditional medicine. The TLC results demonstrated the presence of diverse secondary metabolites in the leaf and stem ethanol extracts, indicating that the antioxidant activity, including other bioactivities may be attributed to these phytochemical constituents. This paper has reported for the first time the TLC fingerprinting of M. calabura using visible light, UV 254 nm, UV 366 and post-derivatization with vanillin-spray to visualize separate spots on TLC plates.

Uptake, translocation and transformation of antimony in rice (Oryza sativa L.) seedlings

International Nuclear Information System (INIS)

Cai, Fei; Ren, Jinghua; Tao, Shu; Wang, Xilong

2016-01-01

Antimony (Sb), as a toxic metalloid, has been gaining increasing research concerns due mainly to its severe pollution in many places. Rice has been identified to be the dominant intake route of Sb by residents close to the Sb mining areas. A hydroponic experiment was conducted to investigate the difference in uptake, translocation and transformation of Sb in rice seedlings of four cultivars exposed to 0.2 or 1.0 mg/L of Sb(V). The results showed that mass concentration of iron plaque (mg/kg FW) formed at the root surfaces of cultivar N was the highest among all tested cultivars at both low and high exposure levels of Sb(V). The accumulated Sb concentration in iron plaque significantly increased with an increase in mass concentration of iron plaque formed at the rice root. The total amount of iron plaque (mg/pot) at rice root generally increased with increasing exposed Sb(V) concentration, which was closely associated with the increasing lipid peroxidation in roots. Concentration percentage of Sb in rice root significantly reduced as the corresponding value in the iron plaque increased, suggesting that iron plaque formation strongly suppressed uptake of Sb by rice root. Sb concentration in rice tissues followed an order: root > stem, leaf. The japonica rice (cultivars N and Z) exhibited a stronger translocation tendency of Sb from root to stem than indica hybrid rice (cultivars F and G). Translocation of Sb from root of cultivar F to its stem and leaf was sharply enhanced with increasing Sb exposure concentration. Sb(V) could be reduced to Sb(III) in rice tissues, especially in stems (10–26% of the total Sb). For the sake of food safety, the difference in uptake, translocation and transformation of Sb in rice species planted in Sb-contaminated soils should be taken into consideration. - Highlights: • Sb(V) caused lipid peroxidation and increased iron plaque formation at root surface. • The iron plaque may suppress uptake of Sb by rice. • Cultivars

Assessment of total soil and plant trace elements in rice-based production systems in NE Italy

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Bini, Claudio; Nadimi-Goki, Mandana; Kato, Yoichi; Vianello, Gilmo; Vittori, Livia; Wahsha, Mohammad; Spiandorello, Massimo

2014-05-01

Macro- and micronutrients concentrations, and PTEs contents in soils and plants (rice) from the rice district in the Venetian territory (NE Italy) have been determined by ICP-MS spectrometry, with the following aims: - to determine the background levels of macro- and microelements in the study area; - to assess possible contamination of soils and plants; - to calculate the Translocation Factor (TF) of metals from soil to plant, and the possible hazard for human health. Four rice plots with different rotation systems were investigated from seedling time to harvesting; sampling of soils (0-30cm) and plants was carried out 4 times during growing season (three replicates). Rice plants were separated into roots, stems, leaves and grains, and then oven-dried. Chemical and physical analyses were carried out at the Soil Science Lab of the University of Bologna and Venice, respectively. The results obtained point to a land with moderate soil contamination by trace elements (namely Li, Sn, Tl, Sr, Ti, Fe). Heavy metal (Sb, As, Be, Cd, Co, Cr, Ni, Pb, Cu, V, Zn ) concentrations in soils are below the threshold indicated by the Italian legislation (DM 152/2006). Cd, Sn, and Ti contents in soils are positively correlated with soil pH, while As, Fe, Li, Ti, Tl and Zn are negatively correlated with organic matter content. With the exception of Strontium, soil metal contents are always correlated between variable couples. HMs in plants vary according to the sampling season, texture and moisture, and soil pH. Most non-essential trace elements are accumulated in rice roots and, only in cases of essential micronutrients, in leaves. Therefore, rice can be assumed as an accumulator plant of As, Pb, Cr, Ba, and Ti, whereas it is as an indicator plant for Cu, Fe, Ni, Mn and Zn. The results of multiple linear regression analysis showed that soil pH has a larger effect on Ba, Cr, Cu, Fe, Mn, Ni, Ti and Zn concentrations in grain than other soil parameters. The average translocation of

[Effects of fish on field resource utilization and rice growth in rice-fish coculture].

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Zhang, Jian; Hu, Liang Liang; Ren, Wei Zheng; Guo, Liang; Wu, Min Fang; Tang, Jian Jun; Chen, Xin

2017-01-01

Rice field can provide habitat for fish and other aquatic animals. Rice-fish coculture can increase rice yield and simultaneously reduce the use of chemicals through reducing rice pest occurrence and nutrient complementary use. However, how fish uses food sources (e.g. phytoplankton, weeds, duckweed, macro-algal and snail) from rice field, and whether the nutrients releasing from those food sources due to fish transforming can improve rice growth are still unknown. Here, we conducted two field experiments to address these questions. One was to investigate the pattern of fish activity in the field using the method of video recording. The other was to examine the utilization of field resources by fish using stable isotope technology. Rice growth and rice yield were also exa-mined. Results showed that fish tended to be more active and significantly expanded the activity range in the rice-fish coculture compared to fish monoculture (fish not living together with rice plants). The contributions of 3 potential aquatic organisms (duckweed, phytoplankton and snail) to fish dietary were 22.7%, 34.8% and 30.0% respectively under rice-fish coculture without feed. Under the treatment with feed, however, the contributions of these 3 aquatic organisms to the fish die-tary were 8.9%, 5.9% and 1.6% respectively. The feed contribution was 71.0%. Rice-fish coculture significantly increased the nitrogen concentration in rice leaves, prolonged tillering stage by 10-12 days and increased rice spike rate and yield. The results suggested that raising fish in paddy field may transform the nutrients contained in field resources to bioavailable for rice plants through fish feeding activity, which can improve rice growth and rice yield.

Morphological Variation of Six Pigmented Rice Local Varieties Grown in Organic Rice Field in Sengguruh Village, Kepanjen District, Malang Regency

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Shinta

2014-05-01

Full Text Available Indonesia is the third richest country for pigmented rice source such as Wojalaka black rice of East Nusa Tenggara (NTT, Manggarai of NTT, Toraja of South Sulawesi, Cempo Ireng of Central Java and red rice of Aek Sibundong (leading variety and Baubau of Southeast Sulawesi. However, the morphological character of pigmented rice in Indonesia is less reported. The objective of research was to compare the morphological variation of root, stem, leaf, panicle, floret and the colour of milk mature grain and mature grain by observing the vegetative and generative parts of six local rice varieties. Research had been conducted from February 2012 to February 2014 in Sengguruh Village, Kepanjen District, Malang Regency. This study type was quasi-experiment with eleven replications. Group Random Design was used. The observation was given upon vegetative, reproductive and maturity phases as groups. Independent variables in this study were six rice varieties, while the dependent variable was morphological variation (root, stem, leaf, panicle, floret, milk mature grain and mature grain. The analysis of multivariate data in cluster and bip lot was carried out with PAST. The result of the study indicated that there was morphological difference on stem, leaf, panicle, floret, milk mature grain and mature grain. The colour of the stem in Aek Sibundong variety was purple, while that of other varieties was green. Toraja and Manggarai varieties had the highest height with 163-168 cm, followed by Cempo Ireng with 139 cm, Wojalaka and Baubau with 110-112 cm. Aek Sibundong Variety had the lowest height with 99 cm. Aek Sibundong and Wojalaka varieties had 6-7 internodes which were the greatest number of internode, while other varieties only had 4-5 internodes. Some varieties, such as Aek Sibundong, Wojalaka and Baubau had short and small leaf. The leaflet angle of Aek Sibundong and Baubau were 14o and it might be said as upright, while that of Wojalaka was 43o or moderate

Chemical composition of fatty acid and unsaponifiable fractions of leaves, stems and roots of Arbutus unedo and in vitro antimicrobial activity of unsaponifiable extracts.

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Diba, Mohamed Amine; Paolini, Julien; Bendahou, Mourad; Varesi, Laurent; Allali, Hocine; Desjobert, Jean-Marie; Tabti, Boufeldja; Costa, Jean

2010-07-01

The chemical composition of the fatty acid and unsaponifiable fractions of the leaves, stems and roots of Arbutus unedo L. were determined using gas chromatography and gas chromatography-mass spectrometry. The fatty acid fractions of the leaves, stems and roots contained 38.5%, 31.3% and 14.1% palmitic acid, respectively, along with other long-chain fatty acids (up to C22). The chemical composition of the unsaponifiable fractions differed: the leaf and stem fractions contained high levels of aliphatic (32.1% and 62.6%, respectively) and terpenic compounds (49.6% and 25.7%, respectively), and the root fraction mainly contained esters, of which the most abundant was benzyl cinnamate (36.6%). The antimicrobial activities of the unsaponifiable fractions against nine species of microorganisms were assessed. The unsaponifiable leaf and stem extracts inhibited the growth of Klebsiella pneumoniae, Enterococcus faecalis and Candida albicans.

The Cellulolytic Activity And Volatile Fatty Acid Product Of Rumen Bacteria Of Buffalo And Cattle On Rice Straw, Elephant Grass, and Sesbania Leaves Substrates

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Caribu Hadi Prayitno

1999-01-01

Full Text Available Experiment on The Cellulolytic Activity and Volatile Fatty Acid Product of Rumen Bacteria of Buffalo and Cattle on Rice Straw, Elephant Grass, and Sesbania Leaves Substrates had been conducted at Feedstuff Laboratory of Animal Science Soedirman University. The basic design  that was used in this experiment was Completely Randomized Design (CRD with factorial pattern of 6 x 3, three replications. The bacteria isolate as the factors were cellulolytic rumen bacteria isolate of buffalo (A1, A2, and A3 and cattle (A4, A5 and A6 while the substrates (second factor  were NDF rice straw (S1, elephant grass (S2, and sesbania leaves (S3 Cell walls. The result of this experiment showed that the interaction between bacteria isolate and substrate  type were significant on pH, NDF digestibility, cellulase activity, pH was  6.28 until 6.43.  The NDF digestibility range was 12.27 until 55.61 percent. The lowers of cellulase activity was 5.11 IU/ml and the higher was 24.47 IU/ml. The range of acetic acid yield was 63.37 to 307.467 mg/100 ml. Range of  propionic production was 15.17 to 352.20 mg/ 100 ml. The production of butiric acid was 8.77 to 40.87 mg/ 100 ml. The cellulase activity  of cellulolytic rumen bacteria of buffalo was higher than cattle, and also their effect on NDF digestibility of rice straw, elephant grass, and sesbania leaves cell walls. The A3 of cellulolytic rumen bacteria isolate of  buffalo changed cell walls substrat to volatile fatty  acid was more effective than cattle, especially on cell elephant grass. Propionic and butiric  acid that was produced by cellulolytic rumen bacteria isolate of buffalo more higher than cattle (Animal Production 1 (1 : 1-9 (1999 Key Words: Cellulolytic, VFA, Rumen Bacteria, Buffalo, Cattle.

Evaluating the non-rice host plant species of Sesamia inferens (Lepidoptera: Noctuidae) as natural refuges: resistance management of Bt rice.

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Liu, Zhuorong; Gao, Yulin; Luo, Ju; Lai, Fengxiang; Li, Yunhe; Fu, Qiang; Peng, Yufa

2011-06-01

Although rice (Oryza sativa L.) lines that express Bacillus thuringiensis (Bt) toxins have shown great potential for managing the major Lepidoptera pests of rice in southern China, including Sesamia inferens, their long-term use is dependent on managing resistance development to Bt toxins in pest populations. The maintenance of "natural" refuges, non-Bt expressing plants that are hosts for a target pest, has been proposed as a means to minimize the evolution of resistance to Bt toxins in transgenic plants. In the current study, field surveys and greenhouse experiments were conducted to identify host plants of S. inferens that could serve as "natural" refuges in rice growing areas of southern China. A field survey showed that 34 plant species in four families can be alternative host plants of S. inferens. Based on injury level under field conditions, rice (Oryza sativa L.); water oat (Zizania latifolia Griseb.); corn (Zea mays L.); tidalmarsh flatsedge (Cyperus serotinus Rottb.); and narrow-leaved cat-tail (Typha angustifolia Linn.) were identified as the primary host plant species of S. inferens. Greenhouse experiments further demonstrated that water oat, corn, and narrow-leaved cat-tail could support the survival and development of S. inferens. Interestingly, greenhouse experiments showed that S. inferens preferred to lay eggs on tidalmarsh flatsedge compared with the other three nonrice host species, although no pupae were found in the plants examined in field surveys. Few larvae were found to survive on tidalmarsh flatsedge in greenhouse bioassays, suggesting that tidalmarsh flatsedge could serve as a "dead-end" trap crop for S. inferens, but is not a candidate to serve as natural refuge to maintain susceptible S. inferens. Overall, these results suggest that water-oat, corn, and narrow-leaved cat-tail might serve as "natural refuge" for S. inferens in rice planting area of southern China when Bt rice varieties are planted.

Analysis of Rhizome Development in Oryza longistaminata, a Wild Rice Species.

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Yoshida, Akiko; Terada, Yasuhiko; Toriba, Taiyo; Kose, Katsumi; Ashikari, Motoyuki; Kyozuka, Junko

2016-10-01

Vegetative reproduction is a form of asexual propagation in plants. A wide range of plants develop rhizomes, modified stems that grow underground horizontally, as a means of vegetative reproduction. In rhizomatous species, despite their distinct developmental patterns, both rhizomes and aerial shoots derive from axillary buds. Therefore, it is of interest to understand the basis of rhizome initiation and development. Oryza longistaminata, a wild rice species, develops rhizomes. We analyzed bud initiation and growth of O. longistaminata rhizomes using various methods of morphological observation. We show that, unlike aerial shoot buds that contain a few leaves only, rhizome buds initiate several leaves and bend to grow at right angles to the original rhizome. Rhizomes are maintained in the juvenile phase irrespective of the developmental phase of the aerial shoot. Stem elongation and reproductive transition are tightly linked in the aerial shoots, but are uncoupled in the rhizome. Our findings indicate that developmental programs operate independently in the rhizomes and aerial shoots. Temporal modification of the developmental pathways that are common to rhizomes and aerial shoots may be the source of developmental plasticity. Furthermore, the creation of new developmental systems appears to be necessary for rhizome development. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Root-to-shoot signal transduction in rice under salt stress

International Nuclear Information System (INIS)

Bano, A.

2010-01-01

This paper describes the impact of salt stress on changes in the level of Abscisic acid (ABA) and cytokinins as signal molecules communicated through root-to-shoot in rice. The study focus to investigate the time related changes in the salt induced ABA and cytokinins accumulation concomitant with the changes in water potential and stomatal conductance of salt stressed plants. Seeds of 3 rice varieties were grown in plastic pots in phytotron. The changes in the level of abscisic acid (ABA), transzeatin riboside (t-zr) and 2-isopentyl adenine (2-ipa) were monitored in xylem sap and leaves of three rice varieties viz. BAS-385 (salt-sensitive), BG-402 (moderately tolerant) and NIAB-6 (tolerant). The salt solution (NaCl,1.2 dS m-1) was added to the rooting medium after transplanting when plants were 50 d old. There was delay in response of stomata to salt treatment in BAS-385 as opposed to earlier increase in leaf resistance in BG-402 and NIAB-6. The stem water potential increased sharply in all the varieties following salt treatment but the decrease in stomatal conductance of leaves preceded the decrease in stem water potential. The concentration of xylem ABA increased significantly greatly reaching a peak in BAS-385 much earlier (24 h of salt treatment) than that of other varieties. The ABA accumulation was delayed and the magnitude of ABA accumulation was greater in BG-402 and NIAB-6.The xylem flux of ABA followed a similar pattern. The concentration of xylem t-zr showed a short- term increase in all the varieties but the magnitude of increase was greater in BAS-385 at all the measurements till 96h of salt treatment .The concentration of xylem 2-ipa was higher in BAS-385 till 48 h of salt treatment . The flux of both the t-zr and 2ipa was greater in the tolerant variety 96h after salt treatment. The basal level of ABA and cytokinin appears to play important role in determining the response of a variety to salt stress. The xylem flux of ABA and cytokinin (2-ipa and t

Mapping of QTLs for Leaf Malondialdehyde Content Associated with Stress Tolerance in Rice

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Jing JIANG

2009-03-01

Full Text Available Malondialdehyde (MDA is the final product of lipid peroxidation, and MDA content can reflect the stress tolerance of plants. To map QTLs conditioning the MDA content in rice leaves, a recombinant inbred line (RIL population with 247 lines derived from an indica-indica cross Zhenshan 97B×Milyang 46, and a linkage map consisting of 207 DNA markers were used. The RIL population showed a transgressive segregation in the MDA content of rice leaves. Two QTLs for the MDA content in rice leaves were detected in the intervals RG532–RG811 and RG381–RG236 on chromosome 1, with the additive effects from maternal and paternal parents, accounting for 4.33% and 4.62% of phenotype variations, respectively.

Hydraulic safety margins and embolism reversal in stems and leaves: Why are conifers and angiosperms so different?

Science.gov (United States)

Daniel M. Johnson; Katherine A. McCulloh; David R. Woodruff; Frederick C. Meinzer

2012-01-01

Angiosperm and coniferous tree species utilize a continuum of hydraulic strategies. Hydraulic safety margins (defined as differences between naturally occurring xylem pressures and pressures that would cause hydraulic dysfunction, or differences between pressures resulting in loss of hydraulic function in adjacent organs (e.g., stems vs. leaves) tend to be much greater...

Effects of 1,2,4-Trichlorobenzene and Mercury Ion Stress on Ca2+ Fluxion and Protein Phosphorylation in Rice

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Cai-lin GE

2007-12-01

Full Text Available The effects of 5 mg/L 1,2,4-trichlorobenzene (TCB and 0.1 mmol/L mercury ion (Hg2+ stresses on Ca2+ fluxion and protein phosphorylation in rice seedlings were investigated by isotope exchange kinetics and in vitro phosphorylation assay. The Ca2+ absorption in rice leaves and Ca2+ transportation from roots to leaves were promoted significantly in response to Hg2+ and TCB treatments for 4-48 h. The Ca2+ absorption peaks presented in the leaves when the rice seedlings were exposed to Hg2+ for 8-12 h or to TCB for 12-24 h. Several Ca2+ absorption peaks presented in the roots during rice seedlings being exposed to Hg2+ and TCB, and the first Ca2+ absorption peak was at 8 h after being exposed to Hg2+ and TCB. The result of isotope exchange kinetic analysis confirmed that short-term (8 h Hg2+ and TCB stresses caused Ca2+ channels or pumps located on plasmalemma to open transiently. The phosphorylation assay showed that short-term TCB stress enhanced protein phosphorylation in rice roots (TCB treatment for 4-8 h and leaves (TCB treatment for 4-24 h, and short-term (4-8 h Hg2+ stress also enhanced protein phosphorylation in rice leaves. The enhancement of protein phosphorylation in both roots and leaves corresponded with the first Ca2+ absorption peak, which confirmed that the enhancement of protein phosphorylation caused by TCB or Hg2+ stress might be partly triggered by the increases of cytosolic calcium. TCB treatment over 12 h inhibited protein phosphorylation in rice roots, which might be partly due to that TCB stress suppressed the protein kinase activity. Whereas, Hg2+ treatment inhibited protein phosphorylation in rice roots, and Hg2+ treatment over 12 h inhibited protein phosphorylation in rice leaves. This might be attributed to that not only the protein kinase activity, but also the expressions of phosphorylation proteins were restrained by Hg2+ stress.

Expressing OsMPK4 Impairs Plant Growth but Enhances the Resistance of Rice to the Striped Stem Borer Chilo suppressalis

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Xiaoli Liu

2018-04-01

Full Text Available Mitogen-activated protein kinases (MPKs play a central role not only in plant growth and development, but also in plant responses to abiotic and biotic stresses, including pathogens. Yet, their role in herbivore-induced plant defenses and their underlying mechanisms remain largely unknown. Here, we cloned a rice MPK gene, OsMPK4, whose expression was induced by mechanical wounding, infestation of the striped stem borer (SSB Chilo suppressalis, and treatment with jasmonic acid (JA, but not by treatment with salicylic acid (SA. The overexpression of OsMPK4 (oe-MPK4 enhanced constitutive and/or SSB-induced levels of JA, jasmonoyl-l-isoleucine (JA-Ile, ethylene (ET, and SA, as well as the activity of elicited trypsin proteinase inhibitors (TrypPIs, and reduced SSB performance. On the other hand, compared to wild-type plants, oe-MPK4 lines in the greenhouse showed growth retardation. These findings suggest that OsMPK4, by regulating JA-, ET-, and SA-mediated signaling pathways, functions as a positive regulator of rice resistance to the SSB and a negative regulator of rice growth.

Genome-wide analysis of esterase-like genes in the striped rice stem borer, Chilo suppressalis.

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Wang, Baoju; Wang, Ying; Zhang, Yang; Han, Ping; Li, Fei; Han, Zhaojun

2015-06-01

The striped rice stem borer, Chilo suppressalis, a destructive pest of rice, has developed high levels of resistance to certain insecticides. Esterases are reported to be involved in insecticide resistance in several insects. Therefore, this study systematically analyzed esterase-like genes in C. suppressalis. Fifty-one esterase-like genes were identified in the draft genomic sequences of the species, and 20 cDNA sequences were derived which encoded full- or nearly full-length proteins. The putative esterase proteins derived from these full-length genes are overall highly diversified. However, key residues that are functionally important including the serine residue in the active site are conserved in 18 out of the 20 proteins. Phylogenetic analysis revealed that most of these genes have homologues in other lepidoptera insects. Genes CsuEst6, CsuEst10, CsuEst11, and CsuEst51 were induced by the insecticide triazophos, and genes CsuEst9, CsuEst11, CsuEst14, and CsuEst51 were induced by the insecticide chlorantraniliprole. Our results provide a foundation for future studies of insecticide resistance in C. suppressalis and for comparative research with esterase genes from other insect species.

A Novel Gibberellin-Induced Gene from Rice and Its Potential Regulatory Role in Stem Growth1

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van der Knaap, Esther; Kim, Jeong Hoe; Kende, Hans

2000-01-01

Os-GRF1 (Oryza sativa-GROWTH-REGULATING FACTOR1) was identified in a search for genes that are differentially expressed in the intercalary meristem of deepwater rice (Oryza sativa L.) internodes in response to gibberellin (GA). Os-GRF1 displays general features of transcription factors, contains a functional nuclear localization signal, and has three regions with similarities to sequences in the database. One of these regions is similar to a protein interaction domain of SWI2/SNF2, which is a subunit of a chromatin-remodeling complex in yeast. The two other domains are novel and found only in plant proteins of unknown function. To study its role in plant growth, Os-GRF1 was expressed in Arabidopsis. Stem elongation of transformed plants was severely inhibited, and normal growth could not be recovered by the application of GA. Our results indicate that Os-GRF1 belongs to a novel class of plant proteins and may play a regulatory role in GA-induced stem elongation. PMID:10712532

Impact of rice cultivar and organ on elemental composition of phytoliths and the release of bio-available silicon

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Zimin eLi

2014-10-01

Full Text Available The continental bio-cycling of silicon (Si plays a key role in global Si cycle and as such partly controls global carbon (C budget through nutrition of marine and terrestrial biota, accumulation of phytolith-occluded organic carbon (PhytOC and weathering of silicate minerals. Despite the key role of elemental composition of phytoliths on their solubility in soils, the impact of plant cultivar and organ on the elemental composition of phytoliths in Si high-accumulator plants, such as rice (Oryza sativa is not yet fully understood. Here we show that rice cultivar significantly impacts the elemental composition of phytoliths (Si, Al, Fe and C in different organs of the shoot system (grains, sheath, leaf and stem. The amount of occluded OC within phytoliths is affected by contents of Si, Al and Fe in plants, while independent of the element composition of phytoliths. Our data document, for different cultivars, higher bio-available Si release from phytoliths of leaves and sheaths, which are characterized by higher enrichment with Al and Fe (i.e., lower Si/Al and Si/Fe ratios, compared to grains and stems. We indicate that phytolith solubility in soils may be controlled by rice cultivar and type of organs. Our results highlight that the role of the morphology, the hydration rate and the chemical composition in the solubility of phytoliths and the kinetic release of Si in soil solution needs to be studied further. This is central to a better understanding of the impact of soil amendment with different plant organs and cultivars on soil OC stock and on the delivery of dissolved Si as we show that sheath and leaf rice organs are both characterized by higher content of OC occluded in phytolith and higher phytolith solubility compared to grains and stems. Our study shows the importance of studying the impact of the agro-management on the evolution of sinks and sources of Si and C in soils used for Si-high accumulator plants.

Cyanobacteria-mediated phenylpropanoids and phytohormones in rice (Oryza sativa) enhance plant growth and stress tolerance.

Science.gov (United States)

Singh, Dhananjaya P; Prabha, Ratna; Yandigeri, Mahesh S; Arora, Dilip K

2011-11-01

Phenylpropanoids, flavonoids and plant growth regulators in rice (Oryza sativa) variety (UPR 1823) inoculated with different cyanobacterial strains namely Anabaena oryzae, Anabaena doliolum, Phormidium fragile, Calothrix geitonos, Hapalosiphon intricatus, Aulosira fertilissima, Tolypothrix tenuis, Oscillatoria acuta and Plectonema boryanum were quantified using HPLC in pot conditions after 15 and 30 days. Qualitative analysis of the induced compounds using reverse phase HPLC and further confirmation with LC-MS/MS showed consistent accumulation of phenolic acids (gallic, gentisic, caffeic, chlorogenic and ferulic acids), flavonoids (rutin and quercetin) and phytohormones (indole acetic acid and indole butyric acid) in rice leaves. Plant growth promotion (shoot, root length and biomass) was positively correlated with total protein and chlorophyll content of leaves. Enzyme activity of peroxidase and phenylalanine ammonia lyase and total phenolic content was fairly high in rice leaves inoculated with O. acuta and P. boryanum after 30 days. Differential systemic accumulation of phenylpropanoids in plant leaves led us to conclude that cyanobacterial inoculation correlates positively with plant growth promotion and stress tolerance in rice. Furthermore, the study helped in deciphering possible mechanisms underlying plant growth promotion and stress tolerance in rice following cyanobacterial inoculation and indicated the less explored avenue of cyanobacterial colonization in stress tolerance against abiotic stress.

Automated rice leaf disease detection using color image analysis

Science.gov (United States)

Pugoy, Reinald Adrian D. L.; Mariano, Vladimir Y.

2011-06-01

In rice-related institutions such as the International Rice Research Institute, assessing the health condition of a rice plant through its leaves, which is usually done as a manual eyeball exercise, is important to come up with good nutrient and disease management strategies. In this paper, an automated system that can detect diseases present in a rice leaf using color image analysis is presented. In the system, the outlier region is first obtained from a rice leaf image to be tested using histogram intersection between the test and healthy rice leaf images. Upon obtaining the outlier, it is then subjected to a threshold-based K-means clustering algorithm to group related regions into clusters. Then, these clusters are subjected to further analysis to finally determine the suspected diseases of the rice leaf.

Identification of a Gravitropism-Deficient Mutant in Rice

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He Yan

2017-03-01

Full Text Available A gravitropism-deficient mutant M96 was isolated from a mutant bank, generated by ethyl methane sulfonate (EMS mutagenesis of indica rice accession ZJ100. The mutant was characterized as prostrate growth at the beginning of germination, and the prostrate growth phenotype ran through the whole life duration. Tiller angle and tiller number of M96 increased significantly in comparison with the wild type. Tissue section observation analysis indicated that asymmetric stem growth around the second node occurred in M96. Genetic analysis and gene mapping showed that M96 was controlled by a single recessive nuclear gene, tentatively termed as gravitropism-deficient M96 (gdM96, which was mapped to a region of 506 kb flanked by markers RM5960 and InDel8 on the long arm of chromosome 11. Sequencing analysis of the open reading frames in this region revealed a nucleotide substitution from G to T in the third exon of LOC_Os11g29840. Additionally, real-time fluorescence quantitative PCR analysis showed that the expression level of LOC_Os11g29840 in the stems was much higher than in the roots and leaves in M96. Furthermore, the expression level was more than four times in M96 stem than in the wild type stem. Our results suggested that the mutant gene was likely a new allele to the reported gene LAZY1. Isolation of this new allele would facilitate the further characterization of LAZY1.

Temporal variability in trace metal solubility in a paddy soil not reflected in uptake by rice (Oryza sativa L.).

Science.gov (United States)

Pan, Yunyu; Koopmans, Gerwin F; Bonten, Luc T C; Song, Jing; Luo, Yongming; Temminghoff, Erwin J M; Comans, Rob N J

2016-12-01

Alternating flooding and drainage conditions have a strong influence on redox chemistry and the solubility of trace metals in paddy soils. However, current knowledge of how the effects of water management on trace metal solubility are linked to trace metal uptake by rice plants over time is still limited. Here, a field-contaminated paddy soil was subjected to two flooding and drainage cycles in a pot experiment with two rice plant cultivars, exhibiting either high or low Cd accumulation characteristics. Flooding led to a strong vertical gradient in the redox potential (Eh). The pH and Mn, Fe, and dissolved organic carbon concentrations increased with decreasing Eh and vice versa. During flooding, trace metal solubility decreased markedly, probably due to sulfide mineral precipitation. Despite its low solubility, the Cd content in rice grains exceeded the food quality standards for both cultivars. Trace metal contents in different rice plant tissues (roots, stem, and leaves) increased at a constant rate during the first flooding and drainage cycle but decreased after reaching a maximum during the second cycle. As such, the high temporal variability in trace metal solubility was not reflected in trace metal uptake by rice plants over time. This might be due to the presence of aerobic conditions and a consequent higher trace metal solubility near the root surface, even during flooding. Trace metal solubility in the rhizosphere should be considered when linking water management to trace metal uptake by rice over time.

Reproducible and expedient rice regeneration system using in vitro ...

African Journals Online (AJOL)

Inevitable prerequisite for expedient regeneration in rice is the selection of totipotent explant and developing an apposite combination of growth hormones. Here, we reported a reproducible regeneration protocol in which basal segments of the stem of the in vitro grown rice plants were used as ex-plant. Using the protocol ...

Isolation and characterization of plant growth promoting endophytic diazotrophic bacteria from Korean rice cultivars.

Science.gov (United States)

Ji, Sang Hye; Gururani, Mayank Anand; Chun, Se-Chul

2014-01-20

We have isolated 576 endophytic bacteria from the leaves, stems, and roots of 10 rice cultivars and identified 12 of them as diazotrophic bacteria using a specific primer set of nif gene. Through 16S rDNA sequence analysis, nifH genes were confirmed in the two species of Penibacillus, three species of Microbacterium, three Bacillus species, and four species of Klebsiella. Rice seeds treated with these plant growth-promoting bacteria (PGPB) showed improved plant growth, increased height and dry weight and antagonistic effects against fungal pathogens. In addition, auxin and siderophore producing ability, and phosphate solubilizing activity were studied for the possible mechanisms of plant growth promotion. Among 12 isolates tested, 10 strains have shown higher auxin producing activity, 6 isolates were confirmed as strains with high siderophore producing activity while 4 isolates turned out to have high phosphate-solubilizing activity. These results strongly suggest that the endophytic diazotrophic bacteria characterized in this study could be successfully used to promote plant growth and inducing fungal resistance in plants. Copyright © 2013 Elsevier GmbH. All rights reserved.

Performance of different rice cultivars and insecticides against tryporyza incertulas (walker) and cnaphalocrocis medinalis (guenee)

International Nuclear Information System (INIS)

Rashid, M.M.U.; Khattak, M.K.; Momin, A.; Amir, M.; Latif, A.

2013-01-01

Studies were conducted to determine the toxicity of Roll Up (7.2% G), Furadan (3G), Solomon (300-0-Teq), Belt (48% SC), Karuz (4% GR) and Shark Super (6% G) and relative resistance of rice varieties IRRI-6, KSK-282, DR-83, Basmati-370, Basmati-385 and Super Basmati against rice stem borer and rice leaf folder and their effect on yield ha/sup -1/. Roll Up and Shark Super ranked first in their efficacy against rice stem borer; as 0.64% and 0.63% dead hearts and 0.32 and 0.33% white heads were recorded, respectively, and which were significantly (P < 0.05) lower than control. Solomon with 0.73% infestation was the most effective insecticide against rice leaf folder. Rice varieties IRRI-6 and KSK-282 were the most resistant varieties against rice stem borer; as 14.73% and 18.34% dead hearts, and 4.33% and 4.77% white heads were significantly (P < 0.05) lower than the other tested varieties. Similarly IRRI-6, KSK-282 and DR-83 also showed resistance to rice leaf folder. Basmati-385 was the most susceptible variety against rice leaf folder. KSK-282 with 5656 kg ha/sup -1/ yield ranked first. Plots treated with shark super resulted in to highest (7014 kg ha/sup -1/) yield whereas; plots treated with Karuz resulted into lowest (5984 kg ha/sup -1/) yield. (author)

Realistic Simulation of Rice Plant

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Wei-long DING

2011-09-01

Full Text Available The existing research results of virtual modeling of rice plant, however, is far from perfect compared to that of other crops due to its complex structure and growth process. Techniques to visually simulate the architecture of rice plant and its growth process are presented based on the analysis of the morphological characteristics at different stages. Firstly, the simulations of geometrical shape, the bending status and the structural distortion of rice leaves are conducted. Then, by using an improved model for bending deformation, the curved patterns of panicle axis and various types of panicle branches are generated, and the spatial shape of rice panicle is therefore created. Parametric L-system is employed to generate its topological structures, and finite-state automaton is adopted to describe the development of geometrical structures. Finally, the computer visualization of three-dimensional morphologies of rice plant at both organ and individual levels is achieved. The experimental results showed that the proposed methods of modeling the three-dimensional shapes of organs and simulating the growth of rice plant are feasible and effective, and the generated three-dimensional images are realistic.

Composition of the essential oil constituents from leaves and stems of Korean Coriandrum sativum and their immunotoxicity activity on the Aedes aegypti L.

Science.gov (United States)

Chung, Ill-Min; Ahmad, Ateeque; Kim, Sun-Jin; Naik, Poornanand Madhava; Nagella, Praveen

2012-02-01

The leaves and stems of Coriandrum sativum were extracted and the essential oil composition and immunotoxicity effects were studied. The analyses were conducted by gas chromatography-mass spectroscopy (GC-MS), which revealed the essential oils of C. sativum leaves and stems. Thirty-nine components representing 99.62% of the total oil were identified from the leaves. The major components are cyclododecanol (23.11%), tetradecanal (17.86%), 2-dodecenal (9.93%), 1-decanol (7.24%), 13-tetradecenal (6.85%), 1-dodecanol (6.54%), dodecanal (5.16%), 1-undecanol (2.28%), and decanal (2.33%). Thirty-eight components representing 98.46% of the total oil were identified from the stems of the coriander. The major components are phytol (61.86%), 15-methyltricyclo[6.5.2(13,14),0(7,15)]-pentadeca-1,3,5,7,9,11,13-heptene (7.01%), dodecanal (3.18%), and 1-dodecanol (2.47%). The leaf oil had significant toxic effects against the larvae of Aedes aegypti with an LC₅₀ value of 26.93 ppm and an LC₉₀ value of 37.69 ppm and the stem oil has toxic effects against the larvae of A. aegypti with an LC₅₀ value of 29.39 ppm and an LC₉₀ value of 39.95 ppm. Also, the above data indicate that the major compounds may play an important role in the toxicity of essential oils.

Fatty acid composition and antibacterial potential of Cassia tora (leaves and stem collected from different geographic areas of India

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Shipra Shukla

2018-01-01

Full Text Available The comparative analysis of the fatty acid composition of Cassia tora (leaves and stem was determined using gas chromatography–mass spectrometry. Twenty-seven fatty acids were identified in C. tora (leaves and stem which was collected from three different geographical areas of India: Lucknow (Uttar Pradesh, Nainital (Uttarakhand, and Bhavnagar (Gujarat, coded as CT-1, CT-2, and CT-3, respectively. The gas chromatography–mass spectrometry analysis showed the presence of various saturated and unsaturated fatty acids. The major fatty acids found were palmitic acid, linoleic acid, linolenic acid, margaric acid, melissic acid, and behenic acid. The highest amounts of saturated fatty acids were found in leaves of C. tora collected from Bhavnagar (Gujarat (60.7% ± 0.5%. Thus, the study reveals that C. tora has a major amount of nutritionally important fatty acids, along with significant antimicrobial potential. Fatty acids play a significant role in the development of fat products with enhanced nutritional value and clinical application. Remarkable differences were found in the present study between fatty acid profiles of C. tora collected from different locations in India. To the best of our knowledge there is no previously reported comparative study of the fatty acids of C. tora.

Salicilatos isolados de folhas e talos de Salix martiana Leyb. (Salicaceae Salicylates isolated from leaves and stems of Salix martiana Leyb. (Salicaceae

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Carromberth Carioca Fernandes

2009-01-01

Full Text Available Salix martiana Leyb. is an endemic species from the Amazon river floodplain areas (varzeas, of the State of Amazonas. Stems and leaves were extracted with dichloromethane, methanol and hydro-alcohol and these extracts were fractionated by using conventional chromatographic techniques. The major substances isolated, salicin and trichocarposide (6-0-p-coumaroyl salicin, were determined through analyses of NMR 1D (¹H and 13C and NMR 2D (gHSQC and gHMBC. These compounds were isolated for the first time in Salix martiana Leyb. (Salicaceae. The percentage of these compounds in S. martiana is very high. The extracts were analyzed for their DPPH antioxidant capacity and the methanolic from the leaves and the hydro-alcoholic from the stems were the more active.

Salicylates isolated from leaves and stems of Salix martiana Leyb. (Salicaceae); Salicilatos isolados de folhas e talos de Salix martiana Leyb. (Salicaceae)

Energy Technology Data Exchange (ETDEWEB)

Fernandes, Carromberth Carioca [Universidade Federal do Acre (UFAC), Rio Branco, AC (Brazil). Centro de Ciencias Biologicas e da Natureza; Cursino, Lorena Mayara de Carvalho; Novaes, Jussival de Abreu Pinheiro; Demetrio, Camilla Avelino; Pereira Junior, Orlando Liborio; Nunez, Cecilia Veronica [Instituto de Pesquisa da Amazonia (INPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Produtos Naturais; Amaral, Ieda Leao do [Instituto de Pesquisa da Amazonia (INPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Botanica

2009-07-01

Salix martiana Leyb. is an endemic species from the Amazon river floodplain areas (varzeas), of the State of Amazonas. Stems and leaves were extracted with dichloromethane, methanol and hydro-alcohol and these extracts were fractionated by using conventional chromatographic techniques. The major substances isolated, salicin and trichocarposide (6-0-p-coumaroyl salicin), were determined through analyses of NMR 1D ({sup 1}H and {sup 13}C) and NMR 2D (gHSQC and gHMBC). These compounds were isolated for the first time in Salix martiana Leyb. (Salicaceae). The percentage of these compounds in S. martiana is very high. The extracts were analyzed for their DPPH antioxidant capacity and the methanolic from the leaves and the hydro-alcoholic from the stems were the more active. (author)

Quantitative elemental localisation in leaves and stems of nickel hyperaccumulating shrub Hybanthusfloribundus subsp. floribundus using micro-PIXE spectroscopy

International Nuclear Information System (INIS)

Kachenko, Anthony G; Singh, Balwant; Bhatia, Naveen P; Siegele, Rainer

2008-01-01

Hybanthusfloribundus (Lindl.) F.Muell. subsp. floribundus is a native Australian nickel (Ni) hyperaccumulating shrub and a promising species for rehabilitation and phytoremediation of Ni tailings. Spatial localisation and quantification of Ni in leaf and stem tissues of H.floribundus subsp. floribundus was studied using micro-proton-induced X-ray emission (micro-PIXE) spectroscopy. Young plants, grown in a potting mix under controlled glasshouse conditions were exposed to Ni concentrations of 0 and 26 mM kg -1 for 20 weeks. Leaf and stem samples were hand-sectioned and freeze-dried prior to micro-PIXE analysis. Elemental distribution maps of leaves revealed Ni concentration of 7800 mg kg -1 dry weight (DW) in whole leaf sections, which was identical to the bulk tissue analysis. Elemental maps showed that Ni was preferentially localised in the adaxial epidermis (10,000 mg kg -1 DW) and reached a maximum of up to 10,000 mg kg -1 DW in the leaf margin. Freeze-dried stem sections from the same plants contained lower Ni than leaf tissues (1800 mg kg -1 versus 7800 mg kg -1 DW, respectively), however did not resolve a clear pattern of compartmentalisation across different anatomical regions. Our results suggest localisation in epidermal cells is an important physiological mechanism involved in Ni accumulation and tolerance in leaves of H.floribundus subsp. floribundus

Improved performance of photosynthetic light response equations with unified parameters for rice leaves with different SPAD values

International Nuclear Information System (INIS)

Xu, J.; Peng, S.; Kong, W.

2015-01-01

The rectangular hyperbola (RH), Mitscherlich (M) and YE equation were applied to describe the photosynthetic light response (PLR) curves measured from rice leaves with different SPAD values, to reveal the relationship between SPAD values and parameters in different equations, and to establish the modified PLR equations. The parameters in PLR equations are largely varied. SPAD value, as an indicator of leaf N contents, was highly correlated to the parameter of Pnmax in RH, M and YE equations. Incorporating the factor SPAD into PLR equations, the modified equations (MRH, MM, and MYE) were established which were feasible to describing the PLR curves for leaves with different SPAD values using the identical parameters for the ten PLR curves as a whole, and perform much better than the general PLR equations (GRH, GM, and GYE). It indicated that incorporating easy available indicators of leaf physiological and morphological traits in the PLR equations, such as SPAD as an indicator of leaf N or Chlorophyll contents, is an easy way to overcome the shortcoming of parameters variation in PLR equations between individuals of the same specie growing in different environments. Further validation should be done for different crops with both SPAD and other possible factors. (author)

Expressing OsMPK4 Impairs Plant Growth but Enhances the Resistance of Rice to the Striped Stem Borer Chilo suppressalis

OpenAIRE

Xiaoli Liu; Jiancai Li; Liping Xu; Qi Wang; Yonggen Lou

2018-01-01

Mitogen-activated protein kinases (MPKs) play a central role not only in plant growth and development, but also in plant responses to abiotic and biotic stresses, including pathogens. Yet, their role in herbivore-induced plant defenses and their underlying mechanisms remain largely unknown. Here, we cloned a rice MPK gene, OsMPK4, whose expression was induced by mechanical wounding, infestation of the striped stem borer (SSB) Chilo suppressalis, and treatment with jasmonic acid (JA), but not ...

Conversion efficiency in the shrimp, Metapenaeus monoceros (Fabricius), fed on decomposed mangrove leaves

Digital Repository Service at National Institute of Oceanography (India)

Sumitra-Vijayaraghavan; Ramadhas, V.

Feeding experiments were carried out with Metapenaeus monoceros using mangrove leaves at different stages of decomposition, in combination with rice bran. Maximum conversion efficiency was found in shrimps fed completely decomposed mangrove leaves...

Eucalyptus oleosa Essential Oils: Chemical Composition and Antimicrobial and Antioxidant Activities of the Oils from Different Plant Parts (Stems, Leaves, Flowers and Fruits

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Mohamed Larbi Khouja

2011-02-01

Full Text Available Essential oils obtained by hydrodistillation from the different parts (stems, adult leaves, immature flowers and fruits of Eucalyptus oleosa were screened for their antioxidant and antimicrobial properties and their chemical composition. According to GC-FID and GC-MS, the principal compound of the stem, immature flowers and the fruit oils was 1,8-cineole, representing 31.5%, 47.0% and 29.1%, respectively. Spathulenol (16.1% and γ-eudesmol (15.0% were the two principal compounds of adult leaves oil. In the DPPH (1,1-diphenyl-2-picrylhydrazyl assay, the oils of the four parts showed moderate antioxidant activity. In the ABTS (2,2’-azinobis-3-ethylbenzothiazoline-6-sulphonate assay, the most active part was the adult leaves, with a IC50 value 13.0 ± 0.6 mg/L, followed by stems (IC50 = 43.5 ± 1.4 mg/L. The essential oils showed a better antibacterial activity against Gram-positive and Gram-negative bacteria, and a significant antifungal activity also was observed against yeast-like fungi. A strong correlations between oxygenated monoterpenes and antimicrobial activity (especially 1,8-cineole were noted (R2 = 0.99, 0.97 and 0.79 for B. subtilis, P. aeruginosa and C. albicans, respectively.

Chemical diversity of essential oils from flowers, leaves, and stems of Rhanterium epapposum Oliv. growing in northern border region of Saudi Arabia

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Marwa Awad

2016-09-01

Conclusions: Essential oils from flowers, leaves and stems of R. epapposum growing in northern border region of Saudi Arabia are considered as a rich source of monoterpenes which have biological activities.

Methodology development for area determination of rice planted paddy using RADARSAT data

International Nuclear Information System (INIS)

Ishitsuka, N.; Saito, G.; Murakami, T.; Ogawa, S.; Okamoto, K.

