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Sample records for oryza sativa populations

  1. Mapping of Novel QTL Regulating Grain Shattering Using Doubled Haploid Population in Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Gyu-Ho Lee

    2016-01-01

    Full Text Available The critical evolutionary step during domestication of major cereals was elimination of seed shattering because the easy-to-shatter trait in wild relatives results in a severe reduction in yield. In this study, we analyzed the QTLs associated with shattering employing a high-density genetic map in doubled haploid (DH population of rice (Oryza sativa L.. A genetic linkage map was generated with 217 microsatellite markers spanning 2082.4 cM and covering 12 rice chromosomes with an average interval of 9.6 cM between markers based on 120 DHLs derived from a cross between Cheongcheong indica type cultivar and Nagdong japonica type cultivar. In the QTL analysis, five QTLs pertaining to the breaking tensile strength (BTS were detected in 2013 and 2015. Two regions of the QTLs related to BTS on chromosome 1 and chromosome 6 were detected. Several important genes are distributed in 1 Mbp region of the QTL on chromosome 6 and they are related to the formation of abscission layer. We decide to name this QTL qSh6 and the candidate genes in the qSh6 region can be employed usefully in further research for cloning.

  2. Genetic diversity in Oryza glumaepatula wild rice populations in Costa Rica and possible gene flow from O. sativa.

    Science.gov (United States)

    Fuchs, Eric J; Meneses Martínez, Allan; Calvo, Amanda; Muñoz, Melania; Arrieta-Espinoza, Griselda

    2016-01-01

    Wild crop relatives are an important source of genetic diversity for crop improvement. Diversity estimates are generally lacking for many wild crop relatives. The objective of the present study was to analyze how genetic diversity is distributed within and among populations of the wild rice species Oryza glumaepatula in Costa Rica. We also evaluated the likelihood of gene flow between wild and commercial rice species because the latter is commonly sympatric with wild rice populations. Introgression may change wild species by incorporating alleles from domesticated species, increasing the risk of losing original variation. Specimens from all known O. glumaepatula populations in Costa Rica were analyzed with 444 AFLP markers to characterize genetic diversity and structure. We also compared genetic diversity estimates between O. glumaepatula specimens and O. sativa commercial rice. Our results showed that O. glumaepatula populations in Costa Rica have moderately high levels of genetic diversity, comparable to those found in South American populations. Despite the restricted distribution of this species in Costa Rica, populations are fairly large, reducing the effects of drift on genetic diversity. We found a dismissible but significant structure (θ = 0.02 ± 0.001) among populations. A Bayesian structure analysis suggested that some individuals share a significant proportion of their genomes with O. sativa. These results suggest that gene flow from cultivated O. sativa populations may have occurred in the recent past. These results expose an important biohazard: recurrent hybridization may reduce the genetic diversity of this wild rice species. Introgression may transfer commercial traits into O. glumaepatula, which in turn could alter genetic diversity and increase the likelihood of local extinction. These results have important implications for in situ conservation strategies of the only wild populations of O. glumaepatula in Costa Rica.

  3. Evaluation of Oryza sativa x O. glaberrima derived progenies for ...

    African Journals Online (AJOL)

    USER

    2010-06-28

    Jun 28, 2010 ... The genus Oryza has two cultivated species, Asian rice (Oryza sativa L.) and African rice (Oryza glaberrima Steud.) and 22 wild species. O. glaberrima is low yielding but has useful genes for resistance to biotic and abiotic stresses. Introgression lines derived from backcrossing of O. sativa x O. glaberrima,.

  4. Genetic variation for traits associated with domestication identified in a cultivated rice, Nipponbare (Oryza sativa ssp. japonica) x ancestral rice, O. nivara, mapping population

    Science.gov (United States)

    Oryza nivara, the progenitor of cultivated rice, O. sativa, has been the source of novel alleles for resistance to biotic and abiotic stresses, as well as for yield improvement. Many of these alleles were lost during the domestication process. To determine the molecular changes that occurred during ...

  5. Genetic Diversity and Phenotypic Variation in an Introgression Line Population Derived from an Interspecific Cross between Oryza glaberrima and Oryza sativa.

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    Caijin Chen

    Full Text Available The introduction of closely related species genomic fragments is an effective way to enrich genetic diversity and creates new germplasms in crops. Here, we studied the genetic diversity of an introgression line (IL population composed of 106 ILs derived from an interspecific tetra cross between O. glaberrima and O. sativa (RAM3/Jin23B//Jin23B///YuetaiB. The proportion of O. glaberrima genome (PGG in the ILs ranged from 0.3% to 36.7%, with an average value of 12.32% which is close to the theoretically expected proportion. A total of 250 polymorphic alleles were amplified by 21 AFLP primer combinations with an average of 12 alleles per primer. Population structure analysis revealed that the IL population can be divided into four genetically distinct subpopulations. Both principal component analysis and neighbor-joining tree analysis showed that ILs with a higher PGG displayed greater genetic diversity. Canonical discriminant analysis identified six phenotypic traits (plant height, yield per plant, filled grain percentage, panicle length, panicle number and days to flowering as the main discriminatory traits among the ILs and between the subpopulations and showed significant phenotypic distances between subpopulations. The effects of PGG on phenotypic traits in the ILs were estimated using a linear admixed model, which showed a significant positive effect on grain yield per plant (0.286±0.117, plant height (0.418 ± 0.132, panicle length (0.663 ± 0.107, and spikelet number per panicle (0.339 ± 0.128, and a significant negative effect on filled grain percentage (-0.267 ± 0.123 and days to flowering (-0.324 ± 0.075. We found that an intermediate range (10% - 20% of PGG was more effective for producing ILs with favorable integrated agronomic traits. Our results confirm that construction of IL population carrying O. glaberrima genomic fragments could be an effective approach to increase the genetic diversity of O. sativa genome and an appropriate

  6. Molecular Mapping of QTLs for Yield and Yield-Related Traits in Oryza sativa cv Swarna × O. nivara (IRGC81848 Backcross Population

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    B.P. MALLIKARJUNA SWAMY

    2011-09-01

    Full Text Available Advanced backcross QTL analysis was used to identify QTLs for seven yield and yield-related traits in a BC2F2 population from the cross between a popular Oryza sativa cv Swarna and O. nivara IRGC81848. Transgressive segregants with more than 15% increased effect over Swarna were observed for all the traits except days to heading and days to 50% flowering. Thirty QTLs were detected for seven yield and yield-related traits using interval and composite interval mapping. Enhancing alleles at 13 (45% of these QTLs were derived from O. nivara, and enhancing alleles at all the QTLs for stem diameter and rachis diameter were derived from O. nivara. Three stem diameter QTLs, two rachis diameter QTLs and one number of secondary branches QTL identified by both Interval and composite interval mapping contributed more than 15% of the total phenotypic variance. The QTL epistasis was significant for stem diameter and plot yield. The most significant QTLs qSD7.2, qSD8.1 and qSD9.1 for stem diameter, qRD9.1 for rachis diameter and qNSB1.1 for number of secondary branches are good targets to evaluate their use in marker-assisted selection. O. nivara is a good source of novel alleles for yield related traits and reveals major effect QTLs suitable for marker-assisted selection.

  7. Construction of six Oryza sativa x O. rufipogon Chromosome Segment Substitution Line (CSSL) Libraries

    Science.gov (United States)

    Transgressive variation has been observed in rice (Oryza sativa) as an increase in grain yield and attributed to the ancestral parent, O. rufipogon, in mapping populations developed from several adapted rice varieties crossed with a single O. rufipogon accession. To explore this phenomenon of transg...

  8. Variation of photosynthetic tolerance of rice cultivars (Oryza sativa L ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-01

    Mar 1, 2010 ... (Oryza sativa L.) to chilling temperature in the light. Xia Li*, Kun Cao, Chao .... 2 mol) formed red-brown trimethine that can be detected quantitatively with spectrophoto- ..... ses through the generation of appropriate signals (H2O2) and the balance ..... was under weak light intensity (Murata, 1989). Light.

  9. Molecular and genetic characterization of OSH6 ( Oryza sativa ...

    African Journals Online (AJOL)

    Genetic studies of dissociation (Ds) insertion mutant rice plants indicated that ectopic expression of truncated OSH6 (Oryza sativa Homeobox 6) mRNA may be responsible for the mutant phenotype of knotted leaf formation at the peduncle. Additionally, ectopic expression of truncated OSH6 mRNA in the OSH6-Ds mutant ...

  10. Development and Identification of Introgression Lines from Cross of Oryza sativa and Oryza minuta

    Institute of Scientific and Technical Information of China (English)

    GUO Si-bin; WEI Yu; LI Xiao-qiong; LIU Kai-qiang; HUANG Feng-kuan; CHEN Cai-hong; GAO Guo-qing

    2013-01-01

    Introgression line population is effectively used in mapping quantitative trait loci (QTLs),identifying favorable genes,discovering hidden genetic variation,evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research.In this study,an advanced backcross and consecutive selfing strategy was used to develop introgression lines (ILs),which derived from an accession of Oryza minuta (accession No.101133) with BBCC genome,as the donor,and an elite indica cultivar IR24 (O.sativa),as the recipient.Introgression segments from O.minuta were screened using 164 polymorphic simple sequence repeat (SSR) markers in the genome of each IL.Introgressed segments carried by 131 ILs covered the whole O.sativa genome.The average number of homozygous O.minuta segments per introgression line was about 9.99.The average length of introgressed segments was approximate 14.78 cM,and about 79.64%of these segments had sizes less than 20 cM.In the genome of each introgression line,the O.minuta chromosomal segments harbored chromosomal fragments of O.sativa ranging from 1.15% to 27.6%,with an overall average of 8.57%.At each locus,the ratio of substitution of O.minuta alleles had a range of 1.5%-25.2%,with an average of 8.3% Based on the evaluation of the phenotype of these ILs,a wide range of alterations in morphological and yield-related traits were found.After inoculation,ILs 41,11 and 7 showed high resistance to bacterial blight,brown planthopper and whitebacked planthopper,respectively.These O.minuta-O.sativa ILs will serve as genetic materials for identifying and using favorable genes from O.minuta.

  11. Genetic Diversity and Population Structure in Aromatic and Quality Rice (Oryza sativa L. Landraces from North-Eastern India.

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    Somnath Roy

    Full Text Available The North-eastern (NE India, comprising of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura, possess diverse array of locally adapted non-Basmati aromatic germplasm. The germplasm collections from this region could serve as valuable resources in breeding for abiotic stress tolerance, grain yield and cooking/eating quality. To utilize such collections, however, breeders need information about the extent and distribution of genetic diversity present within collections. In this study, we report the result of population genetic analysis of 107 aromatic and quality rice accessions collected from different parts of NE India, as well as classified these accessions in the context of a set of structured global rice cultivars. A total of 322 alleles were amplified by 40 simple sequence repeat (SSR markers with an average of 8.03 alleles per locus. Average gene diversity was 0.67. Population structure analysis revealed that NE Indian aromatic rice can be subdivided into three genetically distinct population clusters: P1, joha rice accessions from Assam, tai rices from Mizoram and those from Sikkim; P2, aromatic rice accessions from Nagaland; and P3, chakhao rice germplasm from Manipur [corrected]. Pair-wise FST between three groups varied from 0.223 (P1 vs P2 to 0.453 (P2 vs P3. With reference to the global classification of rice cultivars, two major groups (Indica and Japonica were identified in NE Indian germplasm. The aromatic accessions from Assam, Manipur and Sikkim were assigned to the Indica group, while the accessions from Nagaland exhibited close association with Japonica. The tai accessions of Mizoram along with few chakhao accessions collected from the hill districts of Manipur were identified as admixed. The results highlight the importance of regional genetic studies for understanding diversification of aromatic rice in India. The data also suggest that there is scope for exploiting the genetic diversity of

  12. Genetic Diversity and Population Structure in Aromatic and Quality Rice (Oryza sativa L.) Landraces from North-Eastern India.

    Science.gov (United States)

    Roy, Somnath; Banerjee, Amrita; Mawkhlieng, Bandapkuper; Misra, A K; Pattanayak, A; Harish, G D; Singh, S K; Ngachan, S V; Bansal, K C

    2015-01-01

    The North-eastern (NE) India, comprising of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura, possess diverse array of locally adapted non-Basmati aromatic germplasm. The germplasm collections from this region could serve as valuable resources in breeding for abiotic stress tolerance, grain yield and cooking/eating quality. To utilize such collections, however, breeders need information about the extent and distribution of genetic diversity present within collections. In this study, we report the result of population genetic analysis of 107 aromatic and quality rice accessions collected from different parts of NE India, as well as classified these accessions in the context of a set of structured global rice cultivars. A total of 322 alleles were amplified by 40 simple sequence repeat (SSR) markers with an average of 8.03 alleles per locus. Average gene diversity was 0.67. Population structure analysis revealed that NE Indian aromatic rice can be subdivided into three genetically distinct population clusters: P1, joha rice accessions from Assam, tai rices from Mizoram and those from Sikkim; P2, aromatic rice accessions from Nagaland; and P3, chakhao rice germplasm from Manipur [corrected]. Pair-wise FST between three groups varied from 0.223 (P1 vs P2) to 0.453 (P2 vs P3). With reference to the global classification of rice cultivars, two major groups (Indica and Japonica) were identified in NE Indian germplasm. The aromatic accessions from Assam, Manipur and Sikkim were assigned to the Indica group, while the accessions from Nagaland exhibited close association with Japonica. The tai accessions of Mizoram along with few chakhao accessions collected from the hill districts of Manipur were identified as admixed. The results highlight the importance of regional genetic studies for understanding diversification of aromatic rice in India. The data also suggest that there is scope for exploiting the genetic diversity of aromatic and

  13. Assessment and genetic analysis of heavy metal content in rice grain using an Oryza sativa × O. rufipogon backcross inbred line population.

    Science.gov (United States)

    Huang, De-Run; Fan, Ye-Yang; Hu, Biao-Lin; Xiao, Ye-Qing; Chen, Da-Zhou; Zhuang, Jie-Yun

    2018-03-01

    Heavy metal accumulation in rice is a growing concern for public health. Backcross inbred lines derived from an interspecific cross of Oryza sativa × O. rufipogon were grown in two distinct ecological locations (Hangzhou and Lingshui, China). The objective of this study was to characterise the contents of heavy metal in rice grains, and to identify quantitative trait loci (QTLs) for heavy metal contents. The contents of Ni, As, Pb, Cr and Hg in milled rice showed a significant decline as compared with those in brown rice, whereas the content of Cd showed little change. The concentration of heavy metal in rice grain varied greatly between the two environments. A total of 24 QTLs responsible for heavy metal contents were detected, including two for both the brown and milled rice, 13 for brown rice only, and nine for milled rice only. All the QTLs except two had the enhancing alleles derived from O. rufipogon. Sixteen QTLs were clustered in six chromosomal regions. Environmental variation plays an important role in the heavy metal contents in rice grain. QTLs detected in this study might be useful for breeding rice varieties with low heavy metal content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Sensory acceptability evaluation of irradiated rice, oryza sativa indica

    International Nuclear Information System (INIS)

    Loaharanu, S.; Sutantawong, M.; Ungsunanatawiwat, A.

    1971-01-01

    The non-glutinous and glutinous types of polished rice, Oryza sativa indica were subjected to gamma rays at ambient temperature and stored at 27+-1 0 C for one week. The irradiated rice was cooked and tasted by members of trained panel. Using Hedonic scale and Triangle test, the acceptability of irradiated rice was justified. Gamma irradiation up to 100 krads did not significantly cause off-color, off-odor and off flavor in irradiated non-glutino rice. Glutinous rice irradiated at 60 krads could not be significantly differentiated from non-irradiated sample

  15. A genome browser database for rice (Oryza sativa) and Chinese ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... sativa) and Chinese cabbage (Brassica rapa) genomes. The genome ... tant staple food for a large part of the world's human population. .... some banding region for selection and the overview panel shows the location of ...

  16. Growth responses of NaCl stressed rice (Oryza sativa L.) plants ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-27

    Sep 27, 2010 ... 3Department of Statistics, University of Sindh Jamshoro, Pakistan. 4Mityari Sugar Mills ... Key words: Oryza sativa L., seedling biomass, epidermal cells, proline content. ... Attempts to reduce the soil salinity, using mechanical.

  17. Oxygen dynamics in submerged rice (Oryza sativa L.)

    DEFF Research Database (Denmark)

    Colmer, Timothy D.; Pedersen, Ole

    2008-01-01

    Complete submergence of plants prevents direct O2 and CO2 exchange with air. Underwater photosynthesis can result in marked diurnal changes in O2 supply to submerged plants. Dynamics in pO2 had not been measured directly for submerged rice (Oryza sativa), but in an earlier study, radial O2 loss...... from roots showed an initial peak following shoot illumination.  O2 dynamics in shoots and roots of submerged rice were monitored during light and dark periods, using O2 microelectrodes. Tissue sugar concentrations were also measured.  On illumination of shoots of submerged rice, pO2 increased rapidly...... of magnitude higher than in darkness, enhancing also pO2 in roots.The initial peak in pO2 following illumination of submerged rice was likely to result from high initial rates of net photosynthesis, fuelled by CO2 accumulated during the dark period. Nevertheless, since sugars decline with time in submerged...

  18. Correlation between temperature and phenology prediction error in rice (Oryza sativa L.)

    NARCIS (Netherlands)

    Oort, van P.A.J.; Zhang, T.; Vries, de M.E.; Heinemann, A.B.; Meinke, H.B.

    2011-01-01

    For rice (Oryza sativa L.), simulation models like ORYZA2000 and CERES-Rice have been used to explore adaptation options to climate change and weather-related stresses (drought, heat). Output of these models is very sensitive to accurate modelling of crop development, i.e. phenology. What has to

  19. Could abiotic stress tolerance in wild relatives of rice be used to improve Oryza sativa?

    Science.gov (United States)

    Atwell, Brian J; Wang, Han; Scafaro, Andrew P

    2014-02-01

    Oryza sativa and Oryza glaberrima have been selected to acquire and partition resources efficiently as part of the process of domestication. However, genetic diversity in cultivated rice is limited compared to wild Oryza species, in spite of 120,000 genotypes being held in gene banks. By contrast, there is untapped diversity in the more than 20 wild species of Oryza, some having been collected from just a few coastal locations (e.g. Oryza schlechteri), while others are widely distributed (e.g. Oryza nivara and Oryza rufipogon). The extent of DNA sequence diversity and phenotypic variation is still being established in wild Oryza, with genetic barriers suggesting a vast range of morphologies and function even within species, such as has been demonstrated for Oryza meridionalis. With increasing climate variability and attempts to make more marginal land arable, abiotic and biotic stresses will be managed over the coming decades by tapping into the genetic diversity of wild relatives of O. sativa. To help create a more targeted approach to sourcing wild rice germplasm for abiotic stress tolerance, we have created a climate distribution map by plotting the natural occurrence of all Oryza species against corresponding temperature and moisture data. We then discuss interspecific variation in phenotype and its significance for rice, followed by a discussion of ways to integrate germplasm from wild relatives into domesticated rice. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Effects of gamma irradiation on long-storage seeds of Oryza sativa (cv. 2233) and their surface infecting fungal diversity

    International Nuclear Information System (INIS)

    Maity, J.P.; Kar, S.; Banerjee, S.; Chakraborty, A.; Santra, S.C.

    2009-01-01

    We have reported an effective 60 Co gamma irradiation method for the removal and long-time prevention of contaminating fungi of Oryza sativa cv-2233, without the losses of seed viabilities. The fungal growth and their population on gamma treated seeds was found to decrease significantly (p 50%) at 2 kGy, whereas total inhibition was noticed at 3 kGy after 1.5 month.

  1. Genetic analysis and gene fine mapping of aroma in rice (Oryza sativa L. Cyperales, Poaceae

    Directory of Open Access Journals (Sweden)

    Shu Xia Sun

    2008-01-01

    Full Text Available We investigated inheritance and carried out gene fine mapping of aroma in crosses between the aromatic elite hybrid rice Oryza sativa indica variety Chuanxiang-29B (Ch-29B and the non-aromatic rice O. sativa indica variety R2 and O. sativa japonica Lemont (Le. The F1 grains and leaves were non-aromatic while the F2 non-aroma to aroma segregation pattern was 3:1. The F3 segregation ratio was consistent with the expected 1:2:1 for a single recessive aroma gene in Ch-29B. Linkage analysis between simple sequence repeat (SSR markers and the aroma locus for the aromatic F2 plants mapped the Ch-29B aroma gene to a chromosome 8 region flanked by SSR markers RM23120 at 0.52 cM and RM3459 at 1.23 cM, a replicate F2 population confirming these results. Three bacterial artificial chromosome (BAC clones cover chromosome 8 markers RM23120 and RM3459. Our molecular mapping data from the two populations indicated that the aroma locus occurs in a 142.85 kb interval on BAC clones AP005301 or AP005537, implying that it might be the same gene reported by Bradbury et al (2005a; Plant Biotec J. 3:363-370. The flanking markers Aro7, RM23120 and RM3459 identified by us could greatly accelerate the efficiency and precision of aromatic rice breeding programs.

  2. A Hypersensitivity-Like Response to Meloidogyne graminicola in Rice (Oryza sativa).

    Science.gov (United States)

    Phan, Ngan Thi; De Waele, Dirk; Lorieux, Mathias; Xiong, Lizhong; Bellafiore, Stephane

    2018-04-01

    Meloidogyne graminicola is a major plant-parasitic nematode affecting rice cultivation in Asia. Resistance to this nematode was found in the African rice genotypes Oryza glaberrima and O. longistaminata; however, due to interspecific hybrid sterility, the introgression of resistance genes in the widely consumed O. sativa varieties remains challenging. Recently, resistance was found in O. sativa and, here, we report for the first time the histological and genetic characterization of the resistance to M. graminicola in Zhonghua 11, an O. sativa variety. Bright-light microscopy and fluorescence observations of the root tissue of this variety revealed that the root cells surrounding the nematode displayed a hypersensitivity-like reaction with necrotic cells at early stages of infection when nematodes are migrating in the root's mesoderm. An accumulation of presumably phenolic compounds in the nematodes' neighboring root cells was also observed. In addition, at a later stage of infection, not only were few feeding sites observed but also the giant cells were underdeveloped, underlining an incompatible interaction. Furthermore, we generated a hybrid O. sativa population by crossing Zhonghua 11 with the susceptible O. sativa variety IR64 in order to describe the genetic background of this resistance. Our data suggested that the resistance to M. graminicola infection was qualitative rather than quantitative and, therefore, major resistance genes must be involved in this infection process. The full characterization of the defense mechanism and the preliminary study of the genetic inheritance of novel sources of resistance to Meloidogyne spp. in rice constitute a major step toward their use in crop breeding.

  3. Systematic analysis of rice (Oryza sativa) metabolic responses to herbivory.

    Science.gov (United States)

    Alamgir, Kabir Md; Hojo, Yuko; Christeller, John T; Fukumoto, Kaori; Isshiki, Ryutaro; Shinya, Tomonori; Baldwin, Ian T; Galis, Ivan

    2016-02-01

    Plants defend against attack from herbivores by direct and indirect defence mechanisms mediated by the accumulation of phytoalexins and release of volatile signals, respectively. While the defensive arsenals of some plants, such as tobacco and Arabidopsis are well known, most of rice's (Oryza sativa) defence metabolites and their effectiveness against herbivores remain uncharacterized. Here, we used a non-biassed metabolomics approach to identify many novel herbivory-regulated metabolic signatures in rice. Most were up-regulated by herbivore attack while only a few were suppressed. Two of the most prominent up-regulated signatures were characterized as phenolamides (PAs), p-coumaroylputrescine and feruloylputrescine. PAs accumulated in response to attack by both chewing insects, i.e. feeding of the lawn armyworm (Spodoptera mauritia) and the rice skipper (Parnara guttata) larvae, and the attack of the sucking insect, the brown planthopper (Nilaparvata lugens, BPH). In bioassays, BPH insects feeding on 15% sugar solution containing p-coumaroylputrescine or feruloylputrescine, at concentrations similar to those elicited by heavy BPH attack in rice, had a higher mortality compared to those feeding on sugar diet alone. Our results highlight PAs as a rapidly expanding new group of plant defence metabolites that are elicited by herbivore attack, and deter herbivores in rice and other plants. © 2015 John Wiley & Sons Ltd.

  4. Fe deficiency induced changes in rice (Oryza sativa L.) thylakoids.

    Science.gov (United States)

    Wang, Yuwen; Xu, Chao; Li, Kang; Cai, Xiaojie; Wu, Min; Chen, Guoxiang

    2017-01-01

    Iron deficiency is an important abiotic stress that limits productivity of crops all over the world. We selected a hybrid rice (Oryza sativa L.), LYPJ, which is super high-yield and widely cultured in China, to investigate changes in the components and structure of thylakoid membranes and photosynthetic performance in response to iron deficiency. Our results demonstrated that photosystem I (PSI) is the primary target for iron deficiency, while the changes in photosystem II (PSII) are important for rebuilding a balance in disrupted energy utilization and dissipation caused by differential degradation of photosynthetic components. The result of immunoblot analysis suggested that the core subunit PsaA declined drastically, while PsbA remained relatively stable. Furthermore, several organizational changes of the photosynthetic apparatus were found by BN-PAGE, including a marked decrease in the PSI core complexes, the Cytb 6 /f complex, and the trimeric form of the LHCII antenna, consistent with the observed unstacking grana. The fluorescence induction analysis indicated a descending PSII activity with energy dissipation enhanced markedly. In addition, we proposed that the crippled CO 2 assimilation could be compensated by the enhanced of phosphoenolpyruvate carboxylase (PEPC), which is suggested by the decreased ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and photosynthetic efficiency.

  5. Pemanfaatan Ekstrak Tanaman Ketan Hitam (Oryza Sativa Glutinosa) sebagai Indikator Asam Basa

    OpenAIRE

    Hasibuan, Muhammad Arief; Amran, Elva Yasmi; ', Susilawati

    2016-01-01

    Research was conducted with the aims to determine pH range, percentage acid base indicator titration error, and stability of Oryza sativa Glutinosa extract as acid base indicator. Oryza sativa Glutinosa grains respectively extracted with maseration using ethanol (HCl 1%). pH range determined by added the extract into buffer solutions pH 1-9. Percentage acid base indicator titration error determined by applied the extract in strong acid-strong base, weak acid-strong base, strong acid-weak base...

  6. Desempenho de populações híbridas F2 de arroz-vermelho (Oryza sativa com arroz transgênico (O. sativa resistente ao herbicida amonio-glufosinate Performance of F2 hybrid populations of red rice (Oryza sativa with ammonium-glufosinate-resistant transgenic rice (O. sativa

    Directory of Open Access Journals (Sweden)

    J.A. Noldin

    2004-09-01

    -preto. Mesmo assim, os usuários dessa tecnologia deverão adotar, obrigatoriamente, medidas que evitem a possibilidade de cruzamento entre o arroz transgênico e o arroz-vermelho ou arroz-preto.Red rice is an important weed in paddy rice fields. The use of ammonium glufosinate - resistant genetically modified (GM rice cultivars is a viable alternative for controlling red rice in cultivated rice crops. The objective of this study was to evaluate the behavior of F2 hybrid population derivates of crossing between ammonium glufosinate - resistant GM rice and red rice. The F2 hybrid population derivates of crossing between GM rice and red rice are viable but do not present any apparent competitive advantage over red rice. The morphological characteristics of the F2 hybrid populations, such as tillering capacity, number of leaves produced and average plant height were partly reduced and partly unaffected by the introgression of the bar gene. The period between rice planting and 50% flowering increased in the red rice x GM rice F2 hybrids, compared to the parental red rice and GM rice. Average seed shattering rate in the four hybrid families was lower than in the red rice ecotypes, with such aspect also being unfavorable to the persistence of red rice in the environment. Seed dormancy of the hybrids was similar to that of the red rice ecotypes. However, management practices should be adopted to avoid crossing between transgenic rice and red rice.

  7. Detection of Alien Oryza punctata Kotschy Chromosomes in Rice, Oryza sativa L., by Genomic in situ Hybridization

    OpenAIRE

    Yasui, Hideshi; Nonomura, Ken-ichi; Iwata, Nobuo; 安井, 秀; 野々村, 賢一; 岩田, 伸夫

    1997-01-01

    Genomic in situ hybridization (GIS H) using total Oryza punctata Kotschy genomic DNA as a probe was applied to detect alien chromosomes transferred from O. punctata (W1514: 2n=2x=24: BB) to O. sativa Japonica cultivar, Nipponbare (2n=2x=24: AA). Only 12 chromosomes in the interspecific hybrids (2n=3x=36: AAB) between autotetraploid of O. sativa cultivar Nipponbare and a diploid strain of O. punctata (W1514) showed intense staining by FITC in mitotic metaphase spreads. Only one homologous pair...

  8. Bekatul (Oryza sativa L. Menghambat Peningkatan Kadar Kolesterol Darah

    Directory of Open Access Journals (Sweden)

    Astri Kania

    2014-02-01

    Full Text Available Abstrak Penyakit kardiovaskuler merupakan penyebab utama kematian dan kecacatan di seluruh dunia, termasuk Indonesia. Penyakit kardiovaskuler disebabkan oleh pembentukan aterosklerosis pada pembuluh darah. Konsumsi larutan tepung bekatul (Oryza sativa L. dapat digunakan sebagai salah satu upaya untuk mencegah terjadinya aterosklerosis dengan cara menghambat peningkatan kadar kolesterol darah. Penelitian ini untuk menilai efek larutan tepung bejatul terhadap penghambatan peningkatan kadar kolesterol darah. Penelitian eksperimental laboratorik dengan rancangan acak lengkap telah dilakukan pada 20 ekor tikus putih jantan galur Wistar yang dibagi menjadi lima kelompok. Kelompok I adalah kontrol negatif yang diberikan diet tinggi lemak dan propiltiurasil (PTU 0,01%, kelompok II merupakan kontrol positif yang hanya diberi pelet. Kelompok III, IV, dan V adalah kelompok perlakuan yang diberikan sediaan uji 0,27 gram/200 gram BB, 0,54 gram/200 gram BB, dan 1,08 gram/200 gram BB, DTL dan PTU 0,01% secara bersamaan. Pengukuran kadar kolesterol darah dilakukan sebelum diberikan perlakuan (hari ke-7 dan setelah diberikan perlakuan (hari ke-21 dengan menggunakan metode kolorimetrik enzimatik. Hasil penelitian ini menunjukkan bahwa larutan tepung bekatul memiliki efek penghambatan terhadap peningkatan kadar kolesterol darah dengan dosis 0,54 gram/200 gram BB. Efek penghambatan tersebut diakibatkan oleh mekanisme interaksi  dari orizanol, fitosterol, dan omega-3 yang terdapat dalam larutan tepung bekatul. Kata kunci: Bekatul, efek penghambatan, kolesterol darah   Rice Bran (Oryza sativa L. Inhibit the Increase of Blood Cholesterol Level Abstract Cardiovascular disease is the major cause of mortality and morbidity in the world, including Indonesia. This disease caused by atherosclerosis formation in blood vessel. Consumption of rice bran is one alternative to prevent atherosclerosis by inhibiting the increase of blood cholesterol level. The Aim of study was to

  9. Effect of atmospheric plasma treatment on seed germination of rice (Oryza sativa L.)

    Science.gov (United States)

    Penado, Keith Nealson M.; Mahinay, Christian Lorenz S.; Culaba, Ivan B.

    2018-01-01

    Multiple methods of improving plant development have been utilized over the past decades. Despite these improvements, there still exists a need for better planting methods due to the increasing population of a global community. Studies have reported that plasma treatment affects the growth and germination of a variety of plant species, including a multitude of grains which often takes the bulk in the diet of the average human being. This study explores the effect of atmospheric air plasma jet treatment on the seed germination of rice (Oryza sativa L.). The seeds were treated using an atmospheric air plasma jet for 1, 2, and 3 s. The effect of plasma exposure shows a reduction of trichomes on the surface of the seed. This caused a possible increase in wettability which significantly affected the seed germ length but did not affect the seed germination count after the germination period of 72 h.

  10. Rice is the seed of the monocot plants Oryza sativa (Asian rice) or ...

    African Journals Online (AJOL)

    BIOTECH

    2013-10-16

    Oct 16, 2013 ... of culture. The regenerated plantlets were transferred to pots for acclimatization. About 80% of plants were survived in the greenhouse condition. Key words: Somatic embryogenesis, immature zygotic embryos, Indica rice, plant regeneration. INTRODUCTION. Rice (Oryza sativa L.) is one of the most ...

  11. Can rice (Oryza sativa) mitigate pesticides and nutrients in agricultural runoff?

    Science.gov (United States)

    Phytoremediation of nutrients and pesticides in runoff is a growing conservation effort, particularly in agriculturally intensive areas such as the lower Mississippi River Valley. In the current study, rice (Oryza sativa) was examined for its mitigation capacity of nitrogen, phosphorus, diazinon, a...

  12. Growth responses of NaCl stressed rice (Oryza sativa L.) plants ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-27

    Sep 27, 2010 ... Growth responses of NaCl stressed rice (Oryza sativa. L.) plants ... 2008), which is a real threat to human's food security. Existed situation may ..... content and composition of essential oil and minerals in black cumin. (Nigella ...

  13. Analysis of the temporal variation of radiation balance components in arid rice (Oryza sativa L.) culture

    International Nuclear Information System (INIS)

    Prates, J.E.; Coelho, D.T.; Steinmetz, S.

    1988-01-01

    The time variation of measured radiation balance components in a cultived rice area (Oryza sativa L.) under arid conditions in the Brazil central-west region was analysed. The relation between global solar radiation, radiation balance, reflected radiation and terrestrial effective radiation in three different stages of the culture development: vegetative stage; blooming and maturation, was determined. (M.C.K.) [pt

  14. An ecogeographic analysis of Oryza series Sativae in Asia and the Pacific

    NARCIS (Netherlands)

    Banaticla-Hilario, M.C.N.

    2012-01-01

    The non-cultivated speciesof the genus Oryza can provide a genetic arsenal of useful traits for improving the widely cultivated and consumed Asian rice (O. sativa). The diversity of these valuable plant resources must be well understood to ensure their effective in- and ex-situ

  15. Assessment of genomic relationship between Oryza sativa and ...

    African Journals Online (AJOL)

    The hybrid was produced between these two species at the International Rice Research Institute using embryo rescue technique. The chromosome pairing was examined in pollen mother cells of O. australinesis, O. sativa and the hybrid between O. sativa and O. australinesis. The hybrid was highly sterile with pollen stain ...

  16. Genome-wide association mapping for yield and other agronomic traits in an elite breeding population of tropical rice (Oryza sativa).

    Science.gov (United States)

    Begum, Hasina; Spindel, Jennifer E; Lalusin, Antonio; Borromeo, Teresita; Gregorio, Glenn; Hernandez, Jose; Virk, Parminder; Collard, Bertrand; McCouch, Susan R

    2015-01-01

    Genome-wide association mapping studies (GWAS) are frequently used to detect QTL in diverse collections of crop germplasm, based on historic recombination events and linkage disequilibrium across the genome. Generally, diversity panels genotyped with high density SNP panels are utilized in order to assay a wide range of alleles and haplotypes and to monitor recombination breakpoints across the genome. By contrast, GWAS have not generally been performed in breeding populations. In this study we performed association mapping for 19 agronomic traits including yield and yield components in a breeding population of elite irrigated tropical rice breeding lines so that the results would be more directly applicable to breeding than those from a diversity panel. The population was genotyped with 71,710 SNPs using genotyping-by-sequencing (GBS), and GWAS performed with the explicit goal of expediting selection in the breeding program. Using this breeding panel we identified 52 QTL for 11 agronomic traits, including large effect QTLs for flowering time and grain length/grain width/grain-length-breadth ratio. We also identified haplotypes that can be used to select plants in our population for short stature (plant height), early flowering time, and high yield, and thus demonstrate the utility of association mapping in breeding populations for informing breeding decisions. We conclude by exploring how the newly identified significant SNPs and insights into the genetic architecture of these quantitative traits can be leveraged to build genomic-assisted selection models.

  17. Open Access Resources for Genome Wide Association Studies (GWAS) in rice (Oryza sativa) illustrate the power of population-specific mapping

    Science.gov (United States)

    Increasing food production is essential to meet the demands of a growing human population, with its rising income levels and nutritional expectations. New sources of genetic variation are key to enhancing the productivity, sustainability and resilience of crop varieties and agricultural systems that...

  18. Methodical characterization of rice ( Oryza sativa bran oil from Pakistan

    Directory of Open Access Journals (Sweden)

    Mahmood, Zahid

    2005-06-01

    Full Text Available The hexane-extracted oil content of four varieties of rice (Oryza sativa viz. Super Kernel, 386, 385 and Basmati, bran was ranged 14.70-19.10 %. Other physical and chemical parameters of the extracted oils were as follow: Iodine value 112.40, 109.80, 105.1 and 103.70; refractive index ( 40 °C 1.4650, 1.4680, 1.4657 and 1.4660; density ( 40 °C 0.919, 0.913, 0.909 and 0.911; saponification value 183, 177, 186 and 190; unsaponifiable matter 6.15, 5.60, 4.98 and 5.40 % respectively. Tocopherols ( α, γ and δ in the oils were: 284.00, 175.12, 180.42, 300.06; 83.40, 98.70, 120.70, 90.60; 75.16, 57.20, 39.32, 83.00 mg/kg respectively. The contents of tocotrienols ( α, γ and δ in the oils were: 120.30, 106.00, 95.20, 135.74; 196.00, 125.00, 210.0, 276.41; 72.50, 20.00, 39.30, 64.00 mg/kg respectively. The amount of γ - Oryzanol in the investigated oils was ranged 415.12-802.05 The induction periods (Rancimat, 20 L/h, 120 °C of the crude oils were 6.81, 5.99, 6.39 and 7.40 h respectively. The major sterol fractions of the oils consisted of campesterol ranged (10.10-19.20%, stigmasterol (14.00-19.28 %, b -sitosterol (49.30-58.20 %, and D5 ,avenasterol (8.14-13.05 %. The investigated varieties ( Super Kernel, 386, 385 and Basmati of rice bran oil were found to contain high levels of oleic acid 42.67, 38.59, 40.68 and 36.78 % followed by linoleic and palmitic acids 31.58, 33.80, 28.70, 30.51 and 17.00, 14.88, 19.63, 20.00 % respectively. The contents of myristic, stearic and arachidic acids was 1.50, 2.02, 4.28, 1.00; 2.64, 2.87, 4.02, 7.48; and 1.28, 3.00, 1.00, 1.00 % respectively. A number of parameters of the investigated rice bran oils indigenous to Pakistan were comparable to those of typical rice bran and some other vegetable oils, reported in the literature. The results of the present analysis as compared with those of different vegetable oils demonstrated rice bran to be a potential oil source and thus could be useful

  19. Population Structure, Diversity and Trait Association Analysis in Rice (Oryza sativa L. Germplasm for Early Seedling Vigor (ESV Using Trait Linked SSR Markers.

    Directory of Open Access Journals (Sweden)

    Annamalai Anandan

    Full Text Available Early seedling vigor (ESV is the essential trait for direct seeded rice to dominate and smother the weed growth. In this regard, 629 rice genotypes were studied for their morphological and physiological responses in the field under direct seeded aerobic situation on 14th, 28th and 56th days after sowing (DAS. It was determined that the early observations taken on 14th and 28th DAS were reliable estimators to study ESV as compared to 56th DAS. Further, 96 were selected from 629 genotypes by principal component (PCA and discriminate function analyses. The selected genotypes were subjected to decipher the pattern of genetic diversity in terms of both phenotypic and genotypic by using ESV QTL linked simple sequence repeat (SSR markers. To assess the genetic structure, model and distance based approaches were used. Genotyping of 96 rice lines using 39 polymorphic SSRs produced a total of 128 alleles with the phenotypic information content (PIC value of 0.24. The model based population structure approach grouped the accession into two distinct populations, whereas unrooted tree grouped the genotypes into three clusters. Both model based and structure based approach had clearly distinguished the early vigor genotypes from non-early vigor genotypes. Association analysis revealed that 16 and 10 SSRs showed significant association with ESV traits by general linear model (GLM and mixed linear model (MLM approaches respectively. Marker alleles on chromosome 2 were associated with shoot dry weight on 28 DAS, vigor index on 14 and 28 DAS. Improvement in the rate of seedling growth will be useful for identifying rice genotypes acquiescent to direct seeded conditions through marker-assisted selection.

