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Sample records for susceptible rice varieties

  1. Silicon-mediated resistance in a susceptible rice variety to the rice leaf folder, Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae).

    Science.gov (United States)

    Han, Yongqiang; Lei, Wenbin; Wen, Lizhang; Hou, Maolin

    2015-01-01

    The rice leaf folder, Cnaphalocrocis medinalis (Guenée), is one of the most destructive rice pests in Asian countries. Rice varieties resistant to the rice leaf folder are generally characterized by high silicon content. In this study, silicon amendment, at 0.16 and 0.32 g Si/kg soil, enhanced resistance of a susceptible rice variety to the rice leaf folder. Silicon addition to rice plants at both the low and high rates significantly extended larval development and reduced larval survival rate and pupation rate in the rice leaf folder. When applied at the high rate, silicon amendment reduced third-instars' weight gain and pupal weight. Altogether, intrinsic rate of increase, finite rate of increase and net reproduction rate of the rice leaf folder population were all reduced at both the low and high silicon addition rates. Although the third instars consumed more in silicon-amended treatments, C:N ratio in rice leaves was significantly increased and food conversion efficiencies were reduced due to increased silicon concentration in rice leaves. Our results indicate that reduced food quality and food conversion efficiencies resulted from silicon addition account for the enhanced resistance in the susceptible rice variety to the rice leaf folder.

  2. Silicon-mediated resistance in a susceptible rice variety to the rice leaf folder, Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae.

    Directory of Open Access Journals (Sweden)

    Yongqiang Han

    Full Text Available The rice leaf folder, Cnaphalocrocis medinalis (Guenée, is one of the most destructive rice pests in Asian countries. Rice varieties resistant to the rice leaf folder are generally characterized by high silicon content. In this study, silicon amendment, at 0.16 and 0.32 g Si/kg soil, enhanced resistance of a susceptible rice variety to the rice leaf folder. Silicon addition to rice plants at both the low and high rates significantly extended larval development and reduced larval survival rate and pupation rate in the rice leaf folder. When applied at the high rate, silicon amendment reduced third-instars' weight gain and pupal weight. Altogether, intrinsic rate of increase, finite rate of increase and net reproduction rate of the rice leaf folder population were all reduced at both the low and high silicon addition rates. Although the third instars consumed more in silicon-amended treatments, C:N ratio in rice leaves was significantly increased and food conversion efficiencies were reduced due to increased silicon concentration in rice leaves. Our results indicate that reduced food quality and food conversion efficiencies resulted from silicon addition account for the enhanced resistance in the susceptible rice variety to the rice leaf folder.

  3. Drought susceptibility of modern rice varieties: an effect of linkage of drought tolerance with undesirable traits

    Science.gov (United States)

    Vikram, Prashant; Swamy, B. P. Mallikarjuna; Dixit, Shalabh; Singh, Renu; Singh, Bikram P.; Miro, Berta; Kohli, Ajay; Henry, Amelia; Singh, N. K.; Kumar, Arvind

    2015-01-01

    Green Revolution (GR) rice varieties are high yielding but typically drought sensitive. This is partly due to the tight linkage between the loci governing plant height and drought tolerance. This linkage is illustrated here through characterization of qDTY1.1, a QTL for grain yield under drought that co-segregates with the GR gene sd1 for semi-dwarf plant height. We report that the loss of the qDTY1.1 allele during the GR was due to its tight linkage in repulsion with the sd1 allele. Other drought-yield QTLs (qDTY) also showed tight linkage with traits rejected in GR varieties. Genetic diversity analysis for 11 different qDTY regions grouped GR varieties separately from traditional drought-tolerant varieties, and showed lower frequency of drought tolerance alleles. The increased understanding and breaking of the linkage between drought tolerance and undesirable traits has led to the development of high-yielding drought-tolerant dwarf lines with positive qDTY alleles and provides new hope for extending the benefits of the GR to drought-prone rice-growing regions. PMID:26458744

  4. Drought susceptibility of modern rice varieties: an effect of linkage of drought tolerance with undesirable traits.

    Science.gov (United States)

    Vikram, Prashant; Swamy, B P Mallikarjuna; Dixit, Shalabh; Singh, Renu; Singh, Bikram P; Miro, Berta; Kohli, Ajay; Henry, Amelia; Singh, N K; Kumar, Arvind

    2015-10-13

    Green Revolution (GR) rice varieties are high yielding but typically drought sensitive. This is partly due to the tight linkage between the loci governing plant height and drought tolerance. This linkage is illustrated here through characterization of qDTY1.1, a QTL for grain yield under drought that co-segregates with the GR gene sd1 for semi-dwarf plant height. We report that the loss of the qDTY1.1 allele during the GR was due to its tight linkage in repulsion with the sd1 allele. Other drought-yield QTLs (qDTY) also showed tight linkage with traits rejected in GR varieties. Genetic diversity analysis for 11 different qDTY regions grouped GR varieties separately from traditional drought-tolerant varieties, and showed lower frequency of drought tolerance alleles. The increased understanding and breaking of the linkage between drought tolerance and undesirable traits has led to the development of high-yielding drought-tolerant dwarf lines with positive qDTY alleles and provides new hope for extending the benefits of the GR to drought-prone rice-growing regions.

  5. Environmental and physiological effects on grouping of drought-tolerant and susceptible rice varieties related to rice (Oryza sativa) root hydraulics under drought.

    Science.gov (United States)

    Henry, Amelia; Wehler, Regina; Grondin, Alexandre; Franke, Rochus; Quintana, Marinell

    2016-05-02

    Root hydraulic limitations (i.e. intra-plant restrictions to water movement) may be related to crop performance under drought, and groupings in the hydraulic function of drought-tolerant and drought-susceptible rice (Oryza sativa) varieties have been previously reported. This study aimed to better understand the environmental and physiological relationships with rice root hydraulics under drought. Xylem sap bleeding rates in the field (gsap g(-1)shoot) were measured on seasonal and diurnal time frames, during which time environmental conditions were monitored and physiological measurements were conducted. Complementary experiments on the effects of vapour pressure deficit (VPD) on root hydraulic conductivity and on transpiration rates of de-rooted tillers were conducted in growth chambers. The diurnal effects on bleeding rate were more closely related to irradiance than VPD, and VPD effects on root hydraulic conductivity measured on 21-day-old plants were due to effects on plant growth including root surface area, maximum root depth and root:shoot ratio. Leaf osmotic potential was related to the grouping of drought-tolerant and drought-susceptible varieties in rice root hydraulics, and these groupings were independent of differences in phenology. Low single-tiller bleeding rates were observed under high evapo-transpirational demand, higher bleeding rates were observed at more negative leaf osmotic potentials in drought-susceptible varieties, and drought-tolerant and susceptible varieties differed in the VPD-induced increase in transpiration rates of de-rooted tillers. Low root suberin amounts in some of the drought-susceptible varieties may have resulted in higher ion transport, as evidenced by higher sap K(+) concentration and higher bleeding rates in those varieties. These results provide evidence of the environmental effects on shoots that can influence root hydraulics. The consistent groupings of drought-tolerant and susceptible varieties suggest that traits

  6. Allelopathic potential of selected rice varieties

    African Journals Online (AJOL)

    ajl10

    2012-11-01

    Nov 1, 2012 ... Azania AAPM, Azania CAMP, Alives LCA, Palaniraj R, Kadian HS, Sati. SC, Rawat LS, Dahiya DS, Narwal SS (2003). Allelopathic plants. 7. Barley (Hordeum vulgare L.). Allelopathy J. 11:1–20. Azmi M, Abdullah MZ, Fuji Y (2000). Exploratory study on allelopathic effect of selected Malaysian rice varieties ...

  7. Determinants of adoption and productivity of improved rice varieties ...

    African Journals Online (AJOL)

    The study examines the status of adoption of improved rice varieties and its impact on rice production among smallholder farmers in southwestern Nigeria. Data for this study were generated from a farm survey of rice farmers selected by multi-stage sampling technique in two of the rice producing states of the region.

  8. Preferences of Ugandan consumers for rice varieties and brands on ...

    African Journals Online (AJOL)

    The demand for rice Oryza sativa in Uganda has exceeded local supply resulting into importation of several other rice varieties and brands to meet the deficit. Lack of information on consumer preferences hinders decision-making to invest in the rice sub sector. This study seeks to provide information on consumer ...

  9. Genetic diversity studies on selected rice varieties grown in Africa ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    three improved Sahel aromatic varieties, group 4 was the most diversified group with three sub-clusters and group 5 corresponded ... cooking and eating quality traits and aroma in rice breeding program. Key words: Grain quality, .... created by AfricaRice Sahel station, 15 improved Sahel varieties of different origins mostly ...

  10. Screening lowland rice varieties for resistance to brown spot ...

    African Journals Online (AJOL)

    Twelve lowland rice varieties (BG 90-2, Cisadane, FARO 12, FARO 15 (early maturing), FARO 15 (late maturing), IR 5, ITA 123, ITA 306, MAS 2401, Suakoko 8 and TOS 2578) were planted in 2008 and 2009 growing seasons in Enyong creek rice field in Akwa Ibom State. The varieties were screened for resistance to brown ...

  11. Microstructure and tensile properties of various varieties of rice husk.

    Science.gov (United States)

    Chen, Ziyong; Xu, Yangzi; Shivkumar, Satya

    2017-07-19

    Rice husk is a complex hierarchical assembly of hollow fibers consisting of cellulose, hemicellulose and lignin. In addition, it can also contain pectin and significant amounts of silica. Rice husk can be used in diverse applications and generally in the form of rice husk powder. This study aimed to investigate the structural features and mechanical properties of various varieties of whole rice husks. Rice husk consists of three sections: epidermis, sub-hypodermis and hypodermis. The thickness of these layers, the diameters of the hollow fibers and the wall thickness vary with the variety of rice husk. The elastic modulus is typically between 0.3 and 2.6 GPa, and the ultimate tensile strength varies from 19 to 135 MPa depending on the variety of rice husk. Rice husk has a unique hierarchical structure in which the fibers exhibit a staggered perpendicular arrangement and the entire fiber sections are covered by an external shell. The tensile properties vary with the variety of rice husk. The wide range in these tensile properties may be attributed to the size and orientation of the fibers. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. Comparative transcriptome analysis of two rice varieties in response to rice stripe virus and small brown planthoppers during early interaction.

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    Wenjing Zheng

    Full Text Available Rice stripe, a virus disease, transmitted by a small brown planthopper (SBPH, has greatly reduced production of japonica rice in East Asia, especially in China. Although we have made great progress in mapping resistance genes, little is known about the mechanism of resistance. By de novo transcriptome assembling, we gained sufficient transcript data to analyze changes in gene expression of early interaction in response to SBPH and RSV infection in rice. Respectively 648 and 937 DEGs were detected from the disease-resistant (Liaonong 979 and the susceptible (Fengjin varieties, most of which were up-regulated. We found 37 genes related to insect resistance, which mainly included genes for jasmonate-induced protein, TIFY protein, lipoxygenase, as well as trypsin inhibitor genes and transcription factor genes. In the interaction process between RSV and rice, 87 genes were thought to be related to RSV resistance; these primarily included 12 peroxidase biosynthesis genes, 12 LRR receptor-like protein kinase genes, 6 genes coding pathogenesis-related proteins, 4 glycine-rich cell wall structural protein genes, 2 xyloglucan hydrolase genes and a cellulose synthase. The results indicate that the rice-pathogen interaction happened both in disease-resistant and susceptible varieties, and some genes related to JA biosynthesis played key roles in the interaction between SBPHs and rice. When rice was infected by RSV a hypersensitive reaction (HR in the disease-resistant variety was suppressed, which resulted from an increase in peroxidase expression and down-regulation of LRR receptor-like protein kinase and pathogenesis-related proteins, while, the changes of peroxidase biosynthesis, glycine-rich cell wall structural protein, cellulose synthase and xyloglucan endotransglucosylase/hydrolase could lead to the strengthening of physical barriers of rice, which may be an important resistance mechanism to RSV in rice.

  13. Physical and Chemical Properties of Some Selected Rice Varieties

    African Journals Online (AJOL)

    User

    Physical and chemical properties of nine rice varieties grown and processed in Ebonyi State were studied. Average ... values. Key words: Rice (Oryza sativa L); physical; chemical; mineral; vitamin; appearance ..... 30:670-. 684. Sanni S.A, Okeleye,K.A Soyode, A.F,Taiwo, O.C(2005) Physicochemical properties of early and.

  14. Seasonal variations in the growth duration of some rice varieties ...

    African Journals Online (AJOL)

    Two experiments were carried out in 2008 and 2009, in four locations in Cross State, to determine seasonal variations in the commonly grown rice varieties. Their response to different photoperiod treatments were investigated with rice plants in polyethylene bags subjected to varying lengths under artificial light.

  15. In vitro somatic embryogenesis of high yielding varieties of rice ...

    African Journals Online (AJOL)

    Rice (Oryza sativa L.) belongs to the family Gramineae and is the staple food for half of the world's population and occupies almost one-fifth of the total land area covered under cereals. Now-a-days, the production of rice is hampered due to climatic changes. Therefore, it is essential to develop variety which is tolerant to ...

  16. Factors Affecting the Adoption of Improved Rice Varieties in Borno ...

    African Journals Online (AJOL)

    USER

    The study investigated the factors that affect adoption of improved rice varieties in the .... It shares an international border with Cameroun to the east, Chad to the north- ..... The groups further pointed out that low market price and poor linkage.

  17. Factors Affecting the Adoption of Improved Rice Varieties in Borno ...

    African Journals Online (AJOL)

    USER

    interpreted using frequency table, percentage, chi-square and cluster analysis. .... analysis was used in testing the statistical significance of different hypothesised variables that may influence the adoption of improved rice varieties. Cluster .... decision of the farmers, however, inappropriate chain of supply/distributing the.

  18. Biophysical and Mechanical properties of rice varieties: attributes to ...

    African Journals Online (AJOL)

    The work showcases that at moisture content range (15 - 18%) wb, the compressive force against natural position of the grains were also determined and consideration of variation in natural position of rice grain at rest during compression gave representative apparent compressive strength across the five varieties.

  19. Allelopathic potential of selected rice varieties | Karim | African ...

    African Journals Online (AJOL)

    Average percent inhibition (API) in lettuce due to allelopathic effect of different rice varieties/lines was estimated. Under greenhouse conditions, double-pot technique was followed using barnyard grass (Echinochloa crusgalli L.) as indicator plant. The changes in barnyard grass plant charcters due to allelopathic effect of ...

  20. Agronomic performance of five rice varieties and nutritive value of ...

    African Journals Online (AJOL)

    Exp. 1), chemical composition and in vitro gas production (Exp. 2) of five varieties of rice; Hybrid, Exbaika, Jasmine 85, IR841 and Long grain ordinary 2. Experiment 1 was conducted in a randomized complete block design with four replicates ...

  1. Physical and Chemical Properties of Some Selected Rice Varieties ...

    African Journals Online (AJOL)

    Abstract. Physical and chemical properties of nine rice varieties grown and processed in Ebonyi State were studied. Average length and width of the tested varieties ranged between 6.31 and 7.63mm and 2.04 to 2.28mm respectively. All the grains are long grain but, Afikpo mars had the longest grain length of 7.63mm while ...

  2. IDENTIFICATION OF WIDE COMPATIBILITY VARIETIES IN SOME TROPICAL JAPONICA RICE

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    A. Hairmansis

    2013-07-01

    Full Text Available The F1 hybrid sterility in indica/japonica crosses is the major barrier in developing hybrid rice varieties between these two diverse germplasm. The sterility problem in japonica/indica hybrids can be overcome by using wide compatibility genes. The objective of this study was to identify wide compatibility varieties (WCVs in some tropical japonica rice. Twenty five tropical japonica varieties as male parents were crossed with indica (IR64 and japonica (Akitakomachi testers as female parents. The crosses were planted following a randomized complete block design with three replications. Varieties having average spikelet fertility of more than 70% with both the indica and japonica testers were rated as WCVs. Result from this study showed that six tropical japonica varieties were classified as WCVs, i.e., Cabacu, Grogol, Kencana Bali, Klemas, Lampung Lawer, and Napa. Hybrid sterility is caused by partial sterility of male and female gametes. The WCVs from the present study can be used in hybrid rice breeding program to solve hybrid sterility in indica/japonica hybrids.

  3. Coming to Grips with Farmers' variety Selection- the Case of New Improved Rice Varieties under Irrigation in South East Tanzania

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    Kafiriti, EM.

    2003-01-01

    Full Text Available In collaboration with farmers, rice varieties were evaluated under small-scale irrigation in two villages of south east Tanzania for two consecutive cropping seasons (1999/2000 –2000/2001. The objectives were to give farmers access to new improved rice varieties; to identify the selection criteria farmers consider important in irrigated rice production; and to come to grips with their arguments. Farmers were provided with eleven improved varieties, which they compared with their own ones. Farmers' preferred varieties with short to medium maturity period, which produce many tillers and mature uniformly; and with long translucent aromatic grains for their own use and marketing. This study identified qualitative and quantitative evaluation criteria which farmers are using for selecting rice varieties. The implication for further research on rice in south east Tanzania is that the breeding programme should incorporate these attributes to address farmers' preferences, rather than to go for absolute maximum yield levels.

  4. Effect of germination on the physicochemical and antioxidant characteristics of rice flour from three rice varieties from Nigeria.

    Science.gov (United States)

    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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Chemometric classification of pigmented rice varieties based on antioxidative properties in relation to color

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    Phaiwan Pramai

    2016-10-01

    Full Text Available The pigmented Thai rice varieties including red and black color and non-pigmented rice (white collected from different growth sites in the north of Thailand and were determined for color and antioxidant properties. Anthocyanins were the major compound in group of black rice (21.15-441.96 mg/100 g rice. Total phenolic, flavonoid, and -tocopherol contents were highest in the black rice followed by red rice and antioxidant capacities were predominant in pigmented varieties. Black rice grown in mountainous area presented the highest antioxidant activity compared to the other growing locations. The color parameters, especially L* value presented the negative correlations with antioxidant parameters, while the antioxidant contents, excepted -oryzanol content had significant correlation with antioxidant capacities. Pigmented rice varieties could be clearly classified into 4 groups using PCA and HCA, which provided a good indicator to classify pigmented rice varieties based on color and antioxidative properties.

  6. Agronomic evaluation of rain fed rice varieties in Seke - Banza area ...

    African Journals Online (AJOL)

    Six rain fed rice varieties from INERA (National Institute for Agronomic Study and Research) YANGAMBI center were cultivated at INERA GIMBI station. The objective was to get high yield rain fed rice varieties adapted to Seke-Banza area conditions in view to increase farmers' production and to reduce import of rice in the ...

  7. Effects of Variety and Fermentation Time on the Quality of Rice Wine ...

    African Journals Online (AJOL)

    A study was conducted to investigate the effect of variety and fermentation time on rice wine quality. Two rice varieties, X- Jigna and Gomera, and three fermentation times, 5, 6 and 7 days were used to study the physicochemical and sensory qualities of wine. Significant difference was observed at P<0.05 among the rice ...

  8. Effects of Chalkiness on Cooking, Eating and Nutritional Qualities of Rice in Two indica Varieties

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    Qi-hua Liu

    2009-06-01

    Full Text Available An experiment was conducted to investigate the effects of chalkiness on cooking, eating and nutrition qualities of rice using Gangyou 527 (indica hybrid rice and Zhaiyeqing 8 (conventional indica rice as materials. Compared with the milled rice without chalkiness, amylose content, final viscosity, setback and consistence increased significantly, while gel consistence, peak viscosity and breakdown decreased remarkably and other RVA values did not have significant changes in the chalky rice of Gangyou 527. The differences in the above indices between the chalky and non-chalky rice was not remarkable in Zhaiyeqing 8. The crude protein content of chalky rice in Zhaiyeqing 8 was significantly lower than that of non-chalky rice, but there was no remarkable change between the chalky and non-chalky rice in Gangyou 527. Glutelin content fell significantly, and albumin, globulin, prolamine and lysine contents did not change significantly in chalky rice compared with non-chalky rice in the two varieties.

  9. Changes in Rice Grain Quality of Indica and Japonica Type Varieties Released in China from 2000 to 2014.

    Science.gov (United States)

    Feng, Fan; Li, Yajun; Qin, Xiaoliang; Liao, Yuncheng; Siddique, Kadambot H M

    2017-01-01

    China is the first country to use heterosis successfully for commercial rice production. This study compared the main quality characteristics (head rice rate, chalky rice rate, chalkiness degree, gel consistency, amylose content, and length-to-width ratio) of 635 rice varieties (not including upland and glutinous rice) released from 2000 to 2014 to establish the quality status and offer suggestions for future rice breeding for grain quality in China. In the past 15 years, grain quality in japonica rice and indica hybrid rice has improved. In japonica rice, inbred varieties have increased head rice rates and decreased chalkiness degree over time, while hybrid rice varieties have decreased chalky rice rates and chalkiness degree. In indica hybrid rice, the chalkiness degree and amylose contents have decreased and gel consistency has increased. Improvements in grain quality in indica inbred rice have been limited, with some increases in head rice rate and decreases in chalky rice rate and amylose content. From 2010 to 2014, the percentage of indica varieties meeting the Grade III national standard of rice quality for different quality traits was low, especially for chalky rice rate and chalkiness degree. Japonica varieties have more superior grain quality than indica rice in terms of higher head rice rates and gel consistency, lower chalky rice rates and chalkiness degree, and lower amylose contents, which may explain why the Chinese prefer japonica rice. The japonica rice varieties, both hybrid and inbred, had similar grain qualities, but this varied in indica rice with the hybrid varieties having higher grain quality than inbred varieties due to significantly better head rice rates and lower chalkiness degree. For better quality rice in future, the chalky rice rate and chalkiness degree should be improved in japonica rice along with most of the quality traits in indica rice.

  10. Factors Affecting the Adoption and use of NERICA Varieties among Rice Producing Households in Ghana

    NARCIS (Netherlands)

    Asante, B.O.; Wiredu, A.N.; Dogbe, W.; Asuming-Boakye, A.; Nsiah Frimpong, B.; Haleegoah, J.

    2013-01-01

    This paper uses cross sectional data which were collected from 200 smallholder rice producers in Ghana, to examine the factors influencing the adoption and extent of use of NERICA rice varieties in Ghana. About 57.93 per cent of the sampled rice producers allocated 35.77 per cent of their land to

  11. Impact of Improved Rice Variety on Productivity Among Smallholder Farmers in Ghana

    Directory of Open Access Journals (Sweden)

    Edward Tsinigo

    2017-02-01

    Full Text Available Advancement in agricultural technologies is seen to result in the shift in production functions. The study was conducted to establish the impact of the improved rice variety on productivity in the Ejura-Sekyedumase and Atebubu-Amantin Municipalities of Ghana. The study was based on the survey of 208 rice farmers using a three-stage stratified sampling method. The study used a structured questionnaire to collect input-output data from the rice farmers. Data were analysed using the Cobb-Douglas production function. The study found that the technical change associated with the introduction of the improved rice variety was of the non-neutral type. Further, the adoption of the improved rice variety has increased rice productivity by about 46% for the adopters. The main determinants of productivity for the adopters were seed, land, fertiliser, herbicide, and education. Productivity among the non-adopters was positively influenced by seed, land, herbicide, and fertiliser. The study concluded that the improved rice variety has superior yield advantage. The study recommends for the simultaneous promotion of improved rice varieties and their recommended inputs to increase rice productivity.

  12. Interactions between the oomycete Pythium arrhenomanes and the rice root-knot nematode Meloidogyne graminicola in aerobic Asian rice varieties.

    Science.gov (United States)

    Verbeek, R E M; Banaay, C G B; Sikder, M; De Waele, D; Vera Cruz, C M; Gheysen, G; Höfte, M; Kyndt, Tina

    2016-12-01

    Aerobic rice fields are frequently infested by pathogenic oomycetes (Pythium spp.) and the rice root-knot nematode Meloidogyne graminicola. Here, the interaction between Pythium arrhenomanes and Meloidogyne graminicola was studied in rice roots of two aerobic rice varieties. In different experimental set-ups and infection regimes, plant growth, rice yield, Pythium colonization, as well as establishment, development and reproduction of M. graminicola were studied. In this study, it is shown that the presence of P. arrhenomanes delays the establishment, development and reproduction of M. graminicola compared to single nematode infected plants. The delay in establishment and development of M. graminicola becomes stronger with higher P. arrhenomanes infection pressure. Our data indicate that P. arrhenomanes antagonizes M. graminicola in the rice root and that the plant benefits from this antagonism as shown by the yield data, especially when either of the pathogens is present in high levels.

  13. Physico-chemical and cooking characteristics of some rice varieties

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    Rolando J. González

    2004-03-01

    Full Text Available Some physicochemical and cooking characteristics corresponding to different varieties and commercial samples of rice were analysed. Some mechanical properties determined by both, the viscoelastograf and the Instrom Universal Food Testing Machine were also analysed. Gelatinization time (Gt, gelatinization endotherm and amylose content were determined. The results showed that there was a very good correlation between gelatinization temperature and Gt, while no noticeable correlation among others phsycochemical characteristics was observed. Regarding the mechanical properties, both methods permited to show significant differences among most of the samples. However, when the samples order obtained with hardness (Instrom values was compared with that corresponding to firmness (Viscoelastograf values, some discrepancies were observed. This could be attributable to the number of grains and the cooking time used in each method. There was good linear correlation between hardness and amylose content. On the contrary, none of the viscoelastograf parameters are correlated well with amylose. An interesting point was that the slope of the regression line obtained between firmness and cooking time could be utilised as a measure of cooking resistance of each sample and was related to the rate of water absorption.Oito variedades e quatro amostras comerciais de arroz de boa qualidade foram analisadas com relação a algumas características físico-químicas e de cozimento. Algumas propriedades mecânicas foram avaliadas utilizando-se tanto o viscoamilógrafo como o equipamento Instron (Instron Universal Testing Machine, tais como, o tempo de gelatinização (Gt, a endoterma de gelatinização e o conteúdo de amilose. Os resultados mostraram que existe uma boa correlação entre a temperatura de gelatinização e Gt, contudo não foi observada correlação relevante entre outras características físico-químicas. Em relação às propriedades mecânicas, ambos

  14. Economic Performance of Traditional and Modern Rice Varieties under Different Water Management Systems

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    Manel Ben Hassen

    2017-02-01

    Full Text Available Italian rice production is progressively threatened by water scarcity. Some strategies have been developed to reduce water use. Nevertheless, reducing water irrigation amounts may lower paddy rice production. This publication compares the productivity and the economic performances of traditional and modern rice varieties in northern Italy using two different water management systems. The objective of this analysis is to enhance Italian rice cultivation at the economic, environmental and agronomic levels. Some positive variations of water productivity and economic water productivity were observed for the two varieties when using a lower amount of irrigation water. However, actual production costs and most water supply fees are the same for all the irrigation methods. Furthermore, the study of agronomic traits shows that during the recent years, there were no significant differences or increases of yield among varieties. Consequently, to be adopted by farmers, the irrigation costs coupled with improved rice accessions need to be optimized.

  15. Effect of fertiliser on functional properties of flour from four rice varieties grown in Sri Lanka.

    Science.gov (United States)

    Gunaratne, Anil; Sirisena, Nihal; Ratnayaka, Upul Kumari; Ratnayaka, Jennet; Kong, Xiangli; Vidhana Arachchi, Lal Peruma; Corke, Harold

    2011-05-01

    Fertiliser is an essential agro-chemical input in modern rice farming. Fertiliser affects the grain quality and yield of rice. Although much research has been carried out to investigate the influence of fertiliser (recommended NPK addition) on yield and quality of rice grain, little is known about the effect of fertiliser on thermal, pasting, gelling and retrogradation properties of rice flour. The aim of this study was to investigate the influence of recommended fertilisation on functional properties of rice flour from four popular high yielding rice varieties grown in Sri Lanka. Fertiliser (recommended NPK addition) increased the protein content but reduced the apparent amylose content in rice flour except in BG 357. Swelling power and amylose leaching were decreased by fertilizer. [corrected] Pasting onset temperature, cold paste viscosity and setback were increased but peak viscosity and granular breakdown decreased. In response to the fertiliser application, gelatinisation peak temperature was reduced in all varieties except BG 300. However, compared to pasting properties, gelatinisation parameters were not much affected by fertilisation. The extent of amylopectin retrogradation was decreased by fertiliser in BG 305 and BG 352 but unchanged in the other two varieties. Except in BG 305, fertiliser reduced the gel hardness of rice flour but increased the gel cohesiveness. It is apparent that the increased protein and reduced amylose content caused by fertiliser affect the functional properties of rice flour. Copyright © 2011 Society of Chemical Industry.

  16. Effect of rice variety on the physicochemical properties of the modified rice powders and their derived mucoadhesive gels.

    Science.gov (United States)

    Okonogi, Siriporn; Kaewpinta, Adchareeya; Khongkhunthian, Sakornrat; Yotsawimonwat, Songwut

    2015-06-01

    In the present study; the glutinous Niaw Sanpatong (NSP) and Niaw Koko-6 (NKK), and the non-glutinous Jasmine (JM) and Saohai (SH) were chemically modified. The difference of these rice varieties on the physicochemical characteristics of the modified rice powders and the properties of the derived gels were evaluated. X-ray diffractometer was used for crystalline structure investigation of the rice powders and gels. A parallel plate rheometer was used to measure the rheological property of the gels. It was found that the non-glutinous varieties produced gels with higher mucoadhesive properties than the glutinous rice. Rheological behavior of JM and SH gels was pseudoplastic without yield value whereas that of NSP and NKK gels was plastic with the yield values of 1077.4 ± 185.9 and 536.1 ± 45.8 millipascals-second (mPas), respectively. These different properties are considered to be due to the amylose content in different rice variety. The results suggest that the non-glutinous rice varieties with high amylose content are the most suitable for preparing gels as local delivery systems via the mucosal membrane.

  17. Adaptation of the brown planthopper, Nilaparvata lugens (Sta°l), to resistant rice varieties

    NARCIS (Netherlands)

    Ferrater, J.B.

    2015-01-01

    This thesis examines the three-way interaction between yeast-like symbionts, an insect herbivore [Nilaparvata lugens (Stål)] and its rice (Oryza sativa L.) host, during adaptation of the herbivore to resistant rice varieties. A long-term selection study (20 generations of continuous rearing,

  18. Dietary rice bran supplementation prevents salmonella colonization differentially across varieties and by priming intestinal immunity

    Science.gov (United States)

    The global burden of enteric dysfunction and diarrhoeal disease remains a formidable problem that requires novel interventions. This study investigated the immune-modulatory capacity of bran across rice varieties with phytochemical differences. 129SvEvTac mice were fed a 10% rice bran or control die...

  19. Physicochemical and sensory analysis of USA rice varieties developed for the basmati and jasmine markets

    Science.gov (United States)

    There is a steady demand for imported basmati and jasmine rice in The USA. Rice varieties that can be domestically produced and compete with these imports, have been developed from basmati, jasmine, and other aromatic germplasm sources. This study evaluated differences among eight USA aromatic varie...

  20. Different patterns of gene expression in rice varieties undergoing a ...

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... Phytopathology, 90: 415-421. Pierzynski J, O'Mara J, Tisserat N (2007). Diagnosing bacterial leaf streak of rice. National Plant Diagnostic Network, January 28-31,. Orlando, Florida. Quiroga M, Guerrero C, Botella MA, Barcelo A, Amaya I, Medina MI,. Alonso FJ, de Forchetti SM, Tigier H, Valpuesta V (2000).

  1. Evaluation of spectral reflectance of seven Iranian rice varieties canopies

    NARCIS (Netherlands)

    Darvishsefat, A.A.; Abbasi, M.; Schaepman, M.E.

    2011-01-01

    Rice cultivated areas and yield information is indispensable for sustainable management and economic policy making for this strategic food crop. Introduction of high spectral and special resolution satellite data has enabled production of such information in a timely and accurate manner. Knowledge

  2. DIFFUSION AND ADOPTION OF NEW RICE VARIETIES FOR AFRICA

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    Congress, Dares Salaam, Tanzania. 31 July–. 4 August, 2006. Adesina, A.A. and Baidu-Forson, J. 1995. Farmers'. Perceptions and Adoption of NewAgricultural. Technology: Evidence From Analysis in. Burkina Faso and Guinea,West Africa. Journal of Agricultural Economics 13:1-9. Africa Rice Center (WARDA)/FAO/SAA.

  3. Effect Of Shade Organic Materials And Varieties On Growth And Production Of Upland Rice

    Directory of Open Access Journals (Sweden)

    Jonatan Ginting

    2015-01-01

    Full Text Available Abstract There is a shade factor and low organic matter content of the soil is a problem that needs to be addressed in the development of upland rice cultivation as intercrops in the plantation area. Based on these considerations then one study that needs to be done is to conduct experiments on the effect of shade factor combined with the the provision of the organic material to the some varieties of upland rice that has been recommended nationally. The objective of experiment is to study the influence of shade organic materials and varieties on the growth and production of upland rice. This research using experimental design of Split - Split Plot Design with 3 treatment factors and 3 replications or blocks. The first factor is the treatment of shade with 3 levels shade percentage 0 20 and 40. The second factor is the dosage of organic material consists of 3 levels 0 g polybag 25 g polybag 50 g polybag and 75 g polybag. The third factor is the treatment of varieties consists of 4 types of upland rice varieties Si Kembiri Situ Patengggang Situ Bagendit and Tuwoti. The research results showed that the effect of shade on upland rice varieties decrease number of tillers number of panicles number of productive grains grain production per hill of uplnd rice plants and total sugar content of upland rice plants. Effect of organic matter increases number of panicles number of productive grains grain production per hill of upland rice plants and total sugar content of upland rice plants. It is known that the the variety of Situ Patenggang provides better growth and production compared with three other varieties Si Kembiri Situ Bagendit and Tuwoti in shaded conditions.

  4. Characterization of High-Value Bioactives in Some Selected Varieties of Pakistani Rice (Oryza sativa L.)

    Science.gov (United States)

    Zubair, Muhammad; Anwar, Farooq; Ashraf, Muhammad; Uddin, Md. Kamal

    2012-01-01

    The present study reports the composition and variation of fatty acids, sterols, tocopherols and γ-oryzanol among selected varieties namely Basmati Super, Basmati 515, Basmati 198, Basmati 385, Basmati 2000, Basmati 370, Basmati Pak, KSK-139, KS-282 and Irri-6 of Pakistani rice (Oryza sativa L). Oil content extracted with n-hexane from different varieties of brown rice seed (unpolished rice) ranged from 1.92% to 2.72%. Total fatty acid contents among rice varieties tested varied between 18240 and 25840 mg/kg brown rice seed. The rice tested mainly contained oleic (6841–10952 mg/kg) linoleic (5453–7874 mg/kg) and palmitic acid (3613–5489 mg/kg). The amounts of total phytosterols (GC and GC-MS analysis), with main contribution from β-sitosterol (445–656 mg/kg), campesterol (116–242 mg/kg), Δ5-avenasterol (89–178 mg/kg) and stigmasterol (75–180 mg/kg) were established to be 739.4 to 1330.4 mg/kg rice seed. The content of α-, γ- and δ-tocopherols as analyzed by HPLC varied from 39.0–76.1, 21.6–28.1 and 6.5–16.5 mg/kg rice seed, respectively. The amounts of different γ-oryzanol components (HPLC data), identified as cycloartenyl ferulate, 24-methylene cycloartanyl ferulate, campesteryl ferulate and β-sitosteryl ferulate, were in the range of 65.5–103.6, 140.2–183.1, 29.8–45.5 and 8.6–10.4 mg/kg rice seed, respectively. Overall, the concentration of these bioactives was higher in the Basmati rice cultivars showing their functional food superiority. In conclusion, the tested varieties of Pakistani rice, especially the Basmati cultivars, can provide best ingredients for functional foods. PMID:22605998

  5. Improvement of traditional local rice varieties through induced mutations using nuclear techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pham Van Ro; Do Huu At [Cuu Long Delta Rice Research Institute (Viet Nam)

    2001-03-01

    'Improvement of local rice varieties for high yield, resistance to disease and insect pests (brown plant hopper and rice blast) and export quality through induced mutations for the Mekong Delta' started in 1993. After six years, it showed effecting on the field in the MD as well as at the south of Vietnam. TNDB-100 manifest very wide adaptation and yield stable variety. THDB is suitable for deepwater rice region, coastal area, where rice cultivation effected by acid sulphate and salinity conditions. Both varieties are good example for the method. Thank to good Co-operation from extension center from provinces, hundred classes of extension were organized to recommend to the farmers. And thank to the strongly supporting from IAEA so that nearly 400,000 ha of TNDB-100 occupied at the south of Vietnam as well as nearly 15,000 ha of THDB grown in the coastal as well as rainfed lowland rice areas at the South of Vietnam. To continue the rice improvement by this technique, seeds of six traditional local varieties were exposed under different dose of gamma rays to create new mutants. At present day hundred improved breeding lines were selected, a dozen of uniform lines were isolated and entranced the yield trail as well as regional testing program. From these improved varieties would be selected to contribute to the rice cultivation at the south of Vietnam in the next years. (author)

  6. Online Variety Discrimination of Rice Seeds Using Multispectral Imaging and Chemometric Methods

    Science.gov (United States)

    Liu, W.; Liu, Ch.; Ma, F.; Lu, X.; Yang, J.; Zheng, L.

    2016-01-01

    Variety identification plays an important role in ensuring the quality and quantity of yield in rice production. The feasibility of a rapid and nondestructive determination of varieties of rice seeds was examined by using a multispectral imaging system combined with chemometric data analysis. Methods of the partial least squares discriminant analysis (PLSDA), principal component analysis-back propagation neural network (PCA-BPNN), and least squares-support vector machines (LS-SVM) were applied to classify varieties of rice seeds. The results demonstrate that clear differences among varieties of rice seeds could be easily visualized using the multispectral imaging technique and an excellent classification could be achieved combining data of the spectral and morphological features. The classification accuracy was up to 94% in a validation set with the LS-SVM model, which was better than the PLSDA (62%) and PCA-BPNN (84%) models.

  7. Classification of rice grain varieties arranged in scattered and heap fashion using image processing

    Science.gov (United States)

    Bhat, Sudhanva; Panat, Sreedath; N, Arunachalam

    2017-03-01

    Inspection and classification of food grains is a manual process in many of the food grain processing industries. Automation of such a process is going to be beneficial for industries facing shortage of skilled workforce. Machine Vision techniques are some of the popular approaches for developing such automations. Most of the existing works on the topic deal with identification of the rice variety by analyzing images of well separated and isolated rice grains from which a lot of geometrical features can be extracted. This paper proposes techniques to estimate geometrical parameters from the images of scattered as well as heaped rice grains where the grain boundaries are not clearly identifiable. A methodology based on convexity is proposed to separate touching rice grains in the scattered rice grain images and get their geometrical parameters. And in case of heaped arrangement a Pixel-Distance Contribution Function is defined and is used to get points inside rice grains and then to find the boundary points of rice grains. These points are fit with the equation of an ellipse to estimate their lengths and breadths. The proposed techniques are applied on images of scattered and heaped rice grains of different varieties. It is shown that each variety gives a unique set of results.

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

    Directory of Open Access Journals (Sweden)

    Shinta

    2014-05-01

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

  9. Mapping of a gene responsible for the difference in amylopectin structure between japonica-type and indica-type rice varieties.

    Science.gov (United States)

    Umemoto, T; Yano, M; Satoh, H; Shomura, A; Nakamura, Y

    2002-01-01

    The present investigation revealed that the alk and gel(t) genes, which cause the differences between a japonica rice variety Nipponbare and an indica rice variety Kasalath in terms of the disintegration of endosperm starch granules in alkali solution and their gelatinisation in a 4 M urea solution, respectively, cosegregated in backcross inbred lines derived from a cross between the two varieties. The segregation pattern of the profile for amylopectin chain-length, which was distinguished by enrichment in short chains of DPphysico-chemical properties of starch granules, and the gene was designated as acl(t). Gene-mapping analysis showed that the starch synthase IIa ( SSIIa) gene is located at the alk locus on chromosome 6 in the rice genome. These results lead us to the possibility that different alleles of the SSIIa gene are responsible for differences in amylopectin structure between the two varieties, in that SSIIa plays a distinct role in the elongation of short chains within clusters (A+B(1) chains) of amylopectin. It is proposed that the activity of SSIIa in japonica rice is reduced in amount or functional capacity relative to the activity of this enzyme in indica rice. This, in turn, would explain why starch from japonica rice has a lower gelatinisation temperature than starch from indica rice and is more susceptible to disintegration in alkali or urea. The evidence for this hypothesis is that the alk(t), gel(t), acl(t) and SSIIa genes all map to the same locus.

  10. [Glycemic index of two varieties of pasta and two varieties of rice].

    Science.gov (United States)

    Ridner, Edgardo; Di Sibio, Antonio

    2015-06-01

    The IG has been extensively studied as an indicator of the physiological effects of a carbohydrate meal with applications in the management and prevention of diabetes, dyslipidemia and obesity. A standard assay was performed to measure the glycemic index (GI) of two significant sources of carbohydrates following the World Health Organization (WHO) recommended methodology, determining the incremental area under the blood glucose response curve of a 50g carbohydrate portion of the test food compared to the same amount of carbohydrate from a glucose solution by the same subject measured in capillary whole blood before and 15, 30, 45, 60, 90 and 120 minutes after ingestion in a total of 9 subjects. The following results were obtained: Parboil rice: 73, Long Grain White Rice: 59; Pasta of durum wheat (Triticum durum): 71, Pasta of regular flour (Triticum aestivium): 38. This test confirms the low glycemic index of pasta made from durum wheat, and is the first measurement for pasta of common wheat flour properly characterized. It also indicates the values of the prevailing presentations of rice in the region, adding a reference for professionals and authorities.

  11. Comparative evaluation of mechanised and manual threshing options for Amankwatia and AGRA rice varieties in Ghana

    Directory of Open Access Journals (Sweden)

    Shadrack Kwadwo Amponsah

    2017-07-01

    Full Text Available Performance of a Yanmar DB 1000 mechanised paddy thresher was comparatively assessed against manual threshing by impact method using a locally-made wooden box for Amankwatia and AGRA rice varieties under farmer’s field conditions at Nobewam in the Ashanti Region of Ghana. The mechanised thresher was evaluated at various threshing drum speeds (550 rpm, 600 rpm and 650 rpm and feeding rates (200 kgh–1, 400 kgh–1 and 600 kgh–1. Results showed that threshing was satisfactory at grain moisture content between 16.9% w.b. and 18.0% w.b. for both rice varieties. Threshing efficiency increased from 94.6% to 95.8% with no significant difference observed whereas cleaning efficiency decreased significantly from 84.2% to 81.6% with increasing feed rate irrespective of rice variety. Again, threshing efficiency increased with increasing drum rotational speed, irrespective of feed rate and rice variety. Percentage broken grain and grain loss both increased with increasing peripheral drum speed and paddy feed rate irrespective of rice variety. Average fuel consumption, physical energy requirement and threshing capacity increased significantly with increasing drum speed and feed rate. Crop moisture content and shattering ability influenced the threshing efficiency, threshing capacity, grain loss, broken grain, fuel and physical energy requirement at threshing. AGRA rice variety generally performed better than Amankwatia under both mechanical and manually threshing methods. Mechanised threshing was significantly better at reducing grain loss and physical energy demand whilst yielding over 200% higher threshing capacity than manual threshing by impact using the wooden box. Mechanised threshing was financially rewarding, yielding over 500% higher profit margin than the manual threshing option. Further research on optimum crop moisture content for improved threshing of different rice varieties is suggested.

  12. Rice Yellow Mottle Virus stress responsive genes from susceptible and tolerant rice genotypes

    Directory of Open Access Journals (Sweden)

    Siré Christelle

    2008-03-01

    Full Text Available Abstract Background The effects of viral infection involve concomitant plant gene variations and cellular changes. A simple system is required to assess the complexity of host responses to viral infection. The genome of the Rice yellow mottle virus (RYMV is a single-stranded RNA with a simple organisation. It is the most well-known monocotyledon virus model. Several studies on its biology, structure and phylogeography have provided a suitable background for further genetic studies. 12 rice chromosome sequences are now available and provide strong support for genomic studies, particularly physical mapping and gene identification. Results The present data, obtained through the cDNA-AFLP technique, demonstrate differential responses to RYMV of two different rice cultivars, i.e. susceptible IR64 (Oryza sativa indica, and partially resistant Azucena (O. s. japonica. This RNA profiling provides a new original dataset that will enable us to gain greater insight into the RYMV/rice interaction and the specificity of the host response. Using the SIM4 subroutine, we took the intron/exon structure of the gene into account and mapped 281 RYMV stress responsive (RSR transcripts on 12 rice chromosomes corresponding to 234 RSR genes. We also mapped previously identified deregulated proteins and genes involved in partial resistance and thus constructed the first global physical map of the RYMV/rice interaction. RSR transcripts on rice chromosomes 4 and 10 were found to be not randomly distributed. Seven genes were identified in the susceptible and partially resistant cultivars, and transcripts were colocalized for these seven genes in both cultivars. During virus infection, many concomitant plant gene expression changes may be associated with host changes caused by the infection process, general stress or defence responses. We noted that some genes (e.g. ABC transporters were regulated throughout the kinetics of infection and differentiated susceptible and

  13. Microsatellite Markers in and around Rice Genes: Applications in Variety Identification and DUS Testing

    NARCIS (Netherlands)

    Bonow, S.; Pinho, Von E.V.R.; Vieira, M.G.C.; Vosman, B.

    2009-01-01

    In Brazil, rice (Oryza sativa L.) varieties adapted to different ecological regions are available on the market. However, these varieties exhibit highly similar morphologies, which makes their identification difficult. In this study we identified microsatellites in and around genes that are useful

  14. Response of high yielding rice varieties to NaCl salinity in ...

    African Journals Online (AJOL)

    Salinity is one the biggest constraint to obtain crop potential yield throughout paddy fields in some part of the coastal line of rice cultivated area in Iran. In order to find resistant varieties and study the reaction of some newly released high yielding varieties to different levels of salinity of irrigation water an experiment was ...

  15. Revealing different systems responses to brown planthopper infestation for pest susceptible and resistant rice plants with the combined metabonomic and gene-expression analysis.

    Science.gov (United States)

    Liu, Caixiang; Hao, Fuhua; Hu, Jing; Zhang, Weilin; Wan, Linglin; Zhu, Lili; Tang, Huiru; He, Guangcun

    2010-12-03

    Brown planthopper (BPH) is a notorious pest of rice plants attacking leaf sheaths and seriously affecting global rice production. However, how rice plants respond against BPH remains to be fully understood. To understand systems metabolic responses of rice plants to BPH infestation, we analyzed BPH-induced metabolic changes in leaf sheaths of both BPH-susceptible and resistant rice varieties using NMR-based metabonomics and measured expression changes of 10 relevant genes using quantitative real-time PCR. Our results showed that rice metabonome was dominated by more than 30 metabolites including sugars, organic acids, amino acids, and choline metabolites. BPH infestation caused profound metabolic changes for both BPH-susceptible and resistant rice plants involving transamination, GABA shunt, TCA cycle, gluconeogenesis/glycolysis, pentose phosphate pathway, and secondary metabolisms. BPH infestation caused more drastic overall metabolic changes for BPH-susceptible variety and more marked up-regulations for key genes regulating GABA shunt and biosynthesis of secondary metabolites for BPH-resistant variety. Such observations indicated that activation of GABA shunt and shikimate-mediated secondary metabolisms was vital for rice plants to resist BPH infestation. These findings filled the gap of our understandings in the mechanistic aspects of BPH resistance for rice plants and demonstrated the combined metabonomic and qRT-PCR analysis as an effective approach for understanding plant-herbivore interactions.

  16. Uptake and Distribution of Aluminum in Root Apices of Two Rice Varieties under Aluminum Stress

    Directory of Open Access Journals (Sweden)

    MIFTAHUDIN

    2007-09-01

    Full Text Available Aluminum (Al toxicity is the major limiting factor of plant growth and production in acid soils. The target of Al toxicity is the root tip, which affects mainly on root growth inhibition. The aim of this research was to study the uptake and distribution of Al in root apices of two rice varieties IR64 (Al-sensitive and Krowal (Al-tolerant, which were grown on nutrient solution containing 0, 15, 30, 45, and 60 ppm of Al. The root growth was significantly inhibited in both rice varieties at as low as 15 ppm Al concentration. The adventive roots of both varieties showed stunted growth in respons to Al stress. There was no difference in root growth inhibition between both rice varieties as well as among Al concentrations. Al uptake on root apices was qualitatively and quantitatively analyzed. Histochemical staining of roots using hematoxylin showed dark purple color on 1 mm region of Al-treated root apices. Rice var. IR 64 tended to take up more Al in root tip than Krowal did. However, there was no statistically significant difference (p = 0.176 in root Al content of both varieties in response to different concentration and period of Al treatments. Al distribution in root apices was found in the epidermal and subepidermal region in both rice varieties. Based on those results, rice var. Krowal that was previously grouped as Al-tolerant variety has similar root growth and physiological response to Al stress as compared to Al-sensitive variety IR64.

  17. Modern elite rice varieties of the 'Green Revolution' have retained a large introgression from wild rice around the Pi33 rice blast resistance locus.

    Science.gov (United States)

    Ballini, Elsa; Berruyer, Romain; Morel, Jean-Benoît; Lebrun, Marc-Henri; Nottéghem, Jean-Loup; Tharreau, Didier

    2007-01-01

    During the breeding process of cultivated crops, resistance genes to pests and diseases are commonly introgressed from wild species. The size of these introgressions is predicted by theoretical models but has rarely been measured in cultivated varieties. By combining resistance tests with isogenic strains, genotyping and sequencing of different rice accessions, it was shown that, in the elite rice variety IR64, the resistance conferring allele of the rice blast resistance gene Pi33 was introgressed from the wild rice Oryza rufipogon (accession IRGC101508). Further characterization of this introgression revealed a large introgression at this locus in IR64 and the related variety IR36. The introgressed fragment represents approximately half of the short arm of rice chromosome 8. This is the first report of a large introgression in a cultivated variety of rice. Such a large introgression is likely to have been maintained during backcrossing only if a selection pressure was exerted on this genomic region. The possible traits that were selected are discussed.

  18. Susceptibility of glutinous rice starch to digestive enzymes.

    Science.gov (United States)

    Guo, Li; Zhang, Juanjuan; Hu, Jian; Li, Xueling; Du, Xianfeng

    2015-09-05

    To understand the susceptibility of glutinous rice starch to digestive enzymes and its potential impact on glycemic response, enzyme kinetics and in vitro digestibility of the native and gelatinized starches were investigated. The results showed that the Km values of the native and gelatinized starch were 10.35 mg/mL and 9.92 mg/mL, respectively. The digestion rate coefficients k values of the native and gelatinized starches were 2.0 × 10(-3)min(-1) and 1.1 × 10(-2)min(-1), respectively. The contents of rapid digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) in native glutinous rice starch were 8.92%, 21.52% and 69.56%, respectively. After gelatinization, the amounts of RDS, SDS and RS were 18.47%, 29.75% and 51.78%, respectively. The native and gelatinized glutinous rice starches were 10.34% and 14.07% for hydrolysis index (HI), as well as 43.14% and 45.92% for glycemic index (GI), respectively. During the in vitro digestion, the crystallinity of native glutinous rice starch was increased from 34.7% to 35.8% and 38.4% after 20 and 120 min, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Factors Affecting the Adoption of Improved Rice Varieties in Borno ...

    African Journals Online (AJOL)

    Farmer's groups also mentioned that lack of a medium maturing variety and a thresher are amongst their most important problems. This challenges present implication for developing different technologies and support system that take such variance in to account or government will keep on spending a huge resources that ...

  20. Marker-assisted breeding of Indonesia local rice variety Siputeh for semi-dwarf phonetype, good grain quality and disease resistance to bacterial blight.

    Science.gov (United States)

    Luo, Yanchang; Zakaria, Sabaruddin; Basyah, Bakhtiar; Ma, Tingchen; Li, Zefu; Yang, Jianbo; Yin, Zhongchao

    2014-12-01

    Rice is one of the most important staple food crops in Asia. Since the first green revolution beginning in 1960s, high-yield semidwarf modern rice varieties have been widely planted; however, traditional rice varieties with tall plant type are still grown in many countries due to their good grain quality and adaptation to local climate and environment. Siputeh, a local rice variety mainly planted in Java and Sumatra islands of Indonesia, produces long grain rice with good cooking and eating quality. However, the variety has low yield with tall plant type and long growth duration and is highly susceptible to biotic and abiotic stress. Siputeh as the recurrent female was crossed with the donor line WH421, an elite paternal line of hybrid rice containing the sd1, Wx (b), Xa4 and Xa21 genes, followed by backcrossing and self-pollination. TS4, a BC3F4 line derived from the breeding program, was obtained through marker-assisted selection for the sd1, Wx (b), Xa4 and Xa21 loci. TS4 has semi-dwarf phenotype and short growth duration. TS4 conferred disease resistance to multiple Xanthomonas oryzae pv. oryzae (Xoo) strains collected from different countries around the world. TS4 achieved higher grain yield than Siputeh in two field trials conducted in Banda Aceh, Indonesia and Lingshui, China, respectively. Finally, TS4 has better grain quality than Siputeh in terms of degree of chalkiness and amylose content. An improved rice line, designed as TS4, has been developed to contain semi-dwarf gene sd1, low amylase content gene Wx (b) and bacterial light resistance genes Xa4 and Xa21 through marker-assisted selection. TS4 has semi-dwarf phenotype with reduced growth duration, produces high yield with good grain quality and provides broad-spectrum resistance to Xoo strains. The development of TS4 enriches the diversity of local rice varieties with high yield potential and good grain quality.

  1. Identification of Heading Date Six (Hd6 Gene Derived from Rice Mutant Varieties

    Directory of Open Access Journals (Sweden)

    Aryanti Aryanti

    2017-04-01

    Full Text Available Genes which were associated with flowering time to indicate the early maturity is known as heading date (Hd. Heading date six (Hd6 gene was identified from rice mutant varieties were Atomita 2, Atomita 3, Atomita 4, Bestari, Cilosari, Diah Suci, Sidenuk, Kahayan, Mayang, Meraoke, Mira-1, Pandan Putri, Superwin, Suluttan Unsrat 1, Suluttan Unsrat 2, Winongo, Woyla, Yuwono, while the rice var. Nipponbare was used as a positive control. All of rice mutant varieties derived from mutation induction by the dose of 0.2 kGy. The aim of this experiment was to find out the data base of mutant varieties which could be used as parent material with earlier maturity trait genetically. To obtain the DNA of plants, young leaves of each variety were extracted by liquid nitrogen, and then lysis and extracted by Kit Plant Genomic DNA. The amplification of DNA with 7 primers of Hd6 conducted of 40 cycles by PCR and were continues to separated by 1 % agarose. The results were shown that the rice Mira-1 and Bestari varieties obtained from mutation of Cisantana highly different from one to another on 7 primers of Hd6 used. Mayang variety from mutation of cross breeding between Cilosari and IR64, Pandan putri from Pandan wangi and Woyla from mutation of cross breeding from Atomita 2 and IR64 were highly different with those of their parents. Identification of Hd6 gene on Sidenuk variety was shown the same bands pattern with Nipponbare as control positive toward all primers used, this variety would be better for earlier maturity parent material compared to others. The information could be useful for breeding programs aiming to develop early maturing widely adaptive and high yielding rice cultivars.

  2. A resistance locus in the American heirloom rice variety Carolina Gold Select is triggered by TAL effectors with diverse predicted targets and is effective against African strains of Xanthomonas oryzae pv. oryzicola

    OpenAIRE

    Triplett, Lindsay R.; Cohen, Stephen P.; Heffelfinger, Christopher; Clarice L Schmidt; Huerta, Alejandra; Tekete, Cheick; Verdier, Valerie; Bogdanove, Adam J.; Jan E. Leach

    2016-01-01

    The rice pathogens Xanthomonas oryzae pathovar (pv.) oryzae and pv. oryzicola produce numerous transcription activator-like (TAL) effectors that increase bacterial virulence by activating expression of host susceptibility genes. Rice resistance mechanisms against TAL effectors include polymorphisms that prevent effector binding to susceptibility gene promoters, or that allow effector activation of resistance genes. This study identifies, in the heirloom variety Carolina Gold Select, a third m...

  3. Susceptibility Of Five Cowpea ( Vigna unguiculata ) Varieties To ...

    African Journals Online (AJOL)

    Each variety was placed in a plastic bag and kept in a freezer at -5oC for 24 hours to eliminate C. maculatus infestations coming from the field. Two hundred grammes of each cowpea variety was placed in a glass container and each infested with a male and female C. maculatus that were reared in the laboratory. The set up ...

  4. Genetic diversity trend in Indian rice varieties: an analysis using SSR markers.

    Science.gov (United States)

    Singh, Nivedita; Choudhury, Debjani Roy; Tiwari, Gunjan; Singh, Amit Kumar; Kumar, Sundeep; Srinivasan, Kalyani; Tyagi, R K; Sharma, A D; Singh, N K; Singh, Rakesh

    2016-09-05

    The knowledge of the extent and pattern of diversity in the crop species is a prerequisite for any crop improvement as it helps breeders in deciding suitable breeding strategies for their future improvement. Rice is the main staple crop in India with the large number of varieties released every year. Studies based on the small set of rice genotypes have reported a loss in genetic diversity especially after green revolution. However, a detailed study of the trend of diversity in Indian rice varieties is lacking. SSR markers have proven to be a marker of choice for studying the genetic diversity. Therefore, the present study was undertaken with the aim to characterize and assess trends of genetic diversity in a large set of Indian rice varieties (released between 1940-2013), conserved in the National Gene Bank of India using SSR markers. A set of 729 Indian rice varieties were genotyped using 36 HvSSR markers to assess the genetic diversity and genetic relationship. A total of 112 alleles was amplified with an average of 3.11 alleles per locus with mean Polymorphic Information Content (PIC) value of 0.29. Cluster analysis grouped these varieties into two clusters whereas the model based population structure divided them into three populations. AMOVA study based on hierarchical cluster and model based approach showed 3 % and 11 % variation between the populations, respectively. Decadal analysis for gene diversity and PIC showed increasing trend from 1940 to 2005, thereafter values for both the parameters showed decreasing trend between years 2006-2013. In contrast to this, allele number demonstrated increasing trend in these varieties released and notified between1940 to 1985, it remained nearly constant during 1986 to 2005 and again showed an increasing trend. Our results demonstrated that the Indian rice varieties harbors huge amount of genetic diversity. However, the trait based improvement program in the last decades forced breeders to rely on few parents, which

  5. Effect of three water treatments on growth of rice variety IR36 ...

    African Journals Online (AJOL)

    Rice (Oryza Sativa L.) variety IR36 was grown under three water treatments namely: saturated sand, water table held at 15cm below the sand surface and water table at 30 cm below the sand surface. The growth period was 6 weeks with plants harvested at two week intervals. Growth parameters measured included total ...

  6. Response to different rates of nitrogen by five varieties of swamp rice

    African Journals Online (AJOL)

    A field experiment was conducted in 2011 and 2012 in Ini Local Government Area of Akwa Ibom State, Nigeria; mainly to determine the optimum nitrogen fertilizer rate for the area as well as select the rice varieties that responded optimally. A split plot design was used with five N rates (0, 50, 100, 150and 200kg/ha) as the ...

  7. Site Suitability Analysis for Dissemination of Salt-tolerant Rice Varieties in Southern Bangladesh

    Science.gov (United States)

    Sinha, D. D.; Singh, A. N.; Singh, U. S.

    2014-11-01

    Bangladesh is a country of 14.4 million ha geographical area and has a population density of more than 1100 persons per sq. km. Rice is the staple food crop, growing on about 72 % of the total cultivated land and continues to be the most important crop for food security of the country. A project "Sustainable Rice Seed Production and Delivery Systems for Southern Bangladesh" has been executed by the International Rice Research Institute (IRRI) in twenty southern districts of Bangladesh. These districts grow rice in about 2.9 million ha out of the country's total rice area of 11.3 million ha. The project aims at contributing to the Government of Bangladesh's efforts in improving national and household food security through enhanced and sustained productivity by using salinity-, submergence- and drought- tolerant and high yielding rice varieties. Out of the 20 project districts, 12 coastal districts are affected by the problem of soil salinity. The salt-affected area in Bangladesh has increased from about 0.83 million ha in 1973 to 1.02 million ha in 2000, and 1.05 million ha in 2009 due to the influence of cyclonic storms like "Sidr", "Laila" and others, leading to salt water intrusion in croplands. Three salinity-tolerant rice varieties have recently been bred by IRRI and field tested and released by the Bangladesh Rice Research Institute (BRRI) and Bangladesh Institute of Nuclear Agriculture (BINA). These varieties are BRRI dhan- 47 and Bina dhan-8 and - 10. However, they can tolerate soil salinity level up to EC 8-10 dSm-1, whereas the EC of soils in several areas are much higher. Therefore, a large scale dissemination of these varieties can be done only when a site suitability analysis of the area is carried out. The present study was taken up with the objective of preparing the site suitability of the salt-tolerant varieties for the salinity-affected districts of southern Bangladesh. Soil salinity map prepared by Soil Resources Development Institute of

  8. HYPOGLYCEMIC ACTIVITY OF SOME INDONESIAN RICE VARIETIES AND THEIR PHYSICOCHEMICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Sri Widowati

    2016-10-01

    Full Text Available Diabetes mellitus is a spectrum of inherited and acquired disorders characterized by elevating blood glucose levels. Diabetes is an abnormal carbohydrate metabolism, therefore, diet therapy for diabetics plays a key role in the management of the disease. Most Indonesian people consume rice as source of energy and protein. Generally, diabetics consume very limited rice because they believe that rice is the one of hyperglycemic food, even though different rice varieties have large range of glycemic index. The study aimed to evaluate hypoglycemic properties by using rat assay and chemical characteristics of 10 Indonesian rice varieties, i.e. Pandan Wangi, Rojolele, Bengawan Solo, Cenana Bali, Memberamo, Celebes, Ciherang, Batang Piaman, Cisokan, and Lusi. Taj Mahal, an herbal ponni imported rice, was used as a comparison. Male Sprague Dawley rats (150- 200 g body weight were used for hypoglycemic assay. The rats were fasted overnight before the blood glucose was measured in the morning. The rats were then feed with 4.5 g rice per kg body weight by oral administration, followed by 1 ml of 10% glucose solution in the next 30 minutes. The blood glucose was measured for the next 30, 60, 90, and 120 minutes. Changes in blood glucose concentrations (mg dl-1 before and after the oral administrations were calculated for each rice variety tested. Results showed that Cisokan and Batang Piaman were categorized as low glycemic responses and Ciherang as high glycemic response, while the other varieties (Memberamo, Cenana Bali, Lusi, Bengawan Solo, Pandan Wangi, Celebes, and Rojo Lele showed moderate glycemic responses. As the best hypoglycemic activity, Cisokan contained high amylose (27.6%, fat (0.87%, total dietary fiber (6.24%, resistant starch (2.02%, and lowest starch digestibility (52.2%, which are ideal for diabetic’s consumption. Ciherang as the worst hypoglycemic activity had low resistant starch (1.78%, low total dietary fiber (4.52%, and medium

  9. Genetic parameters estimation on functional dryness traits of crossed black paddy rice "Baas Selem Cultivar X Situ Patenggang” variety

    Directory of Open Access Journals (Sweden)

    I.G.P.M. Aryana

    2014-07-01

    Full Text Available The aims of this study were to elucidate heritability and the role of drought traits genes of black paddy rice for determination base of the selection method to obtain drought tolerant and high yield potential of black paddy rice. The study was conducted through two experiments during February-November 2013. The first experiment was the establishment of populations from crosses carried out in the hybridization room. The second trial was evaluation of the genetic diversity of drought properties held in the greenhouse of the Faculty of Agriculture, University of Mataram. Planting was carried out in pots without experiment design. Population of P1 (parental-Situ Patenggang, P2 (parental-Baas Selem were 50 plants of each; population of F1, F1BC.1.2, and F1BC.1.1 were 25 plants of each, and 250 plants of F2, as well as control of drought susceptible variety (IR20 was 10 plants. To determine the heritability and the role of genes controlling drought traits were used index of bud dry and cure of IRRI standard. The results showed that crossing of black paddy rice "Baas Selem x Situ Patenggang” had relatively moderate heritability in broad sense and low heritability in narrow sense. In the crossed F1 population was found that gene action of drought trait was not perfectly dominant

  10. The effect of alternate wetting and drying on methane fluxes on different varieties of European rice

    Science.gov (United States)

    Oliver, Viktoria; Cochrane, Nicole; Monaco, Stefano; Volante, Andrea; Orasen, Gabriele; Price, Adam; Arn Teh, Yit

    2017-04-01

    In Europe, rice is grown (467 000 ha) under permanently flooded conditions (PF) using irrigation waters of major rivers. Climate change, which has led to a greater fluctuation in river flows, is a major challenge to rice production systems, which depend on large and consistent water supplies. This challenge will become more acute in the future, with more frequent extreme weather (e.g. drought) predicted under climate change and increased demands for rice. Alternate wetting and drying (AWD) is a system in where irrigation is applied to obtain 2-5 cm of field water depth, after which the soil is allowed to drain naturally to typically 15 cm below the surface before re-wetting once more. Preliminary studies suggest that AWD can reduce water use by up 30 %, with no net loss in yield but significantly reducing CH4 emissions. The work presented here evaluated the impacts of AWD on the productivity and yield of twelve varieties of European rice, whilst simultaneously measuring CH4 fluxes and plant biomass allocation patterns under different treatment regimes. Field experiments were conducted in the Piedmont region (northern Italy Po river plain) in a loamy soil during the growing season of 2015 in a 2-factor paired plot design, with water treatment (AWD, PF) and variety (12 European varieties) as factors (n=4 per variety per treatment). The varieties chosen were commercially important cultivars from across the rice growing regions of Europe (6 Italian, 3 French, 3 Spanish). Greenhouse gas fluxes were taken using the static chamber approach 11 times during the growing season between May and October 2015. Environmental variables (soil moisture, temperature, water table depth, water potential) were collected concomitantly. Above and belowground biomass were determined by destructively harvesting at the end of the growing season. Belowground biomass was estimated by manually extracting roots from 30 cm deep soil cores and aboveground biomass estimated by collecting and

  11. Elemental analysis of different varieties of rice samples using XRF technique

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Jaspreet, E-mail: gillpreet05051812@gmail.com; Kumar, Anil, E-mail: gilljaspreet06@gmail.com [Department of Basic and Applied Physics, Punjabi University, Patiala 147002 (India)

    2016-05-06

    Rice is most consumed staple food in the world providing over 21% of the calorie intake of world’s population having high yielding capacity. Elements detected in rice are Al, As, Br, Cd, Cl, Co, Cs, Cu, Fe, Hg, K, Mg, Mn, Mo, Rb, Se and Zn by using Instrumental Neutron Activation with k0 standardization (R. Jayasekera etal,2004). Some of these trace elements are C, H, O, N, S, Ca, P, K, Na, Cl, Mn, Ti, Mg, Cu, Fe, Ni, Si and Zn are essential for growth of human physique The deficiency or excess of these elements in food is known to cause a variety of malnutrition or health disorders in the world. Every year, various varieties of rice are launched by Punjab Agriculture University, Ludhiana. The main purpose of which is to increases the yield to attain the maximum profit. But this leads to changing the elemental concentration in them, which may affect the human health according to variation in the nutrition values. The main objective is to study the presence of elemental concentration in various varieties of rice using EDXRF technique.