2003-01-01

Every year, the agricultural statistics section of the Japanese government announces rice planting paddy area and rice yield per hectare (ha). At present, the rice planting paddy area is calculated based on field survey by human power. In future, the Japanese government should like to determine the rice transplanted paddy area using remote sensing. Already, some results have come out using satellite-borne optical sensors. However, Japan has a rainy-season at crop growing time, and therefore it is difficult, under such weather condition, to make accurate and consistent observation of paddy fields every year by optical means. On the other hand, Synthetic Aperture Radar (SAR) is capable of observing the earth's surface without influence of clouds. Making use of this all-weather imaging capability, we are currently developing a method to determine the rice planted paddy area using SAR data acquired by RADARSAT. Paddy fields are filled with water during rice-planting period. When the microwave is incident on the filled paddy fields, it is reflected away from the SAR antenna by the water surface acting like a mirror. This phenomenon is called 'specular reflection'. The microwave backscatter is therefore small from the surface covered with water. Thus, the radar cross section (RCS) is very small from rice paddies at a transplanting period due to the specular reflection, and it increases with the growth of rice plants because of volume scatter by stems and leaves, and also by multiple reflection between the water surface and rice plants. In our study, this characteristic is used to develop methods of estimating rice paddy area. Our study area is the Saga plain in the southeast Japan. First, We determine the threshold of image intensity to separate the land and water areas using the histogram and maps. Next, we develop techniques of classification, utilizing (1) RADARSAT and optical data, (2) two multi-temporal RADARSAT data, (3) RADARSAT and GIS data, and (4

Enhanced degradation of chlorpyrifos in rice (Oryza sativa L.) by five strains of endophytic bacteria and their plant growth promotional ability.

Science.gov (United States)

Feng, Fayun; Ge, Jing; Li, Yisong; He, Shuang; Zhong, Jianfeng; Liu, Xianjing; Yu, Xiangyang

2017-10-01

Endophytic bacteria reside in plant tissues, such as roots, stems, leaves and seeds. Most of them can stimulate plant growth or alleviate phytotoxicity of pollutants. There are handful species with dual functions stimulating plant growth and degrading pollutants have been reported. Five endophytic bacteria were isolated from chlorpyrifos (CP) treated rice plants and identified as Pseudomonas aeruginosa strain RRA, Bacillus megaterium strain RRB, Sphingobacterium siyangensis strain RSA, Stenotrophomonas pavanii strain RSB and Curtobacterium plantarum strain RSC according to morphological characteristics, physiological and biochemical tests, and 16S rDNA phylogeny. All of them possessed some plant growth promotional traits, including indole acetic acid and siderophore production, secretion of phosphate solubilization and 1-aminocyclopropane-1-carboxylate deaminase. The bacteria were marked with the green fluorescent protein (gfp) gene and successfully colonized into rice plants. All isolates were able to degrade CP in vitro and in vivo. The five isolates degraded more than 90% of CP in 24 h when the initial concentration was lower than 5 mg/L. CP degradation was significantly enhanced in the infested rice plants and rice grains. The final CP residual was reduced up to 80% in the infested rice grains compared to the controls. The results indicate that these isolates are promising bio-inoculants for the removal or detoxification of CP residues in rice plants and grains. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ethnobotanicals for Storage Pest Management: Effect of powdered leaves of Olax zeylanica in suppressing infestations of rice weevil Sitophilus oryzae (Coleoptera: Curculionidae

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Sachini Dinusha Fernando

2012-05-01

Full Text Available Abstract The rice weevil Sitophilus oryzae is considered the major problem in stored rice in Sri Lanka. Due to the adverse effects of pesticide usage, research on the re-evaluation and use of many ethnobotanicals as alternative storage pest control agents has been intensified. Although plant materials with insecticidal properties provide small-scale farmers with a locally available, eco-friendly and inexpensive method of control of storage insect pests, lack of understanding and knowledge prevent their widespread application. The present study was therefore undertaken to investigate the effectiveness of the botanical Olax zeylanica in controlling infestations of the rice weevil with the view of fulfilling this lack. In two separate bioassays, contact/feeding and fumigant toxicity of powdered leaves of O. zeylanica were tested against 1-7 days old adults under laboratory conditions. All experiments were conducted using a no-choice bioassay apparatus. Contact/feeding toxicity was tested by directly exposing weevils to 1.0, 3.0, 5.0 and 7.5g of leaf powder mixed with 100g of rice grains while fumigant toxicity was evaluated by using the same doses where weevils were exposed to fumes emitted from the leaf powders. In both bioassays 100% mortality of the weevils was observed within 18 hours of exposure to 3.0, 5.0 and 7.5g doses of leaf powder. Percentage weevil mortality in treated rice tested with three doses of leaf powder at all the time intervals (except for 1.0g was significantly higher (p < 0.05 than that of the corresponding control. No Contact/feeding toxicity was recorded when weevils were directly exposed to 1.0g leaf powder whereas only 14% weevil mortality was observed even after 24hours of exposure to fumes of leaf powder. Results also revealed that weevil mortality increased both with increasing dose and time of exposure. It is of interest to note that in both bioassays a 100% weevil mortality was obtained after 18 hours of exposure to

Alterations in Gas Exchange and Oxidative Metabolism in Rice Leaves Infected by Pyricularia oryzae are Attenuated by Silicon.

Science.gov (United States)

Domiciano, Gisele Pereira; Cacique, Isaías Severino; Chagas Freitas, Cecília; Filippi, Marta Cristina Corsi; DaMatta, Fábio Murilo; do Vale, Francisco Xavier Ribeiro; Rodrigues, Fabrício Ávila

2015-06-01

Rice blast, caused by Pyricularia oryzae, is the most important disease in rice worldwide. This study investigated the effects of silicon (Si) on the photosynthetic gas exchange parameters (net CO2 assimilation rate [A], stomatal conductance to water vapor [gs], internal-to-ambient CO2 concentration ratio [Ci/Ca], and transpiration rate [E]); chlorophyll fluorescence a (Chla) parameters (maximum photochemical efficiency of photosystem II [Fv/Fm], photochemical [qP] and nonphotochemical [NPQ] quenching coefficients, and electron transport rate [ETR]); concentrations of pigments, malondialdehyde (MDA), and hydrogen peroxide (H2O2); and activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), and lypoxigenase (LOX) in rice leaves. Rice plants were grown in a nutrient solution containing 0 or 2 mM Si (-Si or +Si, respectively) with and without P. oryzae inoculation. Blast severity decreased with higher foliar Si concentration. The values of A, gs and E were generally higher for the +Si plants in comparison with the -Si plants upon P. oryzae infection. The Fv/Fm, qp, NPQ, and ETR were greater for the +Si plants relative to the -Si plants at 108 and 132 h after inoculation (hai). The values for qp and ETR were significantly higher for the -Si plants in comparison with the +Si plants at 36 hai, and the NPQ was significantly higher for the -Si plants in comparison with the +Si plants at 0 and 36 hai. The concentrations of Chla, Chlb, Chla+b, and carotenoids were significantly greater in the +Si plants relative to the -Si plants. For the -Si plants, the MDA and H2O2 concentrations were significantly higher than those in the +Si plants. The LOX activity was significantly higher in the +Si plants than in the -Si plants. The SOD and GR activities were significantly higher for the -Si plants than in the +Si plants. The CAT and APX activities were significantly higher in the +Si plants than in the -Si plants. The supply of

Quantitative determination of total and individual flavonoids in stems and leaves of Buddleja davidii and Buddleja albiflora

OpenAIRE

Ying, Cheng; Wan, Dingrong

2012-01-01

Background: Buddleja davidii and B. albiflora are two different original plants of the famous crude medicine "Diaoyangchen." Materials and Methods: An ultraviolet-visible spectrophotometric method and a HPLC method were used for the determination of total and individual flavonoids (luteolin and apigenin) contents from their stems and leaves for the first time. Results: From the comparative evaluation, remarkable differences in flavonoids contents were observed between different origins and di...

137Cs absorption by growing rice planted in pot soil from Qinshan and Daya Bay area

International Nuclear Information System (INIS)

Shang Zhaorong; Yu Fengyi; Lu Zixian

1999-01-01

The pot experiment of growing rice contaminated with 137 Cs solution was designed as follows. (1) The same volume of 137 Cs solution was irrigated into rice soil from Guantang District around Qinshan NPP in seedling stage, booting stage and milk stage respectively with the same Specific Activity (SA) of 370 Bq/g soil , and the rice was sampled after maturity. (2) In the seedling stage, the rice cultured in the soil from Guantang District was irrigated by four different SA of 0.37, 3.7, 37 and 370 Bq/g soil respectively, and sampled after 30, 60 and 90 d. (3) Transfer Factors (TF) of edible parts of rice on five different soils were calculated for three different stage and four different 137 Cs levels. The results show that: 1) TF of Shenzhen soil is the highest with 1.86 in seed and 2.22 in stem and 4.05 in leaf, Changchuanba soil is the lowest with 0.09 in seed and 0.20 in stem and 0.20 in leaf, among the five different soils. 2) TF in milk stage is the highest with 0.46 in seed and 2.29 in stem and 2.87 in leaf, and booting stem is lowest with 0.09 in seed and 0.17 in stem and 0.17 in leaf, among the three different stage. 3) TF of soil with contamination in 0.37 Bq/g soil is the highest with 1.08 in seed and 3.70 in stem and 4.32 in leaf, and the contamination in 37 Bq/g soil is the lowest with 0.06 in seed and 0.10 in stem and 0.14 in leaf, among four different contamination levels

Serratia oryzae sp. nov., isolated from rice stems.

Science.gov (United States)

Zhang, Cai-Wen; Zhang, Jun; Zhao, Juan-Juan; Zhao, Xia; Zhao, Dong-Fang; Yin, Hua-Qun; Zhang, Xiao-Xia

2017-08-01

A novel endophytic bacterium, strain J11-6T, was isolated from rice stems. Its taxonomic position was investigated using a polyphasic approach. The novel strain was Gram-staining-negative, facultatively anaerobic, motile and rod-shaped. Although the results of phylogenetic analysis based on 16S rRNA gene sequences indicated that J11-6T represented a member of the genus Rahnella, multilocus sequence analysis (MLSA) on the basis of concatenated partial atpD, gyrB, rpoB and infB gene sequences showed a clear distinction of J11-6T from the type strains of species of the genus Rahnella but indicated that it lay within the clade of the genus Serratia. The phylogenetically closest species were Serratia fonticola and Serratia aquatilis on the basis of the results of the MLSA phylogenetic analysis. The predominant cellular fatty acids were C16 : 1ω7c (38.7 %) and C16 : 0 (25.0 %). The DNA G+C content was 53.2 mol%. The DNA-DNA relatedness was 17.4 % between J11-6T and Rahnella aquatilis CIP 78.65T, and 29.2 % between J11-6T and S. fonticola LMG 7882T which indicates that this strain represents a novel species of the genus Serratia. Characterization by genotypic and phenotypic analysis indicated that J11-6T (=ACCC 19934T=KCTC 52529T) represents a novel species of the genus Serratia, for which the name Serratia oryzae sp. nov. is proposed.

Uptake of C-14 tagged acetate by rice in a paddy soil-to-rice plant system

Energy Technology Data Exchange (ETDEWEB)

Ishii, Nobuyoshi; Tagami, Keiko; Uchida, Shigeo [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

2014-07-01

Geological disposal of Transuranic (TRU) waste is planned to avoid radiation exposure to the public. One of the dominant nuclides contributing to the dose from TRU waste is C-14, which is long-lived and has very poor sorption properties on natural geological media. Therefore, there are some concerns regarding possible migration of C-14 to the living environments. For the public health safety, it is necessary to clarify pathways of C-14 to human beings in the environment. Intake of C-14 from food source is one of important pathways. In the present study, we examined transfer of C-14 to various parts of rice plant in a paddy soil-to-rice plant system. Rice seedlings in Wagner pots (n=12) were grown for about two months from 7 May 2012 under natural light. The grown plants were moved to a closed chamber on 5 July 2012. The rice plants were grown without water supply from 5 July 2012, and then one liter of C-14 tagged acetate (1.85 MBq) was supplied to the rice plants in the spiked group (n=8) just once on 9 July 2012. For the rice plants in the control group (n=4), uncontaminated water was supplied. These rice plants were air-dried after a harvest on 23 August 2012 and divided into four parts: white rice, bran, rice husk, and the stem and leaf part. The activities of C-14 in the divided parts and air-dried soil samples were determined with a liquid scintillation counting system. Radiocarbon was detected even in the rice plants of the control group. However, the C-14 activity in the soil of the control group was less than the detection limit (1.0 Bq/g). The C-14 activities for the control group decreased in the order of rice husk, bran, white rice, and the stem and leaf part. The detection of C-14 in the control group may be caused by the release of C-14 tagged carbon dioxide from the spiked group. That is, C-14 tagged acetate was converted to carbon dioxide by microbial activity in the spiked group, and then some of the released carbon dioxide was assimilated into

Aquaporin Expression and Water Transport Pathways inside Leaves Are Affected by Nitrogen Supply through Transpiration in Rice Plants

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Lei Ding

2018-01-01

Full Text Available The photosynthetic rate increases under high-N supply, resulting in a large CO2 transport conductance in mesophyll cells. It is less known that water movement is affected by nitrogen supply in leaves. This study investigated whether the expression of aquaporin and water transport were affected by low-N (0.7 mM and high-N (7 mM concentrations in the hydroponic culture of four rice varieties: (1 Shanyou 63 (SY63, a hybrid variant of the indica species; (2 Yangdao 6 (YD6, a variant of indica species; (3 Zhendao 11 (ZD11, a hybrid variant of japonica species; and (4 Jiuyou 418 (JY418, another hybrid of the japonica species. Both the photosynthetic and transpiration rate were increased by the high-N supply in the four varieties. The expressions of aquaporins, plasma membrane intrinsic proteins (PIPs, and tonoplast membrane intrinsic protein (TIP were higher in high-N than low-N leaves, except in SY63. Leaf hydraulic conductance (Kleaf was lower in high-N than low-N leaves in SY63, while Kleaf increased under high-N supply in the YD6 variant. Negative correlations were observed between the expression of aquaporin and the transpiration rate in different varieties. Moreover, there was a significant negative correlation between transpiration rate and intercellular air space. In conclusion, the change in expression of aquaporins could affect Kleaf and transpiration. A feedback effect of transpiration would regulate aquaporin expression. The present results imply a coordination of gas exchange with leaf hydraulic conductance.

A dominant mutation of TWISTED DWARF 1 encoding an alpha-tubulin protein causes severe dwarfism and right helical growth in rice.

Science.gov (United States)

Sunohara, Hidehiko; Kawai, Takayuki; Shimizu-Sato, Sae; Sato, Yutaka; Sato, Kanna; Kitano, Hidemi

2009-06-01

Dwarfism is a common type of mutation in many plant species. The pathways and factors regulating biosynthesis and signaling of several plant growth regulators have been clarified through analyses of dwarf mutants in rice, Arabidopsis, pea, and maize. However, the genetic mechanisms controlling dwarfism are not well characterized, and the causal genes underlying most dwarf mutants are still uncovered. Here, we report a dominant mutant, Twisted dwarf 1-1 (Tid1-1), showing dwarfism and twisted growth in rice. Tid1-1 exhibit right helical growth of the leaves and stem and shortening of the roots. They also show an increased number of cells in the shoot apical meristem. Cells in the leaves of Tid1-1 are often ill-shapen, possibly owing to irregular cell division. Cell elongation in roots is suppressed in the elongation zone, and cells in the root apical meristem are enlarged. Map-based cloning of TID1 revealed that it encodes an alpha-tubulin protein comprising microtubules and is an ortholog of Arabidopsis LEFTY genes. Our analysis of the Tid1-1 mutant revealed that the dynamics of microtubules affects not only anisotropic growth in both dicots and monocots, but also meristematic activity and gross plant morphology.

The fate of the dry matter, carbohydrates and 14C lost from the leaves and stems of wheat during grain filling

International Nuclear Information System (INIS)

Austin, R.B.; Edrich, J.A.; Ford, M.A.; Blackwell, R.D.

1977-01-01

In a field study with six winter wheat genotypes losses of dry matter from the stems between 30 June and maturity averaged 172 g m - 2 (range 82 to 256), there being significant differences in loss between genotypes. Respiration from the stems during the same period was estimated to amount to 106 g m -2 (range 104 to 225). The amount of dry matter mobilized from the stems, calculated by difference, was estimated as 66 g m -2 . The loss of ethanol- and water-soluble carbohydrate from the stems (170 g m -2 ; range 124 to 215) was very similar to the dry weight loss. Carbon-14 labelling was used to trace the time course and the amount of the movement of assimilates from the vegetative organs to the grain. Only 14.3 per cent (range 10.3 to 21.0) of the products of photosynthesis over the period 21 May to 20 June were relocated to the grains. This relocation amounted to an average of 7 per cent (range 5.7 to 11.4) of the final grain weight. It was estimated that during the 18 days following anthesis on 20 June photosynthesis contributed 48 per cent (range 39 to 55) of the final grain dry weight. Of this, about half was translocated to the grain within 10 days of initial assimilation. The remainder appeared to be stored temporarily in the stems and leaves and translocated to the grains during the period 17 to 29 July. In general, relocation of dry matter from the vegetative organs to the grains, assessed by carbon-14 labelling, was greatest in those genotypes (Hobbit and Sportsman) which lost most dry weight from the stems and leaves. (author)

Antimicrobial Activity of Extracts from Leaves, Stems and Flowers of Euphorbia macroclada against plant pathogenic fungi

OpenAIRE

K. Al-Mughrabi

2003-01-01

Extracts drawn from dried and powdered flowers, stems and leaves of Euphorbia macroclada with some organic solvents were tested for antimicrobial effect against the fungi Verticillium dahliae, Fusarium oxysporum, Rhizopus stolonifer, Penicillium italicum, Rhizoctonia solani, Alternaria solani, Stemphylium solani, Cladosporium sp., Mucor sp., and Pythium sp. The strongest inhibitory effect of the extracts was observed against R. solani, V. dahliae, F. oxysporum, Pythium sp. and R. ...

Cucurbitane-type triterpenoids from the stems and leaves of Momordica charantia.

Science.gov (United States)

Zhao, Gao-Ting; Liu, Jie-Qing; Deng, Yuan-Yuan; Li, Hai-Zhou; Chen, Jian-Chao; Zhang, Zhi-Run; Zhou, Lin; Qiu, Ming-Hua

2014-06-01

Six new cucurbitane-type triterpenoids, karavilagenin F (1), karavilosides XII and XIII (2, 3), momordicines VI, VII, and VIII (4, 5 and 6), along with four known ones, 5β,19-epoxy-25-methoxycucurbita-6,23-diene-3β,19-diol (7), 5β,19-epoxycucurbita-6, 23-diene-3β,19,25-triol (8), kuguacin R (9), and (19R,23E)-5β,19-epoxy-19-methoxycucurbita-6,23,25-trien-3β-ol (10), were isolated from the stems and leaves of Momordica charantia L. Their chemical structures were elucidated by extensive 1D NMR and 2D NMR (HSQC, HMBC, COSY, and ROESY), MS experiments, and CD spectrum. Compound 6 showed weak cytotoxicity against five human cancer cells lines with IC50 values of 14.3-20.5μmol/L. Copyright © 2014 Elsevier B.V. All rights reserved.

Transcriptome analysis of phosphorus stress responsiveness in the seedlings of Dongxiang wild rice (Oryza rufipogon Griff.).

Science.gov (United States)

Deng, Qian-Wen; Luo, Xiang-Dong; Chen, Ya-Ling; Zhou, Yi; Zhang, Fan-Tao; Hu, Biao-Lin; Xie, Jian-Kun

2018-03-15

Low phosphorus availability is a major factor restricting rice growth. Dongxiang wild rice (Oryza rufipogon Griff.) has many useful genes lacking in cultivated rice, including stress resistance to phosphorus deficiency, cold, salt and drought, which is considered to be a precious germplasm resource for rice breeding. However, the molecular mechanism of regulation of phosphorus deficiency tolerance is not clear. In this study, cDNA libraries were constructed from the leaf and root tissues of phosphorus stressed and untreated Dongxiang wild rice seedlings, and transcriptome sequencing was performed with the goal of elucidating the molecular mechanisms involved in phosphorus stress response. The results indicated that 1184 transcripts were differentially expressed in the leaves (323 up-regulated and 861 down-regulated) and 986 transcripts were differentially expressed in the roots (756 up-regulated and 230 down-regulated). 43 genes were up-regulated both in leaves and roots, 38 genes were up-regulated in roots but down-regulated in leaves, and only 2 genes were down-regulated in roots but up-regulated in leaves. Among these differentially expressed genes, the detection of many transcription factors and functional genes demonstrated that multiple regulatory pathways were involved in phosphorus deficiency tolerance. Meanwhile, the differentially expressed genes were also annotated with gene ontology terms and key pathways via functional classification and Kyoto Encyclopedia of Gene and Genomes pathway mapping, respectively. A set of the most important candidate genes was then identified by combining the differentially expressed genes found in the present study with previously identified phosphorus deficiency tolerance quantitative trait loci. The present work provides abundant genomic information for functional dissection of the phosphorus deficiency resistance of Dongxiang wild rice, which will be help to understand the biological regulatory mechanisms of phosphorus

Leaf gas films contribute to rice (Oryza sativa) submergence tolerance during saline floods

DEFF Research Database (Denmark)

Herzog, Max; Konnerup, Dennis; Pedersen, Ole

2018-01-01

Floods and salinization of agricultural land adversely impact global rice production. We investigated whether gas films on leaves of submerged rice delay salt entry during saline submergence. Two-week-old plants with leaf gas films (+GF) or with gas films experimentally removed (-GF) were submerged...

Comparison of Effect of Brassinosteroid and Gibberellin Biosynthesis Inhibitors on Growth of Rice Seedlings

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Tadashi Matusmoto

2016-01-01

Full Text Available Brassinosteroid (BR and gibberellin (GA are two predominant plant hormones that regulate plant cell elongation. Mutants disrupt the biosynthesis of these hormones and display different degrees of dwarf phenotypes in rice. Although the role of each plant hormone in promoting the longitudinal growth of plants has been extensively studied using genetic methods, their relationship is still poorly understood. In this study, we used two specific inhibitors targeting BR and GA biosynthesis to investigate the roles of BR and GA in growth of rice seedlings. Yucaizol, a specific inhibitor of BR biosynthesis, and Trinexapac-ethyl, a commercially available inhibitor of GA biosynthesis, were used. The effect of Yucaizol on rice seedlings indicated that Yucaizol significantly retarded stem elongation. The IC50 value was found to be approximately 0.8 μmol/L. Yucaizol also induced small leaf angle phenocopy in rice seedlings, similarly to BR-deficient rice, while Trinexapac-ethyl did not. When Yucaizol combined with Trinexapac-ethyl was applied to the rice plants, the mixture of these two inhibitors retarded stem elongation of rice at lower doses. Our results suggest that the use of a BR biosynthesis inhibitor combined with a GA biosynthesis inhibitor may be useful in the development of new technologies for controlling rice plant height.

Association of Increased Grain Iron and Zinc Concentrations with Agro-morphological Traits of Biofortified Rice

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Laura Tatiana Moreno-Moyano

2016-09-01

Full Text Available Biofortification of rice (Oryza sativa L. with micronutrients is widely recognized as a sustainable strategy to alleviate human iron (Fe and zinc (Zn deficiencies in developing countries where rice is the staple food. Constitutive overexpression of the rice nicotianamine synthase (OsNAS genes has been successfully implemented to increase Fe and Zn concentrations in unpolished and polished rice grain. Intensive research is now needed to couple this high-micronutrient trait with high grain yields. We investigated associations of increased grain Fe and Zn concentrations with agro-morphological traits of backcross twice second filial (BC2F2 transgenic progeny carrying OsNAS1 or OsNAS2 overexpression constructs under indica/japonica and japonica/japonica genetic backgrounds. Thirteen agro-morphological traits were evaluated in BC2F2 transgenic progeny grown under hydroponic conditions. Concentrations of 8 mineral nutrients (Fe, Zn, copper, manganese, calcium, magnesium, potassium and phosphorus in roots, stems/sheaths, non-flag leaves, flag leaves, panicles and grain were also determined. A distance-based linear model (DistLM was utilized to extract plant tissue nutrient predictors accounting for the largest variation in agro-morphological traits differing between transgenic and non-transgenic progeny. Overall, the BC2F2 transgenic progeny contained up to 148% higher Fe and 336% higher Zn concentrations in unpolished grain compared to non-transgenic progeny. However, unpolished grain concentrations surpassing 23 µg Fe g-1 and 40 µg Zn g-1 in BC2F2 indica/japonica progeny, and 36 µg Fe g-1 and 56 µg Zn g1 in BC2F2 japonica/japonica progeny, were associated with significant reductions in grain yield. DistLM analyses identified grain-Zn and panicle-magnesium as the primary nutrient predictors associated with grain yield reductions in the indica/japonica and japonica/japonica progeny, respectively. We subsequently produced polished grain from high

Evaluation of rice genotypes to salt stress in different growth stages ...

African Journals Online (AJOL)

User

2012-05-15

May 15, 2012 ... 40 rice genotypes were screened in saline soil of electrical conductivity (EC) of 4, 8 and 12 ds/m in vegetative ... Plant growth, plant height or shoot biomass, were reported to .... biomass had positive effect on rice salinity tolerance. The .... Stem dry weight .... genotypes have more Na+ concentration in cells.

Low Temperature Storage of Southern Rice Black-Streaked Dwarf Virus-Infected Rice Plants Cannot Sustain Virus Transmission by the Vector.

Science.gov (United States)

Liu, Danfeng; Li, Pei; Han, Yongqiang; Lei, Wenbin; Hou, Maolin

2016-02-01

Southern rice black-streaked dwarf virus (SRBSDV) is a novel virus transmitted by white-backed planthopper Sogatella furcifera (Hováth) (Hemiptera: Delphacidae). Due to low virus transmission efficiency by the planthopper, researchers are frequently confronted with shortage of viruliferous vectors or infected rice plants, especially in winter and the following spring. To find new ways to maintain virus-infected materials, viral rice plants were stored at -80°C for 45 or 140 d and evaluated as virus sources in virus transmission by the vector. SRBSDV virions were not degraded during storage at -80°C as indicated by reverse transcription-polymerase chain reaction and reverse transcription real-time PCR detection. The planthopper nymphs fed on the infected thawed plants for 48 h survived at about 40% and showed positive detection of SRBSDV, but they lost the virus after feeding for another 20 d (the circulative transmission period) on noninfected plants. Transmission electron microscope images indicated broken capsid of virions in infected thawed leaves in contrast to integrity capsid of virions in infected fresh leaves. These results show that low temperature storage of SRBSDV-infected rice plants cannot sustain virus transmission by white-backed planthopper. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Mutation of Cellulose Synthase Gene Improves the Nutritive Value of Rice Straw

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Yanjing Su

2012-06-01

Full Text Available Rice straw is an important roughage resource for ruminants in many rice-producing countries. In this study, a rice brittle mutant (BM, mutation in OsCesA4, encoding cellulose synthase and its wild type (WT were employed to investigate the effects of a cellulose synthase gene mutation on rice straw morphological fractions, chemical composition, stem histological structure and in situ digestibility. The morphological fractions investigation showed that BM had a higher leaf sheath proportion (43.70% vs 38.21%, p0.05 was detected in neutral detergent fiber (NDFom and ADL contents for both strains. Histological structure observation indicated that BM stems had fewer sclerenchyma cells and a thinner sclerenchyma cell wall than WT. The results of in situ digestion showed that BM had higher DM, NDFom, cellulose and hemicellulose disappearance at 24 or 48 h of incubation (p<0.05. The effective digestibility of BM rice straw DM and NDFom was greater than that of WT (31.4% vs 26.7% for DM, 29.1% vs 24.3% for NDFom, p<0.05, but the rate of digestion of the slowly digested fraction of BM rice straw DM and NDF was decreased. These results indicated that the mutation in the cellulose synthase gene could improve the nutritive value of rice straw for ruminants.

Resistance of rice to insect pests mediated by suppression of serotonin biosynthesis.

Science.gov (United States)

Lu, Hai-Ping; Luo, Ting; Fu, Hao-Wei; Wang, Long; Tan, Yuan-Yuan; Huang, Jian-Zhong; Wang, Qing; Ye, Gong-Yin; Gatehouse, Angharad M R; Lou, Yong-Gen; Shu, Qing-Yao

2018-05-07

Rice is one of the world's most important foods, but its production suffers from insect pests, causing losses of billions of dollars, and extensive use of environmentally damaging pesticides for their control 1,2 . However, the molecular mechanisms of insect resistance remain elusive. Although a few resistance genes for planthopper have been cloned, no rice germplasm is resistant to stem borers. Here, we report that biosynthesis of serotonin, a neurotransmitter in mammals 3 , is induced by insect infestation in rice, and its suppression confers resistance to planthoppers and stem borers, the two most destructive pests of rice 2 . Serotonin and salicylic acid derive from chorismate 4 . In rice, the cytochrome P450 gene CYP71A1 encodes tryptamine 5-hydroxylase, which catalyses conversion of tryptamine to serotonin 5 . In susceptible wild-type rice, planthopper feeding induces biosynthesis of serotonin and salicylic acid, whereas in mutants with an inactivated CYP71A1 gene, no serotonin is produced, salicylic acid levels are higher and plants are more insect resistant. The addition of serotonin to the resistant rice mutant and other brown planthopper-resistant genotypes results in a loss of insect resistance. Similarly, serotonin supplementation in artificial diet enhances the performance of both insects. These insights demonstrate that regulation of serotonin biosynthesis plays an important role in defence, and may prove valuable for breeding insect-resistant cultivars of rice and other cereal crops.

Ancient rice cultivar extensively replaces phospholipids with non-phosphorus glycolipid under phosphorus deficiency.

Science.gov (United States)

Tawaraya, Keitaro; Honda, Soichiro; Cheng, Weiguo; Chuba, Masaru; Okazaki, Yozo; Saito, Kazuki; Oikawa, Akira; Maruyama, Hayato; Wasaki, Jun; Wagatsuma, Tadao

2018-02-07

Recycling of phosphorus (P) from P-containing metabolites is an adaptive strategy of plants to overcome soil P deficiency. This study was aimed at demonstrating differences in lipid remodelling between low-P-tolerant and -sensitive rice cultivars using lipidome profiling. The rice cultivars Akamai (low-P-tolerant) and Koshihikari (low-P-sensitive) were grown in a culture solution with [2 mg l -1 (+P)] or without (-P) phosphate for 21 and 28 days after transplantation. Upper and lower leaves were collected. Lipids were extracted from the leaves and their composition was analysed by liquid chromatography/mass spectrometry (LC-MS). Phospholipids, namely phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG) and phosphatidylinositol (PI), lysophosphatidylcholine (lysoPC), diacylglycerol (DAG), triacylglycerol (TAG) and glycolipids, namely sulfoquinovosyl diacylglycerol (SQDG), digalactosyldiacylglycerol (DGDG), monogalactosyldiacylglycerol (MGDG) and 1,2-diacyl-3-O-alpha-glucuronosyl glycerol (GlcADG), were detected. GlcADG level was higher in both cultivars grown in -P than in +P and the increase was larger in Akamai than in Koshihikari. DGDG, MGDG and SQDG levels were higher in Akamai grown in -P than in +P and the increase was larger in the upper leaves than in the lower leaves. PC, PE, PG and PI levels were lower in both cultivars grown in -P than in +P and the decrease was larger in the lower leaves than in the upper leaves and in Akamai than in Koshihikari. Akamai catabolised more phospholipids in older leaves and synthesised glycolipids in younger leaves. These results suggested that extensive phospholipid replacement with non-phosphorus glycolipids is a mechanism underlying low-P-tolerance in rice cultivars. © 2018 Scandinavian Plant Physiology Society.

Effects of Drying Temperature on Flavonoids Extraction Rate from Young Stems and Leaves of Two Cassava Varieties

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WANG Ding-mei

2017-01-01

Full Text Available To improve flavonoids resources utilization level of young cassava stems and leaves, using cassava varieties SC09 and SC205 as ob jects, investigated the effect of different drying temperatures(40~120℃on the flavonoids extraction rate(FERand their stability in 120 d storage period after drying, explored a right drying storage method for postharvest young cassava stems and leaves. The research showed that total FER rised first, and then fell and rised again with the increase of drying temperature. During 40~80℃, the total FER was obviously in fluenced by variety and temperature, but only temperature was main factor affecting total FER during 90~120℃. Extract degree of flavonoids include rutin, amentoflavone or catechin, kaempferol, hesperidin, quercetin minished in order; the effect of cassava variety on the extraction rate of catechin and hesperidin was greater than that of drying temperature, but that contrary to other 4 flavonoids. Variety and temperature had a maximum impact respectively on catechin and rutin extraction rates. Whereas both of variety and temperature had a minimum impact on kaempferol extraction rate. FER reached higher levels of 1.42%and 1.53% respectively in SC09 after 120℃drying and SC205 after 110℃drying, and had best stability during 120 d storage period. The extraction rate of hesperidin increased after drying storage, and that of other 5 ingredients were changing with different varieties and temperatures; the coefficient variation(CV=1.03%~6.86%of kaempferol was minimum and its stability was best; extraction rates of rutin and kaempferol in SC205 after 110℃drying were maximum, whose increasing rates were 44.89%and 7.27%respectively with a small separate degree(CV were 6.94%, 4.59%and good extraction stability. Maximum in creasing rates of catechin, amentoflavone, quercetin and hesperidin were 211.60%，17.60%，186.39% and 538.08% respectively. However,their stabilities of extraction efficiency were poor

Laser induced fluorescence of some plant leaves

International Nuclear Information System (INIS)

Helmi, M.S.; Mohamed, M.M.; Amer, R.; Elshazly, O.; Elraey, M.

1992-01-01

Laser induced fluorescence (LIF) is successfully used as a technique for remote detection of spectral characteristics of some plants. A pulsed nitrogen laser at 337.1 nm is used to excite cotton, corn and rice leaves. The fluorescence spectrum is detected in the range from 340 nm to 820 nm. It is found that, these plant leaves have common fluorescence maxima at 440 nm, 685 nm and 740 nm. plant leaves are also found to be identifiable by the ratio of the fluorescence intensity at 440 nm to that at 685 nm. The present technique can be further used as a means of assessing, remotely, plant stresses. 5 fig

Eficiência de Metarhizium anisopliae no controle do Percevejo-do-Colmo Tibraca limbativentris (Heteroptera: Pentatomidae em lavoura de arroz irrigado Efficiency of Metarhizium anisopliae on rice stem bug Tibraca limbativentris (Heteroptera: Pentatomidae control in flooded rice field

Directory of Open Access Journals (Sweden)

José Francisco da Silva Martins

2004-12-01

, pode provavelmente reduzir a taxa de disseminação do fungo nos arrozais e, por conseqüência, ser desfavorável à ocorrência de epizootias.The rice stem bug, Tibraca limbativentris Stal, 1860 (Heteroptera: Pentatomidae, is an important pest of rice (Oryza sativa L. in Brazil, mainly in flooded system of cultivation. The effect of two ways of application (conidia in aqueous suspension and on rice grain of Metarhizium anisopliae strain 172 for the control of the rice stem bug, was evaluated in three experiments conducted in 1991, 1992 and 1994 in commercial irrigated rice. In 1991, the spraying of conidia suspension and manual distribution of rice grain covered with fungal material at dose of 7.2 x 10(13 conidia.ha-1, on soil and among rice stems, where the bugs were located, reduced significantly the insect natural population with control efficiencies of 52.6 and 61.8%, respectively. Studies about establishment and persistence of fungal conidia in soil, using the colony forming unity (CFU counts, indicated that the fungus persisted in the soil between two rice crop seasons, up to 216 days after application, when new rice crops were established. The number of CFU was greater in the plots treated with rice grain covered with fungal material. The linear growth of CFU in the control plots showed that the fungus spread to the untreated areas of the rice field. Significant control efficiency was obtained in 1993 for grain and aqueous fungus treatment with 48.2% and 51.8%, respectively. In 1994, the conidial suspension at dose of 5x10(13 conidia.ha-1 resulted in control efficiency of 39.5%. The level of insect mycosis, however, was low in both 1993 and 1994, reaching a maximum of 20% mycosis in 1993. The low numbers of insect with mycosis compared with the level of mortality, may probably reduce the rate of fungal dissemination in rice fields and, consequently, be detrimental to the occurrence of epizootics.

The Utilization of Bottom Ash Coal for Briquette Products by Adding Teak Leaves Charcoal, Coconut Shell Charcoal, and Rice Husk Charcoal

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Syafrudin Syafrudin

2015-01-01

Full Text Available The limitations of the availability of energy sources especially fuel oil has become a serious threat for the society. The use of coal for energy source as the replacement of fuel oil, in one hand, is very profitable, but on the other hand, will cause problem which is the coal ash residue. This coal ash is a by-product of coal combustion. This coal ash contains bottom ash. Through this observation, the bottom ash can be processed to be charcoal if added by teak leaves, coconut shell, and rice husk. Also, this observation needs to add binder materials for further processing in order to form briquette. It can be used as alternative fuel, the utilization of bottom ash and biomass will give positive impact to the environment. This observation was conducted by using compositions such as bottom ash, teak leaves, coconut shell, and rice husk. The treatment was using comparison 100%:0% ; 80%:20% ; 60%:40% ; 50%:50% ; 40%:60% ; 20%:80% ; 0%:100%. The result that the best briquette was on the composition of 20% bottom ash : 80% coconut shell. The characteristic values from that composition were moisture content of 3.45%, ash content of 17,32%, calorific value of 7.945,72 Cal/gr, compressive strength of 2,18 kg/cm2, level of CO of 105 mg/m3, and heavy metals Cu of 29,83 µg/g and  Zn 32,99 µg/g. The characteristic value from each briquette composition treatment showed that the increasing usage proportion of biomass as added material for briquette was able to increase its moisture content and calorific value. Besides, it is also able to decrease its ash content and compressive strength

Isolation and characterization of a Ds-tagged rice (Oryza sativa L.) GA-responsive dwarf mutant defective in an early step of the gibberellin biosynthesis pathway.

Science.gov (United States)

Margis-Pinheiro, Marcia; Zhou, Xue-Rong; Zhu, Qian-Hao; Dennis, Elizabeth S; Upadhyaya, Narayana M

2005-03-01

We have isolated a severe dwarf transposon (Ds) insertion mutant in rice (Oryza sativa L.), which could be differentiated early in the seedling stage by reduced shoot growth and dark green leaves, and later by severe dwarfism and failure to initiate flowering. These mutants, however, showed normal seed germination and root growth. One of the sequences flanking Ds, rescued from the mutant, was of a chromosome 4-located putative ent-kaurene synthase (KS) gene, encoding the enzyme catalyzing the second step of the gibberellin (GA) biosynthesis pathway. Dwarf mutants were always homozygous for this Ds insertion and no normal plants homozygous for this mutation were recovered in the segregating progeny, indicating that the Ds insertion mutation is recessive. As mutations in three recently reported rice GA-responsive dwarf mutant alleles and the dwarf mutation identified in this study mapped to the same locus, we designate the corresponding gene OsKS1. The osks1 mutant seedlings were responsive to exogenous gibberellin (GA3). OsKS1 transcripts of about 2.3 kb were detected in leaves and stem of wild-type plants, but not in germinating seeds or roots, suggesting that OsKS1 is not involved in germination or root growth. There are at least five OsKS1-like genes in the rice genome, four of which are also represented in rice expressed sequence tag (EST) databases. All OsKS1-like genes are transcribed with different expression patterns. ESTs corresponding to all six OsKS genes are represented in other cereal databases including barley, wheat and maize, suggesting that they are biologically active.

Integrating Soil Silicon Amendment into Management Programs for Insect Pests of Drill-Seeded Rice.

Science.gov (United States)

Villegas, James M; Way, Michael O; Pearson, Rebecca A; Stout, Michael J

2017-08-13

Silicon soil amendment has been shown to enhance plant defenses against insect pests. Rice is a silicon-accumulating graminaceous plant. In the southern United States, the rice water weevil and stem borers are important pests of rice. Current management tactics for these pests rely heavily on the use of insecticides. This study evaluated the effects of silicon amendment when combined with current management tactics for these rice insect pests in the field. Field experiments were conducted from 2013 to 2015. Rice was drill-planted in plots subjected to factorial combinations of variety (conventional and hybrid), chlorantraniliprole seed treatment (treated and untreated), and silicon amendment (treated and untreated). Silicon amendment reduced densities of weevil larvae on a single sampling date in 2014, but did not affect densities of whiteheads caused by stem borers. In contrast, insecticidal seed treatment strongly reduced densities of both weevil larvae and whiteheads. Higher densities of weevil larvae were also observed in the hybrid variety in 2014, while higher incidences of whiteheads were observed in the conventional variety in 2014 and 2015. Silicon amendment improved rice yields, as did chlorantraniliprole seed treatment and use of the hybrid variety.

Growth inhibition and effect on photosystem by three imidazolium chloride ionic liquids in rice seedlings

Energy Technology Data Exchange (ETDEWEB)

Liu, Huijun, E-mail: lhj@mail.zjgsu.edu.cn [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province (China); Zhang, Shuxian [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province (China); Jiaxing University, Jiaxing 314001, Zhejiang Province (China); Zhang, Xiaoqiang; Chen, Caidong [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang Province (China)

2015-04-09

Highlights: • The three ILs have phytotoxic on rice growth. • The antioxidant enzyme activities increased first and then declined with ILs concentration increased. • The Hill reaction activity decreased and the PS II of leaves was damaged by ILs. • The toxicity of ILs increased as the alkyl chain length increased as the order: [OMIM]Cl < [DMIM]Cl < [C{sub 12}MIM]Cl. - Abstract: The effects of three imidazolium chloride ionic liquids (ILs) including 1-octyl-3-methylimidazolium chloride ionic liquid ([OMIM]Cl), 1-decyl-3-methylimidazolium chloride ionic liquid ([DMIM]Cl) and 1-dodecyl-3-methylimidazolium chloride ionic liquid ([C{sub 12}MIM]Cl) were studied in hydroponically grown rice seedlings. The growth inhibition rate increased and the Hill reaction activity of isolated rice chloroplasts decreased with increasing ILs concentrations. The IC{sub 50,5d} for stem length was 0.70 mg/L of [OMIM]Cl, 0.15 mg/L of [DMIM]Cl, and 0.055 mg/L of [C{sub 12}MIM]Cl, respectively. The SOD, POD and CAT activities of chloroplast exhibited initial increases followed by decreases in activity with increasing ILs concentrations. Chlorophyll fluorescence parameters such as the maximum effective quantum yield of PSII(F{sub v}/F{sub m}), the potential activity of PSII(F{sub v}/F{sub 0}), the yield of photochemical quantum [Y(II)], the photochemical quenching coefficient (qP), the non-photochemical quenching coefficient (NPQ) and the relative electron transport ratio (rETR) were affected, showing that ILs will damage the PSII. The results demonstrated that imidazolium chloride ILs are phytotoxic to rice growth and their photosystem, the toxicity increased as the alkyl chain length increased with the following order: [OMIM]Cl < [DMIM]Cl < [C{sub 12}MIM]Cl. The results will help to better understand the possible role of the defense mechanism in rice caused by ILs exposure.

Evaluation of the larvicidal efficiency of stem, roots and leaves of the weed, Parthenium hysterophorus (Family: Asteraceae against Aedes aegypti L.

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Sarita Kumar

2012-10-01

Full Text Available Objective: To assess the larvicidal potential of various extracts prepared from the stem, roots and leaves of Parthenium hysterophorus (P. hysterophorus against 3rd and 4th instars of Aedes aegypti (Ae. aegypti. Methods: The extracts from each part were prepared with four solvents; petroleum ether, hexane, acetone and diethyl ether. Each part was dried, powdered and soaked in different solvents, separately, for five days. The crude extracts thus formed were concentrated using rotary evaporator and stored as stock solution of 1 000 mg/L. Results: All the extracts prepared from the leaves were found ineffective against both the instars causing only 10%-40% mortality. Against 3rd instars, the hexane and petroleum ether extracts prepared from the stem of P. hysterophorus were found effective exhibiting LC50 values of 379.76 and 438.57 mg/L, respectively. Likewise the hexane and petroleum ether extracts from the Parthenium roots resulted in LC50 values of 432.38 and 562.50 mg/L, respectively, against 4th instars of Ae. aegypti revealing their larvicidal potential. It was further found that the hexane extracts, whether from roots or stem, were 13-28% more effective than the petroleum ether extracts. The qualitative phytochemical study of the effective extracts from the stems and roots showed the presence of alkaloids, saponins, terpenoids and flavonoids in different combinations. Conclusions: Our investigations demonstrated the potential of P. hysterophorus roots and stems against Ae. aegypti larvae and their benefits as new types of mosquito larvicides. Variety of types and levels of active constituents in each kind of extract may be responsible for the variability in their potential against Ae. aegypti. Further research is needed to identify these components.

Radioactive cesium deposition on rice, wheat, peach tree and soil after nuclear accident in Fukushima

International Nuclear Information System (INIS)

Nakanishi, T.M.; Kobayashi, N.I.; Tanoi, K.