  20. Tanggap Pertumbuhan dan Produksi Padi (Oryza sativa L.) Varietas Ciherang Terhadap Pemberian Pupuk Organik

    OpenAIRE

    Sari, Vira Irma

    2011-01-01

    VIRA IRMA SARI. Response of Growth and Production of Rice (Oryza sativa L.) Variety Ciherang to The Application of Organic Fertilizer. Scarcity of inorganic fertilizer and the negative effect caused by inorganic fertilizer continuing to make organic fertilizer as a solution to overcome these problems. The availability of organic fertilizers is expected that the farmers can get the optimal production and profit, because the organic fertilizer is cheaper and easy ...

  1. Genetic analysis of yield and yield components in Oryza sativa x ...

    African Journals Online (AJOL)

    ... inheritance of yield and yield components and to estimate the heritabilities of important quantitative traits in rice (Oryza sativa L.). Six generations viz., P1, P2, F1, F2, BCP1 and BCP2 of a cross between IET6279 and IR70445-146-3-3 were used for the study. Generation mean analysis suggested that additive effects had a ...

  2. Differences in the Sensitivity to UVB Radiation of Two Cultivars of Rice (Oryza sativa L.)

    OpenAIRE

    Jun, Hidema; Hye-Sook, Kang; Tadashi, Kumagai; Institute of Genetic Ecology, Tohoku University; Institute of Genetic Ecology, Tohoku University; Institute of Genetic Ecology, Tohoku University

    1996-01-01

    The effects of UVB radiation on the growth of two cultivars of Japanese lowland rice (Oryza sativa L.), Sasanishiki and Norin 1, were examined in a phytotron. Supplementation of visible radiation with UVB radiation reduced plant length, tiller number, the fresh and dry weights of the aboveground parts of plants, and the amounts of total leaf nitrogen, chlorophyll, soluble protein and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) in the eighth leaf, the youngest fully expanded leaf...

  3. Fine mapping of S37, a locus responsible for pollen and embryo sac sterility in hybrids between Oryza sativa L. and O. glaberrima Steud.

    Science.gov (United States)

    Shen, Yumin; Zhao, Zhigang; Ma, Hongyang; Bian, Xiaofeng; Yu, Yang; Yu, Xiaowen; Chen, Haiyuan; Liu, Linglong; Zhang, Wenwei; Jiang, Ling; Zhou, Jiawu; Tao, Dayun; Wan, Jianmin

    2015-11-01

    Hybrid sterility locus S37 between Oryza glaberrima and Oryza sativa results in both pollen and embryo sac sterility. Interspecific crossing between African cultivated rice Oryza glaberrima and Oryza sativa cultivars is hindered by hybrid sterility. To dissect the mechanism of interspecific hybrid sterility, we developed a near-isogenic line (NIL)-S37 using Dianjingyou1 (DJY1) as the recipient parent and an African cultivated rice variety as the donor parent. Empty pollen and embryo sac sterility were observed in F1 hybrids between DJY1 and NIL-S37. Cytological analyses showed that pollen abortion in the F1 hybrids occurred at the late binucleate stage due to a failure of starch accumulation in pollen grains. In addition, partial abortion of the embryo sac in the F1 hybrid was observed during function megaspore developing into mature embryo sac. Molecular analysis revealed that the semi-sterility was largely caused by the abortion of male and female gametophytes carrying the S37 allele from DJY1. A population of 25,600 plants derived from the hybrid DJY1/NIL-S37 was developed to fine map S37. Based on the physical location of molecular markers, S37 locus was finally delimited to a region of 205 kb on the short arm of chromosome 1 in terms of reference sequences of cv. Nipponbare. Interestingly, an about 97-kb DNA segment was deleted in the NIL-S37 based on BAC clone information of O. glaberrima. Fifty-four open reading frames (ORF) were predicted in this 205-kb region of DJY1, whereas only 31 ORFs were in that of NIL-S37. These results are valuable for cloning of S37 gene and further breaking reproductive isolation between Oryza glaberrima and Oryza sativa cultivars, as well as marker-assisted transferring of the corresponding neutral allele in rice breeding programs.

  4. Origin of Oryza sativa in China inferred by nucleotide polymorphisms of organelle DNA.

    Directory of Open Access Journals (Sweden)

    Xin Wei

    Full Text Available China is rich of germplasm resources of common wild rice (Oryza rufipogon Griff. and Asian cultivated rice (O. sativa L. which consists of two subspecies, indica and japonica. Previous studies have shown that China is one of the domestication centers of O. sativa. However, the geographic origin and the domestication times of O. sativa in China are still under debate. To settle these disputes, six chloroplast loci and four mitochondrial loci were selected to examine the relationships between 50 accessions of Asian cultivated rice and 119 accessions of common wild rice from China based on DNA sequence analysis in the present study. The results indicated that Southern China is the genetic diversity center of O. rufipogon and it might be the primary domestication region of O. sativa. Molecular dating suggested that the two subspecies had diverged 0.1 million years ago, much earlier than the beginning of rice domestication. Genetic differentiations and phylogeography analyses indicated that indica was domesticated from tropical O. rufipogon while japonica was domesticated from O. rufipogon which located in higher latitude. These results provided molecular evidences for the hypotheses of (i Southern China is the origin center of O. sativa in China and (ii the two subspecies of O. sativa were domesticated multiple times.

  5. Quantitative phosphoproteomic analysis of early seed development in rice (Oryza sativa L.).

    Science.gov (United States)

    Qiu, Jiehua; Hou, Yuxuan; Tong, Xiaohong; Wang, Yifeng; Lin, Haiyan; Liu, Qing; Zhang, Wen; Li, Zhiyong; Nallamilli, Babi R; Zhang, Jian

    2016-02-01

    Rice (Oryza sativa L.) seed serves as a major food source for over half of the global population. Though it has been long recognized that phosphorylation plays an essential role in rice seed development, the phosphorylation events and dynamics in this process remain largely unknown so far. Here, we report the first large scale identification of rice seed phosphoproteins and phosphosites by using a quantitative phosphoproteomic approach. Thorough proteomic studies in pistils and seeds at 3, 7 days after pollination resulted in the successful identification of 3885, 4313 and 4135 phosphopeptides respectively. A total of 2487 proteins were differentially phosphorylated among the three stages, including Kip related protein 1, Rice basic leucine zipper factor 1, Rice prolamin box binding factor and numerous other master regulators of rice seed development. Moreover, differentially phosphorylated proteins may be extensively involved in the biosynthesis and signaling pathways of phytohormones such as auxin, gibberellin, abscisic acid and brassinosteroid. Our results strongly indicated that protein phosphorylation is a key mechanism regulating cell proliferation and enlargement, phytohormone biosynthesis and signaling, grain filling and grain quality during rice seed development. Overall, the current study enhanced our understanding of the rice phosphoproteome and shed novel insight into the regulatory mechanism of rice seed development.

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

    Science.gov (United States)

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

    2017-07-01

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

  7. Variations in characters of diploid-like plants derived from gamma-irradiated tetraploids in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Yamamoto, K.; Fukuoka, H.; Kageyama, Y.; Takeda, G.

    1990-01-01

    Full text: Populations of artificial autotetraploids of rice (Oryza sativa L. cvs. 'Nipponbare' and 'Fukunishiki') were repeatedly irradiated with gamma-rays through several generations. Plants which did not differ in appearance from the original diploid plants occurred occasionally in the populations. Nine diploid-like plants were obtained so far, and their generations were advanced without irradiation in order to examine the mode of segregation of characters in their progeny. The results indicate that diploid-like plants with multiple mutant characters could be obtained and that dominant characters, i.e. awned spikelet and coloured apiculus, were included in the mutant characters. The diploid-like plants had 2n=24 chromosomes. (author)

  8. Robustness and Strategies of Adaptation among Farmer Varieties of African Rice (Oryza glaberrima) and Asian Rice (Oryza sativa) across West Africa

    NARCIS (Netherlands)

    Mokuwa, A.; Nuijten, H.A.C.P.; Okry, F.; Teeken, B.W.E.; Maat, H.; Richards, P.; Struik, P.C.

    2013-01-01

    This study offers evidence of the robustness of farmer rice varieties (Oryza glaberrima and O. sativa) in West Africa. Our experiments in five West African countries showed that farmer varieties were tolerant of sub-optimal conditions, but employed a range of strategies to cope with stress.

  9. Genetic study of resistance to inhibitory effects of UV radiation in rice (Oryza sativa)

    International Nuclear Information System (INIS)

    Sato, T.; Kang, H.S.; Kumagai, T.

    1994-01-01

    Genetic analysis of resistance to the inhibitory effects of UV radiation on growth of rice (Oryza sativa L.) cultivars was carried out. Some experimental plants were grown in visible radiation supplemented with UV radiation containing a large amount of UV-B and a small amount of UV-C in a phytotron, while others were grown without UV radiation. The degree of resistance to UV radiation was estimated in terms of the degree of reduction caused by supplemental UV radiation in the fresh weight of the aboveground plant parts and the chlorophyll content per unit fresh weight. Fresh weight and chlorophyll content in F 2 plants generated by reciprocally crossing cv. Sasanishiki, a cultivar more resistant to UV radiation, and Norin 1, a cultivar less resistant to such radiation exhibited a normal frequency distribution. The heritabilities of these two properties in F 2 plants were low under conditions of non-supplemental UV radiation. Under elevated UV radiation, the F 2 population shifted to the lower range of fresh weight and chlorophyll content, and the means were close to those of Norin 1. The heritabilities of these two properties were the same in the reciprocal crosses, indicating that maternal inheritance was not involved. Inheritance of chlorophyll content per unit fresh weight was further determined in F 3 lines generated by self-fertilizing F 2 plants of Sasanishiki and Norin 1. The results showed that the F 3 population was segregated into three genotypes, namely, resistant homozygotes, segregated heterozygotes and sensitive homozygotes, with a ratio of 1:65:16. It was thus evident that the resistance to the inhibitory effect of elevated UV radiation in these rice plants was controlled by recessive polygenes. (author)

  10. Vinegar rice (Oryza sativa L.) produced by a submerged fermentation process from alcoholic fermented rice

    OpenAIRE

    Spinosa,Wilma Aparecida; Santos Júnior,Vitório dos; Galvan,Diego; Fiorio,Jhonatan Luiz; Gomez,Raul Jorge Hernan Castro

    2015-01-01

    Considering the limited availability of technology for the production of rice vinegar and also due to the potential consumer product market, this study aimed to use alcoholic fermented rice (rice wine (Oryza sativa L.)) for vinegar production. An alcoholic solution with 6.28% (w/v) ethanol was oxidized by a submerged fermentation process to produce vinegar. The process of acetic acid fermentation occurred at 30 ± 0.3°C in a FRINGS® Acetator (Germany) for the production of vineg...

  11. Formulasi Sediaan Lipstik Menggunakan Ekstrak Beras Ketan Hitam (Oryza sativa L var forma glutinosa) Sebagai Pewarna

    OpenAIRE

    Utami, Rini

    2011-01-01

    Black sticky rice (Oryza sativa L.) belongs to Poaceae family which is used by people as food stuffs such as tape and porridge. Black sticky rice is red/purple and its dye stuff is strong enough. In cosmetic, dye stuff is one of the causes of irritation and allergy on skin so that the researcher has made the formulation of lipstick component using natural dye stuff made of black sticky rice. The formulation of lipstick component consisted of some components such as cera alba, lanolin,...

  12. Molecular characterization and genetic diversity of different genotypes of Oryza sativa and Oryza glaberrima

    Directory of Open Access Journals (Sweden)

    Caijin Chen

    2017-11-01

    Conclusions: Genetic diversity studies revealed that 50 rice types were clustered into different subpopulations whereas three genotypes were admixtures. Molecular fingerprinting and 10 specific markers were obtained to identify the 53 rice genotypes. These results can facilitate the potential utilization of sibling species in rice breeding and molecular classification of O. sativa and O. glaberrima germplasms.

  13. ALOGAMIA EM ARROZ (Oryza sativa L. E RELAÇÃO COM CARACTERÍSTICAS AGRONÔMICAS RICE (Oryza sativa L. ALLOGAMY AND RELATIONSHIP WITH AGRONOMIC TRAITS

    Directory of Open Access Journals (Sweden)

    Péricles de Carvalho Ferreira Neves

    2007-09-01

    Full Text Available

    A produção de sementes híbridas de arroz, utilizando a técnica chinesa, requer uma grande quantidade de mão-de-obra e é cara. Alternativas para aumentar a taxa de polinização cruzada podem ajudar a reduzir tal custo. A Embrapa Arroz e Feijão desenvolve um projeto de produção de híbridos através da transferência de caracteres alogâmicos (comprimento de estigma e antera da Oryza longistaminata A. Chev. para a cultivada Oryza sativa L. O objetivo deste estudo foi determinar as correlações genética e fenotípica entre esses caracteres e os agronômicos. O. longistaminata foi cruzada com a O. sativa e retrocruzada duas vezes para a cultivada. Foram obtidas 25 linhagens F3:6 e estudadas as correlações entre os caracteres alogâmicos (comprimento de estigma, antera e espigueta e os agronômicos (comprimento de estigma, antera, espigueta, arista e panícula, esterilidade, degrane, altura de planta, perfilhos por planta, e exserção de panícula. O desenho experimental utilizado foi o de blocos ao acaso com quatro repetições. Os ensaios foram conduzidos em dois locais dentro da área experimental da Embrapa Arroz e Feijão. Em geral, foram observadas pequenas correlações genética e fenotípica entre caracteres alogâmicos e agronômicos. Elevada e significativa associação foi observada entre o comprimento de estigma e o de anteras, o comprimento de estigma e o de arista, o comprimento de antera e o de arista, e o comprimento de panícula e a altura de planta.

    PALAVRAS-CHAVE: Oryza longistaminata; taxa de autopolinização; arroz híbrido; produção de sementes.

  14. Association analysis of three diverse rice (Oryza sativa L.) germplasm collections for loci regulating grain quality traits

    Science.gov (United States)

    In rice (Oryza sativa L.), end-use/cooking quality is vital for producers and millions of consumers worldwide. Grain quality is a complex trait with interacting genetic and environmental factors. Deciphering the complex genetic architecture associated with grain quality, will provide vital informati...

  15. X-ray diffraction analysis and in vitro characterization of the UAM2 protein from Oryza sativa

    DEFF Research Database (Denmark)

    Welner, Ditte Hededam; Tsai, Alex Yi-Lin; DeGiovanni, Andy M.

    2017-01-01

    protein from Oryza sativa (OsUAM2) were undertaken. Here, X-ray diffraction data are reported, as well as analysis of the oligomeric state in the crystal and in solution. OsUAM2 crystallizes readily but forms highly radiation-sensitive crystals with limited diffraction power, requiring careful low......, a requirement for a structural metal ion....

  16. Association analysis using USDA diverse rice (Oryza sativa L.) germplasm collections to identify loci influencing grain quality traits

    Science.gov (United States)

    he USDA rice (Oryza sativa L.) core subset (RCS) was assembled to represent the genetic diversity of the entire USDA-ARS National Small Grains Collection and consists of 1,794 accessions from 114 countries. The USDA rice mini-core (MC) is a subset of 217 accessions from the RCS and was selected to ...

  17. Genetic Architecture of Cold Tolerance in Rice (Oryza sativa) Determined through High Resolution Genome-Wide Analysis

    Science.gov (United States)

    Cold temperature is an important abiotic stress which negatively affects morphological development and seed production in rice (Oryza sativa L.). At the seedling stage, cold stress causes poor germination, seedling injury and poor stand establishment; and at the reproductive stage cold decreases se...

  18. Robustness and strategies of adaptation among farmer varieties of African Rice (Oryza glaberrima) and Asian Rice (Oryza sativa) across West Africa.

    Science.gov (United States)

    Mokuwa, Alfred; Nuijten, Edwin; Okry, Florent; Teeken, Béla; Maat, Harro; Richards, Paul; Struik, Paul C

    2013-01-01

    This study offers evidence of the robustness of farmer rice varieties (Oryza glaberrima and O. sativa) in West Africa. Our experiments in five West African countries showed that farmer varieties were tolerant of sub-optimal conditions, but employed a range of strategies to cope with stress. Varieties belonging to the species Oryza glaberrima - solely the product of farmer agency - were the most successful in adapting to a range of adverse conditions. Some of the farmer selections from within the indica and japonica subspecies of O. sativa also performed well in a range of conditions, but other farmer selections from within these two subspecies were mainly limited to more specific niches. The results contradict the rather common belief that farmer varieties are only of local value. Farmer varieties should be considered by breeding programmes and used (alongside improved varieties) in dissemination projects for rural food security.

  19. Robustness and Strategies of Adaptation among Farmer Varieties of African Rice (Oryza glaberrima) and Asian Rice (Oryza sativa) across West Africa

    Science.gov (United States)

    Maat, Harro; Richards, Paul; Struik, Paul C.

    2013-01-01

    This study offers evidence of the robustness of farmer rice varieties (Oryza glaberrima and O. sativa) in West Africa. Our experiments in five West African countries showed that farmer varieties were tolerant of sub-optimal conditions, but employed a range of strategies to cope with stress. Varieties belonging to the species Oryza glaberrima – solely the product of farmer agency – were the most successful in adapting to a range of adverse conditions. Some of the farmer selections from within the indica and japonica subspecies of O. sativa also performed well in a range of conditions, but other farmer selections from within these two subspecies were mainly limited to more specific niches. The results contradict the rather common belief that farmer varieties are only of local value. Farmer varieties should be considered by breeding programmes and used (alongside improved varieties) in dissemination projects for rural food security. PMID:23536754

  20. Genetic analysis of a hybrid sterility gene that causes both pollen and embryo sac sterility in hybrids between Oryza sativa L. and Oryza longistaminata.

    Science.gov (United States)

    Chen, H; Zhao, Z; Liu, L; Kong, W; Lin, Y; You, S; Bai, W; Xiao, Y; Zheng, H; Jiang, L; Li, J; Zhou, J; Tao, D; Wan, J

    2017-09-01

    Oryza longistaminata originates from African wild rice and contains valuable traits conferring tolerance to biotic and abiotic stress. However, interspecific crosses between O. longistaminata and Oryza sativa cultivars are hindered by reproductive barriers. To dissect the mechanism of interspecific hybrid sterility, we developed a near-isogenic line (NIL) using indica variety RD23 as the recipient parent and O. longistaminata as the donor parent. Both pollen and embryo sac semi-sterility were observed in F 1 hybrids between RD23 and NIL. Cytological analysis demonstrated that pollen abortion in F 1 hybrids occurred at the early bi-nucleate stage due to a failure of the first mitosis in microspores. Partial embryo sacs in the F 1 hybrids were defective during the functional megaspore formation stage. Most notably, nearly half of the male or female gametes were aborted in heterozygotes S40 i S40 l , regardless of their genotypes. Thus, S40 was indicated as a one-locus sporophytic sterility gene controlling both male and female fertility in hybrids between RD23 and O. longistaminata. A population of 16 802 plants derived from the hybrid RD23/NIL-S40 was developed to fine-map S40. Finally, the S40 locus was delimited to an 80-kb region on the short arm of chromosome 1 in terms with reference sequences of cv. 93-11. Eight open reading frames (ORFs) were localized in this region. On the basis of gene expression and genomic sequence analysis, ORF5 and ORF8 were identified as candidate genes for the S40 locus. These results are helpful in cloning the S40 gene and marker-assisted transferring of the corresponding neutral allele in rice breeding programs.

  1. Comparative analysis of the small RNA transcriptomes of Pinus contorta and Oryza sativa.

    Science.gov (United States)

    Morin, Ryan D; Aksay, Gozde; Dolgosheina, Elena; Ebhardt, H Alexander; Magrini, Vincent; Mardis, Elaine R; Sahinalp, S Cenk; Unrau, Peter J

    2008-04-01

    The diversity of microRNAs and small-interfering RNAs has been extensively explored within angiosperms by focusing on a few key organisms such as Oryza sativa and Arabidopsis thaliana. A deeper division of the plants is defined by the radiation of the angiosperms and gymnosperms, with the latter comprising the commercially important conifers. The conifers are expected to provide important information regarding the evolution of highly conserved small regulatory RNAs. Deep sequencing provides the means to characterize and quantitatively profile small RNAs in understudied organisms such as these. Pyrosequencing of small RNAs from O. sativa revealed, as expected, approximately 21- and approximately 24-nt RNAs. The former contained known microRNAs, and the latter largely comprised intergenic-derived sequences likely representing heterochromatin siRNAs. In contrast, sequences from Pinus contorta were dominated by 21-nt small RNAs. Using a novel sequence-based clustering algorithm, we identified sequences belonging to 18 highly conserved microRNA families in P. contorta as well as numerous clusters of conserved small RNAs of unknown function. Using multiple methods, including expressed sequence folding and machine learning algorithms, we found a further 53 candidate novel microRNA families, 51 appearing specific to the P. contorta library. In addition, alignment of small RNA sequences to the O. sativa genome revealed six perfectly conserved classes of small RNA that included chloroplast transcripts and specific types of genomic repeats. The conservation of microRNAs and other small RNAs between the conifers and the angiosperms indicates that important RNA silencing processes were highly developed in the earliest spermatophytes. Genomic mapping of all sequences to the O. sativa genome can be viewed at http://microrna.bcgsc.ca/cgi-bin/gbrowse/rice_build_3/.

  2. Indica rice (Oryza sativa, BR29 and IR64).

    Science.gov (United States)

    Datta, Karabi; Datta, Swapan Kumar

    2006-01-01

    Rice is the world's most important food crop. Indica-type rice provides the staple food for more than half of the world population. To satisfy the growing demand of the ever-increasing population, more sustained production of indica-type rice is needed. In addition, because of the high per capita consumption of indica rice, improvement of any traits including its nutritive value may have a significant positive health outcome for the rice-consuming population. Rice yield productivity is greatly affected by different biotic stresses, like diseases and insect pests, and abiotic stresses like drought, cold, and salinity. Attempts to improve resistance in rice to these stresses by conventional breeding through introgression of traits have limited success owing to a lack of resistance germplasm in the wild relatives. Gene transfer technology with genes from other sources can be used to make rice plants resistant or tolerant to insect pests, diseases, and different environmental stresses. For improving the nutritional value of the edible endosperm part of the rice, genes for increasing iron, beta-carotene, or better quality protein can be introduced in rice plants by genetic engineering. Different crops have been transformed using various gene transfer methods, such as protoplast transformation, biolistic, and Agrobacterium-mediated transformation. This chapter describes the Agrobacterium-mediated transformation protocol for indica-type rice. The selectable marker genes used are hygromycin phosphotransferase (hpt), neomycin phosphotransferase (nptII), or phosphomannose isomerase (pmi), and, accordingly, the selection agents are hygromycin, kanamycin (G418), or mannose, respectively.

  3. EKSPLORASI CENDAWAN ENDOFIT DARI TANAMAN PADI SEBAGAI AGENS PEMACU PERTUMBUHAN TANAMAN (The Exploration of Endophytic Fungi from Oryza sativa as Plant Growth Promoting Agents)

    OpenAIRE

    Wilia, Weni; Hayati, Islah; Ristyadi, Dwi

    2013-01-01

    Endophityc fungi have been successfully isolated from Oryza sativa atLaboratory of Plant Disease, Agriculture Faculty University of Jambi. Theaim of this research was to get endophityc fungi from Oryza sativa. Therewere three (3) candidates of endophityc fungi that have been successfullyisolated. Pathogenosity test which was done showed that all of fungi wereendophityc fungi. Those fungi were identified as endophityc fungi due to theseed of paddy could growth normally in pure culture of endop...

  4. Genetic variation and population structure in Oryza ...

    Indian Academy of Sciences (India)

    Oryza malampuzhaensis Krish. et Chand. ( 2 n = 4 x = 48 ; Poaceae, Oryza) is endemic to Western Ghats, South India, and shows a highly localized distribution over a small geographical area in this region. This is the most poorly understood taxon in genus Oryza and is often misidentified as O. officinalis owing to their close ...

  5. Development and validation of cross-transferable and polymorphic DNA markers for detecting alien genome introgression in Oryza sativa from Oryza brachyantha.

    Science.gov (United States)

    Ray, Soham; Bose, Lotan K; Ray, Joshitha; Ngangkham, Umakanta; Katara, Jawahar L; Samantaray, Sanghamitra; Behera, Lambodar; Anumalla, Mahender; Singh, Onkar N; Chen, Meingsheng; Wing, Rod A; Mohapatra, Trilochan

    2016-08-01

    African wild rice Oryza brachyantha (FF), a distant relative of cultivated rice Oryza sativa (AA), carries genes for pests and disease resistance. Molecular marker assisted alien gene introgression from this wild species to its domesticated counterpart is largely impeded due to the scarce availability of cross-transferable and polymorphic molecular markers that can clearly distinguish these two species. Availability of the whole genome sequence (WGS) of both the species provides a unique opportunity to develop markers, which are cross-transferable. We observed poor cross-transferability (~0.75 %) of O. sativa specific sequence tagged microsatellite (STMS) markers to O. brachyantha. By utilizing the genome sequence information, we developed a set of 45 low cost PCR based co-dominant polymorphic markers (STS and CAPS). These markers were found cross-transferrable (84.78 %) between the two species and could distinguish them from each other and thus allowed tracing alien genome introgression. Finally, we validated a Monosomic Alien Addition Line (MAAL) carrying chromosome 1 of O. brachyantha in O. sativa background using these markers, as a proof of concept. Hence, in this study, we have identified a set molecular marker (comprising of STMS, STS and CAPS) that are capable of detecting alien genome introgression from O. brachyantha to O. sativa.

  6. Genome-wide analysis of potential cross-reactive endogenous allergens in rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Fang Chao Zhu

    2015-01-01

    Full Text Available The proteins in the food are the source of common allergic components to certain patients. Current lists of plant endogenous allergens were based on the medical/clinical reports as well as laboratory results. Plant genome sequences made it possible to predict and characterize the genome-wide of putative endogenous allergens in rice (Oryza sativa L.. In this work, we identified and characterized 122 candidate rice allergens including the 22 allergens in present databases. Conserved domain analysis also revealed 37 domains among rice allergens including one novel domain (histidine kinase-, DNA gyrase B-, and HSP90-like ATPase, PF13589 adding to the allergen protein database. Phylogenetic analysis of the allergens revealed the diversity among the Prolamin superfamily and DnaK protein family, respectively. Additionally, some allergens proteins clustered on the rice chromosome might suggest the molecular function during the evolution.

  7. Proximate Nutritional Evaluation of Gamma Irradiated Black Rice (Oryza sativa L. cv. Cempo ireng)

    Science.gov (United States)

    Riyatun; Suharyana; Ramelan, A. H.; Sutarno; Saputra, O. A.; Suryanti, V.

    2018-03-01

    Black rice is a type of pigmented rice with black bran covering the endosperm of the rice kernel. The main objective of the present study was to provide details information on the proximate composition of third generation of gamma irradiated black rice (Oryza sativa L. cv. Cempo ireng). In respect to the control, generally speaking, there were no significant changes of moisture, lipids, proteins, carbohydrates and fibers contents have been observed for the both gamma irradiated black rice. However, the 200-BR has slightly better nutritional value than that of 300-BR and the control. The mineral contents of 200-BR increased significantly of about 35% than the non-gamma irradiated black rice.

  8. Isolation of stress responsive Psb A gene from rice (Oryza sativa l.) using differential display.

    Science.gov (United States)

    Tyagi, Aruna; Chandra, Arti

    2006-08-01

    Differential display (DD) experiments were performed on drought-tolerant rice (Oryza sativa L.) genotype N22 to identify both upregulated and downregulated partial cDNAs with respect to moisture stress. DNA polymorphism was detected between drought-stressed and control leaf tissues on the DD gels. A partial cDNA showing differential expression, with respect to moisture stress was isolated from the gel. Northern blotting analysis was performed using this cDNA as a probe and it was observed that mRNA corresponding to this transcript was accumulated to high level in rice leaves under water deficit stress. At the DNA sequence level, the partial cDNA showed homology with psb A gene encoding for Dl protein.

  9. Toxic action of zinc on growth and enzyme activities of rice Oryza sativa L. seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Nag, P.; Nag, P.; Paul, A.K.; Mukherji, S.

    1984-01-01

    This paper provides information on the effects of toxic concentrations of zinc sulfate (ZnSO/sub 4/.7H/sub 2/O) on the growth and metabolism of rice Oryza sativa L. seedlings. Root growth inhibition was always more pronounced than was shoot growth inhibition. Root growth was completely inhibited at 40 m M concentration, whereas the magnitude of reduction of shoot length was only 56% at this concentration. Gibberellic acid (GA/sub 3/) was partially capable of relieving zinc inhibition. The activities of peroxidase, IAA oxidase and ascorbic acid oxidase of seedlings increased in response to zinc addition, whereas catalase and IAA synthetase decreased. All the hydrolyzing enzymes, viz., ..cap alpha..-amylase and phytase of endosperm together with RNase and ATPase of the embryo, showed distinct inhibition from the control, the exception being endosperm RNase which was stimulated under zinc treatment. 50 references, 6 figures.

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

    Science.gov (United States)

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

    2011-11-01

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

  11. Yield QTL analysis of Oryza sativa x O. glumaepatula introgression lines

    Directory of Open Access Journals (Sweden)

    Priscila Nascimento Rangel

    2013-03-01

    Full Text Available The objective of this work was to evaluate the yield performance of two generations (BC2F2 and BC2F9 of introgression lines developed from the interspecific cross between Oryza sativa and O. glumaepatula, and to identify the SSR markers associated to yield. The wild accession RS‑16 (O. glumaepatula was used as donor parent in the backcross with the high yielding cultivar Cica‑8 (O. sativa. A set of 114 BC2F1 introgression lines was genotyped with 141 polymorphic SSR loci distributed across the whole rice genome. Molecular analysis showed that in average 22% of the O. glumaepatula genome was introgressed into BC2F1 generation. Nine BC2F9 introgression lines had a significantly higher yield than the genitor Cica‑8, thus showing a positive genome interaction among cultivated rice and the wild O. glumaepatula. Seven QTL were identified in the overall BC2F2, with one marker interval (4879‑EST20 of great effect on yield. The alleles with positive effect on yield came from the cultivated parent Cica‑8.

  12. Physico-chemical and sensorial characteristics of rice (Oryza sativa L.) irradiated and the effect in Sitophilus oryzae L. development

    International Nuclear Information System (INIS)

    Zanao, Cintia Fernanda Pedroso

    2007-01-01

    Rice is exposed to injuries especially due to the attack of insects, which represent great qualitative and quantitative losses. The aim of the present research was to verify the viability of the gamma irradiation as rice (Oryza sativa L.) conservation method; its efficiency in the control of an important pest for stored grains Sitophilus oryzae L. and the effects that irradiation may present in irradiated grains in relation to the sensory aspect and starch alterations. Samples were composed of polished rice and the gamma irradiation dosages used were 0.5; 1.0; 3.0; and 5.0 kGy, and kept at room temperature. Analyses of the grain breakage percentages during processing and the longevity and reproduction of the rice weevil were performed. Analyses of the centesimal composition, phytic acid, apparent amylose content and starch paste properties were also conducted, as well as analyses of the rice color (instrumental) and acceptability (hedonic test), aimed at the determination of the raw and cooked rice sensory quality. It was verified that the gamma irradiation did not change the grain breakage percentage significantly and caused a negative effect on the insect development. Irradiation did not change the centesimal composition significantly. No significant values of phytic acid were found because during rice processing, the outer part (bran) containing 85-92% of total phytates was removed. Values from 17.33 to 18.44% for the apparent amylose content were found, and irradiation did not affect the rice starch amylose content significantly. The paste properties results were significantly changed, where reduction on the paste temperature, decrease on the time for the occurrence of the peak viscosity, reduction on the final viscosity values were observed. The retrogradation tendency became less intense in starches with increasing irradiation dosages. Statistical differences (p<0.05) were detected in the sensory aspect between irradiated and non-irradiated samples, and the

  13. Hybrid Weakness Found in the Backcross Progeny of an Inter-Specific Cross of Oryza Sativa / O. Glumaepatula

    Directory of Open Access Journals (Sweden)

    Sobrizal

    2009-01-01

    Full Text Available Hybrid breakdown expressed as sterility or weakness or both in F2 or later generations is considered to be a reproductive barrier between two distantly related taxa. Hybrid breakdown that showed poor growth habit with fertile seeds was found in the backcross progenies (BC4F2 which were derived from a cross between a cultivated rice Oryza sativa L. cv. Taichung 65 and a wild rice Oryza glumaepatula Steud (Acc. IRGC 105668 where Taichung 65 was used as a recurrent parent. Through segregation analysis of BC4F2 population, a novel gene for weakness was identified, and this gene was designated as hwf1 (hybrid weakness f-1. RFLP (Restriction Fragment Length Polymorphism analysis was employed to determine the chromosomal location of hwf1 gene. The result revealed that hwf1 was located between G3006 and C933 RFLP markers, with map distances of 0.5 cM and 1.9 cM, respectively, and co-segregated with C708, C820, and R288 on the short arm of chromosome 4. Since both O. glumaepatula (Acc. IRGC 105668 and Taichung 65 that was used as parents showed normal growth habit, the weakness in this study was assumed to be controlled by a set of complementary recessive genes. One of the complementary genes is hwf1 from O. glumaepatula, and another gene should be from Taichung 65, because the genetic background of the BC4F2 populations that were used for analysis is Taichung 65. The gene from Taichung 65 has not been identified yet, therefore, it is necessary to conduct the experiment for finding out the complement of hwf1 gene in near future.

  14. Hybrid Weakness Found In the Backcross Progeny of an Inter-Specific Cross of Oryza Sativa / O. Glumaepatula

    International Nuclear Information System (INIS)

    Sobrizal; Yoshimura, A

    2009-01-01

    Hybrid breakdown expressed as sterility or weakness or both in F 2 or later generations is considered to be a reproductive barrier between two distantly related taxa. Hybrid breakdown that showed poor growth habit with fertile seeds was found in the backcross progenies (BC 4 F 2 ) which were derived from a cross between a cultivated rice Oryza sativa L. cv. Taichung 65 and a wild rice Oryza glumaepatula Steud (Acc. IRGC 105668) where Taichung 65 was used as a recurrent parent. Through segregation analysis of BC 4 F 2 population, a novel gene for weakness was identified, and this gene was designated as hwf1 (hybrid weakness f-1). RFLP (Restriction Fragment Length Polymorphism) analysis was employed to determine the chromosomal location of hwf1 gene. The result revealed that hwf1 was located between G3006 and C933 RFLP markers, with map distances of 0.5 cM and 1.9 cM, respectively, and co-segregated with C708, C820, and R288 on the short arm of chromosome 4. Since both O. glumaepatula (Acc. IRGC 105668) and Taichung 65 that was used as parents showed normal growth habit, the weakness in this study was assumed to be controlled by a set of complementary recessive genes. One of the complementary genes is hwf1 from O. glumaepatula, and another gene should be from Taichung 65, because the genetic background of the BC 4 F 2 populations that were used for analysis is Taichung 65. The gene from Taichung 65 has not been identified yet, therefore, it is necessary to conduct the experiment for finding out the complement of hwf1 gene in near future. (author)

  15. Oryza sativa

    Indian Academy of Sciences (India)

    2014-04-25

    Apr 25, 2014 ... Gaps (marked with dashes) have been introduced to ..... Genomi-wide association study of flowering time and grain yield traits in a worldwide ... stages of programmed cell death in maize root cells by using comet assay and ...

  16. Assessing hybrid sterility in Oryza glaberrima x O. sativa hybrid progenies by PCR marker analysis and crossing with wide compatibility varieties.

    Science.gov (United States)

    Heuer, Sigrid; Miézan, Kouamé M

    2003-09-01

    Interspecific crossing of the African indigenous rice Oryza glaberrima with Oryza sativa cultivars is hindered by crossing barriers causing 100% spikelet sterility in F(1) hybrids. Since hybrids are partially female fertile, fertility can be restored by back crossing (BC) to a recurrent male parent. Distinct genetic models on spikelet sterility have been developed predicting, e.g., the existence of a gamete eliminator and/or a pollen killer. Linkage of sterility to the waxy starch synthase gene and the chromogen gene C, both located on chromosome 6, have been demonstrated. We selected a segregating BC(2)F(3) population of semi-sterile O. glaberrima x O. sativa indica hybrid progenies for analyses with PCR markers located at the respective chromosome-6 region. These analyses revealed that semi-sterile plants were heterozygous for a marker (OSR25) located in the waxy promoter, whereas fertile progenies were homozygous for the O. glaberrima allele. Adjacent markers showed no linkage to spikelet sterility. Semi-sterility of hybrid progenies was maintained at least until the F(4) progeny generation, suggesting the existence of a pollen killer in this plant material. Monitoring of reproductive plant development showed that spikelet sterility was at least partially due to an arrest of pollen development at the microspore stage. In order to address the question whether genes responsible for F(1) sterility in intraspecific hybrids ( O. sativa indica x japonica) also cause spikelet sterility in interspecific hybrids, crossings with wide compatibility varieties (WCV) were performed. WCV accessions possess "neutral" S-loci ( S(n)) improving fertility in intraspecific hybrids. This experiment showed that the tested S(n)-loci had no fertility restoring effect in F(1) interspecific hybrids. Pollen development was completely arrested at the microspore stage and grains were never obtained after selfing. This suggests that distinct or additional S-loci are responsible for sterility

  17. Genotype × environment interactions of yield traits in backcross introgression lines derived from Oryza sativa cv. Swarna /Oryza nivara

    Directory of Open Access Journals (Sweden)

    Divya Balakrishnan

    2016-10-01

    Full Text Available Advanced backcross introgression lines (BILs developed from crosses of Oryza sativa var. Swarna/O. nivara accessions were grown and evaluated for yield and related traits. Trials were conducted for consecutive three seasons in field conditions in a randomized complete block design with three replications. Data on yield traits under irrigated conditions were analyzed using the Additive Main Effect and Multiplicative Interaction (AMMI, Genotype and Genotype × Environment Interaction (GGE and modified rank-sum statistic (YSi for yield stability. BILs viz., G3 (14S and G6 (166S showed yield stability across the seasons along with high mean yield performance. G3 is early in flowering with high yield and has good grain quality and medium height, hence could be recommended for most of the irrigated locations. G6 is a late duration genotype, with strong culm strength, high grain number and panicle weight. G6 has higher yield and stability than Swarna but has Swarna grain type. Among the varieties tested DRRDhan 40 and recurrent parent Swarna showed stability for yield traits across the seasons. The component traits thousand grain weight, panicle weight, panicle length, grain number and plant height explained highest genotypic percentage over environment and interaction factors and can be prioritized to dissect stable QTLs/ genes. These lines were genotyped using microsatellite markers covering the entire rice genome and also using a set of markers linked to previously reported yield QTLs. It was observed that wild derived lines with more than 70% of recurrent parent genome were stable and showed enhanced yield levels compared to genotypes with higher donor genome introgressions.

  18. Transfer of bacterial blight resistance from Oryza meyeriana to O.Sativa L.by asymmetric somatic hybridization

    Institute of Scientific and Technical Information of China (English)

    ZHU Yongsheng; CHEN Baotang; YU Shunwu; ZHANG Duanpin; ZHANG Xueqin; YAN Qiusheng

    2004-01-01

    Asymmetric somatic hybrid plants were produced between cultivated rice (Oryza sativa L.) and wild species [O. Meyeriana (Zoll. etMor, exSteud.)] with high resistance to rice bacterial blight. X-ray-irradiated protoplasts of the wild species were used as donor and chemically fused with iodoacetamide-inactivated protoplasts of rice cv. 02428to produce hybrids. Seventy-two plants were regenerated from 623 calli based on metabolic complementation. The morphological characters of the plants closely resembled that of the rice. Simple sequence repeats were employed to identify their hybridity. Cytological analysis of root-tips revealed that their chromosome number varied in the range of 27-38. The somatic hybrids were inoculated with strains of Xanthamonas oryzae pv. Oryzae at adult growth stage and demonstrated the resistance to bacterial blight introgression from the O. Meyeriana.