  12. Antioxidant potential of brans of twenty-nine red and white rice (Oryza sativa L. varieties of Sri Lanka

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    Walimuni Kanchana Subhashini Mendis Abeysekera

    2017-11-01

    Full Text Available Objective: To evaluate antioxidant properties of brans of twenty-nine red and white rice varieties of Sri Lanka. Methods: Brans of 21 new improved (NI, 2 old improved (OI and 6 traditional red and white rice varieties of Sri Lanka were studied for range of antioxidant properties. The studied antioxidant properties included total polyphenolic content (TPC, ferric reducing antioxidant power (FRAP, oxygen radical absorbance capacity (ORAC, 2,2’-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid (ABTS radical scavenging activity and 1,1-diphenyl- 2-picrylhydrazine (DPPH radical scavenging activity in vitro. Bran of black rice variety from Korea was also studied for the same antioxidant properties for comparison. Results: Results exhibited significantly high ABTS and DPPH radical scavenging activities and 10, 7 and 2.5 fold greater TPC, FRAP and ORAC activities in brans of red rices (BRRs compared to brans of white rices irrespective of NI, OI and traditional rice types. Among BRRs traditional varieties had greater ABTS and DPPH radical scavenging activities and 1.7, 1.3 and 1.2 fold respectively greater TPC, FRAP and ORAC in contrast to NI red rices. Traditional red rice varieties, Kalu Heeneti (TPC and ORAC, Pachchaperumal (TPC and DPPH and Kurulu Thuda (DPPH and OI red rice variety H4 (FRAP exhibited the highest activities for the antioxidant properties studied. Further, these varieties had significantly high activities compared to black rice. Conclusions: In conclusion, BRRs especially traditional red rices had greater antioxidant properties and consumption may be useful in managing various chronic diseases.

  13. Impact of Water Management on Rice Varieties, Yield, and Water Productivity under the System of Rice Intensification in Southern Taiwan

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    Victoriano Joseph Pascual

    2016-12-01

    Full Text Available The system of rice intensification (SRI uses less water and enhances rice yield through synergy among several agronomic management practices. This claim was investigated to determine the effects of crop growth, yield and irrigation water use, using two thirds of the recommended SRI practices and two rice varieties, namely Tainan11 (TN11 and Tidung30 (TD30. Irrigation regimes were (a intermittent irrigation with three-day intervals (TD303 and TN113; (b intermittent irrigation with seven-day intervals (TD307 and TN117 and (c continuous flooding (TD30F and TN11F. Results showed that intermittent irrigation of three- and seven-day intervals produced water savings of 55% and 74% compared with continuous flooding. Total water productivity was greater with intermittent irrigation at seven-day intervals producing 0.35 kg·grain/m3 (TN117 and 0.46 kg·grain/m3 (TD307. Average daily headed panicle reduced by 166% and 196% for TN113 and TN117 compared with TN11F, with similar reduction recorded for TD303 (150% and TD307 (156% compared with TD30F. Grain yield of TD30 was comparable among irrigation regimes; however, it reduced by 30.29% in TN117 compared to TN11F. Plant height and leaf area were greater in plants exposed to intermittent irrigation of three-day intervals.

  14. Salt Tolerant and Sensitive Rice Varieties Display Differential Methylome Flexibility under Salt Stress

    Science.gov (United States)

    Ferreira, Liliana J.; Azevedo, Vanessa; Maroco, João; Oliveira, M. Margarida; Santos, Ana Paula

    2015-01-01

    DNA methylation has been referred as an important player in plant genomic responses to environmental stresses but correlations between the methylome plasticity and specific traits of interest are still far from being understood. In this study, we inspected global DNA methylation levels in salt tolerant and sensitive rice varieties upon salt stress imposition. Global DNA methylation was quantified using the 5-methylcytosine (5mC) antibody and an ELISA-based technique, which is an affordable and quite pioneer assay in plants, and in situ imaging of methylation sites in interphase nuclei of tissue sections. Variations of global DNA methylation levels in response to salt stress were tissue- and genotype-dependent. We show a connection between a higher ability of DNA methylation adjustment levels and salt stress tolerance. The salt-tolerant rice variety Pokkali was remarkable in its ability to quickly relax DNA methylation in response to salt stress. In spite of the same tendency for reduction of global methylation under salinity, in the salt-sensitive rice variety IR29 such reduction was not statistically supported. In ‘Pokkali’, the salt stress-induced demethylation may be linked to active demethylation due to increased expression of DNA demethylases under salt stress. In ‘IR29’, the induction of both DNA demethylases and methyltransferases may explain the lower plasticity of DNA methylation. We further show that mutations for epigenetic regulators affected specific phenotypic parameters related to salinity tolerance, such as the root length and biomass. This work emphasizes the role of differential methylome flexibility between salt tolerant and salt sensitive rice varieties as an important player in salt stress tolerance, reinforcing the need to better understand the connection between epigenetic networks and plant responses to environmental stresses. PMID:25932633

  15. Salt Tolerant and Sensitive Rice Varieties Display Differential Methylome Flexibility under Salt Stress.

    Directory of Open Access Journals (Sweden)

    Liliana J Ferreira

    Full Text Available DNA methylation has been referred as an important player in plant genomic responses to environmental stresses but correlations between the methylome plasticity and specific traits of interest are still far from being understood. In this study, we inspected global DNA methylation levels in salt tolerant and sensitive rice varieties upon salt stress imposition. Global DNA methylation was quantified using the 5-methylcytosine (5mC antibody and an ELISA-based technique, which is an affordable and quite pioneer assay in plants, and in situ imaging of methylation sites in interphase nuclei of tissue sections. Variations of global DNA methylation levels in response to salt stress were tissue- and genotype-dependent. We show a connection between a higher ability of DNA methylation adjustment levels and salt stress tolerance. The salt-tolerant rice variety Pokkali was remarkable in its ability to quickly relax DNA methylation in response to salt stress. In spite of the same tendency for reduction of global methylation under salinity, in the salt-sensitive rice variety IR29 such reduction was not statistically supported. In 'Pokkali', the salt stress-induced demethylation may be linked to active demethylation due to increased expression of DNA demethylases under salt stress. In 'IR29', the induction of both DNA demethylases and methyltransferases may explain the lower plasticity of DNA methylation. We further show that mutations for epigenetic regulators affected specific phenotypic parameters related to salinity tolerance, such as the root length and biomass. This work emphasizes the role of differential methylome flexibility between salt tolerant and salt sensitive rice varieties as an important player in salt stress tolerance, reinforcing the need to better understand the connection between epigenetic networks and plant responses to environmental stresses.

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

    Science.gov (United States)

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

    2008-02-15

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

  17. Resistant Starch: Variation among High Amylose Rice Varieties and Its Relationship with Apparent Amylose Content, Pasting Properties and Cooking Methods

    Science.gov (United States)

    Resistant starch (RS), which is not hydrolyzed in the small intestines, has proposed health benefits. We evaluated a set of 40 high amylose rice varieties for RS levels in cooked rice and approximately a 1.9-fold difference was found. The highest ones had more than two-fold greater RS concentration ...

  18. Development of New Submergence Tolerant Rice Variety for Bangladesh Using Marker-Assisted Backcrossing

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    Khandakar Md Iftekharuddaula

    2015-01-01

    Full Text Available Submergence tolerant high yielding rice variety was developed using BR11 as a recipient parent applying foreground, phenotypic and background selection approaches. Recombinant selection was found essential to minimize linkage drag by BC2F2 generation. Without recombinant selection, the introgression size in the backcross recombinant lines (BRLs was approximately 15 Mb on the carrier chromosome. The BRLs were found submergence tolerance compared to the check varieties under complete submergence for two weeks at Bangladesh Rice Research Institute, and produced higher yield compared to the isogenic Sub1-line under controlled submerged condition. The BRL IR85260-66-654-Gaz2 was released as BRRI dhan52 in 2010, which was the first high yielding submergence tolerant variety in Bangladesh. BRRI dhan52 produced grain yield ranging from 4.2 to 5.2 t/hm2 under different flash flood prone areas of Bangladesh in three consecutive seasons. The study demonstrated the efficiency of recombinant selection and better adaptability of the newly released submergence tolerant high yielding variety in flash flood prone different areas of the country with respect to submergence tolerance and yield potential.

  19. Factors Affecting Adoption of Improved Rice Varieties among Rural Farm Households in Central Nepal

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    Raju Ghimire

    2015-01-01

    Full Text Available The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop season, we performed a probit model (plot-level analysis to determine the probability of adopting new improved rice varieties (NIRVs by smallholder farmers particularly from two main agro-ecological regions (hills and tropical plain terai regions of Central Nepal. The results revealed that education, extension services and seed access play significant roles in adoption decisions. Additionally, farm and field characteristic variables such as farm size, endowment of favorable land type (e.g. lowlands, and animal power (e.g. oxen are the key factors influencing the probability of adopting NIRVs. The results showed that technology specific variables (e.g. yield potential and acceptability are significant for explaining adoption behavior, implying that it is important to take farmers’ preferences to varietal characteristics into consideration in the design of a research and development program. Given the significant role played by extension and access related variables, increased emphasis on information dissemination, field demonstration, and farmers’ participatory research and training programs to popularize new rice varieties and enhance their adoption rate are required. This also suggests that policy intervention should be made on improving the educational status of farming households, and developing programs on varietal package of rice seed which offer farmers a variety of choices among the appropriate pools of germplasm. Such programs ultimately help farmers develop more profit-oriented behavior which are necessary to enhance adoption rate, production and food security in the long run.

  20. Genetic Diversity Analysis of Traditional Rice Variety Pachchaperumal Using SSR Markers

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    Warusawithana T.M

    2017-08-01

    Full Text Available Assessing the genetic diversity for miniaturization of crop collections to form mini core collection will lead to greater utilization of germplasm to develop improved crop cultivars along with effective maintenance of it. It has become vital to perform this for traditional Rice Oryza sativa L. varieties when considering the arising demand for their qualities. This study was conducted to assess the genetic diversity of twenty Pachchaperumal traditional Rice accessions with two control varieties Bg360 and Suwandal Rice conserved at the Seed Genebank of Plant Genetic Resources Center Gannoruwa Sri Lanka. Morphological analysis was done using seven standard seed morphological descriptors of Rice and Molecular analysis was done using 16 SSR primers. Statistical analysis was done for morphological and molecular data using MINITAB 15 and POPGENE 1.31 softwares respectively. Strategy of bulking accessions was tested in this study relying on seed morphological clustering and those bulks were used in the molecular analysis. Results revealed a significant degree of genetic diversity among tested accessions both morphologically and molecularly and molecular results were more contributive. Two distinct accessions were identified as potential off types of Pachchaperumal accession numbers 3752 and 5547. Cluster analysis based on morphological traits generated seven major clusters at 1.62 relative distance. Depending on the pattern of clustering ten bulks were formed. The molecular analysis based on bulks generated five clusters in a relative genetic distance of 9.0. Eleven accessions were distinguished as representative set out of all 20 accessions and according to passport data 3 of them were Bg accessions 5550 5549 and 5546.

  1. Relative susceptibilities of five fodder radish varieties (Raphanus sativus var. Oleiformis) to Meloidogyne chitwoodi

    NARCIS (Netherlands)

    Teklu, M.G.; Schomaker, C.H.; Been, T.H.

    2014-01-01

    The fodder radish varieties Anaconda, Contra, Defender, Doublet and Terranova, known to have some partial resistance, were compared to the standard variety, Radical, to estimate their relative susceptibility (RS) for both population dynamic parameters of Meloidogyne chitwoodi and to evaluate Pi

  2. ISSR markers based on GA and AG repeats reveal genetic relationship among rice varieties tolerant to drought, flood, or salinity.

    Science.gov (United States)

    Reddy, Ch Surendhar; Babu, A Prasad; Swamy, B P Mallikarjuna; Kaladhar, K; Sarla, N

    2009-02-01

    Drought, flood, salinity, or a combination of these limits rice production. Several rice varieties are well known for their tolerance to specific abiotic stresses. We determined genetic relationship among 12 rice varieties including 9 tolerant to drought, flood, or salinity using inter-simple sequence repeat (ISSR) markers. Based on all markers, the nine tolerant varieties formed one cluster distinct from the cluster of three control varieties. The salt-tolerant varieties were closest to two flood-tolerant varieties, and together they were distinct from the drought-tolerant varieties. (GA)(8)YG was the most informative primer, showing the highest polymorphic information content (PIC) and resolving power (Rp). The drought-, flood-, and salt-tolerant varieties grouped in three distinct clusters within the group of tolerant varieties, when (GA)(8)YG was used. Sabita was the only exception. The two aus varieties, Nagina22 and FR13A, were separated and grouped with the drought- and flood-tolerant varieties, respectively, but they were together in dendrograms based on other primers. The results show that ISSR markers associated with (GA)(8)YG delineated the three groups of stress-tolerant varieties from each other and can be used to identify genes/new alleles associated with the three abiotic stresses in rice germplasm.

  3. Simple and Rapid Molecular Techniques for Identification of Amylose Levels in Rice Varieties

    Science.gov (United States)

    Cheng, Acga; Ismail, Ismanizan; Osman, Mohamad; Hashim, Habibuddin

    2012-01-01

    The polymorphisms of Waxy (Wx) microsatellite and G-T single-nucleotide polymorphism (SNP) in the Wx gene region were analyzed using simplified techniques in fifteen rice varieties. A rapid and reliable electrophoresis method, MetaPhor agarose gel electrophoresis (MAGE), was effectively employed as an alternative to polyacrylamide gel electrophoresis (PAGE) for separating Wx microsatellite alleles. The amplified products containing the Wx microsatellite ranged from 100 to 130 bp in length. Five Wx microsatellite alleles, namely (CT)10, (CT)11, (CT)16, (CT)17, and (CT)18 were identified. Of these, (CT)11 and (CT)17 were the predominant classes among the tested varieties. All varieties with an apparent amylose content higher than 24% were associated with the shorter repeat alleles; (CT)10 and (CT)11, while varieties with 24% or less amylose were associated with the longer repeat alleles. All varieties with intermediate and high amylose content had the sequence AGGTATA at the 5′-leader intron splice site, while varieties with low amylose content had the sequence AGTTATA. The G-T polymorphism was further verified by the PCR-AccI cleaved amplified polymorphic sequence (CAPS) method, in which only genotypes containing the AGGTATA sequence were cleaved by AccI. Hence, varieties with desirable amylose levels can be developed rapidly using the Wx microsatellite and G-T SNP, along with MAGE. PMID:22754356

  4. 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.

    Science.gov (United States)

    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

  5. Genetic, physiological, and gene expression analyses reveal that multiple QTL enhance yield of rice mega-variety IR64 under drought.

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    B P Mallikarjuna Swamy

    Full Text Available BACKGROUND: Rice (Oryza sativa L. is a highly drought sensitive crop, and most semi dwarf rice varieties suffer severe yield losses from reproductive stage drought stress. The genetic complexity of drought tolerance has deterred the identification of agronomically relevant quantitative trait loci (QTL that can be deployed to improve rice yield under drought in rice. Convergent evidence from physiological characterization, genetic mapping, and multi-location field evaluation was used to address this challenge. METHODOLOGY/PRINCIPAL FINDINGS: Two pairs of backcross inbred lines (BILs from a cross between drought-tolerant donor Aday Sel and high-yielding but drought-susceptible rice variety IR64 were produced. From six BC4F3 mapping populations produced by crossing the +QTL BILs with the -QTL BILs and IR64, four major-effect QTL--one each on chromosomes 2, 4, 9, and 10--were identified. Meta-analysis of transcriptome data from the +QTL/-QTL BILs identified differentially expressed genes (DEGs significantly associated with QTL on chromosomes 2, 4, 9, and 10. Physiological characterization of BILs showed increased water uptake ability under drought. The enrichment of DEGs associated with root traits points to differential regulation of root development and function as contributing to drought tolerance in these BILs. BC4F3-derived lines with the QTL conferred yield advantages of 528 to 1875 kg ha⁻¹ over IR64 under reproductive-stage drought stress in the targeted ecosystems of South Asia. CONCLUSIONS/SIGNIFICANCE: Given the importance of rice in daily food consumption and the popularity of IR64, the BC4F3 lines with multiple QTL could provide higher livelihood security to farmers in drought-prone environments. Candidate genes were shortlisted for further characterization to confirm their role in drought tolerance. Differential yield advantages of different combinations of the four QTL reported here indicate that future research should include

  6. The Efforts for Productivity and Income Improvement of Rice Farming Through the Use New Superior Variety (Case Study

    Directory of Open Access Journals (Sweden)

    Nyoman Ngurah Arya

    2017-07-01

    Full Text Available Various efforts to increase rice production have been done in order to achieve rice self-sufficiency and food security, one of which is the creation of some New Superior Varieties (NSVs of paddy. This study aimed to analyze the productivity, income, and efficiency of rice farming of New Superior Varieties, including Inpari 29, Inpari 31, and Inpari 32. This research was conducted on December 2014 until April 2015 in Subak Gubug I, Gubug village, as one of the centers of rice production in Tabanan Regency. The study involved 30 farmers who planted those three new superior varieties in 9.38 hectares of wet land area.  Each farmer used as replicates. Data were collected using interview and direct observation. Data was analyzed by Analysis of Variance (ANOVA. The results showed that Inpari 31 variety have the highest productivity, the highest revenue, the most efficient, and significantly different from the Inpari 29 and 32. Multiplication and dissemination of Inpari 31 variety to farmers can be done as soon as possible to increase rice production, achieve rice self-sufficiency and food security.

  7. Genome-Wide Association Studies Reveal New Genetic Targets for Five Panicle Traits of International Rice Varieties

    Directory of Open Access Journals (Sweden)

    ZHANG Ya-fang

    2015-09-01

    Full Text Available Narrow genetic background is a key limiting factor in breeding stable high-yielding rice. The introduction and utilization of international rice core germplasm is an important way to increase the genetic diversity of domestic rice varieties. We conducted a genome-wide association study on 5 panicle traits of 315 rice accessions introduced from the international rice micro-core germplasm bank. Based on the tests from Yangzhou of China and Arkansas of American, environment exhibited a significant impacts on panicle length and primary branch number, while grain length, grain width and grain length/width ratio were insensitive to environment changes. We discovered a total of 7, 5, 10, 8 and 6 chromosomal regions or single nucleotide polymorphism marker loci that were significantly associated with primary branch number, panicle length, grain length, grain width and grain length/width ratio, respectively. Among them, eleven regions were associated with grain shape and one region associated with primary branch number, showing the good consistence in two different environments. Significant linear correlation was discovered between the average trait value and the number of favorable alleles carried by the varieties in all associated loci. Among the associated loci, varieties in aromatic and tropical japonica sub-groups possessed most favorable alleles, while those in temperate japonica sub-group contained the least. The domestic varieties mainly harbored unfavorable alleles in six of the associated loci being detected. On the contrary, 15 varieties from 11 different countries harbored more favorable alleles (as many as 30 or more than the others. Remarkably, all these 15 varieties belonged to the tropical japonica sub-group. In conclusion, our study demonstrates that varieties in the tropical japonica sub-group had high potentials for breeding stable high-yielding rice. Based on this discovery, we proposed a new approach for improving the panicle traits

  8. Effect of Cold-Water Irrigation on Grain Quality Traits in japonica Rice Varieties from Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    Guo-zhen ZHAO

    2009-09-01

    Full Text Available The response of grain quality traits to cold-water irrigation and its correlation with cold tolerance were studied in 11 japonica rice varieties from Yunnan Province, China. The results indicated that the response of grain quality traits to the cold-water stress varied with rice varieties and grain quality traits. Under the cold-water stress, grain width, chalky rice rate, whiteness, 1000-grain weight, brown rice rate, taste meter value, peak viscosity, trough viscosity, breakdown viscosity and final viscosity significantly decreased, whereas grain length-width ratio, head rice rate, alkali digestion value, protein content and setback viscosity markedly increased. However, the other traits such as grain length, amylose content, milled rice rate, peak viscosity time and pasting temperature were not significantly affected by the cold-water stress. Significant correlations were discovered between phenotypic acceptability and cold response indices of taste meter value, protein content, peak viscosity and breakdown viscosity. Therefore, it would be very important to improve the cold tolerance of Yunnan rice varieties in order to stabilize and improve their eating quality.

  9. A comparative study on starch digestibility, glycemic index and resistant starch of pigmented ('Njavara' and 'Jyothi') and a non-pigmented ('IR 64') rice varieties.

    Science.gov (United States)

    Deepa, G; Singh, Vasudeva; Naidu, K Akhilender

    2010-12-01

    In vitro starch digestibility and glycemic indices of three rice varieties- 'Njavara', 'Jyothi' (pigmented rice verities) and 'IR 64' (non-pigmented rice) with similar amylose content were studied. Starch digestibility studies showed differences in glycemic response in three types of rice. The rate of starch hydrolysis was maximum (67.3%) in 'Njavara' rice compared to other two rice varieties. 'Njavara' exhibited the lowest kinetic constant (k) indicating inherent resistance to enzymatic hydrolysis. The glycemic load (GL) and glycemic index (GI) of 'Njavara' were similar to 'Jyothi' and 'IR 64'. Resistant starch content was high in pigmented rice varieties compared to 'IR 64'. The resistant starch content of dehusked and cooked rice increased with the storage time at refrigeration temperature (4°C). 'Njavara' is an easily digestible rice and can be used for baby and geriatric foods.

  10. Stress Tolerance Profiling of a Collection of Extant Salt-Tolerant Rice Varieties and Transgenic Plants Overexpressing Abiotic Stress Tolerance Genes

    National Research Council Canada - National Science Library

    Kurotani, Ken-ichi; Yamanaka, Kazumasa; Toda, Yosuke; Ogawa, Daisuke; Tanaka, Maiko; Kozawa, Hirotsugu; Nakamura, Hidemitsu; Hakata, Makoto; Ichikawa, Hiroaki; Hattori, Tsukaho; Takeda, Shin

    2015-01-01

    .... In this study, we investigated the profiles of stress tolerance of nine salt-tolerant rice varieties and transgenic rice lines carrying constitutively expressed genes that are potentially involved...

  11. Analysis of SSH library of rice variety Aganni reveals candidate gall midge resistance genes.

    Science.gov (United States)

    Divya, Dhanasekar; Singh, Y Tunginba; Nair, Suresh; Bentur, J S

    2016-03-01

    The Asian rice gall midge, Orseolia oryzae, is a serious insect pest causing extensive yield loss. Interaction between the gall midge and rice genotypes is known to be on a gene-for-gene basis. Here, we report molecular basis of HR- (hypersensitive reaction-negative) type of resistance in Aganni (an indica rice variety possessing gall midge resistance gene Gm8) through the construction and analysis of a suppressive subtraction hybridization (SSH) cDNA library. In all, 2,800 positive clones were sequenced and analyzed. The high-quality ESTs were assembled into 448 non-redundant gene sequences. Homology search with the NCBI databases, using BlastX and BlastN, revealed that 73% of the clones showed homology to genes with known function and majority of ESTs belonged to the gene ontology category 'biological process'. Validation of 27 putative candidate gall midge resistance genes through real-time PCR, following gall midge infestation, in contrasting parents and their derived pre-NILs (near isogenic lines) revealed induction of specific genes related to defense and metabolism. Interestingly, four genes, belonging to families of leucine-rich repeat (LRR), heat shock protein (HSP), pathogenesis related protein (PR), and NAC domain-containing protein, implicated in conferring HR+ type of resistance, were found to be up-regulated in Aganni. Two of the reactive oxygen intermediates (ROI)-scavenging-enzyme-coding genes Cytosolic Ascorbate Peroxidase1, 2 (OsAPx1 and OsAPx2) were found up-regulated in Aganni in incompatible interaction possibly suppressing HR. We suggest that Aganni has a deviant form of inducible, salicylic acid (SA)-mediated resistance but without HR.

  12. TALEN-mediated targeted mutagenesis produces a large variety of heritable mutations in rice.

    Science.gov (United States)

    Zhang, Hui; Gou, Feng; Zhang, Jinshan; Liu, Wenshan; Li, Qianqian; Mao, Yanfei; Botella, José Ramón; Zhu, Jian-Kang

    2016-01-01

    CRISPR/Cas9 and TALEN are currently the two systems of choice for genome editing. We have studied the efficiency of the TALEN system in rice as well as the nature and inheritability of TALEN-induced mutations and found important features of this technology. The N287C230 TALEN backbone resulted in low mutation rates (0-6.6%), but truncations in its C-terminal domain dramatically increased efficiency to 25%. In most transgenic T0 plants, TALEN produced a single prevalent mutation accompanied by a variety of low-frequency mutations. For each independent T0 plant, the prevalent mutation was present in most tissues within a single tiller as well as in all tillers examined, suggesting that TALEN-induced mutations occurred very early in the development of the shoot apical meristem. Multigenerational analysis showed that TALEN-induced mutations were stably transmitted to the T1 and T2 populations in a normal Mendelian fashion. In our study, the vast majority of TALEN-induced mutations (~81%) affected multiple bases and ~70% of them were deletions. Our results contrast with published reports for the CRISPR/Cas9 system in rice, in which the predominant mutations affected single bases and deletions accounted for only 3.3% of the overall mutations. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  13. Agronomic evaluation of four improved rice varieties in different sowing periods

    Directory of Open Access Journals (Sweden)

    Genry Hernández Carrillo

    2017-04-01

    Full Text Available A study to evaluate the agronomic performance of four rice varieties in different seasons, on flooded soil, using direct plantation, was developed at the Local Station for Grain Research, in the municipality of Vertientes, province of Camaguey, Cuba. A block random design was used in the study, with five replicas, through a bifactorial experiment with four treatments (Prosequisa 4, IA Cuba 31, IACuba 40, and Jucarito 104, as control, the sowing period included January, February, March, April, May, June, July, and August. The parameters evaluated were, cycle (days from germination to harvest, final plant height, fertile panicles per m2, filled grain per panicle, 1000-grain mass (14% humidity, crop yields and industrial quality. The highest yields were accomplished in February and June (pattern variety and Prosequisa 4, with 8.2 t/ha-1, in each month. Concerning industrial yields, the best results were achieved in IACuba 31 (66.4; 66.1; and 63.3% full white grain in February, June and July. The most profitable varieties were Prosequisa 4, Jucarito 104, and IACuba 31, in the different seasons evaluated.

  14. Genome-wide association study of cold tolerance of Chinese indica rice varieties at the bud burst stage.

    Science.gov (United States)

    Zhang, Mengchen; Ye, Jing; Xu, Qun; Feng, Yue; Yuan, Xiaoping; Yu, Hanyong; Wang, Yiping; Wei, Xinghua; Yang, Yaolong

    2018-01-10

    A region containing three genes on chromosome 1 of indica rice was associated with cold tolerance at the bud burst stage; these results may be useful for breeding cold-tolerant lines. Low temperature at the bud burst stage is one of the major abiotic stresses limiting rice growth, especially in regions where rice seeds are sown directly. In this study, we investigated cold tolerance of rice at the bud burst stage and conducted a genome-wide association study (GWAS) based on the 5K rice array of 249 indica rice varieties widely distributed in China. We improved the method to assess cold tolerance at the bud burst stage in indica rice, and used severity of damage (SD) and seed survival rate (SR) as the cold-tolerant indices. Population structure analysis demonstrated that the Chinese indica panel was divided into three subgroups. In total, 47 significant single-nucleotide polymorphism (SNP) loci associated with SD and SR, were detected by association mapping based on mixed linear model. Because some loci overlapped between SD and SR, the loci contained 13 genome intervals and most of them have been reported previously. A major QTL for cold tolerance on chromosome 1 at the position of 31.6 Mb, explaining 13.2% of phenotypic variation, was selected for further analysis. Through LD decay, GO enrichment, RNA-seq data, and gene expression pattern analyses, we identified three genes (LOC_Os01g55510, LOC_Os01g55350 and LOC_Os01g55560) that were differentially expressed between cold-tolerant and cold-sensitive varieties, suggesting they may be candidate genes for cold tolerance. Together, our results provide a new method to assess cold tolerance in indica rice, and establish the foundation for isolating genes related to cold tolerance that could be used in rice breeding.

  15. TECHNICAL ECONOMIC FEASIBILITY OF PADDY RICE FIELDS VARIETY OF APPROACH PTT SPECIFIC LOCATIONS IN PAPUA (Case Jayapura

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    Afrizal Malik

    2013-01-01

    Full Text Available Study aims to determine technical economically feasibility of irrigration rice in village of Sumbe, Namblong District, Jayapura on-farm research involving farmers with an area of 2.50 ha cooperators, July to November 2011. Technology introduced: PTT, 4:1 legowo systems, seed varieties Inpari labeled 1, 2, 4, 6, 7, 9, 10, and Sintanur. Fertilizer: urea 150 kg +100 kg +100 kg SP-36 Phonska KCl +50 kg per ha. Variables: height and number of tillers 35 and 65 dap, weight of 1000 seeds, productivity, input, and output. Data were analyzed descriptively. Highest productivity in varieties Inpari 7 (7.925 tonnes per ha Milled Rice (MR and lowest Sintanur varieties (4.625 tonnes per ha MR. Pest stand: rice leaffolder and stinky rice pest. Lowest expenditure on non-cooperators Ciherang farmers IDR 12.15 million per ha per Growing Season (GS and highest in varieties Inpari 7 (IDR 15,005,000 per ha per GS. Lowest Acceptance Ciherang farmers on non-cooperators, IDR 16.4 million per ha per GS and highest in varieties Inpari 7, IDR 27.7 million per ha per GS. If farmers apply recommendation technologies using Inpari 7 varieties, farmers receiving IDR 3,173,750 per month (greater than Regional Minimum Wage of Jayapura. Need government support in order to minimize dependence on outside

  16. Value added products with popular low grade rice varieties of Andhra Pradesh

    National Research Council Canada - National Science Library

    Anitha, G; Rajyalakshmi, P

    2014-01-01

    ...); rice semolina (instant kheer mix and instant upma mix), and flaked rice (nutritious bar). The products were evaluated for nutritional, cooking quality characteristics, consumer acceptability and shelf-life...

  17. Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper.

    Science.gov (United States)

    Dong, Yan; Fang, Xianping; Yang, Yong; Xue, Gang-Ping; Chen, Xian; Zhang, Weilin; Wang, Xuming; Yu, Chulang; Zhou, Jie; Mei, Qiong; Fang, Wang; Yan, Chengqi; Chen, Jianping

    2017-01-01

    The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH) is one of the major destructive pests of rice (Oryza sativa L.). Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant) and 02428 (SBPH-susceptible), were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05) at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs) showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD) and glutathione (GSH) were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT) activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA)-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and physiological

  18. Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper

    Directory of Open Access Journals (Sweden)

    Yan Dong

    2017-10-01

    Full Text Available The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH is one of the major destructive pests of rice (Oryza sativa L.. Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant and 02428 (SBPH-susceptible, were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05 at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD and glutathione (GSH were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and

  19. Use of the p-SINE1-r2 in inferring evolutionary relationships of Thai rice varieties with AA genome

    Directory of Open Access Journals (Sweden)

    Preecha Prathepha

    2006-01-01

    Full Text Available In a previous study we described the prevalence and distribution in Thailand of the retroposon p- SINE1-r2, in the intron 10 of the waxy gene in cultivated and wild rice with the AA genome. In this study, additional varieties of rice were collected and sequencing was used to further characterize p-SINE1-r2. It was found that the length of the p-SINE1-r2 nucleotide sequences was about 125 bp, flanked by identical direct repeats of a 14 bp sequence. These sequences were compared and found to be similar to the sequences of p- SINE1-r2 found in Nipponbare, a rice strain discussed in a separate study. However, when compared the 48 DNA sequences identified in this study, much dissimilarity was found within the nucleotide sequences of p- SINE1-r2, in the form of base substitution mutations. Phylogenetic relationships inferred from the nucleotide sequences of these elements in cultivated rice (O. sativa and wild rice (O. nivara. It was found that rice accessions collected from the same geographical distribution have been placed in the same clade. The phylogenetic tree supports the origin and distribution of these rice strains.

  20. Effect of fluoride on photosynthesis, growth and accumulation of four widely cultivated rice (Oryza sativa L.) varieties in India.

    Science.gov (United States)

    Mondal, Naba Kumar

    2017-10-01

    Long-term use of fluoride contaminated groundwater to irrigate crops; especially paddy rice (Oryza sativa L.) has resulted in elevated soil fluoride levels in Eastern India. There is, therefore, growing concern regarding accumulation of fluoride in rice grown on these soils. A laboratory experiment was conducted to investigate the effect of F on germination and phytotoxicity of four varieties of rice (Orzya sativa L.) (MTU-1010; IET-4094; IET-4786 and GB-1) grown in petri dish in a green house with inorganic sodium fluoride (NaF). Three different levels (0, 5, 10 and 20mg/L) of NaF solution were applied. At the end of the experiment (28 days), biochemical analysis (pigment, sugar, protein, amino acid and phenol), lipid peroxidation, root ion leakage and catalase activity along with fluoride accumulation and fresh and dry weight of roots and shoots of four cultivars were measured. The results revealed that all the four studied varieties exhibited gradual decrease of germination pattern with increasing concentration of F. Pigment and growth morphological study clearly demonstrated that the variety IET-4094 was the least influenced by F compare to the other three varieties of rice. The translocation factor (TF) was recorded to be the highest for variety IET-4786 (0.215 ± 0.03) at 5mg/L F concentration. All the four varieties showed higher level of fluoride accumulation in root than in shoot. Variable results were recorded for biochemical parameters and lipid peroxidation. Catalase activity and relative conductivity (root ion leakage) gradually increased with increasing F concentration for all the four varieties. It is speculated that fluoride accumulation in rice straw at very high levels will affect the feeding cattle and such contaminated straw could be a direct threat to their health and also, indirectly, to human health via presumably contaminated meat and milk. Copyright © 2017. Published by Elsevier Inc.

  1. Differential gene expression in gall midge susceptible rice genotypes revealed by suppressive subtraction hybridization (SSH) cDNA libraries and microarray analysis.

    Science.gov (United States)

    Rawat, Nidhi; Neeraja, Chiruvuri Naga; Nair, Suresh; Bentur, Jagadish S

    2012-12-01

    A major pest of rice, the Asian rice gall midge (Orseolia oryzae Wood-Mason), causes significant yield losses in the rice growing regions throughout Asia. Feeding by the larvae induces susceptible plants to produce nutritive tissue to support growth and development. In order to identify molecular signatures during compatible interactions, genome wide transcriptional profiling was performed using SSH library and microarray technology. Results revealed up-regulation of genes related to primary metabolism, nutrient relocation, cell organization and DNA synthesis. Concomitantly, defense, secondary metabolism and signaling genes were suppressed. Further, real-time PCR validation of a selected set of 20 genes, in three susceptible rice varieties (TN1, Kavya and Suraksha) during the interaction with the respective virulent gall midge biotypes, also revealed variation in gene expression in Kavya as compared to TN1 and Suraksha. These studies showed that virulent insects induced the plants to step up metabolism and transport nutrients to their feeding site and suppressed defense responses. But Kavya rice mounted an elevated defense response during early hours of virulent gall midge infestation, which was over-powered later, resulting in host plant susceptibility.

  2. Dissection of broad-spectrum resistance of the Thai rice variety Jao Hom Nin conferred by two resistance genes against rice blast.

    Science.gov (United States)

    Chaipanya, Chaivarakun; Telebanco-Yanoria, Mary Jeanie; Quime, Berlaine; Longya, Apinya; Korinsak, Siripar; Korinsak, Siriporn; Toojinda, Theerayut; Vanavichit, Apichart; Jantasuriyarat, Chatchawan; Zhou, Bo

    2017-12-01

    Rice (Oryza sativa) is one of the most important food crops in the world. Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most destructive rice diseases worldwide. To effectively cope with this problem, the use of rice blast resistance varieties through innovative breeding programs is the best strategy to date. The Thai rice variety Jao Hom Nin (JHN) showed broad-spectrum resistance against Thai rice blast isolates. Two QTLs for blast resistance in JHN were reported on chromosome 1 (QTL1) and 11 (QTL11). Monogenic lines of QTL1 (QTL1-C) and QTL11 (QTL11-C) in the CO39 genetic background were generated. Cluster analysis based on the disease reaction pattern of QTL1-C and QTL11-C, together with IRBLs, showed that those two monogenic lines were clustered with IRBLsh-S (Pish) and IRBL7-M (Pi7), respectively. Moreover, sequence analysis revealed that Pish and Pi7 were embedded within the QTL1 and QTL11 delimited genomic intervals, respectively. This study thus concluded that QTL1 and QTL11 could encode alleles of Pish and Pi7, designated as Pish-J and Pi7-J, respectively. To validate this hypothesis, the genomic regions of Pish-J and Pi7-J were cloned and sequenced. Protein sequence comparison revealed that Pish-J and Pi7-J were identical to Pish and Pi7, respectively. The holistic disease spectrum of JHN was found to be exactly attributed to the additive ones of both QTL1-C and QTL11-C. JHN showed broad spectrum resistance against Thai and Philippine rice blast isolates. As this study demonstrated, the combination of two resistance genes, Pish-J and Pi7-J, in JHN, with each controlling broad-spectrum resistance to rice blast disease, explains the high level of resistance. Thus, the combination of Pish and Pi7 can provide a practical scheme for breeding durable resistance in rice against rice blast disease.

  3. Jasmonic acid-mediated defense suppresses brassinosteroid-mediated susceptibility to Rice black streaked dwarf virus infection in rice.

    Science.gov (United States)

    He, Yuqing; Zhang, Hehong; Sun, Zongtao; Li, Junmin; Hong, Gaojie; Zhu, Qisong; Zhou, Xuebiao; MacFarlane, Stuart; Yan, Fei; Chen, Jianping

    2017-04-01

    Plant hormones play a vital role in plant immune responses. However, in contrast to the relative wealth of information on hormone-mediated immunity in dicot plants, little information is available on monocot-virus defense systems. We used a high-throughput-sequencing approach to compare the global gene expression of Rice black-streaked dwarf virus (RBSDV)-infected rice plants with that of healthy plants. Exogenous hormone applications and transgenic rice were used to test RBSDV infectivity and pathogenicity. Our results revealed that the jasmonic acid (JA) pathway was induced while the brassinosteroid (BR) pathway was suppressed in infected plants. Foliar application of methyl jasmonate (MeJA) or brassinazole (BRZ) resulted in a significant reduction in RBSDV incidence, while epibrassinolide (BL) treatment increased RBSDV infection. Infection studies using coi1-13 and Go mutants demonstrated JA-mediated resistance and BR-mediated susceptibility to RBSDV infection. A mixture of MeJA and BL treatment resulted in a significant reduction in RBSDV infection compared with a single BL treatment. MeJA application efficiently suppressed the expression of BR pathway genes, and this inhibition depended on the JA coreceptor OsCOI1. Collectively, our results reveal that JA-mediated defense can suppress the BR-mediated susceptibility to RBSDV infection. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  4. Spectral reflectance of rice canopies and red edge position (REP) as indicator of high yield varieties

    NARCIS (Netherlands)

    Abbasi, M.; Darvishsefat, A.; Schaepman, M.E.

    2010-01-01

    Rice is the staple food in Iran. More than 80 percent of rice area is distributed in the two northern provinces of Mazandaran and Gilan, so that investment in increasing the quantity and quality can impact an effective role in economic independence and sustainable agriculture. Increased efficiency

  5. Impact of water management on root morphology, growth and yield component of lowland rice varieties under the organic system of rice intensification

    Directory of Open Access Journals (Sweden)

    A F Aziez

    2018-01-01

    Full Text Available Water management is one of the keys to success in increasing rice production in paddy fields. Paddy rice production will decrease if the rice plants suffer from water stress, and conversely conventional cultivation is very wasteful of water. Local aromatic varieties have deeper rooting character than improved varieties making it more efficient in using water. The purpose of this study was to obtain more efficient and more productive aromatic local varieties in the use of irrigation water in the SRI organic cultivation system. This research was conducted in organic rice fields in Kebonagung village, Imogiri, Bantul with split plot design of 2 factors with 4 replications. Factor I: The mode of irrigation consists of (a intermittent irrigation, and (b continuous irrigation and Factor II: varieties consisting of (a Mentikwangi, (b Gabusan, (c Sintanur and (d IR64. The observation parameters included (1 root characters i.e. surface area of root, total length of root, and dry weight of root, (2 plant growth analysis i.e. specific leaf weight, net assimilation rate, plant growth rate, (3 and yield components i.e. weight 1000 grains, grain weight per hill, and grain weight per plot. The results showed that intermittent irrigation increased the surface area of root and the dry weight of root of Mentikwangi variety, and increased the specific leaf weight and weight of 1000 grains of IR64 variety, and increased the specific leaf weight and the net assimilation rate of Sintanur variety. Grain weight per hill and per plot showed no difference between intermittent irrigation and continuous irrigation. Grain weight per hill and per plot in intermittent irrigation achieved by Gabusan variety were 35.69 g and 14.28 kg respectively, while in continuous irrigation the grain weight achieved by Gabusan variety were 37.69 g and 15.08 kg respectively. In conclusion, there was no difference in yield between intermittent irrigation and continuous irrigation, so that the

  6. Assessment of Relationship Between Bacterial Stripe Resistance And Leaf Protein Bands In Rice (Oryza sativa L.) Varieties.

    Science.gov (United States)

    Talei, D.; Fotokian, M. H.

    2008-01-01

    Bacterial stripe as a new rice disease in Iran is more frequent nowadays. The objective of this study was to assessment of resistance in rice varieties together with evaluating of zymogram bands resulted from SDS PAGE electrophoresis of leaf proteins. For this purpose, 30 lines were tested in a randomized complete block design with three replications. The analysis of variance showed that there was significant difference between genotypes for resistance. Mean compare based on field results revealed that Domsiyah had the lowest resistance while Nemat and 7162 demonstrated the highest resistance. Laboratory results showed that there were significant difference between protein bands resulted from sensitive and resistance verities. Twenty bands were observed through SDS PAGE electrophoresis of leaf proteins. The 9th and 12th bands were found in sensitive varieties while were not in resistance genotypes. According to the results of this study, 7162 variety can be considered as the sources of resistance in breeding programs. Meanwhile attending to existence of 9th and 12th bands in sensitive varieties, resistance against bacterial stripe of rice maybe influenced by absence of these proteins.

  7. Genome wide association analysis of cold tolerance at germination in temperate japonica rice (Oryza sativa L.) varieties.

    Science.gov (United States)

    Sales, Ester; Viruel, Juan; Domingo, Concha; Marqués, Luis

    2017-01-01

    A pool of 200 traditional, landraces and modern elite and old cultivars of rice, mainly japonica varieties adapted to temperate regions, have been used to perform a genome wide association study to detect chromosome regions associated to low temperature germination (LTG) regulation using a panel of 1672 SNP markers. Phenotyping was performed by determining growth rates when seeds were germinated at 25° and 15°C in order to separate the germination vigorousness from cold tolerance effects. As expected, the ability to produce viable seedlings varied widely among rice cultivars and also depended greatly on temperature. Furthermore, we observed a differential response during seed germination and in coleoptile elongation. Faster development at 15°C was observed in seeds from varieties traditionally used as cold tolerant parents by breeders, along with other potentially useful cultivars, mainly of Italian origin. When phenotypic data were combined with the panel of SNPs for japonica rice cultivars, significant associations were detected for 31 markers: 7 were related to growth rate at 25°C and 24 to growth rates at 15°. Among the latter, some chromosome regions were associated to LTG while others were related to coleoptile elongation. Individual effects of the associated markers were low, but by combining favourable alleles in a linear regression model we estimated that 27 loci significantly explained the observed phenotypic variation. From these, a core panel of 13 markers was selected and, furthermore, two wide regions of chromosomes 3 and 6 were consistently associated to rice LTG. Varieties with higher numbers of favourable alleles for the panels of associated markers significantly correlated with increased phenotypic values at both temperatures, thus corroborating the utility of the tagged markers for marker assisted selection (MAS) when breeding japonica rice for LTG.

  8. Evaluating Non-Aromatic Rice Varieties for Growth and Yield under Different Rates of Soil Applied Boron

    Directory of Open Access Journals (Sweden)

    Javaid Ahmed Shah

    2016-05-01

    Full Text Available Balanced boron (B fertilization has prime importance to obtain maximum paddy yield. The range between B deficiency and toxicity is smaller than most plant nutrients, though B requirement among different crops varies widely. The adequate dose of B for one genotype can either be insufficient or toxic to other. Hence, without knowing the actual requirements of crop varieties, B application can be risky due to the toxicity hazards. A field experiment was undertaken at experimental farm of Nuclear Institute of Agriculture (NIA Tandojam during 2013, to evaluate the B requirement of two non-aromatic rice varieties. The experiment was arranged in split plot design with three repeats. Two rice varieties Sarshar and Shandar were grown in main plots with four rates of B: 0.5, 1.0, 1.5 and 2.0 kg ha-1 and control (0 kg ha-1 in sub plots. Both the varieties responded differently to B rates. Sarshar produced the highest paddy yield (5691 kg ha-1 at a rate of 1.5 kg B ha-1 and was 18% greater than control, Shandar produced the highest yield (6075 kg ha-1 at a rate of 1.0 kg B ha-1and was 5% greater than control. B accumulation in paddy and straw of both varieties increased with the increasing B rates. Both varieties were also significantly (p<0.05 varied in B accumulations. Comparatively, rice variety Sarshar accumulated 9% and 22% more B in straw and paddy than the Shandar. Thus, the B requirement of Sarshar was relatively higher than the Shandar. Shandar can be grown without the additional B application, whereas, Sarshar requires additional B for its maximum harvest in B deficient soils.

  9. Effects of Chalkiness on Cooking, Eating and Nutritional Qualities of Rice in Two indica Varieties

    National Research Council Canada - National Science Library

    LIU Qi-hua ZHOU Xue-biao YANG Lian-qun LI Tian

    2009-01-01

    ... (conventional indica rice) as materials. Compared with the milled rice without chalkiness, amylose content, final viscosity, setback and consistence increased significantly, while gel consistence, peak viscosity and breakdown decreased...

  10. Evaluating Crossbred Red Rice Variants for Postprandial Glucometabolic Responses: A Comparison with Commercial Varieties

    Directory of Open Access Journals (Sweden)

    Chee-Hee Se

    2016-05-01

    Full Text Available Consumption of white rice predisposes some Asian populations to increased risk of type 2 diabetes. We compared the postprandial glucometabolic responses to three newly-developed crossbred red rice variants (UKMRC9, UKMRC10, UKMRC11 against three selected commercial rice types (Thai red, Basmati white, Jasmine white using 50-g carbohydrate equivalents provided to 12 normoglycaemic adults in a crossover design. Venous blood was drawn fasted and postprandially for three hours. Glycaemic (GI and insulin (II indices, incremental areas-under-the-curves for glucose and insulin (IAUCins, indices of insulin sensitivity and secretion, lactate and peptide hormones (motilin, neuropeptide-Y, orexin-A were analyzed. The lowest to highest trends for GI and II were similar i.e., UKMRC9 < Basmati < Thai red < UKMRC10 < UKMRC11 < Jasmine. Postprandial insulinaemia and IAUCins of only UKMRC9 were significantly the lowest compared to Jasmine. Crude protein and fiber content correlated negatively with the GI values of the test rice. Although peptide hormones were not associated with GI and II characteristics of test rice, early and late phases of prandial neuropeptide-Y changes were negatively correlated with postprandial insulinaemia. This study indicated that only UKMRC9 among the new rice crossbreeds could serve as an alternative cereal option to improve diet quality of Asians with its lowest glycaemic and insulinaemic burden.

  11. Effect of Intermittent Drying Conditions on Fissuring Percentage and Process Duration of Long and Medium Rough Rice Varieties

    Directory of Open Access Journals (Sweden)

    A. Ghasemi

    2016-02-01

    Full Text Available One of the factors which affect the quality of rice during milling is internal fissures created during and after drying operation. In many industrial countries intermittent drying method is hired to reduce the moisture content of rough rice in order to reduce the drying time and maintain the quality of the final product. A high percentage of rice breakage during milling process, at least in Iran, necessitates performing the intermittent drying process and optimize it for Iranian varieties. In this study, the effect of this method (drying-tempering and continuous drying method (no tempering on fissuring percentage of Hashemi (long grain and Koohsar (medium grain varieties was investigated. The experiments were carried out at constant drying and tempering temperature of 60 °C, drying durations of 20, 40 and 60 min, and tempering durations of 0 (continuous drying, 40, 80, 120, 160, 200, 240 min. The results revealed that the tempering process significantly reduced the drying time and fissured kernels percentage. Moreover, for both varieties it was observed that the rice fissuring decreased significantly by continuing the tempering process until certain durations. Overall, for optimization of intermittent drying process in terms of the considered qualitative parameters, i.e. reducing energy consumption and losses, conducting 160 and 200 min tempering process after 40 min drying was found appropriate for Hashemi and Koohsar varieties, respectively. In addition, according to the higher fissuring for Koohsar (medium grain compared to Hashemi (long grain, it can be concluded that physical properties such as kernel slenderness ratio is effective on its fissuring.

  12. Susceptibility of the rice stem borer, Chilo suppressalis (Lepidoptera: Crambidae), to flubendiamide in China.

    Science.gov (United States)

    Wu, Min; Zhang, Shuai; Yao, Rong; Wu, Shunfan; Su, Jianya; Gao, Congfen

    2014-06-01

    The rice stem borer, Chilo suppressalis (Walker), is an important rice pest in China, and has evolved resistance to several classes of insecticides. Flubendiamide is a phthalic diamide insecticide that shows selective insecticidal activity against lepidopterous insects. The susceptibility of 40 field populations of C. suppressalis, collected in 2011 and 2012 in seven provinces of south-eastern China, to flubendiamide was determined through rice seedling dipping bioassay method. Of these 40 populations, seven populations that were seldom exposed to flubendiamide were used to set up the baseline sensitivity, and the LC50 value was 0.092 mg/L. Variation in susceptibility among the 40 field populations was high (34-fold). The range of mean lethal concentration (LC50) values in response to this chemical was between 0.032 mg/L (FS11) and 1.090 mg/L (JH12) across the populations. Substantial variations of the susceptibility to flubendiamide were detected among different geographic populations. There was no significant difference observed between years for most populations, except for populations from Jinhua and Lujiang. Resistance ratios to the chemical ranged from 0.8 to 11.8, indicating that most colonies remained susceptible or showed certain decrease in susceptibility. It was found that 16 of the 40 populations had some level of resistance. However, moderate level of resistance was discovered in only one population from JH12 from Zhejiang province (11.8-fold). Other 15 populations showed low level of resistance (5.1-9.3-fold) to flubendiamide. These data are useful in future monitoring programs for detecting any changes in susceptibility as a result of using flubendiamide.

  13. Impact of phenolic compounds and related enzymes in Sorghum varieties for resistance and susceptibility to biotic and abiotic stresses

    NARCIS (Netherlands)

    Dicko, M.H.; Gruppen, H.; Barro, C.; Traore, A.S.; Berkel, van W.J.H.; Voragen, A.G.J.

    2005-01-01

    Contents of phenolic compounds and related enzymes before and after sorghum grain germination were compared between varieties either resistant or susceptible to biotic (sooty stripe, sorghum midge, leaf anthracnose, striga, and grain molds) and abiotic (lodging, drought resistance, and photoperiod

  14. Evolvement of transgenic male-sterility and fertility-restoration system in rice for production of hybrid varieties.

    Science.gov (United States)

    Rao, Gundra Sivakrishna; Deveshwar, Priyanka; Sharma, Malini; Kapoor, Sanjay; Rao, Khareedu Venkateswara

    2018-01-01

    We have developed a unique male-sterility and fertility-restoration system in rice by combining Brassica napus cysteine-protease gene (BnCysP1) with anther-specific P12 promoter of rice for facilitating production of hybrid varieties. In diverse crop plants, male-sterility has been exploited as a useful approach for production of hybrid varieties to harness the benefits of hybrid vigour. The promoter region of Os12bglu38 gene of rice has been isolated from the developing panicles and was designated as P12. The promoter was fused with gusA reporter gene and was expressed in Arabidopsis and rice systems. Transgenic plants exhibited GUS activity in tapetal cells and pollen of the developing anthers indicating anther/pollen-specific expression of the promoter. For engineering nuclear male sterility, the coding region of Brassica napus cysteine protease1 (BnCysP1) was isolated from developing seeds and fused to P12 promoter. Transgenic rice plants obtained with P12-BnCysP1 failed to produce functional pollen grains. The F1 seeds obtained from BnCysP1 male-sterile plants and untransformed controls showed 1:1 (tolerant:sensitive) ratio when germinated on the MS medium supplemented with phosphinothricin (5 mg/l), confirming that the male sterility has been successfully engineered in rice. For male fertility restoration, transgenic rice plants carrying BnCysP1Si silencing system were developed. The pollination of BnCysP1 male-sterile (female-fertile) plants with BnCysP1Si pollen resulted in normal grain filling. The F1 seeds of BnCysP1 × BnCysP1Si when germinated on the MS basal medium containing PPT (5 mg/l) and hygromycin (70 mg/l) exhibited 1:1 (tolerant:sensitive) ratio and the tolerant plants invariably showed normal grain filling. The overall results clearly suggest that the customized male-sterility & fertility-restoration system can be exploited for quality hybrid seed production in various crops.

  15. Transgenerational variations in DNA methylation induced by drought stress in two rice varieties with distinguished difference to drought resistance.

    Directory of Open Access Journals (Sweden)

    Xiaoguo Zheng

    Full Text Available Adverse environmental conditions have large impacts on plant growth and crop production. One of the crucial mechanisms that plants use in variable and stressful natural environments is gene expression modulation through epigenetic modification. In this study, two rice varieties with different drought resistance levels were cultivated under drought stress from tilling stage to seed filling stage for six successive generations. The variations in DNA methylation of the original generation (G0 and the sixth generation (G6 of these two varieties in normal condition (CK and under drought stress (DT at seedling stage were assessed by using Methylation Sensitive Amplification Polymorphism (MSAP method. The results revealed that drought stress had a cumulative effect on the DNA methylation pattern of both varieties, but these two varieties had different responses to drought stress in DNA methylation. The DNA methylation levels of II-32B (sensitive and Huhan-3 (resistant were around 39% and 32%, respectively. Genome-wide DNA methylation variations among generations or treatments accounted for around 13.1% of total MSAP loci in II-32B, but was only approximately 1.3% in Huhan-3. In II-32B, 27.6% of total differentially methylated loci (DML were directly induced by drought stress and 3.2% of total DML stably transmitted their changed DNA methylation status to the next generation. In Huhan-3, the numbers were 48.8% and 29.8%, respectively. Therefore, entrainment had greater effect on Huhan-3 than on II-32B. Sequence analysis revealed that the DML were widely distributed on all 12 rice chromosomes and that it mainly occurred on the gene's promoter and exon region. Some genes with DML respond to environmental stresses. The inheritance of epigenetic variations induced by drought stress may provide a new way to develop drought resistant rice varieties.

  16. Studies on physico-chemical and cooking characteristics of rice bean varieties grown in NE region of India.

    Science.gov (United States)

    Bepary, Rejaul Hoque; Wadikar, D D; Neog, Seuji Borah; Patki, P E

    2017-03-01

    Rice bean (Vigna umbellata) is grown in South and Southeast Asia, and the bean has gained importance due to its nutritional strength in terms of dietary fiber, quality protein and minerals. In current study, the nutritional and functional components, cooking and thermo-gravimetric properties of eleven rice bean varieties from NE India were investigated. Results revealed that the major nutrients among the varieties ranged as follows: 54.21-60.49% carbohydrates, 15.64-21.60% protein, 1.22-2.3% fat, 5.53-6.56% crude fibre, 3.34-3.8% ash; while the functional, anti-nutritional factors and mineral were present as 1189.32-1645.8 mg gallic acid equivalent (GAE)/100 g polyphenols, 205.38-432.14 mg/100 g phytic acid, 23.14-34.12 mg/100 g oxalate, 690.7-1589.5 mg/100 g saponins, 49.90-158.17 μg/100 g hydrocyanide, 111.51-168 calcium, 5.50-10.44 zinc, 3.72-8.37 iron. Principal component analysis revealed that varieties with higher calcium, iron and ash content had lower cooking time, swelling ratio, and cooked grain hardness. It is also revealed that varieties with higher weight loss at sixth stage in thermogravimetric graph had lower carbohydrate and higher protein content. Nagadal variety had higher fat, potassium, magnesium, calcium, sodium, iron, copper and chromium content and better cooking quality as compared to the other varieties. The study revealed that Nagadal variety was superior to other varieties with respect to mineral content, cooking and thermal properties and hence have better potential in the development of value added products.

  17. IACuba 39: New variety of rice, for the favored unirrigated land.

    Directory of Open Access Journals (Sweden)

    René Pérez Polanco

    2010-09-01

    experimental conditions presented an average agricultural yield of 3.04 t / ha, has a cycle of germination to harvest about 137 days, Togosodes resistant, moderately resistant to rice blast and it is characterized by its high quality of the grain, producing at the mill more than 60% of whole grains, also has strong plants resistant to flattened and with rapid initial growth.

  18. Global transcriptional profiling of a cold-tolerant rice variety under moderate cold stress reveals different cold stress response mechanisms.

    Science.gov (United States)

    Zhao, Junliang; Zhang, Shaohong; Yang, Tifeng; Zeng, Zichong; Huang, Zhanghui; Liu, Qing; Wang, Xiaofei; Leach, Jan; Leung, Hei; Liu, Bin

    2015-07-01

    Gene expression profiling under severe cold stress (4°C) has been conducted in plants including rice. However, rice seedlings are frequently exposed to milder cold stresses under natural environments. To understand the responses of rice to milder cold stress, a moderately low temperature (8°C) was used for cold treatment prior to genome-wide profiling of gene expression in a cold-tolerant japonica variety, Lijiangxintuanheigu (LTH). A total of 5557 differentially expressed genes (DEGs) were found at four time points during moderate cold stress. Both the DEGs and differentially expressed transcription factor genes were clustered into two groups based on their expression, suggesting a two-phase response to cold stress and a determinative role of transcription factors in the regulation of stress response. The induction of OsDREB2A under cold stress is reported for the first time in this study. Among the anti-oxidant enzyme genes, glutathione peroxidase (GPX) and glutathione S-transferase (GST) were upregulated, suggesting that the glutathione system may serve as the main reactive oxygen species (ROS) scavenger in LTH. Changes in expression of genes in signal transduction pathways for auxin, abscisic acid (ABA) and salicylic acid (SA) imply their involvement in cold stress responses. The induction of ABA response genes and detection of enriched cis-elements in DEGs suggest that ABA signaling pathway plays a dominant role in the cold stress response. Our results suggest that rice responses to cold stress vary with the specific temperature imposed and the rice genotype. © 2014 Scandinavian Plant Physiology Society.

  19. Susceptibility of some Lycopersicon species and varieties to cucumber mosaic virus (CMV) and tobacco mosaic virus (TMV).

    Science.gov (United States)

    Takács, A P; Horváth, J; Kazinczi, G; Gáborjányi, R

    2005-01-01

    Susceptibility of 33 Lycopersicon species and varieties to Tobacco mosaic virus (TMV) and Cucumber mosaic virus (CMV) were studied. Plants were mechanically inoculated with the C/U1 strain of TMV and U/246 strain of CMV. Virus infection was checked by symptomatology, DAS ELISA and back inoculation (biotest). All the studied Lycopersicon species and varieties were susceptible to TMV-C/U1. L. esculentum Mill. convar. infiniens Lehm. var. flammatum Lehm., L. esculentum Mill. convar. fruticosum Lehm. var. speciosum Lehm. and L. esculentum Mill. convar. infiniens Lehm. var. validum Bail. showed extreme resistance to CMV-U/246. The other 30 species and varieties were susceptible to CMV-U/246. New compatible and incompatible host-virus relations have been reported. The extreme resistant Lycopersicon varieties could be used as resistance sources in tomato breeding.

  20. A resistance locus in the American heirloom rice variety Carolina Gold Select is triggered by TAL effectors with diverse predicted targets and is effective against African strains of Xanthomonas oryzae pv. oryzicola.

    Science.gov (United States)

    Triplett, Lindsay R; Cohen, Stephen P; Heffelfinger, Christopher; Schmidt, Clarice L; Huerta, Alejandra I; Tekete, Cheick; Verdier, Valerie; Bogdanove, Adam J; Leach, Jan E

    2016-09-01

    The rice pathogens Xanthomonas oryzae pathovar (pv.) oryzae and pv. oryzicola produce numerous transcription activator-like (TAL) effectors that increase bacterial virulence by activating expression of host susceptibility genes. Rice resistance mechanisms against TAL effectors include polymorphisms that prevent effector binding to susceptibility gene promoters, or that allow effector activation of resistance genes. This study identifies, in the heirloom variety Carolina Gold Select, a third mechanism of rice resistance involving TAL effectors. This resistance manifests through strong suppression of disease development in response to diverse TAL effectors from both X. oryzae pathovars. The resistance can be triggered by an effector with only 3.5 central repeats, is independent of the composition of the repeat variable di-residues that determine TAL effector binding specificity, and is independent of the transcriptional activation domain. We determined that the resistance is conferred by a single dominant locus, designated Xo1, that maps to a 1.09 Mbp fragment on chromosome 4. The Xo1 interval also confers complete resistance to the strains in the African clade of X. oryzae pv. oryzicola, representing the first dominant resistance locus against bacterial leaf streak in rice. The strong phenotypic similarity between the TAL effector-triggered resistance conferred by Xo1 and that conferred by the tomato resistance gene Bs4 suggests that monocots and dicots share an ancient or convergently evolved mechanism to recognize analogous TAL effector epitopes. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  1. Development of Hybrid Rice Variety FY7206 with Blast Resistance Gene Pid3 and Cold Tolerance Gene Ctb1

    Directory of Open Access Journals (Sweden)

    Xie Hong-Guang

    2016-09-01

    Full Text Available Hybrid rice Fanyou 7206 (FY7206, derived from the cross between a sterile line Fanyuan A and a restorer line Fuhui 7206, was bred by the Rice Research Institute, Fujian Academy of Agricultural Sciences, China. FY7206 was characterized by moderate blast resistance, cold tolerance, as well as wide adaptability, and high yields. The blast resistance results indicated that the frequencies of blast races in race B, race C and the total resistance frequency for FY7206 were 95.5%, 100.0% and 97.2%, respectively. The disease resistance results showed that the leaf blast grade for FY7206 was level 1 and panicle blast was level 5. The indoor spray results indicated that FY7206 was resistant to 11 isolates of Magnorpathe oryzae. The blast resistance of FY7206 might be derived from the high expression of blast resistance gene Pid3. The results for simulated cold resistance in an artificial climate chamber indicated that the cold tolerance for FY7206 was moderate at the booting and flowering stages. The cold tolerance results also indicated that FY7206 could be tolerant to temperatures as low as 10 °C at the seedling stage. The qRT-PCR results showed that the expression of cold tolerance gene Ctb1 in FY7206 was relatively high. These results suggested that FY7206 is a hybrid indica rice variety with good comprehensive characteristics, including blast resistance and cold tolerance.

  2. Productivity of sodic soils can be enhanced through the use of salt tolerant rice varieties and proper agronomic practices.

    Science.gov (United States)

    Singh, Y P; Mishra, V K; Singh, Sudhanshu; Sharma, D K; Singh, D; Singh, U S; Singh, R K; Haefele, S M; Ismail, A M

    2016-04-01

    Regaining the agricultural potential of sodic soils in the Indo-Gangetic plains necessitates the development of suitable salt tolerant rice varieties to provide an entry for other affordable agronomic and soil manipulation measures. Thus selection of high yielding rice varieties across a range of sodic soils is central. Evaluation of breeding lines through on-station and on-farm farmers' participatory varietal selection (FPVS) resulted in the identification of a short duration (110-115 days), high yielding and disease resistant salt-tolerant rice genotype 'CSR-89IR-8', which was later released as 'CSR43' in 2011. Several agronomic traits coupled with good grain quality and market value contributed to commercialization and quick adoption of this variety in the sodic areas of the Indo-Gangetic plains of eastern India. Management practices required for rice production in salt affected soils are evidently different from those in normal soils and practices for a short duration salt tolerant variety differ from those for medium to long duration varieties. Experiments were conducted at the Indian Council of Agricultural Research-Central Soil Salinity Research Institute (ICAR-CSSRI), Regional Research Station, Lucknow, Uttar Pradesh, India during 2011 and 2013 wet seasons, to test the hypothesis that combining matching management practices (Mmp) with an improved genotype would enhance productivity and profitability of rice in sodic soils. Mmp were developed on-station by optimizing existing best management practices (Bmp) recommended for the region to match the requirements of CSR43. The results revealed that transplanting 4 seedlings hill-1 at a spacing of 15 × 20 cm produced significantly higher yield over other treatments. The highest additional net gain was US$ 3.3 at 90 kg ha-1 N, and the lowest was US$ 0.4 at 150 kg ha-1 N. Above 150 kg ha-1, the additional net gain became negative, indicating decreasing returns from additional N. Hence, 150 kg N ha-1

  3. Characterization of total antioxidant capacity and (poly)phenolic compounds of differently pigmented rice varieties and their changes during domestic cooking.

    Science.gov (United States)

    Zaupa, Maria; Calani, Luca; Del Rio, Daniele; Brighenti, Furio; Pellegrini, Nicoletta

    2015-11-15

    In the recent years, the pigmented rice varieties are becoming more popular due to their antioxidant properties and phenolic content. In this study, we characterized the antioxidant capacity (TAC) and the phenolic profile in white, red and black rice varieties, and evaluated the effect of two cooking methods (i.e. "risotto" and boiling) on these compounds. Before the cooking, all the varieties contained several phenolic acids, whereas anthocyanins and flavonols were peculiar of black rice and flavan-3-ols of red rice. Among the rice varieties, the black had the highest TAC value. The content of (poly)phenolic compounds and TAC decreased after cooking in all three varieties, but to a lesser extent after the risotto method. As a consequence, the risotto cooking, which allows a complete absorption of water, would be a good cooking method to retain (poly)phenolic compounds and TAC in pigmented and non-pigmented whole-meal rice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. A correlation study of proximate composition, physical and cooking properties of new high yielding and disease resistant rice varieties

    Directory of Open Access Journals (Sweden)

    Nuzhat Rasool

    2015-12-01

    Full Text Available The present study was aimed to compare proximate composition, physical, and cooking properties of locally cultivated rice varieties of Kashmir division viz.; SR-1, K-448, and K-39. Various physiochemical properties were studied. The relationship between physical, proximate composition, and cooking properties was determined using Pearson’s correlation. Length–breadth (L/B ratio showed a significant positive correlation with kernel length and negative correlation with thousand kernel weight, with a correlation coefficient (r of 0.893 and −0.855, respectively, (p  0.05. Solid loss in gruel was observed to have a negative correlation with L/B ratio (r = −0.432, p > 0.05, water uptake ratio (r = −0.742, p < 0.05, and cooking time (r = −0.678, p < 0.05. The rice cultivars with higher cooking time showed lower gruel solid loss and vice versa. Water uptake was observed to be positively correlated with L/B ratio (r = 0.768, p < 0.05. Among all the cultivars studied, K-448 variety has potential for consumers’ preference and it could be used for breeding programs for the improvement of valuable grain quality traits.

  5. Identification and quantification of phenolic and flavonoid components in straw and seed husk of some rice varieties (Oryza sativa L.) and their antioxidant properties.