2013-01-01

We present how radioactive Cs was deposited on wheat, rice, peach tree and soil after nuclear accident in Fukushima. The deposition of radioactive Cs was found as spots at the surface of the leaves, branch or trunk of the trees, as well as in soil using one of the imaging method, autoradiography. The deposited radioactive Cs was not easily washed out, even with the treatment of acid solution. When the wheat was harvested 2 months after the accident, high radioactivity of Cs was found only on the leaves developed and expanded at the time of the accident. In the case of the rice grain, most of the radioactivity was found in bran and the radioactivity was drastically reduced in milled rice. Most of the radioactive Cs accumulation in rice plants was estimated from the absorption of the Cs ion dissolved in water, rather than Cs adsorbed in soil. (author)

Prediction of tritium behavior in rice plant after a short-term exposure of HTO

International Nuclear Information System (INIS)

Yook, Dae Sik; Lee, Kun Jai; Choi, Heui Joo; Lee, Chang Min

2001-01-01

In many Asian countries including Korea, rice is a very important food crop. Its grain is consumed by humans and its straw is used to feed animals. Because four CANDU reactors are in operation in Korea, relatively large amounts of tritium are released into the environment and the dose by these tritium in the rice plant must be estimated. Since 1997, KAERI (Korea Atomic Energy Research Institute) has carried out experimental studies to obtain domestic data on various parameters related to the direct tritium contamination of plant. But the analysis of the tritium behavior in the rice plant has been insufficient. In this study, the behavior of the tritium in the rice plant is predicted and compared with the measurement performed at KAERI. Using the conceptual model of the soil-plant-atmosphere tritiated water transport system which was suggested by Charles E. Murphy, transient tritium concentrations in soil and leaves were predicted. If the effect of tritium concentration in the soil is taken into account, the tritium concentration in leaves can be described by a double exponential model, however if the tritium concentration in the soil is disregarded, the tritium concentration in leaves can be described by a single exponential term like other relevant models e.g. UFOTRI or STAR-H3 model. The results can be used to predict the tritium concentration in the rice plant near the plant site and to estimate the ingestion dose after the release of tritium to the environment

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)

Effects of Exposion to Fine Particles of Pb and Cd on Early Growth of Rice and Potatoes

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YANG Fan

2017-08-01

Full Text Available Heavy metal-containing particles in the atmosphere have negative impacts on the seedling growth and early stage growth of terrestrial plants. Exposure scenarios were established to simulate the ambient conditions with different pollution levels of airborne heavy metals. Under these scenarios, hazardous impacts of fine particles containing lead(Pb and cadmium(Cd on the emergence, seedling growth, and fresh weight(including both above ground stem leaf of rice and underground stem tuber of potato were evaluated. The results showed that, for exposure treatment groups, the concentrations of Pb and Cd in the artificial soil increased at the end of the test. Compared with the background value in soil, the Cd level elevated about 8.8 times while no significant increase was observed for Pb concentration. The accumulation values of Pb and Cd were 0.002 0, 0.054 mg·kg-1 in the stem leaf of rice and 0.185 0, 0.074 mg·kg-1 in the stem tuber of potato. The exposure had no significant inhibition effect on all the biomass endpoints of rice, but had an inhibition rate of 27% on the fresh weight of potato underground stem tuber. Thus, under the simulation exposure, larger impact was projected to the Cd concentration in the artificial soil, and the Cd accumulative effect was more obvious in the underground stem tuber of potatoes. Compared with the control groups, the combined pollution of Pb and Cd in the exposure treatment groups indicated remarkable inhibition and stress effects. Moreover, aboveground stem leaf of rice showed better adaption and low sensitivity when exposed to pollutants at certain concentrations.

The components of rice and watermelon root exudates and their effects on pathogenic fungus and watermelon defense.

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Ren, Lixuan; Huo, Hongwei; Zhang, Fang; Hao, Wenya; Xiao, Liang; Dong, Caixia; Xu, Guohua

2016-06-02

Watermelon (Citrullus lanatus) is susceptible to wilt disease caused by the fungus Fusarium oxysporum f. sp niveum (FON). Intercropping management of watermelon/aerobic rice (Oryza sativa) alleviates watermelon wilt disease, because some unidentified component(s) in rice root exudates suppress FON sporulation and spore germination. Here, we show that the phenolic acid p-coumaric acid is present in rice root exudates only, and it inhibits FON spore germination and sporulation. We found that exogenously applied p-coumaric acid up-regulated the expression of ClPR3 in roots, as well as increased chitinase activity in leaves. Furthermore, exogenously applied p-coumaric acid increased β-1,3-glucanase activity in watermelon roots. By contrast, we found that ferulic acid was secreted by watermelon roots, but not by rice roots, and that it stimulated spore germination and sporulation of FON. Exogenous application of ferulic acid down-regulated ClPR3 expression and inhibited chitinase activity in watermelon leaves. Salicylic acid was detected in both watermelon and rice root exudates, which stimulated FON spore germination at low concentrations and suppressed spore germination at high concentrations. Exogenously applied salicylic acid did not alter ClPR3 expression, but did increase chitinase and β-1,3-glucanase activities in watermelon leaves. Together, our results show that the root exudates of phenolic acids were different between rice and watermelon, which lead to their special ecological roles on pathogenic fungus and watermelon defense.

What make them leave and where do they go?

DEFF Research Database (Denmark)

Ulriksen, Lars; Madsen, Lene Møller; Holmegaard, Henriette Tolstrup

2015-01-01

This chapter presents the results of a quantitative analysis of national data covering Danish students who in the period 1995-2009 completed an uppersecondary school programme and entered a higher-education science, technology, engineering or mathematics (STEM) programme. The analysis focuses...... chance of a male or female student entering a STEM programme. The results suggest that female students are more affected by achieving a high grade-point average and by the educational background of their parents than are the male students. The relative risk of non-completion is higher for women than...... on identifying variables that change the hazard ratio for (1) entering a STEM programme and (2) leaving a STEM programme without completing it. Finally, the chapter explores (3) the destinations of students who leave a STEM higher-education programme. It is found that there has been no change in the relative...

[Hyperspectral remote sensing diagnosis models of rice plant nitrogen nutritional status].

Science.gov (United States)

Tan, Chang-Wei; Zhou, Qing-Bo; Qi, La; Zhuang, Heng-Yang

2008-06-01

The correlations of rice plant nitrogen content with raw hyperspectral reflectance, first derivative hyperspectral reflectance, and hyperspectral characteristic parameters were analyzed, and the hyperspectral remote sensing diagnosis models of rice plant nitrogen nutritional status with these remote sensing parameters as independent variables were constructed and validated. The results indicated that the nitrogen content in rice plant organs had a variation trend of stem plant nitrogen nutritional status, with the decisive coefficients (R2) being 0.7996 and 0.8606, respectively; while the model with vegetation index (SDr - SDb) / (SDr + SDb) as independent variable, i. e., y = 365.871 + 639.323 ((SDr - SDb) / (SDr + SDb)), was most fit rice plant nitrogen content, with R2 = 0.8755, RMSE = 0.2372 and relative error = 11.36%, being able to quantitatively diagnose the nitrogen nutritional status of rice.

Fertilizer-n uptake and distribution in rice plants using 15N tracer technique

International Nuclear Information System (INIS)

Yan Juan; Shen Qirong; Yin Bin; Wan Xinjun

2009-01-01

Fertilizer-nitrogen (N) uptake and distribution in rice were studied using 15 N tracer technique. The results obtained were as follows. At the tillering, jointing and booting, and anthesis stages, 23.1%, 8.3% and 19.9% of N were taken from fertilizer applied in base (N1), tillering (N2) and jointing and booting (N3), respectively. The 15 N translocation from anthesis to maturity was in the order of N3>N1>N2, but the 15 N translocation efficiency was higher in N1 (base fertilizer treatment) than in the other two treatments. At maturity, the 15 N distribution in straw in the treatments of N1, N2 and N3 was only 24.3%, 26.7% and 30.4%, respectively. No matter what time the N fertilizer was applied, the 15 N uptake was mostly distributed in leaves, then in the sheath, the least in stem, and 15 N distribution in spike increased with the increased 15 N translocation from nutritional organs to spike after anthesis. The study also showed that the 15 N uptake at maturity in N1, N2 and N3 treatments was 10.3%, 5.9% and 12.4%, respectively. The results indicated that (1) when soil N content was not high, the base fertilizer application was important to rice growth, and optimal increment might help increase tillering, and improve rice quality; (2) the initiation fertilizer significantly promoted quantities during grain filling, and thus application of N fertilizer in initiation was of considerable advance in increasing N harvest index (NHI); (3) the rice plants absorbed less N applied in tillering stage due to a big N loss in that period. Therefore a little bit increase of base N fertilizer with no or very small amount of tillering fertilizer, together with some topdressing of N fertilizer during initiation could improve N uptake by rice. (authors)

Leaf application of silicic acid to upland rice and corn

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Carlos Alexandre Costa Crusciol

2013-12-01

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

Patatin-related phospholipase A, pPLAIIIα, modulates the longitudinal growth of vegetative tissues and seeds in rice.

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Liu, Guangmeng; Zhang, Ke; Ai, Jun; Deng, Xianjun; Hong, Yueyun; Wang, Xuemin

2015-11-01

Patatin-related phospholipase A (pPLA) hydrolyses glycerolipids to produce fatty acids and lysoglycerolipids. The Oryza sativa genome has 21 putative pPLAs that are grouped into five subfamilies. Overexpression of OspPLAIIIα resulted in a dwarf phenotype with decreased length of rice stems, roots, leaves, seeds, panicles, and seeds, whereas OspPLAIIIα-knockout plants had longer panicles and seeds. OspPLAIIIα-overexpressing plants were less sensitive than wild-type and knockout plants to gibberellin-promoted seedling elongation. OspPLAIIIα overexpression and knockout had an opposite effect on the expression of the growth repressor SLENDER1 in the gibberellin signalling process. OspPLAIIIα-overexpressing plants had decreased mechanical strength and cellulose content, but exhibited increases in the expression of several cellulose synthase genes. These results indicate that OspPLAIIIα plays a role in rice vegetative and reproductive growth and that the constitutive, high activity of OspPLAIIIα suppresses cell elongation. The decreased gibberellin response in overexpressing plants is probably a result of the decreased ability to make cellulose for anisotropic cell expansion. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Excessive sulfur supply reduces cadmium accumulation in brown rice (Oryza sativa L.)

International Nuclear Information System (INIS)

Fan Jianling; Hu Zhengyi; Ziadi, Noura; Xia Xu; Wu Congyanghui

2010-01-01

Human activities have resulted in cadmium (Cd) and sulfur (S) accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of excessive S supply on iron plaque formation and Cd accumulation in rice plants, using two Cd levels (0, 1.5 mg kg -1 ) combined with three S concentrations (0, 60, 120 mg kg -1 ). The results showed that excessive S supply significantly decreased Cd accumulation in brown rice due to the decrease of Cd availability and the increase of glutathione in rice leaves. But excessive S supply obviously increased Cd accumulation in roots due to the decrease of iron plaque formation on the root surface of rice. Therefore, excessive S supply may result in loss of rice yield, but it could effectively reduce Cd accumulation in brown rice exposed to Cd contaminated soils. - Excessive sulfur reduces cadmium accumulation in brown rice.

Exogenous superoxide dismutase may lose its antidotal ability on rice leaves

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Leaf diffusates of the resistant rice cultivars suppressed spore germination of blast fungus (Magnaporthe grisea). Bovine Cu-Zn superoxide dismutase (SOD) added to the diffusate abolished its toxicity. However, the enzyme added to the inoculum did not affect the toxicity of the diffusate. Even the s...

Antioxidant and immunomodulatory properties of polysaccharides from Allanblackia floribunda Oliv stem bark and Chromolaena odorata (L.) King and H.E. Robins leaves.

Science.gov (United States)

Boudjeko, Thaddée; Megnekou, Rosette; Woguia, Alice Louise; Kegne, Francine Mediesse; Ngomoyogoli, Judith Emery Kanemoto; Tchapoum, Christiane Danielle Nounga; Koum, Olga

2015-12-09

Many plant polysaccharides have shown high antioxidant and immunostimulating properties and can be explored as novel molecules with biological properties that can potentially improve immune function. The objective of this work was to characterize soluble and cell wall polysaccharides isolated from the stem bark of Allanblackia floribunda and Chromolaena odorata leaves and to evaluate their antioxidant and immunomodulatory properties. Three polysaccharide fractions: soluble polysaccharides (PoS), pectins (Pec) and hemicelluloses (Hem) were extracted from A. floribunda stem bark and C. odorata leaves. These samples were analysed for their proteins, phenolic compounds and total sugar contents. The monosaccharide composition was determined by gas chromatography and arabinogalactan proteins content in PoS was evaluated by rocket electrophoresis. The in vitro antioxidant activities were evaluated by 1, 1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2'-azino-bis-3-éthylbenzylthiazoline-6-sulphonic acid (ABTS) radical scavenging assays and ferrous ions chelating activity. Immunomodulatory activities were performed on the peripheral blood mononuclear cells (PBMCs) using proliferation and enzyme linked immunospot (ELISPOT) method to determine the production of an interferon-gamma. The characterization of the various fractions showed varied metabolites in each plant. In PoS fractions, Ara and Gal were the major monosaccharides found, indicating that arabinogalactans are the primary macromolecules. Hem fractions contained predominantly Xyl and GalA for A. floribunda and Xyl (upto 80 %) for and C. odorata. A. floribunda Hem fraction and C. odorata PoS fraction showed significant DPPH and ABTS radical scavenging activities and immunostimulatory activity via stimulation of PBMC and production of IFN-γ in a dose-dependent manner. The results obtained from this study support the ethnomedicinal use of the stem bark of A. floribunda and leaves of C. odorata. Further research is

What's So Special about STEM? A Comparison of Women's Retention in STEM and Professional Occupations.

Science.gov (United States)

Glass, Jennifer L; Sassler, Sharon; Levitte, Yael; Michelmore, Katherine M

2013-01-01

We follow female college graduates in the National Longitudinal Survey of Youth 1979 and compare the trajectories of women in science, technology, engineering, and mathematics (STEM)-related occupations to other professional occupations. Results show that women in STEM occupations are significantly more likely to leave their occupational field than professional women, especially early in their career, while few women in either group leave jobs to exit the labor force. Family factors cannot account for the differential loss of STEM workers compared to other professional workers. Few differences in job characteristics emerge either, so these cannot account for the disproportionate loss of STEM workers. What does emerge is that investments and job rewards that generally stimulate field commitment, such as advanced training and high job satisfaction, fail to build commitment among women in STEM.

Growth and Productivity of Response of Hybrid Rice to Application of Animal Manures, Plant Residues and Phosphorus

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Dr. Amanullah

2016-10-01

Full Text Available The objective of this research was to evaluate the impact of organic sources (animal manures vs. plant residues at the rate of 10 t ha-1 each on the productivity profitability of small land rice (Oryza sativa L. grower under different levels of phosphorus (0, 30, 60 and 90 kg P ha-1 fertilization. Two separate field experiments were conducted. In experiment (1, impact of three animal manures sources (cattle, sheep & poultry manures and P levels was studied along with one control plot (no animal manure and P applied as check was investigated. In experiment (2, three plant residues sources (peach leaves, garlic residues & wheat straw and P levels was studied along with one control plot (no plant residues and P applied as check. Both the experiments were carried out on small land farmer field at District Swabi, Khyber Pakhtunkhwa Province (Northwest Pakistan during summer 2015. The results revealed that in both experiments the control plot had significantly (p≤0.05 less productivity than the average of all treated plots with organic sources and P level. The increase in P levels in both experiments (animal manure vs. plant residues had resulted in higher rice productivity (90 = 60 > 30 > 0 kg P ha-1. In the experiment under animal manures, application of poultry manure increased rice productivity as compared with sheep and cattle manures (poultry > sheep > cattle manures. In the experiment under plant residues, application of peach leaves or garlic resides had higher rice productivity over wheat straw (peach leaves = garlic residues > wheat straw. On the average, the rice grown under animal manures produced about 20% higher grain yield than the rice grown under crop residues. We concluded from this study that application of 90 kg P ha-1 along with combined application of animal manures especially poultry manure could increase rice productivity. We conclude from this study that application of 90 kg P ha-1 along with combined application of animal

Cytological and molecular analysis of nonhost resistance in rice to wheat powdery mildew and leaf rust pathogens.

Science.gov (United States)

Cheng, Yulin; Yao, Juanni; Zhang, Hongchang; Huang, Lili; Kang, Zhensheng

2015-07-01

Cereal powdery mildews caused by Blumeria graminis and cereal rusts caused by Puccinia spp. are constant disease threats that limit the production of almost all important cereal crops. Rice is an intensively grown agricultural cereal that is atypical because of its immunity to all powdery mildew and rust fungi. We analyzed the nonhost interactions between rice and the wheat powdery mildew fungus B. graminis f. sp. tritici (Bgt) and the wheat leaf rust fungus Puccinia triticina (Ptr) to identify the basis of nonhost resistance (NHR) in rice against cereal powdery mildew and rust fungi at cytological and molecular levels. No visible symptoms were observed on rice leaves inoculated with Bgt or Ptr. Microscopic observations showed that both pathogens exhibited aberrant differentiation and significantly reduced penetration frequencies on rice compared to wheat. The development of Bgt and Ptr was also completely arrested at early infection stages in cases of successful penetration into rice leaves. Attempted infection of rice by Bgt and Ptr induced similar defense responses, including callose deposition, accumulation of reactive oxygen species, and hypersensitive response in rice epidermal and mesophyll cells, respectively. Furthermore, a set of defense-related genes were upregulated in rice against Bgt and Ptr infection. Rice is an excellent monocot model for genetic and molecular studies. Therefore, our results demonstrate that rice is a useful model to study the mechanisms of NHR to cereal powdery mildew and rust fungi, which provides useful information for the development of novel and durable strategies to control these important pathogens.

In vitro antioxidant activity, phenolic compounds and protective effect against DNA damage provided by leaves, stems and flowers of Portulaca oleracea (Purslane).

Science.gov (United States)

Silva, Rúben; Carvalho, Isabel S

2014-01-01

This study analyzed the antioxidant properties of Portulaca oleracea L., known as purslane. The samples (leaves, flowers and stems) were collected at two different locations in Portugal: Tavira (L1) and Vendas Novas (L2). Assays for total antioxidant activity, total phenolic content and ferric-reducing antioxidant power were conducted and, for both locations, significantly higher values (P < 0.05) were observed for stems (508.8 and 982.3 mg AAE/100 g DW, 1008.6 and 2285.5 mg GAE/100 g DW, 121.0 and 166.3 mg TE/100 g DW, respectively for each location), than in leaves or flowers. In the DPPH assay, the three-plant parts from L2 reached the 50% inhibition rate in lower concentrations than plants from L1. On the other hand, higher concentrations of total monomeric anthocyanins were found in samples from L1 (95.5, 88.8 and 86.0 mg/L) than in samples from L2 (81.7, 70.5 and 59.8 mg/L). The same was true for phenolic acids, estimated by liquid-chromatography, where methanol extracts were used. Phenolic extracts from all three-plant parts from both locations showed protective effects on DNA against hydroxyl radicals. This work suggests the possibility of benefit to human health from its consumption, related to the high antioxidant activity of purslane, even the stems, usually discarded in daily consumption.

Effect of root and leaf applications of soluble silicon on blast development in rice

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Isaias Severino Cacique

2013-01-01

Full Text Available Blast, caused by Pyricularia oryzae, is the most important fungal disease of rice worldwide. This study aimed to compare root and foliar supply of soluble silicon (Si on rice resistance to blast. The application of soluble Si to the roots increased Si concentration in leaf tissues as compare to plants grown in soil amended with calcium silicate. There was no increase in leaf Si concentration after soluble Si spray, regardless if the leaves were washed or not before analysis. X-ray microanalysis revealed that Si deposition was very similar on the leaf epidermis of plants sprayed with soluble Si, root amended with soluble Si or grown in soil amended with calcium silicate. The lesion size, the number of lesions per cm² of leaf and the area under blast progress curve were reduced for rice plants grown in soil that received the application of soluble Si or was amended with calcium silicate. The results of this study showed that the supply of soluble Si to the roots or its spray onto to the rice leaves can decrease blast symptoms.

Modeling the relationship between water level, wild rice abundance, and waterfowl abundance at a central North American wetland

Science.gov (United States)

Aagaard, Kevin; Eash, Josh D.; Ford, Walt; Heglund, Patricia J.; McDowell, Michelle; Thogmartin, Wayne E.

2018-01-01

Recent evidence suggests wild rice (Zizania palustris), an important resource for migrating waterfowl, is declining in parts of central North America, providing motivation to rigorously quantify the relationship between waterfowl and wild rice. A hierarchical mixed-effects model was applied to data on waterfowl abundance for 16 species, wild rice stem density, and two measures of water depth (true water depth at vegetation sampling locations and water surface elevation). Results provide evidence for an effect of true water depth (TWD) on wild rice abundance (posterior mean estimate for TWD coefficient, β TWD = 0.92, 95% confidence interval = 0.11—1.74), but not for an effect of wild rice stem density or water surface elevation on local waterfowl abundance (posterior mean values for relevant parameters overlapped 0). Refined protocols for sampling design and more consistent sampling frequency to increase data quality should be pursued to overcome issues that may have obfuscated relationships evaluated here.

In planta assay of hygromycin susceptibility and mutant screening in rice at heading stage

International Nuclear Information System (INIS)

Fu Haowei; Li Youfa; Ma Xinghua; Shen Shengquan; Shu Xiaoli; Shu Qingyao; Chen Yang

2012-01-01

Cells and tissue of plants carrying the hygromycin phosphotransferase gene (HPT) are tolerant to antibiotic hygromycin and hence become the common selection gene for genetic transformation of crop plants, particularly monocots. The present study aimed at establishing a rapid method for in planta screening of hygromycin tolerant plants in transgenic breeding. At heading stage transgenic and conventional rice plants were sprayed with hygromycin solutions of different concentrations (25 ∼ 100 mg/L) and toxic symptoms were observed in the following days. It was observed that yellow-brown necrotic spots appeared in the leaves and grains of conventional rice varieties after foliar spraying of 50 mg/L hygromycin, and the more spots were occurred with the higher hygromycin solution. There were 21.1 and 19.2 spots per cm 2 on flag leaves of indica varieties Jiayou 99 and C10, respectively; while 27.6% and 23.5% grains were yellow-brown in the varieties, respectively. The corresponding data for two japonica varieties Jiayou 5 and R5 were 11.8 and 10.7 for leave spots and 11.2% and 11.6% for yellow-brown grains, respectively. These results indicated that the two indica varieties are more sensitive to hygromycin than the two japonica varieties. In the treatment of hygromycin with above levels, the transgenic rice line KMD1 with the HPT gene showed no toxic symptoms on leaf or panicles. The γ-rays treated M 2 population of KMD1 was sprayed with 100 mg/L hygromycin solution at heading stage and 42 plants were screened out with toxic symptoms in leaves and panicles form 120000 plants. Among the 42 hygromycin susceptible plants, 14 plants with leaves available for in vitro feeding assay were subjected to the feeding of rice striped steam borers [Chilo supperssalis (Walker)] and all showed high resistance. The above results showed that spraying of 100 mg/L hygromycin solution at heading stage would lead to visually apparent toxic symptoms in susceptibility rice plants and hence

Application of gamma-ray irradiation technique to select, create and develop super rice with high quality to substitute the imported hybrid rice

International Nuclear Information System (INIS)

Tran Duy Quy; Tran Duy Vuong; Tran Duy Duong; Bui Huy Thuc

2015-01-01

Three varieties NPT3, BQ and TQ14 were selected by irradiation ray source Gamma Co-60 with dry seed, 13% grain moisture and created at 25-30 krad. NPT3 is super rice varieties with characteristics such as: extremely short growing period (105-110 day crop; 130- 135 days in the spring, the average yield of 9-10 tones/ha), quality, stem, leaf stand, suitable for intensive capability, able to resist pests and unfavorable conditions especially the elements of productivity (amylase from 15-16%) and mass produced including hybrid rice as Nhi Uu 868, Thien Nguyen Uu 9, HYT100, etc. BQ rice varieties were high quality, average productivity gain of 7.5- 8.0 ton/ha, equivalent to hybrid rice, short growth period (105-110 days in summer season; 120- 130 days in spring season), and quality rice: content 18-20% amylose, rice delicious, supple as BC15. TQ14 varieties was planted in 2 seasons/ year, with agricultural and biological characteristics as Khang-Dan18 mutant with wide adaptation, high yield potential, the average gain from 5.9 to 6.2 tones/ha, short growth period (105-110 days in summer season, 130-135 days in spring season), insect resistance, quality of rice suitable for manufacturing technology like noodles, instant noodles, rice noodles, Ethanol. (author)

Structure of fructo-oligosaccharides from leaves and stem of Agave tequilana Weber, var. azul.

Science.gov (United States)

Praznik, Werner; Löppert, Renate; Cruz Rubio, Josè M; Zangger, Klaus; Huber, Anton

2013-11-15

Fructo-oligosaccharides (FOSs) of a six year old agave plant variety, Agave tequilana, were isolated and fractionated by 2D preparative chromatography (SEC and rpHPLC). Structural analyses of different FOS-fractions were performed by reductive methylation analysis connected to GC/FID identification and NMR-analysis. FOSs from leaves (d.p. 3-8) contain single α-d-Glcp residues as well in terminal as internal position, however (2→1)-linked β-d-Fruf residues only. FOSs from stem, however, contain as well (2→1)- and (2→6)-linked β-d-Fruf residues with branched oligomeric repeating units. These characteristics indicate an enzymatically catalyzed metabolic regulation for the biosynthesis and transformation of fructans in A. tequilana which strongly depends on location and transport activities. Copyright © 2013 Elsevier Ltd. All rights reserved.

Does growth under elevated CO{sub 2} moderate photoacclimation in rice?

Energy Technology Data Exchange (ETDEWEB)

Hubbart, S.; Murchie, E.H.; Lake, J.A. [Univ. of Nottingham. School of Bioscience, Sutton Bonington (United Kingdom); Bird, S. [Univ. of York. Centre for Novel Agricultural Products, Dept. of Biology, York (United Kingdom)

2013-06-01

Acclimation of plant photosynthesis to light irradiance (photoacclimation) involves adjustments in levels of pigments and proteins and larger scale changes in leaf morphology. To investigate the impact of rising atmospheric CO{sub 2} on crop physiology, we hypothesize that elevated CO{sub 2} interacts with photoacclimation in rice (Oryza sativa). Rice was grown under high light (HL: 700 {mu}mol m{sup -2} s{sup -1}), low light (LL: 200 {mu}mol m{sup -2} s{sup -1}), ambient CO{sub 2} (400 {mu}l l{sup -1}) and elevated CO{sub 2} (1000 {mu}l l{sup -1}). Leaf six was measured throughout. Obscuring meristem tissue during development did not alter leaf thickness indicating that mature leaves are responsible for sensing light during photoacclimation. Elevated CO{sub 2} raised growth chamber photosynthesis and increased tiller formation at both light levels, while it increased leaf length under LL but not under HL. Elevated CO{sub 2} always resulted in increased leaf growth rate and tiller production. Changes in leaf thickness, leaf area, Rubisco content, stem and leaf starch, sucrose and fructose content were all dominated by irradiance and unaffected by CO{sub 2}. However, stomata responded differently; they were significantly smaller in LL grown plants compared to HL but this effect was significantly suppressed under elevated CO{sub 2}. Stomatal density was lower under LL, but this required elevated CO{sub 2} and the magnitude was adaxial or abaxial surface-dependent. We conclude that photoacclimation in rice involves a systemic signal. Furthermore, extra carbohydrate produced under elevated CO{sub 2} is utilized in enhancing leaf and tiller growth and does not enhance or inhibit any feature of photoacclimation with the exception of stomatal morphology. (Author)

Proteomic Analysis Reveals Coordinated Regulation of Anthocyanin Biosynthesis through Signal Transduction and Sugar Metabolism in Black Rice Leaf.

Science.gov (United States)

Chen, Linghua; Huang, Yining; Xu, Ming; Cheng, Zuxin; Zheng, Jingui

2017-12-15

Black rice ( Oryza sativa L.) is considered to be a healthy food due to its high content of anthocyanins in the pericarp. The synthetic pathway of anthocyanins in black rice grains has been identified, however, the proteomic profile of leaves during grain development is still unclear. Here, isobaric Tags Relative and Absolute Quantification (iTRAQ) MS/MS was carried out to identify statistically significant changes of leaf proteome in the black rice during grain development. Throughout three sequential developmental stages, a total of 3562 proteins were detected and 24 functional proteins were differentially expressed 3-10 days after flowering (DAF). The detected proteins are known to be involved in various biological processes and most of these proteins were related to gene expression regulatory (33.3%), signal transduction (16.7%) and developmental regulation and hormone-like proteins (12.5%). The coordinated changes were consistent with changes in regulatory proteins playing a leading role in leaves during black rice grain development. This indicated that signal transduction between leaves and grains may have an important role in anthocyanin biosynthesis and accumulation during grain development of black rice. In addition, four identified up-regulated proteins associated with starch metabolism suggested that the remobilization of nutrients for starch synthesis plays a potential role in anthocyanin biosynthesis of grain. The mRNA transcription for eight selected proteins was validated with quantitative real-time PCR. Our results explored the proteomics of the coordination between leaf and grain in anthocyanins biosynthesis of grain, which might be regulated by signal transduction and sugar metabolism in black rice leaf.

Proteomic Analysis Reveals Coordinated Regulation of Anthocyanin Biosynthesis through Signal Transduction and Sugar Metabolism in Black Rice Leaf

Directory of Open Access Journals (Sweden)

Linghua Chen

2017-12-01

Full Text Available Black rice (Oryza sativa L. is considered to be a healthy food due to its high content of anthocyanins in the pericarp. The synthetic pathway of anthocyanins in black rice grains has been identified, however, the proteomic profile of leaves during grain development is still unclear. Here, isobaric Tags Relative and Absolute Quantification (iTRAQ MS/MS was carried out to identify statistically significant changes of leaf proteome in the black rice during grain development. Throughout three sequential developmental stages, a total of 3562 proteins were detected and 24 functional proteins were differentially expressed 3–10 days after flowering (DAF. The detected proteins are known to be involved in various biological processes and most of these proteins were related to gene expression regulatory (33.3%, signal transduction (16.7% and developmental regulation and hormone-like proteins (12.5%. The coordinated changes were consistent with changes in regulatory proteins playing a leading role in leaves during black rice grain development. This indicated that signal transduction between leaves and grains may have an important role in anthocyanin biosynthesis and accumulation during grain development of black rice. In addition, four identified up-regulated proteins associated with starch metabolism suggested that the remobilization of nutrients for starch synthesis plays a potential role in anthocyanin biosynthesis of grain. The mRNA transcription for eight selected proteins was validated with quantitative real-time PCR. Our results explored the proteomics of the coordination between leaf and grain in anthocyanins biosynthesis of grain, which might be regulated by signal transduction and sugar metabolism in black rice leaf.

Excessive sulfur supply reduces cadmium accumulation in brown rice (Oryza sativa L.).

Science.gov (United States)

Fan, Jian-Ling; Hu, Zheng-Yi; Ziadi, Noura; Xia, Xu; Wu, Cong-Yang-Hui

2010-02-01

Human activities have resulted in cadmium (Cd) and sulfur (S) accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of excessive S supply on iron plaque formation and Cd accumulation in rice plants, using two Cd levels (0, 1.5 mg kg(-1)) combined with three S concentrations (0, 60, 120 mg kg(-1)). The results showed that excessive S supply significantly decreased Cd accumulation in brown rice due to the decrease of Cd availability and the increase of glutathione in rice leaves. But excessive S supply obviously increased Cd accumulation in roots due to the decrease of iron plaque formation on the root surface of rice. Therefore, excessive S supply may result in loss of rice yield, but it could effectively reduce Cd accumulation in brown rice exposed to Cd contaminated soils. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Residual, direct and cumulative effect of zinc application on wheat and rice yield under rice-wheat syst

Directory of Open Access Journals (Sweden)

R. Khan

2009-05-01

Full Text Available Zinc (Zn deficiency is prevalent particularly on calcareous soils of arid and semiarid region. A field experiment was conducted to investigate the direct, residual and cumulative effect of zinc on the yield of wheat and rice in permanent layout for two consecutive years, 2004-05 and 2005-06 at Arid Zone Research Institute D.I. Khan. Soil under study was deficient in Zn (0.8 mg kg-1. Effect of Zn on yield, Zn concentrations in leaf and soils were assessed using wheat variety Naseer-2000 and rice variety IRRI-6. Three rates of Zn, ranging from 0 to 10 kg ha-1 in soil, were applied as zinc sulphate (ZnSO4. 7H2O along with basal dose fertilization of nitrogen, phosphorus and potassium. Mature leaf and soil samples were collected at panicle initiation stage. The results showed that grain yield of wheat and rice was significantly increased by the direct application of 5 and 10 kg Zn ha-1. Highest grain yield of wheat (5467 kg ha-1 was recorded with the direct application of 10 kg Zn ha-1 while 4994 kg ha-1 was recorded with the cumulative application of 10 kg Zn ha-1 but the yield increase due to residual effect of Zn was statistically lower than the cumulative effect of Zn. Maximum paddy yield was recorded with the cumulative application ofZn followed by residual and direct applied 10 and 5 kg Zn kg ha-1, respectively. Zn concentration in soils ranged from 0.3 to 1.5 mg kg-1 in wheat and 0.24 to 2.40 mg kg-1 in rice, while in leaves it ranged from 18-48 mg kg-1 in wheat and 15-52 mg kg-1 in rice. The concentration of Zn in soil and leaves increased due to the treatments in the order; cumulative > residual > direct effect > control (without Zn. The yield attributes like 1000- grain weight, number of spikes, spike length and plant height were increased by the residual, direct and cumulative effect of Zn levels; however, the magnitude of increase was higher in cumulative effect than residual and direct effect of Zn, respectively. Under Zn-deficient soil

Metabolite modifications in Solanum lycopersicum roots and leaves ...

African Journals Online (AJOL)

During the treatment, Cd accumulated significantly in the roots compared to stems and leaves. Plant growth (root, stem and leaf) decreased when Cd concentration increased. The analysis of 1H-NMR spectra of polar extracts showed clear differences between metabolites amounts (soluble sugars, organic and amino acids) ...

Efficacy of ferterra 0.4% GR (chlorantraniliprole) against stem borers and leaffolder insect-pests of basmati rice.

Science.gov (United States)

Sarao, P S; Kaur, H

2014-09-01

Field experiments were conducted during three kharif seasons from 2009 to 2011 at Sudhar village, Ludhiana and Rice Research Area of Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana. Four doses of Ferterra 0.4% GR (chlorantraniliprole) a new chemistry @ 20, 30, 40 and 50 g a.i. ha(-1) and standard check Cartap hydrochloride 4 G @ 1000 g a.i. ha(-1) was tested against stem borers and leaffolder infesting basmati rice. Over the years, dead heart in all the Ferterra doses and standard check (1.01-1.80%) were at par70 DAT, whereas, at 80 DAT doses @ 40, 50 and standard check were at par (1.04-1.13%) but significantly better than lower doses and untreated control. Similarly, over the years, Ferterra doses @ 40 and 50 g a.i. ha(-1) was significantly better than control in reducing white ear incidence, whereas, at 30 g a.i. ha(-1) and standard check intermediately reduced the white ears incidence. Leaffolder infestation at all the Ferterra doses were at par with standard check 70 DAT (2.69-3.87%), whereas, 80 DAT, Ferterra doses @ 30, 40, 50 and standard check were at par (2.95-3.49%) but significantly better than lower dose and untreated control. Over the years the cost : benefit ratio was maximum (1 : 23.67) in the Ferterra @40 g a.i. ha(-1) dose followed by 50 g a.i. ha(-1) dose.

Gene expression analysis in rice plants after external radiation exposure in Iitate village

Energy Technology Data Exchange (ETDEWEB)

Hayashi, G.; Fukumoto, M. [Institute of Development, Aging and Cancer, Tohoku University (Japan); Imanaka, T. [Research Reactor Institute, Kyoto University (Japan); Shibato, J. [Department of Anatomy I, School of Medicine, Showa University (Japan); Kubo, A. [Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies (Japan); Kikuchi, S. [Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences (Japan); Rakwal, R. [Organization for Educational Initiatives, University of Tsukuba (Japan)

2014-07-01

Rice plants exposed to radiation respond to the stress by activating self-defense mechanisms. A well-established molecular approach to measure stress is by cataloging global gene expression profiles. Here, we examined the effect of radiation exposure in a cereal crop model plant - rice (Oryza sativa L.) cultivar Nipponbare - in the village of Iitate of Fukushima prefecture. Iitate village is a highly radio-contaminated site due to the Fukushima Daiichi nuclear power plant accident following the Great East Japan Earthquake. The experimental approach comprised of five steps. First, healthy rice seedlings were grown in the greenhouse facility at National Institute for Environmental Sciences. Post-germination at 30 deg. C similarly germinated seeds were placed in neat rows in seedling pots having commercial soil (JA Zen-Noh, Japan; http//www.zennoh.or.jp/) with recommended NPK (nitrogen, phosphorus, and potash) doses at a controlled (25 deg. C, 70% relative humidity and natural light condition) greenhouse. Second, the seedlings were transported from a controlled greenhouse in Tsukuba to Iitate Farm (ITF) and placed, with no direct contact with soil, in a low-level gamma field where the rate of Cs-137 was 700 kBq/m{sup 2}. Third, exposure periods were set at 6, 12, 24, 48, and 72 h after arrival at ITF, and rice leaves at the 3. position (from the base) from 6 to 10 seedlings were sampled in dry ice. As control, rice leaves were sampled at the start in Tsukuba and immediately at arrival upon ITF; to know the radiation levels during growth and transport of the rice to ITF, accumulated radiation dose was calculated using a MYDOSE mini electronic pocket dosimeter (model PDM-222-52, ALOKA, Japan). A sample set was also taken at 72 h from healthy rice seedlings in the greenhouse at Tsukuba. All samples were stored at -80 deg. C. Accumulated total dose for exposed rice seedlings at 72 h was 200 mSv. Fourth, gene expression analysis was initiated by grinding the leaves to a

Monitoring leaf photosynthesis with canopy spectral reflectance in rice

International Nuclear Information System (INIS)

Tian, Y.; Zhu, Y.; Cao, W.

2005-01-01

We determined the quantitative relationships between leaf photosynthetic characteristics (LPC) and canopy spectral reflectance under different water supply and nitrogen application rates in rice plants. The responses of reflectance at red radiation (680 nm) to different water contents and N rates were parallel to those of leaf net photosynthetic rate (PN). The relationships of reflectance at 680 nm and ratio index of R(810,680) (near infrared/red) to PN of different leaf positions and layers indicated that the top two full leaves were the best positions for quantitative monitoring of PN with remote sensing technique, and the index R(810,680) was the best ratio index for evaluating LPC. Testing of the models with independent data sets indicated that R(810,680) could well estimate PN of the top two leaves and canopy leaf photosynthetic potential. Hence R(810,680) can be used to monitor LPC in rice under diverse growing conditions

Transcriptome Analysis of Salt Stress Responsiveness in the Seedlings of Dongxiang Wild Rice (Oryza rufipogon Griff.).

Science.gov (United States)

Zhou, Yi; Yang, Ping; Cui, Fenglei; Zhang, Fantao; Luo, Xiangdong; Xie, Jiankun

2016-01-01

Dongxiang wild rice (Oryza rufipogon Griff.) is the progenitor of cultivated rice (Oryza sativa L.), and is well known for its superior level of tolerance against cold, drought and diseases. To date, however, little is known about the salt-tolerant character of Dongxiang wild rice. To elucidate the molecular genetic mechanisms of salt-stress tolerance in Dongxiang wild rice, the Illumina HiSeq 2000 platform was used to analyze the transcriptome profiles of the leaves and roots at the seedling stage under salt stress compared with those under normal conditions. The analysis results for the sequencing data showed that 6,867 transcripts were differentially expressed in the leaves (2,216 up-regulated and 4,651 down-regulated) and 4,988 transcripts in the roots (3,105 up-regulated and 1,883 down-regulated). Among these differentially expressed genes, the detection of many transcription factor genes demonstrated that multiple regulatory pathways were involved in salt stress tolerance. In addition, the differentially expressed genes were compared with the previous RNA-Seq analysis of salt-stress responses in cultivated rice Nipponbare, indicating the possible specific molecular mechanisms of salt-stress responses for Dongxiang wild rice. A large number of the salt-inducible genes identified in this study were co-localized onto fine-mapped salt-tolerance-related quantitative trait loci, providing candidates for gene cloning and elucidation of molecular mechanisms responsible for salt-stress tolerance in rice.

Differences in phytoalexin response among rice cultivars of different resistance to blast

International Nuclear Information System (INIS)

Dillon, V.M.; Overton, J.; Grayer, R.J.; Harborne, J.B.

1997-01-01

he production of both flavonoid and diterpenoid phytoalexins after induction by UV irradiation was studied in five rice genotypes of different susceptibility to the rice blast fungus Pyricularia oryzae. Consistent qualitative and quatitative differences were found between the rice cultivars in the phytoalexins produced, and there was a strong correlation between the accumulation of the phytoalexins, sakuranetin, momilactone A and oryzalexin S, and rice resistance to blast. Production of phytoalexins was also investigated in rice genotype Tetep after inoculation with an incompatible race of P. oryzae. Similar levels of sakuranetin and oryzalexin E were formed 3 days after both inoculation and UV irradiation of the leaves, but there were different levels of momilactone A and the other oryzalexins. Although a given rice genotype may respond quite differently in its production of phytoalexins depending on whether it has been irradiated or inoculated with a fungus, and in the latter case on whether a compatible race of the pathogen has been used, the present results indicate that genetic differences in phytoalexin response between rice cultivars are likely to play an important role among the many factors that determine differences in blast resistance between different rice genotypes. (author)

Classification of Malaysia aromatic rice using multivariate statistical analysis

Energy Technology Data Exchange (ETDEWEB)

Abdullah, A. H.; Adom, A. H.; Shakaff, A. Y. Md; Masnan, M. J.; Zakaria, A.; Rahim, N. A. [School of Mechatronic Engineering, Universiti Malaysia Perlis, Kampus Pauh Putra, 02600 Arau, Perlis (Malaysia); Omar, O. [Malaysian Agriculture Research and Development Institute (MARDI), Persiaran MARDI-UPM, 43400 Serdang, Selangor (Malaysia)

2015-05-15

Aromatic rice (Oryza sativa L.) is considered as the best quality premium rice. The varieties are preferred by consumers because of its preference criteria such as shape, colour, distinctive aroma and flavour. The price of aromatic rice is higher than ordinary rice due to its special needed growth condition for instance specific climate and soil. Presently, the aromatic rice quality is identified by using its key elements and isotopic variables. The rice can also be classified via Gas Chromatography Mass Spectrometry (GC-MS) or human sensory panels. However, the uses of human sensory panels have significant drawbacks such as lengthy training time, and prone to fatigue as the number of sample increased and inconsistent. The GC–MS analysis techniques on the other hand, require detailed procedures, lengthy analysis and quite costly. This paper presents the application of in-house developed Electronic Nose (e-nose) to classify new aromatic rice varieties. The e-nose is used to classify the variety of aromatic rice based on the samples odour. The samples were taken from the variety of rice. The instrument utilizes multivariate statistical data analysis, including Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and K-Nearest Neighbours (KNN) to classify the unknown rice samples. The Leave-One-Out (LOO) validation approach is applied to evaluate the ability of KNN to perform recognition and classification of the unspecified samples. The visual observation of the PCA and LDA plots of the rice proves that the instrument was able to separate the samples into different clusters accordingly. The results of LDA and KNN with low misclassification error support the above findings and we may conclude that the e-nose is successfully applied to the classification of the aromatic rice varieties.

Classification of Malaysia aromatic rice using multivariate statistical analysis

Science.gov (United States)

Abdullah, A. H.; Adom, A. H.; Shakaff, A. Y. Md; Masnan, M. J.; Zakaria, A.; Rahim, N. A.; Omar, O.

2015-05-01

Aromatic rice (Oryza sativa L.) is considered as the best quality premium rice. The varieties are preferred by consumers because of its preference criteria such as shape, colour, distinctive aroma and flavour. The price of aromatic rice is higher than ordinary rice due to its special needed growth condition for instance specific climate and soil. Presently, the aromatic rice quality is identified by using its key elements and isotopic variables. The rice can also be classified via Gas Chromatography Mass Spectrometry (GC-MS) or human sensory panels. However, the uses of human sensory panels have significant drawbacks such as lengthy training time, and prone to fatigue as the number of sample increased and inconsistent. The GC-MS analysis techniques on the other hand, require detailed procedures, lengthy analysis and quite costly. This paper presents the application of in-house developed Electronic Nose (e-nose) to classify new aromatic rice varieties. The e-nose is used to classify the variety of aromatic rice based on the samples odour. The samples were taken from the variety of rice. The instrument utilizes multivariate statistical data analysis, including Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and K-Nearest Neighbours (KNN) to classify the unknown rice samples. The Leave-One-Out (LOO) validation approach is applied to evaluate the ability of KNN to perform recognition and classification of the unspecified samples. The visual observation of the PCA and LDA plots of the rice proves that the instrument was able to separate the samples into different clusters accordingly. The results of LDA and KNN with low misclassification error support the above findings and we may conclude that the e-nose is successfully applied to the classification of the aromatic rice varieties.

