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Sample records for rice cutgrass grown

  1. DITCH PLANT PRODUCTIVITY UNDER VARIABLE FLOODING: A STUDY OF RICE CUTGRASS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetated drainages are an effective method for removal of pollutants associated with agricultural runoff. Leersia oryzoides (Rice Cutgrass), a plant common to agricultural ditches, may be particularly effective in the remediation; however, the responses of L. oryzoides to flooding are undocumented...

  2. Nutrient and growth responses of Leersia oryzoides, rice cutgrass, to varying degrees of soil saturation and water nitrogen concentration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leersia oryzoides (rice cutgrass) is an obligate wetland plant common to agricultural ditches. The objective of this greenhouse study was to quantify the allocation of nutrients and biomass to different plant components exposed to various soil moisture and aqueous N input regimes. Plants in the con...

  3. Macronutrient (N,P,K) and redoximorphic metal (Fe,Mn) allocation in Leersia oryzoides (rice cutgrass) grown under different flood regimes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetated drainages are an effective method for removal of pollutants associated with agricultural runoff. Leersia oryzoides, a plant common to agricultural ditches, may be particularly effective in remediation; however, research characterizing responses of L. oryzoides to flooding are limited. Soil...

  4. Mechanisms controlling arsenic uptake in rice grown in mining impacted regions in South China.

    PubMed

    Li, Junhui; Dong, Fei; Lu, Ying; Yan, Qiuyan; Shim, Hojae

    2014-01-01

    Foods produced on soils impacted by Pb-Zn mining activities are a potential health risk due to plant uptake of the arsenic (As) associated with such mining. A field survey was undertaken in two Pb-Zn mining-impacted paddy fields in Guangdong Province, China to assess As accumulation and translocation, as well as other factors influencing As in twelve commonly grown rice cultivars. The results showed that grain As concentrations in all the surveyed rice failed national food standards, irrespective of As speciation. Among the 12 rice cultivars, "SY-89" and "DY-162" had the least As in rice grain. No significant difference for As concentration in grain was observed between the rice grown in the two areas that differed significantly for soil As levels, suggesting that the amount of As contamination in the soil is not necessarily the overriding factor controlling the As content in the rice grain. The iron and manganese plaque on the root surface curtailed As accumulation in rice roots. Based on our results, the accumulation of As within rice plants was strongly associated with such soil properties such as silicon, phosphorus, organic matter, pH, and clay content. Understanding the factors and mechanisms controlling As uptake is important to develop mitigation measures that can reduce the amount of As accumulated in rice grains produced on contaminated soils. PMID:25251438

  5. Mechanisms Controlling Arsenic Uptake in Rice Grown in Mining Impacted Regions in South China

    PubMed Central

    Lu, Ying; Yan, Qiuyan; Shim, Hojae

    2014-01-01

    Foods produced on soils impacted by Pb-Zn mining activities are a potential health risk due to plant uptake of the arsenic (As) associated with such mining. A field survey was undertaken in two Pb-Zn mining-impacted paddy fields in Guangdong Province, China to assess As accumulation and translocation, as well as other factors influencing As in twelve commonly grown rice cultivars. The results showed that grain As concentrations in all the surveyed rice failed national food standards, irrespective of As speciation. Among the 12 rice cultivars, “SY-89” and “DY-162” had the least As in rice grain. No significant difference for As concentration in grain was observed between the rice grown in the two areas that differed significantly for soil As levels, suggesting that the amount of As contamination in the soil is not necessarily the overriding factor controlling the As content in the rice grain. The iron and manganese plaque on the root surface curtailed As accumulation in rice roots. Based on our results, the accumulation of As within rice plants was strongly associated with such soil properties such as silicon, phosphorus, organic matter, pH, and clay content. Understanding the factors and mechanisms controlling As uptake is important to develop mitigation measures that can reduce the amount of As accumulated in rice grains produced on contaminated soils. PMID:25251438

  6. Mycotoxin Contamination of Rice Grown in the Southern USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1. Background Rice is widely regarded as unusually resistant to mycotoxin contamination, despite having kernels that provide an exceptionally favorable medium for fungal culture and mycotoxin production. We are interested in learning why rice is mycotoxin resistant, and if any of the resistance mech...

  7. Arsenic speciation in Australian-grown and imported rice on sale in Australia: implications for human health risk.

    PubMed

    Rahman, M Azizur; Rahman, Mohammad Mahmudur; Reichman, Suzie M; Lim, Richard P; Naidu, Ravi

    2014-06-25

    Rice is an important route of arsenic (As) exposure to humans, especially populations with rice-based diets. Human health risk of As varies greatly with rice variety and country of origin. The purpose of the present study was to determine total and speciated As in Australian-grown and imported rice on sale in Australia to assess their health risk to consumers. The total As (tAs) concentrations in Australian-grown organic brown, medium grain brown, and organic white rice were 438±23, 287±03, and 283±18 μg kg(-1) dry weight (d wt), respectively. In Bangladeshi, Indian, Pakistani, and Thai rice imported and on sale in Australia, tAs concentrations were 56±05, 92±10, 82±06 and 172±24 μg kg(-1), respectively. Asian rice contained mainly inorganic As (iAs; 86-99%), whereas 18-26% of the tAs in Australian-grown rice was dimethylarsinic acid (DMA). Relatively higher concentrations of tAs in Australian-grown rice than that in imported rice of Asian origin suggest that Australian-grown rice may be a health risk for the consumers. It was estimated that Australian-grown organic brown rice can contribute up to 98% of the FAO/WHO recommended maximum tolerable daily intake limit of iAs (2.1 μg kg(-1) body wt day(-1)) for Asian immigrants. However, other Australian consumers including European immigrants are unlikely to be at risk to As from rice diets due to their lower rice consumption rates than that of Asian immigrants. The risk assessment showed that imported rice on sale in Australia was likely to pose a lower health risk to consumers than Australian-grown rice. PMID:24892387

  8. Genomic Analysis of Xanthomonas oryzae Isolates from Rice Grown in the United States Reveals Substantial Divergence from Known X. oryzae Pathovars ▿ †

    PubMed Central

    Triplett, L. R.; Hamilton, J. P.; Buell, C. R.; Tisserat, N. A.; Verdier, V.; Zink, F.; Leach, J. E.

    2011-01-01

    The species Xanthomonas oryzae is comprised of two designated pathovars, both of which cause economically significant diseases of rice in Asia and Africa. Although X. oryzae is not considered endemic in the United States, an X. oryzae-like bacterium was isolated from U.S. rice and southern cutgrass in the late 1980s. The U.S. strains were weakly pathogenic and genetically distinct from characterized X. oryzae pathovars. In the current study, a draft genome sequence from two U.S. Xanthomonas strains revealed that the U.S. strains form a novel clade within the X. oryzae species, distinct from all strains known to cause significant yield loss. Comparative genome analysis revealed several putative gene clusters specific to the U.S. strains and supported previous reports that the U.S. strains lack transcriptional activator-like (TAL) effectors. In addition to phylogenetic and comparative analyses, the genome sequence was used for designing robust U.S. strain-specific primers, demonstrating the usefulness of a draft genome sequence in the rapid development of diagnostic tools. PMID:21515727

  9. Growth, yield and elemental status of rice (Oryza sativa) grown in fly ash amended soils.

    PubMed

    Mishra, Mamata; Sahu, Rajani K; Padhy, Rabindra N

    2007-03-01

    Fly ash (FA) from coal in Orissa (India) was used for amending soil at levels equivalent to 0, 1, 2.5, 5, 10 and 15 metric tons per ha in which, rice was grown and elemental residues of amended soil and plant parts were enumerated. FA amendments caused significant improvement in soil quality and germination percentage of rice seeds. Growth (shoot length, leaf area and pigment composition) and yield (panicle length, seeds per panicle, seed weight and yield per plant) of rice increased with an increase in FA amendments. Catalase and peroxidase activities of young leaves increased initially in plants cultivated at lower FA levels but declined sharply at higher FA levels while the protein content of seeds improved at higher FA levels. Sodium content of rice-roots did not change with FA amendments but the contents of K, P, Mn, Ni, Co, Pb, Zn, Cu, Cr, and Cd showed a progressive increase. Seeds of plants grown in FA amended soils accumulated Cu, Pb, Cr and Cd in amounts below allowable limits. Based on the data obtained we found that flooded-rice soil amended at 10 metric tons FA per ha level of FA not only improved the physical properties of the soil but also contributed to better growth and yield of rice. PMID:17253160

  10. Phylogeny and functions of bacterial communities associated with field-grown rice shoots.

    PubMed

    Okubo, Takashi; Ikeda, Seishi; Sasaki, Kazuhiro; Ohshima, Kenshiro; Hattori, Masahira; Sato, Tadashi; Minamisawa, Kiwamu

    2014-09-17

    Metagenomic analysis was applied to bacterial communities associated with the shoots of two field-grown rice cultivars, Nipponbare and Kasalath. In both cultivars, shoot microbiomes were dominated by Alphaproteobacteria (51-52%), Actinobacteria (11-15%), Gammaproteobacteria (9-10%), and Betaproteobacteria (4-10%). Compared with other rice microbiomes (root, rhizosphere, and phyllosphere) in public databases, the shoot microbiomes harbored abundant genes for C1 compound metabolism and 1-aminocyclopropane-1-carboxylate catabolism, but fewer genes for indole-3-acetic acid production and nitrogen fixation. Salicylate hydroxylase was detected in all microbiomes, except the rhizosphere. These genomic features facilitate understanding of plant-microbe interactions and biogeochemical metabolism in rice shoots. PMID:25130883

  11. Accumulation of mercury in rice grain and cabbage grown on representative Chinese soils*

    PubMed Central

    Liu, Chun-fa; Wu, Cheng-xian; Rafiq, Muhammad T.; Aziz, Rukhsanda; Hou, Dan-di; Ding, Zhe-li; Lin, Zi-wen; Lou, Lin-jun; Feng, Yuan-yuan; Li, Ting-qiang; Yang, Xiao-e

    2013-01-01

    A pot culture experiment was carried out to investigate the accumulation properties of mercury (Hg) in rice grain and cabbage grown in seven soil types (Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols) spiked with different concentrations of Hg (CK, 0.25, 0.50, 1.00, 2.00, and 4.00 mg/kg). The results of this study showed that Hg accumulation of plants was significantly affected by soil types. Hg concentration in both rice grain and cabbage increased with soil Hg concentrations, but this increase differed among the seven soils. The stepwise multiple regression analysis showed that pH, Mn(II), particle size distribution, and cation exchange capacity have a close relationship with Hg accumulation in plants, which suggested that physicochemical characteristics of soils can affect the Hg accumulation in rice grain and cabbage. Critical Hg concentrations in seven soils were identified for rice grain and cabbage based on the maximum safe level for daily intake of Hg, dietary habits of the population, and Hg accumulation in plants grown in different soil types. Soil Hg limits for rice grain in Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols were 1.10, 2.00, 2.60, 2.78, 1.53, 0.63, and 2.17 mg/kg, respectively, and critical soil Hg levels for cabbage are 0.27, 1.35, 1.80, 1.70, 0.69, 1.68, and 2.60 mg/kg, respectively. PMID:24302714

  12. Comparison between rice husk ash grown in different regions for stabilizing fly ash from a solid waste incinerator.

    PubMed

    Benassi, L; Bosio, A; Dalipi, R; Borgese, L; Rodella, N; Pasquali, M; Depero, L E; Bergese, P; Bontempi, E

    2015-08-15

    The Stabilization of heavy metals from municipal solid waste incineration (MSWI) fly ash by rice husk ash (RHA) is under intense study as an effective strategy to recover and reuse industrial and agricultural waste together. We compare the metal entrapment performances of RHA from different Asian rice sources – namely from Japonica rice grown in Italy and Indica rice grown in India – Physicochemical and morphological characterization of the final stabilized material show that the same thermal treatment may result in marked structural differences in the silica contained in the two RHA. Remarkably, one of them displays a crystalline silica content, although obtained by a thermal treatment below 800 °C. We also find that the presence of an alkali metal ion (potassium) in the rice husk plays a crucial role in the attainment of the final silica phase. These physicochemical differences are mirrored by different stabilization yields by the two RHA. PMID:26063517

  13. DITCH PLANT PRODUCTIVITY UNDER VARIABLE FLOODING: A STUDY OF RICE CUTGRASS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetated drainages are an effective method for removal of pollutants associated with agricultural runoff. Leersia oryzoides, a plant common to agricultural ditches, may be particularly effective in remediation; however, the responses of L. oryzoides to flooding are undocumented. The objective of ...

  14. Proteomic changes in rice leaves grown under open field high temperature stress conditions.

    PubMed

    Das, Smruti; Krishnan, P; Mishra, Vagish; Kumar, Ritesh; Ramakrishnan, B; Singh, N K

    2015-11-01

    The interactive effect of temperature with other climatic and soil factors has profound influences on the growth and development of rice. The responses of rice to high temperatures under field conditions are more important than those under the controlled conditions. To understand the genes associated with high temperature stress response in general and tolerance in particular, the expression of all those genes associated with adaptation and tolerance in rice requires proteomic analysis. High temperature stress-tolerant cv. N22 was subjected to 28/18 °C (control) and 42/32 °C (high temperature stress) at flowering stage. The plants were grown in the field under the free air temperature increment condition. The proteomic changes in rice leaves due to high temperature stress were discussed. The proteomes of leaves had about 3000 protein spots, reproducibly detected on 2-dimensional electrophoretic gels with 573 proteins differentially expressed between the control and the high temperature treatments. Putative physiological functions suggested five categories such as growth (15.4%), heat shock proteins (7.7%), regulatory proteins (26.9%), redox homeostasis proteins (11.5%) and energy and metabolism (38.5%) related proteins. The results of the present study suggest that cv. N22, an agronomically recognized temperature tolerant rice cultivar copes with high temperature stress in a complex manner. Several functional proteins play important roles in its responses. The predicted climate change events necessitate more studies using this cultivar under different simulated ecological conditions to identify proteomic changes and the associated genes to be used as biomarkers and to gain a better understanding on the biochemical pathways involved in tolerance. PMID:26323334

  15. Arsenic accumulation and speciation in rice grains influenced by arsenic phytotoxicity and rice genotypes grown in arsenic-elevated paddy soils.

    PubMed

    Syu, Chien-Hui; Huang, Chia-Chen; Jiang, Pei-Yu; Lee, Chia-Hsing; Lee, Dar-Yuan

    2015-04-01

    Rice consumption is a major route of As exposure to human for the population of worldwide. This study investigates the effect of phytotoxicity and rice genotypes on the content and speciation of As in rice grains grown in different levels of As-elevated paddy soils from Taiwan. Three levels of As-elevated soils and six rice genotypes commonly planted in Taiwan were used for this study. The results indicate that As contents in grains of rice is not proportional to soil As concentrations and they were equal or higher in indica genotypes than japonica genotypes used in this study. It was also found that the As phytotoxicity not only reducing the grain yields but also the As concentrations in grain of rice. The predominant As species found in rice grains were dimethylarsinic acid (DMA) and arsenite. The concentrations of DMA increased with total As concentrations, wherggeas the arsenite remained in a narrow range from 0.1 to 0.3 mg kg(-1). Because of the lower toxicity of DMA than inorganic As species, the health risks may not be increased through consumption of rice even when total As content in the grains is increased. PMID:25577320

  16. Effect of biochars and microorganisms on cadmium accumulation in rice grains grown in Cd-contaminated soil.

    PubMed

    Suksabye, Parinda; Pimthong, Apinya; Dhurakit, Prapai; Mekvichitsaeng, Phenjun; Thiravetyan, Paitip

    2016-01-01

    Cadmium (Cd) contaminated in rice grains is a serious problem because most Asians consume rice on a daily basis. Rice grown in Cd-contaminated soil normally did not have high concentration of Cd. However, soil samples used in this study had high concentrations of Cd. The purpose of this study was to clearly see the effects of biochar and microorganism addition in rice growing in Cd-contaminated soil. The initial Cd concentration in Cd-contaminated soil used in this study was about 650 mg kg(-1). Cadmium concentration in rice plants grown in Cd-contaminated soil with the addition of 1% (w/w) different biochars such as sawdust fly ash (SDFA), bagasse fly ash (BGFA), and rice husk ash (RHA) was investigated. The results showed that SDFA was the best biochar in terms of reducing cadmium accumulation in rice grains when compared to BGFA and RHA under the same conditions. In addition, rice plants grown in Cd-contaminated soil with the addition of various nonpathogenic microorganisms, such as Pseudomonas aeruginosa, Bacillus subtilis, and Beauveria bassiana were also studied. The results showed that the addition of 2% (v/v) microorganisms can reduce Cd accumulation in grains. It was found that grains obtained from Cd-contaminated soil with the addition of P. aeruginosa had the lowest cadmium concentration compared to the ones from soil amended with other strains. This was due to the fact that P. aeruginosa adsorbed more Cd itself into its cells than other strains. The rice plants grown in Cd-contaminated soil with the addition of biochars and microorganisms were also compared. The results showed that adding 2% (v/v) microorganisms seemed to reduce Cd accumulation in rice grains better than adding 1% (w/w) biochars. In addition, the amounts of calcium and magnesium in rice grains and the dry weight of plant in Cd-contaminated soil amended with P. aeruginosa were the highest in comparison to other microorganisms, biochars, and the soil without any amendments (Cd

  17. Arsenic speciation in locally grown rice grains from Hunan Province, China: Spatial distribution and potential health risk.

    PubMed

    Ma, Li; Wang, Lin; Jia, Yuyu; Yang, Zhaoguang

    2016-07-01

    Arsenic contaminations have been evaluated in rice grains from Hunan Province, China. Forty-three locally grown rice samples were collected from 40 counties. Arsenic species including As(III), As(V), MMA and DMA were separated and determined by HPLC-ICP-MS method. The mean concentration of total arsenic in rice samples was 129.4±49.2μg/kg, lower than the Chinese maximum contaminant levels of inorganic arsenic in rice (200μg/kg). The dominant species detected in rice samples was As(III), following DMA, As(V) and MMA. The Pearson's correlation analysis indicated significant positive relationships between As(III) and total arsenic (r=0.939, p<0.01), and DMA and total arsenic (r=0.761, p<0.01). However, the percentage of As(III) decreased with the total arsenic concentration in rice (r=-0.515, p<0.01). Spatial distribution map of total arsenic concentration in rice samples from Hunan Province was obtained using kriging interpolation. High levels of total arsenic in rice grains were observed in south and east regions associated with mining activities and urbanization process. The cancer risk and hazard quotient were employed to estimate the potential human health risk. The results suggested great carcinogenic risk and high potential non-carcinogenic risk to people consuming local rice in Hunan Province. PMID:27016689

  18. Soil to rice transfer factors for (226)Ra, (228)Ra, (210)Pb, (40)K and (137)Cs: a study on rice grown in India.

    PubMed

    Karunakara, N; Rao, Chetan; Ujwal, P; Yashodhara, I; Kumara, Sudeep; Ravi, P M

    2013-04-01

    India is the second largest producer of rice (Oryza sativa L.) in the world and rice is an essential component of the diet for a majority of the population in India. However, detailed studies aimed at the evaluation of radionuclide transfer factors (F(v)) for the rice grown in India are almost non-existent. This paper presents the soil to rice transfer factors for natural ((226)Ra, (228)Ra, (40)K, and (210)Pb) and artificial ((137)Cs) radionuclides for rice grown in natural field conditions on the West Coast of India. A rice field was developed very close to the Kaiga nuclear power plant and the water required for this field was drawn from the cooling water discharge canal of the power plant. For a comparative study of the radionuclide transfer factors, rice samples were also collected from the rice fields of nearby villages. The study showed that the (226)Ra and (228)Ra activity concentrations were below detection levels in different organs of the rice plant. The soil to un-hulled rice grain (40)K transfer factor varied in the range of 6.5 × 10(-1) to 2.9 with a mean of 0.15 × 10(1), and of (210)Pb varied in the range of <1.2 × 10(-2) to 8.1 × 10(-1) with a mean of 1.4 × 10(-1), and of (137)Cs varied in the range of 6.6 × 10(-2) to 3.4 × 10(-1) with a mean of 2.1 × 10(-1). The mean values of un-hulled grain to white rice processing retention factors (F(r)) were 0.12 for (40)K, 0.03 for (210)Pb, and 0.14 for (137)Cs. Using these processing retention factors, the soil to white rice transfer factors were estimated and these were found to have mean values of 1.8 × 10(-1), 4.2 × 10(-3), and 3.0 × 10(-2) for (40)K, (210)Pb, and (137)Cs, respectively. The study has shown that the transfer of (40)K was higher for above the ground organs than for the root, but (210)Pb and (137)Cs were retained in the root and their transfer to above the ground organs of the rice plant is significantly lower. PMID:23266913

  19. Variation of grain Cd and Zn concentrations of 110 hybrid rice cultivars grown in a low-Cd paddy soil.

    PubMed

    Shi, Jing; Li, Lianqing; Pan, Genxing

    2009-01-01

    Enhanced Cd uptake and Zn depletion in rice grains and high potential for food Cd exposure by the high-yielding hybrid cultivars of China had been addressed. A field experiment was conducted in 2006 to determine the difference in grain Cd and Zn between cultivars. Total 110 cultivars including super rice and common hybrid rice cultivars were grown on a single paddy soil (Entic Haplaquept) with a neutral reaction and low total Cd content. Grain Cd and Zn concentrations were determined with graphite atomic adsorption spectrophotometer (GFAAS) and flame atomic adsorption spectrophotometer (AAS) respectively. Wide variation of Cd content in grain was found in a range of 0.004-0.057 mg/kg, while the Zn content in a range of 10.25-30.06 mg/kg among the cultivars. Higher Cd but lower Zn concentration in grains of super rice cultivars was observed compared to the common hybrid ones. A highly significant positive linear correlation of grain Cd/Zn with grain Cd was found for super rice and common hybrid cultivars, meanwhile much higher slope for these hybrid cultivars than the reported non-hybrid cultivars was also observed. Using the limit value of the Chinese chemical guidelines for foods (MOHC and SSC, 2005), calculated potential risk of food Cd exposure with "Zn hungry" through diet intake was prominent with all the studied 110 hybrid rice cultivars, possessing high potential health problems for rice production in South China using the super rice cultivars. Breeding of genotypes of rice cultivars with low grain Cd and low Cd/Zn ratio is needed for rice production in acidic red soils where Cd bioavailability is prevalently high. PMID:19402417

  20. Growth and yield response of field-grown tropical rice to increasing carbon dioxide and air temperature

    SciTech Connect

    Ziska, L.H.; Namuco, O.; Moya, T.; Quilang, J.

    1997-01-01

    Although the response of rice (Oryza sativa L.) to increasing atmospheric CO{sub 2} concentration and air temperature has been examined at the greenhouse or growth chamber level, no field studies have been conducted under the tropical, irrigated conditions where the bulk of the world`s rice is grown. At the International Rice Research Institute, rice (cv. IR 72) was grown from germination until maturity for the 1994 wet and 1995 dry seasons at three different CO{sub 2} concentrations (ambient, ambient + 200, and ambient + 300 {mu}L L{sup {minus}1}) resulted in a significant increase in total plant biomass (+31%, +40%) and crop yield (+15%, + 27%) compared with the ambient control. The increase in crop yield was associated with an increase in the number of panicles per square meter and a greater percentage of filled spikelets. Simultaneous increases in CO{sub 2} and air temperature did not alter the biomass at maturity (relative to elevated CO{sub 2} alone), but plant development was accelerated at the higher growth temperature regardless of CO{sub 2} concentration. Grain yield, however, became insensitive to CO{sub 2} concentration at the higher growth temperature. Increasing both CO{sub 2} and air temperature also reduced grain quality (e.g., protein content). The combination of CO{sub 2} and temperature effects suggests that, in warmer regions (i.e., >34{degrees}C) where rice is grown, quantitative and qualitative changes in rice supply are possible if both CO{sub 2} and air temperature continue to increase. 24 refs., 6 figs., 4 tabs.

  1. Iron and zinc isotope fractionation during uptake and translocation in rice (Oryza sativa) grown in oxic and anoxic soils

    NASA Astrophysics Data System (ADS)

    Arnold, Tim; Markovic, Tamara; Kirk, Guy J. D.; Schönbächler, Maria; Rehkämper, Mark; Zhao, Fangjie J.; Weiss, Dominik J.

    2015-11-01

    Stable isotope fractionation is emerging quickly as a powerful novel technique to study metal uptake and translocation in plants. Fundamental to this development is a thorough understanding of the processes that lead to isotope fractionation under differing environmental conditions. In this study, we investigated Zn and Fe isotope fractionation in rice grown to maturity in anaerobic and aerobic soils under greenhouse conditions. The overall Zn isotope fractionation between the soil and above ground plant material was negligible in aerobic soil but significant in anaerobic soil with isotopically lighter Zn in the rice plant. The observed range of fractionation is in line with previously determined fractionations of Zn in rice grown in hydroponic solutions and submerged soils and emphasizes the effect of taking up different chemical forms of Zn, most likely free and organically complexed Zn. The Zn in the grain was isotopically lighter than in the rest of the above ground plant in rice grown in aerobic and anaerobic soils alike. This suggests that in the course of the grain loading and during the translocation within the plant important biochemical and/or biophysical processes occur. The isotope fractionation observed in the grains would be consistent with an unidirectional controlled transport from shoot to grain with a fractionation factor of α ≈ 0.9994. Iron isotopes showed an isotopic lighter signature in shoot and grain compared to the bulk soil or the leachate in aerobic and anaerobic soils alike. The negative direction of isotopic fractionation is consistent with possible changes in the redox state of Fe occurring during the uptake and translocation processes. The isotope fractionation pattern between shoots and grain material are different for Zn and Fe which finally suggests that different mechanisms operate during translocation and grain-loading in rice for these two key micronutrients.

  2. Leaf photosynthesis and Rubisco activity and kinetics of soybean, peanut, and rice grown under elevated atmospheric CO2, supraoptimal air temperature, and soil water deficit.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean, peanut and rice were grown at 350 and 700 (high) ppm CO2, and under varying day/night temperature (T) regimes ranging from 28/18 to 48/38C for soybean and peanut, or soil water deficit for rice, (a) to determine the interactive impacts of high CO2-high T, or high CO2-drought, on midday leaf...

  3. Suppression of Hydroxycinnamate Network Formation in Cell Walls of Rice Shoots Grown under Microgravity Conditions in Space.

    PubMed

    Wakabayashi, Kazuyuki; Soga, Kouichi; Hoson, Takayuki; Kotake, Toshihisa; Yamazaki, Takashi; Higashibata, Akira; Ishioka, Noriaki; Shimazu, Toru; Fukui, Keiji; Osada, Ikuko; Kasahara, Haruo; Kamada, Motoshi

    2015-01-01

    Network structures created by hydroxycinnamate cross-links within the cell wall architecture of gramineous plants make the cell wall resistant to the gravitational force of the earth. In this study, the effects of microgravity on the formation of cell wall-bound hydroxycinnamates were examined using etiolated rice shoots simultaneously grown under artificial 1 g and microgravity conditions in the Cell Biology Experiment Facility on the International Space Station. Measurement of the mechanical properties of cell walls showed that shoot cell walls became stiff during the growth period and that microgravity suppressed this stiffening. Amounts of cell wall polysaccharides, cell wall-bound phenolic acids, and lignin in rice shoots increased as the shoot grew. Microgravity did not influence changes in the amounts of cell wall polysaccharides or phenolic acid monomers such as ferulic acid (FA) and p-coumaric acid, but it suppressed increases in diferulic acid (DFA) isomers and lignin. Activities of the enzymes phenylalanine ammonia-lyase (PAL) and cell wall-bound peroxidase (CW-PRX) in shoots also increased as the shoot grew. PAL activity in microgravity-grown shoots was almost comparable to that in artificial 1 g-grown shoots, while CW-PRX activity increased less in microgravity-grown shoots than in artificial 1 g-grown shoots. Furthermore, the increases in expression levels of some class III peroxidase genes were reduced under microgravity conditions. These results suggest that a microgravity environment modifies the expression levels of certain class III peroxidase genes in rice shoots, that the resultant reduction of CW-PRX activity may be involved in suppressing DFA formation and lignin polymerization, and that this suppression may cause a decrease in cross-linkages within the cell wall architecture. The reduction in intra-network structures may contribute to keeping the cell wall loose under microgravity conditions. PMID:26378793

  4. Suppression of Hydroxycinnamate Network Formation in Cell Walls of Rice Shoots Grown under Microgravity Conditions in Space

    PubMed Central

    Wakabayashi, Kazuyuki; Soga, Kouichi; Hoson, Takayuki; Kotake, Toshihisa; Yamazaki, Takashi; Higashibata, Akira; Ishioka, Noriaki; Shimazu, Toru; Fukui, Keiji; Osada, Ikuko; Kasahara, Haruo; Kamada, Motoshi

    2015-01-01

    Network structures created by hydroxycinnamate cross-links within the cell wall architecture of gramineous plants make the cell wall resistant to the gravitational force of the earth. In this study, the effects of microgravity on the formation of cell wall-bound hydroxycinnamates were examined using etiolated rice shoots simultaneously grown under artificial 1 g and microgravity conditions in the Cell Biology Experiment Facility on the International Space Station. Measurement of the mechanical properties of cell walls showed that shoot cell walls became stiff during the growth period and that microgravity suppressed this stiffening. Amounts of cell wall polysaccharides, cell wall-bound phenolic acids, and lignin in rice shoots increased as the shoot grew. Microgravity did not influence changes in the amounts of cell wall polysaccharides or phenolic acid monomers such as ferulic acid (FA) and p-coumaric acid, but it suppressed increases in diferulic acid (DFA) isomers and lignin. Activities of the enzymes phenylalanine ammonia-lyase (PAL) and cell wall-bound peroxidase (CW-PRX) in shoots also increased as the shoot grew. PAL activity in microgravity-grown shoots was almost comparable to that in artificial 1 g-grown shoots, while CW-PRX activity increased less in microgravity-grown shoots than in artificial 1 g-grown shoots. Furthermore, the increases in expression levels of some class III peroxidase genes were reduced under microgravity conditions. These results suggest that a microgravity environment modifies the expression levels of certain class III peroxidase genes in rice shoots, that the resultant reduction of CW-PRX activity may be involved in suppressing DFA formation and lignin polymerization, and that this suppression may cause a decrease in cross-linkages within the cell wall architecture. The reduction in intra-network structures may contribute to keeping the cell wall loose under microgravity conditions. PMID:26378793

  5. Gasified rice hull biochar is a source of phosphorus and potassium for container-grown plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biochar materials have been reported to improve the chemical, physical, and biological properties of mineral soils and soilless substrates. The objective of this research was to determine the effect of gasified rice hull biochar (GRHB) on available nutrients in a container substrate. Two experimen...

  6. Seed physicochemical characteristics of field-grown U.S. weedy red rice biotypes: Contrasts with commercial cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice in the US is an aggressive weed that reduces the yield of rice and contaminates its grain. It is the same species as rice, which provides an opportunity for intercrossing. This genetic similarity complicates the management of red rice in fields and rice mills, but also indicates a potential...

  7. Screening for phosphate solubilizing bacteria inhabiting the rhizoplane of rice grown in acidic soil in Bangladesh.

    PubMed

    Sarkar, Animesh; Islam, Tofazzal; Biswas, Gokul Chandra; Alam, Shohidul; Hossain, Mikail; Talukder, Nur Mohammad

    2012-06-01

    The objectives of the research were to isolate phosphate solubilizing bacteria (PSB) from the rhizoplane of rice (Oryza sativa L.) cv. BRRIdhan 29 cultivated in acidic soils of Tangail in Bangladesh and evaluate their performances in phosphate solubilization in both in vitro and in vivo conditions. A total of 10 bacterial strains were isolated and purified by repeated streak culture on nutrient agar medium. Upon screening, five isolates (OS01, OS03, OS07, OS08 and OS10) showed varying levels of phosphate solubilizing activity in agar plate and broth assays. Among them, the strain OS07 (B1) and two previously isolated PSB strains B2 and B3 were selected for evaluation for their performances in rice alone or in combination of TSP (triple super phosphate: P1) and rock phosphate (P2). Plant height and the number of tillers per plant were significantly increased by all PSB isolates when used in combination with TSP but PSB alone did not influence much on plant height and the number of tillers except B1. The levels of mineral nutrients content in rice plant tissues were generally increased by the application of the PSB in combination with TSP, while the performances of B1 isolate was superior in all aspects to B2 and B3 isolates. PMID:22750780

  8. Uptake of cadmium by rice grown on contaminated soils and its bioavailability/toxicity in human cell lines (Caco-2/HL-7702).

    PubMed

    Aziz, Rukhsanda; Rafiq, Muhammad Tariq; Li, Tingqiang; Liu, Di; He, Zhenli; Stoffella, P J; Sun, Kewang; Xiaoe, Yang

    2015-04-01

    Cadmium (Cd) enters the food chain from polluted soils via contaminated cereals and vegetables; therefore, an understanding of Cd bioaccessibility, bioavailability, and toxicity in humans through rice grain is needed. This study assessed the Cd bioaccessibility, bioavailability, and toxicity to humans from rice grown on Cd-contaminated soils using an in vitro digestion method combined with a Caco-2/HL-7702 cell model. Cadmium bioaccessibility (18.45-30.41%) and bioavailability (4.04-8.62%) were found to be significantly higher in yellow soil (YS) rice than calcareous soil (CS) rice with the corresponding values of 6.89-11.43 and 1.77-2.25%, respectively. Toxicity assays showed an initial toxicity in YS rice at 6 mg kg(-1) Cd, whereas CS rice did not show any significant change due to low Cd concentrations. The acidic soils of Cd-contaminated areas can contribute to a higher dietary intake of Cd. Therefore, it is imperative to monitor Cd concentration in rice to minimize human health risk. PMID:25738308

  9. Assessment of arsenic in Australian grown and imported rice varieties on sale in Australia and potential links with irrigation practises and soil geochemistry.

    PubMed

    Fransisca, Yunnita; Small, Darryl M; Morrison, Paul D; Spencer, Michelle J S; Ball, Andrew S; Jones, Oliver A H

    2015-11-01

    Chronic dietary exposure to arsenic, particularly the inorganic forms (defined as elemental arsenic, predominantly As(3+) and As(5+), and all its inorganic compounds except arsine), is a matter of concern for human health. Ingestion of arsenic usually occurs via contaminated water but recent studies show there is also a risk of exposure from food, particularly Asian rice (Oryza sativa). Australia is a rice growing country, contributing around 2% of the world rice trade, and a large proportion of the population consumes rice regularly. In the present study we investigated concentrations of arsenic in both Australian grown and imported rice on sale in Australia and examined the potential links with irrigation practises and soil geochemistry. The results indicated a wide spread of arsenic levels of 0.09-0.33 mg kg(-1), with Australian grown Arborio and sushi varieties of O. sativa containing the highest mean value of ∼0.22 mg kg(-1). Arsenic levels in all samples were below the 1 mg kg(-1) limit set by Food Standards Australia New Zealand. PMID:25577696

  10. Iodate and iodide effects on iodine uptake and partitioning in rice (Oryza sativa L.) grown in solution culture.

    PubMed

    Mackowiak, C L; Grossl, P R

    1999-01-01

    In the Xinjiang province of western China, conventional methods of iodine (I) supplementation (i.e, goiter pills and iodinated salt) used to mitigate I deficiencies were ineffectual. However, the recent addition of KIO3 to irrigation waters has proven effective. This study was conducted to determine the effects of I form and concentration on rice (Oryza sativa L.) growth, I partitioning within the plant, and ultimately to assist in establishing guidelines for incorporating I into the human food chain. We compared IO3- vs. I- in order to determine how these chemical species differ in their biological effects. Rice was grown in 48 L aerated tubs containing nutrient solution and IO3- or I- at 0, 1, 10, or 100 micromoles concentrations (approximately 0, 0.1, 1, and 10 mg kg-1 I). The IO3- at 1 and 10 micromoles had no effect on biomass yields, and the 100 micromole treatment had a small negative effect. The I- at 10 and 100 micromoles was detrimental to biomass yields. The IO3- treatments had more I partitioning to the roots (56%) on average than did the I- treatments (36%), suggesting differences in uptake or translocation between I forms. The data support the theory that IO3- is electrochemically or biologically reduced to I- prior to plant uptake. None of the treatments provided sufficient I in the seed to meet human dietary requirements. The I concentration found in straw at 100 micromoles IO3- was several times greater than seed, and could provide an indirect source of dietary I via livestock feeding on the straw. PMID:11762382

  11. Characterization of rice (Oryza sativa L.) genotypes on the basis of morpho-physiological and biochemical traits grown under aerobic situation in rainfed ecosystem .

    PubMed

    Kumar, Santosh; Dwivedi, Sharad Kumar; Singh, S S; Kumar, Sanjeev; Sundaram, R K; Shivani; Mall, A K

    2015-07-01

    The objective of the present study was to examine the effect of aerobic situation on yield, physiological and biochemical traits of advanced breeding lines of rice. Experiment was conducted with two set of rice genotypes under two water regimes (aerobic and irrigated), during three consecutive wet seasons 2010-2012. Significant decrease in yield was observed in rice genotypes grown under aerobic situation as compared to the irrigated ones. Promising rice genotypes having the ability to maintain high plant biomass, harvest index, early vegetative vigour, improved physiological and biochemical traits in terms of relative water content (RWC), leaf area index (LAI), total soluble sugar, starch, protien and proline content help to sustain higher grain yield under aerobic situation. The yield gap between aerobic and irrigated rice ranged between 24% to 68%. Grain yield showed positive correlation with harvest index (0.434), test weight (0.647), plant biomass (0.411) and effective tiller numbers (0.473), whereas spikelet sterility was negative associated (-0.380). The current study suggested that promising genotypes viz., IR77298-14-1-2-130-2, IR84899-B-182-3-1-1-2, IR84887-B-157-38-1-1-3 and IR 84899-B-179-1-1-1-2 for aerobic situation, showing yield advantage due to better performance of physiological and biochemical traits, might be adopted in large area of rainfed ecosystem as well as in irrigated areas where water scarcity was a major problem. PMID:26364481

  12. Chromium bioaccumulation in rice grown in contaminated soil and irrigated mine wastewater--a case study at South Kaliapani chromite mine area, Orissa, India.

    PubMed

    Mohanty, Monalisa; Pattnaik, Mousumi Madhusmita; Mishra, Aruna Kumari; Patra, Hemanta Kumar

    2011-01-01

    The level of chromium (Cr) contamination in soils and irrigated mine wastewater at South Kaliapani chromite mine region of Orissa, (India) were investigated. Chromium bioaccumulation in rice plants (Oryza sativa L. cv. Khandagiri) irrigated with Cr+6 contaminated mine wastewater was analyzed along with its attenuation from mine wastewater. The levels of Cr+6 in irrigated mine wastewaters in successive rice grown plots were analyzed on 75 days and 100 days after transplantation of seedlings. Total chromium content in different parts of rice plants and soil samples from different plots was analyzed during harvesting stage (125 days after transplantation). Cr accumulation was significantly high in surface soils (0-20 cm) with a mean value of 11,170 mg kg(-1), but it decreased significantly after the crop harvest. About 70% to 90% reduction of Cr+6 levels was observed in irrigated mine wastewater when passed through successive rice plots. High bio-concentration of Cr in leaves with values ranging from 125-498 mg kg(-1) as compared to stem (25-400 mg kg(-1)) and grain (5-23 mg kg(-1)) was noticed. The reduction of Cr+6 levels is related to plant age, high biomass and area of water passage and was attributed to rhizofiltration technique. PMID:21598771

  13. Photosynthesis is induced in rice plants that associate with arbuscular mycorrhizal fungi and are grown under arsenate and arsenite stress.

    PubMed

    de Andrade, Sara Adrian Lopez; Domingues, Adilson Pereira; Mazzafera, Paulo

    2015-09-01

    The metalloid arsenic (As) increases in agricultural soils because of anthropogenic activities and may have phytotoxic effects depending on the available concentrations. Plant performance can be improved by arbuscular mycorrhiza (AM) association under challenging conditions, such as those caused by excessive soil As levels. In this study, the influence of AM on CO2 assimilation, chlorophyll a fluorescence, SPAD-chlorophyll contents and plant growth was investigated in rice plants exposed to arsenate (AsV) or arsenite (AsIII) and inoculated or not with Rhizophagus irregularis. Under AsV and AsIII exposure, AM rice plants had greater biomass accumulation and relative chlorophyll content, increased water-use efficiency, higher carbon assimilation rate and higher stomatal conductance and transpiration rates than non-AM rice plants did. Chlorophyll a fluorescence analysis revealed significant differences in the response of AM-associated and -non-associated plants to As. Mycorrhization increased the maximum and actual quantum yields of photosystem II and the electron transport rate, maintaining higher values even under As exposure. Apart from the negative effects of AsV and AsIII on the photosynthetic rates and PSII efficiency in rice leaves, taken together, these results indicate that AM is able to sustain higher rice photosynthesis efficiency even under elevated As concentrations, especially when As is present as AsV. PMID:25935603

  14. Abundance of rice root aphid among selected plant species and on plants grown with different soil-surface media

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rice root aphid, Rhopalosiphum rufiabdominalis (Sasaki), is distributed worldwide and colonizes a wide range of plants. However, relatively little is known about the suitability of different host plants, optimal rearing techniques, and the aphid’s impact on plant fitness. To improve understand...

  15. Yield and size of oyster mushroom grown on rice/wheat straw basal substrate supplemented with cotton seed hull.

    PubMed

    Yang, Wenjie; Guo, Fengling; Wan, Zhengjie

    2013-10-01

    Oyster mushroom (Pleurotus ostreatus) was cultivated on rice straw basal substrate, wheat straw basal substrate, cotton seed hull basal substrate, and wheat straw or rice straw supplemented with different proportions (15%, 30%, and 45% in rice straw substrate, 20%, 30%, and 40% in wheat straw substrate) of cotton seed hull to find a cost effective substrate. The effect of autoclaved sterilized and non-sterilized substrate on growth and yield of oyster mushroom was also examined. Results indicated that for both sterilized substrate and non-sterilized substrate, oyster mushroom on rice straw and wheat basal substrate have faster mycelial growth rate, comparatively poor surface mycelial density, shorter total colonization period and days from bag opening to primordia formation, lower yield and biological efficiency, lower mushroom weight, longer stipe length and smaller cap diameter than that on cotton seed hull basal substrate. The addition of cotton seed hull to rice straw and wheat straw substrate slowed spawn running, primordial development and fruit body formation. However, increasing the amount of cotton seed hull can increase the uniformity and white of mycelium, yield and biological efficiency, and increase mushroom weight, enlarge cap diameter and shorten stipe length. Compared to the sterilized substrate, the non-sterilized substrate had comparatively higher mycelial growth rate, shorter total colonization period and days from bag opening to primordia formation. However, the non-sterilized substrate did not gave significantly higher mushroom yield and biological efficiency than the sterilized substrate, but some undesirable characteristics, i.e. smaller mushroom cap diameter and relatively long stipe length. PMID:24235869

  16. Yield and size of oyster mushroom grown on rice/wheat straw basal substrate supplemented with cotton seed hull

    PubMed Central

    Yang, WenJie; Guo, FengLing; Wan, ZhengJie

    2013-01-01

    Oyster mushroom (Pleurotus ostreatus) was cultivated on rice straw basal substrate, wheat straw basal substrate, cotton seed hull basal substrate, and wheat straw or rice straw supplemented with different proportions (15%, 30%, and 45% in rice straw substrate, 20%, 30%, and 40% in wheat straw substrate) of cotton seed hull to find a cost effective substrate. The effect of autoclaved sterilized and non-sterilized substrate on growth and yield of oyster mushroom was also examined. Results indicated that for both sterilized substrate and non-sterilized substrate, oyster mushroom on rice straw and wheat basal substrate have faster mycelial growth rate, comparatively poor surface mycelial density, shorter total colonization period and days from bag opening to primordia formation, lower yield and biological efficiency, lower mushroom weight, longer stipe length and smaller cap diameter than that on cotton seed hull basal substrate. The addition of cotton seed hull to rice straw and wheat straw substrate slowed spawn running, primordial development and fruit body formation. However, increasing the amount of cotton seed hull can increase the uniformity and white of mycelium, yield and biological efficiency, and increase mushroom weight, enlarge cap diameter and shorten stipe length. Compared to the sterilized substrate, the non-sterilized substrate had comparatively higher mycelial growth rate, shorter total colonization period and days from bag opening to primordia formation. However, the non-sterilized substrate did not gave significantly higher mushroom yield and biological efficiency than the sterilized substrate, but some undesirable characteristics, i.e. smaller mushroom cap diameter and relatively long stipe length. PMID:24235869

  17. Arsenic affects mineral nutrients in grains of various Indian rice (Oryza sativa L.) genotypes grown on arsenic-contaminated soils of West Bengal.

    PubMed

    Dwivedi, Sanjay; Tripathi, R D; Srivastava, Sudhakar; Singh, Ragini; Kumar, Amit; Tripathi, Preeti; Dave, Richa; Rai, U N; Chakrabarty, Debasis; Trivedi, P K; Tuli, R; Adhikari, B; Bag, M K

    2010-09-01

    The exposure of paddy fields to arsenic (As) through groundwater irrigation is a serious concern that may not only lead to As accumulation to unacceptable levels but also interfere with mineral nutrients in rice grains. In the present field study, profiling of the mineral nutrients (iron (Fe), phosphorous, zinc, and selenium (Se)) was done in various rice genotypes with respect to As accumulation. A significant genotypic variation was observed in elemental retention on root Fe plaque and their accumulation in various plant parts including grains, specific As uptake (29-167 mg kg(-1) dw), as well as As transfer factor (4-45%). Grains retained the least level of As (0.7-3%) with inorganic As species being the dominant forms, while organic As species, viz., dimethylarsinic acid and monomethylarsonic acid, were non-detectable. In all tested varieties, the level of Se was low (0.05-0.12 mg kg(-1) dw), whereas that of As was high (0.4-1.68 mg kg(-1) dw), considering their safe/recommended daily intake limits, which may not warrant their human consumption. Hence, their utilization may increase the risk of arsenicosis, when grown in As-contaminated areas. PMID:20490609

  18. Soil and water warming accelerates phenology and down-regulation of leaf photosynthesis of rice plants grown under free-air CO2 enrichment (FACE).

    PubMed

    Adachi, Minaco; Hasegawa, Toshihiro; Fukayama, Hiroshi; Tokida, Takeshi; Sakai, Hidemitsu; Matsunami, Toshinori; Nakamura, Hirofumi; Sameshima, Ryoji; Okada, Masumi

    2014-02-01

    To enable prediction of future rice production in a changing climate, we need to understand the interactive effects of temperature and elevated [CO2] (E[CO2]). We therefore examined if the effect of E[CO2] on the light-saturated leaf photosynthetic rate (Asat) was affected by soil and water temperature (NT, normal; ET, elevated) under open-field conditions at the rice free-air CO2 enrichment (FACE) facility in Shizukuishi, Japan, in 2007 and 2008. Season-long E[CO2] (+200 µmol mol(-1)) increased Asat by 26%, when averaged over two years, temperature regimes and growth stages. The effect of ET (+2°C) on Asat was not significant at active tillering and heading, but became negative and significant at mid-grain filling; Asat in E[CO2]-ET was higher than in ambient [CO2] (A[CO2])-NT by only 4%. Photosynthetic down-regulation at E[CO2] also became apparent at mid-grain filling; Asat compared at the same [CO2] in the leaf cuvette was significantly lower in plants grown in E[CO2] than in those grown in A[CO2]. The additive effects of E[CO2] and ET decreased Asat by 23% compared with that of A[CO2]-NT plants. Although total crop nitrogen (N) uptake was increased by ET, N allocation to the leaves and to Rubisco was reduced under ET and E[CO2] at mid-grain filling, which resulted in a significant decrease (32%) in the maximum rate of ribulose-1,5-bisphosphate carboxylation on a leaf area basis. Because the change in N allocation was associated with the accelerated phenology in E[CO2]-ET plants, we conclude that soil and water warming accelerates photosynthetic down-regulation at E[CO2]. PMID:24406632

  19. Soil and Water Warming Accelerates Phenology and Down-Regulation of Leaf Photosynthesis of Rice Plants Grown Under Free-Air CO2 Enrichment (FACE)

    PubMed Central

    Adachi, Minaco; Hasegawa, Toshihiro; Fukayama, Hiroshi; Tokida, Takeshi; Sakai, Hidemitsu; Matsunami, Toshinori; Nakamura, Hirofumi; Sameshima, Ryoji; Okada, Masumi

    2014-01-01

    To enable prediction of future rice production in a changing climate, we need to understand the interactive effects of temperature and elevated [CO2] (E[CO2]). We therefore examined if the effect of E[CO2] on the light-saturated leaf photosynthetic rate (Asat) was affected by soil and water temperature (NT, normal; ET, elevated) under open-field conditions at the rice free-air CO2 enrichment (FACE) facility in Shizukuishi, Japan, in 2007 and 2008. Season-long E[CO2] (+200 µmol mol−1) increased Asat by 26%, when averaged over two years, temperature regimes and growth stages. The effect of ET (+2°C) on Asat was not significant at active tillering and heading, but became negative and significant at mid-grain filling; Asat in E[CO2]–ET was higher than in ambient [CO2] (A[CO2])–NT by only 4%. Photosynthetic down-regulation at E[CO2] also became apparent at mid-grain filling; Asat compared at the same [CO2] in the leaf cuvette was significantly lower in plants grown in E[CO2] than in those grown in A[CO2]. The additive effects of E[CO2] and ET decreased Asat by 23% compared with that of A[CO2]–NT plants. Although total crop nitrogen (N) uptake was increased by ET, N allocation to the leaves and to Rubisco was reduced under ET and E[CO2] at mid-grain filling, which resulted in a significant decrease (32%) in the maximum rate of ribulose-1,5-bisphosphate carboxylation on a leaf area basis. Because the change in N allocation was associated with the accelerated phenology in E[CO2]–ET plants, we conclude that soil and water warming accelerates photosynthetic down-regulation at E[CO2]. PMID:24406632

  20. Deciphering Phosphate Deficiency-Mediated Temporal Effects on Different Root Traits in Rice Grown in a Modified Hydroponic System

    PubMed Central

    Negi, Manisha; Sanagala, Raghavendrarao; Rai, Vandna; Jain, Ajay

    2016-01-01

    Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. PMID:27200025

  1. Deciphering Phosphate Deficiency-Mediated Temporal Effects on Different Root Traits in Rice Grown in a Modified Hydroponic System.

    PubMed

    Negi, Manisha; Sanagala, Raghavendrarao; Rai, Vandna; Jain, Ajay

    2016-01-01

    Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. PMID:27200025

  2. Organic Rice Production: Challenges and Opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The market demand for organically produced rice has grown steadily with the majority of the acreage now being located in Texas and California. A wide range of organic products are marketed including conventional long and medium grain rice, aromatic or scented rice, rice with colored bran, and rice f...

  3. Factors affecting variation in CH4 emission from paddy soils grown with different rice cultivars: A pot experiment

    NASA Astrophysics Data System (ADS)

    Watanabe, Akira; Kimura, Makoto

    1998-08-01

    The growth of rice plants greatly influences CH4 emission from paddy fields through the supply of organic materials such as root exudates and sloughed tissues, the release of oxygen to the root environment, and the transfer of CH4 from the rhizosphere into the atmosphere through the aerenchyma. In the present pot experiments, the effects of the release of water-soluble organic substances from roots, the air space in roots, and the CH4-oxidizing capacity of roots on intervarietal differences in CH4 emission were examined using three Japonica type cultivars (Norin 25, Nipponbare, and Aoinokaze), which differ in morphological properties. The CH4 emission rates varied among the cultivars from mid-July (tillering stage) to the beginning of September (heading stage).Total CH4 emission throughout the rice growth period was largest for Norin 25, followed by Nipponbare, and Aoinokaze. In August, the rate of release of water-soluble organic substances from roots was largest for Norin 25. The air space in roots was also largest in Norin 25 and least in Aoinokaze. The stable carbon isotopic ratios (δ13C) of CH4 in roots were 3-10‰ higher than those in soil in August. The difference in δ13C values of CH4 between roots and soil was largest for Aoinokaze and smallest for Norin 25. In September, the difference in δ13C values of CH4 between roots and soil became small (2-3‰). These findings suggest that the proportion of CH4 oxidation in the rhizosphere was largest in the cultivar which emitted the smallest amount of CH4 and that the proportion became smaller with continued plant growth.

  4. Cadmium distribution in rice plants grown in three different soils after application of pig manure with added cadmium.

    PubMed

    Han, Cunliang; Wu, Longhua; Tan, Weina; Zhong, Daoxu; Huang, Yujuan; Luo, Yongming; Christie, Peter

    2012-08-01

    A glasshouse pot experiment was conducted to investigate Cd concentrations in the aboveground parts of two consecutive crops of rice and Cd availability in three different soils (loam, silt loam, and sandy loam) after application of pig manure with added Cd. Soil pH tended to increase with increasing application rate of pig manure from 1 to 3% (w/w, oven dry basis). Soil diethylene triamine pentaacetic acid (DTPA) extractable Cd showed a clear positive correlation with soil total Cd content and increased with increasing Cd amendment of the manure but showed no difference between the two manure application rates. Cd concentrations in the grain, husk, and straw were significantly and positively correlated with soil DTPA-extractable Cd (p < 0.001). Within each level of manure Cd, the higher rate (3%) of manure produced lower Cd concentrations in the grain, husk, and straw on all three soils than did the lower rate (1%) after the first crop, but this no longer occurred after the growth of the second crop. Grain Cd concentrations exceeded the Chinese National Food Quality Standard (0.2 mg kg(-1)) most often on the loam, with intermediate frequency on the silt loam, and least often on the sandy loam, the soil with the highest pH and lowest organic carbon content and cation exchange capacity. PMID:22189706

  5. Ethanol Extract of Antrodia camphorata Grown on Germinated Brown Rice Suppresses Inflammatory Responses in Mice with Acute DSS-Induced Colitis

    PubMed Central

    Park, Dong Ki; Park, Hye-Jin

    2013-01-01

    The anti-inflammatory activity of Antrodia camphorata (AC) grown on germinated brown rice (CBR) extract was evaluated in vitro and in vivo. CBR suppressed the release of nitric oxide (NO) and prostaglandin (PG) E2 from lipopolysaccharide-(LPS-)stimulated RAW264.7 cells. CBR inhibited the level of inducible nitric oxide synthase (iNOS) and cyclooxygenase-(COX-)2 proteins, and it activated p38-MAPK, extracellular signal-related kinases (ERK), and NF-κB in LPS-stimulated RAW264.7 macrophages. LPS-induced tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA expression was reduced in CBR-treated RAW264.7 cells. In concert with in vitro data, CBR suppressed the levels of dextran-sulfate-sodium-(DSS-)induced iNOS and COX-2 proteins in the colon tissue. CBR treatment inhibited activated p38-MAPK, ERK, and NF-κB proteins in the colon tissue of DSS-induced mice. TNF-α and IL-6 mRNA expression was reduced in DSS+CBR-treated mice. The disease activity index and histological scores were significantly lower in CBR-treated mice (500 mg/kg/day) than in DSS-treated mice (P < 0.05 versus DSS). This is the first report of anti-inflammatory activity of CBR in DSS-induced acute colitis. These results suggest that CBR is a promising, potential agent for preventing acute colitis through the inhibition of NF-κB signaling and its upstream signaling molecules, including MAPKs. PMID:23818935

  6. Genome of Pseudomonas sp. FeS53a, a Putative Plant Growth-Promoting Bacterium Associated with Rice Grown in Iron-Stressed Soils.

    PubMed

    de Souza, Rocheli; Sant'Anna, Fernando Hayashi; Ambrosini, Adriana; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi; Passaglia, Luciane M P

    2015-01-01

    Pseudomonas sp. FeS53a was isolated from the roots of rice plants cultivated in one area with a well-established history of iron toxicity. The FeS53a genome sequence provides the genetic basis for understanding its lifestyle and survival in association with rice in conditions of iron toxicity. PMID:25838496

  7. Genome of Pseudomonas sp. FeS53a, a Putative Plant Growth-Promoting Bacterium Associated with Rice Grown in Iron-Stressed Soils

    PubMed Central

    de Souza, Rocheli; Sant’Anna, Fernando Hayashi; Ambrosini, Adriana; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi

    2015-01-01

    Pseudomonas sp. FeS53a was isolated from the roots of rice plants cultivated in one area with a well-established history of iron toxicity. The FeS53a genome sequence provides the genetic basis for understanding its lifestyle and survival in association with rice in conditions of iron toxicity. PMID:25838496

  8. SSR MARKER CONFIRMATION OF RECIPROCAL OUTCROSSING RATES BETWEEN RICE AND RED RICE LINES IN ARKANSAS OVER A FIVE-YEAR PERIOD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Outcrossing between rice and red rice can negatively impact the rice industry, especially when herbicide-resistant rice cultivars are grown. Previous research has indicated that outcrossing between rice and red rice in Arkansas farm fields can occur with either plant type serving as the pollen dono...

  9. Seed Priming Alters the Production and Detoxification of Reactive Oxygen Intermediates in Rice Seedlings Grown under Sub-optimal Temperature and Nutrient Supply

    PubMed Central

    Hussain, Saddam; Khan, Fahad; Cao, Weidong; Wu, Lishu; Geng, Mingjian

    2016-01-01

    The production and detoxification of reactive oxygen intermediates (ROIs) play an important role in the plant response to nutrient and environmental stresses. The present study demonstrated the behavior of growth, ROIs-production and their detoxification in primed and non-primed rice seedlings under chilling stress (18°C) and nitrogen-(N), phosphorus-(P), or potassium-(K) deprivation. The results revealed that chilling stress as well as deprivation of any mineral nutrient severely hampered the seedling growth of rice, however, seed priming treatments (particularly selenium- or salicylic acid-priming), were effective in enhancing the rice growth under stress conditions. The N-deprivation caused the maximum reduction in shoot growth, while the root growth was only decreased by P- or K-deprivation. Although, N-deprivation enhanced the root length of rice, the root fresh weight was unaffected. Rate of lipid peroxidation as well as the production of ROIs, was generally increased under stress conditions; the K-deprived seedlings recorded significantly lower production of ROIs than N- or P-deprived seedlings. The responses of enzymatic and non-enzymatic antioxidants in rice seedlings to chilling stress were variable with nutrient management regime. All the seed priming were found to trigger or at least maintain the antioxidant defense system of rice seedlings. Notably, the levels of ROIs were significantly reduced by seed priming treatments, which were concomitant with the activities of ROIs-producing enzymes (monoamine oxidase and xanthine oxidase), under all studied conditions. Based on these findings, we put forward the hypothesis that along with role of ROIs-scavenging enzymes, the greater tolerance of primed rice seedlings can also be due to the reduced activity of ROIs-producing enzymes. PMID:27092157

  10. Accumulation of (137)Cs by rice grown in four types of soil contaminated by the Fukushima Dai-ichi Nuclear Power Plant accident in 2011 and 2012.

    PubMed

    Fujimura, Shigeto; Muramatsu, Yasuyuki; Ohno, Takeshi; Saitou, Masaaki; Suzuki, Yasukazu; Kobayashi, Tomoyuki; Yoshioka, Kunio; Ueda, Yoshikatsu

    2015-02-01

    The ability to predict radiocesium transfer from soil to agricultural products is necessary for assessing management options in a radiocesium contaminated area. In this study, we evaluated the differences in transfer factors among soil samples and the differences in transfer factors between the first and the second years of contamination in rice. We employed pot experiments using four types of soils that are representative of the agricultural soils present in the Fukushima Prefecture contaminated by (137)Cs released from the Fukushima Dai-ichi Nuclear Power Plant after the March 2011 accident. The experiments were conducted during the 2011 and 2012 growing seasons. The geometric mean of transfer factors for brown rice and inedible rice part was 0.011 and 0.031, respectively, in 2011 and 0.0061 and 0.020, respectively, in 2012. The average decreasing rate of the transfer factor was 40% and 30% in brown rice and inedible rice part, respectively, from 2011 to 2012, presumably owing to the irreversible sorption of (137)Cs to clay minerals. PMID:25461516

  11. GENE FLOW BETWEEN RED RICE AND RICE IN HERBICIDE RESISTANT RICE FIELDS: EVALUATING RISKS AND MANAGEMENT OPTIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Imidazolinone (IMI)-resistant rice cultivars have been increasingly adopted in the southern U.S. since their initial introduction in 2002, largely due to the newly acquired control of red rice that is now possible in these systems. It is estimated that IMI rice is being grown on 20 to 25% of the ac...

  12. Genome Wide Association Mapping of Grain Arsenic, Copper, Molybdenum and Zinc in Rice (Oryza sativa L.) Grown at Four International Field Sites

    PubMed Central

    Norton, Gareth J.; Douglas, Alex; Lahner, Brett; Yakubova, Elena; Guerinot, Mary Lou; Pinson, Shannon R. M.; Tarpley, Lee; Eizenga, Georgia C.; McGrath, Steve P.; Zhao, Fang-Jie; Islam, M. Rafiqul; Islam, Shofiqul; Duan, Guilan; Zhu, Yongguan; Salt, David E.; Meharg, Andrew A.; Price, Adam H.