  19. Macromolecular Traits in the African Rice Oryza glaberrima and in Glaberrima/Sativa Crosses, and Their Relevance to Processing.

    Science.gov (United States)

    Marengo, Mauro; Barbiroli, Alberto; Bonomi, Francesco; Casiraghi, Maria Cristina; Marti, Alessandra; Pagani, Maria Ambrogina; Manful, John; Graham-Acquaah, Seth; Ragg, Enzio; Fessas, Dimitrios; Hogenboom, Johannes A; Iametti, Stefania

    2017-10-01

    Molecular properties of proteins and starch were investigated in 2 accessions of Oryza glaberrima and Oryza sativa, and in one NERICA cross between the 2 species, to assess traits that could be relevant to transformation into specific foods. Protein nature and organization in O. glaberrima were different from those in O. sativa and in NERICA. Despite the similar cysteine content in all samples, thiol accessibility in O. glaberrima proteins was higher than in NERICA or in O. sativa. Inter-protein disulphide bonds were important for the formation of protein aggregates in O. glaberrima, whereas non-covalent protein-protein interactions were relevant in NERICA and O. sativa. DSC and NMR studies indicated only minor differences in the structure of starch in these species, as also made evident by their microstructural features. Nevertheless, starch gelatinization in O. glaberrima was very different from what was observed in O. sativa and NERICA. The content of soluble species in gelatinized starch from the various species in the presence/absence of treatments with specific enzymes indicated that release of small starch breakdown products was lowest in O. glaberrima, in particular from the amylopectin component. These findings may explain the low glycemic index of O. glaberrima, and provide a rationale for extending the use of O. glaberrima in the production of specific rice-based products, thus improving the economic value and the market appeal of African crops. The structural features of proteins and starch in O. glaberrima are very different from those in O. sativa and in the NERICA cross. These results appear useful as for extending the use of O. glaberrima cultivars in the design and production of specific rice-based products (for example, pasta), that might, in turn, improve the economic value and the market appeal of locally sourced raw materials, by introducing added-value products on the African market. © 2017 Institute of Food Technologists®.

  20. Characterization and genetic mapping of a Photoperiod-sensitive dwarf 1 locus in rice (Oryza sativa L.).

    Science.gov (United States)

    Li, Riqing; Xia, Jixing; Xu, Yiwei; Zhao, Xiucai; Liu, Yao-Guang; Chen, Yuanling

    2014-01-01

    Plant height is an important agronomic trait for crop architecture and yield. Most known factors determining plant height function in gibberellin or brassinosteroid biosynthesis or signal transduction. Here, we report a japonica rice (Oryza sativa ssp. japonica) dominant dwarf mutant, Photoperiod-sensitive dwarf 1 (Psd1). The Psd1 mutant showed impaired cell division and elongation, and a severe dwarf phenotype under long-day conditions, but nearly normal growth in short-day. The plant height of Psd1 mutant could not be rescued by gibberellin or brassinosteroid treatment. Genetic analysis with R1 and F2 populations determined that Psd1 phenotype was controlled by a single dominant locus. Linkage analysis with 101 tall F2 plants grown in a long-day season, which were derived from a cross between Psd1 and an indica cultivar, located Psd1 locus on chromosome 1. Further fine-mapping with 1017 tall F2 plants determined this locus on an 11.5-kb region. Sequencing analysis of this region detected a mutation site in a gene encoding a putative lipid transfer protein; the mutation produces a truncated C-terminus of the protein. This study establishes the genetic foundation for understanding the molecular mechanisms regulating plant cell division and elongation mediated by interaction between genetic and environmental factors.

  1. Mapping and marker-assisted selection of a brown planthopper resistance gene bph2 in rice (Oryza sativa L.).

    Science.gov (United States)

    Sun, Li-Hong; Wang, Chun-Ming; Su, Chang-Chao; Liu, Yu-Qiang; Zhai, Hu-Qu; Wan, Jian-Min

    2006-08-01

    Nilaparvata lugens Stål (brown planthopper, BPH), is one of the major insect pests of rice (Oryza sativa L.) in the temperate rice-growing region. In this study, ASD7 harboring a BPH resistance gene bph2 was crossed to a susceptible cultivar C418, a japonica restorer line. BPH resistance was evaluated using 134 F2:3 lines derived from the cross between "ASD7" and "C418". SSR assay and linkage analysis were carried out to detect bph2. As a result, the resistant gene bph2 in ASD7 was successfully mapped between RM7102 and RM463 on the long arm of chromosome 12, with distances of 7.6 cM and 7.2 cM, respectively. Meanwhile, both phenotypic selection and marker-assisted selection (MAS) were conducted in the BC1F1 and BC2F1 populations. Selection efficiencies of RM7102 and RM463 were determined to be 89.9% and 91.2%, respectively. It would be very beneficial for BPH resistance improvement by using MAS of this gene.

  2. Two solanesyl diphosphate synthases with different subcellular localizations and their respective physiological roles in Oryza sativa.

    Science.gov (United States)

    Ohara, Kazuaki; Sasaki, Kanako; Yazaki, Kazufumi

    2010-06-01

    Long chain prenyl diphosphates are crucial biosynthetic precursors of ubiquinone (UQ) in many organisms, ranging from bacteria to humans, as well as precursors of plastoquinone in photosynthetic organisms. The cloning and characterization of two solanesyl diphosphate synthase genes, OsSPS1 and OsSPS2, in Oryza sativa is reported here. OsSPS1 was highly expressed in root tissue whereas OsSPS2 was found to be high in both leaves and roots. Enzymatic characterization using recombinant proteins showed that both OsSPS1 and OsSPS2 could produce solanesyl diphosphates as their final product, while OsSPS1 showed stronger activity than OsSPS2. However, an important biological difference was observed between the two genes: OsSPS1 complemented the yeast coq1 disruptant, which does not form UQ, whereas OsSPS2 only very weakly complemented the growth defect of the coq1 mutant. HPLC analyses showed that both OsSPS1 and OsSPS2 yeast transformants produced UQ9 instead of UQ6, which is the native yeast UQ. According to the complementation study, the UQ9 levels in OsSPS2 transformants were much lower than that of OsSPS1. Green fluorescent protein fusion analyses showed that OsSPS1 localized to mitochondria, while OsSPS2 localized to plastids. This suggests that OsSPS1 is involved in the supply of solanesyl diphosphate for ubiquinone-9 biosynthesis in mitochondria, whereas OsSPS2 is involved in providing solanesyl diphosphate for plastoquinone-9 formation. These findings indicate that O. sativa has a different mechanism for the supply of isoprenoid precursors in UQ biosynthesis from Arabidopsis thaliana, in which SPS1 provides a prenyl moiety for UQ9 at the endoplasmic reticulum.

  3. Vinegar rice (Oryza sativa L. produced by a submerged fermentation process from alcoholic fermented rice

    Directory of Open Access Journals (Sweden)

    Wilma Aparecida Spinosa

    2015-03-01

    Full Text Available Considering the limited availability of technology for the production of rice vinegar and also due to the potential consumer product market, this study aimed to use alcoholic fermented rice (rice wine (Oryza sativa L. for vinegar production. An alcoholic solution with 6.28% (w/v ethanol was oxidized by a submerged fermentation process to produce vinegar. The process of acetic acid fermentation occurred at 30 ± 0.3°C in a FRINGS® Acetator (Germany for the production of vinegar and was followed through 10 cycles. The vinegar had a total acidity of 6.85% (w/v, 0.17% alcohol (w/v, 1.26% (w/v minerals and 1.78% (w/v dry extract. The composition of organic acids present in rice vinegar was: cis-aconitic acid (6 mg/L, maleic acid (3 mg/L, trans-aconitic acid (3 mg/L, shikimic + succinic acid (4 mg/L, lactic acid (300 mg/L, formic acid (180 mg/L, oxalic acid (3 mg/L, fumaric acid (3 mg/L and itaconic acid (1 mg/L.

  4. An improved Agrobacterium-mediated transformation of recalcitrant indica rice (Oryza sativa L.) cultivars.

    Science.gov (United States)

    Shri, Manju; Rai, Arti; Verma, Pankaj Kumar; Misra, Prashant; Dubey, Sonali; Kumar, Smita; Verma, Sikha; Gautam, Neelam; Tripathi, Rudra Deo; Trivedi, Prabodh Kumar; Chakrabarty, Debasis

    2013-04-01

    Agrobacterium-mediated transformation of indica rice varieties has been quite difficult as these are recalcitrant to in vitro responses. In the present study, we established a high-efficiency Agrobacterium tumefaciens-mediated transformation system of rice (Oryza sativa L. ssp. indica) cv. IR-64, Lalat, and IET-4786. Agrobacterium strain EHA-101 harboring binary vector pIG121-Hm, containing a gene encoding for β-glucuronidase (GUS) and hygromycin resistance, was used in the transformation experiments. Manipulation of different concentrations of acetosyringone, days of co-culture period, bacterial suspension of different optical densities (ODs), and the concentrations of L-cysteine in liquid followed by solid co-culture medium was done for establishing the protocol. Among the different co-culture periods, 5 days of co-culture with bacterial cells (OD600 nm = 0.5-0.8) promoted the highest frequency of transformation (83.04 %) in medium containing L-cysteine (400 mg l(-1)). Putative transformed plants were analyzed for the presence of a transgene through genomic PCR and GUS histochemical analyses. Our results also suggest that different cultural conditions and the addition of L-cysteine in the co-culture medium improve the Agrobacterium-mediated transformation frequencies from an average of 12.82 % to 33.33 % in different indica rice cultivars.

  5. A study of technetium 99 uptake by irrigated rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Vandecasteele, C.M.; De Becker, R.; Tang Van Hai; Myttenaere, C.

    1983-01-01

    The absorption of technetium 99 (an important fission product which can be released in the environment at different steps of the nuclear fuel cycle) by rice (Oryza sativa L.) was studied in nutrient solutions and in flooded soils with contaminated water. The absorption kinetics established in water culture (continuous flowing system) for 99 Tc concentrations ranging from 0.017 to 17 μCi.I - 1 revealed two phases: the former corresponds to the diffusion in the apparent free spaces and the second, which is linear, represents the transfer of 99 Tc from the external medium into the root cells as well as its translocation to the leaves. The study of the desorption mechanism confirmed the existence of these compartments, the second one containing more than 95% of the total activity of the plant. The biological half-life of 99 Tc of the second compartment is so high that decontamination of the plant may not be expected. In soils, toxicity symptoms were observed for a 99 Tc water concentration of 17 μCi.I - 1 . The transfer factors calculated in irrigated soils are very high (>10 3 for the leafy shoots) and the distribution of 99 Tc between the different organs waries with the concentration used. More than 90% of 99 Tc is found in the leafy shoots meanwhile 1% of the plant total activity is only found in the caryopses [fr

  6. Genetic diversity analysis of Cuban traditional rice (Oryza sativa L. varieties based on microsatellite markers

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    Alba Alvarez

    2007-01-01

    Full Text Available Microsatellite polymorphism was studied in a sample of 39 traditional rice (Oryza sativa L. varieties and 11 improved varieties widely planted in Cuba. The study was aimed at assessing the extent of genetic variation in traditional and improved varieties and to establish their genetic relationship for breeding purposes. Heterozygosity was analyzed at each microsatellite loci and for each genotype using 10 microsatellite primer pairs. Between varieties genetic relationship was estimated. The number of alleles per microsatellite loci was 4 to 8, averaging 6.6 alleles per locus. Higher heterozygosity (H was found in traditional varieties (H TV = 0.72 than in improved varieties (H IV = 0.42, and 68% of the total microsatellite alleles were found exclusively in the traditional varieties. Genetic diversity, represented by cluster analysis, indicated three different genetic groups based on their origin. Genetic relationship estimates based on the proportion of microsatellite loci with shared alleles indicated that the majority of traditional varieties were poorly related to the improved varieties. We also discuss the more efficient use of the available genetic diversity in future programs involving genetic crosses.

  7. Germination and plantlet regeneration of encapsulated microshoots of aromatic rice (Oryza sativa L. Cv. MRQ 74).

    Science.gov (United States)

    Taha, Rosna Mat; Saleh, Azani; Mahmad, Noraini; Hasbullah, Nor Azlina; Mohajer, Sadegh

    2012-01-01

    Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. In the present study, 3-5 mm microshoots of Oryza sativa L. Cv. MRQ 74 were used as explant sources for obtaining synthetic seeds. Microshoots were induced from stem explants on Murashige and Skoog (MS) medium supplemented with 1.5 mg/L benzylaminopurine (BAP). They were encapsulated in 3% (w/v) sodium alginate, 3% sucrose, 0.1 mg/L BAP, and 0.1 mg/L α-Naphthalene acetic acid (NAA). Germination and plantlet regeneration of the encapsulated seeds were tested by culturing them on various germination media. The effect of storage period (15-30 days) was also investigated. The maximum germination and plantlet regeneration (100.0%) were recorded on MS media containing 3% sucrose and 0.8% agar with and without 0.1 mg/L BAP. However, a low germination rate (6.67%) was obtained using top soil as a sowing substrate. The germination rate of the encapsulated microshoots decreased from 93.33% to 3.33% after 30 days of storage at 4°C in the dark. Therefore, further research is being done to improve the germination rate of the synthetic seeds.

  8. Germination and Plantlet Regeneration of Encapsulated Microshoots of Aromatic Rice (Oryza sativa L. Cv. MRQ 74

    Directory of Open Access Journals (Sweden)

    Rosna Mat Taha

    2012-01-01

    Full Text Available Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. In the present study, 3–5 mm microshoots of Oryza sativa L. Cv. MRQ 74 were used as explant sources for obtaining synthetic seeds. Microshoots were induced from stem explants on Murashige and Skoog (MS medium supplemented with 1.5 mg/L benzylaminopurine (BAP. They were encapsulated in 3% (w/v sodium alginate, 3% sucrose, 0.1 mg/L BAP, and 0.1 mg/L α-Naphthalene acetic acid (NAA. Germination and plantlet regeneration of the encapsulated seeds were tested by culturing them on various germination media. The effect of storage period (15–30 days was also investigated. The maximum germination and plantlet regeneration (100.0% were recorded on MS media containing 3% sucrose and 0.8% agar with and without 0.1 mg/L BAP. However, a low germination rate (6.67% was obtained using top soil as a sowing substrate. The germination rate of the encapsulated microshoots decreased from 93.33% to 3.33% after 30 days of storage at 4°C in the dark. Therefore, further research is being done to improve the germination rate of the synthetic seeds.

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

    Science.gov (United States)

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

    2015-11-01

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

  10. Quantitative Classification of Rice (Oryza sativa L.) Root Length and Diameter Using Image Analysis.

    Science.gov (United States)

    Gu, Dongxiang; Zhen, Fengxian; Hannaway, David B; Zhu, Yan; Liu, Leilei; Cao, Weixing; Tang, Liang

    2017-01-01

    Quantitative study of root morphological characteristics of plants is helpful for understanding the relationships between their morphology and function. However, few studies and little detailed and accurate information of root characteristics were reported in fine-rooted plants like rice (Oryza sativa L.). The aims of this study were to quantitatively classify fine lateral roots (FLRs), thick lateral roots (TLRs), and nodal roots (NRs) and analyze their dynamics of mean diameter (MD), lengths and surface area percentage with growth stages in rice plant. Pot experiments were carried out during three years with three rice cultivars, three nitrogen (N) rates and three water regimes. In cultivar experiment, among the three cultivars, root length of 'Yangdao 6' was longest, while the MD of its FLR was the smallest, and the mean diameters for TLR and NR were the largest, the surface area percentage (SAP) of TLRs (SAPT) was the highest, indicating that Yangdao 6 has better nitrogen and water uptake ability. High N rate increased the length of different types of roots and increased the MD of lateral roots, decreased the SAP of FLRs (SAPF) and TLRs, but increased the SAP of NRs (SAPN). Moderate decrease of water supply increased root length and diameter, water stress increased the SAPF and SAPT, but decreased SAPN. The quantitative results indicate that rice plant tends to increase lateral roots to get more surface area for nitrogen and water uptake when available assimilates are limiting under nitrogen and water stress environments.

  11. 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.

  12. Arsenic uptake and accumulation in rice (Oryza sativa L.) with selenite fertilization and water management.

    Science.gov (United States)

    Wan, Yanan; Camara, Aboubacar Younoussa; Huang, Qingqing; Yu, Yao; Wang, Qi; Li, Huafen

    2018-07-30

    The accumulation of arsenic (As) in rice grain is a potential threat to human health. Our study investigated the possible mediatory role of selenite fertilization on As uptake and accumulation by rice (Oryza sativa L.) under different water management regimes (aerobic or flooded) in a pot experiment. Soil solutions were also extracted during the growing season to monitor As dynamics. Results showed that As contents in the soil solutions, seedlings, and mature rice were higher under flooded than under aerobic water management. Under aerobic conditions, selenite additions slightly increased As concentrations in soil solutions (in the last two samplings), but decreased As levels in rice plants. Relative to the control, 0.5 mg kg -1 selenite decreased rice grain As by 27.5%. Under flooded conditions, however, selenite additions decreased As in soil solutions, while increased As in rice grain. Tendencies also showed that selenite additions decreased the proportion of As in rice shoots both at the seedling stage and maturity, and were more effective in aerobic soil. Our results demonstrate that the effect of selenite fertilizer on As accumulation by rice is related to water management. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. Quantitative Classification of Rice (Oryza sativa L.) Root Length and Diameter Using Image Analysis

    Science.gov (United States)

    Gu, Dongxiang; Zhen, Fengxian; Hannaway, David B.; Zhu, Yan; Liu, Leilei; Cao, Weixing; Tang, Liang

    2017-01-01

    Quantitative study of root morphological characteristics of plants is helpful for understanding the relationships between their morphology and function. However, few studies and little detailed and accurate information of root characteristics were reported in fine-rooted plants like rice (Oryza sativa L.). The aims of this study were to quantitatively classify fine lateral roots (FLRs), thick lateral roots (TLRs), and nodal roots (NRs) and analyze their dynamics of mean diameter (MD), lengths and surface area percentage with growth stages in rice plant. Pot experiments were carried out during three years with three rice cultivars, three nitrogen (N) rates and three water regimes. In cultivar experiment, among the three cultivars, root length of ‘Yangdao 6’ was longest, while the MD of its FLR was the smallest, and the mean diameters for TLR and NR were the largest, the surface area percentage (SAP) of TLRs (SAPT) was the highest, indicating that Yangdao 6 has better nitrogen and water uptake ability. High N rate increased the length of different types of roots and increased the MD of lateral roots, decreased the SAP of FLRs (SAPF) and TLRs, but increased the SAP of NRs (SAPN). Moderate decrease of water supply increased root length and diameter, water stress increased the SAPF and SAPT, but decreased SAPN. The quantitative results indicate that rice plant tends to increase lateral roots to get more surface area for nitrogen and water uptake when available assimilates are limiting under nitrogen and water stress environments. PMID:28103264

  14. Influence of cooking on anthocyanins in black rice (Oryza sativa L. japonica var. SBR).

    Science.gov (United States)

    Hiemori, Miki; Koh, Eunmi; Mitchell, Alyson E

    2009-03-11

    The composition and thermal stability of anthocyanins in black rice (Oryza sativa L. japonica var. SBR) produced in California were investigated. Six anthocyanin pigments were identified and quantified by high performance liquid chromatography using photo diode-array detection (HPLC-PDA) and electrospray ionization mass spectrometry [LC-(ESI)MS/MS]. The predominant anthocyanins are cyanidin-3-glucoside (572.47 microg/g; 91.13% of total) and peonidin-3-glucoside (29.78 microg/g; 4.74% of total). Minor constituents included three cyanidin-dihexoside isomers and one cyanidin hexoside. Thermal stability of anthocyanins was assessed in rice cooked using a rice cooker, pressure cooker, or on a gas range. All cooking methods caused significant (P rice cooker (74.2%) and gas range (65.4%). Conversely, levels of protocatechuic acid increased 2.7 to 3.4 times in response to all cooking methods. These findings indicate that cooking black rice results in the thermal degradation of cyanidin-3-glucoside and concomitant production of protocatechuic acid.

  15. Biochemical and structural properties of cyanases from Arabidopsis thaliana and Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Dan Qian

    Full Text Available Cyanate is toxic to all organisms. Cyanase converts cyanate to CO₂ and NH₃ in a bicarbonate-dependent reaction. The biophysical functions and biochemical characteristics of plant cyanases are poorly studied, although it has been investigated in a variety of proteobacteria, cyanobacteria and fungi. In this study, we characterised plant cyanases from Arabidopsis thaliana and Oryza sativa (AtCYN and OsCYN. Prokaryotic-expressed AtCYN and OsCYN both showed cyanase activity in vitro. Temperature had a similar influence on the activity of both cyanases, but pH had a differential impact on AtCYN and OsCYN activity. Homology modelling provided models of monomers of AtCYN and OsCYN, and a coimmunoprecipitation assay and gel filtration indicated that AtCYN and OsCYN formed homodecamers. The analysis of single-residue mutants of AtCYN indicated that the conserved catalytic residues also contributed to the stability of the homodecamer. KCNO treatment inhibited Arabidopsis germination and early seedling growth. Plants containing AtCYN or OsCYN exhibited resistance to KCNO stress, which demonstrated that one role of cyanases in plants is detoxification. Transcription level of AtCYN was higher in the flower than in other organs of Arabidopsis. AtCYN transcription was not significantly affected by KCNO treatment in Arabidopsis, but was induced by salt stress. This research broadens our knowledge on plant detoxification of cyanate via cyanase.

  16. Curated genome annotation of Oryza sativa ssp. japonica and comparative genome analysis with Arabidopsis thaliana

    Science.gov (United States)

    Itoh, Takeshi; Tanaka, Tsuyoshi; Barrero, Roberto A.; Yamasaki, Chisato; Fujii, Yasuyuki; Hilton, Phillip B.; Antonio, Baltazar A.; Aono, Hideo; Apweiler, Rolf; Bruskiewich, Richard; Bureau, Thomas; Burr, Frances; Costa de Oliveira, Antonio; Fuks, Galina; Habara, Takuya; Haberer, Georg; Han, Bin; Harada, Erimi; Hiraki, Aiko T.; Hirochika, Hirohiko; Hoen, Douglas; Hokari, Hiroki; Hosokawa, Satomi; Hsing, Yue; Ikawa, Hiroshi; Ikeo, Kazuho; Imanishi, Tadashi; Ito, Yukiyo; Jaiswal, Pankaj; Kanno, Masako; Kawahara, Yoshihiro; Kawamura, Toshiyuki; Kawashima, Hiroaki; Khurana, Jitendra P.; Kikuchi, Shoshi; Komatsu, Setsuko; Koyanagi, Kanako O.; Kubooka, Hiromi; Lieberherr, Damien; Lin, Yao-Cheng; Lonsdale, David; Matsumoto, Takashi; Matsuya, Akihiro; McCombie, W. Richard; Messing, Joachim; Miyao, Akio; Mulder, Nicola; Nagamura, Yoshiaki; Nam, Jongmin; Namiki, Nobukazu; Numa, Hisataka; Nurimoto, Shin; O’Donovan, Claire; Ohyanagi, Hajime; Okido, Toshihisa; OOta, Satoshi; Osato, Naoki; Palmer, Lance E.; Quetier, Francis; Raghuvanshi, Saurabh; Saichi, Naomi; Sakai, Hiroaki; Sakai, Yasumichi; Sakata, Katsumi; Sakurai, Tetsuya; Sato, Fumihiko; Sato, Yoshiharu; Schoof, Heiko; Seki, Motoaki; Shibata, Michie; Shimizu, Yuji; Shinozaki, Kazuo; Shinso, Yuji; Singh, Nagendra K.; Smith-White, Brian; Takeda, Jun-ichi; Tanino, Motohiko; Tatusova, Tatiana; Thongjuea, Supat; Todokoro, Fusano; Tsugane, Mika; Tyagi, Akhilesh K.; Vanavichit, Apichart; Wang, Aihui; Wing, Rod A.; Yamaguchi, Kaori; Yamamoto, Mayu; Yamamoto, Naoyuki; Yu, Yeisoo; Zhang, Hao; Zhao, Qiang; Higo, Kenichi; Burr, Benjamin; Gojobori, Takashi; Sasaki, Takuji

    2007-01-01

    We present here the annotation of the complete genome of rice Oryza sativa L. ssp. japonica cultivar Nipponbare. All functional annotations for proteins and non-protein-coding RNA (npRNA) candidates were manually curated. Functions were identified or inferred in 19,969 (70%) of the proteins, and 131 possible npRNAs (including 58 antisense transcripts) were found. Almost 5000 annotated protein-coding genes were found to be disrupted in insertional mutant lines, which will accelerate future experimental validation of the annotations. The rice loci were determined by using cDNA sequences obtained from rice and other representative cereals. Our conservative estimate based on these loci and an extrapolation suggested that the gene number of rice is ∼32,000, which is smaller than previous estimates. We conducted comparative analyses between rice and Arabidopsis thaliana and found that both genomes possessed several lineage-specific genes, which might account for the observed differences between these species, while they had similar sets of predicted functional domains among the protein sequences. A system to control translational efficiency seems to be conserved across large evolutionary distances. Moreover, the evolutionary process of protein-coding genes was examined. Our results suggest that natural selection may have played a role for duplicated genes in both species, so that duplication was suppressed or favored in a manner that depended on the function of a gene. PMID:17210932

  17. Can Rice (Oryza sativa) Mitigate Pesticides and Nutrients in Agricultural Runoff?

    Science.gov (United States)

    Moore, M T; Locke, M A

    2018-01-01

    Phytoremediation of nutrients and pesticides in runoff is a growing conservation effort, particularly in agriculturally intensive areas such as the lower Mississippi River Valley. In the current study, rice (Oryza sativa) was examined for its mitigation capacity of nitrogen, phosphorus, diazinon, and permethrin. Twenty-two high density polyethylene circular containers (56 cm x 45 cm) were used as mesocosms, with 12 mesocosms planted with rice and 10 mesocosms remaining unvegetated. Mesocosms were hydraulically connected and arranged in a series of two, with each system providing a 4 h hydraulic retention time (HRT) for a total system retention time of 8 h. Two treatments (RICE/RICE and RICE/BARE) of four replicates each were utilized, with three replicates of controls (BARE/BARE). Systems with RICE/RICE (8 h HRT) significantly reduced diazinon (p = 0.0126), cis-permethrin (p = 0.0442), filtered orthophosphate (p = 0.0058), and total orthophosphate (p = 0.0123) compared to control systems. No significant differences were noted for trans-permethrin, nitrate, or ammonium. Results indicate promise in phytoremediation of agricultural runoff by rice. If further studies reveal contaminants are not transferred into seeds, then rice could potentially serve as both a remediation tool and food source in countries facing agricultural pollution challenges.

  18. Metabolomics analysis of TiO2 nanoparticles induced toxicological effects on rice (Oryza sativa L.).

    Science.gov (United States)

    Wu, Biying; Zhu, Lizhong; Le, X Chris

    2017-11-01

    The wide occurrence and high environmental concentration of titanium dioxide nanoparticles (nano-TiO 2 ) have raised concerns about their potential toxic effects on crops. In this study, we employed a GC-MS-based metabolomic approach to investigate the potential toxicity of nano-TiO 2 on hydroponically-cultured rice (Oryza sativa L.) after exposed to 0, 100, 250 or 500 mg/L of nano-TiO 2 for fourteen days. Results showed that the biomass of rice was significantly decreased and the antioxidant defense system was significantly disturbed after exposure to nano-TiO 2 . One hundred and five identified metabolites showed significant difference compared to the control, among which the concentrations of glucose-6-phosphate, glucose-1-phosphate, succinic and isocitric acid were increased most, while the concentrations of sucrose, isomaltulose, and glyoxylic acid were decreased most. Basic energy-generating ways including tricarboxylic acid cycle and the pentose phosphate pathway, were elevated significantly while the carbohydrate synthesis metabolism including starch and sucrose metabolism, and glyoxylate and dicarboxylate metabolism were inhibited. However, the biosynthetic formation of most of the identified fatty acids, amino acids and secondary metabolites which correlated to crop quality, were increased. The results suggest that the metabolism of rice plants is distinctly disturbed after exposure to nano-TiO 2 , and nano-TiO 2 would have a mixed effect on the yield and quality of rice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Comprehensive phenotypic analysis of rice (Oryza sativa) response to salinity stress

    KAUST Repository

    Pires, Inês S.

    2015-07-22

    Increase in soil salinity levels is becoming a major cause of crop yield losses worldwide. Rice (Oryza sativa) is the most salt-sensitive cereal crop, and many studies have focused on rice salinity tolerance, but a global understanding of this crop\\'s response to salinity is still lacking. We systematically analyzed phenotypic data previously collected for 56 rice genotypes to assess the extent to which rice uses three known salinity tolerance mechanisms: shoot-ion independent tolerance (or osmotic tolerance), ion exclusion, and tissue tolerance. In general, our analyses of different phenotypic traits agree with results of previous rice salinity tolerance studies. However, we also established that the three salinity tolerance mechanisms mentioned earlier appear among rice genotypes and that none of them is predominant. Against the pervasive view in the literature that the K+/Na+ ratio is the most important trait in salinity tolerance, we found that the K+ concentration was not significantly affected by salt stress in rice, which puts in question the importance of K+/Na+ when analyzing rice salt stress response. Not only do our results contribute to improve our global understanding of salt stress response in an important crop, but we also use our results together with an extensive literature research to highlight some issues commonly observed in salinity stress tolerance studies and to propose solutions for future experiments.

  20. Differences in the sensitivity to UVB radiation of two cultivars of rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Hidema, J.; Kang, H.S.; Kumagai, T.

    1996-01-01

    The effects of UVB radiation on the growth of two cultivars of Japanese lowland rice (Oryza sativa L.), Sasanishiki and Norin 1, were examined in a phytotron. Supplementation of visible radiation with UVB radiation reduced plant length, tiller number, the fresh and dry weights of the aboveground parts of plants, an the amounts of total leaf nitrogen, chlorophyll, soluble protein and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) in the eight leaf, the youngest fully expanded leaf. By contrast, UVB radiation significantly increased the accumulation of UV-absorbing compounds. There was a difference between the two cultivars in the resistance to the effects of UVB radiation. The reduction in the amounts of Rubisco was smaller in Sasanishiki, while the increase in the accumulation of UV-absorbing compounds was greater in Sasanishiki. Parameters of plant growth, with the exception of the amount of Rubisco, decreased in direct proportion to decreases in total leaf nitrogen in plants grown under lower or the Rubisco content of Norin 1 grown under a high dose of UVB radiation was exceptionally marked, and was not observed similarly in Sasanishiki. The results suggest that the remarkable reduction in rubisco content in NOrin 1 might have been due to the specific effects of UVB radiation. It is also suggested that the difference between cultivars in the resistance to UVB radiation might be due to the differences in the levels of Rubisco and in UV-absorbing compounds that are induced by UVB radiation

  1. The humic acids from vermicompost protect rice (Oryza sativa L.) plants against a posterior hidric stress

    International Nuclear Information System (INIS)

    Guridi-Izquierdo, Fernando; Martínez-Balmori, Dariellys; Rosquete-Bassó, Mayelín; Calderín-García, Andrés; Louro-Berbara, Ricardo L.

    2017-01-01

    The humic acids (HA) from two different vermicompost were extracted, isolated, purified and partially characterized, to evaluate their possible protection in rice (Oryza sativa L.) plants against an hydric stress. Differences in elemental composition, as the coagulation threshold value and E4/E6 relation in their UV-Vis spectra were found. Two concentrations (40 and 60 mg L-1) of both HA were included in the nutritive solutions for rice plants in controlled conditions. It was verified that the previous treatment with the HA during six days stimulated the root biomass production. Later the HA were excluded and was an hydric deficit induced by adding polietilenglicol (PEG-6000) in the initially treated plants and in a group of those used as control. After 96 hours of this final condition the net radical biomass, the photosynthetic pigments content and the root membrane permeability were evaluated. In the plants previously treated with HA (at the concentration 60 mg HA L-1), the root membrane permeability, the net radical biomass production and the “a” chlorophyll content had no differences when compared with those without stress. It was concluded that the previous treatment with the HA protected the rice plants against a posterior hydric stress that was induced. (author)

  2. The relationship between vacuolation and initiation of PCD in rice (Oryza sativa) aleurone cells

    Science.gov (United States)

    Zheng, Yan; Zhang, Heting; Deng, Xiaojiang; Liu, Jing; Chen, Huiping

    2017-01-01

    Vacuole fusion is a necessary process for the establishment of a large central vacuole, which is the central location of various hydrolytic enzymes and other factors involved in death at the beginning of plant programmed cell death (PCD). In our report, the fusion of vacuoles has been presented in two ways: i) small vacuoles coalesce to form larger vacuoles through membrane fusion, and ii) larger vacuoles combine with small vacuoles when small vacuoles embed into larger vacuoles. Regardless of how fusion occurs, a large central vacuole is formed in rice (Oryza sativa) aleurone cells. Along with the development of vacuolation, the rupture of the large central vacuole leads to the loss of the intact plasma membrane and the degradation of the nucleus, resulting in cell death. Stabilizing or disrupting the structure of actin filaments (AFs) inhibits or promotes the fusion of vacuoles, which delays or induces PCD. In addition, the inhibitors of the vacuolar processing enzyme (VPE) and cathepsin B (CathB) block the occurrence of the large central vacuole and delay the progression of PCD in rice aleurone layers. Overall, our findings provide further evidence for the rupture of the large central vacuole triggering the PCD in aleruone layers.

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

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    M. A. Hakim

    2014-01-01

    Full Text Available 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.

  4. QTL detection and elite alleles mining for stigma traits in Oryza sativa by association mapping

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    Xiaojing Dang

    2016-08-01

    Full Text Available Stigma traits are very important for hybrid seed production in Oryza sativa, which is a self-pollinated crop; however, the genetic mechanism controlling the traits is poorly understood. In this study, we investigated the phenotypic data of 227 accessions across two years and assessed their genotypic variation with 249 simple sequence repeat (SSR markers. By combining phenotypic and genotypic data, a genome-wide association (GWA map was generated. Large phenotypic variations in stigma length (STL, stigma brush-shaped part length (SBPL and stigma non-brush-shaped part length (SNBPL were found. Significant positive correlations were identified among stigma traits. In total, 2,072 alleles were detected among 227 accessions, with an average of 8.3 alleles per SSR locus. GWA mapping detected 6 quantitative trait loci (QTLs for the STL, 2 QTLs for the SBPL and 7 QTLs for the SNBPL. Eleven, 5, and 12 elite alleles were found for the STL, SBPL and SNBPL, respectively. Optimal cross designs were predicted for improving the target traits. The detected genetic variation in stigma traits and QTLs provides helpful information for cloning candidate STL genes and breeding rice cultivars with longer STLs in the future.

  5. Cadmium and lead content in several brands of rice grains (Oryza sativa) in central Iran.

    Science.gov (United States)

    Shakerian, A; Rahimi, E; Ahmadi, M

    2012-11-01

    The aim of this study was to investigate the cadmium (Cd) and lead (Pb) content of several commercially available brands of rice grains (Oryza sativa) in central Iran. A total of 67 samples of the most widely consumed brands of rice grains were purchased from local bazaar markets in Shahrekord, Iran. The first step, grains of raw rice were digested by acid digestion method and then were analyzed by atomic absorption spectrometer. The results showed that Cd concentration in rice grains ranged from 0.0378 to 0.1225 ppm dry weight and its average concentration was 0.062 ± 0.019 ppm and Pb content ranged from 0.0405 to 0.1281 ppm dry weight and its average concentration was 0.068 ± 0.0185 ppm. Cd and Pb concentrations in the sampled rice grains were lower in comparison with their upper limits (0.2 and 0.2 ppm for Cd and Pb, respectively) approved by food sanitary standard. Therefore, it can be concluded that there is no health problems due to the consumption of brands of rice grains, for these two elements. The results indicated that weekly intake of Cd and Pb from rice grains was below the provisional tolerable weekly intakes recommended by WHO/FAO.

  6. Influence of lead on atrazine uptake by rice (Oryza sativa L.) seedlings from nutrient solution.

    Science.gov (United States)

    Su, Yu-Hong; Zhu, Yong-Guan

    2005-01-01

    Atrazine is a widely used herbicide, and its persistence in soil and water causes environmental concerns. In the past, plant uptake processes are mainly investigated for single contaminants. However, in many cases, contaminants co-exist in environmental matrix, such as soil, and plant uptake of one contaminant may be influenced by its co-existing ones. The uptake of atrazine by rice seedlings (Oryza sativa L.) from nutrient solution through the roots was investigated in a solution culture, over an exposure period of 4 weeks. Atrazine accumulation in plant tissues was determined by gas chromatography, and lead was determined using atomic absorption spectrometry. With different ratios of atrazine and Pb2+ concentrations in solution, the observed atrazine concentrations in shoots and roots varied significantly. In atrazine-Pb2+ mixture systems, the added Pb2+ either increased or decreased the concentrations or BCFs of atrazine in seedlings (relative to those without Pb2+), depending on the atrazine-Pb2+ ratio in nutrient solution. The enhanced atrazine uptake results presumably from atrazine-Pb2+ complex formation. The reduced atrazine uptake, which occurred mainly at high atrazine concentrations, is attributed to atrazine toxicity that inhibited seedling growth and transpiration. The formation of atrazine-Pb2+ complex both in the solution and within plant tissues may affect the accumulation of both contaminants by rice plants.

  7. Comparative Mapping of Seed Dormancy Loci Between Tropical and Temperate Ecotypes of Weedy Rice (Oryza sativa L.

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    Lihua Zhang

    2017-08-01

    Full Text Available Genotypic variation at multiple loci for seed dormancy (SD contributes to plant adaptation to diverse ecosystems. Weedy rice (Oryza sativa was used as a model to address the similarity of SD genes between distinct ecotypes. A total of 12 quantitative trait loci (QTL for SD were identified in one primary and two advanced backcross (BC populations derived from a temperate ecotype of weedy rice (34.3°N Lat.. Nine (75% of the 12 loci were mapped to the same positions as those identified from a tropical ecotype of weedy rice (7.1°N Lat.. The high similarity suggested that the majority of SD genes were conserved during the ecotype differentiation. These common loci are largely those collocated/linked with the awn, hull color, pericarp color, or plant height loci. Phenotypic correlations observed in the populations support the notion that indirect selections for the wild-type morphological characteristics, together with direct selections for germination time, were major factors influencing allelic distributions of SD genes across ecotypes. Indirect selections for crop-mimic traits (e.g., plant height and flowering time could also alter allelic frequencies for some SD genes in agroecosystems. In addition, 3 of the 12 loci were collocated with segregation distortion loci, indicating that some gametophyte development genes could also influence the genetic equilibria of SD loci in hybrid populations. The SD genes with a major effect on germination across ecotypes could be used as silencing targets to develop transgene mitigation (TM strategies to reduce the risk of gene flow from genetically modified crops into weed/wild relatives.

  8. Extraction of anthocyanins and polyphenols from black rice (Oryza sativa L.) by modeling and assessing their reversibility and stability.

    Science.gov (United States)

    Pedro, Alessandra Cristina; Granato, Daniel; Rosso, Neiva Deliberali

    2016-01-15

    This study was aimed the extraction of total flavonoids, anthocyanins and phenolics, as well as the antioxidant activity of black rice (Oryza sativa) and to study the stability in relation to pH, light and copigmentation. Variations in temperature (10-50°C), time (20-80min), and solid-solvent ratio (1:15-1:45) were studied using a Box-Behnken design. The regression models were significant (Pblack rice was cyanidin-3-glucoside. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Engineering the Oryza sativa cell wall with rice NAC transcription factors regulating secondary wall formation

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    Kouki eYoshida

    2013-10-01

    Full Text Available Plant tissues that require structural rigidity synthesize a thick, strong secondary cell wall of lignin, cellulose and hemicelluloses in a complicated bridged structure. Master regulators of secondary wall synthesis were identified in dicots, and orthologs of these regulators have been identified in monocots, but regulation of secondary cell wall formation in monocots has not been extensively studied. Here we demonstrate that the rice transcription factors SECONDARY WALL NAC DOMAIN PROTEINs (SWNs can regulate secondary wall formation in rice (Oryza sativa and are potentially useful for engineering the monocot cell wall. The OsSWN1 promoter is highly active in sclerenchymatous cells of the leaf blade and less active in xylem cells. By contrast, the OsSWN2 promoter is highly active in xylem cells and less active in sclerenchymatous cells. OsSWN2 splicing variants encode two proteins; the shorter protein (OsSWN2S has very low transcriptional activation ability, but the longer protein (OsSWN2L and OsSWN1 have strong transcriptional activation ability. In rice, expression of an OsSWN2S chimeric repressor, driven by the OsSWN2 promoter, resulted in stunted growth and para-wilting (leaf rolling and browning under normal water conditions due to impaired vascular vessels. The same OsSWN2S chimeric repressor, driven by the OsSWN1 promoter, caused a reduction of cell wall thickening in sclerenchymatous cells, a drooping leaf phenotype, reduced lignin and xylose contents and increased digestibility as forage. These data suggest that OsSWNs regulate secondary wall formation in rice and manipulation of OsSWNs may enable improvements in monocotyledonous crops for forage or biofuel applications.