Classification of Malaysia aromatic rice using multivariate statistical analysis

International Nuclear Information System (INIS)

Abdullah, A. H.; Adom, A. H.; Shakaff, A. Y. Md; Masnan, M. J.; Zakaria, A.; Rahim, N. A.; Omar, O.

2015-01-01

Aromatic rice (Oryza sativa L.) is considered as the best quality premium rice. The varieties are preferred by consumers because of its preference criteria such as shape, colour, distinctive aroma and flavour. The price of aromatic rice is higher than ordinary rice due to its special needed growth condition for instance specific climate and soil. Presently, the aromatic rice quality is identified by using its key elements and isotopic variables. The rice can also be classified via Gas Chromatography Mass Spectrometry (GC-MS) or human sensory panels. However, the uses of human sensory panels have significant drawbacks such as lengthy training time, and prone to fatigue as the number of sample increased and inconsistent. The GC–MS analysis techniques on the other hand, require detailed procedures, lengthy analysis and quite costly. This paper presents the application of in-house developed Electronic Nose (e-nose) to classify new aromatic rice varieties. The e-nose is used to classify the variety of aromatic rice based on the samples odour. The samples were taken from the variety of rice. The instrument utilizes multivariate statistical data analysis, including Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and K-Nearest Neighbours (KNN) to classify the unknown rice samples. The Leave-One-Out (LOO) validation approach is applied to evaluate the ability of KNN to perform recognition and classification of the unspecified samples. The visual observation of the PCA and LDA plots of the rice proves that the instrument was able to separate the samples into different clusters accordingly. The results of LDA and KNN with low misclassification error support the above findings and we may conclude that the e-nose is successfully applied to the classification of the aromatic rice varieties

Phytochemical and pharmacological variability in Golden Thistle functional parts: comparative study of roots, stems, leaves and flowers.

Science.gov (United States)

Marmouzi, Ilias; El Karbane, Miloud; El Hamdani, Maha; Kharbach, Mourad; Naceiri Mrabti, Hanae; Alami, Rachid; Dahraoui, Souhail; El Jemli, Meryem; Ouzzif, Zhor; Cherrah, Yahia; Derraji, Soufiane; Faouzi, My El Abbes

2017-11-01

Scolymus hispanicus or the Golden Thistle, locally known as 'Guernina' or 'Taghediwt', is one of the most appreciated wild vegetables in Morocco. This study aims to characterise the functional chemical and pharmacological variability of Scolymus hispanicus parts (roots, stems, leaves and flowers). The chemical analysis revealed higher content of α-tocopherol in the flowers (2.79 ± 0.07 mg/100 g) and lead to the identification of 3 flavonoids and 13 phenolic acids, with high content of gallic acid in leaves (187.01 ± 10.19 mg/kg); chlorogenic (936.18 ± 92.66 mg/kg) and caffeic (4400.14 ± 191.43 mg/kg) acids in flowers, roots were much more higher in sinapic acid (0.25 ± 0.03 mg/kg) compared to the other parts. Moreover, Scolymus hispanicus ethanolic extracts exhibited interesting antioxidant and antimicrobial properties, promising anti-amylase and anti-glucosidase activities and relevant diuretic effect that confirms its traditional uses.

Grain, milling, and head rice yields as affected by nitrogen rate and bio-fertilizer application

Directory of Open Access Journals (Sweden)

Saeed FIROUZI

2015-11-01

Full Text Available To evaluate the effects of nitrogen rate and bio-fertilizer application on grain, milling, and head rice yields, a field experiment was conducted at Rice Research Station of Tonekabon, Iran, in 2013. The experimental design was a factorial treatment arrangement in a randomized complete block with three replicates. Factors were three N rates (0, 75, and 150 kg ha-1 and two bio-fertilizer applications (inoculation and uninoculation with Nitroxin, a liquid bio-fertilizer containing Azospirillum spp. and Azotobacter spp. bacteria. Analysis of variance showed that rice grain yield, panicle number per m2, grain number per panicle, flag leaves area, biological yield, grains N concentration and uptake, grain protein concentration, and head rice yield were significantly affected by N rate, while bio-fertilizer application had significant effect on rice grain yield, grain number per panicle, flag leaves area, biological yield, harvest index, grains N concentration and uptake, and grain protein concentration. Results showed that regardless of bio-fertilizer application, rice grain and biological yields were significantly increased as N application rate increased from 0 to 75 kg ha-1, but did not significantly increase at the higher N rate (150 kg ha-1. Grain yield was significantly increased following bio-fertilizer application when averaged across N rates. Grains N concentration and uptake were significantly increased as N rate increased up to 75 kg ha-1, but further increases in N rate had no significant effect on these traits. Bio-fertilizer application increased significantly grains N concentration and uptake, when averaged across N rates. Regardless of bio-fertilizer application, head rice yield was significantly increased from 56 % to 60 % when N rate increased from 0 to 150 kg ha-1. Therefore, this experiment illustrated that rice grain and head yields increased with increasing N rate, while bio-fertilizer application increased only rice grain

Phytochemical screening and antimicrobial activity of roots, stem ...

African Journals Online (AJOL)

The roots, stem-bark and leaves of Grewia mollis which is used as herbal remedies for the cure of diarrhea and dysentery by natives in northern part of Nigeria were studied. The ethanol and water extracts of roots, stem-bark and leaves of the plant were subjected to phytochemical screening and antimicrobial activity against ...

Transfer of technetium from soil to paddy and upland rice

International Nuclear Information System (INIS)

Yanagisawa, Kei; Muramatsu, Yasuyuki

1995-01-01

Soil-plant transfer factors (concentration ratio between the plant and soil) of technetium in paddy and upland rice plants were obtained from laboratory experiments. The transfer factor is one of the most important parameters for environmental radiation dose assessment. Technetium tracer ( 95m TcO 4 - ) was added to the soil prior to rice cultivation. The transfer factor of technetium for the hulled grains (brown rice) of paddy rice (≤0.0002) was much lower than for that of upland rice (0.021). The transfer factors for both types of hulled grains were much lower than in the leaves. The technetium decontamination rate from hulled grains by polishing was 34%, the percentage of the weight decrease being 12%. The concentration of technetium in the soil solution collected from the paddy rice soil (flooded conditions) decreased rapidly with time due to its adsorption on the soil. In the upland rice soil (non-flooded) solution, the decrease in the technetium concentration was fairly slow. The low transfer factors for the paddy rice plants could be explained by the immobilization of technetium in the flooded soil. The oxidation-reduction potentials (Eh) in the flooded soil decreased rapidly with time. We conclude that technetium tracer added as TcO 4 - to flooded soil is readily transformed to an insoluble form (e.g.TcO 2 ) under the reducing conditions provided by flooding. (author)

Enhanced Sucrose Loading Improves Rice Yield by Increasing Grain Size.

Science.gov (United States)

Wang, Liang; Lu, Qingtao; Wen, Xiaogang; Lu, Congming

2015-12-01

Yield in cereals is a function of grain number and size. Sucrose (Suc), the main carbohydrate product of photosynthesis in higher plants, is transported long distances from source leaves to sink organs such as seeds and roots. Here, we report that transgenic rice plants (Oryza sativa) expressing the Arabidopsis (Arabidopsis thaliana) phloem-specific Suc transporter (AtSUC2), which loads Suc into the phloem under control of the phloem protein2 promoter (pPP2), showed an increase in grain yield of up to 16% relative to wild-type plants in field trials. Compared with wild-type plants, pPP2::AtSUC2 plants had larger spikelet hulls and larger and heavier grains. Grain filling was accelerated in the transgenic plants, and more photoassimilate was transported from the leaves to the grain. In addition, microarray analyses revealed that carbohydrate, amino acid, and lipid metabolism was enhanced in the leaves and grain of pPP2::AtSUC2 plants. Thus, enhancing Suc loading represents a promising strategy to improve rice yield to feed the global population. © 2015 American Society of Plant Biologists. All Rights Reserved.

Effect of cultural practices on the incidence and carry over of insect pests in rice-wheat system

International Nuclear Information System (INIS)

Ramzan, M.; Akhtar, M.; Hussain, S.

2008-01-01

Changes in cultural practices in rice-wheat system like mechanical transplanted rice, broadcasting (parachute method) of rice seedlings, direct seeding of rice, bed planting of rice and wheat and zero-till wheat sowing may affect population of insect pests and their natural enemies. The population of insect pests and their damage intensity on rice and wheat crops were determined for resource conservation technologies in rice-wheat system. Unploughed fallow fields and those planted with berseem are the major over-wintering sites of rice stem borers (RSB). Growing of wheat after rice, either by conventional or zero-tillage minimizes RSB problem. The effect of technological shifts in rice-wheat systems was discussed on leaffolder (LF) and white backed planthopper (WBPH) populations. Conservation tillage might take on preventive management as the diversity and population size of many beneficial organisms, especially soil-inhabiting predators, can be increased. (author)

Antiadipogenic Activity of γ-Oryzanol and Its Stability in Pigmented Rice.

Science.gov (United States)

Minatel, Igor Otavio; Lee, Yoon-Mi; Yoon, Haelim; Yoon, Young; Han, Sang-Ik; Correa, Camila Renata; Fecchio, Denise; Yeum, Kyung-Jin

2016-07-01

γ-Oryzanol, a prevalent compound in pigmented rice varieties, has been reported to ameliorate obesity-associated metabolic disorders. Antiadipogenic activities of γ-oryzanol were determined in human adipose-derived mesenchymal stem cells and mouse-derived 3T3-L1 cells. γ-Oryzanol significantly decreased lipid accumulation and reduced glycerol-3-phosphate dehydrogenase activities in both adipocytes. In addition, γ-oryzanol in four pigmented rice varieties (black with giant embryo, brown, sugary brown, and red) was stable when stored at 4°C and also at room temperature for 22 weeks, whereas other bioactives such as lutein and β-carotene were stable only at -80°C. Furthermore, the yield of γ-oryzanol from these rice varieties was significantly increased through steaming and roasting processes. Therefore, γ-oryzanol exerts antiadipogenic activity by suppressing adipocyte differentiations and is stable in pigmented rice for an extended period of time during storage and after cooking. Thus, the intake of pigmented rice may be a useful strategy for preventing obesity.

An Inclusive Investigation on Conceivable Performance of Rice Straw Incinerated Electricity Generation

Science.gov (United States)

Bhattacharjee, Subhadeep; Mohanta, Subhajit

2018-03-01

Biomass energy is one of the potential renewable energy sources which occupy 77% of the available natural resources of the world. In India, agro residues constitute a major part of the total annual production of the biomass resource. Rice is the major crop in India that leaves substantial quantity of straw in the field. 34% of rice straw residue produced in the country is surplus and is either left in the field as uncollected or to a large extent open-field burnt. Thus, the unutilized rice straw is found promising for heat and power generation either through incineration (direct combustion) or thermo chemical conversion. This present work envisages the comprehensive performative evaluation of a rice straw supported biomass incineration power plant mainly through plant performance characterization, plant economics, and co-firing issues with emission analysis.

In vitro sterilization technique on embryo of black Toraja rice

Science.gov (United States)

Haring, F.; Riadi, M.; Rafiuddin; Sjahril, R.; Muchlis, A. R.

2018-05-01

Toraja black rice has a high anthocyanin content, a water-soluble pigments, with antioxidant activity. Toraja black rice has a variety of seeds colour in one panicles such as full black (the outside and inside the rice), medium black (the outside and slightly inside rice) and a little black (only the outside of rice). Embryo culture in vitro is one way to grow plants in sterile conditions. The presence of contamination and the death of the embryo require in vitro embryo culture. The sterilization technique is a very important first step to eliminate contamination and the death of embryos. This research aims to determine the right material composition for sterilization of black rice’s embryo. The experiment was done by growing black rice on half strength MS media with the treatment of three method of sterilization, i.e.: S1 (70% alcohol for 5 minutes, 3% and 2% Chlorox each for 10 minutes,), S2 (70% alcohol for 3 minutes, 2% Clorox for 10 minutes) and S3 (70% alcohol for 3 minutes and 1% Clorox for 15 minutes). The materials used are rice seedlings that have been cut in two and opened the pericarp of paddy grain, leaving a piece of rice that has a complete embryo. The best sterilization for Toraja black rice embryo culture was using the S3 composition. Best germination was seen on the seeds with full and medium black color.

What’s So Special about STEM? A Comparison of Women’s Retention in STEM and Professional Occupations

OpenAIRE

Glass, Jennifer L.; Sassler, Sharon; Levitte, Yael; Michelmore, Katherine M.

2013-01-01

We follow female college graduates in the National Longitudinal Survey of Youth 1979 and compare the trajectories of women in science, technology, engineering, and mathematics (STEM)-related occupations to other professional occupations. Results show that women in STEM occupations are significantly more likely to leave their occupational field than professional women, especially early in their career, while few women in either group leave jobs to exit the labor force. Family factors cannot ac...

Stem photosynthesis in a desert ephemeral, Eriogonum inflatum : Characterization of leaf and stem CO2 fixation and H2O vapor exchange under controlled conditions.

Science.gov (United States)

Osmond, C B; Smith, S D; Gui-Ying, B; Sharkey, T D

1987-07-01

The gas exchange characteristics of photosynthetic tissues of leaves and stems of Eriogonum inflatum are described. Inflated stems were found to contain extraordinarily high internal CO 2 concentrations (to 14000 μbar), but fixation of this internal CO 2 was 6-10 times slower than fixation of atmospheric CO 2 by these stems. Although the pool of CO 2 is a trivial source of CO 2 for stem photosynthesis, it may result in higher water-use efficiency of stem tissues. Leaf and stem photosynthetic activities were compared by means of CO 2 fixation in CO 2 response curves, light and temperature response curves in IRGA systems, and by means of O 2 exchange at CO 2 saturation in a leaf disc O 2 electrode system. On an area basis leaves contain about twice the chlorophyll and nitrogen as stems, and are capable of up to 4-times the absolute CO 2 and O 2 exchange rates. However, the stem shape is such that lighting of the shaded side leads to a substantial increase in overall stem photosynthesis on a projected area basis, to about half the leaf rate in air. Stem conductance is lower than leaf conductance under most conditions and is less sensitive to high temperature or high VPD. Under most conditions, the ratio C i /C a is lower in stems than in leaves and stems show greater water-use efficiency (higher ratio assimilation/transpiration) as a function of VPD. This potential advantage of stem photosynthesis in a water limited environment may be offset by the higher VPD conditions in the hotter, drier part of the year when stems are active after leaves have senesced. Stem and leaf photosynthesis were similarly affected by decreasing plant water potential.

Effects of slag-based silicon fertilizer on rice growth and brown-spot resistance.

Science.gov (United States)

Ning, Dongfeng; Song, Alin; Fan, Fenliang; Li, Zhaojun; Liang, Yongchao

2014-01-01

It is well documented that slag-based silicon fertilizers have beneficial effects on the growth and disease resistance of rice. However, their effects vary greatly with sources of slag and are closely related to availability of silicon (Si) in these materials. To date, few researches have been done to compare the differences in plant performance and disease resistance between different slag-based silicon fertilizers applied at the same rate of plant-available Si. In the present study both steel and iron slags were chosen to investigate their effects on rice growth and disease resistance under greenhouse conditions. Both scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the effects of slags on ultrastructural changes in leaves of rice naturally infected by Bipolaris oryaze, the causal agent of brown spot. The results showed that both slag-based Si fertilizers tested significantly increased rice growth and yield, but decreased brown spot incidence, with steel slag showing a stronger effect than iron slag. The results of SEM analysis showed that application of slags led to more pronounced cell silicification in rice leaves, more silica cells, and more pronounced and larger papilla as well. The results of TEM analysis showed that mesophyll cells of slag-untreated rice leaf were disorganized, with colonization of the fungus (Bipolaris oryzae), including chloroplast degradation and cell wall alterations. The application of slag maintained mesophyll cells relatively intact and increased the thickness of silicon layer. It can be concluded that applying slag-based fertilizer to Si-deficient paddy soil is necessary for improving both rice productivity and brown spot resistance. The immobile silicon deposited in host cell walls and papillae sites is the first physical barrier for fungal penetration, while the soluble Si in the cytoplasm enhances physiological or induced resistance to fungal colonization.

Metabolic fate of 14-C-fenitrothion in a rice field model ecosystem

International Nuclear Information System (INIS)

Nashriyah binti Mat; Nambu, K.; Miyashita, T.; Sakata, S.; Ohshima, M.

1991-01-01

Pesticide fenitrothion (Sumithion sup R)is widely used to control rice stem borer and other pests. Its metabolic fate and degradation was studied using the sup 14 C-ring labelled fenitrothion in a model ecosystem consisting of Takarazuka paddy field soil, rice plant (Oryza sativa var. nihonbare), carp fish (Cyprinus carpio L.) and dechlorinated water. Radioactive fenitrothion was applied at a normal rate as used by Japanese farmers and samples of rice plant, fish soil and water were analysed after ten days of application. Fenitrothion was readily metabolized in rice plant and fish and also readily degraded to a number of metabolites in water and flooded soil. Most of the radioactivity applied was found in the soil component of the ecosystem. A trace amount of fenitrooxon, the activated metabolite of fenitrothion was detected only in soil and water. A possible metabolic pathway of fenitrothion in the rice model ecosystem was proposed

Evaluating Leaf and Canopy Reflectance of Stressed Rice Plants to Monitor Arsenic Contamination

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Varaprasad Bandaru

2016-06-01

Full Text Available Arsenic contamination is a serious problem in rice cultivated soils of many developing countries. Hence, it is critical to monitor and control arsenic uptake in rice plants to avoid adverse effects on human health. This study evaluated the feasibility of using reflectance spectroscopy to monitor arsenic in rice plants. Four arsenic levels were induced in hydroponically grown rice plants with application of 0, 5, 10 and 20 µmol·L−1 sodium arsenate. Reflectance spectra of upper fully expanded leaves were acquired over visible and infrared (NIR wavelengths. Additionally, canopy reflectance for the four arsenic levels was simulated using SAIL (Scattering by Arbitrarily Inclined Leaves model for various soil moisture conditions and leaf area indices (LAI. Further, sensitivity of various vegetative indices (VIs to arsenic levels was assessed. Results suggest that plants accumulate high arsenic amounts causing plant stress and changes in reflectance characteristics. All leaf spectra based VIs related strongly with arsenic with coefficient of determination (r2 greater than 0.6 while at canopy scale, background reflectance and LAI confounded with spectral signals of arsenic affecting the VIs’ performance. Among studied VIs, combined index, transformed chlorophyll absorption reflectance index (TCARI/optimized soil adjusted vegetation index (OSAVI exhibited higher sensitivity to arsenic levels and better resistance to soil backgrounds and LAI followed by red edge based VIs (modified chlorophyll absorption reflectance index (MCARI and TCARI suggesting that these VIs could prove to be valuable aids for monitoring arsenic in rice fields.

Temperature drives global patterns in forest biomass distribution in leaves, stems, and roots.

Science.gov (United States)

Reich, Peter B; Luo, Yunjian; Bradford, John B; Poorter, Hendrik; Perry, Charles H; Oleksyn, Jacek

2014-09-23

Whether the fraction of total forest biomass distributed in roots, stems, or leaves varies systematically across geographic gradients remains unknown despite its importance for understanding forest ecology and modeling global carbon cycles. It has been hypothesized that plants should maintain proportionally more biomass in the organ that acquires the most limiting resource. Accordingly, we hypothesize greater biomass distribution in roots and less in stems and foliage in increasingly arid climates and in colder environments at high latitudes. Such a strategy would increase uptake of soil water in dry conditions and of soil nutrients in cold soils, where they are at low supply and are less mobile. We use a large global biomass dataset (>6,200 forests from 61 countries, across a 40 °C gradient in mean annual temperature) to address these questions. Climate metrics involving temperature were better predictors of biomass partitioning than those involving moisture availability, because, surprisingly, fractional distribution of biomass to roots or foliage was unrelated to aridity. In contrast, in increasingly cold climates, the proportion of total forest biomass in roots was greater and in foliage was smaller for both angiosperm and gymnosperm forests. These findings support hypotheses about adaptive strategies of forest trees to temperature and provide biogeographically explicit relationships to improve ecosystem and earth system models. They also will allow, for the first time to our knowledge, representations of root carbon pools that consider biogeographic differences, which are useful for quantifying whole-ecosystem carbon stocks and cycles and for assessing the impact of climate change on forest carbon dynamics.

The effects of replacing Dichantium hay with banana (Musa paradisiaca) leaves and pseudo-stem on carcass traits of Ovin Martinik sheep.

Science.gov (United States)

Marie-Magdeleine, Carine; Liméa, Léticia; Etienne, Tatiana; Lallo, Cicero H O; Archimède, Harry; Alexandre, Gisele

2009-10-01

A study was done to evaluate banana (Musa paradisiaca) as a forage (leaves and pseudo-stems) for feeding Ovin Martinik lambs (OMK), with the aim to test its impact on carcass quality. Forty four intact OMK male were used after weaning with an initial mean live weight of 14.4 (+/- 3.3) kg, reared in individual pens. Animals were offered either Dichantium hay (control diet, Dh) or cut chopped leaves and pseudo-stems of banana (experimental diet, Blps). They were fed 200-250 g x d(-1) of commercial concentrate. Lambs were slaughtered according to 3 classes of slaughter weight (SW): SW20, SW23 and SW26. Growth and carcass performances of both groups were not significantly different, 77 vs. 81 g x d(-1) and 42% vs. 43% hot carcass yield, for Dh vs. Blps, respectively. There was a significant (P < 0.05) decrease (31.0 vs. 29.7%) for the dry matter content of the shoulder for lambs fed the banana diet. However, there was no effect observed for the other chemical component (CP, lipid and mineral 585, 317 and 95 g x kg(-1) DM, respectively). The shoulder (20% of the carcass whatever the SW) was precocious as demonstrated by the allometry coefficient relative to carcass weight (0.894) significantly (P < 0.01) less than 1. It was concluded that, the use of Blps had no significant effect on growth, carcass weights and yields of the OMK lambs, irrespective of the class of the slaughter weight. From these initial results, the use of banana foliages and pseudo-stems could be recommended as sources of forages.

A novel method for transmitting southern rice black-streaked dwarf virus to rice without insect vector.

Science.gov (United States)

Yu, Lu; Shi, Jing; Cao, Lianlian; Zhang, Guoping; Wang, Wenli; Hu, Deyu; Song, Baoan

2017-08-15

Southern rice black-streaked dwarf virus (SRBSDV) has spread from the south of China to the north of Vietnam in the past few years, and has severely influenced rice production. However, previous study of traditional SRBSDV transmission method by the natural virus vector, the white-backed planthopper (WBPH, Sogatella furcifera), in the laboratory, researchers are frequently confronted with lack of enough viral samples due to the limited life span of infected vectors and rice plants and low virus acquisition and inoculation efficiency by the vector. Meanwhile, traditional mechanical inoculation of virus only apply to dicotyledon because of the higher content of lignin in the leaves of the monocot. Therefore, establishing an efficient and persistent-transmitting model, with a shorter virus transmission time and a higher virus transmission efficiency, for screening novel anti-SRBSDV drugs is an urgent need. In this study, we firstly reported a novel method for transmitting SRBSDV in rice using the bud-cutting method. The transmission efficiency of SRBSDV in rice was investigated via the polymerase chain reaction (PCR) method and the replication of SRBSDV in rice was also investigated via the proteomics analysis. Rice infected with SRBSDV using the bud-cutting method exhibited similar symptoms to those infected by the WBPH, and the transmission efficiency (>80.00%), which was determined using the PCR method, and the virus transmission time (30 min) were superior to those achieved that transmitted by the WBPH. Proteomics analysis confirmed that SRBSDV P1, P2, P3, P4, P5-1, P5-2, P6, P8, P9-1, P9-2, and P10 proteins were present in infected rice seedlings infected via the bud-cutting method. The results showed that SRBSDV could be successfully transmitted via the bud-cutting method and plants infected SRBSDV exhibited the symptoms were similar to those transmitted by the WBPH. Therefore, the use of the bud-cutting method to generate a cheap, efficient, reliable supply of

Cytokinin delays dark-induced senescence in rice by maintaining the chlorophyll cycle and photosynthetic complexes.

Science.gov (United States)

Talla, Sai Krishna; Panigrahy, Madhusmita; Kappara, Saivishnupriya; Nirosha, P; Neelamraju, Sarla; Ramanan, Rajeshwari

2016-03-01

The phytohormone cytokinin (CK) is known to delay senescence in plants. We studied the effect of a CK analog, 6-benzyl adenine (BA), on rice leaves to understand the possible mechanism by which CK delays senescence in a drought- and heat-tolerant rice cultivar Nagina22 (N22) using dark-induced senescence (DIS) as a surrogate for natural senescence of leaves. Leaves of N22-H-dgl162, a stay-green mutant of N22, and BA-treated N22 showed retention of chlorophyll (Chl) pigments, maintenance of the Chl a/b ratio, and delay in reduction of both photochemical efficiency and rate of oxygen evolution during DIS. HPLC analysis showed accumulation of 7-hydroxymethyl chlorophyll (HmChl) during DIS, and the kinetics of its accumulation correlated with progression of senescence. Transcriptome analysis revealed that several plastid-localized genes, specifically those associated with photosystem II (PSII), showed higher transcript levels in BA-treated N22 and the stay-green mutant leaves compared with naturally senescing N22 leaves. Real-time PCR analyses showed that genes coding for enzymes associated with Chl a/b interconversion and proteins associated with light-harvesting complexes maintained higher transcript levels up to 72h of DIS following BA treatment. The pigment-protein complexes analyzed by green gel remained intact in both N22-H-dgl162 and BA-treated N22 leaves even after 96h of DIS. Thus, CK delays senescence by accumulation of HmChl and up-regulating genes in the Chl cycle, thereby maintaining the Chl a/b ratio. Also, CK treatment retains higher transcript levels of PSII-related genes, resulting in the stability of photosynthetic pigment complexes and functional stay-greenness in rice. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Studies on the antidiabetic effects of Mangifera indica stem-barks and leaves on nondiabetic, type 1 and type 2 diabetic model rats

Directory of Open Access Journals (Sweden)

Amrita Bhowmik

2009-06-01

Full Text Available Mangifera indica Linn, locally known as mango tree has been claimed to possess antidiabetic properties by many investigators. The present study was undertaken to screen the hypo- and antihyperglycemic activity of both ethanol and water extracts of leaves and stem-barks of M. indica in nondiabetic and diabetic model rats in different prandial states. The results showed that all of the extracts had significant antihyperglycemic effect in type 2 model rats when fed simultaneously with glucose load (p< 0.05-0.01; p< 0.005-0.001. Moreover, the ethanol extract of stem-barks showed significant antihyperglycemic effect when the extract was fed 30 min prior to the glucose load (p< 0.01. Investigations were carried out to evaluate the effect of M. indica on glucose absorption using a rat intestinal preparation in situ. The ethanol extracts of stem-barks reduced glucose absorption gradually during the whole perfusion period in type 2 rats.

Studies on the antidiabetic effects of Mangifera indica stem-barks and leaves on nondiabetic, type 1 and type 2 diabetic model rats

Directory of Open Access Journals (Sweden)

Amrita Bhowmik, Liakot Ali Khan, Masfida Akhter and Begum Rokeya

2009-12-01

Full Text Available Mangifera indica Linn, locally known as mango tree has been claimed to possess antidiabetic properties by many investigators. The present study was undertaken to screen the hypoglycemic and antihyperglycemic activity of both ethanol and water extracts of leaves and stem-barks of M. indica in nondiabetic and diabetic model rats in different prandial state. The results showed that all of the extracts had significant antihyperglycemic effect in type 2 diabetic model rats when fed simultaneously with glucose load (p<0.05-0.01; p<0.005-0.001. Moreover, the ethanol extract of stem-barks showed significant antihyperglycemic effect when the extract was fed 30 min prior to the glucose load (p<0.01. Investigations were carried out to evaluate the effect of M. indica on glucose absorption using a rat intestinal preparation in situ. The ethanol extracts of stem-barks reduced glucose absorption gradually during the whole perfusion period in type 2 diabetic rats.

Phloem Transport of Arsenic Species from Flag Leaf to Grain During Grain Filling

Energy Technology Data Exchange (ETDEWEB)

A Carey; G Norton; C Deacon; K Scheckel; E Lombi; T Punshon; M Guerinot; A Lanzirotti; M Newville; et al.

2011-12-31

Strategies to reduce arsenic (As) in rice grain, below concentrations that represent a serious human health concern, require that the mechanisms of As accumulation within grain be established. Therefore, retranslocation of As species from flag leaves into filling rice grain was investigated. Arsenic species were delivered through cut flag leaves during grain fill. Spatial unloading within grains was investigated using synchrotron X-ray fluorescence (SXRF) microtomography. Additionally, the effect of germanic acid (a silicic acid analog) on grain As accumulation in arsenite-treated panicles was examined. Dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) were extremely efficiently retranslocated from flag leaves to rice grain; arsenate was poorly retranslocated, and was rapidly reduced to arsenite within flag leaves; arsenite displayed no retranslocation. Within grains, DMA rapidly dispersed while MMA and inorganic As remained close to the entry point. Germanic acid addition did not affect grain As in arsenite-treated panicles. Three-dimensional SXRF microtomography gave further information on arsenite localization in the ovular vascular trace (OVT) of rice grains. These results demonstrate that inorganic As is poorly remobilized, while organic species are readily remobilized, from leaves to grain. Stem translocation of inorganic As may not rely solely on silicic acid transporters.

Phloem transport of arsenic species from flag leaf to grain during grain filling

Energy Technology Data Exchange (ETDEWEB)

Carey, Anne-Marie; Norton, Gareth J.; Deacon, Claire; Scheckel, Kirk G.; Lombi, Enzo; Punshon, Tracy; Guerinot, Mary Lou; Lanzirotti, Antonio; Newville, Matt; Choi, Yongseong; Price, Adam H.; Meharg, Andrew A. (EPA); (U. South Australia); (Aberdeen); (UC); (Dartmouth)

2011-09-20

Strategies to reduce arsenic (As) in rice grain, below concentrations that represent a serious human health concern, require that the mechanisms of As accumulation within grain be established. Therefore, retranslocation of As species from flag leaves into filling rice grain was investigated. Arsenic species were delivered through cut flag leaves during grain fill. Spatial unloading within grains was investigated using synchrotron X-ray fluorescence (SXRF) microtomography. Additionally, the effect of germanic acid (a silicic acid analog) on grain As accumulation in arsenite-treated panicles was examined. Dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) were extremely efficiently retranslocated from flag leaves to rice grain; arsenate was poorly retranslocated, and was rapidly reduced to arsenite within flag leaves; arsenite displayed no retranslocation. Within grains, DMA rapidly dispersed while MMA and inorganic As remained close to the entry point. Germanic acid addition did not affect grain As in arsenite-treated panicles. Three-dimensional SXRF microtomography gave further information on arsenite localization in the ovular vascular trace (OVT) of rice grains. These results demonstrate that inorganic As is poorly remobilized, while organic species are readily remobilized, from leaves to grain. Stem translocation of inorganic As may not rely solely on silicic acid transporters.

Transgenic rice plants harboring an introduced potato proteinase inhibitor II gene are insect resistant.

Science.gov (United States)

Duan, X; Li, X; Xue, Q; Abo-el-Saad, M; Xu, D; Wu, R

1996-04-01

We introduced the potato proteinase inhibitor II (PINII) gene (pin2) into several Japonica rice varieties, and regenerated a large number of transgenic rice plants. Wound-inducible expression of the pin2 gene driven by its own promoter, together with the first intron of the rice actin 1 gene (act1), resulted in high-level accumulation of the PINII protein in the transgenic plants. The introduced pin2 gene was stably inherited in the second, third, and fourth generations, as shown by molecular analyses. Based on data from the molecular analyses, several homozygous transgenic lines were obtained. Bioassay for insect resistance with the fifth-generation transgenic rice plants showed that transgenic rice plants had increased resistance to a major rice insect pest, pink stem borer (Sesamia inferens). Thus, introduction of an insecticidal proteinase inhibitor gene into cereal plants can be used as a general strategy for control of insect pests.

Response of nitrogen-fixing water fern Azolla biofertilization to rice crop.

Science.gov (United States)

Bhuvaneshwari, K; Singh, Pawan Kumar

2015-08-01

The water fern Azolla harbors nitrogen-fixing cyanobacterium Anabaena azollae as symbiont in its dorsal leaves and is known as potent N 2 fixer. Present investigation was carried out to study the influence of fresh Azolla when used as basal incorporation in soil and as dual cropped with rice variety Mahsoori separately and together with and without chemical nitrogen fertilizer in pots kept under net house conditions. Results showed that use of Azolla as basal or dual or basal plus dual influenced the rice crop positively where use of fern as basal plus dual was superior and served the nitrogen requirement of rice. There was marked increase in plant height, number of effective tillers, dry mass and nitrogen content of rice plants with the use of Azolla and N-fertilizers alone and other combinations. The use of Azolla also increased organic matter and potassium contents of the soil.

Thin layer chromatography fingerprint, antioxidant, and antibacterial activities of rhizomes, stems, and leaves of Curcuma aeruginosa Roxb.

Science.gov (United States)

Safitri, A.; Batubara, I.; Khumaida, N.

2017-05-01

Fingerprints of 5 temu hitam (Curcuma aeruginosa Roxb.) accessions (Malang, Cirebon, Kuningan 1, Bogor, and Liwa) were determined by thin-layer chromatography (TLC) and compared to fingerprints of turmeric (Curcuma longa L), temu putih (Curcuma zedoaria (Christm.) Roscoe), and temu lawak (Curcuma zanthorriza Roxb.). Maceration method with ethanol as the solvent was used for extraction. The eluent used for fingerprint by TLC was chloroform:dichloromethane (9:1v/v). Five accessions of temu hitam show similar fingerprint patterns, but different in band thickness. Temu hitam rhizomes have bands of curcuminoid (Rf 0.22, 0.10, 0.03), and characteristic bands of Rf 0.42, 0.27, and 0.77, which can be distinguished from turmeric and temu lawak and Rf 0.13, which is different from temu putih. Leaves and stems of temu hitam can be distinguished from temu putih, turmeric, and temu lawak at Rf 0.60. Rhizomes of all plants reveal strong antibacterial activity against Staphylococcus aureus and antioxidant activity on DPPH radicals than its corresponding stems and leaves. Antibacterial and antioxidant activities were determined by microdilution and TLC-bioautography. Antibacterial activity of rhizomes of Cirebon and Kuningan 1 accessions are higher than that of other accessions (MIC = 250 μg/mL MBC = 500 μg/mL, but lower as compared to that of temu lawak (MIC = 62.5 μg/mL, MBC = 250 μg/mL) and tetracycline (MIC = MBC = 15.63 μg/mL). Rhizome of Liwa accession exhibits the highest antioxidant activity (IC50 = 124.88 μg/mL) amongst all accessions, but lower than that of temu lawak (IC50 = 18.45 μg/mL), turmeric (IC50 = 18.82 μg/mL), and temu putih (IC50 = 94.35 μg/mL).

Levels of polonium-210 in the grapevine leaves in Alasehir district in Turkey

International Nuclear Information System (INIS)

Gurboga, G.; Aytas Oelmez, S.

2001-01-01

The objective of present work is the estimation of Po-210 (polonium) content in the edible grapevine leaves (Vitis viniferae, L.cv Sultana syn.) collected from Gediz plain in Western Turkey. Alasehir District in Gediz plain is one of the most important wine culture region of Turkey. Grapevine leaves are important food material for Dolma in Turkish cuisine. Dolma is a name applied to such vegetables as grapevine leaves, cabbage leaves and green peppers stuffed ground meat or spiked rice. Levels of Po-210 in the grapevine leaves had not been analyzed before in Turkey. In this study, after wet ashing of grapevine leaves, Po-210 was spontaneously plated onto a copper disc from dilute hydrochloric acid medium and deposited activity was measured. The results for Po-210 in the grapevine leaves are compared with the other foodstuff values in the literature

Interaction between sulfur and lead in toxicity, iron plaque formation and lead accumulation in rice plant.

Science.gov (United States)

Yang, Junxing; Liu, Zhiyan; Wan, Xiaoming; Zheng, Guodi; Yang, Jun; Zhang, Hanzhi; Guo, Lin; Wang, Xuedong; Zhou, Xiaoyong; Guo, Qingjun; Xu, Ruixiang; Zhou, Guangdong; Peters, Marc; Zhu, Guangxu; Wei, Rongfei; Tian, Liyan; Han, Xiaokun

2016-06-01

Human activities have resulted in lead and sulfur accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of S supply on iron plaque formation and Pb accumulation in rice (Oryza sativa L.) under two Pb levels (0 and 600 mg kg(-1)), combined with four S concentrations (0, 30, 60, and 120 mg kg(-1)). Results showed that S supply significantly decreased Pb accumulation in straw and grains of rice. This result may be attributed to the enhancement of Fe plaque formation, decrease of Pb availability in soil, and increase of reduced glutathione (GSH) in rice leaves. Moderate S supply (30 mg kg(-1)) significantly increased Fe plaque formation on the root surface and in the rhizosphere, whereas excessive S supply (60 and 120 mg kg(-1)) significantly decreased the amounts of iron plaque on the root surface. Sulfur supply significantly enhanced the GSH contents in leaves of rice plants under Pb treatment. With excessive S application, the rice root acted as a more effective barrier to Pb accumulation compared with iron plaque. Excessive S supply may result in a higher monosulfide toxicity and decreased iron plaque formation on the root surface during flooded conditions. However, excessive S supply could effectively decrease Pb availability in soils and reduce Pb accumulation in rice plants. Copyright © 2016 Elsevier Inc. All rights reserved.

Photosynthetic characterization of a rolled leaf mutant of rice ( Oryza ...

African Journals Online (AJOL)

A new rolling leaf rice mutant was identified which showed an apparently straighter longitudinal shape normal transverse rolling characters at all developing stages. The chlorophyll contents per fresh weight of this mutant leaves were lower than those of wild-type. The electron transfer rate (ETR) and photochemical ...

Down-regulation of OsSPX1 causes high sensitivity to cold and oxidative stresses in rice seedlings.

Directory of Open Access Journals (Sweden)

Chunchao Wang

Full Text Available Rice SPX domain gene, OsSPX1, plays an important role in the phosphate (Pi signaling network. Our previous work showed that constitutive overexpression of OsSPX1 in tobacco and Arabidopsis plants improved cold tolerance while also decreasing total leaf Pi. In the present study, we generated rice antisense and sense transgenic lines of OsSPX1 and found that down-regulation of OsSPX1 caused high sensitivity to cold and oxidative stresses in rice seedlings. Compared to wild-type and OsSPX1-sense transgenic lines, more hydrogen peroxide accumulated in seedling leaves of OsSPX1-antisense transgenic lines for controls, cold and methyl viologen (MV treatments. Glutathione as a ROS scavenger could protect the antisense transgenic lines from cold and MV stress. Rice whole genome GeneChip analysis showed that some oxidative-stress marker genes (e.g. glutathione S-transferase and P450s and Pi-signaling pathway related genes (e.g. OsPHO2 were significantly down-regulated by the antisense of OsSPX1. The microarray results were validated by real-time RT-PCR. Our study indicated that OsSPX1 may be involved in cross-talks between oxidative stress, cold stress and phosphate homeostasis in rice seedling leaves.

Rice monitoring with multi-temporal and dual-polarimetric TerraSAR-X data

Science.gov (United States)

Koppe, Wolfgang; Gnyp, Martin L.; Hütt, Christoph; Yao, Yinkun; Miao, Yuxin; Chen, Xinping; Bareth, Georg

2013-04-01

This study assesses the use of TerraSAR-X data for monitoring rice cultivation in the Sanjiang Plain in Heilongjiang Province, Northeast China. The main objective is the understanding of the coherent co-polarized X-band backscattering signature of rice at different phenological stages in order to retrieve growth status. For this, multi-temporal dual polarimetric TerraSAR-X High Resolution SpotLight data (HH/VV) as well as single polarized StripMap (VV) data were acquired over the test site. In conjunction with the satellite data acquisition, a ground truth field campaign was carried out. The backscattering coefficients at HH and VV of the observed fields were extracted on the different dates and analysed as a function of rice phenology to provide a physical interpretation for the co-polarized backscatter response in a temporal and spatial manner. Then, a correlation analysis was carried out between TerraSAR-X backscattering signal and rice biomass of stem, leaf and head to evaluate the relationship with different vertical layers within the rice vegetation. HH and VV signatures show two phases of backscatter increase, one at the beginning up to 46 days after transplanting and a second one from 80 days after transplanting onwards. The first increase is related to increasing double bounce reflection from the surface-stem interaction. Then, a decreasing trend of both polarizations can be observed due to signal attenuation by increasing leaf density. A second slight increase is observed during senescence. Correlation analysis showed a significant relationship with different vertical layers at different phenological stages which prove the physical interpretation of X-band backscatter of rice. The seasonal backscatter coefficient showed that X-band is highly sensitive to changes in size, orientation and density of the dominant elements in the upper canopy.

Studies on the physiological changes in the rice plants infected with Xanthomonas campestris pv. oryzae, (3)

International Nuclear Information System (INIS)

Watanabe, Minoru; Samejima, Shin-ichi; Hosokawa, Daijiro

1980-01-01

Accumulation of 14 C-photosynthetic assimilates in rice leaves infected with Xanthomonas campestris pv. oryzae was studied by using autoradiography for the purpose of elucidating the movement of nutrients from healthy tissues to the infected parts. When rice plants were exposed to 14 CO 2 immediately after inoculation, 14 C-photosynthetic assimilates did not accumulate in and around the inoculated spots of leaves until the lesions became visible, i.e., approximately 7 days after inoculation. When the leaves were exposed to 14 CO 2 before visible lesions appeared, 2 and 5 days after inoculation, the assimilates did not accumulate in the inoculated areas, but apparently accumulated in the lesions 24 hr later on from the exposure of leaves with visible lesions. In the newly formed lesions, accumulation site corresponded to the yellow streak parts of lesions along leaf veins. In the large and old lesions, assimilates hardly any accumulated in the center of lesions, grayish-white in color, but accumulated in the border parts of lesions adjacent to healthy tissues which are developing and yellow streak in symptoms. (author)

Rice- and butterfly-wing effect inspired self-cleaning and low drag micro/nanopatterned surfaces in water, oil, and air flow

Science.gov (United States)

Bixler, Gregory D.; Bhushan, Bharat

2013-12-01

In search of new solutions to complex challenges, researchers are turning to living nature for inspiration. For example, special surface characteristics of rice leaves and butterfly wings combine the shark skin (anisotropic flow leading to low drag) and lotus leaf (superhydrophobic and self-cleaning) effects, producing the so-called rice and butterfly wing effect. In this paper, we study four microstructured surfaces inspired by rice leaves and fabricated with photolithography techniques. We also present a method of creating such surfaces using a hot embossing procedure for scaled-up manufacturing. Fluid drag, self-cleaning, contact angle, and contact angle hysteresis data are presented to understand the role of sample geometrical dimensions. Conceptual modeling provides design guidance when developing novel low drag, self-cleaning, and potentially antifouling surfaces for medical, marine, and industrial applications.

Application of two-stream model to solar radiation of rice canopy

International Nuclear Information System (INIS)

Kawakata, T.

2005-01-01

The amount of solar radiation absorbed by a crop canopy is correlated with crop production, and thus it is necessary to estimate both transmission and reflection around the canopy for crop growth models. The 'forward and backward streams' representation of radiation has been refined to account for both transmission and reflection in the crop canopy. However, this model has not been applied to a rice canopy through the growing period. The purpose of this study is to examine whether the two-stream model is applicable to the rice canopy, and to investigate the parameters of the model. The values for both transmittance below the rice canopy and reflectance above it that were derived from the two-stream model represent the observed values throughout the growing period. The inclination factor of leaves (F), which is used in the two-stream model, was almost equivalent to the extinction coefficient of transmittance in the case of the rice canopy

Estimation of rice situation index in Japan using remotely sensed and meteorological data

International Nuclear Information System (INIS)

Kaneko, D.

2006-01-01

This research aims to develop a remote sensing method for monitoring rice production in Japan. A photosynthesis-based crop production index CPI for rice is proposed that takes into consideration the solar radiation, the effective air temperature, and normalized vegetation index NDVI as a factor representing vegetation biomass. The CPI index incorporates temperature influences such as the effect of temperature on photosynthesis by grain plant leaves, low-temperature effects of sterility, cool summer damage due to delayed growth, and high-temperature injury. These latter factors are significant at around the heading period of rice. The CPI index for rice was modeled at ten monitoring sites in the Kanto, Tohoku, and Hokkaido districts, which occasionally tend to suffer poor harvests as a result of low temperatures. The photosynthesis-based crop production index CPI proposed here can predict the crop situation index of rice by using NDVI, solar radiation at meteorological observatories and air temperature at AMeDAS sites. The method is based on routine observation data, allowing automated monitoring of rice situation index at arbitrary sites in Japan. However, it is possible to further refine the estimation formula for the rice situation index for early monitoring

Absorption and translocation of phosphorus-32 in guava leaves

International Nuclear Information System (INIS)

Natale, William

1997-01-01

Phosphorus is easily absorbed by the leaves and translocated. The objective of this work was to evaluate the absorption and translocation of P by guava leaves, with time. When a solution containing 2% MAP and specific activity 0.15 μCi/ml was applied. MAP labelled with 32 P was applied in the 3 rd pair of leaves. These and other leaves, roots and stem were collected separately and analyzed accordingly. The results showed that 20 days after application 12% of the applied P was absorbed by the guava leaves. The translocation of P started immediately after its absorption reaching 20% 2fter 20 days. (author). 19 refs., 4 tabs

Effects of cobalt-60 low doses radiation on beam, rice and radish seeds

International Nuclear Information System (INIS)

Kikuchi, O.K.