    Science.gov (United States)

    Karimi, Ehsan; Mehrabanjoubani, Pooyan; Keshavarzian, Maryam; Oskoueian, Ehsan; Jaafar, Hawa Z E; Abdolzadeh, Ahmad

    2014-08-01

    Plant foods are rich sources of bioactive compounds that can act as antioxidants to prevent heart disease, reduce inflammation, reduce the incidence of cancers and diabetes. This study aimed to determine the phenolics and flavonoids profiling in three varieties of rice straw and five varieties of the seed husk of Iranian rice using high-performance liquid chromatography (HPLC). Furthermore, the antioxidant activities of the extracts were evaluated by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and nitric oxide assays. HPLC analyses showed that the gallic acid, pyrogallol, apigenin and rutin were the main phenolic and flavonoid compounds in all varieties of rice. In addition, the methanolic extracts of Hashemi and Ali Kazemi varieties showed the highest amounts of phenolic and flavonoid contents, respectively. Rice straw and husk of Iranian varieties showed considerable antioxidant activity and Hashemi indicated significantly (P rice straw and seed husk of Iranian varieties shows high antioxidant activities and they contain various types of phenolic and flavonoid compounds that could be use in food and medical industries. © 2014 Society of Chemical Industry.

  6. Dynamic metabolic responses of brown planthoppers towards susceptible and resistant rice plants.

    Science.gov (United States)

    Liu, Caixiang; Du, Ba; Hao, Fuhua; Lei, Hehua; Wan, Qianfen; He, Guangcun; Wang, Yulan; Tang, Huiru

    2017-10-01

    Brown planthopper (Nilaparvata lugens Stål, BPH) causes huge economic losses in rice-growing regions, and new strategies for combating BPH are required. To understand how BPHs respond towards BPH-resistant plants, we systematically analysed the metabolic differences between BPHs feeding on the resistant and susceptible plants using NMR and GC-FID/MS. We also measured the expression of some related genes involving glycolysis and biosyntheses of trehalose, amino acids, chitin and fatty acids using real-time PCR. BPH metabonome was dominated by more than 60 metabolites including fatty acids, amino acids, carbohydrates, nucleosides/nucleotides and TCA cycle intermediates. After initial 12 h, BPHs feeding on the resistant plants had lower levels of amino acids, glucose, fatty acids and TCA cycle intermediates than on the susceptible ones. The levels of these metabolites recovered after 24 h feeding. This accompanied with increased level in trehalose, choline metabolites and nucleosides/nucleotides compared with BPH feeding on the susceptible plants. Decreased levels of BPH metabolites at the early feeding probably resulted from less BPH uptakes of sap from resistant plants and recovery of BPH metabolites at the later stage probably resulted from their adaptation to the adverse environment with their increased hopping frequency to ingest more sap together with contributions from yeast-like symbionts in BPHs. Throughout 96 h, BPH feeding on the resistant plants showed significant up-regulation of chitin synthase catalysing biosynthesis of chitin for insect exoskeleton, peritrophic membrane lining gut and tracheae. These findings provided useful metabolic information for understanding the BPH-rice interactions and perhaps for developing new BPH-combating strategies. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  7. Comparative study of genes expressed from rice fungus-resistant and susceptible lines during interactions with Magnaporthe oryzae.

    Science.gov (United States)

    Shi, Bu-Jun; Wang, Guo-Liang

    2008-12-31

    Rice blast disease caused by Magnaporthe oryzae is the most important fungal disease of rice. To understand the molecular basis of interaction between the fungus and rice, we constructed a cDNA library from a rice-resistant line inoculated with M. oryzae. One hundred and fifty-three cDNA clones were sequence analyzed, of which 129 exhibited significant nucleotide sequence homology to known genes, 21 were homologous to unknown genes, while three clones did not match to any database. However, these three unmatched clones showed sequence homology at protein level in the protein databases and one of them encoded a disease resistance-related protein kinase and was abundant in the EST collection. Northern analysis showed that this disease resistance-related protein kinase gene was induced by inoculation and only expressed in the rice-resistant, but not susceptible, lines. Southern analysis showed that this gene was present in a single copy in the rice genome and co-segregated with the M. oryzae resistance in the cross of the resistant and susceptible lines. This study illustrates that sequencing of ESTs from inoculated resistant plants can reveal genes responsive to pathogen infection, which could help understand plant defense mechanisms.

  8. Comparative transcriptome profiling of the early response to Magnaporthe oryzae in durable resistant vs susceptible rice (Oryza sativa L. genotypes.

    Directory of Open Access Journals (Sweden)

    Paolo Bagnaresi

    Full Text Available Durable resistance to blast, the most significant fungal disease of rice, represents an agronomically relevant character. Gigante Vercelli (GV and Vialone Nano (VN are two old temperate japonica Italian rice cultivars with contrasting response to blast infection: GV displays durable and broad resistance while VN is highly susceptible. RNA-seq was used to dissect the early molecular processes deployed during the resistance response of GV at 24 h after blast inoculation. Differential gene expression analysis identified 1,070 and 1,484 modulated genes, of which 726 and 699 were up regulated in response to infection in GV and VN, respectively. Gene ontology (GO enrichment analyses revealed a set of GO terms enriched in both varieties but, despite this commonality, the gene sets contributing to common GO enriched terms were dissimilar. The expression patterns of genes grouped in GV-specific enriched GO terms were examined in detail including at the transcript isoform level. GV exhibited a dramatic up-regulation of genes encoding diterpene phytoalexin biosynthetic enzymes, flavin-containing monooxygenase, class I chitinase and glycosyl hydrolase 17. The sensitivity and high dynamic range of RNA-seq allowed the identification of genes critically involved in conferring GV resistance during the early steps of defence perception-signalling. These included chitin oligosaccharides sensing factors, wall associated kinases, MAPK cascades and WRKY transcription factors. Candidate genes with expression patterns consistent with a potential role as GV-specific functional resistance (R gene(s were also identified. This first application of RNA-seq to dissect durable blast resistance supports a crucial role of the prompt induction of a battery of responses including defence-related genes as well as members of gene families involved in signalling and pathogen-related gene expression regulation.

  9. Differential responses of cell wall bound phenolic compounds in sensitive and tolerant varieties of rice in response to salinity.

    Science.gov (United States)

    Gupta, Poulami; De, Bratati

    2017-10-03

    In plants, cell wall bound phenolics change in response to stress. The aim of the study was to investigate the effect of NaCl induced stress on wall bound phenolics in four rice varieties, of which two (Bhutnath, Nonabokra) were salt tolerant and two (MTU 7029, Sujala) were salt sensitive. After germination, seedlings were grown in hydroponic solution and subjected to salinity stress (25 mM, 50 mM, 100 mM and 150 mM NaCl) on day 12. Wall bound phenolic compounds were determined by GC-MS based metabolite analysis. Total seven wall bound phenols were identified from the leaf tissues and eight from the root tissues. Ferulic acid and 4-hydroxycinnamic acid were found in all the four varieties. After NaCl treatment, these two wall bound phenols increased in the leaves of tolerant varieties only. Significant inverse correlation between leaf length and leaf fresh weight with wall bound ferulic acid and 4-hydroxycinnamic acid in Nonabokra suggests the positive role of these wall bound phenolics in salt tolerance.

  10. Comparative Analysis of γ-Oryzanol, β-Glucan, Total Phenolic Content and Antioxidant Activity in Fermented Rice Bran of Different Varieties

    Directory of Open Access Journals (Sweden)

    Tae-Dong Jung

    2017-06-01

    Full Text Available Rice bran, a by-product derived from processing rice, is a rich source of bioactive compounds. Recent studies have suggested that the fermentation can improve their biological activities. This study aimed to determined the level of γ-oryzanol, β-glucan and total phenol contents of fermented rice bran from 21 Korean varieties, as well as to evaluate their antioxidant activities. We also assessed the validation of the analytical method for determining γ-oryzanol content in fermented rice brans. Among the fermented rice brans, the Haedam rice bran contained the highest level of total phenol content (156.08 mg gallic acid equivalents/g, DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (71.30% and ORAC (Oxygen radical absorbance capacity value (1101.31 μM trolox equivalents/g. Furthermore, the fermented Migwang rice bran showed the highest level of γ-oryzanol content (294.77 ± 6.74 mg/100 g.

  11. Status of insecticide susceptibility in Anopheles arabiensis from Mwea rice irrigation scheme, Central Kenya

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    Vulule John M

    2006-06-01

    Full Text Available Abstract Background Control of the Anopheline mosquito vectors of malaria by use of insecticides has been shown to impact on both morbidity and mortality due to this disease. Evidence of insecticide resistance in different settings necessitates surveillance studies to allow prompt detection of resistance should it arise and thus enable its management. Possible resistance by Anopheles arabiensis mosquitoes from Mwea rice irrigation scheme in Central Kenya to insecticides in the four classes of insecticides approved by WHO for indoor residual spraying was investigated. Methods Susceptibility to DDT (an organochlorine, fenitrothion (an organophosphate, bendiocarb (a carbamate, lambdacyhalothrin and permethrin (both pyrethroids was tested using standard WHO diagnostic bioassay kits. Bioassays were performed on non-blood fed mosquitoes one- to three-day old. Knockdown was recorded every 10 min and mortality 24 h post-exposure was noted. Results Mortality 24 h post-exposure was 100% for all insecticides except for lambdacyhalothrin, which averaged 99.46%. Knockdown rates at 10 min intervals were not significantly different between the Mwea population and the susceptible KISUMU strain of Anopheles gambiae sensu stricto control. The KDT50 and KDT95 values for the Mwea population were either lower than those for the control or higher by factors of no more than 2 for most comparisons and compared well with those of An. gambiae sensu lato categorized as susceptible in other studies. Conclusion These results suggest that the Mwea population of An. arabiensis is susceptible to all the insecticides tested. This implies that vector control measures employing any of these insecticides would not be hampered by resistance.

  12. Characterization of QTL for unique agronomic traits of new-plant-type rice varieties using introgression lines of IR64

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    Analiza G. Tagle

    2016-02-01

    Full Text Available To enhance the yield potential of an elite indica rice cultivar, an introgression (BC3-derived line of IR64, YTH288, was developed using a new-plant-type cultivar, IR66215-44-2-3, as a donor parent. YTH288 has agronomically valuable characteristics such as large panicles, few unproductive tillers, and large leaves inherited from NPT. To identify the genetic basis of these traits, we used 167 F2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits: days to heading (DTH, culm length (CL, flag leaf length (FLL, flag leaf width (FLW, and filled spikelet number per panicle (FSN. Six putative QTL were detected: four on chromosome 4 (for CL, FLL, FLW, and FSN and two on chromosome 2 (for DTH and FLL. All QTL with the IR66215-44-2-3 allele, except that for FLL on chromosome 2, had positive effects on each trait. To confirm the effects of these putative QTL, we developed NILs with the IR64 genetic background by marker-assisted selection. We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes 2 and 4. Additionally, four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropic effects for unique agronomic traits. These NILs can be used as research materials for studying each trait and as breeding materials for yield improvement of indica rice cultivars.

  13. Cadmium accumulation in and tolerance of rice (Oryza sativa L.) varieties with different rates of radial oxygen loss

    Energy Technology Data Exchange (ETDEWEB)

    Wang, M.Y. [School of Life Sciences, Sun Yat-sen University, Guangzhou 510006 (China); Chen, A.K. [Department of Biology, Guangdong University of Education, Guangzhou 510303 (China); Wong, M.H. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Hong Kong SAR (China); Qiu, R.L., E-mail: eesqrl@mail.sysu.edu.cn [School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Cheng, H. [School of Life Sciences, Sun Yat-sen University, Guangzhou 510006 (China); Ye, Z.H., E-mail: lssyzhh@mail.sysu.edu.cn [School of Life Sciences, Sun Yat-sen University, Guangzhou 510006 (China)

    2011-06-15

    Cadmium (Cd) uptake and tolerance were investigated among 20 rice cultivars based on a field experiment (1.2 mg Cd kg{sup -1} in soil) and a soil pot trial (control, 100 mg Cd kg{sup -1}), and rates of radial oxygen loss (ROL) were measured under a deoxygenated solution. Significant differences were found among the cultivars in: (1) brown rice Cd concentrations (0.11-0.29 mg kg{sup -1}) in a field soil, (2) grain Cd tolerance (34-113%) and concentrations (2.1-6.5 mg kg{sup -1}) in a pot trial, and (3) rates of ROL (15-31 mmol O{sub 2} kg{sup -1} root d.w. h{sup -1}). Target hazard quotients were calculated for the field experiment to assess potential Cd risk. Significant negative relationships were found between rates of ROL and concentrations of Cd in brown rice or straw under field and greenhouse conditions, indicating that rice cultivars with higher rates of ROL had higher capacities for limiting the transfer of Cd to rice and straw. - Highlights: > There are significant differences in brown rice Cd concentrations and rates of ROL among the rice cultivars. > The rates of ROL are significantly correlated with concentrations of Cd in brown rice. > Rice cultivars with higher rates of ROL have higher capacities for limiting the transfer of Cd to rice and straw. - Rice cultivars with high rates of ROL tended to accumulate low Cd in grains.

  14. Transmission of Rice Black-Streaked Dwarf Virus from Frozen Infected Leaves to Healthy Rice Plants by Small Brown Planthopper (Laodelphax striatellus)

    OpenAIRE

    Zhou, Tong; Wu, Li-juan; Wang, Ying; Cheng, Zhao-Bang; Ji, Ying-Hua; Yong-jian FAN; Zhou, Yi-Jun

    2011-01-01

    In order to preserve virus for identifying the resistance of rice varieties against rice black-streaked dwarf disease, a simple and reliable method was developed, through which virus-free small brown planthopper (SBPH) acquired rice black-streaked dwarf virus (RBSDV) from frozen infected leaves and the virus was transmitted to healthy rice plants. The experimental results showed that SBPH could obtain RBSDV from frozen infected rice leaves and the virus could be transmitted to a susceptible r...

  15. Effects of water-saving irrigation practices and drought resistant rice variety on greenhouse gas emissions from a no-till paddy in the central lowlands of China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Ying; Ge, Junzhu; Tian, Shaoyang; Li, Shuya [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Nguy-Robertson, Anthony L. [Center for Advanced Land Management Information Technologies, School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE 68583-0973 (United States); Zhan, Ming, E-mail: zhanming@mail.hzau.edu.cn [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Cao, Cougui, E-mail: ccgui@mail.hzau.edu.cn [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China)

    2015-02-01

    As pressure on water resources increases, alternative practices to conserve water in paddies have been developed. Few studies have simultaneously examined the effectiveness of different water regimes on conserving water, mitigating greenhouse gases (GHG), and maintaining yields in rice production. This study, which was conducted during the drought of 2013, examined all three factors using a split-plot experiment with two rice varieties in a no-till paddy managed under three different water regimes: 1) continuous flooding (CF), 2) flooded and wet intermittent irrigation (FWI), and 3) flooded and dry intermittent irrigation (FDI). The Methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions were measured using static chamber-gas measurements, and the carbon dioxide (CO{sub 2}) emissions were monitored using a soil CO{sub 2} flux system (LI-8100). Compared with CF, FWI and FDI irrigation strategies reduced CH{sub 4} emissions by 60% and 83%, respectively. In contrast, CO{sub 2} and N{sub 2}O fluxes increased by 65% and 9%, respectively, under FWI watering regime and by 104% and 11%, respectively, under FDI managed plots. Although CO{sub 2} and N{sub 2}O emissions increased, the global warming potential (GWP) and greenhouse gas intensity (GHGI) of all three GHG decreased by up to 25% and 29% (p < 0.01), respectively, using water-saving irrigation strategies. The rice variety also affected yields and GHG emissions in response to different water regimes. The drought-resistance rice variety (HY3) was observed to maintain yields, conserve water, and reduce GHG under the FWI irrigation management compared with the typical variety (FYY299) planted in the region. The FYY299 only had significantly lower GWP and GHGI when the yield was reduced under FDI water regime. In conclusion, FWI irrigation strategy could be an effective option for simultaneously saving water and mitigating GWP without reducing rice yields using drought-resistant rice varieties, such as HY3

  16. Comparative analysis of Histone modifications and DNA methylation at OsBZ8 locus under salinity stress in IR64 and Nonabokra rice varieties.

    Science.gov (United States)

    Paul, Amit; Dasgupta, Pratiti; Roy, Dipan; Chaudhuri, Shubho

    2017-09-01

    Rice being an important cereal crop is highly sensitive to salinity stress causing growth retardation and loss in productivity. However, certain rice genotypes like Nonabokra and Pokkali show a high level of tolerance towards salinity stress compared to IR64 variety. This differential response of tolerant varieties towards salinity stress may be a cumulative effect of genetic and epigenetic factors. In this study, we have compared the salinity-induced changes in chromatin modifications at the OsBZ8 locus in salt-tolerant Nonabokra and salt-sensitive IR64 rice varieties. Expression analysis indicates that the OsBZ8 gene is highly induced in Nonabokra plants even in the absence of salt stress, whereas in IR64, the expression significantly increases only during salt stress. Sequence analysis and nucleosomal arrangement within the region -2000 to +1000 of OsBZ8 gene show no difference between the two rice varieties. However, there was a considerable difference in histone modifications and DNA methylation at the locus between these varieties. In Nonabokra, the upstream region was hyperacetylated at H3K9 and H3K27, and this acetylation did not change during salt stress. However, in IR64, histone acetylation was observed only during salt stress. Moreover, the upstream region of OsBZ8 gene has highly dynamic nucleosome arrangement in Nonabokra, compared to IR64. Furthermore, loss of DNA methylation was observed at OsBZ8 locus in Nonabokra control plants along with low H3K27me3 and high H3K4me3. Control IR64 plants show high DNA methylation and enriched H3K27me3. Collectively these results indicate a significant difference in chromatin modifications between the rice varieties that regulates differential expression of OsBZ8 gene during salt stress.

  17. Nutrient uptake of NPK and result of some rice varieties in tidal land by using combination of organic and inorganic fertilizer

    Science.gov (United States)

    Marlina, Neni; Rompas, Joni Phillep; Marlina, Musbik

    2017-09-01

    Rice planting in tidal land has two main problems: iron (Fe) which has the potential to poison rice and low nutrient availability. Azospirillum enriched chicken manure and phosphate solvent bacteria (Biological Organic Fertilizer = BOF) is an option to overcome iron toxicity and as a source of nutrition. The objective of the study was to obtain a combination of biological organic fertilizers and balanced inorganic fertilizers in reducing doses of inorganic fertilizers, increasing NPK nutrient uptake and yield of several rice varieties in tidal land. This research used Factorial RAK with 25 treatment combinations that were repeated three times. Factor I is a combination of BOF and anorganic fertilizer with 5 levels of treatment (no inorganic fertilizers, BOF 400 kg / ha with inorganic fertilizer 25% NPK, BOF 400 kg / ha with inorganic fertilizer 50% NPK and BOF 400 kg / ha with fertilizer Inorganic 75% NPK). Factor II is several rice varieties (IPB 4S, Martapura, Margasari, Inpara 5, Inpara 7). The results showed that organic fertilizer 400 kg / ha can reduce the use of inorganic fertilizer by 75% of NPK fertilizer. The highest NPK nutrient absorption is in the treatment of organic fertilizer 400 kg / ha and inorganic fertilizer 25% of NPK fertilizer. Production of biological organic fertilizer 400 kg / ha with inorganic fertilizer 25% NPK and 4B IPB varieties 727.77% higher when compared with without the provision of organic fertilizer with Inpara 5 varieties.

  18. Growth performance, productivity and diseases susceptibility of barley varieties in Slovenia within the Cobra project’s site comparison

    Directory of Open Access Journals (Sweden)

    Grobelnik Mlakar Silva

    2016-12-01

    Full Text Available Different plant genotypes react differently in different climates. A field experiment was carried out to estimate the growth performance, productivity and diseases susceptibility of spring barley varieties in the Slovenian climate. We received some varieties, mainly of Nordic origin, from the Technical University of Denmark, a COBRA project partner, which were previously tested in estimated future climate in RERAF phytotron. Varieties of the highest grain yield (3,993 kg ha-1 in ‘Evergreen’ to 5,146 kg ha-1 in ‘Sebastian’ were rather shorter (58.7 cm to 67.1 cm and mostly had the highest specific grain weight (54.3 to 58.6 kg 100 L-1 and 1000-kernel weight (30.2 to 37.1 g. They developed 1,561 to 2,532 tillers m-2 and 515 to 840 ears m-2 and reached a heading stage between 13th and 25th of May. The tested varieties seem rather insusceptible to most common diseases, but susceptible to cereal leaf beetle attacks.

  19. Physiological Mechanisms Underlying the High-Grain Yield and High-Nitrogen Use Efficiency of Elite Rice Varieties under a Low Rate of Nitrogen Application in China

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    Lilian Wu

    2016-07-01

    Full Text Available Selecting rice varieties with a high nitrogen (N use efficiency (NUE is the best approach to reduce N fertilizer application in rice production and is one of the objectives of the Green Super Rice (GSR Project in China. However, the performance of elite candidate GSR varieties under low N supply remains unclear. In the present study, differences in the grain yield and NUE of thirteen and fourteen candidate varieties with two controls were determined at a N rate of 100 kg ha-1 in field experiments in 2014 and 2015, respectively. The grain yield for all of the rice varieties ranged from 8.67 to 11.09 t ha-1, except for a japonica rice variety YG29, which had a grain yield of 6.42 t ha-1. HY549 and YY4949 produced the highest grain yield, reflecting a higher biomass production and harvest index in 2014 and 2015, respectively. Total N uptake at maturity (TNPM ranged from 144 to 210 kg ha-1, while the nitrogen use efficiency for grain production (NUEg ranged from 35.2 to 62.0 kg kg-1. Both TNPM and NUEg showed a significant quadratic correlation with grain yield, indicating that it is possible to obtain high grain yield and NUEg with the reduction of TNPM. The correlation between N-related parameters and yield-related traits suggests that promoting pre-heading growth could increase TNPM, while high biomass accumulation during the grain filling period and large panicles are important for a higher NUEg. In addition, there were significant and negative correlations between the NUEg and N concentrations in leaf, stem and grain tissues at maturity. Further improvements in NUEg require a reduction in the stem N concentration but not the leaf N concentration. The daily grain yield was the only parameter that significantly and positively correlated with both TNPM and NUEg. This study determined variations in the grain yield and NUE of elite candidate GSR rice varieties and provided plant traits that could be used as selection criteria in breeding N

  20. RNA interference knockdown of aminopeptidase N genes decrease the susceptibility of Chilo suppressalis larvae to Cry1Ab/Cry1Ac and Cry1Ca-expressing transgenic rice.

    Science.gov (United States)

    Qiu, Lin; Fan, Jinxing; Zhang, Boyao; Liu, Lang; Wang, Xiaoping; Lei, Chaoliang; Lin, Yongjun; Ma, Weihua

    2017-05-01

    Transgenic rice expressing Bacillus thuringiensis (Bt) Cry toxins are resistant to lepidopteran pests, such as Chilo suppressalis, a major insect pest of rice in Asia. Understanding how these toxins interact with their hosts is crucial to understanding their insecticidal action. In this study, knockdown of two aminopeptidase N genes (APN1 and APN2) by RNA interference resulted in decreased susceptibility of C. suppressalis larvae to the Bt rice varieties TT51 (Cry1Ab and Cry1Ac fusion genes) and T1C-19 (Cry1Ca), but not T2A-1 (Cry2Aa). This suggests that APN1 and APN2 are receptors for Cry1A and Cry1C toxins in C. suppressalis. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Relative susceptibility of two sweetpotato varieties to storage root damage by sweetpotato flea beetle (Coleoptera: Chrysomelidae) and wireworm (Coleoptera: Elateridae).

    Science.gov (United States)

    Abney, Mark R; Kennedy, George G

    2011-02-01

    The feeding of soil dwelling insects on storage roots is one of the most serious management issues faced by sweetpotato, Ipomoea batatas (L.) Lam. (Convolvulaceae), growers in the southern United States. Field studies were conducted to evaluate the relative susceptibility of two commonly grown sweetpotato varieties to sweetpotato flea beetle, Chaetocnema confinis Crotch (Coleoptera: Chrysomelidae), and wireworms (Coleoptera: Elateridae, various species). The incidence and severity of sweetpotato flea beetle damage was significantly lower in the variety Covington than Beauregard in two small plot replicated studies. Surveys conducted in commercial sweetpotato fields also showed significantly less sweetpotato flea beetle damage in fields planted to Covington compared with those planted to Beauregard. There was no clear evidence of varietal effect on the incidence of wireworm damage in the study. Results indicate that the severity of wireworm damage as measured by the size of feeding scars may be less in Covington than Beauregard.

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

    Science.gov (United States)

    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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Identification of four functionally important microRNA families with contrasting differential expression profiles between drought-tolerant and susceptible rice leaf at vegetative stage.

    Science.gov (United States)

    Cheah, Boon Huat; Nadarajah, Kalaivani; Divate, Mayur Dashrath; Wickneswari, Ratnam

    2015-09-15

    Developing drought-tolerant rice varieties with higher yield under water stressed conditions provides a viable solution to serious yield-reduction impact of drought. Understanding the molecular regulation of this polygenic trait is crucial for the eventual success of rice molecular breeding programmes. microRNAs have received tremendous attention recently due to its importance in negative regulation. In plants, apart from regulating developmental and physiological processes, microRNAs have also been associated with different biotic and abiotic stresses. Hence here we chose to analyze the differential expression profiles of microRNAs in three drought treated rice varieties: Vandana (drought-tolerant), Aday Sel (drought-tolerant) and IR64 (drought-susceptible) in greenhouse conditions via high-throughput sequencing. Twenty-six novel microRNA candidates involved in the regulation of diverse biological processes were identified based on the detection of miRNA*. Out of their 110 predicted targets, we confirmed 16 targets from 5 novel microRNA candidates. In the differential expression analysis, mature microRNA members from 49 families of known Oryza sativa microRNA were differentially expressed in leaf and stem respectively with over 28 families having at least a similar mature microRNA member commonly found to be differentially expressed between both tissues. Via the sequence profiling data of leaf samples, we identified osa-miR397a/b, osa-miR398b, osa-miR408-5p and osa-miR528-5p as being down-regulated in two drought-tolerant rice varieties and up-regulated in the drought-susceptible variety. These microRNAs are known to be involved in regulating starch metabolism, antioxidant defence, respiration and photosynthesis. A wide range of biological processes were found to be regulated by the target genes of all the identified differentially expressed microRNAs between both tissues, namely root development (5.3-5.7 %), cell transport (13.2-18.4 %), response to stress (10

  4. The influence of plant spacing in the early stages of selection of rice (Oryza sativa L. varieties

    Directory of Open Access Journals (Sweden)

    Isabel Torró

    2016-06-01

    Full Text Available The cultural practices of the early generations in a pedigree breeding programme may influence its success. The main objective of this study was to compare two selection environments in rice: Widely spaced planting in the field and dense planting in concrete basins. Both methods had yielded commercial varieties in the past. Two F2 populations (J and MS, derived from two crosses sharing the same female parent, were transplanted to both environments. Phenotypic traits were evaluated and their narrow sense heritabilities (h2 estimated in the F3 and in the F4 progenies of selected plants, all grown in the field. Growth potential was more apparent in the field for most traits, especially those related to yield, but broad sense heritabilities were higher in the basins for ten traits, being higher in the field for the other five. In population F2MS, field selection resulted in F3 plants which retained a higher tillering ability than those derived from basins selection. Most traits showed low h2 values: Additive variance was only relevant in panicle length (in both populations, plant height and mean panicle weight (in the J population. However, response to one generation of selection (from F3 to F4 also showed fixable variation in panicle number. In addition, this selection reduced plant height, increased culm diameter and internode length (in both populations, and improved pulling resistance (against lodging in population J. It may be concluded that both practices can be used for selection in the F2, although different responses might be expected in yield related traits.

  5. The influence of plant spacing in the early stages of selection of rice (Oryza sativa L.) varieties

    Energy Technology Data Exchange (ETDEWEB)

    Torró, I.; Bretó, P.; García-Yzaguirre, A.

    2016-11-01

    The cultural practices of the early generations in a pedigree breeding programme may influence its success. The main objective of this study was to compare two selection environments in rice: Widely spaced planting in the field and dense planting in concrete basins. Both methods had yielded commercial varieties in the past. Two F2 populations (J and MS), derived from two crosses sharing the same female parent, were transplanted to both environments. Phenotypic traits were evaluated and their narrow sense heritabilities (h2) estimated in the F3 and in the F4 progenies of selected plants, all grown in the field. Growth potential was more apparent in the field for most traits, especially those related to yield, but broad sense heritabilities were higher in the basins for ten traits, being higher in the field for the other five. In population F2MS, field selection resulted in F3 plants which retained a higher tillering ability than those derived from basins selection. Most traits showed low h2 values: Additive variance was only relevant in panicle length (in both populations), plant height and mean panicle weight (in the J population). However, response to one generation of selection (from F3 to F4) also showed fixable variation in panicle number. In addition, this selection reduced plant height, increased culm diameter and internode length (in both populations), and improved pulling resistance (against lodging) in population J. It may be concluded that both practices can be used for selection in the F2, although different responses might be expected in yield related traits. (Author)

  6. Transmission of Rice Black-Streaked Dwarf Virus from Frozen Infected Leaves to Healthy Rice Plants by Small Brown Planthopper (Laodelphax striatellus

    Directory of Open Access Journals (Sweden)

    Tong ZHOU

    2011-06-01

    Full Text Available In order to preserve virus for identifying the resistance of rice varieties against rice black-streaked dwarf disease, a simple and reliable method was developed, through which virus-free small brown planthopper (SBPH acquired rice black-streaked dwarf virus (RBSDV from frozen infected leaves and the virus was transmitted to healthy rice plants. The experimental results showed that SBPH could obtain RBSDV from frozen infected rice leaves and the virus could be transmitted to a susceptible rice variety. For the ability to acquire RBSDV and transmit the virus to healthy plants by SBPH, there was no significant difference between frozen infected leaves and in vitro infected leaves. The novel method could be applied to identification of rice variety resistance to rice black-streaked dwarf disease, facilitating the breeding process for rice black-streaked dwarf disease resistance.

  7. Effect of nano packaging on preservation quality of Nanjing 9108 rice variety at high temperature and humidity.

    Science.gov (United States)

    Wang, Fan; Hu, Qiuhui; Mugambi Mariga, Alfred; Cao, Chongjiang; Yang, Wenjian

    2018-01-15

    A nano packaging material containing nano Ag, nano TiO2, nano attapulgite and SiO2 was prepared, and its impact on quality of Nanjing 9108 rice at 37°C and 85% relative humidity was studied. Effects of the packaging on ambient gases and chromatic aberration of rice were determined. Moreover, oxidation level, molds growth and flavor of rice were also analyzed. Results showed that nano packaging material had antimicrobial effects and maintained low O2 and high CO2 content in the packages. The packages thereby inhibited the growth of molds and the production of fatty acids, restrained the increase of lipase activity, and reduced the oxidation of fats and proteins. As a result, the production of yellow and white-belly rice were inhibited. Furthermore, the color and flavor of rice were maintained. Therefore, the nano-packing material could be applied for preservation of rice to improve preservation quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Extensive sequence divergence between the reference genomes of two elite indica rice varieties Zhenshan 97 and Minghui 63.

    Science.gov (United States)

    Zhang, Jianwei; Chen, Ling-Ling; Xing, Feng; Kudrna, David A; Yao, Wen; Copetti, Dario; Mu, Ting; Li, Weiming; Song, Jia-Ming; Xie, Weibo; Lee, Seunghee; Talag, Jayson; Shao, Lin; An, Yue; Zhang, Chun-Liu; Ouyang, Yidan; Sun, Shuai; Jiao, Wen-Biao; Lv, Fang; Du, Bogu; Luo, Meizhong; Maldonado, Carlos Ernesto; Goicoechea, Jose Luis; Xiong, Lizhong; Wu, Changyin; Xing, Yongzhong; Zhou, Dao-Xiu; Yu, Sibin; Zhao, Yu; Wang, Gongwei; Yu, Yeisoo; Luo, Yijie; Zhou, Zhi-Wei; Hurtado, Beatriz Elena Padilla; Danowitz, Ann; Wing, Rod A; Zhang, Qifa

    2016-08-30

    Asian cultivated rice consists of two subspecies: Oryza sativa subsp. indica and O. sativa subsp. japonica Despite the fact that indica rice accounts for over 70% of total rice production worldwide and is genetically much more diverse, a high-quality reference genome for indica rice has yet to be published. We conducted map-based sequencing of two indica rice lines, Zhenshan 97 (ZS97) and Minghui 63 (MH63), which represent the two major varietal groups of the indica subspecies and are the parents of an elite Chinese hybrid. The genome sequences were assembled into 237 (ZS97) and 181 (MH63) contigs, with an accuracy >99.99%, and covered 90.6% and 93.2% of their estimated genome sizes. Comparative analyses of these two indica genomes uncovered surprising structural differences, especially with respect to inversions, translocations, presence/absence variations, and segmental duplications. Approximately 42% of nontransposable element related genes were identical between the two genomes. Transcriptome analysis of three tissues showed that 1,059-2,217 more genes were expressed in the hybrid than in the parents and that the expressed genes in the hybrid were much more diverse due to their divergence between the parental genomes. The public availability of two high-quality reference genomes for the indica subspecies of rice will have large-ranging implications for plant biology and crop genetic improvement.

  9. A comparison of aquaporin function in mediating stomatal aperture gating among drought-tolerant and sensitive varieties of rice (Oryza sativa L.).

    Science.gov (United States)

    Vinnakota, Rajesh; Ramakrishnan, Anantha Maharasi; Samdani, A; Venugopal, M Anjali; Ram, B Sri; Krishnan, S Navaneetha; Murugesan, Dhandapani; Sankaranarayanan, Kavitha

    2016-11-01

    Climate change drastically affects the cultivation of rice, and its production is affected significantly by water stress. Adaptation of a plant to water deficit conditions is orchestrated by efficient water uptake and a stringently regulated water loss. Transpiration remains the major means of water loss from plants and is mediated by microscopic pores called stomata. Stomatal aperture gating is facilitated by ion channels and aquaporins (AQPs) which regulate the turgidity of the guard cells. In a similar manner, efficient water uptake by the roots is regulated by the presence of AQPs in the plasma membrane of root cells. In this study, we compare the efficiency of transmembrane water permeability in guard cells and root protoplasts from drought-tolerant and sensitive varieties of Oryza sativa L. In this report, we studied the transmembrane osmotic water permeability (Pos) of guard cell and root protoplasts of drought-sensitive and tolerant cultivars. The guard cells isolated from the drought-sensitive lowland rice variety ADT-39 show significant low osmotic permeability than the drought-tolerant rice varieties of Anna (lowland) and Dodda Byra Nellu (DBN) (upland local land rice). There is no significant difference in relative gene expression patterns of PIPs (Plasma membrane Intrinsic Proteins "PIP1" and "PIP2" subfamilies) in guard cells isolated from ADT-39 and Anna. While the expression levels of AQP genes remain the same between ADT-39 and Anna, there is a drastic difference in their osmotic permeability in the guard cells in spite of a higher number of stomata in Anna and DBN, hinting at a more efficient gating mechanism of AQP in the stomata of the drought-tolerant varieties studied.

  10. Grain Yield, Dry Weight and Phosphorus Accumulation and Translocation in Two Rice (Oryza sativa L. Varieties as Affected by Salt-Alkali and Phosphorus

    Directory of Open Access Journals (Sweden)

    Zhijie Tian

    2017-08-01

    Full Text Available Salt-alkali is the main threat to global crop production. The functioning of phosphorus (P in alleviating damage to crops from saline-alkaline stress may be dependent on the variety of crop but there is little published research on the topic. This pot experiment was conducted to study if P has any effect on rice (Oryza sativa L. yield, dry matter and P accumulation and translocation in salt-alkaline soils. Plant dry weight and P content at heading and harvest stages of two contrasting saline-alkaline tolerant (Dongdao-4 and sensitive (Tongyu-315 rice varieties were examined under two saline-alkaline (light versus severe soils and five P supplements (P0, P50, P100, P150 and P200 kg ha−1. The results were: in light saline-alkaline soil, the optimal P levels were found for P150 for Dongdao-4 and for P100 for Tongyu-315 with the greatest grain dry weight and P content. Two rice varieties obtained relatively higher dry weight and P accumulation and translocation in P0. In severe saline-alkaline soil, however, dry weight and P accumulation and translocation, 1000-grain weight, seed-setting rate and grain yield significantly decreased, but effectively increased with P application for Dongdao-4. Tongyu-315 showed lower sensitivity to P nutrition. Thus, a more tolerant variety could have a stronger capacity to absorb and translocate P for grain filling, especially in severe salt-alkaline soils. This should be helpful for consideration in rice breeding and deciding a reasonable P application in saline-alkaline soil.

  11. Role of gamma-oryzanol in drought-tolerant and susceptible cultivars of rice (Oryza sativa L.).

    Science.gov (United States)

    Kumar, M S Sujith; Dahuja, Anil; Rai, R D; Walia, Suresh; Tyagi, Aruna

    2014-02-01

    Drought-tolerant cultivars and their phytochemical composition, which has a role in providing drought tolerance are gaining importance. In this study, rice bran oil and semi-purified oryzanol (SPO) obtained from five rice (Oryza sativa L.) cultivars, namely P1401 and PB1 (drought-susceptible) and N22, PNR381 and APO (drought-tolerant) were analyzed for the gamma-oryzanol content, an antioxidant present in considerable amount in the rice bran. The higher level of gamma-oryzanol and its antioxidant activity was observed in drought-tolerant cultivars (N22, PNR381 and APO) as compared to drought-susceptible (PB1 and P1401), suggesting the role of gamma-oryzanol in drought tolerance, as antioxidants are known to play an important role by scavenging free radicals. The total antioxidant activity of gamma-oryzanol might be attributed to 24-methylene cycloartanyl ferulate, a major component of gamma-oryzanol. By enhancing the level of active oryzanol components identified in this study by genetic and molecular means could impart increased drought tolerance.

  12. Transcriptome-Based Identification of Differently Expressed Genes from Xanthomonas oryzae pv. oryzae Strains Exhibiting Different Virulence in Rice Varieties.

    Science.gov (United States)

    Noh, Tae-Hwan; Song, Eun-Sung; Kim, Hong-Il; Kang, Mi-Hyung; Park, Young-Jin

    2016-02-19

    Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB) in rice (Oryza sativa L.). In this study, we investigated the genome-wide transcription patterns of two Xoo strains (KACC10331 and HB1009), which showed different virulence patterns against eight rice cultivars, including IRBB21 (carrying Xa21). In total, 743 genes showed a significant change (p-value 2) in the HB1009 (K3a race) strain than in the Xoo KACC10331 (K1 race) strain. Furthermore, 13 and 12 genes involved in hypersensitive response and pathogenicity (hrp) and two-component regulatory systems (TCSs), respectively, were upregulated in the HB1009 (K3a race) strain compared with the Xoo KACC10331 (K1 race) strain, which we determined using either quantitative real-time PCR analysis or next-generation RNA sequencing. These results will be helpful to improve our understanding of Xoo and to gain a better insight into the Xoo-rice interactions.

  13. Integrative Analysis of the microRNAome and Transcriptome Illuminates the Response of Susceptible Rice Plants to Rice Stripe Virus.

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    Jian Yang

    Full Text Available Rice stripe virus (RSV is one of the most serious rice viruses in East Asia. To investigate how rice responds to RSV infection, we integrated miRNA expression with parallel mRNA transcription profiling by deep sequencing. A total of 570 miRNAs were identified of which 69 miRNAs (56 up-regulated and 13 down-regulated were significantly modified by RSV infection. Digital gene expression (DGE analysis showed that 1274 mRNAs (431 up-regulated and 843 down-regulated genes were differentially expressed as a result of RSV infection. The differential expression of selected miRNAs and mRNAs was confirmed by qRT-PCR. Gene ontology (GO and pathway enrichment analysis showed that a complex set of miRNA and mRNA networks were selectively regulated by RSV infection. In particular, 63 differentially expressed miRNAs were found to be significantly and negatively correlated with 160 target mRNAs. Interestingly, 22 up-regulated miRNAs were negatively correlated with 24 down-regulated mRNAs encoding disease resistance-related proteins, indicating that the host defense responses were selectively suppressed by RSV infection. The suppression of both osa-miR1423-5p- and osa-miR1870-5p-mediated resistance pathways was further confirmed by qRT-PCR. Chloroplast functions were also targeted by RSV, especially the zeaxanthin cycle, which would affect the stability of thylakoid membranes and the biosynthesis of ABA. All these modifications may contribute to viral symptom development and provide new insights into the pathogenicity mechanisms of RSV.

  14. Expression Profiling of Abiotic Stress-Inducible Genes in response to Multiple Stresses in Rice (Oryza sativa L. Varieties with Contrasting Level of Stress Tolerance

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    Supratim Basu

    2014-01-01

    Full Text Available The present study considered transcriptional profiles and protein expression analyses from shoot and/or root tissues under three abiotic stress conditions, namely, salinity, dehydration, and cold, as well as following exogenous abscisic acid treatment, at different time points of stress exposure in three indica rice varieties, IR-29 (salt sensitive, Pokkali, and Nonabokra (both salt tolerant. The candidate genes chosen for expression studies were HKT-1, SOS-3, NHX-1, SAPK5, SAPK7, NAC-1, Rab16A, OSBZ8, DREBP2, CRT/DREBP, WRKY24, and WRKY71, along with the candidate proteins OSBZ8, SAMDC, and GST. Gene expression profile revealed considerable differences between the salt-sensitive and salt-tolerant rice varieties, as the expression in the latter was higher even at the constitutive level, whereas it was inducible only by corresponding stress signals in IR-29. Whether in roots or shoots, the transcriptional responses to different stressors peaked following 24 h of stress/ABA exposure, and the transcript levels enhanced gradually with the period of exposure. The generality of stress responses at the transcriptional level was therefore time dependent. Heat map data also showed differential transcript abundance in the three varieties, correlating the observation with transcript profiling. In silico analysis of the upstream regions of all the genes represented the existence of conserved sequence motifs in single or multiple copies that are indispensable to abiotic stress response. Overall, the transcriptome and proteome analysis undertaken in the present study indicated that genes/proteins conferring tolerance, belonging to different functional classes, were overrepresented, thus providing novel insight into the functional basis of multiple stress tolerance in indica rice varieties. The present work will pave the way in future to select gene(s for overexpression, so as to generate broad spectrum resistance to multiple stresses simultaneously.

  15. silencing COI1 in rice increases susceptibility to chewing insects and impairs inducible defense.

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    Mao Ye

    Full Text Available The jasmonic acid (JA pathway plays a key role in plant defense responses against herbivorous insects. CORONATINE INSENSITIVE1 (COI1 is an F-box protein essential for all jasmonate responses. However, the precise defense function of COI1 in monocotyledonous plants, especially in rice (Oryza sativa L. is largely unknown. We silenced OsCOI1 in rice plants via RNA interference (RNAi to determine the role of OsCOI1 in rice defense against rice leaf folder (LF Cnaphalocrocis medinalis, a chewing insect, and brown planthopper (BPH Nilaparvata lugens, a phloem-feeding insect. In wild-type rice plants (WT, the transcripts of OsCOI1 were strongly and continuously up-regulated by LF infestation and methyl jasmonate (MeJA treatment, but not by BPH infestation. The abundance of trypsin protease inhibitor (TrypPI, and the enzymatic activities of polyphenol oxidase (PPO and peroxidase (POD were enhanced in response to both LF and BPH infestation, but the activity of lipoxygenase (LOX was only induced by LF. The RNAi lines with repressed expression of OsCOI1 showed reduced resistance against LF, but no change against BPH. Silencing OsCOI1 did not alter LF-induced LOX activity and JA content, but it led to a reduction in the TrypPI content, POD and PPO activity by 62.3%, 48.5% and 27.2%, respectively. In addition, MeJA-induced TrypPI and POD activity were reduced by 57.2% and 48.2% in OsCOI1 RNAi plants. These results suggest that OsCOI1 is an indispensable signaling component, controlling JA-regulated defense against chewing insect (LF in rice plants, and COI1 is also required for induction of TrypPI, POD and PPO in rice defense response to LF infestation.

  16. Molecular and Functional Characterization of GR2-R1 Event Based Backcross Derived Lines of Golden Rice in the Genetic Background of a Mega Rice Variety Swarna.

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    Haritha Bollinedi

    Full Text Available Homozygous Golden Rice lines developed in the background of Swarna through marker assisted backcross breeding (MABB using transgenic GR2-R1 event as a donor for the provitamin A trait have high levels of provitamin A (up to 20 ppm but are dwarf with pale green leaves and drastically reduced panicle size, grain number and yield as compared to the recurrent parent, Swarna. In this study, we carried out detailed morphological, biochemical and molecular characterization of these lines in a quest to identify the probable reasons for their abnormal phenotype. Nucleotide blast analysis with the primer sequences used to amplify the transgene revealed that the integration of transgene disrupted the native OsAux1 gene, which codes for an auxin transmembrane transporter protein. Real time expression analysis of the transgenes (ZmPsy and CrtI driven by endosperm-specific promoter revealed the leaky expression of the transgene in the vegetative tissues. We propose that the disruption of OsAux1 disturbed the fine balance of plant growth regulators viz., auxins, gibberellic acid and abscisic acid, leading to the abnormalities in the growth and development of the lines homozygous for the transgene. The study demonstrates the conserved roles of OsAux1 gene in rice and Arabidopsis.

  17. Molecular and Functional Characterization of GR2-R1 Event Based Backcross Derived Lines of Golden Rice in the Genetic Background of a Mega Rice Variety Swarna.

    Science.gov (United States)

    Bollinedi, Haritha; S, Gopala Krishnan; Prabhu, Kumble Vinod; Singh, Nagendra Kumar; Mishra, Sushma; Khurana, Jitendra P; Singh, Ashok Kumar

    2017-01-01

    Homozygous Golden Rice lines developed in the background of Swarna through marker assisted backcross breeding (MABB) using transgenic GR2-R1 event as a donor for the provitamin A trait have high levels of provitamin A (up to 20 ppm) but are dwarf with pale green leaves and drastically reduced panicle size, grain number and yield as compared to the recurrent parent, Swarna. In this study, we carried out detailed morphological, biochemical and molecular characterization of these lines in a quest to identify the probable reasons for their abnormal phenotype. Nucleotide blast analysis with the primer sequences used to amplify the transgene revealed that the integration of transgene disrupted the native OsAux1 gene, which codes for an auxin transmembrane transporter protein. Real time expression analysis of the transgenes (ZmPsy and CrtI) driven by endosperm-specific promoter revealed the leaky expression of the transgene in the vegetative tissues. We propose that the disruption of OsAux1 disturbed the fine balance of plant growth regulators viz., auxins, gibberellic acid and abscisic acid, leading to the abnormalities in the growth and development of the lines homozygous for the transgene. The study demonstrates the conserved roles of OsAux1 gene in rice and Arabidopsis.

  18. Hydraulic conductance as well as nitrogen accumulation plays a role in the higher rate of leaf photosynthesis of the most productive variety of rice in Japan

    Science.gov (United States)

    Taylaran, Renante D.; Adachi, Shunsuke; Ookawa, Taiichiro; Usuda, Hideaki; Hirasawa, Tadashi

    2011-01-01

    An indica variety Takanari is known as one of the most productive rice varieties in Japan and consistently produces 20–30% heavier dry matter during ripening than Japanese commercial varieties in the field. The higher rate of photosynthesis of individual leaves during ripening has been recognized in Takanari. By using pot-grown plants under conditions of minimal mutual shading, it was confirmed that the higher rate of leaf photosynthesis is responsible for the higher dry matter production after heading in Takanari as compared with a japonica variety, Koshihikari. The rate of leaf photosynthesis and shoot dry weight became larger in Takanari after the panicle formation and heading stages, respectively, than in Koshihikari. Roots grew rapidly in the panicle formation stage until heading in Takanari compared with Koshihikari. The higher rate of leaf photosynthesis in Takanari resulted not only from the higher content of leaf nitrogen, which was caused by its elevated capacity for nitrogen accumulation, but also from higher stomatal conductance. When measured under light-saturated conditions, stomatal conductance was already decreased due to the reduction in leaf water potential in Koshihikari even under conditions of a relatively small difference in leaf–air vapour pressure difference. In contrast, the higher stomatal conductance was supported by the maintenance of higher leaf water potential through the higher hydraulic conductance in Takanari with the larger area of root surface. However, no increase in root hydraulic conductivity was expected in Takanari. The larger root surface area of Takanari might be a target trait in future rice breeding for increasing dry matter production. PMID:21527630

  19. Susceptibility of gerbera and chrysanthemum varieties (Gerbera jamesoni and Chrysanthemum morifolium) to Fusarium oxysporum f.sp. chrysanthemi.

    Science.gov (United States)

    Minuto, Andrea; Gullino, Lodovica Maria; Garibaldi, Angelo

    2007-01-01

    In 2002, gerbera plants (cv Kaliki) were observed exhibiting symptoms of a wilt in a soilless cultivation at Albenga area (Northern Italy). A similar wilt was also observed in the Sanremo area (Northern Italy) on cv Red Bull, Anedin and Gud finger grown in soil. The same observations were carried out in 2004 in SW Spain where gerbera plants showing wilt symptoms were observed in soilless crops. In all cases, the planting material originated from the Netherlands. Recently on the base of experimental trials F. oxysporum f. sp. chrysanthemi was recognized as the causal agent of wilts of gerbera both in Italy and in Spain. The aim of this experimental work was the evaluation of the resistance/susceptibility of available cultivars of chrysanthemum and gerbera to the Fusarium wilt. The pathogenicity of two isolates of Fusarium chrysanthemi obtained from infected gerbera (Gerbera jamesonii) and chrysanthemum (Chrysanthemum morifolium) plants was tested on several varieties both of gerbera and chrysanthemum in 2004-2006. In 2004 and 2005 respectively 54 and 30 cultivars of chrysanthemum and 57 and 55 of gerbera were tested, while in 2006 only 53 cultivars of gerbera were tested. The results showed that respectively in 2004 and 2005 67 and 33 % of chrysanthemum cultivars were highly resistant to F. chrysanthemi obtained from chrysanthemum while 57 and 53 % were highly resistant to strain isolated from gerbera. In 2004, 2005 and 2006 47, 65 and 75 % of gerbera cultivars were highly resistant to F. chrysanthemi obtained from chrysanthemum and 48, 56 and 72 % were highly resistant to the strain isolated from gerbera.

  20. Haplotype Diversity at Sub1 Locus and Allelic Distribution Among Rice Varieties of Tide and Flood Prone Areas of South-East Asia

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    A.S.M. Masuduzzaman

    2017-07-01

    Full Text Available Single nucleotide polymorphisms and restriction digestion-based haplotype variations among 160 flood prone rice varieties were analyzed with enzymes Alu I and Cac8 I to generate polymorphisms at Sub1A and Sub1C loci (conferring submergence tolerance, respectively. Haplotype associated with phenotype was used to study the haplotype variations at Sub1A and Sub1C loci and to determine their functional influence on submergence tolerance and stem elongation. Three patterns at Sub1A locus, Sub1A0 (null allele, Sub1A1 (does not cut and Sub1A2 (one SNP, and four patterns at Sub1C locus, Sub1C1, Sub1C2, Sub1C3 and Sub1C4, were generated. Both tolerant Sub1A1 and intolerant Sub1A2 had the same length, but the difference was presence of a restriction site in the Sub1A2, but absent at the Sub1A1. Further, two types of polymorphism were detected at the Sub1C, one included major length polymorphisms (165, 170 and 175 bp and the other was a single restriction site at different position. Eight haplotypes (different combinations of the two loci, A1C1, A1C2, A1C4, A2C2, A2C4, A0C2, A0C3 and A0C4, were detected among 160 varieties. Haplotype A1C1 was comparatively more related to haplotypes A1C2 and A1C4, having the same Sub1A allele, and these haplotypes were found only in Bangladeshi, Sri Lankan and Indian varieties. Most tolerant varieties in A1C1 haplotype showed slow elongation, having tolerant specific Sub1A1 and Sub1C1 alleles. Further, the varieties Madabaru and Kottamali (A2C2 also showed moderate level of tolerance without Sub1A1 allele. These varieties were different with FR13A and also suspected to carry different novel tolerant genes at other loci. These materials could be used for hybridization with Sub1 varieties for pyramiding additional tolerant specific alleles into a single genotype for improving submergence tolerance in rice.

  1. Over-expression in the nucleotide-binding site-leucine rich repeat gene DEPG1 increases susceptibility to bacterial leaf streak disease in transgenic rice plants.

    Science.gov (United States)

    Guo, Lijia; Li, Min; Wang, Wujing; Wang, Lijuan; Hao, Guojing; Guo, Chiming; Chen, Liang

    2012-04-01

    Bacterial leaf streak of rice (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) is a widely-spread disease in the main rice-producing areas of the world. Investigating the genes that play roles in rice-Xoc interactions helps us to understand the defense signaling pathway in rice. Here we report a differentially expressed protein gene (DEPG1), which regulates susceptibility to BLS. DEPG1 is a nucleotide-binding site (NBS)-leucine rich repeat (LRR) gene, and the deduced protein sequence of DEPG1 has approximately 64% identity with that of the disease resistance gene Pi37. Phylogenetic analysis of DEPG1 and the 18 characterized NBS-LRR genes revealed that DEPG1 is more closely related to Pi37. DEPG1 protein is located to the cytoplasm, which was confirmed by transient expression of DEPG1-GFP (green fluorescent protein) fusion construct in onion epidermal cells. Semi-quantitative PCR assays showed that DEPG1 is widely expressed in rice, and is preferentially expressed in internodes, leaf blades, leaf sheaths and flag leaves. Observation of cross sections of leaves from the transgenic plants with a DEPG1-promoter::glucuronidase (GUS) fusion gene revealed that DEPG1 is also highly expressed in mesophyll tissues where Xoc mainly colonizes. Additionally, Xoc negatively regulates expression of DEPG1 at the early stage of the pathogen infection, and so do the three defense-signal compounds including salicylic acid (SA), methyl jasmonate (MeJA) and 1-aminocyclopropane-1-carboxylic-acid (ACC). Transgenic rice plants overexpressing DEPG1 exhibit enhanced susceptibility to Xoc compared to the wild-type controls. Moreover, enhanced susceptibility to Xoc may be mediated by inhibition of the expression of some SA biosynthesis-related genes and pathogenesis-related genes that may contribute to the disease resistance. Taken together, DEPG1 plays roles in the interactions between rice and BLS pathogen Xoc.

  2. Cloning and Sequence Analysis of the Amylase Gene from the Rice Pest Walker and its Inhibitor from Wheat (Variety MP Sehore

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    Poonam Sharma

    2009-01-01

    Full Text Available Scirpophaga incertulas Walker (Lepidoptera: Pyralideae, commonly known as yellow stem borer, is a predominant monophagous pest of rice, which causes 5% to 30% loss of the rice crop. We report for the first time, the cloning and sequence analysis of the amylase gene of this pest. The cloned gene translates into a protein of 487 amino acids having a predicted molecular weight of 54,955 daltons and a theoretical pI of 5.9. The 3D structure of the amylase is predicted from its amino acid sequence by homology modeling using the structure of the amylase from Tenebrio molitor L (Coleoptera: Tenebrionidae. We also report the purification of a dimeric α-amylase inhibitor from a local variety of wheat MP Sehore that is specific for the amylase of this pest and does not inhibit human salivary amylase or porcine pancreatic amylase. The gene encoding this inhibitor has been cloned and its sequence has been analysed to find a possible explanation for this specificity.

  3. Contrasting effects of elevated CO{sub 2} on Cu and Cd uptake by different rice varieties grown on contaminated soils with two levels of metals: Implication for phytoextraction and food safety

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhongyang [Centre for Research in Ecotoxicology and Environmental Remediation, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191 (China); Open Key Laboratory of Agro-environment and Agro-product Safety of Ministry of Agriculture, Tianjin (China); Tang Shirong, E-mail: tangshir@hotmail.com [Centre for Research in Ecotoxicology and Environmental Remediation, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191 (China); Open Key Laboratory of Agro-environment and Agro-product Safety of Ministry of Agriculture, Tianjin (China); Deng Xiaofang; Wang Ruigang; Song Zhengguo [Centre for Research in Ecotoxicology and Environmental Remediation, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191 (China); Open Key Laboratory of Agro-environment and Agro-product Safety of Ministry of Agriculture, Tianjin (China)

    2010-05-15

    A pot experiment in six open-top chambers with two levels of CO{sub 2} and two multi-metal contaminated soils was conducted to investigate combined effects of elevated CO{sub 2} levels and metals (Cu and Cd) on rice. Elevated CO{sub 2} significantly increased the total dry weight biomass of six Chinese rice by 20-108 and 32-142% for low and high levels of contaminated soils, respectively. We observed dilution/little varied phenomena in grain Cu concentration in six rice varieties grown on both contaminated soils under elevated CO{sub 2}. We found significantly higher Cd concentrations in the parts of three rice varieties under elevated CO{sub 2}, but lower levels for the others. Two major conclusions can be drawn from our study: (1) rice varieties with significantly increased biomass and metal uptake under elevated CO{sub 2} exhibit greater potential for phytoextraction and (2) given expected global increases in CO{sub 2} concentration, CO{sub 2}-induced accumulation of metals in rice might be a component contributing to the potential health risk in the future, with Cd being a more important threat to human health than Cu.

  4. Rice brown spot and susceptibility of some cultivars in north of Iran.

    Science.gov (United States)

    Safari-Motlagh, M R; Hedjaroude, Gh A; Zad, S J; Okhovvat, S M

    2002-01-01

    Rice brown spot is one of the important diseases in the world including Iran. 91 samples of the infected plants such as leaves and panicles were collected from different locations of Guilan province, North of Iran and the fungi isolated and studied for pathogenicity. Three species of Bipolaris (B. oryzae, Bipolaris sp. and B. cf. victoriae) were isolated more than other species with serious effects on the plants respectively. Reactions of 8 cultivars of rice, Neda, Nemat, Sepeed-rood, Bejar, Khazar, Domsephid, Hassan-saraee and Binam were studied in greenhouse to Bipolaris sp. and B. cf. victoriae in two stages of growth, on leaves and panicles, respectively. The results showed that in seedling stage on leaf there was no significant difference between these cultivars in case of infection rates. In heading stage, although there was no significant difference according to variance analysis, but according to Duncan test (5%) they could be divided into 3 groups. Neda, Sepeed-rood, Khazar and Binam, with the lowest infection rate, were in the first group Bejar, Domsephid and Hassan-saraee were classified into the second group and Nemat was in the third one. Curvularia sp., Nigrospora sp., Pyricularia grisea and Alternaria sp. were with minor prevalence in infection of the plants.

  5. Nutritive value of straw, with special reference to wet-season rice straw as related to variety and location of growth in East-Java, Indonesia.

    NARCIS (Netherlands)

    Soebarinoto,; Siti Chuzaemi,; Hermanto,; Hartutik,; Bruchem, van J.; Orskov, E.R.

    1993-01-01

    Variation in nutritive quality between morphological components is less for rice straw than for wheat straw. Wheat straw stems have a lower quality than stems of rice straw, while leaves and leaf sheaths of wheat are of better quality than of rice. Variation in voluntary organic matter intake, and

  6. Proteomic Analysis of Copper-Binding Proteins in Excess Copper-Stressed Roots of Two Rice (Oryza sativa L. Varieties with Different Cu Tolerances.

    Directory of Open Access Journals (Sweden)

    Chen Chen

    Full Text Available To better understand the mechanisms involved in the heavy metal stress response and tolerance in plants, a proteomic approach was used to investigate the differences in Cu-binding protein expression in Cu-tolerant and Cu-sensitive rice varieties. Cu-binding proteins from Cu-treated rice roots were separated using a new IMAC method in which an IDA-sepharose column was applied prior to the Cu-IMAC column to remove metal ions from protein samples. More than 300 protein spots were reproducibly detected in the 2D gel. Thirty-five protein spots exhibited changes greater than 1.5-fold in intensity compared to the control. Twenty-four proteins contained one or more of nine putative metal-binding motifs reported by Smith et al., and 19 proteins (spots contained one to three of the top six motifs reported by Kung et al. The intensities of seven protein spots were increased in the Cu-tolerant variety B1139 compared to the Cu-sensitive variety B1195 (p<0.05 and six protein spots were markedly up-regulated in B1139, but not detectable in B1195. Four protein spots were significantly up-regulated in B1139, but unchanged in B1195 under Cu stress. In contrast, two protein spots were significantly down-regulated in B1195, but unchanged in B1139. These Cu-responsive proteins included those involved in antioxidant defense and detoxification (spots 5, 16, 21, 22, 28, 29 and 33, pathogenesis (spots 5, 16, 21, 22, 28, 29 and 33, regulation of gene transcription (spots 8 and 34, amino acid synthesis (spots 8 and 34, protein synthesis, modification, transport and degradation (spots 1, 2, 4, 10, 15, 19, 30, 31, 32 and 35, cell wall synthesis (spot 14, molecular signaling (spot 3, and salt stress (spots 7, 9 and 27; together with other proteins, such as a putative glyoxylate induced protein, proteins containing dimeric alpha-beta barrel domains, and adenosine kinase-like proteins. Our results suggest that these proteins, together with related physiological processes, play

  7. Proteomic Analysis of Copper-Binding Proteins in Excess Copper-Stressed Roots of Two Rice (Oryza sativa L.) Varieties with Different Cu Tolerances.

    Science.gov (United States)

    Chen, Chen; Song, Yufeng; Zhuang, Kai; Li, Lu; Xia, Yan; Shen, Zhenguo

    2015-01-01

    To better understand the mechanisms involved in the heavy metal stress response and tolerance in plants, a proteomic approach was used to investigate the differences in Cu-binding protein expression in Cu-tolerant and Cu-sensitive rice varieties. Cu-binding proteins from Cu-treated rice roots were separated using a new IMAC method in which an IDA-sepharose column was applied prior to the Cu-IMAC column to remove metal ions from protein samples. More than 300 protein spots were reproducibly detected in the 2D gel. Thirty-five protein spots exhibited changes greater than 1.5-fold in intensity compared to the control. Twenty-four proteins contained one or more of nine putative metal-binding motifs reported by Smith et al., and 19 proteins (spots) contained one to three of the top six motifs reported by Kung et al. The intensities of seven protein spots were increased in the Cu-tolerant variety B1139 compared to the Cu-sensitive variety B1195 (pprotein spots were markedly up-regulated in B1139, but not detectable in B1195. Four protein spots were significantly up-regulated in B1139, but unchanged in B1195 under Cu stress. In contrast, two protein spots were significantly down-regulated in B1195, but unchanged in B1139. These Cu-responsive proteins included those involved in antioxidant defense and detoxification (spots 5, 16, 21, 22, 28, 29 and 33), pathogenesis (spots 5, 16, 21, 22, 28, 29 and 33), regulation of gene transcription (spots 8 and 34), amino acid synthesis (spots 8 and 34), protein synthesis, modification, transport and degradation (spots 1, 2, 4, 10, 15, 19, 30, 31, 32 and 35), cell wall synthesis (spot 14), molecular signaling (spot 3), and salt stress (spots 7, 9 and 27); together with other proteins, such as a putative glyoxylate induced protein, proteins containing dimeric alpha-beta barrel domains, and adenosine kinase-like proteins. Our results suggest that these proteins, together with related physiological processes, play an important role in the

  8. Expression of Orseolia oryzae nucleoside diphosphate kinase (OoNDPK) is enhanced in rice gall midge feeding on susceptible rice hosts and its over-expression leads to salt tolerance in Escherichia coli.

    Science.gov (United States)

    Sinha, D K; Atray, I; Bentur, J S; Nair, S

    2012-12-01

    The Asian rice gall midge, Orseolia oryzae, is a major dipteran pest of rice, with many known biotypes. The present investigation was initiated to understand the molecular mechanisms of infestation for developing novel integrated pest management strategies. We isolated and characterized a gene, nucleoside diphosphate kinase (OoNDPK), from the rice gall midge, encoding a protein with 169 amino acid residues and with a secretory signal sequence - an observation that assumes significance as salivary gland secretions have been implicated to play a major role in insect-plant interactions. Furthermore, up-regulation (> 18 folds) of OoNDPK was observed in the salivary glands of maggots feeding on susceptible host in contrast to those feeding on resistant host. Phylogenetic analysis revealed similarity of OoNDPK with its dipteran orthologues. 3DLigandSite analysis, of the predicted OoNDPK and its orthologues, revealed phenylalanine and tyrosine residues to be specifically present in NDPK proteins from the plant feeders. Results suggest secretion of OoNDPK into the host plant and its probable involvement in gall midge-rice interaction. Using the coleoptile cell elongation assay, we demonstrated that the recombinant OoNDPK is capable of causing elongation of rice coleoptile cells. Additionally, heterologous expression of OoNDPK in Escherichia coli increased the tolerance of these cells to salt (NaCl; up to 1 mM), hinting at the involvement of this gene in abiotic stress response as well. © 2012 Royal Entomological Society.

  9. Dynamic metabolic responses of brown planthoppers towards susceptible and resistant rice plants

    OpenAIRE

    Liu, Caixiang; Du, Ba; Hao, Fuhua; Lei, Hehua; Wan, Qianfen; He, Guangcun; Wang, Yulan; Tang, Huiru

    2017-01-01

    Summary Brown planthopper (Nilaparvata lugens Stål, BPH) causes huge economic losses in rice‐growing regions, and new strategies for combating BPH are required. To understand how BPHs respond towards BPH‐resistant plants, we systematically analysed the metabolic differences between BPHs feeding on the resistant and susceptible plants using NMR and GC‐FID/MS. We also measured the expression of some related genes involving glycolysis and biosyntheses of trehalose, amino acids, chitin and fatty ...

  10. Genome-wide DNA polymorphism in the indica rice varieties RGD-7S and Taifeng B as revealed by whole genome re-sequencing.

    Science.gov (United States)

    Fu, Chong-Yun; Liu, Wu-Ge; Liu, Di-Lin; Li, Ji-Hua; Zhu, Man-Shan; Liao, Yi-Long; Liu, Zhen-Rong; Zeng, Xue-Qin; Wang, Feng

    2016-03-01

    Next-generation sequencing technologies provide opportunities to further understand genetic variation, even within closely related cultivars. We performed whole genome resequencing of two elite indica rice varieties, RGD-7S and Taifeng B, whose F1 progeny showed hybrid weakness and hybrid vigor when grown in the early- and late-cropping seasons, respectively. Approximately 150 million 100-bp pair-end reads were generated, which covered ∼86% of the rice (Oryza sativa L. japonica 'Nipponbare') reference genome. A total of 2,758,740 polymorphic sites including 2,408,845 SNPs and 349,895 InDels were detected in RGD-7S and Taifeng B, respectively. Applying stringent parameters, we identified 961,791 SNPs and 46,640 InDels between RGD-7S and Taifeng B (RGD-7S/Taifeng B). The density of DNA polymorphisms was 256.8 SNPs and 12.5 InDels per 100 kb for RGD-7S/Taifeng B. Copy number variations (CNVs) were also investigated. In RGD-7S, 1989 of 2727 CNVs were overlapped in 218 genes, and 1231 of 2010 CNVs were annotated in 175 genes in Taifeng B. In addition, we verified a subset of InDels in the interval of hybrid weakness genes, Hw3 and Hw4, and obtained some polymorphic InDel markers, which will provide a sound foundation for cloning hybrid weakness genes. Analysis of genomic variations will also contribute to understanding the genetic basis of hybrid weakness and heterosis.