    2014-01-01

    The mineral concentrations in cereals are important for human health, especially for individuals who consume a cereal subsistence diet. A number of elements, such as zinc, are required within the diet, while some elements are toxic to humans, for example arsenic. In this study we carry out genome-wide association (GWA) mapping of grain concentrations of arsenic, copper, molybdenum and zinc in brown rice using an established rice diversity panel of ∼300 accessions and 36.9 k single nucleotide polymorphisms (SNPs). The study was performed across five environments: one field site in Bangladesh, one in China and two in the US, with one of the US sites repeated over two years. GWA mapping on the whole dataset and on separate subpopulations of rice revealed a large number of loci significantly associated with variation in grain arsenic, copper, molybdenum and zinc. Seventeen of these loci were detected in data obtained from grain cultivated in more than one field location, and six co-localise with previously identified quantitative trait loci. Additionally, a number of candidate genes for the uptake or transport of these elements were located near significantly associated SNPs (within 200 kb, the estimated global linkage disequilibrium previously employed in this rice panel). This analysis highlights a number of genomic regions and candidate genes for further analysis as well as the challenges faced when mapping environmentally-variable traits in a highly genetically structured diversity panel. PMID:24586963

  13. Nitrogen fertilization on center pivot sprinkler irrigated rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three rice (Oryza sativa) experiments were conducted to determine the effects of nitrogen (N) form and timing of application on growth and yield of sprinkler irrigated rice compared to flood irrigated rice. Three rice cultivars (two conventional, one hybrid) were grown under a center pivot irrigatio...

  14. Non-Destructive Monitoring of Rice by Hyperspectral In-Field Spectrometry and Uav-Based Remote Sensing: Case Study of Field-Grown Rice in North Rhine-Westphalia Germany

    NASA Astrophysics Data System (ADS)

    Willkomm, M.; Bolten, A.; Bareth, G.

    2016-06-01

    In the context of an increasing world population, the demand for agricultural crops is continuously rising. Especially rice plays a key role in food security, not only in Asia. To increase crop production of rice, either productivity of plants has to be improved or new cultivation areas have to be found. In this context, our study investigated crop growth of paddy rice (Oryza Sativa J.) in Germany. An experimental field in the vegetation period of 2014 with two nitrogen treatments was conducted using remote sensing methods. The research project focussed on two main aspects: (1) the potential of UAV-based and hyperspectral remote sensing methods to monitor selected growth parameters at different phenological stages; (2) the potential of paddy rice cultivation under the present climate condition in western Germany. We applied a low-cost UAV-system (Unmanned Aerial Vehicle) to generate high resolution Crop Surface Models (CSM). These were compared with hyperspectral in-field measurements and directly measured agronomic parameters (fresh and dry aboveground biomass (AGB), leaf-area-index (LAI) and plant nitrogen concentration (PNC)). For all acquisition dates we could determine single in-field structures in the CSM (e.g. distribution of hills) and different growth characteristics between the nitrogen treatments. Especially in the second half of the growing season, the plants with higher nitrogen availability were about 25 - 30 % larger. The plant height in the CSM correlates particularly with fresh AGB and the LAI (R2 > 0.8). Thus, the conducted methods for plant growth monitoring can be a contribution for precision agriculture approaches.

  15. Influence of plant species and environmental conditions on epiphytic and endophytic pink-pigmented facultative methylotrophic bacterial populations associated with field-grown rice cultivars.

    PubMed

    Madhaiyan, Munusamy; Poonguzhali, Selvaraj; Sa, Tongmin

    2007-10-01

    The total methylotrophic population associated with rice plants from different cultivars was enumerated at three different stages: vegetative, flowering, and harvesting. The bacterial population in the leaf, rhizosphere soil, endophytic in the stem and roots, and epiphytic in the florets and grains were determined from four rice cultivars, Il-mi, Nam-pyeoung, O-dae, and Dong-jin, sampled from three different field sites. The methylotrophic bacteria isolated on AMS media containing 0.5% methanol as the sole carbon source uniformly showed three distinct morphologies, which were recorded as separate groups and their distribution among the various samples was determined using the ecophysiological index. The growth stage at the time of sampling had a more significant effect on the methylotrophic population and their distribution than the field site or cultivar. A similar effect was also observed for the PPFMs, where their population in different plant parts increased from V10 to R4 and then decreased towards stage R9. A canonical discriminant analysis of the PPFM population from different parts of rice showed clear variations among the cultivars, sampled sites, and growth stages, although the variations were more prominent among the growth stages. PMID:18156780

  16. Characterizing irrigation water requirements for rice production from the Arkansas Rice Research Verification Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated rice irrigation water use in the University of Arkansas Rice Research Verification Program between the years of 2003 and 2011. Irrigation water use averaged 747 mm (29.4 inches) over the nine years. A significant 40% water savings was reported for rice grown under a zero gr...

  17. Restricting the above ground sink corrects the root/shoot ratio and substantially boosts the yield potential per panicle in field-grown rice (Oryza sativa L.).

    PubMed

    Nada, Reham M; Abogadallah, Gaber M

    2016-04-01

    Rice has shallow, weak roots, but it is unknown how much increase in yield potential could be achieved if the root/shoot ratio is corrected. Removing all tillers except the main one, in a japonica (Sakha 101) and an indica (IR64) rice cultivar, instantly increased the root/shoot ratio from 0.21 to 1.16 in Sakha 101 and from 0.16 to 1.46 in IR64. Over 30 days after detillering, the root/shoot ratios of the detillered plants decreased to 0.49 in Sakha 101 and 0.46 in IR64 but remained significantly higher than in the controls. The detillered plants showed two- or fourfold increase in the main tiller fresh weight, as a consequence of more positive midday leaf relative water content (RWC), and consistently higher rates of stomatal conductance and photosynthesis, but not transpiration, compared with the controls. The enhanced photosynthesis in Sakha 101 after detillering resulted from both improved water status and higher Rubisco contents whereas in IR64, increasing the Rubisco content did not contribute to improving photosynthesis. Detillering did not increase the carbohydrate contents of leaves but prevented starch depletion at the end of grain filling. The leaf protein content during vegetative and reproductive stages, the grain filling rate, the number of filled grains per panicle were greatly improved, bringing about 38.3 and 35.9% increase in the harvested grain dry weight per panicle in Sakha 101 and IR64, respectively. We provide evidence that improving the root performance by increasing the root/shoot ratio would eliminate the current limitations to photosynthesis and growth in rice. PMID:26296302

  18. Pest and disease tolerance in rice cv Pusa Basmati as related to different locally available organic manures grown in new alluvail region of West Bengal, India.

    PubMed

    Rakshit, Amitava

    2013-06-15

    Field experiments were carried out to evaluate relative efficacy of organic manures in improving productivity, pest tolerance of rice in lateritic soil. Three commercial manures viz., Processed Municipality Waste (PMW), Vermicompost (VC) and Oil Cake Pellets (OCP) were assessed in relation to Farmyard Manure (FYM) and with Chemical Fertilizer (CF). Among the organic manures tested, FYM produced maximum grain yield. Maximum tolerance to pests and pathogens in terms of per cent affected hills/panicles was observed when manured with VC followed by FYM. Chemical fertilizer showed significantly higher per cent affected hills and plants compared to all other organic manures. Among the commercial manures, PMW emerged as a potential alternative to FYM and VC. PMID:24494531

  19. Blackbirds and the southern rice crop

    USGS Publications Warehouse

    Meanley, Brooke

    1971-01-01

    In the 1700's and 1800's, rice was grown in the lowlands of South Carolina, Georgia, and North Carolina - on the major migratory route of the bobolink (Dolichonyx oryzivorus), the historic "ricebird" of that area because of its consumption of ripening rice. By the late 1800's the rice-growing industry had largely shifted to the coastal prairies of Louisiana and Texas, which are bordered by some 5 million acres of marshland-breeding habitat for the redwinged blackbird (Agelaius phoeniceus) and the boat-tailed grackle (Cassidix mexicanus). By 1900, rice was being grown on the Grand Prairie of eastern Arkansas, which bestrides the largest blackbird flyway in the country. In recent decades, rice culture has spread to other sections of Arkansas and thence to contiguous areas in Louisiana, Mississippi, Tennesee, and Missouri. In effect, then, man has taken the rice to the blackbirds.

  20. Identification of rice blast resistance genes using international monogenic differentials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease, caused by the fungal pathogen Magnaporthe oryzae, is one of the most devastating diseases of rice that severely affects crop production in Jilin Province, Northeast China, where temperate japonica rice is primarily grown. In the present study, 44 representative local blast isolat...

  1. Diagnostics of the red rice problem in the U.S.A

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice was first grown in the United States in what is now North Carolina and South Carolina at the end of the 17th century. At the beginning of the 20th century, rice was being grown in North and South Carolina, Georgia, Louisiana (LA), and Arkansas (AR). Different red rice biotypes, including “str...

  2. Greenhouse gas emissions, irrigation water use, and arsenic concentrations; a common thread in rice water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice has historically been grown as a flooded crop in the United States. As competition for water resources has grown, there is interest in reducing water use in rice production so as to maintain a viable and sustainable rice industry into the future. An irrigation study was established in 2011 at ...

  3. Four new rice varieties for specialty markets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although conventional long grain rice varieties are grown on over 75% of the acreage in the US, there is interest in developing rice cultivars which possess specific qualities required for certain value-added markets. USDA ARS researchers at Beaumont, TX and Stuttgart, AR, in various collaborations ...

  4. Tropical Legume Crop Rotation and Nitrogen Fertilizer Effects on Agronomic and Nitrogen Efficiency of Rice

    PubMed Central

    Rahman, Motior M.; Islam, Aminul M.; Azirun, Sofian M.; Boyce, Amru N.

    2014-01-01

    Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 g N m−2 preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 g N m−2. No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE), nitrogen recovery efficiency (NRE), N uptake, and rice yield when legume crops were grown in rotation with rice. Rice after winged bean grown with N at the rate of 4 g N m−2 achieved significantly higher NRE, NAE, and N uptake in both years. Rice after winged bean grown without N fertilizer produced 13–23% higher grain yield than rice after fallow rotation with 8 g N m−2. The results revealed that rice after winged bean without fertilizer and rice after long bean with N fertilizer at the rate of 4 g N m−2 can produce rice yield equivalent to that of rice after fallow with N fertilizer at rates of 8 g N m−2. The NAE, NRE, and harvest index values for rice after winged bean or other legume crop rotation indicated a positive response for rice production without deteriorating soil fertility. PMID:24971378

  5. Rice Nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter presents the symptoms of deficiency and toxicity of the major and minor mineral nutrients in rice, as well as a current synopsis of nutrient transporters and their regulation. The availability of sequences from the recently completed rice genome has furthered the knowledge of how plants...

  6. Preferential association of endophytic bradyrhizobia with different rice cultivars and its implications for rice endophyte evolution.

    PubMed

    Piromyou, Pongdet; Greetatorn, Teerana; Teamtisong, Kamonluck; Okubo, Takashi; Shinoda, Ryo; Nuntakij, Achara; Tittabutr, Panlada; Boonkerd, Nantakorn; Minamisawa, Kiwamu; Teaumroong, Neung

    2015-05-01

    Plant colonization by bradyrhizobia is found not only in leguminous plants but also in nonleguminous species such as rice. To understand the evolution of the endophytic symbiosis of bradyrhizobia, the effect of the ecosystems of rice plantations on their associations was investigated. Samples were collected from various rice (Oryza sativa) tissues and crop rotational systems. The rice endophytic bradyrhizobia were isolated on the basis of oligotrophic properties, selective medium, and nodulation on siratro (Macroptilium atropurpureum). Six bradyrhizobial strains were obtained exclusively from rice grown in a crop rotational system. The isolates were separated into photosynthetic bradyrhizobia (PB) and nonphotosynthetic bradyrhizobia (non-PB). Thai bradyrhizobial strains promoted rice growth of Thai rice cultivars better than the Japanese bradyrhizobial strains. This implies that the rice cultivars possess characteristics that govern rice-bacterium associations. To examine whether leguminous plants in a rice plantation system support the persistence of rice endophytic bradyrhizobia, isolates were tested for legume nodulation. All PB strains formed symbioses with Aeschynomene indica and Aeschynomene evenia. On the other hand, non-PB strains were able to nodulate Aeschynomene americana, Vigna radiata, and M. atropurpureum but unable to nodulate either A. indica or A. evenia. Interestingly, the nodABC genes of all of these bradyrhizobial strains seem to exhibit low levels of similarity to those of Bradyrhizobium diazoefficiens USDA110 and Bradyrhizobium sp. strain ORS285. From these results, we discuss the evolution of the plant-bradyrhizobium association, including nonlegumes, in terms of photosynthetic lifestyle and nod-independent interactions. PMID:25710371

  7. Preferential Association of Endophytic Bradyrhizobia with Different Rice Cultivars and Its Implications for Rice Endophyte Evolution

    PubMed Central

    Piromyou, Pongdet; Greetatorn, Teerana; Teamtisong, Kamonluck; Okubo, Takashi; Shinoda, Ryo; Nuntakij, Achara; Tittabutr, Panlada; Boonkerd, Nantakorn

    2015-01-01

    Plant colonization by bradyrhizobia is found not only in leguminous plants but also in nonleguminous species such as rice. To understand the evolution of the endophytic symbiosis of bradyrhizobia, the effect of the ecosystems of rice plantations on their associations was investigated. Samples were collected from various rice (Oryza sativa) tissues and crop rotational systems. The rice endophytic bradyrhizobia were isolated on the basis of oligotrophic properties, selective medium, and nodulation on siratro (Macroptilium atropurpureum). Six bradyrhizobial strains were obtained exclusively from rice grown in a crop rotational system. The isolates were separated into photosynthetic bradyrhizobia (PB) and nonphotosynthetic bradyrhizobia (non-PB). Thai bradyrhizobial strains promoted rice growth of Thai rice cultivars better than the Japanese bradyrhizobial strains. This implies that the rice cultivars possess characteristics that govern rice-bacterium associations. To examine whether leguminous plants in a rice plantation system support the persistence of rice endophytic bradyrhizobia, isolates were tested for legume nodulation. All PB strains formed symbioses with Aeschynomene indica and Aeschynomene evenia. On the other hand, non-PB strains were able to nodulate Aeschynomene americana, Vigna radiata, and M. atropurpureum but unable to nodulate either A. indica or A. evenia. Interestingly, the nodABC genes of all of these bradyrhizobial strains seem to exhibit low levels of similarity to those of Bradyrhizobium diazoefficiens USDA110 and Bradyrhizobium sp. strain ORS285. From these results, we discuss the evolution of the plant-bradyrhizobium association, including nonlegumes, in terms of photosynthetic lifestyle and nod-independent interactions. PMID:25710371

  8. Reducing water use for rice production with remote monitoring and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is an important food crop worldwide and farmers in the Lower Mississippi Water Resource Area of the U.S. grew 68% of the total U.S. crop. U.S.-produced rice is grown almost exclusively in a flooded culture and the water applied to rice has resulted in high energy costs and water shortages in so...

  9. Effects of Organic Fertility Management on Physicochemical Properties and Sensory Quality of Diverse Rice Cultivars.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The demand for organically-grown rice has increased with consumer demand for organic foods. The objective of this research was to determine if there are physicochemical differences in organically- and conventionally-grown rice that contribute to flavor and texture differences, as determined by desc...

  10. An overview of global rice production, supply, trade, and consumption.

    PubMed

    Muthayya, Sumithra; Sugimoto, Jonathan D; Montgomery, Scott; Maberly, Glen F

    2014-09-01

    Rice is the staple food for over half the world's population. Approximately 480 million metric tons of milled rice is produced annually. China and India alone account for ∼50% of the rice grown and consumed. Rice provides up to 50% of the dietary caloric supply for millions living in poverty in Asia and is, therefore, critical for food security. It is becoming an important food staple in both Latin America and Africa. Record increases in rice production have been observed since the start of the Green Revolution. However, rice remains one of the most protected food commodities in world trade. Rice is a poor source of vitamins and minerals, and losses occur during the milling process. Populations that subsist on rice are at high risk of vitamin and mineral deficiency. Improved technologies to fortify rice have the potential to address these deficiencies and their associated adverse health effects. With the rice industry consolidating in many countries, there are opportunities to fortify a significant share of rice for distribution or for use in government safety net programs that target those most in need, especially women and children. Multisectoral approaches are needed for the promotion and implementation of rice fortification in countries. PMID:25224455

  11. Oryza nivara, a wild relative of cultivated rice, is a source of genes for improving seedling vigor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice (Oryza sativa L.) wild relatives are a potential source of genetic diversity for cultivated rice improvement. An advanced backcross population was derived from the U.S. temperate japonica rice variety, M-202, a medium grain commercial cultivar grown in California, crossed with O. nivara Sharma...

  12. Crop management strategies and disease resistance control the severity of false smut and kernel smut of rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    False smut and kernel smut are common diseases of rice capable of severe epidemics with dramatic yield losses. The importance of rice smuts is often overlooked in the US, and highly susceptible varieties are now being grown on the majority of production acres in the southern rice producing states. O...

  13. The impact of herbicide-resistant rice technology on phenotypic diversity and population structure of United States weedy rice.

    PubMed

    Burgos, Nilda Roma; Singh, Vijay; Tseng, Te Ming; Black, Howard; Young, Nelson D; Huang, Zhongyun; Hyma, Katie E; Gealy, David R; Caicedo, Ana L

    2014-11-01

    The use of herbicide-resistant (HR) Clearfield rice (Oryza sativa) to control weedy rice has increased in the past 12 years to constitute about 60% of rice acreage in Arkansas, where most U.S. rice is grown. To assess the impact of HR cultivated rice on the herbicide resistance and population structure of weedy rice, weedy samples were collected from commercial fields with a history of Clearfield rice. Panicles from each weedy type were harvested and tested for resistance to imazethapyr. The majority of plants sampled had at least 20% resistant offspring. These resistant weeds were 97 to 199 cm tall and initiated flowering from 78 to 128 d, generally later than recorded for accessions collected prior to the widespread use of Clearfield rice (i.e. historical accessions). Whereas the majority (70%) of historical accessions had straw-colored hulls, only 30% of contemporary HR weedy rice had straw-colored hulls. Analysis of genotyping-by-sequencing data showed that HR weeds were not genetically structured according to hull color, whereas historical weedy rice was separated into straw-hull and black-hull populations. A significant portion of the local rice crop genome was introgressed into HR weedy rice, which was rare in historical weedy accessions. Admixture analyses showed that HR weeds tend to possess crop haplotypes in the portion of chromosome 2 containing the ACETOLACTATE SYNTHASE gene, which confers herbicide resistance to Clearfield rice. Thus, U.S. HR weedy rice is a distinct population relative to historical weedy rice and shows modifications in morphology and phenology that are relevant to weed management. PMID:25122473

  14. Effects of Fertilizer Inputs and Conventional Versus Organic Management on the Physiocochemical Properties and Sensory Quality of Diverse Rice Cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The demand for organically-grown rice has increased with consumer demand for organic foods. The objective of this research was to determine if there are physicochemical differences in organically- and conventionally-grown rice that contribute to flavor and texture differences, as determined by desc...

  15. Abandoned Rice Fields Make Streams Go Dry in Upland Landscapes

    NASA Astrophysics Data System (ADS)

    Jayawickreme, D.

    2015-12-01

    In South Asia, new economic realities are driving many rural rice farmers out of agriculture. With increasing neglect, abandonment, and rising conversions of centuries old rice fields into other uses, ecological and environmental consequences of these transitions are becoming progressively clear. Field observations in Sri Lanka's central highlands suggest that small shifts in rice to non-rice land uses in headwater watersheds can have a domino effect on the productivity and viability of rice fields and other ecological systems downstream by inflicting groundwater recharge reductions, lowering groundwater yields, and causing other hydrological changes. Preliminary analysis shows that although rice itself is a very water intensive crop, the presence of rain-fed upland rice-fields is hugely beneficial to the watersheds they reside. In particular, water benefits of rice appear to be derived from ponded conditions (3-5 inches of standing water) in which rice is grown, and the contribution rice fields makes to enhance water retention and storage capacity of their watersheds during the monsoon season that coincide with the cropping season. In the absence of well managed rice-fields, hilly upland landscapes produce more runoff and retain little rainwater during the wet season. Furthermore, after centuries of intensive use, much of South Asia's rice fields are nutrient poor and minimally productive without fertilizer applications and other interventions. Consequently, when abandoned, soil erosion and other impacts that affect aquatic ecosystems and watershed health also emerge. Despite these multiple concerns however, little research is currently done to better understand the environmental significance of rice cultivations that are a dominant land-use in many South Asian landscapes. The aim of this presentation is to stir interest among the scientific community to engage more broadly in rice, water, and environmental change research in the face of new economic realities in

  16. Differentiation of rice cultivar for grain arsenic content associated with soil and water management in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reduction of arsenic (As) in rice grains play an important role in improvement of food quality and minimization of any potential risk from dietary exposure. Twenty-one worldwide cultivars including both indica and japonica subspecies were grown under two water treatments, saturated soil and consiste...

  17. How does contamination of rice soils with Cd and Zn cause high incidence of human Cd disease in subsistence rice farmers?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice (Oryza sativa L.) grown on Zn mine waste contaminated soils has caused unequivocal Cd effects on kidney and occasional bone disease (itai-itai) in subsistence rice farmers, but high intake of Cd from other foods has not caused similar effects. Research has clarified two important topics about ...

  18. Contact urticaria from rice.

    PubMed

    Yamakawa, Y; Ohsuna, H; Aihara, M; Tsubaki, K; Ikezawa, Z

    2001-02-01

    A 30-year-old man with atopic dermatitis had had erythema and itching of the hands after washing rice in water, though he had always eaten cooked rice without problems. Handling test with water used to wash regular rice was performed on abraded hands, and produced urticarial erythema after several minutes. Applications of water used to wash allergen-reduced rice were negative for urticarial reaction. Prick test with water used to wash regular rice was +++. However prick test reaction with water used to wash allergen-reduced rice was +. Histamine-release test of regular rice-washing water was grade 3 and that of allergen-reduced rice grade 1. In immunoblotting analysis with regular rice washing water, there were no bands with this patient. These results suggest that the allergen responsible for contact urticaria in this patient might be water-soluble, heat-unstable, and not contained in allergen-reduced rice. PMID:11205411

  19. Rice ( Oryza) hemoglobins

    PubMed Central

    Arredondo-Peter, Raúl; Moran, Jose F.; Sarath, Gautam

    2014-01-01

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice ( Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a single copy of the thb gene exist in Oryza sativa var. indica and O. sativa var. japonica, Hb transcripts coexist in rice organs and Hb polypeptides exist in rice embryonic and vegetative organs and in the cytoplasm of differentiating cells. At the structural level, the crystal structure of rice Hb1 has been elucidated, and the structures of the other rice Hbs have been modeled. Kinetic analysis indicated that rice Hb1 and 2, and possibly rice Hb3 and 4, exhibit a very high affinity for O 2, whereas rice Hb5 and tHb possibly exhibit a low to moderate affinity for O 2. Based on the accumulated information on the properties of rice Hbs and data from the analysis of other plant and non-plant Hbs, it is likely that Hbs play a variety of roles in rice organs, including O 2-transport, O 2-sensing, NO-scavenging and redox-signaling. From an evolutionary perspective, an outline for the evolution of rice Hbs is available. Rice nshb and thb genes vertically evolved through different lineages, rice nsHbs evolved into clade I and clade II lineages and rice nshbs and thbs evolved under the effect of neutral selection. This review also reveals lacunae in our ability to completely understand rice Hbs. Primary lacunae are the absence of experimental information about the precise functions of rice Hbs, the properties of modeled rice Hbs and the cis-elements and trans-acting factors that regulate the expression of rice hb genes, and the partial understanding of the evolution of rice Hbs. PMID:25653837

  20. Aflatoxins in Rice Artificially Contaminated with Aflatoxin-producing Aspergillus flavus under Natural Storage in Japan.

    PubMed

    Sugihara, Satoshi; Doi, Hiroyuki; Kato, Masahiko; Mitoh, Yoshihiro; Tsuda, Toshihide; Ikeda, Satoru

    2016-06-01

    Aflatoxin (AFT) contamination is frequent in foods grown in tropical regions, including rice. Although AFTs are generally not found in temperate-region foods, global warming has affected typical temperate-region climates, potentially permitting the contamination of foods with AFT-producing Aspergillus flavus (A. flavus). Here we investigated the AFT production in rice during storage under natural climate conditions in Japan. We examined AFTs in brown rice and rough rice artificially contaminated with A. flavus for 1 year in Japan, and we subjected AFTs in white rice to the same treatment in airtight containers and examined the samples in warm and cold seasons, simulating the storage of white rice in general households. In the brown rice, AFTs increased after 2 months (March) and peaked after 9 months (October). The AFT contamination in the rough rice was minimal. After the polishing and cooking of the brown rice, AFTs were undetectable. In the white rice stored in airtight containers, AFTs increased after 1 month (August) and peaked after 2 months (September). Minimal AFTs were detected in the cold season. Thus, AFT contamination in rice may occur in temperate regions following A. flavus contamination. The storage of rice as rough rice could provide be useful for avoiding AFT contamination. PMID:27339205

  1. Mitigation of arsenic accumulation in rice with water management and silicon fertilization.

    PubMed

    Li, R Y; Stroud, J L; Ma, J F; McGrath, S P; Zhao, F J

    2009-05-15

    Rice represents a major route of As exposure in populations that depend on a rice diet. Practical measures are needed to mitigate the problem of excessive As accumulation in paddy rice. Two potential mitigation methods, management of the water regime and Si fertilization, were investigated under greenhouse conditions. Growing rice aerobically during the entire rice growth duration resulted in the leastAs accumulation. Maintaining aerobic conditions during either vegetative or reproductive stage of rice growth also decreased As accumulation in rice straw and grain significantly compared with rice grown under flooded conditions. The effect of water management regimes was consistent with the observed effect of flooding-induced arsenite mobilization in the soil solution. Aerobic treatments increased the percentage of inorganic As in grain, but the concentrations of inorganic As remained lower than in the flooded rice. Silicon fertilization decreased the total As concentration in straw and grain by 78 and 16%, respectively, even though Si addition increased As concentration in the soil solution. Silicon also significantly influenced As speciation in rice grain and husk by enhancing methylation. Silicon decreased the inorganic As concentration in grain by 59% while increasing the concentration of dimethylarsinic acid (DMA) by 33%. There were also significant differences between two rice genotypes in grain As speciation. This study demonstrated that water management Si fertilization, and selection of rice cultivars are effective measures that can be used to reduce As accumulation in rice. PMID:19544887

  2. Genetic and field management strategies to enhance the nutritional value of rice grains and limit accumulation of undesirable elements such as arsenic

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enhancing the nutritional value of rice grains is of particular interest because rice is a primary dietary component for more than half of the world’s population, and is a primary source of nutrients in many underdeveloped countries. Because rice can be grown under both flooded and unflooded field ...

  3. Spatially resolved elemental mapping of two U.S. rice core collection grain accessions with diverse arsenic accumulation characteristics via synchrotron x-Ray fluorescence microscopy (SXRF)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The discovery of arsenic in higher than expected concentrations in rice grown in the South Central United States and worldwide has prompted further study to ensure the safety of rice, and rice based products such as infant cereals. In the U.S. arsenic is thought to originate from former arsenical pe...

  4. A digital photography and analysis system for estimation of root and shoot development in rice weed suppression studies in the field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice germplasm with an inherent ability to suppress weeds can potentially improve the economics and sustainability of weed control in rice. We devised a simple, rapid, and inexpensive digital imaging system to quantify several shoot and root growth characteristics in field-grown rice plants that ha...

  5. Arsenic biotransformation by Streptomyces sp. isolated from rice rhizosphere.

    PubMed

    Kuramata, Masato; Sakakibara, Futa; Kataoka, Ryota; Abe, Tadashi; Asano, Maki; Baba, Koji; Takagi, Kazuhiro; Ishikawa, Satoru

    2015-06-01

    Isolation and functional analysis of microbes mediating the methylation of arsenic (As) in paddy soils is important for understanding the origin of dimethylarsinic acid (DMA) in rice grains. Here, we isolated from the rice rhizosphere a unique bacterium responsible for As methylation. Strain GSRB54, which was isolated from the roots of rice plants grown in As-contaminated paddy soil under anaerobic conditions, was classified into the genus Streptomyces by 16S ribosomal RNA sequencing. Sequence analysis of the arsenite S-adenosylmethionine methyltransferase (arsM) gene revealed that GSRB54 arsM was phylogenetically different from known arsM genes in other bacteria. This strain produced DMA and monomethylarsonic acid when cultured in liquid medium containing arsenite [As(III)]. Heterologous expression of GSRB54 arsM in Escherichia coli promoted methylation of As(III) by converting it into DMA and trimethylarsine oxide. These results demonstrate that strain GSRB54 has a strong ability to methylate As. In addition, DMA was detected in the shoots of rice grown in liquid medium inoculated with GSRB54 and containing As(III). Since Streptomyces are generally aerobic bacteria, we speculate that strain GSRB54 inhabits the oxidative zone around roots of paddy rice and is associated with DMA accumulation in rice grains through As methylation in the rice rhizosphere. PMID:25039305

  6. Association of arsenic concentration and speciation with straighthead disease in US produced rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent reports have indicated that rice when grown under anaerobic flooded field conditions can accumulate high levels of grain arsenic (As). This is a public health concern due to the high daily consumption of rice by some populations. The As-based herbicide (monosodium methanearsonate, MSMA) has ...

  7. Utilizing wild species to improve cultivated rice for yield, pest resistance, and response to climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 158 million hectares of rice are grown in the world providing a staple food for more than half the world’s population. Although there are several species of Oryza, essentially all cultivated rice is derived from O. sativa which can be genomically differentiated into five sub-populations. There ...

  8. Distribution of aflatoxins in shelling and milling fractions of naturally contaminated rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to determine the distribution of an economically-important class of mycotoxins, the aflatoxins, in rice milling fractions. Rice plants grown under field production condition are frequently infected with types of pathogenic fungi which produce toxic metabolites (mycot...

  9. Effect of Rice Cultivation Systems on Indigenous Arbuscular Mycorrhizal Fungal Community Structure

    PubMed Central

    Watanarojanaporn, Nantida; Boonkerd, Nantakorn; Tittabutr, Panlada; Longtonglang, Aphakorn; Young, J. Peter W.; Teaumroong, Neung

    2013-01-01

    Arbuscular mycorrhizal fungi (AMF) in an agricultural ecosystem are necessary for proper management of beneficial symbiosis. Here we explored how the patterns of the AMF community in rice roots were affected by rice cultivation systems (the system of rice intensification [SRI] and the conventional rice cultivation system [CS]), and by compost application during growth stages. Rice plants harvested from SRI-managed plots exhibited considerably higher total biomass, root dry weight, and seed fill than those obtained from conventionally managed plots. Our findings revealed that all AMF sequences observed from CS plots belonged (only) to the genus Glomus, colonizing in rice roots grown under this type of cultivation, while rice roots sown in SRI showed sequences belonging to both Glomus and Acaulospora. The AMF community was compared between the different cultivation types (CS and SRI) and compost applications by principle component analysis. In all rice growth stages, AMF assemblages of CS management were not separated from those of SRI management. The distribution of AMF community composition based on T-RFLP data showed that the AMF community structure was different among four cultivation systems, and there was a gradual increase of Shannon-Weaver indices of diversity (H′) of the AMF community under SRI during growth stages. The results of this research indicated that rice grown in SRI-managed plots had more diverse AMF communities than those grown in CS plots. PMID:23719585

  10. Effect of rice cultivation systems on indigenous arbuscular mycorrhizal fungal community structure.

    PubMed

    Watanarojanaporn, Nantida; Boonkerd, Nantakorn; Tittabutr, Panlada; Longtonglang, Aphakorn; Young, J Peter W; Teaumroong, Neung

    2013-01-01

    Arbuscular mycorrhizal fungi (AMF) in an agricultural ecosystem are necessary for proper management of beneficial symbiosis. Here we explored how the patterns of the AMF community in rice roots were affected by rice cultivation systems (the system of rice intensification [SRI] and the conventional rice cultivation system [CS]), and by compost application during growth stages. Rice plants harvested from SRI-managed plots exhibited considerably higher total biomass, root dry weight, and seed fill than those obtained from conventionally managed plots. Our findings revealed that all AMF sequences observed from CS plots belonged (only) to the genus Glomus, colonizing in rice roots grown under this type of cultivation, while rice roots sown in SRI showed sequences belonging to both Glomus and Acaulospora. The AMF community was compared between the different cultivation types (CS and SRI) and compost applications by principle component analysis. In all rice growth stages, AMF assemblages of CS management were not separated from those of SRI management. The distribution of AMF community composition based on T-RFLP data showed that the AMF community structure was different among four cultivation systems, and there was a gradual increase of Shannon-Weaver indices of diversity (H') of the AMF community under SRI during growth stages. The results of this research indicated that rice grown in SRI-managed plots had more diverse AMF communities than those grown in CS plots. PMID:23719585

  11. Localization and speciation of arsenic and trace elements in rice tissues

    SciTech Connect

    Smith, Euan; Kempson, Ivan; Juhasz, Albert L.; Weber, John; Skinner, William M.; Gräfe, Markus

    2009-09-14

    The consumption of arsenic (As) contaminated rice is an important exposure route for humans in countries where rice cultivation employs As contaminated irrigation water. Arsenic toxicity and mobility are a function of its chemical-speciation. The distribution and identification of As in the rice plant are hence necessary to determine the uptake, transformation and potential risk posed by As contaminated rice. In this study we report on the distribution and chemical-speciation of As in rice (Oryza sativa Quest) by X-ray fluorescence (XRF) and X-ray absorption near edge structure (XANES) measurements of rice plants grown in As contaminated paddy water. Investigations of {mu}XRF images from rice tissues found that As was present in all rice tissues, and its presence correlated with the presence of iron at the root surface and copper in the rice leaf. X-ray absorption near edge structure analysis of rice tissues identified that inorganic As was the predominant form of As in all rice tissues studied, and that arsenite became increasingly dominant in the aerial portion of the rice plant.

  12. The Impact of Herbicide-Resistant Rice Technology on Phenotypic Diversity and Population Structure of United States Weedy Rice1[W][OPEN

    PubMed Central

    Burgos, Nilda Roma; Singh, Vijay; Tseng, Te Ming; Black, Howard; Young, Nelson D.; Huang, Zhongyun; Hyma, Katie E.; Gealy, David R.; Caicedo, Ana L.

    2014-01-01

    The use of herbicide-resistant (HR) Clearfield rice (Oryza sativa) to control weedy rice has increased in the past 12 years to constitute about 60% of rice acreage in Arkansas, where most U.S. rice is grown. To assess the impact of HR cultivated rice on the herbicide resistance and population structure of weedy rice, weedy samples were collected from commercial fields with a history of Clearfield rice. Panicles from each weedy type were harvested and tested for resistance to imazethapyr. The majority of plants sampled had at least 20% resistant offspring. These resistant weeds were 97 to 199 cm tall and initiated flowering from 78 to 128 d, generally later than recorded for accessions collected prior to the widespread use of Clearfield rice (i.e. historical accessions). Whereas the majority (70%) of historical accessions had straw-colored hulls, only 30% of contemporary HR weedy rice had straw-colored hulls. Analysis of genotyping-by-sequencing data showed that HR weeds were not genetically structured according to hull color, whereas historical weedy rice was separated into straw-hull and black-hull populations. A significant portion of the local rice crop genome was introgressed into HR weedy rice, which was rare in historical weedy accessions. Admixture analyses showed that HR weeds tend to possess crop haplotypes in the portion of chromosome 2 containing the ACETOLACTATE SYNTHASE gene, which confers herbicide resistance to Clearfield rice. Thus, U.S. HR weedy rice is a distinct population relative to historical weedy rice and shows modifications in morphology and phenology that are relevant to weed management. PMID:25122473

  13. Linkage Mapping of Stem Saccharification Digestibility in Rice

    PubMed Central

    Hua, Cangmei; Sun, Lili; Ali, Imran; Huang, Linli; Yu, Chunyan; Simister, Rachael; Steele-King, Clare; Gan, Yinbo; McQueen-Mason, Simon J.

    2016-01-01

    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. PMID:27415441

  14. Linkage Mapping of Stem Saccharification Digestibility in Rice.

    PubMed

    Liu, Bohan; Gómez, Leonardo D; Hua, Cangmei; Sun, Lili; Ali, Imran; Huang, Linli; Yu, Chunyan; Simister, Rachael; Steele-King, Clare; Gan, Yinbo; McQueen-Mason, Simon J

    2016-01-01

    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. PMID:27415441

  15. Rice Production and Marketing.

    ERIC Educational Resources Information Center

    Briers, Gary; Lee, Jasper S.

    This guide contains lesson plans for use in secondary programs of agricultural education in geographical areas in which rice is produced. Six units and 13 problem areas are organized into teaching plans that cover the broad nature of rice production. The six units are: (1) determining the importance and history of rice production; (2) determining…

  16. Effects of climate change on suitable rice cropping areas, cropping systems and crop water requirements in southern China

    DOE PAGESBeta

    Ye, Qing; Yang, Xiaoguang; Dai, Shuwei; Chen, Guangsheng; Li, Yong; Zhang, Caixia

    2015-06-05

    Here, we discuss that rice is one of the main crops grown in southern China. Global climate change has significantly altered the local water availability and temperature regime for rice production. In this study, we explored the influence of climate change on suitable rice cropping areas, rice cropping systems and crop water requirements (CWRs) during the growing season for historical (from 1951 to 2010) and future (from 2011 to 2100) time periods. The results indicated that the land areas suitable for rice cropping systems shifted northward and westward from 1951 to 2100 but with different amplitudes.

  17. Automorphogenesis and gravitropism of plant seedlings grown under microgravity conditions

    NASA Astrophysics Data System (ADS)

    Hoson, T.; Saiki, M.; Kamisaka, S.; Yamashita, M.

    Plant seedlings exhibit automorphogenesis on clinostats. The occurrence of automorphogenesis was confirmed under microgravity in Space Shuttle STS-95 flight. Rice coleoptiles showed an inclination toward the caryopsis in the basal region and a spontaneous curvature in the same adaxial direction in the elongating region both on a three-dimensional (3-D) clinostat and in space. Both rice roots and Arabidopsis hypocotyls also showed a similar morphology in space and on the 3-D clinostat. In rice coleoptiles, the mechanisms inducing such an automorphic curvature were studied. The faster-expanding convex side of rice coleoptiles showed a higher extensibility of the cell wall than the opposite side. Also, in the convex side, the cell wall thickness was smaller, the turnover of the matrix polysaccharides was more active, and the microtubules oriented more transversely than the concave side, and these differences appear to be causes of the curvature. When rice coleoptiles grown on the 3-D clinostat were placed horizontally, the gravitropic curvature was delayed as compared with control coleoptiles. In clinostatted coleoptiles, the corresponding suppression of the amyloplast development was also observed. Similar results were obtained in Arabidopsis hypocotyls. Thus, the induction of automorphogenesis and a concomitant decrease in graviresponsiveness occurred in plant shoots grown under microgravity conditions.

  18. Morphological Study of the Relationships between Weedy Rice Accessions (Oryza sativa Complex) and Commercial Rice Varieties in Pulau Pinang Rice Granary Area

    PubMed Central

    Hussain, Zainudin PMD; Man, Azmi; Othman, Ahmad Sofiman

    2010-01-01

    Weedy rice (WR) is found in many direct-seeded rice fields. WR possesses morphological characteristics that are similar to cultivated rice varieties in the early stage of growth, making them more difficult to control than other weeds. A comparative morphological study was conducted by collecting WR accessions from four sites within the Pulau Pinang rice growing areas. The objective of the study was to characterise WR accessions of the Pulau Pinang rice granary by comparing their morphological characteristics to those of commercially grown rice in the area. Their morphometric relations were established by comparing 17 morphological characteristics of the WR accessions and the commercial varieties. A total of 36 WR morphotypes were identified from these 4 sites based on 17 characteristics, which included grain shattering habit and germination rate. The Principal Component Analysis (PCA) showed that 45.88% of the variation observed among the WR accessions and commercial varieties were within the first 3 axes. PB6, PP2 and SGA5 WR accessions had a higher number of tillers and longer panicle lengths, culm heights and leaf lengths compared to the commercial rice. The grain sizes of the commercial varieties were slightly longer, and the chlorophyll contents at 60–70 days after sowing (DAS) were higher than those of the WR accessions. Results from this study are useful for predicting potential WR accession growth, which might improve WR management and agriculture practices that control WR in the future. PMID:24575197

  19. The role of irrigation techniques in arsenic bioaccumulation in rice (Oryza sativa L.).

    PubMed

    Spanu, Antonino; Daga, Leonardo; Orlandoni, Anna Maria; Sanna, Gavino

    2012-08-01

    The bioaccumulation of arsenic compounds in rice is of great concern worldwide because rice is the staple food for billions of people and arsenic is one of the most toxic and carcinogenic elements at even trace amounts. The uptake of arsenic compounds in rice comes mainly from its interaction with system soil/water in the reducing conditions typical of paddy fields and is influenced by the irrigation used. We demonstrate that the use of sprinkler irrigation produces rice kernels with a concentration of total arsenic about fifty times lower when compared to rice grown under continuous flooding irrigation. The average total amount of arsenic, measured by a fully validated ICP-MS method, in 37 rice grain genotypes grown with sprinkler irrigation was 2.8 ± 2.5 μg kg(-1), whereas the average amount measured in the same genotypes grown under identical conditions, but using continuous flooding irrigation was 163 ± 23 μg kg(-1). In addition, we find that the average concentration of total arsenic in rice grains cultivated under sprinkler irrigation is close to the total arsenic concentration found in irrigation waters. Our results suggest that, in our experimental conditions, the natural bioaccumulation of this element in rice grains may be completely circumvented by adopting an appropriate irrigation technique. PMID:22765219

  20. KINETIC PROPERTIES OF MALIC DEHYDROGENASE FROM THREE CULTIVARS OF RICE

    EPA Science Inventory

    Temperature induced changes in the kinetics of the enzyme malic dehydrogenase (MON) were investigated in three cultivars of rice(Oryza sativa L.). Cultivars, included IR74, SWAT2, and N22. Plants were grown in a controlled environment chamber for 29 days, at 31 degrees C day/25 d...

  1. Extraction of light filth from rice flours, extruded rice products, and rice paper: collaborative study.

    PubMed

    Dent, R G

    1982-09-01

    Two new methods were developed for the extraction of rodent hairs and insect fragments from rice products: one for rice flour and one for extruded rice products and rice paper. A 100 g sample of rice flour was extracted with mineral oil-40% isopropanol, followed by a water phase as needed for additional cycles. For extruded rice products and rice paper, a 225 g sample of each was initially extracted as above, followed by a single extraction with mineral oil-20% isopropanol. Both methods used an acid hydrolysis pretreatment followed by wet sieving and a percolator extraction. Average rodent hair recoveries were 77.8% for rice flour and 82.2% for extruded rice products and rice paper. Average insect fragment recoveries were 89.6% for rice flour and 91.9% for extruded rice products and rice paper. Both methods were adopted official first action. PMID:7130079

  2. Cooked rice texture and rice flour pasting properties; impacted by rice temperature during milling.

    PubMed

    Saleh, Mohammed; Meullenet, Jean-Francois

    2015-03-01

    Rice milling plays a key factor in determining rice quality and value. Therefore accurate quality assessments are critical to the rice industry. This study was undertaken to assess the effect of exposing rice to elevated temperatures during milling, on cooked rice texture and rice flour pasting properties. Two long (Cybonnett and Francis) and one medium (Jupiter) rice (oryzae sativa L.) cultivars were milled using McGill laboratory mill for 30 and 40 s after warmed up the mill before milling. Four different milling temperatures per milling duration were achieved. Cooked rice texture properties were assessed using a uniaxial compression test and rice flour pasting properties measured using a TA-2000 rheometer. Results of this study showed that exposure of rice to high temperatures during milling significantly decreased cooked rice firmness. An increase in milled rice temperature after milling from 10.0 to 13.3 °C resulted in a 5.4 and 8.1 N decrease in cooked rice firmness. Although not always significant, the increase in milled rice temperature during milling resulted in an increase in cooked rice stickiness. The increase in milling temperature also showed significant increase in rice flour pasting properties. Changes in rice functional characteristics were attributed to the changes occurring to rice chemical constituents due to temperature exposure as indicated by the increase in rice protein hydrophobicity. Proteins are known to affect rice starch water holding capacity and other starch gelatinization properties. PMID:25745230

  3. Selenium Characterization in the Global Rice Supply Chain

    SciTech Connect

    Williams, Paul N.; Lombi, Enzo; Sun, Guo-Xin; Scheckel, Kirk; Zhu, Yong-Guan; Feng, Xinbin; Zhu, Jianming; Carey, Anne-Marie; Adomako, Eureka; Lawgali, Youseff; Deacon, Claire; Meharg, Andrew A.

    2009-08-13

    For up to 1 billion people worldwide, insufficient dietary intake of selenium (Se) is a serious health constraint. Cereals are the dominant Se source for those on low protein diets, as typified by the global malnourished population. With crop Se content constrained largely by underlying geology, regional soil Se variations are often mirrored by their locally grown staples. Despite this, the Se concentrations of much of the world's rice, the mainstay of so many, is poorly characterized, for both total Se content and Se speciation. In this study, 1092 samples of market sourced polished rice were obtained. The sampled rice encompassed dominant rice producing and exporting countries. Rice from the U.S. and India were found to be the most enriched, while mean average levels were lowest in Egyptian rice: {approx}32-fold less than their North American equivalents. By weighting country averages by contribution to either global production or export, modeled baseline values for both were produced. Based on a daily rice consumption of 300 g day{sup -1}, around 75% of the grains from the production and export pools would fail to provide 70% of daily recommended Se intakes. Furthermore, Se localization and speciation characterization using X-ray fluorescence ({mu}-XRF) and X-ray absorption near edge structure ({mu}-XANES) techniques were investigated in a Se-rich sample. The results revealed that the large majority of Se in the endosperm was present in organic forms.

  4. Lack of Zn inhibition of Cd accumulation by rice (Oryza sativa L.) supports non-Zn transporter uptake of Cd

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice (Oryza sativa L.) grown on Cd contaminated soils has been linked to health problems in subsistence rice farmers in Japan and China. For other crops, normal geogenic Zn inhibits the increased uptake of Cd on contaminated soils. A study was conducted using a multi-chelator buffered nutrient sol...

  5. Validation of rice blast resistance genes in barley using a QTL mapping population and near-isolines.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are prior reports of Pyricularia grisea – the causal agent of blast of rice – causing disease in barley. In order to determine the specificity of this resistance in barley, we extended our previous mapping efforts to include blast isolates from barley and rice grown in Thailand and we assesse...

  6. Influence of Growth Temperature on the Amounts of Tocopherols, Tocotrienols, and y-Oryzanol in Brown Rice.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brown rice is a valuable source of lipid-soluble antioxidants including ferulated phytosterols (i.e., gamma-oryzanol), tocopherols, and tocotrienols. To evaluate the impact of temperature on the accumulation of these compounds, we analyzed seeds from 6 different rice lines grown to maturity in repli...

  7. Rice (Oryza sativa L.) containing the bar gene is compositionally equivalent to the nontransgenic counterpart.

    PubMed

    Oberdoerfer, Regina B; Shillito, Raymond D; de Beuckeleer, Marc; Mitten, Donna H

    2005-03-01

    This publication presents an approach to assessing compositional equivalence between grain derived from glufosinate-tolerant rice grain, genetic event LLRICE62, and its nontransgenic counterpart. Rice was grown in the same manner as is common for commercial production, using either conventional weed control practices or glufosinate-ammonium herbicide. A two-season multisite trial design provided a robust data set to evaluate environmental effects between the sites. Statistical comparisons to test for equivalence were made between glufosinate-tolerant rice and a conventional counterpart variety. The key nutrients, carbohydrates, protein, iron, calcium, thiamin, riboflavin, and niacin, for which rice can be the principal dietary source, were investigated. The data demonstrate that rice containing the genetic locus LLRICE62 has the same nutritional value as its nontransgenic counterpart, and most results for nutritional components fall within the range of values reported for rice commodities in commerce. PMID:15740024

  8. Suppression of Magnaporthe oryzae and interaction between Bacillus subtilis and rice plants in the control of rice blast.

    PubMed

    Sha, Yuexia; Wang, Qi; Li, Yan

    2016-01-01

    Magnaporthe oryzae, the causative pathogen of rice blast, has caused extensive losses to rice cultivation worldwide. Strains of the bacterium Bacillus subtilis have been used as biocontrol agents against rice blast. However, little has been reported about the interaction between B. subtilis and the rice plant and its mechanism of action. Here, the colonization process and induced disease resistance by B. subtilis SYX04 and SYX20 in rice plants was examined. Strains of B. subtilis labeled with green fluorescent protein reached population of more than 5 × 10(6) CFU/g after 20 days on mature rice leaves and were detected after 3 days on newly grown leaves. Results showed that SYX04 and SYX20 not only inhibited spore germination, germ tube length, and appressorial formation but also caused a series of alterations in the structures of hyphae and conidia. The cell walls and membrane structures of the fungus showed ultrastructural abnormalities, which became severely degraded as observed through scanning electron microscopy and transmission electron microscopy. The mixture of both B. subtilis and M. oryzae resulted in enhanced activity of peroxidase, and polyphenol oxidase while there was significantly more superoxide dismutase activity in plants that had been sprayed with B. subtilis alone. The present study suggests that colonized SYX04 and SYX20 strains protected rice plants and exhibited antifungal activity and induced systemic resistance, thus indicating their potential biological control agents. PMID:27536521

  9. Energy from rice residues

    SciTech Connect

    Mahin, D.B.

    1990-03-01

    Developing countries produce millions of tons of rice husks and straw as a byproduct of harvesting rice. Although some of these rice residues are used for fuel or other purposes, most are burned for disposal or just dumped. However, since the mid- 1980's, industrial plants for rice residue utilization have been installed in several countries and are planned in a number of others. The report provides information on systems to produce energy from rice residues that are commercially available in the United States, Europe, and various developing countries, with an emphasis on those currently used or sold on an international level. Specifically reviewed are the use of rice husks to produce: (1) industrial process heat either directly from furnaces or by generating low pressure steam in boilers; (2) mechanical and electrical power for rice milling via steam engine systems, steam turbine/generator systems, and gasifier/engine systems; and (3) electric power for the grid. The outlook for producing energy from rice straw is also assessed. In addition, the prospects for the use of energy from husks or straw in the processing of rice bran are reviewed.

  10. Determinants for grading Malaysian rice

    NASA Astrophysics Data System (ADS)

    ChePa, Noraziah; Yusoff, Nooraini; Ahmad, Norhayati

    2016-08-01

    Due to un-uniformity of rice grading practices in Malaysia, zones which actively producing rice in Malaysia are using their own way of grading rice. Rice grading is important in determining rice quality and its subsequent price in the market. It is an important process applied in the rice production industry with the purpose of ensuring that the rice produced for the market meets the quality requirements of consumer. Two important aspects that need to be considered in determining rice grades are grading technique and determinants to be used for grading (usually referred as rice attributes). This article proposes the list of determinants to be used in grading Malaysian rice. Determinants were explored through combination of extensive literature review and series of interview with the domain experts and practitioners. The proposed determinants are believed to be beneficial to BERNAS in improving the current Malaysian rice grading process.

  11. Spotlight on rice: an update from the Rice Division

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This short paper is a 'spotlight' on the Rice Division of the Marican Association of Cereal Chemists, International and features an update and future challenges in rice research and industry. Since rice is consumed largely as milled white rice intact kernals, size, shape, color, appearance, function...

  12. Golden Rice is an effective source of vitamin A1234

    PubMed Central

    Qin, Jian; Dolnikowski, Gregory G; Russell, Robert M; Grusak, Michael A

    2009-01-01

    Background: Genetically engineered “Golden Rice” contains up to 35 μg β-carotene per gram of rice. It is important to determine the vitamin A equivalency of Golden Rice β-carotene to project the potential effect of this biofortified grain in rice-consuming populations that commonly exhibit low vitamin A status. Objective: The objective was to determine the vitamin A value of intrinsically labeled dietary Golden Rice in humans. Design: Golden Rice plants were grown hydroponically with heavy water (deuterium oxide) to generate deuterium-labeled [2H]β-carotene in the rice grains. Golden Rice servings of 65–98 g (130–200 g cooked rice) containing 0.99–1.53 mg β-carotene were fed to 5 healthy adult volunteers (3 women and 2 men) with 10 g butter. A reference dose of [13C10]retinyl acetate (0.4–1.0 mg) in oil was given to each volunteer 1 wk before ingestion of the Golden Rice dose. Blood samples were collected over 36 d. Results: Our results showed that the mean (±SD) area under the curve for the total serum response to [2H]retinol was 39.9 ± 20.7 μg·d after the Golden Rice dose. Compared with that of the [13C10]retinyl acetate reference dose (84.7 ± 34.6 μg·d), Golden Rice β-carotene provided 0.24–0.94 mg retinol. Thus, the conversion factor of Golden Rice β-carotene to retinol is 3.8 ± 1.7 to 1 with a range of 1.9–6.4 to 1 by weight, or 2.0 ± 0.9 to 1 with a range of 1.0–3.4 to 1 by moles. Conclusion: β-Carotene derived from Golden Rice is effectively converted to vitamin A in humans. This trial was registered at clinicaltrials.gov as NCT00680355. PMID:19369372

  13. Rice (Oryza) hemoglobins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice (Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a sin...

  14. Registration of 'Cybonnet' Rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Cybonnet’ rice is a high-yielding, short-season, long-grain cultivar. It originated form the cross ‘Cypress’//’Newbonnet’/’Katy’ made at the University of Arkansas Rice Research and Extension Center in Stuttgart, AR. Cybonnet is similar in maturity to ‘Kaybonnet’ and ‘Wells’, is a simidwarf culti...

  15. Making rice even healthier!

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is a naturally healthy food, but what if it could be made even healthier? Would Americans eat more rice if it could be advertised to be a 'New and Improved' source of calcium to promote bone growth, or iron to prevent anemia? Grocery stores are full of foods that are vitamin enhanced to attract...

  16. Registration of 'Medark' Rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Medark’ rice is a high-yielding, early maturing, semidwarf, medium-grain cultivar. It originated from the cross ‘Bengal’/’Short Rico’ and is similar in maturity to Bengal. It has improved disease resistance to rice blase, brown spot and straighthead. Medark has a lodging resistance slightly less...

  17. Physiological and Morphological Responses of Ischaemum rugosum Salisb. (Wrinkled Grass) to Different Nitrogen Rates and Rice Seeding Rates

    PubMed Central

    Awan, Tahir Hussain; Chauhan, Bhagirath Singh; Cruz, Pompe C. Sta.

    2014-01-01

    Ischaemum rugosum is a competitive weed in direct-seeded rice systems. Developing integrated weed management strategies that promote the suppression of weeds by crop density, cultivar selection, and nutrition requires better understanding of the extent to which rice interferes with the growth of this weed and how it responds to resource limitation due to rice interference. The growth of I. rugosum was studied when grown with four rice seeding rates (0, 25, 50, and 100 kg ha−1) and four nitrogen (N) rates (0, 50, 100, and 150 kg ha−1). Compared to the weed plants grown alone, weed tiller number was reduced by 63–80%, leaf number by 68–77%, leaf area by 69–77%, leaf biomass by 72–84%, and inflorescence biomass by 81–93% at the rice seeding rates of 25–100 kg ha−1. All these parameters increased with increasing rates of N from 0 to 150 kg ha−1. At weed maturity, I. rugosum plants were 100% taller than rice at 0 kg N ha−1, whereas, with added N, the weeds were only 50% taller than rice. Weed biomass increased by 82–160%, whereas rice biomass increased by 92–229%, with the application of 50–150 kg N ha−1. Added N favored rice biomass production more than it did the weed. Rice interference reduced the height and biomass of I. rugosum, but did not suppress its growth completely. I. rugosum showed the ability to reduce the effects of rice interference by increasing leaf area, leaf weight ratio, and specific leaf area, and by decreasing the root-shoot weight ratio in comparison to the weed plants grown alone. The results suggest that rice crop interference alone may reduce I. rugosum growth but may not provide complete control of this weed. The need for integrated weed management practices to effectively control this weed species is highlighted. PMID:24910995

  18. Physiological and morphological responses of Ischaemum rugosum Salisb. (wrinkled grass) to different nitrogen rates and rice seeding rates.

    PubMed

    Awan, Tahir Hussain; Chauhan, Bhagirath Singh; Cruz, Pompe C Sta

    2014-01-01

    Ischaemum rugosum is a competitive weed in direct-seeded rice systems. Developing integrated weed management strategies that promote the suppression of weeds by crop density, cultivar selection, and nutrition requires better understanding of the extent to which rice interferes with the growth of this weed and how it responds to resource limitation due to rice interference. The growth of I. rugosum was studied when grown with four rice seeding rates (0, 25, 50, and 100 kg ha(-1)) and four nitrogen (N) rates (0, 50, 100, and 150 kg ha(-1)). Compared to the weed plants grown alone, weed tiller number was reduced by 63-80%, leaf number by 68-77%, leaf area by 69-77%, leaf biomass by 72-84%, and inflorescence biomass by 81-93% at the rice seeding rates of 25-100 kg ha(-1). All these parameters increased with increasing rates of N from 0 to 150 kg ha(-1). At weed maturity, I. rugosum plants were 100% taller than rice at 0 kg N ha(-1), whereas, with added N, the weeds were only 50% taller than rice. Weed biomass increased by 82-160%, whereas rice biomass increased by 92-229%, with the application of 50-150 kg N ha(-1). Added N favored rice biomass production more than it did the weed. Rice interference reduced the height and biomass of I. rugosum, but did not suppress its growth completely. I. rugosum showed the ability to reduce the effects of rice interference by increasing leaf area, leaf weight ratio, and specific leaf area, and by decreasing the root-shoot weight ratio in comparison to the weed plants grown alone. The results suggest that rice crop interference alone may reduce I. rugosum growth but may not provide complete control of this weed. The need for integrated weed management practices to effectively control this weed species is highlighted. PMID:24910995

  19. Rice blast disease in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is an important agricultural commodity in Texas, with an economic impact of more than $1 billion annually. Rice blast, caused by Magnaporthe oryzae, is one of the most devastating diseases in rice. Texas Rice Belt provides a warm, humid climate favorable for the infection and reproduction of M....

  20. Rice and red rice interference. II. Rice response to population densities of three red rice (Oryza sativa) ecotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice, which grows taller and produces more tillers than domestic rice and shatters most of its seeds early, is a major weed in many rice-growing areas of the world. Field experiments were conducted at Stuttgart, AR in 1997 and 1998 to evaluate the growth response of the Kaybonnet (KBNT) rice cul...

  1. 7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice. (See also Â... classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice...) (percent) Chalky kernels 1,2 In long grain rice (percent) In medium or short grain rice (percent)...

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

    PubMed

    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. PMID:25547964

  3. Proposal of a growth chamber for growing Super-Dwarf Rice in Space Agriculture

    NASA Astrophysics Data System (ADS)

    Hirai, Hiroaki; Kitaya, Yoshiaki; Tsukamoto, Koya; Yamashita, Youichirou; Hirai, Takehiro

    Space agriculture needs to be considered to supply food for space crew who stay in space over an extended time period. So far crops such as wheat, onion, oat, pea and lettuce grew to explore the possibility of space agriculture. Although rice is a staple food for most of the world, research on rice cultivation in space has not been done much. Rice grains are nutrient-rich with carbohydrate, protein and dietary fiber. Moreover, rice is a high yield crop and harvested grains have a long shelf life. However, the plant height of standard rice cultivars is relatively long, requiring much space. In addition, rice plants require higher light intensities for greater yield. For these reasons, it is difficult to establish facilities for rice culture in a limited space with a low cost. We propose to employee a super-dwarf cultivar and a small growth chamber with a new type of LEDs. The super-dwarf rice is a short-grain japonica variety and the plant height is approximately 20 cm that is one-fifth as tall as standard cultivars. The LED light used as a light source for this study can provide full spectrum of 380 nm to 750 nm. Air temperature and humidity were controlled by a Peltier device equipped in the chamber. The characteristics of the new type of LEDs and other equipments of the chamber and the ground based performance of super-dwarf rice plants grown in the chamber will be reported.