1987-01-01

The effects of cobalt-60 gamma radiation on seeds of bean (Phaseolus vulgaris L.), rice (Oryza sativa L.) and radish (Raphanus sativus L.) were studied. Bean and rice seeds were irradiated with 3.5 and 7.7 Gy (32 Gy/h). There was an apparent acceleration on rice seed germination with 3.5 Gy when they were stored for 6 days after irradiation, but the same dose caused a delay when the store time was 1 day. Bean seeds germination was not modified by 3.5 and 7.7 Gy, but the fresh and dry weight of young plants showed an increase, mainly due the major quantity of water in the embryonic axis. Bean seeds were irradiated with 0.5 and 2.0 Gy (30 Gy/h). Seeds germination showed a slight delay irradiating with 0.5 Gy, while height, fresh and dry weight and primary leaves area of the young plants as well as number of nodes, leaves, flowers, beans and seeds were not modified after irradiation with 0.5 and 2.0 Gy. Radish seeds irradiated with 10 and 30 Gy at dose rates of 4.5, 22.5 and 45.0 Gy/h showed a germination delay and fresh and dry weight values for young plants leaves lower than control. Roots of totally developed plants showed no modifications in weight, volume, mean diameter, lenght and in the amount of soluble reducing sugar. (author)

Dose-dependent response of Trichoderma harzianum in improving drought tolerance in rice genotypes.

Science.gov (United States)

Pandey, Veena; Ansari, Mohammad W; Tula, Suresh; Yadav, Sandep; Sahoo, Ranjan K; Shukla, Nandini; Bains, Gurdeep; Badal, Shail; Chandra, Subhash; Gaur, A K; Kumar, Atul; Shukla, Alok; Kumar, J; Tuteja, Narendra

2016-05-01

This study demonstrates a dose-dependent response of Trichoderma harzianum Th-56 in improving drought tolerance in rice by modulating proline, SOD, lipid peroxidation product and DHN / AQU transcript level, and the growth attributes. In the present study, the effect of colonization of different doses of T. harzianum Th-56 strain in rice genotypes were evaluated under drought stress. The rice genotypes treated with increasing dose of T. harzianum strain Th-56 showed better drought tolerance as compared with untreated control plant. There was significant change in malondialdehyde, proline, higher superoxide dismutase level, plant height, total dry matter, relative chlorophyll content, leaf rolling, leaf tip burn, and the number of scorched/senesced leaves in T. harzianum Th-56 treated rice genotypes under drought stress. This was corroborated with altered expression of aquaporin and dehydrin genes in T. harzianum Th-56 treated rice genotypes. The present findings suggest that a dose of 30 g/L was the most effective in improving drought tolerance in rice, and its potential exploitation will contribute to the advancement of rice genotypes to sustain crop productivity under drought stress. Interaction studies of T. harzianum with three aromatic rice genotypes suggested that PSD-17 was highly benefitted from T. harzianum colonization under drought stress.

Nutrient allocation among stem, leaf and inflorescence of jatropha plants

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Rosiane L. S. de Lima

2015-08-01

Full Text Available ABSTRACTInformation on the partitioning of nutrients among various organs in jatropha plants, as a complementary tool for the recommendation of fertilization, is still not available. This study aimed to evaluate the contents of macro and micronutrients in stems, leaves and inflorescences of jatropha branches at the beginning of flowering. At the beginning of flowering, adult jatropha plants were sampled and divided into five compartments: inflorescences, leaves from vegetative branches, leaves from flowering branches, stems from vegetative branches and stems from flowering branches. Jatropha inflorescences are a drain of nutrients. Leaves are important sources of nutrients demanded by the inflorescences at the beginning of flowering. The higher allocation of nutrients in the inflorescences suggests the need for preventive/corrective fertilizations, which must be performed at least 30 days before flowering, providing plants with nutrients in adequate amounts for a good yield.

Carbon isotope discrimination and yield of upland rice as affected by drought at flowering

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PINHEIRO BEATRIZ DA SILVEIRA

2000-01-01

Full Text Available Field experiments involving upland rice genotypes, sown in various dates in late season, were carried out to assess the relationship of carbon isotope discrimination with grain yield and drought resistance. In each one of the three years, one trial was kept under good water availability, while other suffered water shortage for a period of 18-23 days, encompassing panicle emergence and flowering. Drought stress reduced carbon isotope discrimination measured on soluble sugars (deltas extracted from stem uppermost internode at the end of the imposition period, but had relatively less effect on bulk dry matter of leaves, sampled at the same period, or that of uppermost internodes and grains, sampled at harvest. The drought-induced reduction in deltas was accompanied of reduced spikelet fertility and grain yield. In the three trials subjected to drought, genotypes with the highest yield and spikelet fertility had the lowest deltas. However, this relationship was weak and it was concluded that deltas is not a sufficiently reliable indicator of rice drought resistance to be useful as a screening test in breeding programs. On the other hand, grain yield and spikelet fertility of genotypes which were the soonest to reach 50% flowering within the drought imposition period, were the least adversely affected by drought. Then, timing of drought in relation to panicle emergence and to flowering appeared to be a more important cause of yield variation among genotypes than variation in deltas.

Studies on control of yellow stem borer, Tryporyza incertulas, a serious pest of paddy. Part of a coordinated programme on the use of pest management with emphasis on rice insects

International Nuclear Information System (INIS)

Rahalkar, G.W.

1982-03-01

Egg parasitism is the chief biotic factor regulating paddy stem borer populations. However, effective suppression of the borer through their natural enemies is not evident in practice. Studies were undertaken to evaluate the feasibility of releasing sterile yellow stem borer females into the field to increase host egg densities as these females would lay nonviable eggs. (a) Paddy fields were surveyed for the incidence of egg parasitism. (b) Attempts were made to rear yellow stem borer larvae on cut stem pieces of field grown rice plants. (c) Trichogramma japonicum, the natural egg parasite of the stem borer was reared in the laboratory using eggs of Corcyra cephalonica and Ephestia cautella as alternate host material. Mass rearing of yellow stem borer larvae on paddy plants grown under laboratory conditions does not appear practically feasible. Borer larvae reared on cut stem pieces with intact roots did not yield satisfactory adults as far as their reproductive behaviour was concerned. Though some of the dietary compositions contained natural host material, they failed to support the larval establishment. Probably some highly specific phagostimulants need to be incorporated in the diets. T. japonicum could be reared on radiation killed Ephestia eggs. The female parasite was unable to discriminate between eggs laid by radiation sterilized host females and those laid by normal ones

Identification of phasiRNAs in wild rice (Oryza rufipogon).

Science.gov (United States)

Liu, Yang; Wang, Yu; Zhu, Qian-Hao; Fan, Longjiang

2013-08-01

Plant miRNAs can trigger the production of phased, secondary siRNAs from either non-coding or protein-coding genes. In this study, at least 864 and 3,961 loci generating 21-nt and 24-nt phased siRNAs (phasiRNAs),respectively, were identified in three tissues from wild rice. Of these phasiRNA-producing loci, or PHAS genes, biogenesis of phasiRNAs in at least 160 of 21-nt and 254 of 24-nt loci could be triggered by interaction with miRNA(s). Developing seeds had more PHAS genes than leaves and roots. Genetic constrain on miRNA-triggered PHAS genes suggests that phasiRNAs might be one of the driving forces contributed to rice domestication.

Isoenzymes performance of some rice varieties and their mutants

International Nuclear Information System (INIS)

Winarno, Ermin; Suliwarno, Ambyah; Ismachin, M.

1992-01-01

Isoenzymes performance of some rice varieties and their mutants. Genetics studies on alcohol dehydrogenase, malic enzyme, peroxidase, acid phosphase, and aminopeptidase isoenzymes were carried out on several groups of rice varieties and their mutant lines. The first groups consisted of Atomita I, Pelita I/1, A227/5, Mudgo, TN-1, and IR-26. The second group was Cisadane variety and its five mutants, namely OBS 18, OBS 208, OBS 297, OBS 306, and OBS 330. The third group was mutants line 627-10-3 and its mutants, namely 1063, 1066, 1067, 1076, and 1090. Isoenzymes extracts of the rice leaves were fractionated using polyacrylamide gel disc electrophoresis. The pattern of acid phosphate isoenzyme shows the specific character of rice mutants susceptible to brown plant hopper biotype 1. The gene(s) controlling malic enzyme in Cisadane's mutants is (are) estimated more resistant toward gamma irradiation than gene(s) responsible for controlling the other enzymes. Generally, the isoenzymes zymograms show that gene(s) controlling the mutants enzyme have undergone mutation. This case is shown by the changes of Rm value, as well as the amount and intensity of mutants bands. (authors). 7 refs., 7 figs

Alterations in carbon and nitrogen metabolism induced by water deficit in the stems and leaves of Lupinus albus L.

Science.gov (United States)

Pinheiro, C; Chaves, M M; Ricardo, C P

2001-05-01

Water deficit (WD) in Lupinus albus L. brings about tissue-specific responses that are dependent on stress intensity. Carbohydrate metabolism is very sensitive to changes in plant water status. Six days from withholding water (DAW), sucrose, glucose and fructose levels of the leaf blade had already increased over 5-fold, and the activities of SS and INV(A) had increased c. 1.5-2 times. From 9 DAW on, when stress intensity was more pronounced, these effects were reversed with fructose and glucose concentrations as well as INV(A) activity dropping in parallel. The stem (specifically the stele) responded to the stress intensification with striking increases in the concentration of sugars, N and S, and in the induction of thaumatin-like-protein and an increase in chitinase and peroxidase. At 13 DAW, the plants lost most of the leaves but on rewatering they fully recovered. Thus, the observed changes appear to contribute to a general mechanism of survival under drought, the stem playing a key role in that process.

Optimizing hill seeding density for high-yielding hybrid rice in a single rice cropping system in South China.

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Danying Wang

Full Text Available Mechanical hill direct seeding of hybrid rice could be the way to solve the problems of high seeding rates and uneven plant establishment now faced in direct seeded rice; however, it is not clear what the optimum hill seeding density should be for high-yielding hybrid rice in the single-season rice production system. Experiments were conducted in 2010 and 2011 to determine the effects of hill seeding density (25 cm×15 cm, 25 cm×17 cm, 25 cm×19 cm, 25 cm×21 cm, and 25 cm×23 cm; three to five seeds per hill on plant growth and grain yield of a hybrid variety, Nei2you6, in two fields with different fertility (soil fertility 1 and 2. In addition, in 2012 and 2013, comparisons among mechanical hill seeding, broadcasting, and transplanting were conducted with three hybrid varieties to evaluate the optimum seeding density. With increases in seeding spacing from 25 cm×15 cm to 25 cm×23 cm, productive tillers per hill increased by 34.2% and 50.0% in soil fertility 1 and 2. Panicles per m2 declined with increases in seeding spacing in soil fertility 1. In soil fertility 2, no difference in panicles per m2 was found at spacing ranging from 25 cm×17 cm to 25 cm×23 cm, while decreases in the area of the top three leaves and aboveground dry weight per shoot at flowering were observed. Grain yield was the maximum at 25 cm×17 cm spacing in both soil fertility fields. Our results suggest that a seeding density of 25 cm×17 cm was suitable for high-yielding hybrid rice. These results were verified through on-farm demonstration experiments, in which mechanical hill-seeded rice at this density had equal or higher grain yield than transplanted rice.

Phenotyping of VIGS-mediated gene silencing in rice using a vector derived from a DNA virus.

Science.gov (United States)

Kant, Ravi; Dasgupta, Indranil

2017-07-01

Target genes in rice can be optimally silenced if inserted in antisense or hairpin orientation in the RTBV-derived VIGS vector and plants grown at 28 °C and 80% humidity after inoculation. Virus induced gene silencing (VIGS) is a method used to transiently silence genes in dicot as well as monocot plants. For the important monocot species rice, the Rice tungro bacilliform virus (RTBV)-derived VIGS system (RTBV-VIGS), which uses agroinoculation to initiate silencing, has not been standardized for optimal use. Here, using RTBV-VIGS, three sets of conditions were tested to achieve optimal silencing of the rice marker gene phytoene desaturase (pds). The effect of orientation of the insert in the RTBV-VIGS plasmid (sense, antisense and hairpin) on the silencing of the target gene was then evaluated using rice magnesium chelatase subunit H (chlH). Finally, the rice Xa21 gene, conferring resistance against bacterial leaf blight disease (BLB) was silenced using RTBV-VIGS system. In each case, real-time PCR-based assessment indicated approximately 40-80% fall in the accumulation levels of the transcripts of pds, chlH and Xa21. In the case of pds, the appearance of white streaks in the emerging leaves, and for chlH, chlorophyll levels and F v /F m ratio were assessed as phenotypes for silencing. For Xa21, the resistance levels to BLB were assessed by measuring the lesion length and the percent diseased areas of leaves, following challenge inoculation with Xanthomonas oryzae. In each case, the RTBV-MVIGS system gave rise to a discernible phenotype indicating the silencing of the respective target gene using condition III (temperature 28 °C, humidity 80% and 1 mM MES and 20 µM acetosyringone in secondary agrobacterium culture), which revealed the robustness of this gene silencing system for rice.

SALINITY TOLERANCE OF SEVERAL RICE GENOTYPES AT SEEDLING STAGE

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Heni Safitri

2018-01-01

Full Text Available Salinity is one of the most serious problems in rice cultivation. Salinity drastically reduced plant growth and yield, especially at seedling stage. Several rice genotypes have been produced, but their tolerance to salinity has not yet been evaluated. The study aimed to evaluate salinity tolerance of rice genotypes at seedling stage. The glasshouse experiment was conducted at Cimanggu Experimental Station, Bogor, from April to May 2013. Thirteen rice genotypes and two check varieties, namely Pokkali (salt tolerant and IR29 (salt sensitive were tested at seedling stage. The experiment was arranged in a randomized complete block design with three replications and two factors, namely the levels of NaCl (0 and 120 mM and 13 genotypes of rice. Rice seedlings were grown in the nutrient culture (hydroponic supplemented with NaCl at different levels. The growth and salinity injury levels of the genotypes were recorded periodically. The results showed that salinity level of 120 mM NaCl reduced seedling growth of all rice genotypes, but the tolerant ones were survived after 14 days or until the sensitive check variety died. Based on the visual injury symptoms on the leaves, five genotypes, i.e. Dendang, Inpara 5, Inpari 29, IR77674-3B-8-2-2-14-4-AJY2, and IR81493-BBB-6-B- 2-1-2 were tolerant to 120 mM salinity level, while Inpara 4 was comparable to salt sensitive IR29. Hence, Inpara 4 could be used as a salinity sensitive genotype for future research of testing tolerant variety. Further evaluation is needed to confirm their salinity tolerance under field conditions. 

Establishment of a rice-duck integrated farming system and its effects on soil fertility and rice disease control

Science.gov (United States)

Teng, Qing; Hu, Xue-Feng; Cheng, Chang; Luo, Zhi-Qing; Luo, Fan

2015-04-01

Rice-duck integrated farming is an ecological farming system newly established in some areas of southern China . It was reported that the ducks walking around the paddy fields is beneficial to control weed hazards and reduce rice pests and diseases. To study and evaluate the effects of the rice-duck integrated farming on soil fertility and rice disease control, a field experiment of rice cultivation was carried out in the suburb of Shanghai in 2014. It includes a treatment of raising ducks in the fields and a control without ducks. The treatment was implemented by building a duck coop nearby the experimental fields and driving 15 ducks into a plot at daytime since the early stage of rice growth. Each plot is 667 m2 in area. The treatment and control were replicated for three times. No any herbicides, pesticides, fungicides and chemical fertilizers were applied during the experiment to prevent any disturbance to duck growing and rice weed hazards and disease incidences from agrochemicals. The results are as follows: (1) The incidences of rice leaf rollers (Cnaphalocrocis medinalis) and stem borers treated with ducks, 0.45%and 1.18% on average, respectively, are lower than those of the control, 0.74% and 1.44% on average, respectively. At the late stage of rice growth, the incidence of rice sheath blight treated with ducks, 13.15% on average, is significantly lower than that of the control, 16.9% on average; and the incidence of rice planthoppers treated with ducks, 11.3 per hill on average, is also significantly lower than that of the control, 47.4 per hill on average. (2) The number of weeds in the plots treated with ducks, 8.3 per m2 on average, is significantly lower than that of the control, 87.5 m2 on average. (3) Raising ducks in the fields could also enhance soil enzyme activity and nutrient status. At the late stage of rice growth, the activities of urease, phosphatase, sucrase and catalase in the soils treated with ducks are 1.39 times, 1.40 times, 1

OsWRKY53, a versatile switch in regulating herbivore-induced defense responses in rice

OpenAIRE

Hu, Lingfei; Ye, Meng; Li, Ran; Lou, Yonggen

2016-01-01

ABSTRACT WRKY proteins, which belong to a large family of plant-specific transcription factors, play important roles in plant defenses against pathogens and herbivores by regulating defense-related signaling pathways. Recently, a rice WRKY transcription factor OsWRKY53 has been reported to function as a negative feedback modulator of OsMPK3/OsMPK6 and thereby to control the size of the investment a rice plant makes to defend against a chewing herbivore, the striped stem borer Chilo suppressal...

Effect of fertilizer application and deep rooting measures on the absorption of 137Cs by rice

International Nuclear Information System (INIS)

Zhu Yongyi; Yang Juncheng; Chen Jingjian; Liu Xuelian; Xu Yinliang; Sun Zhiming

1998-01-01

Effects of the application of phosphorus and potassium fertilizer and deep rooting on reducing the absorption of 137 Cs by rice (especially in the seed) were estimated using pot and plot experiment. The results show that the available 137 Cs in soil decreased significantly by applying potassium fertilizer, which led to the lower accumulation of 137 Cs in rice stem and the most effective measure was to apply potassium sulphate of 922.5 kg/ha. An unsteady effect with phosphate fertilizer existed. When P application was in a lower amount, the accumulation of 137 Cs in rice decreased. But following the increase of P application, the absorption of 137 Cs was promoted. The 137 Cs accumulation in rice decreased significantly by deep rooting

Alteration in caesium behavior in rice caused by the potassium, phosphorous, and nitrogen deficiency

International Nuclear Information System (INIS)

Tatsuya Nobori; Kobayashi, N.I.; Keitaro Tanoi; Nakanishi, T.M.

2016-01-01

The physiological effects of critical nutrient deficiencies (K, P, N) on the uptake of caesium (Cs) and impact on plant growth has been investigated in rice plants. Growth defects were observed after 2 weeks of a state of nutrient starvation (K, P, or N). However, only K starvation produced increased Cs content in the shoot and the intensive transport to young leaves. These observations support that modification of Cs uptake and transport in rice plants was achieved based on the distinctive physiological effect of K. (author)

A Rice Gene Homologous to Arabidopsis AGD2-LIKE DEFENSE1 Participates in Disease Resistance Response against Infection with Magnaporthe oryzae

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Ga Young Jung

2016-08-01

Full Text Available ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1 is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

Consumption of Bt Rice Pollen Containing Cry1C or Cry2A Protein Poses a Low to Negligible Risk to the Silkworm Bombyx mori (Lepidoptera: Bombyxidae)

Science.gov (United States)

Yang, Yan; Liu, Yue; Cao, Fengqin; Chen, Xiuping; Cheng, Lisheng; Romeis, Jörg; Li, Yunhe; Peng, Yufa

2014-01-01

By consuming mulberry leaves covered with pollen from nearby genetically engineered, insect-resistant rice lines producing Cry proteins derived from Bacillus thuringiensis (Bt), larvae of the domestic silkworm, Bombyx mori (Linnaeus) (Lepidoptera: Bombyxidae), could be exposed to insecticidal proteins. Laboratory experiments were conducted to assess the potential effects of Cry1C- or Cry2A-producing transgenic rice (T1C-19, T2A-1) pollen on B. mori fitness. In a short-term assay, B. mori larvae were fed mulberry leaves covered with different densities of pollen from Bt rice lines or their corresponding near isoline (control) for the first 3 d and then were fed mulberry leaves without pollen. No effect was detected on any life table parameter, even at 1800 pollen grains/cm2 leaf, which is much higher than the mean natural density of rice pollen on leaves of mulberry trees near paddy fields. In a long-term assay, the larvae were fed Bt and control pollen in the same way but for their entire larval stage (approximately 27 d). Bt pollen densities ≥150 grains/cm2 leaf reduced 14-d larval weight, increased larval development time, and reduced adult eclosion rate. ELISA analyses showed that 72.6% of the Cry protein was still detected in the pollen grains excreted with the feces. The low exposure of silkworm larvae to Cry proteins when feeding Bt rice pollen may be the explanation for the relatively low toxicity detected in the current study. Although the results demonstrate that B. mori larvae are sensitive to Cry1C and Cry2A proteins, the exposure levels that harmed the larvae in the current study are far greater than natural exposure levels. We therefore conclude that consumption of Bt rice pollen will pose a low to negligible risk to B. mori. PMID:25014054

Alleviatory effects of silicon on the foliar micromorphology and anatomy of rice (Oryza sativa L.) seedlings under simulated acid rain.

Science.gov (United States)

Ju, Shuming; Wang, Liping; Zhang, Cuiying; Yin, Tingchao; Shao, Siliang

2017-01-01

Silicon (Si) is a macroelement in plants. The biological effects and mitigation mechanisms of silicon under environmental stress have become hot topics. The main objectives of this study were to elucidate the roles of Si in alleviating the effects on the phenotype, micromorphology and anatomy of the leaves of rice seedlings under acid rain stress. The results indicated that the combined or single effects of Si and simulated acid rain (SAR) stress on rice roots depended on the concentration of Si and the intensity of the SAR stress. The combined or single effects of the moderate concentration of Si (2.0 mM) and light SAR (pH 4.0) enhanced the growth of the rice leaves and the development of the mesophyll cells, and the combined effects were stronger than those of the single treatments. The high concentration of Si (4.0 mM) and severe SAR (pH 3.0 or 2.0) exerted deleterious effects. The incorporation of Si (2.0 or 4.0 mM) into SAR at pH values of 3.0 or 2.0 promoted rice leaf growth, decreased necrosis spots, maintained the structure and function of the mesophyll cells, increased the epicuticular wax content and wart-like protuberance (WP) density, and improved the stomatal characteristics of the leaves of rice seedlings more than the SAR only treatments. The alleviatory effects observed with a moderate concentration of Si (2.0 mM) were better than the effects obtained with the high concentration of Si (4.0 mM). The alleviatory effects were due to the enhancement of the mechanical barriers in the leaf epidermis.

Alleviatory effects of silicon on the foliar micromorphology and anatomy of rice (Oryza sativa L.) seedlings under simulated acid rain

Science.gov (United States)

Ju, Shuming; Wang, Liping; Zhang, Cuiying; Yin, Tingchao; Shao, Siliang

2017-01-01

Silicon (Si) is a macroelement in plants. The biological effects and mitigation mechanisms of silicon under environmental stress have become hot topics. The main objectives of this study were to elucidate the roles of Si in alleviating the effects on the phenotype, micromorphology and anatomy of the leaves of rice seedlings under acid rain stress. The results indicated that the combined or single effects of Si and simulated acid rain (SAR) stress on rice roots depended on the concentration of Si and the intensity of the SAR stress. The combined or single effects of the moderate concentration of Si (2.0 mM) and light SAR (pH 4.0) enhanced the growth of the rice leaves and the development of the mesophyll cells, and the combined effects were stronger than those of the single treatments. The high concentration of Si (4.0 mM) and severe SAR (pH 3.0 or 2.0) exerted deleterious effects. The incorporation of Si (2.0 or 4.0 mM) into SAR at pH values of 3.0 or 2.0 promoted rice leaf growth, decreased necrosis spots, maintained the structure and function of the mesophyll cells, increased the epicuticular wax content and wart-like protuberance (WP) density, and improved the stomatal characteristics of the leaves of rice seedlings more than the SAR only treatments. The alleviatory effects observed with a moderate concentration of Si (2.0 mM) were better than the effects obtained with the high concentration of Si (4.0 mM). The alleviatory effects were due to the enhancement of the mechanical barriers in the leaf epidermis. PMID:29065171

Evaluation of Protocols for Measuring Leaf Photosynthetic Properties of Field-Grown Rice

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Chang Tian-gen

2017-01-01

Full Text Available Largely due to the heterogeneity of environmental parameters and the logistical difficulty of moving photosynthetic equipment in the paddy fields, effective measurement of lowland rice photosynthesis is still a challenge. In this study, we showed that measuring detached rice leaves in the laboratory can not effectively represent the parameters measured in situ. We further described a new indoor facility, high-efficiency all-weather photosynthetic measurement system (HAPS, and the associated measurement protocol to enable whole-weather measurement of photosynthetic parameters of rice grown in the paddy fields. Using HAPS, we can conduct photosynthetic measurements with a time span much longer than that appropriate for the outdoor measurements. Comparative study shows that photosynthetic parameters obtained with the new protocol can effectively represent the parameters in the fields. There was much less standard deviation for measurements using HAPS compared to the outdoor measurements, no matter for technical replications of each recording or for biological replications of each leaf position. This new facility and protocol enables rice photosynthetic physiology studies to be less tough but more efficient, and provides a potential option for large scale studies of rice leaf photosynthesis.

Application of perennial legume green manures to improve growth and yield of organic lowland rice

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M Winarni

2016-10-01

Full Text Available A pot experiment in green house was done to study the effect of the dosage and speciesof perennial legume green manures to the physiological traits, growth and yield of organic lowland rice (Oryza sativaL., and to obtain the optimal dosage as well.  The research was arranged in a factorial randomized block design consistedof two factors with three replications.The first factor was the species of perennial legume thatconsisted of threespecies: Turi (Sesbaniagrandiflora, Glirisidia (Gliricidiasepium, and Lamtoro (Leucaenaleucocephala and cow manure as control treatment. The second factor was the dosage of green manure thatconsisted of four levels: 5, 10, 20 and 40 t/ha.  The results showed that application ofperennial legumesinto the soil significantly improved the growth and yield of rice.  The application of  20 t Glirisidia leaves/haproduced the highest grain yield, followed by 20 t Lamtoro leaves/ha and 20 t Turi leaves/ha.  The optimal dosages of S. grandiflora, G. sepium and L. leucochepala leaves that could yield 58.03 g/hill (equivalent to14.51 t/ha, 53.67 g/hill (equivalent to 13.42 t/ha, and 49.67 g/hill (equivalent to 12.42 t/ha were 28.05, 25.46 and 26.41 t/ha, respectively.

In vitro antileishmanial and cytotoxicity activities of essential oils from Haplophyllum tuberculatum A. Juss leaves, stems and aerial parts.

Science.gov (United States)

Hamdi, Assia; Bero, Joanne; Beaufay, Claire; Flamini, Guido; Marzouk, Zohra; Vander Heyden, Yvan; Quetin-Leclercq, Joelle

2018-02-14

Plants used for traditional medicine produce diverse and complex secondary metabolites exhibiting various medicinal properties. The medicinal plant Haplophyllum tuberculatum is used by native people against malaria and parasitic infections. In this study and in order to contribute for the search of new natural drugs for leishmaniasis, the essential oils of H. tuberculatum leaves, stems and aerial parts (leaves+stems) collected in two different periods, 2013 and 2015, and their components by GC/FID and GC/MS analyses were investigated. Those collected in 2013 were also re-analyzed two years later. The extracted oils were screened in vitro for anti-leishmanial activity on Leishmania mexicana mexicana (L.m.m.) promastigotes and cytotoxicity on the Chinese Hamster Ovary (CHO) cell line. Limonene (1.5 - 8%), its isomers (R- (+)-limonene and S-(-)-limonene), linalool and octanol were also tested. Results showed that the chemical composition varied according to the year of collection. Though major compounds remain almost the same, qualitative and quantitative variations in the composition of the EOs can be observed between the two years of collection, with some minor compounds identified only in one type of samples. Variation in the composition were also observed in the re-analyzed volatile oils, showing stability concerns. The essential oils and R-(+)-limonene showed moderate anti-leishmanial activity. Their IC 50 range from 6.48 to 50.28 μg/ml. Cytotoxicity assays for theses volatile extracts, R- (+)-limonene and S- (-)-limonene on CHO cells showed relatively potent cytotoxicity with a selectivity index <10. Their CC 50 range from 27.79 to 82.56 μg/ml. The findings of the present study demonstrated that H. tuberculatum might not be considered as a natural source for production of new anti-leishmanial agents without further analyzing its eventual in vivo toxicity as well as that of major pure compounds.

Biomass distribution efficiency of rose cv. Charlotte grown in soil and substrates at second production peak

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María Y González G

2013-12-01

Full Text Available Growing plants in substrates is an alternative for the production of roses under unfavorable soil conditions. The objective of this study was to determine the biomass distribution efficiency of rose cv. Charlotte grown in soil and substrates under greenhouse conditions until second production peak. In this trial, soil and substrates with 100% burned rice husk (100BR H; 65% burned rice husk: 35% coconut fiber (65BR H; 35% burned rice husk: 65% coconut fiber (35BR H; and 100% coconut fiber (100CF were used. The experimental design consisted of a randomized complete block design with three repetitions. Destructive sampling was carried out using whole plants and flowering stems at previously determined bud stages. Leaf area and dry matter in organs were measured and growth rate and physiological indexes were calculated. The assessed variables were fitted to logistic and exponential models. The plants grown in substrates with BR H (burned rice husk showed similar values regarding dry matter and fresh weight accumulation in organs. Plants in the soil treatment were the last ones to reach the different development stages of the flowering buds, while those that were grown in 100CF were the first ones. The treatments 35BR H and 100CF showed less growth of flowering stems, which was expressed in terms of relative dry matter increase per day. The plants grown in soil showed more dry matter in leaves and stems but less in flower buds. The 65BR H treatment showed some of the highest dry matter accumulations in leaves, stems and flower buds and also showed the highest leaf area ratio, leaf weight ratio, and specific leaf area values

Identification of some Rice Mutants using Morphological and Molecular Methods

International Nuclear Information System (INIS)

Sobieh, S.E.S.

2006-01-01

This investigation was conducted at the experimental farm of plant research department, nuclear research center, atomic energy authority, abu zaabal in order to verify four rice genotypes i.e sakha 102, giza 178, high yielding mutant (Ms 6) and high yielding mutant (MG 16). the (UPOV) rice descriptor was used to identify the germplasm morphologically .Molecular RAPD-PCR was used to identify genetic variability on the molecular level for the tested genotypes. 1- the results indicated that according to (UPOV) rice descriptor eight morphological traits were completely different between mutant Ms 6 in comparison with the parent sakha 102 and mut. MG 16 in comparison parent giza 178, the traits were ; stem thickness, stem length, panicle length, 1000-grain weight, grain length, grain width decorticated grain length and decorticated grain width. 2- using 10 arbitrary primers, through four rice genotypes on the molecular level using RAPD markers. the size of the amplified fragments were ranged from 0.201 to 2.036 k bp. two primers OPB-13 and OPB-16 showed no polymorphism among genotypes tested. 3- the total number of amplicons produced by the 8 polymorphic RAPD profiels was 66. the total number of monomorphic amplicons was 32. however, the total number of polymorphic amplicons was 34. 4- the percentage of polymorphism ranged from (22.22%) for primer OPA-18 to (90%) for primer OPB-11. 5-the highest genetic similarity (90.3%) was between sakha 102 and high yielding mut. (Ms 6). the genetic similarity (75.5%) was between giza 178 and high yielding mut.(MG 16). 6- one positive unique marker amplified by OPA-18 Primer identified the high yielding mutant Ms 6 but three positive unique markers amplified by OPB-17 primer and OPA-18 primer identified the high yielding mutant MG 16

Pattern of photosynthesis in saline indica var. of rice Kala Rata

International Nuclear Information System (INIS)

Hegde, B.A.; Joshi, G.V.

1975-01-01

The present investigation on Kala Rata deals with the pattern of photosynthesis and the salt stress effect on the photosynthetic efficiency in rice. It is evident from the investigation that chlorophyll synthesis is enhanced with the increasing concentration of NaCl in the bathing medium. However, the efficiency of photosynthesis does not increase with increased chlorophyll production. All ions in leaves can stimulate CO 2 incorporation but inhibit at higher concentration. Analysis of short term products of photosynthesis revealed that aspartate is the major product to be heavily labelled which is evident from autoradiogram. PGA has also appreciable label, where as, malate has the least. It appears therefore, that in rice, both, Calvin as well as C 4 type of pathways are operating. 'Aspartate former' type of rice does not seem to be efficient in photosynthesis as it has C 3 pathway also in operation. (author)

Rice status and microwave characteristics: Analysis of rice paddy fields at Kojima Bay [Okayama, Japan] using multi-frequency and polarimetric Pi-SAR radar data images

International Nuclear Information System (INIS)

Ishitsuka, N.; Saito, G.; Ouchi, K.; Davidson, G.; Mohri, K.; Uratsuka, S.

2003-01-01

Abstract South-east Asia has a rainy-season at the crop growing period, and it is difficult to observe agricultural land in this season using optical remote sensing. Synthetic Aperture Radar (SAR) can observe the earth's surface without being influenced by of clouds. However, it is less useful for observing agricultural land, because satellite SAR has only one data band. Recently, SAR is able to provide multi band and multi polarimetric data. Pi-SAR, an airborne SAR developed by NASDA and CRL, can provide L and X bands and fully polarimetric data. Rice is the main crop in Asia, and we studied the characteristic microwave scatter on rice paddy fields using Pi-SAR data. Our study area was the rice paddy fields in Kojima reclaimed land in Japan. We had two fully polarimetric data sets from 13 July 1999 and 4 October 2000. First, we processed the color polarimetric composite image. Next we calibrated the phase of each polarimetric data using river area by the Kimura method. After that we performed decomposition analysis and drew polarimetric signatures for understanding the status of rice paddy fields. At the rice planting period, rice paddy fields are filled with water and rice plants are very small. The SAR microwave scatters on water surfaces like a mirror, called 'mirror (or specular) reflection'. This phenomenon makes backscatter a small value at the water-covered area. The image from July is about one month after trans-planting and rice plants are 20-40 cm in height. X-band microwave scatters on the rice surface, but L-band microwave passes through rice bodies and shows mirror refraction on water surfaces. Some strong backscatter occur on rice paddy fields especially VV polarization because of bragg scattering. The fields where bragg scattering returns strong VV scatter because the space between rice stems cause resonation in the L-band wavelength. We can easily understand bragg scatter by using polarimetric data. Using the image from October at

Os11Gsk gene from a wild rice, Oryza rufipogon improves yield in rice.

Science.gov (United States)

Thalapati, Sudhakar; Batchu, Anil K; Neelamraju, Sarla; Ramanan, Rajeshwari

2012-06-01

Chromosomal segments from wild rice species Oryza rufipogon, introgressed into an elite indica rice restorer line (KMR3) using molecular markers, resulted in significant increase in yield. Here we report the transcriptome analysis of flag leaves and fully emerged young panicles of one of the high yielding introgression lines IL50-7 in comparison to KMR3. A 66-fold upregulated gene Os11Gsk, which showed no transcript in KMR3 was highly expressed in O. rufipogon and IL50-7. A 5-kb genomic region including Os11Gsk and its flanking regions could be PCR amplified only from IL50-7, O. rufipogon, japonica varieties of rice-Nipponbare and Kitaake but not from the indica varieties, KMR3 and Taichung Native-1. Three sister lines of IL50-7 yielding higher than KMR3 showed presence of Os11Gsk, whereas the gene was absent in three other ILs from the same cross having lower yield than KMR3, indicating an association of the presence of Os11Gsk with high yield. Southern analysis showed additional bands in the genomic DNA of O. rufipogon and IL50-7 with Os11Gsk probe. Genomic sequence analysis of ten highly co-expressed differentially regulated genes revealed that two upregulated genes in IL50-7 were derived from O. rufipogon and most of the downregulated genes were either from KMR3 or common to KMR3, IL50-7, and O. rufipogon. Thus, we show that Os11Gsk is a wild rice-derived gene introduced in KMR3 background and increases yield either by regulating expression of functional genes sharing homology with it or by causing epigenetic modifications in the introgression line.

Study on creation and utilization of induced mutation rice materials

International Nuclear Information System (INIS)

Pang Aijun; Peng Weizheng; Pang Boliang; Peng Xuanming; Yang Zhen; Zhang Xianxin; Zhang Yuanhai

2011-01-01

60 Co γ-ray, spaceflight, laser were respectively or combinedly used to treat rice lines or hybrid materials. Many special type of seed breed lines, including high yielding ones, top quality ones, stunt stem ones, disease/pest resistent ones, colourful rices, big size of grain ones etc. were selected from the mutation materials, some were directly used as new varieties and some were indirectly used to breed hybrid varieties. All the new varieties such as 'xiangzaonuo No.1', 'xiangzaoxian No.20', 'xiangzaoxian No.21', 'xiangfu 994', 'peiliangyou 721', 'zhuliangyou 124' were popularly planted and great social and economical benefit was obtained. (authors)

Evaluating Sheath Blight Resistance in Rice Using Detached Tiller and Field Screening Method

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Bedanand Chaudhary

2015-12-01

Full Text Available In present study physical resistance test on 12 rice varieties against sheath blight (ShB caused by Rhizoctonia solani was examined. A detached tiller test was used to measure components of ShB physiological resistance at Regional Agricultural Research Station (RARS, Tarahara, Nepal. The varieties were evaluated in a randomized complete block design (RCBD with 3 replications in year 2010-12. A sclerotium was inserted below the leaf collar of individual tillers maintained in tubes filled with water. Only the 56-day old susceptible plants were inoculated. After 7 days of inoculation, number of lesions, dead leaves, vertical sheath colonization and disease severity were measured. In 2011, field experiments were conducted with three replications to address morphological resistance in 28 rice genotypes. Disease incidence was recorded on 14, 21 and 28 days after inoculation. The number of dead leaves differed only numerically while disease variables significantly (P=0.004 varied among varieties. The other variables were highly correlated with each other. Cluster analysis of variables formed three varietal groups; Sabitri with lowest, and Jasmine-85 and Betichikon having highest values. Rice genotypes differed significantly (P=0.05 for disease incidence and area Under Disease Progress Curve (AUDPC. Tetep and IAC-165 had the lowest and highest terminal disease incidences and AUDPC, respectively. Sabitri, MTU-1010 and IR-26 recorded lower AUDPC values. Hence, Tetep and Sabitri could be used as donors in hybridization and their plant morphology could be considered as selection guide for improving ShB resistance in rice.

Photosynthetic /sup 14/CO/sub 2/ fixation in the leaves of rice and some other species

Energy Technology Data Exchange (ETDEWEB)

Ishii, R; Samejima, M; Murata, Y [Tokyo Univ. (Japan). Faculty of Agriculture

1977-03-01

The activity of CO/sub 2/-fixing enzymes and the initial products of photosynthetic /sup 14/CO/sub 2/ fixation in two rice varieties, the one japonica and the other indica, were examined, comparing with those in several C/sub 3/ and C/sub 4/ crop species. Corn and barnyard grass as C/sub 4/ plants and barley and wheat as C/sub 3/ plants were used as comparison materials. The plants were cultured at 25 deg. C in daytime and 20 deg. C in night under natural light in a phytotron. After about a month from sowing, the fully expanded leaf blades were subjected to the experiments. The fresh leaf blades of one gram were homogenized in 5 ml of 50 mM Tris-H/sub 2/SO/sub 4/ buffer (pH 7.7) containing 4 mM EDTA, 10 mM dithiothreitol and 50 mg of polyamide powder. After filtration, the supernatant was used as the crude enzyme extract for assaying the activity of RuDP carboxylase and PEP carboxylase. The experiments revealed that (1) in C/sub 3/ plants, the RuDP carboxylase activity was higher, and the PEP carboxylase activity was lower than those in C/sub 4/ plants; (2) the initial products of photosynthetic /sup 14/CO/sub 2/ fixation in the japonica rice variety were mainly PGA and other sugar phosphates as in barley, whereas in corn, they were malic and aspartic acids; (3) the /sup 14/C incorporation into glycine and serine was high in the japonica rice and barley, whereas low in corn. From these results, rice could be regarded as C/sub 3/ plant.

The Commonly Used Bactericide Bismerthiazol Promotes Rice Defenses against Herbivores

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Pengyong Zhou

2018-04-01

Full Text Available Chemical elicitors that enhance plant resistance to pathogens have been extensively studied, however, chemical elicitors that induce plant defenses against insect pests have received little attention. Here, we found that the exogenous application of a commonly used bactericide, bismerthiazol, on rice induced the biosynthesis of constitutive and/or elicited jasmonic acid (JA, jasmonoyl-isoleucine conjugate (JA-Ile, ethylene and H2O2 but not salicylic acid. These activated signaling pathways altered the volatile profile of rice plants. White-backed planthopper (WBPH, Sogatella furcifera nymphs and gravid females showed a preference for feeding and/or oviposition on control plants: survival rates were better and more eggs were laid than on bismerthiazol-treated plants. Moreover, bismerthiazol treatment also increased both the parasitism rate of WBPH eggs laid on plants in the field by Anagrus nilaparvatae, and also the resistance of rice to the brown planthopper (BPH Nilaparvata lugens and the striped stem borer (SSB Chilo suppressalis. These findings suggest that the bactericide bismerthiazol can induce the direct and/or indirect resistance of rice to multiple insect pests, and so can be used as a broad-spectrum chemical elicitor.

Gibberellin biosynthesis and signal transduction is essential for internode elongation in deepwater rice.

Science.gov (United States)

Ayano, Madoka; Kani, Takahiro; Kojima, Mikiko; Sakakibara, Hitoshi; Kitaoka, Takuya; Kuroha, Takeshi; Angeles-Shim, Rosalyn B; Kitano, Hidemi; Nagai, Keisuke; Ashikari, Motoyuki

2014-10-01

Under flooded conditions, the leaves and internodes of deepwater rice can elongate above the water surface to capture oxygen and prevent drowning. Our previous studies showed that three major quantitative trait loci (QTL) regulate deepwater-dependent internode elongation in deepwater rice. In this study, we investigated the age-dependent internode elongation in deepwater rice. We also investigated the relationship between deepwater-dependent internode elongation and the phytohormone gibberellin (GA) by physiological and genetic approach using a QTL pyramiding line (NIL-1 + 3 + 12). Deepwater rice did not show internode elongation before the sixth leaf stage under deepwater condition. Additionally, deepwater-dependent internode elongation occurred on the sixth and seventh internodes during the sixth leaf stage. These results indicate that deepwater rice could not start internode elongation until the sixth leaf stage. Ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the phytohormone contents showed a deepwater-dependent GA1 and GA4 accumulation in deepwater rice. Additionally, a GA inhibitor abolished deepwater-dependent internode elongation in deepwater rice. On the contrary, GA feeding mimicked internode elongation under ordinary growth conditions. However, mutations in GA biosynthesis and signal transduction genes blocked deepwater-dependent internode elongation. These data suggested that GA biosynthesis and signal transduction are essential for deepwater-dependent internode elongation in deepwater rice. © 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

Effect of drying conditions on drying kinetics and quality of aromatic Pandanus amaryllifolius leaves

OpenAIRE

Rayaguru, Kalpana; Routray, Winny

2010-01-01

Pandanus amaryllifolius is a plant with aromatic leaves, which impart the characteristic flavour of aromatic rice. The quality of aromatic Pandanus leaves dried at low temperature (35 °C) and low RH (27%) in a heat pump dryer was evaluated and compared with those obtained from hot air drying at 45 °C. Thin-layer drying kinetics has been studied for both the conditions. To determine the kinetic parameters, the drying data were fitted to various semi-theoretical models. The goodness of fit was ...

Quantitative determination of total and individual flavonoids in stems and leaves of Buddleja davidii and Buddleja albiflora.

Science.gov (United States)

Ying, Cheng; Wan, Dingrong

2012-10-01

Buddleja davidii and B. albiflora are two different original plants of the famous crude medicine "Diaoyangchen". An ultraviolet-visible spectrophotometric method and a HPLC method were used for the determination of total and individual flavonoids (luteolin and apigenin) contents from their stems and leaves for the first time. From the comparative evaluation, remarkable differences in flavonoids contents were observed between different origins and different parts of the samples. And content of specific flavonoid did not correspond to the total flavonoids contents in Buddleja davidii and Buddleja albiflora. With a better accuracy and precision, the methods had been proved simple, rapid, and reliable for quantitative determination of the total flavonoids and luteolin and apigenin in the two phytomedicines. Furthermore, our present study will pave the way of guidelines for the differentiation and standardization and exploitation of individual parts of this herb material.

Risk assessment and vertical distribution of thallium in paddy soils and uptake in rice plants irrigated with acid mine drainage.