  11. An efficient and reproducible method for regeneration of whole plants from mature seeds of a high yielding Indica rice (Oryza sativa L.) variety PAU 201.

    Science.gov (United States)

    Wani, Shabir H; Sanghera, Gulzar S; Gosal, Satbir S

    2011-07-01

    Tissue culture is one of the tools necessary for genetic engineering and many other breeding programs. Moreover, selection of high regenerating rice varieties is a pre-requisite for success in rice biotechnology. In this report we established a reproducible plant regeneration system through somatic embryogenesis. The explants used for regeneration were embryogenic calli derived from mature seeds cultured on callus induction media. For callus induction mature seeds were cultured on MS medium containing 30 g/l sucrose combined with 560 mg/l proline and 1.5-3.5 mg/l 2,4-D and 0.5-1.5 mg/l Kin. For plant regeneration, embryogenic calli were transferred to MS medium containing 30 g/l sucrose, supplemented with 1.0-3.0 mg/l BAP, 0.5-1.5 mg/l Kin and 0.5-1.5 mg/l NAA. The highest frequency of callus induction (44.4%) was observed on the MS medium supplemented with 2.5 mg/l 2,4-D, 0.5 mg/l Kin, 560 mg/l proline and 30 g/l sucrose. The highest frequency of shoot regeneration (42.5%) was observed on the MS medium supplemented with 2.0 mg/l BAP, 0.5 mg/l NAA and 0.5 mg/l Kin. The plantlets were hardened and transferred to soil in earthen pots. The developed method was highly reproducible. The in vitro developed plants showed normal growth and flowering under glasshouse conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Salt Tolerance in Rice: Focus on Mechanisms and Approaches

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    Inja Naga Bheema Lingeswara Reddy

    2017-05-01

    Full Text Available Salt tolerance is an important constrain for rice, which is generally categorized as a typical glycophyte. Soil salinity is one of the major constraints affecting rice production worldwide, especially in the coastal areas. Susceptibility or tolerance of rice plants to high salinity is a coordinated action of multiple stress responsive genes, which also interacts with other components of stress signal transduction pathways. Salt tolerant varieties can be produced by marker-assisted selection or genetic engineering by introducing salt-tolerance genes. In this review, we have updated on mechanisms and genes which can help in transferring of the salt tolerance into high-yielding rice varieties. We have focused on the need for integrating phenotyping, genomics, metabolic profiling and phenomics into transgenic and breeding approaches to develop high-yielding as well as salt tolerant rice varieties.

  13. Bran data of total flavonoid and total phenolic contents, oxygen radical absorbance capacity, and profiles of proanthocyanidins and whole grain physical traits of 32 red and purple rice varieties

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    Ming-Hsuan Chen

    2016-09-01

    Full Text Available Phytochemicals in red and purple bran rice have potential health benefit to humans. We determined the phytochemicals in brans of 32 red and purple global rice varieties. The description of the origin and physical traits of the whole grain (color, length, width, thickness and 100-kernel weight of this germplasm collection are provided along with data of total flavonoid and total phenolic contents, oxygen radical absorbance capacity and total proanthocyanidin contents. The contents and proportions of individual oligomers, from degree of polymerization of monomers to 14-mers, and polymers in bran of these 32 rice varieties are presented (DOI: http://dx.doi.org/10.1016/j.foodchem.2016.04.004 [1].

  14. Determination of contents and antioxidant activity of free and bound phenolics compounds and in vitro digestibility of commercial black and red rice (Oryza sativa L.) varieties.

    Science.gov (United States)

    Sumczynski, Daniela; Kotásková, Eva; Družbíková, Helena; Mlček, Jiří

    2016-11-15

    Black and red rices (Oryza sativa L.) were analysed for total flavonoids and phenolics and the HPLC profile including both free and bound phenolic fractions. Moreover, antioxidant activity and in vitro digestibility was determined. Content of flavonoids and polyphenols as well as antioxidant activity was higher in free phenolic fractions. Bound flavonoids in black rices were not significant contributors to antioxidant activity. The main free phenolics in black rices were ferulic, protocatechuic and trans-p-coumaric acids, while the major free phenolics in red rices were catechin, protocatechuic and caffeic acids. The main bound phenolics in black rices were ferulic and vanillic acids and quercetin, in red rice types, they were ferulic, syringic, trans-p-coumaric acids and quercetin. Newly, the presence of m-coumaric acid in red rices was detected. Steam cooked rices showed very high levels of organic matter digestibility, whereas red rices were significantly more digestible than black rices (p<0.05). Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Prevalence and antimicrobial susceptibility of Salmonella isolated from a variety of raw meat sausages in Gaborone (Botswana) retail stores.

    Science.gov (United States)

    Samaxa, Ronald Gaelekolwe; Matsheka, Maitshwarelo Ignatius; Mpoloka, Sununguko Wata; Gashe, Berhanu Abegaz

    2012-04-01

    The objective of the study was to provide baseline data on the prevalence and antimicrobial susceptibility of Salmonella in different types of raw meat sausages directly accessible to the consumers in Gaborone, Botswana. A total of 300 raw sausages comprising 79 beef, 78 pork, 72 chicken, and 71 mutton samples were concurrently analyzed for the presence of Salmonella using a conventional culture method and a validated PCR method. The PCR assay results were in full concordance with those of the conventional culture method for the detection of Salmonella. Sixty-five (21.7%) of 300 samples were positive for Salmonella by both the conventional culture method and PCR assay. Even though more chicken samples contained Salmonella than did any other sausage type, the difference in the presence of Salmonella among the four sausages types was not significant. Eleven serotypes were identified, and Salmonella enterica subsp. salamae II was most prevalent in all the sausage types. Beef sausages generally had higher mesophilic bacterial counts than did the other three sausage types. However, higher microbial counts were not reflective of the presence of salmonellae. Susceptibility of the Salmonella enterica serotypes to 20 antimicrobial agents was determined, and Salmonella Muenchen was resistant to the widest array of agents and was mostly isolated from chicken sausages. Regardless of the meat of origin, all 65 Salmonella isolates were resistant to at least four antimicrobial agents: amikacin, gentamicin, cefuroxime, and tombramycin. This resistance profile group was the most common in all four sausage types, comprising 90% of all Salmonella isolates from beef, 71% from pork, 63% from mutton, and 35% from chicken. These results suggest that raw sausages pose a risk of transmitting multidrug-resistant Salmonella isolates to consumers.

  16. Effects of salt and low light intensity during the vegetative stage on susceptibility of rice to male sterility induced by chilling stress during the reproductive stage

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    Takemasa Koumoto

    2016-10-01

    Full Text Available We tested whether exposing rice plants to abiotic stress (salt or shade during vegetative growth affects the chilling tolerance of reproductive organs, which is one of the most important traits for rice growing in a cool climate; we used two rice cultivars with different tolerance in two growing seasons. We divided the vegetative growth into three phases to clarify the most sensitive period: 7–22 days after transplanting (DAT, 23–38 DAT and 39–54 DAT. Chilling tolerance of the pre-stressed plants was based on the male sterility induced by low temperatures. Shade and salt stress during all three vegetative growth phases significantly reduced stomatal conductance. Shade decreased the specific leaf weight and the leaf sugar and starch contents, but salt had no significant effect, despite causing leaf damage. Low temperatures during the reproductive stage induced spikelet sterility in all plants, but the magnitude was greater in the salt- and shade-stressed plants of both cultivars, especially those stressed late during vegetative growth. The increased spikelet sterility caused by chilling was closely related to the reduction of the total spikelet number per panicle. This is the first study to show that salt and low light stress during vegetative growth increased the susceptibility of rice plants to chilling damage during panicle development.

  17. Expression of the maize ZmGF14-6 gene in rice confers tolerance to drought stress while enhancing susceptibility to pathogen infection

    Science.gov (United States)

    Campo, Sonia; Peris-Peris, Cristina; Montesinos, Laura; Peñas, Gisela; Messeguer, Joaquima; San Segundo, Blanca

    2012-01-01

    14-3-3 proteins are found in all eukaryotes where they act as regulators of diverse signalling pathways associated with a wide range of biological processes. In this study the functional characterization of the ZmGF14-6 gene encoding a maize 14-3-3 protein is reported. Gene expression analyses indicated that ZmGF14-6 is up-regulated by fungal infection and salt treatment in maize plants, whereas its expression is down-regulated by drought stress. It is reported that rice plants constitutively expressing ZmGF14-6 displayed enhanced tolerance to drought stress which was accompanied by a stronger induction of drought-associated rice genes. However, rice plants expressing ZmGF14-6 either in a constitutive or under a pathogen-inducible regime showed a higher susceptibility to infection by the fungal pathogens Fusarium verticillioides and Magnaporthe oryzae. Under infection conditions, a lower intensity in the expression of defence-related genes occurred in ZmGF14-6 rice plants. These findings support that ZmGF14-6 positively regulates drought tolerance in transgenic rice while negatively modulating the plant defence response to pathogen infection. Transient expression assays of fluorescently labelled ZmGF14-6 protein in onion epidermal cells revealed a widespread distribution of ZmGF14-6 in the cytoplasm and nucleus. Additionally, colocalization experiments of fluorescently labelled ZmGF14-6 with organelle markers, in combination with cell labelling with the endocytic tracer FM4-64, revealed a subcellular localization of ZmGF14-6 in the early endosomes. Taken together, these results improve our understanding of the role of ZmGF14-6 in stress signalling pathways, while indicating that ZmGF14-6 inversely regulates the plant response to biotic and abiotic stresses. PMID:22016430

  18. The transcriptional response to the olive fruit fly (Bactrocera oleae) reveals extended differences between tolerant and susceptible olive (Olea europaea L.) varieties.

    Science.gov (United States)

    Grasso, Filomena; Coppola, Mariangela; Carbone, Fabrizio; Baldoni, Luciana; Alagna, Fiammetta; Perrotta, Gaetano; Pérez-Pulido, Antonio J; Garonna, Antonio; Facella, Paolo; Daddiego, Loretta; Lopez, Loredana; Vitiello, Alessia; Rao, Rosa; Corrado, Giandomenico

    2017-01-01

    The olive fruit fly Bactrocera oleae (Diptera: Tephritidae) is the most devastating pest of cultivated olive (Olea europaea L.). Intraspecific variation in plant resistance to B. oleae has been described only at phenotypic level. In this work, we used a transcriptomic approach to study the molecular response to the olive fruit fly in two olive cultivars with contrasting level of susceptibility. Using next-generation pyrosequencing, we first generated a catalogue of more than 80,000 sequences expressed in drupes from approximately 700k reads. The assembled sequences were used to develop a microarray layout with over 60,000 olive-specific probes. The differential gene expression analysis between infested (i.e. with II or III instar larvae) and control drupes indicated a significant intraspecific variation between the more tolerant and susceptible cultivar. Around 2500 genes were differentially regulated in infested drupes of the tolerant variety. The GO annotation of the differentially expressed genes implies that the inducible resistance to the olive fruit fly involves a number of biological functions, cellular processes and metabolic pathways, including those with a known role in defence, oxidative stress responses, cellular structure, hormone signalling, and primary and secondary metabolism. The difference in the induced transcriptional changes between the cultivars suggests a strong genetic role in the olive inducible defence, which can ultimately lead to the discovery of factors associated with a higher level of tolerance to B. oleae.

  19. Suscetibilidade de biótipos de arroz-vermelho e de cultivares de arroz irrigado ao herbicida imazethapyr Susceptibility of red rice biotypes and commercial rice cultivars to imazethapyr

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    S.H.B. Dornelles

    2010-01-01

    Full Text Available Para avaliar a suscetibilidade de biótipos de arroz-vermelho(Oryza sativa e cultivares comerciais de arroz ao herbicida imazethapyr, realizou-se um ensaio em casa de vegetação com cinco biótipos de arroz-vermelho (acessos Santa Maria 5, Pelotas 3, Rio Pardo 1, Manoel Viana 2 e Catuçaba 1, dois cultivares comerciais de arroz: Clearfield® (IRGA 422 CL e Puitá INTA CL e um cultivar convencional (IRGA 417. Utilizou-se a metodologia de curvas de dose-resposta proposta por Seefeldt et al. (1995. A metodologia de curvas de resposta foi gerada a partir dos parâmetros do modelo logístico e dos valores de I50. Os biótipos de arroz-vermelho e os cultivares foram submetidos a seis doses do herbicida imazethapyr (0; 33,12; 66,25; 132,5; 265,0; e 530,0 g i.a. ha-1. As plantas de arroz foram contadas e coletadas no 20º dia após a aplicação dos tratamentos. A análise do percentual de dano foi realizada através de avaliação visual da fitointoxicação (%, massa verde e massa seca das plantas. Analisando as curvas e os resultados da análise da variância, pode-se inferir que os cultivares Clearfield Irga 422 CL e Puitá INTA CL foram significativamente iguais ao biótipo de arroz-vermelho Catuçaba 1, resistindo a doses de imazethapyr superiores à recomendada em campo para o sistema Clearfield®. Os biótipos Manoel Viana 2, Santa Maria 5 e Pelotas 3 agruparam-se com o cultivar convencional IRGA 417, sendo suscetíveis à dose comercial do herbicida. O biótipo Rio Pardo 1 também é resistente ao herbicida imazethapyr, porém menos resistente que o biótipo Catuçaba 1.To evaluate the susceptibility of biotypes of red rice (Oryza sativa and commercial rice cultivars to the herbicide imazethapyr, a greenhouse assay was conducted with five red rice biotypes (accesses Santa Maria 5, Pelotas 3, Rio Pardo 1, 2 and Manoel Viana Catuçaba 1, two commercial rice cultivars: Clearfield ® (Irga CL 422 and CL Puit INTA, and a conventional cultivar (Irga

  20. Exogenous proline and glycine betaine mediated upregulation of antioxidant defense and glyoxalase systems provides better protection against salt-induced oxidative stress in two rice (Oryza sativa L.) varieties.

    Science.gov (United States)

    Hasanuzzaman, Mirza; Alam, Md Mahabub; Rahman, Anisur; Hasanuzzaman, Md; Nahar, Kamrun; Fujita, Masayuki

    2014-01-01

    The present study investigates the roles of exogenous proline (Pro, 5 mM) and glycine betaine (GB, 5 mM) in improving salt stress tolerance in salt sensitive (BRRI dhan49) and salt tolerant (BRRI dhan54) rice (Oryza sativa L.) varieties. Salt stresses (150 and 300 mM NaCl for 48 h) significantly reduced leaf relative water (RWC) and chlorophyll (chl) content and increased endogenous Pro and increased lipid peroxidation and H2O2 levels. Ascorbate (AsA), glutathione (GSH) and GSH/GSSG, ascorbate peroxidae (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), catalase (CAT), and glyoxalase I (Gly I) activities were reduced in sensitive variety and these were increased in tolerant variety due to salt stress. The glyoxalase II (Gly II), glutathione S-transferase (GST), and superoxide dismutase (SOD) activities were increased in both cultivars by salt stress. Exogenous Pro and GB application with salt stress improved physiological parameters and reduced oxidative damage in both cultivars where BRRI dhan54 showed better tolerance. The result suggests that exogenous application of Pro and GB increased rice seedlings' tolerance to salt-induced oxidative damage by upregulating their antioxidant defense system where these protectants rendered better performance to BRRI dhan54 and Pro can be considered as better protectant than GB.

  1. Exogenous Proline and Glycine Betaine Mediated Upregulation of Antioxidant Defense and Glyoxalase Systems Provides Better Protection against Salt-Induced Oxidative Stress in Two Rice (Oryza sativa L.) Varieties

    Science.gov (United States)

    Hasanuzzaman, Mirza; Alam, Md. Mahabub; Rahman, Anisur; Hasanuzzaman, Md.; Nahar, Kamrun; Fujita, Masayuki

    2014-01-01

    The present study investigates the roles of exogenous proline (Pro, 5 mM) and glycine betaine (GB, 5 mM) in improving salt stress tolerance in salt sensitive (BRRI dhan49) and salt tolerant (BRRI dhan54) rice (Oryza sativa L.) varieties. Salt stresses (150 and 300 mM NaCl for 48 h) significantly reduced leaf relative water (RWC) and chlorophyll (chl) content and increased endogenous Pro and increased lipid peroxidation and H2O2 levels. Ascorbate (AsA), glutathione (GSH) and GSH/GSSG, ascorbate peroxidae (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), catalase (CAT), and glyoxalase I (Gly I) activities were reduced in sensitive variety and these were increased in tolerant variety due to salt stress. The glyoxalase II (Gly II), glutathione S-transferase (GST), and superoxide dismutase (SOD) activities were increased in both cultivars by salt stress. Exogenous Pro and GB application with salt stress improved physiological parameters and reduced oxidative damage in both cultivars where BRRI dhan54 showed better tolerance. The result suggests that exogenous application of Pro and GB increased rice seedlings' tolerance to salt-induced oxidative damage by upregulating their antioxidant defense system where these protectants rendered better performance to BRRI dhan54 and Pro can be considered as better protectant than GB. PMID:24991566

  2. Exogenous Proline and Glycine Betaine Mediated Upregulation of Antioxidant Defense and Glyoxalase Systems Provides Better Protection against Salt-Induced Oxidative Stress in Two Rice (Oryza sativa L. Varieties

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    Mirza Hasanuzzaman

    2014-01-01

    Full Text Available The present study investigates the roles of exogenous proline (Pro, 5 mM and glycine betaine (GB, 5 mM in improving salt stress tolerance in salt sensitive (BRRI dhan49 and salt tolerant (BRRI dhan54 rice (Oryza sativa L. varieties. Salt stresses (150 and 300 mM NaCl for 48 h significantly reduced leaf relative water (RWC and chlorophyll (chl content and increased endogenous Pro and increased lipid peroxidation and H2O2 levels. Ascorbate (AsA, glutathione (GSH and GSH/GSSG, ascorbate peroxidae (APX, monodehydroascorbate reductase (MDHAR, dehydroascorbate reductase (DHAR, glutathione reductase (GR, glutathione peroxidase (GPX, catalase (CAT, and glyoxalase I (Gly I activities were reduced in sensitive variety and these were increased in tolerant variety due to salt stress. The glyoxalase II (Gly II, glutathione S-transferase (GST, and superoxide dismutase (SOD activities were increased in both cultivars by salt stress. Exogenous Pro and GB application with salt stress improved physiological parameters and reduced oxidative damage in both cultivars where BRRI dhan54 showed better tolerance. The result suggests that exogenous application of Pro and GB increased rice seedlings’ tolerance to salt-induced oxidative damage by upregulating their antioxidant defense system where these protectants rendered better performance to BRRI dhan54 and Pro can be considered as better protectant than GB.

  3. Effect of organic fertiliser residues from rice production on nitrogen fixation of soya (Glycine max L. Merrill, Chiang Mai 60 variety

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    Nattida Luangmaka

    2013-09-01

    Full Text Available A field study was undertaken on the residual effect of organic fertilisers applied to the preceding rice cropping on nitrogen fixation of soya in a rice-soya cropping system. The experiment was conducted on a farmer’s lowland paddy in Mae Rim district, Chiang Mai province, Thailand. Organic fertiliser treatments assigned were: 1 control (no fertiliser, 2 animal manure of cattle (AM, 3 compost (CP, 4 azolla (AZ, 5 AM + CP, 6 AM + AZ, 7 CP + AZ and 8 AM + CP + AZ. Soya seeds were planted without rhizobial inoculation in December 2011, four months after the application of organic fertilisers. Nodule weight, total shoot nitrogen accumulation and relative ureide index at various growth stages were recorded as the indices of nitrogen fixation. Results of the study demonstrate that the residues from the application the organic fertilisers of narrow C/N ratios during the land preparation for rice cropping four months before soya cultivation promoted nitrogen fixation by native rhizobia.

  4. Dynamical roguing model for controlling the spread of tungro virus via Nephotettix Virescens in a rice field

    Science.gov (United States)

    Blas, Nikki; David, Guido

    2017-10-01

    Rice tungro disease is described as a cancer due to its major impact on the livelihood of farmers and the difficulty of controlling it. Tungro is a semi-persistent virus transmitted by green leafhoppers called Nephotettix Virescens. In this paper, we presented a compartmental plant-vector model of the Nephotettix Virescens - rice plant interaction based on a system of ordinary differential equations to simulate the effects of roguing in controlling the spread of Tungro virus in a model rice field of susceptible rice variety (Taichung Native 1).

  5. Caracterização morfológica de cultivares de arroz visando a certificação da pureza varietal Morphological characteristics of rice cultivars; application for variety purity certification

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    Sandro Bonow

    2007-06-01

    Full Text Available Com o presente trabalho, objetivou-se avaliar a eficiência dos descritores morfológicos, na caracterização de cultivares comerciais de arroz (Oryza sativa L., servindo como suporte às empresas produtoras de sementes na identificação de cultivares, assim como às exigências da Lei de Proteção de Cultivares. Foram caracterizadas as cultivares de arroz Carisma, IAC 202, Confiança, Douradão, Guarani, Primavera, Canastra e Caiapó. O estudo consistiu de dois experimentos, o primeiro conduzido em casa-de-vegetação, quando os genótipos foram caracterizados utilizando-se dos descritores morfológicos recomendados para o registro e proteção de cultivares. O segundo experimento foi conduzido em uma área de produção de sementes e consistiu na identificação, por parte de avaliadores, de variedades de arroz contaminantes propositalmente distribuídas junto às cultivares em estudo. Concluiu-se que os descritores morfológicos são úteis, porém, não suficientes para a caracterização e diferenciação de cultivares de arroz. As características morfológicas observadas em sementes e plantas após a antese são as mais adequadas para a caracterização e diferenciação de cultivares. Os genótipos de arroz de sequeiro apresentam grande similaridade morfológica.This study had the objective of evaluating the efficiency of morphological markers as descriptors for commercial rice cultivars (Oryza sativa L. to be used in cultivar identification by seed companies, as well as, to fulfill the requirements for cultivar protection law. The studied cultivars were: Confiança, IAC 202, Carisma, Primavera, Guarani, Douradão, Canastra, and Caiapó. This study consisted of two experiments: one, conducted in greenhouse, where the varieties were characterized based on morphological descriptors recommended by protection cultivar law; the other, done in a seed production field that consisted in identification of rice contaminant varieties distributed

  6. Evaluation of the tolerance to Finale® in the germination and regeneration of Cuban rice varieties (IACuba-17 and IACuba-19

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    Daymí Abreu

    2005-01-01

    Full Text Available Selection agent used during the shoot selection has an important role on the transgenic plant generation efficiency. In this work, the tolerance to the herbicide Finale® in two Cuban rice cultivars, IACuba17 and IACuba-19 was evaluated, and determined that 10 days exposure to 5 and 10 mg.l-1 of Finale® were enough to avoid seedlings of IAC-17 and IAC-19, respectively. Cultivated calluses (0, 2, 4 and 6 days in the absence of Finale®in the regeneration medium were used to evaluate the minimal concentration of Finale®that totally inhibits shoot regeneration. Pre-induced calluses cultured during two days and 3 mg.l-1 of Finale® in the regeneration medium was the most efficient combination to select shoots during the generation of transgenic plants resistant to the herbicide. Our shoot selection procedure reduces to 3 weeks the time to obtain shoots during the generation of transgenic rice plants. Key words: germination, mature seeds, Oryza, phosphinothricin, regeneration, selection markers

  7. Reproductive stage physiological and transcriptional responses to salinity stress in reciprocal populations derived from tolerant (Horkuch) and susceptible (IR29) rice

    Science.gov (United States)

    Razzaque, Samsad; Haque, Taslima; Elias, Sabrina M.; Rahman, Md. Sazzadur; Biswas, Sudip; Schwartz, Scott; Ismail, Abdelbagi M.; Walia, Harkamal; Juenger, Thomas E.; Seraj, Zeba I.

    2017-04-01

    Global increase in salinity levels has made it imperative to identify novel sources of genetic variation for tolerance traits, especially in rice. The rice landrace Horkuch, endemic to the saline coastal area of Bangladesh, was used in this study as the source of tolerance in reciprocal crosses with the sensitive but high-yielding IR29 variety for discovering transcriptional variation associated with salt tolerance in the resulting populations. The cytoplasmic effect of the Horkuch background in leaves under stress showed functional enrichment for signal transduction, DNA-dependent regulation and transport activities. In roots the enrichment was for cell wall organization and macromolecule biosynthesis. In contrast, the cytoplasmic effect of IR29 showed upregulation of apoptosis and downregulation of phosphorylation across tissues relative to Horkuch. Differential gene expression in leaves of the sensitive population showed downregulation of GO processes like photosynthesis, ATP biosynthesis and ion transport. Roots of the tolerant plants conversely showed upregulation of GO terms like G-protein coupled receptor pathway, membrane potential and cation transport. Furthermore, genes involved in regulating membrane potentials were constitutively expressed only in the roots of tolerant individuals. Overall our work has developed genetic resources and elucidated the likely mechanisms associated with the tolerance response of the Horkuch genotype.

  8. Comparative analysis of root transcriptome profiles of two pairs of drought-tolerant and susceptible rice near-isogenic lines under different drought stress.

    Science.gov (United States)

    Moumeni, Ali; Satoh, Kouji; Kondoh, Hiroaki; Asano, Takayuki; Hosaka, Aeni; Venuprasad, Ramiah; Serraj, Rachid; Kumar, Arvind; Leung, Hei; Kikuchi, Shoshi

    2011-12-02

    Plant roots are important organs to uptake soil water and nutrients, perceiving and transducing of soil water deficit signals to shoot. The current knowledge of drought stress transcriptomes in rice are mostly relying on comparative studies of diverse genetic background under drought. A more reliable approach is to use near-isogenic lines (NILs) with a common genetic background but contrasting levels of resistance to drought stress under initial exposure to water deficit. Here, we examined two pairs of NILs in IR64 background with contrasting drought tolerance. We obtained gene expression profile in roots of rice NILs under different levels of drought stress help to identify genes and mechanisms involved in drought stress. Global gene expression analysis showed that about 55% of genes differentially expressed in roots of rice in response to drought stress treatments. The number of differentially expressed genes (DEGs) increased in NILs as the level of water deficits, increased from mild to severe condition, suggesting that more genes were affected by increasing drought stress. Gene onthology (GO) test and biological pathway analysis indicated that activated genes in the drought tolerant NILs IR77298-14-1-2-B-10 and IR77298-5-6-B-18 were mostly involved in secondary metabolism, amino acid metabolism, response to stimulus, defence response, transcription and signal transduction, and down-regulated genes were involved in photosynthesis and cell wall growth. We also observed gibberellic acid (GA) and auxin crosstalk modulating lateral root formation in the tolerant NILs. Transcriptome analysis on two pairs of NILs with a common genetic background (~97%) showed distinctive differences in gene expression profiles and could be effective to unravel genes involved in drought tolerance. In comparison with the moderately tolerant NIL IR77298-5-6-B-18 and other susceptible NILs, the tolerant NIL IR77298-14-1-2-B-10 showed a greater number of DEGs for cell growth, hormone

  9. Comparative analysis of root transcriptome profiles of two pairs of drought-tolerant and susceptible rice near-isogenic lines under different drought stress

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    Moumeni Ali

    2011-12-01

    Full Text Available Abstract Background Plant roots are important organs to uptake soil water and nutrients, perceiving and transducing of soil water deficit signals to shoot. The current knowledge of drought stress transcriptomes in rice are mostly relying on comparative studies of diverse genetic background under drought. A more reliable approach is to use near-isogenic lines (NILs with a common genetic background but contrasting levels of resistance to drought stress under initial exposure to water deficit. Here, we examined two pairs of NILs in IR64 background with contrasting drought tolerance. We obtained gene expression profile in roots of rice NILs under different levels of drought stress help to identify genes and mechanisms involved in drought stress. Results Global gene expression analysis showed that about 55% of genes differentially expressed in roots of rice in response to drought stress treatments. The number of differentially expressed genes (DEGs increased in NILs as the level of water deficits, increased from mild to severe condition, suggesting that more genes were affected by increasing drought stress. Gene onthology (GO test and biological pathway analysis indicated that activated genes in the drought tolerant NILs IR77298-14-1-2-B-10 and IR77298-5-6-B-18 were mostly involved in secondary metabolism, amino acid metabolism, response to stimulus, defence response, transcription and signal transduction, and down-regulated genes were involved in photosynthesis and cell wall growth. We also observed gibberellic acid (GA and auxin crosstalk modulating lateral root formation in the tolerant NILs. Conclusions Transcriptome analysis on two pairs of NILs with a common genetic background (~97% showed distinctive differences in gene expression profiles and could be effective to unravel genes involved in drought tolerance. In comparison with the moderately tolerant NIL IR77298-5-6-B-18 and other susceptible NILs, the tolerant NIL IR77298-14-1-2-B-10 showed

  10. Susceptibility of Different Populations of Nilaparvata lugens from Major Rice Growing Areas of Karnataka, India to Different Groups of Insecticides

    Directory of Open Access Journals (Sweden)

    Y.S. BASANTH

    2013-09-01

    Full Text Available Susceptibility to insecticides was investigated by collecting field populations of brown planthopper from different locations of southern Karnataka, India (Gangavati, Kathalagere, Kollegala, Soraba and Mandya. All the field populations differed in their susceptibility to insecticides. In general, Soraba and Mandya populations were more susceptible to insecticides compared to Gangavati and Kathalagere populations. The resistance ratios varied greatly among the populations viz., chlorpyriphos (1.13- to 16.82-fold, imidacloprid (0.53- to 13.50-fold, acephate (1.34- to 5.32-fold, fipronil (1.13- to 4.06-fold, thiamethoxam (1.01- to 2.19-fold, clothianidin (1.92- to 4.86-fold, dinotefuran (0.82- to 2.22-fold, buprofezin (1.06- to 5.43-fold and carbofuran (0.41- to 2.17-fold. The populations from Gangavati, Kathalagere and Kollegala exhibited higher resistance to some of the old insecticides and low resistance to new molecules.

  11. [In vitro susceptibility of Trichoconiella padwickii to various active ingredients used as fungicides in the cultivation of rice].

    Science.gov (United States)

    Lovato Echeverria, Alfonso D; Gutiérrez, Susana A; Carmona, Marcelo A

    The aim of this study was to evaluate in vitro the mycelial susceptibility of Trichoconiella padwickii to different active ingredients through average median concentration IC50 calculation. Inoculum disks were seeded on bean agar at different concentrations (0.1; 1; 10; 30, 50; 100 and 1000mg/l) of various fungicides. After seven days the colony diameter was measured. The data obtained were fitted to nonlinear regression models. Susceptibility was classified using the scale proposed by Edgington. The results show that the pathogen is very sensitive to products that act on the respiratory chain (quinone outside inhibitors [QoI] and succinate dehydrogenase inhibitors [SDHI]) and cell membrane (multi-site contact activity), and moderately sensitive to those products interfering with cell division (methyl benzimidazole carbamates [MBC]), synthesis of nucleic acids (phenylamides [PA]) and osmotic signal transduction (multi-site contact activity). This work is the first record on the sensitivity of T. padwickii. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Variability in contents of thiamine and riboflavin in brown rice, crude oil in brown rice and bran-polish, and silicon in hull of IR rices.

    Science.gov (United States)

    Villareal, C P; Juliano, B O

    1989-09-01

    Among 30 IR varieties, variety had greater effect on thiamine content of brown rice than season. Both season and variety affected riboflavin content. Purple- and red-pericarped Philippines rices had higher riboflavin and crude protein contents than IR rices. Crude oil contents of brown rice and bran-polish of 19 IR rices were significantly affected by variety, but only brown rice oil content was significantly affected by season. Bran-polish of waxy rice IR29 had the highest oil content. Silicon content of hull of 16 IR rices showed significant variation due to variety and season and tended to be higher in the dry season crop. Variety rankings in nutrient composition were not consistent for the two crops. The levels of nutrients of IR rices were within the range of values reported for other rices.

  13. Períodos de interferência das plantas daninhas na cultura do arroz de terras altas. II - cultivar Caiapó Interference periods of weeds in the upland rice - Caiapó variety

    Directory of Open Access Journals (Sweden)

    Maria Rosangela Malheiros Silva

    2009-01-01

    Full Text Available Os experimentos foram desenvolvidos nos anos agrícolas 2003/2004 e 2004/2005, em área experimental da Universidade Estadual Paulista, Campus de Jaboticabal (SP, com o objetivo de se determinarem os períodos de interferência das plantas daninhas na cultura do arroz de terras altas, cultivar Caiapó. O delineamento experimental foi em blocos ao acaso com quatro repetições e 16 tratamentos. Os tratamentos foram constituídos por períodos crescentes de controle ou de convivência das plantas daninhas após a emergência da cultura: 0-10, 0-20, 0-30, 0-40, 0-50, 0-60, 0-70 dias e 0-colheita. Nos dois anos, as famílias predominantes eram Poaceae, Asteraceae, Amaranthaceae e Malvaceae e as principais plantas daninhas presentes foram: Cyperus rotundus L., Cenchrus echinatus L., Digitaria spp Heist., Echinochloa crus-galli (L. P. Beauv., Brachiaria decumbens Stapf., Eleusine indica Gaertn e Alternanthera tenella Colla. A cultivar de arroz de terras altas Caiapó deve ser mantida sem plantas daninhas nos 30 dias após a emergência.The experiments were carried out in two growing seasons (2003/04 and 2004/05 in an experimental area at São Paulo State University - UNESP, Jaboticabal Campus, to evaluate the weed interference periods on the upland Caiapó rice variety. The experimental design was randomized blocks with 4 replicates and 16 treatments. The treatments consisted of increasing periods of control or coexistence after emergence of the culture: 0-10; 0-20; 0-30; 0-40; 0-50; 0-60; 0-70 days; 0-harvest. The predominant families were Poaceae, Asteraceae, Amaranthaceae and Malvaceae, and the main weeds present were Cyperus rotundus L., Cenchrus echinatus L., Digitaria spp Heist., Echinochloa crus-galli (L. P. Beauv., Brachiaria decumbens Stapf., Eleusine indica Gaertn e Alternanthera tenella Colla for both years. The upland rice cultivar Caiapó is to be kept free of weeds for 30 days after emergence.

  14. Picadas de alimentação de Nezara viridula em cultivares e linhagens de soja de diferentes graus de suscetibilidade Stylet sheath op Nezara viridula in resistant and susceptible soybean varieties

    Directory of Open Access Journals (Sweden)

    C. J. Rossetto

    1981-01-01

    non preference. The varieties IAC 73/228 and IAC 77/656 showed low stylet sheath counts when the pods were not stained and higher counts after staining. This suggests that they have high tolerance to the feeding activity of the green stink bug, not showing much reaction to its feeding activity. It is easier to notice the feeding punctures of the green stink bug on the pods of susceptible varieties than on resistant varieties. The variety IAC 73/228 has been previously shown to suffer low damage caused by green stink bug under field conditions. Both IAC 73/228 and IAC 77/656 are descendents of crosses involving the PI 274454 with the susceptible commercial variety 'Hill'. The Pi 274454 is probably a good source of resistance to the green stink bug. It is a vigorous, procumbent, late maturing variety from the Japanese island of Okinawa.

  15. Comparative Economic Analysis of Rice Production by Adopters and ...

    African Journals Online (AJOL)

    adopters of improved rice varieties among farmers in Paikoro Local Area of Niger State. Primary data were collected using a structured questionnaire administered to 90 respondents, which consist of 45 adopters of improved rice variety and 45 ...

  16. Brown planthopper (N. lugens Stal feeding behaviour on rice germplasm as an indicator of resistance.

    Directory of Open Access Journals (Sweden)

    Mohamad Bahagia A B Ghaffar

    Full Text Available BACKGROUND: The brown planthopper (BPH Nilaparvata lugens (Stal is a serious pest of rice in Asia. Development of novel control strategies can be facilitated by comparison of BPH feeding behaviour on varieties exhibiting natural genetic variation, and then elucidation of the underlying mechanisms of resistance. METHODOLOGY/PRINCIPAL FINDINGS: BPH feeding behaviour was compared on 12 rice varieties over a 12 h period using the electrical penetration graph (EPG and honeydew clocks. Seven feeding behaviours (waveforms were identified and could be classified into two phases. The first phase involved patterns of sieve element location including non penetration (NP, pathway (N1+N2+N3, xylem (N5 [21] and two new feeding waveforms, derailed stylet mechanics (N6 and cell penetration (N7. The second feeding phase consisted of salivation into the sieve element (N4-a and sieve element sap ingestion (N4-b. Production of honeydew drops correlated with N4-b waveform patterns providing independent confirmation of this feeding behaviour. CONCLUSIONS/SIGNIFICANCE: Overall variation in feeding behaviour was highly correlated with previously published field resistance or susceptibility of the different rice varieties: BPH produced lower numbers of honeydew drops and had a shorter period of phloem feeding on resistant rice varieties, but there was no significant difference in the time to the first salivation (N4-b. These qualitative differences in behaviour suggest that resistance is caused by differences in sustained phloem ingestion, not by phloem location. Cluster analysis of the feeding and honeydew data split the 12 rice varieties into three groups: susceptible, moderately resistant and highly resistant. The screening methods that we have described uncover novel aspects of the resistance mechanism (or mechanisms of rice to BPH and will in combination with molecular approaches allow identification and development of new control strategies.

  17. Redox-active pyocyanin secreted by Pseudomonas aeruginosa 7NSK2 triggers systemic resistance to Magnaporthe grisea but enhances Rhizoctonia solani susceptibility in rice.

    Science.gov (United States)

    De Vleesschauwer, David; Cornelis, Pierre; Höfte, Monica

    2006-12-01

    Pseudomonas aeruginosa 7NSK2 induces resistance in dicots through a synergistic interaction of the phenazine pyocyanin and the salicylic acid-derivative pyochelin. Root inoculation of the monocot model rice with 7NSK2 partially protected leaves against blast disease (Magnaporthe grisea) but failed to consistently reduce sheath blight (Rhizoctonia solani). Only mutations interfering with pyocyanin production led to a significant decrease in induced systemic resistance (ISR) to M. grisea, and in trans complementation for pyocyanin production restored the ability to elicit ISR. Intriguingly, pyocyanin-deficient mutants, unlike the wild type, triggered ISR against R. solani. Hence, bacterial pyocyanin plays a differential role in 7NSK2-mediated ISR in rice. Application of purified pyocyanin to hydroponically grown rice seedlings increased H202 levels locally on the root surface as well as a biphasic H202 generation pattern in distal leaves. Co-application of pyocyanin and the antioxidant sodium ascorbate alleviated the opposite effects of pyocyanin on rice blast and sheath blight development, suggesting that the differential effectiveness of pyocyanin with respect to 7NSK2-triggered ISR is mediated by transiently elevated H202 levels in planta. The cumulative results suggest that reactive oxygen species act as a double-edged sword in the interaction of rice with the hemibiotroph M. grisea and the necrotroph R. solani.

  18. Use of molecular markers in identification and characterization of resistance to rice blast in India.

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Yadav

    Full Text Available Rice blast disease caused by Magnaporthe oryzae is one of the most destructive disease causing huge losses to rice yield in different parts of the world. Therefore, an attempt has been made to find out the resistance by screening and studying the genetic diversity of eighty released rice varieties by National Rice Research Institute, Cuttack (NRVs using molecular markers linked to twelve major blast resistance (R genes viz Pib, Piz, Piz-t, Pik, Pik-p, Pikm Pik-h, Pita/Pita-2, Pi2, Pi9, Pi1 and Pi5. Out of which, nineteen varieties (23.75% showed resistance, twenty one were moderately resistant (26.25% while remaining forty varieties (50% showed susceptible in uniform blast nursery. Rice varieties possessing blast resistance genes varied from four to twelve and the frequencies of the resistance genes ranged from 0 to 100%. The cluster analysis grouped the eighty NRVs into two major clusters at 63% level of genetic similarity coefficient. The PIC value for seventeen markers varied from 0 to 0.37 at an average of 0.20. Out of seventeen markers, only five markers, 195R-1, Pi9-i, Pita3, YL155/YL87 and 40N23r corresponded to three broad spectrum R genes viz. Pi9, Pita/Pita2 and Pi5 were found to be significantly associated with the blast disease with explaining phenotypic variance from 3.5% to 7.7%. The population structure analysis and PCoA divided the entire 80 NRVs into two sub-groups. The outcome of this study would help to formulate strategies for improving rice blast resistance through genetic studies, plant-pathogen interaction, identification of novel R genes, development of new resistant varieties through marker-assisted breeding for improving rice blast resistance in India and worldwide.

  19. Breeding high-yielding drought-tolerant rice: genetic variations and conventional and molecular approaches.

    Science.gov (United States)

    Kumar, Arvind; Dixit, Shalabh; Ram, T; Yadaw, R B; Mishra, K K; Mandal, N P

    2014-11-01

    The increased occurrence and severity of drought stress have led to a high yield decline in rice in recent years in drought-affected areas. Drought research at the International Rice Research Institute (IRRI) over the past decade has concentrated on direct selection for grain yield under drought. This approach has led to the successful development and release of 17 high-yielding drought-tolerant rice varieties in South Asia, Southeast Asia, and Africa. In addition to this, 14 quantitative trait loci (QTLs) showing a large effect against high-yielding drought-susceptible popular varieties were identified using grain yield as a selection criterion. Six of these (qDTY 1.1 , qDTY 2.2 , qDTY 3.1 , qDTY 3.2 , qDTY 6.1 , and qDTY 12.1 ) showed an effect against two or more high-yielding genetic backgrounds in both the lowland and upland ecosystem, indicating their usefulness in increasing the grain yield of rice under drought. The yield of popular rice varieties IR64 and Vandana has been successfully improved through a well-planned marker-assisted backcross breeding approach, and QTL introgression in several other popular varieties is in progress. The identification of large-effect QTLs for grain yield under drought and the higher yield increase under drought obtained through the use of these QTLs (which has not been reported in other cereals) indicate that rice, because of its continuous cultivation in two diverse ecosystems (upland, drought tolerant, and lowland, drought susceptible), has benefited from the existence of larger genetic variability than in other cereals. This can be successfully exploited using marker-assisted breeding. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  20. 8155 Volume 13 No. 4 September 2013 EFFECT OF VARIETY ...

    African Journals Online (AJOL)

    BABAWURO

    2013-09-04

    Sep 4, 2013 ... than Ex-China. Row spacings of 15, 20 and 25cm also had significant effects on the number of tillers per plant, number of spikes per hill, number of spikelets per ... Over the past decades, rice has shifted from a luxury to a staple food crop in Nigeria, ... Two varieties of rice, Ex-China (indigenous variety).

  1. Fluoride levels in commercially available rice in Ethiopia | Tegegne ...

    African Journals Online (AJOL)

    Alkaline fusion was used for sample preparation of six varieties for both the raw rice and rice cooked with tap water and fluoridated water. Fluoride levels ... A statistical analysis of variance at 95% confidence level for fluoride determination indicated significant difference between the mean of each variety of rice samples.

  2. Physicochemical properties of germinated brown rice ( Oryza sativa L.)

    African Journals Online (AJOL)

    Physicochemical properties of white rice (WR), brown rice (BR) and germinated brown rice (GBR) starches from a mixed variety of MR219 and MR220, commonly consumed Malaysian varieties, were compared in this study. The granular size of the starch particles, measured using scanning electron microscope (SEM), ...

  3. Habilidade competitiva de plantas de arroz com biótipos de capim-arroz resistente ou suscetível ao quinclorac Competitive ability of rice plants with barnyardgrass biotypes resistant or susceptible to quinclorac

    Directory of Open Access Journals (Sweden)

    S.P. Tironi

    2009-06-01

    Full Text Available Objetivou-se com este trabalho avaliar a habilidade competitiva de plantas de arroz cultivar BRS Pelota com biótipos de capim-arroz resistente ou suscetível ao herbicida quinclorac. Para isso, foi instalado experimento em casa de vegetação, em delineamento completamente casualizado com quatro repetições, sendo os tratamentos dispostos em esquema fatorial 2 x 6. As unidades experimentais constaram de vasos plásticos contendo 10 dm³ de solo, cujo pH e nível de nutrientes foram previamente corrigidos. Os tratamentos consistiram na competição entre uma planta de arroz, cultivar BRS Pelota, com populações (0, 1, 2, 3, 4 ou 5 plantas por vaso dos biótipos de capim-arroz resistente (ECH-13 ou suscetível (ECH-12 ao herbicida quinclorac. As avaliações foram realizadas aos 40 dias após emergência, sendo avaliados; massa seca da parte aérea (MSPA, taxa de crescimento (TC, área foliar específica (AFE, razão de massa foliar (RMF, razão de área foliar (RAF e índice de área foliar (IAF. A interferência no desenvolvimento do cultivar de arroz BRS Pelota foi proporcionalmente maior com o aumento da população de ambos os biótipos de capim-arroz. Os biótipos apresentaram, em geral, habilidade competitiva similar.The objective of this study was to evaluate the competitive ability of the rice cultivar BRS Pelota with biotypes resistant or susceptible to the herbicide Quinclorac. The experiment was conducted under greenhouse conditions in a completely randomized design with four replications, with the treatments arranged in a 2 x 6 factorial. The experimental units consisted of plastic pots containing 10 dm³ of soil, with pH and nutrient level being previously corrected. The treatments consisted of a competition between a rice plant, BRS Pelota cultivar, with populations (0, 1, 2, 3, 4 or 5 plants per pot of the barnyardgrass biotypes resistant (ECH-13 or susceptible (ECH -12 to the herbicide Quinclorac. The evaluations were performed

  4. COMPARATIVE PERFORMANCE OF A LOCALLY DEVELOPED VOTEX RICE FAN THRESHER

    OpenAIRE

    Dauda, S.M.; A. U. Dzivama

    2008-01-01

    The efforts to discover and make optimal and effective use of locally developed rice thresher as substitute for imported rice threshers form the focus of this paper. A locally developed rice thresher was compared with an imported Votex rice fan fromHolland.  The study was based on threshing efficiency, cleaning efficiency, total grain losses, grain recovery range, capacity utilization and threshing intensity. Three popular rice varieties, Faro 51, Faro 29 and Faro 21 were used to evaluate the...

  5. Feasibility study on estimation of rice weevil quantity in rice stock using near-infrared spectroscopy technique

    Directory of Open Access Journals (Sweden)

    Puttinun Jarruwat

    2014-07-01

    Full Text Available Thai rice is favored by large numbers of consumers of all continents because of its excellent taste, fragrant aroma and fine texture. Among all Thai rice varieties, Thai Hommali rice is the most preferred. Classification of rice as premium quality requires that almost all grain kernels of the rice be perfectly whole with only a small quantity of foreign particles. Of all the foreign particles found in rice, rice weevils can wreck severest havoc on the quality and quantity of rice such that premium grade rice is transformed into low grade rice. It is widely known that rice millers adopt the "overdose" fumigation practice to control the birth and propagation of rice weevils, the practice of which inevitably gives rise to pesticide residues on rice which end up in the body of consumers. However, if population concentration of rice weevils could be approximated, right amounts of chemicals for fumigation would be applied and thereby no overdose is required. The objective of this study is thus to estimate the quantity of rice weevils in both milled rice and brown rice of Thai Hommali rice variety using the near infrared spectroscopy (NIRS technique. Fourier transforms near infrared (FT-NIR spectrometer was used in this research and the near-infrared wavelength range was 780–2500 nm. A total of 20 levels of rice weevil infestation with an increment of 10 from 10 to 200 mature rice weevils were applied to 1680 rice samples. The spectral data and quantity of weevils are analyzed by partial least square regression (PLSR to establish the model for prediction. The results show that the model is able to estimate the quantity of weevils in milled Hommali rice and brown Hommali rice with high $R_{\\rm val}^{2}$ of 0.96 and 0.90, high RPD of 6.07 and 3.26 and small bias of 2.93 and 2.94, respectively.

  6. Phylogenetic diversity and relationships among 40 rice accessions ...

    African Journals Online (AJOL)

    SERVER

    , there is the need to diversify the genetic base of improved rice varieties, and the first step towards this is to evaluate and characterise available rice germplasm or genotypes at both the morphological and molecular levels. This is because the.

  7. Genetic analysis of Resistance to Rice Bacterial blight in Uganda ...

    African Journals Online (AJOL)

    Rice bacterial blight (Xanthomonas oryzae pv.oryzae) is a major constraint to rice (Oryza sativa L.) production in Uganda and as part of strategies to develop resistant cultivars, it is important to evaluate resistance of commonly used cultivars. A full-diallel mating design involving three resistant and three susceptible rice ...

  8. Interaction of Paddy Varieties and Compost with Flux of Methane in Tidal Swampland

    Directory of Open Access Journals (Sweden)

    Andin Muhammad Abduh

    2016-09-01

    Full Text Available Paddy variety and organic material have a very important role on the flux of methane (CH4 in rice cultivation, especially in a swamp land. The purpose of this study was to determine the amount of methane emissions released from rice cultivation in acid sulphate soils with the use of different rice straw varieties and composts. This study used a 2 × 2 factorial in a Completely Randomized Design with six replicates. The first factor was rice varieties and the second factor was rice straw compost. The results showed that the smallest emision rate of CH4 occurred when using Inpara 3 variety without rice straw compost of 0.030 mg.m 2. day-1, while the largest occured when using Inpari 30 variety with 5 Mg rice straw compost ha-1 that was equal to 0.571 mg m-2 day-1.

  9. 7 CFR 201.10 - Variety.

    Science.gov (United States)

    2010-01-01

    ..., Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.10 Variety. (a) The following kinds of agricultural seeds are generally..., striate; Millet, foxtail; Millet, pearl; Oat; Pea, field; Peanut; Rice; Rye; Safflower; Sorghum; Sorghum...

  10. Rice Nutrition

    Science.gov (United States)

    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...

  11. A feasibility study on identification of Basmati (aromatic) rice using ...

    Indian Academy of Sciences (India)

    basis of characterization of rice crop into two different varieties namely aromatic and non-aromatic. Multitemporal HH polarization data along with rate of change of cross polarization ratio (HH/HV) from. July to September 2011 was used. The aromatic rice could be separated from normal rice with 91% accuracy. 1.

  12. Genomic diversity among Basmati rice ( Oryza sativa L) mutants ...

    African Journals Online (AJOL)

    Genomic diversity among Basmati rice ( Oryza sativa L) mutants obtained through 60 Co gamma radiations using AFLP markers. ... In order to obtain new varieties of rice with improved agronomic and grain characteristics, gamma radiation (60Co) has been used to generate novel mutants of the Basmati rice. In this study ...

  13. Agromorphological characterization of some rice species in the main ...

    African Journals Online (AJOL)

    Rice is the basic cereal of the populations of the areas of Tandjilé and Western Mayo Kebbi, in the south of Chad. The rice productivity is, however, low: less than 1 t/ha. This is related to several factors, of which the strong infestation of rice plantation into adventitious and lack of improved varieties with high productivity.

  14. Genetic diversity in grain quality and nutrition of aromatic rices ...

    African Journals Online (AJOL)

    The study was conducted at Bangladesh Rice Research Institute (BRRI), Gazipur in 2005 to assess the genetic divergence of aromatic rices for grain quality and nutrition aspects. Forty genotypes composed of 32 local aromatic, five exotic aromatic and three non-aromatic rice varieties were used. Univariate and multivariate ...

  15. The puzzle of Italian rice origin and evolution: determining genetic divergence and affinity of rice germplasm from Italy and Asia.

    Directory of Open Access Journals (Sweden)

    Xingxing Cai

    Full Text Available The characterization of genetic divergence and relationships of a set of germplasm is essential for its efficient applications in crop breeding and understanding of the origin/evolution of crop varieties from a given geographical region. As the largest rice producing country in Europe, Italy holds rice germplasm with abundant genetic diversity. Although Italian rice varieties and the traditional ones in particular have played important roles in rice production and breeding, knowledge concerning the origin and evolution of Italian traditional varieties is still limited. To solve the puzzle of Italian rice origin, we characterized genetic divergence and relationships of 348 rice varieties from Italy and Asia based on the polymorphisms of microsatellite fingerprints. We also included common wild rice O. rufipogon as a reference in the characterization. Results indicated relatively rich genetic diversity (H(e = 0.63-0.65 in Italian rice varieties. Further analyses revealed a close genetic relationship of the Italian traditional varieties with those from northern China, which provides strong genetic evidence for tracing the possible origin of early established rice varieties in Italy. These findings have significant implications for the rice breeding programs, in which appropriate germplasm can be selected from a given region and utilized for transferring unique genetic traits based on its genetic diversity and evolutionary relationships.

  16. Functional genomics strategies with transposons in rice

    NARCIS (Netherlands)

    Greco, R.

    2003-01-01

    Rice is a major staple food crop and a recognizedmonocotylenedousmodel plant from which gene function discovery is projected to contribute to improvements in a variety of cereals like wheat and maize. The recent release of rough drafts of the rice genome sequence for public

  17. FLUORIDE LEVELS IN COMMERCIALLY AVAILABLE RICE IN ...

    African Journals Online (AJOL)

    Preferred Customer

    2013-05-05

    May 5, 2013 ... shattering-prone Oryza glaberrima. It contains 2% more protein than their African or Asian parents. It is taller than most rice, making harvesting easier, pest resistant and tolerant to drought and infertile soils better than Asian varieties [18]. Rice is a cereal foodstuff which forms an important part of the diet of ...

  18. Extensive sequence variation in rice blast resistance gene Pi54 makes it broad spectrum in nature

    Directory of Open Access Journals (Sweden)

    Shallu eThakur

    2015-05-01

    Full Text Available Rice blast resistant gene, Pi54 cloned from rice line, Tetep, is effective against diverse isolates of Magnaporthe oryzae. In this study, we prospected the allelic variants of the dominant blast resistance gene from a set of 92 rice lines to determine the nucleotide diversity, pattern of its molecular evolution, phylogenetic relationships and evolutionary dynamics, and to develop allele specific markers. High quality sequences were generated for homologs of Pi54 gene. Using comparative sequence analysis, InDels of variable sizes in all the alleles were observed. Profiling of the selected sites of SNP (Single Nucleotide Polymorphism and amino acids (N sites ≥ 10 exhibited constant frequency distribution of mutational and substitutional sites between the resistance and susceptible rice lines, respectively. A total of 50 new haplotypes based on the nucleotide polymorphism was also identified. A unique haplotype (H_3 was found to be linked to all the resistant alleles isolated from indica rice lines. Unique leucine zipper and tyrosine sulfation sites were identified in the predicted Pi54 proteins. Selection signals were observed in entire coding sequence of resistance alleles, as compared to LRR domains for susceptible alleles. This is a maiden report of extensive variability of Pi54 alleles in different landraces and cultivated varieties, possibly, attributing broad-spectrum resistance to Magnaporthe oryzae. The sequence variation in two consensus region: 163 bp and 144 bp were used for the development of allele specific DNA markers. Validated markers can be used for the selection and identification of better allele(s and their introgression in commercial rice cultivars employing marker assisted selection.

  19. Association mapping of stigma and spikelet characteristics in rice (Oryza sativa L.)

    Science.gov (United States)

    Hybrid rice exhibits a yield advantage of 15 to 20 percent (or more than one ton of paddy rice per hectare) over the best traditional varieties. Because rice plants are self-pollinating, commercial production of hybrid seed plays a key role in successful implementation of hybrid rice. Stigma exserti...

  20. Breeding elite japonica-type soft rice with high protein content ...

    African Journals Online (AJOL)

    rice grains. In an attempt to analyze whether the anti-Waxy gene could increase protein content while reducing amylose content in the rice grains, and develop good soft rice varieties with high protein content, an anti-Waxy gene was introduced into the high-yield japonica rice strain, Shangshida No. 2. The amylose contents ...

  1. Two-component cultivar mixtures reduce rice blast epidemics in an upland agrosystem

    OpenAIRE

    Raboin, L. M.; Ramanantsoanirina, A.; Dusserre, J.; Razasolofonanahary, F.; Tharreau, Didier; Lannou, Christian; Sester, M.

    2012-01-01

    The effect of two-component rice cultivar mixtures on the control of rice blast disease was studied in three different experiments under rainfed upland conditions in the Madagascar Highlands. The mixtures involved a susceptible cultivar (either susceptible or very susceptible) and a resistant cultivar in different mixture arrangements (random or row mixtures) and with different proportions of the susceptible cultivar (50, 20 and 16.7%), which were compared to the susceptible cultivar grown in...

  2. The use of induced mutation combined with crossing in high quality rice breeding

    Energy Technology Data Exchange (ETDEWEB)

    Do Huu At; Bui Huy Thuy; Nguyen Van Bich; Tran Duy Quy [Agricultural Genetics Institute, Division of Genetics and Hybrid Rice Technology, Hanoi (Viet Nam); Nguyen Minh Cong [Hanoi No. 1 Teacher Training Univ., Department of Genetics (Viet Nam)

    2001-03-01

    The high quality rice varieties: Tam thom mutant rice Var., DT17 rice Var, DT21 glutinous rice Var were formed by induced mutation combined with crossing. Tam thom mutant rice Var. lost photosensitivity, could be planted 2 crops/year. DT17 rice Var with high yielding capacity, suitable for growth on lowland in summer crop, is replacing step-by-step Moctuyen rice Var. in North Vietnam. DT21 glutinous rice Var. could be planted 2 crops/year and had short growth duration, average yield was 4.0-4.5 tons/ha. These three ones had good quality, soft and scent cooked rice, suitable for customers and export requirements. Tam thom mutant rice Var. DT17 rice Var., DT21 and glutinous rice Var. were adopted for regional production by Ministry of Agriculture and Rural Development and allowed to be in trial production. (author)

  3. Determinants of Yield Gap in Lowland Rice Production in North ...

    African Journals Online (AJOL)

    Results indicated that rice farmers in the area cultivated four improved rice varieties WITA 4, FARO 15, FARO 35 and FARO 44 with average yield gaps of 1.48, 2.85, 3.03 and 3.20 tons per hectare respectively. This makes these rice varieties under-exploited as farmers operate at levels where they obtain an average of 49% ...

  4. Bioethanol production from rice straw residues

    Directory of Open Access Journals (Sweden)

    Elsayed B. Belal

    2013-01-01

    Full Text Available 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 ºC, 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.

  5. Iron biofortification of Myanmar rice

    Directory of Open Access Journals (Sweden)

    May Sann Aung

    2013-05-01

    Full Text Available Iron (Fe deficiency causes 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 and/or 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.

  6. Decrease in catalase activity of Folsomia candida fed a Bt rice diet

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Yiyang, E-mail: yuanyy@ioz.ac.cn [State Key Laboratory of Integrated Management of Pest and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101 (China); Graduate School, Chinese Academy of Sciences, Beijing 100039 (China); Ke Xin, E-mail: xinke@sibs.ac.cn [Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032 (China); Chen Fajun, E-mail: fajunchen@njau.edu.cn [College of Plant Protection, Department of Entomology, Nanjing Agricultural University, Nanjing 210095 (China); Krogh, Paul Henning, E-mail: phk@dmu.dk [Department of Bioscience, University of Aarhus, P.O. Box 314, Vejlsoevej 25, DK-8600 Silkeborg (Denmark); Ge Feng, E-mail: gef@ioz.ac.cn [State Key Laboratory of Integrated Management of Pest and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101 (China)

    2011-12-15

    Here we report the effects of three Bt-rice varieties and their non-Bt conventional isolines on biological traits including survival, reproduction, and the activities of three antioxidant enzymes superoxide dismutase, catalase and peroxidase, in the Collembolan, Folsomia candida. The reproduction was significantly lower when fed Kemingdao and Huahui1 than those feeding on their non-GM near-isogenic varieties Xiushui and Minghui63 respectively, this can be explained by the differences of plant compositions depended on variety of rice. The catalase activity of F. candida was significantly lower when fed the Bt-rice variety Kemingdao compared to the near-isogenic non-Bt-rice variety Xiushui. This suggests that some Bt-rice varieties may impose environmental stress to collembolans. We emphasize that changes in activity of antioxidant enzymes of non-target organisms are important in understanding the ecological consequences for organisms inhabiting transgenic Bt-rice plantations. - Highlights: > We examine the effects of Bt-rice on Folsomia candida with laboratory test. > The reproduction of F. candida was decreased by two Bt-rice varieties. > Decreased reproduction caused by the differences of varieties or C/N ratio of rice. > The catalase activity was decreased by Bt-rice Kemingdao. > Some Bt-rice may impose environmental stress on NTOs. - The catalase of the collembolan (Folsomia candida) was decreased when fed Bt-rice, Kemingdao.

  7. Efficiency of soil and fertilizer nitrogen in relation to rice variety and application time using sup(15)N labelled fertilizer: Pt. 4. Pot experiment for split application of sup(15)N-urea

    Energy Technology Data Exchange (ETDEWEB)

    Park, H. (Korea Ginseng and Tobacco Research Inst., Seoul (Republic of Korea)); Kim, U.J. (Office of Rural Development, Suwon (Republic of Korea))

    1982-09-01

    Top-dressing pot experiment with sup(15)N urea was carried out by using three varieties. Two-split application was much better for Tongil line than 4-split. Fertilization efficiency(Fe), use efficiency(Eu) and absorbed fertilizer nitrogen efficiency (Ef) were much greater in 2-split than in 4-split. The order of Fe followed that of Ef. Grain yield and sup(15)N excess % among plant parts suggest that Tongil line uptakes fertilizer nitrogen much in early stage and retranslocated well later. The order of soil nitrogen increment in plant per fertilizer nitrogen in plant (..delta..Ns/Nf) might be an index of soil nitrogen use efficiency due to fertilizer.

  8. Efficiency of soil and fertilizer nitrogen in relation to rice variety and application time using sup(15)N labelled fertilizer: Pt. 3. Top-dressing with sup(15)N fertilizer in fields

    Energy Technology Data Exchange (ETDEWEB)

    Park, H. (Korea Ginseng and Tobacco Research Inst., Seoul (Republic of Korea)); Seok, S.J. (Office of Rural Development, Suwon (Republic of Korea))

    1982-09-01

    Use efficiency of top-dressed labelled nitrogen (30% at ear formation stage) ranged 23 to 61%(five fields) with no clear difference between varieties. In high yield soil the use efficiency of top-dressed nitrogen was higher and more than 50% of fertilizer nitrogen in plant seemed to be taken up after ear formation, sup(15)N excess was greastest in grain indicating that top-dressed nitrogen translocates easily to grain. The differences of sup(15)N excess between grain and straw was greater in Tongil line than in the local indicating faster nitrogen translocation in Tongil. Percent nitrogen derived from top-dressed nitrogen ranged 14 to 27% in aerial part. Two 3-hill plots per treatment could be enough for sup(15)N experiment under field condition if there is specific care.

  9. Molecular characterization of traditional and improved rice cultivars ...

    African Journals Online (AJOL)

    Sadia

    2012-06-05

    Jun 5, 2012 ... commercial varieties and primitive cultivars of Rice (Oryza sativa L.) were established by using random amplified polymorphic DNAs .... RAPD markers have also been used to identify and tag the important genes for ... 35 commercial varieties and obsolete cultivars (Table 1) of rice from germplasm unit of ...

  10. Determinants of Yield Gap in Upland Rice Production in ...

    African Journals Online (AJOL)

    Respondents cultivated three improved rice varieties – ITA 150, WAB 189 and FARO 55 with average yield gaps of 1.52, 1.38 and 0.91 tons per hectare, respectively. This makes these rice varieties under-exploited as farmers operate at levels where they obtain an average of 49% of the potential yield. Factors which would ...

  11. Quantitative and qualitative damage caused by Oebalus poecilus (Hemiptera, Pentatomidae to upland rice cultivated in new agricultural frontier of the Amazon rainforest (Brazil

    Directory of Open Access Journals (Sweden)

    Diones Krinski

    Full Text Available ABSTRACT Oebalus poecilus (Dallas 1851 is one of the stink bug species of great economic importance for rice producers in Brazil of irrigated, flood and upland cropping systems. These pentatomids are known as stink bugs of panicles, because both nymphs and adults feed mainly on panicles. Stink bug attacks result in pecky (spots seeds, lower mass, germinative reduction and deformed grains. Bearing these factors in mind, the aim of this study was to evaluate the quantitative and qualitative losses in commercial cultivars of upland rice (Cambará variety, submitted to different population levels of stink bugs of panicles, O. poecilus, at different reproductive growth stages. The results show that in upland rice (Cambará variety, the rice grains are susceptible to quantitative (number and weight and qualitative (pecky, atrophy, chalky and broken grains damage during all panicle development. However, when the insects feed during anthesis/caryopsis and milky stage cause significantly greater percentage of empty grains (up to 83% than when they feed of grains during later phases of panicle development. This characteristic was also observed for the reduction in grain weight. This information may benefit producers and other researchers, allowing them to focus on the monitoring efforts of O. poecilus in most susceptible phases of the attack of this insect. This will enable decision-making about what control measures should be taken, and when, in order to control stink bugs of panicles.

  12. Effect of Salt Stress on Germination and Growth Parameters of Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Akinbode Foluso OLOGUNDUDU

    2014-06-01

    Full Text Available The response of eight varieties of Oryza sativa L. (‘NERICA 1’, ‘NERICA 5’, ‘NERICA 12’, ‘NERICA 19’, ‘IR 29’, ‘IR 20’, ‘IWA 11’, and ‘POKKALI’, a salt tolerant check against four salinity levels (0, 5, 10, and 15 ds m-1 were studied at germination and early growth stages. Data were analyzed using Statistical Analytical System (SAS and means were separated by Duncan Multiple Range Test (DMRT for Final Germination Percentage (FGP, Speed of Germination (SG, Germination Energy Percentage (GE%, shoot and root length and root and shoot dry weight. Based on dry matter yield reduction, rice varieties were classified as tolerant (T, moderately tolerant (MT, moderately susceptible (MS or susceptible (S. Germination was not recorded at 20 ds m-1 salt concentration in all cultivars. Salinity decreased FGP, SG, GE% and led to reduction in shoot and root length and dry weight in all varieties and the magnitude of reduction increased with increasing salinity stress. Rice varieties ‘NERICA 12’, ‘IR 20’, ‘IWA 11’ and ‘NERICA 19’ showed greater salt tolerance during germination (germinated at 10 ds m-1 salinity. However, ‘NERICA 1’, ‘IR 29’, and ‘IR 20’ performed better based on dry matter yield reduction. The result suggested that ‘NERICA 1’, ‘IR 29’, and ‘IR 20’ might be used for further study of salinity effect on growth processes and physiological consequences at advanced stage of growth. The physiological responses of rice plants to salinity at various developmental stages are therefore critical for identifying salinity tolerance in the cultivars.

  13. Pyrosequencing-Based Transcriptome Analysis of the Asian Rice Gall Midge Reveals Differential Response during Compatible and Incompatible Interaction

    Directory of Open Access Journals (Sweden)

    Jagadish S. Bentur

    2012-10-01

    Full Text Available The Asian rice gall midge (Orseolia oryzae is a major pest responsible for immense loss in rice productivity. Currently, very little knowledge exists with regard to this insect at the molecular level. The present study was initiated with the aim of developing molecular resources as well as identifying alterations at the transcriptome level in the gall midge maggots that are in a compatible (SH or in an incompatible interaction (RH with their rice host. Roche 454 pyrosequencing strategy was used to develop both transcriptomics and genomics resources that led to the identification of 79,028 and 85,395 EST sequences from gall midge biotype 4 (GMB4 maggots feeding on a susceptible and resistant rice variety, TN1 (SH and Suraksha (RH, respectively. Comparative transcriptome analysis of the maggots in SH and RH revealed over-representation of transcripts from proteolysis and protein phosphorylation in maggots from RH. In contrast, over-representation of transcripts for translation, regulation of transcription and transcripts involved in electron transport chain were observed in maggots from SH. This investigation, besides unveiling various mechanisms underlying insect-plant interactions, will also lead to a better understanding of strategies adopted by insects in general, and the Asian rice gall midge in particular, to overcome host defense.