  4. Are Symbiotic Methanotrophs Key Microbes for N Acquisition in Paddy Rice Root?

    PubMed

    Minamisawa, Kiwamu; Imaizumi-Anraku, Haruko; Bao, Zhihua; Shinoda, Ryo; Okubo, Takashi; Ikeda, Seishi

    2016-03-26

    The relationships between biogeochemical processes and microbial functions in rice (Oryza sativa) paddies have been the focus of a large number of studies. A mechanistic understanding of methane-nitrogen (CH4-N) cycle interactions is a key unresolved issue in research on rice paddies. This minireview is an opinion paper for highlighting the mechanisms underlying the interactions between biogeochemical processes and plant-associated microbes based on recent metagenomic, metaproteomic, and isotope analyses. A rice symbiotic gene, relevant to rhizobial nodulation and mycorrhization in plants, likely accommodates diazotrophic methanotrophs or the associated bacterial community in root tissues under low-N fertilizer management, which may permit rice plants to acquire N via N2 fixation. The amount of N fixed in rice roots was previously estimated to be approximately 12% of plant N based on measurements of (15)N natural abundance in a paddy field experiment. Community analyses also indicate that methanotroph populations in rice roots are susceptible to environmental conditions such as the microclimate of rice paddies. Therefore, CH4 oxidation by methanotrophs is a driving force in shaping bacterial communities in rice roots grown in CH4-rich environments. Based on these findings, we propose a hypothesis with unanswered questions to describe the interplay between rice plants, root microbiomes, and their biogeochemical functions (CH4 oxidation and N2 fixation). PMID:26960961

  5. Are Symbiotic Methanotrophs Key Microbes for N Acquisition in Paddy Rice Root?

    PubMed Central

    Minamisawa, Kiwamu; Imaizumi-Anraku, Haruko; Bao, Zhihua; Shinoda, Ryo; Okubo, Takashi; Ikeda, Seishi

    2016-01-01

    The relationships between biogeochemical processes and microbial functions in rice (Oryza sativa) paddies have been the focus of a large number of studies. A mechanistic understanding of methane–nitrogen (CH4–N) cycle interactions is a key unresolved issue in research on rice paddies. This minireview is an opinion paper for highlighting the mechanisms underlying the interactions between biogeochemical processes and plant-associated microbes based on recent metagenomic, metaproteomic, and isotope analyses. A rice symbiotic gene, relevant to rhizobial nodulation and mycorrhization in plants, likely accommodates diazotrophic methanotrophs or the associated bacterial community in root tissues under low-N fertilizer management, which may permit rice plants to acquire N via N2 fixation. The amount of N fixed in rice roots was previously estimated to be approximately 12% of plant N based on measurements of 15N natural abundance in a paddy field experiment. Community analyses also indicate that methanotroph populations in rice roots are susceptible to environmental conditions such as the microclimate of rice paddies. Therefore, CH4 oxidation by methanotrophs is a driving force in shaping bacterial communities in rice roots grown in CH4-rich environments. Based on these findings, we propose a hypothesis with unanswered questions to describe the interplay between rice plants, root microbiomes, and their biogeochemical functions (CH4 oxidation and N2 fixation). PMID:26960961

  6. Engineering analysis of ERTS data for rice in the Philippines

    NASA Technical Reports Server (NTRS)

    Mcnair, A. J. (Principal Investigator); Heydt, H. L.

    1973-01-01

    The author has identified the following significant results. Rice is an important food worldwide. Worthwhile goals, particularly for developing nations, are the capability to recognize from satellite imagery: (1) areas where rice is grown, and (2) growth status (irrigation, vigor, yield). A two-step procedure to achieve this is being investigated. Ground truth, and ERTS-1 imagery (four passes) covering 80% of a rice growth cycle for some Philippine sites, have been analyzed. One-D and three-D signature extraction, and synthesis of an initial site recognition/status algorithm have been performed. Results are encouraging. but additional passes and sites must be analyzed. Good position information for extracted data is a must.

  7. Anaerobic conditions improve germination of a gibberellic acid deficient rice

    NASA Technical Reports Server (NTRS)

    Frantz, Jonathan M.; Bugbee, Bruce

    2002-01-01

    Dwarf plants are useful in research because multiple plants can be grown in a small area. Rice (Oryza sativa L.) is especially important since its relatively simple genome has recently been sequenced. We are characterizing a gibberellic acid (GA) mutant of rice (japonica cv 'Shiokari,' line N-71) that is extremely dwarf (20 cm tall). Unfortunately, this GA mutation is associated with poor germination (70%) under aerobic conditions. Neither exogenous GA nor a dormancy-breaking heat treatment improved germination. However, 95% germination was achieved by germinating the seeds anaerobically, either in a pure N2 environment or submerged in unstirred tap water. The anaerobic conditions appear to break a mild post-harvest dormancy in this rice cultivar. Copyright 2002 Crop Science Society of America.

  8. Arbuscular mycorrhizal fungi reduced the ratios of inorganic/organic arsenic in rice grains.

    PubMed

    Li, H; Chen, X W; Wong, M H

    2016-02-01

    Arbuscular mycorrhizal fungi (AMF) - Rhizophagus intraradices was inoculated to rice to investigate its effects on arsenic (As) uptake, grain As speciation, and rhizospheric As concentration of six rice cultivars grown in As-amended soil (60 mg As kg(-1) soil). The AMF inoculation induced either positive, neutral or negative responses in rice grown in As contaminated soil, suggesting that functional diversity may exist in AMF symbiosis when As is taken up and transferred. The ratios of inorganic/organic As concentrations in rice grains of all cultivars were significantly reduced by AMF, that involved the transformation of inorganic As into less toxic organic form dimethylarsinic acid (DMA) in rice. AMF decreased significantly total As and inorganic As concentrations in rice grains of Handao 3. Positive correlations (R(2) = 0.30-0.56, P < 0.05) between As in the rhizospheric soil solution and As in rice grain at different periods were observed. This inferred that the As survey of soil solution can be an effective measure for evaluating As in grains. PMID:26688259

  9. Identification and functional analysis of light-responsive unique or paralogous gene family members in rice using a near genomic gene microarray

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using a NSF45K-gene-microarray, we performed expression-profiling experiments on 2-week-old light- and dark-grown rice leaf tissue to identify mutants of light-responsive genes. We identified 356 genes that were at least 8-fold light induced genes at FDR of 1.00E-06. Then, we screened rice T-DNA i...

  10. Reduction in uptake by rice and soybean of aromatic arsenicals from diphenylarsinic acid contaminated soil amended with activated charcoal.

    PubMed

    Arao, Tomohito; Maejima, Yuji; Baba, Koji

    2011-10-01

    Activated charcoal (AC) amendment has been suggested as a promising method to immobilize organic contaminants in soil. We performed pot experiments with rice and soybean grown in agricultural soil polluted by aromatic arsenicals (AAs). The most abundant AA in rice grains and soybean seeds was methylphenylarsinic acid (MPAA). MPAA concentration in rice grains was significantly reduced to 2% and 3% in 0.2% AC treated soil compared to untreated soil in the first year of rice cultivation. In the second year, MPAA concentration in rice grains was significantly reduced to 15% in 0.2% AC treated soil compared to untreated soil. MPAA concentration in soybean seeds was significantly reduced to 44% in 0.2% AC treated soil compared to untreated soil. AC amendment was effective in reducing AAs in rice and soybean. PMID:21782301

  11. Resequencing rice genomes: an emerging new era of rice genomics.

    PubMed

    Huang, Xuehui; Lu, Tingting; Han, Bin

    2013-04-01

    Rice is a model system for crop genomics studies. Much of the early work on rice genomics focused on analyzing genome-wide genetic variation to further understand rice gene functions in agronomic traits and to generate data and resources for rice research. The advent of next-generation high-throughput DNA sequencing technologies and the completion of high-quality reference genome sequences have enabled the development of sequencing-based genotyping and genome-wide association studies (GWAS) that have significantly advanced rice genetics research. This has led to the emergence of a new era of rice genomics aimed at bridging the knowledge gap between genotype and phenotype in rice. These technologies have also led to pyramid breeding through genomics-assisted selection, which will be useful in breeding elite varieties suitable for sustainable agriculture. Here, we review the recent advances in rice genomics and discuss the future of this line of research. PMID:23295340

  12. Photoperiod shift effects on yield characteristics of rice.

    PubMed

    Volk, G M; Mitchell, C A

    1995-01-01

    Edible yield must be maximized for each crop species selected for inclusion in the Controlled Ecological Life-Support System (CELSS) proposed by NASA to support long-term manned space missions. In a greenhouse study aimed at increasing biomass partitioning to rice (Oryza sativa L.) grain, plants of the high yielding semi-dwarf rice cultivar Ai-Nan-Tsao were started in pots under 8-h photoperiods at a density of 212 plants m-2. After different periods of time under 8-h photoperiods, pots were switched to continuous light for the remainder of the cropping cycle. Continuous light did not delay time to first panicle emergence (60 d) or time to harvest (83 d). There was a positive correlation between the length of continuous light treatments and nongrain biomass. Grain yield (1.6 +/- 0.2 g plant-1) did not increase in continuous light. Yield-efficiency rate (grain weight per length of cropping cycle, canopy volume, and weight of nongrain shoot biomass) was used to compare treatments. Small Ai-Nan-Tsao rice canopies grown under 8-h photoperiods were more efficient producers of grain than canopies grown under continuous light for a portion of the rice cropping cycle. PMID:11540306

  13. Photoperiod shift effects on yield characteristics of rice

    NASA Technical Reports Server (NTRS)

    Volk, G. M.; Mitchell, C. A.

    1995-01-01

    Edible yield must be maximized for each crop species selected for inclusion in the Controlled Ecological Life-Support System (CELSS) proposed by NASA to support long-term manned space missions. In a greenhouse study aimed at increasing biomass partitioning to rice (Oryza sativa L.) grain, plants of the high yielding semi-dwarf rice cultivar Ai-Nan-Tsao were started in pots under 8-h photoperiods at a density of 212 plants m-2. After different periods of time under 8-h photoperiods, pots were switched to continuous light for the remainder of the cropping cycle. Continuous light did not delay time to first panicle emergence (60 d) or time to harvest (83 d). There was a positive correlation between the length of continuous light treatments and nongrain biomass. Grain yield (1.6 +/- 0.2 g plant-1) did not increase in continuous light. Yield-efficiency rate (grain weight per length of cropping cycle, canopy volume, and weight of nongrain shoot biomass) was used to compare treatments. Small Ai-Nan-Tsao rice canopies grown under 8-h photoperiods were more efficient producers of grain than canopies grown under continuous light for a portion of the rice cropping cycle.

  14. A study on the susceptibility of rice cultivars to Striga hermonthica and mapping of Striga tolerance quantitative trait loci in rice.

    PubMed

    Kaewchumnong, Krittika; Price, Adam H

    2008-01-01

    Striga is a parasitic weed attacking mainly maize, sorghum, millet and cowpea. Studying the interaction between rice and Striga is valuable since rice is a model monocot. In this paper, the susceptibility of different rice cultivars to S. hermonthica was tested and quantitative trait loci (QTL) for Striga tolerance mapped on the Bala x Azucena F(6) population. Seven rice cultivars were grown with and without S. hermonthica for 14 wk. For the mapping experiment, 115 recombinant inbred lines (RILs), along with Azucena and Bala, were grown with and without Striga for 11 wk. Rice cultivars tested had different susceptibilities to Striga, ranging from highly susceptible to completely resistant. Azucena and Bala differed in the speed of Striga emergence and the impact on host growth. A genomic region between positions 139 and 166 cM on chromosome 1 was identified containing strong QTL (LOD = 4.9-15.7) for all traits measured. This indicates that genes for Striga tolerance exist in rice germplasm and the mapped QTL can be further studied to promote understanding of the nature of resistance/tolerance and breeding for Striga-resistant crop plants. PMID:18657212

  15. Sulfur Fertilization Changes the Community Structure of Rice Root-, and Soil- Associated Bacteria

    PubMed Central

    Masuda, Sachiko; Bao, Zhihua; Okubo, Takashi; Sasaki, Kazuhiro; Ikeda, Seishi; Shinoda, Ryo; Anda, Mizue; Kondo, Ryuji; Mori, Yumi; Minamisawa, Kiwamu

    2016-01-01

    Under paddy field conditions, biological sulfur oxidation occurs in the oxidized surface soil layer and rhizosphere, in which oxygen leaks from the aerenchyma system of rice plants. In the present study, we examined community shifts in sulfur-oxidizing bacteria associated with the oxidized surface soil layer and rice roots under different sulfur fertilization conditions based on the 16S ribosomal RNA (rRNA) gene in order to explore the existence of oligotrophic sulfur-oxidizing bacteria in the paddy rice ecosystem. Rice plants were grown in pots with no fertilization (control) or CaCO3 or CaSO4 fertilization. A principal-coordinates analysis (PCoA) showed that CaSO4 fertilization markedly affected bacterial communities associated with rice roots and soil, whereas no significant differences were observed in plant growth among the fertilizer treatments examined. In rice roots, the relative abundance of Acidobacteria, Alphaproteobacteria, Gammaproteobacteria, and TM7 was significantly higher in CaSO4-fertilized pots than in control pots. Alphaproteobacteria, Bradyrhizobiaceae, and Methylocystaceae members were significantly more abundant in CaSO4-fertilized roots than in control roots. On the other hand, the abundance of Actinobacteria and Proteobacteria was lower in CaSO4-fertilized soil than in control soil. These results indicate that the bacteria associated with rice roots and soil responded to the sulfur amendment, suggesting that more diverse bacteria are involved in sulfur oxidation in the rice paddy ecosystem than previously considered. PMID:26947443

  16. Sulfur Fertilization Changes the Community Structure of Rice Root-, and Soil- Associated Bacteria.

    PubMed

    Masuda, Sachiko; Bao, Zhihua; Okubo, Takashi; Sasaki, Kazuhiro; Ikeda, Seishi; Shinoda, Ryo; Anda, Mizue; Kondo, Ryuji; Mori, Yumi; Minamisawa, Kiwamu

    2016-03-26

    Under paddy field conditions, biological sulfur oxidation occurs in the oxidized surface soil layer and rhizosphere, in which oxygen leaks from the aerenchyma system of rice plants. In the present study, we examined community shifts in sulfur-oxidizing bacteria associated with the oxidized surface soil layer and rice roots under different sulfur fertilization conditions based on the 16S ribosomal RNA (rRNA) gene in order to explore the existence of oligotrophic sulfur-oxidizing bacteria in the paddy rice ecosystem. Rice plants were grown in pots with no fertilization (control) or CaCO3 or CaSO4 fertilization. A principal-coordinates analysis (PCoA) showed that CaSO4 fertilization markedly affected bacterial communities associated with rice roots and soil, whereas no significant differences were observed in plant growth among the fertilizer treatments examined. In rice roots, the relative abundance of Acidobacteria, Alphaproteobacteria, Gammaproteobacteria, and TM7 was significantly higher in CaSO4-fertilized pots than in control pots. Alphaproteobacteria, Bradyrhizobiaceae, and Methylocystaceae members were significantly more abundant in CaSO4-fertilized roots than in control roots. On the other hand, the abundance of Actinobacteria and Proteobacteria was lower in CaSO4-fertilized soil than in control soil. These results indicate that the bacteria associated with rice roots and soil responded to the sulfur amendment, suggesting that more diverse bacteria are involved in sulfur oxidation in the rice paddy ecosystem than previously considered. PMID:26947443

  17. Characterization of functional trait diversity among Indian cultivated and weedy rice populations.

    PubMed

    Rathore, M; Singh, Raghwendra; Kumar, B; Chauhan, B S

    2016-01-01

    Weedy rice, a menace in rice growing areas globally, is biosimilar having attributes similar to cultivated and wild rice, and therefore is difficult to manage. A study was initiated to characterize the functional traits of 76 weedy rice populations and commonly grown rice cultivars from different agro-climatic zones for nine morphological, five physiological, and three phenological parameters in a field experiment under an augmented block design. Comparison between weedy and cultivated rice revealed a difference in duration (days) from panicle emergence to heading as the most variable trait and awn length as the least variable one, as evidenced from their coefficients of variation. The results of principal component analysis revealed the first three principal components to represent 47.3% of the total variation, which indicates an important role of transpiration, conductance, leaf-air temperature difference, days to panicle emergence, days to heading, flag leaf length, SPAD (soil-plant analysis development), grain weight, plant height, and panicle length to the diversity in weedy rice populations. The variations existing in weedy rice population are a major reason for its wider adaptability to varied environmental conditions and also a problem while trying to manage it. PMID:27072282

  18. Characterization of functional trait diversity among Indian cultivated and weedy rice populations

    PubMed Central

    Rathore, M.; Singh, Raghwendra; Kumar, B.; Chauhan, B. S.

    2016-01-01

    Weedy rice, a menace in rice growing areas globally, is biosimilar having attributes similar to cultivated and wild rice, and therefore is difficult to manage. A study was initiated to characterize the functional traits of 76 weedy rice populations and commonly grown rice cultivars from different agro-climatic zones for nine morphological, five physiological, and three phenological parameters in a field experiment under an augmented block design. Comparison between weedy and cultivated rice revealed a difference in duration (days) from panicle emergence to heading as the most variable trait and awn length as the least variable one, as evidenced from their coefficients of variation. The results of principal component analysis revealed the first three principal components to represent 47.3% of the total variation, which indicates an important role of transpiration, conductance, leaf-air temperature difference, days to panicle emergence, days to heading, flag leaf length, SPAD (soil-plant analysis development), grain weight, plant height, and panicle length to the diversity in weedy rice populations. The variations existing in weedy rice population are a major reason for its wider adaptability to varied environmental conditions and also a problem while trying to manage it. PMID:27072282

  19. Occurrence and partitioning of cadmium, arsenic and lead in mine impacted paddy rice: Hunan, China.

    PubMed

    Williams, Paul N; Lei, Ming; Sun, Guoxin; Huang, Qing; Lu, Ying; Deacon, Claire; Meharg, Andrew A; Zhu, Yong-Guan

    2009-02-01

    Paddy rice has been likened to nictiana sp in its ability to scavenge cadmium (Cd) from soil, whereas arsenic (As) accumulation is commonly an order of magnitude higher than in other cereal crops. In areas such as those found in parts of Hunan province in south central China, base-metal mining activities and rice farming coexist. Therefore there is a considerable likelihood that lead (Pb), in addition to Cd and As, will accumulate in rice grown in parts of this region above levels suitable for human consumption. To test this hypothesis, a widespread provincial survey of rice from mine spoilt paddies (n = 100), in addition to a follow-up market grain survey (n = 122) conducted in mine impacted areas was undertaken to determine the safety of local rice supply networks. Furthermore, a specific Cd, As, and Pb biogeochemical survey of paddy soil and rice was conducted within southern China, targeting sites impacted by mining of varying intensities to calibrate rice metal(loid) transfer models and transfer factors that can be used to predict tissue loading. Results revealed a number of highly significant correlations between shoot, husk, bran, and endosperm rice tissue fractions and that rice from mining areas was enriched in Cd, As, and Pb. Sixty-five, 50, and 34% of all the mine-impacted field rice was predicted to fail national food standards for Cd, As, and Pb, respectively. Although, not as elevated as the grains from the mine-impacted field survey, it was demonstrated that metal(loid) tainted rice was entering food supply chains intended for direct human consumption. PMID:19244995

  20. Water management affects arsenic and cadmium accumulation in different rice cultivars.

    PubMed

    Hu, Pengjie; Huang, Jiexue; Ouyang, Younan; Wu, Longhua; Song, Jing; Wang, Songfeng; Li, Zhu; Han, Cunliang; Zhou, Liqiang; Huang, Yujuan; Luo, Yongming; Christie, Peter

    2013-12-01

    Paddy rice (Oryza sativa L.) is a staple food and one of the major sources of dietary arsenic (As) and cadmium (Cd) in Asia. A field experiment was conducted to investigate the effects of four water management regimes (aerobic, intermittent irrigation, conventional irrigation and flooding) on As and Cd accumulation in seven major rice cultivars grown in Zhejiang province, east China. With increasing irrigation from aerobic to flooded conditions, the soil HCl-extractable As concentrations increased significantly and the HCl-extractable Cd concentrations decreased significantly. These trends were consistent with the As and Cd concentrations in the straw, husk and brown rice. Water management both before and after the full tillering stage affected As and Cd accumulation in the grains. The intermittent and conventional treatments produced higher grain yields than the aerobic and flooded treatments. Cd concentrations in brown rice varied 13.1-40.8 times and As varied 1.75-8.80 times among the four water management regimes. Cd and As accumulation in brown rice varied among the rice cultivars, with Guodao 6 (GD6) was a low Cd but high-As-accumulating cultivar while Indonesia (IR) and Yongyou 9 (YY9) were low As but high-Cd-accumulating cultivars. Brown rice Cd and As concentrations in the 7 cultivars were significantly negatively correlated. The results indicate that As and Cd accumulated in rice grains with opposite trends that were influenced by both water management and rice cultivar. Production of 'safe' rice with respect to As and Cd might be possible by balancing water management and rice cultivar according to the severity of soil pollution. PMID:23719663

  1. Arsenic hazard in Cambodian rice from a market-based survey with a case study of Preak Russey village, Kandal Province.

    PubMed

    Gilbert, Peter J; Polya, David A; Cooke, David A

    2015-08-01

    This study comprises a market-based survey to assess the arsenic (As) hazard of Cambodian rice, encompassing rice from seven Cambodian provinces, comparisons with rice imported from China, Vietnam and Thailand, and assessments of 15 rice varieties. Rice samples (n = 157) were collected from four large markets in Kandal Province and analysed for As using inductively coupled mass spectrometry. The mean As concentration for Cambodian rice (0.185 µg g(-1), range 0.047-0.771 µg g(-1)) was higher than that for imported rice from Vietnam and Thailand (0.162 and 0.157 µg g(-1), respectively) with mean As concentrations highest in rice from Prey Veng Province resulting in a daily dose of 1.77 µg kg(-1) b.w. (body weight) d(-1). Between unmilled rice varieties, Cambodian-grown White Sticky Rice had the highest mean As concentration (0.234 µg g(-1)), whilst White Sticky Rice produced in Thailand had the lowest (0.125 µg g(-1)), suggesting that localised conditions have greater bearing over rice As concentrations than differences in As uptake between individual varieties themselves. A rice and water consumption survey for 15 respondents in the village of Preak Russey revealed mean consumption rates of 522 g d(-1) of rice and 1.9 L d(-1) of water. At water As concentrations >1000 µg L(-1), the relative contribution to the daily dose from rice is low. When water As concentrations are lowered to 50 µg L(-1), daily doses from rice and water are both generally below the 3.0 µg kg(-1) b.w. d(-1) benchmark daily limit for a 0.5% increase in lung cancer, yet when combined they exceeded this value in all but three respondents. PMID:25893486

  2. Expressing ScACR3 in rice enhanced arsenite efflux and reduced arsenic accumulation in rice grains.

    PubMed

    Duan, Guilan; Kamiya, Takehiro; Ishikawa, Satoru; Arao, Tomohito; Fujiwara, Toru

    2012-01-01

    Arsenic (As) accumulation in rice grain poses a serious health risk to populations with high rice consumption. Extrusion of arsenite [As(III)] by ScAcr3p is the major arsenic detoxification mechanism in Saccharomyces cerevisiae. However, ScAcr3p homolog is absent in higher plants, including rice. In this study, ScACR3 was introduced into rice and expressed under the control of the Cauliflower mosaic virus (CaMV) 35S promoter. In the transgenic lines, As concentrations in shoots and roots were about 30% lower than in the wild type, while the As translocation factors were similar between transgenic lines and the wild type. The roots of transgenic plants exhibited significantly higher As efflux activities than those of the wild type. Within 24 h exposure to 10 μM arsenate [As(V)], roots of ScACR3-expressing plants extruded 80% of absorbed As(V) to the external solution as As(III), while roots of the wild type extruded 50% of absorbed As(V). Additionally, by exposing the As-containing rice plants to an As-lacking solution for 24 h, about 30% of the total As derived from pre-treatment was extruded to the external solution by ScACR3-expressing plants, while about 15% of As was extruded by wild-type plants. Importantly, ScACR3 expression significantly reduced As accumulation in rice straws and grains. When grown in flooded soil irrigated with As(III)-containing water, the As concentration in husk and brown rice of the transgenic lines was reduced by 30 and 20%, respectively, compared with the wild type. This study reports a potential strategy to reduce As accumulation in the food chain by expressing heterologous genes in crops. PMID:22107880

  3. Rice: Characterizing the Environmental Response of a Gibberellic Acid-Deficient Rice for Use as a Model Crop

    NASA Technical Reports Server (NTRS)

    Frantz, Jonathan M.; Pinnock, Derek; Klassen, Steve; Bugbee, Bruce

    2004-01-01

    Rice (Oryza sativa L.) is a useful model crop plant. Rice was the first crop plant to have its complete genome sequenced. Unfortunately, even semi-dwarf rice cultivars are 60 to 90 an tail, and large plant populations cannot be grown in the confined volumes of greenhouses and growth chambers. We recently identified an extremely short (20 em tall) rice line, which is an ideal model for larger rice cultivars. We called this line "Super Dwarf rice." Here we report the response of Super Dwarf to temperature, photoperiod, photosynthetic photon flux (PPF), and factors that can affect time to head emergence. Vegetative biomass increased 6% per degree Celsius, with increasing temperature from 27 to 31 C. Seed yield decreased by 2% per degree Celsius rise in temperature, and as a result, harvest index decreased from 60 to 54%. The time to heading increased by 2 d for every hour above a 12-h photoperiod. Yield increased with increasing PPF up to the highest level tested at 1800 micro-mol/sq m/s (12-h photoperiod; 77.8 mol/sq m/d). Yield efficiency (grams per mole of photons) increased to 900 micro-mol/sq m/s and then slightly decreased at 1800 micro-mol/sq m/s . Heading was delayed by addition of gibberellic acid 3 (GA,) to the root zone but was hastened under mild N stress. Overall, short stature, high yield, high harvest index, and no extraordinary environmental requirements make Super Dwarf rice an excellent model plant for yield studies in controlled environments.

  4. Effect of rice variety and nutrient management on rice productivity in organic rice system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Demand for organic rice has been increasing for decades. However, the information on sustainable organic rice production systems is still lacking. The objective of this study was to investigate the effects of soil amendment products, nitrogen rate, and variety on rice grain yield, yield components, ...

  5. Survey of arsenic and its speciation in rice products such as breakfast cereals, rice crackers and Japanese rice condiments.

    PubMed

    Sun, Guo-Xin; Williams, Paul N; Zhu, Yong-Guan; Deacon, Claire; Carey, Anne-Marie; Raab, Andrea; Feldmann, Joerg; Meharg, Andrew A

    2009-04-01

    Rice has been demonstrated to be one of the major contributors to arsenic (As) in human diets in addition to drinking water, but little is known about rice products as an additional source of As exposure. Rice products were analyzed for total As and a subset of samples were measured for arsenic speciation using high performance liquid chromatography interfaced with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). A wide range of rice products had total and inorganic arsenic levels that typified those found in rice grain including, crisped rice, puffed rice, rice crackers, rice noodles and a range of Japanese rice condiments as well as rice products targeted at the macrobiotic, vegan, lactose intolerant and gluten intolerance food market. Most As in rice products are inorganic As (75.2-90.1%). This study provides a wider appreciation of how inorganic arsenic derived from rice products enters the human diet. PMID:18775567

  6. RICE IDENTITY TESTING USING DNA MARKER ANALYSIS OF PROCESSEDOR ARCHIVED RICE TISSUE AND RICE-INGREDIENT FOODS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The highly regarded reputation of USA rice in the world marketplace rice has been achieved by delivering rice and rice products that meet rigorous standards of uniformity and quality. In this regard, seed dealers, farmers, millers, and processors are concerned that the rice seed they are handling is...

  7. Phytoremediation of arsenic contaminated paddy soils with Pteris vittata markedly reduces arsenic uptake by rice.

    PubMed

    Ye, Wen-Ling; Khan, M Asaduzzaman; McGrath, Steve P; Zhao, Fang-Jie

    2011-12-01

    Arsenic (As) accumulation in food crops such as rice is of major concern. To investigate whether phytoremediation can reduce As uptake by rice, the As hyperaccumulator Pteris vittata was grown in five contaminated paddy soils in a pot experiment. Over a 9-month period P. vittata removed 3.5-11.4% of the total soil As, and decreased phosphate-extractable As and soil pore water As by 11-38% and 18-77%, respectively. Rice grown following P. vittata had significantly lower As concentrations in straw and grain, being 17-82% and 22-58% of those in the control, respectively. Phytoremediation also resulted in significant changes in As speciation in rice grain by greatly decreasing the concentration of dimethylarsinic acid (DMA). In two soils the concentration of inorganic As in rice grain was decreased by 50-58%. The results demonstrate an effective stripping of bioavailable As from contaminated paddy soils thus reducing As uptake by rice. PMID:21840633

  8. Nitrogen uptake and use efficiency in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is a staple food for a large proportion of the world’s population. Most of the rice is produced and consumed in Asia. Rice is produced in both upland and lowland systems, with about 76% of the global rice produced from irrigated-lowland rice systems. Nitrogen (N) is one of the most important in...

  9. Rice disease management under organic production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in organic rice production has increased because of the increased market demand for organic rice. Texas organic rice acreage has constantly increased over the last decade, reaching 32,000 acres in 2012. Texas is now the leading state in organic rice production in the U.S. Organic rice is p...

  10. Graphic Grown Up

    ERIC Educational Resources Information Center

    Kim, Ann

    2009-01-01

    It's no secret that children and YAs are clued in to graphic novels (GNs) and that comics-loving adults are positively giddy that this format is getting the recognition it deserves. Still, there is a whole swath of library card-carrying grown-up readers out there with no idea where to start. Splashy movies such as "300" and "Spider-Man" and their…

  11. Determining the basis of nonhost resistance in rice to cereal rusts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cereal rusts are a constant disease threat that limits the production of almost all agricultural cereals. Rice is atypical in that it is an intensively grown agricultural cereal that is immune to rust pathogens. This immunity is manifested by nonhost resistance (NHR), the mechanisms of which are poo...

  12. INTRASPECIFIC VARIATION IN SENSITIVITY TO UV-B RADIATION IN RICE

    EPA Science Inventory

    Twenty-two cultivars of rice (Oryza sativa L.) from diverse origins were grown under greenhouse conditions and exposed to ultraviolet-B radiation (UV-B; 280-320 nm) simulating a 5% reduction in stratospheric ozone in spring for the Philippines (14 degrees N lat.) to evaluate grow...

  13. SUPPLEMENTAL ULTRAVIOLET-B RADIATION DOES NOT REDUCE GROWTH OR GRAIN YIELD IN RICE

    EPA Science Inventory

    Negative effects of enhanced UV-B radiation have been demonstrated in plants, but impacts under realistic field conditions remain uncertain. Adverse impacts to major crops, such as rice (Oryza sativa L.), that are grown in areas with currently high ambient levels of UV-B, could h...

  14. Reducing greenhouse gas emissions, water use and grain arsenic levels in rice systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture is faced with the challenge of providing healthy food for a growing population while minimizing environmental consequences. Rice (Oryza sativa), the staple crop for the largest number of people on earth, is grown under flooded soil conditions and uses more water and has higher greenhous...

  15. Comprehensive description for newly introduced accessions in the USDA rice germplasm collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New accessions are introduced to the USDA Plant Germplasm System (PGS) each year which requires characterization for key plant descriptors was well as seed increase for distribution to the public. In 2004, 1,412 rice accessions released from the APHIS Quarantine Program were grown out and characteri...

  16. Rice bacterial endophytes: isolation of a collection, identification of beneficial strains and microbiome analysis.

    PubMed

    Bertani, Iris; Abbruscato, Pamela; Piffanelli, Pietro; Subramoni, Sujatha; Venturi, Vittorio

    2016-06-01

    Endophytes are harmless or beneficial microorganisms that live inside plants between cells. The relationship they develop with the plant as well as their potential role in plant health is at large unexplored and it is believed that the opportunity to find new and interesting endophytes among the large variety of plants is great. Here, we present the isolation and analysis of a large collection of endophytes from one cultivar of rice grown in Italy. A total 1318 putative endophytes were isolated from roots, leaves and stems from rice grown in submerged and dry conditions and a working collection of 229 isolates was created. Among these, several isolates were confirmed to be endophytes and a few displayed the trait of plant growth promotion. A cultivation independent analysis via 16S rDNA amplicons of the bacterial community of the endosphere was also performed providing information on bacterial diversity in the rice endopshere. PMID:27038229

  17. Phytoremediation of the herbicides atrazine and metolachlor by transgenic rice plants expressing human CYP1A1, CYP2B6, and CYP2C19.

    PubMed

    Kawahigashi, Hiroyuki; Hirose, Sakiko; Ohkawa, Hideo; Ohkawa, Yasunobu

    2006-04-19

    This study evaluated the expression of human cytochrome P450 genes CYP1A1, CYP2B6, and CYP2C19 in rice plants (Oryza sativa cv. Nipponbare) introduced using the plasmid pIKBACH. The transgenic rice plants (pIKBACH rice plants) became more tolerant toward various herbicides than nontransgenic Nipponbare rice plants. Rice plants expressing pIKBACH grown in soil showed tolerance to the herbicides atrazine, metolachlor, and norflurazon and to a mixture of the three herbicides. The degradation of atrazine and metolachlor by pIKBACH rice plants was evaluated to confirm the metabolic activity of the introduced P450s. Although both pIKBACH and nontransgenic Nipponbare rice plants could decrease the amounts of the herbicides in plant tissue and culture medium, pIKBACH rice plants removed greater amounts in greenhouse experiments. The ability of pIKBACH rice plants to remove atrazine and metolachlor from soil was confirmed in large-scale experiments. The metabolism of herbicides by pIKBACH rice plants was enhanced by the introduced P450 species. Assuming that public and commercial acceptance is forthcoming, pIKBACH rice plants may become useful tools for the breeding of herbicide-tolerant crops and for phytoremediation of environmental pollution by organic chemicals. PMID:16608219

  18. Exploring Japan through Rice.

    ERIC Educational Resources Information Center

    Wojtan, Linda S.

    1998-01-01

    Explores the role of rice in Japanese culture by presenting historical background and teaching activities in a variety of categories, such as language, sociology, history, and contemporary politics. Suggests teachers create cross-cultural comparisons; for example, the role of corn in the United States. Provides a list of teacher resources. (CMK)

  19. Rice: chemistry and technology.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice has taken center stage this last decade, not only as an important provider of nourishment for the world’s population, but as a grain now recognized as having many unique nutritional and functional attributes with potential to be captured in a multitude of value-added food and non-food applicati...

  20. 7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice. (See also Â... Milled Rice Principles Governing Application of Standards § 868.310 Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled...

  1. 7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice. (See also Â... Milled Rice Principles Governing Application of Standards § 868.310 Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled...

  2. 7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice. (See also Â... classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice... (percent) Removed by a 5 plate 3 (percent) Removed by a 6 plate 3 (percent) Through a 6 sieve 3...

  3. Role of probiotic Lactobacillus fermentum KKL1 in the preparation of a rice based fermented beverage.

    PubMed

    Ghosh, Kuntal; Ray, Mousumi; Adak, Atanu; Halder, Suman K; Das, Arpan; Jana, Arijit; Parua Mondal, Saswati; Vágvölgyi, Csaba; Das Mohapatra, Pradeep K; Pati, Bikas R; Mondal, Keshab C

    2015-01-01

    A dominant lactic acid bacteria, Lactobacillus fermentum KKL1 was isolated from an Indian rice based fermented beverage and its fermentative behavior on rice was evaluated. The isolate grown well in rice and decreased the pH, with an increase of total titratable acidity on account of high yield in lactic acid and acetic acid. The production of α-amylase and glucoamylase by the strain reached plateau on 1st and 2nd day of fermentation respectively. The accumulation of malto-oligosaccharides of different degrees of polymerization was also found highest on 4th day. Besides, phytase activity along with accumulation of free minerals also unremittingly increased throughout the fermentation. The fermented materials showed free radical scavenging activity against DPPH radicals. In-vitro characteristics revealed the suitability of the isolate as probiotic organism. The above profiling revealed that probiotic L. fermentum KKL1 have the significant impact in preparation of rice beer and improves its functional characteristics. PMID:25693452

  4. Rice Glycosyltransferase (GT) Phylogenomic Database

    DOE Data Explorer

    Ronald, Pamela

    The Ronald Laboratory staff at the University of California-Davis has a primary research focus on the genes of the rice plant. They study the role that genetics plays in the way rice plants respond to their environment. They created the Rice GT Database in order to integrate functional genomic information for putative rice Glycosyltransferases (GTs). This database contains information on nearly 800 putative rice GTs (gene models) identified by sequence similarity searches based on the Carbohydrate Active enZymes (CAZy) database. The Rice GT Database provides a platform to display user-selected functional genomic data on a phylogenetic tree. This includes sequence information, mutant line information, expression data, etc. An interactive chromosomal map shows the position of all rice GTs, and links to rice annotation databases are included. The format is intended to "facilitate the comparison of closely related GTs within different families, as well as perform global comparisons between sets of related families." [From http://ricephylogenomics.ucdavis.edu/cellwalls/gt/genInfo.shtml] See also the primary paper discussing this work: Peijian Cao, Laura E. Bartley, Ki-Hong Jung and Pamela C. Ronalda. Construction of a Rice Glycosyltransferase Phylogenomic Database and Identification of Rice-Diverged Glycosyltransferases. Molecular Plant, 2008, 1(5): 858-877.

  5. In vitro adsorption revealing an apparent strong interaction between endophyte Pantoea agglomerans YS19 and host rice.

    PubMed

    Miao, Yuxuan; Zhou, Jia; Chen, Cuicui; Shen, Delong; Song, Wei; Feng, Yongjun

    2008-12-01

    Pantoea (formerly Enterobacter) agglomerans YS19 is a dominant diazotrophic endophyte isolated from rice (Oryza sativa cv. Yuefu) grown in a temperate-climate region in west Beijing, China. In vitro adsorption and invasion of YS19 on host plant root were studied in this research. Adsorption of YS19 on rice seedling roots closely resembled the Langmuir adsorption and showed a higher adsorption quantity than the control strains Paenibacillus polymyxa WY110 (a rhizospheric bacterium from the same rice cultivar) and Escherichia coli HB101 (a general model bacterium). Adsorption dynamics study revealed high rates and a long duration of the YS19-rice root adsorption process. Adsorption of YS19 was mainly observed on the root hair, though which it enters the plant. This in vitro adsorption study revealed an apparent strong interaction between YS19 and rice at the early endophyte-host recognition stage. PMID:18781359

  6. Rice LTG1 is involved in adaptive growth and fitness under low ambient temperature.

    PubMed

    Lu, Guangwen; Wu, Fu-Qing; Wu, Weixun; Wang, Hong-Jun; Zheng, Xiao-Ming; Zhang, Yunhui; Chen, Xiuling; Zhou, Kunneng; Jin, Mingna; Cheng, Zhijun; Li, Xueyong; Jiang, Ling; Wang, Haiyang; Wan, Jianmin

    2014-05-01

    Low temperature (LT) is one of the most prevalent factors limiting the productivity and geographical distribution of rice (Oryza sativa L.). Although significant progress has been made in elucidating the effect of LT on seed germination and reproductive development in rice, the genetic component affecting vegetative growth under LT remains poorly understood. Here, we report that rice cultivars harboring the dominant LTG1 (Low Temperature Growth 1) allele are more tolerant to LT (15-25°C, a temperature range prevalent in high-altitude, temperate zones and high-latitude areas), than those with the ltg1 allele. Using a map-based cloning strategy, we show that LTG1 encodes a casein kinase I. A functional nucleotide polymorphism was identified in the coding region of LTG1, causing a single amino acid substitution (I357K) that is associated with the growth rate, heading date and yield of rice plants grown at LT. We present evidence that LTG1 affects rice growth at LT via an auxin-dependent process(es). Furthermore, phylogenetic analysis of this locus suggests that the ltg1 haplotype arose before the domestication of rice in tropical climates. Together, our data demonstrate that LTG1 plays an important role in the adaptive growth and fitness of rice cultivars under conditions of low ambient temperature. PMID:24635058

  7. "Tinni" rice (Oryza rufipogon Griff.) production: an integrated sociocultural agroecosystem in eastern Uttar Pradesh of India.

    PubMed

    Singh, Ranjay K; Turner, Nancy J; Pandey, C B

    2012-01-01

    This study reports how Traditional Ecological Knowledge (TEK) and informal cultural institutions have conserved key varieties of the wildgrowing rice, 'tinni' (red rice, or brownbeard rice, Oriza rufipogon Griff.), within the Bhar community of eastern Uttar Pradesh, India. The study was conducted, using conventional and participatory methods, in 10 purposively selected Bhar villages. Two distinct varieties of tinni ('tinni patali' and 'tinni moti') with differing habitats and phenotypic characters were identified. Seven microecosystems (Kari, Badaila, Chammo, Karmol, Bhainsiki, Bhainsala and Khodailia) were found to support these varieties in differing proportions. Tinni rice can withstand more extreme weather conditions (the highest as well as lowest temperatures and rainfall regimes) than the 'genetically improved' varieties of rice (Oriza sativa L.) grown in the region. Both tinni varieties are important bioresources for the Bhar's subsistence livelihoods, and they use distinctive conservation approaches in their maintenance. Bhar women are the main custodians of tinni rice agrobiodiversity, conserving tinni through an institution called Sajha. Democratic decision-making at meetings organized by village elders determines the market price of the tinni varieties. Overall, the indigenous institutions and women's participation seem to have provided safeguards from excessive exploitation of tinni rice varieties. The maintenance of tinni through cultural knowledge and institutions serves as an example of the importance of locally maintained crop varieties in contributing to people's resilience and food security in times of rapid social and environmental change. PMID:21959872

  8. Tyramine accumulation in rice cells caused a dwarf phenotype via reduced cell division.

    PubMed

    Kim, Young Soon; Park, Sangkyu; Kang, Kiyoon; Lee, Kyungjin; Back, Kyoungwhan

    2011-02-01

    Transgenic rice plants overexpressing a rice tyrosine decarboxylase (TyDC) exhibited a dwarf phenotype with a high level of tyramine accumulation. The height of transgenic rice was reduced on average to 35% of the wild-type height, whereas the number of tillers increased to 190% that of wild type. When judged by cellular distribution of tyramine and tyramine derivatives, the level of tyramine in soluble and insoluble fractions was higher than that of tyramine derivatives such as 4-coumaroyltyramine (CT) in the transgenic rice plants, suggesting that tyramine rather than its derivatives was a causative compound triggering the dwarf phenotype. Microscopic observation revealed that cell size in the transgenic lines was maintained, with a slightly irregular arrangement in the leaf mesophyll cells. When wild-type rice seeds were grown in the presence of tyramine, rice seedlings also showed stunted phenotypes in a dose-dependent manner. When these stunted seedlings were employed to measure the degree of cellular proliferation by bromodeoxyuridine incorporation, only small numbers of cells were found to retain labeled nuclei in shoot tips compared with the untreated control. These results show that the dwarf phenotype associated with tyramine accumulation in transgenic rice plants is attributable to a reduction in cell number rather than cell size. In addition, our dwarf phenotype caused by tyramine was not closely associated with known dwarf genes such as D88. PMID:20978800

  9. Ameliorants to immobilize Cd in rice paddy soils contaminated by abandoned metal mines in Korea.

    PubMed

    Ok, Yong Sik; Kim, Sung-Chul; Kim, Dong-Kuk; Skousen, Jeffrey G; Lee, Jin-Soo; Cheong, Young-Wook; Kim, Su-Jung; Yang, Jae E

    2011-01-01

    The cadmium (Cd) content of rice grain grown in metal-contaminated paddy soils near abandoned metal mines in South Korea was found to exceed safety guidelines (0.2 mg Cd kg⁻¹) set by the Korea Food and Drug Administration (KFDA). However, current remediation technologies for heavy metal-contaminated soils have limited application with respect to rice paddy soils. Laboratory and greenhouse experiments were conducted to assess the effects of amending contaminated rice paddy soils with zerovalent iron (ZVI), lime, humus, compost, and combinations of these compounds to immobilize Cd and inhibit Cd translocation to rice grain. Sequential extraction analysis revealed that treatment with the ameliorants induced a 50-90% decrease in the bioavailable Cd fractions when compared to the untreated control soil. When compared to the control, Cd uptake by rice was decreased in response to treatment with ZVI + humus (69%), lime (65%), ZVI + compost (61%), compost (46%), ZVI (42%), and humus (14%). In addition, ameliorants did not influence rice yield when compared to that of the control. Overall, the results of this study indicated that remediation technologies using ameliorants effectively reduce Cd bioavailability and uptake in contaminated rice paddy soils. PMID:21052787

  10. The Impact of Climate on the Spread of Rice to North-Eastern China: A New Look at the Data from Shandong Province

    PubMed Central

    d’Alpoim Guedes, Jade; Jin, Guiyun; Bocinsky, R. Kyle

    2015-01-01

    Moving crops outside of their original centers of domestication was sometimes a challenging process. Because of its substantial heat requirements, moving rice agriculture outside of its homelands of domestication was not an easy process for farmers in the past. Using crop niche models, we examine the constraints faced by ancient farmers and foragers as they moved rice to its most northerly extent in Ancient China: Shandong province. Contrary to previous arguments, we find that during the climatic optimum rice could have been grown in the region. Climatic cooling following this date had a clear impact on the distribution of rice, one that may have placed adaptive pressure on rice to develop a temperate phenotype. Following the development of this temperate phenotype, rice agriculture could once again become implanted in select areas of north-eastern China. PMID:26125619

  11. Potential production simulation and optimal nutrient management of two hybrid rice varieties in Jinhua, Zhejiang Province, China.

    PubMed

    Xie, Wen-xia; Wang, Guang-huo; Zhang, Qi-chun

    2007-07-01

    Potential growth of two widely-grown hybrid rice varieties in the Jinhua district of Zhejiang Province, Shanyou63 for mid-rice and Xieyou46 for late rice, was simulated using a crop growth model of WOFOST. Parameters of the rice growth in WOFOST were calibrated through field experiments from 1999 to 2002 in Jinhua. The potential yield simulated with WOFOST was about 12 t/ha for Shanyou63 and 10 t/ha for Xieyou46, which are in good agreement with the highest recorded yield obtained in this area. Under farmers practice, current yield is about 7.5 t/ha for Shanyou63 and 6.5 t/ha for Xieyou46. There is a gap between the actual rice yield and the potential yield for these two hybrid rice varieties grown in this area. The attainable target yields were set to 70% to 75% of their potential yields for the two varieties. A recently developed software "Nutrient Decision Support System (NuDSS)" for irrigated rice was used to optimize nutrient management for these two rice varieties. According to NuDSS, the optimal fertilizer N requirement for the target yields was about 150 kg/ha for Shanyou63 and about 120 kg/ha for Xieyou46, which were only about 70% of the fertilizer N application under current farmers' practice. Comparing with farmers' practice, there is great potential to increase actual rice yields and to reduce fertilizer N use rates by improving rice crop management practice in Jinhua. PMID:17610328

  12. Potential production simulation and optimal nutrient management of two hybrid rice varieties in Jinhua, Zhejiang Province, China*

    PubMed Central

    Xie, Wen-xia; Wang, Guang-huo; Zhang, Qi-chun

    2007-01-01

    Potential growth of two widely-grown hybrid rice varieties in the Jinhua district of Zhejiang Province, Shanyou63 for mid-rice and Xieyou46 for late rice, was simulated using a crop growth model of WOFOST. Parameters of the rice growth in WOFOST were calibrated through field experiments from 1999 to 2002 in Jinhua. The potential yield simulated with WOFOST was about 12 t/ha for Shanyou63 and 10 t/ha for Xieyou46, which are in good agreement with the highest recorded yield obtained in this area. Under farmers practice, current yield is about 7.5 t/ha for Shanyou63 and 6.5 t/ha for Xieyou46. There is a gap between the actual rice yield and the potential yield for these two hybrid rice varieties grown in this area. The attainable target yields were set to 70% to 75% of their potential yields for the two varieties. A recently developed software “Nutrient Decision Support System (NuDSS)” for irrigated rice was used to optimize nutrient management for these two rice varieties. According to NuDSS, the optimal fertilizer N requirement for the target yields was about 150 kg/ha for Shanyou63 and about 120 kg/ha for Xieyou46, which were only about 70% of the fertilizer N application under current farmers’ practice. Comparing with farmers’ practice, there is great potential to increase actual rice yields and to reduce fertilizer N use rates by improving rice crop management practice in Jinhua. PMID:17610328

  13. Genetic diversity for mycorrhizal symbiosis and phosphate transporters in rice.

    PubMed

    Jeong, Kwanho; Mattes, Nicolas; Catausan, Sheryl; Chin, Joong Hyoun; Paszkowski, Uta; Heuer, Sigrid

    2015-11-01

    Phosphorus (P) is a major plant nutrient and developing crops with higher P-use efficiency is an important breeding goal. In this context we have conducted a comparative study of irrigated and rainfed rice varieties to assess genotypic differences in colonization with arbuscular mycorrhizal (AM) fungi and expression of different P transporter genes. Plants were grown in three different soil samples from a rice farm in the Philippines. The data show that AM symbiosis in all varieties was established after 4 weeks of growth under aerobic conditions and that, in soil derived from a rice paddy, natural AM populations recovered within 6 weeks. The analysis of AM marker genes (AM1, AM3, AM14) and P transporter genes for the direct Pi uptake (PT2, PT6) and AM-mediated pathway (PT11, PT13) were largely in agreement with the observed root AM colonization providing a useful tool for diversity studies. Interestingly, delayed AM colonization was observed in the aus-type rice varieties which might be due to their different root structure and might confer an advantage for weed competition in the field. The data further showed that P-starvation induced root growth and expression of the high-affinity P transporter PT6 was highest in the irrigated variety IR66 which also maintained grain yield under P-deficient field conditions. PMID:26466747

  14. Anticlastogenicity and Anticarcinogenicity of Purple Rice Extract in Rats.

    PubMed

    Punvittayagul, Charatda; Sankam, Paweena; Taya, Sirinya; Wongpoomchai, Rawiwan

    2016-01-01

    Oryza sativa L. var. indica cv. Kum Doi Saket is a pigmented rice variety grown in northern Thailand. Our previous study found that the methanol extract of purple rice seed had the highest level of antimutagenicity in a Salmonella mutation assay. The present study was designed to evaluate its in vivo anticlastogenic and anticarcinogenic potentials. The purple rice extract had no acute toxicity on rats. The oral administration of 1,000 mg/kg body weight (bw) of the extract for 28 days did not increase the number of micronucleated hepatocytes. Interestingly, it significantly reduced the amount of micronucleus formation in the liver of diethylnitrosamine (DEN)-treated rats. The inhibitory mechanism involved the induction of hepatic glutathione S-transferase (GST) activity. In addition, oral administration of 500 mg/kg bw extract for 10 weeks significantly decreased the number of hepatic GST placental form positive foci, but did not modulate the number of colonic aberrant crypt foci in DEN- and dimethylhydrazine-initiated rats. In conclusion, the methanol extract of purple rice seed showed no toxicity, clastogenicity, or carcinogenicity in laboratory rats. It did display chemopreventive activity against the early stages of rat hepatocarcinogenesis. PMID:27115481

  15. Rice: The First Crop Genome.

    PubMed

    Jackson, Scott A

    2016-12-01

    Rice was the first sequenced crop genome, paving the way for the sequencing of additional and more complicated crop genomes. The impact that the genome sequence made on rice genetics and breeding research was immediate, as evidence by citations and DNA marker use. The impact on other crop genomes was evident too, particularly for those within the grass family. As we celebrate 10 years since the completion of the rice genome sequence, we look forward to new empowering tool sets that will further revolutionize research in rice genetics and breeding and result in varieties that will continue to feed a growing population. PMID:27003180

  16. Studies on nutrient uptake of rice and characteristics of soil microorganisms in a long-term fertilization experiments for irrigated rice.

    PubMed

    Zhang, Qi-chun; Wang, Guang-huo

    2005-02-01

    The ecosystem characteristics of soil microorganism and the nutrient uptake of irrigated rice were investigated in a split-block experiment with different fertilization treatments, including control (no fertilizer application), PK, NK, NP, NPK fertilization, in the main block, and conventional rice and hybrid rice comparison, in the sub block. Average data of five treatments in five years indicated that the indigenous N supply (INS) capacity ranged from 32.72 to 93.21 kg/ha; that indigenous P supply (IPS) capacity ranged from 7.42 to 32.25 kg/ha; and that indigenous K supply (IKS) capacity ranged from 16.24 to 140.51 kg/ha, which showed that soil available nutrient pool depletion might occur very fast and that P, K deficiency has become a constraint to increasing yields of consecutive crops grown without fertilizer application. It was found that soil nutrient deficiency and unbalanced fertilization to rice crop had negative effect on the diversity of the microbial community and total microbial biomass in the soil. The long-term fertilizer experiment (LTFE) also showed that balanced application of N, P and K promoted microbial biomass growth and improvement of community composition. Unbalanced fertilization reduced microbial N and increased C/N ratio of the microbial biomass. Compared with inbred rice, hybrid rice behavior is characterized by physiological advantage in nutrient uptake and lower internal K use efficiency. PMID:15633252

  17. Amended final report on the safety assessment of Oryza Sativa (rice) Bran Oil, Oryza Sativa (rice) Germ Oil, Rice Bran Acid,Oryza Sativa (rice) Bran Wax, Hydrogenated Rice Bran Wax, Oryza Sativa (rice)Bran Extract, Oryza Sativa (rice) Extract, Oryza Sativa (rice) Germ Powder, Oryza Sativa (rice) Starch, Oryza Sativa (rice) Bran, Hydrolyzed Rice Bran Extract, Hydrolyzed Rice Bran Protein, Hydrolyzed Rice Extract, and Hydrolyzed Rice Protein.

    PubMed

    2006-01-01

    This report addresses the safety of cosmetic ingredients derived from rice, Oryza sativa. Oils, Fatty Acids, and Waxes: Rice Bran Oil functions in cosmetics as a conditioning agent--occlusive in 39 formulations across a wide range of product types. Rice Germ Oil is a skin-conditioning agent--occlusive in six formulations in only four product categories. Rice Bran Acid is described as a surfactant-cleansing agent, but was not in current use. Rice Bran Wax is a skin-conditioning agent--occlusive in eight formulations in five product categories. Industry did not directly report any use of Rice Bran Wax. Hydrogenated Rice Bran Wax is a binder, skin-conditioning agent--occlusive, and viscosity-increasing agent--nonaqueous in 11 formulations in six product categories. Rice Bran Oil had an oral LD50 of > 5 g/kg in white rats and Rice Wax had an oral LD50 of > 24 g/kg in male mice. A three-generation oral dosing study reported no toxic or teratologic effects in albino rats fed 10% Rice Bran Oil compared to a control group fed Peanut Oil. Undiluted Rice Bran Oil, Rice Germ Oil, and Hydrogenated Rice Bran Wax were not irritants in animal skin tests. Rice Bran Oil was not a sensitizer. Rice Bran Oil, Rice Germ Oil, Rice Wax, and Hydrogenated Rice Bran Wax were negative in ocular toxicity assays. A mixture of Rice Bran Oil and Rice Germ Oil had a ultraviolet (UV) absorption maximum at 315 nm, but was not phototoxic in a dermal exposure assay. Rice Bran Oil was negative in an Ames assay, and a component, gamma-oryzanol, was negative in bacterial and mammalian mutagenicity assays. Rice oils, fatty acids, and waxes were, at most, mildly irritating in clinical studies. Extracts: Rice Bran Extract is used in six formulations in four product categories. Rice Extract is a hair-conditioning agent, but was not in current use. Hydrolyzed Rice Extract is used in four formulations and current concentration of use data were provided for other uses. Hydrolyzed Rice Bran Extract, described

  18. Root hair formation in rice (Oryza sativa L.) differs between root types and is altered in artificial growth conditions.

    PubMed

    Nestler, Josefine; Keyes, Samuel David; Wissuwa, Matthias

    2016-06-01

    Root hairs are important sites for nutrient uptake, especially in P limiting conditions. Here we provide first insights into root hair development for the diverse root types of rice grown under different conditions, and show the first in situ images of rice root hairs in intact soil. Roots of plants grown in upland fields produced short root hairs that showed little responsiveness to P deficiency, and had a higher root hair density in the high P condition. These results were reproducible in rhizoboxes under greenhouse conditions. Synchrotron-based in situ analysis of root hairs in intact soil further confirmed this pattern of root hair formation. In contrast, plants grown in nutrient solution produced more and longer root hairs in low P conditions, but these were unequally distributed among the different root types. While nutrient solution-grown main roots had longer hairs compared to upland field-grown main roots, second order lateral roots did not form any root hairs in nutrient solution-grown plants. Furthermore, root hair formation for plants grown in flooded lowland fields revealed few similarities with those grown in nutrient solution, thus defining nutrient solution as a possible measure of maximal, but not natural root hair development. By combining root hair length and density as a measure for root hair impact on the whole soil-grown root system we show that lateral roots provided the majority of root hair surface. PMID:26976815

  19. Inspections of radiocesium concentration levels in rice from Fukushima Prefecture after the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Nihei, Naoto; Tanoi, Keitaro; Nakanishi, Tomoko M

    2015-01-01

    We summarize the inspections of radiocesium concentration levels in rice produced in Fukushima Prefecture, Japan, for 3 years from the nuclear accident in 2011. In 2011, three types of verifications, preliminary survey, main inspection, and emergency survey, revealed that rice with radiocesium concentration levels over 500 Bq/kg (the provisional regulation level until March 2012 in Japan) was identified in the areas north and west of the Fukushima nuclear power plant. The internal exposure of an average adult eating rice grown in the area north of the nuclear plant was estimated as 0.05 mSv/year. In 2012, Fukushima Prefecture authorities decided to investigate the radiocesium concentration levels in all rice using custom-made belt conveyor testers. Notably, rice with radiocesium concentration levels over 100 Bq/kg (the new standard since April 2012 in Japan) were detected in only 71 and 28 bags out of the total 10,338,000 in 2012 and 11,001,000 in 2013, respectively. We considered that there were almost no rice exceeding 100 Bq/kg produced in Fukushima Prefecture after 3 years from the nuclear accident, and the safety of Fukushima's rice were ensured because of the investigation of all rice. PMID:25731663

  20. Inspections of radiocesium concentration levels in rice from Fukushima Prefecture after the Fukushima Dai-ichi Nuclear Power Plant accident

    NASA Astrophysics Data System (ADS)

    Nihei, Naoto; Tanoi, Keitaro; Nakanishi, Tomoko M.

    2015-03-01

    We summarize the inspections of radiocesium concentration levels in rice produced in Fukushima Prefecture, Japan, for 3 years from the nuclear accident in 2011. In 2011, three types of verifications, preliminary survey, main inspection, and emergency survey, revealed that rice with radiocesium concentration levels over 500 Bq/kg (the provisional regulation level until March 2012 in Japan) was identified in the areas north and west of the Fukushima nuclear power plant. The internal exposure of an average adult eating rice grown in the area north of the nuclear plant was estimated as 0.05 mSv/year. In 2012, Fukushima Prefecture authorities decided to investigate the radiocesium concentration levels in all rice using custom-made belt conveyor testers. Notably, rice with radiocesium concentration levels over 100 Bq/kg (the new standard since April 2012 in Japan) were detected in only 71 and 28 bags out of the total 10,338,000 in 2012 and 11,001,000 in 2013, respectively. We considered that there were almost no rice exceeding 100 Bq/kg produced in Fukushima Prefecture after 3 years from the nuclear accident, and the safety of Fukushima's rice were ensured because of the investigation of all rice.

  1. Inspections of radiocesium concentration levels in rice from Fukushima Prefecture after the Fukushima Dai-ichi Nuclear Power Plant accident

    PubMed Central

    Nihei, Naoto; Tanoi, Keitaro; Nakanishi, Tomoko M.

    2015-01-01

    We summarize the inspections of radiocesium concentration levels in rice produced in Fukushima Prefecture, Japan, for 3 years from the nuclear accident in 2011. In 2011, three types of verifications, preliminary survey, main inspection, and emergency survey, revealed that rice with radiocesium concentration levels over 500 Bq/kg (the provisional regulation level until March 2012 in Japan) was identified in the areas north and west of the Fukushima nuclear power plant. The internal exposure of an average adult eating rice grown in the area north of the nuclear plant was estimated as 0.05 mSv/year. In 2012, Fukushima Prefecture authorities decided to investigate the radiocesium concentration levels in all rice using custom-made belt conveyor testers. Notably, rice with radiocesium concentration levels over 100 Bq/kg (the new standard since April 2012 in Japan) were detected in only 71 and 28 bags out of the total 10,338,000 in 2012 and 11,001,000 in 2013, respectively. We considered that there were almost no rice exceeding 100 Bq/kg produced in Fukushima Prefecture after 3 years from the nuclear accident, and the safety of Fukushima's rice were ensured because of the investigation of all rice. PMID:25731663

  2. Outcrossing Potential between U.S. Blackhull Red Rice and Indica Rice Cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weedy red rice is a major weed pest of rice in the southern U.S. Outcrossing between red rice and commercial tropical japonica rice cultivars has resulted in new weed biotypes that further hinder the effectiveness of weed management. In recent years, indica rice has been used increasingly as a ger...

  3. Maximum outcrossing rate and genetic compatibility between red rice (Oryza sativa) biotypes and Clearfield™ rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although red rice can be selectively controlled with imazethapyr in ClearfieldTM (CL) rice, the transfer of the imazethapyr-resistant gene from CL rice to red rice is an ecological risk. Previous experiments indicated that flowering synchronization and genetic compatibility between cultivated rice a...