Science.gov (United States)

Huang, Xuexia; Li, Ning; Wu, Qihang; Long, Jianyou; Luo, Dinggui; Zhang, Ping; Yao, Yan; Huang, Xiaowu; Li, Dongmei; Lu, Yayin; Liang, Jianfeng

2016-12-01

The objective of this paper is to assess the influence of irritating paddy fields with acid mine drainage containing thallium (Tl) to rice plant-soil system and potential health risks for local residents. Vertical distribution of Tl, pH, organic matter (OM), and cation exchange capacity (CEC) in 24 paddy soil profiles around Yunfu pyrite mine area was investigated. Rice plant samples were collected from the corresponding soil sampling site. The results showed that Tl concentrations in paddy soils at 0-60 cm depth range from 3.07 to 9.42 mg kg -1 , with a mean of 5.74 mg kg -1 , which were significantly higher than the background value of soil in China (0.58 mg kg -1 ). On the whole, Tl contents in paddy soil profiles increased quickly with soil depth from 0 to 30 cm and decreased slowly with soil depth from 30 to 60 cm. The soil Tl content was significant negatively correlated with soil pH. The mean content of Tl in the root, stem, leaf, and rice was 4.36, 1.83, 2.74, and 1.42 mg kg -1 , respectively, which exceeded the proposed permissible limits for foods and feedstuffs in Germany. The Tl content in various tissues of the rice plants followed the order root > leaf > stem (rice), which suggested that most Tl taken up by rice plants retained in the root, and a little migrated to the leaf, stem, and rice. Correlation analysis showed that Tl content in root was significant positively correlated with Tl content in leaf and rice. The ranges of hazard quotient (HQ) values were 4.08∼24.50 and 3.84∼22.38 for males and females, respectively. Males have higher health risk than females in the same age group. In childhood age groups (2 to <21 years) and adult age groups (21 to <70 years), the highest health risk level was observed in the 11 to 16 age group and 21 to 50 age group, respectively. The findings indicated that regular irrigation with Tl-bearing acid mine drainage led to considerable contamination of Tl in paddy soil and rice plant. Local government

Lead (Pb) Toxicity; Physio-Biochemical Mechanisms, Grain Yield, Quality, and Pb Distribution Proportions in Scented Rice.

Science.gov (United States)

Ashraf, Umair; Kanu, Adam S; Deng, Quanquan; Mo, Zhaowen; Pan, Shenggang; Tian, Hua; Tang, Xiangru

2017-01-01

Lead (Pb) caused interruptions with normal plant metabolism, crop yield losses and quality issues are of great concern. This study assessed the physio-biochemical responses, yield and grain quality traits and Pb distribution proportions in three different fragrant rice cultivars i.e., Meixiangzhan-2, Xinagyaxiangzhan and Basmati-385. Plants were exposed to 400, 800, and 1,200 ppm of Pb while pots without Pb were taken as control (0 ppm). Our results showed that Pb toxicity significantly ( P production of hydrogen peroxide (H 2 O 2 ), malanodialdehyde (MDA) and leaves leachates; while such effects were more apparent in Xinagyaxiangzhan than other two rice cultivars. Pb stress differentially affected the production protein, proline and soluble sugars; however the production rates were higher at heading stage (HS) than maturity stage (MS). Furthermore, Pb stress altered superoxide dismutase (SOD), peroxidases (POD), catalases (CAT) and ascorbate peroxidases (APX) activities and glutathione (GSH) and oxidized glutathione (GSSG) production in all rice cultivars at both HS and MS. All Pb levels reduced the yield and yield components of all rice cultivars; nonetheless such reductions were observed highest in Xinagyaxiangzhan (69.12%) than Meixiangzhan-2 (58.05%) and Basmati-385 (46.27%) and resulted in grain quality deterioration. Significant and positive correlations among rice yields with productive tillers/pot and grains per panicle while negative with sterility percentage were also observed. In addition, all rice cultivars readily taken up the Pb contents from soil to roots and transported upward in different proportions with maximum in roots followed by stemss, leaves, ears and grains. Higher proportions of Pb contents in above ground plant parts in Xinagyaxiangzhan possibly lead to maximum losses in this cultivar than other two cultivars; while less damage in Basmati-385 might be related to strong anti-oxidative defense system and lower proportions of Pb contents in

Regulation of glutamine synthetase isoforms in two differentially drought-tolerant rice (Oryza sativa L.) cultivars under water deficit conditions.

Science.gov (United States)

Singh, Kamal Krishna; Ghosh, Shilpi

2013-02-01

KEY MESSAGE : The regulation of GS isoforms by WD was organ specific. Two GS isoforms i.e. OsGS1;1 and OsGS2 were differentially regulated in IR-64 (drought-sensitive) and Khitish (drought-tolerant) cultivars of rice. Water deficit (WD) has adverse effect on rice (Oryza sativa L.) and acclimation requires essential reactions of primary metabolism to continue. Rice plants utilize ammonium as major nitrogen source, which is assimilated into glutamine by the reaction of Glutamine synthetase (GS, EC 6.3.1.2). Rice plants possess one gene (OsGS2) for chloroplastic GS2 and three genes (OsGS1;1, OsGS1;2 and OsGS1;3) for cytosolic GS1. Here, we report the effect of WD on regulation of GS isoforms in drought-sensitive (cv. IR-64) and drought-tolerant (cv. Khitish) rice cultivars. Under WD, total GS activity in root and leaf decreased significantly in IR-64 seedlings in comparison to Khitish seedlings. The reduced GS activity in IR-64 leaf was mainly due to decrease in GS2 activity, which correlated with decrease in corresponding transcript and polypeptide contents. GS1 transcript and polypeptide accumulated in leaf during WD, however, GS1 activity was maintained at a constant level. Total GS activity in stem of both the varieties was insensitive to WD. Among GS1 genes, OsGS1;1 expression was differently regulated by WD in the two rice varieties. Its transcript accumulated more abundantly in IR-64 leaf than in Khitish leaf. Following WD, OsGS1;1 mRNA level in stem and root tissues declined in IR-64 and enhanced in Khitish. A steady OsGS1;2 expression patterns were noted in leaf, stem and root of both the cultivars. Results suggest that OsGS2 and OsGS1;1 expression may contribute to drought tolerance of Khitish cultivar under WD conditions.

Autophagy supports biomass production and nitrogen use efficiency at the vegetative stage in rice.

Science.gov (United States)

Wada, Shinya; Hayashida, Yasukzu; Izumi, Masanori; Kurusu, Takamitsu; Hanamata, Shigeru; Kanno, Keiichi; Kojima, Soichi; Yamaya, Tomoyuki; Kuchitsu, Kazuyuki; Makino, Amane; Ishida, Hiroyuki

2015-05-01

Much of the nitrogen in leaves is distributed to chloroplasts, mainly in photosynthetic proteins. During leaf senescence, chloroplastic proteins, including Rubisco, are rapidly degraded, and the released nitrogen is remobilized and reused in newly developing tissues. Autophagy facilitates the degradation of intracellular components for nutrient recycling in all eukaryotes, and recent studies have revealed critical roles for autophagy in Rubisco degradation and nitrogen remobilization into seeds in Arabidopsis (Arabidopsis thaliana). Here, we examined the function of autophagy in vegetative growth and nitrogen usage in a cereal plant, rice (Oryza sativa). An autophagy-disrupted rice mutant, Osatg7-1, showed reduced biomass production and nitrogen use efficiency compared with the wild type. While Osatg7-1 showed early visible leaf senescence, the nitrogen concentration remained high in the senescent leaves. (15)N pulse chase analysis revealed suppression of nitrogen remobilization during leaf senescence in Osatg7-1. Accordingly, the reduction of nitrogen available for newly developing tissues in Osatg7-1 likely led its reduced leaf area and tillers. The limited leaf growth in Osatg7-1 decreased the photosynthetic capacity of the plant. Much of the nitrogen remaining in senescent leaves of Osatg7-1 was in soluble proteins, and the Rubisco concentration in senescing leaves of Osatg7-1 was about 2.5 times higher than in the wild type. Transmission electron micrographs showed a cytosolic fraction rich with organelles in senescent leaves of Osatg7-1. Our results suggest that autophagy contributes to efficient nitrogen remobilization at the whole-plant level by facilitating protein degradation for nitrogen recycling in senescent leaves. © 2015 American Society of Plant Biologists. All Rights Reserved.

Radiation use efficiency of rice under different planting methods and environmental conditions

International Nuclear Information System (INIS)

Apakupakul, R.

1995-01-01

Radiation use efficiency is an important parameter which has often been used in many crop growth models to estimate total biomass and yield. Studies of the relationships between above-ground biomass and accumulative absorbed photosynthetically active radiation (PARa, MJ/square m) of rice were examined both on-farms and on-station in Phatthalung. Planting methods were wet-sown and transplanted rice for Suphanburi 90 in the 1993 dry season and Chieng in the 1993-94 wet season. Solar radiation of the two growing seasons were calculated from climatic data. The objectives of this experiment were (1) to know the pattern of relationship between above-ground biomass and accumulative absorbed PAR of rice cultivars grown in South Thailand, (2) to compare the radiation use efficiency of rice cultivars under different planting methods and (3) to obtain the primary data for rice growth modelling in the southern climate. Results presented that only the duration of first growing period up to stem elongation in both cultivars, above-ground biomass and leaf area index were higher in wet-sown than in transplanted rice. Relationship between above-ground biomass accumulation through growing period and accumulative absorbed PAR was in positive linear regression with R*[2)0.85. Erect leaf of Suphanburi 90 had a radiation use efficiency (RUE, g/MJ) higher than non-erect leaf of Chieng. A problem of weed infestation in wet-sown rice in both cultivars had an effect on the RUE which were highly significant lower than transplanted rice. The Rue of wet-sown and transplanted rice were 2.77 and 3.20 g/MJ, respectively for Suphanburi 90, 2.13 and 2.67 g/MJ for Chieng. These results suggest that when dealing with radiation use efficiency in the rice growth modelling the differences of cultivars and planting methods should be taken into consideration

Involvement of Antioxidative Defense System in Rice Seedlings Exposed to Aluminum Toxicity and Phosphorus Deficiency

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Tian-rong GUO

2012-09-01

Full Text Available Plants growing in acid soils may suffer both phosphorus (P deficiency and aluminum (Al toxicity. Hydroponic experiments were undertaken to assess the single and combination effects of Al toxicity and low P stress on seedling growth, chlorophyll and proline contents, antioxidative response and lipid peroxidation of two rice genotypes (Yongyou 8 and Xiushui 132 differing in Al tolerance. Al toxicity and P deficiency both inhibited rice seedling growth. The development of toxic symptoms was characterized by reduced chlorophyll content, increased proline and malondialdehyde contents in both roots and leaves, and increased peroxidase and superoxide dismutase activities in roots, but decreased in leaves. The stress condition induced more severe growth inhibition and oxidative stress in Yongyou 8, and Xiushui 132 showed higher tolerance to both Al toxicity and P deficiency. P deficiency aggravated Al toxicity to plant growth and induced more severe lipid peroxidation.

Studies on the physiological changes in the rice plants infected with Xanthomonas campestris pv. of oryzae, (4)

International Nuclear Information System (INIS)

Watanabe, Minoru; Samejima, Shin-ichi; Hayashi, Nobuo; Hosokawa, Daijiro

1980-01-01

The translocation and accumulation of 14 C-photosynthetic assimilates in rice plants infected with Xanthomonas campestris pv. oryzae were investigated. Approximately the same quantities of assimilates were detected in healthy and infected leaves 1 day after photosynthesis, but 1.7 times as much as healthy leaves assimilates were still remained in infected leaves 7 days after photosynthesis. Much more 14 C-photosynthetic assimilates were generally detected in leaf blade than in leaf sheath or in root within 1 day after photosynthesis, but detected in leaf sheath than in leaf blade later than 2 days after photosynthesis. The rates of translocation of 14 C-assimilates from leaf blade to leaf sheath were lower in inoculated rice plants than in healthy ones. In both healthy and inoculated leaves of susceptible and resistant cultivars, there was a tendency that 14 C-sugar contents decreased, but 14 C-organic acid and -amino acid contents increased gradually after photosynthesis. Incorporation of 14 C-photosynthetic assimilates into invading bacterial cells which were separated from leaf tissues by the methods of leakage and Millipore filtration was not detected immediately after photosynthesis, but became apparent 5 days after photosynthesis. The leakage of 14 C-photosynthetic assimilates from leaf tissues into bathing solution was about 4 times higher in infected leaves than in healthy ones 5 days after photosynthesis, suggesting that the permeability in infected leaf tissues would increase. (author)

Effects of Low Light on Agronomic and Physiological Characteristics of Rice Including Grain Yield and Quality

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Qi-hua LIU

2014-09-01

Full Text Available Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling stage, induces a significant loss in yield and results in poor grain quality. Stress caused by low light often creates severe meteorological disasters in some rice-growing regions worldwide. This review was based on our previous research and related research regarding the effects of low light on rice growth, yield and quality as well as the formation of grain, and mainly reviewed the physiological metabolism of rice plants, including characteristics of photosynthesis, activities of antioxidant enzymes in rice leaves and key enzymes involved in starch synthesis in grains, as well as the translocations of carbohydrate and nitrogen. These characteristics include various grain yield and rice quality components (milling and appearance as well as cooking, eating and nutritional qualities under different rates of shading imposed at the vegetative or reproductive stages of rice plants. Furthermore, we discussed why grain yield and quality are reduced under the low light environment. Next, we summarized the need for future research that emphasizes methods can effectively improve rice grain yield and quality under low light stress. These research findings can provide a beneficial reference for rice cultivation management and breeding program in low light environments.

Effects and mechanisms of meta-sodium silicate amendments on lead uptake and accumulation by rice.

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Zhao, Mingliu; Liu, Yuting; Li, Honghong; Cai, Yifan; Wang, Ming Kuang; Chen, Yanhui; Xie, Tuanhui; Wang, Guo

2017-09-01

The objectives of this research were to study the effects of Na 2 SiO 3 application on the uptake, translocation, and accumulation of Pb in rice and to investigate the mechanisms of Pb immobilization by Na 2 SiO 3 in paddy rice soils and rice plants. Pot experiments were conducted using a Cd-Pb-Zn-polluted soil and Oryza sativa L. ssp. indica cv. Donglian 5. L 3 -edge X-ray absorption spectroscopy was used to identify Pb species in soils and roots. The results showed that the application of Na 2 SiO 3 increased soil pH and available soil Si but decreased DTPA-extractable Pb in the soil. High dose of Na 2 SiO 3 (12.5 g/kg) reduced the Pb level in brown rice as it inhibited Pb transfer from soil to rice grains, especially Pb transfer from the root to the stem. The Pb X-ray absorption near-edge spectroscopic analysis revealed that application of high dose of Na 2 SiO 3 increased Pb-ferrihydrite and PbSiO 3 precipitates in the soil and in the root while it reduced Pb-humic acids (Pb-HAs) in the soil and Pb-pectin in the root. The decrease in Pb availability in the soil can be partly attributed to increase the precipitation of PbSiO 3 and the association of Pb 2+ with Fe oxides in the soil. The inhibition of the root-to-stem translocation of Pb was partially due to the precipitation of PbSiO 3 on the root surfaces or inside the roots.

FON2 SPARE1 redundantly regulates floral meristem maintenance with FLORAL ORGAN NUMBER2 in rice.

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Takuya Suzaki

2009-10-01

Full Text Available CLAVATA signaling restricts stem cell identity in the shoot apical meristem (SAM in Arabidopsis thaliana. In rice (Oryza sativa, FLORAL ORGAN NUMBER2 (FON2, closely related to CLV3, is involved as a signaling molecule in a similar pathway to negatively regulate stem cell proliferation in the floral meristem (FM. Here we show that the FON2 SPARE1 (FOS1 gene encoding a CLE protein functions along with FON2 in maintenance of the FM. In addition, FOS1 appears to be involved in maintenance of the SAM in the vegetative phase, because constitutive expression of FOS1 caused termination of the vegetative SAM. Genetic analysis revealed that FOS1 does not need FON1, the putative receptor of FON2, for its action, suggesting that FOS1 and FON2 may function in meristem maintenance as signaling molecules in independent pathways. Initially, we identified FOS1 as a suppressor that originates from O. sativa indica and suppresses the fon2 mutation in O. sativa japonica. FOS1 function in japonica appears to be compromised by a functional nucleotide polymorphism (FNP at the putative processing site of the signal peptide. Sequence comparison of FOS1 in about 150 domesticated rice and wild rice species indicates that this FNP is present only in japonica, suggesting that redundant regulation by FOS1 and FON2 is commonplace in species in the Oryza genus. Distribution of the FNP also suggests that this mutation may have occurred during the divergence of japonica from its wild ancestor. Stem cell maintenance may be regulated by at least three negative pathways in rice, and each pathway may contribute differently to this regulation depending on the type of the meristem. This situation contrasts with that in Arabidopsis, where CLV signaling is the major single pathway in all meristems.

A Rice Immunophilin Gene, OsFKBP16-3, Confers Tolerance to Environmental Stress in Arabidopsis and Rice

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Jun Cheul Ahn

2013-03-01

Full Text Available The putative thylakoid lumen immunophilin, FKBP16-3, has not yet been characterized, although this protein is known to be regulated by thioredoxin and possesses a well-conserved CxxxC motif in photosynthetic organisms. Here, we characterized rice OsFKBP16-3 and examined the role of this gene in the regulation of abiotic stress in plants. FKBP16-3s are well conserved in eukaryotic photosynthetic organisms, including the presence of a unique disulfide-forming CxxxC motif in their N-terminal regions. OsFKBP16-3 was mainly expressed in rice leaf tissues and was upregulated by various abiotic stresses, including salt, drought, high light, hydrogen peroxide, heat and methyl viologen. The chloroplast localization of OsFKBP16-3-GFP was confirmed through the transient expression of OsFKBP16-3 in Nicotiana benthamiana leaves. Transgenic Arabidopsis and transgenic rice plants that constitutively expressed OsFKBP16-3 exhibited increased tolerance to salinity, drought and oxidative stresses, but showed no change in growth or phenotype, compared with vector control plants, when grown under non-stressed conditions. This is the first report to demonstrate the potential role of FKBP16-3 in the environmental stress response, which may be regulated by a redox relay process in the thylakoid lumen, suggesting that artificial regulation of FKBP16-3 expression is a candidate for stress-tolerant crop breeding.

Stem secondary growth of tundra shrubs

DEFF Research Database (Denmark)

Campioli, Matteo; Leblans, Niki; Michelsen, Anders

2012-01-01

Our knowledge of stem secondary growth of arctic shrubs (a key component of tundra net primary production, NPP) is very limited. Here, we investigated the impact of the physical elements of the environment on shrub secondary growth by comparing annual growth rates of model species from similar...... growth (stem apical growth, stem length, and apical growth of stem plus leaves), in some cases even with opposite responses. Thus caution should be taken when estimating the impact of the environment on shrub growth from apical growth only. Integration of our data set with the (very limited) previously...

Identification and utilization of cleistogamy gene cl7(t) in rice (Oryza sativa L.).

Science.gov (United States)

Ni, Da-Hu; Li, Juan; Duan, Yong-Bo; Yang, Ya-Chun; Wei, Peng-Cheng; Xu, Rong-Fang; Li, Chun-Rong; Liang, Dan-Dan; Li, Hao; Song, Feng-Shun; Ni, Jin-Long; Li, Li; Yang, Jian-Bo

2014-05-01

Gene transformation is an important method for improvement of plants into elite varieties. However, the possibility of gene flow between genetically modified (GM) crops and similar species is a serious public issue that may potentially endanger ecological stability. Cleistogamy is expected to be an ideal genetic tool for preventing transgene propagation from GM crops. A rice mutant, cl7(t), was created by ethyl methanesulfonate mutagenesis. The mutant exhibited cleistogamy, and had closed spikelets, reduced plant height, and altered morphology of the leaves, panicle, and seeds. Anatomical investigations revealed that the cl7(t) mutant contained more vascular bundles and thicker stems than the wild type, which increased the mechanical strength of its internodes, and anti-lodging ability. Further studies demonstrated that the force required to open the lemma and palea was higher in the cl7(t) mutant, and there was weak swelling ability in the lodicules, which leads to cleistogamy. Allelic analyses and complementation tests indicated that cl7(t) was a novel allele of dep2, a mutant that was previously reported to have similar panicle morphology. Sequence analysis showed that cl7(t) had a single nucleotide substitution (C to A) in the third exon that leads to a Ser substitution with a stop codon, giving a truncated DEP2 protein. Quantitative RT-PCR and in situ hybridization tests demonstrated that there was lower CL7(t) expression level in the spikelets and weaker CL7(t) signals in the lodicules of the cl7(t) mutant compared with wild type, which implies that CL7(t) might participate in the development of lodicules. To improve the agronomic traits of cl7(t) to fit the needs of field production, the cl7(t) mutant was crossed with an intermediate-type rice variety named Guanghui102, which bears some important agronomic traits, including increased grain numbers and high rate of seed setting. Through multi-generational pedigree selection, cleistogamy lines with improved

Analysis of Hopi/Osr27 and Houba/Tos5/Osr13 retrotransposons in rice

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Gozde Yuzbasioglu

2016-03-01

Full Text Available We investigated Hopi/Osr27 (gypsy and Houba/Tos5/Osr13 (copy retrotransposon movements in 10-day-old roots and leaves of Oryza sativa cvs. Ipsala, Beser and Osmancik-97. Seeds from these three cultivars were germinated between filter papers in Petri dishes for 10 days. Three biologically independent (nonrelated seeds were germinated for each cultivar. Then, roots and leaves grown from the same rice plant were harvested and used for genomic DNA isolation. Inter-retrotransposon amplified polymorphism–polymerase chain reaction with suitable primers was performed with each DNA template to analyze the movements of Hopi/Osr27 and Houba/Tos5/Osr13 retrotransposons. Polymorphism ratios were evaluated both among cultivars and among roots and leaves from the same cultivar. The polymorphism ratios ranged from 0% to 17% for Hopi/Osr27 and from 10% to 87% for Houba/Tos5/Osr13. The obtained results at retrotransposon and varietal levels indicated that the retrotransposon type and genotype dependence are responsible for the occurrence of different variations. Transposable elements are very important for understanding the relationship between cultivars and evolution. Our findings are expected to contribute to the understanding of spontaneous genomic insertion events and their effects on the genetic and epigenetic changes during rice development.

Grain Unloading of Arsenic Species in Rice

Energy Technology Data Exchange (ETDEWEB)

Carey, Anne-Marie; Scheckel, Kirk G.; Lombi, Enzo; Newville, Matt; Choi, Yongseong; Norton, Gareth J.; Charnock, John M.; Feldmann, Joerg; Price, Adam H.; Meharg, Andrew A. (EPA); (U. South Australia); (Manchester); (Aberdeen); (UC)

2010-01-11

Rice (Oryza sativa) is the staple food for over half the world's population yet may represent a significant dietary source of inorganic arsenic (As), a nonthreshold, class 1 human carcinogen. Rice grain As is dominated by the inorganic species, and the organic species dimethylarsinic acid (DMA). To investigate how As species are unloaded into grain rice, panicles were excised during grain filling and hydroponically pulsed with arsenite, arsenate, glutathione-complexed As, or DMA. Total As concentrations in flag leaf, grain, and husk, were quantified by inductively coupled plasma mass spectroscopy and As speciation in the fresh grain was determined by x-ray absorption near-edge spectroscopy. The roles of phloem and xylem transport were investigated by applying a {+-} stem-girdling treatment to a second set of panicles, limiting phloem transport to the grain in panicles pulsed with arsenite or DMA. The results demonstrate that DMA is translocated to the rice grain with over an order magnitude greater efficiency than inorganic species and is more mobile than arsenite in both the phloem and the xylem. Phloem transport accounted for 90% of arsenite, and 55% of DMA, transport to the grain. Synchrotron x-ray fluorescence mapping and fluorescence microtomography revealed marked differences in the pattern of As unloading into the grain between DMA and arsenite-challenged grain. Arsenite was retained in the ovular vascular trace and DMA dispersed throughout the external grain parts and into the endosperm. This study also demonstrates that DMA speciation is altered in planta, potentially through complexation with thiols.

Rice Seed Priming with Picomolar Rutin Enhances Rhizospheric Bacillus subtilis CIM Colonization and Plant Growth.

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Akanksha Singh

Full Text Available The effect of rutin, a bioflavonoid on the growth and biofilm formation of Bacillus subtilis strain CIM was investigated. In addition to swimming, swarming, and twitching potentials of B. subtilis CIM (BS, one picomolar (1 pM of rutin was also observed to boost the biofilm forming ability of the bacterium. Bio-priming of rice seeds with BS and rutin not only augmented root and shoot lengths but also the photosynthetic pigments like chlorophyll and carotenoid. Similarly, high accumulation of phenolic and flavonoid contents was observed in the leaves. Fluorescent microscopic images revealed that BS plus rutin enhanced callose deposition in the leaves. It was also established that the least formation of reactive oxygen species in BS plus rutin treated rice plants was due to higher free radicals scavenging activity and total antioxidant potential. The results highlight chemo attractant nature of BS towards rutin, which by enhancing biofilm formation and root colonization indirectly strengthened the plants' defensive state.

Transcriptome Analysis of Early Responsive Genes in Rice during Magnaporthe oryzae Infection

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Yiming Wang

2014-12-01

Full Text Available Rice blast disease caused by Magnaporthe oryzae is one of the most serious diseases of cultivated rice (Oryza sativa L. in most rice-growing regions of the world. In order to investigate early response genes in rice, we utilized the transcriptome analysis approach using a 300 K tilling microarray to rice leaves infected with compatible and incompatible M. oryzae strains. Prior to the microarray experiment, total RNA was validated by measuring the differential expression of rice defense-related marker genes (chitinase 2, barwin, PBZ1, and PR-10 by RT-PCR, and phytoalexins (sakuranetin and momilactone A with HPLC. Microarray analysis revealed that 231 genes were up-regulated (>2 fold change, p < 0.05 in the incompatible interaction compared to the compatible one. Highly expressed genes were functionally characterized into metabolic processes and oxidation-reduction categories. The oxidative stress response was induced in both early and later infection stages. Biotic stress overview from MapMan analysis revealed that the phytohormone ethylene as well as signaling molecules jasmonic acid and salicylic acid is important for defense gene regulation. WRKY and Myb transcription factors were also involved in signal transduction processes. Additionally, receptor-like kinases were more likely associated with the defense response, and their expression patterns were validated by RT-PCR. Our results suggest that candidate genes, including receptor-like protein kinases, may play a key role in disease resistance against M. oryzae attack.

Tentative characterization of precursor compounds and co-factors of pigment formation in production of 'wu mi' from Vaccinium bracteatum Thunb. Leaves.

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Fan, Mingcong; Fan, Yihui; Huang, Weiping; Wang, Li; Li, Yan; Qian, Haifeng; Zhang, Hui; Qi, Xiguang

2018-10-01

Vaccinium bracteatum leaves (VBTL) are traditionally used in China to dye rice grains, which assume a deep blue color, named 'Wu mi'. Information on the mechanism of pigment formation is limited. In this study, CIELAB color space parameters were used to represent the color of 'Wu mi'. Precursor compounds of pigments formed during the dyeing process were identified by UPLC Q-TOF MS analysis. The changes in co-factors for pigment formation in VBTL were measured at different growth stages. The L ∗ and b ∗ values of dyed rice increased as the leaves aged, whereas a ∗ values showed irregular changes. Six compounds were tentatively identified as pigment precursors by UPLC Q-TOF MS analysis. The pH and β-glucosidase activity at different growth stages of VBTL were indicated to be crucial co-factors for pigment formation. A tentative hypothesis is presented that iridoid glycosides are hydrolyzed by acids and β-glucosidases to form a dialdehyde structure that binds covalently with amino residues of lysine side chains in rice protein molecules. Copyright © 2018 Elsevier Ltd. All rights reserved.

Carbon isotopic composition of legumes with photosynthetic stems from Mediterranean and desert habitats

International Nuclear Information System (INIS)

Nilsen, E.T.; Sharifi, M.R.

1997-01-01

The carbon isotopic compositions of leaves and stems of woody legumes growing in coastal mediterranean and inland desert sites in California were compared. The overall goal was to determine what factors were most associated with the carbon isotope composition of photosynthetic stems in these habitats. The carbon isotope signature (delta 13C) of photosynthetic stems was less negative than that of leaves on the same plants by an average of 1.51 +/- 0.42 per thousand. The delta 13C of bark (cortical chlorenchyma and epidermis) was more negative than that of wood (vascular tissue and pith) from the same plant for all species studied on all dates. Desert woody legumes had a higher delta 13C (less negative) and a lower intercellular CO2 concentration (Ci) (for both photosynthetic tissues) than that of woody legumes from mediterranean climate sites. Differences in the delta 13C of stems among sites could be entirely accounted for by differences among site air temperatures. Thus, the delta 13C composition of stems did not indicate a difference in whole-plant integrated water use efficiency (WUE) among sites. In contrast, stems on all plants had a lower stem Ci and a higher delta 13C than leaves on the same plant, indicating that photosynthetic stems improve long-term, whole-plant water use efficiency in a diversity of species

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

International Nuclear Information System (INIS)

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

2010-01-01

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

Collection of rice mutants and application studies of their agronomic characters

International Nuclear Information System (INIS)

Sun Shuxiang; Jin Wei; Luo Qian; Sheng Ping; Huang Rongmin

1993-01-01

More than 1600 accessions of rice mutant germplasm have been collected since 1980, and 1142 accessions of mutants have been identified according to their agronomy and pattern characters. A part of mutants were compared with their original cultivars in eight main agronomic characters. The results showed that the agronomic characters of mutants induced by ionizing radiations changed to both positive and negative directions compared with their original cultivars. Only 6.3% mutants varied in single agronomic character, and 91.1% mutants varied in two to six agronomic characters. Tenetic analysis and Cellular observations were carried out for two kinds of early mutants. It showed that early mutants 'Yuan Feng Zao' are controlled by two independent and incomplete dominant genes. For the dwarf, the reduction of the number of longitudinal cell layers causes the stem shorter and the increase of the number of horizontal cell layers causes the stem wall thicker. More than 100 preserved accessions of mutants were supplied to breeding units as parents or for genetic studies. Sixteen cultivars (lines) were bred from the parents which played an important role in raising the output of rice production

Growth, Metabolism and Yield of Rice Cultivated in Soils Amended with Fly Ash and Cyanobacteria and Metal Loads in Plant Parts

OpenAIRE

Rabindra N. Padhy; Nabakishore Nayak; Rajesh R. Dash-Mohini; Shakti Rath; Rajani K. Sahu

2016-01-01

Soil amendment with fly ash (FA) and combined supplementation with N2-fixing cyanobacteria masses as biofertilizer were done in field experiments with rice. Amendments with FA levels, 0, 0.5, 1.0, 2.0, 4.0, 8.0 and 10.0 kg/m2, caused increase in growth and yield of rice up to 8.0 kg/m2, monitored with several parameters. Pigment contents and enzyme activities of leaves were enhanced by FA, with the maximum level of FA at 10.0 kg/m2. Protein content of rice seeds was the highest in plants grow...

Whole-plant dynamic system of nitrogen use for vegetative growth and grain filling in rice plants (Oryza sativa L. as revealed through the production of 350 grains from a germinated seed over 150 days: a review and synthesis

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Tadakatsu Yoneyama

2016-08-01

Full Text Available A single germinated rice (Oryza sativa L seed can produce 350 grains with the sequential development of 15 leaves on the main stem and 7 ‒ 10 leaves on 4 productive tillers (forming 5 panicles in total, using nitrogen (N taken up from the environment over a 150-day growing season. Nitrogen travels from uptake sites to the grain through growing organ-directed cycling among sequentially developed organs. Over the past 40 years, the dynamic system for N allocation during vegetative growth and grain filling has been elucidated through studies on N and 15N transport as well as enzymes and transporters involved. In this review, we synthesize the information obtained in these studies along the following main points: (1 During vegetative growth before grain-filling, about half of the total N in the growing organs, including young leaves, tillers, root tips and differentiating panicles is supplied via phloem from mature source organs such as leaves and roots, after turnover and remobilization of proteins, whereas the other half is newly taken up and supplied via xylem, with an efficient xylem-to-phloem transfer at stem nodes. Thus, the growth of new organs depends equally on both N sources. (2 A large fraction (as much as 80% of the grain N is derived largely from mature organs such as leaves and stems by degradation, including the autophagy pathway of chloroplast proteins (e.g., Rubisco. (3 Mobilized proteinogenic amino acids, including arginine, lysine, proline and valine, are derived mainly from protein degradation, with amino acid transporters playing a role in transferring these amino acids across cell membranes of source and sink organs, and enabling their efficient reutilization in the latter. On the other hand, amino acids such as glutamine, glutamic acid, γ-amino butyric acid, aspartic acid, and alanine are produced by assimilation of newly taken up N by roots and transported via xylem and phloem. The formation of 350 filled grains over 50

Mechanism study of sulfur fertilization mediating copper translocation and biotransformation in rice (Oryza sativa L.) plants.

Science.gov (United States)

Sun, Lijuan; Yang, Jianjun; Fang, Huaxiang; Xu, Chen; Peng, Cheng; Huang, Haomin; Lu, Lingli; Duan, Dechao; Zhang, Xiangzhi; Shi, Jiyan

2017-07-01

Metabolism of sulfur (S) is suggested to be an important factor for the homeostasis and detoxification of Cu in plants. We investigated the effects of S fertilizers (S 0 , Na 2 SO 4 ) on Cu translocation and biotransformation in rice plants by using multiple synchrotron-based techniques. Fertilization of S increased the biomass and yield of rice plants, as well as the translocation factor of Cu from root to shoot and shoot to grain, resulting in enhanced Cu in grain. Sulfur K-edge X-ray near edge structure (XANES) analysis showed that fertilization of S increased the concentration of glutathione in different rice tissues, especially in rice stem and leaf. Copper K-edge XANES results indicated that a much higher proportion of Cu (I) species existed in rice grain than husk and leaf, which was further confirmed by soft X-ray scanning transmission microscopy results. Sulfur increased the proportion of Cu (I) species in rice grain, husk and leaf, suggesting the inducing of Cu (II) reduction in rice tissues by S fertilization. These results suggested that fertilization of S in paddy soils increased the accumulation of Cu in rice grain, possibly due to the reduction of Cu (II) to Cu (I) by enhancing glutathione synthesis and increasing the translocation of Cu from shoot to grain. Copyright © 2017 Elsevier Ltd. All rights reserved.

Infection and colonization of rice seedlings by the plant growth-promoting bacterium Herbaspirillum seropedicae Z67.

Science.gov (United States)

James, Euan K; Gyaneshwar, Prasad; Mathan, Natarajan; Barraquio, Wilfredo L; Reddy, Pallavolu M; Iannetta, Pietro P M; Olivares, Fabio L; Ladha, Jagdish K

2002-09-01

A beta-glucoronidase (GUS)-marked strain of Herbaspirillum seropedicae Z67 was inoculated onto rice seedling cvs. IR42 and IR72. Internal populations peaked at over 10(6) log CFU per gram of fresh weight by 5 to 7 days after inoculation (DAI) but declined to 10(3) to 10(4) log CFU per gram of fresh weight by 28 DAI. GUS staining was most intense on coleoptiles, lateral roots, and at the junctions of some of the main and lateral roots. Bacteria entered the roots via cracks at the points of lateral root emergence, with cv. IR72 appearing to be more aggressively infected than cv. IR42. H. seropedicae subsequently colonized the root intercellular spaces, aerenchyma, and cortical cells, with a few penetrating the stele to enter the vascular tissue. Xylem vessels in leaves and stems were extensively colonized at 2 DAI but, in later harvests (7 and 13 DAI), a host defense reaction was often observed. Dense colonies of H. seropedicae with some bacteria expressing nitrogenase Fe-protein were seen within leaf and stem epidermal cells, intercellular spaces, and substomatal cavities up until 28 DAI. Epiphytic bacteria were also seen. Both varieties showed nitrogenase activity but only with added C, and the dry weights of the inoculated plants were significantly increased. Only cv. IR42 showed a significant (approximately 30%) increase in N content above that of the uninoculated controls, and it also incorporated a significant amount of 15N2.

Influence of ethyl-trinexapac on 15N accumulation and distribution and on highland rice yield

International Nuclear Information System (INIS)

Alvarez, Rita de Cassia Felix; Crusciol, Carlos Alexandre Costa; Alvarez, Angela Cristina Camarim; Trivelin, Paulo Cesar Ocheuze; Rodrigues, Joao Domingos

2007-01-01

The high rice grain yields ensured by sprinkler irrigation have encouraged the use of higher fertilizer doses, mainly the nitrogen fertilizers. However, an improper management of nitrogen fertilization may result in plant lodging. Application of plant regulators may redirect assimilates to grain production while limiting the vegetative growth. This study aimed to: evaluate the influence of the growth regulator Ethyl-trinexapac on plant growth parameters and on 15 N accumulation and distribution in the whole plant and plant components, and determine the contribution of nitrogen taken up in different developmental stages in panicle formation, yield components and rice yield. The experiment was carried out under controlled greenhouse conditions. The treatments consisted of application or not of a plant growth regulator (0 and 200 g active ingredient ha-1 of ethyl-trinexapac) at four plant development stages (beginning to end of tillering; end of tillering and flower differentiation; flower differentiation to flowering; flowering until physiological maturation). The experimental design was arranged in random blocks, in a 2 x 4 factorial scheme, with three replications. The plants were placed in a group of 48 pots. In a group of 24 pots with nutrient solution containing 15 NH 4 SO 4 , plants were collected and separated in parts in the beginning of each pre-established plant development stage and at the end of each stage. In a second group (24 pots), pre-labeled plants were left to grow in nutrient solution with 14 NH 4 SO 4 and harvested at the end of each cycle in order to access 15 N redistribution.. The growth regulator reduced plant height and 15 N accumulation in the panicle and promoted redistribution of the absorbed 15 N, and increased accumulated 15 N in root, stem+sheats and leaves. The contribution of absorbed 15 N to panicle formation in each stage increased with the plant development, though in a lower proportion in the presence of the growth regulator

Pathways in STEM: Factors affecting the retention and attrition of talented men and women from the STEM pipeline

Science.gov (United States)

Heilbronner, Nancy N.

Many men and women who are talented in science, technology, engineering, and/or mathematics (STEM) choose not to pursue undergraduate majors or careers in these fields. To develop talents in STEM, educators must understand the factors that contribute to an individual's retention in STEM domains, as well as the factors that act as barriers to success, such as the role that gender plays in the underrepresentation of women in certain STEM fields (e.g., computer science and engineering) and changes in recent decades in the process of selecting STEM majors and careers. The purpose of this study was to explore the influences that guide decisions related to the selection of majors and occupations during high school, post-secondary education, and early careers. Survey methodology was used to explore the perceptions of 360 Science Talent Search (STS) semifinalists and finalists during the years 1987-1989 and 1997-1999, and quantitative procedures were used to analyze the data. A majority (74.2%) of STS participants majored in a STEM field in college, and most (68.6%) currently work in a STEM field. A greater percentage of men selected computer science, engineering, physics, and mathematics majors, and a greater percentage of women selected biological science and chemistry. Belief in one's ability to achieve in STEM was a predictor of STEM majors in college and STEM concentrations in graduate school, but differences were found between men's and women's self-efficacy in STEM during high school and in college, as women had lower self-efficacy. Sex was a predictor of STEM majors in college, but perceived quality of academic courses was not. STEM majors also reported more satisfaction with their STEM courses in high school and college than non-STEM majors. In a departure from the results of previous research, the reasons that men and women selected occupations were similar, as were the reasons they chose to leave or not to enter STEM. The most frequently cited reason for

Autophagy Supports Biomass Production and Nitrogen Use Efficiency at the Vegetative Stage in Rice1[OPEN

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Hayashida, Yasukazu; Kurusu, Takamitsu; Kojima, Soichi; Makino, Amane

2015-01-01

Much of the nitrogen in leaves is distributed to chloroplasts, mainly in photosynthetic proteins. During leaf senescence, chloroplastic proteins, including Rubisco, are rapidly degraded, and the released nitrogen is remobilized and reused in newly developing tissues. Autophagy facilitates the degradation of intracellular components for nutrient recycling in all eukaryotes, and recent studies have revealed critical roles for autophagy in Rubisco degradation and nitrogen remobilization into seeds in Arabidopsis (Arabidopsis thaliana). Here, we examined the function of autophagy in vegetative growth and nitrogen usage in a cereal plant, rice (Oryza sativa). An autophagy-disrupted rice mutant, Osatg7-1, showed reduced biomass production and nitrogen use efficiency compared with the wild type. While Osatg7-1 showed early visible leaf senescence, the nitrogen concentration remained high in the senescent leaves. 15N pulse chase analysis revealed suppression of nitrogen remobilization during leaf senescence in Osatg7-1. Accordingly, the reduction of nitrogen available for newly developing tissues in Osatg7-1 likely led its reduced leaf area and tillers. The limited leaf growth in Osatg7-1 decreased the photosynthetic capacity of the plant. Much of the nitrogen remaining in senescent leaves of Osatg7-1 was in soluble proteins, and the Rubisco concentration in senescing leaves of Osatg7-1 was about 2.5 times higher than in the wild type. Transmission electron micrographs showed a cytosolic fraction rich with organelles in senescent leaves of Osatg7-1. Our results suggest that autophagy contributes to efficient nitrogen remobilization at the whole-plant level by facilitating protein degradation for nitrogen recycling in senescent leaves. PMID:25786829

Antioxidant activity and phenol content of extracts of bark, stems, and young and mature leaves from Blepharocalyx salicifolius (Kunth O. Berg

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E. Habermann

Full Text Available Abstract Phenolic compounds are a group of plant secondary metabolites known to have a variety of bioactivities, including the ability to function as antioxidants. Because of the side effects of the use of synthetic substances, the search for natural and less toxic compounds has increased significantly. This study was designed to evaluate the antioxidant activity and phenol content of hexane, ethyl acetate, and aqueous extracts of the bark (suber and stems as well as the young and mature leaves of Blepharocalyx salicifolius. The extracts were obtained by extraction with organic solvents and subsequent fractionation by chromatographic partition coefficient. Preliminary tests for the presence of antioxidants were performed using bioautography in thin-layer chromatography. The antioxidant activity of the extracts was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH method, and the phenol content of the extracts was quantified using the Folin-Ciocalteu technique. The results showed that 9 of the 12 extracts evaluated displayed very strong antioxidant activity and three displayed moderate activity. Aqueous extracts of the young leaves and bark and the ethyl acetate extract of the young leaves showed the highest levels of antioxidant activity and total phenolic content (TPC. A correlation was observed between TPC and antioxidant activity index (AAI with a correlation coefficient (r2 of 0.7999. Thus, the high phenol content of B. salicifolius extracts and its correlation with antioxidant activity provide substrates for further studies.

Effects of water management practices on residue decomposition and degradation of Cry1Ac protein from crop-wild Bt rice hybrids and parental lines during winter fallow season.

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Xiao, Manqiu; Dong, Shanshan; Li, Zhaolei; Tang, Xu; Chen, Yi; Yang, Shengmao; Wu, Chunyan; Ouyang, Dongxin; Fang, Changming; Song, Zhiping

2015-12-01

Rice is the staple diet of over half of the world's population and Bacillus thuringiensis (Bt) rice expressing insecticidal Cry proteins is ready for deployment. An assessment of the potential impact of Bt rice on the soil ecosystem under varied field management practices is urgently required. We used litter bags to assess the residue (leaves, stems and roots) decomposition dynamics of two transgenic rice lines (Kefeng6 and Kefeng8) containing stacked genes from Bt and sck (a modified CpTI gene encoding a cowpea trypsin inhibitor) (Bt/CpTI), a non-transgenic rice near-isoline (Minghui86), wild rice (Oryza rufipogon) and crop-wild Bt rice hybrid under contrasting conditions (drainage or continuous flooding) in the field. No significant difference was detected in the remaining mass, total C and total N among cultivars under aerobic conditions, whereas significant differences in the remaining mass and total C were detected between Kefeng6 and Kefeng8 and Minghui86 under the flooded condition. A higher decomposition rate constant (km) was measured under the flooded condition compared with the aerobic condition for leaf residues, whereas the reverse was observed for root residues. The enzyme-linked immunosorbent assay (ELISA), which was used to monitor the changes in the Cry1Ac protein in Bt rice residues, indicated that (1) the degradation of the Cry1Ac protein under both conditions best fit first-order kinetics, and the predicted DT50 (50% degradation time) of the Cry1Ac protein ranged from 3.6 to 32.5 days; (2) the Cry1Ac protein in the residue degraded relatively faster under aerobic conditions; and (3) by the end of the study (~154 days), the protein was present at a low concentration in the remaining residues under both conditions. The degradation rate constant was negatively correlated with the initial carbon content and positively correlated with the initial Cry1Ac protein concentration, but it was only correlated with the mass decomposition rate constants under

Toxicological evaluation of methanol leaves extract of Vernonia ...

African Journals Online (AJOL)

of hepatocytes, peripheral cramped chromatin, shrinkages (single cell death) of hepatocytes, fragmentation of hepatocytes while no histopathological changes were ... of the stem- bark, the roots, and the leaves of V. amyg- dalina are also reported to be ... Mice of the same sex were grouped into. 8 experimental and 1 control ...