  14. The Potential of Dark Purple Scented Rice- From Staple Food to Nutraceutical

    OpenAIRE

    Kangabam Rajiv Das; Kangabam Medhabati; Khumu kcham Nongalleima; Huidrom Sunitibala Devi

    2014-01-01

    Among the rice varieties, Purple Rice has an incredibly rich history and counts among its strains one variety known as Imperial rice as they are reserved for the Emperor’s consumption only. The purple color is due to high anthocyanin content, a trait most typically observed in fruits. There are abundant benefits including medicinal properties of rice. Its medicinal properties being imparted by the phytochemicals present in it, some of the important compounds which are worth mentioning are toc...

  15. Effects of Cadmium Stress on the Quality of Rice Seeds

    OpenAIRE

    CHEN, Juan; FANG, Hui; ZHANG, Ying; FAN, Yuanyuan

    2013-01-01

    Germination and hydroponic experiments are performed on rice seeds growing in soils treated with Cd stress, with rice seeds of the same variety that is not treated with Cd stress as a control, to study the effects of Cd stress on quality of rice seeds. The results have shown that: (1) Cd stress reduces the thousand grain weight of rice seeds, and higher Cd content means lower thousand grain weight; (2) The germination vigor and germination percentage of rice seeds under Cd stress as well as t...

  16. Non-destructive detection for mold colonies in rice based on hyperspectra and GWO-SVR.

    Science.gov (United States)

    Sunli, Cong; Jun, Sun; Hanping, Mao; Xiaohong, Wu; Pei, Wang; Xiaodong, Zhang

    2017-08-08

    Mold contamination of grains not only contributes to inedible food, resulting in economic losses, but also leads to mold in humans and livestock, and can even be carcinogenic to them. Rice, as one of the main grain varieties, if stored improperly, is easily susceptible to mildew. In order to detect the total number of mold colonies in rice more accurately, a method based on hyperspectral imaging technology was investigated. In this paper, non-destructive detection for the total number of mold colonies in rice was performed from the angle of spectral analysis. A determination coefficient of 0.9621 for the calibration set and 0.9511 for the prediction set between the spectral data and number of mold colonies were eventually achieved by establishing the best support vector regression (SVR) model, optimized by the Gray Wolf Optimization (GWO) algorithm. Hyperspectral imaging technology combined with the optimal model (GWO-SVR) is feasible for non-destructive detection of the total number of mold colonies in rice, providing a promising tool for the mold detection of other agricultural products. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  17. VARIEDADES DE CITROS MAIS SUSCETÍVEIS AO ATAQUE DE Macropophora accentifer (OLIVIER, 1795 COLEOPTERA CERAMBYCIDAE VARIETIES OF CITRUS MORE SUSCEPTIBLE TO THE ATTACK OF Macropophora accentifer (OLIVIER, 1975 COLEOPTERA, CERAMBYCIDAE

    Directory of Open Access Journals (Sweden)

    Antônio Henrique Garcia

    2007-09-01

    recapture were carried out in September/October/November, and in March/April/May. A total of 231 females insects were collected in each variety, labeled and immediately released in different varieties, including those who collected firstly. The recaptures were carried out twelve days after each release; 30 releases and 50 recaptures were performed. The preference was determined considering the number of female insects that remained, returned or migrated to each one of the citrus varieties. It was observed that 2.16% of the females returned to the varieties where they were previously collected, 59.31% remained in the variety where they were released, 30.74% migrated to different varieties, and 7.79% were not recaptured. The cravo tangerine presented 46.75% of preference, followed by tangor sabará with 16.88%, baianinha orange with 10.82%, natal orange with 9.95% and rio tangerine with 7.8%. Cravo lemon did not present any preference by the insect females.

  18. Participatory variety selection to enhance cowpea variety ...

    African Journals Online (AJOL)

    ACSS

    Participatory variety selection trials involving farmers in northern Uganda were conducted in order to assess and select cowpea lines with desirable attributes and tolerance to virus infection. The trials were set up on-farm in farmers' field in the districts of Apac, Lira and Pader in two seasons of 2009A and 2009B. In 2009A ...

  19. Rice epigenomics and epigenetics: challenges and opportunities.

    Science.gov (United States)

    Chen, Xiangsong; Zhou, Dao-Xiu

    2013-05-01

    During recent years rice genome-wide epigenomic information such as DNA methylation and histone modifications, which are important for genome activity has been accumulated. The function of a number of rice epigenetic regulators has been studied, many of which are found to be involved in a diverse range of developmental and stress-responsive pathways. Analysis of epigenetic variations among different rice varieties indicates that epigenetic modification may lead to inheritable phenotypic variation. Characterizing phenotypic consequences of rice epigenomic variations and the underlining chromatin mechanism and identifying epialleles related to important agronomic traits may provide novel strategies to enhance agronomically favorable traits and grain productivity in rice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Production of transgenic rice with agronomically useful genes: an assessment.

    Science.gov (United States)

    Giri, C C; Vijaya Laxmi, G

    2000-12-01

    Rice is the most important food crop in tropical and subtropical regions of the world. Yield enhancement to increase rice production is one of the essential strategies to meet the demand for food of the growing population. Both abiotic and biotic features limit adversely the productivity of rice growing areas. Conventional breeding has been an effective means for developing high yielding varieties, however; it is associated with its own limitations. It is envisaged that recent trends in biotechnology can contribute to the agronomic improvement of rice in terms of yield and nutritional quality as a supplement to traditional breeding methods. Genetic transformation of rice has demonstrated numerous important opportunities resulting in the genetic improvement of existing elite rice varieties and production of new plant types. Significant advances have been made in the genetic engineering of rice since the first transgenic rice plant production in the late 1980s. Several gene transfer protocols have been employed successfully for the introduction of foreign genes to rice. In more than 60 rice cultivars belonging to indica, japonica, javanica, and elite African cultivars, the protocol has been standardized for transgenic rice production. Selection and use of appropriate promoters, selectable markers, and reporter genes has been helpful for development of efficient protocols for transgenic rice in a number of rice cultivars. The present review is an attempt to assess the current state of development in transgenic rice for the transfer of agronomically useful genes, emphasizing the application and future prospects of transgenic rice production for the genetic improvement of this food crop.

  1. Classification of Malaysia aromatic rice using multivariate statistical analysis

    Science.gov (United States)

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

    2015-05-01

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

  2. Classification of Malaysia aromatic rice using multivariate statistical analysis

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-15

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

  3. Effect of red rice interference in fourth densities of commercial rice.

    Directory of Open Access Journals (Sweden)

    Jorge García de la Osa

    2011-12-01

    Full Text Available Field trials were carried out in The Regional Research Grain Station “Sur del Jíbaro”, Sancti Spíritus, in order to study the infestation effect of 0, 12, 25, 50, 100 and 200 red rice plants per square meter (m2 on growth and yields of commercial variety J-104, seeded at 50, 100, 200 and 300 plants/m². Yield of J-104 rice variety decreased with the increase in red rice density. Crop yield decrease in the dry season ranged from 10.7 to 94.8% with infestations of 12 and 200 red rice plants /m², respectively; while in the wet season changed from 11.4 to 91.5 % with similar level in infestations. In both seasons 12 red rice plants were enough to cause a significant reduction in commercial rice yields in relation to the control treatment (without red rice infestation. The lost in crop yield was due to the decreased in panicles/ m² and filled grains per panicle, caused by the interference with red rice.

  4. Different patterns of gene expression in rice varieties undergoing a ...

    African Journals Online (AJOL)

    Some genes specifically up-regulated in infected 9804-Rxo1 were defenserelated, including the genes encoding pathogenesis-related protein, terpene synthase family, transcription factors (TFs) AP2 domain containing protein, myb-like deoxyribonucleic acid (DNA)- binding domain containing protein, and C2H2-type ...

  5. Allelopathic potential of selected rice varieties | Karim | African ...

    African Journals Online (AJOL)

    Journal Home > Vol 11, No 88 (2012) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat ...

  6. Varieties of English.

    Science.gov (United States)

    Brook, G. L.

    The English language is not a monolithic entity but an amalgam of many different varieties that can be associated respectively with groups of speakers, with individuals, and with the occasion. Among such varieties are slang, regional and class dialects, the language of children, and the language used by public speakers, journalists, lawyers,…

  7. Delivering golden rice to developing countries.

    Science.gov (United States)

    Mayer, Jorge E

    2007-01-01

    Micronutrient deficiencies create a vicious circle of malnutrition, poverty, and economic dependency that we must strive to break. Golden Rice offers a sustainable solution to reduce the prevalence of vitamin A deficiency-related diseases and mortality, a problem that affects the health of millions of children in all developing countries. The technology is based on the reconstitution of the carotenoid biosynthetic pathway by addition of 2 transgenes. The outcome of this high-tech approach will be provided to end users as nutrient-dense rice varieties that are agronomically identical to their own, locally adapted varieties. This intervention has the potential to reach remote rural populations without access to fortification and supplementation programs. As part of our delivery strategy, we are partnering with government and nongovernment, national and international agricultural institutions to navigate through cumbersome and expensive regulatory regimes that affect the release of genetically modified crops, and to create local demand for the biofortified rice varieties.

  8. Effect of Salt Stress on Germination and Growth Parameters of Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Akinbode Foluso OLOGUNDUDU

    2014-06-01

    Full Text Available The response of eight varieties of Oryza sativa L. (‘NERICA 1’, ‘NERICA 5’, ‘NERICA 12’, ‘NERICA 19’, ‘IR 29’, ‘IR 20’, ‘IWA 11’, and ‘POKKALI’, a salt tolerant check against four salinity levels (0, 5, 10, and 15 ds m-1 were studied at germination and early growth stages. Data were analyzed using Statistical Analytical System (SAS and means were separated by Duncan Multiple Range Test (DMRT for Final Germination Percentage (FGP, Speed of Germination (SG, Germination Energy Percentage (GE%, shoot and root length and root and shoot dry weight. Based on dry matter yield reduction, rice varieties were classified as tolerant (T, moderately tolerant (MT, moderately susceptible (MS or susceptible (S. Germination was not recorded at 20 ds m-1 salt concentration in all cultivars. Salinity decreased FGP, SG, GE% and led to reduction in shoot and root length and dry weight in all varieties and the magnitude of reduction increased with increasing salinity stress. Rice varieties ‘NERICA 12’, ‘IR 20’, ‘IWA 11’ and ‘NERICA 19’ showed greater salt tolerance during germination (germinated at 10 ds m-1 salinity. However, ‘NERICA 1’, ‘IR 29’, and ‘IR 20’ performed better based on dry matter yield reduction. The result suggested that ‘NERICA 1’, ‘IR 29’, and ‘IR 20’ might be used for further study of salinity effect on growth processes and physiological consequences at advanced stage of growth. The physiological responses of rice plants to salinity at various developmental stages are therefore critical for identifying salinity tolerance in the cultivars.

  9. Development of mucoadhesive buccal films from rice for pharmaceutical delivery systems.

    Science.gov (United States)

    Okonogi, Siriporn; Khongkhunthian, Sakornrat; Jaturasitha, Sanchai

    2014-12-01

    The aim of this work was to investigate the suitable rice varieties for developing pharmaceutical buccal films. Two rice varieties with extreme difference in amylose content were used. Rice powders were chemically modified to yield the carboxymethyl rice prior to film preparation. Scanning electron microscope (SEM) and X-ray diffractometer (XRD) were used to investigate the solid structure of rice powders. The results indicated that amylose content in the rice grains played the effects on the morphology and crystalline structure of the modified rice powders as well as the film properties. The modified rice powders of low amylose content showed halo pattern XRD whereas some crystalline peaks could be observed from the high amylose content modified rice powders. Adding of glycerin caused the films better properties of more transparency and getting rid of air bubbles. High amylose rice films showed more transparency and higher mucoadhesive property and was considered to be suitable for incorporating the drug. Adding of surfactant caused the increase in tensile strength and decrease in elongation of the rice films. The most suitable surfactant for diclofenac buccal rice film is Tween 20. This study demonstrates that rice grains are the promising natural source for pharmaceutical film forming agent. Suitable pharmaceutical buccal films could be developed from the rice with high amylose content.

  10. Rice seed quality as influenced by storage duration and package ...

    African Journals Online (AJOL)

    The study aimed at evaluating the changes in rice seed quality as a function of storage duration and package type through characterization of seed quality determinants. Two rice varieties NERICA8 and NERICAL56) were measured into four package types (nylon bag, polyethylene bag, jute bag, and paper bag) and stored ...

  11. Adoption of Rice Technologies Introduced by the United States ...

    African Journals Online (AJOL)

    The mean total rice farm land owned by PFs was 2.99 hectares mainly on rented basis, while majority got information on rice production and processing from the project. The project farmers highly adopted the following innovations; use of FARO 44 seed variety, carrying out a seed germination test before planting, carrying ...

  12. Production Efficiency of Swamp Rice Production in Cross River ...

    African Journals Online (AJOL)

    397.00k with N9.80K made on every naira invested in improved variety of swamp rice produced in the study area. Rice farming business is a profitable business, with attractive net return on investment. Therefore, unemployed youths in Cross River ...

  13. Avian foods, foraging and habitat conservation in world rice fields

    Science.gov (United States)

    Stafford, J.D.; Kaminski, R.M.; Reinecke, K.J.

    2010-01-01

    Worldwide, rice (Oryza sativa) agriculture typically involves seasonal flooding and soil tillage, which provides a variety of microhabitats and potential food for birds. Water management in rice fields creates conditions ranging from saturated mud flats to shallow (waste rice) is typically the most abundant potential food of birds in rice fields, with estimates of seed mass from North America ranging from 66672 kg/ha. Although initially abundant after harvest, waste rice availability can be temporally limited. Few abundance estimates for other foods, such as vertebrate prey or forage vegetation, exist for rice fields. Outside North America, Europe and Japan, little is known about abundance and importance of any avian food in rice fields. Currently, flooding rice fields after harvest is the best known management practice to attract and benefit birds. Studies from North America indicate specific agricultural practices (e.g. burning stubble) may increase use and improve access to food resources. Evaluating and implementing management practices that are ecologically sustainable, increase food for birds and are agronomically beneficial should be global priorities to integrate rice production and avian conservation. Finally, land area devoted to rice agriculture appears to be stable in the USA, declining in China, and largely unquantified in many regions. Monitoring trends in riceland area may provide information to guide avian conservation planning in rice-agriculture ecosystems.

  14. Three geographically separate domestications of Asian rice.

    Science.gov (United States)

    Civáň, Peter; Craig, Hayley; Cox, Cymon J; Brown, Terence A

    2015-11-02

    Domesticated rice (Oryza sativa L.) accompanied the dawn of Asian civilization(1) and has become one of world's staple crops. From archaeological and genetic evidence various contradictory scenarios for the origin of different varieties of cultivated rice have been proposed, the most recent based on a single domestication(2,3). By examining the footprints of selection in the genomes of different cultivated rice types, we show that there were three independent domestications in different parts of Asia. We identify wild populations in southern China and the Yangtze valley as the source of the japonica gene pool, and populations in Indochina and the Brahmaputra valley as the source of the indica gene pool. We reveal a hitherto unrecognized origin for the aus variety in central India or Bangladesh. We also conclude that aromatic rice is a result of a hybridization between japonica and aus, and that the tropical and temperate versions of japonica are later adaptations of one crop. Our conclusions are in accord with archaeological evidence that suggests widespread origins of rice cultivation(1,4). We therefore anticipate that our results will stimulate a more productive collaboration between genetic and archaeological studies of rice domestication, and guide utilization of genetic resources in breeding programmes aimed at crop improvement.

  15. Low-level maternal methylmercury exposure through rice ingestion and potential implications for offspring health

    Energy Technology Data Exchange (ETDEWEB)

    Rothenberg, Sarah E., E-mail: rothenberg.sarah@gmail.com [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Feng Xinbin, E-mail: fengxinbin@vip.skleg.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Li Ping [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China)

    2011-04-15

    Fish consumption is considered the primary pathway for MeHg (MeHg) exposure; however, MeHg exposure also occurs through rice ingestion. Rice is grown in an aquatic environment and although documented MeHg concentrations in rice are lower compared to fish tissue, human exposures exceed international guidelines in some regions where rice is a staple food and rice MeHg levels are elevated. Studies concerning human health exposure to MeHg should also include populations where maternal MeHg exposure occurs through ingestion of rice. Rice does not contain long-chain polyunsaturated fatty acids, which are associated with confounding developmental outcomes in offspring. Rice is also a staple food for more than half the world's population; therefore, it is critical to investigate the potential health risks of maternal ingestion of rice to the developing fetus, the most susceptible population to the deleterious effects of MeHg. Data concerning MeHg in rice are reviewed and micronutrients in rice are discussed. - Research highlights: > Maternal methylmercury exposure through rice may be important. > Rice does not contain the same micronutrients as fish, but may contain methylmercury. > Effects to offspring from methylmercury without beneficial micronutrients are unknown. - Studies concerning maternal methylmercury exposure and cognitive outcomes for offspring should include populations where rice ingestion is the primary methylmercury exposure pathway.

  16. Marker-assisted backcrossing for identification of salt tolerant rice lines

    Directory of Open Access Journals (Sweden)

    M. Moniruzzaman

    2012-12-01

    Full Text Available SSR or microsatellite markers are proved to be ideal for making genetic maps, assisting selection and studying genetic diversity in germplasm. SSR markers are playing important role to identify gene for salt tolerance that can be helpful for plant breeders to develop new cultivars. The experiment was conducted during the period from July 2009 to November 2010 in the experimental field and Biotechnology Laboratory of Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA, Mymensingh to identify salt tolerant rice line of BC1F1 progenies of Binadhan-5 x FL-478 using SSR markers. Salt tolerant genotype, FL-478 was crossed with high yielding variety, Binadhan-5. Randomly selected 40 BC1F1 progenies along with their two parents (Binadhan-5, FL-478 and F1 were genotyped with microsatellite or SSR markers for identification of salt tolerant rice lines. Parental polymorphism survey was assayed by 10 SSR markers and three polymorphic SSR markers viz., RM 336, RM 510, and RM 585 were selected to evaluate BC1F1 rice lines for salt tolerance. In respect of Primer RM 336, 11 lines were found as salt tolerant and 25 lines were heterozygous and 3 lines were susceptible. Primer RM 510 identified two tolerant, 14 heterozygous and 22 susceptible lines. And primer RM 585 identified 4 lines as tolerant and 35 lines as susceptible. Thus, these markers could be efficiently used in tagging salt tolerant genes, in marker-assisted selection and quantitative trait loci (QTL mapping. The selected BC1F1 could be used for developing BC2F1 and BC2F2 and mapping genes for salinity tolerance.

  17. [Spatiotemporal distribution of air temperature and precipitation in rice growth period in Fujian Province of East China and the effects of this distribution on rice planting pattern].

    Science.gov (United States)

    Jiang, Min; Jin, Zhi-Qing; Yang, Hui; Shi, Chun-Lin; Zhu, Chao-Zhi; Lin, Wen-Xiong

    2012-12-01

    In order to investigate the effects of climate change on the rice production and rice planting pattern in Fujian Province, an analysis was made on the spatiotemporal distribution of air temperature and precipitation in rice growth period in the Province, and the possible changes of the local rice planting pattern in the future, based on the A2, B2, and A1 B scenarios of IPCC Special Report on Emission Scenario (SRES). In the future, the rice growth period's air temperature in the Province tended to be increased, and the increment would be increased with time, with the maximum for single cropping rice and being 0.3-2.4 degrees C and 1.5-3.4 degrees C in 2011-2030 and 2031 -2050, respectively. For early rice and late rice, the increment of their growth period's air temperature would be 0.2-0.9 degrees C and 0.7-1.7 degrees C in 2011-2030 and 0.3-2.1 degrees C and 0.5-3.6 degrees C in 2031-2050, respectively, but the annual fluctuation of the mean daily temperature would be most obvious for late rice. The rice growth period's precipitation in most parts of the Province also tended to be increased, and the increment for early rice, single cropping rice, and late rice would be 10%-40%, 10%-30%, and 10%-20%, respectively. The annual fluctuation of the precipitation would be most obvious for the early rice in southeastern Fujian. The elevated air temperature in the future could induce the increase of > or = 10 degrees C accumulated temperature, and lengthen the rice growth season, making it possible to replace early and medium-maturity varieties with late-maturity varieties, and to adopt double-rice planting pattern instead of single-rice planting pattern.

  18. Diversity of Global Rice Markets and the Science Required for Consumer-Targeted Rice Breeding

    Science.gov (United States)

    Calingacion, Mariafe; Laborte, Alice; Nelson, Andrew; Resurreccion, Adoracion; Concepcion, Jeanaflor Crystal; Daygon, Venea Dara; Mumm, Roland; Reinke, Russell; Dipti, Sharifa; Bassinello, Priscila Zaczuk; Manful, John; Sophany, Sakhan; Lara, Karla Cordero; Bao, Jinsong; Xie, Lihong; Loaiza, Katerine; El-hissewy, Ahmad; Gayin, Joseph; Sharma, Neerja; Rajeswari, Sivakami; Manonmani, Swaminathan; Rani, N. Shobha; Kota, Suneetha; Indrasari, Siti Dewi; Habibi, Fatemeh; Hosseini, Maryam; Tavasoli, Fatemeh; Suzuki, Keitaro; Umemoto, Takayuki; Boualaphanh, Chanthkone; Lee, Huei Hong; Hung, Yiu Pang; Ramli, Asfaliza; Aung, Pa Pa; Ahmad, Rauf; Wattoo, Javed Iqbal; Bandonill, Evelyn; Romero, Marissa; Brites, Carla Moita; Hafeel, Roshni; Lur, Huu-Sheng; Cheaupun, Kunya; Jongdee, Supanee; Blanco, Pedro; Bryant, Rolfe; Thi Lang, Nguyen; Hall, Robert D.; Fitzgerald, Melissa

    2014-01-01

    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 the different traits that make up the quality of the rice grain and obtain a full picture of rice quality demographics. Rice is by no means a ‘one size fits all’ crop. Regional preferences are not only striking, they drive the market and hence are of major economic importance in any rice breeding / improvement strategy. In this analysis, we have engaged local experts across the world to perform a full assessment of all the major rice quality trait characteristics and importantly, to determine how these are combined in the most preferred varieties for each of their regions. Physical as well as biochemical characteristics have been monitored and this has resulted in the identification of no less than 18 quality trait combinations. This complexity immediately reveals the extent of the specificity of consumer preference. Nevertheless, further assessment of these combinations at the variety level reveals that several groups still comprise varieties which consumers can readily identify as being different. This emphasises the shortcomings in the current tools we have available to assess rice quality and raises the issue of how we might correct for this in the future. Only with additional tools and research will we be able to define directed strategies for rice breeding which are able to combine important agronomic features with the demands of local consumers for specific quality attributes and hence, design new, improved crop varieties which will be awarded success in the global market. PMID:24454799

  19. Improvement of Salinity Stress Tolerance in Rice: Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Thi My Linh Hoang

    2016-10-01

    Full Text Available Rice (Oryza sativa L. is an important staple crop that feeds more than one half of the world’s population and is the model system for monocotyledonous plants. However, rice is very sensitive to salinity and is the most salt sensitive cereal crop with a threshold of 3 dSm−1 for most cultivated varieties. Despite many attempts using different strategies to improve salinity tolerance in rice, the achievements so far are quite modest. This review aims to discuss challenges that hinder the improvement of salinity stress tolerance in rice as well as potential opportunities for enhancing salinity stress tolerance in this important crop.

  20. Polarizations on abelian varieties

    Science.gov (United States)

    Silverberg, A.; Zarhin, Yu. G.

    2002-09-01

    Every isogeny class over an algebraically closed field contains a principally polarized abelian variety ([10, corollary 1 to theorem 4 in section 23]). Howe ([3]; see also [4]) gave examples of isogeny classes of abelian varieties over finite fields with no principal polarizations (but not with the degrees of all the polarizations divisible by a given non-zero integer, as in Theorem 1·1 below). In [17] we obtained, for all odd primes [script l], isogeny classes of abelian varieties in positive characteristic, all of whose polarizations have degree divisible by [script l]2. We gave results in the more general context of invertible sheaves; see also Theorems 6·1 and 5·2 below. Our results gave the first examples for which all the polarizations of the abelian varieties in an isogeny class have degree divisible by a given prime. Inspired by our results in [17], Howe [5] recently obtained, for all odd primes [script l], examples of isogeny classes of abelian varieties over fields of arbitrary characteristic different from [script l] (including number fields), all of whose polarizations have degree divisible by [script l]2.

  1. Heavy metals in Australian grown and imported rice and vegetables on sale in Australia: health hazard.

    Science.gov (United States)

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

    2014-02-01

    Dietary exposure to heavy metals is a matter of concern for human health risk through the consumption of rice, vegetables and other major foodstuffs. In the present study, we investigated concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) in Australian grown and imported rice and vegetables on sale in Australia. The mean concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn in Australian grown rice were 7.5 µg kg(-1), 21 µg kg(-1), 144 µg kg(-1), 2.9 mg kg(-1), 24.4 mg kg(-1), 166 µg kg(-1), 375 µg kg(-1), and 17.1 mg kg(-1) dry weight (d. wt.), respectively. Except Cd, heavy metal concentrations in Australian grown rice were higher than Bangladeshi rice on sale in Australia. However, the concentrations of Cd, Cr, Cu, and Ni in Indian rice on sale in Australia were higher than Australian grown rice. The concentrations of Cu and Ni in Vietnamese rice, and that of Cd, Cr, Cu, Ni, and Pb in Thai rice on sale in Australia were also higher than Australian grown rice. Heavy metal concentrations in Pakistani rice on sale in Australia were substantially lower than that in Australian grown rice. In Australian grown rice varieties, the concentrations of heavy metals were considerably higher in brown rice varieties than white rice varieties, indicating Australian brown rice as a potential source of dietary heavy metals for Australian consumers. The mean concentrations of heavy metals in Australian grown and Bangladeshi vegetables on sale in Australia were also determined. Some of the Australian grown and Bangladeshi vegetables contained heavy metals higher than Australian standard maximum limits indicating them as potential sources of dietary heavy metals for Australian consumers. Further investigation is required to estimate health risks of heavy metals from rice and vegetables consumption for Australian consumers. © 2013 Published by Elsevier Inc.

  2. Rice DB: an Oryza Information Portal linking annotation, subcellular location, function, expression, regulation, and evolutionary information for rice and Arabidopsis.

    Science.gov (United States)

    Narsai, Reena; Devenish, James; Castleden, Ian; Narsai, Kabir; Xu, Lin; Shou, Huixia; Whelan, James

    2013-12-01

    Omics research in Oryza sativa (rice) relies on the use of multiple databases to obtain different types of information to define gene function. We present Rice DB, an Oryza information portal that is a functional genomics database, linking gene loci to comprehensive annotations, expression data and the subcellular location of encoded proteins. Rice DB has been designed to integrate the direct comparison of rice with Arabidopsis (Arabidopsis thaliana), based on orthology or 'expressology', thus using and combining available information from two pre-eminent plant models. To establish Rice DB, gene identifiers (more than 40 types) and annotations from a variety of sources were compiled, functional information based on large-scale and individual studies was manually collated, hundreds of microarrays were analysed to generate expression annotations, and the occurrences of potential functional regulatory motifs in promoter regions were calculated. A range of computational subcellular localization predictions were also run for all putative proteins encoded in the rice genome, and experimentally confirmed protein localizations have been collated, curated and linked to functional studies in rice. A single search box allows anything from gene identifiers (for rice and/or Arabidopsis), motif sequences, subcellular location, to keyword searches to be entered, with the capability of Boolean searches (such as AND/OR). To demonstrate the utility of Rice DB, several examples are presented including a rice mitochondrial proteome, which draws on a variety of sources for subcellular location data within Rice DB. Comparisons of subcellular location, functional annotations, as well as transcript expression in parallel with Arabidopsis reveals examples of conservation between rice and Arabidopsis, using Rice DB (http://ricedb.plantenergy.uwa.edu.au). © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  3. Complex Algebraic Varieties

    CERN Document Server

    Peternell, Thomas; Schneider, Michael; Schreyer, Frank-Olaf

    1992-01-01

    The Bayreuth meeting on "Complex Algebraic Varieties" focussed on the classification of algebraic varieties and topics such as vector bundles, Hodge theory and hermitian differential geometry. Most of the articles in this volume are closely related to talks given at the conference: all are original, fully refereed research articles. CONTENTS: A. Beauville: Annulation du H(1) pour les fibres en droites plats.- M. Beltrametti, A.J. Sommese, J.A. Wisniewski: Results on varieties with many lines and their applications to adjunction theory.- G. Bohnhorst, H. Spindler: The stability of certain vector bundles on P(n) .- F. Catanese, F. Tovena: Vector bundles, linear systems and extensions of (1).- O. Debarre: Vers uns stratification de l'espace des modules des varietes abeliennes principalement polarisees.- J.P. Demailly: Singular hermitian metrics on positive line bundles.- T. Fujita: On adjoint bundles of ample vector bundles.- Y. Kawamata: Moderate degenerations of algebraic surfaces.- U. Persson: Genus two fibra...

  4. Computing Tropical Varieties

    DEFF Research Database (Denmark)

    Speyer, D.; Jensen, Anders Nedergaard; Bogart, T.

    2005-01-01

    The tropical variety of a d-dimensional prime ideal in a polynomial ring with complex coefficients is a pure d-dimensional polyhedral fan. This fan is shown to be connected in codimension one. We present algorithmic tools for computing the tropical variety, and we discuss our implementation...... of these tools in the Gröbner fan software Gfan. Every ideal is shown to have a finite tropical basis, and a sharp lower bound is given for the size of a tropical basis for an ideal of linear forms....

  5. The Varieties of Ignorance

    DEFF Research Database (Denmark)

    Nottelmann, Nikolaj

    2016-01-01

    This chapter discusses varieties of ignorance divided according to kind (what the subject is ignorant of), degree, and order (e.g. ignorance of ignorance equals second-order ignorance). It provides analyses of notions such as factual ignorance, erotetic ignorance (ignorance of answers to question...

  6. A variety of conditions

    African Journals Online (AJOL)

    This month's CME is comprised of a series of case reports, covering a variety of conditions, including entities such as the little-known Kounis syndrome. The wonderful thing about case reports is that they can be about just about anything. While they are seldom peer reviewed and are certainly not regarded as research, they.

  7. Molecular Evolution of the Rice Blast Resistance Gene Pi-ta in Invasive Weedy Rice in the USA

    Science.gov (United States)

    Lee, Seonghee; Jia, Yulin; Jia, Melissa; Gealy, David R.; Olsen, Kenneth M.; Caicedo, Ana L.

    2011-01-01

    The Pi-ta gene in rice has been effectively used to control rice blast disease caused by Magnaporthe oryzae worldwide. Despite a number of studies that reported the Pi-ta gene in domesticated rice and wild species, little is known about how the Pi-ta gene has evolved in US weedy rice, a major weed of rice. To investigate the genome organization of the Pi-ta gene in weedy rice and its relationship to gene flow between cultivated and weedy rice in the US, we analyzed nucleotide sequence variation at the Pi-ta gene and its surrounding 2 Mb region in 156 weedy, domesticated and wild rice relatives. We found that the region at and around the Pi-ta gene shows very low genetic diversity in US weedy rice. The patterns of molecular diversity in weeds are more similar to cultivated rice (indica and aus), which have never been cultivated in the US, rather than the wild rice species, Oryza rufipogon. In addition, the resistant Pi-ta allele (Pi-ta) found in the majority of US weedy rice belongs to the weedy group strawhull awnless (SH), suggesting a single source of origin for Pi-ta. Weeds with Pi-ta were resistant to two M. oryzae races, IC17 and IB49, except for three accessions, suggesting that component(s) required for the Pi-ta mediated resistance may be missing in these accessions. Signatures of flanking sequences of the Pi-ta gene and SSR markers on chromosome 12 suggest that the susceptible pi-ta allele (pi-ta), not Pi-ta, has been introgressed from cultivated to weedy rice by out-crossing. PMID:22043312

  8. Molecular evolution of the rice blast resistance gene Pi-ta in invasive weedy rice in the USA.

    Directory of Open Access Journals (Sweden)

    Seonghee Lee

    Full Text Available The Pi-ta gene in rice has been effectively used to control rice blast disease caused by Magnaporthe oryzae worldwide. Despite a number of studies that reported the Pi-ta gene in domesticated rice and wild species, little is known about how the Pi-ta gene has evolved in US weedy rice, a major weed of rice. To investigate the genome organization of the Pi-ta gene in weedy rice and its relationship to gene flow between cultivated and weedy rice in the US, we analyzed nucleotide sequence variation at the Pi-ta gene and its surrounding 2 Mb region in 156 weedy, domesticated and wild rice relatives. We found that the region at and around the Pi-ta gene shows very low genetic diversity in US weedy rice. The patterns of molecular diversity in weeds are more similar to cultivated rice (indica and aus, which have never been cultivated in the US, rather than the wild rice species, Oryza rufipogon. In addition, the resistant Pi-ta allele (Pi-ta found in the majority of US weedy rice belongs to the weedy group strawhull awnless (SH, suggesting a single source of origin for Pi-ta. Weeds with Pi-ta were resistant to two M. oryzae races, IC17 and IB49, except for three accessions, suggesting that component(s required for the Pi-ta mediated resistance may be missing in these accessions. Signatures of flanking sequences of the Pi-ta gene and SSR markers on chromosome 12 suggest that the susceptible pi-ta allele (pi-ta, not Pi-ta, has been introgressed from cultivated to weedy rice by out-crossing.

  9. Phylogeography of the Asian rice gall midge Orseolia oryzae (Wood Mason) (Diptera: Cecidomyiidae) in Thailand.

    Science.gov (United States)

    Janique, Solene; Sriratanasak, Wantana; Ketsuwan, Kulchana; Jairin, Jirapong; Jeratthitikul, Ekgachai

    2017-02-01

    The Asian rice gall midge (RGM) Orseolia oryzae (Wood Mason) (Diptera: Cecidomyiidae) is a major pest of rice, leading to yield losses in Thailand and many Asian countries. Despite an increasing number of reported midge outbreaks and the presence of many susceptible rice varieties, only a few studies have focused on the genetic variation of the midges. Therefore, we analyzed the phylogeography among Thai RGM populations covering north, northeast and central Thailand. Two mitochondrial DNA genes, cytochrome C oxidase I (COI) and 12S, and a non-coding repeat region (RR) situated just before COI were amplified. Overall, the haplotype diversity for COI and 12S genes of the Thai population was high, but the nucleotide diversity was quite low. Altogether, the phylogenetic tree and pairwise F st values indicated that Thai RGM populations recently expanded and were homogeneously distributed throughout the country, except for some populations in the north, which most likely became recently isolated from the main population. Two non-coding repeat motifs, that were recently observed in the mitogenome of RGM in India, were absent in Thai populations and replaced by an 89 bp non-coding sequence. Tandem nucleotide repeats of the sequence TA were also observed. The repeat copy number varied from 2 to 11 and was not correlated with geographical repartition of the midge. Finally, COI barcoding divergence between Indian and Thai populations was high (6.3% in average), giving insights into the potential existence of an RGM species complex in Asia.

  10. Genome-wide patterns of nucleotide polymorphism in domesticated rice

    DEFF Research Database (Denmark)

    Caicedo, Ana L; Williamson, Scott H; Hernandez, Ryan D

    2007-01-01

    Domesticated Asian rice (Oryza sativa) is one of the oldest domesticated crop species in the world, having fed more people than any other plant in human history. We report the patterns of DNA sequence variation in rice and its wild ancestor, O. rufipogon, across 111 randomly chosen gene fragments......, and use these to infer the evolutionary dynamics that led to the origins of rice. There is a genome-wide excess of high-frequency derived single nucleotide polymorphisms (SNPs) in O. sativa varieties, a pattern that has not been reported for other crop species. We developed several alternative models...... explanations for patterns of variation in domesticated rice varieties. If selective sweeps are indeed the explanation for the observed nucleotide data of domesticated rice, it suggests that strong selection can leave its imprint on genome-wide polymorphism patterns, contrary to expectations that selection...

  11. Aerobic rice: crop performance and water use efficiency

    Directory of Open Access Journals (Sweden)

    Chiara Grassi

    2011-11-01

    Full Text Available Rice (Oryza sativa production largely depends on traditional flooded rice systems whose sustainability is threatened by a progressive decrease in water availability and a constant increase in rice demand due to strong demographic boom in world population. A newly developed water-saving rice system is aerobic rice in which rice grows in nonflooded and unsaturated soil. From 2001, at the International Rice Research Institute in the Philippines, this system has been monitored to identify potentially promising varieties of rice able to grow as an irrigated upland crop and quantify yield potential and water use efficiency. This study reports on the results of cultivating the upland rice variety Apo under different water conditions in 2004-2005 at the IRRI farm in both the dry and wet seasons. The water treatments considered were: aerobic and flooded conditions, alternated flooded and aerobic conditions and aerobic after fallow. Yield and water productivity were compared between aerobic and flooded treatment in both seasons, with the objective of analysing the differences between water treatments. In the experiment the effect of different nitrogen (N application is also considered. The results indicate that the aerobic rice yield was lower than rice production under flood treatment, confirming that observed over past years. Nevertheless, when the aerobic condition is alternated with the anaerobic condition, or a fallow period, the production under aerobic treatment provides good yields (respectively 4.2 and 4.4 ha-1. The fallow period was introduced to observe the response of rice grown under this management. Water productivity was higher in aerobic fields, especially after fallow (0.88 g kg-1. The nitrogen application induced an increase in yield and water productivity, partially compensating for the lack of water in aerobic fields.

  12. Quiver Varieties and Branching

    Directory of Open Access Journals (Sweden)

    Hiraku Nakajima

    2009-01-01

    Full Text Available Braverman and Finkelberg recently proposed the geometric Satake correspondence for the affine Kac-Moody group Gaff [Braverman A., Finkelberg M., arXiv:0711.2083]. They conjecture that intersection cohomology sheaves on the Uhlenbeck compactification of the framed moduli space of Gcpt-instantons on $R^4/Z_r$ correspond to weight spaces of representations of the Langlands dual group $G_{aff}^{vee}$ at level $r$. When $G = SL(l$, the Uhlenbeck compactification is the quiver variety of type $sl(r_{aff}$, and their conjecture follows from the author's earlier result and I. Frenkel's level-rank duality. They further introduce a convolution diagram which conjecturally gives the tensor product multiplicity [Braverman A., Finkelberg M., Private communication, 2008]. In this paper, we develop the theory for the branching in quiver varieties and check this conjecture for $G = SL(l$.

  13. Varieties of lattices

    CERN Document Server

    Jipsen, Peter

    1992-01-01

    The study of lattice varieties is a field that has experienced rapid growth in the last 30 years, but many of the interesting and deep results discovered in that period have so far only appeared in research papers. The aim of this monograph is to present the main results about modular and nonmodular varieties, equational bases and the amalgamation property in a uniform way. The first chapter covers preliminaries that make the material accessible to anyone who has had an introductory course in universal algebra. Each subsequent chapter begins with a short historical introduction which sites the original references and then presents the results with complete proofs (in nearly all cases). Numerous diagrams illustrate the beauty of lattice theory and aid in the visualization of many proofs. An extensive index and bibliography also make the monograph a useful reference work.

  14. VARIETIES OF VIOLENT BEHAVOR.

    Science.gov (United States)

    Widom, Cathy Spatz

    2014-08-01

    There is an implicit assumption of homogeneity across violent behaviors and offenders in the criminology literature. Arguing against this assumption, I draw on three distinct literatures [child abuse and neglect (CAN) and violence, violence and post-traumatic stress disorder (PTSD), and CAN and PTSD] to provide a rationale for an examination of varieties of violent behaviors. I use data from my prospective cohort design study of the long-term consequences of CAN to define three varieties of violent offenders using age of documented cases of CAN, onset of PTSD, and first violent arrest in a temporally correct manner [CAN → to violence, CAN → PTSD → violence (PTSD first), and CAN → violence → PTSD (violence first)], and a fourth variety, violence only. The results illustrate meaningful heterogeneity in violent behavior and different developmental patterns and characteristics. There are three major implications: First, programs and policies that target violence need to recognize the heterogeneity and move away from a "one-size-fits-all" approach. Second, violence prevention policies and programs that target abused and neglected children are warranted, given the prominent role of CAN in the backgrounds of these violent offenders. Third, criminologists and others interested in violence need to attend to the role of PTSD, which is present in about one fifth (21 percent) of these violent offenders, and not relegate the study of these offenders to the psychiatric and psychological literatures.

  15. VARIETIES OF VIOLENT BEHAVOR*

    Science.gov (United States)

    WIDOM, CATHY SPATZ

    2014-01-01

    There is an implicit assumption of homogeneity across violent behaviors and offenders in the criminology literature. Arguing against this assumption, I draw on three distinct literatures [child abuse and neglect (CAN) and violence, violence and post-traumatic stress disorder (PTSD), and CAN and PTSD] to provide a rationale for an examination of varieties of violent behaviors. I use data from my prospective cohort design study of the long-term consequences of CAN to define three varieties of violent offenders using age of documented cases of CAN, onset of PTSD, and first violent arrest in a temporally correct manner [CAN → to violence, CAN → PTSD → violence (PTSD first), and CAN → violence → PTSD (violence first)], and a fourth variety, violence only. The results illustrate meaningful heterogeneity in violent behavior and different developmental patterns and characteristics. There are three major implications: First, programs and policies that target violence need to recognize the heterogeneity and move away from a “one-size-fits-all” approach. Second, violence prevention policies and programs that target abused and neglected children are warranted, given the prominent role of CAN in the backgrounds of these violent offenders. Third, criminologists and others interested in violence need to attend to the role of PTSD, which is present in about one fifth (21 percent) of these violent offenders, and not relegate the study of these offenders to the psychiatric and psychological literatures. PMID:25505799

  16. Organogenesis induction in rice callus by cyanobacterial ...

    African Journals Online (AJOL)

    The endosperm of three rice varieties, IR 50, ASD 16 and ADT 36, were used as explants. IR 50 showed earlier and good callus induction response in MS medium. For root induction, cyanobaterial extracellular product was added instead of 2,4-D. The result showed that the number of days taken for root initiation and root ...

  17. Indica rice genome assembly, annotation and mining of blast disease resistance genes.

    Science.gov (United States)

    Mahesh, H B; Shirke, Meghana Deepak; Singh, Siddarth; Rajamani, Anantharamanan; Hittalmani, Shailaja; Wang, Guo-Liang; Gowda, Malali

    2016-03-16

    Rice is a major staple food crop in the world. Over 80% of rice cultivation area is under indica rice. Currently, genomic resources are lacking for indica as compared to japonica rice. In this study, we generated deep-sequencing data (Illumina and Pacific Biosciences sequencing) for one of the indica rice cultivars, HR-12 from India. We assembled over 86% (389 Mb) of rice genome and annotated 56,284 protein-coding genes from HR-12 genome using Illumina and PacBio sequencing. Comprehensive comparative analyses between indica and japonica subspecies genomes revealed a large number of indica specific variants including SSRs, SNPs and InDels. To mine disease resistance genes, we sequenced few indica rice cultivars that are reported to be highly resistant (Tetep and Tadukan) and susceptible (HR-12 and Co-39) against blast fungal isolates in many countries including India. Whole genome sequencing of rice genotypes revealed high rate of mutations in defense related genes (NB-ARC, LRR and PK domains) in resistant cultivars as compared to susceptible. This study has identified R-genes Pi-ta and Pi54 from durable indica resistant cultivars; Tetep and Tadukan, which can be used in marker assisted selection in rice breeding program. This is the first report of whole genome sequencing approach to characterize Indian rice germplasm. The genomic resources from our work will have a greater impact in understanding global rice diversity, genetics and molecular breeding.

  18. IDENTIFICATION OF A MAJOR QUANTITATIVE TRAIT LOCUS CONFERRING RICE BLAST RESISTANCE USING RECOMBINANT INBRED LINES

    Directory of Open Access Journals (Sweden)

    Sobrizal Sobrizal

    2013-05-01

    Full Text Available Blast disease caused by Pyricularia oryzae is one of the limiting factors for rice production world wide. The use of resistant varieties for managing blast disease is considered as the most eco-friendly approaches. However, their resistances may be broken down within a few years due to the appearance of new virulent blast races in the field. The objective of the present study was to identify the quantitative trait locus (QTL conferring resistance to blast disease using 126 recombinant inbred (RI lines originated from a crossing of a durably resistant upland rice genotype (Laka and a highly susceptible rice accession cultivar (Kencana Bali. The RI population was developed through a single seed descent method from 1997 to 2004. Resistance of the RI lines was evaluated for blast in an endemic area of Sukabumi, West Java, in 2005. Disease intensity of the blast was examined following the standard evaluation system developed by the International Rice Research Institute (IRRI. At the same year the RI lines were analyzed with 134 DNA markers. Results of the study showed that one major QTL was found to be associated with blast resistance, and this QTL was located near RM2136 marker on the long arm of chromosome 11. This QTL explained 87% of the phenotypic variation with 37% additive effect. The map position of this QTL differed from that of a partial resistant gene, Pi34, identified previously on chromosome 11 in the Japanese durably resistant variety, Chubu 32. The QTL, however, was almost at the same position as that of the multiple allele-resistant gene, Pik. Therefore, an allelic test should be conducted to clarify the allelic relationship between QTL identified in this study and the Pik. The RI lines are the permanent segregating population that could be very useful for analysing phenotypic variations of important agronomic traits possibly owned by the RI lines. The major QTL identified in this study could be used as a genetic resource in

  19. Rice peasants and rice research in Colombia

    NARCIS (Netherlands)

    Spijkers, P.A.N.M.

    1983-01-01

    Rice has been grown as a food crop in Latin America from early colonial times. In Colombia rice became a prominent subsistence crop especially on the north coast where it has been grown since the 17th century, sometimes also as a commercial crop. During the last twenty years there has been a sharp

  20. Modeling the rice phenology and production in China with SIMRIW: sensitivity analysis and parameter estimation

    Science.gov (United States)

    Zhang, Shuai; Tao, Fulu; Shi, Runhe

    2014-12-01

    Crop models are robust tools for simulating the impact of climate change on rice development and production, but are usually designed for specific stations and varieties. This study focuses on a more adaptable model called Simulation Model for Rice-Weather Relations (SIMRIW). The model was calibrated and validated in major rice production regions over China, and the parameters that most affect the model's output were determined in sensitivity analyses. These sensitive parameters were estimated in different ecological zones. The simulated results of single and double rice cropping systems in different ecological zones were then compared. The accuracy of SIMRIW was found to depend on a few crucial parameters. Using optimized parameters, SIMRIW properly simulated the rice phenology and yield in single and double cropping systems in different ecological zones. Some of the parameters were largely dependent on ecological zone and rice type, and may reflect the different climate conditions and rice varieties among ecological zones.

  1. Stamena winter wheat variety

    Directory of Open Access Journals (Sweden)

    Mišić Todor

    2001-01-01

    Full Text Available Stamena is a winter wheat variety developed at the Institute of Field and Vegetable Crops in Novi Sad, Yugoslavia. It was released by the Federal Commission for varietals Approval in 1999. Stamena was developed by crossing genetically divergent and highly productive parents Lasta and Rodna (Breeders: T. Mišić. N. Mladenov, Z. Jerković and R. Jevtić. Spike is white, smooth, awn less, medium compact with 18-21 spike lets. The grain is vitreous and dark red (Triticum aestivum L. ssp. vulgar e var. lutescens. Stamena is a medium early variety, 1 day earlier than Partizanka and 3 days earlier than Jugoslavija (Table 4. It has excellent resistance to winterkilling, as in very winter hardy Partizanka. The average stem height is 78 cm, with a good resistance to lodging. Stamena has field resistance to leaf rust (Pucce, recondita tritict, horizontal resistance, which is the type of resistance that modern wheat breeding is interested in. The resistance to stem rust (Pucce, graminis tritict is good and to powdery mildew (Erysiphegraminis tritici very good. The 1000 grain mass is about 32 g and volume grain mass 81.3 kg/hi. (Table 2. Stamena is classified in the subgroup A-l. It has excellent milling and baking quality and it belong to the 1st technological group (quality enhancer. The quantity of dry gluten is about 9%. The variety Stamena is a very productive, with the genetic potential for grain above 11 t/ha suitable for growing on fertile and less fertile soils. It has started to be grown commercially in 2000.

  2. Paleogenomic Analysis of the Short Arm of Chromosome 3 Reveals the History of the African and Asian Progenitors of Cultivated Rices

    OpenAIRE

    Roulin, Anne; Chaparro, Cristian; Pi?gu, Benoit; Jackson, Scott; Panaud, Olivier

    2010-01-01

    Rice is one of the most important crops, feeding more than half of the world population. There are two cultivated species, the African rice Oryza glaberrima and the Asian rice O. sativa. Although the African species is gradually replaced by O. sativa in most of African rice agrosystems, this species represents an important reservoir of genes of agronomical interest. Their exploitation for the development of modern African rice varieties requires a good understanding of the genetic relationshi...

  3. Effect of Stewing in Cooking Step on Textural and Morphological Properties of Cooked Rice

    Directory of Open Access Journals (Sweden)

    E. GHASEMI

    2009-09-01

    Full Text Available Stewing of rice grains by steam after boiling in excess water can be used for cooking rice perfectly. The effects of this procedure in cooking of three varieties of Iranian rice (Sang Tarom, Domsiyah and Fajr on textural and morphological properties of cooked rice grains were investigated. The results showed that this step in rice cooking reduced the hardness and increased the adhesiveness of rice grains significantly. By the use of the scanning electron microscopy, it was shown that the outer surface of cooked rice stewed by steam had less porosity and closer pores due to the modification during cooking, and better gelatinization and more expansion of starch granules compared to non-stewed samples. The use of this procedure in rice cooking to provide a fully cooked and gelatinized, softer and stickier final product is recommended.

  4. Fine mapping of RYMV3: a new resistance gene to Rice yellow mottle virus from Oryza glaberrima.

    Science.gov (United States)

    Pidon, Hélène; Ghesquière, Alain; Chéron, Sophie; Issaka, Souley; Hébrard, Eugénie; Sabot, François; Kolade, Olufisayo; Silué, Drissa; Albar, Laurence

    2017-04-01

    A new resistance gene against Rice yellow mottle virus was identified and mapped in a 15-kb interval. The best candidate is a CC-NBS-LRR gene. Rice yellow mottle virus (RYMV) disease is a serious constraint to the cultivation of rice in Africa and selection for resistance is considered to be the most effective management strategy. The aim of this study was to characterize the resistance of Tog5307, a highly resistant accession belonging to the African cultivated rice species (Oryza glaberrima), that has none of the previously identified resistance genes to RYMV. The specificity of Tog5307 resistance was analyzed using 18 RYMV isolates. While three of them were able to infect Tog5307 very rapidly, resistance against the others was effective despite infection events attributed to resistance-breakdown or incomplete penetrance of the resistance. Segregation of resistance in an interspecific backcross population derived from a cross between Tog5307 and the susceptible Oryza sativa variety IR64 showed that resistance is dominant and is controlled by a single gene, named RYMV3. RYMV3 was mapped in an approximately 15-kb interval in which two candidate genes, coding for a putative transmembrane protein and a CC-NBS-LRR domain-containing protein, were annotated. Sequencing revealed non-synonymous polymorphisms between Tog5307 and the O. glaberrima susceptible accession CG14 in both candidate genes. An additional resistant O. glaberrima accession, Tog5672, was found to have the Tog5307 genotype for the CC-NBS-LRR gene but not for the putative transmembrane protein gene. Analysis of the cosegregation of Tog5672 resistance with the RYMV3 locus suggests that RYMV3 is also involved in Tog5672 resistance, thereby supporting the CC-NBS-LRR gene as the best candidate for RYMV3.

  5. Effects of cooking methods and starch structures on starch hydrolysis rates of rice.

    Science.gov (United States)

    Reed, Michael O; Ai, Yongfeng; Leutcher, Josh L; Jane, Jay-lin

    2013-07-01

    This study aimed to understand effects of different cooking methods, including steamed, pilaf, and traditional stir-fried, on starch hydrolysis rates of rice. Rice grains of 3 varieties, japonica, indica, and waxy, were used for the study. Rice starch was isolated from the grain and characterized. Amylose contents of starches from japonica, indica, and waxy rice were 13.5%, 18.0%, and 0.9%, respectively. The onset gelatinization temperature of indica starch (71.6 °C) was higher than that of the japonica and waxy starch (56.0 and 56.8 °C, respectively). The difference was attributed to longer amylopectin branch chains of the indica starch. Starch hydrolysis rates and resistant starch (RS) contents of the rice varieties differed after they were cooked using different methods. Stir-fried rice displayed the least starch hydrolysis rate followed by pilaf rice and steamed rice for each rice variety. RS contents of freshly steamed japonica, indica, and waxy rice were 0.7%, 6.6%, and 1.3%, respectively; those of rice pilaf were 12.1%, 13.2%, and 3.4%, respectively; and the stir-fried rice displayed the largest RS contents of 15.8%, 16.6%, and 12.1%, respectively. Mechanisms of the large RS contents of the stir-fried rice were studied. With the least starch hydrolysis rate and the largest RS content, stir-fried rice would be a desirable way of preparing rice for food to reduce postprandial blood glucose and insulin responses and to improve colon health of humans. © 2013 Institute of Food Technologists®

  6. PDH45 transgenic rice maintain cell viability through lower accumulation of Na(+), ROS and calcium homeostasis in roots under salinity stress.

    Science.gov (United States)

    Nath, Manoj; Yadav, Sandep; Kumar Sahoo, Ranjan; Passricha, Nishat; Tuteja, Renu; Tuteja, Narendra

    2016-02-01

    Salinity severely affects the growth/productivity of rice, which is utilized as major staple food crop worldwide. PDH45 (pea DNA helicase 45), a member of the DEAD-box helicase family, actively provides salinity stress tolerance, but the mechanism behind this is not well known. Therefore, in order to understand the mechanism of stress tolerance, sodium ion (Na(+)), reactive oxygen species (ROS), cytosolic calcium [Ca(2+)]cyt and cell viability were analyzed in roots of PDH45 transgenic-IR64 rice lines along with wild-type (WT) IR64 rice under salinity stress (100mM and 200 mM NaCl). In addition, the roots of salinity-tolerant (FL478) and susceptible (Pusa-44) rice varieties were also analyzed under salinity stress for comparative analysis. The results reveal that, under salinity stress (100mM and 200 mM NaCl), roots of PDH45 transgenic lines accumulate lower levels of Na(+), ROS and maintain [Ca(2+)]cyt and exhibit higher cell viability as compared with roots of WT (IR64) plants. Similar results were also obtained in the salinity-tolerant FL478 rice. However, the roots of WT and salinity-susceptible Pusa-44 rice accumulated higher levels of Na(+), ROS and [Ca(2+)]cyt imbalance and lower cell viability during salinity stress, which is in contrast to the overexpressing PDH45 transgenic lines and salinity-tolerant FL478 rice. Further, to understand the mechanism of PDH45 at molecular level, comparative expression profiling of 12 cation transporters/genes was also conducted in roots of WT (IR64) and overexpressing PDH45 transgenic lines (L1 and L2) under salt stress (24h of 200 mM NaCl). The expression analysis results show altered and differential gene expression of cation transporters/genes in salt-stressed roots of WT (IR64) and overexpressing transgenic lines (L1 and L2). These observations collectively suggest that, under salinity stress conditions, PDH45 is involved in the regulation of Na(+) level, ROS production, [Ca(2+)]cyt homeostasis, cell viability and

  7. agronomic performance of introduced banana varieties in lowlands ...

    African Journals Online (AJOL)

    jen

    Most of Rwandan banana cultivars are low-yielding and susceptible to pests and diseases. High yielding and pest/disease resistant varieties have been obtained in advanced breeding centers recently. Introduction, evaluation and adoption of such varieties by local producers may be one of the options to boost yields.

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

    OpenAIRE

    Saleh, Mohammed; Meullenet, Jean-Francois

    2013-01-01

    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....

  9. Proteomic Analysis of Rice Seedlings Under Cold Stress.

    Science.gov (United States)

    Ji, Li; Zhou, Ping; Zhu, Ya; Liu, Fang; Li, Rongbai; Qiu, Yongfu

    2017-08-01

    Low temperature can greatly restrict the growth and development of rice. The rice seedlings show growth retardation, lamina wrap, and part of blade even died under the condition of low temperature. In order to get more information about cold stress responses in rice, two dimensional electrophoresis and bioinformatics analysis of mass spectrometry were used to preliminary survey the cold tolerance of cold sensitive line 9311 and cold resistance variety Fujisaka 5 under cold stress. Two dimensional electrophoresis maps of 9311 and Fujisaka 5 were established under cold treatment. With analysis of bioinformation, the proteins were found involve in many aspects of rice development. The largest category of proteins is functioning on metabolism. By comparing the proteins from the two varieties, it can be found that most proteins from 9311 were down-regulated and were up-regulated in Fujisaka 5. The results showed that the membrane composition and structure were damaged, metabolism changed dramatically and rice defense system was activated under the cold stimulation. Fifty-nine proteins related to the resistance of cold stress were identified in our study, and we have investigated and classified all of their biological functions. The importance of our study are providing some conduct for the research of rice resistant to cold stress, supporting auxiliary technique for rice varieties and widening the search field of cold tolerance in plants.

  10. Varieties of online gatekeeping

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Kleis

    organizations as gatekeepers shaping our political information environments. Political communication scholars have traditionally focused on the role of journalists and news media as gatekeepers (see e.g. Livingston and Bennett, 2003; Shoemaker et al, 2009). But a growing number of researchers (e.g. Barzilai...... in different ways and for different purposes. The three varieties are (1) editorially-based gatekeeping processes (typically defining what information is displayed as news on news media websites), (2) link-based gatekeeping processes (the core of how search engines like Google select what information...... Google and Facebook) have in less than a decade come to rival news media websites in importance as gateways to news across all the seven countries covered, with potentially profound consequences for our digital political information environments....

  11. Introduction to Abelian varieties

    CERN Document Server

    Murty, V Kumar

    1993-01-01

    The book represents an introduction to the theory of abelian varieties with a view to arithmetic. The aim is to introduce some of the basics of the theory as well as some recent arithmetic applications to graduate students and researchers in other fields. The first part contains proofs of the Abel-Jacobi theorem, Riemann's relations and the Lefschetz theorem on projective embeddings over the complex numbers in the spirit of S. Lang's book Introduction to algebraic and abelian functions. Then the Jacobians of Fermat curves as well as some modular curves are discussed. Finally, as an application, Faltings' proof of the Mordell conjecture and its intermediate steps, the Tate conjecture and the Shafarevich conjecture, are sketched. - H. Lange for MathSciNet.

  12. Susceptibilidade de lagartas dos biótipos milho e arroz de Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera: Noctuidae a inseticidas com diferentes modos de ação Susceptibility of caterpillars of the biotypes corn and rice of Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera: Noctuidae to insecticides with different action manners

    Directory of Open Access Journals (Sweden)

    Gustavo Rossato Busato

    2006-02-01

    Full Text Available O objetivo do trabalho foi avaliar a susceptibilidade de lagartas dos biótipos milho e arroz de Spodoptera frugiperda, a inseticidas com diferentes modos de ação. Os insetos foram coletados em milho e em arroz irrigado no agroecossistema de várzea, município de Pelotas, região que produz milho e arroz irrigado (lado a lado. Os experimentos foram realizados, em condições controladas de temperatura (25 ± 1°C, umidade relativa (70 ± 10% e fotofase (14 horas, utilizando-se folhas do híbrido de milho Pionner 30F33 (40 dias após a emergência. As folhas pulverizadas em torre de Potter calibrada para aplicação de um volume de calda de 1,7 ± 0,305mg cm-2, foram colocadas em recipientes de plásticos com tampa, sendo individualizadas 25 lagartas de 3° ínstar de cada biótipo de S. frugiperda. Os inseticidas e concentrações avaliados foram: clorpirifós [Lorsban 480 BR, 0,960g i.a. L-1 (Organofosforado], lambda-cialotrina [Karate Zeon 50 CE, 0,003g i.a. L-1 (Piretróide sintético], lufenuron [Match CE, 0,006g i.a. L-1 (Aciluréia], methoxifenozide [Intrepid 240 SC, 0,158g i.a. L-1 (Diacilhidrazina] e spinosad [Tracer, 0,960g i.a. L-1 (Naturalyte]. A avaliação da mortalidade foi realizada 24, 48, 72, 96 e 120 horas após o tratamento. O biótipo milho de S. frugiperda foi menos suscetível aos inseticidas lambda-cialotrina, lufenuron e methoxifenozide. Os inseticidas clorpirifós e spinosad foram eficientes no controle das lagartas dos biótipos milho e arroz de S. frugiperda.The objective of this work was to evaluate the susceptibility of caterpillars of the biotypes corn and rice of Spodoptera frugiperda, to insecticides with different action manners. The insects were collected in corn and in irrigated rice in the lowland, county of Pelotas, area that produces corn and irrigated rice (side by side. The experiments were conducted, in controlled conditions of temperature (25 ± 1°C, relative humidity (70 ± 10% and photophase (14

  13. Mode of gene action of inheritance for resistance to rice yellow ...

    African Journals Online (AJOL)

    Rice (Oryza glaberrima) yellow mottle virus (RYMV) causes significant economic damage to rainfed and lowland irrigated rice, Oryza sativa L. in West and East Africa. This study investigated the mode of gene action of resistance to RYMV using generation mean analysis. Crosses were made between a more susceptible ...

  14. Isozyme Analysis on Different Varieties of Sugarcane

    Directory of Open Access Journals (Sweden)

    Johnson M.

    2012-05-01

    Full Text Available Isozymic and protein diversity among five sugarcane varieties viz., Co 6304, Co 85019, Co 8371, Co 89003 and Co 91010 were studied to understand the varietal interrelationship and to identify the biochemical marker for the disease resistance and stress tolerance. The standard technique of vertical gel electrophoresis PAGE was employed for size separation of isozymes. The gel was stained with different staining solutions for different isozyme systems viz. peroxidase, esterase, acid phosphatase, alkaline phosphatase and proteins. Rf values of the banding profiles, similarity index and variation between the varieties were analysed. Among the four enzyme systems, peroxidase profile reveals the difference between the disease resistant / susceptible and abiotic stress tolerant / non tolerant varieties. The two isoperoxidase bands with Rf values 0.62 and 0.66 showed their presence in disease resistant and abiotic tolerant varieties. The presence of two marker bands (0.62, 0.66 of resistant and stress tolerant varieties suggest that the variety Co 6304 may also be resistant to smut, wilt and moderately resistant to red rot and tolerant to drought.

  15. Molecular and Biochemical Analysis of Two Rice Flavonoid 3'-Hydroxylase to Evaluate Their Roles in Flavonoid Biosynthesis in Rice Grain.

    Science.gov (United States)

    Park, Sangkyu; Choi, Min Ji; Lee, Jong Yeol; Kim, Jae Kwang; Ha, Sun-Hwa; Lim, Sun-Hyung

    2016-09-13

    Anthocyanins and proanthocyanidins, the major flavonoids in black and red rice grains, respectively, are mainly derived from 3',4'-dihydroxylated leucocyanidin. 3'-Hydroxylation of flavonoids in rice is catalyzed by flavonoid 3'-hydroxylase (F3'H: EC 1.14.13.21). We isolated cDNA clones of the two rice F3'H genes (CYP75B3 and CYP75B4) from Korean varieties of white, black, and red rice. Sequence analysis revealed allelic variants of each gene containing one or two amino acid substitutions. Heterologous expression in yeast demonstrated that CYP75B3 preferred kaempferol to other substrates, and had a low preference for dihydrokaempferol. CYP75B4 exhibited a higher preference for apigenin than for other substrates. CYP75B3 from black rice showed an approximately two-fold increase in catalytic efficiencies for naringenin and dihydrokaempferol compared to CYP75B3s from white and red rice. The F3'H activity of CYP75B3 was much higher than that of CYP75B4. Gene expression analysis showed that CYP75B3, CYP75B4, and most other flavonoid pathway genes were predominantly expressed in the developing seeds of black rice, but not in those of white and red rice, which is consistent with the pigmentation patterns of the seeds. The expression levels of CYP75B4 were relatively higher than those of CYP75B3 in the developing seeds, leaves, and roots of white rice.

  16. Evaluation of strawberry varieties in hydroponics systems in greenhouses

    OpenAIRE

    Costaz, E; Leal, PM

    2008-01-01

    Experiments were accomplished in the experimental field of the Faculty of Agricultural Engineering at State University of Campinas (Unicamp). Four varieties of strawberry were tested (Campinas, Seascape, Sweet Charlie and Tudla) in four hydroponics production systems (100mm and 150mm channels and 150mm channel with a vase containing coconut fiber and a vertical pipe containing carbonized rice skin) in three greenhouses with different technical: i) greenhouse without air evaporative cooling no...

  17. Rational points on varieties

    CERN Document Server

    Poonen, Bjorn

    2017-01-01

    This book is motivated by the problem of determining the set of rational points on a variety, but its true goal is to equip readers with a broad range of tools essential for current research in algebraic geometry and number theory. The book is unconventional in that it provides concise accounts of many topics instead of a comprehensive account of just one-this is intentionally designed to bring readers up to speed rapidly. Among the topics included are Brauer groups, faithfully flat descent, algebraic groups, torsors, étale and fppf cohomology, the Weil conjectures, and the Brauer-Manin and descent obstructions. A final chapter applies all these to study the arithmetic of surfaces. The down-to-earth explanations and the over 100 exercises make the book suitable for use as a graduate-level textbook, but even experts will appreciate having a single source covering many aspects of geometry over an unrestricted ground field and containing some material that cannot be found elsewhere. The origins of arithmetic (o...

  18. "Tinni" Rice ( Oryza rufipogon Griff.) Production: An Integrated Sociocultural Agroecosystem in Eastern Uttar Pradesh of India

    Science.gov (United States)

    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.

  19. Rice (Oryza hemoglobins [v2; ref status: indexed, http://f1000r.es/4vp

    Directory of Open Access Journals (Sweden)

    Raúl Arredondo-Peter

    2014-12-01

    Full Text Available 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 O2, whereas rice Hb5 and tHb possibly exhibit a low to moderate affinity for O2. 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 O2-transport, O2-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.

  20. Determine quality of rice seed using rapid techniques

    Science.gov (United States)

    Cheng, Fang; Zheng, Siyuan; Ying, Yibin

    2007-09-01

    This paper is aimed at investigating the possibility of sorting rice seeds by rapid techniques. Machine vision and dielectric separation were involved to determine external and internal quality of rice seeds. A conceptual rapid seed sorter is proposed. Two varieties of rice seeds planted and harvested in different years were involved in the experiments. Using morphological and color features gave a highly acceptable classification of normal and defective seeds. Dielectric parameters can be used to classify rice seeds into high vigor and low vigor. Combination of appearance characteristics and dielectric properties provide comprehensive response of seed quality. A highly acceptable defects classification and vigor improvement were achieved when the principle prototype was implemented for all the samples to test the adaptability. The good adaptability of machine vision and dielectric separation indicate the potential to determine quality of rice seeds rapidly. This paper presents the significant elements of the conceptual prototype and emphasizes the important aspects of the image processing and dielectric separation techniques.

  1. Phosphorus and Iron Deficiencies Influences Rice Shoot Growth in an Oxygen Dependent Manner: Insight from Upland and Lowland Rice.