  4. Differences Between Rice and Wheat in Temperature Responses of Photosynthesis and Plant Growth

    PubMed Central

    Nagai, Takeshi; Makino, Amane

    2009-01-01

    The temperature responses of photosynthesis (A) and growth were examined in rice and wheat grown hydroponically under day/night temperature regimes of 13/10, 19/16, 25/19, 30/24 and 37/31°C. Irrespective of growth temperature, the maximal rates of A were found to be at 30–35°C in rice and at 25–30°C in wheat. Below 25°C the rates were higher in wheat, while above 30°C they were higher in rice. However, in both species, A measured at the growth temperature remained almost constant irrespective of temperature. Biomass production and relative growth rate (RGR) were greatest in rice grown at 30/24°C and in wheat grown at 25/19°C. Although there was no difference between the species in the optimal temperature of the leaf area ratios (LARs), the net assimilation rate (NAR) in rice decreased at low temperature (19/16°C) while the NAR in wheat decreased at high temperature (37/31°C). For both species, the N-use efficiency (NUE) for growth rate (GR), estimated by dividing the NAR by leaf-N content, correlated with GR and with biomass production. Similarly, when NUE for A at growth temperature was estimated, the temperature response of NUE for A was similar to that of NUE for GR in both species. The results suggest that the difference between rice and wheat in the temperature response of biomass production depends on the difference in temperature dependence of NUE for A. PMID:19251744

  5. Update on organic rice research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic products command a premium in the marketplace and bring greater farmgate value to growers and processors. Although total rice acreage has decreased in Texas over the last ten years, there has been an increase in rice acreage produced under organic management. USDA ARS has conducted research ...

  6. 75 FR 56911 - Request for Public Comment on the United States Standards for Rough Rice, Brown Rice for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ..., Brown Rice for Processing, and Milled Rice standards were last revised in 1993 (58 FR 68015) and appear... technology used to harvest, process, and test rice; and also rice marketing. To ensure that standards and... learn more about Rough Rice, Brown Rice for Processing, and Milled Rice standardization and...

  7. Effect of coated urea on cadmium accumulation in Oryza sativa L. grown in contaminated soil.

    PubMed

    Xu, Chao; Wu, Zisong; Zhu, Qihong; Zhu, Hanhua; Zhang, Yangzhu; Huang, Daoyou

    2015-11-01

    Experiments were conducted to determine the effects of three types of coated urea on the accumulation of cadmium (Cd) in rice (Oryza sativa L.) grown in contaminated soil. Pot-culture experiments were conducted in a greenhouse from July to November 2012 on the rice cultivar "Hua Hang Si Miao" in Guangzhou (China). The experimental design was completely randomized with four treatments and three replications. The treatments were control (CK) (N 0 mg/kg), prilled urea (PU) (N 200 mg/kg), polymer-coated urea (PCU) (N 200 mg/kg), and sulfur-coated urea (SCU) (N 200 mg/kg). Our results indicated that applications of PCU and SCU slightly increased the dry weight of rice grains. The application of SCU significantly decreased the CaCl2 and toxicity characteristic leaching procedure (TCLP)-extractable Cd concentrations by 15.4 and 56.1%, respectively. Sequential extractions showed that PCU and SCU applications led to a significant decrease in Cd in the exchangeable fraction and an increase in the bound iron (Fe) and manganese (Mn) oxides fractions. Cd concentrations in grains treated with PCU were reduced by 11.7%, whereas SCU significantly reduced Cd concentrations by 29.1%. SCU reduced Cd transfer from the straws to the grain. Our results demonstrated that PCU and SCU may be effective in mitigating Cd accumulation in rice grown in acidic Cd-contaminated soil, especially in plants receiving SCU. PMID:26514799

  8. Evidence for divergence of response in Indica, Japonica, and wild rice to high CO2 × temperature interaction.

    PubMed

    Wang, Diane R; Bunce, James A; Tomecek, Martha B; Gealy, David; McClung, Anna; McCouch, Susan R; Ziska, Lewis H

    2016-07-01

    High CO2 and high temperature have an antagonistic interaction effect on rice yield potential and present a unique challenge to adapting rice to projected future climates. Understanding how the differences in response to these two abiotic variables are partitioned across rice germplasm accessions may be key to identifying potentially useful sources of resilient alleles for adapting rice to climate change. In this study, we evaluated eleven globally diverse rice accessions under controlled conditions at two carbon dioxide concentrations (400 and 600 ppm) and four temperature environments (29 °C day/21 °C night; 29 °C day/21 °C night with additional heat stress at anthesis; 34 °C day/26 °C night; and 34 °C day/26 °C night with additional heat stress at anthesis) for a suite of traits including five yield components, five growth characteristics, one phenological trait, and four photosynthesis-related measurements. Multivariate analyses of mean trait data from these eight treatments divide our rice panel into two primary groups consistent with the genetic classification of INDICA/INDICA-like and JAPONICA populations. Overall, we find that the productivity of plants grown under elevated [CO2 ] was more sensitive (negative response) to high temperature stress compared with that of plants grown under ambient [CO2 ] across this diversity panel. We report differential response to CO2 × temperature interaction for INDICA/INDICA-like and JAPONICA rice accessions and find preliminary evidence for the beneficial introduction of exotic alleles into cultivated rice genomic background. Overall, these results support the idea of using wild or currently unadapted gene pools in rice to enhance breeding efforts to secure future climate change adaptation. PMID:26959982

  9. Investigating the Contribution of the Phosphate Transport Pathway to Arsenic Accumulation in Rice1[W

    PubMed Central

    Wu, Zhongchang; Ren, Hongyan; McGrath, Steve P.; Wu, Ping; Zhao, Fang-Jie

    2011-01-01

    Arsenic (As) accumulation in rice (Oryza sativa) may pose a significant health risk to consumers. Plants take up different As species using various pathways. Here, we investigated the contribution of the phosphate (Pi) transport pathway to As accumulation in rice grown hydroponically or under flooded soil conditions. In hydroponic experiments, a rice mutant defective in OsPHF1 (for phosphate transporter traffic facilitator1) lost much of the ability to take up Pi and arsenate and to transport them from roots to shoots, whereas transgenic rice overexpressing either the Pi transporter OsPht1;8 (OsPT8) or the transcription factor OsPHR2 (for phosphate starvation response2) had enhanced abilities of Pi and arsenate uptake and translocation. OsPT8 was found to have a high affinity for both Pi and arsenate, and its overexpression increased the maximum influx by 3- to 5-fold. In arsenate-treated plants, both arsenate and arsenite were detected in the xylem sap, with the proportion of the latter increasing with the exposure time. Under the flooded soil conditions, the phf1 mutant took up less Pi whereas the overexpression lines took up more Pi. But there were no similar effects on As accumulation and distribution. Rice grain contained predominantly dimethylarsinic acid and arsenite, with arsenate being a minor species. These results suggest that the Pi transport pathway contributed little to As uptake and transport to grain in rice plants grown in flooded soil. Transgenic approaches to enhance Pi acquisition from paddy soil through the overexpression of Pi transporters may not increase As accumulation in rice grain. PMID:21715673

  10. Investigating the contribution of the phosphate transport pathway to arsenic accumulation in rice.

    PubMed

    Wu, Zhongchang; Ren, Hongyan; McGrath, Steve P; Wu, Ping; Zhao, Fang-Jie

    2011-09-01

    Arsenic (As) accumulation in rice (Oryza sativa) may pose a significant health risk to consumers. Plants take up different As species using various pathways. Here, we investigated the contribution of the phosphate (Pi) transport pathway to As accumulation in rice grown hydroponically or under flooded soil conditions. In hydroponic experiments, a rice mutant defective in OsPHF1 (for phosphate transporter traffic facilitator1) lost much of the ability to take up Pi and arsenate and to transport them from roots to shoots, whereas transgenic rice overexpressing either the Pi transporter OsPht1;8 (OsPT8) or the transcription factor OsPHR2 (for phosphate starvation response2) had enhanced abilities of Pi and arsenate uptake and translocation. OsPT8 was found to have a high affinity for both Pi and arsenate, and its overexpression increased the maximum influx by 3- to 5-fold. In arsenate-treated plants, both arsenate and arsenite were detected in the xylem sap, with the proportion of the latter increasing with the exposure time. Under the flooded soil conditions, the phf1 mutant took up less Pi whereas the overexpression lines took up more Pi. But there were no similar effects on As accumulation and distribution. Rice grain contained predominantly dimethylarsinic acid and arsenite, with arsenate being a minor species. These results suggest that the Pi transport pathway contributed little to As uptake and transport to grain in rice plants grown in flooded soil. Transgenic approaches to enhance Pi acquisition from paddy soil through the overexpression of Pi transporters may not increase As accumulation in rice grain. PMID:21715673

  11. Arsenic bioavailability to rice is elevated in Bangladeshi paddy soils.

    PubMed

    Khan, K Asaduzzaman; Stroud, Jacqueline L; Zhu, Yong-Guan; McGrath, Steve P; Zhao, Fang-Jie

    2010-11-15

    Some paddy soils in the Bengal delta are contaminated with arsenic (As) due to irrigation of As-laden groundwater, which may lead to yield losses and elevated As transfer to the food chain. Whether these soils have a higher As bioavailability than other soils containing either geogenic As or contaminated by mining activities was investigated in a pot experiment. Fourteen soils varying in the source and the degree (4-138 mg As kg 1⁻¹) of As contamination were collected, 10 from Bangladeshi paddy fields (contaminated by irrigation water) and two each from China and the UK (geogenic or mining impacted), for comparison. Bangladeshi soils had higher percentages of the total As extractable by ammonium phosphate (specifically sorbed As) than other soils and also released more As into the porewater upon flooding. Porewater As concentrations increased with increasing soil As concentrations more steeply in Bangladeshi soils, with arsenite being the dominant As species. Rice growth and grain yield decreased markedly in Bangladeshi soils containing > 13 mg As kg 1⁻¹, but not in the other soils. Phosphate-extractable or porewater As was a better indicator of As bioavailability than total soil As. Rice straw As concentrations increased with increasing soil As concentrations; however, As phytotoxicity appeared to result in lower grain As concentrations. The relative proportions of inorganic As and dimethylarsinic acid (DMA) in grain varied among soils, and the percentage DMA was larger in greenhouse-grown plants than grain samples collected from the paddy fields of the same soil and the same rice cultivar, indicating a strong environmental influence on As species found in rice grain. This study shows that Bangladeshi paddy soils contaminated by irrigation had a higher As bioavailability than other soils, resulting in As phytotoxicity in rice and substantial yield losses. PMID:20977268

  12. Effect of elevated CO2 on degradation of azoxystrobin and soil microbial activity in rice soil.

    PubMed

    Manna, Suman; Singh, Neera; Singh, V P

    2013-04-01

    An experiment was conducted in open-top chambers (OTC) to study the effect of elevated CO2 (580 ± 20 μmol mol(-1)) on azoxystrobin degradation and soil microbial activities. Results indicated that elevated CO2 did not have any significant effect on the persistence of azoxystrobin in rice-planted soil. The half-life values for the azoxystrobin in rice soils were 20.3 days in control (rice grown at ambient CO2 outdoors), 19.3 days in rice grown under ambient CO2 atmosphere in OTC, and 17.5 days in rice grown under elevated CO2 atmosphere in OTC. Azoxystrobin acid was recovered as the only metabolite of azoxystrobin, but it did not accumulate in the soil/water and was further metabolized. Elevated CO2 enhanced soil microbial biomass (MBC) and alkaline phosphatase activity of soil. Compared with rice grown at ambient CO2 (both outdoors and in OTC), the soil MBC at elevated CO2 increased by twofold. Elevated CO2 did not affect dehydrogenase, fluorescein diacetate, and acid phosphatase activity. Azoxystrobin application to soils, both ambient and elevated CO2, inhibited alkaline phosphates activity, while no effect was observed on other enzymes. Slight increase (1.8-2 °C) in temperature inside OTC did not affect microbial parameters, as similar activities were recorded in rice grown outdoors and in OTC at ambient CO2. Higher MBC in soil at elevated CO2 could be attributed to increased carbon availability in the rhizosphere via plant metabolism and root secretion; however, it did not significantly increase azoxystrobin degradation, suggesting that pesticide degradation was not the result of soil MBC alone. Study suggested that increased CO2 levels following global warming might not adversely affect azoxystrobin degradation. However, global warming is a continuous and cumulative process, therefore, long-term studies are necessary to get more realistic assessment of global warming on fate of pesticide. PMID:22773147

  13. Hydrology and Species-Specific Effects of Bacopa monnieri and Leersia oryzoides on Soil and Water Chemistry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an eight week greenhouse experiment, Bacopa monnieri (Water Hyssop) and Leersia oryzoides (Rice Cutgrass) were compared for nutrient assimilation as well as soil and water chemistry under variable flooding regimes using a nutrient solution rich in nitrogen (N) and phosphorus (P). Soil redox poten...

  14. Gene flow from herbicide-resistant and non-resistant rice into red rice populations in U.S. rice fields: A survey of current evidence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diverse red rice types infest U.S. rice fields. These infestations have remained widespread despite recent successes in controlling red rice in newly-introduced herbicide-resistant rice systems. As a result, the distribution and genetic background of red rice, and the degree to which red rice inte...

  15. The flexible interrelation between AOX respiratory pathway and photosynthesis in rice leaves.

    PubMed

    Feng, Hanqing; Li, Hongyu; Li, Xin; Duan, Jiangong; Liang, Houguo; Zhi, Dejuan; Ma, Jun

    2007-01-01

    Alternative respiratory pathway was investigated in rice seedlings grown under total darkness, light/dark cycle, or continuous light. The capacity of the alternative pathway was relatively higher in leaves that had longer light exposure. An analysis of rice AOX1 multigene family revealed that AOX1c, but not AOX1a and AOX1b, had a light-independent expression. The alternative oxidase (AOX) inhibitor, salicylhydroxamic acid (SHAM, 1mM), inhibited nearly 68% of the capacity of the alternative pathway in leaves grown under different light conditions. The plants grown under different light periods were treated with SHAM and then were exposed to illumination for 4h. The transition from dark to 4h of light stimulated the capacity of alternative pathway in etiolated rice seedlings and in those grown under light/dark cycle, whereas the capacity of the alternative pathway was constant in seedlings grown under continuous light with additional 4h of illumination. Etiolated leaves did not show any CO(2) fixation after 4h of illumination, and the increase in chlorophyll content was delayed by the SHAM pretreatment. When seedlings grown under light/dark cycle were moved from dark and exposed to 4h of light, increases in chlorophyll content and CO(2) fixation rate were reduced by SHAM. Although these parameters were stable in plants grown under continuous light, SHAM decreased CO(2) fixation rate but not the chlorophyll content. These results indicate that the role and regulation of AOX in light are determined by the developmental stage of plant photosynthetic apparatus. PMID:17408956

  16. Screening for Abiotic Stress Tolerance in Rice: Salt, Cold, and Drought.

    PubMed

    Almeida, Diego M; Almadanim, M Cecília; Lourenço, Tiago; Abreu, Isabel A; Saibo, Nelson J M; Oliveira, M Margarida

    2016-01-01

    Rice (Oryza sativa) is the primary source of food for more than half of the world population. Most rice varieties are severely injured by abiotic stresses, with strong social and economic impact. Understanding rice responses to stress may help breeding for more tolerant varieties. However, papers dealing with stress experiments often describe very different experimental designs, thus making comparisons difficult. The use of identical setups is the only way to generate comparable data. This chapter is organized into three sections, describing the experimental conditions established at the Genomics of Plant Stress (GPlantS) unit of ITQB to assess the response of rice plants to three different abiotic stresses--high salinity, cold stress, and drought. All sections include a detailed description of the materials and methodology, as well as useful notes gathered from the GPlantS team's experience. We use rice seedlings as plants at this stage show high sensitivity to abiotic stresses. For the salt and cold stress assays we use hydroponic cultures, while for the drought assay plants are grown in soil and subjected to water withholding. All setups enable visual score determination and are suitable for sample collection along the imposition of stress. The proposed methodologies are simple and affordable to implement in most labs, allowing the discrimination of several rice genotypes at the molecular and phenotypic level. PMID:26867623

  17. High vapor pressure deficit drives salt-stress-induced rice yield losses in India.

    PubMed

    Tack, Jesse; Singh, Rakesh K; Nalley, Lawton L; Viraktamath, Basavaraj C; Krishnamurthy, Saraswathipura L; Lyman, Nate; Jagadish, Krishna S V

    2015-04-01

    Flooded rice is grown across wide geographic boundaries from as far north as Manchuria and as far south as Uruguay and New South Wales, primarily because of its adaptability across diverse agronomic and climatic conditions. Salt-stress damage, a common occurrence in delta and coastal rice production zones, could be heightened by the interactions between high temperature and relative humidity (vapor pressure deficit--VPD). Using temporal and spatial observations spanning 107 seasons and 19 rice-growing locations throughout India with varying electrical conductivity (EC), including coastal saline, inland saline, and alkaline soils, we quantified the proportion of VPD inducing salinity damage in rice. While controlling for time-invariant factors such as trial locations, rice cultivars, and soil types, our regression analysis indicates that EC has a nonlinear detrimental effect on paddy rice yield. Our estimates suggest these yield reductions become larger at higher VPD. A one standard deviation (SD) increase in EC from its mean value is associated with 1.68% and 4.13% yield reductions at median and maximum observed VPD levels, respectively. Yield reductions increase roughly sixfold when the one SD increase is taken from the 75th percentile of EC. In combination, high EC and VPD generate near catastrophic crop loss as predicted yield approaches zero. If higher VPD levels driven by global warming materialize in conjunction with rising sea levels or salinity incursion in groundwater, this interaction becomes an important and necessary predictor of expected yield losses and global food security. PMID:25379616

  18. Effects of water management on cadmium and arsenic accumulation and dimethylarsinic acid concentrations in Japanese rice.

    PubMed

    Arao, Tomohito; Kawasaki, Akira; Baba, Koji; Mori, Shinsuke; Matsumoto, Shingo

    2009-12-15

    Rice consumption is a major source of cadmium and arsenic for the population of Asia. We investigated the effects of water management in rice paddy on levels of cadmium and arsenic in Japanese rice grains. Flooding increased arsenic concentrations in rice grains, whereas aerobic treatment increased the concentration of cadmium. Flooding for 3 weeks before and after heading was most effective in reducing grain cadmium concentrations, but this treatment increased the arsenic concentration considerably, whereas aerobic treatment during the same period was effective in reducing arsenic concentrations but increased the cadmium concentration markedly. Flooding treatment after heading was found to be more effective than flooding treatment before heading in reducing rice grain cadmium without a concomitant increase in total arsenic levels, although it increased inorganic arsenic levels. Concentrations of dimethylarsinic acid (DMA) in grain were very low under aerobic conditions but increased under flooded conditions. DMA accounted for 3-52% of the total arsenic concentration in grain grown in soil with a lower arsenic concentration and 10-80% in soil with a higher arsenic concentration. A possible explanation for the accumulation of DMA in rice grains is that DMA translocates from shoots/roots to the grains more readily than does inorganic arsenic. PMID:20000530

  19. Estimating high mosquito-producing rice fields using spectral and spatial data

    NASA Technical Reports Server (NTRS)

    Wood, B. L.; Beck, L. R.; Washino, R. K.; Hibbard, K. A.; Salute, J. S.

    1992-01-01

    The cultivation of irrigated rice provides ideal larval habitat for a number of anopheline vectors of malaria throughout the world. Anopheles freeborni, a potential vector of human malaria, is associated with the nearly 240,000 hectares of irrigated rice grown annually in Northern and Central California; therefore, this species can serve as a model for the study of rice field anopheline population dynamics. Analysis of field data revealed that rice fields with early season canopy development, that are located near bloodmeal sources (i.e., pastures with livestock) were more likely to produce anopheline larvae than fields with less developed canopies located further from pastures. Remote sensing reflectance measurements of early-season canopy development and geographic information system (GIS) measurements of distanes between rice fields and pastures with livestock were combined to distinguish between high and low mosquito-producing rice fields. Using spectral and distance measures in either a discriminant or Bayesian analysis, the identification of high mosquito-producing fields was made with 85 percent accuracy nearly two months before anopheline larval populations peaked. Since omission errors were also minimized by these approaches, they could provide a new basis for directing abatement techniques for the control of malaria vectors.

  20. Effect of cerium oxide nanoparticles on the quality of rice ( Oryza sativa L.) grains.

    PubMed

    Rico, Cyren M; Morales, Maria Isabel; Barrios, Ana Cecilia; McCreary, Ricardo; Hong, Jie; Lee, Wen-Yee; Nunez, Jose; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2013-11-27

    Despite the remarkable number of publications on the interaction of engineered nanoparticles (ENPs) with plants, knowledge of the implications of ENPs in the nutritional value of food crops is still limited. This research was performed to study the quality of rice grains harvested from plants grown in soil treated with cerium oxide nanoparticles (nCeO2). Three rice varieties (high, medium, and low amylose) were cultivated to full maturity in soil amended with nCeO2 at 0 and 500 mg kg(-1) soil. Ce accumulation, nutrient content, antioxidant property, and nutritional quality of the rice grains were evaluated. Results showed that rice grains from nCeO2-treated plants had less Fe, S, prolamin, glutelin, lauric and valeric acids, and starch. Moreover, the nCeO2 reduced in grains all antioxidant values, except flavonoids. Medium- and low-amylose varieties accumulated more Ce in grains than the high-amylose variety, but the grain quality of the medium-amylose variety showed higher sensitivity to the nCeO2 treatment. These results indicate that nCeO2 could compromise the quality of rice. To the authors' knowledge, this is the first report on the effects nCeO2 on rice grain quality. PMID:24188281

  1. Judicious use of kinetin to improve growth and yield of rice in nickel contaminated soil.

    PubMed

    Nazir, Hina; Asghar, Hafiz Naeem; Zahir, Zahir Ahmad; Akhtar, Muhammad Javed; Saleem, Muhammad

    2016-07-01

    The present study was conducted to evaluate the effect of kinetin on growth and yield of rice in the presence and absence of nickel contamination. Rice seedlings were dipped in kinetin solution (10(-3), 10(-4) and 10 M(-5)) for 2 hours and transplanted in pots having soil contaminated with nickel sulfate @ 130 mg kg(-1). Experiment was laid out according to completely randomized design with four replications. Results revealed that kinetin significantly improved growth and yield of rice grown in nickel contamination. Kinetin @ 10(-4) M showed maximum improvement in plant height, paddy yield, 1000 grain weight, number of tillers and panicles up to 9.76, 15.72, 11.77, 11.87, and 10.90%, respectively, as compared to plants grown in contaminated soil without kinetin. Kinetin also improved the uptake of nutrients (NPK) in straw and grain of plants grown in Ni contaminated soil. Plants treated with kinetin had more concentration of Ni in shoot but less in grain compared to plants grown in Ni contaminated soil without application of kinetin. The application of kinetin can reduce stress effect on plants through improvement in the biomass of plant. This strategy could be used to increase the phytoextraction of Ni from the contaminated soil. PMID:26457741

  2. Monitoring of wet season rice crop at state and national level in India using multidate synthetic aperture radar data

    NASA Astrophysics Data System (ADS)

    Chakraborty, Manab; Patnaik, Chakrapani; Panigrahy, Sushma; Parihar, Jai Singh

    2006-12-01

    Rice crop grown during the monsoon (wet) season is the most important food grain in India. The crop is grown under varied cultural and management practices. The present paper highlights the results of rice monitoring being carried out for the past five years (2001-02 to 2005-06) using multi-date RADARSAT ScanSAR Narrow-B data. 30 ScanSAR scenes covering thirteen states account for 95 percent of national crop area. 90 scenes are analysed to assess the national wet season rice crop. A stratified sampling plan is used to analyse 5*5 km segments accounting for 15 per cent of the crop area in each of the study states. A decision-rule classifier has been developed based on a Radiative Transfer (RT) model developed and calibrated using large number of rice sites in India and controlled field experiments. This procedure accounts for change in backscatter as a result of transplanting of rice and crop growth in multi-date data to classify rice areas. Results indicate more than 93 per cent accuracy of area estimation at state level and 97 per cent at national level. It is feasible to assess deviations in crop planting operation (late or early) for a given area.

  3. INTERACTION OF ELEVATED ULTRAVIOLET-B RADIATION AND CO2 ON PRODUCTIVITY AND PHOTOSYNTHETIC CHARACTERISTICS IN WHEAT, RICE, AND SOYBEAN

    EPA Science Inventory

    Wheat, rice and soybean were grown to determine if CO2-induced increases in photosynthesis biomass, and yield are modified by increases in ultraviolet-B (UV-B) radiation corresponding to stratospheric ozone depletion. he experimental conditions simulated were: a) an increase in C...

  4. Water-conserving practices in Arkansas rice production to improve soil N availability and reduce greenhouse gas emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is commonly grown in the U.S. under continual flood from early vegetative growth until shortly before harvest. Wetting and drying cycles offer potential savings in water use. In a three-year field study, wetting/drying cycles improved water use efficiency (kg grain m-3 water applied) by 22 to 4...

  5. Pore Mn²⁺ dynamics of the rhizosphere of flooded and non-flooded rice during a long wet and drying phase in two rice growing soils.

    PubMed

    Haque, K M Shamsul; Eberbach, Philip L; Weston, Leslie A; Dyall-Smith, Mike; Howitt, Julia A

    2015-09-01

    Flooded rice soils produce elevated concentrations of soluble manganous manganese (Mn(2+)) that could be potentially toxic to subsequent crops. To provide insight into how soil pore Mn(2+) changes its concentration in a rice and post rice drying soil, we used an artificial microcosm system to follow Mn(2+) concentrations in two different soil types (red sodosol and grey vertosol) and under two irrigation regimes (flooded and saturated). Soil pore water was collected from four different depths of soil (2.5 cm, 7.5 cm, 15 cm and 25 cm) and Mn(2+) concentrations were analysed during and after the rice phase over a one year cycle. Mn(2+) increased with the advancement of anaerobic conditions at all soil depths, but the concentration was higher in flooded soil compared to saturated soil. Initially, the highest concentration of Mn(2+) was found at a depth of 7.5 cm, while at the later stage of rice growth, more Mn(2+) was found in the deepest sampling depth (25 cm). Plants grown in saturated soils showed a delay in flowering of approximately 3 weeks compared to flooded cultures. Moreover, plants grown in flooded soil produced more tillers and leaf area than those grown in saturated soil. Peak concentrations of soil Mn(2+) were associated with the reproductive stage of rice growth. Mn(2+) concentrations decreased after drainage of water. In post rice soils, Mn(2+) remained elevated for some time (lag phase), and then rapidly declined. Regression analysis revealed that the process of oxidation of Mn(2+) to Mn(4+) following water drainage decreased with soil depth. PMID:25898345

  6. Characterization of Grain Quality and Starch Fine Structure of Two Japonica Rice (Oryza Sativa) Cultivars with Good Sensory Properties at Different Temperatures during the Filling Stage.

    PubMed

    Zhang, Changquan; Zhou, Lihui; Zhu, Zhengbin; Lu, Huwen; Zhou, Xingzhong; Qian, Yiting; Li, Qianfeng; Lu, Yan; Gu, Minghong; Liu, Qiaoquan

    2016-05-25

    Temperature during the growing season is a critical factor affecting grain quality. High temperatures at grain filling affect kernel development, resulting in reduced yield, increased chalkiness, reduced amylose content, and poor milling quality. Here, we investigated the grain quality and starch structure of two japonica rice cultivars with good sensory properties grown at different temperatures during the filling stage under natural field conditions. Compared to those grown under normal conditions, rice grains grown under hot conditions showed significantly reduced eating and cooking qualities, including a higher percentage of grains with chalkiness, lower protein and amylose contents, and higher pasting properties. Under hot conditions, rice starch contained reduced long-chain amylose (MW 10(7.1) to 10(7.4)) and significantly fewer short-chain amylopectin (DP 5-12) but more intermediate- (DP 13-34) and long- (DP 45-60) chain amylopectin than under normal conditions, as well as higher crystallinity and gelatinization properties. PMID:27128366

  7. Residual phosphorus and zinc influence wheat productivity under rice-wheat cropping system.

    PubMed

    Amanullah; Inamullah

    2016-01-01

    Continuous cropping of rice (Oryza sativa L.) and wheat (Triticum aestivum L.) deplete soil fertility and crop productivity. One strategy to increase crop productivity under rice-wheat system is balanced application of crop nutrients. Field experiment was conducted to assess the impact of phosphorus (0, 40, 80, 120 kg P ha(-1)) and zinc (0, 5, 10, 15 kg Zn ha(-1)) on the productivity of rice genotypes (fine and coarse) and their residual effects on the grain yield (GY) and its components (YC) of the succeeding wheat crop under rice-wheat cropping system (RWCS) in North Western Pakistan during 2011-12 and 2012-13. After rice harvest in both years, wheat variety "Siren-2010" was grown on the same layout but no additional P, K and Zn was applied to wheat crop in each year. The GY and YC of wheat significantly increased in the treatments receiving the higher P levels (120 > 80 > 40 > 0 kg P ha(-1)) and Zn (15 > 10 > 5 > 0 kg Zn ha(-1)) in the previous rice crop. The residual soil P and Zn contents after rice harvest, GY and YC of wheat increased significantly under low yielding fine genotype (B-385) as compared to the high yielding coarse genotypes (F-Malakand and Pukhraj). The residual soil P and Zn, GY and of wheat increased significantly in the second year as compared with the first year of experiment. These results confirmed strong carry over effects of both P and Zn applied to the previous rice crop on the subsequent wheat crop under RWCS. PMID:27026947

  8. Arsenic contamination of Bangladesh paddy field soils: implications for rice contribution to arsenic consumption.

    PubMed

    Meharg, Andrew A; Rahman, Md Mazibur

    2003-01-15

    Arsenic contaminated groundwater is used extensively in Bangladesh to irrigate the staple food of the region, paddy rice (Oryza sativa L.). To determine if this irrigation has led to a buildup of arsenic levels in paddy fields, and the consequences for arsenic exposure through rice ingestion, a survey of arsenic levels in paddy soils and rice grain was undertaken. Survey of paddy soils throughout Bangladesh showed that arsenic levels were elevated in zones where arsenic in groundwater used for irrigation was high, and where these tube-wells have been in operation for the longest period of time. Regression of soil arsenic levels with tube-well age was significant. Arsenic levels reached 46 microg g(-1) dry weight in the most affected zone, compared to levels below l0 microg g(-1) in areas with low levels of arsenic in the groundwater. Arsenic levels in rice grain from an area of Bangladesh with low levels of arsenic in groundwaters and in paddy soils showed that levels were typical of other regions of the world. Modeling determined, even these typical grain arsenic levels contributed considerably to arsenic ingestion when drinking water contained the elevated quantity of 0.1 mg L(-1). Arsenic levels in rice can be further elevated in rice growing on arsenic contaminated soils, potentially greatly increasing arsenic exposure of the Bangladesh population. Rice grain grown in the regions where arsenic is building up in the soil had high arsenic concentrations, with three rice grain samples having levels above 1.7 microg g(-1). PMID:12564892

  9. A rice phenomics study--phenotype scoring and seed propagation of a T-DNA insertion-induced rice mutant population.

    PubMed

    Chern, Chyr-Guan; Fan, Ming-Jen; Yu, Su-May; Hour, Ai-Ling; Lu, Po-Chang; Lin, Yao-Cheng; Wei, Fu-Jin; Huang, Sheng-Chung; Chen, Shu; Lai, Ming-Hsing; Tseng, Ching-Shan; Yen, Hsing-Mu; Jwo, Woei-Shyuan; Wu, Chen-Chia; Yang, Tung-Lung; Li, Lung-Sheng; Kuo, Yih-Cheng; Li, Su-Mien; Li, Charng-Pei; Wey, Chiu-Kai; Trisiriroj, Arunee; Lee, Hsing-Fang; Hsing, Yue-Ie C

    2007-11-01

    With the completion of the rice genome sequencing project, the next major challenge is the large-scale determination of gene function. As an important crop and a model organism, rice provides major insights into gene functions important for crop growth or production. Phenomics with detailed information about tagged populations provides a good tool for functional genomics analysis. By a T-DNA insertional mutagenesis approach, we have generated a rice mutant population containing 55,000 promoter trap and gene activation or knockout lines. Approximately 20,000 of these lines have known integration sites. The T0 and T1 plants were grown in net "houses" for two cropping seasons each year since 2003, with the mutant phenotypes recorded. Detailed data describing growth and development of these plants, in 11 categories and 65 subcategories, over the entire four-month growing season are available in a searchable database, along with the genetic segregation information and flanking sequence data. With the detailed data from more than 20,000 T1 lines and 12 plants per line, we estimated the mutation rates of the T1 population, as well the frequency of the dominant T0 mutants. The correlations among different mutation phenotypes are also calculated. Together, the information about mutant lines, their integration sites, and the phenotypes make this collection, the Taiwan Rice Insertion Mutants (TRIM), a good resource for rice phenomics study. Ten T2 seeds per line can be distributed to researchers upon request. PMID:17701278

  10. Biological Control Activities of Rice-Associated Bacillus sp. Strains against Sheath Blight and Bacterial Panicle Blight of Rice.

    PubMed

    Shrestha, Bishnu K; Karki, Hari Sharan; Groth, Donald E; Jungkhun, Nootjarin; Ham, Jong Hyun

    2016-01-01

    Potential biological control agents for two major rice diseases, sheath blight and bacterial panicle blight, were isolated from rice plants in this study. Rice-associated bacteria (RABs) isolated from rice plants grown in the field were tested for their antagonistic activities against the rice pathogens, Rhizoctonia solani and Burkholderia glumae, which cause sheath blight and bacterial panicle blight, respectively. Twenty-nine RABs were initially screened based on their antagonistic activities against both R. solani and B. glumae. In follow-up retests, 26 RABs of the 29 RABs were confirmed to have antimicrobial activities, but the rest three RABs did not reproduce any observable antagonistic activity against R. solani or B. glumae. According to16S rDNA sequence identity, 12 of the 26 antagonistic RABs were closest to Bacillus amyloliquefaciens, while seven RABs were to B. methylotrophicus and B, subtilis, respectively. The 16S rDNA sequences of the three non-antagonistic RABs were closest to Lysinibacillus sphaericus (RAB1 and RAB12) and Lysinibacillus macroides (RAB5). The five selected RABs showing highest antimicrobial activities (RAB6, RAB9, RAB16, RAB17S, and RAB18) were closest to B. amyloliquefaciens in DNA sequence of 16S rDNA and gyrB, but to B. subtilis in that of recA. These RABs were observed to inhibit the sclerotial germination of R. solani on potato dextrose agar and the lesion development on detached rice leaves by artificial inoculation of R. solani. These antagonistic RABs also significantly suppressed the disease development of sheath blight and bacterial panicle blight in a field condition, suggesting that they can be potential biological control agents for these rice diseases. However, these antagonistic RABs showed diminished disease suppression activities in the repeated field trial conducted in the following year probably due to their reduced antagonistic activities to the pathogens during the long-term storage in -70C, suggesting that

  11. Biological Control Activities of Rice-Associated Bacillus sp. Strains against Sheath Blight and Bacterial Panicle Blight of Rice

    PubMed Central

    Shrestha, Bishnu K.; Karki, Hari Sharan; Groth, Donald E.; Jungkhun, Nootjarin; Ham, Jong Hyun

    2016-01-01

    Potential biological control agents for two major rice diseases, sheath blight and bacterial panicle blight, were isolated from rice plants in this study. Rice-associated bacteria (RABs) isolated from rice plants grown in the field were tested for their antagonistic activities against the rice pathogens, Rhizoctonia solani and Burkholderia glumae, which cause sheath blight and bacterial panicle blight, respectively. Twenty-nine RABs were initially screened based on their antagonistic activities against both R. solani and B. glumae. In follow-up retests, 26 RABs of the 29 RABs were confirmed to have antimicrobial activities, but the rest three RABs did not reproduce any observable antagonistic activity against R. solani or B. glumae. According to16S rDNA sequence identity, 12 of the 26 antagonistic RABs were closest to Bacillus amyloliquefaciens, while seven RABs were to B. methylotrophicus and B, subtilis, respectively. The 16S rDNA sequences of the three non-antagonistic RABs were closest to Lysinibacillus sphaericus (RAB1 and RAB12) and Lysinibacillus macroides (RAB5). The five selected RABs showing highest antimicrobial activities (RAB6, RAB9, RAB16, RAB17S, and RAB18) were closest to B. amyloliquefaciens in DNA sequence of 16S rDNA and gyrB, but to B. subtilis in that of recA. These RABs were observed to inhibit the sclerotial germination of R. solani on potato dextrose agar and the lesion development on detached rice leaves by artificial inoculation of R. solani. These antagonistic RABs also significantly suppressed the disease development of sheath blight and bacterial panicle blight in a field condition, suggesting that they can be potential biological control agents for these rice diseases. However, these antagonistic RABs showed diminished disease suppression activities in the repeated field trial conducted in the following year probably due to their reduced antagonistic activities to the pathogens during the long-term storage in -70C, suggesting that

  12. Biochar amendment to lead-contaminated soil: Effects on fluorescein diacetate hydrolytic activity and phytotoxicity to rice.

    PubMed

    Tan, Xiaofei; Liu, Yunguo; Gu, Yanling; Zeng, Guangming; Hu, Xinjiang; Wang, Xin; Hu, Xi; Guo, Yiming; Zeng, Xiaoxia; Sun, Zhichao

    2015-09-01

    The amendment effects of biochar on total microbial activity was measured by fluorescein diacetate (FDA) hydrolytic activity, and phytotoxicity in Pb(II)-contaminated soils was examined by the application of 4 different biochars to soil, with rice as a test plant. The FDA hydrolytic activities of biochar-amended soils were much higher than that of the control. The survival rate of rice in lead-contaminated biochar-amended soils showed significant improvement over the control, especially for bamboo biochar-amended soil (93.3%). In addition, rice grown in lead-contaminated control sediment displayed lower biomass production than that in biochar-amended soil. The immobilization of Pb(II) and the positive effects of biochar amendment on soil microorganisms may account for these effects. The results suggest that biochar may have an excellent ability to mitigate the toxic effects of Pb(II) on soil microorganisms and rice. PMID:25900615

  13. Soil Incorporation of Silica-Rich Rice Husk Decreases Inorganic Arsenic in Rice Grain.

    PubMed

    Seyfferth, Angelia L; Morris, Andrew H; Gill, Rattandeep; Kearns, Kelli A; Mann, Jessica N; Paukett, Michelle; Leskanic, Corey

    2016-05-18

    Arsenic decreases rice yield, and inorganic grain As threatens human health; thus, strategies to decrease rice As are critically needed. Increased plant-available silica (Si) can decrease rice As, yet the source of Si matters. Rice husk, an underutilized and Si-rich byproduct of rice production that contains less labile C and an order of magnitude less As than rice straw, may be an economically viable Si resource to decrease rice As, yet the impact of rice husk incorporation on As in the rice-soil nexus has not been reported. This proof-of-concept study shows that rice husk incorporation to soil (1% w/w) decreases inorganic grain As by 25-50% without negatively affecting grain Cd, yield, or dissolved CH4 levels. Rice husk is a critical yet perhaps overlooked resource to improve soil quality through enhanced nutrient availability and attenuate human health risks through consumption of As-laden grain. PMID:27109244

  14. Reverse genetics in rice using Tos17.

    PubMed

    Mieulet, Delphine; Diévart, Anne; Droc, Gaëtan; Lanau, Nadège; Guiderdoni, Emmanuel

    2013-01-01

    Transposon of Oryza sativa 17 (Tos17), a Ty1-Copia Class I retroelement, is one of the few active retroelements identified in rice, the main cereal crop of human consumption and the model genome for cereals. Tos17 exists in two copies in the standard Nipponbare japonica genome (n = 12 and 379 Mb). Tos17 copies are inactive in the plant grown under normal conditions. However, the copy located on chromosome 7 can be activated upon tissue culture. Plants regenerated from 3- and 5-month-old tissue cultures harbor, respectively, an average of 3.5 and 8 newly transposed copies that are stably inserted at new positions in the genome. Due to its favorable features, Tos17 has been extensively used for insertion mutagenesis of the model genome and 31,403 sequence indexed inserts harbored by regenerants/T-DNA plants are available in the databases. The corresponding seed stocks can be ordered from the laboratories which generated them. Both forward genetics and reverse genetics approaches using these lines have allowed the deciphering of gene function in rice. We report here two protocols for ascertaining the presence of a Tos17 insertion in a gene of interest among R2/T2 seeds received from Tos17 mutant stock centers: The first protocol is PCR-based and allows the identification of azygous, heterozygous and homozygous plants among progenies segregating the insertion. The second protocol is based on DNA blot analysis and can be used to identify homozygous plants carrying the Tos17 copy responsible for gene disruption while cleaning the mutant background from other unwitting mutagen inserts. PMID:23918431

  15. Rice scene radiation research plan

    NASA Technical Reports Server (NTRS)

    Heilman, J.

    1982-01-01

    Data requirements, tasks to be accomplished, and the technical approaches to be used in identifying the characteristics of rice for crop inventories are listed as well as methods for estimating crop development and assessing its conditions.

  16. Rice Reoviruses in Insect Vectors.

    PubMed

    Wei, Taiyun; Li, Yi

    2016-08-01

    Rice reoviruses, transmitted by leafhopper or planthopper vectors in a persistent propagative manner, seriously threaten the stability of rice production in Asia. Understanding the mechanisms that enable viral transmission by insect vectors is a key to controlling these viral diseases. This review describes current understanding of replication cycles of rice reoviruses in vector cell lines, transmission barriers, and molecular determinants of vector competence and persistent infection. Despite recent breakthroughs, such as the discoveries of actin-based tubule motility exploited by viruses to overcome transmission barriers and mutually beneficial relationships between viruses and bacterial symbionts, there are still many gaps in our knowledge of transmission mechanisms. Advances in genome sequencing, reverse genetics systems, and molecular technologies will help to address these problems. Investigating the multiple interaction systems among the virus, insect vector, insect symbiont, and plant during natural infection in the field is a central topic for future research on rice reoviruses. PMID:27296147

  17. Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species.

    PubMed

    Norton, Gareth J; Adomako, Eureka E; Deacon, Claire M; Carey, Anne-Marie; Price, Adam H; Meharg, Andrew A

    2013-06-01

    Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic. PMID:23466730

  18. Arsenic in soil and irrigation water affects arsenic uptake by rice: complementary insights from field and pot studies.

    PubMed

    Dittmar, Jessica; Voegelin, Andreas; Maurer, Felix; Roberts, Linda C; Hug, Stephan J; Saha, Ganesh C; Ali, M Ashraf; Badruzzaman, A Borhan M; Kretzschmar, Ruben

    2010-12-01

    Groundwater rich in arsenic (As) is extensively used for dry season boro rice cultivation in Bangladesh, leading to long-term As accumulation in soils. This may result in increasing levels of As in rice straw and grain, and eventually, in decreasing rice yields due to As phytotoxicity. In this study, we investigated the As contents of rice straw and grain over three consecutive harvest seasons (2005-2007) in a paddy field in Munshiganj, Bangladesh, which exhibits a documented gradient in soil As caused by annual irrigation with As-rich groundwater since the early 1990s. The field data revealed that straw and grain As concentrations were elevated in the field and highest near the irrigation water inlet, where As concentrations in both soil and irrigation water were highest. Additionally, a pot experiment with soils and rice seeds from the field site was carried out in which soil and irrigation water As were varied in a full factorial design. The results suggested that both soil As accumulated in previous years and As freshly introduced with irrigation water influence As uptake during rice growth. At similar soil As contents, plants grown in pots exhibited similar grain and straw As contents as plants grown in the field. This suggested that the results from pot experiments performed at higher soil As levels can be used to assess the effect of continuing soil As accumulation on As content and yield of rice. On the basis of a recently published scenario of long-term As accumulation at the study site, we estimate that, under unchanged irrigation practice, average grain As concentrations will increase from currently ∼0.15 mg As kg(-1) to 0.25-0.58 mg As kg(-1) by the year 2050. This translates to a 1.5-3.8 times higher As intake by the local population via rice, possibly exceeding the provisional tolerable As intake value defined by FAO/WHO. PMID:21043519

  19. Agriculture and the promotion of insect pests: rice cultivation in river floodplains and malaria vectors in The Gambia

    PubMed Central

    Jarju, Lamin BS; Fillinger, Ulrike; Green, Clare; Louca, Vasilis; Majambere, Silas; Lindsay, Steven W

    2009-01-01

    Background Anthropogenic modification of natural habitats can create conditions in which pest species associated with humans can thrive. In order to mitigate for these changes, it is necessary to determine which aspects of human management are associated with the promotion of those pests. Anopheles gambiae, the main Africa malaria vector, often breeds in rice fields. Here the impact of the ancient practice of 'swamp rice' cultivation, on the floodplains of the Gambia River, on the production of anopheline mosquitoes was investigated. Methods Routine surveys were carried out along 500 m transects crossing rice fields from the landward edge of the floodplains to the river during the 2006 rainy season. Aquatic invertebrates were sampled using area samplers and emergence traps and fish sampled using nets. Semi-field experiments were used to investigate whether nutrients used for swamp rice cultivation affected mosquito larval abundance. Results At the beginning of the rainy season rice is grown on the landward edge of the floodplain; the first area to flood with fresh water and one rich in cattle dung. Later, rice plants are transplanted close to the river, the last area to dry out on the floodplain. Nearly all larval and adult stages of malaria vectors were collected 0–100 m from the landward edge of the floodplains, where immature rice plants were grown. These paddies contained stagnant freshwater with high quantities of cattle faeces. Semi-field studies demonstrated that cattle faeces nearly doubled the number of anopheline larvae compared with untreated water. Conclusion Swamp rice cultivation creates ideal breeding sites for malaria vectors. However, only those close to the landward edge harboured vectors. These sites were productive since they were large areas of standing freshwater, rich in nutrients, protected from fish, and situated close to human habitation, where egg-laying mosquitoes from the villages had short distances to fly. The traditional practice

  20. Storage stability of flour-blasted brown rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brown rice was blasted with rice flour rather than sand in a sand blaster to make microscopic nicks and cuts so that water can easily penetrate into the brown rice endosperm and cook the rice in a shorter time. The flour-blasted American Basmati brown rice, long grain brown rice, and parboiled long...

  1. Differentiation of weedy traits in ALS-resistant red rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice is a weedy form of cultivated rice (Oryza sativa) that competes aggressively with rice in the southern U.S., reduces yields and contaminates rice grains. The introduction of ClearfieldTM rice, a nontransgenic, herbicide-resistant rice cultivar a decade ago has led to increased use of imazet...

  2. Rice Photosynthetic Productivity and PSII Photochemistry under Nonflooded Irrigation

    PubMed Central

    He, Haibing; Yang, Ru; Jia, Biao; Chen, Lin; Fan, Hua; Cui, Jing; Yang, Dong; Li, Menglong; Ma, Fu-Yu

    2014-01-01

    Nonflooded irrigation is an important water-saving rice cultivation technology, but little is known on its photosynthetic mechanism. The aims of this work were to investigate photosynthetic characteristics of rice during grain filling stage under three nonflooded irrigation treatments: furrow irrigation with plastic mulching (FIM), furrow irrigation with nonmulching (FIN), and drip irrigation with plastic mulching (DI). Compared with the conventional flooding (CF) treatment, those grown in the nonflooded irrigation treatments showed lower net photosynthetic rate (PN), lower maximum quantum yield (Fv/Fm), and lower effective quantum yield of PSII photochemistry (ΦPSII). And the poor photosynthetic characteristics in the nonflooded irrigation treatments were mainly attributed to the low total nitrogen content (TNC). Under non-flooded irrigation, the PN, Fv/Fm, and ΦPSII significantly decreased with a reduction in the soil water potential, but these parameters were rapidly recovered in the DI and FIM treatments when supplementary irrigation was applied. Moreover, The DI treatment always had higher photosynthetic productivity than the FIM and FIN treatments. Grain yield, matter translocation, and dry matter post-anthesis (DMPA) were the highest in the CF treatment, followed by the DI, FIM, and FIN treatments in turn. In conclusion, increasing nitrogen content in leaf of rice plants could be a key factor to improve photosynthetic capacity in nonflooded irrigation. PMID:24741364

  3. Comparative analysis of two emerging rice seed bacterial pathogens.

    PubMed

    Fory, P A; Triplett, L; Ballen, C; Abello, J F; Duitama, J; Aricapa, M G; Prado, G A; Correa, F; Hamilton, J; Leach, J E; Tohme, J; Mosquera, G M

    2014-05-01

    Seed sterility and grain discoloration limit rice production in Colombia and several Central American countries. In samples of discolored rice seed grown in Colombian fields, the species Burkholderia glumae and B. gladioli were isolated, and field isolates were compared phenotypically. An artificial inoculation assay was used to determine that, although both bacterial species cause symptoms on rice grains, B. glumae is a more aggressive pathogen, causing yield reduction and higher levels of grain sterility. To identify putative virulence genes differing between B. glumae and B. gladioli, four previously sequenced genomes of Asian and U.S. strains of the two pathogens were compared with each other and with two draft genomes of Colombian B. glumae and B. gladioli isolates generated for this study. Whereas previously characterized Burkholderia virulence factors are highly conserved between the two species, B. glumae and B. gladioli strains are predicted to encode distinct groups of genes encoding type VI secretion systems, transcriptional regulators, and membrane-sensing proteins. This study shows that both B. glumae and B. gladioli can threaten grain quality, although only one species affects yield. Furthermore, genotypic differences between the two strains are identified that could contribute to disease phenotypic differences. PMID:24261408

  4. Detection algorithm for multiple rice seeds images

    NASA Astrophysics Data System (ADS)

    Cheng, F.; Ying, Y. B.

    2006-10-01

    The objective of this research is to develop a digital image analysis algorithm for detection of multiple rice seeds images. The rice seeds used for this study involved a hybrid rice seed variety. Images of multiple rice seeds were acquired with a machine vision system for quality inspection of bulk rice seeds, which is designed to inspect rice seeds on a rotating disk with a CCD camera. Combining morphological operations and parallel processing gave improvements in accuracy, and a reduction in computation time. Using image features selected based on classification ability; a highly acceptable defects classification was achieved when the algorithm was implemented for all the samples to test the adaptability.

  5. Kennedy at Rice University

    NASA Technical Reports Server (NTRS)

    1962-01-01

    President Kennedy speaks before a crowd of 35,000 people at Rice University in the football field. The following are excerpts from his speech. ' ...We set sail on his new sea because there is a new knowledge to be gained, and new rights to be won, and they must be won and used for the progress of all people. ...Whether it will become a force for good or ill depends on man, and only if the United States occupies a position of pre-eminence can we help decide whether this new ocean will be a sea of peace or a new terrifying theater of war. But I do say space can be explored and mastered without feeding the fires of war, without repeating the mistakes that man has made with extending his writ around this globe of ours. ...There is no strife, no prejudice, no national conflict in outer space as yet. Its conquest deserves the best of all mankind, and its opportunity for peaceful cooperation may never come again. But why, some say the Moon? Why choose this as our goal? And they may well ask, why climb the highest mountian? Why - 35 years ago - why fly the Atlantic? Why does Rice play Texas? We choose to go to the Moon, we choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one in which we intend to win, and the others too.'

  6. Kennedy at Rice University

    NASA Technical Reports Server (NTRS)

    1962-01-01

    President Kennedy speaks before a crowd of 35,000 people at Rice University in the football field. The following are excerpts from his speech. ' ...We set sail on his new sea because there is a new knowledge to begained, and new rights to be won, and they must be won and used for the progress of all people. Whether it will become a force for good or ill depends on man, and only if the United States occupies a position of pre-eminence can we help decide whether this new ocean will be a sea of peace or a new terrifying theater of war. But I do say space can be explored and mastered without feeding the fires of war, without repeating the mistakes that man has made with extending his wirt around this globe of ours. There is no strife, no prejudice, no national conflict in outer space as yet. Its conquest deserves the best of all mankind, and its opportunity for peaceful cooperation may never come again. But why, some say the Moon? Why choose this as our goal? And they may well ask, why climb the highest mountain? Why 35 years ago why fly the Atlantic? Why does Rice play Texas? We choose to go to the Moon, we choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one in which we attend to win, and the others , too.'

  7. Outcrossing potential between U.S. red rice (Oryza sativa) and Chinese indica rice (Oryza sativa) lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice in southern U.S. rice fields remains a widespread, economically challenging problem despite nearly a decade of rice production systems that include true-breeding rice cultivars and indica-derived hybrid rice with resistance to imazethapyr. Both of these herbicide-resistant rice systems hav...

  8. Red rice (Oryza sativa L.) emergence characteristics and influence on rice (O. sativa) yield at different planting dates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cultivated rice yield losses due to red rice infestation vary by cultivar, red rice density, and duration of interference. The competition effects of red rice could be influenced further by emergence characteristics, red rice biotype, and planting time of cultivated rice. We aimed to characterize th...

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

    PubMed Central

    Park, Hyun Ji; Lee, Sang Sook; You, Young Nim; Yoon, Dae Hwa; Kim, Beom-Gi; Ahn, Jun Cheul; Cho, Hye Sun

    2013-01-01

    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. PMID:23485991

  10. Development and characterisation of metformin loaded spray dried Bora rice microspheres.

    PubMed

    Sharma, Hemanta Kumar; Mohapatra, Jadavesh; Nath, Lila Kanta

    2013-01-01

    Bora rice, a glutinous rice, is grown in Assam (a north eastern state of India) and is used traditionally for various purposes. The rationale of this study was to prepare and to assess Metformin loaded mucoadhesive spray dried microspheres using locally grown Bora rice powder. Metformin loaded microspheres were prepared using Bora rice and sodium alginate by spray drying method. For the study of the consequence of parameters of spray drier on the properties of microspheres, parameters such as aspirator flow rate, temperature, feed flow rate and concentration of the spray solution were changed. The in-vitro release properties were also studied. Almost spherical microspheres were obtained with significant swelling and mucoadhesivity. Dissolution study was carried out in phosphate buffer (pH 7.4) for 7 hrs. It was also noted to possess good mucoadhesive in such a way that about 90% of microspheres remained adherent on the surface of intestinal mucosa of pig skin. The total amount of drug released from microspheres after 7 hr. was 80%. The release of drug was not affected by the changes in parameters but was affected when sodium alginate concentration was changed. It was observed that microsphere properties changed as the parameters were changed. Smaller particles were obtained when the concentration of the spray solution, aspirator flow rate, the temperature difference between inlet and outlet and feed flow rate were lower. PMID:23261723

  11. Processing Conditions, Rice Properties, Health and Environment

    PubMed Central

    Roy, Poritosh; Orikasa, Takahiro; Okadome, Hiroshi; Nakamura, Nobutaka; Shiina, Takeo

    2011-01-01

    Rice is the staple food for nearly two-thirds of the world’s population. Food components and environmental load of rice depends on the rice form that is resulted by different processing conditions. Brown rice (BR), germinated brown rice (GBR) and partially-milled rice (PMR) contains more health beneficial food components compared to the well milled rice (WMR). Although the arsenic concentration in cooked rice depends on the cooking methods, parboiled rice (PBR) seems to be relatively prone to arsenic contamination compared to that of untreated rice, if contaminated water is used for parboiling and cooking. A change in consumption patterns from PBR to untreated rice (non-parboiled), and WMR to PMR or BR may conserve about 43–54 million tons of rice and reduce the risk from arsenic contamination in the arsenic prone area. This study also reveals that a change in rice consumption patterns not only supply more food components but also reduces environmental loads. A switch in production and consumption patterns would improve food security where food grains are scarce, and provide more health beneficial food components, may prevent some diseases and ease the burden on the Earth. However, motivation and awareness of the environment and health, and even a nominal incentive may require for a method switching which may help in building a sustainable society. PMID:21776212

  12. Molecular dynamics of interactions of rice with rice blast and sheath blight pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an effort to develop the molecular strategies to control rice (Oryzae sativa) diseases, molecular interactions of rice with rice blast [Magnaporthe oryzae, formerly (Magnaporthe grisea] and sheath blight (Rhizoctonia solani) fungi were analyzed. The interaction of rice with M. oryzae follows a b...

  13. Factors influencing ALS-resistant gene transfer from CL (tm) rice to red rice.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice (Oryza sativa L.) is hard to control due to its genetic similarity to cultivated rice. Herbicide-resistant Clearfield ™ (CL) rice now offers an excellent option for red rice control. However, sustainability of CL technology at the producers’ level will be dictated by various factors. Promi...

  14. The impact of planting date on management of the rice water weevil in Louisiana rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rice water weevil, Lissorhoptrus oryzophilus, is the most destructive insect pest of rice in the United States. Early planting of rice to avoid damaging infestations of the rice water weevil has long been suggested as a management tactic. A five-year study was conducted to characterize the influ...

  15. Diversity of global rice markets and the science required for consumer-targeted rice breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With the ever-increasing global demand for high quality rice in both local production regions and with Western consumers, we have a strong desire to understand better the importance of different quality traits that make up the rice grain and obtain a full picture of rice quality demographics. Rice ...

  16. Genetic diversity for rice grain mineral concentrations observed among genetically and geographically giverse rice accessions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With about half of the world’s people dependent on rice as their main food source, improving the nutritional value of rice could have major impact on human health. While rice in the USA is often artificially fortified, natural enhancement of the rice grain’s nutritional value, i.e. from genetic impr...

  17. Volatiles induction in rice stink bug host grasses and rice plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice stink bug (RSB), Oebalus pugnax F., is an important pest of heading rice in the United States. Little is known about plant volatiles production following herbivory by the rice stink bug. RSB feeding induced volatiles production in different RSB host grasses and rice varieties, and may help expl...

  18. Biogeochemical cycling of Si in a California rice cropping system

    NASA Astrophysics Data System (ADS)

    Seyfferth, A.; Kocar, B. D.; Lee, J.; Fendorf, S.

    2012-12-01

    Silicon is the second most abundant element in the earth's crust, but the number of studies on the biogeochemical cycling of Si does not reflect its environmental ubiquity. While not an "essential" plant nutrient, Si is important for many plants, particularly monocots, for structural integrity and protection against disease and environmental stress. For rice, Si fertilization with N and P increases yield significantly more than N and P alone. While total Si in soil is high, much of this Si is tied up in the crystal lattice of primary and secondary minerals and is only slowly released through chemical weathering. Thus, plant-available Si may be limited particularly in highly weathered soils in humid environments where long-term chemical weathering has lead to desilicification of the soils (e.g., in Southeast Asia where most rice is grown). In such Si-depleted environments, the biocycling of Si through decaying plant litter (i.e., phytoliths) and subsequent plant uptake has proven an important component of the terrestrial biogeochemical cycling of Si. Here, we investigate the dynamics of Si cycling over a two-year period in a rice paddy in Northern California where soil incorporation of harvested rice straw has impacted the terrestrial biogeochemical cycling of Si. We use Ge/Si ratios in pore-waters to infer the contribution of chemical weathering vs. dissolution of plant phytoliths on the plant-available Si pool. We found that the Ge/Si ratios change over the growing and fallow seasons reflecting different rates of Si release through phytolith dissolution and plant uptake.

  19. Can the co-cultivation of rice and fish help sustain rice production?

    PubMed

    Hu, Liangliang; Zhang, Jian; Ren, Weizheng; Guo, Liang; Cheng, Yongxu; Li, Jiayao; Li, Kexin; Zhu, Zewen; Zhang, Jiaen; Luo, Shiming; Cheng, Lei; Tang, Jianjun; Chen, Xin

    2016-01-01

    Because rice feeds half of the world's population, a secure global food supply depends on sustainable rice production. Here we test whether the co-cultivation of rice and fish into one "rice-fish system" (RFS; fish refers to aquatic animals in this article) could help sustain rice production. We examined intensive and traditional RFSs that have been widely practiced in China. We found that rice yields did not decrease when fish yield was below a threshold value in each intensive RFS. Below the thresholds, moreover, fish yields in intensive RFSs can be substantially higher than those in traditional RFS without reducing rice yield. Relative to rice monoculture, the use of fertilizer-nitrogen and pesticides decreased, and the farmers' net income increased in RFSs. The results suggest that RFSs can help sustain rice production, and suggest that development of co-culture technologies (i.e. proper field configuration for fish and rice) is necessary to achieve the sustainability. PMID:27349875

  20. Significance, progress and prospects for research in simplified cultivation technologies for rice in China

    PubMed Central

    HUANG, M.; IBRAHIM, MD.; XIA, B.; ZOU, Y.

    2011-01-01

    SUMMARY Simplified cultivation technologies for rice have become increasingly attractive in recent years in China because of their social, economical and environmental benefits. To date, several simplified cultivation technologies, such as conventional tillage and seedling throwing (CTST), conventional tillage and direct seeding (CTDS), no-tillage and seedling throwing (NTST), no-tillage and direct seeding (NTDS) and no-tillage and transplanting (NTTP), have been developed in China. Most studies have shown that rice grown under each of these simplified cultivation technologies can produce a grain yield equal to or higher than traditional cultivation (conventional tillage and transplanting). Studies that have described the influences of agronomic practices on yield formation of rice under simplified cultivation have demonstrated that optimizing agronomy practices would increase the efficiencies of simplified cultivation systems. Further research is needed to optimize the management strategies for CTST, CTDS and NTST rice which have developed quickly in recent years, to strengthen basic research for those simplified cultivation technologies that are rarely used at present (such as NTTP and NTDS), to select and breed cultivars suitable for simplified cultivation and to compare the practicability and effectiveness of different simplified cultivation technologies in different rice production regions. PMID:22505773

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

    PubMed

    Bandaru, Varaprasad; Daughtry, Craig S; Codling, Eton E; Hansen, David J; White-Hansen, Susan; Green, Carrie E

    2016-01-01

    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. PMID:27322304

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

    PubMed Central

    Bandaru, Varaprasad; Daughtry, Craig S.; Codling, Eton E.; Hansen, David J.; White-Hansen, Susan; Green, Carrie E.