Effect of microwave energy on grain quality of four Spanish rice varieties

International Nuclear Information System (INIS)

Osca, J.M.; Marzal, A.; Castell, V.; Martínez, J.; Benedito, C.; Balbastre, J.V.; Sánchez-Hernández, D.

2005-01-01

A microwave system can be used as an alternative method to methyl bromide to control rice storage pests. Four rice varieties (Oryza sativa L.) grown in Spain (‘Bomba’, ‘Senia’, ‘Puntal’ and ‘Thainato’) were irradiated with three levels of microwave energy (0, 70 and 100 J g –1 ). Rice quality attributes were analysed to establish hypothetical quality changes in order to use microwave energy as an alternative method to control pests. Results of the factorial analysis showed that the analysed attributes differed more within varieties than among microwave treatments of the varieties, except for ‘Thainato’ which, after applying microwave energy of 100 J g –1 , presented a different adhesiveness from the other two treatments determined by factor 1 and ‘Puntal’ treated with microwaves presented a different water uptake and loss of solids in cooking water determined by factor 3 than the control. The increase in hardness and decrease in adhesiveness as a consequence of the microwave treatment could possibly damage rice quality. This aspect must be taken into account with this method. In conclusion, microwave energy can be used as an alternative method of insect control because it does not seriously affect rice quality. Microwave treatments did not leave undesirable residues and could be as effective at controlling insect infestation as any procedure currently available. (author) [es

Effect of Various Types of Herbs on Sensory Properties and Blood Glucosa Response Adan Instant Black Rice

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Bernatal Saragih

2013-06-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE Management based on the carbohydrate diet is very important to do and not to be avoided but how diet and variations of carbohydrate consumed is set mainly the source of rice that does not fast respond to an increase in blood glucose. Therefore, Evaluation of nutritional and instant rice production that is the functional food and have a low glycemic index rice sourced locally as the East Kalimantan native rice black Adan will be very beneficial for health. The aim of this research was to evaluate of the nutritional and effect of various herbal on sensory properties and blood glucose response Adan instant black rice. Adan black rice has a protein content of 8.10%, Fe 3.61 mg/1000g and 3.33 g/100g total dietary fiber and includes a group of rice with low amylose. Organoleptic value of instant rice black Adan produced the most preferred by panellists also from the addition of ginger extract and pandan leaves , water, onion tiwai, tea and last turmeric. The digestibility of starch decreased 19.04 (mg/1000g after being a functional of instant rice black Adan. Difference in reduction of blood glucose levels in volunteers who consumed black Adan instant rice by 14.20 mg/dL, whereas the provision of a reference food (glucose of 71.50 mg/dL, this indicates of instant rice functional black Adan provide availability of glucose in the blood longer available.

Comparative management of Chilo suppressalis (Walker) (Lepidoptera: Crambidae) by convenient pesticides and non-chemical practices in a double rice cropping system

OpenAIRE

M. N. Poor Amiri; Faramarz Alinia; Sohrab Imani, et al.

2017-01-01

The inclination of rice growers towards double cropping system in north of Iran has raised new concerns about the excessive release of broad-spectrum pesticides, particularly organophosphates, in the environment. In this study, the efficiency of three insecticides and an integrated pest management (IPM) program for management of the striped rice stem borer, Chilo suppressalis (Walker) (Lep: Crambidae), in double cropping system was investigated under field condition. According to the results,...

Physiological Age Status of Female Adults and Off-Season Survival of Rice Leaffolder Cnaphalocrocis medinalis in India

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Padmavathi Chintalapati

2015-09-01

Full Text Available Rice leaffolder, Cnaphalocrocis medinalis, is one of the major foliage feeders found in the rice growing regions in India. When the crop was at maturity, numerous adults of rice leaffolder were found in the rice fields though the larval population gradually decreased, and no eggs were found on rice leaves. The population characteristics of C. medinalis were assessed based on the physiological age status of adults at different crop growth stages. Based on egg development within ovarioles, ovariole appearance, number and colour of fat bodies, and characteristics of bursa copulatrix, physiological age status of the adults was described, which served as a basis for the determination of age composition. C. medinalis adults were found during the first week of August on rice plants, of which 44% were in Age 0 with immature ovaries, indicating immigrants. However, 28% adults each were at Ages 1–2 with developing ovaries, indicating local breeding population. The carryover and off-season survival of C. medinalis were also studied to determine the contribution of the alternative hosts in the population growth that helped in devising efficient management strategies. Rice was the most preferred host followed by Triticum aestivum, Echinochloa crusgulli and Brachiaria plantaginea. Various routes of the carryover of C. medinalis from season to season were discussed.

Effect of microcystins on root growth, oxidative response, and exudation of rice (Oryza sativa).

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Cao, Qing; Rediske, Richard R; Yao, Lei; Xie, Liqiang

2018-03-01

A 30 days indoor hydroponic experiment was carried out to evaluate the effect of microcystins (MCs) on rice root morphology and exudation, as well as bioaccumulation of MCs in rice. MCs were bioaccumulated in rice with the greatest concentrations being observed in the leaves (113.68μgg -1 Fresh weight (FW)) when exposed to 500μgL -1 MCs. Root activity at 500μgL -1 decreased 37%, compared to the control. MCs also induced disruption of the antioxidant system and lipid peroxidation in rice roots. Root growth was significantly inhibited by MCs. Root weight, length; surface area and volume were significantly decreased, as well as crown root number and lateral root number. After 30 days exposure to MCs, an increase was found in tartaric acid and malic acid while the other organic acids were not affected. Glycine, tyrosine, and glutamate were the only amino acids stimulated at MCs concentrations of 500μgL -1 . Similarly, dissolved organic carbon (DOC) and carbohydrate at 50 and 500μgL -1 treatments were significantly increased. The increase of DOC and carbohydrate in root exudates was due to rice root membrane permeability changes induced by MCs. Overall, this study indicated that MCs significantly inhibited rice root growth and affected root exudation. Copyright © 2017 Elsevier Inc. All rights reserved.

Lower responsiveness of canopy evapotranspiration rate than of leaf stomatal conductance to open-air CO2 elevation in rice.

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Shimono, Hiroyuki; Nakamura, Hirofumi; Hasegawa, Toshihiro; Okada, Masumi

2013-08-01

An elevated atmospheric CO2 concentration ([CO2 ]) can reduce stomatal conductance of leaves for most plant species, including rice (Oryza sativa L.). However, few studies have quantified seasonal changes in the effects of elevated [CO2 ] on canopy evapotranspiration, which integrates the response of stomatal conductance of individual leaves with other responses, such as leaf area expansion, changes in leaf surface temperature, and changes in developmental stages, in field conditions. We conducted a field experiment to measure seasonal changes in stomatal conductance of the uppermost leaves and in the evapotranspiration, transpiration, and evaporation rates using a lysimeter method. The study was conducted for flooded rice under open-air CO2 elevation. Stomatal conductance decreased by 27% under elevated [CO2 ], averaged throughout the growing season, and evapotranspiration decreased by an average of 5% during the same period. The decrease in daily evapotranspiration caused by elevated [CO2 ] was more significantly correlated with air temperature and leaf area index (LAI) rather than with other parameters of solar radiation, days after transplanting, vapor-pressure deficit and FAO reference evapotranspiration. This indicates that higher air temperatures, within the range from 16 to 27 °C, and a larger LAI, within the range from 0 to 4 m(2)  m(-2) , can increase the magnitude of the decrease in evapotranspiration rate caused by elevated [CO2 ]. The crop coefficient (i.e. the evapotranspiration rate divided by the FAO reference evapotranspiration rate) was 1.24 at ambient [CO2 ] and 1.17 at elevated [CO2 ]. This study provides the first direct measurement of the effects of elevated [CO2 ] on rice canopy evapotranspiration under open-air conditions using the lysimeter method, and the results will improve future predictions of water use in rice fields. © 2013 John Wiley & Sons Ltd.

Quantificação de ácido alfa-linolênico em caules e folhas de linho (Linum usitatissimum L. colhidos em diferentes estágios de desenvolvimento Quantification of alpha-linolenic acid in stems and leaves of flax (Linum usitatissimum L. harvested in different stages of development

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Ana Carolina de Aguiar

2010-12-01

Full Text Available O objetivo deste estudo foi quantificar o ácido alfa-linolênico [LNA, 18:3 (n-3], avaliar a composição centesimal das folhas e caules de linho (Linum usitatissimum L. submetidos à secagem e colhidos em diferentes estágios de desenvolvimento (40, 80 e 120 dias, e determinar o potencial antioxidante das folhas colhidas aos 80 dias através do teste com o radical DPPH. As folhas obtiveram maiores teores de cinzas, proteína e lipídios totais em relação aos caules. Tanto as folhas quanto os caules apresentaram razões de AGPI/AGS e n-6/n-3 dentro dos valores considerados adequados para a alimentação. Os caules colhidos nos diferentes tempos não apresentaram diferenças significativas (PThe objective of this study was to quantify the alpha-linolenic acid [LNA, 18:3 (n-3] and to evaluate the proximate composition of leaves and stems of flax (Linum usitatissimum L. dried and harvested at different stages of development (40, 80 and 120 days, and to determine the antioxidant potential of the leaf harvested at 80 days using the test of DPPH radical. The leaves had higher levels of ash, protein and total lipids when compared to the stems. Both the leaves as the stems had ratios of PUFA/SFA and n-6/n-3 within the values considered suitable for food. Stems in the different stages showed no significant difference (P<0.05 of LNA content. Leaves harvested at 80 days showed the highest concentration of LNA, corresponding to 1,262.36 mg/100g dried leaf. The different extracts (methanol, butanol, acetate and water were efficient in the inhibition of DPPH radical, with emphasis on the butanolic and acetate fractions and the values of IC50 were approximately 42 ppm. These results highlight the nutritional potential and antioxidant activity of leaves and stems of flaxseed for future use in the animal and human feeding.

Lodging Resistance of Japonica Rice (Oryza Sativa L.): Morphological and Anatomical Traits due to top-Dressing Nitrogen Application Rates.

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Zhang, Wujun; Wu, Longmei; Wu, Xiaoran; Ding, Yanfeng; Li, Ganghua; Li, Jingyong; Weng, Fei; Liu, Zhenghui; Tang, She; Ding, Chengqiang; Wang, Shaohua

2016-12-01

Lodging in rice production often limits grain yield and quality by breaking or bending stems. Excessive nitrogen (N) fertilizer rates are the cause of poor lodging resistance in rice, but little is known about the effect of top-dressing N application rates on the mechanical strength of japonica rice plants, especially how the anatomical structure in culms is affected by N. In this study, field experiments on two japonica rice varieties with three top-dressing N application rates, 0 kg N ha(-1) (LN), 135 kg N ha(-1) (MN), and 270 kg N ha(-1) (HN) as urea, were conducted. Wuyunjing23, a lodging-resistant japonica rice cultivar and W3668, a lodging-susceptible japonica rice cultivar were used. The lodging index, breaking strength, morphological and anatomical traits in culms were measured in this study. The visual lodging rate in japonica rice differed remarkably between genotypes and top-dressing N treatments. The higher lodging index of rice plants was primarily attributed to the weak breaking strength of the lower internodes. The longer elongated basal internodes were responsible for higher plant height and a higher lodging index. Correlation analysis showed that breaking strength was significantly and positively correlated with the thickness of the mechanical tissue but was significantly and negatively correlated with the inner diameter of the major axis (b2). With increasing top-dressing N rates, the sclerenchyma cells of the mechanical tissues and the vascular bundles of the Wuyunjing23 cultivar varied little. The plant height, inner diameter of the minor axis (a2) and b2 increased significantly, but the area of the large vascular bundle (ALVB) and the area of the small vascular bundle (ASVB) decreased significantly and resulted in lower stem strength and a higher lodging index under higher top-dressing N conditions. The culm diameter of the W3668 cultivar increased slightly with no significant difference, and the sclerenchyma cells in the mechanical

Broken rice kernels and the kinetics of rice hydration and texture during cooking.

Science.gov (United States)

Saleh, Mohammed; Meullenet, Jean-Francois

2013-05-01

During rice milling and processing, broken kernels are inevitably present, although to date it has been unclear as to how the presence of broken kernels affects rice hydration and cooked rice texture. Therefore, this work intended to study the effect of broken kernels in a rice sample on rice hydration and texture during cooking. Two medium-grain and two long-grain rice cultivars were harvested, dried and milled, and the broken kernels were separated from unbroken kernels. Broken rice kernels were subsequently combined with unbroken rice kernels forming treatments of 0, 40, 150, 350 or 1000 g kg(-1) broken kernels ratio. Rice samples were then cooked and the moisture content of the cooked rice, the moisture uptake rate, and rice hardness and stickiness were measured. As the amount of broken rice kernels increased, rice sample texture became increasingly softer (P hardness was negatively correlated to the percentage of broken kernels in rice samples. Differences in the proportions of broken rice in a milled rice sample play a major role in determining the texture properties of cooked rice. Variations in the moisture migration kinetics between broken and unbroken kernels caused faster hydration of the cores of broken rice kernels, with greater starch leach-out during cooking affecting the texture of the cooked rice. The texture of cooked rice can be controlled, to some extent, by varying the proportion of broken kernels in milled rice. © 2012 Society of Chemical Industry.

Effects of phyllotaxy on biomechanical properties of stems of Cercis occidentalis (Fabaceae).

Science.gov (United States)

Caringella, Marissa A; Bergman, Brett A; Stanfield, Ryan C; Ewers, Madeleine M; Bobich, Edward G; Ewers, Frank W

2014-01-01

Phyllotaxy, the arrangement of leaves on a stem, may impact the mechanical properties of woody stems several years after the leaves have been shed. We explored mechanical properties of a plant with alternate distichous phyllotaxy, with a row of leaves produced on each side of the stem, to determine whether the nodes behave as spring-like joints. Flexural stiffness of 1 cm diameter woody stems was measured in four directions with an Instron mechanical testing system; the xylem of the stems was then cut into node (former leaf junction) and nonnode segments for measurement of xylem density. Stems had 20% greater flexural stiffness in the plane perpendicular to the original leaf placement than in the parallel plane. The xylem in the node region was more flexible, but it had significantly greater tissue density than adjacent regions, contradicting the usual correlation between wood density and stiffness. Nodes can behave as spring-like joints in woody plants. For plagiotropic shoots, distichous phyllotaxy results in stems that resist up-and-down bending more than lateral back-and-forth movement. Thus, they may more effectively absorb applied loads from fruits, animals, wind, rain, and snow and resist stresses due to gravity without cracking and breaking. Under windy conditions, nodes may improve damping by absorbing vibrational energy and thus reducing oscillation damage. The effect of plant nodes also has biomimetic design implications for architects and material engineers.

Investigating differences in light stable isotopes between Thai jasmine rice and Sungyod rice

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Kukusamude, C.; Kongsri, S.

2017-10-01

We report the differences in light stable isotopes between two kinds of Thai rice (Thai jasmine and Sungyod rice). Thai jasmine rice and Sungyod rice were cultivated in the northeast and the south of Thailand. Light isotopes including 13C, 15N and 18O of Thai jasmine rice and Sungyod rice samples were carried out using isotope ratio mass spectrometry (IRMS). Thai jasmine rice (Khao Dawk Mali 105) was cultivated from Thung Kula Rong Hai area, whereas Sungyod rice was cultivated from Phathalung province. Hypothesis testing of difference of each isotope between Thai jasmine rice and Sungyod rice was also studied. The study was the feasibility test whether the light stable isotopes can be the variables to identify Thai jasmine rice and Sungyod rice. The result shows that there was difference in the isotope patterns of Thai jasmine rice and Sungyod rice. Our results may provide the useful information in term of stable isotope profiles of Thai rice.

Intercellular production of tamavidin 1, a biotin-binding protein from Tamogitake mushroom, confers resistance to the blast fungus Magnaporthe oryzae in transgenic rice.

Science.gov (United States)

Takakura, Yoshimitsu; Oka, Naomi; Suzuki, Junko; Tsukamoto, Hiroshi; Ishida, Yuji

2012-05-01

The blast fungus Magnaporthe oryzae, one of the most devastating rice pathogens in the world, shows biotin-dependent growth. We have developed a strategy for creating disease resistance to M. oryzae whereby intercellular production of tamavidin 1, a biotin-binding protein from Pleurotus cornucopiae occurs in transgenic rice plants. The gene that encodes tamavidin 1, fused to the sequence for a secretion signal peptide derived from rice chitinase gene, was connected to the Cauliflower mosaic virus 35S promoter, and the resultant construct was introduced into rice. The tamavidin 1 was accumulated at levels of 0.1-0.2% of total soluble leaf proteins in the transgenic rice and it was localized in the intercellular space of rice leaves. The tamavidin 1 purified from the transgenic rice was active, it bound to biotin and inhibited in vitro growth of M. oryzae by causing biotin deficiency. The transgenic rice plants showed a significant resistance to M. oryzae. This study shows the possibility of a new strategy to engineer disease resistance in higher plants by taking advantage of a pathogen's auxotrophy.

Women in STEM hit by discrimination

Science.gov (United States)

Randall, Ian

2016-02-01

Almost a third of women in science, technology, engineering and mathematics (STEM) in Australia are considering leaving their job within the next five years, according to a survey by the employee association Professionals Australia.

Screen of Bacillus thuringiensis toxins for transgenic rice to control Sesamia inferens and Chilo suppressalis.

Science.gov (United States)

Gao, Yulin; Hu, Yang; Fu, Qiang; Zhang, Jie; Oppert, Brenda; Lai, Fengxiang; Peng, Yufa; Zhang, Zhitao

2010-09-01

Transgenic rice to control stem borer damage is under development in China. To assess the potential of Bacillus thuringiensis (Bt) transgenes in stem borer control, the toxicity of five Bt protoxins (Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ba and Cry1Ca) against two rice stem borers, Sesamia inferens (pink stem borer) and Chilo suppressalis (striped stem borer), was evaluated in the laboratory by feeding neonate larvae on artificial diets containing Bt protoxins. The results indicated that Cry1Ca exhibited the highest level of toxicity to both stem borers, with an LC(50) of 0.24 and 0.30 microg/g for C. suppressalis and S. inferens, respectively. However, S. inferens was 4-fold lower in susceptibility to Cry1Aa, and 6- and 47-fold less susceptible to Cry1Ab and Cry1Ba, respectively, compared to C. suppressalis. To evaluate interactions among Bt protoxins in stem borer larvae, toxicity assays were performed with mixtures of Cry1Aa/Cry1Ab, Cry1Aa/Cry1Ca, Cry1Ac/Cry1Ca, Cry1Ac/Cry1Ba, Cry1Ab/Cry1Ac, Cry1Ab/Cry1Ba, and Cry1Ab/Cry1Ca at 1:1 (w/w) ratios. All protoxin mixtures demonstrated significant synergistic toxicity activity against C. suppressalis, with values of 1.6- to 11-fold higher toxicity than the theoretical additive effect. Surprisingly, all but one of the Bt protoxin mixtures were antagonistic in toxicity to S. inferens. In mortality-time response experiments, S. inferens demonstrated increased tolerance to Cry1Ab and Cry1Ac compared to C. suppressalis when treated with low or high protoxin concentrations. The data indicate the utility of Cry1Ca protoxin and a Cry1Ac/Cry1Ca mixture to control both stem borer populations. Copyright 2010 Elsevier Inc. All rights reserved.

MENINGKATKAN PERTUMBUHAN TANAMAN TOMAT (Lycopersicon esculentum DENGAN SISTEM BUDIDAYA HIDROPONIK

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Catur Wasonowati

2011-03-01

Full Text Available Tomato is vegetable that has high economic and nutritional value. Hydroponics is the cultivation of plants without soil but using rice husk charcoal, rockwool, pumice, sand, gravel, perlite water and air media. This research aims to study the effect of nutrients and polybag size on growth and yield of hydroponic tomatoes. The experiment was conducted in Kassa House of Agroekoteknologi Departement Faculty of Agriculture Trunojoyo University. Fertilizers used were Hidrogroup and Greentonik while polybag size are 30x30 cm, 30x40 cm and 40x40 cm. The design of this study using Complete Randomized Design (CRD with 3 replications. The result showed that this research affect to the vegetative phase. No interaction between type of nutrition and polybag size on plant height, leaf number, stem diameter, number of flowers, flowering time of tomato. Type of nutrition significantly affect plant height, leaf number, stem diameter, flower number and wet and dry weight of stems and leaves, whereas the size of polybags significantly affects in the number of leaves, wet and dry weight of stems and leaves of tomato.

Induced mutation for tungro resistance in rice

International Nuclear Information System (INIS)

Ikeda, R.; Yumol, R.R.; Taura, S.

2001-01-01

Tungro is the most serious virus disease of rice in South and Southeast Asia. It is a composite disease of two kinds of viruses, rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV). Damage to the plant is mostly caused by RTBV, while RTSV acts to facilitate RTBV acquisition and transmission by insect vector. Both viruses are transmitted mainly by green leafhopper (GLH). Resistance to GLH is common in rice germplasm but extremely rare for the two viruses. To induce mutations for tungro resistance, a susceptible variety IR22 was treated with N-methyl-N-nitrosourea (MNH) following the procedure of Satoh and Omura. The panicles of rice variety 'IR22' were soaked in 1 mM MNH solution for 45 minutes at 16 to 18 hours after flowering. Two thousand six hundred and forty fertile M 1 plants were produced. From these plants M 2 lines with 10 or more seedlings were planted in the field to evaluate their reaction against tungro under natural conditions in the 1990 dry season on the IRRI central research farm, Los Banos, the Philippines. Of these, 124 M 2 lines were selected by visual evaluation. Five plants were harvested individually from each selected line. A bulk was also made from all the remaining plants in the line. In the M 3 generation, each family consisted of five sister lines and one bulked line. One line (M 3 -723) showed no tungro symptoms and its related bulk segregated for resistance but all other M 3 lines from the same family were susceptible to tungro. The resistant line, M 3 -723, showed low infection with RTBV and RTSV when leaves were tested by enzyme-linked immunosorbent assay (ELISA) to diagnose tungro infection. All M 4 lines from M 3 -723 showed uniform resistance in the field. They were not infected with RTBV and were resistant to RTSV infection

Extraction of rice bran oil from local rice husk

International Nuclear Information System (INIS)

Anwar, J.; Zaman, W.; Salman, M.; Jabeen, N.

2006-01-01

Rice Bran Oil is widely used in pharmaceutical, food and chemical industries due to its unique properties and high medicinal value. In the present work, extraction of rice bran oil from different samples of rice husk collected from local rice shellers by solvent extraction method has been studied. Experiments were conducted using a soxhelt apparatus, to extract rice bran oil using hexane, petroleum ether, ethanol and methanol as the solvents and the yields obtained under different conditions were compared. Batch extraction tests showed that the rate of extraction decreases with time and the solution approaches saturation at an exponential rate. (author)

Comparative Study of the Detection of Chromium Content in Rice Leaves by 532 nm and 1064 nm Laser-Induced Breakdown Spectroscopy

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Jiyu Peng

2018-02-01

Full Text Available Fast detection of toxic metals in crops is important for monitoring pollution and ensuring food safety. In this study, laser-induced breakdown spectroscopy (LIBS was used to detect the chromium content in rice leaves. We investigated the influence of laser wavelength (532 nm and 1064 nm excitation, along with the variations of delay time, pulse energy, and lens-to-sample distance (LTSD, on the signal (sensitivity and stability and plasma features (temperature and electron density. With the optimized experimental parameters, univariate analysis was used for quantifying the chromium content, and several preprocessing methods (including background normalization, area normalization, multiplicative scatter correction (MSC transformation and standardized normal variate (SNV transformation were used to further improve the analytical performance. The results indicated that 532 nm excitation showed better sensitivity than 1064 nm excitation, with a detection limit around two times lower. However, the prediction accuracy for both excitation wavelengths was similar. The best result, with a correlation coefficient of 0.9849, root-mean-square error of 3.89 mg/kg and detection limit of 2.72 mg/kg, was obtained using the SNV transformed signal (Cr I 425.43 nm induced by 532 nm excitation. The results indicate the inspiring capability of LIBS for toxic metals detection in plant materials.

Match sources of manure in corrective land rice high in first year of culture

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Anderson Lange

2016-08-01

Full Text Available The objective was to evaluate the effect of phosphorus sources as a partial corrective fertilization and maintenance in upland rice cultivation. The experiment was conducted in the municipality of Alta Floresta/MT in crop year 2007/08, using the experimental design of randomized blocks with five treatments (control, simple superphosphate, triple superphosphate, Arad reactive rock phosphate and bone meal, and four replications. The following characteristics were evaluated: plant height, stem diameter, tiller number per meter, panicle number per m2, Internode length, number of grains per panicle, percentage of filled grains, voids, weight of 100 grains, return on beans, whole grain yield and productivity. Applying phosphorus influenced most of the morphological characteristics of the rice, except the stem diameter and length of the internode. There was influence of phosphate sources for the number of grains per panicle and productivity and that the two variables for the treatments with superphosphate and triple superphosphate were higher than the control. The use of triple superphosphate provided greater productivity and higher economic return in the first year of cultivation.

Identification and characterization of dwarf 62, a loss-of-function mutation in DLT/OsGRAS-32 affecting gibberellin metabolism in rice.

Science.gov (United States)

Li, Wenqiang; Wu, Jianguo; Weng, Shili; Zhang, Yujiang; Zhang, Dapeng; Shi, Chunhai

2010-11-01

A dwarf mutant, dwarf 62 (d62), was isolated from rice cultivar 93-11 by mutagenesis with γ-rays. Under normal growth conditions, the mutant had multiple abnormal phenotypes, such as dwarfism, wide and dark-green leaf blades, reduced tiller numbers, late and asynchronous heading, short roots, partial male sterility, etc. Genetic analysis indicated that the abnormal phenotypes were controlled by the recessive mutation of a single nuclear gene. Using molecular markers, the D62 gene was fine mapped in 131-kb region at the short arm of chromosome 6. Positional cloning of D62 gene revealed that it was the same locus as DLT/OsGRAS-32, which encodes a member of the GRAS family. In previous studies, the DLT/OsGRAS-32 is confirmed to play positive roles in brassinosteroid (BR) signaling. Sequence analysis showed that the d62 carried a 2-bp deletion in ORF region of D62 gene which led to a loss-of-function mutation. The function of D62 gene was confirmed by complementation experiment. RT-PCR analysis and promoter activity analysis showed that the D62 gene expressed in all tested tissues including roots, stems, leaves and panicles of rice plant. The d62 mutant exhibited decreased activity of α-amylase in endosperm and reduced content of endogenous GA(1). The expression levels of gibberellin (GA) biosynthetic genes including OsCPS1, OsKS1, OsKO1, OsKAO, OsGA20ox2/SD1 and OsGA2ox3 were significantly increased in d62 mutant. Briefly, these results demonstrated that the D62 (DLT/OsGRAS-32) not only participated in the regulation of BR signaling, but also influenced GA metabolism in rice.

RiceAtlas, a spatial database of global rice calendars and production.

Science.gov (United States)

Laborte, Alice G; Gutierrez, Mary Anne; Balanza, Jane Girly; Saito, Kazuki; Zwart, Sander J; Boschetti, Mirco; Murty, M V R; Villano, Lorena; Aunario, Jorrel Khalil; Reinke, Russell; Koo, Jawoo; Hijmans, Robert J; Nelson, Andrew

2017-05-30

Knowing where, when, and how much rice is planted and harvested is crucial information for understanding the effects of policy, trade, and global and technological change on food security. We developed RiceAtlas, a spatial database on the seasonal distribution of the world's rice production. It consists of data on rice planting and harvesting dates by growing season and estimates of monthly production for all rice-producing countries. Sources used for planting and harvesting dates include global and regional databases, national publications, online reports, and expert knowledge. Monthly production data were estimated based on annual or seasonal production statistics, and planting and harvesting dates. RiceAtlas has 2,725 spatial units. Compared with available global crop calendars, RiceAtlas is nearly ten times more spatially detailed and has nearly seven times more spatial units, with at least two seasons of calendar data, making RiceAtlas the most comprehensive and detailed spatial database on rice calendar and production.

Deferral of leaf senescence and increased productivity in rice

International Nuclear Information System (INIS)

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

1978-01-01

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

Bio-fortification and shelf-life extension of idli batter using curry leaves (Murraya koenigii).

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Chelliah, R; Ramakrishnan, S R; Premkumar, D; Antony, U

2016-06-01

Among several traditional foods of India, idli is one of the most popular and commonly consumed steamed products. A new method of adding Murraya koenigii (curry leaves) to idli batter as a vehicle for fortification and extension of shelf-life has been developed. Dried curry leaves powder was incorporated with other ingredients like rice and dehusked black gram in different proportions to optimize the most palatable formulation. Rate of fermentation and microbial changes in the batter; nutritional qualities, texture and sensory properties of the prepared product were assessed. Incorporation of curry leaves powder (5 %) in idli batter increased the shelf-life and also increased the flavour, texture and appearance of the idli. The calcium content of the prepared idli was 10 times more than that of the control idli, while dietary fiber content increased by 18.6 %. Anti-microbial activity of the curry leaves in idli batter extended the shelf-life from 2 to 5 days when stored at 30 °C.

Roles of xanthophylls and exogenous ABA in protection against NaCl-induced photodamage in rice (Oryza sativa L) and cabbage (Brassica campestris).

Science.gov (United States)

Zhu, Su-Qin; Chen, Ming-Wei; Ji, Ben-Hua; Jiao, De-Mao; Liang, Jian-Sheng

2011-08-01

Changes in actual efficiency of PS II photochemistry, non-photochemical quenching (NPQ), content of xanthophylls and kinetics of de-epoxidation were studied in ABA-fed and non-ABA-fed leaves of rice and cabbage under NaCl stress. Salt stress induced more progressive decrease in actual efficiency of PS II photochemistry (ФPS II), higher reduction state of PS II, and a small significant increase in NPQ in NaCl-sensitive rice plants as compared with NaCl-tolerant cabbage plants, whereas exogenously supplied ABA alleviated the decrease in actual efficiency of PS II photochemistry (ФPS II), induced a lower reduction state of PS II, and caused higher capacity of NPQ in ABA-fed plants than in non-ABA-fed plants. As a result, there were higher activities of photosynthetic electron transport, higher capacity of energy dissipation, and lower cumulation of excess light in cabbage than in rice plants, and in ABA-fed leaves than in non-ABA-fed leaves. The effect of ABA was more efficient in cabbage than in rice plants. Addition of exogenous ABA resulted in enhancement of the size of the xanthophyll cycle pool, promotion of de-epoxidation of the xanthophyll cycle components, and a rise in the level of NPQ by altering the kinetics of de-epoxidation of the xanthophyll cycle. Protection from photodamage appears to be achieved by coordinated contributions by exogenous ABA and xanthophyll cycle-mediated NPQ. This variety of photoprotective mechanisms may be essential for conferring photodamage tolerance under NaCl stress. © The Author [2011]. Published by Oxford University Press [on behalf of the Society for Experimental Biology]. All rights reserved.

Transgene Flow from Glufosinate-Resistant Rice to Improved and Weedy Rice in China

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Yong-liang LU

2014-09-01

Full Text Available The development of transgenic rice with novel traits in China can increase rice productivity, but transgene flow to improved or weedy rice has become a major concern. We aimed to evaluate the potential maximum frequencies of transgene flow from glufosinate-resistant rice to improved rice cultivars and weedy rice. Treatments were arranged in randomized complete blocks with three replicates. Experiments were conducted between 2009 and 2010 at the Center for Environmental Safety Supervision and Inspection for Genetically Modified Plants, China National Rice Research Institute, Hangzhou, China. Glufosinate-resistant japonica rice 99-1 was the pollen donor. The pollen recipients were two inbred japonica rice (Chunjiang 016 and Xiushui 09, two inbred indica rice (Zhongzu 14 and Zhongzao 22, two indica hybrid rice (Zhongzheyou 1 and Guodao 1, and one weedy indica rice (Taizhou weedy rice. The offspring of recipients were planted in the field and sprayed with a commercial dose of glufosinate. Leaf tissues of survivors were analyzed by polymerase chain reaction to detect the presence of the transgene. The frequency of gene flow ranged from 0 to 0.488%. In 2009, the order of gene flow frequency was as follows: weedy rice > Chunjiang 016 > Xiushui 09 and Zhongzu 14 > Guodao 1, Zhongzheyou 1 and Zhongzao 22. Gene flow frequencies were generally higher in 2009 than in 2010, but did not differ significantly among rice materials. Gene flow frequency was the highest in weedy rice followed by the inbred japonica rice. The risk of gene flow differed significantly between years and year-to-year variance could mask risk differences among pollen recipients. Gene flow was generally lesser in taller pollen recipients than in shorter ones, but plant height only accounted for about 30% of variation in gene flow. When flowering synchrony was maximized, as in this study, low frequencies of gene flow occurred from herbicide-resistant japonica rice to other cultivars and

Comparison of NH4+-N and NO3--N nutrition in hybrid and conventional rice at the late growth stage

International Nuclear Information System (INIS)

Yang Xiaoe; Sun Xi

1990-01-01

The difference of NH 4 + -N/NO 3 - -N nutrition between hybrid and conventional rice varieties at the late growth stage was studied by using 15 N-tracer technique. The results showed that the nitrate fertilizer utilization efficiency by the hybrid rice after anthesis was 7.8% higher than that by the ordinary rice variety, and the nitrate fertilizer recovery fraction by the former was 13.2% greater than that by the latter. The varietal difference in NO 3 - -N uptake and utilization was almost twice as that in NH 4 + -N. It was also showed that 15 N distribution in ear of the hybrid rice was about 20% greater than that of the conventional variety, but there were no obvious differences between NO 3 - -N and NH 4 + -N. However, 15 N distribution in the lower node leaves and root was found to be significant higher with NO 3 - -N than that with NH 4 + -N in both rice varieties, particularly in the hybrid rice. Compared with NH 4 + -N, NO 3 - -N top-dressing before anthesis was observed to have much greater positive effects on the uptake of calcium and magnesium and the growth of the superficial root and the grain yield of the tested rice varieties, especially of the hybrid rice

Investigating the roles of MicroRNAs in biotic stress response induced by Rhizoctonia solani in rice

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Syuhada, O. Nurfarahana; Kalaivani, N. [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2014-09-03

Sheath blight disease, caused by Rhizoctonia solani 1802/KB was screened on two rice varieties, Oryza sativaindica cultivar MR219 and Oryza sativa indica cultivar UKMRC9. The disease symptom was severe in MR219 compared to UKMRC9. Total RNA from R. solani 1802/KB, infected rice leaves of MR219 and infected rice leaves of UKMRC9 were extracted using TRIzol reagent, purified and sent for small RNA sequencing. Three miRNA libraries were generated and analyzed. The libraries generated 65 805, 78 512 and 81 325 known miRNAs respectively. The structure of miRNA of these samples was predicted. The up-regulated and down-regulated of miRNAs target gene prediction and its target functions were discovered and were mainly related to the growth and development of metabolism, protein transport, transcriptional regulation, stress response, and hormone signaling and electron transfer. Sheath blight-induced differential expression of known miRNAs tends to targetMYB transcription factor, F-box proteins, NBS-LRR, leucine-rich repeat receptor protein kinases and zinc finger proteins. Detecting new miRNAs and measuring the expression profiles of known miRNAs is an important tasks required for a better understanding of various biological conditions. Therefore, further analysis using Gene Ontology Slim will be conducted to deduce some biological information from the datasets obtained.

Rice production in relation to soil quality under different rice-based cropping systems

Science.gov (United States)

Tran Ba, Linh; Sleutel, Steven; Nguyen Van, Qui; Thi, Guong Vo; Le Van, Khoa; Cornelis, Wim

2016-04-01

Soil quality of shallow paddy soils may be improved by introducing upland crops and thus a more diverse crop cultivation pattern. Yet, the causal relationship between crop performance and enhanced soil traits in rice-upland crop rotations remains elusive. The objectives of this study were to (i) find correlations among soil properties under different rice-upland crop systems and link selected soil properties to rice growth and yield, (ii) present appropriate values of soil parameters for sustainable rice productivity in heavy clay soil, (iii) evaluate the effect of rotating rice with upland crops on rice yield and economic benefit in a long-term experiment. A rice-upland crop rotational field experiment in the Vietnamese Mekong delta was conducted for 10 years using a randomized complete block design with four treatments and four replications. Treatments were: (i) rice-rice-rice (control - conventional system as farmers' practice), (ii) rice-maize-rice, (iii) rice-mung bean-rice, and (iv) rice-mung bean-maize. Soil and plant sampling were performed after harvest of the rice crop at the end of the final winter-spring cropping season (i.e. year 10). Results show differences in rice growth and yield, and economic benefit as an effect of the crop rotation system. These differences were linked with changes in bulk density, soil porosity, soil aggregate stability index, soil penetration resistance, soil macro-porosity, soil organic carbon, acid hydrolysable soil C and soil nutrient elements, especially at soil depth of 20-30 cm. This is evidenced by the strong correlation (P < 0.01) between rice plant parameters, rice yield and soil properties such as bulk density, porosity, penetration resistance, soil organic carbon and Chydrolysable. It turned out that good rice root growth and rice yield corresponded to bulk density values lower than 1.3 Mg m-3, soil porosity higher than 50%, penetration resistance below 1.0 MPa, and soil organic carbon above 25 g kg-1. The optimal

The characteristics of pyrophosphate: D-fructose-6-phosphate 1-phosphotransferases from Sansevieria trifasciata leaves and Phaseolus coccineus stems.

Science.gov (United States)

Kowalczyk, S

1987-01-01

Three different molecular forms of pyrophosphate-dependent phosphofructokinase have been isolated: one from Sansevieria trifasciata leaves and two from Phaseolus coccineus stems. The form isolated from S. trifasciata has the molecular weight of about 115,000. The apparent molecular weights for the two forms from mung bean were approximately 220,000 and 450,000. All three forms have the same pH optima, an absolute requirement for Mg2+ ions both in the forward and reverse reaction, but differ in their sensitivity toward fructose 2,6-bisphosphate. Kinetic properties of the partially purified enzymes have been investigated in the presence and absence of fructose 2,6-bisphosphate. Pyrophosphate-dependent phosphofructokinase from S. trifasciata exhibited hyperbolic kinetics with all substrates tested. The saturation curves of the enzyme (form A) from mung bean for pyrophosphate, fructose 6-phosphate and fructose 1,6-bisphosphate were sigmoidal in the absence of fructose 2,6-bisphosphate. In the presence of fructose 2,6-bisphosphate these kinetics became hyperbolic.

RPAN: rice pan-genome browser for ∼3000 rice genomes.

Science.gov (United States)

Sun, Chen; Hu, Zhiqiang; Zheng, Tianqing; Lu, Kuangchen; Zhao, Yue; Wang, Wensheng; Shi, Jianxin; Wang, Chunchao; Lu, Jinyuan; Zhang, Dabing; Li, Zhikang; Wei, Chaochun

2017-01-25

A pan-genome is the union of the gene sets of all the individuals of a clade or a species and it provides a new dimension of genome complexity with the presence/absence variations (PAVs) of genes among these genomes. With the progress of sequencing technologies, pan-genome study is becoming affordable for eukaryotes with large-sized genomes. The Asian cultivated rice, Oryza sativa L., is one of the major food sources for the world and a model organism in plant biology. Recently, the 3000 Rice Genome Project (3K RGP) sequenced more than 3000 rice genomes with a mean sequencing depth of 14.3×, which provided a tremendous resource for rice research. In this paper, we present a genome browser, Rice Pan-genome Browser (RPAN), as a tool to search and visualize the rice pan-genome derived from 3K RGP. RPAN contains a database of the basic information of 3010 rice accessions, including genomic sequences, gene annotations, PAV information and gene expression data of the rice pan-genome. At least 12 000 novel genes absent in the reference genome were included. RPAN also provides multiple search and visualization functions. RPAN can be a rich resource for rice biology and rice breeding. It is available at http://cgm.sjtu.edu.cn/3kricedb/ or http://www.rmbreeding.cn/pan3k. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Isolation of Astilbin from Leaves of Cratoxylum Arborescens

International Nuclear Information System (INIS)

Samsiah Jusoh; Samsiah Jusoh; Zuriati Zakaria; Laily Din

2013-01-01

Phytochemicals studies was conducted on the leaves of Cratoxylum arborescens that has been collected from Post Brooke, Gua Musang, Kelantan, Malaysia. Traditionally, latex of the stem bark of C. arborescens is being used for the treatment of wound. Extraction of leaves of C. arborescens using organic solvents followed by purification using standard procedure of purification yielded known compound, astilbin. This compound was identified by NMR spectral data using various 2D-techniques and comparison with the literature data. Reports showed that this compound has a unique immunosuppressive activity, a selective inhibition against activated T lymphocytes. This characteristic of astilbin is beneficial for the treatment of human immune diseases. (author)

Analysis of rice purchase decision on rice consumer in Bandung city

Science.gov (United States)

Kusno, K.; Imannurdin, A.; Syamsiyah, N.; Djuwendah, E.

2018-03-01

This study was conducted at three kinds of purchase location which were traditional market, rice kiosk, and supermarket in Bandung City, with survey data of 108 respondents which were selected by systematic random sampling. The aim of this study is to (1) identify consumer characteristics, (2) identify which atribute is considered by consumer in buying rice, and (3) analyze the relationship between purchase decision and income class. Data were analyzed by descriptive analysis and Chi Square test. The results showed most consumers in the traditional market were middle-educated and lower middle-income, at the rice kiosk, the consumer were generally middle-educated and middle-income, and in the supermarkets, the majority were high-educated and upper middle-income consumers. “Kepulenan” be the first priority of most consumers, but for the lower-middle class, the main priority was price. Thus, in case of scarcity and rice price increase, the government should immediately arrange market operations which targeting to lower-middle class consumers. There was a significant relationship between (1) the quality of rice consumed, (2) the frequency of rice purchase per month, and (3) attitudes toward rice price increase; each with the income class. Although the price of rice increase, consumers of middle and upper-middle were remain loyal to the quality of rice they consumed. This indicates rice market in Bandung city is an ideal market for premium rice so that traders and producers are expected to maintain the quality of rice, such as keep using superior seeds and applying good cultivation based on Good Agricultural Practice (GAP) rules.

Nicotianamine synthase overexpression positively modulates iron homeostasis-related genes in high iron rice

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Meng eWang

2013-05-01

Full Text Available Nearly one-third of the world population, mostly women and children, suffer from iron malnutrition and its consequences, such as anemia or impaired mental development. Biofortification of rice, which is a staple crop for nearly half of the world’s population, can significantly contribute in alleviating iron deficiency. NFP rice (transgenic rice expressing nicotianamine synthase, ferritin and phytase genes has a more than six-fold increase in iron content in polished rice grains, resulting from the synergistic action of nicotianamine synthase (NAS and ferritin transgenes. We investigated iron homeostasis in NFP plants by analyzing the expression of 28 endogenous rice genes known to be involved in the homeostasis of iron and other metals, in iron-deficient and iron-sufficient conditions. RNA was collected from different tissues (roots, flag leaves, grains and at three developmental stages during grain filling. NFP plants showed increased sensitivity to iron-deficiency conditions and changes in the expression of endogenous genes involved in nicotianamine (NA metabolism, in comparison to their non-transgenic siblings. Elevated transcript levels were detected in NFP plants for several iron transporters. In contrast, expression of OsYSL2, which encodes a member of Yellow Stripe-like protein family, and a transporter of the NA-Fe(II complex was reduced in NFP plants under low iron conditions, indicating that expression of OsYSL2 is regulated by the endogenous iron status. Expression of the transgenes did not significantly affect overall iron homeostasis in NFP plants, which establishes the engineered push-pull mechanism as a suitable strategy to increase rice endosperm iron content.

In vitro schistosomicidal effects of aqueous and dichloromethane fractions from leaves and stems of Piper species and the isolation of an active amide from P. amalago L. (Piperaceae).

Science.gov (United States)

Carrara, V S; Vieira, S C H; de Paula, R G; Rodrigues, V; Magalhães, L G; Cortez, D A G; Da Silva Filho, A A

2014-09-01

Dichloromethane and aqueous fractions from leaves and stems of Piper arboreum Aubl., P. aduncum L., P. amalago L., P. crassinervium H.B. & K., P. diospyrifolium Kunth, P. hispidum Sw. and P. xylosteoides (Kunth) Steud. were tested against adult worms of Schistosoma mansoni. The in vitro activity was evaluated in terms of mortality, number of separated worms and number of worms with reduced motor activity. Most dichloromethane fractions from all Piper species showed moderate schistosomicidal activity, but aqueous fractions were not active. The dichloromethane fraction of P. amalago leaves (at 100 μg/ml) showed the highest activity, resulting in worm mortality, the separation of worm pairs and reduced motor activity. Chromatographic fractionation of the dichloromethane fraction of P. amalago leaves led to the isolation of its major compound, which was also tested against adults of S. mansoni. The isolated piperamide N-[7-(3',4'-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl] pyrrolidine, at 100 μ m, resulted in the mortality of all adult worms after 24 h of incubation. The findings suggest that species of Piper are potential sources of schistosomicidal compounds.