    Science.gov (United States)

    Mongon, Jenjira; Chaiwong, Nanthana; Bouain, Nadia; Prom-U-Thai, Chanakan; Secco, David; Rouached, Hatem

    2017-03-10

    Rice is the main staple crop for one-third of the world population. To maximize yields, large quantities and constant input of fertilizers containing essential nutrients such as phosphorus (P) and iron (Fe) are added. Rice can germinate in both aerobic and anaerobic conditions, but the crosstalk between oxygen (O₂) and nutrients such as P and Fe on plant growth remains obscure. The aim of this work was to test whether such interactions exist, and, if so, if they are conserved between up- and lowland rice varieties. To do so, we assessed shoot and root biomass as well as inorganic phosphate (Pi) accumulation in four rice varieties, including two lowland rice varieties Nipponbare and Suphanburi 1 (SPR1) (adapted to non-aerated condition) and two upland rice varieties CMU122 and Sew Mae Jun (SMJ) (adapted to aerated condition) under various conditions of Pi and/or Fe deficiencies, in aerated and non-areated solution. Under these different experimental conditions, our results revealed that the altered shoot biomass in Nipponbare and SPR1 was O₂-dependent but to a lesser extent in CMU122 and SMJ cultivars. In this perspective, discovering the biological significance and molecular basis of these mineral elements and O₂ signal interaction is needed to fully appreciate the performance of plants to multiple environmental changes.

  2. Evaluation of Rice Resistance to Southern Rice Black-Streaked Dwarf Virus and Rice Ragged Stunt Virus through Combined Field Tests, Quantitative Real-Time PCR, and Proteome Analysis.

    Science.gov (United States)

    Wang, Zhenchao; Yu, Lu; Jin, Linhong; Wang, Wenli; Zhao, Qi; Ran, Longlu; Li, Xiangyang; Chen, Zhuo; Guo, Rong; Wei, Yongtian; Yang, Zhongcheng; Liu, Enlong; Hu, Deyu; Song, Baoan

    2017-02-22

    Diseases caused by southern rice black-streaked dwarf virus (SRBSDV) and rice ragged stunt virus (RRSV) considerably decrease grain yield. Therefore, determining rice cultivars with high resistance to SRBSDV and RRSV is necessary. In this study, rice cultivars with high resistance to SRBSDV and RRSV were evaluated through field trials in Shidian and Mangshi county, Yunnan province, China. SYBR Green I-based quantitative real-time polymerase chain reaction (qRT-PCR) analysis was used to quantitatively detect virus gene expression levels in different rice varieties. The following parameters were applied to evaluate rice resistance: acre yield (A.Y.), incidence of infected plants (I.I.P.), virus load (V.L.), disease index (D.I.), and insect quantity (I.Q.) per 100 clusters. Zhongzheyou1 (Z1) and Liangyou2186 (L2186) were considered the most suitable varieties with integrated higher A.Y., lower I.I.P., V.L., D.I. and I.Q. In order to investigate the mechanism of rice resistance, comparative label-free shotgun liquid chromatography tandem-mass spectrometry (LC-MS/MS) proteomic approaches were applied to comprehensively describe the proteomics of rice varieties' SRBSDV tolerance. Systemic acquired resistance (SAR)-related proteins in Z1 and L2186 may result in the superior resistance of these varieties compared with Fengyouxiangzhan (FYXZ).

  3. Developed Maize Varieties in Nigeria.

    African Journals Online (AJOL)

    In Nigeria, the most important cereals are sorghum, millet, rice, maize and wheat (Wudiri, 1999). Of all these cereals, maize. remains the most popularly grown and consumed in all- ecological zones of the country. I. The major chemical constituent of the maize kernel is carbohydrate which accounts for 72-73% of the Kernel.

  4. Molecular profiling of an interspecific rice population derived from a ...

    African Journals Online (AJOL)

    NERICA rices are interspecific inbred progeny derived from crosses between Oryza sativa x O. glaberrima. In this study, we evaluated 70 BC2 interspecific lines, developed by crossing a tropical japonica variety (WAB 56-104) as the recurrent parent to an O. glaberrima variety (CG 14) as the donor parent, followed by the ...

  5. Molecular profiling of interspecific lowland rice populations derived ...

    African Journals Online (AJOL)

    Several lowland NERICAs (New Rice for Africa) were derived from crosses between IR64 (an Oryza sativa subsp. indica variety) and Tog5681 (an Oryza glaberrima variety) that possess useful traits adapted to lowland conditions in West Africa. The proportion of parental genomic contribution and extent of genetic ...

  6. Some Physco-thermal properties of Rice Bran | Obetta | Global ...

    African Journals Online (AJOL)

    Some of these properties were combined for study on their effect on thermal conductivity which was one of the thermal properties studied. Mean values of the thermal conductivity determined ranged from 0.2456 to 0.5764 W/m oC depending on the moisture content of the raw rice bran and the variety. The two major varieties ...

  7. Efficacy of rice husk ash against rice weevil and lesser grain borer ...

    African Journals Online (AJOL)

    The objective of this study was to determine efficacy of RHA from “Mr. Harry” rice variety against Rhyzopertha dominica and Sitophilus oryzae. Low (RHAL) and high (RHAH) application rates of RHA, corresponding to 0.5 and 1 g kg-1, respectively, were evaluated against both weevils on wheat. Insecto®, a commercial DE, ...

  8. Complexity of rice Hsp100 gene family: lessons from rice genome ...

    Indian Academy of Sciences (India)

    Madhu Sudhan

    2007-03-29

    Mar 29, 2007 ... Nuclear genome of A. thaliana was the first one to be completely ... While the structural features of different. Arabidopsis .... DNA. Furthermore, all rice Hsp100 homologs were noted to possess AAA family conserved motif. AAA superfamily of ATPases are associated with a wide variety of cellular activities ...

  9. Antagonistic, overlapping and distinct responses to biotic stress in rice (Oryza sativa) and interactions with abiotic stress

    Science.gov (United States)

    2013-01-01

    Background Every year, substantial crop loss occurs globally, as a result of bacterial, fungal, parasite and viral infections in rice. Here, we present an in-depth investigation of the transcriptomic response to infection with the destructive bacterial pathogen Xanthomonas oryzae pv. oryzae(Xoo) in both resistant and susceptible varieties of Oryza sativa. A comparative analysis to fungal, parasite and viral infection in rice is also presented. Results Within 24 h of Xoo inoculation, significant reduction of cell wall components and induction of several signalling components, membrane bound receptor kinases and specific WRKY and NAC transcription factors was prominent, providing a framework for how the presence of this pathogen was signalled and response mounted. Extensive comparative analyses of various other pathogen responses, including in response to infection with another bacterium (Xoc), resistant and susceptible parasite infection, fungal, and viral infections, led to a proposed model for the rice biotic stress response. In this way, a conserved induction of calcium signalling functions, and specific WRKY and NAC transcription factors, was identified in response to all biotic stresses. Comparison of these responses to abiotic stress (cold, drought, salt, heat), enabled the identification of unique genes responsive only to bacterial infection, 240 genes responsive to both abiotic and biotic stress, and 135 genes responsive to biotic, but not abiotic stresses. Functional significance of a number of these genes, using genetic inactivation or over-expression, has revealed significant stress-associated phenotypes. While only a few antagonistic responses were observed between biotic and abiotic stresses, e.g. for a number of endochitinases and kinase encoding genes, some of these may be crucial in explaining greater pathogen infection and damage under abiotic stresses. Conclusions The analyses presented here provides a global view of the responses to multiple

  10. Rice that Filipinos Grow and Eat

    OpenAIRE

    de Leon, John C.

    2011-01-01

    This paper introduces rice to the reader and analyzes the changes it has gone through these past 100 years in the shaping hands of varietal improvement science. Here, the richness of the crop as a genetic material and resource is revealed. Landrace rice, pureline selection rice, crossbred rice, semidwarf rice, hybrid rice, new plant type rice, designer rice - from the traditional to modern to futuristic - rice becomes all of these while traversing time in the Philippines. There is rice for th...

  11. Application of Rice Straw Compost with Different Bioactivators on the Growth and Yield of Rice Plant

    Directory of Open Access Journals (Sweden)

    Yunita Barus

    2012-01-01

    Full Text Available Turnover of organic matters to the soil can increase the efficiency of chemical fertilizers, improve the plant growthand sustain the environment. Field experiment was carried out in the Buyut Udik Village, Gunung Sugih District,Central Lampung from May to August 2009. Rice straw was composted by three kinds of decomposer (bioactivatorA, B, and C. Rice straw compost (2 Mg ha-1 was applied to the paddy-field soil that was planted by rice (Oryzasativa of Ciherang Variety. The experiment was arranged in a randomized block design with three replicates. Theresults showed that application of rice straw compost reduced the numbers of empty grain per tiller compared tocontrol (without compost in which control had the highest percentage of empty grain (15.9%. The application ofrice straw compost that was decomposed by bioactivator A gave the highest numbers of grain per panicle and yieldper plot as followed 162.5 seed and 33 kg plot-1, respectively. Application of various rice straw composts that weredecomposed by three kinds of bioactivator increased the rice grain up to 13-26% compared to control.

  12. Genome-wide patterns of nucleotide polymorphism in domesticated rice.

    Directory of Open Access Journals (Sweden)

    Ana L Caicedo

    2007-09-01

    Full Text Available Domesticated Asian rice (Oryza sativa is one of the oldest domesticated crop species in the world, having fed more people than any other plant in human history. We report the patterns of DNA sequence variation in rice and its wild ancestor, O. rufipogon, across 111 randomly chosen gene fragments, and use these to infer the evolutionary dynamics that led to the origins of rice. There is a genome-wide excess of high-frequency derived single nucleotide polymorphisms (SNPs in O. sativa varieties, a pattern that has not been reported for other crop species. We developed several alternative models to explain contemporary patterns of polymorphisms in rice, including a (i selectively neutral population bottleneck model, (ii bottleneck plus migration model, (iii multiple selective sweeps model, and (iv bottleneck plus selective sweeps model. We find that a simple bottleneck model, which has been the dominant demographic model for domesticated species, cannot explain the derived nucleotide polymorphism site frequency spectrum in rice. Instead, a bottleneck model that incorporates selective sweeps, or a more complex demographic model that includes subdivision and gene flow, are more plausible explanations for patterns of variation in domesticated rice varieties. If selective sweeps are indeed the explanation for the observed nucleotide data of domesticated rice, it suggests that strong selection can leave its imprint on genome-wide polymorphism patterns, contrary to expectations that selection results only in a local signature of variation.

  13. Phylogenetic diversity and relationships among 40 rice accessions ...

    African Journals Online (AJOL)

    SERVER

    techniques. Ogunbayo S.A1,2*, Ojo D.K2, Guei R.G1Ώ, Oyelakin O.O3 and Sanni K.A1. 1Africa Rice Center (WARDA), 01 B.P. 2551, Bouaké 01, Côte d'Ivoire. 2Department of ... the genetic base of improved rice varieties, and the first step towards ... created within each replicate and unreplicated entries for which there are ...

  14. Gene, protein and network of male sterility in rice

    OpenAIRE

    Wang eKun; Peng eXiaojue; Ji eYanxiao; Pingfang eYang; Zhu eYingguo; Shaoqing eLi

    2013-01-01

    Rice is one of the most important model crop plants whose heterosis has been well exploited in commercial hybrid seed production via a variety of types of male sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes an...

  15. Gene, protein, and network of male sterility in rice

    OpenAIRE

    Wang, Kun; Peng, Xiaojue; Ji, Yanxiao; Yang, Pingfang; Zhu, Yingguo; Li, Shaoqing

    2013-01-01

    Rice is one of the most important model crop plants whose heterosis has been well-exploited in commercial hybrid seed production via a variety of types of male-sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and prot...

  16. Hypatropis inermis (Hemiptera, Pentatomidae: first record on rice crops

    Directory of Open Access Journals (Sweden)

    Diones Krinski

    2015-03-01

    Full Text Available This study reports for the first time the occurrence of Hypatropis inermis on upland rice crops (variety Cambará, in Novo Progresso, state of Pará, Brazil (7°07'45.71"S 55°23'21.13"W. The inventory of insect pests was conducted between November 2010 and March 2011 with entomological sweep nets and visual search on stems of rice plants. This record indicates that rice crops may represent important feeding and mating sites for this species.

  17. Rice improvement through radiation-induced mutation for cultivation in South Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Do Khac Thinh; Hung Phi Oanh; Nguyen Thi Cuc; Nguyen Ngoc Quynh [Institute of Agricultural Science of South Vietnam, Ho Chi Minh (Viet Nam)

    2001-03-01

    For past years, rice varieties cultivated in South Vietnam originated from domestic hybridisation or from IRRI. Rice mutation breeding has been initiated for recent years. To meet the requirement of rice production diversification in different agro-ecological areas and rice genetic resources, from 1993 Institute of Agricultural Science of South Vietnam has carried out rice improvement by induced mutation of radiation. The mutagen was gamma rays of {sup 60}Co. The goal is to create inherited variations, which cannot be obtained from other breeding methods, specially important characters of rice varieties (high tolerance to acid sulfate soil, lodging resistance combined with early maturity), which were difficult to gain by hybridisation. With {sup 60}Co gamma rays, doses of 10-20 krad, dose rate of 280 krad/h, dry and germinated seeds of introduced and local rice varieties (IR 64, IR 9729, IR 50404, IR 59606, Jasmine 85, Nang Huong, Tam Xoan) were irradiated. The irradiated seeds were immediately sown within 24 and 94 hrs for wet seeds and dry seeds after treatment, respectively. Population of 10,000-15,000 plants were established and evaluated by IRRI evaluation standard from M2-M7 generations. 365 lines, varieties were selected with better behaviours than original varieties as lodging resistance, earliness, potential yield, leaf characters, tolerant ability to adverse conditions etc. Some good varieties (VND95-19, VND95-20) have been approved as leading national varieties and released for large-scale production in South Vietnam. (author)

  18. Biochemical and Anatomical Changes and Yield Reduction in Rice (Oryza sativa L.) under Varied Salinity Regimes

    Science.gov (United States)

    Hakim, M. A.; Juraimi, Abdul Shukor; Hanafi, M. M.; Ismail, Mohd Razi; Selamat, Ahmad; Rafii, M. Y.; Latif, M. A.

    2014-01-01

    Five Malaysian rice (Oryza sativa L.) varieties, MR33, MR52, MR211, MR219, and MR232, were tested in pot culture under different salinity regimes for biochemical response, physiological activity, and grain yield. Three different levels of salt stresses, namely, 4, 8, and 12 dS m−1, were used in a randomized complete block design with four replications under glass house conditions. The results revealed that the chlorophyll content, proline, sugar content, soluble protein, free amino acid, and yield per plant of all the genotypes were influenced by different salinity levels. The chlorophyll content was observed to decrease with salinity level but the proline increased with salinity levels in all varieties. Reducing sugar and total sugar increased up to 8 dS m−1 and decreased up to 12 dS m−1. Nonreducing sugar decreased with increasing the salinity levels in all varieties. Soluble protein and free amino acid also decreased with increasing salinity levels. Cortical cells of MR211 and MR232 did not show cell collapse up to 8 dS m−1 salinity levels compared to susceptible checks (IR20 and BRRI dhan29). Therefore, considering all parameters, MR211 and MR232 showed better salinity tolerance among the tested varieties. Both cluster and principal component analyses depict the similar results. PMID:24579076

  19. Variety specificity of soft wheat varieties at organic production

    OpenAIRE

    Ilievski, Mite; Spasova, Dragica; Kukutanov, Risto; Atanasova, Biljana; Jovanov, Dalibor

    2013-01-01

    Surveys were conducted from 2004/05 to 2007/08 on ten (10) genotypes soft winter wheat. The main objective was to determine the variety specificity on wheat in organic production and to recommend varieties that will suit for organic production. Varieties podobrena orovchanka, lizinka, mila, bistra, orovchanka and olga are best and most stable genotypes for high yield of good quality in organic wheat production. Key words: wheat, organic, varieties, specification, grain

  20. Splicing and alternative splicing in rice and humans

    Directory of Open Access Journals (Sweden)

    Zhiguo E

    2013-09-01

    Full Text Available Rice is a monocot gramineous crop, and one of the mostimportant staple foods. Rice is considered a model species formost gramineous crops. Extensive research on rice hasprovided critical guidance for other crops, such as maize andwheat. In recent years, climate change and exacerbated soildegradation have resulted in a variety of abiotic stresses, suchas greenhouse effects, lower temperatures, drought, floods,soil salinization and heavy metal pollution. As such, there isan extremely high demand for additional research, in order toaddress these negative factors. Studies have shown that thealternative splicing of many genes in rice is affected by stressconditions, suggesting that manipulation of the alternativesplicing of specific genes may be an effective approach for riceto adapt to abiotic stress. With the advancement ofmicroarrays, and more recently, next generation sequencingtechnology, several studies have shown that more than half ofthe genes in the rice genome undergo alternative splicing. Thismini-review summarizes the latest progress in the research ofsplicing and alternative splicing in rice, compared to splicingin humans. Furthermore, we discuss how additional studiesmay change the landscape of investigation of rice functionalgenomics and genetically improved rice. [BMB Reports 2013;46(9: 439-447

  1. Current Insights into Research on Rice stripe virus

    Directory of Open Access Journals (Sweden)

    Won Kyong Cho

    2013-09-01

    Full Text Available Rice stripe virus (RSV is one of the most destructive viruses of rice, and greatly reduces rice production in China, Japan, and Korea, where mostly japonica cultivars of rice are grown. RSV is transmitted by the small brown plant-hopper (SBPH in a persistent and circulative-propagative manner. Several methods have been developed for detection of RSV, which is composed of four single-stranded RNAs that encode seven proteins. Genome sequence data and comparative phylogenetic analysis have been used to identify the origin and diversity of RSV isolates. Several rice varieties resistant to RSV have been selected and QTL analysis and fine mapping have been intensively performed to map RSV resistance loci or genes. RSV genes have been used to generate several genetically modified transgenic rice plants with RSV resistance. Recently, genome-wide transcriptome analyses and deep sequencing have been used to identify mRNAs and small RNAs involved in RSV infection; several rice host factors that interact with RSV proteins have also been identified. In this article, we review the current statues of RSV research and propose integrated approaches for the study of interactions among RSV, rice, and the SBPH.

  2. Acclimation and Tolerance Strategies of Rice under Drought Stress

    Directory of Open Access Journals (Sweden)

    Veena Pandey

    2015-07-01

    Full Text Available Rice (Oryza sativa L. is an important food crop and requires larger amount of water throughout its life cycle as compared to other crops. Hence, water related stress cause severe threat to rice production. Drought is a major challenge limiting rice production. It affects rice at morphological (reduced germination, plant height, plant biomass, number of tillers, various root and leaf traits, physiological (reduced photosynthesis, transpiration, stomatal conductance, water use efficiency, relative water content, chlorophyll content, photosystem II activity, membrane stability, carbon isotope discrimination and abscisic acid content, biochemical (accumulation of osmoprotectant like proline, sugars, polyamines and antioxidants and molecular (altered expression of genes which encode transcription factors and defence related proteins levels and thereby affects its yield. To facilitate the selection or development of drought tolerant rice varieties, a thorough understanding of the various mechanisms that govern the yield of rice under water stress condition is a prerequisite. Thus, this review is focused mainly on recent information about the effects of drought on rice, rice responses as well as adaptation mechanisms to drought stress.

  3. Evolutionary Insights Based on SNP Haplotypes of Red Pericarp, Grain Size and Starch Synthase Genes in Wild and Cultivated Rice

    Directory of Open Access Journals (Sweden)

    Nisha Singh

    2017-06-01

    Full Text Available The origin and domestication of rice has been a subject of considerable debate in the post-genomic era. Rice varieties have been categorized based on isozyme and DNA markers into two broad cultivar groups, Indica and Japonica. Among other well-known cultivar groups Aus varieties are closer to Indica and Aromatic varieties including Basmati are closer to Japonica, while deep-water rice varieties share kinship to both Indica and Japonica cultivar groups. Here, we analyzed haplotype networks and phylogenetic relationships in a diverse set of genotypes including Indian Oryza nivara/Oryza rufipogon wild rice accessions and representative varieties of four rice cultivar groups based on pericarp color (Rc, grain size (GS3 and eight different starch synthase genes (GBSSI, SSSI, SSIIa, SSIIb, SSIIIa, SSIIIb, SSIVa, and SSIVb. Aus cultivars appear to have the most ancient origin as they shared the maximum number of haplotypes with the wild rice populations, while Indica, Japonica and Aromatic cultivar groups showed varying phylogenetic origins of these genes. Starch synthase genes showed higher variability in cultivated rice than wild rice populations, suggesting diversified selection during and after domestication. O. nivara/O. rufipogon wild rice accessions belonging to different sub-populations shared common haplotypes for all the 10 genes analyzed. Our results support polyphyletic origin of cultivated rice with a complex pattern of migration of domestication alleles from wild to different rice cultivar groups. The findings provide novel insights into evolutionary and domestication history of rice and will help utilization of wild rice germplasm for genetic improvement of rice cultivars.

  4. Evolutionary Insights Based on SNP Haplotypes of Red Pericarp, Grain Size and Starch Synthase Genes in Wild and Cultivated Rice

    Science.gov (United States)

    Singh, Nisha; Singh, Balwant; Rai, Vandna; Sidhu, Sukhjeet; Singh, Ashok K.; Singh, Nagendra K.

    2017-01-01

    The origin and domestication of rice has been a subject of considerable debate in the post-genomic era. Rice varieties have been categorized based on isozyme and DNA markers into two broad cultivar groups, Indica and Japonica. Among other well-known cultivar groups Aus varieties are closer to Indica and Aromatic varieties including Basmati are closer to Japonica, while deep-water rice varieties share kinship to both Indica and Japonica cultivar groups. Here, we analyzed haplotype networks and phylogenetic relationships in a diverse set of genotypes including Indian Oryza nivara/Oryza rufipogon wild rice accessions and representative varieties of four rice cultivar groups based on pericarp color (Rc), grain size (GS3) and eight different starch synthase genes (GBSSI, SSSI, SSIIa, SSIIb, SSIIIa, SSIIIb, SSIVa, and SSIVb). Aus cultivars appear to have the most ancient origin as they shared the maximum number of haplotypes with the wild rice populations, while Indica, Japonica and Aromatic cultivar groups showed varying phylogenetic origins of these genes. Starch synthase genes showed higher variability in cultivated rice than wild rice populations, suggesting diversified selection during and after domestication. O. nivara/O. rufipogon wild rice accessions belonging to different sub-populations shared common haplotypes for all the 10 genes analyzed. Our results support polyphyletic origin of cultivated rice with a complex pattern of migration of domestication alleles from wild to different rice cultivar groups. The findings provide novel insights into evolutionary and domestication history of rice and will help utilization of wild rice germplasm for genetic improvement of rice cultivars. PMID:28649256

  5. Determinants for grading Malaysian rice

    Science.gov (United States)

    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.

  6. Recurrent parent genome recovery analysis in a marker-assisted backcrossing program of rice (Oryza sativa L.).

    Science.gov (United States)

    Miah, Gous; Rafii, Mohd Y; Ismail, Mohd R; Puteh, Adam B; Rahim, Harun A; Latif, Mohammad A

    2015-02-01

    Backcross breeding is the most commonly used method for incorporating a blast resistance gene into a rice cultivar. Linkage between the resistance gene and undesirable units can persist for many generations of backcrossing. Marker-assisted backcrossing (MABC) along with marker-assisted selection (MAS) contributes immensely to overcome the main limitation of the conventional breeding and accelerates recurrent parent genome (RPG) recovery. The MABC approach was employed to incorporate (a) blast resistance gene(s) from the donor parent Pongsu Seribu 1, the blast-resistant local variety in Malaysia, into the genetic background of MR219, a popular high-yielding rice variety that is blast susceptible, to develop a blast-resistant MR219 improved variety. In this perspective, the recurrent parent genome recovery was analyzed in early generations of backcrossing using simple sequence repeat (SSR) markers. Out of 375 SSR markers, 70 markers were found polymorphic between the parents, and these markers were used to evaluate the plants in subsequent generations. Background analysis revealed that the extent of RPG recovery ranged from 75.40% to 91.3% and from 80.40% to 96.70% in BC1F1 and BC2F1 generations, respectively. In this study, the recurrent parent genome content in the selected BC2F2 lines ranged from 92.7% to 97.7%. The average proportion of the recurrent parent in the selected improved line was 95.98%. MAS allowed identification of the plants that are more similar to the recurrent parent for the loci evaluated in backcross generations. The application of MAS with the MABC breeding program accelerated the recovery of the RP genome, reducing the number of generations and the time for incorporating resistance against rice blast. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  7. X-ray photoelectron spectroscopic analysis of rice kernels and flours: Measurement of surface chemical composition.

    Science.gov (United States)

    Nawaz, Malik A; Gaiani, Claire; Fukai, Shu; Bhandari, Bhesh

    2016-12-01

    The objectives of this study were to evaluate the ability of X-ray photoelectron spectroscopy (XPS) to differentiate rice macromolecules and to calculate the surface composition of rice kernels and flours. The uncooked kernels and flours surface composition of the two selected rice varieties, Thadokkham-11 (TDK11) and Doongara (DG) demonstrated an over-expression of lipids and proteins and an under-expression of starch compared to the bulk composition. The results of the study showed that XPS was able to differentiate rice polysaccharides (mainly starch), proteins and lipids in uncooked rice kernels and flours. Nevertheless, it was unable to distinguish components in cooked rice samples possibly due to complex interactions between gelatinized starch, denatured proteins and lipids. High resolution imaging methods (Scanning Electron Microscopy and Confocal Laser Scanning Microscopy) were employed to obtain complementary information about the properties and location of starch, proteins and lipids in rice kernels and flours. Copyright © 2016. Published by Elsevier Ltd.

  8. Characterization of Three Indica Rice Multiparent Advanced Generation Intercross (MAGIC) Populations for Quantitative Trait Loci Identification

    OpenAIRE

    Lijun Meng; Longbiao Guo; Kimberly Ponce; Xiangqian Zhao; Guoyou Ye

    2016-01-01

    Three new rice ( L.) multiparent advanced generation intercross (MAGIC) populations were developed using eight elite rice varieties from different breeding programs. These three populations were two recombinant inbred line (RIL) populations derived from two 4-way crosses, DC1 and DC2, and one RIL population derived from an 8-way cross. These populations were genotyped using an Illumina Infinium rice 6K SNP chip. The potential of the three MAGIC populations in identifying marker–trait associa...

  9. Optimization of Bread Preparation from Wheat Flour and Malted Rice Flour

    OpenAIRE

    Subajiny VELUPPILLAI; Ketheeswary NITHYANANTHARAJAH; Seevaratnam VASANTHARUBA; Sandrasegarampillai BALAKUMAR; Vasanthy ARASARATNAM

    2010-01-01

    The feasibility of partially replacing wheat flour with malted rice flour in bread making was evaluated in several formulations, aiming to find a formulation for the production of malted rice-wheat bread with better nutritional quality and consumer acceptance. The whole grains of a local rice variety (Oryza sativa L. subsp. indica var. Mottaikaruppan) were steeped in distilled water (12 h, 30°C) and germinated for 3 days to obtain high content of soluble materials and amylase activity in brea...

  10. In silico study of interaction between rice proteins enhanced disease ...

    Indian Academy of Sciences (India)

    2012-06-25

    Jun 25, 2012 ... In silico study of interaction between rice proteins enhanced disease susceptibility 1 and phytoalexin deficient 4, the regulators of salicylic acid signalling pathway. INDRA SINGH. 1 and KAVITA SHAH. 2,*. 1Department of Bioinformatics, MMV, 2Institute of Environment & Sustainable Development,. Banaras ...

  11. Evaluation of Rice Resistance to Southern Rice Black-Streaked Dwarf Virus and Rice Ragged Stunt Virus through Combined Field Tests, Quantitative Real-Time PCR, and Proteome Analysis

    Directory of Open Access Journals (Sweden)

    Zhenchao Wang

    2017-02-01

    Full Text Available Diseases caused by southern rice black-streaked dwarf virus (SRBSDV and rice ragged stunt virus (RRSV considerably decrease grain yield. Therefore, determining rice cultivars with high resistance to SRBSDV and RRSV is necessary. In this study, rice cultivars with high resistance to SRBSDV and RRSV were evaluated through field trials in Shidian and Mangshi county, Yunnan province, China. SYBR Green I-based quantitative real-time polymerase chain reaction (qRT-PCR analysis was used to quantitatively detect virus gene expression levels in different rice varieties. The following parameters were applied to evaluate rice resistance: acre yield (A.Y., incidence of infected plants (I.I.P., virus load (V.L., disease index (D.I., and insect quantity (I.Q. per 100 clusters. Zhongzheyou1 (Z1 and Liangyou2186 (L2186 were considered the most suitable varieties with integrated higher A.Y., lower I.I.P., V.L., D.I. and I.Q. features. In order to investigate the mechanism of rice resistance, comparative label-free shotgun liquid chromatography tandem-mass spectrometry (LC-MS/MS proteomic approaches were applied to comprehensively describe the proteomics of rice varieties’ SRBSDV tolerance. Systemic acquired resistance (SAR-related proteins in Z1 and L2186 may result in the superior resistance of these varieties compared with Fengyouxiangzhan (FYXZ.

  12. Molecular mapping of qBK1WD, a major QTL for bakanae disease resistance in rice.

    Science.gov (United States)

    Lee, Sais-Beul; Hur, Yeon-Jae; Cho, Jun-Hyeon; Lee, Jong-Hee; Kim, Tae-Heon; Cho, Soo-Min; Song, You-Chun; Seo, Young-Su; Lee, Jungkwan; Kim, Tae-Sung; Park, Yong-Jin; Oh, Myung-Kyu; Park, Dong-Soo

    2018-01-10

    Bakanae or foot rot disease is a prominent disease of rice caused by Gibberella fujikuroi. This disease may infect rice plants from the pre-emergence stage to the mature stage. In recent years, raising rice seedlings in seed boxes for mechanical transplanting has increased the incidence of many seedling diseases; only a few rice varieties have been reported to exhibit resistance to bakanae disease. In this study, we attempted to identify quantitative trait loci (QTLs) conferring bakanae disease resistance from the highly resistant japonica variety Wonseadaesoo. A primary QTL study using the genotypes/phenotypes of the recombinant inbred lines (RILs) indicated that the locus qBK1 WD conferring resistance to bakanae disease from Wonseadaesoo was located in a 1.59 Mb interval delimited on the physical map between chr01_13542347 (13.54 Mb) and chr01_15132528 (15.13 Mb). The log of odds (LOD) score of qBK1 WD was 8.29, accounting for 20.2% of the total phenotypic variation. We further identified a gene pyramiding effect of two QTLs, qBK WD and previously developed qBK1. The mean proportion of healthy plant for 31 F 4 RILs that had no resistance genes was 35.3%, which was similar to that of the susceptible check variety Ilpum. The proportion of healthy plants for the lines with only qBK WD or qBK1 was 66.1% and 55.5%, respectively, which was significantly higher than that of the lines without resistance genes and that of Ilpum. The mean proportion of the healthy plant for 15 F 4 RILs harboring both qBK WD and qBK1 was 80.2%, which was significantly higher than that of the lines with only qBK WD or qBK1. Introducing qBK WD or pyramiding the QTLs qBK WD and qBK1 could provide effective tools for breeding rice with bakanae disease resistance. To our knowledge, this is the first report on a gene pyramiding effect that provides higher resistance against bakanae disease.

  13. Rice (Oryza) hemoglobins

    Science.gov (United States)

    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. economics of rice production

    African Journals Online (AJOL)

    ABSTRACT. Local rice production is being promoted in Ghana to reduce the' dependence on im- ports, ensure stable low-prices food for the population and also create employment. This paper examines three rice production systems; Upland, Valley Bottom and Irri- gated, in the Upper East Region of Ghana with a view to ...

  15. Comparison of saccharification and fermentation of steam exploded rice straw and rice husk.

    Science.gov (United States)

    Wood, Ian P; Cao, Huong-Giang; Tran, Long; Cook, Nicola; Ryden, Peter; Wilson, David R; Moates, Graham K; Collins, Samuel R A; Elliston, Adam; Waldron, Keith W

    2016-01-01

    Rice cultivation produces two waste streams, straw and husk, which could be exploited more effectively. Chemical pretreatment studies using rice residues have largely focussed on straw exploitation alone, and often at low substrate concentrations. Moreover, it is currently not known how rice husk, the more recalcitrant residue, responds to steam explosion without the addition of chemicals. The aim of this study has been to systematically compare the effects of steam explosion severity on the enzymatic saccharification and simultaneous saccharification and fermentation of rice straw and husk produced from a variety widely grown in Vietnam (Oryza sativa, cv. KhangDan18). Rice straw and husk were steam exploded (180-230 °C for 10 min) into hot water and washed to remove fermentation inhibitors. In both cases, pretreatment at 210 °C and above removed most of the noncellulosic sugars. Prolonged saccharification at high cellulase doses showed that rice straw could be saccharified most effectively after steam explosion at 210 °C for 10 min. In contrast, rice husk required more severe pretreatment conditions (220 °C for 10 min), and achieved a much lower yield (75 %), even at optimal conditions. Rice husk also required a higher cellulase dose for optimal saccharification (10 instead of 6 FPU/g DM). Hemicellulase addition failed to improve saccharification. Small pilot scale saccharification at 20 % (w/v) substrate loading in a 10 L high torque bioreactor resulted in similarly high glucose yields for straw (reaching 9 % w/v), but much less for husk. Simultaneous saccharification and fermentation under optimal pretreatment and saccharification conditions showed similar trends, but the ethanol yield from the rice husk was less than 40 % of the theoretical yield. Despite having similar carbohydrate compositions, pretreated rice husk is much less amenable to saccharification than pretreated rice straw. This is likely to attenuate its use as a biorefinery

  16. Nutrient Removal by Rice Cultivated in Newly Opened Wetland Rice in Bulungan District, East Kalimantan

    Directory of Open Access Journals (Sweden)

    Sukristiyonubowo

    2012-05-01

    Full Text Available Highly weathered Indonesian soils and potential acid sulphate soils are mainly granted for developing newlyopened wetland rice field to meet rice growing demand in Indonesia. Nutrient removal by rice harvest product ofCiliwung variety planted in newly opened wetland rice was studied in Bulungan District, in 2009. The aims were toexamine the nutrient taken out by rice harvest product and to properly manage its fertility status to sustain ricefarming. Six treatments were studied including T0: farmers practices, T1: farmer practices + compost + dolomite, T2:NPK recommended rate, N and K were split two times, T3: NPK recommended rate, N and K were split three times,T4: NPK recommended rate, N and K were split three times + compost + dolomite and T5: NPK recommended rate,N and K were split two times + compost + dolomite. The results indicated that the highest concentrations of N, P,and K in rice grain and rice straw were observed at NPK with recommendation rate in which N and K were split threetimes + straw compost + dolomite (T4. The T4 (NPK with recommendation rate in which N and K were split threetimes + straw compost + dolomite also showed the highest nutrient removal by harvest product. Depending on thetreatments, total nutrients removal through rice grains and rice straw varied from 61.81 to 101.71 kg N, 4.31 to13.69 kg P and from 95.77 to 171.16 kg K ha-1 season-1, meaning that at least about 137 to 225 kg urea, 50 to 160kg SP-36 and 190 to 339 kg KCl ha-1 season-1 should be given to replace nutrient removed by harvest product andto avoid any nutrients depletion. When all rice straws were returned to the field as compost, about 55 to 133 kg urea,25 to 110 kg SP-36 and 10 to 19 kg KCl ha-1 season-1 should be added to substitute nutrient removed by rice grain.

  17. METHANE EMISSION FROM DIRECT SEEDED RICE UNDER THE INFLUENCES OF RICE STRAW AND NITRIFICATION INHIBITOR

    Directory of Open Access Journals (Sweden)

    A. Wihardjaka

    2013-04-01

    Full Text Available Incorporation of rice straw into soil is a common practice to improve soil productivity and increase inorganic fertilizer availability. However, this practice could contribute to methane (CH4 emission; one of the greenhouse gases that causes global warming. Nitrification inhibitors such as neem cake and carbofuran may reduce methane emission following application of rice straw. The study aimed to evaluate the application of rice straw and nitrification inhibitor to methane emission in rainfed lowland rice system. A factorial randomized block design was used with three replications. The first factor was rice straw incorporation (5 t ha-1 fresh straw, 5 t ha-1 composted straw, and the second factor was nitrification inhibitor application (20 kg ha-1 neem cake, 20 kg ha-1 carbofuran. The experiment was conducted at rainfed lowland in Pati, Central Java, during 2009/2010 wet season. Ciherang variety was planted as direct seeded rice with spacing of 20 cm x 20 cm in each plot of 4 m x 5 m. The rice straw was treated together with soil tillage, whereas nitrification inhibitor was applied together with urea application. Parameters observed were methane flux, plant height, plant biomass, grain yield, organic C content, and bacterial population in soil. The methane flux and soil organic C were measured at 25, 45, 60, 75, and 95 days after emergence. The results showed that composted rice straw incorporation significantly emitted methane lower (73.2 ± 6.6 kg CH4 ha-1 season-1 compared to the fresh rice straw (93.5 ± 4.0 CH4 ha-1 season-1. Application of nitrification inhibitors neem cake and carbofuran reduced methane emission as much as 20.7 and 15.4 kg CH4 ha-1 season-1, respectively. Under direct seeded rice system, methane flux level correlated with plant biomass as shown by linear regression of Y = 0.0015 X + 0.0575 (R2 = 0.2305, n = 27. This means that higher plant biomass produced more methane flux. The study indicates that application of

  18. Developed Maize Varieties in Nigeria.

    African Journals Online (AJOL)

    white dent, improved yellow dent and local floury respectively. The major carbohydrate in all the varieties was starch with local floury having a slightly higher level of sugar. Improved yellow dent was significantly. (P<0.05) higher in Ca and Fe than other varieties. However, Wy-1 an improved yellow dent variety was.

  19. Abelian varieties over finite fields

    NARCIS (Netherlands)

    Oort, F.

    2006-01-01

    Utrecht, Spring School on abelian varieties: May 2006 We could try to classify isomorphism classes of abelian varieties. The theory of moduli spaces of polarized abelian varieties answers this question completely. This is a geometric theory. However in this general, abstract theory it is often

  20. Evaluation of tomato varieties for resistance to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Clayberg, C.D.

    1972-01-01

    Tomatoes are among the crops most sensitive to ozone. Many researchers tested various varieties for resistance. The tests indicated a variation among tomato varieties for resistance to ozone and that some commercial varieties were as resistant as any lines tested. In the USA and Canada a total of 295 different varieties and hybrids were received and tested for response to ozone during the summer of 1971. Plants were exposed to O/sub 3/ when the first true leaves were 2 1/2 to 4 inches long. Tomato leaves showed typical injury symptoms following exposure to O/sub 3/. Mild symptoms were a chlorotic yellowing or whitening of tissue between the leaf veins, or small brownish necrotic flecks marginally or all over the leaf. Severe damage resulted in large water-soaked areas over the entire leaf surface right after exposure to ozone. Of the various varieties, the most resistant were Pierette and Heinz 1439 in successive tests. Susceptible ones were Roma VF and Fruhernte. Charkowskij and New Yorker were of an intermediate level of resistance. All the ozone-resistant varieties of KY 1, VFN 8, PI 304234, PI 309915, and Manzana (PI 203229) were about equally susceptible under the conditions of testing used. The range between the most resistant and the most susceptible tomato varieties was not as great as in crops like tobacco. 8 references, 2 tables.

  1. Impact of Nitrogen, Phosphorus and Potassium on Brown Planthopper and Tolerance of Its Host Rice Plants

    Directory of Open Access Journals (Sweden)

    Md Mamunur Rashid

    2016-05-01

    Full Text Available The brown planthopper (BPH, Nilaparvata lugens (Stål, appeared as a devastating pest of rice in Asia. Experiments were conducted to study the effects of three nutrients, nitrogen (N, phosphorus (P and potassium (K, on BPH and its host rice plants. Biochemical constituents of BPH and rice plants with varying nutrient levels at different growth stages, and changes in relative water content (RWC of rice plants were determined in the laboratory. Feeding of BPH and the tolerance of rice plants to BPH with different nutrient levels were determined in the nethouse. Concentrations of N and P were found much higher in the BPH body than in its host rice plants, and this elemental mismatch is an inherent constraint on meeting nutritional requirements of BPH. Nitrogen was found as a more limiting element for BPH than other nutrients in rice plants. Application of N fertilizers to the rice plants increased the N concentrations both in rice plants and BPH while application of P and K fertilizers increased their concentrations in plant tissues only but not in BPH. Nitrogen application also increased the level of soluble proteins and decreased silicon content in rice plants, which resulted in increased feeding of BPH with sharp reduction of RWC in rice plants ultimately caused susceptible to the pest. P fertilization increased the concentration of P in rice plant tissues but not changed N, K, Si, free sugar and soluble protein contents, which indicated little importance of P to the feeding of BPH and tolerance of plant against BPH. K fertilization increased K content but reduced N, Si, free sugar and soluble protein contents in the plant tissues which resulted in the minimum reduction of RWC in rice plants after BPH feeding, thereby contributed to higher tolerance of rice plants to brown planthopper.

  2. Characterization of the in vitro response to NaCI on callus in multiplication and regeneration phase of some rice genotypes

    Directory of Open Access Journals (Sweden)

    Pedro Orellana Pérez

    2003-01-01

    Full Text Available This paper present the in vitro response in two different development stages of four rice somaclons for the salt tolerance using five NaCl concentrations. The evaluated somaclons were: ‘IAC 25’, ‘IAC 26’, ‘R 13 - K1 - 1- 2’ and ‘R 20 - K1 -1 – 2’. The varieties ‘Pokkali’ and ‘Mi 48’, were used as resistant and susceptible controls, respectively. It was find a differential reaction for tolerants and susceptibles genotypes for the salt tolerance in dependence of the NaCl concentration in the callus growing and regeneration stages. The regeneration stage showed higher sensibility to NaCl concentration. According with these results, the somaclon ‘IAC 25’ like the ‘Pokkali’ variety, expressed salt tolerance until 1.5% of NaCl in both development stages. The others somaclons presented low salt tolerance levels compared with the resistant variety. In the multiplication stage of the callus two continuous subcultures on the culture media with NaCl are necessary in order to express a clear differential reaction between tolerant and susceptible genotypes to this sal. Key words: callus, levels, regeneration, salinity, somaclons

  3. Evaluation of the Effects of Climate Change on Rice Production in ...

    African Journals Online (AJOL)

    Therefore, the study recommends that research should be done to find the means of reducing the effect of climate change which will in turn improve the agricultural sector of the economy and rice production specifically. Also, breeders should help to develop rice varieties that can survive and produce well in adverse climatic ...

  4. Potential of Azolla as a Nitrogenous Biofertiliser for Irrigated Rice at ...

    African Journals Online (AJOL)

    Potential of Azolla as a Nitrogenous Biofertiliser for Irrigated Rice at the Lower Moshi Irrigation Project, Tanzania. ... (indigenous) and IR54 (improved) rice varieties in a split-plot design with 3 replications, in 18 m2 plots each of which received a basal phosphate dose of 20 Kg P ha-1 as Tripe super phospate (TSP).

  5. Effect of soaking and phytase treatment on phytic acid, calcium, iron and zinc in rice fractions

    NARCIS (Netherlands)

    Liang, J.; Han, B.Z.; Nout, M.J.R.; Hamer, R.J.

    2009-01-01

    With the aim to maximise phytic acid removal and minimise losses of dry matter and minerals (Ca, Fe, Zn) in rice, three products (whole kernels and flour milled from white and brown rice; and bran, all from the same batch of variety Kenjian 90-31) were soaked in demineralized water at 10 °C (SDW),

  6. fungal diseases of rice in nursery farms in bayelsa state of nigeria

    African Journals Online (AJOL)

    A survey of fungi association with seed, seedling and straw samples of three rice varieties (Faro 12, Faro 15, and Maliong) obtained from 18 nursery farms in Okuokpoti-Ogbia, a major rice producing community in Ogbia Local Government area of Bayelsa State, Nigeria was investigated. Soil samples from the farms were ...

  7. Geographic and Research Center Origins of Rice Resistance to Asian Planthoppers and Leafhoppers: Implications for Rice Breeding and Gene Deployment

    Directory of Open Access Journals (Sweden)

    Finbarr G. Horgan

    2017-09-01

    Full Text Available This study examines aspects of virulence to resistant rice varieties among planthoppers and leafhoppers. Using a series of resistant varieties, brown planthopper, Nilaparvata lugens, virulence was assessed in seedlings and early-tillering plants at seven research centers in South and East Asia. Virulence of the whitebacked planthopper, Sogatella furcifera, in Taiwan and the Philippines was also assessed. Phylogenetic analysis of the varieties using single-nucleotide polymorphisms (SNPs indicated a clade of highly resistant varieties from South Asia with two further South Asian clades of moderate resistance. Greenhouse bioassays indicated that planthoppers can develop virulence against multiple resistance genes including genes introgressed from wild rice species. Nilaparvata lugens populations from Punjab (India and the Mekong Delta (Vietnam were highly virulent to a range of key resistance donors irrespective of variety origin. Sogatella furcifera populations were less virulent to donors than N. lugens; however, several genes for resistance to S. furcifera are now ineffective in East Asia. A clade of International Rice Research Institute (IRRI-bred varieties and breeding lines, without identified leafhopper-resistance genes, were highly resistant to the green leafhopper, Nephotettix virescens. Routine phenotyping during breeding programs likely maintains high levels of quantitative resistance to leafhoppers. We discuss these results in the light of breeding and deploying resistant rice in Asia.

  8. Looking Inward to the Use of Unmanned Aerial Vehicle (UAV) for Rice Production Assessment in Indonesia

    Science.gov (United States)

    Komaladara, A. A. S. P.; Ambarawati, I. G. A. A.; Wijaya, I. M. A. S.; Hongo, C.; Mirah Adi, A. A. A.

    2015-12-01

    Rice is the main source of carbohydrate for most Indonesians. Rice production has been very dynamic due to improved infrastructure, research and development, and better farm management. However, rice production is susceptible to loss caused by drought, pest and disease attack and climate change. With the growing concern on sustainable and self-reliance food production in the country, there is an urgency to encourage research and efforts to increase rice productivity. Attempts to provide spatial distribution of rice fields on high resolution optical remote sensing data have been employed to some extent, however this technology could be costly. The use of UAV has been introduced to estimate damage ratio in rice crop recently in Indonesia. This technology is one of the ways to estimate rice production quicker, cost-saving and before harvesting time. This study aims to analyze spatio temporal and damage ratio of rice crop using UAV in Indonesia. The study empirically presents the use of UAV (Phantom 2 Vision +) on rice fields to the soil condition and development of management zone map in Bali as an example. The study concludes that the use of UAV allows researchers to pin point characteristics of crop and land in a specific area of a farm. This will then allow researchers to assist farmers in implementing specific and appropriate solutions to production issues. Key words: UAV, rice production, damage ratio

  9. Degradation kinetics of aflatoxin B1 and B2 in filter paper and rough rice by using pulsed light irradiation

    Science.gov (United States)

    Rough rice is susceptible to contamination by aflatoxins, which are highly toxic, mutagenic and carcinogenic compounds. To develop aflatoxin degradation technology for rice with the use of pulsed light (PL) treatment, the objective of this study was to investigate the degradation characters of aflat...

  10. RESPONSE OF OXIDATIVE STRESS DEFENSE SYSTEMS IN RICE (ORYZA SATIVA) LEAVES WITH SUPPLEMENTAL UV-B RADIATION

    Science.gov (United States)

    The impact of elevated ultraviolet-B radiation (UV-B, 280-320 nm) on membrane systems and lipid peroxidation, and possible involvement of active oxygen radicals was investigated in leaves of two UV-B susceptible rice cultivars (Oryza sativa L. cvs IR74 and Dular). Rice seedlings ...

  11. Development of instant noodles from high-iron rice and iron-fortified rice flour

    Directory of Open Access Journals (Sweden)

    Suparat Reungmaneepaitoon

    2008-08-01

    Full Text Available Instant high-iron noodles, prepared from wheat flour and high iron brown rice flour, were developed. Three varieties of rice flour, Suphan Buri 90 (SB, Homnin 313 (HW and Homnin 1000 (HP, containing amylose content of 30.40, 19.10 and 15.74% (w/w and iron content of 1.24, 2.04 and 2.22 (mg/100 g respectively, were used to replace wheat flour for instant fried noodle production. To determine the physicochemical properties and acceptability of instant fried noodles,different percentages (30, 40, 50% (w/w of each rice flour sample were used. The instant fried noodles were fortified with ferrous sulphate at levels of 0, 32, 64% iron of RDI per serving. Increasing amount of iron content in the mixtures decreased the L* value, b* value and increased a* value for the color of the instant fried noodle with brown rice flour. The texture characteristic of the noodles with 30, 40, 50% replacement with each variety of brown rice flour were significantly different from those of wheat noodle. Tensile force of the noodles decreased from 11.57±1.30 g to 6.38±1.45 g (SB, 8.36±0.96 g to 5.71±0.57 g (HP and 10.09±1.20 g to 5.46±1.31 g (HW as the rice flour content increased from 30 to 50%. The sensoryacceptability of the noodles made from each variety of 30% brown rice flour fortified with 32% iron of RDI had higher preference scores for elasticity, firmness, color and overall acceptability, than those with 64% iron of RDI. Instant fried noodles with HW and HP brown rice flour were subjected to consumer test using 100 rural primary school children. The frequency percent of the acceptability scores of the noodle with HP and HW were 88 and 84% respectively. Shelf life studyrevealed that the developed products were still acceptable up to 4 months. These products were claimed to be high iron noodle.

  12. Lucerne varieties for continuous grazing

    DEFF Research Database (Denmark)

    Søegaard, Karen

    2012-01-01

    strength, the lowest plant density in spring, and the density was most reduced during grazing. The results could not confirm significant differences between the new and the older varieties. The results for Luzelle were generally between Verbena and Camporegio. The varieties did not differ in herbage...... severe grazing with heifers in two cutting/grazing managements. Two new varieties, Verbena and Camporegio, and an older variety Luzelle were established in 2009 in pure stands and in two different mixtures with perennial ryegrass (Lolium perenne). Camporegio had the lowest yield, the lowest competitive...

  13. Profiling the expression domains of a rice-specific microRNA under stress

    Directory of Open Access Journals (Sweden)

    Neha eSharma

    2015-05-01

    Full Text Available Plant microRNAs (miRs have emerged as important regulators of gene expression under normal as well as stressful environments. Rice is an important cereal crop whose productivity is compromised due to various abiotic stress factors such as salt, heat and drought. In the present study, we have investigated the role of rice-specific Osa-miR820, in indica rice cultivars showing contrasting response to salt stress. The dissection of expression patterns indicated that the miR is present in all the tissues but is enriched in the anther tissues. In salinity, the miR levels are up-regulated in the leaf tissues but down-regulated in the root tissues. To map the deregulation under salt stress comprehensive time kinetics of expression was performed in the leaf and root tissues. The reproductive stages were also analyzed under salt stress. It emerged that a common regulatory scheme for Osa-miR820 expression is present in the salt-susceptible Pusa Basmati 1 (PB1 and salt-tolerant Pokkali (PK varieties, although there is a variation in the levels of the miR and its target transcript, OsDRM2. The regulation of Osa-miR820 and its target were also studied under other abiotic stresses. This study thus captures the window for the miR-target correlation and the putative role of this regulation is discussed.This will help in gaining useful insights on the role of species specific miRs in plant development and abiotic stress response.

  14. Hypnotic susceptibility and dream characteristics.

    Science.gov (United States)

    Zamore, N; Barrett, D

    1989-11-01

    This study examined the relationship of hypnotic susceptibility to a variety of dream characteristics and types of dream content. A Dream Questionnaire was constructed synthesizing Gibson's dream inventory and Hilgard's theoretical conceptions of hypnosis. Employing the Harvard Group Scale of Hypnotic Susceptibility and the Field Inventory for evaluating hypnotic response, several dream dimensions correlated significantly with hypnotizability. For subjects as a whole, the strongest correlates were the frequency of dreams which they believed to be precognitive and out-of-body dreams. Ability to dream on a chosen topic also correlated significantly with hypnotic susceptibility for both genders. For females only, there was a negative correlation of hypnotic susceptibility to flying dreams. Absorption correlated positively with dream recall, ability to dream on a chosen topic, reports of conflict resolution in dreams, creative ideas occurring in dreams, amount of color in dreams, pleasantness of dreams, bizarreness of dreams, flying dreams and precognitive dreams.

  15. Genetic Loci Governing Grain Yield and Root Development under Variable Rice Cultivation Conditions.

    Science.gov (United States)

    Catolos, Margaret; Sandhu, Nitika; Dixit, Shalabh; Shamsudin, Noraziya A A; Naredo, Ma E B; McNally, Kenneth L; Henry, Amelia; Diaz, Ma G; Kumar, Arvind

    2017-01-01

    Drought is the major abiotic stress to rice grain yield under unpredictable changing climatic scenarios. The widely grown, high yielding but drought susceptible rice varieties need to be improved by unraveling the genomic regions controlling traits enhancing drought tolerance. The present study was conducted with the aim to identify quantitative trait loci (QTLs) for grain yield and root development traits under irrigated non-stress and reproductive-stage drought stress in both lowland and upland situations. A mapping population consisting of 480 lines derived from a cross between Dular (drought-tolerant) and IR64-21 (drought susceptible) was used. QTL analysis revealed three major consistent-effect QTLs for grain yield (qDTY1.1, qDTY1.3 , and qDTY8.1 ) under non-stress and reproductive-stage drought stress conditions, and 2 QTLs for root traits (qRT9.1 for root-growth angle and qRT5.1 for multiple root traits, i.e., seedling-stage root length, root dry weight and crown root number). The genetic locus qDTY1.1 was identified as hotspot for grain yield and yield-related agronomic and root traits. The study identified significant positive correlations among numbers of crown roots and mesocotyl length at the seedling stage and root length and root dry weight at depth at later stages with grain yield and yield-related traits. Under reproductive stage drought stress, the grain yield advantage of the lines with QTLs ranged from 24.1 to 108.9% under upland and 3.0-22.7% under lowland conditions over the lines without QTLs. The lines with QTL combinations qDTY1.3 +qDTY8.1 showed the highest mean grain yield advantage followed by lines having qDTY1.1 +qDTY8.1 and qDTY1.1 +qDTY8.1 +qDTY1.3 , across upland/lowland reproductive-stage drought stress. The identified QTLs for root traits, mesocotyl length, grain yield and yield-related traits can be immediately deployed in marker-assisted breeding to develop drought tolerant high yielding rice varieties.

  16. Hydrothermal processing of rice husks: effects of severity on product distribution

    NARCIS (Netherlands)

    Vegas, R.; Kabel, M.A.; Schols, H.A.; Alonso, J.L.; Parajo, J.C.

    2008-01-01

    BACKGROUND: Treatment in aqueous media (hydrothermal or autohydrolysis reactions) is an environmentally friendly technology for fractionating lignocellulosic materials. Rice husks were subjected to hydrothermal processing under a variety of operational conditions to cause the selective breakdown of

  17. Harnessing the hidden genetic diversity for improving multiple abiotic stress tolerance in rice (Oryza sativa L.)

    National Research Council Canada - National Science Library

    Jauhar Ali; Jian-Long Xu; Yong-Ming Gao; Xiu-Fang Ma; Li-Jun Meng; Ying Wang; Yun-Long Pang; Yong-Sheng Guan; Mei-Rong Xu; Jastin E Revilleza; Neil J Franje; Shao-Chuan Zhou; Zhi-Kang Li

    2017-01-01

      To develop superior rice varieties with improved yield in most rainfed areas of Asia/Africa, we started an introgression-breeding program for simultaneously improving yield and tolerances of multiple abiotic stresses...

  18. Field tolerance of selected varieties to and fungicide efficacy against ...

    African Journals Online (AJOL)

    The materials were planted in fields having a history of AB disease and rated for tolerance based on a General Disease Index (GDI), with the lowest scores representing tolerance, and the higher scores representing susceptibility. Variety 199062-1 had the lowest GDI value, and was the most tolerant to AB; while W119 had ...

  19. Cambodia Rice Sector Review

    OpenAIRE

    World Bank Group

    2015-01-01

    Cambodia’s rice harvests have been rising significantly since 2005, powered by improved and expanded irrigation and attractive farm gate prices. In 2010, the Cambodian government announced an export target of 1.0 million tons of milled rice by 2015. This analysis, which updates reports prepared in 2009 and 2011, seeks to identify short-term policy measures that can assist Cambodian exporte...

  20. [Impacts of climate warming on growth period and yield of rice in Northeast China during recent two decades].

    Science.gov (United States)

    Hou, Wen-jia; Geng, Ting; Chen, Qun; Chen, Chang-qing

    2015-01-01

    By using rice growth period, yield and climate observation data during the recent two decades, the impact of climate warming on rice in Northeast China was investigated by mathematical statistics methods. The results indicated that in the three provinces of Northeast China, the average, maximum and minimum temperatures in rice growing season were on the. rise, and the rainfall presented a downward trend during 1989-2009. Compared to 1990s, the rice whole growth periods of Heilongjiang, Jilin and Liaoning provinces in 2000s were prolonged 14 d, 4.5 d and 5.1 d, respectively. The increase of temperature in May, June and September could extend the rice growth period, while that in July would shorten the growth duration. The rice growth duration of registered varieties and experiment sites had a similar increasing trend in Northeast China except for the Heilongjiang Province, and the extension of registered varieties growth period was the main factor causing the prolonged growth period of rice at experiment sites. The change in daily average, minimum and maximum temperatures all could affect the rice yield in Northeast China. The increasing temperature significantly increased the rice yield in Heilongjiang Province, especially in the west region of Sanjiang Plain. Except for the south of Liaoning Province, rice yields in other regions of Northeast China were promoted by increasing temperature. Proper measures for breeding, cultivation and farming, could be adopted to fully improve the adaptation of rice to climate warming in Northeast China.

  1. Variability of Pyricularia oryzae Cav. in irrigated rice genotypes

    Directory of Open Access Journals (Sweden)

    Cley Donizeti Martins Nunes

    2014-09-01

    Full Text Available Rice blast, caused by the fungus Pyricularia oryzae Cav., is one of the most important diseases of rice. The understanding of its different strains allows a more efficient breeding towards resistant cultivars. This work aimed to determine the variability of the fungus and the prevalence of strains in irrigated rice genotypes, to evaluate the reaction of near isogenic lines of CO 39 to the collected P. oryzae isolates and to identify rice genotypes having complementary resistance genes to these isolates. The study was performed with 36 P. oryzae isolates collected in 18 irrigated rice cultivars from four counties in Rio Grande do Sul State, Brazil. A total of 21 strains were identified, with a prevalence for the IA group strains, in all collection sites, especially the IA-1 strain. A resistance reaction was observed for the cultivars BRS Firmeza, Bluebelle, Te-tep and BRS 7 (Taim, while a susceptible reaction was observed for Fanny, Dawn, BRS Pelota and BRS Atalanta. The series of near isogenic lines obtained from the CO 39 cultivar showed resistance to the isolates in the following order: C101 A51 (resistant to all isolates; C101 PKT (12; C104PKT (11; C105HP4L23 (8; and C101-LAC (3. From the studied isolates, it was concluded that there is variability of P. oryzae, prevalence of the IA strain, a higher tolerance for the cultivar BRS Firmeza and that the Pi-2 gene confers resistance to rice blast in all isolates analyzed.

  2. Nitrogen fertilizer application affects lodging resistance by altering secondary cell wall synthesis in japonica rice (Oryza sativa).

    Science.gov (United States)

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

    2017-09-01

    Stem mechanical strength is an important agricultural quantitative trait that is closely related to lodging resistance in rice, which is known to be reduced by fertilizer with higher levels of nitrogen. To understand the mechanism that regulates stem mechanical strength in response to nitrogen, we analysed stem morphology, anatomy, mechanical properties, cell wall components, and expression of cell wall-related genes, in two varieties of japonica rice, namely, Wuyunjing23 (lodging-resistant variety) and W3668 (lodging-susceptible variety). The results showed that higher nitrogen fertilizer increased the lodging index in both varieties due to a reduction in breaking strength and bending stress, and these changes were larger in W3668. Cellulose content decreased slightly under higher nitrogen fertilizer, whereas lignin content reduced remarkably. Histochemical staining revealed that high nitrogen application decreased lignin deposition in the secondary cell wall of the sclerenchyma cells and vascular bundle cells compared with the low nitrogen treatments, while it did not alter the pattern of cellulose deposition in these cells in both Wuyunjing23 and W3668. In addition, the expression of the genes involved in lignin biosynthesis, OsPAL, OsCoMT, Os4CL3, OsCCR, OsCAD2, OsCAD7, OsCesA4, and OsCesA7, were also down-regulated under higher nitrogen conditions at the early stage of culm growth. These results suggest that the genes involved in lignin biosynthesis are down-regulated by higher nitrogen fertilizer, which causes lignin deficiency in the secondary cell walls and the weakening of mechanical tissue structure. Subsequently, this results in these internodes with reduced mechanical strength and poor lodging resistance.

  3. Improving the nutritional value of Golden Rice through increased pro-vitamin A content.

    Science.gov (United States)

    Paine, Jacqueline A; Shipton, Catherine A; Chaggar, Sunandha; Howells, Rhian M; Kennedy, Mike J; Vernon, Gareth; Wright, Susan Y; Hinchliffe, Edward; Adams, Jessica L; Silverstone, Aron L; Drake, Rachel

    2005-04-01

    "Golden Rice" is a variety of rice engineered to produce beta-carotene (pro-vitamin A) to help combat vitamin A deficiency, and it has been predicted that its contribution to alleviating vitamin A deficiency would be substantially improved through even higher beta-carotene content. We hypothesized that the daffodil gene encoding phytoene synthase (psy), one of the two genes used to develop Golden Rice, was the limiting step in beta-carotene accumulation. Through systematic testing of other plant psys, we identified a psy from maize that substantially increased carotenoid accumulation in a model plant system. We went on to develop "Golden Rice 2" introducing this psy in combination with the Erwinia uredovora carotene desaturase (crtI) used to generate the original Golden Rice. We observed an increase in total carotenoids of up to 23-fold (maximum 37 microg/g) compared to the original Golden Rice and a preferential accumulation of beta-carotene.

  4. Introduction of cryIB-cryIAa Hybrid Gene Into Rice (Oryza sativa Genom cv. Rojolele using Agrobacterium-Mediated Transformation

    Directory of Open Access Journals (Sweden)

    SYAMSIDAH RAHMAWATI

    2006-03-01

    Full Text Available Rojolele is one of Indonesian local variety from Javanica group that susceptible to yellow stem borer (Scirpophaga incertulas. Previous study showed that Rojolele can be cultured and regenerated in vitro. Two cry genes, cryIB-cryIAa were fused and introduced into rice cv. Rojolele in an attempt to improve resistance and to obtain durable resistance rice against the yellow stem borer. Two-week old embryogenic calli of Rojolele rice were inoculated with Agrobacterium tumefaciens harbored with binary vector pCAMBIA 1301, 1303, or 1304 carrying cryIB-cryIAa hybrid gene, hygromycin resistant gene (hpt, and -glucuronidase (gus gene interrupted with an intron. The transformed calli were selected gradually on medium containing hygromycin (50, 100 mg/l and regenerated on medium containing 0.5 mg/l IAA and 0.3 mg/l BAP. GUS activity in infected calli was detected by histochemical assay 3 days after inoculation. The highest (100% transformation efficiency were obtained from calli transformed with pCAMBIA 1303 and 1304. Thirty four out of 77 transformed shoots were tested positive for the cryIB-cryIAa gene using PCR analysis. These shoots were grown in the soil to maturity and to collect the seeds. PCR analysis of the T1 progeny revealed that two out of six lines tested showed a Mendelian segregation pattern. These two lines were also potentially resistant to yellow stem borer based on bioassay in planta.

  5. Homology theory on algebraic varieties

    CERN Document Server

    Wallace, Andrew H

    1958-01-01

    Homology Theory on Algebraic Varieties, Volume 6 deals with the principles of homology theory in algebraic geometry and includes the main theorems first formulated by Lefschetz, one of which is interpreted in terms of relative homology and another concerns the Poincaré formula. The actual details of the proofs of these theorems are introduced by geometrical descriptions, sometimes aided with diagrams. This book is comprised of eight chapters and begins with a discussion on linear sections of an algebraic variety, with emphasis on the fibring of a variety defined over the complex numbers. The n

  6. Combined transcriptome and metabolome analyses to understand the dynamic responses of rice plants to attack by the rice stem borer Chilo suppressalis (Lepidoptera: Crambidae).

    Science.gov (United States)

    Liu, Qingsong; Wang, Xingyun; Tzin, Vered; Romeis, Jörg; Peng, Yufa; Li, Yunhe

    2016-12-07

    Rice (Oryza sativa L.), which is a staple food for more than half of the world's population, is frequently attacked by herbivorous insects, including the rice stem borer, Chilo suppressalis. C. suppressalis substantially reduces rice yields in temperate regions of Asia, but little is known about how rice plants defend themselves against this herbivore at molecular and biochemical level. In the current study, we combined next-generation RNA sequencing and metabolomics techniques to investigate the changes in gene expression and in metabolic processes in rice plants that had been continuously fed by C. suppressalis larvae for different durations (0, 24, 48, 72, and 96 h). Furthermore, the data were validated using quantitative real-time PCR. There were 4,729 genes and 151 metabolites differently regulated when rice plants were damaged by C. suppressalis larvae. Further analyses showed that defense-related phytohormones, transcript factors, shikimate-mediated and terpenoid-related secondary metabolism were activated, whereas the growth-related counterparts were suppressed by C. suppressalis feeding. The activated defense was fueled by catabolism of energy storage compounds such as monosaccharides, which meanwhile resulted in the increased levels of metabolites that were involved in rice plant defense response. Comparable analyses showed a correspondence between transcript patterns and metabolite profiles. The current findings greatly enhance our understanding of the mechanisms of induced defense response in rice plants against C. suppressalis infestation at molecular and biochemical levels, and will provide clues for development of insect-resistant rice varieties.

  7. Factors Affecting the Distribution of Wild Rice (Zizania palustris) and the Surrounding Macrophyte Community.

    Science.gov (United States)

    Pillsbury, R. W.; McGuire, M.

    2005-05-01

    A recent decline in wild rice wetlands is cause for concern due to its importance as a food source, refuge for wildlife, and cultural significance. Sixty wetlands in Wisconsin and Minnesota (USA) were sampled, with approximately equal numbers displaying dense, moderate and sparse wild rice production. Chemical, physical, and watershed parameters were measured as well as macrophyte densities. Data were analyzed using multivariate statistics (CCA). Moderate levels of phosphorus appear beneficial to the overall success of wild rice, while free-floating macrophytes show an overwhelming positive response to higher levels of P. The distribution of macrophytes bordering wild rice beds is correlated to pH,with Potamogeton robbinsii and filamentous green algae responding most strongly to its increase. Healthy stands of wild rice exhibit a narrow circum-neutral range of pH (6.1-8.0)which is significantly different from the greater range exhibited by sparse wild rice wetlands (6.5-8.5). This pattern was paralleled when considering depth which suggests that deeper wetlands may be more susceptible to wild rice loss. Management of existing wild rice wetlands should focus monitoring on pH, depth, phosphorus concentrations and shore development. We are currently using this data base to locate the best reintroduction sites for wild rice.