  10. Arsenate exposure affects amino acids, mineral nutrient status and antioxidants in rice (Oryza sativa L.) genotypes.

    Science.gov (United States)

    Dwivedi, S; Tripathi, R D; Tripathi, P; Kumar, A; Dave, R; Mishra, S; Singh, R; Sharma, D; Rai, U N; Chakrabarty, D; Trivedi, P K; Adhikari, B; Bag, M K; Dhankher, O P; Tuli, R

    2010-12-15

    Simulated pot experiments were conducted on four rice (Oryza sativa L.) genotypes (Triguna, IR-36, PNR-519, and IET-4786) to examine the effects of As(V) on amino acids and mineral nutrient status in grain along with antioxidant response to arsenic exposure. Rice genotypes responded differentially to As(V) exposure in terms of amino acids and antioxidant profiles. Total amino acid content in grains of all rice genotypes was positively correlated with arsenic accumulation. While, most of the essential amino acids increased in all cultivars except IR-36, glutamic acid and glycine increased in IET-4786 and PNR-519. The level of nonprotein thiols (NPTs) and the activities of superoxide dismutase (SOD; EC 1.15.1.1), glutathione reductase (GR; EC 1.6.4.2) and ascorbate peroxidase (APX; EC 1.11.1.11) increased in all rice cultivars except IET-4786. A significant genotypic variation was also observed in specific arsenic uptake (SAU; mg kg(-1)dw), which was in the order of Triguna (134) > IR-36 (71) > PNR-519 (53) > IET-4786 (29). Further, application of As(V) at lower doses (4 and 8 mg L(-1) As) enhanced the accumulation of selenium (Se) and other nutrients (Fe, P, Zn, and S), however, higher dose (12 mg L(-1) As) limits the nutrient uptake in rice. In conclusion, low As accumulating genotype, IET-4786, which also had significantly induced level of essential amino acids, seems suitable for cultivation in moderately As contaminated soil and would be safe for human consumption.

  11. Improvement of nitrogen accumulation and metabolism in rice (Oryza sativa L.) by the endophyte Phomopsis liquidambari.

    Science.gov (United States)

    Yang, Bo; Ma, Hai-Yan; Wang, Xiao-Mi; Jia, Yong; Hu, Jing; Li, Xia; Dai, Chuan-Chao

    2014-09-01

    The fungal endophyte Phomopsis liquidambari can enhance nitrogen (N) uptake and metabolism of rice plants under hydroponic conditions. To investigate the effects of P. liquidambari on N accumulation and metabolism in rice (Oryza sativa L.) under field conditions during the entire growing season (S1, the seedling stage; S2, the tillering stage; S3, the heading stage; S4, the ripening stage), we utilized pot experiments to examine metabolic and physiological levels in both shoot and root tissues of rice, with endophyte (E+) and without endophyte (E-), in response to three different N levels. We found that under low-N treatment, P. liquidambari symbiosis increased the rice yield and N use efficiency by 12% and by 11.59%, respectively; that the total N contents in E+ rice plants at the four growth stages were separately increased by 29.05%, 14.65%, 21.06% and 18.38%, respectively; and that the activities of nitrate reductase and glutamine synthetase in E+ rice roots and shoots were significantly increased by fungal infection during the S1 to S3 stages. Moreover, P. liquidambari significantly increased the free NH4(+), NO3(-), amino acid and soluble protein contents in infected rice tissues under low-N treatment during the S1 to S3 stages. The obtained results offer novel data concerning the systemic changes induced by P. liquidambari in rice during the entire growth period and confirm the hypothesis that the rice-P. liquidambari interaction improved the N accumulation and metabolism of rice plants, consequently increasing rice N utilization in nutrient-limited soil. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  12. Effect of selenium application on arsenic uptake in rice (Oryza sativa L.).

    Science.gov (United States)

    Kaur, Sumandeep; Singh, Dhanwinder; Singh, Kuldip

    2017-09-01

    Alluvial aquifers of the agrarian state of Punjab of southwestern arid zone used for irrigation of rice crops are rich in arsenic concentration. In the present study, rice (Oryza sativa L.) crops were raised in pots in a greenhouse with a purpose to study whether selenium (Se) application was effective in ameliorating As uptake. The rice crop was irrigated with arsenic laced water (0, 2.5, 5.0, 10.0 μM As L -1 ) throughout the growing period, without and with selenium (0.05 and 0.10 mg kg -1 ) added through mustard biomass, grown ex situ in seleniferous soil. Arsenic uptake and dry matter yield in different parts of the rice crop were assayed after application of As alone and simultaneous supplementations (As + Se). An antagonistic interaction between Se and As was observed. Addition of As through irrigation water significantly reduced yield of rice grain, straw and root. However, subsequent addition of Se helped in mitigating the harmful effect of As and countered the yield reduction caused due to As toxicity. The effect of Se on dry matter yield was more pronounced at its higher dose (0.10 mg kg -1 ) as compared to its lower dose (0.05 mg kg -1 ). The presence of Se either alone or added along with As significantly reduced the As concentration and its uptake by different parts of rice and higher reduction in As concentration was observed with addition of the highest level of applied Se (0.10 mg kg -1 ). Our observations indicated that Se supplementation might be favourable to reduce As accumulation and toxicity in rice crops.

  13. 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

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

    Directory of Open Access Journals (Sweden)

    Md. Kamal Uddin

    2012-04-01

    Full Text Available 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, ∆5-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.

  15. The influence of soil water status on Oryza Sativa Var. MR220 in KADA rice agroecosystem

    International Nuclear Information System (INIS)

    Nashriyah Mat; Ismail Che Haron; Mazleha Maskin; Mohd Razi Ismail

    2006-01-01

    A study to determine the influence of soil water status on rice plant Oryza sativa var. MR220 after panicle initiation stage was carried out at Ladang Merdeka Mulong Lating in the Kemubu Agricultural Development Authority (KADA) area, Kelantan. Five water management treatments imposed on direct seeded rice were; T1. Continuous flooding, T2. Early flooding up to panicle initiation stage followed by saturated (F55-saturated), T3. Early flooding for the first month followed by saturated (F-30 saturated), T4. Continuous saturated, and T5. Continuous field capacity condition throughout the growth stage. The treatments were arranged in Randomized Complete Block Design (RCBD) with four replicates. Results showed significant differences in soil moisture content in the order of T1>T2>T3>T4>T5. Significant differences were also observed in rice plant water content at 68 DAS (days after seeding) in the order of T2>T3>T4>T1>T5. Moisture content also showed significant differences between replicates in the order of R1>R2>R3>R4 and R2>R1>R3>R4; in rice plant and ricefield soil, respectively. Results however showed no significant difference in leaf stomatal conductance due to water stress. Rice plant moisture, soil moisture and leaf stomatal conductance showed no interaction. Published results show that even though overall crop yield was reduced by sheath blight and panicle blast incidence that occur at later stage in 2004-2005 field trials, highest grain yields were obtained from T2 (off season) and T4 (main season). Saturated condition seems to be the most suitable method of growing rice under minimal water input in KADA rice agroecosystem. (Author)

  16. Changes in gene expression and catalase activity in Oryza sativa L. under abiotic stress.

    Science.gov (United States)

    Vighi, I L; Benitez, L C; do Amaral, M N; Auler, P A; Moraes, G P; Rodrigues, G S; da Maia, L C; Pinto, L S; Braga, E J B

    2016-11-03

    Different rice (Oryza sativa L.) genotypes were subjected to high salinity and low temperature (150 mM NaCl and 13°C, respectively) for 0, 6, 24, 48, or 72 h. We evaluated the simultaneous expression of the genes OsCATA, OsCATB, and OsCATC, correlated gene expression with enzyme activity, and verified the regulation of these genes through identification of cis-elements in the promoter region. The hydrogen peroxide content increased in a tolerant genotype and decreased in a sensitive genotype under both stress conditions. Lipid peroxidation increased in the tolerant genotype when exposed to cold, and in the sensitive genotype when exposed to high salinity. Catalase activity significantly increased in both genotypes when subjected to 13°C. In the tolerant genotype, OsCATA and OsCATB were the most responsive to high salinity and cold, while in the sensitive genotype, OsCATA and OsCATC responded positively to saline stress, as did OsCATA and OsCATB to low temperature. Cis-element analysis identified different regulatory sequences in the catalase promoter region of each genotype. The sensitive genotype maintained a better balance between hydrogen oxyacid levels, catalase activity, and lipid peroxidation under low temperature than the resistant genotype. OsCATA and OsCATB were the most responsive in the salt-tolerant genotype to cold, OsCATA and OsCATC were the most responsive to saline stress, and OsCATA and OsCATB were the most responsive to chilling stress in the sensitive genotype. There were positive correlations between catalase activity and OsCATB expression in the tolerant genotype under saline stress and in the sensitive genotype under cold stress.

  17. PENETAPAN KADAR FENOLIK TOTAL DAN FLAVONOID TOTAL EKSTRAK BERAS HITAM (Oryza sativa L DARI KALIMANTAN SELATAN

    Directory of Open Access Journals (Sweden)

    Anna Khumaira Sari

    2017-10-01

    Full Text Available The black rice contains anthocyanin compounds which are included in the flavonoids and phenolic compounds. Flavonoids contained in black rice are phenolic components that act as a preventive of hydroxyl and superoxide radicals by protecting membrane lipids against damaging oxidation reactions and phenol compounds also have bacteriocid, antimetic, antihelmintic, antiinflammatory, antimicrobial, anticancer and other degenerative diseases. The aim of this research were to measure total phenolic content and total flavonoid in ethanol extract of black rice (Oryza sativa L. Total phenol content were measured by Folin-Ciocalteu method with gallic acid mean while total flavonoid content were measured by colorimetry method using reagent AlCl3 10% and 5% acetic acid. There are seven variation samples of black rice obtained from seven different places in South Kalimantan. The result of this study, qualitative analysis showed that all samples positive contained flavonoids, alkaloids and tannins. The total phenol content of the seven samples was 100,58 ± 1,344; 91.14 ± 1.699; 96.50 ± 1.529; 77.64 ± 0.462; 81,16 ± 0,614; 112.47 ± 1.040; 81,50 ± 2,928 mgGAE/mg extract and the percent of total flavonoid content from seven samples was 8,53 ± 0,208%; 8.11 ± 0.343%; 7.69 ± 0.446%; 6.03 ± 0.227%; 4.97 ± 0.169%; 3.74 ± 0.210%; 5.02 ± 0.403%.

  18. The response of rice (Oryza sativa L. to elevated night temperature with application of Pyraclostobin

    Directory of Open Access Journals (Sweden)

    T.Y. Wahjanto

    2016-07-01

    Full Text Available Rice productivity is having a problem related with climate change phenomenon, mainly the global warming. The rising of temperature in some country threat the rice production. The increasing of temperature is a major limiting factor that affects yield through the growth and development of rice plant. This study was aimed to examine the response of rice (Oryza sativa L. to elevated night temperature with the application of Pyraclostobin. A glasshouse experiment that was conducted from March to August 2015 at Brawijaya University Research Station of Jatikerto – Malang, used nested plot design with three replications and two treatments. The first treatments were the night temperature level (normal temperature, increased 2oC, and increased 4oC. The second treatments were the concentration of Pyraclostrobin (0 ppm, 400 ppm and 800 ppm. Results of the study showed that the increase of temperature at night for about 2oC and 4oC, as well as application of Pyraclostrobin, affected growth and yield of rice. Application of Pyraclostrobin by concentrations of 400 ppm and 800 ppm effectively reduced yield loss by increasing night temperature of 2oC, which resulted in 20.20% and 24.93%, respectively, in comparison with the control; while the increase of night temperature by 4oC have resulted 26.86% and 33.33% in comparison with the control. Pyraclostrobin was effective in maintaining percentage of the filled spikelets by the increase of temperature at night for about 2oC and 4oC.

  19. Hybrid Sterility in Rice (Oryza sativa L.) Involves the Tetratricopeptide Repeat Domain Containing Protein.

    Science.gov (United States)

    Yu, Yang; Zhao, Zhigang; Shi, Yanrong; Tian, Hua; Liu, Linglong; Bian, Xiaofeng; Xu, Yang; Zheng, Xiaoming; Gan, Lu; Shen, Yumin; Wang, Chaolong; Yu, Xiaowen; Wang, Chunming; Zhang, Xin; Guo, Xiuping; Wang, Jiulin; Ikehashi, Hiroshi; Jiang, Ling; Wan, Jianmin

    2016-07-01

    Intersubspecific hybrid sterility is a common form of reproductive isolation in rice (Oryza sativa L.), which significantly hampers the utilization of heterosis between indica and japonica varieties. Here, we elucidated the mechanism of S7, which specially causes Aus-japonica/indica hybrid female sterility, through cytological and genetic analysis, map-based cloning, and transformation experiments. Abnormal positioning of polar nuclei and smaller embryo sac were observed in F1 compared with male and female parents. Female gametes carrying S7(cp) and S7(i) were aborted in S7(ai)/S7(cp) and S7(ai)/S7(i), respectively, whereas they were normal in both N22 and Dular possessing a neutral allele, S7(n) S7 was fine mapped to a 139-kb region in the centromere region on chromosome 7, where the recombination was remarkably suppressed due to aggregation of retrotransposons. Among 16 putative open reading frames (ORFs) localized in the mapping region, ORF3 encoding a tetratricopeptide repeat domain containing protein was highly expressed in the pistil. Transformation experiments demonstrated that ORF3 is the candidate gene: downregulated expression of ORF3 restored spikelet fertility and eliminated absolutely preferential transmission of S7(ai) in heterozygote S7(ai)/S7(cp); sterility occurred in the transformants Cpslo17-S7(ai) Our results may provide implications for overcoming hybrid embryo sac sterility in intersubspecific hybrid rice and utilization of hybrid heterosis for cultivated rice improvement. Copyright © 2016 by the Genetics Society of America.

  20. Alternate wetting and drying decreases methylmercury in flooded rice (Oryza sativa) systems

    Science.gov (United States)

    Tanner, K. Christy; Windham-Myers, Lisamarie; Marvin-DiPasquale, Mark C.; Fleck, Jacob; Linquist, Bruce A.

    2018-01-01

    In flooded soils, including those found in rice (Oryza sativa L.) fields, microbes convert inorganic Hg to more toxic methylmercury (MeHg). Methylmercury is accumulated in rice grain, potentially affecting health. Methylmercury in rice field surface water can bioaccumulate in wildlife. We evaluated how introducing aerobic periods into an otherwise continuously flooded rice growing season affects MeHg dynamics. Conventional continuously flooded (CF) rice field water management was compared with alternate wetting and drying, where irrigation was stopped twice during the growing season, allowing soil to dry to 35% volumetric moisture content, at which point plots were reflooded (AWD-35). Methylmercury studies began at harvest in Year 3 and throughout Year 4 of a 4-yr replicated field experiment. Bulk soil, water, and plant samples were analyzed for MeHg and total Hg (THg), and iron (Fe) speciation was measured in soil samples. Rice grain yield over 4 yr did not differ between treatments. Soil chemistry responded quickly to AWD-35 dry-downs, showing significant oxidation of Fe(II) accompanied by a significant reduction of MeHg concentration (76% reduction at harvest) compared with CF. Surface water MeHg decreased by 68 and 39% in the growing and fallow seasons, respectively, suggesting that the effects of AWD-35 management can last through to the fallow season. The AWD-35 treatment reduced rice grain MeHg and THg by 60 and 32%, respectively. These results suggest that the more aerobic conditions caused by AWD-35 limited the activity of Hg(II)-methylating microbes and may be an effective way to reduce MeHg concentrations in rice ecosystems.

  1. Phytoextraction of cadmium by rice (Oryza sativa L.), soybean (Glycine max (L.) Merr.), and maize (Zea mays L.)

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, M. [Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan)]. E-mail: simple@affrc.go.jp; Ae, N. [Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan)]. E-mail: aenoriha@kobe-u.ac.jp; Ishikawa, S. [Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan)]. E-mail: isatoru@niaes.affrc.go.jp

    2007-01-15

    Selecting a phytoextraction plant with high Cd-accumulating ability based on the plant's compatibility with mechanized cultivation techniques may yield more immediately practical results than selection based on high tolerance to Cd. Rice (Oryza sativa L., cv. Nipponbare and Milyang 23), soybean (Glycine max [L.] Merr., cv. Enrei and Suzuyutaka), and maize (Zea mays L., cv. Gold Dent) were grown on one Andosol and two Fluvisols with low concentration of Cd contamination ranging from 0.83 to 4.29 mg Cd kg{sup -1}, during 60 days in pots (550 mL) placed in a greenhouse. Shoot Cd uptake was as follows: Gold Dent < Enrei and Nipponbare < Suzuyutaka and Milyang 23. Several soil Cd fractions after Milyang 23 harvesting decreased most. Milyang 23 accumulated 10-15% of the total soil Cd in its shoot. The Milyang 23 rice is thus promising for phytoextraction of Cd from paddy soils with low contamination level. - Milyang 23 rice (Oryza sativa L.) accumulated 10-15% of the total soil Cd in its shoot.

  2. Phytoextraction of cadmium by rice (Oryza sativa L.), soybean (Glycine max (L.) Merr.), and maize (Zea mays L.)

    International Nuclear Information System (INIS)

    Murakami, M.; Ae, N.; Ishikawa, S.

    2007-01-01

    Selecting a phytoextraction plant with high Cd-accumulating ability based on the plant's compatibility with mechanized cultivation techniques may yield more immediately practical results than selection based on high tolerance to Cd. Rice (Oryza sativa L., cv. Nipponbare and Milyang 23), soybean (Glycine max [L.] Merr., cv. Enrei and Suzuyutaka), and maize (Zea mays L., cv. Gold Dent) were grown on one Andosol and two Fluvisols with low concentration of Cd contamination ranging from 0.83 to 4.29 mg Cd kg -1 , during 60 days in pots (550 mL) placed in a greenhouse. Shoot Cd uptake was as follows: Gold Dent < Enrei and Nipponbare < Suzuyutaka and Milyang 23. Several soil Cd fractions after Milyang 23 harvesting decreased most. Milyang 23 accumulated 10-15% of the total soil Cd in its shoot. The Milyang 23 rice is thus promising for phytoextraction of Cd from paddy soils with low contamination level. - Milyang 23 rice (Oryza sativa L.) accumulated 10-15% of the total soil Cd in its shoot

  3. Oryza sativa Chloroplast Signal Recognition Particle 43 (OscpSRP43 Is Required for Chloroplast Development and Photosynthesis.

    Directory of Open Access Journals (Sweden)

    Xiang-guang Lv

    Full Text Available A rice chlorophyll-deficient mutant w67 was isolated from an ethyl methane sulfonate (EMS-induced IR64 (Oryza sativa L. ssp. indica mutant bank. The mutant exhibited a distinct yellow-green leaf phenotype in the whole plant growth duration with significantly reduced levels of chlorophyll and carotenoid, impaired chloroplast development and lowered capacity of photosynthesis compared with the wild-type IR64. Expression of a number of genes associated with chlorophyll metabolism, chloroplast biogenesis and photosynthesis was significantly altered in the mutant. Genetic analysis indicated that the yellow-green phenotype was controlled by a single recessive nuclear gene located on the short arm of chromosome 3. Using map-based strategy, the mutation was isolated and predicted to encode a chloroplast signal recognition particle 43 KD protein (cpSRP43 with 388 amino acid residuals. A single base substitution from A to T at position 160 resulted in a premature stop codon. OscpSRP43 was constitutively expressed in various organs with the highest level in the leaf. Functional complementation could rescue the mutant phenotype and subcellular localization showed that the cpSRP43:GFP fusion protein was targeted to the chloroplast. The data suggested that Oryza sativa cpSRP43 (OscpSRP43 was required for the normal development of chloroplasts and photosynthesis in rice.

  4. Control of gibberellin A(l) levels by 2, beta-hydroxylation during growth of dwarf Oryza sativa L. var. Tan-ginbozu

    International Nuclear Information System (INIS)

    Railton, I.D.

    1978-01-01

    Seedlings of dwarf rice (Oryza sativa L. var. Tan-ginbozu) exhibit a marked growth response to applied gibberellin A(1) and convert this compound into gibberellin A(8). In this study attempts were made to correlate the metabolism of 1,2[ 3 H] gibberellin A(1) and in particular the production of gibberellin A(8) with rice leaf sheath growth

  5. Molecular cloning, functional characterization and expression analysis of a novel monosaccharide transporter gene OsMST6 from rice (Oryza sativa L.)

    NARCIS (Netherlands)

    Wang, Y.; Xiao, Y.; Zhang, Y.; Chai, C.; Wei, G.; Wei, X.; Xu, H.; Wang, M.; Ouwerkerk, P.B.F.; Zhu, Z.

    2008-01-01

    Monosaccharides transporters play important roles in assimilate supply for sink tissue development. In this study, a new monosaccharide transporter gene OsMST6 was identified from rice (Oryza sativa L.). The predicted OsMST6 protein shows typical features of sugar transporters and shares 79.6%

  6. Fine mapping and introgressing qFIS1-2, a major QTL for kernel fissure resistance in rice (Oryza sativa L.)

    Science.gov (United States)

    Rice (Oryza sativa L.) kernel fissuring increases breakage during milling and decreases the value of processed rice. This study employed molecular gene tagging methods to fine-map a fissure resistance (FR) locus in ‘Cybonnet’, a semidwarf tropical japonica cultivar, as well as transfer this trait to...

  7. The Population Structure of African Cultivated Rice Oryza glaberrima (Steud.)

    DEFF Research Database (Denmark)

    Semon, Mande; Nielsen, Rasmus; Jones, Monty P.

    2005-01-01

    Genome-wide linkage disequilibrium (LD) was investigated for 198 accessions of Oryza glaberrima using 93 nuclear microsatellite markers. Significantly elevated levels of LD were detected, even among distantly located markers. Free recombination among loci at the population genetic level was shown...

  8. Quantitative Genetic Analysis for Yield and Yield Components in Boro Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Supriyo CHAKRABORTY

    2010-03-01

    Full Text Available Twenty-nine genotypes of boro rice (Oryza sativa L. were grown in a randomized block design with three replications in plots of 4m x 1m with a crop geometry of 20 cm x 20 cm between November-April, in Regional Agricultural Research Station, Nagaon, India. Quantitative data were collected on five randomly selected plants of each genotype per replication for yield/plant, and six other yield components, namely plant height, panicles/plant, panicle length, effective grains/panicle, 100 grain weight and harvest index. Mean values of the characters for each genotype were used for analysis of variance and covariance to obtain information on genotypic and phenotypic correlation along with coheritability between two characters. Path analyses were carried out to estimate the direct and indirect effects of boro rice�s yield components. The objective of the study was to identify the characters that mostly influence the yield for increasing boro rice productivity through breeding program. Correlation analysis revealed significant positive genotypic correlation of yield/plant with plant height (0.21, panicles/plant (0.53, panicle length (0.53, effective grains/panicle (0.57 and harvest index (0.86. Path analysis based on genotypic correlation coefficients elucidated high positive direct effect of harvest index (0.8631, panicle length (0.2560 and 100 grain weight (0.1632 on yield/plant with a residual effect of 0.33. Plant height and panicles/plant recorded high positive indirect effect on yield/plant via harvest index whereas effective grains/panicle on yield/plant via harvest index and panicle length. Results of the present study suggested that five component characters, namely harvest index, effective grains/plant, panicle length, panicles/plant and plant height influenced the yield of boro rice. A genotype with higher magnitude of these component characters could be either selected from the existing genotypes or evolved by breeding program for genetic

  9. Analysis of transactivation potential of rice (Oryza sativa L.) heat shock factors.

    Science.gov (United States)

    Lavania, Dhruv; Dhingra, Anuradha; Grover, Anil

    2018-06-01

    Based on yeast one-hybrid assays, we show that the presence of C-terminal AHA motifs is not a prerequisite for transactivation potential in rice heat shock factors. Transcriptional activation or transactivation (TA) of heat stress responsive genes takes place by binding of heat shock factors (Hsfs) to heat shock elements. Analysis of TA potential of thirteen rice (Oryza sativa L.) Hsfs (OsHsfs) carried out in this study by yeast one-hybrid assay showed that OsHsfsA3 possesses strong TA potential while OsHsfs A1a, A2a, A2b, A4a, A4d, A5, A7b, B1, B2a, B2b, B2c and B4d lack TA potential. From a near complete picture of TA potential of the OsHsf family (comprising of 25 members) emerging from this study and an earlier report from our group (Mittal et al. in FEBS J 278(17):3076-3085, 2011), it is concluded that (1) overall, six OsHsfs, namely A3, A6a, A6b, A8, C1a and C1b possess TA potential; (2) four class A OsHsfs, namely A3, A6a, A6b and A8 have TA potential out of which A6a and A6b contain AHA motifs while A3 and A8 lack AHA motifs; (3) nine class A OsHsfs, namely A1a, A2a, A2b, A2e, A4a, A4d, A5, A7a and A7b containing AHA motif(s) lack TA function in the yeast assay system; (4) all class B OsHsfs lack AHA motifs and TA potential (B4a not analyzed) and (5) though all class C OsHsf members lack AHA motifs, two members C1a and C1b possess TA function, while one member C2a lacks TA potential (C2b not analyzed). Thus, the presence or absence of AHA motif is possibly not the only factor determining TA potential of OsHsfs. Our findings will help to identify the transcriptional activators of rice heat shock response.

  10. Effects of silicon on Oryza sativa L. seedling roots under simulated acid rain stress.

    Science.gov (United States)

    Ju, Shuming; Yin, Ningning; Wang, Liping; Zhang, Cuiying; Wang, Yukun

    2017-01-01

    Silicon (Si) has an important function in reducing the damage of environmental stress on plants. Acid rain is a serious abiotic stress factor, and Si can alleviate the stress induced by acid rain on plants. Based on these assumptions, we investigated the effects of silicon on the growth, root phenotype, mineral element contents, hydrogen peroxide (H2O2) and antioxidative enzymes of rice (Oryza sativa L.) seedling roots under simulated acid rain (SAR) stress. The results showed that the combined or single effects of Si and/or SAR on rice roots depend on the concentration of Si and the pH of the SAR. The combined or single effects of a low or moderate concentration of Si (1.0 or 2.0 mM) and light SAR (pH 4.0) enhanced the growth of rice roots, and the combined effects were stronger than those of the single treatment. A high concentration of Si (4.0 mM) or severe SAR (pH 2.0) exerted deleterious effects. The incorporation of Si (1.0, 2.0 or 4.0 mM) into SAR with pH 3.0 or 2.0 promoted the rice root growth, decreased the H2O2 content, increased the Si concentration and the superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) activities, maintained the balance of mineral element (K, Ca, Mg, Fe, Zn, and Cu) concentrations in the roots of rice seedlings compared with SAR alone. The alleviatory effects observed with a moderate concentration of Si (2.0 mM) were better than the effects obtained with a low or high concentration of Si (1.0 or 4.0 mM). The observed effects were due to disruptions in the absorption and utilization of mineral nutrients and impacts on the activity of antioxidant enzymes in roots, and this conclusion suggests that the degree of rice root damage caused by acid rain might be attributed to not only acid rain but also the level of Si in the soil.

  11. Effects of silicon on Oryza sativa L. seedling roots under simulated acid rain stress

    Science.gov (United States)

    Wang, Liping; Zhang, Cuiying; Wang, Yukun

    2017-01-01

    Silicon (Si) has an important function in reducing the damage of environmental stress on plants. Acid rain is a serious abiotic stress factor, and Si can alleviate the stress induced by acid rain on plants. Based on these assumptions, we investigated the effects of silicon on the growth, root phenotype, mineral element contents, hydrogen peroxide (H2O2) and antioxidative enzymes of rice (Oryza sativa L.) seedling roots under simulated acid rain (SAR) stress. The results showed that the combined or single effects of Si and/or SAR on rice roots depend on the concentration of Si and the pH of the SAR. The combined or single effects of a low or moderate concentration of Si (1.0 or 2.0 mM) and light SAR (pH 4.0) enhanced the growth of rice roots, and the combined effects were stronger than those of the single treatment. A high concentration of Si (4.0 mM) or severe SAR (pH 2.0) exerted deleterious effects. The incorporation of Si (1.0, 2.0 or 4.0 mM) into SAR with pH 3.0 or 2.0 promoted the rice root growth, decreased the H2O2 content, increased the Si concentration and the superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) activities, maintained the balance of mineral element (K, Ca, Mg, Fe, Zn, and Cu) concentrations in the roots of rice seedlings compared with SAR alone. The alleviatory effects observed with a moderate concentration of Si (2.0 mM) were better than the effects obtained with a low or high concentration of Si (1.0 or 4.0 mM). The observed effects were due to disruptions in the absorption and utilization of mineral nutrients and impacts on the activity of antioxidant enzymes in roots, and this conclusion suggests that the degree of rice root damage caused by acid rain might be attributed to not only acid rain but also the level of Si in the soil. PMID:28291806

  12. Common and distinct organ and stress responsive transcriptomic patterns in Oryza sativa and Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Castleden Ian

    2010-11-01

    Full Text Available Abstract Background Arabidopsis thaliana is clearly established as the model plant species. Given the ever-growing demand for food, there is a need to translate the knowledge learned in Arabidopsis to agronomically important species, such as rice (Oryza sativa. To gain a comparative insight into the similarities and differences into how organs are built and how plants respond to stress, the transcriptomes of Arabidopsis and rice were compared at the level of gene orthology and functional categorisation. Results Organ specific transcripts in rice and Arabidopsis display less overlap in terms of gene orthology compared to the orthology observed between both genomes. Although greater overlap in terms of functional classification was observed between root specific transcripts in rice and Arabidopsis, this did not extend to flower, leaf or seed specific transcripts. In contrast, the overall abiotic stress response transcriptome displayed a significantly greater overlap in terms of gene orthology compared to the orthology observed between both genomes. However, ~50% or less of these orthologues responded in a similar manner in both species. In fact, under cold and heat treatments as many or more orthologous genes responded in an opposite manner or were unchanged in one species compared to the other. Examples of transcripts that responded oppositely include several genes encoding proteins involved in stress and redox responses and non-symbiotic hemoglobins that play central roles in stress signalling pathways. The differences observed in the abiotic transcriptomes were mirrored in the presence of cis-acting regulatory elements in the promoter regions of stress responsive genes and the transcription factors that potentially bind these regulatory elements. Thus, both the abiotic transcriptome and its regulation differ between rice and Arabidopsis. Conclusions These results reveal significant divergence between Arabidopsis and rice, in terms of the

  13. Determination of residues of imazapic and imazaphic in rice (Oryza sativa) by HPLC

    International Nuclear Information System (INIS)

    Silva Trejos, Paulina

    2005-01-01

    A requirement to introduce a pesticide in the harvest of any product for the human consume is imperative to determine that it will not leave residues that can injure the human healthy. In this research the residues of imazapic and imazapyr, both systemic herbicides of the imidazolinone family, were determined in rice (Oryza sativa) by extraction of the samples with the extraction solvent prepared by mixing 40 mL of HC1 1 N, 2400 mL of methanol pesticide grade and 1560 mL of bidistilled water. An aliquot of the extract was concentrated approximately to 10 mL in a rotary evaporator; water was added to the concentrated extract and dissolution to 10 % m/v of lead acetate and it was regulated the pH to 6,2 with dissolution of NaOH 1 N. This dissolution was centrifuged and from the floating liquid and aliquot was measured to regulate the pH to 2,1 with dissolution of HC1 1 N. After it was extracted with dichlormethan and the join extracts were carried to dryness in the rotary evaporator. The residues were dissolved in ultrapure water of pH 2,5 and they were injected in HPLC chromatograph with a C 8 column. The validation of the analytical method obtained were: 5,1 x 10 -2 to 5,1 x 10 -3 μg/mL for linearity; (1,5 x 10 -3 , 5,0 x 10 -3 , 7,8 x 10 -3 , 2,6 x 10 -2 ) μg/mL for imazapyr and imazapic for the detection and quantification limits equivalent to 5,0 x 10 -2 mg/kg in rice; the percent of recovery were 80 % and 125 %, for imazapyr and imazapic and finally, the precision for the retention time, the area and for concentration were: 0,003 % standard deviations, 18 500 and 0,008, respectively. (author) [es

  14. Genomic selection and association mapping in rice (Oryza sativa): effect of trait genetic architecture, training population composition, marker number and statistical model on accuracy of rice genomic selection in elite, tropical rice breeding lines.

    Science.gov (United States)

    Spindel, Jennifer; Begum, Hasina; Akdemir, Deniz; Virk, Parminder; Collard, Bertrand; Redoña, Edilberto; Atlin, Gary; Jannink, Jean-Luc; McCouch, Susan R

    2015-02-01

    Genomic Selection (GS) is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its efficacy for breeding inbred lines of rice. We performed a genome-wide association study (GWAS) in conjunction with five-fold GS cross-validation on a population of 363 elite breeding lines from the International Rice Research Institute's (IRRI) irrigated rice breeding program and herein report the GS results. The population was genotyped with 73,147 markers using genotyping-by-sequencing. The training population, statistical method used to build the GS model, number of markers, and trait were varied to determine their effect on prediction accuracy. For all three traits, genomic prediction models outperformed prediction based on pedigree records alone. Prediction accuracies ranged from 0.31 and 0.34 for grain yield and plant height to 0.63 for flowering time. Analyses using subsets of the full marker set suggest that using one marker every 0.2 cM is sufficient for genomic selection in this collection of rice breeding materials. RR-BLUP was the best performing statistical method for grain yield where no large effect QTL were detected by GWAS, while for flowering time, where a single very large effect QTL was detected, the non-GS multiple linear regression method outperformed GS models. For plant height, in which four mid-sized QTL were identified by GWAS, random forest produced the most consistently accurate GS models. Our results suggest that GS, informed by GWAS interpretations of genetic architecture and population structure, could become an effective tool for increasing the efficiency of rice breeding as the costs of genotyping continue to decline.

  15. Genomic selection and association mapping in rice (Oryza sativa: effect of trait genetic architecture, training population composition, marker number and statistical model on accuracy of rice genomic selection in elite, tropical rice breeding lines.

    Directory of Open Access Journals (Sweden)

    Jennifer Spindel

    2015-02-01

    Full Text Available Genomic Selection (GS is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its efficacy for breeding inbred lines of rice. We performed a genome-wide association study (GWAS in conjunction with five-fold GS cross-validation on a population of 363 elite breeding lines from the International Rice Research Institute's (IRRI irrigated rice breeding program and herein report the GS results. The population was genotyped with 73,147 markers using genotyping-by-sequencing. The training population, statistical method used to build the GS model, number of markers, and trait were varied to determine their effect on prediction accuracy. For all three traits, genomic prediction models outperformed prediction based on pedigree records alone. Prediction accuracies ranged from 0.31 and 0.34 for grain yield and plant height to 0.63 for flowering time. Analyses using subsets of the full marker set suggest that using one marker every 0.2 cM is sufficient for genomic selection in this collection of rice breeding materials. RR-BLUP was the best performing statistical method for grain yield where no large effect QTL were detected by GWAS, while for flowering time, where a single very large effect QTL was detected, the non-GS multiple linear regression method outperformed GS models. For plant height, in which four mid-sized QTL were identified by GWAS, random forest produced the most consistently accurate GS models. Our results suggest that GS, informed by GWAS interpretations of genetic architecture and population structure, could become an effective tool for increasing the efficiency of rice breeding as the costs of genotyping continue to decline.

  16. Genomic Selection and Association Mapping in Rice (Oryza sativa): Effect of Trait Genetic Architecture, Training Population Composition, Marker Number and Statistical Model on Accuracy of Rice Genomic Selection in Elite, Tropical Rice Breeding Lines

    Science.gov (United States)

    Spindel, Jennifer; Begum, Hasina; Akdemir, Deniz; Virk, Parminder; Collard, Bertrand; Redoña, Edilberto; Atlin, Gary; Jannink, Jean-Luc; McCouch, Susan R.

    2015-01-01

    Genomic Selection (GS) is a new breeding method in which genome-wide markers are used to predict the breeding value of individuals in a breeding population. GS has been shown to improve breeding efficiency in dairy cattle and several crop plant species, and here we evaluate for the first time its efficacy for breeding inbred lines of rice. We performed a genome-wide association study (GWAS) in conjunction with five-fold GS cross-validation on a population of 363 elite breeding lines from the International Rice Research Institute's (IRRI) irrigated rice breeding program and herein report the GS results. The population was genotyped with 73,147 markers using genotyping-by-sequencing. The training population, statistical method used to build the GS model, number of markers, and trait were varied to determine their effect on prediction accuracy. For all three traits, genomic prediction models outperformed prediction based on pedigree records alone. Prediction accuracies ranged from 0.31 and 0.34 for grain yield and plant height to 0.63 for flowering time. Analyses using subsets of the full marker set suggest that using one marker every 0.2 cM is sufficient for genomic selection in this collection of rice breeding materials. RR-BLUP was the best performing statistical method for grain yield where no large effect QTL were detected by GWAS, while for flowering time, where a single very large effect QTL was detected, the non-GS multiple linear regression method outperformed GS models. For plant height, in which four mid-sized QTL were identified by GWAS, random forest produced the most consistently accurate GS models. Our results suggest that GS, informed by GWAS interpretations of genetic architecture and population structure, could become an effective tool for increasing the efficiency of rice breeding as the costs of genotyping continue to decline. PMID:25689273

  17. Effect of gamma-irradiated sludge on the growth and yield of rice (Oryza sativa L. var. GR-3)

    International Nuclear Information System (INIS)

    Pandya, G.A.; Prakash, L.; Devasia, Preston; Modi, V.V.

    1988-01-01

    The effects of gamma-irradiated sludge on the growth and yield of rice (Oryza sativa L. var. GR-3) in pot cultures have been studied. Compared to plants grown only in soil, shoot length, root length, fresh weight, dry weight, total proteins, total soluble sugars, starch and chlorophyll content of plants grown in soil supplemented with unirradiated or gamma-irradiated sludge were found to be significantly increased. Irradiation of sludge significantly stimulated the linear growth of shoot and root systems as well as fresh and dry weights of plants, compared to those grown in soil containing unirradiated sludge. There was also an improvement in the grain yield (weight of seed) when plants were grown in soil supplemented with irradiated sludge. The results obtained suggest that the gamma-irradiated sewage sludge can be beneficially recycled for agricultural uses. (author)

  18. Gamma ray, EMS and sodium azide induced effectiveness and efficiency of chlorophyll mutations in basmati rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Singh, Sanjeev; Singh, J.; Singh, R.K.

    2001-01-01

    The effectiveness and efficiency of gamma ray, EMS, sodium azide alone or in combination in relation to chlorophyll mutations in two varieties of Basmati rice (Oryza sativa L.) in M 2 generation were studied. The chlorophyll mutations were induced by all the doses of mutagens alone or in combination relatively at a fair frequency in both the varieties in M 2 generation. In general, it was found that combination treatments of gamma rays and EMS were observed to be more efficient in Taraori Basmati, while EMS alone and combination treatment of gamma rays and EMS were more efficient in Pusa Basmati 1 on sterility and growth injury basis both. Sodium azide at 0.5 mM was found as the most effective dose in both Taraori Basmati and Pusa Basmati 1 cultivars. (author)

  19. The Role of Node Restriction on Cadmium Accumulation in the Brown Rice of 12 Chinese Rice (Oryza sativa L.) Cultivars.