Genetically engineered rice. The source of β-carotene

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Karol Terlecki

2014-04-01

Full Text Available β-carotene is a precursor of vitamin A. It is converted to vitamin A in the humans intestine by the β-carotene-15,15’-monooxygenase. Vitamin A is essential to support vision, as an antioxidant it protects the body from free radicals, it helps to integrate the immune system, as well as takes part in cellular differentiation and proliferation. Vitamin A deficiency is a major public health problem especially among developing countries. Nyctalopia, commonly known as „Night Blindness” is one of the major symptoms of Vitamin A deficiency (VAD. Plants such as apricots, broccoli, carrots, and sweet potatoes are rich in β-carotene. Some of the plants are characterized by a higher content of provitamin-A. Among vegetables rich sources of β-carotene are: carrots, pumpkin, spinach, lettuce, green peas, tomatoes, watercress, broccoli and parsley leaves. Amongst fruits the highest content of β-carotene is in apricot, cherry, sweet cherry, plum, orange and mango. The aim of the present study was to analyze available literature data of increasing the content of β-carotene in genetically engineered rice. The genetically modified cultivar contains additional genes: PSY and CRTI thanks to which rice seed endosperm contains β-carotene. Genetically engineered rice with β-carotene is an effective source of vitamin A, it contains approximately 30 μg β-carotene per 1 g. Fortunately some of the advantages of Genetically Modified Food give an opportunity to reduce VAD worldwide, by introducing the rice which has been genetically engineered to be rich in β-carotene. The popularity of this plant as an element of nutrition is simultaneously a source of vitamin A.

Conversion of the fungicide, ziram in rice plants

International Nuclear Information System (INIS)

Kumarasamy, R.; Raghu, K.

1976-01-01

Zinc dimethyldithiocarbamate (ziram) is a toliar fungicide used for the control of the blast disease of rice caused by Pyricularia oryzae, and is also used for the control of the plant diseases in crops like groundnut, cotton, etc. Since there is lack of data on the conversion products of this fungicide. This investigation was carried out. The results of the author's recent studies with 35 S-labelled ziram in rice seedlings were reported. The 35 S-Labelled ziram (specific activity 1.5 m Ci/m mole) was sprayed on the rice seedlings of 25 days old. At different intervals of time, the seedlings were removed, washed thoroughly, cut into pieces, and extracted with 80% ethanol. By the method described in ''K. Raghu et al., Origin and fate of chemical residents in food, agriculture and fisheries, I.A.E.A., Vienna, 1975, pp. 137-148,'' the segments corresponding to the standards of dimethyl dithio carbamate-alanine (DDCA), DDC-glucoside (DDCG), thiazolidine-2-thione-4-carbamic acid (TTCA), unidentified divolent fungicide (X), and ziram were cut out and the radioactivity was counted in cocktail D scintillation fluid using an LS-100 Beckmann liquid scintillation counter. It is indeed interesting to note that ziram is converted in plant tissues into dimethyldithiocarbamate derivatives like DDCG, DDCA, TTCA and X within 24 hr after spraying. The amounts of these derivatives varied in the course of sampling up to 8 days after spraying. Further studies are needed as to the quantitative nature of these products, but the present report clearly demonstrates the formation of these conversion products in the rice leaves treated with ziram. (Kobatake, H.)

Improved short-stature rice created by radiation-induced mutation

International Nuclear Information System (INIS)

1977-01-01

A new mutant variety of rice, named Calrose 76, has recently been released to farmers in California. The mutant was the result of irradiating seeds of the rice variety Calrose with gamma rays from a cobalt-60 source. The variety is the result of co-operative research between Dr. J.N. Rutger, U.S. Department of Agriculture research geneticist at Davis, California, Prof. M.L. Peterson, University of California, and Dr. Chao-Hwa Hu, an IAEA fellow. The mutant that was ultimately released as a new variety was selected in the second generation following irradiation of the Calrose seeds. Selections were also made in a non-irradiated control population, but none proved to be desirable. After its selection in 1971, the mutant was subsequently tested for several years for agronomic performance, grain yield and quality characteristics. It was found to have the same yielding capacity as the widely grown check variety, CS-M3. It also did not differ in seedling vigour or in heading date, but its mature stem is about 35 cm shorter and less susceptible to lodging. Therefore, it yields more grain under conditions of high soil fertility. The short stature is inherited by a single recessive gene, allelic to the gene for short stature widely used in rice cultivars of the International Rice Research Institute in the Philippines (IRRI). The radiation-induced mutant has the advantage that the gene for short stature now exists in a genotype which is adapted to Californian conditions and which possesses the required cold tolerance and grain qualities. Attempts to transfer short stature from the tropical variety IR8 (produced by IRRI) have been complicated by sterility, cold susceptibility, and unacceptable grain quality. The radiation-induced mutant is used now also in crosses to confer the desired short stature to other rice varieties. (author)

Improved short-stature rice created by radiation-induced mutation

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-06-15

A new mutant variety of rice, named Calrose 76, has recently been released to farmers in California. The mutant was the result of irradiating seeds of the rice variety Calrose with gamma rays from a cobalt-60 source. The variety is the result of co-operative research between Dr. J.N. Rutger, U.S. Department of Agriculture research geneticist at Davis, California, Prof. M.L. Peterson, University of California, and Dr. Chao-Hwa Hu, an IAEA fellow. The mutant that was ultimately released as a new variety was selected in the second generation following irradiation of the Calrose seeds. Selections were also made in a non-irradiated control population, but none proved to be desirable. After its selection in 1971, the mutant was subsequently tested for several years for agronomic performance, grain yield and quality characteristics. It was found to have the same yielding capacity as the widely grown check variety, CS-M3. It also did not differ in seedling vigour or in heading date, but its mature stem is about 35 cm shorter and less susceptible to lodging. Therefore, it yields more grain under conditions of high soil fertility. The short stature is inherited by a single recessive gene, allelic to the gene for short stature widely used in rice cultivars of the International Rice Research Institute in the Philippines (IRRI). The radiation-induced mutant has the advantage that the gene for short stature now exists in a genotype which is adapted to Californian conditions and which possesses the required cold tolerance and grain qualities. Attempts to transfer short stature from the tropical variety IR8 (produced by IRRI) have been complicated by sterility, cold susceptibility, and unacceptable grain quality. The radiation-induced mutant is used now also in crosses to confer the desired short stature to other rice varieties. (author)

Lead toxicity in rice: effects, mechanisms, and mitigation strategies--a mini review.

Science.gov (United States)

Ashraf, Umair; Kanu, Adam Sheka; Mo, Zhaowen; Hussain, Saddam; Anjum, Shakeel Ahmad; Khan, Imran; Abbas, Rana Nadeem; Tang, Xiangru

2015-12-01

Lead (Pb) is a major environmental pollutant that affects plant morpho-physiological and biochemical attributes. Its higher levels in the environment are not only toxic to human beings but also harmful for plants and soil microbes. We have reviewed the uptake, translocation, and accumulation mechanisms of Pb and its toxic effects on germination, growth, yield, nutrient relation, photosynthesis, respiration, oxidative damage, and antioxidant defense system of rice. Lead toxicity hampers rice germination, root/shoot length, growth, and final yield. It reduces nutrient uptake through roots, disrupts chloroplastic ultrastructure and cell membrane permeability, induces alterations in leaves respiratory activities, produces reactive oxygen species (ROS), and triggers some enzyme and non-enzymatic antioxidants (as defense to oxidative damage). In the end, biochar amendments and phytoremediation technologies have been proposed as soil remediation approaches for Pb tainted soils.

A Rice CPYC-Type Glutaredoxin OsGRX20 in Protection against Bacterial Blight, Methyl Viologen and Salt Stresses

Directory of Open Access Journals (Sweden)

Xi Ning

2018-02-01

Full Text Available Glutaredoxins (GRXs belong to the antioxidants involved in the cellular stress responses. In spite of the identification 48 GRX genes in rice genomes, the biological functions of most of them remain unknown. Especially, the biological roles of members of GRX family in disease resistance are still lacking. Our proteomic analysis found that OsGRX20 increased by 2.7-fold after infection by bacterial blight. In this study, we isolated and characterized the full-length nucleotide sequences of the rice OsGRX20 gene, which encodes a GRX family protein with CPFC active site of CPYC-type class. OsGRX20 protein was localized in nucleus and cytosol, and its transcripts were expressed predominantly in leaves. Several stress- and hormone-related motifs putatively acting as regulatory elements were found in the OsGRX20 promoter. Real-time quantitative PCR analysis indicated that OsGRX20 was expressed at a significantly higher level in leaves of a resistant or tolerant rice genotype, Yongjing 50A, than in a sensitive genotype, Xiushui 11, exposed to bacterial blight, methyl viologen, heat, and cold. Its expression could be induced by salt, PEG-6000, 2,4-D, salicylic acid, jasmonic acid, and abscisic acid treatments in Yongjing 50A. Overexpression of OsGRX20 in rice Xiushui 11 significantly enhanced its resistance to bacterial blight attack, and tolerance to methyl viologen and salt stresses. In contrast, interference of OsGRX20 in Yongjing 50A led to increased susceptibility to bacterial blight, methyl viologen and salt stresses. OsGRX20 restrained accumulation of superoxide radicals in aerial tissue during methyl viologen treatment. Consistently, alterations in OsGRX20 expression affect the ascorbate/dehydroascorbate ratio and the abundance of transcripts encoding four reactive oxygen species scavenging enzymes after methyl viologen-induced stress. Our results demonstrate that OsGRX20 functioned as a positive regulator in rice tolerance to multiple stresses

PhosphoRice: a meta-predictor of rice-specific phosphorylation sites

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Que Shufu

2012-02-01

Full Text Available Abstract Background As a result of the growing body of protein phosphorylation sites data, the number of phosphoprotein databases is constantly increasing, and dozens of tools are available for predicting protein phosphorylation sites to achieve fast automatic results. However, none of the existing tools has been developed to predict protein phosphorylation sites in rice. Results In this paper, the phosphorylation site predictors, NetPhos 2.0, NetPhosK, Kinasephos, Scansite, Disphos and Predphosphos, were integrated to construct meta-predictors of rice-specific phosphorylation sites using several methods, including unweighted voting, unreduced weighted voting, reduced unweighted voting and weighted voting strategies. PhosphoRice, the meta-predictor produced by using weighted voting strategy with parameters selected by restricted grid search and conditional random search, performed the best at predicting phosphorylation sites in rice. Its Matthew's Correlation Coefficient (MCC and Accuracy (ACC reached to 0.474 and 73.8%, respectively. Compared to the best individual element predictor (Disphos_default, PhosphoRice archieved a significant increase in MCC of 0.071 (P Conclusions PhosphoRice is a powerful tool for predicting unidentified phosphorylation sites in rice. Compared to the existing methods, we found that our tool showed greater robustness in ACC and MCC. PhosphoRice is available to the public at http://bioinformatics.fafu.edu.cn/PhosphoRice.

Atmospheric dinitrogen fixation in the flooded rhizosphere as determined by the N-15 isotope technique

International Nuclear Information System (INIS)

Yoshida, Tomio; Yoneyama, Tadakatsu.

1980-01-01

Atmospheric nitrogen fixation in the rice rhizosphere was determined under in situ conditions of growing flooded rice using the N-15 isotope method. The whole plant growing in a pot at a reproductive stage was placed in a specially designed glass container and exposed to a 15 N 2 atmosphere. The amounts of total nitrogen fixed in the rice rhizosphere under the experimental conditions were 1366, 592, 878, and 698 μg per pot containing 0.4 kg of soil during 15 N 2 exposure for 7 to 13 days in the four experiments conducted in this study. It was also found that the nitrogen fixed in the rice rhizosphere was translocated into other plant parts. Nineteen to 25% of the total atmospheric nitrogen fixed in the rice rhizosphere was found in the roots, leaves and stems, and ears of the rice plants during the 15 N 2 exposure period. (author)

Three novel rice genes closely related to the Arabidopsis IRX9, IRX9L, and IRX14 genes and their roles in xylan biosynthesis

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Dawn eChiniquy

2013-04-01

Full Text Available Xylan is the second most abundant polysaccharide on Earth, and represents a major component of both dicot wood and the cell walls of grasses. Much knowledge has been gained from studies of xylan biosynthesis in the model plant, Arabidopsis. In particular, the irregular xylem (irx mutants, named for their collapsed xylem cells, have been essential in gaining a greater understanding of the genes involved in xylan biosynthesis. In contrast, xylan biosynthesis in grass cell walls is poorly understood. We identified three rice genes Os07g49370 (OsIRX9, Os01g48440 (OsIRX9L, and Os06g47340 (OsIRX14, from glycosyltransferase family 43 as putative orthologs to the putative β-1,4-xylan backbone elongating Arabidopsis IRX9, IRX9L, and IRX14 genes, respectively. We demonstrate that the overexpression of the closely related rice genes, in full or partly complement the two well-characterized Arabidopsis irregular xylem (irx mutants: irx9 and irx14. Complementation was assessed by measuring dwarfed phenotypes, irregular xylem cells in stem cross sections, xylose content of stems, xylosyltransferase activity of stems, and stem strength. The expression of OsIRX9 in the irx9 mutant resulted in xylosyltransferase activity of stems that was over double that of wild type plants, and the stem strength of this line increased to 124% above that of wild type. Taken together, our results suggest that OsIRX9/OsIRX9L, and OsIRX14, have similar functions to the Arabidopsis IRX9 and IRX14 genes, respectively. Furthermore, our expression data indicate that OsIRX9 and OsIRX9L may function in building the xylan backbone in the secondary and primary cell walls, respectively. Our results provide insight into xylan biosynthesis in rice and how expression of a xylan synthesis gene may be modified to increase stem strength.

Determination of a various ions such as alkali metals in leaves, stems, roots and seeds of the radish and their distribution

International Nuclear Information System (INIS)

Fujino, Osamu; Matsui, Masakazu.

1995-01-01

Determination, uptake and distribution of various ions such as alkali metals in three different parts (leaf, stem and root) and seeds of radish (Kaiware daikon) were examined using flame emission spectrometry and ICP-AES. In order to examine the influence of concentration alkali metal ion concentration in the radish culture solution on the uptake and distribution of these metals, the radish was grown at pH 5.6 in solutions containing alkali metal chloride at concentrations ranging from 10 -5 to 10 -1 mol dm -3 . When the radish were grown in culture solution with alkali metal ions of low concentrations (10 -5 and 10 -4 mol dm -3 ), Na, K, Rb and trace Li were detected in leaves, stems and roots while Cs was scarcely detected. However, the contents of Na, K, Li in these organs were the same as those in radish cultivated in pure water. An increase of Rb uptake was observed with an increased Rb concentration. In the case of high concentrations (10 -3 and 10 -2 mol dm -3 ) of alkali metals in culture solution, the all alkali ions uptake of all alkali ions suddenly accelerated. Moreover, at concentrations higher than 0.1 mol dm -3 , the radish germinated poorly and did not completely mature. (author)

[Nitrogen cycling in rice-duck mutual ecosystem during double cropping rice growth season].

Science.gov (United States)

Zhang, Fan; Chen, Yuan-Quan; Sui, Peng; Gao, Wang-Sheng

2012-01-01

Raising duck in paddy rice field is an evolution of Chinese traditional agriculture. In May-October 2010, a field experiment was conducted in a double cropping rice region of Hunan Province, South-central China to study the nitrogen (N) cycling in rice-duck mutual ecosystem during early rice and late rice growth periods, taking a conventional paddy rice field as the control. Input-output analysis method was adopted. The N output in the early rice-duck mutual ecosystem was 239.5 kg x hm(-2), in which, 12.77 kg x hm(-2) were from ducks, and the N output in the late rice-duck mutual ecosystem was 338.7 kg x hm(-2), in which, 23.35 kg x hm(-2) were from ducks. At the present N input level, there existed soil N deficit during the growth seasons of both early rice and late rice. The N input from duck sub-system was mainly from the feed N, and the cycling rate of the duck feces N recycled within the system was 2.5% during early rice growth season and 3.5% during late rice growth season. After late rice harvested, the soil N sequestration was 178.6 kg x hm(-2).

Integrating independent research into science curricula to foster STEM leadership

Science.gov (United States)

Queenan, Craig; Calabro, Alyssa; Becker, David

2013-05-01

Preparing students for college and future careers is one of the main goals of K-12 education, but current STEM teaching methods do not do enough to interest students and leave them prepared to enter into and succeed in STEM careers. While measures to implement unifying standards for science education across the country are aimed at ensuring that all students are taught the same material at each grade level, a shift in the way science is taught to is needed to complete the redesign of science education. The independent research model described here aligns with the new content standards and focuses on developing the principles of perspective, purpose, resources, collaboration, analysis, and presentation. These principles not only engage students in the classroom, but also leave students prepared to enter into science programs in college and succeed in leadership roles in the STEM workforce.

Effects of Extraction Methods on Phytochemicals of Rice Bran Oils Produced from Colored Rice.

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Mingyai, Sukanya; Srikaeo, Khongsak; Kettawan, Aikkarach; Singanusong, Riantong; Nakagawa, Kiyotaka; Kimura, Fumiko; Ito, Junya

2018-02-01

Rice bran oil (RBO) especially from colored rice is rich in phytochemicals and has become popular in food, cosmetic, nutraceutical and pharmaceutical applications owing to its offering health benefits. This study determined the contents of phytochemicals including oryzanols, phytosterols, tocopherols (Toc) and tocotrienols (T3) in RBOs extracted using different methods namely cold-press extraction (CPE), solvent extraction (SE) and supercritical CO 2 extraction (SC-CO 2 ). Two colored rice, Red Jasmine rice (RJM, red rice) and Hom-nin rice (HN, black rice), were studied in comparison with the popular Thai fragrant rice Khao Dawk Mali 105 (KDML 105, white rice). RBOs were found to be the rich source of oryzanols, phytosterols, Toc and T3. Rice varieties had a greater effect on the phytochemicals concentrations than extraction methods. HN rice showed the significantly highest concentration of all phytochemicals, followed by RJM and KDML 105 rice, indicating that colored rice contained high concentration of phytochemicals in the oil than non-colored rice. The RBO samples extracted by the CPE method had a greater concentration of the phytochemicals than those extracted by the SC-CO 2 and SE methods, respectively. In terms of phytochemical contents, HN rice extracted using CPE method was found to be the best.

Isolation of stress responsive Psb A gene from rice (Oryza sativa l.) using differential display.

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Tyagi, Aruna; Chandra, Arti

2006-08-01

Differential display (DD) experiments were performed on drought-tolerant rice (Oryza sativa L.) genotype N22 to identify both upregulated and downregulated partial cDNAs with respect to moisture stress. DNA polymorphism was detected between drought-stressed and control leaf tissues on the DD gels. A partial cDNA showing differential expression, with respect to moisture stress was isolated from the gel. Northern blotting analysis was performed using this cDNA as a probe and it was observed that mRNA corresponding to this transcript was accumulated to high level in rice leaves under water deficit stress. At the DNA sequence level, the partial cDNA showed homology with psb A gene encoding for Dl protein.

Equol, a Clinically Important Metabolite, Inhibits the Development and Pathogenicity of Magnaporthe oryzae, the Causal Agent of Rice Blast Disease

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Jiaoyu Wang

2017-10-01

Full Text Available Equol, a metabolite of soybean isoflavone daidzein, has been proven to have various bioactivities related to human health, but little is known on its antifungal activity to plant fungal pathogens. Magnaporthe oryzae is a phytopathogenic fungus that causes rice blast, a devastating disease on rice. Here, we demonstrated that equol influences the development and pathogenicity of M. oryzae. Equol showed a significant inhibition to the mycelial growth, conidial generation and germination, and appressorial formation of M. oryzae. As a result, equol greatly reduced the virulence of M. oryzae on rice and barley leaves. The antifungal activity of equol was also found in several other plant fungal pathogens. These findings expand our knowledge on the bioactivities of equol.

Screening and Expression of a Silicon Transporter Gene (Lsi1) in Wild-Type Indica Rice Cultivars

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Abiri, Rambod; Kalhori, Nahid; Atabaki, Narges

2017-01-01

Silicon (Si) is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties. PMID:28191468

Screening and Expression of a Silicon Transporter Gene (Lsi1 in Wild-Type Indica Rice Cultivars

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Mahbod Sahebi

2017-01-01

Full Text Available Silicon (Si is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties.

Screening and Expression of a Silicon Transporter Gene (Lsi1) in Wild-Type Indica Rice Cultivars.

Science.gov (United States)

Sahebi, Mahbod; Hanafi, Mohamed M; Rafii, M Y; Azizi, Parisa; Abiri, Rambod; Kalhori, Nahid; Atabaki, Narges

2017-01-01

Silicon (Si) is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties.

Fluid drag reduction and efficient self-cleaning with rice leaf and butterfly wing bioinspired surfaces

Science.gov (United States)

Bixler, Gregory D.; Bhushan, Bharat

2013-08-01

Researchers are continually inspired by living nature to solve complex challenges. For example, unique surface characteristics of rice leaves and butterfly wings combine the shark skin (anisotropic flow leading to low drag) and lotus leaf (superhydrophobic and self-cleaning) effects, producing the so-called rice and butterfly wing effect. In this paper, we present an overview of rice leaf and butterfly wing fluid drag and self-cleaning studies. In addition, we examine two other promising aquatic surfaces in nature known for such properties, including fish scales and shark skin. Morphology, drag, self-cleaning, contact angle, and contact angle hysteresis data are presented to understand the role of wettability, viscosity, and velocity. Liquid repellent coatings are utilized to recreate or combine various effects. Discussion is provided along with conceptual models describing the role of surface structures related to low drag, self-cleaning, and antifouling properties. Modeling provides design guidance when developing novel low drag and self-cleaning surfaces for applications in the medical, marine, and industrial fields.

Differentially expressed genes distributed over chromosomes and implicated in certain biological processes for site insertion genetically modified rice Kemingdao.

Science.gov (United States)

Liu, Zhi; Li, Yunhe; Zhao, Jie; Chen, Xiuping; Jian, Guiliang; Peng, Yufa; Qi, Fangjun

2012-01-01

Release of genetically modified (GM) plants has sparked off intensive debates worldwide partly because of concerns about potential adverse unintended effects of GM plants to the agro system and the safety of foods. In this study, with the aim of revealing the molecular basis for unintended effects of a single site insertion GM Kemingdao (KMD) rice transformed with a synthetic cry1Ab gene, and bridging unintended effects of KMD rice through clues of differentially expressed genes, comparative transcriptome analyses were performed for GM KMD rice and its parent rice of Xiushui11 (XS11). The results showed that 680 differentially expressed transcripts were identified from 30-day old seedlings of GM KMD rice. The absolute majority of these changed expression transcripts dispersed and located over all rice chromosomes, and existed physical distance on chromosome from the insertion site, while only two transcripts were found to be differentially expressed within the 21 genes located within 100 kb up and down-stream of the insertion site. Pathway and biology function analyses further revealed that differentially expressed transcripts of KMD rice were involved in certain biological processes, and mainly implicated in two types of pathways. One type was pathways implicated in plant stress/defense responses, which were considerably in coordination with the reported unintended effects of KMD rice, which were more susceptible to rice diseases compared to its parent rice XS11; the other type was pathways associated with amino acids metabolism. With this clue, new unintended effects for changes in amino acids synthesis of KMD rice leaves were successfully revealed. Such that an actual case was firstly provided for identification of unintended effects in GM plants by comparative transciptome analysis.

Fundamental and molecular composition characteristics of biochars produced from sugarcane and rice crop residues and by-products.

Science.gov (United States)

Jeong, Chang Yoon; Dodla, Syam K; Wang, Jim J

2016-01-01

Biochar conversion of sugarcane and rice harvest residues provides an alternative for managing these crop residues that are traditionally burned in open field. Sugarcane leaves, bagasse, rice straw and husk were converted to biochar at four pyrolysis temperatures (PTs) of 450 °C, 550 °C, 650 °C, and 750 °C and evaluated for various elemental, molecular and surface properties. The carbon content of biochars was highest for those produced at 650-750 °C. Biochars produced at 550 °C showed the characteristics of biochar that are commonly interpreted as being stable in soil, with low H/C and O/C ratios and pyrolysis fingerprints dominated by aromatic and polyaromatic hydrocarbons. At 550 °C, all biochars also exhibited maximum CEC values with sugarcane leaves biochar (SLB) > sugarcane bagasse biochar (SBB) > rice straw biochar (RSB) > rice husk biochar (RHB). The pore size distribution of biochars was dominated by pores of 20 nm and high PT increased both smaller and larger than 50 nm pores. Water holding capacity of biochars increased with PT but the magnitude of the increase was limited by feedstock types, likely related to the hydrophobicity of biochars as evident by molecular composition, besides pore volume properties of biochars. Py-GC/MS analysis revealed a clear destruction of lignin with decarboxylation and demethoxylation at 450 °C and dehydroxylation at above 550 °C. Overall, biochar molecular compositions became similar as PT increased, and the biochars produced at 550 °C demonstrated characteristics that have potential benefit as soil amendment for improving both C sequestration and nutrient dynamics. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mitigation effects of silicon rich amendments on heavy metal accumulation in rice (Oryza sativa L.) planted on multi-metal contaminated acidic soil.

Science.gov (United States)

Gu, Hai-Hong; Qiu, Hao; Tian, Tian; Zhan, Shu-Shun; Deng, Teng-Hao-Bo; Chaney, Rufus L; Wang, Shi-Zhong; Tang, Ye-Tao; Morel, Jean-Louis; Qiu, Rong-Liang

2011-05-01

The mechanisms of stabilization by silicon-rich amendments of cadmium, zinc, copper and lead in a multi-metal contaminated acidic soil and the mitigation of metal accumulation in rice were investigated in this study. The results from a pot experiment indicated that the application of fly ash (20 and 40gkg(-1)) and steel slag (3 and 6gkg(-1)) increased soil pH from 4.0 to 5.0-6.4, decreased the phytoavailability of heavy metals by at least 60%, and further suppressed metal uptake by rice. Diffusion gradient in thin-film measurement showed the heavy metal diffusion fluxes from soil to solution decreased by greater than 84% after remediation. X-ray diffraction analysis indicated the mobile metals were mainly deposited as their silicates, phosphates and hydroxides in amended treatments. Moreover, it was found metal translocation from stem to leaf was dramatically restrained by adding amendments, which might be due to the increase of silicon concentration and co-precipitation with heavy metals in stem. Finally, a field experiment showed the trace element concentrations in polished rice treated with amendments complied with the food safety standards of China. These results demonstrated fly ash and steel slag could be effective in mitigating heavy metal accumulation in rice grown on multi-metal contaminated acidic soils. Copyright © 2011 Elsevier Ltd. All rights reserved.

Ectopic expression of ubiquitin-conjugating enzyme gene from wild rice, OgUBC1, confers resistance against UV-B radiation and Botrytis infection in Arabidopsis thaliana

International Nuclear Information System (INIS)

Jeon, En Hee; Pak, Jung Hun; Kim, Mi Jin; Kim, Hye Jeong; Shin, Sang Hyun; Lee, Jai Heon; Kim, Doh Hoon; Oh, Ju Sung; Oh, Boung-Jun; Jung, Ho Won; Chung, Young Soo

2012-01-01

Highlights: ► We isolated a novel E2 ubiquitin-conjugating enzyme from leaves of wild rice plants. ► The OgUBC1 was highly expressed in leaves treated with SA and UV-B radiation. ► The recombinant OgUBC1 has an enzymatic activity of E2 in vitro. ► The OgUBC1 could protect disruption of plant cells by UV-B radiation. ► OgUBC1 confers disease resistance and UV-B tolerance in transgenic Arabidopsis plants. -- Abstract: A previously unidentified gene encoding ubiquitin-conjugating enzyme was isolated from leaves of wild rice plant treated with wounding and microbe-associated molecular patterns. The OgUBC1 gene was composed of 148 amino acids and contained a typical active site and 21 ubiquitin thioester intermediate interaction residues and 4 E3 interaction residues. Both exogenous application of salicylic acid and UV-B irradiation triggered expression of OgUBC1 in leaves of wild rice. Recombinant OgUBC1 proteins bound to ubiquitins in vitro, proposing that the protein might act as E2 enzyme in planta. Heterologous expression of the OgUBC1 in Arabidopsis thaliana protected plants from cellular damage caused by an excess of UV-B radiation. A stable expression of chalcone synthase gene was detected in leaves of OgUBC1-expressing Arabidopsis, resulting in producing higher amounts of anthocyanin than those in wild-type Col-0 plants. Additionally, both pathogenesis-related gene1 and 5 were transcribed in the transgenic Arabidopsis in the absence of pathogen infection. The OgUBC1-expressing plants were resistant to the infection of Botrytis cinerea. Taken together, we suggested that the OgUBC1 is involved in ubiquitination process important for cellular response against biotic and abiotic stresses in plants.

Ectopic expression of ubiquitin-conjugating enzyme gene from wild rice, OgUBC1, confers resistance against UV-B radiation and Botrytis infection in Arabidopsis thaliana

Energy Technology Data Exchange (ETDEWEB)

Jeon, En Hee; Pak, Jung Hun; Kim, Mi Jin; Kim, Hye Jeong [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of); Shin, Sang Hyun [National Crop Experiment Station, Rural Development Administration, Suwon 441-100 (Korea, Republic of); Lee, Jai Heon; Kim, Doh Hoon; Oh, Ju Sung [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of); Oh, Boung-Jun [BioControl Center, Jeonnam 516-942 (Korea, Republic of); Jung, Ho Won, E-mail: hwjung@dau.ac.kr [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of); Chung, Young Soo, E-mail: chungys@dau.ac.kr [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of)

2012-10-19

Highlights: Black-Right-Pointing-Pointer We isolated a novel E2 ubiquitin-conjugating enzyme from leaves of wild rice plants. Black-Right-Pointing-Pointer The OgUBC1 was highly expressed in leaves treated with SA and UV-B radiation. Black-Right-Pointing-Pointer The recombinant OgUBC1 has an enzymatic activity of E2 in vitro. Black-Right-Pointing-Pointer The OgUBC1 could protect disruption of plant cells by UV-B radiation. Black-Right-Pointing-Pointer OgUBC1 confers disease resistance and UV-B tolerance in transgenic Arabidopsis plants. -- Abstract: A previously unidentified gene encoding ubiquitin-conjugating enzyme was isolated from leaves of wild rice plant treated with wounding and microbe-associated molecular patterns. The OgUBC1 gene was composed of 148 amino acids and contained a typical active site and 21 ubiquitin thioester intermediate interaction residues and 4 E3 interaction residues. Both exogenous application of salicylic acid and UV-B irradiation triggered expression of OgUBC1 in leaves of wild rice. Recombinant OgUBC1 proteins bound to ubiquitins in vitro, proposing that the protein might act as E2 enzyme in planta. Heterologous expression of the OgUBC1 in Arabidopsis thaliana protected plants from cellular damage caused by an excess of UV-B radiation. A stable expression of chalcone synthase gene was detected in leaves of OgUBC1-expressing Arabidopsis, resulting in producing higher amounts of anthocyanin than those in wild-type Col-0 plants. Additionally, both pathogenesis-related gene1 and 5 were transcribed in the transgenic Arabidopsis in the absence of pathogen infection. The OgUBC1-expressing plants were resistant to the infection of Botrytis cinerea. Taken together, we suggested that the OgUBC1 is involved in ubiquitination process important for cellular response against biotic and abiotic stresses in plants.

DETERMINATION OF SPATIAL INTEGRATION AND SUBSTITUTION OF FOREIGN RICE FOR LOCAL RICE IN GHANA

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Philip Kofi ADOM

2014-11-01

Full Text Available This study tested for spatial integration in the rice market and the substitution of imported rice for local rice in Ghana. It is established that the markets for domestic imported rice are well-integrated, but not complete. The imperfect spatial integration of domestic foreign rice markets implies that the market provides opportunities for arbitrage. Price leadership roles are found to be determined by the kind of sub-inter-regional-trade network defined. However, in all, the Accra market emerged as a dominant market leader in the domestic foreign rice market. There is evidence of significant regional substitution of foreign rice for local rice in the long run, but the result is mixed in the short run. The result that local rice is not a perfect substitute for imported rice implies that price disincentive measures such as increasing the import tariffs on foreign rice will only produce a mild effect on increasing the producer price faced by local rice farmers, but aggravate the burden on households’ budget.

Involvement of NADPH oxidase isoforms in the production of O2- manipulated by ABA in the senescing leaves of early-senescence-leaf (esl) mutant rice (Oryza sativa).

Science.gov (United States)

Li, Zhaowei; Wang, Fubiao; Zhao, Qian; Liu, Jianchao; Cheng, Fangmin

2018-01-01

In this study, the differences in reactive oxygen species (ROS) generation and abscisic acid (ABA) accumulation in senescing leaves were investigated by early-senescence-leaf (esl) mutant and its wild type, to clarify the relationship among ABA levels, ROS generation, and NADPH oxidase (Nox) in senescing leaves of rice (Oryza sativa). The temporal expression levels of OsNox isoforms in senescing leaves and their expression patterns in response to ABA treatment were determined through quantitative real-time reverse transcription PCR (qRT-PCR). Results showed that the flag leaf of the esl mutant generated more O2- concentrations and accumulated higher ABA levels than the wild-type cultivar did in the grain-filling stage. Exogenous ABA treatment induced O2- generation; however, it was depressed by diphenyleneiodonium chloride (DPI) pretreatment in the detached leaf segments. This finding suggested the involvement of NADPH oxidase in ABA-induced O2- generation. The esl mutant exhibited significantly higher expression of OsNox2, OsNox5, OsNox6, and OsNox7 in the initial of grain-filling stage, followed by sharply decrease. The transcriptional levels of OsNox1, OsNox3, and OsFR07 in the flag leaf of the esl mutant were significantly lower than those in the wild-type cultivar. The expression levels of OsNox2, OsNox5, OsNox6, and OsNox7 were significantly enhanced by exogenous ABA treatments. The enhanced expression levels of OsNox2 and OsNox6 were dependent on the duration of ABA treatment. The inducible expression levels of OsNox5 and OsNox7 were dependent on ABA concentrations. By contrast, exogenous ABA treatment severely repressed the transcripts of OsNox1, OsNox3, and OsFR07 in the detached leaf segments. Therefore, OsNox2, OsNox5, OsNox6, and OsNox7 were probably involved in the ABA-induced O2- generation in the initial stage of leaf senescence. Subsequently, other oxidases activated in deteriorating cells were associated with ROS generation and accumulation in the

Wheat Yield Trend and Soil Fertility Status in Long Term Rice-Rice-Wheat Cropping System

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Nabin Rawal

2015-12-01

Full Text Available A long-term soil fertility experiment under rice-rice-wheat system was performed to evaluate the long term effects of inorganic fertilizer and manure applications on soil properties and grain yield of wheat. The experiment began since 1978 was laid out in randomized complete block design with 9 treatments replicated 3 times. From 1990 onwards, periodic modifications have been made in all the treatments splitting the plots in two equal halves of 4 x 3 m2 leaving one half as original. In the original treatments, recent data revealed that the use of Farm Yard Manure (FYM @10 t ha-1 gave significantly (P≤0.05 higher yield of 2.3 t ha-1 in wheat, whereas control plot gave the lowest grain yield of 277 kg ha-1. Similarly, in the modified treatments, the use of FYM @10 t ha-1 along with inorganic Nitrogen (N and Potassium oxide (K2O @ 50 kg ha-1 produced significantly (P≤0.05 the highest yield of 2.4 t/ha in wheat. The control plot with an indigenous nutrient supply only produced wheat yield of 277 kg ha-1 after 35th year completion of rice-rice-wheat system. A sharp decline in wheat yields was noted in minus N, phosphorus (P, Potassium (K treatments during recent years. Yields were consistently higher in the N:P2O5:K2O and FYM treatments than in treatments, where one or more nutrients were lacking. The application of P2O5 and K2O caused a partial recovery of yield in P and K deficient plots. There was significant (P≤0.05 effect of use of chemical fertilizers and manure on soil properties. The soil analysis data showed an improvement in soil pH (7.8, soil organic matter (4.1%, total N content (0.16%, available P (503.5 kg P2O5 ha-1 and exchangeable K (137.5 kg K2O ha-1 in FYM applied treatments over all other treatments. The findings showed that the productivity of the wheat can be increased and sustained by improving nutrient through the integrated use of organic and inorganic manures in long term.

Streptomyces roietensis sp. nov., an endophytic actinobacterium isolated from the surface-sterilized stem of jasmine rice, Oryza sativa KDML 105.

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Kaewkla, Onuma; Franco, Christopher Milton Mathew

2017-11-01

An endophytic actinobacterium, strain WES2 T , was isolated from the stem of a jasmine rice plant collected from a paddy field in Thung Gura Rong Hai, Roi Et province, Thailand. As a result of a polyphasic study, this strain was identified as representing a novel member of the genus Streptomyces. This strain was a Gram-stain-positive, aerobic actinobacterium with well-developed substrate mycelia and forming chains of looped spores. The closest phylogenetic relations, which shared the highest 16S rRNA gene sequence similarity, were Streptomyces nogalater JCM 4799 T and Streptomyces lavenduligriseus NRRL-ISP 5487 T at 99.1 and 99.0 %, respectively. Chemotaxonomic data, including major fatty acids, cell wall components and major menaquinones, confirmed the affiliation of WES2 T to the genus Streptomyces. The data from the phylogenetic analysis, including physiological and biochemical studies and DNA-DNA hybridization, revealed the genotypic and phenotypic differentiation of WES2 T from the most closely related species with validly published names. The name proposed for the novel species is Streptomycesroietensis sp. nov. The type strain is WES2 T (=DSM 101729=NRRL B-65344).

Comparison of total phenolic content, scavenging activity and HPLC-ESI-MS/MS profiles of both young and mature leaves and stems of Andrographis paniculata.

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Chua, Lee Suan; Yap, Ken Choy; Jaganath, Indu Bala

2013-12-01

The total phenolic content and radical scavenging activity of Andrographis paniculata has been investigated to estimate the amount of phenolic compounds and diterpene lactones, respectively in the plant extracts. The stem extracts exhibited higher total phenolic content and scavenging activity than those of the leaf extracts from both young and mature plants. A range of 19.6-47.8 mg extract of A. paniculata from different parts of the plant is equivalent to the scavenging activity exhibited by one mg of standard Trolox. HPLC-ESI-MS/MS was also used to identify simultaneously the phytochemicals from the leaves and stems of both young and mature plant samples. Of the identified compounds, seven of the sixteen diterpene lactones, three of the six flavonoids, five of the six phenolic acids and two cyclic acids are reported here for the first time for this species. Multivariate statistical approaches such as Hierarchiral Component Analysis (HCA) and Principle Component Analysis (PCA) have clustered the plant extracts into the leaf and stem groups, regardless of plant age. Further classification based on the phytochemical profiles revealed that mostly phenolic acids and flavonoids were from the young leaf extracts, and diterpenoids and their glycosides from the mature leaf extracts. However, the phytochemical profiles for the stems of both young and mature plants were not significantly different as presented in the dendrogram of HCA and the score plot of PCA. The marker for mature plants might be the m/z 557 ion (dihydroxyl dimethyl 19-[(beta-D-glucopyranosyl)oxy]-19-oxo-ent-labda-8(17),13-dien-16,15-olide), whereas the m/z 521 ion (propyl neoandrographolide) could be the marker for leaf extracts.

CHR729 Is a CHD3 Protein That Controls Seedling Development in Rice.

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Ma, Xiaoding; Ma, Jian; Zhai, Honghong; Xin, Peiyong; Chu, Jinfang; Qiao, Yongli; Han, Longzhi

2015-01-01

CHD3 is one of the chromatin-remodeling factors that contribute to controlling the expression of genes associated with plant development. Loss-of-function mutants display morphological and growth defects. However, the molecular mechanisms underlying CHD3 regulation of plant development remain unclear. In this study, a rice CHD3 protein, CHR729, was identified. The corresponding mutant line (t483) exhibited late seed germination, low germination rate, dwarfism, low tiller number, root growth inhibition, adaxial albino leaves, and short and narrow leaves. CHR729 encoded a nuclear protein and was expressed in almost all organs. RNA-sequencing analysis showed that several plant hormone-related genes were up- or down-regulated in t483 compared to wild type. In particular, expression of the gibberellin synthetase gibberellin 20 oxidase 4 gene was elevated in the mutant. Endogenous gibberellin assays demonstrated that the content of bioactive GA3 was reduced in t483 compared to wild type. Moreover, the seedling dwarfism, late seed germination, and short root length phenotypes of t483 were partially rescued by treatment with exogenous GA3. These results suggest that the rice CHD3 protein CHR729 plays an important role in many aspects of seedling development and controls this development via the gibberellin pathway.

CHR729 Is a CHD3 Protein That Controls Seedling Development in Rice.

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Xiaoding Ma

Full Text Available CHD3 is one of the chromatin-remodeling factors that contribute to controlling the expression of genes associated with plant development. Loss-of-function mutants display morphological and growth defects. However, the molecular mechanisms underlying CHD3 regulation of plant development remain unclear. In this study, a rice CHD3 protein, CHR729, was identified. The corresponding mutant line (t483 exhibited late seed germination, low germination rate, dwarfism, low tiller number, root growth inhibition, adaxial albino leaves, and short and narrow leaves. CHR729 encoded a nuclear protein and was expressed in almost all organs. RNA-sequencing analysis showed that several plant hormone-related genes were up- or down-regulated in t483 compared to wild type. In particular, expression of the gibberellin synthetase gibberellin 20 oxidase 4 gene was elevated in the mutant. Endogenous gibberellin assays demonstrated that the content of bioactive GA3 was reduced in t483 compared to wild type. Moreover, the seedling dwarfism, late seed germination, and short root length phenotypes of t483 were partially rescued by treatment with exogenous GA3. These results suggest that the rice CHD3 protein CHR729 plays an important role in many aspects of seedling development and controls this development via the gibberellin pathway.

Variation in essential oil composition within individual leaves of sweet basil (Ocimum basilicum L.) is more affected by leaf position than by leaf age.

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Fischer, Ravit; Nitzan, Nadav; Chaimovitsh, David; Rubin, Baruch; Dudai, Nativ

2011-05-11

The aroma in sweet basil is a factor affecting the commercial value of the crop. In previous studies leaf age was considered to be a factor that influences the composition of essential oil (EO). In this study it was hypothesized that a single observation of the EO content in leaves from different positions on the main stem (young vs old) could predict the developmental changes in the plant during its life cycle. Plants harvested at week 16 demonstrated an exponential increase (R(2) = 0.92) in EO concentration in leaves on the main stem and lateral shoots, indicating higher EO concentrations in younger than in older leaves. Eugenol and methyleugenol predominated (28-77%) in the extract. Eugenol levels were higher in younger leaves (∼53%), and methyl-eugenol levels predominated in older leaves (∼68%). Linalool was lower in mature leaves than in younger leaves. This suggested that eugenol converted into methyleugenol and linalool decreased as leaf mature. However, in weekly monitored plants, the levels of these compounds in the EO had limited variation in the maturing leaf regardless of its position on the stem. This proposed that the EO composition in an individual leaf is mostly affected by the leaf position on the stem and not by its maturation process. Because leaf position is related to plant development, it is probable that the plant's physiological age at the time of leaf formation from the primordial tissue is the factor affecting the EO composition. It was concluded that interpretation of scientific observations should be carried out with caution and that hypotheses should be tested utilizing multifaceted approaches.

Deciphering the factors associated with the colonization of rice plants by cyanobacteria.

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Bidyarani, Ngangom; Prasanna, Radha; Chawla, Gautam; Babu, Santosh; Singh, Rajendra

2015-04-01

Cyanobacteria-rice plant interactions were analyzed using a hydroponics experiment. The activity of plant defense and pathogenesis-related enzymes, scanning electron microscopy, growth, nitrogen fixation (measured as ARA), and DNA fingerprinting assays proved useful in illustrating the nature of associations of cyanobacteria with rice plants. Microscopic analyses revealed the presence of short filaments and coiled masses of filaments of cyanobacteria near the epidermis and cortex of roots and shoot tissues. Among the six cyanobacterial strains employed, Calothrix sp. (RPC1), Anabaena laxa (RPAN8), and Anabaena azollae (C16) were the best performing strains, in terms of colonization in roots and stem. These strains also enhanced nitrogen fixation and stimulated the activity of plant defense/cell wall-degrading enzymes. A significantly high correlation was also recorded between the elicited plant enzymes, growth, and ARA. DNA fingerprinting using highly iterated palindromic sequences (HIP-TG) further helped in proving the establishment of inoculated organisms in the roots/shoots of rice plants. This study illustrated that the colonization of cyanobacteria in the plant tissues is facilitated by increased elicitation of plant enzymes, leading to improved plant growth, nutrient mobilization, and enhanced plant fitness. Such strains can be promising candidates for developing "cyanobacteria colonized-nitrogen-fixing rice plants" in the future. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of White Rice, Brown Rice and Germinated Brown Rice on Antioxidant Status of Type 2 Diabetic Rats

OpenAIRE

Imam, Mustapha Umar; Musa, Siti Nor Asma; Azmi, Nur Hanisah; Ismail, Maznah

2012-01-01

Oxidative stress is implicated in the pathogenesis of diabetic complications, and can be increased by diet like white rice (WR). Though brown rice (BR) and germinated brown rice (GBR) have high antioxidant potentials as a result of their bioactive compounds, reports of their effects on oxidative stress-related conditions such as type 2 diabetes are lacking. We hypothesized therefore that if BR and GBR were to improve antioxidant status, they would be better for rice consuming populations inst...