  8. Characteristics of phenotype and genetic mutations in rice after spaceflight

    Science.gov (United States)

    Yu, X.; Wu, H.; Wei, L. J.; Cheng, Z. L.; Xin, P.; Huang, C. L.; Zhang, K. P.; Sun, Y. Q.

    To investigate the mechanism of spaceflight induced mutations, seeds of 11 pure rice varieties carried by Shenzhou-3 spaceship of China in 2002 for six-day flight were planted and investigated. Results showed that mutations could be induced in the first generation (M 1). Five tall mutants were found in DongnongV7 variety, and the average height of the mutants was 31% taller than that of the control. Other traits such as the panicle length were also remarkably different from the control. In the second generation (M 2), various changes of traits were observed in all 11 varieties, including the height, heading date, leaf color, leaf shape, flag leaf angle, awns, panicle length, panicle type, rice shape (length-width ratio), and maturity. The mutation rate for the changes of the plant height and of the rice color (purple) varied from 0.05% to 0.52% among ten varieties except Xixuan-1. Changes of the height, fresh weight, dry weight, and culm width of the five DongnongV7 tall mutants were observed in the progeny individually. By using the AFLP (amplified fragment length polymorphism) method, 21 pairs of primers were employed and the mutated loci rate of the genome in 10 M 2 mutants from 10 varieties was found between 1.7% and 6.2%. In the third generation (M 3), many traits, such as the awn length, main panicle exertion date and plant height, were still segregated widely and diversely. In addition, the leaf color and awn color varied in the progenies of purple rice mutants. Our study suggested that spaceflight induced mutations were dependent on different rice varieties.

  9. The effects of chilling stress after anthesis on the physicochemical properties of rice (Oryza sativa L) starch.

    Science.gov (United States)

    Zhu, Dawei; Wei, Haiyan; Guo, Baowei; Dai, Qigen; Wei, Cunxu; Gao, Hui; Hu, Yajie; Cui, Peiyuan; Li, Min; Huo, Zhongyang; Xu, Ke; Zhang, Hongcheng

    2017-12-15

    This study investigates the effect of chilling stress, over a period of three days after anthesis, on the physicochemical properties of starches derived from six rice cultivars. Chilling stress significantly affected the grain characteristics and physicochemical properties of rice starches, except for those of two varieties, NJ 9108 and ZD 18. In the other four rice cultivars subjected to chilling stress, the content of medium, and large sized granules showed a decrease, and an increase, respectively. Amylose content increased as a result of chilling stress, thereby resulting in starch with a lower swelling power, water solubility, and higher retrogradation enthalpy and gelatinization temperature. Chilling stress led to deterioration of cooked rice quality as determined by the pasting properties of starch. This study indicated that among the cultivars studied, the two rice varieties most resistant to chilling stress after rice anthesis were NJ 9108 and ZD 18. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Effects of Polishing on Proximate Composition, Physico- Chemical Characteristics, Mineral Composition and Antioxidant Properties of Pigmented Rice

    Directory of Open Access Journals (Sweden)

    Chagam Koteswara Reddy

    2017-09-01

    Full Text Available The effects of polishing on proximate compositions, physico-chemical characteristics, mineral compositions and antioxidant properties of the rice flours obtained from three different pigmented rice varieties (Chak-hao Angangba, Chak-hao Amubi and Chak-hao Poireiton were investigated. The rice varieties were significantly (P < 0.05 different in the contents of the test characteristics. Lipids, ash, minerals, phytochemicals (phenolic acids and flavonoids and 2,2-diphenyl-1-picrylhydrazyl (DPPH activity of rice flours were decreased after polishing (9% degree of milling, while amylose content and lightness were increased. X-ray diffraction pattern of rice flours exhibited A-type crystalline pattern with reflections at 15.1°, 17.1°, 18.2° and 23.0°. Pasting properties and transition temperatures were decreased after polishing treatment. Polishing resulted in changes in the crystallinity, enthalpy and morphology of rice flours.

  11. Germination potential index of Sindh rice cultivars on biochemical ...

    African Journals Online (AJOL)

    use

    2011-12-14

    Dec 14, 2011 ... Full Length Research Paper. Germination potential index of Sindh ... α-amylase activity is a biochemical indicator showing different germination abilities of rice varieties, leading to different seed vigor. Among ... production of this foreign commodity may be due to many constraints such as poor seed quality, ...

  12. The morphology and bioactivity of the rice field cyanobacterium

    NARCIS (Netherlands)

    Ahmed, M.; Stal, L.; Hasnain, S.

    2014-01-01

    The genus Leptolyngbya comprises filamentous cyanobacteria that are important in rice fields. In the rhizosphere, cyanobacteria produce a variety of secondary metabolites such as auxins that are important in agriculture soil performance. To assess this, Leptolyngbya strain MMG-1, was isolated from

  13. Transgenic strategies for improving rice disease resistance | Zhang ...

    African Journals Online (AJOL)

    Improvement of virus resistance can be achieved by generating transgenic rice lines with expression of genes encoding viral coat protein or replication enzymes, expression of RNA interference constructs and suppression of insect vectors. Varieties with improved resistance against fungal and bacterial pathogens can be ...

  14. Yield Of Edible Pleurotus Mushrooms Grown On Rice Straw With ...

    African Journals Online (AJOL)

    An experiment was conducted to determine the performance of different species of edible Pleurotus mushrooms grown on rice straw substrate with and without chicken manure supplementation. The Pleurotus species /varieties tested were P. flabellatus of Tanzania, India and Thailand origin, and P. sajor caju from Tanzania ...

  15. Technical Efficiency Of Rice Farmers In Ebonyi State, Nigeria ...

    African Journals Online (AJOL)

    Credit, education, farming experience, farm size, membership of farmer\\'s associations/cooperative society, use of improved rice varieties, extension contact, system of production, and timeliness of farm operations were found to be positively and significantly related to technical efficiency. The study found no relationship ...

  16. Peasant rice agriculture: Its character and mechanisms of genetic ...

    African Journals Online (AJOL)

    The factors implicated in the genetic erosion of peasant rice germplasm are; mode of harvesting, inherent population dynamics like choking up of late emergents, loss of lodging and shattering genotypes, loss of late-maturing genotypes, seed dormancy. Wholesale loss due to adoption of improved varieties and complete ...

  17. The Cost of Delaying Approval of Golden Rice

    NARCIS (Netherlands)

    Wesseler, J.H.H.; Kaplan, S.; Zilberman, D.

    2014-01-01

    More than 250,000 children go blind every year because of Vitamin A deficiency. Vitamin A intake can be enhanced by consuming Golden Rice—a genetically engineered variety of rice. It was available for commercialization in 2002, but approval has been delayed. We estimate that this delay has resulted

  18. The Cost of Delaying Approval of Golden Rice

    OpenAIRE

    Wesseler, J.H.H.; Kaplan, S.; Zilberman, D.

    2014-01-01

    More than 250,000 children go blind every year because of Vitamin A deficiency. Vitamin A intake can be enhanced by consuming Golden Rice—a genetically engineered variety of rice. It was available for commercialization in 2002, but approval has been delayed. We estimate that this delay has resulted in 600,000 to 1.2 million additional cases of blindness.

  19. Adoption of Improved Rice Production Technologies among Youth ...

    African Journals Online (AJOL)

    The study equally indicated that preferences for grains quality and straw yield are some of the reasons for adopting improved rice varieties. Furthermore, income, extension contact and social participation had significant relationship with adoption (p< 0.05). The major constraints identified include pest invasion reported by ...

  20. The morphology and bioactivity of the rice field cyanobacterium Leptolyngbya

    NARCIS (Netherlands)

    Ahmed, M.; Stal, L.J.; Hasnain, S.

    2014-01-01

    The genus Leptolyngbya comprises filamentous cyanobacteria that are important in rice fields. In the rhizosphere, cyanobacteria produce a variety of secondary metabolites such as auxins that are important in agriculture soil performance. To assess this, Leptolyngbya strain MMG-1, was isolated from

  1. Estimation of genetic diversity in rice ( Oryza sativa L. ) genotypes ...

    African Journals Online (AJOL)

    Thirty rice genotypes comprising land races, pure lines, somaclones, breeding lines and varieties specifically adapted to costal saline environments were characterized by SSR markers and morphological characters in this study. Out of 35 primers of SSR markers, 28 were found to be polymorphic. The PIC value ranged ...

  2. Determinants of molecular marker based classification of rice (Oryza ...

    African Journals Online (AJOL)

    mr devi singh

    2015-01-07

    Jan 7, 2015 ... The genomic DNA of 44 rice varieties was isolated using CTAB method (Moller et al., 1992). 10. ISSR and 28 SSR molecular markers (Table 4) were used for genetic analysis. The ISSR-PCR technique (Zietkiewicz et al.,. 1994) was used to enhance the speed of sensitivity of detection of molecular markers.

  3. Association analysis of important agronomic traits in japonica rice ...

    African Journals Online (AJOL)

    In this study, a natural population comprising 128 japonica rice varieties was investigated during two years, for eleven important agronomic traits. The population was genotyped using 152 microsatellite markers across the whole genome. A unified mixed linear model was used to identify marker-trait associations, taking into ...

  4. Interference of five problematic weed species with rice growth and ...

    African Journals Online (AJOL)

    Five weed species namely, Cyperus rotundus L., Cyperus difformis L., Echinochloa colonum (L.) Link., Paspalum paspaloides (Mich.) Scribner, and Marsilea minuta L. were selected for the assessment of their level of competition with two commonly grown rice varieties viz. Basmati-385 and Super Basmati. Root and shoot ...

  5. scale rice farmers in nigeria

    African Journals Online (AJOL)

    Admin

    of world rice, with China and India accounting for over half of the world's output. Worldwide, rice production has ... reported that rice indeed is no longer a luxury food in. Nigeria, and that it has become a major source of ... declined in China and Japan but this trend is not observed in other Asian countries; instead, the share ...

  6. Glycaemic and insulin responses, glycaemic index and insulinaemic index values of rice between three Asian ethnic groups.

    Science.gov (United States)

    Tan, V M H; Wu, T; Henry, C J; Lee, Y S

    2015-04-28

    Asians exhibit larger glycaemic response (GR) and insulin response (IR) than Caucasians, predisposing to an increased risk of type 2 diabetes mellitus (T2DM). We aimed to determine the GR and IR as well as the glycaemic index (GI) and insulinaemic index (II) of two rice varieties among three ethnic groups in Singapore. A total of seventy-five healthy males (twenty-five Chinese, twenty-five Malay and twenty-five Asian-Indians) were served the available equivalent carbohydrate amounts (50 g) of test foods (Jasmine rice and Basmati rice) and a reference food (glucose) on separate occasions. Postprandial blood glucose and plasma insulin concentrations were measured at fasting ( -5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min after food consumption. Using the trapezoidal rule, GR, IR, GI and II values were determined. The GR did not differ between ethnic groups for Jasmine rice and Basmati rice. The IR was consistently higher for Jasmine rice (P=0·002) and Basmati rice (P=0·002) among Asian-Indians, probably due to compensatory hyperinsulinaemia to maintain normoglycaemia. The GI and II of both rice varieties did not differ significantly between ethnicities. The overall mean GI for Jasmine rice and Basmati rice were 91 (sd 21) and 59 (sd 15), respectively. The overall mean II for Jasmine rice was 76 (sd 26) and for Basmati rice was 57 (sd 24). We conclude that the GI values presented for Jasmine rice and Basmati rice were applicable to all three ethnic groups in Singapore. Future studies should include deriving the II for greater clinical utility in the prevention and management of T2DM.

  7. Allelopathy: Potential Role to Achieve New Milestones in Rice Cultivation

    Directory of Open Access Journals (Sweden)

    M.K. Amb

    2016-07-01

    Full Text Available Rice fields are ecosystems with many types of plants, microbes, invertebrates, birds and animals. The rice farming protects the biodiversity of the region and maintains the ecosystem for the benefit of environment. Some rice varieties release biocidal allelochemicals which might affect major weeds, microbial and pathogenic diversity around rice plants, even soil characteristics. A large number of compounds such as phenolic acids, fatty acids, indoles and terpenes have been identified in rice root exudates and decomposing rice residues, as putative allelochemicals which can interact with surrounding environment. Since these allelopathic interactions may be positive, they can be used as effective contributor for sustainable and eco-friendly agro-production system. Genetic modification of crop plants to improve their allelopathic properties and enhancement of desirable traits has been suggested. Development of crops with enhanced allelopathic traits by genetic modification should be done cautiously, keeping in view of the ecological risk assessment (non-toxic and safe for humans and ecosystem, crop productivity, ratio of benefit and cost, etc..

  8. Black rice as a functional food in Indonesia

    Directory of Open Access Journals (Sweden)

    Rarastoeti Pratiwi

    2017-03-01

    Full Text Available There are many local black rice cultivars in Indonesia, yet only a few of these are formally describedin the literature.It has been reportedthat black rice has many phytochemicalvariants which may contribute to its use as a functional food, including nutraceuticals andsecondary metabolites such as anthocyanin, oryzanol,and more.The purpose of this article wasto review literature describing black rice cultivars from Indonesia, with a particular focuson its potential use as a functional food.Our literature search revealed several articles that describe black rice in relation to its nutraceuticalproperties and its role in reducing non-communicable diseases. Other studies describe the diversity of local pigmented rice and its potentialfor lowering the risk of hyperlipidemia,hyperglycemia,and for cancer prevention. Black rice has been described as a functional food in several countries;however,there is great diversity among cultivars and further research on Indonesian varieties will determine whether local variants are candidates as well for the development of functional foods.

  9. A comparison of rice chloroplast genomes

    DEFF Research Database (Denmark)

    Tang, Jiabin; Xia, Hong'ai; Cao, Mengliang

    2004-01-01

    Using high quality sequence reads extracted from our whole genome shotgun repository, we assembled two chloroplast genome sequences from two rice (Oryza sativa) varieties, one from 93-11 (a typical indica variety) and the other from PA64S (an indica-like variety with maternal origin of japonica...... to intersubspecific polymorphisms. In our study, we found that the intersubspecific variations of 93-11 (indica) and PA64S (japonica) chloroplast genomes consisted of 72 single nucleotide polymorphisms and 27 insertions or deletions. The intersubspecific polymorphism rates between 93-11 and PA64S were 0.......05% for single nucleotide polymorphisms and 0.02% for insertions or deletions, nearly 8 and 10 times lower than their respective nuclear genomes. Based on the total number of nucleotide substitutions between the two chloroplast genomes, we dated the divergence of indica and japonica chloroplast genomes...

  10. Dark septate endophyte decreases stress on rice plants

    Directory of Open Access Journals (Sweden)

    Silvana Gomes dos Santos

    Full Text Available Abstract Abiotic stress is one of the major limiting factors for plant development and productivity, which makes it important to identify microorganisms capable of increasing plant tolerance to stress. Dark septate endophytes can be symbionts of plants. In the present study, we evaluated the ability of dark septate endophytes isolates to reduce the effects of water stress in the rice varieties Nipponbare and Piauí. The experiments were performed under gnotobiotic conditions, and the water stress was induced with PEG. Four dark septate endophytes were isolated from the roots of wild rice (Oryza glumaepatula collected from the Brazilian Amazon. Plant height as well as shoot and root fresh and dry matter were measured. Leaf protein concentrations and antioxidant enzyme activity were also estimated. The dark septate endophytes were grown in vitro in Petri dishes containing culture medium; they exhibited different levels of tolerance to salinity and water stress. The two rice varieties tested responded differently to inoculation with dark septate endophytes. Endophytes promoted rice plant growth both in the presence and in the absence of a water deficit. Decreased oxidative stress in plants in response to inoculation was observed in nearly all inoculated treatments, as indicated by the decrease in antioxidant enzyme activity. Dark septate endophytes fungi were shown to increase the tolerance of rice plants to stress caused by water deficiency.

  11. Ambit determination method in estimating rice plant population density

    Directory of Open Access Journals (Sweden)

    Abu Bakar, B.,

    2017-11-01

    Full Text Available Rice plant population density is a key indicator in determining the crop setting and fertilizer application rate. It is therefore essential that the population density is monitored to ensure that a correct crop management decision is taken. The conventional method of determining plant population is by manually counting the total number of rice plant tillers in a 25 cm x 25 cm square frame. Sampling is done by randomly choosing several different locations within a plot to perform tiller counting. This sampling method is time consuming, labour intensive and costly. An alternative fast estimating method was developed to overcome this issue. The method relies on measuring the outer circumference or ambit of the contained rice plants in a 25 cm x 25 cm square frame to determine the number of tillers within that square frame. Data samples of rice variety MR219 were collected from rice plots in the Muda granary area, Sungai Limau Dalam, Kedah. The data were taken at 50 days and 70 days after seeding (DAS. A total of 100 data samples were collected for each sampling day. A good correlation was obtained for the variety of 50 DAS and 70 DAS. The model was then verified by taking 100 samples with the latching strap for 50 DAS and 70 DAS. As a result, this technique can be used as a fast, economical and practical alternative to manual tiller counting. The technique can potentially be used in the development of an electronic sensing system to estimate paddy plant population density.

  12. Dark septate endophyte decreases stress on rice plants.

    Science.gov (United States)

    Santos, Silvana Gomes Dos; Silva, Paula Renata Alves da; Garcia, Andres Calderin; Zilli, Jerri Édson; Berbara, Ricardo Luis Louro

    Abiotic stress is one of the major limiting factors for plant development and productivity, which makes it important to identify microorganisms capable of increasing plant tolerance to stress. Dark septate endophytes can be symbionts of plants. In the present study, we evaluated the ability of dark septate endophytes isolates to reduce the effects of water stress in the rice varieties Nipponbare and Piauí. The experiments were performed under gnotobiotic conditions, and the water stress was induced with PEG. Four dark septate endophytes were isolated from the roots of wild rice (Oryza glumaepatula) collected from the Brazilian Amazon. Plant height as well as shoot and root fresh and dry matter were measured. Leaf protein concentrations and antioxidant enzyme activity were also estimated. The dark septate endophytes were grown in vitro in Petri dishes containing culture medium; they exhibited different levels of tolerance to salinity and water stress. The two rice varieties tested responded differently to inoculation with dark septate endophytes. Endophytes promoted rice plant growth both in the presence and in the absence of a water deficit. Decreased oxidative stress in plants in response to inoculation was observed in nearly all inoculated treatments, as indicated by the decrease in antioxidant enzyme activity. Dark septate endophytes fungi were shown to increase the tolerance of rice plants to stress caused by water deficiency. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  13. Dietary rice bran promotes resistance to Salmonella enterica serovar Typhimurium colonization in mice

    Directory of Open Access Journals (Sweden)

    Kumar Ajay

    2012-07-01

    Full Text Available Abstract Background Dietary rice bran consists of many bioactive components with disease fighting properties; including the capacity to modulate the gut microbiota. Studies point to the important roles of the gut microbiota and the mucosal epithelium in the establishment of protection against enteric pathogens, such as Salmonella. The ability of rice bran to reduce the susceptibility of mice to a Salmonella infection has not been previously investigated. Therefore, we hypothesized that the incorporation of rice bran into the diet would inhibit the colonization of Salmonella in mice through the induction of protective mucosal responses. Results Mice were fed diets containing 0%, 10% and 20% rice bran for one week prior to being orally infected with Salmonella enterica serovar Typhimurium. We found that mice consuming the 10 and 20% rice bran diets exhibited a reduction in Salmonella fecal shedding for up to nine days post-infection as compared to control diet fed animals (p Lactobacillus spp. in rice bran fed mice (p Salmonella entry into mouse small intestinal epithelial cells. Conclusions Increasing rice bran consumption represents a novel dietary means for reducing susceptibility to enteric infection with Salmonella and potentially via induction of native Lactobacillus spp.

  14. Antioxidant Defense Mechanisms of Salinity Tolerance in Rice Genotypes

    Directory of Open Access Journals (Sweden)

    Mohammad Golam Kibria

    2017-05-01

    Full Text Available In order to elucidate the role of antioxidant responses in salinity tolerance in rice genotypes under salt stress, experiments were conducted using four rice varieties, including salt-sensitive BRRI dhan 28 and three salt-tolerant varieties BRRI dhan 47, BINA dhan 8 and BINA dhan 10. Thirty-day-old rice seedlings were transplanted into pots. At the active tillering stage (35 d after transplanting, plants were exposed to different salinity levels (0, 20, 40 and 60 mmol/L NaCl. Salt stress caused a significant reduction in growth for all the rice genotypes. Growth reduction was higher in the salt-sensitive genotype than in the salt-tolerant ones, and BINA dhan 10 showed higher salt tolerance in all measured physiological parameters. The reduction in shoot and root biomass was found to be minimal in BINA dhan 10. Chlorophyll content significantly decreased under salt stress except for BINA dhan 10. Proline content significantly increased in salt-tolerant rice genotypes with increased salt concentration, and the highest proline content was obtained from BINA dhan 10 under salt stress. Catalase and ascorbate peroxidase activities significantly decreased in salt-sensitive genotype whereas significantly increased in salt-tolerant ones with increasing salt concentration. However, salt stress significantly decreased guaiacol peroxidase activity in all the rice genotypes irrespective of salt tolerance. K+/Na+ ratio also significantly decreased in shoots and roots of all the rice genotypes. The salt-tolerant genotype BINA dhan 10 maintained higher levels of chlorophyll and proline contents as well as catalase and ascorbate peroxidase activities under salt stress, thus, this might be the underlying mechanism for salt tolerance.

  15. Super Rice Cropping Will Enhance Rice Yield and Reduce CH4 Emission: A Case Study in Nanjing, China

    Directory of Open Access Journals (Sweden)

    Yu JIANG

    2013-11-01

    Full Text Available A pot experiment was performed to learn the differences in plant productivity and CH4 emission between two rice cultivars, super rice variety Ningjing 1 and traditional variety Zhendao 11, which were currently commercially applied in Nanjing, China. Similar seasonal changes of CH4 emission fluxes and soil solution CH4 contents were found between the tested cultivars. Although there was no significant difference in plant biomass production between the cultivars, the grain yield of Ningjing 1 was significantly higher by 35.0% (P < 0.05 than that of Zhendao 11, whereas the total CH4 emission from Ningjing 1 was 35.2% lower (P < 0.05. The main difference in the amounts of CH4 emission between the cultivars occurred in the period from the tillering stage to the heading stage. The biomass-scaled and yield-scaled CH4 emissions were respectively 3.8 and 5.2 mg/g for Ningjing 1, significantly lower than those for Zhendao 11 (7.4 and 12.8 mg/g, respectively. According to the relationships between the plant growth characteristics and the CH4 emission, a stronger root system contributed mainly to the lower CH4 emission of Ningjing 1, as compared with Zhendao 11. Our results demonstrated that super rice has advantages not only in grain productivity but also in CH4 emission mitigation. Further expansion of super rice cropping will enhance rice yield and reduce greenhouse gas emission in China.

  16. Evolution of Compatibility Range in the Rice-Magnaporthe oryzae System: An Uneven Distribution of R Genes Between Rice Subspecies.

    Science.gov (United States)

    Gallet, Romain; Fontaine, Colin; Bonnot, François; Milazzo, Joëlle; Tertois, Christophe; Adreit, Henri; Ravigné, Virginie; Fournier, Elisabeth; Tharreau, Didier

    2016-04-01

    Efficient strategies for limiting the impact of pathogens on crops require a good understanding of the factors underlying the evolution of compatibility range for the pathogens and host plants, i.e., the set of host genotypes that a particular pathogen genotype can infect and the set of pathogen genotypes that can infect a particular host genotype. Until now, little is known about the evolutionary and ecological factors driving compatibility ranges in systems implicating crop plants. We studied the evolution of host and pathogen compatibility ranges for rice blast disease, which is caused by the ascomycete Magnaporthe oryzae. We challenged 61 rice varieties from three rice subspecies with 31 strains of M. oryzae collected worldwide from all major known genetic groups. We determined the compatibility range of each plant variety and pathogen genotype and the severity of each plant-pathogen interaction. Compatibility ranges differed between rice subspecies, with the most resistant subspecies selecting for pathogens with broader compatibility ranges and the least resistant subspecies selecting for pathogens with narrower compatibility ranges. These results are consistent with a nested distribution of R genes between rice subspecies.

  17. Effects of Organic and Conventional Cropping Systems on Technological Properties and Phenolic Compounds of Freshly Harvested and Stored Rice.

    Science.gov (United States)

    Alves, Gabriela Hörnke; Paraginski, Ricardo Tadeu; Lamas, Nelisa de Souza; Hoffmann, Jessica Fernanda; Vanier, Nathan Levien; de Oliveira, Maurício

    2017-10-01

    This study compared the physicochemical and technological properties of the IRGA 410 rice cultivar, obtained from organic and conventional cropping systems, and showed its susceptibility to changes during storage at 0, 6, and 12 mo. The rice conventional cropping system exhibited greater protein, lipids, and ash levels, and a head rice yield. However, organic rice presented greater total carbohydrates, soluble protein, amylose content, 33% greater free phenolics, and phenolic acids, but exhibited a greater percentage of stained grains during the storage period. The free phenolic content of cooked rice was lower than the free phenolic content of the raw rice. By Liquid chromatography with mass spectrometer (LC-MS) were identified p-coumaric and ferulic acids in both fractions (free and bound). The content of p-coumaric acid and ferulic acid in bound fraction was higher in organic brown rice than in conventional brown rice. At 6 and 12 mo of storage, the main fungi found were Aspergillus sp. and Penicillium sp. Prior to storage, the Bipolaris sp. fungi was identified only in organic rice. For conventional rice, the infestation level by Aspergillus sp. increased from 3% to 70% at the 6th mo of storage. In addition to the advantage of organic rice being free of agrochemicals, this study revealed that natural plant defense compounds could be produced when the rice was subjected to more biotic and abiotic stresses. However, some disadvantages were observed, such as lower protein content and a greater percentage of soluble protein, which favored the breaking of rice in processing, and a greater percentage of grain stained before and during storage. The organic and conventional cropping systems affect the physicochemical and technological properties of rice grains, which is one of the main cereals grown and consumed in the world. This study shows the advantages and disadvantages of the cropping system in grain properties that are in the interest of both consumers and

  18. Microsatellite genotyping of carnation varieties

    NARCIS (Netherlands)

    Smulders, M.J.M.; Noordijk, Y.; Rus-Kortekaas, W.; Bredemeijer, G.M.M.; Vosman, B.

    2003-01-01

    A set of 11 sequence-tagged microsatellite markers for carnation (Dianthus caryophyllus) was developed using a DNA library enriched for microsatellites. Supplemented with three markers derived from sequence database entries, these were used to genotype carnation varieties using a semi-automated

  19. Aphid resistance in wheat varieties.

    Science.gov (United States)

    Elek, Henriett; Werner, Peter; Smart, Lesley; Gordon-Weeks, Ruth; Nádasy, Miklós; Pickett, John

    2009-01-01

    As an environmentally compatible alternative to the use of conventional insecticides to control cereal aphids, we have investigated the possibility to exploit natural resistance to insect pests in wheat varieties. We have tested a wide range of hexaploid (Triticum aestivum), tetraploid (T. durum) and diploid (T. boeoticum and T. monococcum) wheat lines for resistance to the bird cherry oat aphid (Rhopalosiphum padi). Lines tested included Russian wheat aphid (Diuraphis noxia), greenbug (Schizaphis graminum), hessian fly (Mayetiola destructor) and orange wheat blossom midge (Sitodiplosis mosellana) resistant varieties. Antixenosis and antibiosis were determined in the settling and fecundity tests respectively. Since hydroxamic acids (Hx), including the most generally active, 2,4-dihidroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), are biosynthesised in many cereal plants and are implicated in resistance against insects, leaf tissue was analysed for Hx and the glucosides from which they are produced. The hexaploid varieties, which contained relatively low levels of the DIMBOA glucoside, did not deter aphid feeding or reduce nymph production significantly. Reduced settlement and nymph production were recorded on the diploid varieties, but they contained no detectable level of the glucoside or the toxic aglucone.

  20. Genetic Transformation of Rice with Pi-d2 Gene Enhances Resistance to Rice Blast Fungus Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    De-xi CHEN

    2010-03-01

    Full Text Available The gene Pi-d2, conferring gene-for-gene resistance to the Chinese blast strain ZB15, was isolated from a rice variety (Digu by the map-based cloning strategy. Here, we constructed a control plasmid pZH01-pi-d2tp309 (pZH01-tp309 and three different expression constructs, pCB-Pi-d2 5.3kb (pCB5.3kb, pCB-Pi-d26.3kb (pCB6.3kb and pZH01-Pi-d22.72kb (pZH01-2.72kb of Pi-d2, driven by Pi-d2 gene's own promoter or CaMV35S promoter. These constructs were separately introduced into japonica rice varieties Lijiangxintuanhegu, Taipei 309, Nipponbare and Zhonghua 9 through Agrobacterium-mediated transformation. A total of 150 transgenic rice plants were obtained from the regenerated calli selected on hygromycin. PCR, RT-PCR and Southern-blotting assay showed that the gene of interest had been integrated into rice genome and stably inherited. Thirty-five transgenic lines independently derived from T1 progeny were inoculated with the rice blast strain ZB15. Transformants exhibited resistance to rice blast at various levels. The lesions on the transgenic plant leaves were less severe than those on the controls and the resistance level of transgenic plants harboring the gene of interest from three vectors had no difference. The own promoter of Pi-d2, about 2.2 kb or 3.2 kb, had the similar promoter function as CaMV35S. Field evaluation for three successive years supported the results of artificial trial, and some lines with high resistance to rice leaf blast and neck blast were obtained.

  1. Classification of Irregular Varieties : Minimal Models and Abelian Varieties

    CERN Document Server

    Catanese, Fabrizio; Ciliberto, Ciro

    1992-01-01

    M. Andreatta,E.Ballico,J.Wisniewski: Projective manifolds containing large linear subspaces; - F.Bardelli: Algebraic cohomology classes on some specialthreefolds; - Ch.Birkenhake,H.Lange: Norm-endomorphisms of abelian subvarieties; - C.Ciliberto,G.van der Geer: On the jacobian of ahyperplane section of a surface; - C.Ciliberto,H.Harris,M.Teixidor i Bigas: On the endomorphisms of Jac (W1d(C)) when p=1 and C has general moduli; - B. van Geemen: Projective models of Picard modular varieties; - J.Kollar,Y.Miyaoka,S.Mori: Rational curves on Fano varieties; - R. Salvati Manni: Modular forms of the fourth degree; A. Vistoli: Equivariant Grothendieck groups and equivariant Chow groups; - Trento examples; Open problems

  2. Draft Genome Sequence of the Plant Pathogen Dickeya zeae DZ2Q, Isolated from Rice in Italy.

    Science.gov (United States)

    Bertani, Iris; Passos da Silva, Daniel; Abbruscato, Pamela; Piffanelli, Pietro; Venturi, Vittorio

    2013-11-07

    Dickeya zeae is an emerging rice (Oryza sativa) pathogen causing bacterial foot rot. Related pathogens affect maize (Zea mays) and potato (Solanum tuberosum) and a variety of important ornamental and floral plants. Here, we present the draft genome sequence of D. zeae DZ2Q, an isolate obtained from rice grown in Italy.

  3. Draft Genome Sequence of the Plant Pathogen Dickeya zeae DZ2Q, Isolated from Rice in Italy

    OpenAIRE

    Bertani, Iris; Passos da Silva, Daniel; Abbruscato, Pamela; Piffanelli, Pietro; Venturi, Vittorio

    2013-01-01

    Dickeya zeae is an emerging rice (Oryza sativa) pathogen causing bacterial foot rot. Related pathogens affect maize (Zea mays) and potato (Solanum tuberosum) and a variety of important ornamental and floral plants. Here, we present the draft genome sequence of D. zeae DZ2Q, an isolate obtained from rice grown in Italy.

  4. Protein fingerprint diversification of rice seeds

    Science.gov (United States)

    Lu, Weihong; Sun, Yeqing; Zheng, Qi; Guan, Shuanghong

    To study protein fingerprint diversification of rice seeds induced by space environment we selected three series mutants induced in Chinese recoverable satellite in 1996 for 15 days including 1 Series 971 971ck the control sample in ground 971-5 and 971-4 samples after space derivation 2 Series 972 972ck the control sample in ground 972-4 and 972-1 samples after space derivation 3 Series 974 974ck the control sample in ground 974-5 and 974-8 samples after space derivation The proteins were extracted and separated to 4 groups Albumin Globulin Prolamine and Glutelin from the seeds of ground control group and inducted by space environment group Using RPLC method Reference peak was selected in every group and its relative retention time was 1 000 The relative retention time of other peaks was the ratio Calculate the contents due to the peak areas and draw a conclusion that some contents of protein were changed in the seeds of the mutant varieties There are character peaks among different varieties as the fingerprint Comparative analysis the fingerprint of Albumin Globulin and Prolamine can find the different in varieties identify The protein express abundance and easy be detected in the seeds So using RPLC method the Protein Fingerprint can identify breed handily and steadily Keywords rice seeds Space environment Protein Fingerprint

  5. A high-density SNP genotyping array for rice biology and molecular breeding.

    Science.gov (United States)

    Chen, Haodong; Xie, Weibo; He, Hang; Yu, Huihui; Chen, Wei; Li, Jing; Yu, Renbo; Yao, Yue; Zhang, Wenhui; He, Yuqing; Tang, Xiaoyan; Zhou, Fasong; Deng, Xing Wang; Zhang, Qifa

    2014-03-01

    A high-density single nucleotide polymorphism (SNP) array is critically important for geneticists and molecular breeders. With the accumulation of huge amounts of genomic re-sequencing data and available technologies for accurate SNP detection, it is possible to design high-density and high-quality rice SNP arrays. Here we report the development of a high-density rice SNP array and its utility. SNP probes were designed by screening more than 10 000 000 SNP loci extracted from the re-sequencing data of 801 rice varieties and an array named RiceSNP50 was produced on the Illumina Infinium platform. The array contained 51 478 evenly distributed markers, 68% of which were within genic regions. Several hundred rice plants with parent/F1 relationships were used to generate a high-quality cluster file for accurate SNP calling. Application tests showed that this array had high genotyping accuracy, and could be used for different objectives. For example, a core collection of elite rice varieties was clustered with fine resolution. Genome-wide association studies (GWAS) analysis correctly identified a characterized QTL. Further, this array was successfully used for variety verification and trait introgression. As an accurate high-throughput genotyping tool, RiceSNP50 will play an important role in both functional genomics studies and molecular breeding.

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

    Directory of Open Access Journals (Sweden)

    Jing FU

    2012-09-01

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

  7. THE EFFECT OF HEATING ON PHYSICOCHEMICAL CHARACTERISTICS OF RICE BRAND OIL

    Directory of Open Access Journals (Sweden)

    S. Dewi Indrasari

    2016-10-01

    Full Text Available Rice bran oil has a potential in lowering blood cholesterol. The oil content extracted from rice bran isa influenced by several factors such as raw material and processing method. This research was conducted to study the effect of heating on the physicochemical characteristics of rice bran oil. The study was carried out at the Food Technology and Nutrition Laboratory and Biotechnological Science Laboratory of the Inter University Center, Bogor Agricultural University, from February to MAy 1997. Bran used was from IR64 rice variety obtained from a local milling rice in Tambak Dahan, Binong-Subang, West Java. Rice bran was subjected to different period of heating (0, 15 and 30 minutes at 121oC by using an autoclave, then the oil was extraxted by using hexane solvent followed by standard processing at room temperature (28-30oC and 40oC for two hours. The parameters observed were oil content and its quality such as saponification, iodine, acid, peroxide, tiobarbituric acid, and triglyceric acid values as well as oil color. The results showed that oil extracted from rice bran was high, ranging from 9.65 to 11.02%. Heating (sterilizing of the rice bran for 15 and 30 minutes at 120oC proir to extraction increased the oil content. The Quality of rice bran oil extracted met the standard of AOAC.

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

    Science.gov (United States)

    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.

  9. Development of 25 near-isogenic lines (NILs) with ten BPH resistance genes in rice (Oryza sativa L.): production, resistance spectrum, and molecular analysis.

    Science.gov (United States)

    Jena, Kshirod K; Hechanova, Sherry Lou; Verdeprado, Holden; Prahalada, G D; Kim, Sung-Ryul

    2017-11-01

    A first set of 25 NILs carrying ten BPH resistance genes and their pyramids was developed in the background of indica variety IR24 for insect resistance breeding in rice. Brown planthopper (Nilaparvata lugens Stal.) is one of the most destructive insect pests in rice. Development of near-isogenic lines (NILs) is an important strategy for genetic analysis of brown planthopper (BPH) resistance (R) genes and their deployment against diverse BPH populations. A set of 25 NILs with 9 single R genes and 16 multiple R gene combinations consisting of 11 two-gene pyramids and 5 three-gene pyramids in the genetic background of the susceptible indica rice cultivar IR24 was developed through marker-assisted selection. The linked DNA markers for each of the R genes were used for foreground selection and confirming the introgressed regions of the BPH R genes. Modified seed box screening and feeding rate of BPH were used to evaluate the spectrum of resistance. BPH reaction of each of the NILs carrying different single genes was variable at the antibiosis level with the four BPH populations of the Philippines. The NILs with two- to three-pyramided genes showed a stronger level of antibiosis (49.3-99.0%) against BPH populations compared with NILs with a single R gene NILs (42.0-83.5%) and IR24 (10.0%). Background genotyping by high-density SNPs markers revealed that most of the chromosome regions of the NILs (BC3F5) had IR24 genome recovery of 82.0-94.2%. Six major agronomic data of the NILs showed a phenotypically comparable agronomic performance with IR24. These newly developed NILs will be useful as new genetic resources for BPH resistance breeding and are valuable sources of genes in monitoring against the emerging BPH biotypes in different rice-growing countries.

  10. [Testing of germination rate of hybrid rice seeds based on near-infrared reflectance spectroscopy].

    Science.gov (United States)

    Li, Yi-nian; Jiang, Dan; Liu, Ying-ying; Ding, Wei-min; Ding, Qi-shuo; Zha, Liang-yu

    2014-06-01

    Germination rate of rice seeds was measured according to technical stipulation of germination testing for agricultural crop seeds at present. There existed many faults for this technical stipulation such as long experimental period, more costing and higher professional requirement. A rapid and non-invasive method was put forward to measure the germination rate of hybrid rice seeds based on near-infrared reflectance spectroscopy. Two varieties of hybrid rice seeds were aged artificially at temperature 45 degrees C and humidity 100% condition for 0, 24, 48, 72, 96, 120 and 144 h. Spectral data of 280 samples for 2 varieties of hybrid rice seeds with different aging time were acquired individually by near-infrared spectra analyzer. Spectral data of 280 samples for 2 varieties of hybrid rice seeds were randomly divided into calibration set (168 samples) and prediction set (112 samples). Gormination rate of rice seed with different aging time was tested. Regression model was established by using partial least squares (PLS). The effect of the different spectral bands on the accuracy of models was analyzed and the effect of the different spectral preprocessing methods on the accuracy of models was also compared. Optimal model was achieved under the whole bands and by using standardization and orthogonal signal correction (OSC) preprocessing algorithms with CM2000 software for spectral data of 2 varieties of hybrid rice seeds, the coefficient of determination of the calibration set (Rc) and that of the prediction set (Rp) were 0.965 and 0.931 individually, standard error of calibration set (SEC) and that of prediction set (SEP) were 1.929 and 2.899 respectively. Relative error between tested value and predicted value for prediction set of rice seeds is below 4.2%. The experimental results show that it is feasible that rice germination rate is detected rapidly and nondestructively by using the near-infrared spectroscopy analysis technology.

  11. Improving the phenotypic expression of rice genotypes: Rethinking “intensification” for production systems and selection practices for rice breeding

    Directory of Open Access Journals (Sweden)

    Norman Uphoff

    2015-06-01

    Full Text Available Intensification in rice crop production is generally understood as requiring increased use of material inputs: water, inorganic fertilizers, and agrochemicals. However, this is not the only kind of intensification available. More productive crop phenotypes, with traits such as more resistance to biotic and abiotic stresses and shorter crop cycles, are possible through modifications in the management of rice plants, soil, water, and nutrients, reducing rather than increasing material inputs. Greater factor productivity can be achieved through the application of new knowledge and more skill, and (initially more labor, as seen from the System of Rice Intensification (SRI, whose practices are used in various combinations by as many as 10 million farmers on about 4 million hectares in over 50 countries. The highest yields achieved with these management methods have come from hybrids and improved rice varieties, confirming the importance of making genetic improvements. However, unimproved varieties are also responsive to these changes, which induce better growth and functioning of rice root systems and more abundance, diversity, and activity of beneficial soil organisms. Some of these organisms as symbiotic endophytes can affect and enhance the expression of rice plants' genetic potential as well as their phenotypic resilience to multiple stresses, including those of climate change. SRI experience and data suggest that decades of plant breeding have been selecting for the best crop genetic endowments under suboptimal growing conditions, with crowding of plants that impedes their photosynthesis and growth, flooding of rice paddies that causes roots to degenerate and forgoes benefits derived from aerobic soil organisms, and overuse of agrochemicals that adversely affect these organisms as well as soil and human health. This review paper reports evidence from research in India and Indonesia that changes in crop and water management can improve the

  12. Monitoring and Management of Imidazolinone-Resistant Red Rice (Oryza sativa L., var. sylvatica in Clearfield® Italian Paddy Rice

    Directory of Open Access Journals (Sweden)

    Laura Scarabel

    2012-12-01

    Full Text Available The introduction in Italy of Clearfield® rice cultivars carrying imidazolinone-resistant traits provides an efficient option to control red rice, a conspecific weed of cultivated rice. However, despite the promulgation of specific guidelines for Clearfield® technology management, imazamox red rice survivors have been reported by farmers. Forty-two fields were monitored in 2010 and 2011 throughout the Piedmont and Lombardy regions and field cases were recorded of herbicides use and agronomic practices. Whole-plant sensitivity to imazamox was assessed and the resistance mechanism was determined by molecular analysis. Twenty-six red rice populations out of 42 were imazamox-resistant and plants of all the resistant populations possess a Ser to Asn substitution at locus 653 of the ALS gene determining the target-site resistance. Farmers frequently grow Clearfield® varieties for more than two consecutive years so increasing the selection pressure exerted by imazamox and favoring the evolution of resistant red rice. To maintain the sustainability of this new technology, a proper management based on crop rotation, utilization of certified seeds and strict control of red rice escapes has to be implemented. More generally, all stakeholders must increase their awareness that the selection pressure exerted by ALS inhibitors in rice cropping system should be reduced.

  13. Neglecting rice milling yield and quality underestimates economic losses from high-temperature stress.

    Directory of Open Access Journals (Sweden)

    Nathaniel B Lyman

    Full Text Available Future increases in global surface temperature threaten those worldwide who depend on rice production for their livelihoods and food security. Past analyses of high-temperature stress on rice production have focused on paddy yield and have failed to account for the detrimental impact of high temperatures on milling quality outcomes, which ultimately determine edible (marketable rice yield and market value. Using genotype specific rice yield and milling quality data on six common rice varieties from Arkansas, USA, combined with on-site, half-hourly and daily temperature observations, we show a nonlinear effect of high-temperature stress exposure on yield and milling quality. A 1 °C increase in average growing season temperature reduces paddy yield by 6.2%, total milled rice yield by 7.1% to 8.0%, head rice yield by 9.0% to 13.8%, and total milling revenue by 8.1% to 11.0%, across genotypes. Our results indicate that failure to account for changes in milling quality leads to understatement of the impacts of high temperatures on rice production outcomes. These dramatic losses result from reduced paddy yield and increased percentages of chalky and broken kernels, which together decrease the quantity and market value of milled rice. Recently published estimates show paddy yield reductions of up to 10% across the major rice-producing regions of South and Southeast Asia due to rising temperatures. The results of our study suggest that the often-cited 10% figure underestimates the economic implications of climate change for rice producers, thus potentially threatening future food security for global rice producers and consumers.

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

    Science.gov (United States)

    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.

  15. Quiver representations and quiver varieties

    CERN Document Server

    Jr, Alexander Kirillov

    2016-01-01

    This book is an introduction to the theory of quiver representations and quiver varieties, starting with basic definitions and ending with Nakajima's work on quiver varieties and the geometric realization of Kac-Moody Lie algebras. The first part of the book is devoted to the classical theory of quivers of finite type. Here the exposition is mostly self-contained and all important proofs are presented in detail. The second part contains the more recent topics of quiver theory that are related to quivers of infinite type: Coxeter functor, tame and wild quivers, McKay correspondence, and representations of Euclidean quivers. In the third part, topics related to geometric aspects of quiver theory are discussed, such as quiver varieties, Hilbert schemes, and the geometric realization of Kac-Moody algebras. Here some of the more technical proofs are omitted; instead only the statements and some ideas of the proofs are given, and the reader is referred to original papers for details. The exposition in the book requ...

  16. The Birth of a Black Rice Gene and Its Local Spread by Introgression

    Science.gov (United States)

    Oikawa, Tetsuo; Maeda, Hiroaki; Oguchi, Taichi; Yamaguchi, Takuya; Tanabe, Noriko; Ebana, Kaworu; Yano, Masahiro; Izawa, Takeshi

    2015-01-01

    The origin and spread of novel agronomic traits during crop domestication are complex events in plant evolution. Wild rice (Oryza rufipogon) has red grains due to the accumulation of proanthocyanidins, whereas most cultivated rice (Oryza sativa) varieties have white grains induced by a defective allele in the Rc basic helix-loop-helix (bHLH) gene. Although the events surrounding the origin and spread of black rice traits remain unknown, varieties with black grains due to anthocyanin accumulation are distributed in various locations throughout Asia. Here, we show that the black grain trait originated from ectopic expression of the Kala4 bHLH gene due to rearrangement in the promoter region. Both the Rc and Kala4 genes activate upstream flavonol biosynthesis genes, such as chalcone synthase and dihydroflavonol-4-reductase, and downstream genes, such as leucoanthocyanidin reductase and leucoanthocyanidin dioxygenase, to produce the respective specific pigments. Genome analysis of 21 black rice varieties as well as red- and white-grained landraces demonstrated that black rice arose in tropical japonica and its subsequent spread to the indica subspecies can be attributed to the causal alleles of Kala4. The relatively small size of genomic fragments of tropical japonica origin in some indica varieties indicates that refined introgression must have occurred by natural crossbreeding in the course of evolution of the black trait in rice. PMID:26362607

  17. Accumulation and Transfer of Cadmium, by Indica Rice Cultivars Fujian Province of China

    Science.gov (United States)

    James, B.; Wang, G.

    2016-12-01

    This study was designed to evaluate the accumulating ability of cadmium (Cd) by different Indica rice varieties and to understand the differences in transfer factor in the soil-to-rice grain. A total of 189 crop samples and 189 corresponding soil samples were collected for treatment and chemical analysis. Sixteen (16) Indica rice varieties were selected for this study. Our preliminary results showed that there exist significant differences (pindica rice cultivars).The TFstem-grain among the variety revealed that significant differences (pindica rice variety and cadmium decreases in the pattern: root>stem>leaf>grain in the four cultivars except Te -you 009 that showed similar cadmium content in root and stem. Among the hybrid cultivars Yi -you 673 accumulated the most Cadmium in root, stem, leaf and grain, while Te- you 009 accumulated the least Cadmium in root, whereas the conventional cultivar Jia-fu-zhan accumulated the lowest Cadmium in leaf and grain. Our findings also revealed that the Cadmium concentrations in rice grains were more significantly correlated with the Cadmium in stem, followed by leaf, which reveals that the transfer from stem and leaf to grain may be the determinant steps for Cadmium accumulation in the grains.

  18. Novel Chitinase Gene LOC_Os11g47510 from Indica Rice Tetep Provides Enhanced Resistance against Sheath Blight Pathogen Rhizoctonia solani in Rice

    Directory of Open Access Journals (Sweden)

    Tilak R. Sharma

    2017-04-01

    Full Text Available Sheath blight disease (ShB, caused by the fungus Rhizoctonia solani Kühn, is one of the most destructive diseases of rice (Oryza sativa L., causing substantial yield loss in rice. In the present study, a novel rice chitinase gene, LOC_Os11g47510 was cloned from QTL region of R. solani tolerant rice line Tetep and used for functional validation by genetic transformation of ShB susceptible japonica rice line Taipei 309 (TP309. The transformants were characterized using molecular and functional approaches. Molecular analysis by PCR using a set of primers specific to CaMv 35S promoter, chitinase and HptII genes confirmed the presence of transgene in transgenic plants which was further validated by Southern hybridization. Further, qRT-PCR analysis of transgenic plants showed good correlation between transgene expression and the level of sheath blight resistance among transformants. Functional complementation assays confirmed the effectiveness of the chitinase mediated resistance in all the transgenic TP309 plants with varying levels of enhanced resistance against R. solani. Therefore, the novel chitinase gene cloned and characterized in the present study from the QTL region of rice will be of significant use in molecular plant breeding program for developing sheath blight resistance in rice.

  19. Safety assessment of lepidopteran insect-protected transgenic rice with cry2A* gene.

    Science.gov (United States)

    Zou, Shiying; Huang, Kunlun; Xu, Wentao; Luo, Yunbo; He, Xiaoyun

    2016-04-01

    Numerous genetically modified (GM) crops expressing proteins for insect resistance have been commercialized following extensive testing demonstrating that the foods obtained from them are as safe as that obtained from their corresponding non-GM varieties. In this paper, we report the outcome of safety studies conducted on a newly developed insect-resistant GM rice expressing the cry2A* gene by a subchronic oral toxicity study on rats. GM rice and non-GM rice were incorporated into the diet at levels of 30, 50, and 70% (w/w), No treatment-related adverse or toxic effects were observed based on an examination of the daily clinical signs, body weight, food consumption, hematology, serum biochemistry, and organ weight or based on gross and histopathological examination. These results demonstrate that the GM rice with cry2A* gene is as safe for food as conventional non-GM rice.

  20. Decrease in catalase activity of Folsomia candida fed a Bt rice diet

    DEFF Research Database (Denmark)

    Yuan, Yiyang; Ke, Xin; Chen, Fajun

    2011-01-01

    Here we report the effects of three Bt-rice varieties and their non-Bt conventional isolines on biological traits including survival, reproduction, and the activities of three antioxidant enzymes superoxide dismutase, catalase and peroxidase, in the Collembolan, Folsomia candida. The reproduction...... was significantly lower when fed Kemingdao and Huahui1 than those feeding on their non-GM near-isogenic varieties Xiushui and Minghui63 respectively, this can be explained by the differences of plant compositions depended on variety of rice. The catalase activity of F. candida was significantly lower when fed...

  1. Analysis on Factors Affecting Seedling Establishment in Rice

    Directory of Open Access Journals (Sweden)

    Ju LUO

    2007-03-01

    Full Text Available Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of coleoptile and mesocotyl (long, medium and short were selected by screening the lengths of coleoptile and mesocotyl in 1500 accessions. The seedling establishments of these typical cultivars were compared under the combinations of different sowing depths and flooding durations, and two semi-dwarf varieties (G140, Zhong 96–21 with good seedling establishments and optimum mesocotyl lengths were found. The length of mesocotyl was completely fitted negative binomial distribution and the length of coleoptile was nearly fitted lognormal distribution. Analysis of the relationships among mesocotyl, coleoptile, seeding depth, flooding duration, and their interactions to seedling establishment percentage showed that there existed significant relations among mesocotyl, coleoptile, mesocotyl × coleoptile, seeding depth, flooding duration and mesocotyl × sowing depth in the experiment for seedling establishment.

  2. Management of Rice Fields for Birds during the Non-growing Season

    NARCIS (Netherlands)

    Elphick, Chris S.; Taft, Oriane; Lourenco, Pedro M.

    2010-01-01

    Fields planted with rice (Oryza saliva) are used by a wide variety of bird species during the non-growing season and play an important conservation role in many parts of the world. Management of fields affects the variety and number of birds that use them, and a thorough understanding of these

  3. Evaluation of Tolerance in Sugarbeet Varieties to Dodder

    Directory of Open Access Journals (Sweden)

    F Fallahpour

    2013-10-01

    Full Text Available Dodder is an obligate parasite of many plant families and among dodder species Cuscuta campestris has the most diverse around the world. Extensive infestation to dodder recently has been reported in some sugerbeet production regions of Khorasan provinces. So, in this study greenhouse and field experiments were conducted to test and charachterize the tolerance of commercial sugarbeet varieties to C. campestris. A completely randomized design with five replications and a randomized complete block design with three replications were used for the greenhouse and field experiments, respectively. Treatments were five common varieties of sugarbeet included Castille, Paulina, Brigitta, Flores and Laetitia with dodder infestation and control treatments (sugarbeet varieties without infestation. Traits measured were shoot and root dry weight of sugerbeet, dry weight of dodder, the number of houstorium on shoot of sugerbeet, growth percentage of dodder and sugerbeet. The results indicated that varieties showed different levels of tolerance to dodder infection. The variety of Flores had the most percentage of shoot and root dry weight and Paulina with 13.48% of root dry weight and 31.96% of shoot dry weight compared to control showed the least tolerance. Whereas the number of houstorium and dodder dry weight had the most and the least amount in Castille and Flores, respectively. In this experiment Flores variety exhibited tolerance to dodder and Castille was known as susceptible variety.

  4. Accelerated Solvent Extraction of Insecticides from Rice Hulls, Rice Bran, and Polished Rice Grains.

    Science.gov (United States)

    Teló, Gustavo Mack; Senseman, Scott Allen; Marchesan, Enio; Camargo, Edinalvo Rabaioli; Carson, Katherine

    2017-03-01

    Analysis of pesticide residues in irrigated rice grains is important for food security. In this study, we analyzed accelerated solvent extraction (ASE) conditions for the extraction of thiamethoxam and chlorantraniliprole insecticides from rice hulls, rice bran, and polished rice grains. Several variables, including extraction solvent, extraction temperature, extraction pressure, cell size, static extraction time, and sample concentration, were investigated. The average recoveries of the three matrixes were between 89.7 and 109.7% at the fortification level of 0.75 mg/kg. The optimum ASE operating conditions were acetonitrile (100%) as extraction solvent, extraction temperature of 75°C for rice hulls and 100°C for rice bran and polished rice grains, extraction cell pressure of 10.3 MPa, 22 mL cell size, and two extraction cycles. The total extraction time was approximately 25 min. The extracted volume was evaporated to dryness and the residues were redissolved in 2 mL acetonitrile after 1 min of vortex-shaking. Thiamethoxam and chlorantraniliprole were analyzed by ultra-HPLC with tandem MS. In conclusion, ASE in rice hulls, rice bran, and polished rice grains offers the possibility of a fast and simple method for obtaining a quantitative extraction of the studied pesticides.

  5. Algebraic Varieties and System Design

    DEFF Research Database (Denmark)

    Aabrandt, Andreas

    Design and analysis of networks have many applications in the engineering sciences. This dissertation seeks to contribute to the methods used in the analysis of networks with a view towards assisting decision making processes. Networks are initially considered as objects in the category of graphs...... and later as objects in the category of hypergraphs. The connection with the category of simplicial pairs become apparent when the topology is analyzed using homological algebra. A topological ranking is developed that measures the ability of the network to stay path-connected. Combined with the analysis...... are called algebraic varieties....

  6. Varieties of capitalism in crisis?

    DEFF Research Database (Denmark)

    Bruff, Ian; Horn, Laura

    2012-01-01

    In this introduction to the special issue, we provide a brief overview of the two distinct but connected meanings of the phrase ‘varieties of capitalism in crisis’: (1) the crisis of empirical political economies under conditions of capitalist diversity; and (2) the crisis of the institutionalist...... in the special issue, we consider key aspects of what could constitute an alternative conceptual apparatus: uneven development, variegation, and labour. We conclude by calling for greater dialogue and reflexivity across all of the literatures which study capitalist diversity, for we still have much to learn from...

  7. Varieties of Secularism in Asia

    DEFF Research Database (Denmark)

    Varieties of Secularism is an ethnographically rich, theoretically well-informed, and intellectually coherent volume which builds off the work of Talal Asad, Charles Taylor, and others who have engaged the issue of secularism(s) and in socio-political life. The volume seeks to examine theories of...... phenomena; between the new visibilities and silences of magic, ancestors, and religion in democratic politics, this book seeks to outline the particular formations of secularism that have become possible in Asia from China to Indonesia and from Bahrain to Timor-Leste....

  8. Consumers' Preferences for a Local Food Product: The Case of a New Carnaroli Rice Product in Lombardy.

    Science.gov (United States)

    Ferrazzi, Giovanni; Ventura, Vera; Ratti, Sabrina; Balzaretti, Claudia

    2017-04-13

    Italy, with a cultivated area of 218,000 ha, is a European leader of rice production. In particular Lombardy region accounts for 40% of total rice cultivation and the case study in object accounts for 3.2% of Lombardy total rice area (2773 ha). Starting from 2012, through a regional project titled Buono, Sano e Vicino (good, healthy and close), Riso e Rane rural district supported local rice farmers in developing innovation in rice production and promoting an alternative supply chain to increase farmers bargaining power and promote new market strategies. More specifically, the innovation introduced is a new biotech method for variety certification, named DNA controllato (DNA tested). In the first step of the project, the attention was focused on an Italian traditional variety of rice: Carnaroli rice. Thanks to a commercial agreement with one of the most important large retailers in Lombardy, the Riso e Rane rice is offered for sale both in the traditional and wholegrain version. In this context, this work aims to evaluate the determinants of consumer's quality perception of this product, through a preference study of the commercial rice package. Preliminary results reveal that consumers perceive information about origin, local food-system and tradition more easily than DNA tested certification. In conclusion, this work contributes to evaluate the role of bio economy applications to the food sector and offers new insights for the debate about the relationships between tradition and innovation.

  9. Influência da região de plantio do arroz sôbre a infestação da traça dos cereais, Sitotroga cerealella (Olivier (Lepidoptera Gelechiidae Influence of the local of rice planting upon the infestation of Sitotroga cerealella (Olivier (Lepidoptera Gelechidae

    Directory of Open Access Journals (Sweden)

    Carlos Jorge Rossetto

    1969-01-01

    Full Text Available Procurou-se verificar a influência da região e da irrigação na cultura do arroz sôbre a suscetibilidade posterior do grão armazenado ao ataque da traça. Amostras de arroz com casca foram plantadas em quatro regiões diferentes do Estado de São Paulo, em culturas de várzea irrigada e de sequeiro. O produto, armazenado por um ano e meio em ambiente uniforme, foi submetido ao ataque da traça Sitotroga cerealella (Olivier. Foi observado que o local de cultivo do arroz influencia sua suscetibilidade à infestação da traça dos cereais durante o armazenamento. Os resultados mostraram que o arroz cultivado em sequeiro na região de Pindorama foi muito mais atacado pela traça que os cultivados nas outras regiões. O teste de Scheffé mostrou que houve um contraste significativo entre o arroz de várzea de Pindamonhangaba, Campinas e Mococa e o de sequeiro de Pindorama e Campinas, mas não houve diferença significativa entre o arroz de várzea e o de sequeiro de Campinas. O período entre a infestação do arroz em casca, em laboratório, e o início da emergência dos primeiros adultos foi de 23 dias.It was investigated whether or not the local of cultivation of rice affects the posterior susceptibility to Sitotroga cerealella of the grain in storage. Samples of rough rice from the same bulk of seeds, of the variety Dourado Agulha, were planted in four regions of the State of São Paulo, Pindamonhangaba paddy, Pindorama upland, Mococa paddy. Campinas paddy and Campinas upland. The rice, after having been harvested, was taken to Campinas where - after one year and half of storage under uniform conditions for all samples - it was tested for its susceptibility to the insect, by using samples of each local replicated 10 times randomly distributed inside of an insect cage. The progeny of insects of each sample was recorded daily. The trial was repeated twice. The results showed that the local of cultivation has influence upon the posterior

  10. Defining the genome structure of 'Tongil' rice, an important cultivar in the Korean "Green Revolution".

    Science.gov (United States)

    Kim, Backki; Kim, Dong-Gwan; Lee, Gileung; Seo, Jeonghwan; Choi, Ik-Young; Choi, Beom-Soon; Yang, Tae-Jin; Kim, Kwang Soo; Lee, Joohyun; Chin, Joong Hyoun; Koh, Hee-Jong

    2014-12-01

    Tongil (IR667-98-1-2) rice, developed in 1972, is a high-yield rice variety derived from a three-way cross between indica and japonica varieties. Tongil contributed to the self-sufficiency of staple food production in Korea during a period known as the 'Korean Green Revolution'. We analyzed the nucleotide-level genome structure of Tongil rice and compared it to those of the parental varieties. A total of 17.3 billion Illumina Hiseq reads, 47× genome coverage, were generated for Tongil rice. Three parental accessions of Tongil rice, two indica types and one japonica type, were also sequenced at approximately 30x genome coverage. A total of 2,149,991 SNPs were detected between Tongil and Nipponbare varieties. The average SNP frequency of Tongil was 5.77 per kb. Genome composition was determined based on SNP data by comparing Tongil with three parental genome sequences using the sliding window approach. Analyses revealed that 91.8% of the Tongil genome originated from the indica parents and 7.9% from the japonica parent. Copy numbers of SSR motifs, ORF gene distribution throughout the whole genome, gene ontology (GO) annotation, and some yield-related QTLs or gene locations were also comparatively analyzed between Tongil and parental varieties using sequence-based tools. Each genetic factor was transferred from the parents into Tongil rice in amounts that were in proportion to the whole genome composition. Tongil was derived from a three-way cross among two indica and one japonica varieties. Defining the genome structure of Tongil rice demonstrates that the Tongil genome is derived primarily from the indica genome with a small proportion of japonica genome introgression. Comparative gene distribution, SSR, GO, and yield-related gene analysis support the finding that the Tongil genome is primarily made up of the indica genome.

  11. Agrotechnical management to increase yield and quality of rice at a low production cost.

    Directory of Open Access Journals (Sweden)

    Miguel A. Arbolay Moya

    2011-11-01

    3.\tPlot experiments on rice plant nutrition in order to obtain a better grain filling Results showed the bad quality of employed seeds: 53 and 59% of both rice varieties (LP-5 and J-104, respectively presented a poor formation with insufficient grain filling, from which it is impossible to arise normal rice seedlings, as was seen in the observations done, and besides the high number of dead embryos obtained: 13.3 % for variety LP-5 and 33.3% for J-104. Nutrition plots reflected importance on the utilization of fertilizers in adequate moments of life cycle of the rice plant, especially nitrogen, that must be in the early stages of growth and lastly in the reproductive phase; treatment 4, which responded to this management was superior, yielded 11.52 tones of paddy per hectare in 2008-2009 Dry Season and 7.83 in 2009 Wet Season, with statistical difference to all other treatments.

  12. Genetic Diversity Analysis of Iranian Improved Rice Cultivars through RAPD Markers

    Directory of Open Access Journals (Sweden)

    Ghaffar KIANI

    2011-08-01

    Full Text Available The aim of this study was to evaluate the genetic diversity of Iranian improved rice varieties. Sixteen rice varieties of particular interest to breeding programs were evaluated by means of random amplified polymorphic DNA (RAPD technique. The number of amplification products generated by each primer varied from 4 (OPB-04 to 11 (OPD-11 with an average of 8.2 bands per primer. Out of 49 bands, 33 (67.35% were found to be polymorphic for one or more cultivars ranging from 4 to 9 fragments per primer. The size of amplified fragments ranged between 350 to 1800 bp. Pair-wise Nei and Li�s (1979 similarity estimated the range of 0.59 to 0.98 between rice cultivars. Results illustrate the potential of RAPD markers to distinguish improved cultivars at DNA level. The information will facilitate selection of genotypes to serve as parents for effective rice breeding programs in Iran.

  13. The Varieties of Good Design

    DEFF Research Database (Denmark)

    Ylirisku, Salu; Arvola, Mattias

    2017-01-01

    This chapter explores the philosopher and logician Georg Henrik von Wright’s metaethical treatise of the varieties of goodness in the context of design. von Wright investigated the use of notion of ‘good’ in language, and he identified six kinds of goodness: namely utilitarian goodness, instrumen...... as a point of departure for the appraisal of the multifaceted and rela-tional character of the idea of good design and of the values of design.......This chapter explores the philosopher and logician Georg Henrik von Wright’s metaethical treatise of the varieties of goodness in the context of design. von Wright investigated the use of notion of ‘good’ in language, and he identified six kinds of goodness: namely utilitarian goodness......, instrumental goodness, technical goodness, medical goodness, hedonic goodness, and the good of man. We discuss these different kinds of goodness in relation to six design traditions that we identify, namely conceptual design, usability design, engineering design, ergonomics design, experience design...

  14. Latest NS varieties of soybean

    Directory of Open Access Journals (Sweden)

    Vidić Miloš

    2010-01-01

    Full Text Available Results obtained from a network of large-plot trials conducted in 2009 and several previous years have shown that there are a number of newly released NS cultivars of soybean that can be recommended for large-scale commercial growing. We have placed on the market a broad range of new cultivars differing in their growth period duration (maturity groups 000, 00, 0, I, II and other agronomic traits (growing requirements, chemical grain composition, etc.. For the next planting season, we have secured sufficient quantities of top quality seed of both our well-established cultivars and our new releases, including the new early varieties Alisa, Galina and Bečejka, the medium-maturing new cultivars Sava and Diva, and the late-maturing new cultivars Rubin and Idila. We will also have limited quantities of our latest releases available, the varieties Iskra (I, Victoria (I and Trijumf (II. We have recently registered four very early cultivars, Gracija (000, Julija (00, Mercur (00 and Prima (00, all of which are particularly suitable for growing soybean as the second crop. Our recommendation is that the new cultivars be introduced gradually to large-scale production and we are hoping they will become popular with the growers. .

  15. Molecular aspect of good eating quality formation in Japonica rice.

    Directory of Open Access Journals (Sweden)

    Ming-Mao Sun

    Full Text Available The composition of amylopectin is the determinant of rice eating quality under certain threshold of protein content and the ratio of amylose and amylopectin. In molecular biology level, the fine structure of amylopectin is determined by relative activities of starch branching enzyme (SBE, granule-bound starch synthase (GBSS, and soluble starch synthase (SSS in rice grain under the same ADP-Glucose level. But the underlying mechanism of eating quality in molecular biology level remains unclear. This paper reports the differences on major parameters such as SNP and insertion-deletion sites, RNA expressions, and enzyme activities associated with eating quality of japonica varieties. Eight japonica rice varieties with significant differences in various eating quality parameters such as palatability and protein content were used in this experiment. Association analysis between nucleotide polymorphism and eating quality showed that S12 and S13 loci in SBE1, S55 in SSS1, S58 in SSS2A were significantly associated with apparent amylose content, alkali digestion value, setback viscosity, consistency viscosity, pasting temperature, which explained most of the variation in apparent amylose content, setback viscosity, and consistency viscosity; and explained almost all variations in alkali digestion value and pasting temperature. Thirty-five SNPs and insertion-deletions from SBE1, SBE3, GBSS1, SSS1, and SSS2A differentiated high or intermediate palatability rice varieties from low palatability rice varieties. Correlation analysis between enzyme activities and eating quality properties revealed that SBE25 and SSS15/W15 were positively correlated with palatability, whereas GBSS10 and GBSS15 were negatively correlated. Gene expressions showed that SBE1 and SBE3 expressions in high palatability varieties tended to be higher than middle and low palatability varieties. Collectively, SBE1, SBE3, SSS1, and SSS2A, especially SBE1 and SBE3 could improve eating

  16. Nicaragua - Rice and Banana Farmers

    Data.gov (United States)

    Millennium Challenge Corporation — This report is an impact evaluation of two components of the Rural Business Development Program (RBD) in Nicaragua, specifically the components benefitting rice and...