    Science.gov (United States)

    Huang, Gaoxiang; Ding, Changfeng; Guo, Fuyu; Li, Xiaogang; Zhou, Zhigao; Zhang, Taolin; Wang, Xingxiang

    2017-11-29

    For selection or breeding of rice (Oryza sativa L.) cultivars with low Cd affinity, the role of node Cd restriction on Cd accumulation in brown rice was studied. A pot experiment was conducted to investigate the concentration of Cd in different sections of 12 Chinese rice cultivars. The results indicated that the Cd accumulation in the brown rice was mainly dependent on the root or shoot Cd concentration. Among the cultivars with nearly equal shoot Cd concentrations, Cd accumulation in brown rice was mainly dependent on the transport of Cd in the shoot. However, the Cd transport in the shoot was significantly restricted by the nodes, especially by the first node. Furthermore, the area of the diffuse vascular bundle in the junctional region of the flag leaf and the first node was a key contributor to the variations in Cd restriction by the nodes.

  20. Geographic authentication of Asian rice (Oryza sativa L.) using multi-elemental and stable isotopic data combined with multivariate analysis.

    Science.gov (United States)

    Chung, Ill-Min; Kim, Jae-Kwang; Lee, Kyoung-Jin; Park, Sung-Kyu; Lee, Ji-Hee; Son, Na-Young; Jin, Yong-Ik; Kim, Seung-Hyun

    2018-02-01

    Rice (Oryza sativa L.) is the world's third largest food crop after wheat and corn. Geographic authentication of rice has recently emerged asan important issue for enhancing human health via food safety and quality assurance. Here, we aimed to discriminate rice of six Asian countries through geographic authentication using combinations of elemental/isotopic composition analysis and chemometric techniques. Principal components analysis could distinguish samples cultivated from most countries, except for those cultivated in the Philippines and Japan. Furthermore, orthogonal projection to latent structure-discriminant analysis provided clear discrimination between rice cultivated in Korea and other countries. The major common variables responsible for differentiation in these models were δ 34 S, Mn, and Mg. Our findings contribute to understanding the variations of elemental and isotopic compositions in rice depending on geographic origins, and offer valuable insight into the control of fraudulent labeling regarding the geographic origins of rice traded among Asian countries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Arsenic accumulation and phosphorus status in two rice (Oryza sativa L.) cultivars surveyed from fields in South China

    International Nuclear Information System (INIS)

    Lu Ying; Dong, Fei; Deacon, Claire; Chen Huojun; Raab, Andrea; Meharg, Andrew A.

    2010-01-01

    The consumption of paddy rice (Oryza sativa L.) is a major inorganic arsenic exposure pathway in S.E. Asia. A multi-location survey was undertaken in Guangdong Province, South China to assess arsenic accumulation and speciation in 2 rice cultivars, one an Indica and the other a hybrid Indica. The results showed that arsenic concentrations in rice tissue increased in the order grain < husk < straw < root. Rice grain arsenic content of 2 rice cultivars was significant different and correlated with phosphorus concentration and molar ratio of P/As in shoot, being higher for the Indica cultivar than for the hybrid Indica, which suggests altering shoot phosphorus status as a promising route for breeding rice cultivars with reduced grain arsenic. Speciation of grain arsenic, performed using HPLC-ICP-MS, identified inorganic arsenic as the dominant arsenic species present in the rice grain. - Altering rice shoot phosphorus status is a promising route for breeding rice cultivars with reduced grain arsenic.

  2. Hybridization study of wild rice Oryza glumaepatula with varieties of cultivated rice (O. sativa) and wild (O. grandiglumis)

    International Nuclear Information System (INIS)

    Villalobos Cascante, Eddier

    2015-01-01

    The process of interspecific hybridization of the wild species O. glumaepatula is studied with commercial varieties of the species O. sativa and O. grandiglumis, by morphological evaluation and hybrid flow cytometry. Hybrid plants were evaluated of cross between O. glumaepatula, located in the wetlands of Rio Medio Queso and two varieties of O. sativa, Puita Inta and CFX 18 resistant to a herbicide. The technique of Polymerase Chain Reaction Allele Specifies Oligonucleotide (PCR-ASO) was used to detect allelic mutations in the ALS gene conferring herbicide resistance, and it is confirmed the hybrid nature of the plants obtained at crossings. 68 hybrids were obtained: O. glumaepatula x P. Inta, 21 hybrids P. Inta x O. glumaepatula, 4 hybrids O. glumaepatula x CFX-18 and 15 hybrids CFX-18 x O. glumaepatula. 10 morphological descriptors of the genus Oryza were evaluated and determined that are indifferent to the direction and type of crossing, the hybrids resemble to the wild species O. glumaepatula for characters: height, panicle length and ligule length. All hybrids have showed similarity to commercial varieties in flag leaf length. Other characters evaluated in the hybrids have presented maternal effect, heterosis and intermediate values. The protocol of flow cytometry (FCM) is standardized species for Oryza genus analyzing nuclear DNA content of 106 samples of leaf tissue of wild species O. glumaepatula, O. grandiglumis; whose average has been of 0.73 picograms, and natural hybrids product of the cross of these species. The result has been intermediate compared with O. grandiglumis and O. glumaepatula that have made available to 1.0 picograms and 0.50 of DNA respectively. The molecular nature of the hybrids was confirmed in this way. (author) [es

  3. Efeito da irradiação gama nas características físico-químicas e sensoriais do arroz (Oryza sativa L. e no desenvolvimento de Sitophilus oryzae L. Effect of gamma irradiation on physico-chemical and sensorial characteristics of rice (Oryza sativa L. and on the development of Sitophilus oryzae L.

    Directory of Open Access Journals (Sweden)

    Cíntia Fernanda Pedroso Zanão

    2009-03-01

    Full Text Available A pesquisa teve como objetivo verificar a viabilidade da radiação gama como método de conservação do arroz polido (Oryza sativa L.. As amostras foram irradiadas com doses 0,5; 1,0; 3,0; e 5,0 kGy. Foram realizadas análises da quebra do grão no beneficiamento, da longevidade e reprodução do Sitophilus oryzae L., a composição centesimal, o conteúdo de amilose aparente e propriedades de pasta dos amidos, e análises para cor (instrumental e análise sensorial do arroz cru e cozido. Foi utilizado teste de Tukey (p The objective of this research was to verify the viability of the gamma radiation as polished rice (Oryza sativa L. conservation method. The samples were irradiated with doses of 0.5; 1.0; 3.0; and 5.0 kGy. Analysis of the grain breakage during the enriching process, longevity and reproduction of the Sitophilus oryzae L., centesimal composition, apparent amylose content, starch paste properties, color (instrumental, and the sensorial evaluation of raw and cooked rice were performed. It was verified that the irradiation did not change the percentage of grain breakage during the enrichment process, and it caused a negative effect on the development of insects. The irradiation did not change significantly the centesimal composition and the apparent amylase content. The Tukey test (p < 0.05 was conducted to verify the differences between the treatments. Gamma irradiation affected the pasting properties of the rice flour. Pasting parameters as temperature, peak, final viscosity, and setback values showed decreasing values with irradiation doses. Differences were detected in the sensorial aspect among the samples, and the sample irradiated with the dose of 1.0 kGy presented greater averages. Regarding the instrumental color parameter, it was observed the difference in the values b* indicating that the rice changed the white color for yellowish with the increase in the irradiation dose. The irradiation dose of 1.0 kGy proved the best

  4. Genetic analysis and fine mapping of LH1 and LH2, a set of complementary genes controlling late heading in rice (Oryza sativa L.).

    Science.gov (United States)

    Liu, Shuang; Wang, Feng; Gao, Li Jun; Li, Jin Hua; Li, Rong Bai; Gao, Han Liang; Deng, Guo Fu; Yang, Jin Shui; Luo, Xiao Jin

    2012-12-01

    Heading date in rice (Oryza sativa L.) is a critical agronomic trait with a complex inheritance. To investigate the genetic basis and mechanism of gene interaction in heading date, we conducted genetic analysis on segregation populations derived from crosses among the indica cultivars Bo B, Yuefeng B and Baoxuan 2. A set of dominant complementary genes controlling late heading, designated LH1 and LH2, were detected by molecular marker mapping. Genetic analysis revealed that Baoxuan 2 contains both dominant genes, while Bo B and Yuefeng B each possess either LH1 or LH2. Using larger populations with segregant ratios of 3 : 1, we fine-mapped LH1 to a 63-kb region near the centromere of chromosome 7 flanked by markers RM5436 and RM8034, and LH2 to a 177-kb region on the short arm of chromosome 8 between flanking markers Indel22468-3 and RM25. Some candidate genes were identified through sequencing of Bo B and Yuefeng B in these target regions. Our work provides a solid foundation for further study on gene interaction in heading date and has application in marker-assisted breeding of photosensitive hybrid rice in China.

  5. Genetic relationships between interspecific lines derived from Oryza glaberrima and Oryza sativa crosses using microsatellites and agro-morphological markers

    Energy Technology Data Exchange (ETDEWEB)

    Moukoumbi, Y.D.; Kolade, O.; Drame, K.N.; Sie, M.; Ndjiondjo, M.N.

    2015-07-01

    New Rice(s) for Africa (NERICA) are high yielding rice varieties mostly cultivated in Sub-Saharan Africa and developed by the Africa Rice Center. This study is aimed at investigating the proportion of introgression of parental genomic contribution of 60 lowland NERICA varieties and establishment of molecular profiling. Agro-morphological data from 17 characteristics was recorded and significant (p<0.05) to high significant (p<0.0001) differences were obtained with leaf length and width, plant height at maturity, days to heading, maturity, primary and secondary branching of panicles, and grain width and grain thickness. A total of 114 microsatellite polymorphic markers covering 2183.13 cM of the rice genome showed the proportions of alleles introgressed from the donor parent (Oryza glaberrima) into 52 lowland NERICA lines (TOG5681 and IR64) as follows: 11% for BC2, 6.07% for BC3, and 7.55% for BC4. The introgression proportions for the eight remaining lowland NERICA lines derived from other crosses ranged from 5.5 to 11.3%. The proportion recorded with the recurrent parent was 83.99%. The highest introgression proportions of the O. glaberrima allele for all 60 lowland NERICA lines were found on chromosomes 2, 6 and 12 (TOG5681/IR64) and on chromosome 3 with NERIC-L-29 (TOG5681/IR1529-680-3-2). Multivariate analyses performed using an association of agro-morphological and molecular data revealed two major groups according to the distribution of the lowland NERICAs including the lowland NERICAs released were found in cluster 1 of the dendrogram. Genetic and genomic studies, QTL identification and analysis using agro-morphologically significant traits revealed should be used to develop mega-varieties adapted in rice growth conditions in Sub-Saharan Africa. (Author)

  6. A genome-wide association study of a global rice panel reveals resistance in Oryza sativa to root-knot nematodes.

    Science.gov (United States)

    Dimkpa, Stanley O N; Lahari, Zobaida; Shrestha, Roshi; Douglas, Alex; Gheysen, Godelieve; Price, Adam H

    2016-02-01

    The root-knot nematode Meloidogyne graminicola is one of the most serious nematode pests worldwide and represents a major constraint on rice production. While variation in the susceptibility of Asian rice (Oryza sativa) exists, so far no strong and reliable resistance has been reported. Quantitative trait loci for partial resistance have been reported but no underlying genes have been tagged or cloned. Here, 332 accessions of the Rice Diversity Panel 1 were assessed for gall formation, revealing large variation across all subpopulations of rice and higher susceptibility in temperate japonica accessions. Accessions Khao Pahk Maw and LD 24 appeared to be resistant, which was confirmed in large pot experiments where no galls were observed. Detailed observations on these two accessions revealed no nematodes inside the roots 2 days after inoculation and very few females after 17 days (5 in Khao Pahk Maw and 100 in the susceptible controls). These two cultivars appear ideal donors for breeding root-knot nematode resistance. A genome-wide association study revealed 11 quantitative trait loci, two of which are close to epistatic loci detected in the Bala x Azucena population. The discussion highlights a small number of candidate genes worth exploring further, in particular many genes with lectin domains and genes on chromosome 11 with homology to the Hordeum Mla locus. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  7. Risk assessment of potentially toxic element pollution in soils and rice (Oryza sativa) in a typical area of the Yangtze River Delta

    International Nuclear Information System (INIS)

    Hang Xiaoshuai; Wang Huoyan; Zhou Jianmin; Ma Chengling; Du Changwen; Chen Xiaoqin

    2009-01-01

    Soil pollution with potentially toxic elements (PTEs) resulting from rapid industrial development has caused major concerns. Selected PTEs and their accumulation and distribution in soils and rice (Oryza sativa) collected from Changshu, east China, were analyzed to evaluate the potential health risk to the local population. The soils were primarily contaminated with Hg, followed by Cu, Cd, Pb, and Zn. The concentrations of Pb, Hg, and Cd of 46, 32, and 1 rice samples exceeded their national maximum allowable levels in foods, respectively. Spatial distributions of total Cr, Cu, Pb, Zn, and Cd in soils shared similar geographical trends. The risk assessment of PTEs through rice consumption suggests that the concentrations of Cu, Pb, and Cd in some rice samples exceed their reference oral dose for adults and children. In general, there was no target hazard quotient value of any individual element that was greater than 1, but hazard index values for adults and children were 1.726 and 1.523, respectively. - Industrial development has led to increased risk from potentially toxic elements in soils and rice.

  8. Screening of Oryza sativa L. for HptGene and Evaluation of Hpt Positive Samples Using Houba Retransposon-Based IRAP Markers

    Directory of Open Access Journals (Sweden)

    Gözde YÜZBAŞIOĞLU

    2017-02-01

    Full Text Available Increasing world population needs to enhance agricultural production because of food starvation. Genetically modified organism(GMOis a way to solve this problem. During gene transfers, DNA is inserted into a plant’s genome in a random way. Thisproducesspontaneous genetic changeswith movement of transposable elements, and even increasesvariations. Houbawas described as one of the active retrotransposonsin rice. The aim of this study was to screen rice samples collected from Turkey, and analyse Houba retrotransposon movements with IRAP technique intransgenic ones and their controls. For this purpose, 71 different rice seeds obtained from different regions of Turkey were used for GMO analysis.All samples were screened by real time PCR to test cauliflower mosaic virus (CaMV 35S promoter (P-35S regions, T-NOS (nopaline synthase terminator regions, figwort mosaic virus (FMV regions, bar, patand Cry1ab/ac,and hpt(hygromycin resistance genes. Hptgene was identified in 6samples as a result of real time PCR analysis. These 6transgenic samples with their controls were used for IRAP-PCRanalysisand 0-56% polymorphism ratios were observed in analysed samples. This study is one of the first detailed experimental data of transgenic Oryza sativaL. samples in terms of retrotransposon-based variation.

  9. Global Transcriptome Analysis of Combined Abiotic Stress Signaling Genes Unravels Key Players in Oryza sativa L.: An In silico Approach

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    Pandiyan Muthuramalingam

    2017-05-01

    Full Text Available Combined abiotic stress (CAbS affects the field grown plants simultaneously. The multigenic and quantitative nature of uncontrollable abiotic stresses complicates the process of understanding the stress response by plants. Considering this, we analyzed the CAbS response of C3 model plant, Oryza sativa by meta-analysis. The datasets of commonly expressed genes by drought, salinity, submergence, metal, natural expression, biotic, and abiotic stresses were data mined through publically accessible transcriptomic abiotic stress (AbS responsive datasets. Of which 1,175, 12,821, and 42,877 genes were commonly expressed in meta differential, individual differential, and unchanged expressions respectively. Highly regulated 100 differentially expressed AbS genes were derived through integrative meta-analysis of expression data (INMEX. Of this 30 genes were identified from AbS gene families through expression atlas that were computationally analyzed for their physicochemical properties. All AbS genes were physically mapped against O. sativa genome. Comparative mapping of these genes demonstrated the orthologous relationship with related C4 panicoid genome. In silico expression analysis of these genes showed differential expression patterns in different developmental tissues. Protein–protein interaction of these genes, represented the complexity of AbS. Computational expression profiling of candidate genes in response to multiple stresses suggested the putative involvement of OS05G0350900, OS02G0612700, OS05G0104200, OS03G0596200, OS12G0225900, OS07G0152000, OS08G0119500, OS06G0594700, and Os01g0393100 in CAbS. These potential candidate genes need to be studied further to decipher their functional roles in AbS dynamics.

  10. 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.

  11. Population Dynamics Among six Major Groups of the Oryza rufipogon Species Complex, Wild Relative of Cultivated Asian Rice.

    Science.gov (United States)

    Kim, HyunJung; Jung, Janelle; Singh, Namrata; Greenberg, Anthony; Doyle, Jeff J; Tyagi, Wricha; Chung, Jong-Wook; Kimball, Jennifer; Hamilton, Ruaraidh Sackville; McCouch, Susan R

    2016-12-01

    Understanding population structure of the wild progenitor of Asian cultivated rice (O. sativa), the Oryza rufipogon species complex (ORSC), is of interest to plant breeders and contributes to our understanding of rice domestication. A collection of 286 diverse ORSC accessions was evaluated for nuclear variation using genotyping-by-sequencing (113,739 SNPs) and for chloroplast variation using Sanger sequencing (25 polymorphic sites). Six wild subpopulations were identified, with 25 % of accessions classified as admixed. Three of the wild groups were genetically and geographically closely related to the O. sativa subpopulations, indica, aus and japonica, and carried O. sativa introgressions; the other three wild groups were genetically divergent, had unique chloroplast haplotypes, and were located at the geographical extremes of the species range. The genetic subpopulations were significantly correlated (r 2  = 0.562) with traditional species designations, O. rufipogon (perennial) and O. nivara (annual), differentiated based on morphology and life history. A wild diversity panel of 95 purified (inbred) accessions was developed for future genetic studies. Our results suggest that the cultivated aus subpopulation is most closely related to an annual wild relative, japonica to a perennial wild relative, and indica to an admixed population of diverse annual and perennial wild ancestors. Gene flow between ORSC and O. sativa is common in regions where rice is cultivated, threatening the identity and diversity of wild ORSC populations. The three geographically isolated ORSC populations harbor variation rarely seen in cultivated rice and provide a unique window into the genetic composition of ancient rice subpopulations.

  12. Duplication and diversification of the LEAFY HULL STERILE1 and Oryza sativa MADS5 SEPALLATA lineages in graminoid Poales

    Directory of Open Access Journals (Sweden)

    Christensen Ashley R

    2012-02-01

    Full Text Available Abstract Background Gene duplication and the subsequent divergence in function of the resulting paralogs via subfunctionalization and/or neofunctionalization is hypothesized to have played a major role in the evolution of plant form. The LEAFY HULL STERILE1 (LHS1 SEPALLATA (SEP genes have been linked with the origin and diversification of the grass spikelet, but it is uncertain 1 when the duplication event that produced the LHS1 clade and its paralogous lineage Oryza sativa MADS5 (OSM5 occurred, and 2 how changes in gene structure and/or expression might have contributed to subfunctionalization and/or neofunctionalization in the two lineages. Methods Phylogenetic relationships among 84 SEP genes were estimated using Bayesian methods. RNA expression patterns were inferred using in situ hybridization. The patterns of protein sequence and RNA expression evolution were reconstructed using maximum parsimony (MP and maximum likelihood (ML methods, respectively. Results Phylogenetic analyses mapped the LHS1/OSM5 duplication event to the base of the grass family. MP character reconstructions estimated a change from cytosine to thymine in the first codon position of the first amino acid after the Zea mays MADS3 (ZMM3 domain converted a glutamine to a stop codon in the OSM5 ancestor following the LHS1/OSM5 duplication event. RNA expression analyses of OSM5 co-orthologs in Avena sativa, Chasmanthium latifolium, Hordeum vulgare, Pennisetum glaucum, and Sorghum bicolor followed by ML reconstructions of these data and previously published analyses estimated a complex pattern of gain and loss of LHS1 and OSM5 expression in different floral organs and different flowers within the spikelet or inflorescence. Conclusions Previous authors have reported that rice OSM5 and LHS1 proteins have different interaction partners indicating that the truncation of OSM5 following the LHS1/OSM5 duplication event has resulted in both partitioned and potentially novel gene

  13. Exogenous application of rutin and gallic acid regulate antioxidants and alleviate reactive oxygen generation in Oryza sativa L.

    Science.gov (United States)

    Singh, Akanksha; Gupta, Rupali; Pandey, Rakesh

    2017-04-01

    The effect of rutin and gallic acid on growth, phytochemical and defense gene activation of rice ( Oryza sativa L.) was investigated. The seeds of rice were primed with different concentrations of rutin and gallic acid (10-60 µg mL -1 ) to explicate the effect on germination on water agar plates. Further, to study the effect of most effective concentrations of gallic acid (60 µg mL -1 ) and rutin (50 µg mL -1 ), greenhouse pot experiment was set up to determine the changes in growth, antioxidant and defense parameters. The results revealed more pronounced effect of gallic acid on total chlorophyll and carotenoids as well as on total flavonoid content and free radical scavenging activities. Gene expression analysis of OsWRKY71, PAL, CHS and LOX genes involved in strengthening the plant defense further validated the results obtained from the biochemical analysis. Microscopic analysis also confirmed reduction in total reactive oxygen species, free radicals like H 2 O 2 and O 2 - by exogenous application of gallic acid and rutin. The data obtained thus suggest that both gallic acid and rutin can affect the growth and physiology of rice plants and therefore can be used to develop effective plant growth promoters and as substitute of biofertilizers for maximizing their use in field conditions.

  14. Analysis of genetic and genotype X environment interaction effects for agronomic traits of rice (oryza sativa l.) in salt tolerance

    International Nuclear Information System (INIS)

    Zhou, H.K.; Hayat, Y.; Fang, L.J.; Guo, R.F.; He, J.M.; Xu, H.M.

    2010-01-01

    A diallel cross experiment of 4 rice (Oryza sativa L.) female and 6 male varieties was conducted to study the genetic effects and their interaction with salt-stress condition of 7 agronomic traits in normal and salt-stressed planting conditions. The panicle length (PL), effective number of panicles per plant (ENP), plumped number of grains per panicles (PNG), total number of grains per panicles (TNG), 1000-grain weight (W), seed setting ratio (SSR) and grain weight per plant (PGW), were investigated. A genetic model including additive effect, dominance effect and their interaction effects with environment (ADE) was employed for analysis of data. It was observed that significant (p<0.05) additive effects, dominance effects, additive X environment interaction effects and dominance X environment interaction effects exist for most of the agronomic traits of rice. In addition, significant (p<0.05) narrow sense heritabilities of ENP, PNG, TNG, W and PGW were found, indicating that the genetic performance of these traits are greatly affected by salt stress condition. A significant (p<0.05) negative correlations in the additive effects and additive X environment interaction effects detected between ENP and PNG suggesting that selection on increasing of ENP can reduce PNG. In addition, there exist a highly significant (p<0.01) positive dominance correlation among the dominance effects of the ENP, PNG and TNG, which shows that it is possible to breed salt-tolerant rice variety by coordinating large panicle and multi-panicle in utilization of heterosis. (author)

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  16. Role of salicylic acid in alleviating oxidative damage in rice roots (Oryza sativa) subjected to cadmium stress

    International Nuclear Information System (INIS)

    Guo, B.; Liang, Y.C.; Zhu, Y.G.; Zhao, F.J.

    2007-01-01

    Time-dependent changes in enzymatic and non-enzymatic antioxidants, and lipid peroxidation were investigated in roots of rice (Oryza sativa) grown hydroponically with Cd, with or without pretreatment of salicylic acid (SA). Exposure to 50 μM Cd significantly decreased root growth, and activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), but increased the concentrations of H 2 O 2 , malondialdehyde (MDA), ascorbic acid (AsA), glutathione (GSH) and non-protein thiols (NPT). However, pretreatment with 10 μM SA enhanced the activities of antioxidant enzymes and the concentrations of non-enzymatic antioxidants, but lowered the concentrations of H 2 O 2 and MDA in the Cd-stressed rice compared with the Cd treatment alone. Pretreatment with SA alleviated the Cd-induced inhibition of root growth. The results showed that pretreatment with SA enhanced the antioxidant defense activities in Cd-stressed rice, thus alleviating Cd-induced oxidative damage and enhancing Cd tolerance. The possible mechanism of SA-induced H 2 O 2 signaling in mediating Cd tolerance was discussed. - Pretreatment with SA enhanced the antioxidant defense activities in Cd-stressed rice, thus alleviating Cd-induced oxidative damage and enhancing Cd tolerance

  17. Glomus mosseae enhances root growth and Cu and Pb acquisition of upland rice (Oryza sativa L.) in contaminated soils.

    Science.gov (United States)

    Lin, Aijun; Zhang, Xuhong; Yang, Xiaojin

    2014-12-01

    A pot culture experiment was carried out to investigate the roles of Glomus mosseae in Cu and Pb acquisition by upland rice (Oryza sativa L.) and the interactions between Cu and Pb. The soil was treated with three Cu levels (0, 100 and 200 mg kg(-1)) and three Pb levels (0, 300, and 600 mg kg(-1)). All treatments were designed with (+M) or without (-M) G. mosseae inoculation in a randomized block design. The addition of Cu and Pb significantly decreased root mycorrhizal colonization. Compared with -M, +M significantly increased root biomass in almost all treatments, and also significantly increased shoot biomass in the Pb(0)Cu(200), Pb(300)Cu(0), and all Pb(600) treatments. AM fungi enhanced plant Cu acquisition, but decreased plant Cu concentrations with all Cu plus Pb treatments, except for shoot in the Cu(200)Pb(600) treatment. Irrespective of Cu and Pb levels, +M plants had higher Pb uptakes than -M plants, but had lower root Pb and higher shoot Pb concentrations than those of -M plants. Another interpretation for the higher shoot Pb concentration in +M plants relied on Cu-Pb interactions. The study provided further evidences for the protective effects of AM fungi on upland rice against Cu and Pb contamination, and uncovered the phenomenon that Cu addition could promote Pb uptake and Pb partitioning to shoot. The possible mechanisms by which AM fungi can alleviate the toxicity induced by Cu and Pb are also discussed.

  18. Black Rice (Oryza sativa L., Poaceae) Extract Reduces Hippocampal Neuronal Cell Death Induced by Transient Global Cerebral Ischemia in Mice.

    Science.gov (United States)

    Hwang, Sun-Nyoung; Kim, Jae-Cheon; Bhuiyan, Mohammad Iqbal Hossain; Kim, Joo Youn; Yang, Ji Seon; Yoon, Shin Hee; Yoon, Kee Dong; Kim, Seong Yun

    2018-04-01

    Rice is the most commonly consumed grain in the world. Black rice has been suggested to contain various bioactive compounds including anthocyanin antioxidants. There is currently little information about the nutritional benefits of black rice on brain pathology. Here, we investigated the effects of black rice ( Oryza sativa L ., Poaceae) extract (BRE) on the hippocampal neuronal damage induced by ischemic insult. BRE (300 mg/kg) was orally administered to adult male C57BL/6 mice once a day for 21 days. Bilateral common carotid artery occlusion (BCCAO) was performed for 23 min on the 8th day of BRE or vehicle administration. Histological analyses conducted on the 22nd day of BRE or vehicle administration revealed that administering BRE profoundly attenuated neuronal cell death, inhibited reactive astrogliosis, and prevented loss of glutathione peroxidase expression in the hippocampus when compared to vehicle treatment. In addition, BRE considerably ameliorated BCCAO-induced memory impairment on the Morris water maze test from the 15th day to the 22nd day of BRE or vehicle administration. These results indicate that chronic administration of BRE is potentially beneficial in cerebral ischemia.

  19. Combined Mass Spectrometry-Based Metabolite Profiling of Different Pigmented Rice (Oryza sativa L. Seeds and Correlation with Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Ga Ryun Kim

    2014-09-01

    Full Text Available Nine varieties of pigmented rice (Oryza sativa L. seeds that were black, red, or white were used to perform metabolite profiling by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS and gas chromatography (GC TOF-MS, to measure antioxidant activities. Clear grouping patterns determined by the color of the rice seeds were identified in principle component analysis (PCA derived from UPLC-Q-TOF-MS. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimer, proanthocyanidin trimer, apigenin-6-C-glugosyl-8-C-arabiboside, tricin-O-rhamnoside-O-hexoside, and lipids were identified as significantly different secondary metabolites. In PCA score plots derived from GC-TOF-MS, Jakwangdo (JKD and Ilpoom (IP species were discriminated from the other rice seeds by PC1 and PC2. Valine, phenylalanine, adenosine, pyruvate, nicotinic acid, succinic acid, maleic acid, malonic acid, gluconic acid, xylose, fructose, glucose, maltose, and myo-inositol were significantly different primary metabolites in JKD species, while GABA, asparagine, xylitol, and sucrose were significantly distributed in IP species. Analysis of antioxidant activities revealed that black and red rice seeds had higher activity than white rice seeds. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimers, proanthocyanidin trimers, and catechin were highly correlated with antioxidant activities, and were more plentiful in black and red rice seeds. These results are expected to provide valuable information that could help improve and develop rice-breeding techniques.

  20. Black rice (Oryza sativa L.) extracts induce osteoblast differentiation and protect against bone loss in ovariectomized rats.

    Science.gov (United States)

    Jang, Woo-Seok; Seo, Cho-Rong; Jang, Hwan Hee; Song, No-Joon; Kim, Jong-Keun; Ahn, Jee-Yin; Han, Jaejoon; Seo, Woo Duck; Lee, Young Min; Park, Kye Won

    2015-01-01

    Osteoporosis, an age associated skeletal disease, exhibits increased adipogenesis at the expense of osteogenesis from common osteoporotic bone marrow cells. In this study, black rice (Oryza sativa L.) extracts (BRE) were identified as osteogenic inducers. BRE stimulated the alkaline phosphatase (ALP) activity in both C3H10T1/2 and primary bone marrow cells. Similarly, BRE increased mRNA expression of ALP and osterix. Oral administration of BRE in OVX rats prevented decreases in bone density and strength. By contrast, BRE inhibited adipocyte differentiation of mesenchymal C3H10T1/2 cells and prevented increases in body weight and fat mass in high fat diet fed obese mice, further suggesting the dual effects of BRE on anti-adipogenesis and pro-osteogenesis. UPLC analysis identified cyanidin-3-O-glucoside and peonidin-3-O-glucoside as main anti-adipogenic effectors but not for pro-osteogenic induction. In mechanism studies, BRE selectively stimulated Wnt-driven luciferase activities. BRE treatment also induced Wnt-specific target genes such as Axin2, WISP2, and Cyclin D1. Taken together, these data suggest that BRE is a potentially useful ingredient to protect against age related osteoporosis and diet induced obesity.

  1. Distribution of Silicified Microstructures, Regulation of Cinnamyl Alcohol Dehydrogenase and Lodging Resistance in Silicon and Paclobutrazol Mediated Oryza sativa

    Directory of Open Access Journals (Sweden)

    Deivaseeno Dorairaj

    2017-07-01

    Full Text Available Lodging is a phenomenon that affects most of the cereal crops including rice, Oryza sativa. This is due to the fragile nature of herbaceous plants whose stems are non-woody, thus affecting its ability to grow upright. Silicon (Si, a beneficial nutrient is often used to toughen and protect plants from biotic and abiotic stresses. Deposition of Si in plant tissues enhances the rigidity and stiffness of the plant as a whole. Silicified cells provide the much needed strength to the culm to resist breaking. Lignin plays important roles in cell wall structural integrity, stem strength, transport, mechanical support, and plant pathogen defense. The aim of this study is to resolve effects of Si on formation of microstructure and regulation of cinnamyl alcohol dehydrogenase (CAD, a key gene responsible for lignin biosynthesis. Besides evaluating silicon, paclobutrazol (PBZ a plant growth retartdant that reduces internode elongation is also incorporated in this study. Hardness, brittleness and stiffness were improved in presence of silicon thus reducing lodging. Scanning electron micrographs with the aid of energy dispersive x-ray (EDX was used to map silicon distribution. Presence of trichomes, silica cells, and silica bodies were detected in silicon treated plants. Transcripts of CAD gene was also upregulated in these plants. Besides, phloroglucinol staining showed presence of lignified vascular bundles and sclerenchyma band. In conclusion, silicon treated rice plants showed an increase in lignin content, silicon content, and formation of silicified microstructures.

  2. Silicon alleviates simulated acid rain stress of Oryza sativa L. seedlings by adjusting physiology activity and mineral nutrients.

    Science.gov (United States)

    Ju, Shuming; Wang, Liping; Yin, Ningning; Li, Dan; Wang, Yukun; Zhang, Cuiying

    2017-11-01

    Silicon (Si) has been a modulator in plants under abiotic stresses, such as acid rain. To understand how silicon made an effect on rice (Oryza sativa L.) exposed to simulated acid rain (SAR) stress, the growth, physiologic activity, and mineral nutrient content in leaves of rice were investigated. The results showed that combined treatments with Si (1.0, 2.0, or 4.0 mM) and SAR (pH 4.0, 3.0, or 2.0) obviously improved the rice growth compared with the single treatment with SAR. Incorporation of Si into SAR treatment decreased malondialdehyde (MDA) content; increased soluble protein and proline contents; promoted CAT, POD, SOD, and APX activity; and maintained the K, Ca, Mg, Fe, Zn, Cu content balance in leaves of rice seedlings under SAR stress. The moderate concentration of Si (2.0 mM) was better than the low and high concentration of Si (1.0 and 4.0 mM). Therefore, application of Si could be a better strategy for maintaining the crop productivity in acid rain regions.

  3. Can Cd translocation in Oryza sativa L. be attenuated by arbuscular mycorrhizal fungi in the presence of EDTA?

    Science.gov (United States)

    Huang, Xiaochen; An, Guangnan; Zhu, Shishu; Wang, Li; Ma, Fang

    2018-04-01

    Arbuscular mycorrhizal (AM) fungi play an important role in plant tolerance of heavy metal contamination. In this study, a pot experiment was conducted to illustrate the effects of the two AM fungi species Funneliformis mosseae (Fm) and Rhizophagus irregularis (Ri) on plant growth of Oryza sativa L. either with or without ethylenediamine tetraacetate (EDTA) addition and during exposure to five Cd concentrations (in the range of 0-5 mg kg -1 ). The results showed that Fm inoculation achieved greater mycorrhizal colonization and mycorrhizal dependency indexes than Ri inoculation. In addition, the effects of AM fungi on Cd biosorption and translocation in rice were also investigated in the presence of EDTA. Despite cooperative adsorption, the Freundlich isotherm could describe the biosorption effects of Cd on rice roots regardless of AM fungi inoculation or EDTA addition. Cd concentrations in mycorrhizal roots increased but decreased in mycorrhizal shoots in contrast to the control treatment. Although EDTA addition negatively inhibited the uptake of Cd to mycorrhizal shoots, lower translocation factor (TF) and bioconcentration factor (BCF) were still observed in treatments with EDTA compared to control treatment. Our findings suggest that Ri and Fm inoculation enhanced Cd immobilization in the roots, thus preventing Cd entry into the food chain during exposure to low and high Cd stress, respectively.

  4. Influence of chelating ligands on arsenic uptake by hydroponically grown rice seedlings (Oryza sativa L.): a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Mohammad A.; Hasegawa, Hiroshi; Ueda, Kazumasa; Maki, Teruya [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa (Japan); Rahman, M.M. [Department of Botany, Faculty of Biological Sciences, Jahangirnagar University, Savar, Dhaka (Bangladesh)

    2008-06-15

    Ferric (oxyhydro-)oxides (FeO{sub x}) precipitate in the rhizosphere at neutral or alkaline pH and are adsorbed on the plant root surfaces. Consequently, the higher binding affinity of arsenate to FeO{sub x} and the low iron phytoavailability of the precipitated FeO{sub x} make the phytoremediation of arsenic difficult. In the present study, the influence of chelating ligands on arsenic and iron uptake by hydroponically grown rice seedlings (Oryza sativa L.) was investigated. When chelating ligands were not treated to the growth medium, about 63 and 71% of the total arsenic and iron were distributed in the root extract (outer root surfaces) of rice, respectively. On the other hand, ethylenediaminetetraacetic acid (EDTA), ethylenediaminedisuccinic acid (EDDS) and hydroxyiminodisuccinic acid (HIDS) desorbed a significant amount of arsenic from FeO{sub x} of the outer root surfaces. Therefore, the uptake of arsenic and iron into the roots and their subsequent translocation to the shoots of the rice seedlings increased significantly. The order of increasing arsenic uptake by chelating ligands was HIDS > EDTA > EDDS. Methylglycinediacetic acid (MGDA) and iminodisuccinic acid (IDS) might not be effective in arsenic solubilization from FeO{sub x}. The results suggest that EDDS and HIDS would be a good and environmentally safe choice to accelerate arsenic phytoavailability in the phytoremediation process because of their biodegradability and would be a competent alternative to the widely used non-biodegradable and environmentally persistent EDTA. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  6. OsPIN5b modulates rice (Oryza sativa) plant architecture and yield by changing auxin homeostasis, transport and distribution.

    Science.gov (United States)

    Lu, Guangwen; Coneva, Viktoriya; Casaretto, José A; Ying, Shan; Mahmood, Kashif; Liu, Fang; Nambara, Eiji; Bi, Yong-Mei; Rothstein, Steven J

    2015-09-01

    Plant architecture attributes such as tillering, plant height and panicle size are important agronomic traits that determine rice (Oryza sativa) productivity. Here, we report that altered auxin content, transport and distribution affect these traits, and hence rice yield. Overexpression of the auxin efflux carrier-like gene OsPIN5b causes pleiotropic effects, mainly reducing plant height, leaf and tiller number, shoot and root biomass, seed-setting rate, panicle length and yield parameters. Conversely, reduced expression of OsPIN5b results in higher tiller number, more vigorous root system, longer panicles and increased yield. We show that OsPIN5b is an endoplasmic reticulum (ER) -localized protein that participates in auxin homeostasis, transport and distribution in vivo. This work describes an example of an auxin-related gene where modulating its expression can simultaneously improve plant architecture and yield potential in rice, and reveals an important effect of hormonal signaling on these traits. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  7. Molecular cloning and characterization of RGA1 encoding a G protein alpha subunit from rice (Oryza sativa L. IR-36).

    Science.gov (United States)

    Seo, H S; Kim, H Y; Jeong, J Y; Lee, S Y; Cho, M J; Bahk, J D

    1995-03-01

    A cDNA clone, RGA1, was isolated by using a GPA1 cDNA clone of Arabidopsis thaliana G protein alpha subunit as a probe from a rice (Oryza sativa L. IR-36) seedling cDNA library from roots and leaves. Sequence analysis of genomic clone reveals that the RGA1 gene has 14 exons and 13 introns, and encodes a polypeptide of 380 amino acid residues with a calculated molecular weight of 44.5 kDa. The encoded protein exhibits a considerable degree of amino acid sequence similarity to all the other known G protein alpha subunits. A putative TATA sequence (ATATGA), a potential CAAT box sequence (AGCAATAC), and a cis-acting element, CCACGTGG (ABRE), known to be involved in ABA induction are found in the promoter region. The RGA1 protein contains all the consensus regions of G protein alpha subunits except the cysteine residue near the C-terminus for ADP-ribosylation by pertussis toxin. The RGA1 polypeptide expressed in Escherichia coli was, however, ADP-ribosylated by 10 microM [adenylate-32P] NAD and activated cholera toxin. Southern analysis indicates that there are no other genes similar to the RGA1 gene in the rice genome. Northern analysis reveals that the RGA1 mRNA is 1.85 kb long and expressed in vegetative tissues, including leaves and roots, and that its expression is regulated by light.