    2016-01-01

    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. PMID:27322304

  3. Diversity and functional traits of culturable microbiome members, including cyanobacteria in the rice phyllosphere.

    PubMed

    Venkatachalam, S; Ranjan, K; Prasanna, R; Ramakrishnan, B; Thapa, S; Kanchan, A

    2016-07-01

    The diversity and abundance of culturable microbiome members of the rice phyllosphere was investigated using cv. Pusa Punjab Basmati 1509. Both diversity and species richness of bacteria were significantly higher in plants in pots in a semi-controlled environment than those in fields. Application of fertilisers reduced both diversity and species richness in field-grown plants under a conventional flooded system of rice intensification (SRI) and in dry-seeded rice (DSR) modes. Sequence analyses of 16S rDNA of culturable bacteria, those selected after amplified ribosomal DNA restriction analysis (ARDRA), showed the dominance of α-proteobacteria (35%) and actinobacteria (38%); Pantoea, Exiguobacterium and Bacillus were common among the culturable phyllospheric bacteria. About 34% of 83 culturable bacterial isolates had higher potential (>2 μg·ml(-1) ) for indole acetic acid production in the absence of tryptophan. Interestingly, the phyllosphere bacterial isolates from the pot experiment had significantly higher potential for nitrogen fixation than isolates from the field experiment. Enrichment for cyanobacteria showed both unicellular forms and non-heterocystous filaments under aerobic as well as anaerobic conditions. PCR-DGGE analysis of these showed that aerobic and anaerobic conditions as well as the three modes of cultivation of rice in the field strongly influenced the number and abundance of phylotypes. The adaptability and functional traits of these culturable microbiome members suggest enormous diversity in the phyllosphere, including potential for plant growth promotion, which was also significantly influenced by the different methods of growing rice. PMID:26849835

  4. Effect of elevated CO2 on chlorpyriphos degradation and soil microbial activities in tropical rice soil.

    PubMed

    Adak, Totan; Munda, Sushmita; Kumar, Upendra; Berliner, J; Pokhare, Somnath S; Jambhulkar, N N; Jena, M

    2016-02-01

    Impact of elevated CO2 on chlorpyriphos degradation, microbial biomass carbon, and enzymatic activities in rice soil was investigated. Rice (variety Naveen, Indica type) was grown under four conditions, namely, chambered control, elevated CO2 (550 ppm), elevated CO2 (700 ppm) in open-top chambers and open field. Chlorpyriphos was sprayed at 500 g a.i. ha(-1) at maximum tillering stage. Chlorpyriphos degraded rapidly from rice soils, and 88.4% of initially applied chlorpyriphos was lost from the rice soil maintained under elevated CO2 (700 ppm) by day 5 of spray, whereas the loss was 80.7% from open field rice soil. Half-life values of chlorpyriphos under different conditions ranged from 2.4 to 1.7 days with minimum half-life recorded with two elevated CO2 treatments. Increased CO2 concentration led to increase in temperature (1.2 to 1.8 °C) that played a critical role in chlorpyriphos persistence. Microbial biomass carbon and soil enzymatic activities specifically, dehydrogenase, fluorescien diacetate hydrolase, urease, acid phosphatase, and alkaline phosphatase responded positively to elevated CO2 concentrations. Generally, the enzyme activities were highly correlated with each other. Irrespective of the level of CO2, short-term negative influence of chlorpyriphos was observed on soil enzymes till day 7 of spray. Knowledge obtained from this study highlights that the elevated CO2 may negatively influence persistence of pesticide but will have positive effects on soil enzyme activities. PMID:26790432

  5. Arsenic Concentrations in Rice and Associated Health Risks Along the Upper Mekong Delta, Cambodia

    NASA Astrophysics Data System (ADS)

    Barragan, L.; Seyfferth, A.; Fendorf, S.

    2011-12-01

    The consumption of arsenic contaminated food, such as rice, can be a significant portion of daily arsenic exposure, even for populations already exposed through drinking water. While arsenic contamination of rice grains has been documented in parts of Southern Asia, (e.g. Bangladesh), little research has been conducted on arsenic contamination of Cambodian-grown rice. We collected rice plant samples at various locations within the upper Mekong River Delta near Phnom Penh, Cambodia, and we analyzed total arsenic concentrations in plant digests of grains, husk, and straw. In addition, we used CaCl2-, DTPA-, and oxalate-extractable arsenic to define plant-available soil pools. We found variability of arsenic concentration in the plants, with grain arsenic ranging from 0.046 to 0.214 μg g-1; other researchers have shown that concentrations higher than 0.1 μg g-1 could be a concern for human health. Although more extensive sampling is needed to assess the risk of arsenic exposure from rice consumption on a country-wide basis, our work clearly illustrates the risk within regions of the Mekong Delta.

  6. Comparative Morphophysiological Analyses and Molecular Profiling Reveal Pi-Efficient Strategies of a Traditional Rice Genotype

    PubMed Central

    Mehra, Poonam; Pandey, Bipin K.; Giri, Jitender

    2016-01-01

    Phosphate (Pi) deficiency severely affects crop yield. Modern high yielding rice genotypes are sensitive to Pi deficiency whereas traditional rice genotypes are naturally compatible with low Pi ecosystems. However, the underlying molecular mechanisms for low Pi tolerance in traditional genotypes remain largely elusive. To delineate the molecular mechanisms for low Pi tolerance, two contrasting rice genotypes, Dular (low Pi tolerant), and PB1 (low Pi sensitive), have been selected. Comparative morphophysiological, global transcriptome and lipidome analyses of root and shoot tissues of both genotypes grown under Pi deficient and sufficient conditions revealed potential low Pi tolerance mechanisms of the traditional genotype. Most of the genes associated with enhanced internal Pi utilization (phospholipid remobilization) and modulation of root system architecture (RSA) were highly induced in the traditional rice genotype, Dular. Higher reserves of phospholipids and greater accumulation of galactolipids under low Pi in Dular indicated it has more efficient Pi utilization. Furthermore, Dular also maintained greater root growth than PB1 under low Pi, resulting in larger root surface area due to increased lateral root density and root hair length. Genes involved in enhanced low Pi tolerance of the traditional genotype can be exploited to improve the low Pi tolerance of modern high yielding rice cultivars. PMID:26779218

  7. Different farming and water regimes in Italian rice fields affect arbuscular mycorrhizal fungal soil communities.

    PubMed

    Lumini, Erica; Vallino, Marta; Alguacil, Maria M; Romani, Marco; Bianciotto, Valeria

    2011-07-01

    Arbuscular mycorrhizal fungi (AMF) comprise one of the main components of soil microbiota in most agroecosystems. These obligate mutualistic symbionts colonize the roots of most plants, including crop plants. Many papers have indicated that different crop management practices could affect AMF communities and their root colonization. However, there is little knowledge available on the influence of conventional and low-input agriculture on root colonization and AMF molecular diversity in rice fields. Two different agroecosystems (continuous conventional high-input rice monocropping and organic farming with a five-year crop rotation) and two different water management regimes have been considered in this study. Both morphological and molecular analyses were performed. The soil mycorrhizal potential, estimated using clover trap cultures, was high and similar in the two agroecosystems. The diversity of the AMF community in the soil, calculated by means of PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) and 18S rDNA sequencing on clover trap cultures roots, was higher for the organic cultivation. The rice roots cultivated in the conventional agrosystem or under permanent flooding showed no AMF colonization, while the rice plants grown under the organic agriculture system showed typical mycorrhization patterns. Considered together, our data suggest that a high-input cropping system and conventional flooding depress AMF colonization in rice roots and that organic managements could help maintain a higher diversity of AMF communities in soil. PMID:21830711

  8. Do soil Fe transformation and secretion of low-molecular-weight organic acids affect the availability of Cd to rice?

    PubMed

    Chen, Xue; Yang, Yazhou; Liu, Danqing; Zhang, Chunhua; Ge, Ying

    2015-12-01

    The bioavailability of cadmium (Cd) to rice may be complicated by chemical and biological factors in the rhizosphere. The aim of this work is to investigate how soil iron (Fe) redox transformations and low-molecular-weight organic acid (LMWOA) exudation from root affect Cd accumulation in rice. Two soils (a paddy soil and a saline soil) with different physicochemical properties were used in this study. Soil redox conditions were changed by flooding and addition of organic matter (OM). Two days after the soil treatments, rice seedlings were transplanted in a vermiculite-soil system and grown for 10 days. We measured pH and Eh, LMWOA, Fe and Cd contents in rice, and their fractions in the soils and vermiculite. Cadmium accumulation in rice declined in both soils upon the flooding and OM treatment. Iron dissolution in the paddy soil and its deposition in the rhizosphere significantly increased upon the OM addition, but the concentration of Fe plaque on the rice root significantly declined. Conversely, although Fe transformed into less active fractions in the saline soil, Fe accumulation on the surface and in the tissue of root was considerably enhanced. The secretion of LMWOA was remarkably induced when the OM was amended in the saline soil, but the same effect was not observed in the paddy soil. Reduction of Cd uptake by rice could be attributed to different factors in the two soils. For the paddy soil, the lowered Cd bioavailability was likely due to the competition of Fe and Cd for the binding sites on the vermiculite surface. For the saline soil, however, rice responded to the low Fe mobility through more LMWOA exudation and Fe plaque formation, and their increases could explain the decrease of rice Cd. PMID:26260840

  9. Dissipation and effects of tricyclazole on soil microbial communities and rice growth as affected by amendment with alperujo compost.

    PubMed

    García-Jaramillo, M; Redondo-Gómez, S; Barcia-Piedras, J M; Aguilar, M; Jurado, V; Hermosín, M C; Cox, L

    2016-04-15

    The presence of pesticides in surface and groundwater has grown considerably in the last decades as a consequence of the intensive farming activity. Several studies have shown the benefits of using organic amendments to prevent losses of pesticides from runoff or leaching. A particular soil from the Guadalquivir valley was placed in open air ponds and amended at 1 or 2% (w/w) with alperujo compost (AC), a byproduct from the olive oil industry. Tricyclazole dissipation, rice growth and microbial diversity were monitored along an entire rice growing season. An increase in the net photosynthetic rate of Oryza sativa plants grown in the ponds with AC was observed. These plants produced between 1100 and 1300kgha(-1) more rice than plants from the unamended ponds. No significant differences were observed in tricyclazole dissipation, monitored for a month in soil, surface and drainage water, between the amended and unamended ponds. The structure and diversity of bacteria and fungi communities were also studied by the use of the polymerase chain reaction denaturing gel electrophoresis (PCR-DGGE) from DNA extracted directly from soil samples. The banding pattern was similar for all treatments, although the density of bands varied throughout the time. Apparently, tricyclazole did not affect the structure and diversity of bacteria and fungi communities, and this was attributed to its low bioavailability. Rice cultivation under paddy field conditions may be more efficient under the effects of this compost, due to its positive effects on soil properties, rice yield, and soil microbial diversity. PMID:26849328

  10. Delving deeper into technological innovations to understand differences in rice quality.

    PubMed

    Calingacion, Mariafe; Fang, Lu; Quiatchon-Baeza, Lenie; Mumm, Roland; Riedel, Arthur; Hall, Robert D; Fitzgerald, Melissa

    2015-12-01

    Increasing demand for better quality rice varieties, which are also more suited to growth under sub-optimal cultivation conditions, is driving innovation in rice research. Here we have used a multi-disciplinary approach, involving SNP-based genotyping together with phenotyping based on yield analysis, metabolomic analysis of grain volatiles, and sensory panel analysis to determine differences between two contrasting rice varieties, Apo and IR64. Plants were grown under standard and drought-induced conditions. Results revealed important differences between the volatile profiles of the two rice varieties and we relate these differences to those perceived by the sensory panel. Apo, which is the more drought tolerant variety, was less affected by the drought condition concerning both sensory profile and yield; IR64, which has higher quality but is drought sensitive, showed greater differences in these characteristics in response to the two growth conditions. Metabolomics analyses using GCxGC-MS, followed by multivariate statistical analyses of the data, revealed a number of discriminatory compounds between the varieties, but also effects of the difference in cultivation conditions. Results indicate the complexity of rice volatile profile, even of non-aromatic varieties, and how metabolomics can be used to help link changes in aroma profile with the sensory phenotype. Our outcomes also suggest valuable multi-disciplinary approaches which can be used to help define the aroma profile in rice, and its underlying genetic background, in order to support breeders in the generation of improved rice varieties combining high yield with high quality, and tolerance of both these traits to climate change. PMID:26054242

  11. Pathways and relative contributions to arsenic volatilization from rice plants and paddy soil.

    PubMed

    Jia, Yan; Huang, Hai; Sun, Guo-Xin; Zhao, Fang-Jie; Zhu, Yong-Guan

    2012-08-01

    Recent studies have shown that higher plants are unable to methylate arsenic (As), but it is not known whether methylated As species taken up by plants can be volatilized. Rice (Oryza sativa L.) plants were grown axenically or in a nonsterile soil using a two-chamber system. Arsenic transformation and volatilization were investigated. In the axenic system, uptake of As species into rice roots was in the order of arsenate (As(V)) > monomethylarsonic acid (MMAs(V)) > dimethylarsinic acid (DMAs(V)) > trimethylarsine oxide (TMAs(V)O), but the order of the root-to-shoot transport index (Ti) was reverse. Also, volatilization of trimethylarsine (TMAs) from rice plants was detected when plants were treated with TMAs(V)O but not with As(V), DMAs(V), or MMAs(V). In the soil culture, As was volatilized mainly from the soil. Small amounts of TMAs were also volatilized from the rice plants, which took up DMAs(V), MMAs(V), and TMAs(V)O from the soil solution. The addition of dried distillers grain (DDG) to the soil enhanced As mobilization into the soil solution, As methylation and volatilization from the soil, as well as uptake of different As species and As volatilization from the rice plants. Results show that rice is able to volatilize TMAs after the uptake of TMAs(V)O but not able to convert inorganic As, MMAs(V) or DMAs(V) into TMAs and that the extent of As volatilization from rice plants was much smaller than that from the flooded soil. PMID:22724924

  12. Impact of Rice Paddy Areas Decrease on Local Climate over Taiwan

    NASA Astrophysics Data System (ADS)

    Lo, M. H.; Wen, W. H.; Chen, C. C.

    2014-12-01

    Agricultural irrigation practice is one of the important anthropogenic processes in the land surface modeling. Irrigation can decrease local surface temperature with alternating surface energy partitioning. Rice paddy is the major food crop in Asian monsoon region and rice is grown under flooded conditions during the growing season; hence, the rice paddy can be considered as an open water body, which has more impacts on the surface energy budget than other cropland does. In this study, we explore how the rice paddy area changes affect Taiwan's regional climate from both observational data and numerical modeling exercise. The Weather Research and Forecasting (WRF) model is utilized to explore impacts of rice paddy area changes on the regional climate, and energy and water budget changes. In addition, temperature datasets from six automatic weather stations in the northern Taiwan and two stations in the southern Taiwan are analyzed in this study to explore how the Daily Temperature Range (DTR) changes with the decreased rice paddy areas. Previous studies show that due to the urban heat island effect, aerosol direct and indirect effects, and global warming, the DTR has decreased in the past 4 decades observed from most of the weather stations around Taiwan. However, the declined rice paddy area may increase the DTR with higher Bowen ratio during the daytime. Preliminary results show that DTR is decreased in weather stations near the urban area, but increased in weather stations near fallow areas in the past 20 years. It shows that different land use changes may have opposite impacts on local and regional climate.

  13. Refinement of light-responsive transcript lists using rice oligonucleotide arrays: evaluation of gene-redundancy.

    PubMed

    Jung, Ki-Hong; Dardick, Christopher; Bartley, Laura E; Cao, Peijian; Phetsom, Jirapa; Canlas, Patrick; Seo, Young-Su; Shultz, Michael; Ouyang, Shu; Yuan, Qiaoping; Frank, Bryan C; Ly, Eugene; Zheng, Li; Jia, Yi; Hsia, An-Ping; An, Kyungsook; Chou, Hui-Hsien; Rocke, David; Lee, Geun Cheol; Schnable, Patrick S; An, Gynheung; Buell, C Robin; Ronald, Pamela C

    2008-01-01

    Studies of gene function are often hampered by gene-redundancy, especially in organisms with large genomes such as rice (Oryza sativa). We present an approach for using transcriptomics data to focus functional studies and address redundancy. To this end, we have constructed and validated an inexpensive and publicly available rice oligonucleotide near-whole genome array, called the rice NSF45K array. We generated expression profiles for light- vs. dark-grown rice leaf tissue and validated the biological significance of the data by analyzing sources of variation and confirming expression trends with reverse transcription polymerase chain reaction. We examined trends in the data by evaluating enrichment of gene ontology terms at multiple false discovery rate thresholds. To compare data generated with the NSF45K array with published results, we developed publicly available, web-based tools (www.ricearray.org). The Oligo and EST Anatomy Viewer enables visualization of EST-based expression profiling data for all genes on the array. The Rice Multi-platform Microarray Search Tool facilitates comparison of gene expression profiles across multiple rice microarray platforms. Finally, we incorporated gene expression and biochemical pathway data to reduce the number of candidate gene products putatively participating in the eight steps of the photorespiration pathway from 52 to 10, based on expression levels of putatively functionally redundant genes. We confirmed the efficacy of this method to cope with redundancy by correctly predicting participation in photorespiration of a gene with five paralogs. Applying these methods will accelerate rice functional genomics. PMID:18836531

  14. Rice disease research in organic production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic rice production has increased significantly in the U. S. with 35,000 acres currently under production. Texas organic rice acreage has been increasing steadily over the last 10 years with acreage in 2009 reaching 16,000, accounting for approximately 10% of the total Texas rice acreage. Contro...

  15. Is ALL Rice Bran Created Equal?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of whole grain rice is increasing in the U.S. This increase is likely due to increased consumer awareness of the importance of whole grains in the diet. Whole grain rice is superior nutritionally compared to milled rice because, except for carbohyrates, it contains more phytochemicals an...

  16. Understanding rice heterosis using deep sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heterosis is a complex biological phenomenon where the offspring show better performance compared to the inbred parents. Although rice breeders have used heterosis in hybrid rice production for nearly 40 years, the genetic and molecular mechanism underlying the heterosis in rice is still poorly und...

  17. Rice functionality, starch structure and the genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Through collaborative efforts among USDA scientists at Beaumont, Texas, we have gained in-depth knowledge of how rice functionality, i.e. the texture of the cooked rice, rice processing properties, and starch gelatinization temperature, are associated with starch-synthesis genes and starch structure...

  18. SHEATH BLIGHT RESISTANCE IN SOUTHERN RICE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sheath blight is a serious fungal disease problem in southern US rice production, making it necessary for rice farmers to diligently use fungicides for its control. There are no long grain rice varieties adapted to commercial production in the southern US that have adequate resistance to sheath bli...

  19. U.S. Rice: Enhancing human health.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A vision of the U.S. rice industry is to improve human health through the development of germplasm and technologies for products that capture the unique nutritional benefits of the rice grain. This paper gives an overview of U.S. rice production and markets. New product trends and introductions in...

  20. New market opportunities for rice grains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breeding efforts for rice have been focusing on increasing yield and improving quality (milling yield and grain quality), while maintaining cooked rice sensory properties to meet consumer preferences. These breeding targets will no doubt continue as the main foci for the rice industry. However, the ...

  1. Protein Crystals Grown in Space

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A collage of protein and virus crystals, many of which were grown on the U.S. Space Shuttle or Russian Space Station, Mir. The crystals include the proteins canavalin; mouse monoclonal antibody; a sweet protein, thaumatin; and a fungal protease. Viruses are represented here by crystals of turnip yellow mosaic virus and satellite tobacco mosaic virus. The crystals are photographed under polarized light (thus causing the colors) and range in size from a few hundred microns in edge length up to more than a millimeter. All the crystals are grown from aqueous solutions and are useful for X-ray diffraction analysis. Credit: Dr. Alex McPherson, University of California, Irvine.

  2. Rice bran proteins: properties and food uses.

    PubMed

    Prakash, J

    1996-07-01

    Rice bran, a good source of protein and fat, is at present underutilized as a food material. The potential of producing rice bran at the global level is 27.3 million t. The presence of enzyme lipase in rice bran causes rapid deterioration of oil to free fatty acids and glycerol. Various stabilization techniques involving heat treatment, low-temperature storage, chemical treatment, control of relative humidity during storage, and simultaneous milling and extraction were evolved to inactivate lipase. Multiple forms of rice bran lipase have been identified. Fractional classification of proteins reveals a high percentage of albumins and globulins. Proteins can be extracted from full-fat or defatted rice bran by alkaline extraction and acid or heat precipitation. Extraction procedures influence the protein content of concentrates, which ranged from 19.4 to 76.1% in concentrates from full-fat rice bran and 17.5 to 85.0% in concentrates from defatted rice bran. The PER of rice bran ranges from 1.59 to 2.04 and that of protein concentrates from 1.99 to 2.19. Available lysine contents of protein concentrates ranged from 54 to 58.8%. The essential amino acid profiles of protein concentrates indicate that threonine and isoleucine are limiting amino acids. Various functional properties of rice bran protein concentrates have also been investigated that are known to be influenced by drying technique and stabilization treatment of rice bran. Rice bran has been used in food as full-fat rice bran, defatted rice bran, and in the form of rice bran oil and protein concentrates. Full-fat and defatted rice bran have been used in bakery products, breakfast cereals, wafers, as a protein supplement, binder ingredients for meats and sausages, and as a beverage base. Incorporation of protein concentrates have been studied in bread, beverages, confections, and weaning foods. PMID:8841730

  3. Rice, indica (Oryza sativa L.).

    PubMed

    Hiei, Yukoh; Ishida, Yuji; Komari, Toshihiko

    2015-01-01

    Indica varieties, which are generally recalcitrant to tissue culture and transformation, occupy 80 % of rice cultivation area in the world. Therefore, transformation method for indica rice must be improved greatly so that global rice production would take full advantage of cutting-edge biotechnology. An efficient protocol for indica transformation mediated by Agrobacterium tumefaciens is hereby described. Immature embryos collected from plants in a greenhouse are cocultivated with A. tumefaciens after pretreatment with heat and centrifuging. The protocol was successfully tested in many elite indica cultivars such as IR8, IR24, IR58025B, IR64, IR72, Suweon 258, and Nanjing 11, yielding between 5 and 15 of independent transgenic plants per immature embryo. The use of immature embryos is recommended because gene transfer to them could be much more efficient and much less genotype dependent than gene transfer to callus. PMID:25300838

  4. Tillering and panicle branching genes in rice.

    PubMed

    Liang, Wei-hong; Shang, Fei; Lin, Qun-ting; Lou, Chen; Zhang, Jing

    2014-03-01

    Rice (Oryza sativa L.) is one of the most important staple food crops in the world, and rice tillering and panicle branching are important traits determining grain yield. Since the gene MONOCULM 1 (MOC 1) was first characterized as a key regulator in controlling rice tillering and branching, great progress has been achieved in identifying important genes associated with grain yield, elucidating the genetic basis of yield-related traits. Some of these important genes were shown to be applicable for molecular breeding of high-yielding rice. This review focuses on recent advances, with emphasis on rice tillering and panicle branching genes, and their regulatory networks. PMID:24345551

  5. Iron Biofortification of Myanmar Rice

    PubMed Central

    Aung, May Sann; Masuda, Hiroshi; Kobayashi, Takanori; Nakanishi, Hiromi; Yamakawa, Takashi; Nishizawa, Naoko K.

    2013-01-01

    Iron (Fe) deficiency elevates human mortality rates, especially in developing countries. In Myanmar, the prevalence of Fe-deficient anemia in children and pregnant women are 75 and 71%, respectively. Myanmar people have one of the highest per capita rice consumption rates globally. Consequently, production of Fe-biofortified rice would likely contribute to solving the Fe-deficiency problem in this human population. To produce Fe-biofortified Myanmar rice by transgenic methods, we first analyzed callus induction and regeneration efficiencies in 15 varieties that are presently popular because of their high-yields or high-qualities. Callus formation and regeneration efficiency in each variety was strongly influenced by types of culture media containing a range of 2,4-dichlorophenoxyacetic acid concentrations. The Paw San Yin variety, which has a high-Fe content in polished seeds, performed well in callus induction and regeneration trials. Thus, we transformed this variety using a gene expression cassette that enhanced Fe transport within rice plants through overexpression of the nicotianamine synthase gene HvNAS1, Fe flow to the endosperm through the Fe(II)-nicotianamine transporter gene OsYSL2, and Fe accumulation in endosperm by the Fe storage protein gene SoyferH2. A line with a transgene insertion was successfully obtained. Enhanced expressions of the introduced genes OsYSL2, HvNAS1, and SoyferH2 occurred in immature T2 seeds. The transformants accumulated 3.4-fold higher Fe concentrations, and also 1.3-fold higher zinc concentrations in T2 polished seeds compared to levels in non-transgenic rice. This Fe-biofortified rice has the potential to reduce Fe-deficiency anemia in millions of Myanmar people without changing food habits and without introducing additional costs. PMID:23750162

  6. Incorporating rice residues into paddy soils affects methylmercury accumulation in rice.

    PubMed

    Zhu, Huike; Zhong, Huan; Wu, Jialu

    2016-06-01

    Paddy fields are characterized by frequent organic input (e.g., fertilization and rice residue amendment), which may affect mercury biogeochemistry and bioaccumulation. To explore potential effects of rice residue amendment on methylmercury (MMHg) accumulation in rice, a mercury-contaminated paddy soil was amended with rice root (RR), rice straw (RS) or composted rice straw (CS), and planted with rice. Incorporating RS or CS increased grain MMHg concentration by 14% or 11%. The observed increases could be attributed to the elevated porewater MMHg levels and thus enhanced MMHg uptake by plants, as well as increased MMHg translocation to grain within plants. Our results indicated for the first time that rice residue amendment could significantly affect MMHg accumulation in rice grain, which should be considered in risk assessment of MMHg in contaminated areas. PMID:26974480

  7. Transport of Soil Halides through Rice Paddies: A Viable Mechanism for Rapid Dispersion of the Soil Halide Reservoir

    NASA Astrophysics Data System (ADS)

    Redeker, K. R.; Manley, S.; Wang, N.; Cicerone, R.

    2002-05-01

    On short time scales (1-10 years) soil halide concentrations have been assumed to be primarily driven by leaching and deposition processes. Recent results however, have shown that terrestrial plants volatilize soil halides in the form of methyl halides. Emissions of methyl chloride, methyl bromide and methyl iodide represent major pathways for delivery of inorganic halogen radicals to the atmosphere. Inorganic halogen radicals destroy ozone in the stratosphere and modify the oxidative capacity of the lower atmosphere. We have previously shown that rice paddies emit methyl halides and that emissions depend on growth stage of the rice plant as well as field water management. We show here that rice grown in a greenhouse at UCI is capable of volatilizing and/or storing up to 30%, 5%, and 10% of the available chloride, bromide and iodide within the top meter of soil. The percent of plant tissue halide volatilized as methyl halide over the course of the season is calculated to be 0.05%, 0.25% and 85.0% for chloride, bromide and iodide. We compare our greenhouse soil halide concentrations to other commercial rice fields around the world and estimate the e-folding time for soil halides within each region. We suggest that rice agriculture is the driving removal mechanism for halides within rice paddies and that terrestrial plants play a larger role in global cycling of halides than previously estimated.

  8. Increase of As release and phytotoxicity to rice seedlings in As-contaminated paddy soils by Si fertilizer application.

    PubMed

    Lee, Chia-Hsing; Huang, Hsuan-Han; Syu, Chien-Hui; Lin, Tzu-Huei; Lee, Dar-Yuan

    2014-07-15

    Silicon (Si) was shown to be able to reduce arsenic (As) uptake by rice in hydroponic culture or in low As soils using high Si application rates. However, the effect of Si application on As uptake of rice grown in As-contaminated soils using Si fertilizer recommendation rate has not been investigated. In this study, the effect of Si application using Si fertilizer recommendation rate on As release and phytotoxicity in soils with different properties and contents of As was examined. The results show that the concentrations of As in soil solutions increased after Si applications due to competitive adsorption between As and Si on soil solids and the Si concentrations in soil solutions were also elevated to beneficial levels for rice growth. The rice seedlings accumulated more As and its growth was inhibited by Si application in As contaminated/spiked soils. The results indicate that there is an initial aggravation in As toxicity before the beneficial effects of Si fertilizing to rice were revealed when Si application based on fertilizer recommendation rate to As-contaminated paddy soils. Therefore, for As-contaminated paddy soils with high levels of As, the application of Si fertilizer could result in increasing As phytotoxicity and uptake by rice. PMID:24892775

  9. Validation of revised DNDC model for methane emissions from irrigated rice fields in Thailand and sensitivity analysis of key factors

    NASA Astrophysics Data System (ADS)

    Smakgahn, Kruamas; Fumoto, Tamon; Yagi, Kazuyuki

    2009-06-01

    The original Denitrification-Decomposition (DNDC) model and a revised version were tested against data from field observations of methane (CH4) emissions from irrigated rice fields in Thailand. The revised DNDC model, which was modified for use in Japanese rice fields by revising the crop growth and soil biogeochemical submodels, yielded better simulation results than the original model. In most cases, daily CH4 fluxes predicted by the revised DNDC model agreed well with observations. Seasonal CH4 emissions simulated by the revised model showed significantly higher correlation with observations than those obtained with the original model. Errors in the simulation appear to have resulted from uncertainties in both the input parameters and the model descriptions. Sensitivity analysis revealed that the revised DNDC model is highly sensitive to the concentration of reducible soil Fe, the rate of rice straw incorporation, and rice root biomass. Therefore, uncertainties in these factors may strongly affect the prediction of CH4 emissions. These results suggest that for reliable prediction of CH4 emissions from Thai rice fields, further work is needed to improve the estimates of reducible soil Fe, to quantify the rate of straw incorporation, and to parameterize the crop submodel for the dominant rice varieties grown in Thailand.

  10. Weedy (red) rice: An emerging constraint to global rice production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ongoing increases in the human population necessitate that rice will continue to be an essential aspect of food security for the 21st century. While production must increase in the coming decades to meet demand, such increases will be accompanied by diminished natural resources and rising productio...

  11. Insights into molecular mechanism of blast resistance in weedy rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weedy rice is a serious pest in direct-seeded rice fields in the U.S. and worldwide. Under suitable conditions, weedy rice can reduce crop yields up to 70%. However, weedy rice may carry novel disease resistance genes. Rice blast disease caused by the fungus Magnaporthe oryzae is a major disease wo...

  12. Translational genomics-rice research in agriculture research service

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although the US accounts for only approximately 1.6 % of the total world rice production, it provides about 15% of the rice in world trade, and its rice is known for its high quality. Rice is a model for genomic study of monocots and thus, numerous broad-spectrum research activities involving rice ...

  13. Rice brans, rice bran oils, and rice hulls: composition, food and industrial uses, and bioactivities in humans, animals, and cells.

    PubMed

    Friedman, Mendel

    2013-11-13

    Rice plants produce bioactive rice brans and hulls that have been reported to have numerous health-promoting effects in cells, animals, and humans. The main objective of this review is to consolidate and integrate the widely scattered information on the composition and the antioxidative, anti-inflammatory, and immunostimulating effects of rice brans from different rice cultivars, rice bran oils derived from rice brans, rice hulls, liquid rice hull smoke derived from rice hulls, and some of their bioactive compounds. As part of this effort, this paper also presents brief summaries on the preparation of health-promoting foods including bread, corn flakes, frankfurters, ice cream, noodles, pasta, tortillas, and zero-trans-fat shortening as well as industrial products such bioethanol and biodiesel fuels. Also covered are antibiotic, antiallergic, anticarcinogenic, antidiabetic, cardiovascular, allelochemical, and other beneficial effects and the mechanisms of the bioactivities. The results show that food-compatible and safe formulations with desirable nutritional and biological properties can be used to develop new multifunctional foods as well as bioethanol and biodiesel fuel. The overlapping aspects are expected to contribute to a better understanding of the potential impact of the described health-promoting potential of the rice-derived brans, oils, and hulls in food and medicine. Such an understanding will enhance nutrition and health and benefit the agricultural and industrial economies. PMID:24175575

  14. Agriculture Education. Soybeans and Rice.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary students enrolled in one or two semester-long courses in agricultural education. The guide presents units of study in the following areas: (1) soybeans, (2) rice, and (3) orientation. Each of the 17 units of instruction follows a typical format: terminal objective, specific…

  15. The impact of herbicide-resistant rice technology on phenotypic diversity and population structure of United States weedy rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of imazethapyr herbicide-resistant (HR) Clearfield® rice (Oryza sativa L.) to control weedy rice has increased in the past 12 years to comprise about 60% of rice acreage in Arkansas, where 43% of rice in the USA was planted in 2013. To assess the impact of HR cultivated rice on herbicide res...

  16. Rice production in relation to soil quality under different rice-based cropping systems

    NASA Astrophysics Data System (ADS)

    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

  17. Aerobic rice mechanization: techniques for crop establishment

    NASA Astrophysics Data System (ADS)

    Khusairy, K. M.; Ayob, H.; Chan, C. S.; Fauzi, M. I. Mohamed; Mohamad Fakhrul, Z. O.; Shahril Shah, G. S. M.; Azlan, O.; Rasad, M. A.; Hashim, A. M.; Arshad, Z.; E, E. Ibrahim; Saifulizan, M. N.

    2015-12-01

    Rice being the staple food crops, hundreds of land races in it makes the diversity of rice crops. Aerobic rice production was introduced which requires much less water input to safeguard and sustain the rice production and conserve water due to decreasing water resources, climatic changes and competition from urban and industrial users. Mechanization system plays an important role for the success of aerobic rice cultivation. All farming activities for aerobic rice production are run on aerobic soil conditions. Row seeder mechanization system is developed to replace conventional seeding technique on the aerobic rice field. It is targeted for small and the large scale aerobic rice farmers. The aero - seeder machine is used for the small scale aerobic rice field, while the accord - seeder is used for the large scale aerobic rice field. The use of this mechanization machine can eliminate the tedious and inaccurate seeding operations reduce labour costs and increases work rate. The machine is easy to operate and it can increase crop establishment rate. It reduce missing hill, increasing planting and crop with high yield can be produce. This machine is designed for low costs maintenance and it is easy to dismantle and assemble during maintenance and it is safe to be used.

  18. An Innovative Modeling and Measurement Approach to Improve Rice Water Use Efficiency in California

    NASA Astrophysics Data System (ADS)

    Montazar, A.; Little, C.; Rejmanek, H.; Tindula, G.; Snyder, R. L.

    2014-12-01

    California is amongst the top rice producing states in the USA, and more than 95 percent of California's rice is grown in the Sacramento Valley. Based on older literature, the rice water requirement (ETc), ranges between 914 and 1,100 mm. In this study, the actual rice water requirement was measured using the residual of the energy balance method over three paddy rice fields during 2011-2013 seasons in the Sacramento Valley. Net radiation and ground heat flux density were measured, and both eddy covariance (EC) and the surface renewal (SR) technique were employed to determine the sensible heat flux density. The surface renewal method uses high frequency temperature measurements from fine wire thermocouples above the canopy. Mean amplitude and duration of the ramps over half hour periods were determined using a structure function and the characteristics are employed to estimate the direction and magnitude of sensible heat flux using the ratio of the amplitude to the ramp duration as the change in temperature per unit time and the volumetric heat capacity of the air to estimate the magnitude of the heat flux. In the study, 76.2 mm diameter chromel-constantan thermocouples were used to measure high frequency temperature at 10 Hz. The results indicate that there is considerable variability in rice water use both spatially and temporally. The average three-year measured ET of the experimental fields located in Butte County was 734 and 725 mm; and in Colusa County was 771 mm. A typical crop coefficient (Kc) curve was derived from the measured ETc and reference ET (ETo) data. Spatial estimates of monthly climate data from the Sacramento Valley were used to calculate monthly mean ETo, and smooth curve fits of the monthly data gave estimates of typical daily ETo. The daily ETc was calculated as the product of ETo and Kc, and seasonal ETc was calculated by summing the daily ETc values. The results reveal that the seasonal rice ETc was less than earlier estimates. Surface

  19. OsWRKY74, a WRKY transcription factor, modulates tolerance to phosphate starvation in rice

    PubMed Central

    Dai, Xiaoyan; Wang, Yuanyuan; Zhang, Wen-Hao

    2016-01-01

    The WRKY transcription factor family has 109 members in the rice genome, and has been reported to be involved in the regulation of biotic and abiotic stress in plants. Here, we demonstrated that a rice OsWRKY74 belonging to group III of the WRKY transcription factor family was involved in tolerance to phosphate (Pi) starvation. OsWRKY74 was localized in the nucleus and mainly expressed in roots and leaves. Overexpression of OsWRKY74 significantly enhanced tolerance to Pi starvation, whereas transgenic lines with down-regulation of OsWRKY74 were sensitive to Pi starvation. Root and shoot biomass, and phosphorus (P) concentration in rice OsWRKY74-overexpressing plants were ~16% higher than those of wild-type (WT) plants in Pi-deficient hydroponic solution. In soil pot experiments, >24% increases in tiller number, grain weight and P concentration were observed in rice OsWRKY74-overexpressing plants compared to WT plants when grown in P-deficient medium. Furthermore, Pi starvation-induced changes in root system architecture were more profound in OsWRKY74-overexpressing plants than in WT plants. Expression patterns of a number of Pi-responsive genes were altered in the OsWRKY74-overexpressing and RNA interference lines. In addition, OsWRKY74 may also be involved in the response to deficiencies in iron (Fe) and nitrogen (N) as well as cold stress in rice. In Pi-deficient conditions, OsWRKY74-overexpressing plants exhibited greater accumulation of Fe and up-regulation of the cold-responsive genes than WT plants. These findings highlight the role of OsWRKY74 in modulation of Pi homeostasis and potential crosstalk between P starvation and Fe starvation, and cold stress in rice. PMID:26663563

  20. Mutualistic fungal endophytes produce phytohormones and organic acids that promote japonica rice plant growth under prolonged heat stress*

    PubMed Central

    Waqas, Muhammad; Khan, Abdul Latif; Shahzad, Raheem; Ullah, Ihsan; Khan, Abdur Rahim; Lee, In-Jung

    2015-01-01

    This study identifies the potential role in heat-stress mitigation of phytohormones and other secondary metabolites produced by the endophytic fungus Paecilomyces formosus LWL1 in japonica rice cultivar Dongjin. The japonica rice was grown in controlled chamber conditions with and without P. formosus LWL1 under no stress (NS) and prolonged heat stress (HS) conditions. Endophytic association under NS and HS conditions significantly improved plant growth attributes, such as plant height, fresh weight, dry weight, and chlorophyll content. Furthermore, P. formosus LWL1 protected the rice plants from HS compared with controls, indicated by the lower endogenous level of stress-signaling compounds such as abscisic acid (25.71%) and jasmonic acid (34.57%) and the increase in total protein content (18.76%–33.22%). Such fungal endophytes may be helpful for sustainable crop production under high environmental temperatures. PMID:26642184

  1. Systemic Infection of Maize, Sorghum, Rice, and Beet Seedlings with Fumonisin-Producing and Nonproducing Fusarium verticillioides Strains.

    PubMed

    Dastjerdi, Raana; Karlovsky, Petr

    2015-12-01

    Two fumonisin-nonproducing strains of Fusarium verticillioides and their fumonisin producing progenitors were tested for aggressiveness toward maize, sorghum, rice, and beetroot seedlings grown under greenhouse conditions. None of the plants showed obvious disease symptoms after root dip inoculation. Fungal biomass was determined by species-specific real-time PCR. No significant (P = 0.05) differences in systemic colonization were detected between the wild type strains and mutants not producing fumonisins. F. verticillioides was not detected in any of the non-inoculated control plants. The fungus grew from roots to the first two internodes/leaves of maize, rice and beet regardless of fumonisin production. The systemic growth of F. verticillioides in sorghum was limited. The results showed that fumonisin production was not required for the infection of roots of maize, rice and beet by F. verticillioides. PMID:26672472

  2. Systemic Infection of Maize, Sorghum, Rice, and Beet Seedlings with Fumonisin-Producing and Nonproducing Fusarium verticillioides Strains

    PubMed Central

    Dastjerdi, Raana; Karlovsky, Petr

    2015-01-01

    Two fumonisin-nonproducing strains of Fusarium verticillioides and their fumonisin producing progenitors were tested for aggressiveness toward maize, sorghum, rice, and beetroot seedlings grown under greenhouse conditions. None of the plants showed obvious disease symptoms after root dip inoculation. Fungal biomass was determined by species-specific real-time PCR. No significant (P = 0.05) differences in systemic colonization were detected between the wild type strains and mutants not producing fumonisins. F. verticillioides was not detected in any of the non-inoculated control plants. The fungus grew from roots to the first two internodes/leaves of maize, rice and beet regardless of fumonisin production. The systemic growth of F. verticillioides in sorghum was limited. The results showed that fumonisin production was not required for the infection of roots of maize, rice and beet by F. verticillioides. PMID:26672472

  3. Detection and quantification of trace elements in rice and rice products using x-ray fluorescence

    NASA Astrophysics Data System (ADS)

    Foran, Kelly A.; Fleming, David E. B.

    2015-12-01

    We used X-ray fluorescence (XRF) to examine the presence of arsenic (As) and other trace elements (manganese, iron, nickel, copper, and zinc) in rice and rice products. A portable XRF analyzer was used to test samples, and amplitudes for the analyzed elements were identified in the resulting data. The detection limit of the system was sufficiently low to detect As in some rice and rice product samples.

  4. Physicochemical, thermal and pasting characteristics of gamma irradiated rice starches.

    PubMed

    Gul, Khalid; Singh, A K; Sonkawade, R G

    2016-04-01

    Starches isolated from two recently released rice cultivars (PR 121 and PR 116) grown in sub-tropical climates of Punjab, India were subjected to gamma irradiation at 0, 2, and 10kGy doses using a Co(60) irradiator source. Physicochemical, thermal, pasting, and morphological properties were studied. Irradiation resulted in a significant decrease in apparent amylose content, swelling power and pasting properties. Carboxyl content and solubility increased with irradiation. The granule morphology was evaluated using scanning electron microscope, particle size analyzer and light microscope. Irradiation resulted in formation of small size granules. Granules were irregular and polyhedral in shape. The granule morphology and A-type X-ray diffraction pattern were not altered by irradiation. PMID:26778155

  5. Temperature modulates the cell wall mechanical properties of rice coleoptiles by altering the molecular mass of hemicellulosic polysaccharides

    NASA Technical Reports Server (NTRS)

    Nakamura, Yukiko; Wakabayashi, Kazuyuki; Hoson, Takayuki

    2003-01-01

    The present study was conducted to investigate the mechanism inducing the difference in the cell wall extensibility of rice (Oryza sativa L. cv. Koshihikari) coleoptiles grown under various temperature (10-50 degrees C) conditions. The growth rate and the cell wall extensibility of rice coleoptiles exhibited the maximum value at 30-40 degrees C, and became smaller as the growth temperature rose or dropped from this temperature range. The amounts of cell wall polysaccharides per unit length of coleoptile increased in coleoptiles grown at 40 degrees C, but not at other temperature conditions. On the other hand, the molecular size of hemicellulosic polysaccharides was small at temperatures where the cell wall extensibility was high (30-40 degrees C). The autolytic activities of cell walls obtained from coleoptiles grown at 30 and 40 degrees C were substantially higher than those grown at 10, 20 and 50 degrees C. Furthermore, the activities of (1-->3),(1-->4)-beta-glucanases extracted from coleoptile cell walls showed a similar tendency. When oat (1-->3),(1-->4)-beta-glucans with high molecular mass were incubated with the cell wall enzyme preparations from coleoptiles grown at various temperature conditions, the extensive molecular mass downshifts were brought about only by the cell wall enzymes obtained from coleoptiles grown at 30-40 degrees C. There were close correlations between the cell wall extensibility and the molecular mass of hemicellulosic polysaccharides or the activity of beta -glucanases. These results suggest that the environmental temperature regulates the cell wall extensibility of rice coleoptiles by modifying mainly the molecular mass of hemicellulosic polysaccharides. Modulation of the activity of beta-glucanases under various temperature conditions may be involved in the alteration of the molecular size of hemicellulosic polysaccharides.

  6. Oil Production from Yarrowia lipolytica Po1g Using Rice Bran Hydrolysate

    PubMed Central

    Tsigie, Yeshitila Asteraye; Wang, Chun-Yuan; Kasim, Novy S.; Diem, Quy-Do; Huynh, Lien-Huong; Ho, Quoc-Phong; Truong, Chi-Thanh; Ju, Yi-Hsu

    2012-01-01

    The purpose of this study was to produce microbial oil from Yarrowia lipolytica Po1g grown in defatted rice bran hydrolysate. After removing oil from rice bran by Soxhlet extraction, the bran is subjected to acid hydrolysis with various sulfuric acid concentrations (1–4% v/v), reaction times (1–8 h), and reaction temperatures (60–120°C). The optimal conditions for maximum total sugar production from the hydrolysate were found to be 3% sulfuric acid at 90°C for 6 h. Glucose was the predominant sugar (43.20 ± 0.28 g/L) followed by xylose (4.93 ± 0.03 g/L) and arabinose (2.09 ± 0.01 g/L). The hydrolysate was subsequently detoxified by neutralization to reduce the amount of inhibitors such as 5-hydroxymethylfurfural (HMF) and furfural to increase its potential as a medium for culturing Y. lipolytica Po1g. Dry cell mass and lipid content of Y. lipolytica Po1g grown in detoxified defatted rice bran hydrolysate (DRBH) under optimum conditions were 10.75 g/L and 48.02%, respectively. PMID:22496604

  7. Transcriptome profiling characterizes phosphate deficiency effects on carbohydrate metabolism in rice leaves.

    PubMed

    Park, Myoung Ryoul; Baek, So-Hyeon; de Los Reyes, Benildo G; Yun, Song Joong; Hasenstein, Karl H

    2012-01-15

    Phosphorus (P) is a structural component of nucleic acids and phospholipids and plays important roles in plant growth and development. P accumulation was significantly reduced (about 35%) in rice leaves from plants grown under low (32 μM) P compared to 320 μM P grown plants. Genome response to low P was examined using the rice 60K oligonucleotide DNA microarrays. At the threshold significance of |log₂| fold>2.0, 21,033 genes (about 33.7% of all genes on the microarray) were affected by P deficiency. Among all genes on the microarray, 4271 genes were sorted into 51 metabolic pathways. Low P affected 1494 (35.0%) genes and the largest category of genes was related to sucrose degradation to ethanol and lactate pathway. To survey the role of P in rice, 25 pathways were selected based on number of affected genes. Among these pathways, cytosolic glycolysis contained the least number of upregulated but most down-regulated genes. Low P decreased glucose, pyruvate and chlorophyll, and genes related to carbon metabolism and chlorophyllide a biosynthesis. However, sucrose and starch levels increased. These results indicate that P nutrition affects diverse metabolic pathways mostly related to glucose, pyruvate, sucrose, starch, and chlorophyll a. PMID:21978493

  8. Oil production from Yarrowia lipolytica Po1g using rice bran hydrolysate.

    PubMed

    Tsigie, Yeshitila Asteraye; Wang, Chun-Yuan; Kasim, Novy S; Diem, Quy-Do; Huynh, Lien-Huong; Ho, Quoc-Phong; Truong, Chi-Thanh; Ju, Yi-Hsu

    2012-01-01

    The purpose of this study was to produce microbial oil from Yarrowia lipolytica Po1g grown in defatted rice bran hydrolysate. After removing oil from rice bran by Soxhlet extraction, the bran is subjected to acid hydrolysis with various sulfuric acid concentrations (1-4% v/v), reaction times (1-8 h), and reaction temperatures (60-120°C). The optimal conditions for maximum total sugar production from the hydrolysate were found to be 3% sulfuric acid at 90°C for 6 h. Glucose was the predominant sugar (43.20 ± 0.28 g/L) followed by xylose (4.93 ± 0.03 g/L) and arabinose (2.09 ± 0.01 g/L). The hydrolysate was subsequently detoxified by neutralization to reduce the amount of inhibitors such as 5-hydroxymethylfurfural (HMF) and furfural to increase its potential as a medium for culturing Y. lipolytica Po1g. Dry cell mass and lipid content of Y. lipolytica Po1g grown in detoxified defatted rice bran hydrolysate (DRBH) under optimum conditions were 10.75 g/L and 48.02%, respectively. PMID:22496604

  9. PIXE analyses of cesium in rice grains

    NASA Astrophysics Data System (ADS)

    Sugai, Hiroyuki; Ishii, Keizo; Matsuyama, Shigeo; Terakawa, Atsuki; Kikuchi, Yohei; Takahashi, Hiroaki; Ishizaki, Azusa; Fujishiro, Fumito; Arai, Hirotsugu; Osada, Naoyuki; Karahashi, Masahiro; Nozawa, Yuichiro; Yamauchi, Shosei; Kikuchi, Kosuke; Koshio, Shigeki; Watanabe, Koji

    2014-01-01

    The Fukushima nuclear power plant accident released vast amounts of radioactive material into the environment. For instance, 134Cs and 137Cs have half-lives of about 2 and 30 years, respectively, and emit many harmful gamma rays. In 2012, rice with radioactivity >100 Bq/kg was occasionally reported in Fukushima prefecture. To determine where and how cesium accumulates in rice, we grew rice in soil containing stable cesium and investigated the distribution of cesium in rice using particle-induced X-ray emission (PIXE). This study found that cesium is accumulated in bran and germ at high concentrations, and white rice contains 40% of the cesium found in brown rice.

  10. Gene transfer rate from CL rice to diverse red rice biotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The future and sustainability of ClearfieldTM (CL) technology at the producers’ level will be dictated by various factors. Among many, prominent factors which affect the transfer of ALS-resistant gene from CL rice to red rice are: disparity in red rice biotypes and CL cultivars; flowering time of re...

  11. Screening and association mapping of rice blast disease resistance using a diverse collection of rice germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast, caused by the fungus Magnaporthe oryzae B. Couch, is a very serious disease in rice (Oryza sativa L.) worldwide. Incorporation of new blast resistance genes into breeding lines is an important objective of many rice breeding programs. A diverse collection of 409 O. sativa accessions des...

  12. Influence of Water to Rice Ratio on Cooked Rice Flavor and Texture.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water to rice ratio is known to affect cooked rice texture, whereas, the effects on flavor are largely unknown. To determine the impact of the amount of water during cooking on flavor and texture descriptive attributes, three- water to rice ratios consisting of low (less than ideal), medium (ideal)...

  13. Factors affecting the outcrossing rate between Clearfield rice and red rice (Oryza sativa)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The commercialization of imazethapyr-resistant (Clearfield[TM], CL) rice in the southern United States has raised serious concerns about gene flow to red rice, producing imazethapyr-resistant red rice populations. Our objectives were to determine the impact of planting date, CL cultivars, and red ri...

  14. Relative competitive ability of rice with strawhull and blackhull red rice biotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed interference depends largely upon the species composition of the weed community and an ability to compete with the cultured crop. Weedy red rice is a major weed pest of rice in the southern U.S. The focus of this study was to evaluate the competitive ability of rice against common, genetically ...

  15. High-throughput measurement of rice tillers using a conveyor equipped with x-ray computed tomography

    NASA Astrophysics Data System (ADS)

    Yang, Wanneng; Xu, Xiaochun; Duan, Lingfeng; Luo, Qingming; Chen, Shangbin; Zeng, Shaoqun; Liu, Qian

    2011-02-01

    Tillering is one of the most important agronomic traits because the number of shoots per plant determines panicle number, a key component of grain yield. The conventional method of counting tillers is still manual. Under the condition of mass measurement, the accuracy and efficiency could be gradually degraded along with fatigue of experienced staff. Thus, manual measurement, including counting and recording, is not only time consuming but also lack objectivity. To automate this process, we developed a high-throughput facility, dubbed high-throughput system for measuring automatically rice tillers (H-SMART), for measuring rice tillers based on a conventional x-ray computed tomography (CT) system and industrial conveyor. Each pot-grown rice plant was delivered into the CT system for scanning via the conveyor equipment. A filtered back-projection algorithm was used to reconstruct the transverse section image of the rice culms. The number of tillers was then automatically extracted by image segmentation. To evaluate the accuracy of this system, three batches of rice at different growth stages (tillering, heading, or filling) were tested, yielding absolute mean absolute errors of 0.22, 0.36, and 0.36, respectively. Subsequently, the complete machine was used under industry conditions to estimate its efficiency, which was 4320 pots per continuous 24 h workday. Thus, the H-SMART could determine the number of tillers of pot-grown rice plants, providing three advantages over the manual tillering method: absence of human disturbance, automation, and high throughput. This facility expands the application of agricultural photonics in plant phenomics.