  17. The politics of Golden Rice.

    Science.gov (United States)

    Dubock, Adrian

    2014-07-03

    Genetic knowledge applicable to crop improvement has erupted over the past 60 years, and the techniques of introducing genes from one organism to another have enabled new varieties of crops not achievable by previously available methodologies of crop breeding. Research and particularly development of these GMO-crops to a point where they are useful for growers and consumers in most countries is subject to complex national and international rules arising out of the UN's Cartagena Protocol on Biosafety to the Convention on Biological Diversity, with 167 country signatories. (The USA and Canada are not signatories.) The Protocol was developed based on concerns initially expressed in the 1970's that such technology presented unusual risks to man and the environment. Those ideas have comprehensively and authoritatively been proven to be wrong. The Protocol has nevertheless spawned significant regulatory obstacles to the development of GMO-crop technology at great cost to global society and in conflict with many other UN objectives. The suspicion induced by the Protocol is also widely used, overtly or covertly, for political purposes. These points are illustrated by reference to the not-for-profit Golden Rice project.

  18. Genealogy of the "Green Revolution" gene in rice.

    Science.gov (United States)

    Nagano, Hironori; Onishi, Kazumitsu; Ogasawara, Mitsuhiro; Horiuchi, Yuki; Sano, Yoshio

    2005-10-01

    During the "Green Revolution" of rice, high-yielding varieties (HYVs) were developed using a semi-dwarf gene (sd1 or OsGA20ox2). The presence or absence of the two mutant alleles (DGWG type in Dee-geo-woo-gen and JKK type in Jikkoku) were surveyed by PCR using 256 accessions of eight wild and two cultivate rice species. The DGWG allele was detected in a landrace (Oryza sativa) and two accessions of wild rice (O. rufipogon), all of which are from China, showing their limited distribution. Genealogical studies of the OsGA20ox2 gene showed that the 62 sequences of O. sativa and O. rufipogon included 20 distinct haplotypes, indicating that the species complex contained OsGA20ox2 genes from two different lineages. The silent site nucleotide diversities (pi and theta(w)) were extremely low in Japonica rice, suggesting a genetic bottleneck. The haplotype network showed that the DGWG and JKK alleles were derived in different lineages. The DGWG carrier (W1944) had unique polymorphisms in the surrounding region of the locus, suggesting that the DGWG allele has been preserved in the wild progenitor, rather than that the DGWG allele has been introgressed from HYVs to W1944. Although a semi-dwarfing plant is a weak competitor under saturated fields, the crossing experiment revealed that the DGWG variant might have been preserved as a hidden variation in the genetic background of wild rice, without expressing a short-stature.

  19. Biodiversity Conservation in Rice Paddies in China: Toward Ecological Sustainability

    Directory of Open Access Journals (Sweden)

    Yufeng Luo

    2014-09-01

    Full Text Available Rice paddies are artificial wetlands that supply people with food and provide wildlife with habitats, breeding areas, shelters, feeding grounds and other services, and rice paddies play an important part in agricultural ecological systems. However, modern agricultural practices with large-scale intensive farming have significantly accelerated the homogenization of the paddy field ecosystem. Modern agriculture mostly relies on chemically-driven modern varieties and irrigation to ensure high production, resulting in the deterioration and imbalance of the ecosystem. Consequently, outbreaks of diseases, insects and weeds have become more frequent in paddy fields. This paper describes the current situation of rice paddy biodiversity in China and analyzes the community characteristics of arthropods and weedy plants. Meanwhile, we discuss how biodiversity was affected by modern agriculture changes, which have brought about a mounting crisis threatening to animals and plants once common in rice paddies. Measures should be focused to firstly preventing further deterioration and, then, also, promoting restoration processes. Ecological sustainability can be achieved by restoring paddy field biodiversity through protecting the ecological environment surrounding the paddy fields, improving paddy cropping patterns, growing rice with less agricultural chemicals and chemical fertilizers, constructing paddy systems with animals and plants and promoting ecological education and public awareness.

  20. Gene, protein and network of male sterility in rice

    Directory of Open Access Journals (Sweden)

    Wang eKun

    2013-04-01

    Full Text Available Rice is one of the most important model crop plants whose heterosis has been well exploited in commercial hybrid seed production via a variety of types of male sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility, photoperiod sensitive male sterility, self-incompatibility and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein and integrated network levels, and also, present a perspective on the engineering of male sterile lines for hybrid rice production.

  1. All roads lead to weediness: Patterns of genomic divergence reveal extensive recurrent weedy rice origins from South Asian Oryza.

    Science.gov (United States)

    Huang, Zhongyun; Young, Nelson D; Reagon, Michael; Hyma, Katie E; Olsen, Kenneth M; Jia, Yulin; Caicedo, Ana L

    2017-06-01

    Weedy rice (Oryza spp.), a weedy relative of cultivated rice (O. sativa), infests and persists in cultivated rice fields worldwide. Many weedy rice populations have evolved similar adaptive traits, considered part of the 'agricultural weed syndrome', making this an ideal model to study the genetic basis of parallel evolution. Understanding parallel evolution hinges on accurate knowledge of the genetic background and origins of existing weedy rice groups. Using population structure analyses of South Asian and US weedy rice, we show that weeds in South Asia have highly heterogeneous genetic backgrounds, with ancestry contributions both from cultivated varieties (aus and indica) and wild rice. Moreover, the two main groups of weedy rice in the USA, which are also related to aus and indica cultivars, constitute a separate origin from that of Asian weeds. Weedy rice populations in South Asia largely converge on presence of red pericarps and awns and on ease of shattering. Genomewide divergence scans between weed groups from the USA and South Asia, and their crop relatives are enriched for loci involved in metabolic processes. Some candidate genes related to iconic weedy traits and competitiveness are highly divergent between some weed-crop pairs, but are not shared among all weed-crop comparisons. Our results show that weedy rice is an extreme example of recurrent evolution, and suggest that most populations are evolving their weedy traits through different genetic mechanisms. © 2017 John Wiley & Sons Ltd.

  2. Downy mildew intensity in tolerant grapes varieties in highlands of southern Brazil

    Directory of Open Access Journals (Sweden)

    de Bem Betina

    2016-01-01

    Full Text Available The aim of this study was to evaluate the different degrees of tolerance to infection by P. viticolaamong three genotypes with constitutive resistance in comparison to susceptible varieties Vitis vinifera. For this purpose two experiments was conducted at EPAGRI Experimental Station, located in the city of São Joaquim, Santa Catarina State, at 2015/16 cycle. In the first experiment on the field, were quantified the incidence and severity and downy mildew intensity was compared by epidemiological variables, on the tolerant varieties Bronner, Regent, Cabernet Cortis and the susceptible Sangiovese. On the second experiment forty leaf discs for the same tolerant genotypes and the susceptible variety Chardonnay were artificially infected with P. viticola sporangia suspension and after seven days of incubation the discs were examined and the degree of infection was estimated based on the intensity of sporangiophore formation. Sangiovese showed highest downy mildew intensity in comparison to the tolerant varieties Cabernet Carbon, Regent and Bronner. Under controlled conditions, the susceptible variety Chardonnay showed higher sporangiophore formation on discs leafs in comparison to the tolerant varieties. All the downy mildew tolerant varieties evaluated showed lower disease development in comparison with V. vinifera varieties.

  3. Performance of elite grain sorghum varieties in the West Nile Agro ...

    African Journals Online (AJOL)

    ACSS

    colour and susceptibility to diseases like smuts as observed in the field. Results showed significant (P<0.05) difference in panicle weight and grain yield among varieties (Table 2 ), which results. T able 5. Effect of the different spacings on the agronomic and yield performance of the elite sorghum varieties. Inter-row Seedling ...

  4. The socio-economic impacts of rice policies implementation in rural Burma/Myanmar.

    Science.gov (United States)

    Thawnghmung, Ardeth Maung

    2003-01-01

    This paper, focusing on two rice-farming villages where the Burmese government has experimented with a variety of agricultural programmes, explores the problems associated with rice implementation processes. In particular it looks at the basic structure and operation of agricultural administration — salary and income of government officials, the predominance of military officers in civilian ministries and departments, the creation of departments with overlapping responsibilities, and the hierarchical structure of the Agricultural Ministry — and highlight their limitations. It provides another aspect to evaluating the roots of poverty among average rice farmers.

  5. Induction of apomixis and fixation of heterosis in Egyptian rice Hybrid1 line using colchicine mutagenesis

    OpenAIRE

    Reda M. Gaafar; Adel R. El Shanshoury; Ahmad A. El Hisseiwy; Mahmoud A. AbdAlhak; Aimn F. Omar; Mohammad M. Abd El Wahab; Randa S. Nofal

    2017-01-01

    It is known that hybrid rice yields 15–20% over inbred varieties in first generation because of heterosis. However, heterosis is normally broken due to segregation. Applying apomixis produces plants as a clone of mother plant and overcomes the problem of breaking heterosis. In order to fix heterosis in the Egyptian rice Hybrid1, their seeds were mutagenized in 0.2% colchicine for two time periods 24 and 50 h. After colchicine mutagenesis, rice seedlings were grown in the field till maturation...

  6. Molecular progress on the mapping and cloning of functional genes for blast disease in rice (Oryza sativa L.): current status and future considerations.

    Science.gov (United States)

    Ashkani, S; Rafii, M Y; Shabanimofrad, M; Ghasemzadeh, A; Ravanfar, S A; Latif, M A

    2016-01-01

    Rice blast disease, which is caused by the fungal pathogen Magnaporthe oryzae, is a recurring problem in all rice-growing regions of the world. The use of resistance (R) genes in rice improvement breeding programmes has been considered to be one of the best options for crop protection and blast management. Alternatively, quantitative resistance conferred by quantitative trait loci (QTLs) is also a valuable resource for the improvement of rice disease resistance. In the past, intensive efforts have been made to identify major R-genes as well as QTLs for blast disease using molecular techniques. A review of bibliographic references shows over 100 blast resistance genes and a larger number of QTLs (∼500) that were mapped to the rice genome. Of the blast resistance genes, identified in different genotypes of rice, ∼22 have been cloned and characterized at the molecular level. In this review, we have summarized the reported rice blast resistance genes and QTLs for utilization in future molecular breeding programmes to introgress high-degree resistance or to pyramid R-genes in commercial cultivars that are susceptible to M. oryzae. The goal of this review is to provide an overview of the significant studies in order to update our understanding of the molecular progress on rice and M. oryzae. This information will assist rice breeders to improve the resistance to rice blast using marker-assisted selection which continues to be a priority for rice-breeding programmes.

  7. Remote sensing based change analysis of rice environments in Odisha, India.

    Science.gov (United States)

    Gumma, Murali Krishna; Mohanty, Samarendu; Nelson, Andrew; Arnel, Rala; Mohammed, Irshad A; Das, Satya Ranjan

    2015-01-15

    The rainfed rice-growing environment is perhaps one of the most vulnerable to water stress such as drought and floods. It is important to determine the spatial extent of the stress-prone areas to effectively and efficiently promote proper technologies (e.g., stress-tolerant varieties) to tackle the problem of sustainable food production. This study was conducted in Odisha state located in eastern India. Odisha is predominantly a rainfed rice ecosystem (71% rainfed and 29% canal irrigated during kharif-monsoon season), where rice is the major crop and staple food of the people. However, rice productivity in Odisha is one of the lowest in India and a significant decline (9%) in rice cultivated area was observed in 2002 (a drought year). The present study analyzed the temporal rice cropping pattern in various ecosystems and identified the stress-prone areas due to submergence (flooding) and water shortage. The spatial distribution of rice areas was mapped using MODIS (MOD09Q1) 250-m 8-day time-series data (2000-2010) and spectral matching techniques. The mapped rice areas were strongly correlated (R(2) = 90%) with district-level statistics. Also the class accuracy based on field-plot data was 84.8%. The area under the rainfed rice ecosystem continues to dominate, recording the largest share among rice classes across all the years. The use of remote-sensing techniques is rapid, cost-effective, and reliable to monitor changes in rice cultivated area over long periods of time and estimate the reduction in area cultivated due to abiotic stress such as water stress and submergence. Agricultural research institutes and line departments in the government can use these techniques for better planning, regular monitoring of land-use changes, and dissemination of appropriate technologies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Dematerialization: Variety, caution, and persistence.

    Science.gov (United States)

    Ausubel, Jesse H; Waggoner, Paul E

    2008-09-02

    Dematerialization, represented by declining consumption per GDP of energy or of goods, offers some hope for rising environmental quality with development. The declining proportion of income spent on staples as affluence grows, which income elasticity <1.0 measures, makes dematerialization widespread. Further, as learning improves efficiency of resource use, the intensity of environmental impact per production of staples often declines. We observe that combinations of low income elasticity for staples and of learning by producers cause a variety of dematerializations and declining intensities of impact, from energy use and carbon emission to food consumption and fertilizer use, globally and in countries ranging from the United States and France to China, India, Brazil, and Indonesia. Because dematerialization and intensity of impact are ratios of parameters that may be variously defined and are sometimes difficult to estimate, their fluctuations must be interpreted cautiously. Nevertheless, substantial declining intensity of impact, and especially, dematerialization persisted between 1980 and 2006.

  9. Silicon alleviates drought stress of rice plants by improving plant water status, photosynthesis and mineral nutrient absorption.

    Science.gov (United States)

    Chen, Wei; Yao, Xiaoqin; Cai, Kunzheng; Chen, Jining

    2011-07-01

    Drought is a major constraint for rice production in the rainfed lowlands in China. Silicon (Si) has been verified to play an important role in enhancing plant resistance to environmental stress. Two near-isogenic lines of rice (Oryza sativa L.), w-14 (drought susceptible) and w-20 (drought resistant), were selected to study the effects of exogenous Si application on the physiological traits and nutritional status of rice under drought stress. In wet conditions, Si supply had no effects on growth and physiological parameters of rice plants. Drought stress was found to reduce dry weight, root traits, water potential, photosynthetic parameters, basal quantum yield (F(v)/F(0)), and maximum quantum efficiency of PSII photochemistry (F(v)/F(m)) in rice plants, while Si application significantly increased photosynthetic rate (Pr), transpiration rate (Tr), F(v)/F(0), and F(v)/F(m) of rice plants under drought stress. In addition, water stress increased K, Na, Ca, Mg, Fe content of rice plants, but Si treatment significantly reduced these nutrient level. These results suggested that silicon application was useful to increase drought resistance of rice through the enhancement of photochemical efficiency and adjustment of the mineral nutrient absorption in rice plants.

  10. Understanding the Spatially Variable Effects of Climate Change on Rice Yield for Three Ecotypes in Bangladesh, 1981–2010

    Directory of Open Access Journals (Sweden)

    Iffat Ara

    2017-01-01

    Full Text Available Climate change will impact on rice food security in many parts of the world, including Bangladesh. Little attention has been given to understanding the impact of climate on rice yield for three main ecotypes (Aus, Aman, and Boro in different areas of the country. The aim of this paper was to analyse the spatiotemporal dynamics of rice yield and climatic variables and the spatially variable climate effects on rice yield for these ecotypes in Bangladesh during 1981–2010 by employing linear mixed models and generalized linear models. The results demonstrated the substantial spatiotemporal variations of rice yield for all ecotypes across the country. Rice yield for ecotypes was more susceptible to temperature changes than rainfall effects. Modelling of a 1°C temperature increase in the country showed strong regional differences in rice yield for these ecotypes. The study concludes that future temperature changes are likely to change regional rice yield for all ecotypes and hence impact food security. The results have important consequences for food security by indicating the need for appropriate region-specific adaptation measures to reduce rice yield variability in the future. The results show the need to consider spatial differences for policy development to improve food security in Bangladesh.

  11. Effect of Heating Processes and Home Cooking Methods of Rice on Concentration of Aflatoxin B1

    Directory of Open Access Journals (Sweden)

    B Hajimohammadi

    2016-09-01

    Full Text Available Introduction: Mycotoxin contamination of crops for human and animal health has been facing a serious concern. Aflatoxin B1 is the most toxic types of aflatoxins in foodssuch as rice. The aim of this study was to investigate the Effect of heating processes and home cooking methods of rice on concentration of aflatoxin B1. methods: The heating processes of 20 and 120 minutes and rinse in three types of roasted rice, boiled and water cooked was studied in naturally contaminated with aflatoxin  B1 and the amount by high performance liquid chromatography (HPLC measured. Results: In the cases of 20 minutes and 120 minutes, the mean concentration of aflatoxin  B1 heats rice decreased as much as 16.6% and 81.7%. Although this reduction was not statistically significant heating at 20 minutes but at 120 minutes with heating was significant(P<0/05. The decrease in the average concentration of aflatoxin  B1in boiled, water cooked and roasted rice to order 60.2%, 85.5% and 87.6% indicated that this reduction was not statistically significant in the boiled cooking, but the cooking utensils and this reduction was not statistically with fried rice (P<0/05 was significant. Conclusion: The results show that the processes of heat and cook the rice variety could reduce the risks of aflatoxin  B1 in rice consumed by man.

  12. Seed-vectored endophytic bacteria modulate development of rice seedlings.

    Science.gov (United States)

    Verma, S K; Kingsley, K; Irizarry, I; Bergen, M; Kharwar, R N; White, J F

    2017-06-01

    The aim of the present study was to evaluate the effects of the removal of indigenous bacteria from rice seeds on seedling growth and development. Here we report the presence of three indigenous endophytic bacteria in rice seeds that play important roles in modulating seedling development (shoot and root lengths, and formation of root hairs and secondary roots) and defence against pathogens. Seed-associated bacteria were removed using surface sterilization with NaOCl (bleach) followed by antibiotic treatment. When bacteria were absent, growth of seedlings in terms of root hair development and overall seedling size was less than that of seedlings that contained bacteria. Reactive oxygen staining of seedlings showed that endophytic bacteria became intracellular in root parenchyma cells and root hairs. Roots containing endophytic bacteria were seen to stain densely for reactive oxygen, while roots free of bacteria stained lightly for reactive oxygen. Bacteria were isolated and identified as Enterobacter asburiae (VWB1), Pantoea dispersa (VWB2) and Pseudomonas putida (VWB3) by 16S rDNA sequencing. Bacteria were found to produce indole acetic acid (auxins), inhibited the pathogen Fusarium oxysporum and solubilized phosphate. Reinoculation of bacteria onto seedlings derived from surface-disinfected rice and Bermuda grass seeds significantly restored seedling growth and development. Rice seeds harbour indigenous bacterial endophytes that greatly influence seedling growth and development, including root and shoot lengths, root hair formation and disease susceptibility of rice seedlings. This study shows that seeds of rice naturally harbour bacterial endophytes that play key roles in modulation of seedling development. © 2017 The Society for Applied Microbiology.

  13. Soil amendments and cultivar selection can improve rice yield in salt-influenced (tsunami-affected) paddy fields in Sri Lanka.

    Science.gov (United States)

    Reichenauer, Thomas G; Panamulla, Sunil; Subasinghe, Siripala; Wimmer, Bernhard

    2009-10-01

    The tsunami disaster in the Indian Ocean in December 2004 caused devastation of agricultural soils by salt water over wide areas. Many rice fields located close to the coast were affected by the flood of seawater. Electric conductivity (EC) of soils in tsunami-affected rice fields was found to be higher compared to unaffected fields 2 years after the tsunami. Four soil amendments (gypsum, dolomite, cinnamon ash and rice-husk-charcoal) were tested for their influence on improving the yield parameters of rice grown in a tsunami-affected and a non-affected area. Yield parameters were compared with an untreated control of the same cultivar (AT362) and with a salt resistant rice variety (AT354). The salt resistant variety had the highest grain yield. The two amendments gypsum and rice-husk-charcoal led to an increase in grain yield compared to the untreated control, whereas dolomite and cinnamon ash had no significant effect on grain yield.

  14. Overexpression of the rice carotenoid cleavage dioxygenase 1 gene in Golden Rice endosperm suggests apocarotenoids as substrates in planta.

    Science.gov (United States)

    Ilg, Andrea; Yu, Qiuju; Schaub, Patrick; Beyer, Peter; Al-Babili, Salim

    2010-08-01

    Carotenoids are converted by carotenoid cleavage dioxygenases that catalyze oxidative cleavage reactions leading to apocarotenoids. However, apocarotenoids can also be further truncated by some members of this enzyme family. The plant carotenoid cleavage dioxygenase 1 (CCD1) subfamily is known to degrade both carotenoids and apocarotenoids in vitro, leading to different volatile compounds. In this study, we investigated the impact of the rice CCD1 (OsCCD1) on the pigmentation of Golden Rice 2 (GR2), a genetically modified rice variety accumulating carotenoids in the endosperm. For this purpose, the corresponding cDNA was introduced into the rice genome under the control of an endosperm-specific promoter in sense and anti-sense orientations. Despite high expression levels of OsCCD1 in sense plants, pigment analysis revealed carotenoid levels and patterns comparable to those of GR2, pleading against carotenoids as substrates in rice endosperm. In support, similar carotenoid contents were determined in anti-sense plants. To check whether OsCCD1 overexpressed in GR2 endosperm is active, in vitro assays were performed with apocarotenoid substrates. HPLC analysis confirmed the cleavage activity of introduced OsCCD1. Our data indicate that apocarotenoids rather than carotenoids are the substrates of OsCCD1 in planta.

  15. Prevalence of Rice Yellow Mottle Virus (RYMV) on Rice Plants ...

    African Journals Online (AJOL)

    Z. variegatus 1. 0.688. 1.037. Locust. L. migratoides. 1. 1.023. 1.037. Discussion. Viral disease due to RYMV had been a major challenge in rice production in Nigeria since 1976 when it was reported by Rossel et al. (1982). Areas of rice production in Nigeria where the virus had been detected included. Badeggi, Ibadan ...

  16. The Haitian Rice Tariff

    Directory of Open Access Journals (Sweden)

    Mats Lundahl

    2016-04-01

    Full Text Available Se ha argumentado que los problemas agríco-las de Haití derivan de la tarifa del arroz de a mediados de los años noventa. Antes, supues-tamente, Haití fue autosuficiente, abastecida por su producción doméstica. Después de la reducción, el mercado haitiano se inundó en importaciones de arroz barato de los EEUU, lo cual despojó a los campesinos de sus fincas, convirtiendolos en migrantes internos, hacia los empleos de bajo pago de las ciudades. El artículo rechaza ese argumento y demuestra que es falso. La malnutrición fue un fenómeno extendido en Haití mucho antes de la reducción de la tarifa del arroz, la cual tampoco tuvo un gran impacto en la importación y la producción doméstica del arroz. Lo que sí impulsó el aumento de las importaciones fue el crecimiento de la población. También el artículo argumenta que un aumento de la tarifa del arroz no solucionará el problema de la alimentación que sufre Haití. English: It has been argued that Haiti’s agricultural problems derive from the reduction of the rice tariff in the mid-1990s. Before that Haiti was allegedly able to meet its food needs by domestic production. After the reduction the Haitian market was swamped by imports of cheap American rice which drove the farmers off their lands and forced them to migrate to low-wage industrial jobs in the cities. The article demonstrates that the argument is false. Malnutrition was widespread in Haiti long before the rice tariff reduction, and the latter did not have much of an impact on rice imports and domestic production. Instead, the main driving force behind imports appears to be population growth. It is also shown that an increase of the rice tariff will not solve Haiti’s food problem.

  17. The effect of nitrogen application on the development of rusts on wheat varieties

    Directory of Open Access Journals (Sweden)

    M. E. Haggag

    2014-11-01

    Full Text Available The effect of four different levels of nitrogen fertilization on the severity of rusts on three local Egyptian wheat varieties have been investigated. Nitrogen fertilizer was at the rates 0, 40, 60, and 80 kg nitrogen per feddan. Data obtained indicated that resistance of the varieties did not change while percent severity of postules on susceptible, moderately susceptible and moderately resistant varieties was increased as the level of nitrogen fertilization increased. Heavy doses of nitrogen promoted the size and frequency of postules and hence the rust growth and predisposed the plants to higher infection with rusts.

  18. Field Trials Reveal Ecotype-Specific Responses to Mycorrhizal Inoculation in Rice.

    Directory of Open Access Journals (Sweden)

    Abdala Gamby Diedhiou

    Full Text Available The overuse of agricultural chemicals such as fertilizer and pesticides aimed at increasing crop yield results in environmental damage, particularly in the Sahelian zone where soils are fragile. Crop inoculation with beneficial soil microbes appears as a good alternative for reducing agricultural chemical needs, especially for small farmers. This, however, requires selecting optimal combinations of crop varieties and beneficial microbes tested in field conditions. In this study, we investigated the response of rice plants to inoculation with arbuscular mycorrhizal fungi (AMF and plant growth promoting bacteria (PGPB under screenhouse and field conditions in two consecutive seasons in Senegal. Evaluation of single and mixed inoculations with AMF and PGPB was conducted on rice (Oryza sativa variety Sahel 202, on sterile soil under screenhouse conditions. We observed that inoculated plants, especially plants treated with AMF, grew taller, matured earlier and had higher grain yield than the non-inoculated plants. Mixed inoculation trials with two AMF strains were then conducted under irrigated field conditions with four O. sativa varieties, two O. glaberrima varieties and two interspecific NERICA varieties, belonging to 3 ecotypes (upland, irrigated, and rainfed lowland. We observed that the upland varieties had the best responses to inoculation, especially with regards to grain yield, harvest index and spikelet fertility. These results show the potential of using AMF to improve rice production with less chemical fertilizers and present new opportunities for the genetic improvement in rice to transfer the ability of forming beneficial rice-microbe associations into high yielding varieties in order to increase further rice yield potentials.

  19. Crop and varietal diversification of rainfed rice based cropping systems for higher productivity and profitability in Eastern India.

    Science.gov (United States)

    Lal, B; Gautam, Priyanka; Panda, B B; Raja, R; Singh, Teekam; Tripathi, R; Shahid, M; Nayak, A K

    2017-01-01

    Rice-rice system and rice fallows are no longer productive in Southeast Asia. Crop and varietal diversification of the rice based cropping systems may improve the productivity and profitability of the systems. Diversification is also a viable option to mitigate the risk of climate change. In Eastern India, farmers cultivate rice during rainy season (June-September) and land leftovers fallow after rice harvest in the post-rainy season (November-May) due to lack of sufficient rainfall or irrigation amenities. However, in lowland areas, sufficient residual soil moistures are available in rice fallow in the post-rainy season (November-March), which can be utilized for raising second crops in the region. Implementation of suitable crop/varietal diversification is thus very much vital to achieve this objective. To assess the yield performance of rice varieties under timely and late sown conditions and to evaluate the performance of dry season crops following them, three different duration rice cultivars were transplanted in July and August. In dry season several non-rice crops were sown in rice fallow to constitute a cropping system. The results revealed that tiller occurrence, biomass accumulation, dry matter remobilization, crop growth rate, and ultimately yield were significantly decreased under late transplanting. On an average, around 30% yield reduction obtained under late sowing may be due to low temperature stress and high rainfall at reproductive stages of the crop. Dry season crops following short duration rice cultivars performed better in terms of grain yield. In the dry season, toria was profitable when sown earlier and if sowing was delayed greengram was suitable. Highest system productivity and profitability under timely sown rice may be due to higher dry matter remobilization from source to sink. A significant correlation was observed between biomass production and grain yield. We infer that late transplanting decrease the tiller occurrence and assimilate

  20. High day- and night-time temperatures affect grain growth dynamics in contrasting rice genotypes

    NARCIS (Netherlands)

    Shi, Wanju; Yin, Xinyou; Struik, Paul C.; Solis, Celymar; Xie, Fangming; Schmidt, Ralf C.; Huang, Min; Zou, Yingbin; Ye, Changrong; Jagadish, S.V.K.

    2017-01-01

    Rice grain yield and quality are predicted to be highly vulnerable to global warming. Five genotypes including heat-tolerant and susceptible checks, a heat-tolerant near-isogenic line and two hybrids were exposed to control (31 °C/23 °C, day/night), high night-time temperature (HNT; 31 °C/30 °C),

  1. Impact of volunteer rice infestation on yield and grain quality of rice.

    Science.gov (United States)

    Singh, Vijay; Burgos, Nilda R; Singh, Shilpa; Gealy, David R; Gbur, Edward E; Caicedo, Ana L

    2017-03-01

    Volunteer rice (Oryza sativa L.) grains may differ in physicochemical traits from cultivated rice, which may reduce the quality of harvested rice grain. To evaluate the effect of volunteer rice on cultivated rice, fields were surveyed in Arkansas in 2012. Cropping history that included hybrid cultivars in the previous two years (2010 and 2011) had higher volunteer rice infestation (20%) compared with fields planted previously with inbred rice (5.5%). The total grain yield of rice was reduced by 0.4% for every 1% increase in volunteer rice density. The grain quality did not change in fields planted with the same cultivar for three years. Volunteer rice density of at least 7.6% negatively impacted the head rice and when infestation reached 17.7%, it also reduced the rice grain yield. The protein and amylose contents of rice were not affected until volunteer rice infestation exceeded 30%. Crop rotation systems that include hybrid rice are expected to have higher volunteer rice infestation than systems without hybrid rice. It is predicted that, at 8% infestation, volunteer rice will start to impact head rice yield and will reduce total yield at 18% infestation. It could alter the chemical quality of rice grain at >30% infestation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  2. Red yeast rice for dysipidemia.

    Science.gov (United States)

    Shamim, Shariq; Al Badarin, Firas J; DiNicolantonio, James J; Lavie, Carl J; O'Keefe, James H

    2013-01-01

    Red yeast rice is an ancient Chinese food product that contains monacolins, chemical substances that are similar to statins in their mechanisms of action and lipid lowering properties. Several studies have found red yeast rice to be moderately effective at improving the lipid profile, particularly for lowering the low-density lipoprotein cholesterol levels. One large randomized controlled study from China found that red yeast rice significantly improved risk of major adverse cardiovascular events and overall survival in patients following myocardial infarction. Thus, red yeast rice is a potentially useful over-the-counter cholesterol-lowering agent. However, many red yeast rice formulations are non-standardized and unregulated food supplements, and there is a need for further research and regulation of production.

  3. TPS46, a Rice Terpene Synthase Conferring Natural Resistance to Bird Cherry-Oat Aphid, Rhopalosiphum padi (Linnaeus).

    Science.gov (United States)

    Sun, Yang; Huang, Xinzheng; Ning, Yuese; Jing, Weixia; Bruce, Toby J A; Qi, Fangjun; Xu, Qixia; Wu, Kongming; Zhang, Yongjun; Guo, Yuyuan

    2017-01-01

    Plant terpene synthases (TPSs) are key enzymes responsible for terpene biosynthesis, and can play important roles in defense against herbivore attack. In rice, the protein sequence of TPS46 was most closely related to maize TPS10. However, unlike maize tps10, tps46 was also constitutively expressed in rice even in the absence of herbivore attack. Potential roles or constitutive emissions of specific volatiles may due to the constitutive expressions of tps46 in rice. Therefore, in the present study, RNA interference (Ri) and overexpression (Oe) rice lines were generated to investigate the potential function of TPS46 in Oryza sativa sp. japonica. Interestingly, the rice plants become more susceptible to Rhopalosiphum padi when expression of tps46 was silenced compared with Wt in greenhouse conditions. Artificial infestation bioassays further confirmed that Ri rice lines were susceptible to R. padi, whereas Oe rice lines were repellent to R. padi. Based on GC-MS and ToF-MS analysis, a total of eight volatile products catalyzed by TPS46 in rice were identified. Among them, only limonene and Eβf could be detected in all the Ri, Oe, and Wt lines, whereas other six volatiles were only found in the blend of volatiles from Oe lines. Moreover, the amount of constitutive limonene and Eβf in the Ri lines was significantly lower than in Wt lines, while the amounts of these two volatiles in the Oe line were obviously higher than in control rice. Our data suggested that the constitutive emissions of Eβf and limonene regulated by the constitutive expression of tps46 may play a crucial role in rice defense against R. padi. Consequently, tps46 could be a potential target gene to be employed for improving the resistance of plants to aphids.

  4. Non-nutritive mineral effects on rice

    Science.gov (United States)

    The study of the responses of rice to non-nutritive minerals has numerous benefits. Rice is the current model plant for genomic studies of crops and with the sequencing of the rice genome, information obtained from rice can be extended to other organisms, which has been particularly valuable regard...

  5. Relative susceptibility of banana cultivars to Xanthomonas ...

    African Journals Online (AJOL)

    short time making the disease one of the most dreaded in banana. The disease affects almost all varieties of commonly grown banana cultivars. Some knowledge of the relative susceptibility of banana cultivars would be extremely useful and could be a basis for management strategies for BXW. Ten banana cultivars were ...

  6. Management of Striga Hermonthica (Del.) Benth in Upland Rice ...

    African Journals Online (AJOL)

    The effects of different rates of Nitrogen (0, 30, 60, 90 and 120 kg N/ha) on the reaction of five (FARO 46, FARO 11, FARO 45, FARO 48 and FARO 38) and seven (FARO 46, FARO 11, FARO 45, FARO 48, FARO 38, FARO 40 and WAB 56-50) varieties of upland rice were studied in field trials conducted in both the dry and ...

  7. Bridging the Rice Yield Gaps under Drought: QTLs, Genes, and their Use in Breeding Programs

    Directory of Open Access Journals (Sweden)

    Nitika Sandhu

    2017-04-01

    Full Text Available Rice is the staple food for more than half of the world’s population. Although rice production has doubled in the last 30 years as a result of the development of high-yield, widely adaptable, resource-responsive, semi-dwarf varieties, the threat of a food crisis remains as severe as it was 60 years ago due to the ever-increasing population, water scarcity, labor scarcity, shifting climatic conditions, pest/diseases, loss of productive land to housing, industries, rising sea levels, increasing incidences of drought, flood, urbanization, soil erosion, reduction in soil nutrient status, and environmental issues associated with high-input agriculture. Among these, drought is predicted to be the most severe stress that reduces rice yield. Systematic research on drought over the last 10 years has been conducted across institutes on physiology, breeding, molecular genetics, biotechnology, and cellular and molecular biology. This has provided a better understanding of plant drought mechanisms and has helped scientists to devise better strategies to reduce rice yield losses under drought stress. These include the identification of quantitative trait loci (QTLs for grain yield under drought as well as many agronomically important traits related to drought tolerance, marker-assisted pyramiding of genetic regions that increase yield under drought, development of efficient techniques for genetic transformation, complete sequencing and annotation of rice genomes, and synteny studies of rice and other cereal genomes. Conventional and marker-assisted breeding rice lines containing useful introgressed genes or loci have been field tested and released as varieties. Still, there is a long way to go towards developing drought-tolerant rice varieties by exploiting existing genetic diversity, identifying superior alleles for drought tolerance, understanding interactions among alleles for drought tolerance and their interaction with genetic backgrounds, and

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

    Directory of Open Access Journals (Sweden)

    Longmei Wu

    2017-05-01

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

  9. Rice-arsenate interactions in hydroponics: whole genome transcriptional analysis.

    Science.gov (United States)

    Norton, Gareth J; Lou-Hing, Daniel E; Meharg, Andrew A; Price, Adam H

    2008-01-01

    Rice (Oryza sativa) varieties that are arsenate-tolerant (Bala) and -sensitive (Azucena) were used to conduct a transcriptome analysis of the response of rice seedlings to sodium arsenate (AsV) in hydroponic solution. RNA extracted from the roots of three replicate experiments of plants grown for 1 week in phosphate-free nutrient with or without 13.3 muM AsV was used to challenge the Affymetrix (52K) GeneChip Rice Genome array. A total of 576 probe sets were significantly up-regulated at least 2-fold in both varieties, whereas 622 were down-regulated. Ontological classification is presented. As expected, a large number of transcription factors, stress proteins, and transporters demonstrated differential expression. Striking is the lack of response of classic oxidative stress-responsive genes or phytochelatin synthases/synthatases. However, the large number of responses from genes involved in glutathione synthesis, metabolism, and transport suggests that glutathione conjugation and arsenate methylation may be important biochemical responses to arsenate challenge. In this report, no attempt is made to dissect differences in the response of the tolerant and sensitive variety, but analysis in a companion article will link gene expression to the known tolerance loci available in the BalaxAzucena mapping population.

  10. Molecular and Biochemical Analysis of Two Rice Flavonoid 3’-Hydroxylase to Evaluate Their Roles in Flavonoid Biosynthesis in Rice Grain

    Directory of Open Access Journals (Sweden)

    Sangkyu Park

    2016-09-01

    Full Text Available Anthocyanins and proanthocyanidins, the major flavonoids in black and red rice grains, respectively, are mainly derived from 3′,4′-dihydroxylated leucocyanidin. 3′-Hydroxylation of flavonoids in rice is catalyzed by flavonoid 3′-hydroxylase (F3′H: EC 1.14.13.21. We isolated cDNA clones of the two rice F3′H genes (CYP75B3 and CYP75B4 from Korean varieties of white, black, and red rice. Sequence analysis revealed allelic variants of each gene containing one or two amino acid substitutions. Heterologous expression in yeast demonstrated that CYP75B3 preferred kaempferol to other substrates, and had a low preference for dihydrokaempferol. CYP75B4 exhibited a higher preference for apigenin than for other substrates. CYP75B3 from black rice showed an approximately two-fold increase in catalytic efficiencies for naringenin and dihydrokaempferol compared to CYP75B3s from white and red rice. The F3′H activity of CYP75B3 was much higher than that of CYP75B4. Gene expression analysis showed that CYP75B3, CYP75B4, and most other flavonoid pathway genes were predominantly expressed in the developing seeds of black rice, but not in those of white and red rice, which is consistent with the pigmentation patterns of the seeds. The expression levels of CYP75B4 were relatively higher than those of CYP75B3 in the developing seeds, leaves, and roots of white rice.

  11. Growth-inhibitory effects of pigmented rice bran extracts and three red bran fractions against human cancer cells: Relationships to composition and antioxidative activities

    Science.gov (United States)

    We determined the phenolic, anthocyanin, and proanthocyanidin content of three brown, purple, and red rice brans isolated from different rice varieties using HPLC-PDA with the aid of 27 standards of known structure and by matching unknown peaks to a spectral library of known compounds. DPPH and ORA...

  12. Evaluation of stability of arsenic species in rice

    Energy Technology Data Exchange (ETDEWEB)

    Pizarro, Isabel; Gomez, Milagros; Palacios, Maria Antonia; Camara, Carmen [Analytical Chemistry Department, Chemistry Faculty, Complutense University, Avda Complutense s/n, 28040, Madrid (Spain)

    2003-05-01

    Although most edible vegetables do not accumulate As at a high rate, rice, carrots and certain others are exceptions. In addition to nutritional or toxicological considerations, the relatively high level and variety of As species present in rice make it a very suitable matrix for a candidate reference material representative of terrestrial biological samples.An analytical procedure was developed for As speciation in rice based on the use of a 1:1 methanol-water mixture for species extraction, an anion Hamilton PRPX-100 column (at pH 6, and phosphate mobile phase 10 mM), and a cation Hamilton PRP-X200 column (at pH 2.8 in pyridine formiate 4 mM) for species separation and final determination by HPLC-ICP-MS.The detection limits for dry flour rice expressed as As were 2 and 3 ng g{sup -1} for As(III) and AsB on the cation column and 3, 6 and 5 ng g{sup -1} for As(V), MMA and DMA, respectively, on the anion column.The methodology developed was applied to check the stability of As species in the water-methanol extract and also under different processing steps and storage time and temperature conditions.It was demonstrated that the As species in the water-methanol extracts stored at +4 C remained stable for at least one month. Once the rice grains are ground, the MMA and As(V) species are not stable under any storage conditions probably due to microbiological activity. When ground rice is {gamma}-irradiated species remain stable although the AsB does not appear. (orig.)

  13. The rice genome project in Japan

    OpenAIRE

    Sasaki, Takuji

    1998-01-01

    Since 1991, the Rice Genome Research Program in Japan has carried out rice genomics, such as large-scale cDNA analysis, construction of a fine-scale restriction fragment length polymorphism map, and physical mapping of the rice genome with yeast artificial chromosome clones. These studies have made a great impact on research into grass genomes and made rice a model plant for other cereal crop research. Starting in 1998, the Rice Genome Research Program will step in...

  14. Productivity, Profitability and Resource Use Efficiency: A Comparative Analysis between Conventional and High Yielding Rice in Rajbari District, Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Yahia Bapari

    2016-10-01

    Full Text Available The study was analyzed the determinants, costs and benefits and resources allocation of both conventional and high yielding rice cultivation over the Rajbari district of Bangladesh. Data were accumulated from 300 regular rice growers of conventional and high yielding varieties and random sampling technique was applied for selecting the respondents from the study area from which information was collected through pre-tested questionnaire. Cobb – Douglas production function and gross margin were mainly used to determine the productivities and profits of both rice and the marginal value of the product was highly recommended to derive the optimal use of the resources. Results obtained by applying ordinary least square method showed that the most important factors of production in the study area were irrigation, labor, fertilizer and insecticide costs whose elasticities were 0.904, 0.048, 0.045 and 0.044 respectively and insignificant factors were seed and ploughing costs whose elasticities were – 0.009 and 0.030 respectively for high yielding rice. On the other hand, irrigation, insecticide, seed and ploughing costs of elasticities 0.880, 0.589, 0.116 and – 0.127 respectively were the important factors and minor role playing factors were labor and fertilizer costs whose elasticities were 0.098 and 0.077 respectively for conventional yielding rice. The core message from productivity analysis was that the irrigation was key variable which played a positive and vital role in producing rice of both varieties. All variables (resources were economically misallocated in the production activities of both varieties along the study area but high yielding rice was more profitable than conventional one. Results also showed that the farmers of the study area produced rice of both varieties in the inefficient range of production. Continuous supply of electricity, flexible credit and improving the existing resources were the prime policy recommendations of

  15. The Effect of Potato Varieties on Population of Golden Cyst Nematode (Globodera rostochiensis

    Directory of Open Access Journals (Sweden)

    Jasmina Bačić

    2010-01-01

    Full Text Available The effect of susceptibility/resistance of seed potato varieties on population of golden cyst nematode – Globodera rostochiensis (Wollenweber, 1923 Skarbilovich, 1959 was investigated in the infested field of Brdo, KO Ljubovija No. 413, in Mačva District in Serbia during 2002 and 2003. The susceptible varieties Desiree, Innovator, Kennebec, Cleopatra, and Kondor were used in the experiment as varieties frequently grown in this district. The resistant ex-andigena varieties Agria, Frisia, Latona, Saturna, and Tresor were chosen on the basis of identified pathotypes of G. rostochiensis population originating from the aforementioned infested field. The results of this research indicated that nematode population of G. rostochiensis could be reduced and higher yield obtained by growing the resistant ex-andigena varieties in case of presence of pathotype Ro1. In the second year of investigation, final cyst density was 3.5 times lower than in the first year. It subsequently affected the crop yield which increased in the second year. The lowest crop yield was observed for susceptible varieties Kennebec (8.5 t/ha and Cleopatra (16.9 t/ha, and the highest for resistant varieties Agria (25.7 t/ha and Frisia (29.1 t/ha. These results may be useful to growers in the infested areas of Mačva District when choosing potato varieties, in order to eradicate the quarantine nematode G. rostochiensis.

  16. Effect of microwave and air drying of parboiled rice on stabilization of rice bran oil

    Directory of Open Access Journals (Sweden)

    Rizk, Laila F.

    1995-06-01

    Full Text Available Two rice varieties, Giza 175 (short grain and Giza 181 (long grain were partDoiled by soaking the grains at room temperature for 20 hours and steaming for 15 min then dried either at room temperature or by microwave. The results indicated that air and microwave drying significantly increased oil extraction in both rice bran varieties. Parboiling followed by air or microwave drying produced a slight change on protein, fiber and ash content of rice bran and reduced the development of free fatty acids (F.F.A. In oil bran. Microwave samples have less F.F.A. content than the corresponding samples air dried. Oils from the cold stored rice bran presented lower F.F.A. than the corresponding oil bran stored at room temperature. The ratio between total unsaturated fatty acids and total saturated ones (Tu/Ts decreased after air and microwave drying. Results also show that air drying increased the ratio of total hydrocarbons and total sterols (Tu/Ts in both varieties while microwave decreased it.

    Dos variedades de arroz, Giza 175 (grano corto y Giza 181 (grano largo se precocieron mediante la puesta en remojo de los granos a temperatura ambiente durante 20 horas y cocimiento al vapor durante 15 minutos, luego se secaron a temperatura ambiente o por microondas. Los resultados indicaron que el secado al aire y en microondas aumentó significativamente la extracción del aceite en ambas variedades de salvado de arroz. El precocido seguido del secado al aire o en microondas produjo un cambio pequeño en el contenido en proteína, fibra y ceniza y redujo el desarrollo de ácidos grasos libres (F.F.A. en el aceite de salvado. Las muestras secadas en microondas tuvieron un menor contenido en F.F.A. que las muestras correspondientes al secado en aire. Aceites de salvado de arroz almacenado en frió presentaron menor F.F.A. que los almacenados a temperatura ambiente. La relación entre ácidos grasos insaturados totales y los saturados totales (Tu/Ts disminuy

  17. Introducing non-flooded crops in rice-dominated landscapes: Impact on carbon, nitrogen and water budgets

    Science.gov (United States)

    Jauker, Frank; Wassmann, Reiner; Amelung, Wulf; Breuer, Lutz; Butterbach-Bahl, Klaus; Conrad, Ralf; Ekschmitt, Klemens; Goldbach, Heiner; He, Yao; John, Katharina; Kiese, Ralf; Kraus, David; Reinhold-Hurek, Barbara; Siemens, Jan; Weller, Sebastian; Wolters, Volkmar

    2013-04-01

    Rice production consumes about 30% of all freshwater used worldwide and 45% in Asia. Turning away from permanently flooded rice cropping systems for mitigating future water scarcity and reducing methane emissions, however, will alter a variety of ecosystem services with potential adverse effects to both the environment and agricultural production. Moreover, implementing systems that alternate between flooded and non-flooded crops increases the risk of disruptive effects. The multi-disciplinary DFG research unit ICON aims at exploring and quantifying the ecological consequences of altered water regimes (flooded vs. non-flooded), crop diversification (irrigated rice vs. aerobic rice vs. maize), and different fertilization strategies (conventional, site-specific, and zero N fertilization). ICON particularly focuses on the biogeochemical cycling of carbon and nitrogen, green-house gas (GHG) emissions, water balance, soil biotic processes and other important ecosystem services. The overarching goal is to provide the basic process understanding that is necessary for balancing the revenues and environmental impacts of high-yield rice cropping systems while maintaining their vital ecosystem services. To this aim, a large-scale field experiment has been established at the experimental farm of the International Rice Research Institute (IRRI, Philippines). Ultimately, the experimental results are analyzed in the context of management scenarios by an integrated modeling of crop development (ORYZA), carbon and nitrogen cycling (MoBiLE-DNDC), and water fluxes (CMF), providing the basis for developing pathways to a conversion of rice-based systems towards higher yield potentials under minimized environmental impacts. In our presentation, we demonstrate the set-up of the controlled large-scale field experiment for simultaneous assessment of carbon and nitrogen fluxes and water budgets. We show and discuss first results for: - Quantification and assessment of the net-fluxes of CH4

  18. Aluminium tolerance in rice is antagonistic with nitrate preference and synergistic with ammonium preference.

    Science.gov (United States)

    Zhao, Xue Qiang; Guo, Shi Wei; Shinmachi, Fumie; Sunairi, Michio; Noguchi, Akira; Hasegawa, Isao; Shen, Ren Fang

    2013-01-01

    Acidic soils are dominated chemically by more ammonium and more available, so more potentially toxic, aluminium compared with neutral to calcareous soils, which are characterized by more nitrate and less available, so less toxic, aluminium. However, it is not known whether aluminium tolerance and nitrogen source preference are linked in plants. This question was investigated by comparing the responses of 30 rice (Oryza sativa) varieties (15 subsp. japonica cultivars and 15 subsp. indica cultivars) to aluminium, various ammonium/nitrate ratios and their combinations under acidic solution conditions. indica rice plants were generally found to be aluminium-sensitive and nitrate-preferring, while japonica cultivars were aluminium-tolerant and relatively ammonium-preferring. Aluminium tolerance of different rice varieties was significantly negatively correlated with their nitrate preference. Furthermore, aluminium enhanced ammonium-fed rice growth but inhibited nitrate-fed rice growth. The results suggest that aluminium tolerance in rice is antagonistic with nitrate preference and synergistic with ammonium preference under acidic solution conditions. A schematic diagram summarizing the interactions of aluminium and nitrogen in soil-plant ecosystems is presented and provides a new basis for the integrated management of acidic soils.

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

    Science.gov (United States)

    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.

  20. Current Status of Conventional and Molecular Interventions for Blast Resistance in Rice

    Directory of Open Access Journals (Sweden)

    Deepti Srivastava

    2017-11-01

    Full Text Available Pyricularia oryzae anamorph of Magnaporthe oryzae is one of the most notorious fungal pathogens causing severe economic loss in rice production worldwide. Various methods, viz. cultural, biological and molecular approaches, are utilized to counteract this pathogen. Moreover, some tolerant or resistant rice varieties have been developed with the help of breeding programmes. Isolation and molecular characterization of different blast resistance genes now open the gate for new possibilities to elucidate the actual allelic variants of these genes via various molecular breeding and transgenic approaches. However, the behavioral pattern of this fungus breakups the resistance barriers in the resistant or tolerant rice varieties. This host-pathogen barrier will be possibly countered in future research by comparative genomics data from available genome sequence data of rice and M. oryzae for durable resistance. Present review emphasized fascinating recent updates, new molecular breeding approaches, transgenic and genomics approaches (i.e. miRNA and genome editing for the management of blast disease in rice. The updated information will be helpful for the durable, resistance breeding programme in rice against blast pathogen.

  1. A practicable detection system for genetically modified rice by SERS-barcoded nanosensors.

    Science.gov (United States)

    Chen, Kun; Han, Heyou; Luo, Zhihui; Wang, Yanjun; Wang, Xiuping

    2012-04-15

    Since the global cultivation of genetically modified crops constantly expands, it remains a high demand to establish different ways to sort food and feed that consist or contain genetically modified organisms. Surface-enhanced Raman scattering (SERS) spectroscopy is a flexible tool for biological analysis due to its excellent properties for detecting wide varieties of target biomolecules including nucleic acids. In the present study, a SERS-barcoded nanosensor was developed to detect Bacillus thuringiensis (Bt) gene-transformed rice expressing insecticidal proteins. The barcoded sensor was designed by encapsulation of gold nanoparticles with silica and conjugation of oligonucleotide strands for targeting DNA strands. The transition between the cry1A(b) and cry1A(c) fusion gene sequence was used to construct a specific SERS-based detection method with a detection limit of 0.1 pg/mL. In order to build the determination models to screen transgene, a series mixture of Bt rice and normal rice were prepared for SERS assay, and the limit of detection was 0.1% (w/w) transgenic Bt rice relative to normal rice. The sensitivity and accuracy of the SERS-based assay was comparable with real-time PCR. The SERS-barcoded analytical method would provide precise detection of transgenic rice varieties but also informative supplement to avoid false positive outcomes. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  2. Against the grain: safeguarding rice from rice blast disease.

    Science.gov (United States)

    Skamnioti, Pari; Gurr, Sarah J

    2009-03-01

    Rice is the staple diet of more than three billion people. Yields must double over the next 40 years if we are to sustain the nutritional needs of the ever-expanding global population. Between 10% and 30% of the annual rice harvest is lost due to infection by the rice blast fungus Magnaporthe oryzae. Evaluation of genetic and virulence diversity of blast populations with diagnostic markers will aid disease management. We review the M. oryzae species-specific and cultivar-specific avirulence determinants and evaluate efforts towards generating durable and broad-spectrum resistance in single resistant cultivars or mixtures. We consider modern usage of fungicides and plant defence activators, assess the usefulness of biological control and categorize current approaches towards blast-tolerant genetically modified rice.

  3. COMPETITIVENESS OF NIGERIAN RICE AND MAIZE PRODUCTION ECOLOGIES: A POLICY ANALYSIS APPROACH

    Directory of Open Access Journals (Sweden)

    Victor Olusegun Okoruwa

    2011-05-01

    Full Text Available The Nigerian rice and maize sectors are faced with decreasing supply and increasing demand as rice and maize have taken a strategic place of other staples leading to excessive importation and increasing government intervention. This study therefore assesses the competitiveness of Nigerian rice and maize production ecologies using the policy analysis matrix (PAM on a sample of 122 farmers. Results of the PAM revealed that outputs from the production ecologies are taxed. This is further confirmed by the Effective protection coefficient (EPC and Subsidy ratio to producers (SRP values, however, the production ecologies are subsidized on the use of tradable inputs. The production ecologies show a strong competitiveness at the farm level (under irrigated rice, upland rice and upland maize and a strong comparative advantage. Sensitivity analysis indicated that a 50 percent increase in output and a 13.3 percent depreciation of the domestic currency will increase competitiveness and comparative advantage of rice and maize production in all ecologies. The study recommends that government should ensure a level of policy stability in the rice and maize sectors, assist farmers with irrigated water scheme to ensure constant water supply, and increase the level of output through provision of improved seed varieties.

  4. The Association of Bread and Rice with Metabolic Factors in Type 2 Diabetic Patients.

    Science.gov (United States)

    Akhoundan, Mahdieh; Shadman, Zhaleh; Jandaghi, Parisa; Aboeerad, Maryam; Larijani, Bagher; Jamshidi, Zahra; Ardalani, Hamidreza; Khoshniat Nikoo, Mohsen

    2016-01-01

    Carbohydrates are shown to have an important role in blood glucose control, type 2 diabetes and cardiovascular diseases risk. This is even more challenging when considering populations consuming refined grains diets. Bread and rice are staple foods which supply main proportion of Iranian calorie intake. This study was designed to investigate the effect of bread and rice intake on blood glucose control, lipid profile and anthropometric measurements in Iranian type 2 diabetic patients. 426 patients with type 2 diabetes were included in this study. Anthropometric measurements were done using standard methods. Dietary information was assessed by a valid and reliable food frequency questionnaire (FFQ). Fasting blood glucose (FBG), glycated hemoglobin (HbA1c), serum triglycride (TG), total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol were examined after 12-hour fasting. The results represented that people in the highest tertile compared to the lowest tertile of calorie adjusted total bread intake have higher FBG. FBG in the highest tertile of calorie adjusted total bread-rice intake was also significantly higher than the lowest. The association remained significant after adjusting for potential confounders. Rice intake showed no association with cardio-metabolic risk factors. We founded that higher total bread intake and total bread-rice intake were associated with FBG in type 2 diabetic patients whereas rice intake was not associated with glucose and lipid profile. This result should be confirmed in prospective studies, considering varieties, glycemic index (GI), glycemic load (GL) and cooking method of bread and rice.

  5. Ohmic heating as a pre-treatment in solvent extraction of rice bran.

    Science.gov (United States)

    Nair, Gopu Raveendran; Divya, V R; Prasannan, Liji; Habeeba, V; Prince, M V; Raghavan, G S V

    2014-10-01

    Rice bran, which is one of the major by products of paddy contain high quality proteins and edible oil apart from fibre, ash and NFE (nitrogen free extract). The existing solvent extraction method employs n-hexane as the most viable solvent for the extraction of oil from rice bran. But the high cost and scarce availability of n-hexane resulted in uneconomical extraction of rice bran oil. In this study, rice bran was ohmically heated for different time periods(1, 2 and 3 min) with different current values (5, 15 and 20 A) and with different concentration of sodium chloride (1 M, 0.1 M and 0.01 M) as conducting medium. The ohmically heated rice bran was subjected to extraction studies. Ohmic heating of rice bran of paddy varieties Red Triveni and Basmati reduced the extraction time by nearly 75 % and 70 % respectively and gave a maximum quantity of oil extracted when compared to bran, which was not ohmically heated. From the experiments with varying concentrations, residence time of ohmic heating and currents, it was found that ohmically heating the rice bran with 1 M sodium chloride solution and with a current value of 20 A for 3 min gave maximum oil extraction with minimum extraction time.

  6. Screening and Expression of a Silicon Transporter Gene (Lsi1) in Wild-Type Indica Rice Cultivars

    Science.gov (United States)

    Abiri, Rambod; Kalhori, Nahid; Atabaki, Narges

    2017-01-01

    Silicon (Si) is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties. PMID:28191468

  7. GENETIC BASE OF CUBAN RICE VARIETIES RELEASED BETWEEN 1972 AND 1993

    OpenAIRE

    FUENTES, J.L.; Isis M. Ramírez; J. Arteche; J. E. Deus; Suárez, E.; Alonso, R; Violeta Puldón; P. J. Gómez; María T. Cornide

    2003-01-01

    En el presente trabajo se estudió la base genética del programa de mejoramiento arrocero en Cuba y el parentesco de las variedades de arroz obtenidas para la producción entre 1972 y 1993. Los resultados mostraron que la base genética del programa proviene de 32 cultivares ancestrales, 18 de estos contribuyeron durante todo este período y por ello se consideraron como el núcleo de la constitución genética del arroz en Cuba. La base genética fue parcialmente coincidente con la de otros programa...

  8. Response of high yielding rice varieties to NaCl salinity in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-05

    Nov 5, 2008 ... in the experiment include: Dasht, Khazar, Kadous, Nemat, Neda,. Fajr, Shafagh and Sahel. To obtain the accurate result and exclude any unwanted and interfering variable in the environment and to minimize their effects, the experiment was conducted in a highly controlled greenhouse. The greenhouse ...

  9. Genetic variation in southern USA rice genotypes for salinity tolerance

    Directory of Open Access Journals (Sweden)

    Teresa B De Leon

    2015-05-01

    Full Text Available The success of a rice breeding program in developing salt tolerant varieties depends on genetic variation and the salt stress response of adapted and donor rice germplasm. In this study, we used a combination of morphological and physiological traits in multivariate analyses to elucidate the phenotypic and genetic variation in salinity tolerance of thirty Southern USA rice genotypes, along with nineteen donor genotypes with varying degrees of tolerance. Significant genotypic variation and correlations were found among the salt injury score (SIS, ion leakage, chlorophyll reduction, shoot length reduction, shoot K+ concentration, and shoot Na+/K+ ratio. Using these parameters, the combined methods of cluster analysis and discriminant analysis validated the salinity response of known genotypes and classified most of the USA varieties into sensitive groups, except for three and seven varieties placed in the tolerant and moderately tolerant groups, respectively. Discriminant function and MANOVA delineated the differences in tolerance and suggested no differences between sensitive and highly sensitive groups. DNA profiling using simple sequence repeat markers showed narrow genetic diversity among USA genotypes. However, the overall genetic clustering was mostly due to subspecies and grain type differentiation and not by varietal grouping based on salinity tolerance. Among the donor genotypes, Nona Bokra, Pokkali, and its derived breeding lines remained the donors of choice for improving salinity tolerance during the seedling stage. However, due to undesirable agronomic attributes and photosensitivity of these donors, alternative genotypes such as TCCP266, Geumgangbyeo, and R609 are recommended as useful and novel sources of salinity tolerance for USA rice breeding programs.

  10. Studies on the Pasting and Rheology of Rice Starch with Different Protein Residual

    Science.gov (United States)

    Lin, Qinlu; Liu, Zhonghua; Xiao, Huaxi; Li, Lihui; Yu, Fengxiang; Tian, Wei

    Indica rice starch and japonica rice starch were used in the study. The protein contents of the two rice variety were respectively 0.43%, 0.62%, 0.84%, 1.08%, 1.25%. The pasting and rheological properties of samples were determined with Rapid Visco Analyzer and dynamic rheometer. The results indicated that, with the increase of protein content, the peak viscosity, breakdown viscosity and final viscosity of rice starch paste decreased, the setback viscosity increased and the pasting temperature did not change significantly. With the increase of protein content, the consistency coefficient of starch decreased, the corresponding yield stress also decreased, however, the flow behavior index increased with the decrease of consistency coefficient. At same temperature, the storage modulus G' was greater when the protein content was higher.

  11. Process arrangements for variety, retention, and selection

    NARCIS (Netherlands)

    De Bruijn, J.A.; Ten Heuvelhof, E.F.

    2004-01-01

    This article argues that process management aimed at introducing variety, retention, and selection into complex decision-making processes can make a substantial contribution to improving them. It also describes process arrangements for variety, retention, and selection.

  12. Allele mining and selective patterns of Pi9 gene in a set of rice landraces from India

    Directory of Open Access Journals (Sweden)

    Jahangir Imam

    2016-12-01

    Full Text Available Allelic variants of the broad-spectrum blast resistance gene, Pi9 (NBS-LRR region have been analyzed in Indian rice landraces. They were selected from the list of 338 rice landraces phenotyped in the rice blast nursery at central Rainfed Upland Rice Research Station, Hazaribag. Six of them were further selected on the basis of their resistance and susceptible pattern for virulence analysis and selective pattern study of Pi9 gene. The sequence analysis and phylogenetic study illustrated that such sequences are vastly homologous and clustered into two groups. All the blast resistance Pi9 alleles were grouped into one cluster, whereas Pi9 alleles of susceptible landraces formed another cluster even though these landraces have a low level of DNA polymorphisms. A total number of 136 polymorphic sites comprising of transitions, transversions and InDels were identified in the 2.9kb sequence of Pi9 alleles. Lower variation in the form of mutations (77 (Transition + Transversion, and InDels (59 were observed in the Pi9 alleles isolated from rice landraces studied. The results showed that the Pi9 alleles of the selected rice landraces were less variable, suggesting that the rice landraces would have been exposed to less number of pathotypes across the country. The positive Tajima’s D (0.33580, P > 0.10 (not significant was observed among the seven rice landraces, which suggests the balancing selection of Pi9 alleles. The value of synonymous substitution (-0.43337 was less than the non-synonymous substitution (0.78808. The greater non-synonymous substitution than the synonymous means that the coding region, mainly the LRR domain was under diversified selection. In this study, the Pi9 gene has been subjected to balancing selection with low nucleotide diversity which is different from the earlier reports, this may be because of the closeness of the rice landraces, cultivated in the same region and under low pathotype pressure.

  13. Managing Water and Soils to Achieve Adaptation and Reduce Methane Emissions and Arsenic Contamination in Asian Rice Production

    Directory of Open Access Journals (Sweden)

    Dennis Wichelns

    2016-04-01

    Full Text Available Rice production is susceptible to damage from the changes in temperature and rainfall patterns, and in the frequency of major storm events that will accompany climate change. Deltaic areas, in which millions of farmers cultivate from one to three crops of rice per year, are susceptible also to the impacts of a rising sea level, submergence during major storm events, and saline intrusion into groundwater and surface water resources. In this paper, I review the current state of knowledge regarding the potential impacts of climate change on rice production and I describe adaptation measures that involve soil and water management. In many areas, farmers will need to modify crop choices, crop calendars, and soil and water management practices as they adapt to climate change. Adaptation measures at the local, regional, and international levels also will be helpful in moderating the potential impacts of climate change on aggregate rice production and on household food security in many countries. Some of the changes in soil and water management and other production practices that will be implemented in response to climate change also will reduce methane generation and release from rice fields. Some of the measures also will reduce the uptake of arsenic in rice plants, thus addressing an important public health issue in portions of South and Southeast Asia. Where feasible, replacing continuously flooded rice production with some form of aerobic rice production, will contribute to achieving adaptation objectives, while also reducing global warming potential and minimizing the risk of negative health impacts due to consumption of arsenic contaminated rice.

  14. Rice Husk Filled Polymer Composites

    National Research Council Canada - National Science Library

    Arjmandi, Reza; Hassan, Azman; Majeed, Khaliq; Zakaria, Zainoha

    2015-01-01

      Natural fibers from agricultural wastes are finding their importance in the polymer industry due to the many advantages such as their light weight, low cost and being environmentally friendly. Rice husk (RH...

  15. Red Yeast Rice: An Introduction

    Science.gov (United States)

    ... mg twice daily) in patients with previous statin intolerance . American Journal of Cardiology . 2010;105:198–204. ... to Avoid Red Yeast Rice Products Promoted on Internet as Treatments for High Cholesterol: Products Found to ...

  16. Rice vaikib salavanglaist / Tõnis Erilaid

    Index Scriptorium Estoniae

    Erilaid, Tõnis, 1943-

    2005-01-01

    Euroopasse visiidile sõitev USA välisminister Condoleezza Rice külastab Saksamaad, Rumeeniat, Ukrainat ja Belgiat. Süüdistusi CIA lennukite maandumiste ja salavanglate kohta ei olevat tal kavas kommenteerida

  17. DNA tagging of blast resistant gene(s in three Brazilian rice cultivars

    Directory of Open Access Journals (Sweden)

    S.S. Sandhu

    2003-12-01

    Full Text Available Rice blast is the most important fungal disease of rice and is caused by Pyricularia oryzae Sacc. (Telomorph Magnoporthe grisea Barr.. Seven randomly amplified polymorphic DNA (RAPD markers OPA5, OPG17, OPG18, OPG19, OPF9, OPF17 and OPF19 showed very clear polymorphism in resistant cultivar lines which differed from susceptible lines. By comparing different susceptible lines, nine DNA amplifications of seven primers (OPA5(1000, OPA5(1200, OPG17(700, OPG18(850, OPG19(500, OPG19(600, OPF9(600, OPF17(1200 and OPF19(600 were identified as dominant markers for the blast resistant gene in resistant cultivar lines. These loci facilitate the indirect scoring of blast resistant and blast susceptible genotypes. The codomine RAPDs markers will facilitate marker-assisted selection of the blast resistant gene in two blast resistant genotypes of rice (Labelle and Line 11 and will be useful in rice breeding programs.

  18. Korean Adults' Attitudes towards Varieties of English

    OpenAIRE

    Kim, Young Soo

    2007-01-01

    This study investigates 43 Korean adults’ attitudes towards native and non-native varieties of English in relation to the perspective of EIL (English as an international language). This study addresses three research questions: 1) do Korean adults prefer certain varieties of English? 2) do Korean adults at least accept non-native varieties of English?, and 3) are Korean adults aware of different varieties of English? In order to examine participants’ language attitudes, this study employed bo...

  19. In silico Analysis of osr40c1 Promoter Sequence Isolated from Indica Variety Pokkali

    Directory of Open Access Journals (Sweden)

    W.S.I. de Silva

    2017-07-01

    Full Text Available The promoter region of a drought and abscisic acid (ABA inducible gene, osr40c1, was isolated from a salt-tolerant indica rice variety Pokkali, which is 670 bp upstream of the putative translation start codon. In silico promoter analysis of resulted sequence showed that at least 15 types of putative motifs were distributed within the sequence, including two types of common promoter elements, TATA and CAAT boxes. Additionally, several putative cis-acing regulatory elements which may be involved in regulation of osr40c1 expression under different conditions were found in the 5′-upstream region of osr40c1. These are ABA-responsive element, light-responsive elements (ATCT-motif, Box I, G-box, GT1-motif, Gap-box and Sp1, myeloblastosis oncogene response element (CCAAT-box, auxin responsive element (TGA-element, gibberellin-responsive element (GARE-motif and fungal-elicitor responsive elements (Box E and Box-W1. A putative regulatory element, required for endosperm-specific pattern of gene expression designated as Skn-1 motif, was also detected in the Pokkali osr40c1 promoter region. In conclusion, the bioinformatic analysis of osr40c1 promoter region isolated from indica rice variety Pokkali led to the identification of several important stress-responsive cis-acting regulatory elements, and therefore, the isolated promoter sequence could be employed in rice genetic transformation to mediate expression of abiotic stress induced genes.