  8. Identification of a Rice stripe necrosis virus resistance locus and yield component QTLs using Oryza sativa × O. glaberrima introgression lines

    Directory of Open Access Journals (Sweden)

    Prado Gustavo

    2010-01-01

    Full Text Available Abstract Background Developing new population types based on interspecific introgressions has been suggested by several authors to facilitate the discovery of novel allelic sources for traits of agronomic importance. Chromosome segment substitution lines from interspecific crosses represent a powerful and useful genetic resource for QTL detection and breeding programs. Results We built a set of 64 chromosome segment substitution lines carrying contiguous chromosomal segments of African rice Oryza glaberrima MG12 (acc. IRGC103544 in the genetic background of Oryza sativa ssp. tropical japonica (cv. Caiapó. Well-distributed simple-sequence repeats markers were used to characterize the introgression events. Average size of the substituted chromosomal segments in the substitution lines was about 10 cM and covered the whole donor genome, except for small regions on chromosome 2 and 4. Proportions of recurrent and donor genome in the substitution lines were 87.59% and 7.64%, respectively. The remaining 4.78% corresponded to heterozygotes and missing data. Strong segregation distortion was found on chromosomes 3 and 6, indicating the presence of interspecific sterility genes. To illustrate the advantages and the power of quantitative trait loci (QTL detection using substitution lines, a QTL detection was performed for scored traits. Transgressive segregation was observed for several traits measured in the population. Fourteen QTLs for plant height, tiller number per plant, panicle length, sterility percentage, 1000-grain weight and grain yield were located on chromosomes 1, 3, 4, 6 and 9. Furthermore, a highly significant QTL controlling resistance to the Rice stripe necrosis virus was located between SSR markers RM202-RM26406 (44.5-44.8 cM on chromosome 11. Conclusions Development and phenotyping of CSSL libraries with entire genome coverage represents a useful strategy for QTL discovery. Mapping of the RSNV locus represents the first identification

  9. Efecto de la cobertura de rastrojos en la germinación del arroz (Oryza sativa L. y principales malezas asociadas

    Directory of Open Access Journals (Sweden)

    Yemel M. Ortega

    2005-01-01

    Full Text Available Efecto de la cobertura de rastrojos en la germinacióndel arroz (Oryza sativaL. y principales malezas asociadas. Para determinar el grado de interferencia causado por distintas cantidades de rastrojos de arroz (Oryza sativaL. sobrela emergencia de arroz y malezas asociadas al cultivo, en el2003 se realizaron tres experimentos simultáneos en la hacienda el Pelón de la Bajura, Guanacaste, Costa Rica. Se aplicaron nueve tratamientos (0 a 9 t/ha de coberturas con rastrojosde la variedad de arroz CR 1113 para medir los efectos en laemergencia del arroz y malezas. Las malezas asociadas incluyen las más frecuentes en agroecosistemas arroceros inundados: Oryza sativa, Echinochloa colona, Cyperusspp., Fim-bristylisspp., Ludwigiaspp. y Heteranthera limosa. En losprimeros dos experimentos se determinaron relaciones inversas entre el grado de cobertura y la densidad de plántulas demalezas emergidas (R2>0,89, y entre el grado de cobertura yel porcentaje de germinación del arroz (R2=0,86, respectivamente. Usando coberturas con rastrojos de frijol (Phaseolusvulgaris en el tercer experimento, no se observó efecto supresor en la germinación del arroz, probablemente debido a supronta descomposición. Aunque la germinación del arroz nose afectó aún a las intensidades más altas de rastrojos evaluadas, conviene realizar pruebas similares a largo plazo para determinar posibles efectos debidos a la descomposición de residuos, alelopatía y acarreo de herbicidas después de variosciclos consecutivos del cultivo de arroz.

  10. Why develop O. sativa x O. rufipogon chromosome segment substitution line libraries?

    Science.gov (United States)

    Transgressive variation has been observed in rice (Oryza sativa) as an increase in grain yield in advanced backcross mapping populations derived from crosses between several adapted O. sativa varieties and a single accession (IRGC105491) of the ancestral parent, O. rufipogon. The phenomena of hybrid...

  11. Are habitat fragmentation, local adaptation and isolation-by-distance driving population divergence in wild rice Oryza rufipogon?

    Science.gov (United States)

    Zhao, Yao; Vrieling, Klaas; Liao, Hui; Xiao, Manqiu; Zhu, Yongqing; Rong, Jun; Zhang, Wenju; Wang, Yuguo; Yang, Ji; Chen, Jiakuan; Song, Zhiping

    2013-11-01

    Habitat fragmentation weakens the connection between populations and is accompanied with isolation by distance (IBD) and local adaptation (isolation by adaptation, IBA), both leading to genetic divergence between populations. To understand the evolutionary potential of a population and to formulate proper conservation strategies, information on the roles of IBD and IBA in driving population divergence is critical. The putative ancestor of Asian cultivated rice (Oryza sativa) is endangered in China due to habitat loss and fragmentation. We investigated the genetic variation in 11 Chinese Oryza rufipogon populations using 79 microsatellite loci to infer the effects of habitat fragmentation, IBD and IBA on genetic structure. Historical and current gene flows were found to be rare (mh  = 0.0002-0.0013, mc  = 0.007-0.029), indicating IBD and resulting in a high level of population divergence (FST  = 0.343). High within-population genetic variation (HE  = 0.377-0.515), relatively large effective population sizes (Ne  = 96-158), absence of bottlenecks and limited gene flow were found, demonstrating little impact of recent habitat fragmentation on these populations. Eleven gene-linked microsatellite loci were identified as outliers, indicating local adaptation. Hierarchical AMOVA and partial Mantel tests indicated that population divergence of Chinese O. rufipogon was significantly correlated with environmental factors, especially habitat temperature. Common garden trials detected a significant adaptive population divergence associated with latitude. Collectively, these findings imply that IBD due to historical rather than recent fragmentation, followed by local adaptation, has driven population divergence in O. rufipogon. © 2013 John Wiley & Sons Ltd.

  12. Pengaruh Pemberian Kompos Jerami Dan Pupuk Sp-36 Pada Tanah Sulfat Masam Potensial Terhadap Perubahan Sifat Kimia Serta Pertumbuhan Dan Produksi Padi (Oryza Sativa L.)

    OpenAIRE

    Bhakari, Herlina Eka

    2013-01-01

    The objective of this research is to study the effect of rice straw compost and the application of phosphorus fertilizer of SP-36 on chemical characteristic of acid sulphate soils, rice growth and production (Oryza sativa L). This study used a randomized block design factorial, with 2 factors : factor 1 : rice straw compost treatment (J) wich consist of : J0 = 0 ton ha-1 (0 g straw/pot) ; J1 = 10 ton ha-1 (40 g straw/pot); J2 = 20 ton ha-1 (80 g straw /pot); J3 = 30 ton ha-1 ...

  13. Application of glycine reduces arsenic accumulation and toxicity in Oryza sativa L. by reducing the expression of silicon transporter genes.

    Science.gov (United States)

    Kumar Dubey, Arvind; Kumar, Navin; Ranjan, Ruma; Gautam, Ambedkar; Pande, Veena; Sanyal, Indraneel; Mallick, Shekhar

    2018-02-01

    The present study was intended to investigate the role of amino acid glycine in detoxification of As in Oryza sativa L. The growth parameters such as, shoot length and fresh weight were decreased during As(III) and As(V) toxicity. However, the application of glycine recovered the growth parameters against As stress. The application of glycine reduced the As accumulation in all the treatments, and it was more effective against As(III) treatment and reduced the accumulation by 68% in root and 71% in shoot. Similarly, the translocation of As from root to shoot, was higher against As(III) and As(V) treatments, whereas, reduced upon glycine application. The translocation of Fe and Na was also affected by As, which was lower under As(III) and As(V) treatments. However, the application of glycine significantly enhanced the translocation of Fe and Na in the shoot. Besides, the expression of lower silicon transporters i.e. Lsi-1 and Lsi-2 was observed to be significantly suppressed in the root with the application of glycine against As treatment. Similarly, the expression of three GRX and two GST gene isoforms were found to be significantly increased with glycine application. Simultaneously, the activities of antioxidant enzymes i.e. l-arginine dependent NOS, SOD, NTR and GRX were found to be significantly enhanced in the presence of glycine. Increased activities of antioxidant enzymes coincided with the decreased level of TBARS and H 2 O 2 in rice seedlings. Overall, the results suggested that the application of glycine reduces As accumulation through suppressing the gene expression of lower silicon transporters and ameliorates As toxicity by enhancing antioxidants defense mechanism in rice seedlings. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Chloroplast DNA polymorphism and evolutional relationships between Asian cultivated rice (Oryza sativa) and its wild relatives (O. rufipogon).

    Science.gov (United States)

    Li, W J; Zhang, B; Huang, G W; Kang, G P; Liang, M Z; Chen, L B

    2012-12-17

    We analyzed chloroplast DNA (cpDNA) polymorphism and phylogenic relationships between 6 typical indica rice, 4 japonica rice, 8 javanica rice, and 12 Asian common wild rice (Oryza rufipogon) strains collected from different latitudes in China by comparing polymorphism at 9 highly variable regions. One hundred and forty-four polymorphic bases were detected. The O. rufipogon samples had 117 polymorphic bases, showing rich genetic diversity. One hundred and thirty-one bases at 13 sites were identified with indica/japonica characteristics; they showed differences between the indica and japonica subspecies at these sites. The javanica strains and japonica shared similar bases at these 131 polymorphic sites, suggesting that javanica is closely related to japonica. On the basis of length analyses of the open reading frame (ORF)100 and (ORF)29-tRNA-Cys(GCA) (TrnC(GCA)) fragments, the O. rufipogon strains were classified into indica/japonica subgroups, which was consistent with the results of the phylogenic tree assay based on concatenated datasets. These results indicated that differences in indica and japonica also exist in the cpDNA genome of the O. rufipogon strains. However, these differences demonstrated a certain degree of primitiveness and incompleteness, as an O. rufipogon line may show different indica/ japonica attributes at different sites. Consequently, O. rufipogon cannot be simply classified into the indica/japonica types as O. sativa. Our data support the hypothesis that Asian cultivated rice, O. indica and O. japonica, separately evolved from Asian common wild rice (O. rufipogon) strains, which have different indica-japonica differentiation trends.

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  16. iTRAQ-based proteomic analysis reveals the mechanisms of silicon-mediated cadmium tolerance in rice (Oryza sativa) cells.

    Science.gov (United States)

    Ma, Jie; Sheng, Huachun; Li, Xiuli; Wang, Lijun

    2016-07-01

    Silicon (Si) can alleviate cadmium (Cd) stress in rice (Oryza sativa) plants, however, the understanding of the molecular mechanisms at the single-cell level remains limited. To address these questions, we investigated suspension cells of rice cultured in the dark environment in the absence and presence of Si with either short- (12 h) or long-term (5 d) Cd treatments using a combination of isobaric tags for relative and absolute quantitation (iTRAQ), fluorescent staining, and inductively coupled plasma mass spectroscopy (ICP-MS). We identified 100 proteins differentially regulated by Si under the short- or long-term Cd stress. 70% of these proteins were down-regulated, suggesting that Si may improve protein use efficiency by maintaining cells in the normal physiological status. Furthermore, we showed two different mechanisms for Si-mediated Cd tolerance. Under the short-term Cd stress, the Si-modified cell walls inhibited the uptake of Cd ions into cells and consequently reduced the expressions of glycosidase, cell surface non-specific lipid-transfer proteins (nsLTPs), and several stress-related proteins. Under the long-term Cd stress, the amount of Cd in the cytoplasm in Si-accumulating (+Si) cells was decreased by compartmentation of Cd into vacuoles, thus leading to a lower expression of glutathione S-transferases (GST). These results provide protein-level insights into the Si-mediated Cd detoxification in rice single cells. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Transgenerational inheritance of modified DNA methylation patterns and enhanced tolerance induced by heavy metal stress in rice (Oryza sativa L.).

    Science.gov (United States)

    Ou, Xiufang; Zhang, Yunhong; Xu, Chunming; Lin, Xiuyun; Zang, Qi; Zhuang, Tingting; Jiang, Lili; von Wettstein, Diter; Liu, Bao

    2012-01-01

    DNA methylation is sensitive and responsive to stressful environmental conditions. Nonetheless, the extent to which condition-induced somatic methylation modifications can impose transgenerational effects remains to be fully understood. Even less is known about the biological relevance of the induced epigenetic changes for potentially altered well-being of the organismal progenies regarding adaptation to the specific condition their progenitors experienced. We analyzed DNA methylation pattern by gel-blotting at genomic loci representing transposable elements and protein-coding genes in leaf-tissue of heavy metal-treated rice (Oryza sativa) plants (S0), and its three successive organismal generations. We assessed expression of putative genes involved in establishing and/or maintaining DNA methylation patterns by reverse transcription (RT)-PCR. We measured growth of the stressed plants and their unstressed progenies vs. the control plants. We found (1) relative to control, DNA methylation patterns were modified in leaf-tissue of the immediately treated plants, and the modifications were exclusively confined to CHG hypomethylation; (2) the CHG-demethylated states were heritable via both maternal and paternal germline, albeit often accompanying further hypomethylation; (3) altered expression of genes encoding for DNA methyltransferases, DNA glycosylase and SWI/SNF chromatin remodeling factor (DDM1) were induced by the stress; (4) progenies of the stressed plants exhibited enhanced tolerance to the same stress their progenitor experienced, and this transgenerational inheritance of the effect of condition accompanying heritability of modified methylation patterns. Our findings suggest that stressful environmental condition can produce transgenerational epigenetic modifications. Progenies of stressed plants may develop enhanced adaptability to the condition, and this acquired trait is inheritable and accord with transmission of the epigenetic modifications. We suggest

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  19. Growth and Cd uptake by rice (Oryza sativa) in acidic and Cd-contaminated paddy soils amended with steel slag.

    Science.gov (United States)

    He, Huaidong; Tam, Nora F Y; Yao, Aijun; Qiu, Rongliang; Li, Wai Chin; Ye, Zhihong

    2017-12-01

    Contamination of rice (Oryza sativa) by Cd is of great concern. Steel slag could be used to amend Cd-contaminated soils and make them safe for cereal production. This work was conducted to study the effects of steel slag on Cd uptake and growth of rice plants in acidic and Cd-contaminated paddy soils and to determine the possible mechanisms behind these effects. Pot (rhizobag) experiments were conducted using rice plants grown on two acidic and Cd-contaminated paddy soils with or without steel slag amendment. Steel slag amendment significantly increased grain yield by 36-45% and root catalase activity, and decreased Cd concentrations in brown rice by 66-77% compared with the control, in both soils. Steel slag amendment also markedly decreased extractable soil Cd, Cd concentrations in pore-water and Cd translocation from roots to above-ground parts. It also significantly increased soil pH, extractable Si and Ca in soils and Ca concentrations in roots. Significant positive correlations were found between extractable soil Cd and Cd concentrations in rice tissues, but it was negatively correlated with soil pH and extractable Si. Calcium in root tissues significantly and negatively correlated with Cd translocation factors from roots to straw. Overall, steel slag amendment not only significantly promoted rice growth but decreased Cd accumulation in brown rice. These benefits appear to be related to improvements in soil conditions (e.g. increasing pH, extractable Si and Ca), a reduction in extractable soil Cd, and suppression of Cd translocation from roots to above-ground parts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Seed Germination Behaviors Of Some Aerobic Rice Cultivars Oryza Sativa L After Priming With Polyethylene Glycol-8000 Peg-8000

    Directory of Open Access Journals (Sweden)

    Elkheir H.A

    2015-08-01

    Full Text Available Seed Priming Is Famous Technique To Accelerate Seed Germination Behaviors. This Experiment Was Conducted To Study The Effect Of Polyethylene Glycol-8000 Peg-8000 As Priming Agent On Seed Germination Behavior Of Some Aerobic Rice Cultivars Oryza Sativa L. Experiment Was Carried Out By Using Two-Factor Three Aerobic Rice Cultivars And Peg With Four Replications Which Arranged In Factorial System Design And Conducted With Completely Randomized Design. The Factor Was Varieties Which Were Inpago 8 V1 Ir64 V2 And Situbagendit V3 Combine With 4 Levels Of Peg Concentrations 0100 And 200 Gl-1 And Control With No Treatment. Experiment Was Repeated 4 Times So Total Number Of Experimental Units Were 48. Germination Parameters Measured Were Germination Percentage Germination Index Days Of 50 Germination Seedling Fresh Weight Mg Seedling Shoot Fresh Weight And Root Fresh Weight Mg Seedling Dry Weigh Mg Seedling Shoot Dry Weight And Root Dry Weight Mg ShootRoot Ratio Seedling Length Cm Seedling Root Length Cm And Shoot Length Cm And Seed Vigor Index. The Results Indicated That Seed Priming Significantly Affected Germination Behaviors Compared With Control Depending Upon Varieties. The Highest Germination Was Obtained Under Laboratory And Greenhouse Condition By The Treatment Of Peg 200 G L-1 On The Situbagendit And Ir-64 Variety 90.25 And 93.33 Respectively Compared To Control In Inpago-8 In Both Laboratory 75.75 And Greenhouse 80 . As Implementation To Increase Seed And Seedling Vigor Of Rice It Is A Best Practice To Use Peg Priming With 200 Gl-1 Solutions Depend Upon Varietal Response And We Suggest That More Research About The Effect Of Peg As Seed Priming Techniques On Seed Germination Behavior Of Many Grain Crops Is Needed To Confirm The Methodology.

  1. Improvement of efficient in vitro regeneration potential of mature callus induced from Malaysian upland rice seed (Oryza sativa cv. Panderas).

    Science.gov (United States)

    Mohd Din, Abd Rahman Jabir; Iliyas Ahmad, Fauziah; Wagiran, Alina; Abd Samad, Azman; Rahmat, Zaidah; Sarmidi, Mohamad Roji

    2016-01-01

    A new and rapid protocol for optimum callus production and complete plant regeneration has been assessed in Malaysian upland rice (Oryza sativa) cv. Panderas. The effect of plant growth regulator (PGR) on the regeneration frequency of Malaysian upland rice (cv. Panderas) was investigated. Mature seeds were used as a starting material for callus induction experiment using various concentrations of 2,4-D and NAA. Optimal callus induction frequency at 90% was obtained on MS media containing 2,4-D (3 mg L(-1)) and NAA (2 mg L(-1)) after 6 weeks while no significant difference was seen on tryptophan and glutamine parameters. Embryogenic callus was recorded as compact, globular and light yellowish in color. The embryogenic callus morphology was further confirmed with scanning electron microscopy (SEM) analysis. For regeneration, induced calli were treated with various concentrations of Kin (0.5-1.5 mg L(-1)), BAP, NAA and 0.5 mg L(-1) of TDZ. The result showed that the maximum regeneration frequency (100%) was achieved on MS medium containing BAP (0.5 mg L(-1)), Kin (1.5 mg L(-1)), NAA (0.5 mg L(-1)) and TDZ (0.5 mg L(-1)) within four weeks. Developed shoots were successfully rooted on half strength MS free hormone medium and later transferred into a pot containing soil for acclimatization. This cutting-edge finding is unique over the other existing publishable data due to the good regeneration response by producing a large number of shoots.

  2. [Effect of selenium on the uptake and translocation of manganese, iron, phosphorus and selenium in rice (Oryza sativa L.)].

    Science.gov (United States)

    Hu, Ying; Huang, Yi-Zong; Huang, Yan-Chao; Liu, Yun-Xia; Liang, Jian-Hong

    2013-10-01

    A pot experiment was conducted to clarify the effect of selenium on the uptake and translocation of manganese (Mn), iron (Fe) , phosphorus (P) and selenium (Se) in rice ( Oryza sativa L.). The results showed that addition of Se led to the significant increase of Se concentration in iron plaque on the root surface, root, shoot, husk and brown rice, and significant decrease of Mn concentration in shoot, husk and brown rice. At the Se concentrations of 0.5 and 1.0 mg.kg-1 in soil, Mn concentrations in rice shoot decreased by 32. 2% and 35.0% respectively, in husk 22.0% and 42.6% , in brown rice 27.5% and 28.5% , compared with the Se-free treatment. There was no significant effect of Se on the P and Fe concentrations in every parts of rice, except for Fe concentrations in husk. The translocation of P and Fe from iron plaque, root, shoot and husk to brown rice was not significantly affected by Se addition, but Mn translocation from iron plaque and root to brown rice was significantly inhibited by Se addition. Addition of 1.0 mg.kg-1. Se resulted in the decrease of translocation factor from iron plaque and root to brown rice by 38.9% and 37.9%, respectively, compared with the control treatment. The distribution ratios of Mn, Fe, P and Se in iron plaque, root, shoot, husk and brown rice were also affected by Se addition. The results indicated that Mn uptake, accumulation and translocation in rice could be decreased by the addition of Se in soil, therefore, Se addition could reduce the Mn harm to human health through food chain.

  3. [Quantifying rice (Oryza sativa L.) photo-assimilated carbon input into soil organic carbon pools following continuous 14C labeling].

    Science.gov (United States)

    Nie, San-An; Zhou, Ping; Ge, Ti-Da; Tong, Cheng-Li; Xiao, He-Ai; Wu, Jin-Shui; Zhang, Yang-Zhu

    2012-04-01

    The microcosm experiment was carried out to quantify the input and distribution of photo-assimilated C into soil C pools by using a 14C continuous labeling technique. Destructive samplings of rice (Oryza sativa) were conducted after labeling for 80 days. The allocation of 14C-labeled photosynthates in plants and soil C pools such as dissolved organic C (DOC) and microbial biomass C (MBC) in rice-planted soil were examined over the 14C labeling span. The amounts of rice shoot and root biomass C was ranged from 1.86 to 5.60 g x pot(-1), 0.46 to 0.78 g x pot(-1) in different tested paddy soils after labeling for 80 days, respectively. The amount of 14C in the soil organic C (14C-SOC) was also dependent on the soils, ranged from 114.3 to 348.2 mg x kg(-1), accounting for 5.09% to 6.62% of the rice biomass 14C, respectively. The amounts of 14C in the dissolved organic C (14C-DOC) and in the microbial biomass C(14C-MBC), as proportions of 14C-SOC, were 2.21%-3.54% and 9.72% -17.2%, respectively. The 14C-DOC, 14C-MBC, and 14C-SOC as proportions of total DOC, MBC, and SOC, respectively, were 6.72% -14.64%, 1.70% -7.67%, and 0.73% -1.99%, respectively. Moreover, the distribution and transformation of root-derived C had a greater influence on the dynamics of DOC and MBC than on the dynamics of SOC. Further studies are required to ascertain the functional significance of soil microorganisms (such as C-sequestering bacteria and photosynthetic bacteria) in the paddy system.

  4. The Organelle Genomes of Hassawi Rice (Oryza sativa L.) and Its Hybrid in Saudi Arabia: Genome Variation, Rearrangement, and Origins

    Science.gov (United States)

    Zhang, Tongwu; Hu, Songnian; Zhang, Guangyu; Pan, Linlin; Zhang, Xiaowei; Al-Mssallem, Ibrahim S.; Yu, Jun

    2012-01-01

    Hassawi rice (Oryza sativa L.) is a landrace adapted to the climate of Saudi Arabia, characterized by its strong resistance to soil salinity and drought. Using high quality sequencing reads extracted from raw data of a whole genome sequencing project, we assembled both chloroplast (cp) and mitochondrial (mt) genomes of the wild-type Hassawi rice (Hassawi-1) and its dwarf hybrid (Hassawi-2). We discovered 16 InDels (insertions and deletions) but no SNP (single nucleotide polymorphism) is present between the two Hassawi cp genomes. We identified 48 InDels and 26 SNPs in the two Hassawi mt genomes and a new type of sequence variation, termed reverse complementary variation (RCV) in the rice cp genomes. There are two and four RCVs identified in Hassawi-1 when compared to 93–11 (indica) and Nipponbare (japonica), respectively. Microsatellite sequence analysis showed there are more SSRs in the genic regions of both cp and mt genomes in the Hassawi rice than in the other rice varieties. There are also large repeats in the Hassawi mt genomes, with the longest length of 96,168 bp and 96,165 bp in Hassawi-1 and Hassawi-2, respectively. We believe that frequent DNA rearrangement in the Hassawi mt and cp genomes indicate ongoing dynamic processes to reach genetic stability under strong environmental pressures. Based on sequence variation analysis and the breeding history, we suggest that both Hassawi-1 and Hassawi-2 originated from the Indonesian variety Peta since genetic diversity between the two Hassawi cultivars is very low albeit an unknown historic origin of the wild-type Hassawi rice. PMID:22870184

  5. The imprints of the high light and UV-B stresses in Oryza sativa L. 'Kanchana' seedlings are differentially modulated.

    Science.gov (United States)

    Faseela, Parammal; Puthur, Jos T

    2018-01-01

    High light and ultraviolet-B radiation (UV-B) are generally considered to have negative impact on photosynthesis and plant growth. The present study evaluates the tolerance potential of three cultivars of Oryza sativa L. (Kanchana, Mattatriveni and Harsha) seedlings towards high light and UV-B stress on the basis of photosynthetic pigment degradation, chlorophyll a fluorescence parameters and rate of lipid peroxidation, expressed by malondialdehyde content. Surprisingly, it was revealed that Kanchana was the most sensitive cultivar towards high light and at the same time it was the most tolerant cultivar towards UV-B stress. This contrasting feature of Kanchana towards high light and UV-B tolerance was further studied by analyzing photosystem (PS) I and II activity, mitochondrial activity, chlorophyll a fluorescence transient, enzymatic and non-enzymatic antioxidant defense system. Due to the occurrence of more PS I and PSII damages, the inhibition of photochemical efficiency and emission of dissipated energy as heat or fluorescence per PSII reaction center was higher upon high light exposure than UV-B treatments in rice seedlings of Kanchana. The mitochondrial activity was also found to be drastically altered upon high light as compared to UV-B treatments. The UV-B induced accumulation of non-enzymatic antioxidants (proline, total phenolics, sugar and ascorbate) and enzymatic antioxidants (ascorbate peroxidase, guaiacol peroxidase, superoxide dismutase and glutathione reductase) in rice seedlings than those subjected to high light exposure afforded more efficient protection against UV-B radiation in rice seedlings. Our results proved that high tolerance of Kanchana towards UV-B than high light treatments, correlated linearly with the protected photosynthetic and mitochondrial machinery which was provided by upregulation of antioxidants particularly by total phenolics, ascorbate and ascorbate peroxidase in rice seedlings. Data presented in this study conclusively

  6. Inhibition of cadmium ion uptake in rice (Oryza sativa) cells by a wall-bound form of silicon.

    Science.gov (United States)

    Liu, Jian; Ma, Jie; He, Congwu; Li, Xiuli; Zhang, Wenjun; Xu, Fangsen; Lin, Yongjun; Wang, Lijun

    2013-11-01

    The stresses acting on plants that are alleviated by silicon (Si) range from biotic to abiotic stresses, such as heavy metal toxicity. However, the mechanism of stress alleviation by Si at the single-cell level is poorly understood. We cultivated suspended rice (Oryza sativa) cells and protoplasts and investigated them using a combination of plant nutritional and physical techniques including inductively coupled plasma mass spectrometry (ICP-MS), the scanning ion-selective electrode technique (SIET) and X-ray photoelectron spectroscopy (XPS). We found that most Si accumulated in the cell walls in a wall-bound organosilicon compound. Total cadmium (Cd) concentrations in protoplasts from Si-accumulating (+Si) cells were significantly reduced at moderate concentrations of Cd in the culture medium compared with those from Si-limiting (-Si) cells. In situ measurement of cellular fluxes of the cadmium ion (Cd(2+) ) in suspension cells and root cells of rice exposed to Cd(2+) and/or Si treatments showed that +Si cells significantly inhibited the net Cd(2+) influx, compared with that in -Si cells. Furthermore, a net negative charge (charge density) within the +Si cell walls could be neutralized by an increase in the Cd(2+) concentration in the measuring solution. A mechanism of co-deposition of Si and Cd in the cell walls via a [Si-wall matrix]Cd co-complexation may explain the inhibition of Cd ion uptake, and may offer a plausible explanation for the in vivo detoxification of Cd in rice. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  7. Copper and ectopic expression of the Arabidopsis transport protein COPT1 alter iron homeostasis in rice (Oryza sativa L.).

    Science.gov (United States)

    Andrés-Bordería, Amparo; Andrés, Fernando; Garcia-Molina, Antoni; Perea-García, Ana; Domingo, Concha; Puig, Sergi; Peñarrubia, Lola

    2017-09-01

    Copper deficiency and excess differentially affect iron homeostasis in rice and overexpression of the Arabidopsis high-affinity copper transporter COPT1 slightly increases endogenous iron concentration in rice grains. Higher plants have developed sophisticated mechanisms to efficiently acquire and use micronutrients such as copper and iron. However, the molecular mechanisms underlying the interaction between both metals remain poorly understood. In the present work, we study the effects produced on iron homeostasis by a wide range of copper concentrations in the growth media and by altered copper transport in Oryza sativa plants. Gene expression profiles in rice seedlings grown under copper excess show an altered expression of genes involved in iron homeostasis compared to standard control conditions. Thus, ferritin OsFER2 and ferredoxin OsFd1 mRNAs are down-regulated whereas the transcriptional iron regulator OsIRO2 and the nicotianamine synthase OsNAS2 mRNAs rise under copper excess. As expected, the expression of OsCOPT1, which encodes a high-affinity copper transport protein, as well as other copper-deficiency markers are down-regulated by copper. Furthermore, we show that Arabidopsis COPT1 overexpression (C1 OE ) in rice causes root shortening in high copper conditions and under iron deficiency. C1 OE rice plants modify the expression of the putative iron-sensing factors OsHRZ1 and OsHRZ2 and enhance the expression of OsIRO2 under copper excess, which suggests a role of copper transport in iron signaling. Importantly, the C1 OE rice plants grown on soil contain higher endogenous iron concentration than wild-type plants in both brown and white grains. Collectively, these results highlight the effects of rice copper status on iron homeostasis, which should be considered to obtain crops with optimized nutrient concentrations in edible parts.

  8. Enhanced resistance to blast fungus in rice (Oryza sativa L.) by expressing the ribosome-inactivating protein α-momorcharin.

    Science.gov (United States)

    Qian, Qian; Huang, Lin; Yi, Rong; Wang, Shuzhen; Ding, Yi

    2014-03-01

    Rice blast caused by Magnaporthe grisea is one of the three major diseases that seriously affect the rice production. Alpha-momorcharin (α-MC), a ribosome-inactivating protein (RIP) isolated from Momordica charantia seeds, has antifungal effects in vitro. In this study, the α-MC gene was constitutively expressed under the control of the 2×35S promoter in transgenic rice (Oryza sativa L.) using an Agrobacterium tumefaciens-mediated method. The nine transgenic plants were obtained and confirmed by PCR and RT-PCR, and the four (B2, B4, B7 and B9) of them whose copy numbers were 1, 2, 3 and 3, respectively, were shown to express the α-MC protein by Western blot. The molecular weight of α-MC in transgenic plants was approximately 38 kDa larger than the purified α-MC protein (28 kDa) in vitro. When the confirmed T1 generations were inoculated with a suspension of M. grisea spores for ten days, the lesions on leaves of transgenic plants were much lesser than those found on wild type (WT). According to the criteria of International Rice Research Institute standard, the mean values for morbidity and disease index numbers were 29.8% and 14.9%, respectively, which were lower than for WT. It is unclear whether RIPs could impact plant fitness and however our results suggest that the α-MC protein is an effective antifungal protein preventing rice blast in transgenic rice. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. In silico Allergenicity Study of Insect resistant genetically Modified Rice (Oryza sativa L. for assessment of biosafety

    Directory of Open Access Journals (Sweden)

    S.K. Das

    2017-12-01

    Full Text Available India is one of the world's largest producers of rice (Oryza sativa, accounting for 20% of all world rice production. However, lepidopteran pests severely impact the harvest of rice, which leads to environmental pollution and increase production cost. Alternatively, genetic engineering methods may be used to prevent rice pests and increase production of rice in a safe and environmentally friendly manner. Bacillus thuringiensis (Bt genes have been widely used to generate genetically modified (GM crops because the expressed cry1Ab protein confers resistance to lepidopteron pests. The proteins expressed by these genes may lead to food safety problems. Thus, safety evaluations are necessary prior to commercialization. Bioinformatics analysis for allergenicity assessment of cry1Ab protein is performed using different allergen databases viz. FARRP SDAP, Allergome, and Algpred to identify any potential sequence matches to allergen proteins that might indicate allergenic cross-reactivity with the query sequence. A full FASTA search was performed to identify highly similar proteins. However; the full length search cannot identify discontinuous or conformational epitopes that depend upon the tertiary structure of the protein.So every possible contiguous 80-amino acid sequence of each query protein was searched for determining the similarity. The proteins sequence can be searched using FASTA/BLAST for broad homology to known allergens to identify any short sequence that might represent an allergenic epitope. The domains in the Cry protein sequences were searched using Interproscan for potential similarity at the domain level. The results showed neither significant alignment nor similarity of cry1Ab protein at full sequence, domain, and epitope level with any of the known allergen proteins in the full sequence matching. Matching the 80 amino acid and matching of 8 amino acids showed no similarity to determine the epitope potential. From literature survey

  10. Root Associated Bacillus sp. Improves Growth, Yield and Zinc Translocation for Basmati Rice (Oryza sativa) Varieties

    Science.gov (United States)

    Shakeel, Muhammad; Rais, Afroz; Hassan, Muhammad Nadeem; Hafeez, Fauzia Yusuf

    2015-01-01

    Plant associated rhizobacteria prevailing in different agro-ecosystems exhibit multiple traits which could be utilized in various aspect of sustainable agriculture. Two hundred thirty four isolates were obtained from the roots of basmati-385 and basmati super rice varieties growing in clay loam and saline soil at different locations of Punjab (Pakistan). Out of 234 isolates, 27 were able to solubilize zinc (Zn) from different Zn ores like zinc phosphate [Zn3 (PO4)2], zinc carbonate (ZnCO3) and zinc oxide (ZnO). The strain SH-10 with maximum Zn solubilization zone of 24 mm on Zn3 (PO4)2ore and strain SH-17 with maximum Zn solubilization zone of 14–15 mm on ZnO and ZnCO3ores were selected for further studies. These two strains solubilized phosphorous (P) and potassium (K) in vitro with a solubilization zone of 38–46 mm and 47–55 mm respectively. The strains also suppressed economically important rice pathogens Pyricularia oryzae and Fusarium moniliforme by 22–29% and produced various biocontrol determinants in vitro. The strains enhanced Zn translocation toward grains and increased yield of basmati-385 and super basmati rice varieties by 22–49% and 18–47% respectively. The Zn solubilizing strains were identified as Bacillus sp. and Bacillus cereus by 16S rRNA gene analysis. PMID:26635754

  11. Physiological basis of genetic variation in leaf photosynthesis among rice (Oryza sativa L.) introgression lines under drought and well-watered conditions

    Science.gov (United States)

    Yin, Xinyou

    2012-01-01

    To understand the physiological basis of genetic variation and resulting quantitative trait loci (QTLs) for photosynthesis in a rice (Oryza sativa L.) introgression line population, 13 lines were studied under drought and well-watered conditions, at flowering and grain filling. Simultaneous gas exchange and chlorophyll fluorescence measurements were conducted at various levels of incident irradiance and ambient CO2 to estimate parameters of a model that dissects photosynthesis into stomatal conductance (g s), mesophyll conductance (g m), electron transport capacity (J max), and Rubisco carboxylation capacity (V cmax). Significant genetic variation in these parameters was found, although drought and leaf age accounted for larger proportions of the total variation. Genetic variation in light-saturated photosynthesis and transpiration efficiency (TE) were mainly associated with variation in g s and g m. One previously mapped major QTL of photosynthesis was associated with variation in g s and g m, but also in J max and V cmax at flowering. Thus, g s and g m, which were demonstrated in the literature to be responsible for environmental variation in photosynthesis, were found also to be associated with genetic variation in photosynthesis. Furthermore, relationships between these parameters and leaf nitrogen or dry matter per unit area, which were previously found across environmental treatments, were shown to be valid for variation across genotypes. Finally, the extent to which photosynthesis rate and TE can be improved was evaluated. Virtual ideotypes were estimated to have 17.0% higher photosynthesis and 25.1% higher TE compared with the best genotype investigated. This analysis using introgression lines highlights possibilities of improving both photosynthesis and TE within the same genetic background. PMID:22888131

  12. Interactions of rice (Oryza sativa L.) and PAH-degrading bacteria (Acinetobacter sp.) on enhanced dissipation of spiked phenanthrene and pyrene in waterlogged soil.

    Science.gov (United States)

    Gao, Y; Yu, X Z; Wu, S C; Cheung, K C; Tam, N F Y; Qian, P Y; Wong, M H

    2006-12-15

    The effects of cultivation of rice (Oryza sativa L.) and PAH-degrading bacteria (Acinetobacter sp.) separately, and in combination, on the dissipation of spiked phenanthrene and pyrene (0, 50+50, 100+100, 200+200 mg kg(-1)) in waterlogged soil were studied using pot trials. The population of introduced PAH-degrading bacteria remained at 10(5) CFU g(-1) dry soil after 20 days of treatment with Acinetobacter sp. only, but increased to 10(6) when planted with rice simultaneously. Shoot and root biomass of rice when grown alone was adversely affected by spiked PAHs, but significantly increased by 2-55% and 8-409%, respectively, when inoculated with Acinetobacter sp.. Phenanthrene and pyrene concentrations in roots ranged from 1-27 and 20-98 mg kg(-1), respectively, while their concentrations in shoots were generally lower than 0.2 mg kg(-1). The dissipation of phenanthrene was mainly due to abiotic loss as 70-78% phenanthrene was lost from the control soil at the end of 80 days, while removal of 86-87% phenanthrene had been achieved after 40 days in the treatment co-cultivated with Acinetobacter sp. and rice. Compared with the control where only 6-15% of pyrene was removed from soil, a much higher dissipation of pyrene (43-62%) was attained for the treatments co-cultivated with Acinetobacter sp. and rice at the end of 80 days. The results demonstrated that co-cultivation of rice and PAH-degrading bacteria may have a great potential to accelerate the bioremediation process of PAH-contaminated soil under waterlogged conditions.

  13. Reconstruction of Oryza sativa indica Genome Scale Metabolic Model and Its Responses to Varying RuBisCO Activity, Light Intensity, and Enzymatic Cost Conditions

    Directory of Open Access Journals (Sweden)

    Ankita Chatterjee

    2017-11-01

    Full Text Available To combat decrease in rice productivity under different stresses, an understanding of rice metabolism is needed. Though there are different genome scale metabolic models (GSMs of Oryza sativa japonica, no GSM with gene-protein-reaction association exist for Oryza sativa indica. Here, we report a GSM, OSI1136 of O.s. indica, which includes 3602 genes and 1136 metabolic reactions and transporters distributed across the cytosol, mitochondrion, peroxisome, and chloroplast compartments. Flux balance analysis of the model showed that for varying RuBisCO activity (Vc/Vo (i the activity of the chloroplastic malate valve increases to transport reducing equivalents out of the chloroplast under increased photorespiratory conditions and (ii glyceraldehyde-3-phosphate dehydrogenase and phosphoglycerate kinase can act as source of cytosolic ATP under decreased photorespiration. Under increasing light conditions we observed metabolic flexibility, involving photorespiration, chloroplastic triose phosphate and the dicarboxylate transporters of the chloroplast and mitochondrion for redox and ATP exchanges across the intracellular compartments. Simulations under different enzymatic cost conditions revealed (i participation of peroxisomal glutathione-ascorbate cycle in photorespiratory H2O2 metabolism (ii different modes of the chloroplastic triose phosphate transporters and malate valve, and (iii two possible modes of chloroplastic Glu–Gln transporter which were related with the activity of chloroplastic and cytosolic isoforms of glutamine synthetase. Altogether, our results provide new insights into plant metabolism.

  14. Role of hydroperoxide lyase in white-backed planthopper (Sogatella furcifera Horváth)-induced resistance to bacterial blight in rice, Oryza sativa L.