  16. Expression of Zinc Transporter Genes in Rice as Influenced by Zinc-Solubilizing Enterobacter cloacae Strain ZSB14.

    PubMed

    Krithika, Selvaraj; Balachandar, Dananjeyan

    2016-01-01

    Zinc (Zn) deficiency in major food crops has been considered as an important factor affecting the crop production and subsequently the human health. Rice (Oryza sativa) is sensitive to Zn deficiency and thereby causes malnutrition to most of the rice-eating Asian populations. Application of zinc solubilizing bacteria (ZSB) could be a sustainable agronomic approach to increase the soil available Zn which can mitigate the yield loss and consequently the nutritional quality of rice. Understanding the molecular interactions between rice and unexplored ZSB is useful for overcoming Zn deficiency problems. In the present study, the role of zinc solubilizing bacterial strain Enterobacter cloacae strain ZSB14 on regulation of Zn-regulated transporters and iron (Fe)-regulated transporter-like protein (ZIP) genes in rice under iron sufficient and deficient conditions was assessed by quantitative real-time reverse transcription PCR. The expression patterns of OsZIP1, OsZIP4, and OsZIP5 in root and shoot of rice were altered due to the Zn availability as dictated by Zn sources and ZSB inoculation. Fe sufficiency significantly reduced the root and shoot OsZIP1 expression, but not the OsZIP4 and OsZIP5 levels. Zinc oxide in the growth medium up-regulated all the assessed ZIP genes in root and shoot of rice seedlings. When ZSB was inoculated to rice seedlings grown with insoluble zinc oxide in the growth medium, the expression of root and shoot OsZIP1, OsZIP4, and OsZIP5 was reduced. In the absence of zinc oxide, ZSB inoculation up-regulated OsZIP1 and OsZIP5 expressions. Zinc nutrition provided to the rice seedling through ZSB-bound zinc oxide solubilization was comparable to the soluble zinc sulfate application which was evident through the ZIP genes' expression and the Zn accumulation in root and shoot of rice seedlings. These results demonstrate that ZSB could play a crucial role in zinc fertilization and fortification of rice. PMID:27092162

  17. Expression of Zinc Transporter Genes in Rice as Influenced by Zinc-Solubilizing Enterobacter cloacae Strain ZSB14

    PubMed Central

    Krithika, Selvaraj; Balachandar, Dananjeyan

    2016-01-01

    Zinc (Zn) deficiency in major food crops has been considered as an important factor affecting the crop production and subsequently the human health. Rice (Oryza sativa) is sensitive to Zn deficiency and thereby causes malnutrition to most of the rice-eating Asian populations. Application of zinc solubilizing bacteria (ZSB) could be a sustainable agronomic approach to increase the soil available Zn which can mitigate the yield loss and consequently the nutritional quality of rice. Understanding the molecular interactions between rice and unexplored ZSB is useful for overcoming Zn deficiency problems. In the present study, the role of zinc solubilizing bacterial strain Enterobacter cloacae strain ZSB14 on regulation of Zn-regulated transporters and iron (Fe)-regulated transporter-like protein (ZIP) genes in rice under iron sufficient and deficient conditions was assessed by quantitative real-time reverse transcription PCR. The expression patterns of OsZIP1, OsZIP4, and OsZIP5 in root and shoot of rice were altered due to the Zn availability as dictated by Zn sources and ZSB inoculation. Fe sufficiency significantly reduced the root and shoot OsZIP1 expression, but not the OsZIP4 and OsZIP5 levels. Zinc oxide in the growth medium up-regulated all the assessed ZIP genes in root and shoot of rice seedlings. When ZSB was inoculated to rice seedlings grown with insoluble zinc oxide in the growth medium, the expression of root and shoot OsZIP1, OsZIP4, and OsZIP5 was reduced. In the absence of zinc oxide, ZSB inoculation up-regulated OsZIP1 and OsZIP5 expressions. Zinc nutrition provided to the rice seedling through ZSB-bound zinc oxide solubilization was comparable to the soluble zinc sulfate application which was evident through the ZIP genes’ expression and the Zn accumulation in root and shoot of rice seedlings. These results demonstrate that ZSB could play a crucial role in zinc fertilization and fortification of rice. PMID:27092162

  18. Eliminating aluminum toxicity in an acid sulfate soil for rice cultivation using plant growth promoting bacteria.

    PubMed

    Panhwar, Qurban Ali; Naher, Umme Aminun; Radziah, Othman; Shamshuddin, Jusop; Razi, Ismail Mohd

    2015-01-01

    Aluminum toxicity is widely considered as the most important limiting factor for plants growing in acid sulfate soils. A study was conducted in laboratory and in field to ameliorate Al toxicity using plant growth promoting bacteria (PGPB), ground magnesium limestone (GML) and ground basalt. Five-day-old rice seedlings were inoculated by Bacillus sp., Stenotrophomonas maltophila, Burkholderia thailandensis and Burkholderia seminalis and grown for 21 days in Hoagland solution (pH 4.0) at various Al concentrations (0, 50 and 100 μM). Toxicity symptoms in root and leaf were studied using scanning electron microscope. In the field, biofertilizer (PGPB), GML and basalt were applied (4 t·ha-1 each). Results showed that Al severely affected the growth of rice. At high concentrations, the root surface was ruptured, leading to cell collapse; however, no damages were observed in the PGPB inoculated seedlings. After 21 days of inoculation, solution pH increased to >6.0, while the control treatment remained same. Field study showed that the highest rice growth and yield were obtained in the bio-fertilizer and GML treatments. This study showed that Al toxicity was reduced by PGPB via production of organic acids that were able to chelate the Al and the production of polysaccharides that increased solution pH. The release of phytohormones further enhanced rice growth that resulted in yield increase. PMID:25710843

  19. Salt overly sensitive pathway members are influenced by diurnal rhythm in rice.

    PubMed

    Soni, Praveen; Kumar, Gautam; Soda, Neelam; Singla-Pareek, Sneh L; Pareek, Ashwani

    2013-07-01

    The diurnal rhythm controls many aspects of plant physiology such as flowering, photosynthesis and growth. Rice is one of the staple foods for world's population. Abiotic stresses such as salinity, drought, heat and cold severely affect rice production. Under salinity stress, maintenance of ion homeostasis is a major challenge, which also defines the tolerance level of a given genotype. Salt overly sensitive (SOS) pathway is well documented to play a key role in maintaining the Na(+) homeostasis in plant cell. However, it is not reported yet whether the transcriptional regulation of genes of this pathway are influenced by diurnal rhythm. In the present work, we have studied the diurnal pattern of transcript abundance of SOS pathway genes in rice at seedling stage.To rule out the effect of temperature fluctuations on the expression patterns of these genes, the seedlings were grown under constant temperature. We found that OsSOS3 and OsSOS2 exhibited a rhythmic and diurnal expression pattern, while OsSOS1did not have any specific pattern of expression. This analysis establishes a cross-link between diurnal rhythm and SOS pathway and suggests that SOS pathway is influenced by diurnal rhythm in rice. PMID:23656875

  20. Sprinkler irrigation of rice fields reduces grain arsenic but enhances cadmium.

    PubMed

    Moreno-Jiménez, Eduardo; Meharg, Andrew A; Smolders, Erik; Manzano, Rebeca; Becerra, Daniel; Sánchez-Llerena, Javier; Albarrán, Ángel; López-Piñero, Antonio

    2014-07-01

    Previous studies have demonstrated that rice cultivated under flooded conditions has higher concentrations of arsenic (As) but lower cadmium (Cd) compared to rice grown in unsaturated soils. To validate such effects over long terms under Mediterranean conditions a field experiment, conducted over 7 successive years was established in SW Spain. The impact of water management on rice production and grain arsenic (As) and cadmium (Cd) was measured, and As speciation was determined to inform toxicity evaluation. Sprinkler irrigation was compared to traditional flooding. Both irrigation techniques resulted in similar grain yields (~3000 kg grain ha(-1)). Successive sprinkler irrigation over 7 years decreased grain total As to one-sixth its initial concentration in the flooded system (0.55 to 0.09 mg As kg(-1)), while one cycle of sprinkler irrigation also reduced grain total As by one-third (0.20 mg kg(-1)). Grain inorganic As concentration increased up to 2 folds under flooded conditions compared to sprinkler irrigated fields while organic As was also lower in sprinkler system treatments, but to a lesser extent. This suggests that methylation is favored under water logging. However, sprinkler irrigation increased Cd transfer to grain by a factor of 10, reaching 0.05 mg Cd kg(-1) in 7 years. Sprinkler systems in paddy fields seem particularly suited for Mediterranean climates and are able to mitigate against excessive As accumulation, but our evidence shows that an increased Cd load in rice grain may result. PMID:24742557

  1. C4 Photosynthesis in the Rice Paddy: Insights from the Noxious Weed Echinochloa glabrescens1[OPEN

    PubMed Central

    Covshoff, Sarah; Szecowka, Marek; Hughes, Thomas E.; Kelly, Steven; Bailey, Karen J.; Sage, Tammy L.; Pachebat, Justin A.; Leegood, Richard

    2016-01-01

    The C4 pathway is a highly complex trait that increases photosynthetic efficiency in more than 60 plant lineages. Although the majority of C4 plants occupy disturbed, arid, and nutrient-poor habitats, some grow in high-nutrient, waterlogged conditions. One such example is Echinochloa glabrescens, which is an aggressive weed of rice paddies. We generated comprehensive transcriptome datasets for C4 E. glabrescens and C3 rice to identify genes associated with adaption to waterlogged, nutrient-replete conditions, but also used the data to better understand how C4 photosynthesis operates in these conditions. Leaves of E. glabrescens exhibited classical Kranz anatomy with lightly lobed mesophyll cells having low chloroplast coverage. As with rice and other hygrophytic C3 species, leaves of E. glabrescens accumulated a chloroplastic phosphoenolpyruvate carboxylase protein, albeit at reduced amounts relative to rice. The arid-grown species Setaria italica (C4) and Brachypodium distachyon (C3) were also found to accumulate chloroplastic phosphoenolpyruvate carboxylase. We identified a molecular signature associated with C4 photosynthesis in nutrient-replete, waterlogged conditions that is highly similar to those previously reported from C4 plants that grow in more arid conditions. We also identified a cohort of genes that have been subjected to a selective sweep associated with growth in paddy conditions. Overall, this approach highlights the value of using wild species such as weeds to identify adaptions to specific conditions associated with high-yielding crops in agriculture. PMID:26527656

  2. ACC deaminase and IAA producing growth promoting bacteria from the rhizosphere soil of tropical rice plants.

    PubMed

    Bal, Himadri Bhusan; Das, Subhasis; Dangar, Tushar K; Adhya, Tapan K

    2013-12-01

    Beneficial plant-associated bacteria play a key role in supporting and/or promoting plant growth and health. Plant growth promoting bacteria present in the rhizosphere of crop plants can directly affect plant metabolism or modulate phytohormone production or degradation. We isolated 355 bacteria from the rhizosphere of rice plants grown in the farmers' fields in the coastal rice field soil from five different locations of the Ganjam district of Odisha, India. Six bacteria producing both ACC deaminase (ranging from 603.94 to 1350.02 nmol α-ketobutyrate mg(-1)  h(-1) ) and indole acetic acid (IAA; ranging from 10.54 to 37.65 μM ml(-1) ) in pure cultures were further identified using polyphasic taxonomy including BIOLOG((R)) , FAME analysis and the 16S rRNA gene sequencing. Phylogenetic analyses of the isolates resulted into five major clusters to include members of the genera Bacillus, Microbacterium, Methylophaga, Agromyces, and Paenibacillus. Seed inoculation of rice (cv. Naveen) by the six individual PGPR isolates had a considerable impact on different growth parameters including root elongation that was positively correlated with ACC deaminase activity and IAA production. The cultures also had other plant growth attributes including ammonia production and at least two isolates produced siderophores. Study indicates that presence of diverse rhizobacteria with effective growth-promoting traits, in the rice rhizosphere, may be exploited for a sustainable crop management under field conditions. PMID:23681643

  3. Identification of drought-responsive genes in roots of upland rice (Oryza sativa L)

    PubMed Central

    Rabello, Aline R; Guimarães, Cléber M; Rangel, Paulo HN; da Silva, Felipe R; Seixas, Daniela; de Souza, Emanuel; Brasileiro, Ana CM; Spehar, Carlos R; Ferreira, Márcio E; Mehta, Ângela

    2008-01-01

    Background Rice (Oryza sativa L.) germplasm represents an extraordinary source of genes that control traits of agronomic importance such as drought tolerance. This diversity is the basis for the development of new cultivars better adapted to water restriction conditions, in particular for upland rice, which is grown under rainfall. The analyses of subtractive cDNA libraries and differential protein expression of drought tolerant and susceptible genotypes can contribute to the understanding of the genetic control of water use efficiency in rice. Results Two subtractive libraries were constructed using cDNA of drought susceptible and tolerant genotypes submitted to stress against cDNA of well-watered plants. In silico analysis revealed 463 reads, which were grouped into 282 clusters. Several genes expressed exclusively in the tolerant or susceptible genotypes were identified. Additionally, proteome analysis of roots from stressed plants was performed and 22 proteins putatively associated to drought tolerance were identified by mass spectrometry. Conclusion Several genes and proteins involved in drought-response, as well as genes with no described homologs were identified. Genes exclusively expressed in the tolerant genotype were, in general, related to maintenance of turgor and cell integrity. In contrast, in the susceptible genotype, expression of genes involved in protection against cell damage was not detected. Several protein families identified in the proteomic analysis were not detected in the cDNA analysis. There is an indication that the mechanisms of susceptibility to drought in upland rice are similar to those of lowland varieties. PMID:18922162

  4. Gravitropism of maize and rice coleoptiles: dependence on the stimulation angle.

    PubMed

    Iino, M; Tarui, Y; Uematsu, C

    1996-10-01

    Gravitropism of maize and rice coleoptiles was investigated with respect to its dependence on the angle of displacement or the initial stimulation angle (ISA). Close examination of curvature kinetics and the response to a drop in stimulation angle (SA) indicated that the gravtropic response during an early but substantial part of the curvature development is directly related to the ISA, there being no effect of the reduction of SA resulting from the curvature response itself. On the basis of this finding, the relationship between the steady SA and the curvature rate was determined. In maize, the curvature rate increased linearly with the sines of SAs up to an SA of 90 degrees. Rice coleoptiles, however, showed a saturation curve in the same range of SAs. The saturation profile was nearly identical between coleoptiles grown in air and those submerged in water, although the latter elongated much faster. Rice coleoptiles appeared to be far more sensitive to gravity than maize coleoptiles. It is concluded that the sensitivity to gravity, assessed through dependence on ISA, is a property inherent to a given gravitropic organ. Long-term measurements of curvature indicated that the coleoptiles bend back past the vertical. This overshooting was marked in submerged rice coleoptiles. PMID:11539324

  5. Foliar application with nano-silicon alleviates Cd toxicity in rice seedlings.

    PubMed

    Wang, Shihua; Wang, Fayuan; Gao, Shuangcheng

    2015-02-01

    Nanofertilizers may be more effective than regular fertilizers in improving plant nutrition, enhancing nutrition use efficiency, and protecting plants from environmental stress. A hydroponic pot experiment was conducted to study the role of foliar application with 2.5 mM nano-silicon in alleviating Cd stress in rice seedlings (Oryza sativa L. cv Youyou 128) grown in solution added with or without 20 μM CdCl2. The results showed that Cd treatment decreased the growth and the contents of Mg, Fe, Zn, chlorophyll a, and glutathione (GSH), accompanied by a significant increase in Cd accumulation. However, foliar application with nano-Si improved the growth, Mg, Fe, and Zn nutrition, and the contents of chlorophyll a of the rice seedlings under Cd stress and decreased Cd accumulation and translocation of Cd from root to shoot. Cd treatment produced oxidative stress to rice seedlings indicated by a higher lipid peroxidation level (as malondialdehyde (MDA)) and higher activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and a lower GSH content. However, those nano-Si-treated plants had lower MDA but higher GSH content and different antioxidant enzyme activities, indicating a higher Cd tolerance in them. The results suggested that nano-Si application alleviated Cd toxicity in rice by decreasing Cd accumulation, Cd partitioning in shoot and MDA level and by increasing content of some mineral elements (Mg, Fe, and Zn) and antioxidant capacity. PMID:25217281

  6. Domestication history and geographical adaptation inferred from a SNP map of African rice.

    PubMed

    Meyer, Rachel S; Choi, Jae Young; Sanches, Michelle; Plessis, Anne; Flowers, Jonathan M; Amas, Junrey; Dorph, Katherine; Barretto, Annie; Gross, Briana; Fuller, Dorian Q; Bimpong, Isaac Kofi; Ndjiondjop, Marie-Noelle; Hazzouri, Khaled M; Gregorio, Glenn B; Purugganan, Michael D

    2016-09-01

    African rice (Oryza glaberrima Steud.) is a cereal crop species closely related to Asian rice (Oryza sativa L.) but was independently domesticated in West Africa ∼3,000 years ago. African rice is rarely grown outside sub-Saharan Africa but is of global interest because of its tolerance to abiotic stresses. Here we describe a map of 2.32 million SNPs of African rice from whole-genome resequencing of 93 landraces. Population genomic analysis shows a population bottleneck in this species that began ∼13,000-15,000 years ago with effective population size reaching its minimum value ∼3,500 years ago, suggesting a protracted period of population size reduction likely commencing with predomestication management and/or cultivation. Genome-wide association studies (GWAS) for six salt tolerance traits identify 11 significant loci, 4 of which are within ∼300 kb of genomic regions that possess signatures of positive selection, suggesting adaptive geographical divergence for salt tolerance in this species. PMID:27500524

  7. Measuring evapotranspiration and carbon dioxide fluxes in Mid-South US rice (Oryza Sativa) with eddy covariance

    NASA Astrophysics Data System (ADS)

    Fong, B.; Reba, M. L.

    2015-12-01

    Rice (Oryza sativa), a staple crop for a large portion of the Earth's population, is grown under flooded soil conditions. This results in greater water use than most other agricultural crops. Nearly 75% of US rice is grown the Mid-South states of the US. The objective of this study is to measure the evapotranspiration (ET) and carbon dioxide flux of conventionally flooded, commercial sized rice fields in this region. Measurements were made throughout the entire growing season during 2012, 2013, and 2014. The mean daily uptake of CO2 emissions under flooded soil conditions was at 4.0 g m-2 day-1, four times greater during flood than post flood, while ET was measured during flood at 3.12 mm day-1 was two times greater than post flood. Entire season measurements are important to characterize the micrometeorological conditions over agriculture fields. Future work will use eddy covariance to compare alternate irrigation methods on the net ecosystem exchange in commercial sized rice fields.

  8. Wheat products as acceptable substitutes for rice.

    PubMed

    Yu, B H; Kies, C

    1993-07-01

    The objective of the study was to compare the acceptability to semi-trained US American and Asian palatability panelist, of four wheat products processed to be possible replacers of rice in human diets. Products evaluated using rice as the control standard of excellence were steamed whole wheat, couscous (steamed, extracted wheat flour semolina), rosamarina (rice shaped, extracted wheat flour pasta), and bulgar (steamed, pre-cooked partly debranned, cracked wheat). Using a ten point hedonic rating scale, both groups of panelists gave rosamarina closely followed by couscous, most favorable ratings although these ratings were somewhat lower than that of the positive control, steamed polished rice. Bulgar wheat was given the lowest evaluation and was, in general, found to be an unacceptable replacement for rice by both American and Asian judges because of its dark, 'greasy' color and distinctive flavor. In their personal dietaries, judges included rice from 0.25 to 18 times per week with the Asian judges consuming rice significantly more times per week than did the American judges (10.8 +/- 4.71 vs 1.75 +/- 1.65, p < 0.01). However, rice consumption patterns, nationality, race, or sex of the judges was not demonstrated to affect scoring of the wheat products as rice replacers. PMID:8332588

  9. Bioethanol production from rice straw residues.

    PubMed

    Belal, Elsayed B

    2013-01-01

    A rice straw - cellulose utilizing mold was isolated from rotted rice straw residues. The efficient rice straw degrading microorganism was identified as Trichoderma reesei. The results showed that different carbon sources in liquid culture such as rice straw, carboxymethyl cellulose, filter paper, sugar cane bagasse, cotton stalk and banana stalk induced T. reesei cellulase production whereas glucose or Potato Dextrose repressed the synthesis of cellulase. T. reesei cellulase was produced by the solid state culture on rice straw medium. The optimal pH and temperature for T. reesei cellulase production were 6 and 25 °C, respectively. Rice straw exhibited different susceptibilities towards cellulase to their conversion to reducing sugars. The present study showed also that, the general trend of rice straw bioconversion with cellulase was more than the general trend by T. reesei. This enzyme effectively led to enzymatic conversion of acid, alkali and ultrasonic pretreated cellulose from rice straw into glucose, followed by fermentation into ethanol. The combined method of acid pretreatment with ultrasound and subsequent enzyme treatment resulted the highest conversion of lignocellulose in rice straw to sugar and consequently, highest ethanol concentration after 7 days fermentation with S. cerevisae yeast. The ethanol yield in this study was about 10 and 11 g.L(-1). PMID:24159309

  10. Bioethanol production from rice straw residues

    PubMed Central

    Belal, Elsayed B.

    2013-01-01

    A rice straw - cellulose utilizing mold was isolated from rotted rice straw residues. The efficient rice straw degrading microorganism was identified as Trichoderma reesei. The results showed that different carbon sources in liquid culture such as rice straw, carboxymethyl cellulose, filter paper, sugar cane bagasse, cotton stalk and banana stalk induced T. reesei cellulase production whereas glucose or Potato Dextrose repressed the synthesis of cellulase. T. reesei cellulase was produced by the solid state culture on rice straw medium. The optimal pH and temperature for T. reesei cellulase production were 6 and 25 °C, respectively. Rice straw exhibited different susceptibilities towards cellulase to their conversion to reducing sugars. The present study showed also that, the general trend of rice straw bioconversion with cellulase was more than the general trend by T. reesei. This enzyme effectively led to enzymatic conversion of acid, alkali and ultrasonic pretreated cellulose from rice straw into glucose, followed by fermentation into ethanol. The combined method of acid pretreatment with ultrasound and subsequent enzyme treatment resulted the highest conversion of lignocellulose in rice straw to sugar and consequently, highest ethanol concentration after 7 days fermentation with S. cerevisae yeast. The ethanol yield in this study was about 10 and 11 g.L−1. PMID:24159309

  11. Information Commons for Rice (IC4R).

    PubMed

    Hao, Lili; Zhang, Huiyong; Zhang, Zhang; Hu, Songnian; Xue, Yu

    2016-01-01

    Rice is the most important staple food for a large part of the world's human population and also a key model organism for plant research. Here, we present Information Commons for Rice (IC4R; http://ic4r.org), a rice knowledgebase featuring adoption of an extensible and sustainable architecture that integrates multiple omics data through community-contributed modules. Each module is developed and maintained by different committed groups, deals with data collection, processing and visualization, and delivers data on-demand via web services. In the current version, IC4R incorporates a variety of rice data through multiple committed modules, including genome-wide expression profiles derived entirely from RNA-Seq data, resequencing-based genomic variations obtained from re-sequencing data of thousands of rice varieties, plant homologous genes covering multiple diverse plant species, post-translational modifications, rice-related literatures and gene annotations contributed by the rice research community. Unlike extant related databases, IC4R is designed for scalability and sustainability and thus also features collaborative integration of rice data and low costs for database update and maintenance. Future directions of IC4R include incorporation of other omics data and association of multiple omics data with agronomically important traits, dedicating to build IC4R into a valuable knowledgebase for both basic and translational researches in rice. PMID:26519466

  12. Information Commons for Rice (IC4R)

    PubMed Central

    2016-01-01

    Rice is the most important staple food for a large part of the world's human population and also a key model organism for plant research. Here, we present Information Commons for Rice (IC4R; http://ic4r.org), a rice knowledgebase featuring adoption of an extensible and sustainable architecture that integrates multiple omics data through community-contributed modules. Each module is developed and maintained by different committed groups, deals with data collection, processing and visualization, and delivers data on-demand via web services. In the current version, IC4R incorporates a variety of rice data through multiple committed modules, including genome-wide expression profiles derived entirely from RNA-Seq data, resequencing-based genomic variations obtained from re-sequencing data of thousands of rice varieties, plant homologous genes covering multiple diverse plant species, post-translational modifications, rice-related literatures and gene annotations contributed by the rice research community. Unlike extant related databases, IC4R is designed for scalability and sustainability and thus also features collaborative integration of rice data and low costs for database update and maintenance. Future directions of IC4R include incorporation of other omics data and association of multiple omics data with agronomically important traits, dedicating to build IC4R into a valuable knowledgebase for both basic and translational researches in rice. PMID:26519466

  13. Respiratory health of California rice farmers.

    PubMed

    McCurdy, S A; Ferguson, T J; Goldsmith, D F; Parker, J E; Schenker, M B

    1996-05-01

    Rice farmers are occupationally exposed to agents that may affect respiratory health, including inorganic dusts and smoke from burning of agricultural waste. To assess respiratory health of this occupational group, we conducted a cross-sectional study, including a self-administered health and work questionnaire, spirometry, and chest radiography among 464 male California rice farmers. Mean age +/- SD was 48.3 +/- 15.2 yr; mean duration of rice farming was 25.7 +/- 14.3 yr. Prevalences for respiratory symptoms were: chronic bronchitis (6.3%), physician-diagnosed asthma (7.1%), and persistent wheeze (8.8%). Chronic cough was reported by 7.1% of respondents and was associated with reported hours per year burning rice stubble. Mean FEV1 and FVC were at expected values. FEV1 was inversely associated with years working in rice storage and use of heated rice dryers. Mean FEF25-75 was 93% of expected and was inversely associated with rice storage activities involving unheated rice driers. ILO profusion scores > or = 1/0 for small irregular opacities were seen in 18 (10.1%) of 178 chest radiographs. Study findings suggest increased asthma prevalence among California rice farmers. Radiologic findings consistent with dust or fiber exposure were increased compared with those of the general population, although no associations with specific farming activities were identified. PMID:8630601

  14. Loss-of-function mutation of rice SLAC7 decreases chloroplast stability and induces a photoprotection mechanism in rice.

    PubMed

    Fan, Xiaolei; Wu, Jiemin; Chen, Taiyu; Tie, Weiwei; Chen, Hao; Zhou, Fei; Lin, Yongjun

    2015-12-01

    Plants absorb sunlight to power the photochemical reactions of photosynthesis, which can potentially damage the photosynthetic machinery. However, the mechanism that protects chloroplasts from the damage remains unclear. In this work, we demonstrated that rice (Oryza sativa L.) SLAC7 is a generally expressed membrane protein. Loss-of-function of SLAC7 caused continuous damage to the chloroplasts of mutant leaves under normal light conditions. Ion leakage indicators related to leaf damage such as H2 O2 and abscisic acid levels were significantly higher in slac7-1 than in the wild type. Consistently, the photosynthesis efficiency and Fv/Fm ratio of slac7-1 were significantly decreased (similar to photoinhibition). In response to chloroplast damage, slac7-1 altered its leaf morphology (curled or fused leaf) by the synergy between plant hormones and transcriptional factors to decrease the absorption of light, suggesting that a photoprotection mechanism for chloroplast damage was activated in slac7-1. When grown in dark conditions, slac7-1 displayed a normal phenotype. SLAC7 under the control of the AtSLAC1 promoter could partially complement the phenotypes of Arabidopsis slac1 mutants, indicating a partial conservation of SLAC protein functions. These results suggest that SLAC7 is essential for maintaining the chloroplast stability in rice. PMID:25739330

  15. Spectral reflectance of rice seedlings

    NASA Astrophysics Data System (ADS)

    Adams, Alois J.; Herden, Deborah

    1999-01-01

    The spectral reflectance of young rice plants was measured in the visible and near-IR region of the spectrum using a commercially available fiber optic contact probe and miniature spectrometer. This work aims to identify an empirical spectral index which changes when rice is exposed to increased levels of chloride anions in the irrigation water and soil. The ratio of near IR reflectance to that of green, R750/555 is known to be a quantitative measure of chlorophyll content in the leaf but int his study does not show a consistent shift for sample which are exposed to chloride levels equal to or less than 0.1 percent by mass of soil. However, leaf contact spectral reflectance measurements did reveal a significant and consistent increase in R750/555 along the length of the leaves, and this variation should represent an important factor in modeling remote and proximal sensing data.

  16. Rice, Japonica (Oryza sativa L.).

    PubMed

    Main, Marcy; Frame, Bronwyn; Wang, Kan

    2015-01-01

    The importance of rice, as a food crop, is reflected in the extensive global research being conducted in an effort to improve and better understand this particular agronomic plant. In regard to biotechnology, this has led to the development of numerous genetic transformation protocols. Over the years, many of these methods have become increasingly straightforward, rapid, and efficient, thereby making rice valuable as a model crop for scientific research and functional genomics. The focus of this chapter is on one such protocol that uses Agrobacterium-mediated transformation of Oryza sativa L. ssp. Japonica cv. Nipponbare with an emphasis on tissue desiccation. The explants consist of callus derived from mature seeds which are cocultivated on filter paper postinfection. Hygromycin selection is used for the recovery of subsequent genetically engineered events. PMID:25300839

  17. [Extraction and purification method of rice DNA from rice powder containing Konjak flour].

    PubMed

    Minematsu, Kazuhiko; Nakamura, Kosuke; Akiyama, Hiroshi; Harikai, Naoki; Nakajima, Osamu; Kitta, Kazumi; Teshima, Reiko; Iizuka, Tayoshi

    2010-01-01

    Rice powder containing Konjak flour made with tuberous roots of Amorphophallus konjac is imported as a rice-processed product from China to Japan. An improved DNA purification method for the polymerase chain reaction (PCR) analysis of rice in such products is necessary, since Konjak flour constituents absorb the DNA purification buffer to form a gel, and cause problems in the subsequent purification steps. Here, we present a simple preparative system for isolation of the rice and a purification method of the rice DNA from the product. The purified DNA was confirmed to be a good template for both PCR and real-time PCR. PMID:21071909

  18. Changes in CH4 emission from rice fields from 1960 to 1990s. 1. Impacts of modern rice technology

    NASA Astrophysics Data System (ADS)

    van der Gon, Hugo Denier

    2000-03-01

    Four countries (Indonesia, Philippines, Thailand, and Nepal) were taken as an example to assess the impact of changes in rice cultivation on methane emissions from rice fields since the 1960s. The change of rice area by type of culture from 1960-1990s is estimated, and its relative contribution to national harvested rice area is calculated and multiplied with an emission factor, to derive the relative methane emission per unit rice land. Relative methane emission per ha rice land has increased since 1960 for all four countries, largely due to an increase in irrigated rice area and partly due to a decrease in upland rice area. Patterns of rice area changes and related emission changes differ considerably among countries. On the basis of the rice area increases between 1960 and the 1990s, significant increases in methane emissions from rice fields due to increases in total rice cultivated area are not to be expected in the future. The impact of modern rice variety adoption is assessed by relating methane emissions to rice production. The organic matter returned to the paddy soil is largely determined by rice biomass production which, given a certain yield, is different for traditional and modern rice varieties. By calculating total organic matter returned to rice paddy soils and assuming a constant fraction to be emitted as methane, rice production and methane emission can be related. The analysis indicates that (1) up to now, rice yield increases in countries with high modern rice variety adoption have not resulted in increased methane emissions per unit of harvested area and, (2) global annual emission from rice fields may be considerably lower than generally assumed. The introduction of modern rice varieties can be regarded as a historical methane emission mitigation strategy because higher rice yields resulted in lower or equal methane emissions.

  19. Changes in CH4 emission from rice fields from 1960 to 1990s: 1. Impacts of modern rice technology

    NASA Astrophysics Data System (ADS)

    Gon, Hugo Denier

    2000-03-01

    Four countries (Indonesia, Philippines, Thailand, and Nepal) were taken as an example to assess the impact of changes in rice cultivation on methane emissions from rice fields since the 1960s. The change of rice area by type of culture from 1960-1990s is estimated, and its relative contribution to national harvested rice area is calculated and multiplied with an emission factor, to derive the relative methane emission per unit rice land. Relative methane emission per ha rice land has increased since 1960 for all four countries, largely due to an increase in irrigated rice area and partly due to a decrease in upland rice area. Patterns of rice area changes and related emission changes differ considerably among countries. On the basis of the rice area increases between 1960 and the 1990s, significant increases in methane emissions from rice fields due to increases in total rice cultivated area are not to be expected in the future. The impact of modern rice variety adoption is assessed by relating methane emissions to rice production. The organic matter returned to the paddy soil is largely determined by rice biomass production which, given a certain yield, is different for traditional and modern rice varieties. By calculating total organic matter returned to rice paddy soils and assuming a constant fraction to be emitted as methane, rice production and methane emission can be related. The analysis indicates that (1) up to now, rice yield increases in countries with high modern rice variety adoption have not resulted in increased methane emissions per unit of harvested area and, (2) global annual emission from rice fields may be considerably lower than generally assumed. The introduction of modern rice varieties can be regarded as a historical methane emission mitigation strategy because higher rice yields resulted in lower or equal methane emissions.

  20. Silicon isotope fractionation between rice plants and nutrient solution and its significance to the study of the silicon cycle

    NASA Astrophysics Data System (ADS)

    Ding, T. P.; Tian, S. H.; Sun, L.; Wu, L. H.; Zhou, J. X.; Chen, Z. Y.

    2008-12-01

    The silicon isotope fractionation between rice plant and nutrient solution was studied experimentally. Rice plants were grown to maturity with the hydroponic culture in a naturally lit glasshouse. The nutrient solution was sampled for 14 times during the whole rice growth period. The rice plants were collected at various growth stages and different parts of the plants were sampled separately. The silica contents of the samples were determined by the gravimetric method and the silicon isotope compositions were measured using the SiF 4 method. In the growth process, the silicon content in the nutrient solution decreased gradually from 16 mM at starting stage to 0.1-0.2 mM at harvest and the amount of silica in single rice plant increased gradually from 0.00013 g at start to 4.329 g at harvest. Within rice plant the SiO 2 fraction in roots reduced continuously from 0.23 at the seedling stage, through 0.12 at the tiller stage, 0.05 at the jointing stage, 0.023 at the heading stage, to 0.009 at the maturity stage. Accordingly, the fraction of SiO 2 in aerial parts increased from 0.77, through 0.88, 0.95, 0.977, to 0.991 for the same stages. The silicon content in roots decreased from the jointing stage, through the heading stage, to the maturity stage, parallel to the decrease of silicon content in the nutrient solution. At the maturity stage, the silicon content increased from roots, through stem and leaves, to husks, but decreased drastically from husks to grains. These observations show that transpiration and evaporation may play an important role in silica transportation and precipitation within rice plants. It was observed that the δ30Si of the nutrient solution increased gradually from -0.1‰ at start to 1.5‰ at harvest, and the δ30Si of silicon absorbed by bulk rice plant increased gradually from -1.72‰ at start to -0.08‰ at harvest, reflecting the effect of the kinetic silicon isotope fractionation during silicon absorption by rice plants from nutrient

  1. Increased fitness of rice plants to abiotic stress via habitat adapted symbiosis: a strategy for mitigating impacts of climate change.

    PubMed

    Redman, Regina S; Kim, Yong Ok; Woodward, Claire J D A; Greer, Chris; Espino, Luis; Doty, Sharon L; Rodriguez, Rusty J

    2011-01-01

    Climate change and catastrophic events have contributed to rice shortages in several regions due to decreased water availability and soil salinization. Although not adapted to salt or drought stress, two commercial rice varieties achieved tolerance to these stresses by colonizing them with Class 2 fungal endophytes isolated from plants growing across moisture and salinity gradients.Plant growth and development, water usage, ROS sensitivity and osmolytes were measured with and without stress under controlled conditions.The endophytes conferred salt, drought and cold tolerance to growth chamber and greenhouse grown plants. Endophytes reduced water consumption by 20-30% and increased growth rate, reproductive yield, and biomass of greenhouse grown plants. In the absence of stress, there was no apparent cost of the endophytes to plants, however, endophyte colonization decreased from 100% at planting to 65% compared to greenhouse plants grown under continual stress (maintained 100% colonization).These findings indicate that rice plants can exhibit enhanced stress tolerance via symbiosis with Class 2 endophytes, and suggest that symbiotic technology may be useful in mitigating impacts of climate change on other crops and expanding agricultural production onto marginal lands. PMID:21750695

  2. Increased Fitness of Rice Plants to Abiotic Stress Via Habitat Adapted Symbiosis: A Strategy for Mitigating Impacts of Climate Change

    PubMed Central

    Redman, Regina S.; Kim, Yong Ok; Woodward, Claire J. D. A.; Greer, Chris; Espino, Luis; Doty, Sharon L.; Rodriguez, Rusty J.

    2011-01-01

    Climate change and catastrophic events have contributed to rice shortages in several regions due to decreased water availability and soil salinization. Although not adapted to salt or drought stress, two commercial rice varieties achieved tolerance to these stresses by colonizing them with Class 2 fungal endophytes isolated from plants growing across moisture and salinity gradients. Plant growth and development, water usage, ROS sensitivity and osmolytes were measured with and without stress under controlled conditions. The endophytes conferred salt, drought and cold tolerance to growth chamber and greenhouse grown plants. Endophytes reduced water consumption by 20–30% and increased growth rate, reproductive yield, and biomass of greenhouse grown plants. In the absence of stress, there was no apparent cost of the endophytes to plants, however, endophyte colonization decreased from 100% at planting to 65% compared to greenhouse plants grown under continual stress (maintained 100% colonization). These findings indicate that rice plants can exhibit enhanced stress tolerance via symbiosis with Class 2 endophytes, and suggest that symbiotic technology may be useful in mitigating impacts of climate change on other crops and expanding agricultural production onto marginal lands. PMID:21750695

  3. Increased fitness of rice plants to abiotic stress via habitat adapted symbiosis: A strategy for mitigating impacts of climate change

    USGS Publications Warehouse

    Redman, R.S.; Kim, Y.-O.; Woodward, C.J.D.A.; Greer, C.; Espino, L.; Doty, S.L.; Rodriguez, R.J.

    2011-01-01

    Climate change and catastrophic events have contributed to rice shortages in several regions due to decreased water availability and soil salinization. Although not adapted to salt or drought stress, two commercial rice varieties achieved tolerance to these stresses by colonizing them with Class 2 fungal endophytes isolated from plants growing across moisture and salinity gradients. Plant growth and development, water usage, ROS sensitivity and osmolytes were measured with and without stress under controlled conditions. The endophytes conferred salt, drought and cold tolerance to growth chamber and greenhouse grown plants. Endophytes reduced water consumption by 20–30% and increased growth rate, reproductive yield, and biomass of greenhouse grown plants. In the absence of stress, there was no apparent cost of the endophytes to plants, however, endophyte colonization decreased from 100% at planting to 65% compared to greenhouse plants grown under continual stress (maintained 100% colonization). These findings indicate that rice plants can exhibit enhanced stress tolerance via symbiosis with Class 2 endophytes, and suggest that symbiotic technology may be useful in mitigating impacts of climate change on other crops and expanding agricultural production onto marginal lands.

  4. Diversity of floral regulatory genes of japonica rice cultivated at northern latitudes

    PubMed Central

    2014-01-01

    Background Rice is considered a short day plant. Originally from tropical regions rice has been progressively adapted to temperate climates and long day conditions in part by modulating its sensitivity to day length. Heading date 3a (Hd3a) and RICE FLOWERING LOCUS T 1 (RFT1) that code for florigens, are known as major regulatory genes of floral transition in rice. Both Hd3a and RFT1 are regulated by Early heading date 1 (Ehd1) and Days to heading on chromosome 2 (DTH2) while Heading date 1 (Hd1) also governs Hd3a expression. To investigate the mechanism of rice adaptation to temperate climates we have analyzed the natural variation of these five genes in a collection of japonica rice representing the genetic diversity of long day cultivated rice. Results We have investigated polymorphisms of Hd3a, RFT1, Ehd1, Hd1 and DTH2 in a collection of 57 japonica varieties. Hd3a and RFT1 were highly conserved, displaying one major allele. Expression analysis suggested that RFT1 rather than Hd3a could be the pivotal gene controlling flowering under long day conditions. While few alleles were found in the Ehd1 promoter and DTH2 coding region, a high degree of variation in Hd1, including non-functional alleles, was observed. Correlation analysis between gene expression levels and flowering periods suggested the occurrence of other factors, additionally to Ehd1, affecting RFT1 regulation in long day adapted cultivars. Conclusions During domestication, rice expansion was accompanied by changes in the regulatory mechanism of flowering. The existence of non-functional Hd1 alleles and the lack of correlation of their presence with flowering times in plants grown under long day conditions, indicate a minor role of this branch in this process and the existence of an alternative regulatory pathway in northern latitudes. Expression analysis data and a high degree of conservation of RFT1 suggested that this gene could be the main factor regulating flowering among japonica cultivars

  5. Analysis of rice Act1 5' region activity in transgenic rice plants.

    PubMed Central

    Zhang, W; McElroy, D; Wu, R

    1991-01-01

    The 5' region of the rice actin 1 gene (Act1) has been developed as an efficient regulator of foreign gene expression in transgenic rice plants. To determine the pattern and level of rice Act1 5' region activity, transgenic rice plants containing the Act1 5' region fused to a bacterial beta-glucuronidase (Gus) coding sequence were generated. Two independent clonal lines of transgenic rice plants were analyzed in detail. Quantitative analysis showed that tissue from these transgenic rice plants have a level of GUS protein that represents as much as 3% of total soluble protein. We were able to demonstrate that Act1-Gus gene expression is constitutive throughout the sporophytic and gametophytic tissues of these transgenic rice plants. Plants from one transgenic line were analyzed for the segregation of GUS activity in pollen by in situ histochemical staining, and the inheritance and stability of Act1-Gus expression were assayed in subsequently derived progeny plants. PMID:1821763

  6. Rice genomes recorded ancient pararetrovirus activities: Virus genealogy and multiple origins of endogenization during rice speciation.

    PubMed

    Chen, Sunlu; Liu, Ruifang; Koyanagi, Kanako O; Kishima, Yuji

    2014-12-01

    Viral fossils in rice genomes are a best entity to understand ancient pararetrovirus activities through host plant history because of our advanced knowledge of the genomes and evolutionary history with rice and its related species. Here, we explored organization, geographic origins and genealogy of rice pararetroviruses, which were turned into endogenous rice tungro bacilliform virus-like (eRTBVL) sequences. About 300 eRTBVL sequences from three representative rice genomes were clearly classified into six families. Most of the endogenization events of the eRTBVLs were initiated before differentiation of the rice progenitor (> 160,000 years ago). We successfully followed the genealogy of old relic viruses during rice speciation, and inferred the geographical origins for these viruses. Possible virus genomic sequences were explained mostly by recombinations between different virus families. Interestingly, we discovered that only a few recombination events among the numerous occasions had determined the virus genealogy. PMID:25461539

  7. Calcium Supplementation Improves Na+/K+ Ratio, Antioxidant Defense and Glyoxalase Systems in Salt-Stressed Rice Seedlings

    PubMed Central

    Rahman, Anisur; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2016-01-01

    The present study investigates the regulatory role of exogenous calcium (Ca) in developing salt stress tolerance in rice seedlings. Hydroponically grown 13-day-old rice (Oryza sativa L. cv. BRRI dhan47) seedlings were exposed to 200 mM NaCl alone and combined with 2 mM CaCl2 and 2 mM ethylene glycol tetraacetic acid (EGTA, a Ca scavenger) for 3 days. The salt stress caused growth inhibition, chlorosis and water shortage in the rice seedlings. The salt-induced stress disrupted ion homeostasis through Na+ influx and K+ efflux, and decreased other mineral nutrient uptake. Salt stress caused oxidative stress in seedlings through lipid peroxidation, loss of plasma membrane integrity, higher reactive oxygen species (ROS) production and methylglyoxal (MG) formation. The salt-stressed seedlings supplemented with exogenous Ca recovered from water loss, chlorosis and growth inhibition. Calcium supplementation in the salt-stressed rice seedlings improved ion homeostasis by inhibition of Na+ influx and K+ leakage. Exogenous Ca also improved ROS and MG detoxification by improving the antioxidant defense and glyoxalase systems, respectively. On the other hand, applying EGTA along with salt and Ca again negatively affected the seedlings as EGTA negated Ca activity. It confirms that, the positive responses in salt-stressed rice seedlings to exogenous Ca were for Ca mediated improvement of ion homeostasis, antioxidant defense and glyoxalase system. PMID:27242816

  8. Effect of arsenite-oxidizing bacterium B. laterosporus on arsenite toxicity and arsenic translocation in rice seedlings.

    PubMed

    Yang, Gui-Di; Xie, Wan-Ying; Zhu, Xi; Huang, Yi; Yang, Xiao-Jun; Qiu, Zong-Qing; Lv, Zhen-Mao; Wang, Wen-Na; Lin, Wen-Xiong

    2015-10-01

    Arsenite [As (III)] oxidation can be accelerated by bacterial catalysis, but the effects of the accelerated oxidation on arsenic toxicity and translocation in rice plants are poorly understood. Herein we investigated how an arsenite-oxidizing bacterium, namely Brevibacillus laterosporus, influences As (III) toxicity and translocation in rice plants. Rice seedlings of four cultivars, namely Guangyou Ming 118 (GM), Teyou Hang II (TH), Shanyou 63 (SY) and Minghui 63 (MH), inoculated with or without the bacterium were grown hydroponically with As (III) to investigate its effects on arsenic toxicity and translocation in the plants. Percentages of As (III) oxidation in the solutions with the bacterium (100%) were all significantly higher than those without (30-72%). The addition of the bacterium significantly decreased As (III) concentrations in SY root, GM root and shoot, while increased the As (III) concentrations in the shoot of SY, MH and TH and in the root of MH. Furthermore, the As (III) concentrations in the root and shoot of SY were both the lowest among the treatments with the bacterium. On the other hand, its addition significantly alleviated the As (III) toxicity on four rice cultivars. Among the treatments amended with B. laterosporus, the bacterium showed the best remediation on SY seedlings, with respect to the subdued As (III) toxicity and decreased As (III) concentration in its roots. These results indicated that As (III) oxidation accelerated by B. laterosporus could be an effective method to alleviate As (III) toxicity on rice seedlings. PMID:26024808

  9. Calcium Supplementation Improves Na(+)/K(+) Ratio, Antioxidant Defense and Glyoxalase Systems in Salt-Stressed Rice Seedlings.

    PubMed

    Rahman, Anisur; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2016-01-01

    The present study investigates the regulatory role of exogenous calcium (Ca) in developing salt stress tolerance in rice seedlings. Hydroponically grown 13-day-old rice (Oryza sativa L. cv. BRRI dhan47) seedlings were exposed to 200 mM NaCl alone and combined with 2 mM CaCl2 and 2 mM ethylene glycol tetraacetic acid (EGTA, a Ca scavenger) for 3 days. The salt stress caused growth inhibition, chlorosis and water shortage in the rice seedlings. The salt-induced stress disrupted ion homeostasis through Na(+) influx and K(+) efflux, and decreased other mineral nutrient uptake. Salt stress caused oxidative stress in seedlings through lipid peroxidation, loss of plasma membrane integrity, higher reactive oxygen species (ROS) production and methylglyoxal (MG) formation. The salt-stressed seedlings supplemented with exogenous Ca recovered from water loss, chlorosis and growth inhibition. Calcium supplementation in the salt-stressed rice seedlings improved ion homeostasis by inhibition of Na(+) influx and K(+) leakage. Exogenous Ca also improved ROS and MG detoxification by improving the antioxidant defense and glyoxalase systems, respectively. On the other hand, applying EGTA along with salt and Ca again negatively affected the seedlings as EGTA negated Ca activity. It confirms that, the positive responses in salt-stressed rice seedlings to exogenous Ca were for Ca mediated improvement of ion homeostasis, antioxidant defense and glyoxalase system. PMID:27242816

  10. Zinc deficiency-inducible OsZIP8 encodes a plasma membrane-localized zinc transporter in rice.

    PubMed

    Lee, Sichul; Kim, Sun A; Lee, Joohyun; Guerinot, Mary Lou; An, Gynheung

    2010-06-01

    Zinc is an essential micronutrient for several physiological and biochemical processes. To investigate its transport in rice, we characterized OsZIP8, a rice ZIP (Zrt, Irt-like Protein) gene that is strongly up-regulated in shoots and roots under Zn deficiency. OsZIP8 could complement the growth defect of Zn-uptake yeast mutant. The OsZIP8-GFP fusion proteins were localized to the plasma membrane, suggesting that OsZIP8 is a plasma membrane zinc transporter in rice. Activation and overexpression of this gene disturbed the zinc distribution in rice plants, resulting in lower levels in shoots and mature seeds, but an increase in the roots. Field-grown transgenic plants were shorter than the WT. Under treatment with excess zinc, transgenics contained less zinc in their shoots but accumulated more in the roots. Altogether, these results demonstrate that OsZIP8 is a zinc transporter that functions in Zn uptake and distribution. Furthermore, zinc homeostasis is important to the proper growth and development of rice. PMID:20496122

  11. Assessment of rice leaf chlorophyll content using visible bands at different growth stages at both the leaf and canopy scale

    NASA Astrophysics Data System (ADS)

    Saberioon, M. M.; Amin, M. S. M.; Anuar, A. R.; Gholizadeh, A.; Wayayok, A.; Khairunniza-Bejo, S.

    2014-10-01

    Nitrogen is an important variable for paddy farming management. The objectives of this study were to develop and test a new method to determine the status of nitrogen and chlorophyll content in rice leaf by analysing and considering all visible bands derived from images captured using a conventional digital camera. The images from the 6-pannel leaf colour chart were acquired using Basler Scout scA640-70fc under light-emitting diode lighting, in which principal component analysis was used to retain the lower order principal component to develop a new index. Digital photographs of the upper most collared leaf of rice (Oriza sativa L.), grown over a range of soils with different nitrogen treatments, were processed into 11 indices and IPCA through six growth stages. Also a conventional digital camera mounted to an unmanned aerial vehicle was used to acquire images over the rice canopy for the purpose of verification. The result indicated that the conventional digital camera at the both leaf (r = -0.81) and the canopy (r = 0.78) scale could be used as a sensor to determine the status of chlorophyll content in rice plants through different growth stages. This indicates that conventional low-cost digital cameras can be used for determining chlorophyll content and consequently for monitoring nitrogen content of the growing rice plant, thus offering a potentially inexpensive, fast, accurate and suitable tool for rice growers. Additionally, results confirmed that a low cost LARS system would be well suited for high spatial and temporal resolution images and data analysis for proper assessment of key nutrients in rice farming in a fast, inexpensive and non-destructive way.

  12. Temperature-Related Yield Constraints of Early-Rice in South China: A Cross-Location Analysis

    PubMed Central

    Xie, Xiaobing; Zhou, Xuefeng; Cao, Fangbo; Zou, Yingbin

    2016-01-01

    Warm temperature during post-heading is generally hypothesized to be the critical factor limiting grain yield of early-rice in South China. However, there is no direct evidence to confirm this hypothesis in the field. This study was conducted to determine the temperature-related yield constraints of early-rice in South China. Field experiments were carried out in Huaiji (a location in South China) and Changsha (a location in the Yangtze River basin) in 2011–2013. In each year, two rice cultivars were grown in early-rice growing season in Huaiji and in single-rice growing season in Changsha. Huaiji had higher average daily maximum temperature during post-heading than Changsha. The higher temperature during post-heading induced early plant senescence (slower crop growth rate and shorter grain filling duration), but grain weight did not reduce because it was compensated for by increased translocation of pre-heading biomass. The higher temperature during post-heading also did not cause a reduction in grain filling percentage. Huaiji had lower temperature during pre-heading than Changsha, which to some extent resulted in slower crop growth rate and consequently lower biomass production and smaller sink size in Huaiji than in Changsha. As a result, grain yield was about 30% lower in Huaiji than in Changsha. Our results indicate that grain yield of early-rice in South China is limited not by warm temperature during post-heading but partially by cool temperature during pre-heading, and suggest that enhancing sink size and meanwhile maintaining good translocation of pre-heading biomass may be an effective way to achieve high yield for early-rice in South China. PMID:27366908

  13. From QTL to variety-harnessing the benefits of QTLs for drought, flood and salt tolerance in mega rice varieties of India through a multi-institutional network.

    PubMed

    Singh, Renu; Singh, Yashi; Xalaxo, Suchit; Verulkar, S; Yadav, Neera; Singh, Shweta; Singh, Nisha; Prasad, K S N; Kondayya, K; Rao, P V Ramana; Rani, M Girija; Anuradha, T; Suraynarayana, Y; Sharma, P C; Krishnamurthy, S L; Sharma, S K; Dwivedi, J L; Singh, A K; Singh, P K; Nilanjay; Singh, N K; Kumar, Rajesh; Chetia, S K; Ahmad, T; Rai, M; Perraju, P; Pande, Anita; Singh, D N; Mandal, N P; Reddy, J N; Singh, O N; Katara, J L; Marandi, B; Swain, P; Sarkar, R K; Singh, D P; Mohapatra, T; Padmawathi, G; Ram, T; Kathiresan, R M; Paramsivam, K; Nadarajan, S; Thirumeni, S; Nagarajan, M; Singh, A K; Vikram, Prashant; Kumar, Arvind; Septiningshih, E; Singh, U S; Ismail, A M; Mackill, D; Singh, Nagendra K

    2016-01-01

    Rice is a staple cereal of India cultivated in about 43.5Mha area but with relatively low average productivity. Abiotic factors like drought, flood and salinity affect rice production adversely in more than 50% of this area. Breeding rice varieties with inbuilt tolerance to these stresses offers an economically viable and sustainable option to improve rice productivity. Availability of high quality reference genome sequence of rice, knowledge of exact position of genes/QTLs governing tolerance to abiotic stresses and availability of DNA markers linked to these traits has opened up opportunities for breeders to transfer the favorable alleles into widely grown rice varieties through marker-assisted backcross breeding (MABB). A large multi-institutional project, "From QTL to variety: marker-assisted breeding of abiotic stress tolerant rice varieties with major QTLs for drought, submergence and salt tolerance" was initiated in 2010 with funding support from Department of Biotechnology, Government of India, in collaboration with International Rice Research Institute, Philippines. The main focus of this project is to improve rice productivity in the fragile ecosystems of eastern, northeastern and southern part of the country, which bear the brunt of one or the other abiotic stresses frequently. Seven consistent QTLs for grain yield under drought, namely, qDTY1.1, qDTY2.1, qDTY2.2, qDTY3.1, qDTY3.2, qDTY9.1 and qDTY12.1 are being transferred into submergence tolerant versions of three high yielding mega rice varieties, Swarna-Sub1, Samba Mahsuri-Sub1 and IR 64-Sub1. To address the problem of complete submergence due to flash floods in the major river basins, the Sub1 gene is being transferred into ten highly popular locally adapted rice varieties namely, ADT 39, ADT 46, Bahadur, HUR 105, MTU 1075, Pooja, Pratikshya, Rajendra Mahsuri, Ranjit, and Sarjoo 52. Further, to address the problem of soil salinity, Saltol, a major QTL for salt tolerance is being transferred into

  14. Structure, variation, and assembly of the root-associated microbiomes of rice

    PubMed Central

    Edwards, Joseph; Johnson, Cameron; Santos-Medellín, Christian; Lurie, Eugene; Podishetty, Natraj Kumar; Bhatnagar, Srijak; Eisen, Jonathan A.; Sundaresan, Venkatesan

    2015-01-01

    Plants depend upon beneficial interactions between roots and microbes for nutrient availability, growth promotion, and disease suppression. High-throughput sequencing approaches have provided recent insights into root microbiomes, but our current understanding is still limited relative to animal microbiomes. Here we present a detailed characterization of the root-associated microbiomes of the crop plant rice by deep sequencing, using plants grown under controlled conditions as well as field cultivation at multiple sites. The spatial resolution of the study distinguished three root-associated compartments, the endosphere (root interior), rhizoplane (root surface), and rhizosphere (soil close to the root surface), each of which was found to harbor a distinct microbiome. Under controlled greenhouse conditions, microbiome composition varied with soil source and genotype. In field conditions, geographical location and cultivation practice, namely organic vs. conventional, were factors contributing to microbiome variation. Rice cultivation is a major source of global methane emissions, and methanogenic archaea could be detected in all spatial compartments of field-grown rice. The depth and scale of this study were used to build coabundance networks that revealed potential microbial consortia, some of which were involved in methane cycling. Dynamic changes observed during microbiome acquisition, as well as steady-state compositions of spatial compartments, support a multistep model for root microbiome assembly from soil wherein the rhizoplane plays a selective gating role. Similarities in the distribution of phyla in the root microbiomes of rice and other plants suggest that conclusions derived from this study might be generally applicable to land plants. PMID:25605935

  15. The role of nodes in arsenic storage and distribution in rice

    PubMed Central

    Chen, Yi; Moore, Katie L.; Miller, Anthony J.; McGrath, Steve P.; Ma, Jian Feng; Zhao, Fang-Jie

    2015-01-01

    Knowledge of arsenic (As) accumulation in rice (Oryza sativa L.) is important for minimizing As transfer to the food chain. The aim of this study was to investigate the role of rice nodes in As storage and distribution. Synchrotron μX-ray fluorescence (μ-XRF) was used to map As distribution in the top node and internode of a lsi2 mutant defective in silicon/arsenite efflux carrier and its wild-type (WT) grown in soil. Lsi2 expression in different tissues during grain filling was investigated by quantitative RT-PCR. Arsenite or dimethylarsinic acid (DMA) was supplied to excised panicles to investigate the roles of Lsi2 and phytochelatins (PC) in As distribution. μ-XRF mapping revealed As storage in the phloem of different vascular bundles in the top node and internode. Soil-grown plants of lsi2 had markedly decreased As accumulation in the phloem compared with the WT. Lsi2 was strongly expressed, not only in the roots but also in the nodes. When excised panicles were exposed to As(III), the lsi2 mutant distributed more As to the node and flag leaf but less As to the grain compared with the WT, while there was no significant difference in DMA distribution. Inhibition of PC synthesis by l-buthionine-sulphoximine decreased As(III) deposition in the top node but increased As accumulation in the grain and flag leaf. The results suggest that rice nodes serve as a filter restricting As(III) distribution to the grain. Furthermore, Lsi2 plays a role in As(III) distribution in rice nodes and phytochelatins are important compounds for As(III) storage in the nodes. PMID:25922485

  16. Genome-wide transcriptome analysis of expression in rice seedling roots in response to supplemental nitrogen.

    PubMed

    Chandran, Anil Kumar Nalini; Priatama, Ryza A; Kumar, Vikranth; Xuan, Yuanhu; Je, Byoung Il; Kim, Chul Min; Jung, Ki-Hong; Han, Chang-Deok

    2016-08-01

    Nitrogen (N) is the most important macronutrient for plant growth and grain yields. For rice crops, nitrate and ammonium are the major N sources. To explore the genomic responses to ammonium supplements in rice roots, we used 17-day-old seedlings grown in the absence of external N that were then exposed to 0.5mM (NH4)2SO4 for 3h. Transcriptomic profiles were examined by microarray experiments. In all, 634 genes were up-regulated at least two-fold by the N-supplement when compared with expression in roots from untreated control plants. Gene Ontology (GO) enrichment analysis revealed that those upregulated genes are associated with 23 GO terms. Among them, metabolic processes for diverse amino acids (i.e., aspartate, threonine, tryptophan, glutamine, l-phenylalanine, and thiamin) as well as nitrogen compounds are highly over-represented, demonstrating that our selected genes are suitable for studying the N-response in roots. This enrichment analysis also indicated that nitrogen is closely linked to diverse transporter activities by primary metabolites, including proteins (amino acids), lipids, and carbohydrates, and is associated with carbohydrate catabolism and cell wall organization. Integration of results from omics analysis of metabolic pathways and transcriptome data using the MapMan tool suggested that the TCA cycle and pathway for mitochondrial electron transport are co-regulated when rice roots are exposed to ammonium. We also investigated the expression of N-responsive marker genes by performing a comparative analysis with root samples from plants grown under different NH4(+) treatments. The diverse responses to such treatment provide useful insight into the global changes related to the shift from an N-deficiency to an enhanced N-supply in rice, a model crop plant. PMID:27340859

  17. The role of nodes in arsenic storage and distribution in rice.

    PubMed

    Chen, Yi; Moore, Katie L; Miller, Anthony J; McGrath, Steve P; Ma, Jian Feng; Zhao, Fang-Jie

    2015-07-01

    Knowledge of arsenic (As) accumulation in rice (Oryza sativa L.) is important for minimizing As transfer to the food chain. The aim of this study was to investigate the role of rice nodes in As storage and distribution. Synchrotron μX-ray fluorescence (μ-XRF) was used to map As distribution in the top node and internode of a lsi2 mutant defective in silicon/arsenite efflux carrier and its wild-type (WT) grown in soil. Lsi2 expression in different tissues during grain filling was investigated by quantitative RT-PCR. Arsenite or dimethylarsinic acid (DMA) was supplied to excised panicles to investigate the roles of Lsi2 and phytochelatins (PC) in As distribution. μ-XRF mapping revealed As storage in the phloem of different vascular bundles in the top node and internode. Soil-grown plants of lsi2 had markedly decreased As accumulation in the phloem compared with the WT. Lsi2 was strongly expressed, not only in the roots but also in the nodes. When excised panicles were exposed to As(III), the lsi2 mutant distributed more As to the node and flag leaf but less As to the grain compared with the WT, while there was no significant difference in DMA distribution. Inhibition of PC synthesis by l-buthionine-sulphoximine decreased As(III) deposition in the top node but increased As accumulation in the grain and flag leaf. The results suggest that rice nodes serve as a filter restricting As(III) distribution to the grain. Furthermore, Lsi2 plays a role in As(III) distribution in rice nodes and phytochelatins are important compounds for As(III) storage in the nodes. PMID:25922485

  18. Structure, variation, and assembly of the root-associated microbiomes of rice.

    PubMed

    Edwards, Joseph; Johnson, Cameron; Santos-Medellín, Christian; Lurie, Eugene; Podishetty, Natraj Kumar; Bhatnagar, Srijak; Eisen, Jonathan A; Sundaresan, Venkatesan

    2015-02-24

    Plants depend upon beneficial interactions between roots and microbes for nutrient availability, growth promotion, and disease suppression. High-throughput sequencing approaches have provided recent insights into root microbiomes, but our current understanding is still limited relative to animal microbiomes. Here we present a detailed characterization of the root-associated microbiomes of the crop plant rice by deep sequencing, using plants grown under controlled conditions as well as field cultivation at multiple sites. The spatial resolution of the study distinguished three root-associated compartments, the endosphere (root interior), rhizoplane (root surface), and rhizosphere (soil close to the root surface), each of which was found to harbor a distinct microbiome. Under controlled greenhouse conditions, microbiome composition varied with soil source and genotype. In field conditions, geographical location and cultivation practice, namely organic vs. conventional, were factors contributing to microbiome variation. Rice cultivation is a major source of global methane emissions, and methanogenic archaea could be detected in all spatial compartments of field-grown rice. The depth and scale of this study were used to build coabundance networks that revealed potential microbial consortia, some of which were involved in methane cycling. Dynamic changes observed during microbiome acquisition, as well as steady-state compositions of spatial compartments, support a multistep model for root microbiome assembly from soil wherein the rhizoplane plays a selective gating role. Similarities in the distribution of phyla in the root microbiomes of rice and other plants suggest that conclusions derived from this study might be generally applicable to land plants. PMID:25605935

  19. [Amino acid composition of rice grain proteins].

    PubMed

    Peruanskiĭ, Iu V; Savich, I M

    1976-01-01

    The composition of the major reserve proteins of rice grain--globulins, prolamines and glutelins--was examined in four rice varieties (Dubovsky 129, Kuban 3, Alakul, Ushtobinsky). Globulins proved to be most heterogeneous whereas glutelins appeared to be least heterogeneous. In regards to the ratio of components globulins showed high variability and glutelins displayed high stability. PMID:1005365

  20. Grain Unloading Of Arsenic Species In Rice

    EPA Science Inventory

    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 dim...

  1. 33 CFR 117.324 - Rice Creek.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Rice Creek. 117.324 Section 117.324 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.324 Rice Creek. The CSX Railroad Swingbridge,...

  2. 33 CFR 117.324 - Rice Creek.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Rice Creek. 117.324 Section 117.324 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.324 Rice Creek. The CSX Railroad Swingbridge,...

  3. 33 CFR 117.324 - Rice Creek.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Rice Creek. 117.324 Section 117.324 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.324 Rice Creek. The CSX Railroad Swingbridge,...

  4. 33 CFR 117.324 - Rice Creek.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Rice Creek. 117.324 Section 117.324 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.324 Rice Creek. The CSX Railroad Swingbridge,...

  5. 33 CFR 117.324 - Rice Creek.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Rice Creek. 117.324 Section 117.324 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.324 Rice Creek. The CSX Railroad Swingbridge,...

  6. Simulating rice response to climate change

    SciTech Connect

    Singh, U.; Padilla, J.L. |

    1995-12-31

    The response of rice (Oryza sativa L.) to elevated CO{sub 2} concentration and temperature increase was simulated using the CERES-rice model. CERES-rice belongs to the International Benchmark Sites Network for Agrotechnology Transfer (IBSNAT) family of crop and nutrient dynamics models. Long-term historical data from the International Rice Research Institute (IRRI) wetland site was used to quantify the climatic change effects. The model simulated such beneficial effects of CO{sub 2} enrichment as increased grain yields, reduced transpiration, increased water use efficiency, improved use of intercepted radiation, reduced N losses, and higher N use efficiency. The trends were reversed for all of the above parameters with increase in temperature. CERES-rice simulated these negative trends in low input rice production as well. Based on the model`s prediction, some of the negative effects of temperature increase in warmer regions of the world could be offset by use of rice varieties that are tolerant to high temperature-induced spikelet sterility, and planting varieties with longer growth duration, particularly, longer grain filling duration. With improved varieties and good management future impact of climate change could be capitalized to have positive effects on rice production. Although the model has been extensively tested, it is critical to validate it with field data from extreme temperature and CO{sub 2} level studies. 33 refs., 13 figs., 3 tabs.

  7. Novel gene expression tools for rice biotechnology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biotechnology is an effective and important method of improving both quality and agronomic traits in rice. We are developing novel molecular tools for genetic engineering, with a focus on developing novel transgene expression control elements (i.e. promoters) for rice. A suite of monocot grass promo...

  8. Important sensory properties differentiating premium rice cultivars.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In rice-consuming countries worldwide, specific cultivars are recognized as premium, “gold standard” cultivars, while others are recognized as being superior, but not the best. It has been difficult to ascertain whether preferences for premium rice cultivars are driven by discernable differences in...

  9. Rice University: College and University Systems Environment.

    ERIC Educational Resources Information Center

    CAUSE/EFFECT, 1984

    1984-01-01

    Computing began at Rice University with the first computer project on campus about 1958. In 1960 a computer center was formed. Today's Institute for Computer Services and Applications serves Rice administration, departments, faculty, and students by writing systems, maintaining files, entering data, retrieving information, etc. (MLW)

  10. Evolutionary Genomics Of Invasive Weedy Rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice is an interfertile, weedy form of cultivated rice (Oryza sativa) that competes aggressively with the crop in the southern U.S., reducing yields and contaminating harvests. Weed strains range from ‘crop mimics,’ which share many domestication traits with the crop, to strains closely resembli...

  11. Rice blast evaluation of newly introduced germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic resistance to the rice blast fungus, Magnaporthe oryzae (anamorph Pyricularia grisea oryzae) was identified in newly introduced rice germplasm through quarantine when tested in artificially inoculated greenhouse and field nursery tests during the 2007 growing season. Of 229 accessions, 31 we...

  12. Connecting with Rice: Carolina Lowcountry and Africa

    ERIC Educational Resources Information Center

    Mitchell, Jerry T.; Collins, Larianne; Wise, Susan S.; Caughman, Monti

    2012-01-01

    Though lasting less than 200 years, large-scale rice production in South Carolina and Georgia "probably represented the most significant utilization of the tidewater zone for crop agriculture ever attained in the United States." Rice is a specialty crop where successful cultivation relied heavily upon "adaptation" to nature via imported…

  13. Low oil-uptake rice batters.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice starch and flour are popular for use in foods, because they are known to be nutritious, gluten-free, and hypoallergenic – properties which make them particularly desirable for use in infant foods, and in products for people with celiac disease (gluten intolerance). One application for rice sta...

  14. RICE BREAD FOR PEOPLE WITH CELIAC DISEASE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This technical bulletin was written to describe new process to make whole rice bread (WRB) for Celiacs, a disease caused by proteins found in wheat, barley and rye. The rice is free of these proteins and hence an ideal grain to develop foods for Celiacs. Absence of these proteins, however make it ...