    Science.gov (United States)

    Gomi, Kenji; Satoh, Masaru; Ozawa, Rika; Shinonaga, Yumi; Sanada, Sachiyo; Sasaki, Katsutomo; Matsumura, Masaya; Ohashi, Yuko; Kanno, Hiroo; Akimitsu, Kazuya; Takabayashi, Junji

    2010-01-01

    A pre-infestation of the white-backed planthopper (WBPH), Sogatella furcifera Horváth, conferred resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo) in rice (Oryza sativa L.) under both laboratory and field conditions. The infestation of another planthopper species, the brown planthopper (BPH) Nilaparvata lugens Stål, did not significantly reduce the incidence of bacterial blight symptoms. A large-scale screening using a rice DNA microarray and quantitative RT-PCR revealed that WBPH infestation caused the upregulation of more defence-related genes than did BPH infestation. Hydroperoxide lyase 2 (OsHPL2), an enzyme for producing C(6) volatiles, was upregulated by WBPH infestation, but not by BPH infestation. One C(6) volatile, (E)-2-hexenal, accumulated in rice after WBPH infestation, but not after BPH infestation. A direct application of (E)-2-hexenal to a liquid culture of Xoo inhibited the growth of the bacterium. Furthermore, a vapour treatment of rice plants with (E)-2-hexenal induced resistance to bacterial blight. OsHPL2-overexpressing transgenic rice plants exhibited increased resistance to bacterial blight. Based on these data, we conclude that OsHPL2 and its derived (E)-2-hexenal play some role in WBPH-induced resistance in rice.

  15. Effects of timing and severity of salinity stress on rice (Oryza sativa L.) yield, grain composition, and starch functionality.

    Science.gov (United States)

    Thitisaksakul, Maysaya; Tananuwong, Kanitha; Shoemaker, Charles F; Chun, Areum; Tanadul, Orn-u-ma; Labavitch, John M; Beckles, Diane M

    2015-03-04

    The aim of this work was to examine agronomic, compositional, and functional changes in rice (Oryza sativa L. cv. Nipponbare) grains from plants grown under low-to-moderate salinity stress in the greenhouse. Plants were grown in sodium chloride-containing soil (2 or 4 dS/m(2) electrical conductivity), which was imposed 4-weeks after transplant (called Seedling EC2 and EC4) or after the appearance of the anthers (called Anthesis EC2 and EC4). The former simulates field conditions while the latter permits observation of the isolated effect of salt on grain filling processes. Key findings of this study are the following: (i) Plants showed adaptive responses to prolonged salt treatment with no negative effects on grain weight or fertility. Seedling EC2 plants had more panicles and enhanced caryopsis dimensions, while surprisingly, Seedling EC4 plants did not differ from the control group in the agronomic parameters measured. (ii) Grain starch increased in Seedling EC4 (32.6%) and Anthesis EC2 (39%), respectively, suggesting a stimulatory effect of salt on starch accumulation. (iii) The salinity treatment of 2 dS/m(2) was better tolerated at anthesis than the 4 dS/m(2) treatment as the latter led to reduced grain weight (28.8%) and seed fertility (19.4%) and compensatory increases in protein (20.1%) and nitrogen (19.8%) contents. (iv) Although some salinity treatments led to changes in starch content, these did not alter starch fine structure, morphology, or composition. We observed no differences in reducing sugar and amylose content or starch granule size distribution among any of the treatments. The only alterations in starch were limited to small changes in thermal properties and glucan chain distribution, which were only seen in the Anthesis EC4 treatment. This similarity of compositional and functional features was supported by multivariate analysis of all variables measured, which suggested that differences due to treatments were minimal. Overall, this study

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

    Science.gov (United States)

    Singh, Kamal Krishna; Ghosh, Shilpi

    2013-02-01

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

  17. microRNAs targeting DEAD-box helicases are involved in salinity stress response in rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Macovei Anca

    2012-10-01

    Full Text Available Abstract Background Rice (Oryza sativa L., one of the most important food crop in the world, is considered to be a salt-sensitive crop. Excess levels of salt adversely affect all the major metabolic activities, including cell wall damage, cytoplasmic lysis and genomic stability. In order to cope with salt stress, plants have evolved high degrees of developmental plasticity, including adaptation via cascades of molecular networks and changes in gene expression profiles. Posttranscriptional regulation, through the activity of microRNAs, also plays an important role in the plant response to salinity conditions. MicroRNAs are small endogenous RNAs that modulate gene expression and are involved in the most essential physiological processes, including plant development and adaptation to environmental changes. Results In the present study, we investigated the expression profiles of osa-MIR414, osa-MIR408 and osa-MIR164e along with their targeted genes, under salinity stress conditions in wild type and transgenic rice plants ectopically expressing the PDH45 (Pea DNA Helicase gene. The present miRNAs were predicted to target the OsABP (ATP-Binding Protein, OsDSHCT (DOB1/SK12/helY-like DEAD-box Helicase and OsDBH (DEAD-Box Helicase genes, included in the DEAD-box helicase family. An in silico characterization of the proteins was performed and the miRNAs predicted targets were validated by RLM-5′RACE. The qRT-PCR analysis showed that the OsABP, OsDBH and OsDSHCT genes were up-regulated in response to 100 and 200 mM NaCl treatments. The present study also highlighted an increased accumulation of the gene transcripts in wild type plants, with the exception of the OsABP mRNA which showed the highest level (15.1-fold change compared to control in the transgenic plants treated with 200 mM NaCl. Salinity treatments also affected the expression of osa-MIR414, osa-MIR164e and osa-MIR408, found to be significantly down-regulated, although the changes in mi

  18. Monitoring expression profiles of rice (Oryza sativa L.) genes under abiotic stresses using cDNA Microarray Analysis (abstract)

    International Nuclear Information System (INIS)

    Rabbani, M.A.

    2005-01-01

    Transcript regulation in response to cold, drought, high salinity and ABA application was investigated in rice (Oryza sativa L., Nipponbare) with microarray analysis including approx. 1700 independent DNA elements derived from three cDNA libraries constructed from 15-day old rice seedlings stressed with drought, cold and high salinity. A total of 141 non-redundant genes were identified, whose expression ratios were more than three-fold compared with the control genes for at least one of stress treatments in microarray analysis. However, after RNA gel blot analysis, a total of 73 genes were identified, among them the transcripts of 36, 62, 57 and 43 genes were found increased after cold, drought, high salinity and ABA application, respectively. Sixteen of these identified genes have been reported previously to be stress inducible in rice, while 57 of which are novel that have not been reported earlier as stress responsive in rice. We observed a strong association in the expression patterns of stress responsive genes and found 15 stress inducible genes that responded to all four treatments. Based on Venn diagram analysis, 56 genes were induced by both drought and high salinity, whereas 22 genes were upregulated by both cold and high salinity stress. Similarly 43 genes were induced by both drought stress and ABA application, while only 17 genes were identified as cold and ABA inducible genes. These results indicated the existence of greater cross talk between drought, ABA and high salinity stress signaling processes than those between cold and ABA, and cold and high salinity stress signaling pathways. The cold, drought, high salinity and ABA inducible genes were classified into four gene groups from their expression profiles. Analysis of data enabled us to identify a number of promoters and possible cis-acting DNA elements of several genes induced by a variety of abiotic stresses by combining expression data with genomic sequence data of rice. Comparative analysis of

  19. Concentrations of arsenic and lead in rice (Oryza sativa L.) in Iran: A systematic review and carcinogenic risk assessment.

    Science.gov (United States)

    Fakhri, Yadolah; Bjørklund, Geir; Bandpei, Anoushiravan Mohseni; Chirumbolo, Salvatore; Keramati, Hassan; Hosseini Pouya, Rokhsane; Asadi, Anvar; Amanidaz, Nazak; Sarafraz, Mansour; Sheikhmohammad, Amir; Alipour, Mohamadreza; Baninameh, Zahra; Mohseni, Seyed Mohsen; Sarkhosh, Maryam; Ghasemi, Seyed Mehdi

    2018-03-01

    Exposure to heavy metals such as arsenic (As), lead (Pb), and cadmium (Cd) in either the short or the long term can cause cancers in humans. Dietary intake and consumption of rice (Oryza sativa L.) is increasing in Iran, and several studies on the concentration of heavy metals in rice have been carried out in this country in recent years. In this perspective, the main objective of the present study was to investigate, even via a meta-analysis of the existing literature, the presence of As and Pb in rice from many geographical areas in Iran, as well as to estimate the carcinogenic risk of these heavy metals in rice consumers. The results of the present ten years-spanning systematic review indicate that 21 reports, collecting a total of 2088 samples, were performed between 2008 and October 2017. The minimum and maximum concentration of As was observed in the Golestan area (0.01 ± 0.01 mg/kg d.w) and the Gillan region (3 mg/kg d.w); and Pb in the Shahrekord (0.07 ± 0.02 mg/kg d.w) and Mazandaran (35 mg/kg d.w). The meta-analysis of data showed that pooled concentration of As in the rice was 0.04 (95%CI: 0.02-0.06 mg/kg d.w), which resulted lower than the National Standard (NS) limits. However, the pooled concentration of Pb in the rice was 0.38 (95%CI: 0.25-0.5 mg/kg d.w), i.e., higher than NS limits. The heterogeneity was significant between As (I 2  = 63%, P value = .003) and Pb (I 2  = 96%, P value rice content of As and Pb are at considerable carcinogenesis risk (ILCR > 10 -3 ). Therefore a decreased level of heavy metals in rice cultivation should be encouraged and performed in next planning. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. A rapid mini-prep DNA extraction method in rice (Oryza sativa)

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-19

    Jan 19, 2009 ... homogenizer with a plastic tip is incomplete, since the leaves of these plants .... mortar and pestle with liquid nitrogen and transferred to a tube. ... rapid DNA extraction protocols for gymnosperms for application in population ...

  1. Analysis of nucleotide diversity among alleles of the major bacterial blight resistance gene Xa27 in cultivars of rice (Oryza sativa) and its wild relatives.

    Science.gov (United States)

    Bimolata, Waikhom; Kumar, Anirudh; Sundaram, Raman Meenakshi; Laha, Gouri Shankar; Qureshi, Insaf Ahmed; Reddy, Gajjala Ashok; Ghazi, Irfan Ahmad

    2013-08-01

    Xa27 is one of the important R-genes, effective against bacterial blight disease of rice caused by Xanthomonas oryzae pv. oryzae (Xoo). Using natural population of Oryza, we analyzed the sequence variation in the functionally important domains of Xa27 across the Oryza species. DNA sequences of Xa27 alleles from 27 rice accessions revealed higher nucleotide diversity among the reported R-genes of rice. Sequence polymorphism analysis revealed synonymous and non-synonymous mutations in addition to a number of InDels in non-coding regions of the gene. High sequence variation was observed in the promoter region including the 5'UTR with 'π' value 0.00916 and 'θ w ' = 0.01785. Comparative analysis of the identified Xa27 alleles with that of IRBB27 and IR24 indicated the operation of both positive selection (Ka/Ks > 1) and neutral selection (Ka/Ks ≈ 0). The genetic distances of alleles of the gene from Oryza nivara were nearer to IRBB27 as compared to IR24. We also found the presence of conserved and null UPT (upregulated by transcriptional activator) box in the isolated alleles. Considerable amino acid polymorphism was localized in the trans-membrane domain for which the functional significance is yet to be elucidated. However, the absence of functional UPT box in all the alleles except IRBB27 suggests the maintenance of single resistant allele throughout the natural population.

  2. Tagging of four Rf genes with selective genotyping analysis in rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Yarahmadi Saeid

    2017-01-01

    Full Text Available Wild abortive type of cytoplasmic male sterility (WA-CMS is commercially used for hybrid rice seed production. The linked markers can be used for selection of plants with desirable traits. Tagging of Rf genes was carried out using recessive and dominant class analysis in a large F2 population from the cross IR58025A×IR42686R. Pollen fertility and seed setting were evaluated at the flowering and maturity stages, respectively. Forty-seven highly sterile and 23 fertile homozygous plants were selected from F2 population for molecular marker assay. Four Rf genes identified in a good restorer line with high-quality derived from a random mating composite population at the International Rice Research Institute (IRRI. The genetic distance from Rf3 locus with flanking markers RM443 and RM315 on chromosome 1 was 3.7 and 21.2 cM, respectively. RM258, RM591, RM271 and RM6737 on the long arm of chromosome 10 were linked with the Rf6 gene with distance of 7.4, 22.6, 6 and 2.9 cM, respectively. Rf6 was flanked by RM6737 and RM591. The Rf4 gene located on chromosome 7 was linked with RM6344 at a genetic distance of 10.6 cM. RM519 and RM7003 were linked with other Rf gene on chromosome 12 at a genetic distance of 8.5 and 20.8 cM, respectively. Closely linked markers identified in this study could be used for marker assisted selection in a hybrid rice breeding program. A new Rf locus on chromosome 12 that designated Rf7 was linked with RM7003 and RM519.

  3. Isolation of a novel mutant gene for soil-surface rooting in rice (Oryza sativa L.).

    Science.gov (United States)

    Hanzawa, Eiko; Sasaki, Kazuhiro; Nagai, Shinsei; Obara, Mitsuhiro; Fukuta, Yoshimichi; Uga, Yusaku; Miyao, Akio; Hirochika, Hirohiko; Higashitani, Atsushi; Maekawa, Masahiko; Sato, Tadashi

    2013-11-20

    Root system architecture is an important trait affecting the uptake of nutrients and water by crops. Shallower root systems preferentially take up nutrients from the topsoil and help avoid unfavorable environments in deeper soil layers. We have found a soil-surface rooting mutant from an M2 population that was regenerated from seed calli of a japonica rice cultivar, Nipponbare. In this study, we examined the genetic and physiological characteristics of this mutant. The primary roots of the mutant showed no gravitropic response from the seedling stage on, whereas the gravitropic response of the shoots was normal. Segregation analyses by using an F2 population derived from a cross between the soil-surface rooting mutant and wild-type Nipponbare indicated that the trait was controlled by a single recessive gene, designated as sor1. Fine mapping by using an F2 population derived from a cross between the mutant and an indica rice cultivar, Kasalath, revealed that sor1 was located within a 136-kb region between the simple sequence repeat markers RM16254 and 2935-6 on the terminal region of the short arm of chromosome 4, where 13 putative open reading frames (ORFs) were found. We sequenced these ORFs and detected a 33-bp deletion in one of them, Os04g0101800. Transgenic plants of the mutant transformed with the genomic fragment carrying the Os04g0101800 sequence from Nipponbare showed normal gravitropic responses and no soil-surface rooting. These results suggest that sor1, a rice mutant causing soil-surface rooting and altered root gravitropic response, is allelic to Os04g0101800, and that a 33-bp deletion in the coding region of this gene causes the mutant phenotypes.

  4. GENETICS OF BROWN PLANTHOPPER (NILAPARVATA LUGENS STAL.) RESISTANCE IN ELITE DONORS OF RICE (ORYZA SATIVA L.)

    OpenAIRE

    B BALAKRISHNA; P V SATAYANARAYANA

    2013-01-01

    The inheritance of resistance to the brown planthopper (BPH) in four BPH resistant donors of rice i. e., Sinna Sivappu, Sudu Hondarawala, PTB 33 and BM 71 was studied both in field and greenhouse conditions. The F2 population of crosses involving donors Sinna Sivappu, Sudu Hondarawala and PTB 33 fit into the ratio of 13:3 indicating the resistance to BPH was controlled by two genes i. e., one dominant and one recessive gene segregating independent to each other. The F2 populat...

  5. Improvement of photosynthesis in rice (Oryza sativa L.) by inserting the C4 pathway.

    Science.gov (United States)

    Karki, Shanta; Rizal, Govinda; Quick, William Paul

    2013-10-28

    To boost food production for a rapidly growing global population, crop yields must significantly increase. One of the avenues being recently explored is the improvement of photosynthetic capacity by installing the C4 photosynthetic pathway into C3 crops like rice to drastically increase their yield. Crops with an enhanced photosynthetic mechanism would better utilize the solar radiation that can be translated into yield. This subsequently will help in producing more grain yield, reduce water loss and increase nitrogen use efficiency especially in hot and dry environments. This review provides a summary of the factors that need to be modified in rice so that the C4 pathway can be introduced successfully. It also discusses the differences between the C3 and C4 photosynthetic pathways in terms of anatomy, biochemistry and genetics.

  6. Identification of dominant male sterile mutants in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Zhu Xudong; Rutger, J.N.

    2000-01-01

    Genetic male sterile mutants 1783 and 1789 were selected from US variety Orion and Kaybonnet seeds treated by gamma irradiation. Investigation of fertility characterization of pollen and spikelets of these mutants were made by progeny tests in 1783 M 7 and 1789 M 6 generations. The results showed that genetic male sterile mutants 1783 and 1789 with the fertility segregating of 1 sterile: 1 fertile were controlled by a single dominant gene. The pollen staining of mutants characterized partial sterility. Open-pollinated seed set was about 30% and bagged seed set was only 0.3%-3.5%. It is concluded that dominant genetic male sterile is a useful tool in improvement of population for rice breeding

  7. Metabolism and prebiotics activity of anthocyanins from black rice (Oryza sativa L.) in vitro.

    Science.gov (United States)

    Zhu, Yongsheng; Sun, Hanju; He, Shudong; Lou, Qiuyan; Yu, Min; Tang, Mingming; Tu, Lijun

    2018-01-01

    Anthocyanins are naturally active substances. In this study, anthocyanins from black rice were obtained by membrane filtration and column chromatography separation. Five anthocyanin monomers in black rice extract were identified by HPLC-MS/MS, and the major anthocyanin monomer (cyanidin-3-glucoside, C3G) was purified by preparative HPLC (Pre-HPLC). The proliferative effects of the anthocyanins on Bifidobacteria and Lactobacillus were investigated by determining the media pH, bacterial populations and metabolic products. After anaerobic incubation at 37 °C for 48 h, not only the pH of the media containing C3G was lower than that of the extract of black rice anthocyanin (BRAE), but the numbers of both Bifidobacteria and Lactobacillus were also significantly increased. Furthermore, hydroxyphenylpropionic, hydroxyphenylacetic, and hydroxybenzoic acids and other metabolites were detected by GC-MS in vitro. Our results revealed that the anthocyanins and anthocyanin monomers from black rice had prebiotic activity and they were metabolized into several small molecules by Bifidobacteria and Lactobacillus.

  8. Biallelic and Genome Wide Association Mapping of Germanium Tolerant Loci in Rice (Oryza sativa L..

    Directory of Open Access Journals (Sweden)

    Partha Talukdar

    Full Text Available Rice plants accumulate high concentrations of silicon. Silicon has been shown to be involved in plant growth, high yield, and mitigating biotic and abiotic stresses. However, it has been demonstrated that inorganic arsenic is taken up by rice through silicon transporters under anaerobic conditions, thus the ability to efficiently take up silicon may be considered either a positive or a negative trait in rice. Germanium is an analogue of silicon that produces brown lesions in shoots and leaves, and germanium toxicity has been used to identify mutants in silicon and arsenic transport. In this study, two different genetic mapping methods were performed to determine the loci involved in germanium sensitivity in rice. Genetic mapping in the biparental cross of Bala × Azucena (an F6 population and a genome wide association (GWA study with 350 accessions from the Rice Diversity Panel 1 were conducted using 15 μM of germanic acid. This identified a number of germanium sensitive loci: some co-localised with previously identified quantitative trait loci (QTL for tissue silicon or arsenic concentration, none co-localised with Lsi1 or Lsi6, while one single nucleotide polymorphism (SNP was detected within 200 kb of Lsi2 (these are genes known to transport silicon, whose identity was discovered using germanium toxicity. However, examining candidate genes that are within the genomic region of the loci detected above reveals genes homologous to both Lsi1 and Lsi2, as well as a number of other candidate genes, which are discussed.

  9. Association mapping for yield and grain quality traits in rice (Oryza sativa L.)

    Science.gov (United States)

    2010-01-01

    Association analysis was applied to a panel of accessions of Embrapa Rice Core Collection (ERiCC) with 86 SSR and field data from two experiments. A clear subdivision between lowland and upland accessions was apparent, thereby indicating the presence of population structure. Thirty-two accessions with admixed ancestry were identified through structure analysis, these being discarded from association analysis, thus leaving 210 accessions subdivided into two panels. The association of yield and grain-quality traits with SSR was undertaken with a mixed linear model, with markers and subpopulation as fixed factors, and kinship matrix as a random factor. Eight markers from the two appraised panels showed significant association with four different traits, although only one (RM190) maintained the marker-trait association across years and cultivation. The significant association detected between amylose content and RM190 was in agreement with previous QTL analyses in the literature. Herein, the feasibility of undertaking association analysis in conjunction with germplasm characterization was demonstrated, even when considering low marker density. The high linkage disequilibrium expected in rice lines and cultivars facilitates the detection of marker-trait associations for implementing marker assisted selection, and the mining of alleles related to important traits in germplasm. PMID:21637426

  10. Utilization of wastewater on seed germination and physioogical parameters of rice (Oryza sativa L.)

    Science.gov (United States)

    Huy, V.; Iwai, C. B.

    2018-03-01

    Due to increasing world population and demand, fresh water availability is becoming a limited resource. Reusing wastewater for agriculture has received attention since it contains nutrients, which are beneficial for growing crops. Even though wastewater can be used as the nutrient source for the plant, the toxicity of wastewater can still be a cause for concern and investigation. The main objective of this paper was to assess the effect of different sources of wastewater on the germination of Jasmine rice (KDML105), White rice (Phatum Thani 1), and Sticky rice (RD6) under laboratory conditions. Petri dish cultures were used with various concentrations (0, 50, and 100%) of wastewater collected from swine farm, aquaculture activity, and domestic. Seed germination, root length, shoot length, seed vigor index, fresh weight and dry weight were measured after each experiment. The results have shown that domestic wastewater and aquaculture activity wastewater did not decrease performance of Jasmine rice (KDML105), White rice (Phatum thani 1), and Sticky rice (RD6) while the germination of Jasmine rice (KDML105), White rice (Phatum thani 1), and Sticky rice (RD6) decreased when irrigated with swine farm wastewater. Therefore, using domestic and aquaculture activity wastewater for irrigation are suitable for growth of these crop.

  11. Biogenic synthesis, characterization of silver nanoparticles using multani mitti (fullers earth), tomato (solanum lycopersicum) seeds, rice husk (oryza sativa) and evaluation of their potential antimicrobial activity

    International Nuclear Information System (INIS)

    Dar, P.; Hina, A.; Anwar, J.

    2016-01-01

    The synthesis of silver nanoparticles of three different biogenic materials Multani mitti (Fullers earth), Tomato (Solanum lycopersicum) seeds, Rice Husk (Oryza sativa) was carried out. The possible presence and variability of comprehensive biomolecules in these materials turned as capping and reducing agents which optimize the reduction rate and stabilization of silver nanoparticles. Characterizations were determined by using ultraviolet-visible (UV-Vis) spectroscopy, Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Stable silver nanoparticles of average size 4.6, 41.1 and 10.6 nm were obtained for Multani mitti, tomato seeds and rice husk respectively. Phenolic and carboxylic biomolecules were identified as active reducing agents of Ag+2 to Ag0. The antimicrobial activity was carried out against Klebsiella pneumonia, Salmonella enterica, Escherichia coli and Staphylococcus aureus strains by using well diffusion method. Maximum zone of inhibition (ZOI) was found against Staphylococcus aureus by all of the three biogenic materials. (author)

  12. Chemical Modification of Oryza sativa Linnaeus Husk with Urea for Removal of Brilliant Vital Red and Murexide Dyes from Water by Adsorption in Environmentally Benign Way

    International Nuclear Information System (INIS)

    Rehman, R.; Mahmud, T.; Kanwal, F.; Aslam, M.N.; Nisar, H.

    2013-01-01

    Oryza sativa Linnaeus is an important food item all around the world. Due to its huge consumption, a large amount of rice husk is generated as agrowaste which can be used for water treatment by adsorption. Its adsorption capacity further can be enhanced by chemical medication. In the present study, urea modified rice husk has been used for removing Brilliant Vital Red and Murexide form water in an efficient way. After optimizing operating conditions, isothermal and thermodynamical studies were carried out, which showed that maximum adsorption capacity of urea modified rice husk for removing Brilliant Vital Red and Murexide dyes were 28.93 and 30.74 mg.g/sup -1/. Adsorbent characterization was carried out by recording its FT-IR spectra. (author)

  13. In-silico analysis of cis-acting regulatory elements of pathogenesis-related proteins of Arabidopsis thaliana and Oryza sativa.

    Science.gov (United States)

    Kaur, Amritpreet; Pati, Pratap Kumar; Pati, Aparna Maitra; Nagpal, Avinash Kaur

    2017-01-01

    Pathogenesis related (PR) proteins are low molecular weight family of proteins induced in plants under various biotic and abiotic stresses. They play an important role in plant-defense mechanism. PRs have wide range of functions, acting as hydrolases, peroxidases, chitinases, anti-fungal, protease inhibitors etc. In the present study, an attempt has been made to analyze promoter regions of PR1, PR2, PR5, PR9, PR10 and PR12 of Arabidopsis thaliana and Oryza sativa. Analysis of cis-element distribution revealed the functional multiplicity of PRs and provides insight into the gene regulation. CpG islands are observed only in rice PRs, which indicates that monocot genome contains more GC rich motifs than dicots. Tandem repeats were also observed in 5' UTR of PR genes. Thus, the present study provides an understanding of regulation of PR genes and their versatile roles in plants.

  14. Influence of Rapeseed Cake on Iron Plaque Formation and Cd Uptake by Rice (Oryza sativa L.) Seedlings Exposed to Excess Cd.

    Science.gov (United States)

    Yang, Wen-Tao; Zhou, Hang; Gu, Jiao-Feng; Zeng, Qing-Ru; Liao, Bo-Han

    2017-11-01

    A soil spiking experiment at two Cd levels (0.72 and 5.20 mg kg -1 ) was conducted to investigate the effects of rapeseed cake (RSC) at application rates of 0%, 0.75%, 1.5%, and 3.0% (w/w) on iron plaque formation and Cd uptake by rice (Oryza sativa L.) seedlings. The use of RSC did result in a sharp decrease in soil bioavailability of Cd and a significant increase in rice growth, soil pH and organic matter. Application of RSC increased the amount of iron plaque formation and this effectively inhibited the uptake and translocation of Cd into the rice seedlings. RSC was an effective organic additive for increasing rice growth and reducing Cd uptake by rice plant, simultaneously. These results could be used as a reference for the safety use of Cd polluted paddy soil.

  15. Minerales, Ácido Fítico y γ-Oryzanol en harinas integrales y salvados de tres variedades de arroz (Oryza Sativa L) cultivadas en Venezuela

    OpenAIRE

    Aguilar-García, Carlos; Hevia, Patricio; Núnez, Máryuri

    2014-01-01

    El propósito de esta investigación fue determinar el contenido de algunos minerales, de ácido fítico y de γ-oryzanol en harinas integrales y salvados de tres cultivares (Cimarrón, Fonaiap 1 y Zeta 15) de arroz (Oryza sativa L) cosechados en Venezuela. Los minerales (Ca, Mg, Fe y Zn) fueron cuantificados por espectrofotometría de absorción atómica, mientras que el fósforo (P) y el ácido fítico fueron estimados a través de un método colorimétrico. El γ-oryzanol se cuantificó por HPLC. En genera...

  16. OPTIMASI SUHU REAKSI TRANSESTERIFIKASI PADA MINYAK JERAMI PADI (ORYZA SATIVA L. MENJADI BIODIESEL DENGAN MENGGUNAKAN KATALIS CAO DARI KULIT TELUR AYAM

    Directory of Open Access Journals (Sweden)

    Tasik Sinta

    2016-11-01

    Full Text Available The research on optimization of transesterification temperature for production of biodiesel from rice straw oil (Oryza sativa L. using CaO catalyst derived from the chicken egg skin has been conducted. Production of biodiesel was conducted at varied temperatures, namely 30oC, 40oC, 50oC, 60oC and 70oC. The fatty acid compositions of the transesterification products were determined by using GC-MS and the physical and chemical characteristics were determined using SNI Methods 04-7182-2006. The AAS result suggested that the chicken egg skin contained 91.41% CaO. The optimum transesterification temperature was 60oC producing 90,8405% methyl ester. The results of GC-MS showed that the highest percentage of fatty acid was methyl oleic (44.56%.

  17. Agronomic and molecular evaluation of induced mutant rice (oryza sativa l.) lines in Egypt

    International Nuclear Information System (INIS)

    Sshehzad, T.; Allah, A.; Aallah, E.A.; Ammar, M.H.; Abdelkhalik, A.H.

    2011-01-01

    The present study was conducted at the farm of the Rice Research and Training Center, Sakha, Kafr El-Sheikh, Egypt, during 2000-2007 rice sowing seasons. Five rice varieties viz., Giza 171, Giza 175, Giza 176, Giza 181 and GZ 1368 were the most widely grown Japonica and Indica types in Egypt during the last period, possesses at that time many positive agronomic characteristics including wide adaptability, high yield potential, tolerance to stresses and good eating quality. But with the passage of time it has lost its vigor. In Rice Research Program, Egypt, dry seeds of the above mentioned varieties were treated with different doses of gamma rays (100, 200, 300, 400, and 500 Gy) for raising M1 generation. M1 plants were established by transplanting in the year 2000 season. One hundred independent lines have been advanced to M5 generation enabling evaluation of quantitative traits by replicated trials and promising lines were selected and tested in multi-location trials as M6, M7 and M8 generations. Morphological variations at vegetative and reproductive stages including plant type and various physiological characters were observed in the five populations. The mutant lines characteristics consisted of better resistance to lodging, blast disease, high yield potential, as well as early maturity. Results from yield trials and molecular assessments indicated that the mutants differed genetically from their parents. So, these mutants could be used as a donor parents in rice breeding program and some of them can be recommended as new rice varieties suitable for rice belt in Egypt. (author)

  18. MORPHO-MOLECULAR SCREENING OF RICE (ORYZA SATIVA L. GENOTYPES AT SEEDLING STAGE FOR SALT TOLERANCE

    Directory of Open Access Journals (Sweden)

    Ali Julfiker Md. Masud

    2014-10-01

    Full Text Available Providing adequate food to meet an escalating population is one of the gravest problems the humankind is now facing. To resolve this crisis identification of salt tolerant rice variety is very vital. So, in this research, ten rice genotypes were used to screen salinity tolerance at the seedling stage in hydroponic system using SSR markers. Salinity screening was done at glasshouse following IRRI standard protocol using two setups of salinized and non-salinized conditions. Genotypes under controlled condition had longer root and shoot length then salt stress genotypes. Parental polymorphism survey was done with ten SSR markers viz., RM336, RM510, RM7075, RM407, RM3201b, RM10748, AP3206f, RM3412, RM585, RM11504 and all were selected to evaluate salt tolerance in rice genotypes. The number of alleles per locus ranged from 3 (AP3206f to 9 (RM336, with an average of 6.1 alleles across 10 loci obtained in the study. The polymorphic information content values ranged from of 0.54 (AP3206f to a high of 0.86 (RM336 with an average of 0.74. The pair-wise comparisons of Nei’s (1973 genetic distance (D between varieties were computed from combined data for the 10 primers, ranged from 0.30 to 0.90 with an average of 0.86, while the similarity index based analysis ranged from 0.00 to 0.70. Finally, the FL-478, FL-378, Binadhan-8 and Binadhan-10 were selected as salt tolerant because they showed tolerance in phenotypic analysis. These phenotypically selected tolerant genotypes could be used for the selection of suitable parents and development of salt tolerant rice varieties.

  19. Progress and challenges in improving the nutritional quality of rice (Oryza sativa L.).

    Science.gov (United States)

    Birla, Deep Shikha; Malik, Kapil; Sainger, Manish; Chaudhary, Darshna; Jaiwal, Ranjana; Jaiwal, Pawan K

    2017-07-24

    Rice is a staple food for more than 3 billion people in more than 100 countries of the world but ironically it is deficient in many bioavailable vitamins, minerals, essential amino- and fatty-acids and phytochemicals that prevent chronic diseases like type 2 diabetes, heart disease, cancers, and obesity. To enhance the nutritional and other quality aspects of rice, a better understanding of the regulation of the processes involved in the synthesis, uptake, transport, and metabolism of macro-(starch, seed storage protein and lipid) and micronutrients (vitamins, minerals and phytochemicals) is required. With the publication of high quality genomic sequence of rice, significant progress has been made in identification, isolation, and characterization of novel genes and their regulation for the nutritional and quality enhancement of rice. During the last decade, numerous efforts have been made to refine the nutritional and other quality traits either by using the traditional breeding with high through put technologies such as marker assisted selection and breeding, or by adopting the transgenic approach. A significant improvement in vitamins (A, folate, and E), mineral (iron), essential amino acid (lysine), and flavonoids levels has been achieved in the edible part of rice, i.e., endosperm (biofortification) to meet the daily dietary allowance. However, studies on bioavailability and allergenicity on biofortified rice are still required. Despite the numerous efforts, the commercialization of biofortified rice has not yet been achieved. The present review summarizes the progress and challenges of genetic engineering and/or metabolic engineering technologies to improve rice grain quality, and presents the future prospects in developing nutrient dense rice to save the everincreasing population, that depends solely on rice as the staple food, from widespread nutritional deficiencies.

  20. Genome-wide comparative in silico analysis of the RNA helicase gene family in Zea mays and Glycine max: a comparison with Arabidopsis and Oryza sativa.

    Science.gov (United States)

    Xu, Ruirui; Zhang, Shizhong; Huang, Jinguang; Zheng, Chengchao

    2013-01-01

    RNA helicases are enzymes that are thought to unwind double-stranded RNA molecules in an energy-dependent fashion through the hydrolysis of NTP. RNA helicases are associated with all processes involving RNA molecules, including nuclear transcription, editing, splicing, ribosome biogenesis, RNA export, and organelle gene expression. The involvement of RNA helicase in response to stress and in plant growth and development has been reported previously. While their importance in Arabidopsis and Oryza sativa has been partially studied, the function of RNA helicase proteins is poorly understood in Zea mays and Glycine max. In this study, we identified a total of RNA helicase genes in Arabidopsis and other crop species genome by genome-wide comparative in silico analysis. We classified the RNA helicase genes into three subfamilies according to the structural features of the motif II region, such as DEAD-box, DEAH-box and DExD/H-box, and different species showed different patterns of alternative splicing. Secondly, chromosome location analysis showed that the RNA helicase protein genes were distributed across all chromosomes with different densities in the four species. Thirdly, phylogenetic tree analyses identified the relevant homologs of DEAD-box, DEAH-box and DExD/H-box RNA helicase proteins in each of the four species. Fourthly, microarray expression data showed that many of these predicted RNA helicase genes were expressed in different developmental stages and different tissues under normal growth conditions. Finally, real-time quantitative PCR analysis showed that the expression levels of 10 genes in Arabidopsis and 13 genes in Zea mays were in close agreement with the microarray expression data. To our knowledge, this is the first report of a comparative genome-wide analysis of the RNA helicase gene family in Arabidopsis, Oryza sativa, Zea mays and Glycine max. This study provides valuable information for understanding the classification and putative functions of

  1. Selection of rice mutants Oryza Sativa L. with tolerance to saline grounds

    International Nuclear Information System (INIS)

    Hernandez Aguero, L.A.

    2001-01-01

    A selection of rice mutants with tolerance to salinity, took place in the Escuela de Ciencias Agrarias de la Universidad Nacional de Heredia, in conditions of hothouse starting from a population of M2 segregative seed, coming from commercial seed radiated with Co 60 gamma rays. The studied segregatives were: Setesa-9, Experimental II and Experimental I. For making this selection, the seed M2 was planted in plastic trays with saline soil with electrical conductivity values from 8 to 10 mmhos/cm. In each case, non-radiated original seed was used as control. After 22 days the seedling germinated, an evaluation was made and it was seen that any of the controls had resisted to the saline stress, and only those segregatives resistent to salinity survived. These were the next ones: 9 individuals of Setesa, 10 of the Experimental II, and 9 of Experimental I. The index of selection obtained was: 3.6, 4.0 y 3.6 respectively. In a second phase of the experiment, the seedling selected as salinity resistant, were taken to the ground were they were developed for getting the M3 mutant seed tolerant to salinity. The plants were individually harvested in the ground and each one had a specific identification. Then, weight and number data, fertile grain and ineffectives of the M3 seed were taken. After, for corroborating the capacity of tolerance to salinity, M3 seed was planted in flowerpots with saline soil with a value of electrical conductivity between 8 and 10 mmhos/cm. After data were analyzed, it was proved that some rice mutants had a profit of even 28 grams for 1000 grams as: ExpI-17, ExpI-15, ExpI-08, ExpII-22, ExpII-08, ExpII-30 and Se-9-14, Se-9-39 and Se-9-10. Therefore, the methodology utilized showed being effective and efficient for the objectives of the work [es

  2. Seed-borne endophytic Bacillus amyloliquefaciens RWL-1 produces gibberellins and regulates endogenous phytohormones of Oryza sativa.

    Science.gov (United States)

    Shahzad, Raheem; Waqas, Muhammad; Khan, Abdul Latif; Asaf, Sajjad; Khan, Muhammad Aaqil; Kang, Sang-Mo; Yun, Byung-Wook; Lee, In-Jung

    2016-09-01

    Some microorganisms are adapted to an endophytic mode, living symbiotically with plants through vertical transmission in seeds. The role of plant growth-promoting endophytes has been well studied, but those of seed-associated endophytic bacteria are less understood. The current study aimed to isolate and identify bacterial endophytes associated with rice (Oryza sativa L. 'Jin so mi') seeds, their potential to produce gibberellins (GAs), and role in improving host-plant physiology. The isolated bacterial endophyte RWL-1 was identified as Bacillus amyloliquefaciens by using 16S rRNA sequencing and phylogenetic analysis. The pure culture of B. amyloliquefaciens RWL-1, supplied with deuterated internal standards, was subjected to gas chromatography and mass spectrometric selected ion monitoring (GC-MS/SIM) for quantification of GAs. Results showed the presence of GAs in various quantities (ng/mL) viz., GA20 (17.88 ± 4.04), GA36 (5.75 ± 2.36), GA24 (5.64 ± 2.46), GA4 (1.02 ± 0.16), GA53 (0.772 ± 0.20), GA9 (0.12 ± 0.09), GA19 (0.093 ± 0.13), GA5 (0.08 ± 0.04), GA12 (0.014 ± 0.34), and GA8 (0.013 ± 0.01). Since endogenous seed GAs are essential for prolonged seed growth and subsequent plant development, we used exogenous GA3 as a positive control and water as a negative control for comparative analysis of the application of B. amyloliquefaciens RWL-1 to rice plants. The growth parameters of rice plants treated with endophytic bacterial cell application was significantly increased compared to the plants treated with exogenous GA3 and water. This was also revealed by the significant up-regulation of endogenous GA1 (17.54 ± 2.40 ng), GA4 (310 ± 5.41 ng), GA7 (192.60 ± 3.32 ng), and GA9 (19.04 ± 2.49 ng) as compared to results of the positive and negative control treatments. Rice plants inoculated with B. amyloliquefaciens RWL-1 exhibited significantly higher endogenous salicylic acid (1615.06 ± 10.81 μg), whereas

  3. Comparative physical mapping of rice BAC clones linked to resistance genes Glh,Bph-3 and xa-5 in Oryza sativa L.and O.granulata Nees et Am.ex Watt.

    Institute of Scientific and Technical Information of China (English)

    XIONG Zhiyong; TAN Guangxuan; YOU Aiqing; HE Guangyuan; SHE Chaowen; LI Lijia; SONG Yunchun

    2004-01-01

    Oryza granulata Nees et Arn. ex Watt. is one of the three wild relatives of rice, which are the most valuable for study and utilization in China. In this study, the homology and physical locations of three rice resistance genes, Glh,Bph-3 and xa-5 are comparatively analyzed between O. sativa and O. granulata by Southern blotting and fluorescence in situ hybridization (FISH). The results of Southern blotting indicate that there exist homologous sequences of the tested RFLP markers in O. granulata. By using three bacterial artificial chromosome (BAC) clones scanned by the tested RFLP as probes, FISH signals are detected on both mitotic and pachytene chromosomes in O. sativa and O. granulata.Dual-color FISH demonstrates that two of the three BAC clones (14E16 and 38J9) are located on the short arm of the same chromosome pair in O. granulata. Additionally, colinearity is shown for the two clones between O. sativa and O.granulata. Another BAC clone 44B4 is located on the end of the short arm of other chromosome pair in these two species.Although the phylogenetic relationship between O. sativa and O. granulata is the most distinct in Oryza and these two species have evidently different biological features and ecological habits, the relative lengths and arm ratios of the detected chromosomes and the relative positions of the tested clone signals on chromosomes in O. granulata are quite similar to those in O. sativa.