  15. Rice yield estimation using Landsat ETM+ Data

    NASA Astrophysics Data System (ADS)

    Siyal, Altaf Ali; Dempewolf, Jan; Becker-Reshef, Inbal

    2015-01-01

    Paddy rice areas in Larkana district in Sindh province, Pakistan, were mapped over eight years. Landsat 7 ETM+ satellite imagery was classified for rice areas using training data collected through visual interpretation and using a bagged decision tree approach. Within the rice areas, we estimated yield for the 2013 season using regression models based on Landsat-derived normalized difference vegetation index (NDVI) and ratio vegetation index (RVI) values against historic, reported yield values. The annual cropped rice area estimated from satellite imagery was between 19% and 24% lower than the area reported by the Crop Reporting Service, Sindh. A positive and strong relationship with coefficient of determination (R2) of 0.94 was observed between the reported rice crop yield and NDVI at the peak of the growing season for the years 2006 to 2013. A fair relation (R2=0.875) between rice crop yield and RVI was observed for the same years. A strong relationship between observed and predicted rice production with model efficiency=0.925, mean bias error=-85,016 t, and RMSE=80,726 t was obtained. Thus, Landsat ETM+ has a high potential for estimating rice yield and production at the district level in Pakistan and elsewhere.

  16. Nutritionally-important starch fractions of rice cultivars grown in southern United States.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dietary starches can be classified into three major fractions, according to in vitro digestibility: rapidly digestible (RDS), slowly digestible (SDS), and resistant starch (RS). Literature indicates that SDS and/or RS have significant implications on human health, particularly, glucose metabolism, ...

  17. Harvesting microalgae grown on wastewater.

    PubMed

    Udom, Innocent; Zaribaf, Behnaz H; Halfhide, Trina; Gillie, Benjamin; Dalrymple, Omatoyo; Zhang, Qiong; Ergas, Sarina J

    2013-07-01

    The costs and life cycle impacts of microalgae harvesting for biofuel production were investigated. Algae were grown in semi-continuous culture in pilot-scale photobioreactors under natural light with anaerobic digester centrate as the feed source. Algae suspensions were collected and the optimal coagulant dosages for metal salts (alum, ferric chloride), cationic polymer (Zetag 8819), anionic polymer (E-38) and natural coagulants (Moringa Oleifera and Opuntia ficus-indica cactus) were determined using jar tests. The relative dewaterability of the algae cake was estimated by centrifugation. Alum, ferric chloride and cationic polymer could all achieve >91% algae recovery at optimal dosages. Life cycle assessment (LCA) and cost analysis results revealed that cationic polymer had the lowest cost but the highest environmental impacts, while ferric chloride had the highest cost and lowest environmental impacts. Based on the LCA results, belt presses are the recommended algae dewatering technology prior to oil extraction. PMID:23648758

  18. A Review of Microsatellite Markers and Their Applications in Rice Breeding Programs to Improve Blast Disease Resistance

    PubMed Central

    Miah, Gous; Rafii, Mohd Y.; Ismail, Mohd R.; Puteh, Adam B.; Rahim, Harun A.; Islam, Kh. Nurul; Latif, Mohammad Abdul

    2013-01-01

    Over the last few decades, the use of molecular markers has played an increasing role in rice breeding and genetics. Of the different types of molecular markers, microsatellites have been utilized most extensively, because they can be readily amplified by PCR and the large amount of allelic variation at each locus. Microsatellites are also known as simple sequence repeats (SSR), and they are typically composed of 1–6 nucleotide repeats. These markers are abundant, distributed throughout the genome and are highly polymorphic compared with other genetic markers, as well as being species-specific and co-dominant. For these reasons, they have become increasingly important genetic markers in rice breeding programs. The evolution of new biotypes of pests and diseases as well as the pressures of climate change pose serious challenges to rice breeders, who would like to increase rice production by introducing resistance to multiple biotic and abiotic stresses. Recent advances in rice genomics have now made it possible to identify and map a number of genes through linkage to existing DNA markers. Among the more noteworthy examples of genes that have been tightly linked to molecular markers in rice are those that confer resistance or tolerance to blast. Therefore, in combination with conventional breeding approaches, marker-assisted selection (MAS) can be used to monitor the presence or lack of these genes in breeding populations. For example, marker-assisted backcross breeding has been used to integrate important genes with significant biological effects into a number of commonly grown rice varieties. The use of cost-effective, finely mapped microsatellite markers and MAS strategies should provide opportunities for breeders to develop high-yield, blast resistance rice cultivars. The aim of this review is to summarize the current knowledge concerning the linkage of microsatellite markers to rice blast resistance genes, as well as to explore the use of MAS in rice breeding

  19. The roots of future rice harvests.

    PubMed

    Ahmadi, Nourollah; Audebert, Alain; Bennett, Malcolm J; Bishopp, Anthony; de Oliveira, Antonio Costa; Courtois, Brigitte; Diedhiou, Abdala; Diévart, Anne; Gantet, Pascal; Ghesquière, Alain; Guiderdoni, Emmanuel; Henry, Amelia; Inukai, Yoshiaki; Kochian, Leon; Laplaze, Laurent; Lucas, Mikael; Luu, Doan Trung; Manneh, Baboucarr; Mo, Xiaorong; Muthurajan, Raveendran; Périn, Christophe; Price, Adam; Robin, Sabariappan; Sentenac, Hervé; Sine, Bassirou; Uga, Yusaku; Véry, Anne Aliénor; Wissuwa, Matthias; Wu, Ping; Xu, Jian

    2014-12-01

    Rice production faces the challenge to be enhanced by 50% by year 2030 to meet the growth of the population in rice-eating countries. Whereas yield of cereal crops tend to reach plateaus and a yield is likely to be deeply affected by climate instability and resource scarcity in the coming decades, building rice cultivars harboring root systems that can maintain performance by capturing water and nutrient resources unevenly distributed is a major breeding target. Taking advantage of gathering a community of rice root biologists in a Global Rice Science Partnership workshop held in Montpellier, France, we present here the recent progresses accomplished in this area and focal points where an international network of laboratories should direct their efforts. PMID:26224558

  20. Understanding of evolutionary genomics of invasive species of rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice is an aggressive, weedy form of cultivated rice (Oryza sativa) that infests crop fields and is a primary factor limiting rice productivity in the U.S. and worldwide. As the weedy relative of a genomic model species, red rice is a model for understanding the genetic and evolutionary mechani...

  1. Elucidation of molecular dynamics of invasive species of rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cultivated rice fields are aggressively invaded by weedy rice in the U.S. and worldwide. Weedy rice results in loss of yield and seed contamination. The molecular dynamics of the evolutionary adaptive traits of weedy rice are not fully understood. To understand the molecular basis and identify the i...

  2. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  3. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  4. Agronomic potential of southern rice cultivars under organic management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic rice production is expanding in the United States as a result of increasing market demand. Although acreage of conventional produced rice has declined in Texas over the last twenty years, organic rice production has increased to almost ten percent of the Texas rice acreage. Organic growers ...

  5. Modification of physical properties of freeze-dried rice

    NASA Technical Reports Server (NTRS)

    Huber, C. S.

    1971-01-01

    Freeze cycling process consists of alternately freezing and thawing precooked rice for two cycles, rice is then frozen and freeze-dehydrated in vacuum sufficient to remove water from rice by sublimitation. Process modifies rice grain structure and porosity, enabling complete rehydration in one minute in hot water.

  6. 7 CFR 868.201 - Definition of rough rice.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Definition of rough rice. 868.201 Section 868.201... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Rough Rice Terms Defined § 868.201 Definition of rough rice. Rice (Oryza sativa L.) which consists of 50 percent or more of paddy kernels...

  7. 7 CFR 868.301 - Definition of milled rice.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Definition of milled rice. 868.301 Section 868.301... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Milled Rice Terms Defined § 868.301 Definition of milled rice. Whole or broken kernels of rice (Oryza sativa L.) from which the hulls and...

  8. 7 CFR 868.301 - Definition of milled rice.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Definition of milled rice. 868.301 Section 868.301... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Milled Rice Terms Defined § 868.301 Definition of milled rice. Whole or broken kernels of rice (Oryza sativa L.) from which the hulls and...

  9. 7 CFR 868.201 - Definition of rough rice.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Definition of rough rice. 868.201 Section 868.201... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Rough Rice Terms Defined § 868.201 Definition of rough rice. Rice (Oryza sativa L.) which consists of 50 percent or more of paddy kernels...

  10. 7 CFR 868.201 - Definition of rough rice.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Definition of rough rice. 868.201 Section 868.201... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Rough Rice Terms Defined § 868.201 Definition of rough rice. Rice (Oryza sativa L.) which consists of 50 percent or more of paddy kernels...

  11. 7 CFR 868.301 - Definition of milled rice.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Definition of milled rice. 868.301 Section 868.301... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Milled Rice Terms Defined § 868.301 Definition of milled rice. Whole or broken kernels of rice (Oryza sativa L.) from which the hulls and...

  12. 7 CFR 868.201 - Definition of rough rice.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Definition of rough rice. 868.201 Section 868.201... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Rough Rice Terms Defined § 868.201 Definition of rough rice. Rice (Oryza sativa L.) which consists of 50 percent or more of paddy kernels...

  13. 7 CFR 868.301 - Definition of milled rice.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Definition of milled rice. 868.301 Section 868.301... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Milled Rice Terms Defined § 868.301 Definition of milled rice. Whole or broken kernels of rice (Oryza sativa L.) from which the hulls and...

  14. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  15. 7 CFR 868.201 - Definition of rough rice.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Definition of rough rice. 868.201 Section 868.201... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Rough Rice Terms Defined § 868.201 Definition of rough rice. Rice (Oryza sativa L.) which consists of 50 percent or more of paddy kernels...

  16. 7 CFR 868.301 - Definition of milled rice.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Definition of milled rice. 868.301 Section 868.301... FOR CERTAIN AGRICULTURAL COMMODITIES United States Standards for Milled Rice Terms Defined § 868.301 Definition of milled rice. Whole or broken kernels of rice (Oryza sativa L.) from which the hulls and...

  17. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is the refined wax obtained from rice bran and meets the...

  18. Rice Bran: Production, Composition, Functionality and Food Applications, Physiological Benefits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal and human studies show cholesterol-lowering with rice bran in hypercholesterolemic individuals. Specific rice bran fractions showing hypocholesterolemic activity include rice bran oil, unsaponifiable matter, dietary fiber and protein. There is a dose response to the level of rice bran and r...

  19. Identifying novel resistance genes in rice wild relatives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast and sheath blight are major fungal diseases of cultivated rice (Oryza sativa L. ) that limit Arkansas rough rice yields and market potential. Resistance to these diseases has been found in rice wild relatives (Oryza spp.) A collection of these wild relatives originating from outside the U...

  20. Identification of Some Degradation Products of Golden Rice Beta- carotene

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Golden Rice (GR2) is genetically modified rice, which can contain as high as 37 ug of beta-carotene per g of dry rice. It was developed to combat vitamin A deficiency (VAD), a major malnutrition problem in many parts of the developing world, especially in South and South Eastern Asia, where rice is ...

  1. Analysis of genotypic diversity in esterase activity of rice bran

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice bran is a by-product of the rice milling process. It is rich in protein, fat, crude fiber, minerals and vitamins, and is a valuable source of antioxidants. It can be used for ingredients, be developed into a functional food, and can be extracted for rice bran oil production. However, rice bran ...

  2. Utilization of trait-linked DNA markers in rice breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA marker technology is being used in U.S. rice breeding programs to enhance development of rice cultivars with improved cooking quality and genetic resistance to rice blast disease. Because there is a continuous threat of race shifts within the Magnaporthe grisea populations found in rice fields t...

  3. Golden Rice is an effective source for vitamin A

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetically engineered "Golden Rice" contains up to 35 ug Beta-carotene per gram of rice. It is important to determine the vitamin A equivalency of Golden Rice Beta-carotene to project the potential effect of this biofortified grain in rice-consuming populations that commonly exhibit low vitamin A s...

  4. Selenium addition alters mercury uptake, bioavailability in the rhizosphere and root anatomy of rice (Oryza sativa)

    PubMed Central

    Wang, Xun; Tam, Nora Fung-Yee; Fu, Shi; Ametkhan, Aray; Ouyang, Yun; Ye, Zhihong

    2014-01-01

    Background and Aims Mercury (Hg) is an extremely toxic pollutant, especially in the form of methylmercury (MeHg), whereas selenium (Se) is an essential trace element in the human diet. This study aimed to ascertain whether addition of Se can produce rice with enriched Se and lowered Hg content when growing in Hg-contaminated paddy fields and, if so, to determine the possible mechanisms behind these effects. Methods Two cultivars of rice (Oryza sativa, japonica and indica) were grown in either hydroponic solutions or soil rhizobags with different Se and Hg treatments. Concentrations of total Hg, MeHg and Se were determined in the roots, shoots and brown rice, together with Hg uptake kinetics and Hg bioavailability in the soil. Root anatonmy was also studied. Key Results The high Se treatment (5 μg g–1) significantly increased brown rice yield by 48 % and total Se content by 2·8-fold, and decreased total Hg and MeHg by 47 and 55 %, respectively, compared with the control treatments. The high Se treatment also markedly reduced ‘water-soluble’ Hg and MeHg concentrations in the rhizosphere soil, decreased the uptake capacity of Hg by roots and enhanced the development of apoplastic barriers in the root endodermis. Conclusions Addition of Se to Hg-contaminated soil can help produce brown rice that is simultaneously enriched in Se and contains less total Hg and MeHg. The lowered accumulation of total Hg and MeHg appears to be the result of reduced bioavailability of Hg and production of MeHg in the rhizosphere, suppression of uptake of Hg into the root cells and an enhancement of the development of apoplastic barriers in the endodermis of the roots. PMID:24948669

  5. Colonization of rice roots with methanogenic archaea controls photosynthesis-derived methane emission.

    PubMed

    Pump, Judith; Pratscher, Jennifer; Conrad, Ralf

    2015-07-01

    The methane emitted from rice fields originates to a large part (up to 60%) from plant photosynthesis and is formed on the rice roots by methanogenic archaea. To investigate to which extent root colonization controls methane (CH4 ) emission, we pulse-labeled rice microcosms with (13) CO2 to determine the rates of (13) CH4 emission exclusively derived from photosynthates. We also measured emission of total CH4 ((12+13) CH4 ), which was largely produced in the soil. The total abundances of archaea and methanogens on the roots and in the soil were analysed by quantitative polymerase chain reaction of the archaeal 16S rRNA gene and the mcrA gene coding for a subunit of the methyl coenzyme M reductase respectively. The composition of archaeal and methanogenic communities was determined with terminal restriction fragment length polymorphism (T-RFLP). During the vegetative growth stages, emission rates of (13) CH4 linearly increased with the abundance of methanogenic archaea on the roots and then decreased during the last plant growth stage. Rates of (13) CH4 emission and the abundance of methanogenic archaea were lower when the rice was grown in quartz-vermiculite with only 10% rice soil. Rates of total CH4 emission were not systematically related to the abundance of methanogenic archaea in soil plus roots. The composition of the archaeal communities was similar under all conditions; however, the analysis of mcrA genes indicated that the methanogens differed between the soil and root. Our results support the hypothesis that rates of photosynthesis-driven CH4 emission are limited by the abundance of methanogens on the roots. PMID:25367104

  6. Impact of model uncertainty on soil quality standards for cadmium in rice paddy fields.

    PubMed

    Römkens, P F A M; Brus, D J; Guo, H Y; Chu, C L; Chiang, C M; Koopmans, G F

    2011-08-01

    At present, soil quality standards used for agriculture do not consider the influence of pH and CEC on the uptake of pollutants by crops. A database with 750 selected paired samples of cadmium (Cd) in soil and paddy rice was used to calibrate soil to plant transfer models using the soil metal content, pH, and CEC or soil Cd and Zn extracted by 0.01 M CaCl₂ as explanatory variables. The models were validated against a set of 2300 data points not used in the calibration. These models were then used inversely to derive soil quality standards for Japonica and Indica rice cultivars based on the food quality standards for rice. To account for model uncertainty, strict soil quality standards were derived considering a maximum probability that rice exceeds the food quality standard equal to 10 or 5%. Model derived soil standards based on Aqua Regia ranged from less than 0.3 mg kg⁻¹ for Indica at pH 4.5 to more than 6 mg kg⁻¹ for Japonica-type cultivars in clay soils at pH 7. Based on the CaCl₂ extract, standards ranged from 0.03 mg kg⁻¹ Cd for Indica cultivars to 0.1 mg kg⁻¹ Cd for Japonica cultivars. For both Japonica and Indica-type cultivars, the soil quality standards must be reduced by a factor of 2 to 3 to obtain the strict standards. The strong impact of pH and CEC on soil quality standards implies that it is essential to correct for soil type when deriving national or local standards. Validation on the remaining 2300 samples indicated that both types of models were able to accurately predict (> 92%) whether rice grown on a specific soil will meet the food quality standard used in Taiwan. PMID:21632090

  7. Rice Domestication Revealed by Reduced Shattering of Archaeological rice from the Lower Yangtze valley

    PubMed Central

    Zheng, Yunfei; Crawford, Gary W.; Jiang, Leping; Chen, Xugao

    2016-01-01

    Plant remains dating to between 9000 and 8400 BP from a probable ditch structure at the Huxi site include the oldest rice (Oryza sativa) spikelet bases and associated plant remains recovered in China. The remains document an early stage of rice domestication and the ecological setting in which early cultivation was taking place. The rice spikelet bases from Huxi include wild (shattering), intermediate, and domesticated (non-shattering) forms. The relative frequency of intermediate and non-shattering spikelet bases indicates that selection for, at the very least, non-shattering rice was underway at Huxi. The rice also has characteristics of japonica rice (Oryza sativa subsp. japonica), helping to clarify the emergence of a significant lineage of the crop. Seeds, phytoliths and their context provide evidence of increasing anthropogenesis and cultivation during the occupation. Rice spikelet bases from Kuahuqiao (8000–7700 BP), Tianluoshan (7000–6500 BP), Majiabang (6300–6000 BP), and Liangzhu (5300–4300 BP) sites indicate that rice underwent continuing selection for reduced shattering and japonica rice characteristics, confirming a prolonged domestication process for rice. PMID:27324699

  8. Rice Domestication Revealed by Reduced Shattering of Archaeological rice from the Lower Yangtze valley.

    PubMed

    Zheng, Yunfei; Crawford, Gary W; Jiang, Leping; Chen, Xugao

    2016-01-01

    Plant remains dating to between 9000 and 8400 BP from a probable ditch structure at the Huxi site include the oldest rice (Oryza sativa) spikelet bases and associated plant remains recovered in China. The remains document an early stage of rice domestication and the ecological setting in which early cultivation was taking place. The rice spikelet bases from Huxi include wild (shattering), intermediate, and domesticated (non-shattering) forms. The relative frequency of intermediate and non-shattering spikelet bases indicates that selection for, at the very least, non-shattering rice was underway at Huxi. The rice also has characteristics of japonica rice (Oryza sativa subsp. japonica), helping to clarify the emergence of a significant lineage of the crop. Seeds, phytoliths and their context provide evidence of increasing anthropogenesis and cultivation during the occupation. Rice spikelet bases from Kuahuqiao (8000-7700 BP), Tianluoshan (7000-6500 BP), Majiabang (6300-6000 BP), and Liangzhu (5300-4300 BP) sites indicate that rice underwent continuing selection for reduced shattering and japonica rice characteristics, confirming a prolonged domestication process for rice. PMID:27324699

  9. Can the co-cultivation of rice and fish help sustain rice production?

    PubMed Central

    Hu, Liangliang; Zhang, Jian; Ren, Weizheng; Guo, Liang; Cheng, Yongxu; Li, Jiayao; Li, Kexin; Zhu, Zewen; Zhang, Jiaen; Luo, Shiming; Cheng, Lei; Tang, Jianjun; Chen, Xin

    2016-01-01

    Because rice feeds half of the world’s population, a secure global food supply depends on sustainable rice production. Here we test whether the co-cultivation of rice and fish into one “rice-fish system” (RFS; fish refers to aquatic animals in this article) could help sustain rice production. We examined intensive and traditional RFSs that have been widely practiced in China. We found that rice yields did not decrease when fish yield was below a threshold value in each intensive RFS. Below the thresholds, moreover, fish yields in intensive RFSs can be substantially higher than those in traditional RFS without reducing rice yield. Relative to rice monoculture, the use of fertilizer-nitrogen and pesticides decreased, and the farmers’ net income increased in RFSs. The results suggest that RFSs can help sustain rice production, and suggest that development of co-culture technologies (i.e. proper field configuration for fish and rice) is necessary to achieve the sustainability. PMID:27349875

  10. RiceWiki: a wiki-based database for community curation of rice genes.

    PubMed

    Zhang, Zhang; Sang, Jian; Ma, Lina; Wu, Gang; Wu, Hao; Huang, Dawei; Zou, Dong; Liu, Siqi; Li, Ang; Hao, Lili; Tian, Ming; Xu, Chao; Wang, Xumin; Wu, Jiayan; Xiao, Jingfa; Dai, Lin; Chen, Ling-Ling; Hu, Songnian; Yu, Jun

    2014-01-01

    Rice is the most important staple food for a large part of the world's human population and also a key model organism for biological studies of crops as well as other related plants. Here we present RiceWiki (http://ricewiki.big.ac.cn), a wiki-based, publicly editable and open-content platform for community curation of rice genes. Most existing related biological databases are based on expert curation; with the exponentially exploding volume of rice knowledge and other relevant data, however, expert curation becomes increasingly laborious and time-consuming to keep knowledge up-to-date, accurate and comprehensive, struggling with the flood of data and requiring a large number of people getting involved in rice knowledge curation. Unlike extant relevant databases, RiceWiki features harnessing collective intelligence in community curation of rice genes, quantifying users' contributions in each curated gene and providing explicit authorship for each contributor in any given gene, with the aim to exploit the full potential of the scientific community for rice knowledge curation. Based on community curation, RiceWiki bears the potential to make it possible to build a rice encyclopedia by and for the scientific community that harnesses community intelligence for collaborative knowledge curation, covers all aspects of biological knowledge and keeps evolving with novel knowledge. PMID:24136999

  11. Glycaemic index of some commercially available rice and rice products in Great Britain.

    PubMed

    Ranawana, D V; Henry, C J K; Lightowler, H J; Wang, D

    2009-01-01

    The glycaemic response to nine types of rice (white basmati, brown basmati, white and brown basmati, easy-cook basmati, basmati and wild rice, long-grain rice, easy-cook long-grain rice, Thai red rice, Thai glutinous rice) and two types of rice vermicelli (Guilin rice vermicelli, Jiangxi rice vermicelli) commercially available in the United Kingdom were compared against a glucose standard in a non-blind, randomized, repeated-measure, crossover design trial. Fourteen healthy subjects (six males, eight females), mean age 38 (standard deviation 16) years and mean body mass index 21.3 (standard deviation 2.3) kg/m(2), were recruited for the study. Subjects were served portions of the test foods and a standard food (glucose), on separate occasions, each containing 50 g available carbohydrates. Capillary blood glucose was measured from finger-prick samples in fasted subjects (-5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min after the consumption of each test food. For each type of food, its glycaemic index (GI) was calculated geometrically by expressing the incremental area under the blood glucose curve as a percentage of each subject's average incremental area under the blood glucose curve for the standard food. The 10 foods exhibited a range of GI values from 37 to 92. The study indicated that rice noodles, long-grain rice, easy-cook long-grain rice and white basmati rice were low-GI foods, whilst all of the other foods were medium-GI and high-GI foods. The information presented in this paper may be useful in helping people select low-GI foods from the customary foods consumed by the British and Asian populations. PMID:19169946

  12. Structure Analysis of Several Red Rice Populations in Arkansas: DNA Marker Evidence for Gene Flow with Rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice is a troublesome weed problem in Arkansas rice fields and numerous biotypes are present. Outcrossing between rice and red rice occurs at low rates, resulting in unusual plant types, and can complicate weed management efforts. STRUCTURE analysis of DNA SSR marker data is useful to infer po...

  13. 7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Administrative instructions relating to entry of rice straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture Regulations of the Department of... QUARANTINE NOTICES Rice Quarantine § 319.55a Administrative instructions relating to entry of rice straw...

  14. 7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Administrative instructions relating to entry of rice straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture Regulations of the Department of... QUARANTINE NOTICES Rice Quarantine § 319.55a Administrative instructions relating to entry of rice straw...

  15. 7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Administrative instructions relating to entry of rice straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture Regulations of the Department of... QUARANTINE NOTICES Rice Quarantine § 319.55a Administrative instructions relating to entry of rice straw...

  16. 7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Administrative instructions relating to entry of rice straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture Regulations of the Department of... QUARANTINE NOTICES Rice Quarantine § 319.55a Administrative instructions relating to entry of rice straw...

  17. 7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Administrative instructions relating to entry of rice straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture Regulations of the Department of... QUARANTINE NOTICES Rice Quarantine § 319.55a Administrative instructions relating to entry of rice straw...

  18. Analysis of rice blast resistance gene Pi-z in rice germplasm using pathogenicity assays and DNA markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Pi-z(t) gene in rice confers resistance to a wide range of races of the rice blast fungus, Magnaporthe oryzae. The objective of this study was to characterize Pi-z(t) in 117 rice germplasm accessions using DNA markers and pathogenicity assays. The existence of Pi-z(t) in rice germplasm was detec...

  19. Evolutionary dynamics and structure of the rice blast resistance locus Pi-ta in wild, cultivated, and US weedy rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Pi-ta gene in rice has been used to control rice blast pathogen, Magnaporthe oryza, in rice growing areas worldwide for decades. To understand the evolutionary process and natural selection of Pi-ta during rice domestication, we first examined sequences of the genomic region of Pi-ta in geograph...

  20. MULTI-YEAR EVALUATION OF RECIPROCAL OUTCROSSING RATES BETWEEN SELECTED RICE CULTIVARS AND RED RICE TYPES AT STUTTGART, ARKANSAS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Arkansas various reports and observations have long indicated that hybridization between rice and red rice in farm fields can occur with either of these rice types serving as the pollen donor (male) or pollen acceptor (female). Reliable measurements of the outcrossing rates between rice and red ...

  1. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    NASA Astrophysics Data System (ADS)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L. D.; Anuntalabhochai, S.

    2013-07-01

    Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60-80 keV to a beam fluence range of 2 × 1016-2 × 1017 ions/cm2. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 106 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11).

  2. [Safety of rice grains and mycotoxins - a historical review of yellow rice mycotoxicoses].

    PubMed

    Udagawa, Shun-ichi; Tatsuno, Takashi

    2004-01-01

    Aflatoxins, the most powerful mycotoxins, were brought to the attention fo the people in the early 1960s with the outbreak of the turkey "X" disease in England. However, the history of mycotoxin research in Japan began 100 years ago. In 1891, Sakaki demonstrated that moldy, unpolished rice was fatal to experimental animals, with symptoms indicating paralysis of the central nervous system (Shoshin-kakke). In 1920, Prof. I. Miyake and Dr. Takada first reported that Penicillium commune, which was known as a causal agent of "Mossy diseased rice" was found to be toxic to experimental animals by feeding the moldy rice to rabbits and rats.With such a historical background, taking the idea of "rice, fungus and toxin" as a working hypothesis, Miyake and his co-workers discovered the first sample of yellow rice grains from Taiwanese and domestic rice, from which was isolated a species of Penicillium and later identified it with P. citreonigrum (=P. toxicarium). The fungus produced a highly toxic metabolite, citreoviridin. Unfortunately because this study was published during wartime, it failed to alert the world to the potential or actual dangers of the toxicity of common molds. After World War II, Japanese people suffered for some years from a shortage in domestic rice production and depended on foreign countries to supply rice, which led to the toxicological screening on fungal isolates from polluted rice grains by Dr. Tsunoda and his co-workers. AMong the isolates from imported rice, there were two species of Penicillium which were particularly associated with high toxicity; P. islandicum responsible for brownish discolored rice, and P. citrinum responsible for yellowish rice. P. islandicum produces two hepatotoxic metabolites: luteoskyrin and cyclochlorotine, while a nephrotoxic of P. citrinum is citrinin. These toxicological characters, including the induction of cancer and chemical structures, were studied by Profs. uraguchi, Saito, Shibata, Tatsuno and their co

  3. Changes in the mitochondrial proteome during the anoxia to air transition in rice focus around cytochrome-containing respiratory complexes.

    PubMed

    Millar, A Harvey; Trend, Alice E; Heazlewood, Joshua L

    2004-09-17

    The ability of rice seedlings to grow from dry seed under anoxia provides a rare opportunity in a multicellular eukaryote to study the stages of mitochondrial biogenesis triggered by oxygen availability. The function and proteome of rice mitochondria synthesized under 6 days of anoxia following 1 day of air adaptation have been compared with mitochondria isolated from 7-day aerobically grown rice seedlings. Rice coleoptiles grown under anoxia, and the mitochondria isolated from them respired very slowly compared with air-adapted and air-grown seedlings. Immunodetection of key mitochondrial protein markers, isoelectric focusing electrophoresis followed by SDS-PAGE to make soluble mitochondria proteome maps, and shotgun sequencing of mitochondrial proteins by liquid chromatography-tandem mass spectrometry all revealed similar patterns of the major function categories of mitochondrial proteins from both anoxic and air-adapted samples. Activity analysis showed respiratory oxidases markedly increased in activity during the air adaptation of seedlings. Blue-native electrophoresis followed by SDS-PAGE of mitochondrial membrane proteins clearly showed the very low abundance of assembled b/c complex and cytochrome c(1) oxidase complex in the mitochondrial membrane in anoxic samples and the dramatic increase in the abundance of these complexes on air adaptation. Total heme content, cytochrome absorbance spectra, and the electron carrier, cytochrome c, also increased markedly on air adaptation. These results likely reflect limited heme synthesis for cytochrome assembly in the absence of oxygen and represent a discrete and reversible blockage of full mitochondrial biogenesis in this anoxia-tolerant species. PMID:15258153

  4. Urinary excretion of arsenic following rice consumption.

    PubMed

    Meharg, A A; Williams, P N; Deacon, C M; Norton, G J; Hossain, M; Louhing, D; Marwa, E; Lawgalwi, Y; Taggart, M; Cascio, C; Haris, P

    2014-11-01

    Patterns of arsenic excretion were followed in a cohort (n = 6) eating a defined rice diet, 300 g per day d.wt. where arsenic speciation was characterized in cooked rice, following a period of abstinence from rice, and other high arsenic containing foods. A control group who did not consume rice were also monitored. The rice consumed in the study contained inorganic arsenic and dimethylarsinic acid (DMA) at a ratio of 1:1, yet the urine speciation was dominated by DMA (90%). At steady state (rice consumption/urinary excretion) ∼40% of rice derived arsenic was excreted via urine. By monitoring of each urine pass throughout the day it was observed that there was considerable variation (up to 13-fold) for an individual's total arsenic urine content, and that there was a time dependent variation in urinary total arsenic content. This calls into question the robustness of routinely used first pass/spot check urine sampling for arsenic analysis. PMID:25145278

  5. Response of aerobic rice to Piriformospora indica.

    PubMed

    Das, Joy; Ramesh, K V; Maithri, U; Mutangana, D; Suresh, C K

    2014-03-01

    Rice cultivation under aerobic condition not only saves water but also opens up a splendid scope for effective application of beneficial root symbionts in rice crop unlike conventional puddled rice cultivation where water logged condition acts as constraint for easy proliferation of various beneficial soil microorganisms like arbuscular mycorrhizal (AM) fungi. Keeping these in view, an in silico investigation were carried out to explore the interaction of hydrogen phosphate with phosphate transporter protein (PTP) from P. indica. This was followed by greenhouse investigation to study the response of aerobic rice to Glomusfasciculatum, a conventional P biofertilizer and P. indica, an alternative to AM fungi. Computational studies using ClustalW tool revealed several conserved motifs between the phosphate transporters from Piriformospora indica and 8 other Glomus species. The 3D model of PTP from P. indica resembling "Mayan temple" was successfully docked onto hydrogen phosphate, indicating the affinity of this protein for inorganic phosphorus. Greenhouse studies revealed inoculation of aerobic rice either with P. indica, G. fasciculatum or both significantly enhanced the plant growth, biomass and yield with higher NPK, chlorophyll and sugar compared to uninoculated ones, P. indica inoculated plants being superior. A significantly enhanced activity of acid phosphatase and alkaline phosphatase were noticed in the rhizosphere soil of rice plants inoculated either with P. indica, G. fasciculatum or both, contributing to higher P uptake. Further, inoculation of aerobic rice plants with P. indica proved to be a better choice as a potential biofertilizer over mycorrhiza. PMID:24669667

  6. Phenolic compounds and bioactivities of pigmented rice.

    PubMed

    Deng, Gui-Fang; Xu, Xiang-Rong; Zhang, Yuan; Li, Dan; Gan, Ren-You; Li, Hua-Bin

    2013-01-01

    The pigmented rice has been consumed in China, Japan, and Korea for a long time. It has been used for strengthening kidney function, treating anemia, promoting blood circulation, removing blood stasis, treating diabetes, and ameliorating sight in traditional Chinese medicine. The extracts from pigmented rice are used as natural food colorants in bread, ice cream, and liquor as well as functional food. The pigmented rice is mainly black, red, and dark purple rice, and contains a variety of flavones, tannin, phenolics, sterols, tocols, γ-oryzanols, amino acids, and essential oils. Anthocyanins are thought as major functional components of pigmented rice. Several anthocyanins have been isolated and identified from the pigmented rice, including cyanidin 3-glucoside, cyanidin 3-galactoside, cyanidin 3-rutinoside, cyanidin 3,5-diglucoside, malvidin 3-galactoside, peonidin 3-glucoside, and pelargonidin 3,5-diglucoside. This review provides up-to-date coverage of pigmented rice in regard to bioactive constituents, extraction and analytical methods, and bioactivities. Special attention is paid to the bioactivities including antioxidant and free radical scavenging, antitumor, antiatherosclerosis, hypoglycemic, and antiallergic activities. PMID:23216001

  7. An update on the use of co-products from the milling of rice in value added food products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because of the huge quantity of rice produced annually, milled-rice co-products; such as, rice bran, rice oil, rice wax, rice flour, and rice hull are plentiful and readily available. These co-products could be valuable sources of food ingredients, but they have been vastly under-utilized. Rice bra...

  8. Cooling by means of passively grown ice

    SciTech Connect

    Gorski, A.; Schertz, W.; Wantroba, A.; Rush, R.; Falkenberg, J.

    1981-01-01

    A solar cooling technique is described that uses ice passively-grown the previous winter. Using heat pipes (thermal syphons), ice is grown and stored in the same container ready for the coming cooling season. This modern adaption of an old cooling technique may have side application both in this country as well as in more northern regions.

  9. Vitamin C content of organically grown produce

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organically grown produce is the fastest growing sector of fresh market sales in the U.S. While accounting for only 3% of total produce sales, it is growing by 20% per year. There has been much debate over the relative health merits of organically grown fruits and vegetables. Most consumers believ...

  10. Rice hull energy uses in the Philippines

    SciTech Connect

    Waddle, D.B.

    1985-01-01

    As a rice producing country, the Philippines produces a tremendous amount of rice hulls which when converted to energy could displace a substantial amount of imported energy. Realizing this possibility needs a thorough evaluation of both resources and demand characteristics of particular industry where immediate applicability of technical option awaits. This document presents the Philippines' past activities in fuelizing rice hulls and future action plans where its economic relevance could be enhanced. Descriptions of four power plants are included with the author's analysis of their probable market impact and projections of future applications.

  11. A map of rice genome variation reveals the origin of cultivated rice.

    PubMed

    Huang, Xuehui; Kurata, Nori; Wei, Xinghua; Wang, Zi-Xuan; Wang, Ahong; Zhao, Qiang; Zhao, Yan; Liu, Kunyan; Lu, Hengyun; Li, Wenjun; Guo, Yunli; Lu, Yiqi; Zhou, Congcong; Fan, Danlin; Weng, Qijun; Zhu, Chuanrang; Huang, Tao; Zhang, Lei; Wang, Yongchun; Feng, Lei; Furuumi, Hiroyasu; Kubo, Takahiko; Miyabayashi, Toshie; Yuan, Xiaoping; Xu, Qun; Dong, Guojun; Zhan, Qilin; Li, Canyang; Fujiyama, Asao; Toyoda, Atsushi; Lu, Tingting; Feng, Qi; Qian, Qian; Li, Jiayang; Han, Bin

    2012-10-25

    Crop domestications are long-term selection experiments that have greatly advanced human civilization. The domestication of cultivated rice (Oryza sativa L.) ranks as one of the most important developments in history. However, its origins and domestication processes are controversial and have long been debated. Here we generate genome sequences from 446 geographically diverse accessions of the wild rice species Oryza rufipogon, the immediate ancestral progenitor of cultivated rice, and from 1,083 cultivated indica and japonica varieties to construct a comprehensive map of rice genome variation. In the search for signatures of selection, we identify 55 selective sweeps that have occurred during domestication. In-depth analyses of the domestication sweeps and genome-wide patterns reveal that Oryza sativa japonica rice was first domesticated from a specific population of O. rufipogon around the middle area of the Pearl River in southern China, and that Oryza sativa indica rice was subsequently developed from crosses between japonica rice and local wild rice as the initial cultivars spread into South East and South Asia. The domestication-associated traits are analysed through high-resolution genetic mapping. This study provides an important resource for rice breeding and an effective genomics approach for crop domestication research. PMID:23034647

  12. The Rice Genome Knowledgebase (RGKbase): an annotation database for rice comparative genomics and evolutionary biology

    PubMed Central

    Wang, Dapeng; Xia, Yan; Li, Xinna; Hou, Lixia; Yu, Jun

    2013-01-01

    Over the past 10 years, genomes of cultivated rice cultivars and their wild counterparts have been sequenced although most efforts are focused on genome assembly and annotation of two major cultivated rice (Oryza sativa L.) subspecies, 93-11 (indica) and Nipponbare (japonica). To integrate information from genome assemblies and annotations for better analysis and application, we now introduce a comparative rice genome database, the Rice Genome Knowledgebase (RGKbase, http://rgkbase.big.ac.cn/RGKbase/). RGKbase is built to have three major components: (i) integrated data curation for rice genomics and molecular biology, which includes genome sequence assemblies, transcriptomic and epigenomic data, genetic variations, quantitative trait loci (QTLs) and the relevant literature; (ii) User-friendly viewers, such as Gbrowse, GeneBrowse and Circos, for genome annotations and evolutionary dynamics and (iii) Bioinformatic tools for compositional and synteny analyses, gene family classifications, gene ontology terms and pathways and gene co-expression networks. RGKbase current includes data from five rice cultivars and species: Nipponbare (japonica), 93-11 (indica), PA64s (indica), the African rice (Oryza glaberrima) and a wild rice species (Oryza brachyantha). We are also constantly introducing new datasets from variety of public efforts, such as two recent releases—sequence data from ∼1000 rice varieties, which are mapped into the reference genome, yielding ample high-quality single-nucleotide polymorphisms and insertions–deletions. PMID:23193278

  13. 40 CFR 406.60 - Applicability; description of the parboiled rice processing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... parboiled rice processing subcategory. 406.60 Section 406.60 Protection of Environment ENVIRONMENTAL... Rice Processing Subcategory § 406.60 Applicability; description of the parboiled rice processing... rice is cleaned, cooked and dried before being milled....

  14. 40 CFR 406.60 - Applicability; description of the parboiled rice processing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... parboiled rice processing subcategory. 406.60 Section 406.60 Protection of Environment ENVIRONMENTAL... Rice Processing Subcategory § 406.60 Applicability; description of the parboiled rice processing... rice is cleaned, cooked and dried before being milled....

  15. 40 CFR 406.60 - Applicability; description of the parboiled rice processing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... parboiled rice processing subcategory. 406.60 Section 406.60 Protection of Environment ENVIRONMENTAL... Rice Processing Subcategory § 406.60 Applicability; description of the parboiled rice processing... rice is cleaned, cooked and dried before being milled....

  16. 40 CFR 406.60 - Applicability; description of the parboiled rice processing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... parboiled rice processing subcategory. 406.60 Section 406.60 Protection of Environment ENVIRONMENTAL... Rice Processing Subcategory § 406.60 Applicability; description of the parboiled rice processing... rice is cleaned, cooked and dried before being milled....

  17. 40 CFR 406.60 - Applicability; description of the parboiled rice processing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... parboiled rice processing subcategory. 406.60 Section 406.60 Protection of Environment ENVIRONMENTAL... Rice Processing Subcategory § 406.60 Applicability; description of the parboiled rice processing... rice is cleaned, cooked and dried before being milled....

  18. Characterization of cadmium-resistant bacteria and their potential for reducing accumulation of cadmium in rice grains.

    PubMed

    Lin, Xiaoyan; Mou, Renxiang; Cao, Zhaoyun; Xu, Ping; Wu, Xiaoliang; Zhu, Zhiwei; Chen, Mingxue

    2016-11-01

    Cadmium (Cd) pollution is a serious widespread environmental problem that not only destroys the microbial ecology of soil and decreases crop production, but also poses a serious risk to human health. Many methods have been used for the remediation of Cd pollution but none of these is totally satisfactory. Microbial remediation strategies have attracted increasing interest since they are environmentally friendly and cost-effective. In the present study, three Cd-resistant bacteria were isolated and evaluated for potential application in Cd bioremediation. Based on their morphological, physiological and biochemical characteristics, together with 16S rDNA gene sequence analyses, bacteria were identified as Stenotrophomonas acidaminiphila (2#), Pseudomonas aeruginosa (9#) and Delftia tsuruhatensis (12#). Pseudomonas aeruginosa showed very high tolerance to metals, especially Cd (2200mg/L), Zn (1800mg/L) and Pb (1200mg/L), and is thought to be a multi-metal-resistant bacterium. Pseudomonas aeruginosa was also sensitive to 13 different antibiotics. The effects of the bacterial strains on the growth of rice plants and their ability to reduce Cd accumulation from Cd-contaminated soils in pot experiments were also evaluated. For Oryza sativa L. A grown in contaminated soil (3mg/kg Cd), the accumulation of Cd was decreased by 31.2 and 25.5% in brown rice and polished rice, respectively, by strain 9#; Pseudomonas aeruginosa was more effective in reducing Cd accumulation in rice grains than a mixture of strains. For Oryza sativa L. B, a mixture of strains acting synergistically was more effective than a single strain in reducing Cd accumulation; treatment with mixed strains (strains+3mg/kg Cd) resulted in 41.3, 35.9, and 32.6% reductions in Cd accumulation in unhulled rice, brown rice and polished rice, respectively. Although different results were obtained for two rice varieties, it can still be concluded that Cd-resistant bacteria are suitable for reducing Cd accumulation in

  19. Effects of aleurone layer on rice cooking: A histological investigation.

    PubMed

    Wu, Jianyong; Chen, Jun; Liu, Wei; Liu, Chengmei; Zhong, Yejun; Luo, Dawen; Li, Zhongqiang; Guo, Xiaojuan

    2016-01-15

    Understanding how aleurone layer (AL) affects rice cooking behaviour is important for rice processing. Individual effects of AL on rice cooking behaviour were evaluated and histological characters of AL before and after cooking were investigated. AL slightly affected rice cooking quality (optimum cooking time, water absorption, volume expansion ratio and total solids loss) while remarkably affected rice texture (hardness and adhesiveness) and peak viscosity. Histological investigation showed that channels were formed in AL during cooking. The channels facilitated the penetration of water, which could explain why AL exhibited slight effects on rice cooking quality. In addition, thick cell walls and thermally stable aleurone grains were widely distributed in AL. Leached components accumulated on them and formed a reinforced coated film on rice surface during cooking, which may be a possible mechanism accounting for the remarkable effect of AL on rice texture. Histological characters of AL are closely related with rice cooking behaviour. PMID:26258698

  20. Interaction between C 4 barnyard grass and C 3 upland rice under elevated CO 2: Impact of mycorrhizae

    NASA Astrophysics Data System (ADS)

    Tang, Jianjun; Xu, Liming; Chen, Xin; Hu, Shuijin

    2009-03-01

    Atmospheric CO 2 enrichment may impact arbuscular mycorrhizae (AM) development and function, which could have subsequent effects on host plant species interactions by differentially affecting plant nutrient acquisition. However, direct evidence illustrating this scenario is limited. We examined how elevated CO 2 affects plant growth and whether mycorrhizae mediate interactions between C 4 barnyard grass ( Echinochloa crusgalli (L.) Beauv.) and C 3 upland rice ( Oryza sativa L.) in a low nutrient soil. The monocultures and combinations with or without mycorrhizal inoculation were grown at ambient (400 ± 20 μmol mol -1) and elevated CO 2 (700 ± 20 μmol mol -1) levels. The 15N isotope tracer was introduced to quantify the mycorrhizally mediated N acquisition of plants. Elevated CO 2 stimulated the growth of C 3 upland rice but not that of C 4 barnyard grass under monoculture. Elevated CO 2 also increased mycorrhizal colonization of C 4 barnyard grass but did not affect mycorrhizal colonization of C 3 upland rice. Mycorrhizal inoculation increased the shoot biomass ratio of C 4 barnyard grass to C 3 upland rice under both CO 2 concentrations but had a greater impact under the elevated than ambient CO 2 level. Mycorrhizae decreased relative interaction index (RII) of C 3 plants under both ambient and elevated CO 2, but mycorrhizae increased RII of C 4 plants only under elevated CO 2. Elevated CO 2 and mycorrhizal inoculation enhanced 15N and total N and P uptake of C 4 barnyard grass in mixture but had no effects on N and P acquisition of C 3 upland rice, thus altering the distribution of N and P between the species in mixture. These results implied that CO 2 stimulation of mycorrhizae and their nutrient acquisition may impact competitive interaction of C 4 barnyard grass and C 3 upland rice under future CO 2 scenarios.

  1. Nuclear and Chloroplast DNA Variation Provides Insights into Population Structure and Multiple Origin of Native Aromatic Rices of Odisha, India.

    PubMed

    Roy, Pritesh Sundar; Rao, Gundimeda Jwala Narasimha; Jena, Sudipta; Samal, Rashmita; Patnaik, Ashok; Patnaik, Sasank Sekhar Chyau; Jambhulkar, Nitiprasad Namdeorao; Sharma, Srigopal; Mohapatra, Trilochan

    2016-01-01

    A large number of short grain aromatic rice suited to the agro-climatic conditions and local preferences are grown in niche areas of different parts of India and their diversity is evolved over centuries as a result of selection by traditional farmers. Systematic characterization of these specialty rices has not been attempted. An effort was made to characterize 126 aromatic short grain rice landraces, collected from 19 different districts in the State of Odisha, from eastern India. High level of variation for grain quality and agronomic traits among these aromatic rices was observed and genotypes having desirable phenotypic traits like erect flag leaf, thick culm, compact and dense panicles, short plant stature, early duration, superior yield and grain quality traits were identified. A total of 24 SSR markers corresponding to the hyper variable regions of rice chromosomes were used to understand the genetic diversity and to establish the genetic relationship among the aromatic short grain rice landraces at nuclear genome level. SSR analysis of 126 genotypes from Odisha and 10 genotypes from other states revealed 110 alleles with an average of 4.583 and the Nei's genetic diversity value (He) was in the range of 0.034-0.880 revealing two sub-populations SP 1 (membership percentage-27.1%) and SP 2 (72.9%). At the organelle genomic level for the C/A repeats in PS1D sequence of chloroplasts, eight different plastid sub types and 33 haplotypes were detected. The japonica (Nipponbare) subtype (6C7A) was detected in 100 genotypes followed by O. rufipogon (KF428978) subtype (6C6A) in 13 genotypes while indica (93-11) sub type (8C8A) was seen in 14 genotypes. The tree constructed based on haplotypes suggests that short grain aromatic landraces might have independent origin of these plastid subtypes. Notably a wide range of diversity was observed among these landraces cultivated in different parts confined to the State of Odisha. PMID:27598392

  2. Investigation of rice proteomic change in response to microgravity

    NASA Astrophysics Data System (ADS)

    Sun, Weining

    Gravity is one of the environmental factors that control development and growth of plants. Plant cells which are not part of specialized tissues such as the root columella can also sense gravity. Space environment, such as space shuttle missions, space labortories and space stations, etc. provide unique oppotunities to study the microgravity response of plant. During the Shenzhou 8 mission in November 2011, we cultured rice cali on the spaceship and the samples were fixed 4 days after launch. The flying samples in the static position (micro g, mug) and in the centrifuge which provide 1 g force to mimic the 1 g gravity in space, were recovered and the proteome changes were analyzed by iTRAQ. In total, 4840 proteins were identified, including 2085 proteins with function annotation by GO analysis. 431 proteins were changed >1.5 fold in space µg /ground group, including 179 up-regulated proteins and down-regulated 252 proteins. 321 proteins were changed >1.5 fold in space muµg / space 1 g group, among which 205 proteins were the same differentially expressed proteins responsive to microgravity. Enrichment of the differnetially expressed proteins by GO analysis showed that the ARF GTPase activity regulation proteins were enriched when compared the space µg with space 1 g sample, whereas the nucleic acid binding and DNA damage repairing proteins were enriched when compared the space µg and ground sample. Microscopic comparison of the rice cali showed that the space grown cells are more uniformed in size and proliferation, suggesting that cell proliferation pattern was changed in space microgravity conditions.

  3. President Kennedy's Speech at Rice University

    NASA Technical Reports Server (NTRS)

    1988-01-01

    This video tape presents unedited film footage of President John F. Kennedy's speech at Rice University, Houston, Texas, September 12, 1962. The speech expresses the commitment of the United States to landing an astronaut on the Moon.

  4. Arsenic in rice: a cause for concern.

    PubMed

    Hojsak, Iva; Braegger, Christian; Bronsky, Jiri; Campoy, Cristina; Colomb, Virginie; Decsi, Tamas; Domellöf, Magnus; Fewtrell, Mary; Mis, Nataša Fidler; Mihatsch, Walter; Molgaard, Christian; van Goudoever, Johannes

    2015-01-01

    Inorganic arsenic intake is likely to affect long-term health. High concentrations are found in some rice-based foods and drinks widely used in infants and young children. In order to reduce exposure, we recommend avoidance of rice drinks for infants and young children. For all of the rice products, strict regulation should be enforced regarding arsenic content. Moreover, infants and young children should consume a balanced diet including a variety of grains as carbohydrate sources. Although rice protein-based infant formulas are an option for infants with cows' milk protein allergy, the inorganic arsenic content should be declared and the potential risks should be considered when using these products. PMID:25536328

  5. Direct and reverse pollen-mediated gene flow between GM rice and red rice weed

    PubMed Central

    Serrat, X.; Esteban, R.; Peñas, G.; Català, M. M.; Melé, E.; Messeguer, J.

    2013-01-01

    Potential risks of genetically modified (GM) crops must be identified before their commercialization, as happens with all new technologies. One of the major concerns is the proper risk assessment of adventitious presence of transgenic material in rice fields due to cross-pollination. Several studies have been conducted in order to quantify pollen-mediated gene flow from transgenic rice (Oryza sativa) to both conventional rice and red rice weed (O. sativa f. spontanea) under field conditions. Some of these studies reported GM pollen-donor rice transferring GM traits to red rice. However, gene flow also occurs in the opposite direction, in a phenomenon that we have called reverse gene flow, resulting in transgenic seeds that have incorporated the traits of wild red rice. We quantified reverse gene flow using material from two field trials. A molecular analysis based on amplified fragment length polymorphisms was carried out, being complemented with a phenotypic identification of red rice traits. In both field trials, the reverse gene flow detected was greater than the direct gene flow. The rate of direct gene flow varied according to the relative proportions of the donor (GM rice) and receptor (red rice) plants and was influenced by wind direction. The ecological impact of reverse gene flow is limited in comparison with that of direct gene flow because non-shattered and non-dormant seeds would be obtained in the first generation. Hybrid seed would remain in the spike and therefore most of it would be removed during harvesting. Nevertheless, this phenomenon must be considered in fields used for elite seed production and in developing countries where farmers often keep some seed for planting the following year. In these cases, there is a higher risk of GM red rice weed infestation increasing from year to year and therefore a proper monitoring plan needs to be established.

  6. Evolutionary insights into the origins of weediness in U.S. red rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weedy red rice is a widespread, economically challenging problem in Southern U.S. rice fields. The two major U.S. red rice types, strawhull and blackhull, are thought to have arisen independently from Asian rice populations in the distant past. Red rice is a weedy relative of rice, a genomic model...

  7. An update on the use of rice in value-added food products.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because of the huge quantity of rice produced annually, milled-rice co-products; such as, rice flour, rice bran, rice wax, and rice hull are plentiful and readily available. These co-products could be valuable sources of food ingredients, but they have been vastly under-utilized. This is a report ...

  8. Transfer of herbicide-resistant gene to weedy rice populations and its implications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice diversity in terms of phenology, sexual compatibility with cultivated rice, and the wide window of rice planting time can affect the rate of herbicide-resistant gene transfer from rice to RR. Experiments were conducted to a) determine the effect of red rice, rice cultivar, and planting date...

  9. Introgression of resistance-conferring ALS mutations in herbicide-resistant weedy rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weedy red rice (Oryza sativa) competes aggressively with rice, reducing yields and grain quality. Clearfield™ rice, a nontransgenic, herbicide-resistant (HR) rice introduced in 2002 to control weedy rice, has resulted in some ALS-resistant weedy rice apparently due to gene flow. Studies were conduct...

  10. Genetic diversity of weedy red rice (Oryza sativa) in Arkansas, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weedy red rice (Oryza sativa L.) is a problematic weed in rice. About 50% of US rice is produced in Arkansas and 60% of these fields have some red rice infestation. Red rice populations are morphologically and phenologically diverse. We hypothesize that red rice in Arkansas has high genetic diversit...

  11. RED RICE DIVERSITY AND PLANTING DATE EFFECTS ON RISK OF GENE FLOW

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice (Oryza sativa L.) is a problematic weed in rice production worldwide. Red rice control is difficult with conventional herbicides due to its similar biology and physiology as cultivated rice. However, herbicide-resistant (HR) rice provides a valuable tool for red rice management, but with a ...

  12. Value-added uses of co-products from the milling of rice.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to the polished whole white rice, various co-products, including rice bran and broken rice, are generated during the milling of rice. In spite of plentiful supply and high nutrition, rice bran, and to a lesser extent, broken rice kernels are under-priced and under-utilized. The present ...

  13. Phytotoxicity and oxidative stress effect of 1-octyl-3-methylimidazolium chloride ionic liquid on rice seedlings.

    PubMed

    Liu, Huijun; Zhang, Shuxian; Hu, Xiaona; Chen, Caidong

    2013-10-01

    The effects of the ionic liquid 1-octyl-3-methylimidazolium chloride ([OMIM]Cl) was studied in hydroponically grown rice seedlings. Observed effects included increased root length and weight at concentrations of 0.1 mg/L [OMIM]Cl, however, as concentrations increased a reversed response was observed where roots and stems grew shorter and the weight decreased. The inhibitory concentration 50 (IC50,5d) values for root length and stem length were 0.59 mg/L and 0.70 mg/L, respectively. The Hill reaction activity and root system activity in [OMIM]Cl-treated rice seedlings were observed to be lower than the controls, however, root membrane permeability increased. The antioxidant enzyme activity in roots decreased, while in leaves there was an initial stimulation followed by a decrease. Malondialdehyde (MDA) content was found to be greater in seedlings subjected to [OMIM]Cl treatment. The cellular structures, such as chloroplasts, mitochondria and rough endoplasmic reticulum in rice root and leaf cells were affected at concentrations of 0.6 mg/L [OMIM]Cl. PMID:23877038

  14. Different bacterial populations associated with the roots and rhizosphere of rice incorporate plant-derived carbon.

    PubMed

    Hernández, Marcela; Dumont, Marc G; Yuan, Quan; Conrad, Ralf

    2015-03-01

    Microorganisms associated with the roots of plants have an important function in plant growth and in soil carbon sequestration. Rice cultivation is the second largest anthropogenic source of atmospheric CH4, which is a significant greenhouse gas. Up to 60% of fixed carbon formed by photosynthesis in plants is transported below ground, much of it as root exudates that are consumed by microorganisms. A stable isotope probing (SIP) approach was used to identify microorganisms using plant carbon in association with the roots and rhizosphere of rice plants. Rice plants grown in Italian paddy soil were labeled with (13)CO2 for 10 days. RNA was extracted from root material and rhizosphere soil and subjected to cesium gradient centrifugation followed by 16S rRNA amplicon pyrosequencing to identify microorganisms enriched with (13)C. Thirty operational taxonomic units (OTUs) were labeled and mostly corresponded to Proteobacteria (13 OTUs) and Verrucomicrobia (8 OTUs). These OTUs were affiliated with the Alphaproteobacteria, Betaproteobacteria, and Deltaproteobacteria classes of Proteobacteria and the "Spartobacteria" and Opitutae classes of Verrucomicrobia. In general, different bacterial groups were labeled in the root and rhizosphere, reflecting different physicochemical characteristics of these locations. The labeled OTUs in the root compartment corresponded to a greater proportion of the 16S rRNA sequences (∼20%) than did those in the rhizosphere (∼4%), indicating that a proportion of the active microbial community on the roots greater than that in the rhizosphere incorporated plant-derived carbon within the time frame of the experiment. PMID:25616793

  15. Formation of Organically Bound Deuterium at Each Growing Stage of Rice

    SciTech Connect

    Atarashi-Andoh, Mariko; Kumakura, Yasuharu; Amano, Hikaru; Fukui, Masami

    2005-07-15

    Potted rice plants were exposed to deuterated water vapor, as a substitute of tritium, for 4 hours at five different times during the grain-ripening period to estimate the influence of the growth stage on the formation and retention of organically bound deuterium (OBD) in rice. The plants were grown outside before and after the exposure experiments and were exposed to deuterated water vapor in a laboratory in a small chamber equipped with controllers of temperature, humidity and light intensity. Deuterium concentrations in free water and organic matter in rice leaves, stems and grains were investigated up to the harvest time. The deuterium in free water in the grains remained for a longer time after the end of exposure than in the leaves and stems. The mass of OBD in grain at harvest showed the highest value when the exposure was carried out in the early stage of the ripening period. When the exposure was carried out after 26 days from the heading, the increase of OBD in the grain was small.

  16. Rice Root Architectural Plasticity Traits and Genetic Regions for Adaptability to Variable Cultivation and Stress Conditions.

    PubMed

    Sandhu, Nitika; Raman, K Anitha; Torres, Rolando O; Audebert, Alain; Dardou, Audrey; Kumar, Arvind; Henry, Amelia

    2016-08-01

    Future rice (Oryza sativa) crops will likely experience a range of growth conditions, and root architectural plasticity will be an important characteristic to confer adaptability across variable environments. In this study, the relationship between root architectural plasticity and adaptability (i.e. yield stability) was evaluated in two traditional × improved rice populations (Aus 276 × MTU1010 and Kali Aus × MTU1010). Forty contrasting genotypes were grown in direct-seeded upland and transplanted lowland conditions with drought and drought + rewatered stress treatments in lysimeter and field studies and a low-phosphorus stress treatment in a Rhizoscope study. Relationships among root architectural plasticity for root dry weight, root length density, and percentage lateral roots with yield stability were identified. Selected genotypes that showed high yield stability also showed a high degree of root plasticity in response to both drought and low phosphorus. The two populations varied in the soil depth effect on root architectural plasticity traits, none of which resulted in reduced grain yield. Root architectural plasticity traits were related to 13 (Aus 276 population) and 21 (Kali Aus population) genetic loci, which were contributed by both the traditional donor parents and MTU1010. Three genomic loci were identified as hot spots with multiple root architectural plasticity traits in both populations, and one locus for both root architectural plasticity and grain yield was detected. These results suggest an important role of root architectural plasticity across future rice crop conditions and provide a starting point for marker-assisted selection for plasticity. PMID:27342311

  17. Leaf Lateral Asymmetry in Morphological and Physiological Traits of Rice Plant

    PubMed Central

    Yuan, Shen; Li, Yong; Peng, Shaobing

    2015-01-01

    Leaf lateral asymmetry in width and thickness has been reported previously in rice. However, the differences between the wide and narrow sides of leaf blade in other leaf morphological and physiological traits were not known. This study was conducted to quantify leaf lateral asymmetry in leaf width, leaf thickness, specific leaf weight (SLW), leaf nitrogen (N) concentration based on dry weight (Nw) and leaf area (Na), and chlorophyll meter reading (SPAD). Leaf morphological and physiological traits of the two lateral halves of the top three leaves at heading stage were measured on 23 rice varieties grown in three growing seasons in two locations. Leaf lateral asymmetry was observed in leaf width, leaf thickness, Nw, Na, and SPAD, but not in SLW. On average, the leaf width of the wide side was about 17% higher than that of the narrow side. The wide side had higher leaf thickness than the narrow side whereas the narrow side had higher Nw, Na, and SPAD than the wide side. We conclude that the narrow side of leaf blade maintained higher leaf N status than the wide side based on all N-related parameters, which implies a possibility of leaf lateral asymmetry in photosynthetic rate in rice plant. PMID:26053267

  18. Leaf Lateral Asymmetry in Morphological and Physiological Traits of Rice Plant.

    PubMed

    Yuan, Shen; Li, Yong; Peng, Shaobing

    2015-01-01

    Leaf lateral asymmetry in width and thickness has been reported previously in rice. However, the differences between the wide and narrow sides of leaf blade in other leaf morphological and physiological traits were not known. This study was conducted to quantify leaf lateral asymmetry in leaf width, leaf thickness, specific leaf weight (SLW), leaf nitrogen (N) concentration based on dry weight (Nw) and leaf area (Na), and chlorophyll meter reading (SPAD). Leaf morphological and physiological traits of the two lateral halves of the top three leaves at heading stage were measured on 23 rice varieties grown in three growing seasons in two locations. Leaf lateral asymmetry was observed in leaf width, leaf thickness, Nw, Na, and SPAD, but not in SLW. On average, the leaf width of the wide side was about 17% higher than that of the narrow side. The wide side had higher leaf thickness than the narrow side whereas the narrow side had higher Nw, Na, and SPAD than the wide side. We conclude that the narrow side of leaf blade maintained higher leaf N status than the wide side based on all N-related parameters, which implies a possibility of leaf lateral asymmetry in photosynthetic rate in rice plant. PMID:26053267

  19. Different Bacterial Populations Associated with the Roots and Rhizosphere of Rice Incorporate Plant-Derived Carbon

    PubMed Central

    Hernández, Marcela; Yuan, Quan; Conrad, Ralf

    2015-01-01

    Microorganisms associated with the roots of plants have an important function in plant growth and in soil carbon sequestration. Rice cultivation is the second largest anthropogenic source of atmospheric CH4, which is a significant greenhouse gas. Up to 60% of fixed carbon formed by photosynthesis in plants is transported below ground, much of it as root exudates that are consumed by microorganisms. A stable isotope probing (SIP) approach was used to identify microorganisms using plant carbon in association with the roots and rhizosphere of rice plants. Rice plants grown in Italian paddy soil were labeled with 13CO2 for 10 days. RNA was extracted from root material and rhizosphere soil and subjected to cesium gradient centrifugation followed by 16S rRNA amplicon pyrosequencing to identify microorganisms enriched with 13C. Thirty operational taxonomic units (OTUs) were labeled and mostly corresponded to Proteobacteria (13 OTUs) and Verrucomicrobia (8 OTUs). These OTUs were affiliated with the Alphaproteobacteria, Betaproteobacteria, and Deltaproteobacteria classes of Proteobacteria and the “Spartobacteria” and Opitutae classes of Verrucomicrobia. In general, different bacterial groups were labeled in the root and rhizosphere, reflecting different physicochemical characteristics of these locations. The labeled OTUs in the root compartment corresponded to a greater proportion of the 16S rRNA sequences (∼20%) than did those in the rhizosphere (∼4%), indicating that a proportion of the active microbial community on the roots greater than that in the rhizosphere incorporated plant-derived carbon within the time frame of the experiment. PMID:25616793

  20. The effect of the external medium on the gravitropic curvature of rice (Oryza sativa, Poaceae) roots

    NASA Technical Reports Server (NTRS)

    Staves, M. P.; Wayne, R.; Leopold, A. C.

    1997-01-01

    The roots of rice seedlings, growing in artificial pond water, exhibit robust gravitropic curvature when placed perpendicular to the vector of gravity. To determine whether the statolith theory (in which intracellular sedimenting particles are responsible for gravity sensing) or the gravitational pressure theory (in which the entire protoplast acts as the gravity sensor) best accounts for gravity sensing in rice roots, we changed the physical properties of the external medium with impermeant solutes and examined the effect on gravitropism. As the density of the external medium is increased, the rate of gravitropic curvature decreases. The decrease in the rate of gravicurvature cannot be attributed to an inhibition of growth, since rice roots grown in 100 Osm/m3 (0.248 MPa) solutions of different densities all support the same root growth rate but inhibit gravicurvature increasingly with increasing density. By contrast, the sedimentation rate of amyloplasts in the columella cells is unaffected by the external density. These results are consistent with the gravitational pressure theory of gravity sensing, but cannot be explained by the statolith theory.

  1. Mycotoxin production on rice, pulses and oilseeds

    NASA Astrophysics Data System (ADS)

    Begum, Fouzia; Samajpati, N.

    Mycotoxin-producing fungi were isolated from contaminated grains of rice, pulses and oilseeds sold in the local markets of Calcutta for human consumption. It was found that aflatoxin B1 was produced by Aspergillus flavus and Aspergillus parasiticus, aflatoxin G1 by A. flavus, ochratoxin by Aspergillus ochraceous, sterigmatocystin by Aspergillus japonicus and citrinin by Penicillium citrinum. Aflatoxin B1 (333-10416μg/kg) was produced by Aspergillus spp. in rice, pulses and oilseeds.

  2. Impact of six transgenic Bacillus thuringiensis rice lines on four nontarget thrips species attacking rice panicles in the paddy field.

    PubMed

    Akhtar, Z R; Tian, J C; Chen, Y; Fang, Q; Hu, C; Peng, Y F; Ye, G Y

    2013-02-01

    As a key component of ecological risk assessments, nontarget effects of Bacillus thuringiensis (Bt) rice have been tested under laboratory and field conditions for various organisms. A 2-yr field experiment was conducted to observe the nontarget effects of six transgenic rice lines (expressing the Cry1Ab or fused protein of Cry1Ab and Cry1Ac) on four nontarget thrips species including Frankliniella intonsa (Trybom), F. tenuicornis (Uzel), Haplothrips aculeatus (F.), and H. tritici (Kurd), as compared with their rice parental control lines. Two sampling methods including the beat plate and plastic bag method were used to monitor the population densities of the four thrips species for 2 yr. The results showed that the seasonal average densities of four tested thrips species in Bt rice plots were significantly lower than or very similar to those in the non-Bt rice plots depending on rice genotypes, sampling methods, and years. Among all six tested Bt rice lines, transgenic B1 and KMD2 lines suppressed the population of these tested thrips species the most. Our results indicate that the tested Bt rice lines are unlikely to result in high population pressure of thrips species in comparison with non-Bt rice. In some cases, Bt rice lines could significantly suppress thrips populations in the rice ecosystem. In addition, compatibility of Bt rice, with rice host plant resistance to nontarget sucking pests is also discussed within an overall integrated pest management program for rice. PMID:23339799

  3. Effect of gamma irradiation on rice and its food products

    NASA Astrophysics Data System (ADS)

    Sung, Wen-Chieh

    2005-07-01

    Two milled indica rice varieties were exposed to gamma radiation with doses ranging from 0 to 1.0 kGy. The effects of gamma irradiation on rice flour pasting properties and the qualities of its food product, rice curd, were compared to the effects of storage. A dose of 1 kGy can decrease the flour paste viscosity and tenderize the texture of the rice curd to similar levels as those obtained after 12 months of storage. It was thus shown that gamma irradiation could shorten the indica rice aging time and improve the processing stability and quality of rice products.

  4. The structure of rice weevil pectin methylesterase

    PubMed Central

    Teller, David C.; Behnke, Craig A.; Pappan, Kirk; Shen, Zicheng; Reese, John C.; Reeck, Gerald R.; Stenkamp, Ronald E.

    2014-01-01

    Rice weevils (Sitophilus oryzae) use a pectin methylesterase (EC 3.1.1.11), along with other enzymes, to digest cell walls in cereal grains. The enzyme is a right-handed β-helix protein, but is circularly permuted relative to plant and bacterial pectin methylesterases, as shown by the crystal structure determination reported here. This is the first structure of an animal pectin methylesterase. Diffraction data were collected to 1.8 Å resolution some time ago for this crystal form, but structure solution required the use of molecular-replacement techniques that have been developed and similar structures that have been deposited in the last 15 years. Comparison of the structure of the rice weevil pectin methylesterase with that from Dickeya dandantii (formerly Erwinia chrysanthemi) indicates that the reaction mechanisms are the same for the insect, plant and bacterial pectin methylesterases. The similarity of the structure of the rice weevil enzyme to the Escherichia coli lipoprotein YbhC suggests that the evolutionary origin of the rice weevil enzyme was a bacterial lipoprotein, the gene for which was transferred to a primitive ancestor of modern weevils and other Curculionidae. Structural comparison of the rice weevil pectin methylesterase with plant and bacterial enzymes demonstrates that the rice weevil protein is circularly permuted relative to the plant and bacterial molecules. PMID:25372813

  5. Hydrocolloid sour taste control in pasteurized rice.

    PubMed

    Azanza, Maria Patricia V

    2014-12-01

    The effects of kappa (κ)-carrageenan and carboxymethyl cellulose (CMC) in controlling the sourness intensity perception of added acetic, citric, and tartaric acids in solutions for steeping and cooking of rice intended for pasteurization were determined. The rank order of added acids (0.10 and 0.20 % w/v, pH 4.00) in the initial development of acidified hydrocolloid solutions was: acetic > citric > tartaric. The final rice acidification protocols included steeping and cooking of Japonica rice cultivar Kanto in tartaric-acidified hydrocolloid solutions of κ-carrageenan and CMC (0.30 % w/v, 50 ± 2 °C for 1 h) at pH 2.75 and 2.90, respectively. The acidified cooked rice in pouches were pasteurized in boiling water (100 °C) to reach 95 °C for 5 min. The pasteurized products were categorized under acidified foods with final Aw < 0.85 and pH < 4.00. No perceivable sour tastes from 1 to 12 week storage at 28 ± 2 °C were noted in the pasteurized rice products. The shelf-stable pasteurized products were described as white, translucent, with distinct natural rice aroma and flavor, firm, and slightly elastic mouth and hand feel. PMID:25477672

  6. Characterization of Rice Husk for Cyclone Gasifier

    NASA Astrophysics Data System (ADS)

    Mohamad Yusof, I.; Farid, N. A.; Zainal, Z. A.; Azman, M.

    The characterization of rice husk from local rice mills has been studied and evaluated to determine its potential utilization as a biomass fuel for a cyclone gasifier. The raw rice husk was pre-treated throughout a grinding process into smaller sizes of particles which is within a range of 0.4 to 1 mm and the sample of ground rice husk was analyzed for its fuel characteristics. The result of proximate analysis shows that the ground rice husk with size distribution within 0.4 to 1 mm contains 13.4% of fixed carbon, 62.95% of volatile matter and 18.5% of ash on dry basis. The moisture content of the sample was measured and determined as 10.4% (wet basis) and the calorific value was found to be approximately 14.8 MJ kg-1 with bulk density of 91.46 kg m-3. The result of ultimate analysis validates both ash and moisture content which are found to be 18.15 and 10.4%, respectively. Other elemental compositions determined by the ultimate analysis are carbon (37.9%), hydrogen (5.2%), nitrogen (0.14%), sulfur (0.61%) and oxygen (27.7% by difference). The study has identified that the fuel characteristics of the ground rice husk is comparable with other types of biomass and thus, making it another potential source of fuel for the cyclone gasification system.

  7. Altered cell wall properties are responsible for ammonium-reduced aluminium accumulation in rice roots.

    PubMed

    Wang, Wei; Zhao, Xue Qiang; Chen, Rong Fu; Dong, Xiao Ying; Lan, Ping; Ma, Jian Feng; Shen, Ren Fang

    2015-07-01

    The phytotoxicity of aluminium (Al) ions can be alleviated by ammonium (NH4(+)) in rice and this effect has been attributed to the decreased Al accumulation in the roots. Here, the effects of different nitrogen forms on cell wall properties were compared in two rice cultivars differing in Al tolerance. An in vitro Al-binding assay revealed that neither NH4(+) nor NO3(-) altered the Al-binding capacity of cell walls, which were extracted from plants not previously exposed to N sources. However, cell walls extracted from NH4(+)-supplied roots displayed lower Al-binding capacity than those from NO3(-)-supplied roots when grown in non-buffered solutions. Fourier-transform infrared microspectroscopy analysis revealed that, compared with NO3(-)-supplied roots, NH4(+)-supplied roots possessed fewer Al-binding groups (-OH and COO-) and lower contents of pectin and hemicellulose. However, when grown in pH-buffered solutions, these differences in the cell wall properties were not observed. Further analysis showed that the Al-binding capacity and properties of cell walls were also altered by pHs alone. Taken together, our results indicate that the NH4(+)-reduced Al accumulation was attributed to the altered cell wall properties triggered by pH decrease due to NH4(+) uptake rather than direct competition for the cell wall binding sites between Al(3+) and NH4(+). PMID:25444246

  8. Phosphoenolpyruvate carboxylase intrinsically located in the chloroplast of rice plays a crucial role in ammonium assimilation

    PubMed Central

    Masumoto, Chisato; Miyazawa, Shin-Ichi; Ohkawa, Hiroshi; Fukuda, Takuya; Taniguchi, Yojiro; Murayama, Seiji; Kusano, Miyako; Saito, Kazuki; Fukayama, Hiroshi; Miyao, Mitsue

    2010-01-01

    Phosphoenolpyruvate carboxylase (PEPC) is a key enzyme of primary metabolism in bacteria, algae, and vascular plants, and is believed to be cytosolic. Here we show that rice (Oryza sativa L.) has a plant-type PEPC, Osppc4, that is targeted to the chloroplast. Osppc4 was expressed in all organs tested and showed high expression in the leaves. Its expression in the leaves was confined to mesophyll cells, and Osppc4 accounted for approximately one-third of total PEPC protein in the leaf blade. Recombinant Osppc4 was active in the PEPC reaction, showing Vmax comparable to cytosolic isozymes. Knockdown of Osppc4 expression by the RNAi technique resulted in stunting at the vegetative stage, which was much more marked when rice plants were grown with ammonium than with nitrate as the nitrogen source. Comparison of leaf metabolomes of ammonium-grown plants suggested that the knockdown suppressed ammonium assimilation and subsequent amino acid synthesis by reducing levels of organic acids, which are carbon skeleton donors for these processes. We also identified the chloroplastic PEPC gene in other Oryza species, all of which are adapted to waterlogged soil where the major nitrogen source is ammonium. This suggests that, in addition to glycolysis, the genus Oryza has a unique route to provide organic acids for ammonium assimilation that involves a chloroplastic PEPC, and that this route is crucial for growth with ammonium. This work provides evidence for diversity of primary ammonium assimilation in the leaves of vascular plants. PMID:20194759

  9. Activities of nitrate reductase and glutamine synthetase in rice seedlings during cyanide metabolism.

    PubMed

    Yu, Xiao-Zhang; Zhang, Fu-Zhong

    2012-07-30

    A study was conducted to investigate activities of nitrate reductase (NR) and glutamine synthetase (GS) in plants during cyanide metabolism. Young rice seedlings (Oryza sativa L. cv. XZX 45) were grown in the nutrient solutions containing KNO(3) or NH(4)Cl and treated with free cyanide (KCN). Cyanide in solutions and in plant materials was analyzed to estimate the phyto-assimilation potential. Activities of NR and GS in different parts of rice seedlings were assayed in vivo. Seedlings grown on NH(4)(+) showed significantly higher relative growth rate than those on NO(3)(-) (p<0.05) in the presence of exogenous cyanide. The metabolic rates of cyanide by seedlings were all positively correlated to the concentrations supplied. A negligible difference was observed between the two treatments with nitrate and ammonium (p>0.05). Enzymatic assays showed that cyanide (≥0.97mg CN L(-1)) impaired NR activity significantly in both roots and shoots (p<0.05). The effect of cyanide on GS activity in roots was more evident at 1.93mg CN L(-1), suggesting that NR activity was more susceptible to change from cyanide application than GS activity. The results observed here suggest that the exogenous cyanide, which to a certain level has a beneficial role in plant nutrition. PMID:22633925

  10. Biochemical and Molecular Characterization of Potential Phosphate-Solubilizing Bacteria in Acid Sulfate Soils and Their Beneficial Effects on Rice Growth

    PubMed Central

    Panhwar, Qurban Ali; Naher, Umme Aminun; Jusop, Shamshuddin; Othman, Radziah; Latif, Md Abdul; Ismail, Mohd Razi

    2014-01-01

    A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmolc kg−1, respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils. PMID:25285745

  11. Biochemical and molecular characterization of potential phosphate-solubilizing bacteria in acid sulfate soils and their beneficial effects on rice growth.

    PubMed

    Panhwar, Qurban Ali; Naher, Umme Aminun; Shamshuddin, Jusop; Jusop, Shamshuddin; Othman, Radziah; Latif, Md Abdul; Ismail, Mohd Razi

    2014-01-01

    A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmol(c) kg(-1), respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils. PMID:25285745

  12. Iron biofortification of rice using different transgenic approaches

    PubMed Central

    2013-01-01

    More than 2 billion people suffer from iron (Fe) deficiency, and developing crop cultivars with an increased concentration of micronutrients (biofortification) can address this problem. In this review, we describe seven transgenic approaches, and combinations thereof, that can be used to increase the concentration of Fe in rice seeds. The first approach is to enhance the Fe storage capacity of grains through expression of the Fe storage protein ferritin under the control of endosperm-specific promoters. Using this approach, the concentration of Fe in the seeds of transformants was increased by approximately 2-fold in polished seeds. The second approach is to enhance Fe translocation by overproducing the natural metal chelator nicotianamine; using this approach, the Fe concentration was increased by up to 3-fold in polished seeds. The third approach is to enhance Fe influx to the endosperm by expressing the Fe(II)-nicotianamine transporter gene OsYSL2 under the control of an endosperm-specific promoter and sucrose transporter promoter, which increased the Fe concentration by up to 4-fold in polished seeds. The fourth approach is introduction of the barley mugineic acid synthesis gene IDS3 to enhance Fe uptake and translocation within plants, which resulted in a 1.4-fold increase in the Fe concentration in polished seeds during field cultivation. In addition to the above approaches, Fe-biofortified rice was produced using a combination of the first, second, and third approaches. The Fe concentration in greenhouse-grown T2 polished seeds was 6-fold higher and that in paddy field-grown T3 polished seeds was 4.4-fold higher than in non-transgenic seeds without any reduction in yield. When the first and fourth approaches were combined, the Fe concentration was greater than that achieved by introducing only the ferritin gene, and Fe-deficiency tolerance was observed. With respect to Fe biofortification, the introduction of multiple Fe homeostasis genes is more effective

  13. The impact of volunteer rice infestation on rice yield and grain quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volunteer rice (Oryza sativa L.) is a crop stand which emerges from shattered seeds of the previous crop. When present at sufficiently high levels, it can potentially affect the commercial market value of cultivated rice products, especially if it produces kernels with quality, uniformity, or size ...

  14. Effect of organic materials and rice cultivars on methane emission from rice field.

    PubMed

    Khosa, Maninder Kaur; Sidhu, B S; Benbi, D K

    2010-05-01

    A field experiment was conducted for two years on a sandy loam (Typic Ustochrept) soil of Punjab to study the effect of organic materials and rice cultivars on methane emission from rice fields. The methane flux varied between 0.04 and 0.93 mg m(-2) hr(-1) in bare soil and transplanting of rice crop doubled the methane flux (0.07 to 2.06 mg m(-2) hr(-1)). Among rice cultivars, significantly (p < 0.05) higher amount of methane was emitted from Pusa 44 compared to PR 118 and PR 111. Application of organic materials enhanced methane emission from rice fields and resulted in increased soil organic carbon content. The greatest seasonal methane flux was observed in wheat straw amended plots (229.6 kg ha(-1)) followed by farmyard manure (111.6 kg ha(-1)), green manure (85.4 kg ha(-1)) and the least from rice straw compost amended plots (36.9 kg ha(-1)) as compared to control (21.5 kg ha(-1)). The differential effect of organic materials in enhancing methane flux was related to total carbon or C:N ratio of the material. The results showed that incorporation of humified organic matter such as rice straw compost could minimize methane emission from rice fields with co-benefits of increased soil fertility and crop productivity. PMID:21046997

  15. Feasibility of Simultaneous Rough Rice Drying and Disinfestations by Infrared Radiation Heating and Rice Milling Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to investigate the drying characteristics, milling quality and effectiveness of disinfestation of rough rice under conditions of infrared (IR) radiation heating. Freshly harvested medium grain rice (M202) samples with low (20.6%) and high (25.0%) moisture contents (M...

  16. Characterization of rice blast resistance gene Pi61(t) in rice germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Identification of resistance (R) genes to races of Magnaporthe oryzae in rice germplasm is essential for the development of rice cultivars with long lasting blast resistance. In the present study, one major quantitative trait locus, qPi93-3, was fine mapped using a recombinant inbred line (RIL), F8 ...

  17. Electrophysiological responses of the rice leaffolder, cnaphalocrocis medinalis (lepidoptera: pyralidae), to rice plant volatiles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The electrophysiological activities of 38 synthetic volatiles that were known to be released from the rice plants (Poaceae: Oryza spp.) were studied using electroantennogram (EAG) recording technique on male and female antennae of the rice leaffolder, Cnaphalocrocis medinalis (Guenée) (Lepidoptera: ...

  18. Rice bran stabilization and rice bran oil extraction using ohmic heating.

    PubMed

    Lakkakula, N Rao; Lima, Marybeth; Walker, Terry

    2004-04-01

    Ohmic heating has been shown to increase the extraction yields of sucrose from sugar beets, apple juice from apples, beet dye from beet root, and soymilk from soybeans. Rice bran is a byproduct of the rice milling process that has economic potential by virtue of highly nutritious rice bran oil contained within the bran. In this study, ohmic heating was used to stabilize rice bran and to improve rice bran oil extraction yield as compared to microwave heating and a control (no heating). Results showed that ohmic heating is an effective method for rice bran stabilization with moisture addition. Free fatty acid concentration increased more slowly than the control for raw bran samples subjected to ohmic heating with no corresponding temperature rise, indicating that electricity has a non-thermal effect on lipase activity. Ohmic heating increased the total percent of lipids extracted from rice bran to a maximum of 92%, while 53% of total lipids were extracted from the control samples. Lowering the frequency of alternating current significantly increased the amount of oil extracted, probably due to electroporation. Ohmic heating was successfully applied to rice bran despite its high oil content. This could have important implications for the enhanced extraction of non-polar constituents. PMID:14693448

  19. Functional properties as affected by laboratory-scale parboiling of rough rice and brown rice.

    PubMed

    Patindol, J; Newton, J; Wang, Y-J

    2008-10-01

    Rough rice (RR) is the conventional feedstock for parboiling. The use of brown rice (BR) instead of RR is gaining interest because it results in shorter processing time and lower energy requirement. This study compared the functional properties of milled parboiled rice under different parboiling conditions from RR and BR. Presoaked RR and BR from cultivars Bolivar, Cheniere, Dixiebelle, and Wells were parboiled under mild (20 min, 100 degrees C, 0 kPa) and severe (20 min, 120 degrees C, 98 kPa) laboratory-scale conditions. Head rice yield improved on the RR and BR samples subjected to severe parboiling and was comparable to that of a commercially parboiled sample. Mild parboiling of BR resulted in lower head rice yields. Parboiling generally resulted in decreased head rice whiteness, decreased apparent amylose, increased total lipid, and sparingly changed protein content. Under the same parboiling conditions, the extent of starch gelatinization was higher for BR compared to RR as manifested by some distinct differences in pasting and thermal properties. The cooking characteristics (water uptake ratio, leached materials, and volumetric expansion) and cooked rice texture (hardness and stickiness) of RR and BR subjected to severe parboiling were fairly comparable. Differences in parboiled rice functional properties due to cultivar effect were evident. PMID:19019108

  20. Promising weed suppressive activity in high-yielding indica rice and hybrid rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective weed control in U.S. rice has relied primarily on herbicides since the 1960s. Several indica rice lines tested in the 1980s suppressed aquatic weeds. Since then, they and their crosses with standard U.S. cultivars, and other indica lines were found to suppress barnyardgrass (Echinochloa ...

  1. Gene flow from weedy rice populations to cultivated rice varies by plant type

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gene transfer from crops to its weedy and/or wild relatives has been the research focal point during the last decade. Little is known about the rate and consequences of gene transfer from wild or weedy relatives to the cultivated crops. Red rice, a weed which infests ~ 40% of rice acreage in the sou...

  2. Solvent fractionation of rice bran oil to produce a spreadable rice bran product

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice bran oil is becoming increasingly popular as a functional ingredient, due to its high stability and health benefits. We detail here a new extraction procedure for the production of a spreadable product derived from rice bran oil. Four different experimental conditions for extraction yielded f...

  3. Tier 1 Rice Model for Estimating Pesticide Concentrations in Rice Paddies

    EPA Science Inventory

    The Tier 1 Rice Model estimates screening level aquatic concentrations of pesticides in rice paddies. It is a simple pesticide soil:water partitioning model with default values for water volume, soil mass, and organic carbon. Pesticide degradation is not considered in the mode...

  4. Current progress on genetic interactions of rice with rice blast and sheath blight fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analysis of genetic interactions between rice and its pathogenic fungi Magnaporthe oryzae and Rhizoctonia solani should lead to a better understanding of molecular mechanisms of host resistance, and the improvement of strategies to manage rice blast and sheath blight diseases. Presently dozens of ri...

  5. RiceNet v2: an improved network prioritization server for rice genes

    PubMed Central

    Lee, Tak; Oh, Taeyun; Yang, Sunmo; Shin, Junha; Hwang, Sohyun; Kim, Chan Yeong; Kim, Hyojin; Shim, Hongseok; Shim, Jung Eun; Ronald, Pamela C.; Lee, Insuk

    2015-01-01

    Rice is the most important staple food crop and a model grass for studies of bioenergy crops. We previously published a genome-scale functional network server called RiceNet, constructed by integrating diverse genomics data and demonstrated the use of the network in genetic dissection of rice biotic stress responses and its usefulness for other grass species. Since the initial construction of the network, there has been a significant increase in the amount of publicly available rice genomics data. Here, we present an updated network prioritization server for Oryza sativa ssp. japonica, RiceNet v2 (http://www.inetbio.org/ricenet), which provides a network of 25 765 genes (70.1% of the coding genome) and 1 775 000 co-functional links. Ricenet v2 also provides two complementary methods for network prioritization based on: (i) network direct neighborhood and (ii) context-associated hubs. RiceNet v2 can use genes of the related subspecies O. sativa ssp. indica and the reference plant Arabidopsis for versatility in generating hypotheses. We demonstrate that RiceNet v2 effectively identifies candidate genes involved in rice root/shoot development and defense responses, demonstrating its usefulness for the grass research community. PMID:25813048

  6. RL-SAGE ANALYSIS OF THE RICE DEFENSE TRANSCRIPTOME DURING RICE AND RHIZOCTONIA SOLANI INTERACTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sheath blight caused by the fungal pathogen Rhizoctonia solani is an emerging problem in rice production worldwide. To elucidate the molecular basis of rice defense to the pathogen, two RL-SAGE libraries were made from the R. solani infected and control plants of Jasmine 85, which is moderately resi...

  7. Stimulation by Hyphopichia burtonii and Bacillus amyloliquefaciens of aflatoxin production by Aspergillus flavus in irradiated maize and rice grains

    SciTech Connect

    Cuero, R.G.; Smith, J.E.; Lacey, J.

    1987-05-01

    Aspergillus flavus was grown on maize and rice extract agars and on irradiated viable cracked maize and rice grains, either in pure culture or in dual culture with wild strains of either Hyphopichia burtonii or Bacillus amyloliquefaciens. Aflatoxin production by A. flavus and its growth and interactions with the other microorganisms were studied at three water activities (a/sub w/) (0.98, 0.95, and 0.90) and two temperatures (25 and 16/sup 0/C). Both H. burtonii and B. amyloliquefaciens markedly stimulated growth and aflotoxin production by A. flavus on cracked maize, especially at 25/sup 0/C and 0.95 and 0.98 a/sub w/. No aflatoxin was detected in pure cultures of A. flavus on cracked rice after 12 days of incubation at 25/sup 0/C, but some was produced by mixed cultures at 16/sup 0/C and 0.98 a/sub w/. The morphological interactions among A. flavus, H. burtonii, and B. amyloliquefaciens were also examined on maize and rice extract agars under similar controlled conditions.

  8. Effect of lambda cyhalothrin on Calothrix sp. (GUEco 1001), an autochthonous cyanobacterium of rice fields of Brahmaputra floodplain.

    PubMed

    Gupta, Kiran; Baruah, P P

    2015-12-01

    Pesticide contamination in the rice fields has manifested into a serious global environmental concern. Application of pesticides in the rice fields has deleterious effects on non-target organisms including nitrogen-fixing cyanobacteria which help to maintain the rice field fertility. In the present research endeavor, the effect of lambda cyhalothrin (5% EC), a synthetic pyrethroid insecticide, has been studied on the growth and pigments content of Calothrix sp. (GUEco 1001), an indigenous strain isolated from rice grown areas of Brahmaputra floodplain. To study the toxic effect of lambda cyhalothrin, the test organism was exposed to varying concentrations of the insecticide i.e., 20 ppm, 40 ppm, 80 ppm, and 160 ppm based upon the determination of LC50 for a period of 20 days. The result obtained in the laboratory showed a progressive decrease in the growth and pigments content by the test organism with increasing concentrations of the lambda cyhalothrin against time dose-dependent manner. At high dose (160 ppm), the test organism showed significant decrease in dry weight biomass (54.5%), chlorophyll-a (68%), carotenoids (38%), phycocyanin (80%), and nitrogen contents (55%) over the control. A little but insignificant stimulatory effect on growth and chlorophyll-a contents was recorded in 20 ppm treatment of the insecticide that, however, was reversed in case of carotenoids and phycocyanin contents. PMID:26377968

  9. Odor-active compounds in cooked rice cultivars from Camargue (France) analyzed by GC-O and GC-MS.

    PubMed

    Maraval, Isabelle; Mestres, Christian; Pernin, Karine; Ribeyre, Fabienne; Boulanger, Renaud; Guichard, Elisabeth; Gunata, Ziya

    2008-07-01

    Volatile compounds of cooked rice from scented (Aychade, Fidji) and nonscented (Ruille) cultivars grown in the Camargue area in France were compared to that of a marketed Asian scented one (Thai) by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). GC-O analyses of the organic extracts resulted in the perception of 40 odorous compounds. Only two compounds, oct-1-en-3-one and 2-acetyl-1-pyrroline, were almost always perceived. Hierarchical cluster analysis showed that most of the difference between rice odors was linked to quantitative differences with only 11 compounds being specific to some of the rice. Sixty compounds were identified and quantified by GC-MS, including a few new odor-active components. Principal component analysis enabled us to differentiate scented cultivars from a nonscented one, and scented rice cultivars from Camargue from a Thai sample. Calculated odor-active values evidenced that the Thai sample odor differed from that of scented Camargue cultivars because of the degradation of lipids and of cinnamic acid compounds. PMID:18547050

  10. Molecule diagram from space-grown crystals

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Researchers' at Hauptman-Woodward Medical Research Institute, in Buffalo, N.Y. have analyzed the molecular structures of insulin crystals grown during Space Shuttle experiments and are unlocking the mystery of how insulin works.

  11. [Effect of rice-duck mutualism on nutrition ecology of paddy field and rice quality].

    PubMed

    Wang, Qiangsheng; Huang, Pisheng; Zhen, Ruohong; Jing, Liuming; Tang, Hebao; Zhang, Chunyang

    2004-04-01

    The production of nuisanceless rice was conducted by the technique of rice-duck mutualism without applying any pesticide and chemical fertilizer. The results showed that compared to the control, the effect of eliminating weeds was over 99.4%, and the cardinal numbers of plant diseases and insect pests reduced obviously. Nutrients and dissolved oxygen in paddy water and rapidly available nutrients in soil increased, but after maturing stage, compared to basal fertility, rapidly available P and K decreased. The N, P, and K absorption amounts of rice plant, rice yield, setting panicles rate, filled grains and ripened rate increased. The milling, appearance, nutritional, cooking and eating quality of rice improved, especially in reducing chalkiness. The comprehensive benefits of paddy field enhanced obviously. PMID:15334961

  12. Effect of Temperature on Chinese Rice Wine Brewing with High Concentration Presteamed Whole Sticky Rice

    PubMed Central

    Zhang, Hong-Tao; Xiong, Weili; Hu, Jianhua; Xu, Baoguo; Lin, Chi-Chung; Xu, Ling; Jiang, Lihua

    2014-01-01

    Production of high quality Chinese rice wine largely depends on fermentation temperature. However, there is no report on the ethanol, sugars, and acids kinetics in the fermentation mash of Chinese rice wine treated at various temperatures. The effects of fermentation temperatures on Chinese rice wine quality were investigated. The compositions and concentrations of ethanol, sugars, glycerol, and organic acids in the mash of Chinese rice wine samples were determined by HPLC method. The highest ethanol concentration and the highest glycerol concentration both were attained at the fermentation mash treated at 23°C. The highest peak value of maltose (90 g/L) was obtained at 18°C. Lactic acid and acetic acid both achieved maximum values at 33°C. The experimental results indicated that temperature contributed significantly to the ethanol production, acid flavor contents, and sugar contents in the fermentation broth of the Chinese rice wines. PMID:24672788

  13. Construction of a rice glycosyltransferase phylogenomic database and identification of rice-diverged glycosyltransferases.

    PubMed

    Cao, Pei-Jian; Bartley, Laura E; Jung, Ki-Hong; Ronald, Pamela C

    2008-09-01

    Glycosyltransferases (GTs; EC 2.4.x.y) constitute a large group of enzymes that form glycosidic bonds through transfer of sugars from activated donor molecules to acceptor molecules. GTs are critical to the biosynthesis of plant cell walls, among other diverse functions. Based on the Carbohydrate-Active enZymes (CAZy) database and sequence similarity searches, we have identified 609 potential GT genes (loci) corresponding to 769 transcripts (gene models) in rice (Oryza sativa), the reference monocotyledonous species. Using domain composition and sequence similarity, these rice GTs were classified into 40 CAZy families plus an additional unknown class. We found that two Pfam domains of unknown function, PF04577 and PF04646, are associated with GT families GT61 and GT31, respectively. To facilitate functional analysis of this important and large gene family, we created a phylogenomic Rice GT Database (http://ricephylogenomics.ucdavis.edu/cellwalls/gt/). Through the database, several classes of functional genomic data, including mutant lines and gene expression data, can be displayed for each rice GT in the context of a phylogenetic tree, allowing for comparative analysis both within and between GT families. Comprehensive digital expression analysis of public gene expression data revealed that most ( approximately 80%) rice GTs are expressed. Based on analysis with Inparanoid, we identified 282 'rice-diverged' GTs that lack orthologs in sequenced dicots (Arabidopsis thaliana, Populus tricocarpa, Medicago truncatula, and Ricinus communis). Combining these analyses, we identified 33 rice-diverged GT genes (45 gene models) that are highly expressed in above-ground, vegetative tissues. From the literature and this analysis, 21 of these loci are excellent targets for functional examination toward understanding and manipulating grass cell wall qualities. Study of the remainder may reveal aspects of hormone and protein metabolism that are critical for rice biology. This list

  14. Development of Ozone Technology Rice Storage Systems (OTRISS) for Quality Improvement of Rice Production

    NASA Astrophysics Data System (ADS)

    Nur, M.; Kusdiyantini, E.; Wuryanti, W.; Winarni, T. A.; Widyanto, S. A.; Muharam, H.

    2015-06-01

    This research has been carried out by using ozone to address the rapidly declining quality of rice in storage. In the first year, research has focused on the rice storage with ozone technology for small capacity (e.g., household) and the medium capacity (e.g., dormitories, hospitals). Ozone was produced by an ozone generator with Dielectric Barrier Discharge Plasma (DBDP). Ozone technology rice storage system (OTRISS) is using ozone charateristic which is a strong oxidizer. Ozone have a short endurance of existence and then decompose, as a result produce oxygen and radicals of oxygen. These characteristics could kill microorganisms and pests, reduce air humidity and enrich oxygen. All components used in SPBTO assembled using raw materials available in the big cities in Indonesia. Provider of high voltage (High Voltage Power Supply, 40-70 kV, 23 KH, AC) is one of components that have been assembled and tested. Ozone generator is assembled with 7 reactors of Dielectric Barrier Discharge Plasma (DBDP). Rice container that have been prepared for OTRISS have adjusted so can be integrated with generator, power supply and blower to blow air. OTRISS with a capacity of 75 kg and 100 kg have been made and tested. The ability of ozone to eliminate bacteria and fungi have been tested and resulted in a decrease of microorganisms at 3 log CFU/g. Testing in food chemistry showed that ozone treatment of rice had not changed the chemical content that still meet the standard of chemical content and nutritional applicable to ISO standard milled rice. The results of this study are very likely to be used as an alternative to rice storage systems in warehouse. Test and scale-up is being carried out in a mini warehouse whose condition is mimicked to rice in National Rice Storage of Indonesia (Bulog) to ensure quality. Next adaptations would be installed in the rice storage system in the Bulog.

  15. Microscopic Aspects of Silicon-Mediated Rice Resistance to Leaf Scald.

    PubMed

    Araujo, Leonardo; Paschoalino, Rayane Silva; Rodrigues, Fabrício Ávila

    2016-02-01

    This study investigated the effect of silicon (Si) on the potentiation of rice resistance against leaf scald at the microscopic level. Rice plants ('Primavera') were grown in a nutrient solution containing 0 (-Si) or 2 mM (+Si) Si. The foliar Si concentration of the +Si plants (3.6 dag/kg) increased in comparison with the -Si plants (0.3 dag/kg). An X-ray microanalysis revealed that the leaf tissue of +Si plants infected with Microdochium oryzae had higher peaks and deposition of insoluble Si than that of -Si plants. The high foliar Si concentration for the +Si plants reduced the expansion of leaf scald lesions. Scanning electron microscopy revealed that fungal hyphae and appressorium-like structures of M. oryzae were more abundant in the leaf surface of -Si plants relative to +Si plants. At both histopathological and ultrastructural levels, fungal hyphae grew abundantly into the leaf tissue of -Si plants. By contrast, rice cell walls were rarely degraded and fungal hyphae were often surrounded by amorphous granular material in the leaf tissue of +Si plants. Conidiophores emerged from stomata 36 h after fungal penetration, and conidia were noticed inside the leaf tissue of the -Si plants in great abundance. The collective results of the present study showed a high concentration and deposition of Si and a considerable deposition of phenolic-like compounds in the leaf tissue of +Si plants. These results indicate that the potentiation of the phenylpropanoid pathway in these plants supplied with Si was favorable for the increase in rice resistance to leaf scald. PMID:26237696

  16. Do arbuscular mycorrhizal fungi affect cadmium uptake kinetics, subcellular distribution and chemical forms in rice?

    PubMed

    Li, Hui; Luo, Na; Zhang, Li Jun; Zhao, Hai Ming; Li, Yan Wen; Cai, Quan Ying; Wong, Ming Hung; Mo, Ce Hui

    2016-11-15

    Rice (Oryza sativa L.) plants were inoculated with two species of arbuscular mycorrhizal fungi (AMF) - Rhizophagus intraradices (RI) and Funneliformis mosseae (FM) and grown for 60days to ensure strong colonization. Subsequently, a short-term hydroponic experiment was carried out to investigate the effects of AMF on cadmium (Cd) uptake kinetics, subcellular distribution and chemical forms in rice exposed to six Cd levels (0, 0.005, 0.01, 0.025, 0.05, 0.1mM) for three days. The results showed that the uptake kinetics of Cd fitted the Michaelis-Menten model well (R(2)>0.89). AMF significantly decreased the Cd concentrations both in shoots and roots in Cd solutions. Furthermore, the decrement of Cd concentrations by FM was significantly higher than RI treatment in roots. AMF reduced the Cd concentrations markedly in the cell wall fractions at high Cd substrate (≥0.025mM). The main subcellular fraction contributed to Cd detoxification was cell wall at low Cd substrate (<0.05mM), while vacuoles at high Cd substrate (≥0.05mM). Moreover, the concentrations and proportions of Cd in inorganic and water-soluble form also reduced by AMF colonization at high Cd substrate (≥0.05mM), both in shoots and roots. This suggested that AMF could convert Cd into inactive forms which were less toxic. Therefore, AMF could enhance rice resistance to Cd through altering subcellular distribution and chemical forms of Cd in rice. PMID:27450963

  17. Rice ORMDL controls sphingolipid homeostasis affecting fertility resulting from abnormal pollen development.

    PubMed

    Chueasiri, Chutharat; Chunthong, Ketsuwan; Pitnjam, Keasinee; Chakhonkaen, Sriprapai; Sangarwut, Numphet; Sangsawang, Kanidta; Suksangpanomrung, Malinee; Michaelson, Louise V; Napier, Johnathan A; Muangprom, Amorntip

    2014-01-01

    The orosomucoids (ORM) are ER-resisdent polypeptides encoded by ORM and ORMDL (ORM-like) genes. In humans, ORMDL3 was reported as genetic risk factor associated to asthma. In yeast, ORM proteins act as negative regulators of sphingolipid synthesis. Sphingolipids are important molecules regulating several processes including stress responses and apoptosis. However, the function of ORM/ORMDL genes in plants has not yet been reported. Previously, we found that temperature sensitive genetic male sterility (TGMS) rice lines controlled by tms2 contain a deletion of about 70 kb in chromosome 7. We identified four genes expressed in panicles, including an ORMDL ortholog, as candidates for tms2. In this report, we quantified expression of the only two candidate genes normally expressed in anthers of wild type plants grown in controlled growth rooms for fertile and sterile conditions. We found that only the ORMDL gene (LOC_Os07g26940) showed differential expression under these conditions. To better understand the function of rice ORMDL genes, we generated RNAi transgenic rice plants suppressing either LOC_Os07g26940, or all three ORMDL genes present in rice. We found that the RNAi transgenic plants with low expression of either LOC_Os07g26940 alone or all three ORMDL genes were sterile, having abnormal pollen morphology and staining. In addition, we found that both sphingolipid metabolism and expression of genes involved in sphingolipid synthesis were perturbed in the tms2 mutant, analogous to the role of ORMs in yeast. Our results indicated that plant ORMDL proteins influence sphingolipid homeostasis, and deletion of this gene affected fertility resulting from abnormal pollen development. PMID:25192280

  18. Internal Zn allocation influences Zn deficiency tolerance and grain Zn loading in rice (Oryza sativa L.)

    PubMed Central

    Impa, Somayanda M.; Gramlich, Anja; Tandy, Susan; Schulin, Rainer; Frossard, Emmanuel; Johnson-Beebout, Sarah E.

    2013-01-01

    One of the important factors that influences Zn deficiency tolerance and grain Zn loading in crops is the within-plant allocation of Zn. Three independent experiments were carried out to understand the internal Zn distribution patterns in rice genotypes grown in Zn-sufficient and Zn-deficient agar nutrient solution (ANS). In one of the experiments, two rice genotypes (IR55179 and KP) contrasting in Zn deficiency tolerance were leaf-labeled with 65Zn. In the other two experiments, two Zn biofortification breeding lines (IR69428 and SWHOO) were either root- or leaf-labeled with 65Zn. Rice genotype IR55179 showed significantly higher Zn deficiency tolerance than KP at 21 and 42 days after planting. When KP was Zn-deficient, it failed to translocate 65Zn from the labeled leaf to newly emerging leaves. Similarly, the root-to-shoot translocation of unlabeled Zn was lower in KP than in IR55179. These results suggest that some Zn-efficient rice genotypes have greater ability to translocate Zn from older to actively growing tissues than genotypes sensitive to Zn deficiency. Among the two Zn biofortication breeding lines that were leaf-labeled with 65Zn at 10 days before panicle initiation stage, 65Zn distribution in the grains at maturity was similar between both genotypes in Zn-sufficient conditions. However, under Zn-deficient conditions, SWHOO accumulated significantly higher 65Zn in grains than IR69428, indicating that SWHOO is a better remobilizer than IR69428. When the roots of these two Zn biofortication breeding lines were exposed to 65Zn solution at 10 days after flowering, IR69428 showed higher root uptake of 65Zn than SWHOO in Zn-sufficient conditions, but 65Zn allocation in the aerial parts of the plant was similar between both genotypes. PMID:24400015

  19. Fingerprint of Seasonal Relative humidity in Rice (Oryza sativa L.): Potential for Paleoclimate Archive

    NASA Astrophysics Data System (ADS)

    Kaushal, R.; Ghosh, P.

    2015-12-01

    Seasonal variability of relative humidity (RH) condition during southwest monsoon (SWM) is strongly related with availability of moisture for rainfall over the continental region. There are ongoing efforts to reconstruct the past monsoonal condition based on geochemical and isotopic records as proxies [1]. However, limited archives have been successfully retrieved for reconstructing moisture condition during SWM [2]. Potential of plants as climate archives and the mechanism involved in transfer of climate signature to the stable isotope composition of oxygen (δ18O) has been demonstarted successfully [3]. Here we are introducing δ18O of rice grain bulk organic matter (δ18OOM) as a new proxy for precise determination of RH during SWM. Rice is a seasonal crop and widely cultivated over the Indian subcontinent during SWM. Here we present δ18OOM of rice grains collected from 15 locations from different climatic zones over the Indian subcontinent, ranging from semi-arid to humid-perhumid. These samples were collected from the harvest of the crop grown at the time of SWM for the period 2012-2014. Each of these climatic zones are characterized by unique range of RH values, which is expected to leave distinct oxygen isotopic signature in the rice grain OM. We compared the δ18OOM values with δ18O of precipitation water, RH and temperature during the period of cultivation. Precipitation δ18O values were obtained from were obtained from OPIC [4]. Our observations document a significant relationship between δ18OOM and RH (R2 =0.62, p<0.001). When the RH level fluctuated from 65% to 88%, δ18OOM tended to vary between 31.5 ‰ to 15.4‰. However, the humid regions with rainfed crop showed significant relationship between δ18OOM and precipitation δ18O. Remaining stations being fed by the both rain and irrigation from river/ groundwater, dampen the rainfall isotope signature in δ18OOM. This approach can be extended in deriving RH of regions of rice cultivation by

  20. THE BENTHIC COMMUNITIES COMPARISON BETWEEN ORGANIC AND CONVENTIONAL RICE FIELDS.

    PubMed

    Kasamesiri, P; Thaimuangphol, W

    2015-01-01

    Rice fields are temporary wetlands prone to contamination from agricultural chemicals which affect their ecotoxicology and benthic community composition. The diversity of benthic fauna in both organic and conventional rice fields in Kalasin Province, Thailand was investigated. Benthos samples were collected by grab sampling from 20 stations in organic and conventional rice fields during one successive crop in August 2014. The number of benthic organisms found at each sampling station ranged from 16-518 and 24-137 individuals for organic and conventional rice fields, respectively. The benthic fauna in organic rice fields were dominated by crustaceans 41%, insects 31%, annelids 26%, and gastropods 2%. The conventional rice fields benthic fauna was composed of insects 51%, annelids 41%, and gastropods 8%. The abundance and composition of the benthic fauna demonstrated that organic rice farming practices are beneficial to sustaining the biodiversity in rice field ecosystems. PMID:27141733

  1. Developing and delivering biofortified Rice to the consumer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofortified rice varieties include those that have been enhanced for protein, vitamins, minerals, or other nutritional compounds. Delivering biofortified rice varieties carries with it extra challenges as compared to conventional varieties. Nutritional compounds must be present at significantly hig...

  2. Production of Beauveria bassiana Fungal Spores on Rice to Control the Coffee Berry Borer, Hypothenemus hampei, in Colombia

    PubMed Central

    Posada-Flórez, Francisco J

    2008-01-01

    Two isolates of fungal entomopathogen Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) were grown on cooked rice using diphasic liquid-solid fermentation in plastic bags to produce and harvest spore powder. The cultures were dried and significant differences were found for isolates and time of harvest. The spores were harvested manually and mechanically and after the cultures were dried for nine days, when moisture content was near 10%. After harvesting, spores were submitted to quality control to assess concentration, germination, purity, moisture content, particle size and pathogenicity to the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae). Spore productivity on cooked rice was less than 1×1010 spores/g using both manually and mechanically harvesting methodologies. Germination at 24 hours was over 75% and pathogenicity against H. hampei was over 92.5%. This methodology is suitable for laboratory and field studies, but not for industrial production when a high concentration of spores are required for formulation and field applications.

  3. Cadmium accumulation retard activity of functional components of photo assimilation and growth of rice cultivars amended with vermicompost.

    PubMed

    Sebastian, Abin; Prasad, M N V

    2013-01-01

    Cadmium (Cd) uptake mediated alterations in functional components of photo assimilation during conversion of cow dung and poultry cast to vermicompost were studied in two Indian rice cultivars; MO 16 and MTU 7029. It was found that higher amount of Cd accumulate in plants grown in soil amended with vermicompost which in turn damaged functional components in photo assimilation. Enhancement of root growth was recognized as reason for Cd accumulation. Metabolic alterations noticed among plants were not taken place during application of raw materials used for vermicomposting such as cow dung and poultry cast amendment. Rice varieties accumulated Cd differentially where MTU 7029 accumulated more Cd compare to MO 16. It was also noticed that existence of negative correlation between zinc status of the plant and Cd accumulation. PMID:23819289

  4. Sensitivity of light-grown and dark-grown Euglena cells to gamma-irradiation.

    PubMed

    Nair, K A; Netrawali, M S

    1979-09-01

    Light-grown cells which contain fully developed chloroplasts were found to be more resistant to gamma-irradiation than dark-grown cells which are devoid of chloroplasts. The radio-resistance of dark-grown cells progressively increased during light-induced development of chloroplasts and, conversely, radio-resistance of light-grown cells decreased progressively with chloroplast de-development during growth in the dark. The presence of chloroplasts seemed to play a major role in the capacity of cells to recover from radiation damage, the efficiency of cellular recovery being correlatable with the degree of chloroplast development. PMID:315395

  5. Effects of silicon (Si) on arsenic (As) accumulation and speciation in rice (Oryza sativa L.) genotypes with different radial oxygen loss (ROL).

    PubMed

    Wu, Chuan; Zou, Qi; Xue, Shengguo; Mo, Jingyu; Pan, Weisong; Lou, Laiqing; Wong, Ming Hung

    2015-11-01

    Arsenic (As) contamination of paddy soils has adversely affected the health of millions of people those consuming rice for staple food. The present study was aimed at investigating the effects of silicon (Si) fertilization on As uptake, speciation in rice plants with different radial oxygen loss (ROL). Six genotypes were planted in pot soils under greenhouse conditions until late tillering state. The results showed that the rates of ROL were higher in hybrid rice genotypes varying from 19.76 to 27 μmol O2 g(-1) root dry weight h(-1) than that in conventional indica rice genotypes varying from 9.55 to 15.41 μmol O2 g(-1) root dry weight h(-1). Si addition significantly increased straw biomass (p<0.005), but with no significant effects on root biomass. Si fertilization significantly reduced shoot and root total As concentrations (p<0.001) in six genotypes grown in 40 mg As/kg soil. Si addition decreased the inorganic As in shoots of 'Xiangfengyou-9' with lower ROL and 'Xiangwanxian-12' with higher ROL by 31% and 25% respectively and had the tendency to increase DMA concentrations. It is potential to reduce As contamination of rice efficiently by combining Si fertilization and selecting genotypes with high radial oxygen loss. PMID:26171731

  6. Calcium Mitigates Arsenic Toxicity in Rice Seedlings by Reducing Arsenic Uptake and Modulating the Antioxidant Defense and Glyoxalase Systems and Stress Markers

    PubMed Central

    Rahman, Anisur; Mostofa, Mohammad Golam; Alam, Md. Mahabub; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2015-01-01

    The effect of exogenous calcium (Ca) on hydroponically grown rice seedlings was studied under arsenic (As) stress by investigating the antioxidant and glyoxalase systems. Fourteen-day-old rice (Oryza sativa L. cv. BRRI dhan29) seedlings were exposed to 0.5 and 1 mM Na2HAsO4 alone and in combination with 10 mM CaCl2 (Ca) for 5 days. Both levels of As caused growth inhibition, chlorosis, reduced leaf RWC, and increased As accumulation in the rice seedlings. Both doses of As in growth medium induced oxidative stress through overproduction of reactive oxygen species (ROS) by disrupting the antioxidant defense and glyoxalase systems. Exogenous application of Ca along with both levels of As significantly decreased As accumulation and restored plant growth and water loss. Calcium supplementation in the As-exposed rice seedlings reduced ROS production, increased ascorbate (AsA) content, and increased the activities of monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT), glutathione peroxidase (GPX), superoxide dismutase (SOD), and the glyoxalase I (Gly I) and glyoxalase II (Gly II) enzymes compared with seedlings exposed to As only. These results suggest that Ca supplementation improves rice seedlings tolerance to As-induced oxidative stress by reducing As uptake, enhancing their antioxidant defense and glyoxalase systems, and also improving growth and physiological condition. PMID:26798635

  7. Effect of germination on the physicochemical and antioxidant characteristics of rice flour from three rice varieties from Nigeria.

    PubMed

    Chinma, Chiemela Enyinnaya; Anuonye, Julian Chukwuemeka; Simon, Omotade Comfort; Ohiare, Raliat Ozavize; Danbaba, Nahemiah

    2015-10-15

    This study determined the effect of germination (48 h) on the physicochemical and antioxidant characteristics of rice flour from three rice varieties from Nigeria. Local rice varieties (Jamila, Jeep and Kwandala) were evaluated and compared to an improved variety (MR 219). Physicochemical and antioxidant properties of flours were determined using standard methods. Protein, magnesium, phosphorus, potassium and antioxidant properties of rice flours increased after germination while phytic acid and total starch contents decreased. Foaming capacity and stability of rice flours increased after germination. Germination resulted to changes in pasting and thermal characteristics of rice flours. Germinated rice flours had better physicochemical and antioxidant properties with reduced phytic acid and starch contents compared to MR 219, which can be utilized as functional ingredients in the preparation of rice-based products. PMID:25952893

  8. 21 CFR 172.890 - Rice bran wax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Rice bran wax. 172.890 Section 172.890 Food and... PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.890 Rice bran wax. Rice bran wax may be safely used in food in accordance with the following conditions: (a) It is...

  9. Developing sustainable management practices for organic rice production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Demand for organically produced rice has been increasing with up to 50,000 acres now produced in the USA. Although acreage of conventional rice production has decreased in Texas by 36% during the last 15 years, it is now home to some 15,000 acres of organic rice, which has brought new vitality to ot...

  10. Rice Methylmercury Exposure and Mitigation: A Comprehensive Review

    PubMed Central

    Rothenberg, Sarah E.; Windham-Myers, Lisamarie; Creswell, Joel E.

    2014-01-01

    Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice cultivated or purchased in 15 countries. Not surprisingly, both rice total mercury and methylmercury levels were significantly higher in polluted sites compared to non-polluted sites (Wilcoxon rank sum, p<0.001). However, rice percent methylmercury (of total mercury) did not differ statistically between polluted and non-polluted sites (Wilcoxon rank sum, p=0.35), suggesting comparable mercury methylation rates in paddy soil across these sites and/or similar accumulation of mercury species for these rice cultivars. Studies characterizing the effect of rice cultivation under more aerobic conditions were reviewed to determine the mitigation potential of this practice. Rice management practices utilizing alternating wetting and drying (instead of continuous flooding) caused soil methylmercury levels to spike, resulting in a strong methylmercury pulse after fields were dried and reflooded; however, it is uncertain whether this led to increased translocation of methylmercury from paddy soil to rice grain. Due to the potential health risks, it is advisable to investigate this issue further, and to develop separate water management strategies for mercury polluted and non-polluted sites, which minimize methylmercury exposure through rice ingestion. PMID:24972509

  11. Origins and evolution of weedy rice in the US

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red rice is a weedy form of cultivated rice (Oryza sativa) that infests crop fields and reduces US rice harvests by up to 80%. This agricultural weed has been proposed to arise either through de-domestication of feral US crop germplasm and/or introduction of foreign germplasm (potentially including ...

  12. Rice methylmercury exposure and mitigation: a comprehensive review

    USGS Publications Warehouse

    Rothenberg, Sarah E.; Windham-Myers, Lisamarie; Creswell, Joel E.

    2014-01-01

    Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice (Orzya sativa) cultivated or purchased in 15 countries. Not surprisingly, both rice total mercury and methylmercury levels were significantly higher in polluted sites compared to non-polluted sites (Wilcoxon rank sum, p<0.001). However, rice percent methylmercury (of total mercury) did not differ statistically between polluted and non-polluted sites (Wilcoxon rank sum, p=0.35), suggesting comparable mercury methylation rates in paddy soil across these sites and/or similar accumulation of mercury species for these rice cultivars. Studies characterizing the effects of rice cultivation under more aerobic conditions were reviewed to determine the mitigation potential of this practice. Rice management practices utilizing alternating wetting and drying (instead of continuous flooding) caused soil methylmercury levels to spike, resulting in a strong methylmercury pulse after fields were dried and reflooded; however, it is uncertain whether this led to increased translocation of methylmercury from paddy soil to rice grain. Due to the potential health risks, it is advisable to investigate this issue further, and to develop separate water management strategies for mercury polluted and non-polluted sites, in order to minimize methylmercury exposure through rice ingestion.

  13. Antioxidants and antioxidant activity of several pigmented rice brans.

    PubMed

    Laokuldilok, Thunnop; Shoemaker, Charles F; Jongkaewwattana, Sakda; Tulyathan, Vanna

    2011-01-12

    This study investigated the antioxidant content and activity of phenolic acids, anthocyanins, α-tocopherol and γ-oryzanol in pigmented rice (black and red rice) brans. After methanolic extraction, the DPPH free radical scavenging activity and antioxidant activity were measured. The pigmented rice bran extract had a greater reducing power than a normal rice bran extract from a long grain white rice. All bran extracts were highly effective in inhibiting linoleic acid peroxidation (60-85%). High-performance liquid chromatography (HPLC) analysis of antioxidants in rice bran found that γ-oryzanol (39-63%) and phenolic acids (33-43%) were the major antioxidants in all bran samples, and black rice bran also contained anthocyanins 18-26%. HPLC analysis of anthocyanins showed that pigmented bran was rich in cyanidin-3-glucoside (58-95%). Ferulic acid was the dominant phenolic acid in the rice bran samples. Black rice bran contained gallic, hydroxybenzoic, and protocatechuic acids in higher contents than red rice bran and normal rice bran. Furthermore, the addition of 5% black rice bran to wheat flour used for making bread produced a marked increase in the free radical scavenging and antioxidant activity compared to a control bread. PMID:21141962

  14. Test of Some Hybrid Combinations to Rice Blast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by Magnaporthe oryzae is one of the most devastating rice diseases worldwide. Blast resistant cultivars are recognized as the most efficacious and economical way to control this disease. Genetic resistance to rice blast is generally governed by a few major genes, often in c...

  15. Moisture diffusivity of rough rice under infrared radiation drying

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To design efficient infrared (IR) dryers for rough rice, it is important to understand the drying behavior of rough rice under IR heating. The objective of this study was to determine the moisture diffusivity of rough rice under IR heating followed by cooling. The effects of initial moisture content...

  16. Effective disinfection of rough rice using infrared radiation heating

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to investigate the effect of infrared (IR) heating and tempering treatments on disinfection of Aspergillus flavus in freshly harvested rough rice and storage rice. Rice samples with initial moisture contents (IMCs) of 14.1 to 27.0% (wet basis) were infected with A. fl...

  17. Rice growth monitoring using simulated compact polarimetric C band SAR

    NASA Astrophysics Data System (ADS)

    Yang, Zhi; Li, Kun; Liu, Long; Shao, Yun; Brisco, Brian; Li, Weiguo

    2014-12-01

    In this study, a set of nine compact polarimetric (CP) images were simulated from polarimetric RADARSAT-2 data acquired over a test site containing two types of rice field in Jiangsu province, China. The types of rice field in the test site were (1) transplanted hybrid rice fields, and (2) direct-sown japonica rice fields. Both types have different yields and phenological stages. As a first step, the two types of rice field were distinguished with 94% and 86% accuracy respectively through analyzing CP synthetic aperture radar (SAR) observations and their behavior in terms of scattering mechanisms during the rice growth season. The focus was then on phenology retrieval for each type of rice field. A decision tree (DT) algorithm was built to fulfill the precise retrieval of rice phenological stages, in which seven phenological stages were discriminated. The key criterion for each phenological stage was composed of 1-4 CP parameters, some of which were first used for rice phenology retrieval and found to be very sensitive to rice phenological changes. The retrieval results were verified at parcel level for a set of 12 stands of rice and up to nine observation dates per stand. This gave an accuracy of 88-95%. Throughout the phenology retrieval process, only simulated CP data were used, without any auxiliary data. These results demonstrate the potential of CP SAR for rice growth monitoring applications.

  18. Processing and functionality of rice bran protein and peptides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice bran comprises approximately 10% of the rough rice kernel. Its germ is a rich source of oil; while defatted bran consists of proteins, minerals, vitamins and fibers, or the indigestible carbohydrates. About 61% of the minerals are located in the bran. The rice bran proteins have shown great pot...

  19. Investigating irrigation scheduling for rice using variable rate irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because almost all US rice is produced with continuous flood irrigation, little information addresses irrigation scheduling for rice; however, successful production of rice without a continuous flood will require scheduling, or timely irrigation. A field study conducted at the University of Missouri...

  20. Water absorption properties of ultrasonic treated brown rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To understand the effect of ultrasonic treated on brown rice, it is important to research the water absorption processing of brown rice before and after ultrasonic treatment. The objective of this study was investigate and modeling water absorption characteristics of brown rice using Peleg’s equatio...