  4. Oryza sativa L.

    African Journals Online (AJOL)

    Jane

    2011-07-11

    Jul 11, 2011 ... Disease resistance in plants is a desirable economic trait. Many disease ... in BRGA-1(blast resistant gene analogue-1), putative retro-elements and putative retro-transposons proteins in ... with approximately 150 described in the Colombia ecotype of .... molecular basis of NBS2-Pi9 in broad-spectrum blast.

  5. Oryza sativa L.

    Indian Academy of Sciences (India)

    inheritance of quantitative characters, such as yield and its components are ... A critical analysis of genetic variability is necessary for ini- ... Journal of Genetics, Vol. 95, No. ..... Science and Technology, New Delhi for their financial assistance.

  6. Evaluation of estimated daily intake (EDI) of cadmium and lead for rice (Oryza sativa L.) in calcareous soils.

    Science.gov (United States)

    Chamannejadian, Ali; Sayyad, Gholamabbas; Moezzi, Abdolamir; Jahangiri, Alireza

    2013-04-08

    The excessive amounts of cadmium and lead in food chain can cause health problems for humans and ecosystem. Rice is an important food in human diet. Therefore this study was conducted in order to investigate cadmium and Lead concentrations in seed rice (Oryza saliva) of paddy fields in southwest of Iran. A total of 70 rice seed samples were collected from paddy fields in five regions of Khuzestan province, Southwest Iran, during harvesting time. In the samples cadmium and Lead concentrations were measured. To assess the daily intake of Cadmium and Lead by rice, daily consumption of rice was calculated. The results showed that average concentrations of Cadmium and Lead in rice seeds were 273.6 and 121.8 μg/kg, respectively. Less than 72% of rice seed samples had Cadmium concentrations above 200 μg/kg (i.e. Guide value for cadmium); and less than 3% had Lead concentrations above 150 μg/kg (i.e. Guide value for Lead). The estimated daily intakes of cadmium by the local population was calculated to 0.59 μg/day kg bw, which corresponds to 59% of the tolerable daily intakes (i.e. 1 μg/day kg bw). Eleven out of 70 samples (15.71%) exceed the tolerable daily intakes. The dietary intakes for Lead in the local population ranged from 0.22 to 0.47 μg/day kg bw. Tolerable daily intakes for Lead is 3.6 μg/day kg bw. As a whole, long term consumption of the local rice may bear high risk of heavy metal exposure to the consumer in the study region.

  7. Evaluation of Genetic Diversity and Development of a Core Collection of Wild Rice (Oryza rufipogon Griff.) Populations in China.

    Science.gov (United States)

    Liu, Wen; Shahid, Muhammad Qasim; Bai, Lin; Lu, Zhenzhen; Chen, Yuhong; Jiang, Lan; Diao, Mengyang; Liu, Xiangdong; Lu, Yonggen

    2015-01-01

    Common wild rice (Oryza rufipogon Griff.), the progenitor of Asian cultivated rice (O. sativa L.), is endangered due to habitat loss. The objectives of this research were to evaluate the genetic diversity of wild rice species in isolated populations and to develop a core collection of representative genotypes for ex situ conservation. We collected 885 wild rice accessions from eight geographically distinct regions and transplanted these accessions in a protected conservation garden over a period of almost two decades. We evaluated these accessions for 13 morphological or phenological traits and genotyped them for 36 DNA markers evenly distributed on the 12 chromosomes. The coefficient of variation of quantitative traits was 0.56 and ranged from 0.37 to 1.06. SSR markers detected 206 different alleles with an average of 6 alleles per locus. The mean polymorphism information content (PIC) was 0.64 in all populations, indicating that the marker loci have a high level of polymorphism and genetic diversity in all populations. Phylogenetic analyses based on morphological and molecular data revealed remarkable differences in the genetic diversity of common wild rice populations. The results showed that the Zengcheng, Gaozhou, and Suixi populations possess higher levels of genetic diversity, whereas the Huilai and Boluo populations have lower levels of genetic diversity than do the other populations. Based on their genetic distance, 130 accessions were selected as a core collection that retained over 90% of the alleles at the 36 marker loci. This genetically diverse core collection will be a useful resource for genomic studies of rice and for initiatives aimed at developing rice with improved agronomic traits.

  8. Genetic, physiological and modelling approaches towards tolerance to salinity and low nitrogen supply in rice (Oryza sativa L.)

    NARCIS (Netherlands)

    Manneh, B.

    2004-01-01

    Keywords:   Rice, O ryza sativa , yield potential, yield gap, salinity, nitrogen supply, agro-ecosystems, Recombinant Inbred Line, genotype × environment interaction, yield components, adaptability, molecular markers, QTL, biomass, leaf area, leaf N, dry matter

  9. Comparison of physiological and anatomical changes of C3 (Oryza sativa [L.]) and C4 (Echinochloa crusgalli [L.]) leaves in response to drought stress

    Science.gov (United States)

    Hamim, Hamim; Banon, Sri; Dorly, Dorly

    2016-01-01

    The experiment aimed to analyse the different response of C3 (Oryza sativa L.) and C4 (Echinochloa crusgalli L.) species to drought stress based on physiological and anatomical properties. Seeds of rice (Oryza sativa) and Echinochloa (Echinochloa crusgalli) were grown in 15 cm (D) pot for 6 weeks under well-watered conditions. After 6 weeks the plants were divided into two groups, (1) well-watered which were watered daily, and (2) drought stress which were withheld from watering for 6 days. After 6 days of drought, the plants were then re-watered to analyse plant recovery. During drought period, the plants were analysed for growth, leaf relative water content (RWC), photosynthesis, and leaf anatomy. Drought stress significantly reduced leaf RWC of both species, but the reduction was bigger in rice than in Echinochloa. The maximum efficiency of photosynthesis (Fv/Fm) was decrease significantly in response to drought stress by about 48.04% in rice, while it was only 34.40% in Echinochloa. Anatomical analysis showed drought treatment tended to reduce leaf thickness in the area of bulliform cell, major- as well as intervein and xylem diameter, more in Echinochloa than in rice, suggesting that the decrease of vein and xylem diameter is among the anatomical parameters that is important to overcome from drought stress in Echinochloa. The number of chloroplast in the mesophyll cell and bundle sheath cell (BSC) was different between these two species, where in Echinochloa chloroplast was found in both mesophyll as well as BSC, while in rice it was only found in mesophyll cell, confirmed that Echinochloa is a C4 and rice is a C3 species. Interestingly, in Echinochloa, the number of chloroplast was significantly increased due to drought stress in BSC, but not in mesophyll cell. The number of starch granules also dramatically increased in response to drought in the mesophyll cells of rice and Echinochloa, and in the bundle sheath cell of Echinochloa which indicate that C3

  10. Identifikasi Transgene pada Tanaman Padi (oryza sativa var. koshihikari yang Ditransformasi dengan Bantuan Agrobacterium tumefaciens, Menggunakan Metode Tanpa Teknik Kultur Jaringan.

    Directory of Open Access Journals (Sweden)

    I Putu Suparthana

    2015-04-01

    Full Text Available Metode transformasi tanaman dengan bantuan Agrobacterium tumefaciens biasa dilakukan dengan melibatkan teknik kultur jaringan, akan tetapi teknik kultur jaringan memiliki beberapa kelemahan yaitu memerlukan suatu kondisi steril, memakan banyak waktu, sering terjadi mutasi dalam proses kultur in vitro dan sejumlah tanaman bersifat rekalsitran pada tahap regenerasi. Disisi lain metode baru (in planta transformation system yang dikembangkan dalam penelitian ini mampu mengatasi kelemahan-kelemahan tersebut. Penelitian dilakukan pada tanaman padi dengan bantuan A. tumefaciens sebagai inokulum namun tidak melibatkan teknik kultur jaringan pada masa regenerasinya. Biji padi (Oryza sativa L. var. Koshihikari direndam dalam air selama 2 hari, dengan demikian embrionya yang mengandung sel apikal meristem dapat diinokulasi dengan cara menusukkan jarum yang telah dicelupkan dalam inokulum. Biji padi yang telah diinokulasi selanjutnya ditumbuhkan dilapangan selayaknya pembenihan biasa tanpa perlakuan steril. Untuk menentukan keberhasilan teknik ini, dua jenis strain mutan A. tumefaciens (M-21 dan LBA4404 digunakan dalam transformasi. Mutan M-21 mengandung Tn5 tersisip dalam gen iaaM dan mutan LBA4404 membawa binari plasmid vektor. Transgen dari mutan M-21 dapat diidentifikasi dari perubahan fenotipe pada tanaman padi transgenik sedangkan dari mutan LBA4404 dapat diidentifikasi dengan uji histokimia dan ketahanan terhadap antibitik (hygromycin B.Kata kunci: in planta transformation, A. tumefaciens, transformation method

  11. Production of oleic acid ethyl ester catalyzed by crude rice bran (Oryza sativa lipase in a modified fed-batch system: problem and its solution

    Directory of Open Access Journals (Sweden)

    Indro Prastowo

    2015-01-01

    Full Text Available A fed-batch system was modified for the enzymatic production of Oleic Acid Ethyl Ester (OAEE using rice bran (Oryza sativa lipase by retaining the substrate molar ratio (ethanol/oleic acid at 2.05: 1 during the reaction. It resulted in an increase in the ester conversion up to 76.8% in the first 6 h of the reaction, and then followed by a decrease from 76.8% to 22.9% in 6 h later. Meanwhile, the production of water in the reaction system also showed a similar trend to the trend of ester production. The water was hypothesized to lead lipase to reverse the reaction which resulted in a decrease in both (water and esters in the last 6 h of the reaction. In order to overcome the problem, zeolite powders (25 and 50 mg/ml were added into the reaction system at 5 h of the reaction. As the result, final ester conversions increased drastically up to 90 - 95.7% (1.17 – 1.24 times. The addition also proved a hypothesis that the water was involved in reducing the ester conversion in the last 6 h of the reaction. Thus, the combination was effective to produce the high final ester conversion.

  12. Evaluation and characterization of advanced rice mutant line of rice (Oryza sativa), MR219-4 and MR219-9 under drought condition

    International Nuclear Information System (INIS)

    Abdul Rahim Harun; Zarith Shafika Kamarudin; Abdullah, M.Z.; Anna, L.P.K.; Sobri Hussain; Rusli Ibrahim; Khairuddin abdul Rahim

    2012-01-01

    Two advance rice mutant lines, MR219-4 and MR219-9 derived from mutagenesis of Oryza sativa cv. MR219 with gamma radiation at 300 Gy were evaluated in simulated drought condition in the greenhouse at Malaysian Nuclear Agency. The mutants were evaluated simultaneously with ARN1, a drought resistant variety and MR211 a susceptible cultivar as a check. Randomized complete block design with three replicates was used in the experiment. The evaluation and selection were done based on leaf rolling and leaf drying as well as other agronomic traits, such as, number of tillers per plant, plant height, flag leaf area, grain weight per plant, grain yield per plant, 100-grain weight, harvest index, panicle length and plant biomass. The mutants MR219-4 showed moderate tolerance and MR219-9 showed tolerance to drought respectively as compare to the check variety (ARN1, MR211) and control MR219. Leaf rolling, leaf drying, days to flowering and days to maturity are valuable secondary traits that may provide additional information for selection because of associating with the plant survival under water stress. Further research on expression of drought-tolerant lines under different drought conditions is essential in order to identify particular traits that are associated with drought tolerance and high yield potential. Similarly the importance of secondary traits, relative to other putative traits for drought tolerance, needs to be tested in various environments. (author)

  13. Isolation and Expression analysis of OsPME1, encoding for a putative Pectin Methyl Esterase from Oryza sativa (subsp. indica).

    Science.gov (United States)

    Kanneganti, Vydehi; Gupta, Aditya Kumar

    2009-04-01

    Pectin Methyl Esterases (PMEs) play an essential role during plant development by affecting the mechanical properties of the plant cell walls. Recent studies indicated that PMEs play important role in pollen tube development. In this study, we isolated a 1.3 kb cDNA clone from rice panicle cDNA library. It contained a 1038 bp of open reading frame (ORF) encoding for a putative pectin methyl esterase of 345 aminoacids with a 20 aminoacid signal peptide and was hence designated as OsPME1 (Oryza sativaPectin Methyl Esterase 1). It contained the structural arrangement GXYXE and GXXDFIF, found in the active groups of all PMEs. OsPME1 gene product shared varying identities, ranging from 52 % to 33 % with PMEs from other plant species belonging to Brassicaceae, Fabaceae, Amaranthaceae and Funariaceae. Southern blot analysis indicated that PME1 exists as a single copy in the rice genome. Expression pattern analysis revealed that OsPME1 is expressed only in pollen grains, during the later stages of their development and was also regulated by various abiotic stress treatments and phytohormones. Functional characterization of this pollen specific PME from rice would enable us to understand its role in pollen development.

  14. Impact of postharvest drying conditions on in vitro starch digestibility and estimated glycemic index of cooked non-waxy long-grain rice (Oryza sativa L.).

    Science.gov (United States)

    Donlao, Natthawuddhi; Ogawa, Yukiharu

    2017-02-01

    Wet paddy needs to be dried to reduce its moisture content after harvesting. In this study, effects of postharvest drying condition on in vitro starch digestibility and estimated glycemic index of cooked rice (Oryza sativa L.) were investigated. Varying drying conditions, i.e. hot-air drying at 40, 65, 90 and 115 °C, and sun drying were applied to raw paddy. After husking and polishing, polished grains were cooked using an electric rice cooker. Cooked samples were analyzed for their moisture content and amount of resistant and total starch. Five samples in both intact grain and slurry were digested under simulated in vitro gastrointestinal digestion process. The in vitro starch digestion rate was measured and the hydrolysis index (HI) and estimated glycemic index (eGI) were calculated. Cooked rice obtained from hot-air drying showed relatively lower HI and eGI than that obtained from sun-drying. Among samples from hot-air drying treatment, eGI of cooked rice decreased with increasing drying temperature, except for the drying temperature of 115 °C. As a result, cooked rice from the hot-air drying at 90 °C showed lowest eGI. The results indicated that cooked rice digestibility was affected by postharvest drying conditions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  15. Enhancement of gama-aminobutyric acid (GABA) and other health-related metabolites in germinated red rice (Oryza sativa L.) by ultrasonication.

    Science.gov (United States)

    Ding, Junzhou; Ulanov, Alexander V; Dong, Mengyi; Yang, Tewu; Nemzer, Boris V; Xiong, Shanbai; Zhao, Siming; Feng, Hao

    2018-01-01

    Red rice (Oryza sativa L.) that has a red (reddish brown) bran layer in de-hulled rice is known to contain rich biofunctional components. Germination is an effective technique to improve the nutritional quality, digestibility, and flavor of de-hulled rice. Ultrasonication, a form of physical stimulation, has been documented as a novel approach to improve the nutritional quality of plant-based food. This study was undertaken to test the use of ultrasound to enhance the nutritional value of red rice. Ultrasonication (5min, 16W/L) was applied to rice during soaking or after 66h germination. Changes of metabolites (amino acids, sugars, and organic acids) in red rice treated by ultrasonication were determined using a GC/MS plant primary metabolomics analysis platform. Differential expressed metabolites were identified through multivariate statistical analysis. Results showed that γ-aminobutyric acid (GABA) and riboflavin (vitamin B 2 ) in red rice significantly increased after germination for 72h, and then experienced a further increase after treatment by ultrasound at different stages during germination. The metabolomics analysis showed that some plant metabolites, i.e. GABA, O-phosphoethanolamine, and glucose-6-phosphate were significantly increased after the ultrasonic treatment (VIP>1.5) in comparison with the untreated germinated rice. The findings of this study showed that controlled germination with ultrasonic stress is an effective method to enhance GABA and other health-promoted components in de-hulled rice. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Silicon mitigates heavy metal stress by regulating P-type heavy metal ATPases, Oryza sativa low silicon genes, and endogenous phytohormones

    Science.gov (United States)

    2014-01-01

    Background Silicon (Si) application has been known to enhance the tolerance of plants against abiotic stresses. However, the protective mechanism of Si under heavy metals contamination is poorly understood. The aim of this study was to assess the role of Si in counteracting toxicity due to cadmium (Cd) and copper (Cu) in rice plants (Oryza sativa). Results Si significantly improved the growth and biomass of rice plants and reduced the toxic effects of Cd/Cu after different stress periods. Si treatment ameliorated root function and structure compared with non-treated rice plants, which suffered severe root damage. In the presence of Si, the Cd/Cu concentration was significantly lower in rice plants, and there was also a reduction in lipid peroxidation and fatty acid desaturation in plant tissues. The reduced uptake of metals in the roots modulated the signaling of phytohormones involved in responses to stress and host defense, such as abscisic acid, jasmonic acid, and salicylic acid. Furthermore, the low concentration of metals significantly down regulated the mRNA expression of enzymes encoding heavy metal transporters (OsHMA2 and OsHMA3) in Si-metal-treated rice plants. Genes responsible for Si transport (OsLSi1 and OsLSi2), showed a significant up-regulation of mRNA expression with Si treatment in rice plants. Conclusion The present study supports the active role of Si in the regulation of stresses from heavy metal exposure through changes in root morphology. PMID:24405887

  17. Comparison of gene co-networks reveals the molecular mechanisms of the rice (Oryza sativa L.) response to Rhizoctonia solani AG1 IA infection.

    Science.gov (United States)

    Zhang, Jinfeng; Zhao, Wenjuan; Fu, Rong; Fu, Chenglin; Wang, Lingxia; Liu, Huainian; Li, Shuangcheng; Deng, Qiming; Wang, Shiquan; Zhu, Jun; Liang, Yueyang; Li, Ping; Zheng, Aiping

    2018-05-05

    Rhizoctonia solani causes rice sheath blight, an important disease affecting the growth of rice (Oryza sativa L.). Attempts to control the disease have met with little success. Based on transcriptional profiling, we previously identified more than 11,947 common differentially expressed genes (TPM > 10) between the rice genotypes TeQing and Lemont. In the current study, we extended these findings by focusing on an analysis of gene co-expression in response to R. solani AG1 IA and identified gene modules within the networks through weighted gene co-expression network analysis (WGCNA). We compared the different genes assigned to each module and the biological interpretations of gene co-expression networks at early and later modules in the two rice genotypes to reveal differential responses to AG1 IA. Our results show that different changes occurred in the two rice genotypes and that the modules in the two groups contain a number of candidate genes possibly involved in pathogenesis, such as the VQ protein. Furthermore, these gene co-expression networks provide comprehensive transcriptional information regarding gene expression in rice in response to AG1 IA. The co-expression networks derived from our data offer ideas for follow-up experimentation that will help advance our understanding of the translational regulation of rice gene expression changes in response to AG1 IA.

  18. Expression, purification, crystallization and preliminary X-ray analysis of rice (Oryza sativa L.) Os4BGlu12 β-glucosidase

    International Nuclear Information System (INIS)

    Sansenya, Sompong; Ketudat Cairns, James R.; Opassiri, Rodjana

    2010-01-01

    Recombinant rice Os4BGlu12 β-glucosidase purified from E. coli was crystallized with and without 2,4-dinitrophenyl-2-deoxy-2-fluoro-β-d-glucopyranoside. Rice (Oryza sativa L.) Os4BGlu12, a glycoside hydrolase family 1 β-glucosidase (EC 3.2.1.21), was expressed as a fusion protein with an N-terminal thioredoxin/His 6 tag in Escherichia coli strain Origami B (DE3) and purified with subsequent removal of the N-terminal tag. Native Os4BGlu12 and its complex with 2,4-dinitrophenyl-2-deoxy-2-fluoro-β-d-glucopyranoside (DNP2FG) were crystallized using 19% polyethylene glycol (3350 or 2000, respectively) in 0.1 M Tris–HCl pH 8.5, 0.16 M NaCl at 288 K. Diffraction data sets for the apo and inhibitor-bound forms were collected to 2.50 and 2.45 Å resolution, respectively. The space group and the unit-cell parameters of the crystal indicated the presence of two molecules per asymmetric unit, with a solvent content of 50%. The structure of Os4BGlu12 was successfully solved in space group P4 3 2 1 2 by molecular replacement using the white clover cyanogenic β-glucosidase structure as a search model

  19. Plant growth enhancing effects by a siderophore-producing endophytic streptomycete isolated from a Thai jasmine rice plant (Oryza sativa L. cv. KDML105).

    Science.gov (United States)

    Rungin, Siriwan; Indananda, Chantra; Suttiviriya, Pavinee; Kruasuwan, Worarat; Jaemsaeng, Ratchaniwan; Thamchaipenet, Arinthip

    2012-10-01

    An endophytic Streptomyces sp. GMKU 3100 isolated from roots of a Thai jasmine rice plant (Oryza sativa L. cv. KDML105) showed the highest siderophore production on CAS agar while phosphate solubilization and IAA production were not detected. A mutant of Streptomyces sp. GMKU 3100 deficient in just one of the plant growth promoting traits, siderophore production, was generated by inactivation of a desD-like gene encoding a key enzyme controlling the final step of siderophore biosynthesis. Pot culture experiments revealed that rice and mungbean plants inoculated with the wild type gave the best enhancement of plant growth and significantly increased root and shoot biomass and lengths compared with untreated controls and siderophore-deficient mutant treatments. Application of the wild type in the presence or absence of ferric citrate significantly promoted plant growth of both plants. The siderophore-deficient mutant clearly showed the effect of this important trait involved in plant-microbe interaction in enhancement of growth in rice and mungbean plants supplied with sequestered iron. Our results highlight the value of a substantial understanding of the relationship of the plant growth promoting properties of endophytic actinomycetes to the plants. Endophytic actinomycetes, therefore, can be applied as potentially safe and environmentally friendly biofertilizers in agriculture.

  20. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Science.gov (United States)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L. D.; Anuntalabhochai, S.

    2013-07-01

    Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60-80 keV to a beam fluence range of 2 × 1016-2 × 1017 ions/cm2. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 106 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11).

  1. Competition between rice (Oryza sativa L.) and (barnyardgrass (Echinochloa crus-galli (L.) P. Beauv.) as affected by methanol foliar application.

    Science.gov (United States)

    Rezaeieh, Alireza D; Aminpanah, Hashem; Sadeghi, Seyed M

    2015-01-01

    Pot experiment was conducted in Iran, to evaluate the effect of methanol on competition between rice (Oryza sativa) and barnyardgrass (Echinochloa crus-galli). The experiment was conducted as a randomized complete block design with a factorial treatment arrangement and three replicates. Factors were two aqueous methanol foliar applications (0, and 14% v/v) and five rice: barnyardgrass ratios (100:0, 75:25, 50:50, 25:6, and 0:100). Replacement series diagrams for aboveground dry weight illustrated that 'Shiroudi' was more competitive than barnyardgrass as averaged across methanol foliar applications. When methanol was not sprayed, the lines for 'Shiroudi' and barnyardgrass intersected at 75:25 rice: barnyardgrass ratio, but when methanol was sprayed at 14% v/v, the lines for 'Shiroudi' and barnyardgrass intersect at the left of the 75:25 rice: barnyardgrass mixture proportion. These indicate that methanol application reduced competitive ability of 'Shiroudi' against barnyardgrass for aboveground biomass accumulation. At the same time, Methanol foliar application significantly reduced the relative crowding coefficient of 'Shiroudi' while simultaneously it significantly increased the relative crowding coefficient of barnyard grass. This indicates that methanol foliar application reduced the competitive ability of 'Shiroudi' against barnyardgrass for shoot biomass accumulation. This experiment illustrated that foliar spray of aqueous methanol can not be recommended for rice under weedy conditions.

  2. Effect of peanut shell and wheat straw biochar on the availability of Cd and Pb in a soil-rice (Oryza sativa L.) system.

    Science.gov (United States)

    Xu, Chao; Chen, Hao-Xiang; Xiang, Qian; Zhu, Han-Hua; Wang, Shuai; Zhu, Qi-Hong; Huang, Dao-You; Zhang, Yang-Zhu

    2018-01-01

    Soil amendments, such as biochar, have been used to enhance the immobilization of heavy metals in contaminated soil. A pot experiment was conducted to immobilize the available cadmium (Cd) and lead (Pb) in soil using peanut shell biochar (PBC) and wheat straw biochar (WBC), and to observe the accumulation of these heavy metals in rice (Oryza sativa L.). The application of PBC and WBC led to significantly higher pH, soil organic carbon (SOC), and cation exchange capacity (CEC) in paddy soil, while the content of MgCl 2 -extractable Cd and Pb was lower than that of untreated soil. MgCl 2 -extractable Cd and Pb showed significant negative correlations with pH, SOC, and CEC (p rice plants. Specially, when compared to the corresponding concentrations in rice grown in control soils, 5% PBC addition lowered Cd and Pb concentrations in grains by 22.9 and 12.2%, respectively, while WBC addition lowered them by 29.1 and 15.0%, respectively. Compared to Pb content, Cd content was reduced to a greater extent in grain by PBC and WBC. These results suggest that biochar application is effective for immobilizing Cd and Pb in contaminated paddy soil, and reduces their bioavailability in rice. Biochar could be used as a soil amendment for the remediation of soils contaminated with heavy metals.

  3. Risk Assessment of Heavy Metals Contamination in Paddy Soil, Plants, and Grains (Oryza sativa L.) at the East Coast of India

    Science.gov (United States)

    Satpathy, Deepmala; Reddy, M. Vikram; Dhal, Soumya Prakash

    2014-01-01

    Heavy metals known to be accumulated in plants adversely affect human health. This study aims to assess the effects of agrochemicals especially chemical fertilizers applied in paddy fields, which release potential toxic heavy metals into soil. Those heavy metals get accumulated in different parts of paddy plant (Oryza sativa L.) including the grains. Concentrations of nonessential toxic heavy metals (Cd, Cr, and Pb) and the micronutrients (Cu, Mn, and Zn) were measured in the paddy field soil and plant parts. Mn and Cd are found to be accumulated more in shoot than in root. The metal transfer factors from soil to rice plant were significant for Pb, Cd, Cu, Cr, Mn, and Zn. The ranking order of bioaccumulation factor (BAF) for heavy metals was Zn > Mn > Cd > Cu > Cr > Pb indicating that the accumulation of micronutrients was more than that of nonessential toxic heavy metals. The concentrations of heavy metals were found to be higher in paddy field soils than that of the nearby control soil but below permissible limits. The higher Health Index (HI) values of rice consuming adults (1.561) and children (1.360) suggest their adverse health effects in the near future. PMID:24995308

  4. Polyhydroxyalcanoates of strains of Azospirillum spp. isolated of roots of Lycopersicon esculentum Mill. “tomato” and Oryza sativa L. “rice” in Lambayeque

    Directory of Open Access Journals (Sweden)

    Katty Baca

    2010-12-01

    Full Text Available In this work was determined the concentration of polyhydroxyalkanoates (PHAs of Azospirillum strains isolated from roots of Lycopersicon esculentum Mill "tomato" and Oryza sativa L. "rice" as an alternative to accumulation of petroleum-based plastics. Previously disinfected root were plated in Nfb semisolid medium where nitrogen-fixing bacteria were recognized by a whitish film on the surface and turn from green to blue. The genus Azospirillum was identified in Congo red agar medium, obtained 96 isolates of A. lipoferum and A. brasilense on tomato and rice. Batch fermentation was performed with broth Azotobacter modified feeding a saturated solution of malic acid every 12 hours and were stained with Sudan Black B. Strains were selected with the greatest number of PHAs granules (in tomato, 18 of A. lipoferum and 2 of A. brasilense; in rice, 10 of A. lipoferum and 10 of A. brasilense and quantified the biomass and PHAs. PHAs concentration reached 0.661 gL-1 in A. lipoferum KM(T-73 and 0.738 gL-1 in A. brasilense KM(T-19, both isolated from tomato. Strains of A. lipoferum and A. brasilense isolated from tomato reached a higher concentration of biomass and PHAs against the strains of rice.

  5. 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.

  6. An assessment of Wx microsatellite allele, alkali degradation and differentiation of chloroplast DNA in traditional black rice (Oryza sativa L.) from Thailand and Lao PDR.

    Science.gov (United States)

    Prathepha, Preecha

    2007-01-15

    Thailand and Lao PDR are the country's rich rice diversity. To contribute a significant knowledge for development new rice varieties, a collection of 142 black rice (Oryza sativa) accessions were determined for variation of physico-chemical properties, Wx microsatellite allele, Wx allele and chloroplast DNA type. The results showed that amylose content of black rice accessions were ranged from 1.9 to 6.8%. All of the alkali disintegration types (high, intermediate and low) was observed in these rice with average of 1.75 on the 1-3 digestibility scale. The unique Wx microsatellite allele (CT)17 was found in these samples and all black rice strains carried Wx(b) allele. In addition, all black rice accessions were found the duplication of the 23 bp sequence motif in the exon 2 of the wx gene. This evidence is a common phenomenon in glutinous rice. Based on two growing condition for black rice, rainfed lowland and rainfed upland, chloroplast DNA type was distinct from each other. All rice strains from rainfed lowland was deletion plastotype, but all other rainfed upland strains were non-deletion types.

  7. Modulation in the activity of purified tonoplast H+-ATPase by tonoplast glycolipids prepared from cultured rice (Oryza sativa L. var. Boro) cells.

    Science.gov (United States)

    Yamaguchi, M; Kasamo, K

    2001-05-01

    Glycolipids, phospholipids, and neutral lipids were extracted from the tonoplast fraction of cultured rice cells (Oryza sativa L. var. Boro). Acyl steryl glucoside (ASG) and glucocerebroside (GlcCer) were also prepared from this fraction. We determined the effects of these tonoplast lipids on the activity of H+-ATPase which was delipidated and purified from the tonoplast fraction. Exogenously added tonoplast phospholipids stimulated the activity of purified tonoplast H+-ATPase, but tonoplast glycolipids did not. When tonoplast glycolipids or tonoplast ASG was added in the presence of tonoplast phospholipids, they decreased the phospholipid-induced activation of the tonoplast H+-ATPase; tonoplast GlcCer only caused a small decrease. Steryl glucoside (SG) did not cause any decrease in this activation. Phospholipids, ASG, and GlcCer made up 35 mol%, 20 mol% and 7 mol% of the total lipids of the tonoplast fraction of cultured rice cells, respectively, and these glycolipid levels were enough to depress the phospholipid-induced activation of the tonoplast H+-ATPASE: These results revealed that H+-ATPase activity in the tonoplast may be modulated toward activation and depression by tonoplast phospholipids and glycolipids, respectively. The acylation of SG would be responsible for the depression in the phospholipid-induced H+-ATPase activity.

  8. Flavonoid glycosides from leaves and straw of Oryza sativa and their effects of cytotoxicity on a macrophage cell line and allelopathic on weed germination

    Directory of Open Access Journals (Sweden)

    Ill-Min Chung

    2018-03-01

    Full Text Available Five new flavonoids namely, 5-hydroxy-6-isoprenyl-7,4′-dimethoxyflavonol-3-O-β-d-arabinofuranoside (1, 5,7-dihydroxy-4′-methoxyflavone-7-O-β-d-arabinopyranosyl-2′′-n-decan-1′′′-oate (2, 3-butanoyl-5,6,8-trihydroxy-7,4′-dimethoxyflavonol--5-O-β-d-glucopyranoside (3, 7, 4′-dimethoxy-5-hydroxyflavone-5-O-α-d-arabinopyranosyl-(2′′ → 1′′′-O-α-d-arabinopyranoside (4, and 5,6-dihydroxy-7, 4′-dimethoxyflavone-5-O-α-d-glucopyranoside (5, together with two known compounds, were isolated from the methanol extract of Oryza sativa leaves and straw. Their structures of new compounds were elucidated by 1D and 2D NMR spectral methods, viz: COSY, HMBC and HSQC aided by mass techniques and IR spectroscopy. The cytotoxicity of these compounds (1–7 were assessed by using (RAW 264.7 mouse macrophages cell line, and allelopathic effects of compounds (1–7 on the germination characteristics of barnyardgrass (Echinochloa oryzicola and pigweed (Chenopodium album L. were also evaluated. The compounds 1, 6 and 7 showed cytotoxicity and compounds 1–7 exhibited significant inhibitory activity on the seed germination of two weed species.

  9. Reduction of aflatoxin-beta/sub 1/ and ochratoxin-A levels in polished basmati rice (oryza sativa linn.) by different cooking methods

    International Nuclear Information System (INIS)

    Hussain, A.; Luttfullah, G.

    2009-01-01

    Rice (Oryza sativa Linn) is one of the basic diets of Pakistan. The aim of present study was to evaluate the effect of different cooking methods on the levels of aflatoxin-B/sub 1/ (AFB.) and ochratoxin-A (OTA). For this purpose the rice samples were artificially contaminated with AFB1 and ochratoxin-A (OTA) individually and simultaneously. The samples were then submitted to three different cooking methods i.e. normal cooking, cooking in an excess of water and in a microwave oven. After treatment, the both toxins were determined by thin layer chromatography (TLC) technique. The highest myco toxin reductions were observed when rice samples cooked in excess water (87.5 % for AFB1 and 86.6 % for OTA), followed by normal cooking (84.0 % for AFB, and 83.0 % for OTA) and microwave oven cooking (72.5 % for AFB1 and 82.4 % for OTA). The samples artificially contaminated with both AFB1 and OTA, the highest reductions were also observed for rice cooked in excess water (87.5 and 83.0 %) than cooked by normal cooking (82.5 and 766 %), and by microwave oven cooking (77.6 and 75.9 %). The rates of toxin reduction were relatively lower in samples artificially simultaneously contaminated with AFB1 and OTA, than the rice samples contaminated with AFB. and OTA individually. (author)

  10. Possible cleavage sites of glutelin partial degradation confirmed by immunological analysis in globulin-less mutants of rice (Oryza sativa L.).

    Science.gov (United States)

    Khan, Nadar; Yamaguchi, Satoru; Katsube-Tanaka, Tomoyuki

    2017-10-01

    Proteolytic cleavage or partial degradation of proteins is one of the important post-translational modifications for various biological processes, but it is difficult to analyze. Previously, we demonstrated that some subunits of the major rice (Oryza sativa L.) seed storage protein glutelin are partially degraded to produce newly identified polypeptides X1-X5 in mutants in which another major seed storage protein globulin is absent. In this study, the new polypeptides X3 and X4/X5 were immunologically confirmed to be derived from GluA3 and GluA1/GluA2 subunits, respectively. Additionally, the new polypeptides X1 and X2 were at least in part the α polypeptides of the GluB4 subunit partially degraded at the C-terminus. Simulated 2D-PAGE migration patterns of intact and partially degraded α polypeptides based on the calculation of their MWs and pIs enabled us to narrow or predict the possible locations of cleavage sites. The predicted cleavage sites were also verified by the comparison of 2D-PAGE patterns between seed-extracted and E. coli-expressed proteins of the intact and truncated α polypeptides. The results and methodologies demonstrated here would be useful for analyses of partial degradation of proteins and the structure-function relationships of rice seed protein bodies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Determination of Optimal Harvest Time of Chuchung Variety Green Rice(®) (Oryza sativa L.) with High Contents of GABA, γ-Oryzanol, and α-Tocopherol.

    Science.gov (United States)

    Kim, Hoon; Kim, Oui-Woung; Ha, Ae Wha; Park, Soojin

    2016-06-01

    In our previous study, an early-maturing variety of rice (Oryza sativa L.), Jinbu can have feature with unique green color, various phytochemicals as well as nutritive components by the optimal early harvesting, called Green Rice(®) (GR). The aims of the present field experiments were to evaluate the changes in the weight of 1,000 kernels, yield, and contents of proximate and bioactive compounds in Chuchung, a mid-late maturing variety, during the pre-harvest maturation of rough rice and to research the appropriate harvest time and potent bioactivity of Chuchung GR. The weights of 1,000 kernels of Chuchung GR dramatically increased until 27 days after heading (DAH). The yields of Chuchung GR declined after 27 DAH and significantly declined to 0.0% after 45 DAH. The caloric value and total mineral contents were higher in the GR than in the full ripe stage, the brown rice (BR). In the GR, the contents of bioactive compounds, such as γ-aminobutyric acid, γ-oryzanol, and α-tocopherol, were much higher (P<0.05) than those in the BR, specifically during 24~27 DAH. Therefore, bioactive Chuchung GR can be produced with a reasonable yield at 24~27 DAH and it could be useful for applications in various nutritive and functional food products.

  12. Determination of Optimal Harvest Time of Chuchung Variety Green Rice® (Oryza sativa L.) with High Contents of GABA, γ-Oryzanol, and α-Tocopherol

    Science.gov (United States)

    Kim, Hoon; Kim, Oui-Woung; Ha, Ae Wha; Park, Soojin

    2016-01-01

    In our previous study, an early-maturing variety of rice (Oryza sativa L.), Jinbu can have feature with unique green color, various phytochemicals as well as nutritive components by the optimal early harvesting, called Green Rice® (GR). The aims of the present field experiments were to evaluate the changes in the weight of 1,000 kernels, yield, and contents of proximate and bioactive compounds in Chuchung, a mid-late maturing variety, during the pre-harvest maturation of rough rice and to research the appropriate harvest time and potent bioactivity of Chuchung GR. The weights of 1,000 kernels of Chuchung GR dramatically increased until 27 days after heading (DAH). The yields of Chuchung GR declined after 27 DAH and significantly declined to 0.0% after 45 DAH. The caloric value and total mineral contents were higher in the GR than in the full ripe stage, the brown rice (BR). In the GR, the contents of bioactive compounds, such as γ-aminobutyric acid, γ-oryzanol, and α-tocopherol, were much higher (P<0.05) than those in the BR, specifically during 24~27 DAH. Therefore, bioactive Chuchung GR can be produced with a reasonable yield at 24~27 DAH and it could be useful for applications in various nutritive and functional food products. PMID:27390725

  13. Uptake of Total Petroleum Hydrocarbon (TPH) and Polycyclic Aromatic Hydrocarbons (PAHs) by Oryza sativa L. Grown in Soil Contaminated with Crude Oil.

    Science.gov (United States)

    Patowary, Rupshikha; Patowary, Kaustuvmani; Devi, Arundhuti; Kalita, Mohan Chandra; Deka, Suresh

    2017-01-01

    The purpose of this study was to determine whether total petroleum hydrocarbon (TPH) and polycyclic aromatic hydrocarbons (PAHs) present in crude oil contaminated sites are transferred to roots, shoots and finally the grains of rice crops (Oryza sativa L.) grown in those sites. Soil was artificially contaminated with crude oil at concentrations of 0, 1000, 5000, 10,000, and 15,000 mg/kg, followed by planting of rice seedlings. After harvest, TPH in plant samples were measured, and it was determined that the uptake of TPH by the plants gradually increased as the concentration of oil in soil increased. Further, from GC-MS analysis, it was observed that PAHs including naphthalene and phenanthrene bioaccumulated in rice plant parts. Vital physico-chemical properties of soil were also altered due to crude oil contamination. Our study revealed that rice plants grown in crude oil polluted sites can uptake TPH including PAHs, thus emphasising the importance of prior investigation of soil condition before cultivation of crops.

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  15. The defense-responsive genes showing enhanced and repressed expression after pathogen infection in rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    ZHOU; Bin(周斌); PENG; Kaiman(彭开蔓); CHU; Zhaohui(储昭晖); WANG; Shiping(王石平); ZHANG; Qifa(张启发)

    2002-01-01

    Despite large numbers of studies about defense response, processes involved in the resistance of plants to incompatible pathogens are still largely uncharacterized. The objective of this study was to identify genes involved in defense response by cDNA array analysis and to gain knowledge about the functions of the genes involved in defense response. Approximately 20000 rice cDNA clones were arrayed on nylon filters. RNA samples isolated from different rice lines after infection with incompatible strains or isolates of Xanthomonas oryzae pv. oryzae or Pyricularia grisea, respectively, were used to synthesize cDNA as probes for screening the cDNA arrays. A total of 100 differentially expressed unique sequences were identified from 5 pathogen-host combinations. Fifty-three sequences were detected as showing enhanced expression and 47 sequences were detected as showing repressed expression after pathogen infection. Sequence analysis revealed that most of the 100 sequences had various degrees of homology with genes in databases which encode or putatively encode transcription regulating proteins, translation regulating proteins, transport proteins, kinases, metabolic enzymes, and proteins involved in other functions. Most of the genes have not been previously reported as being involved in the disease resistance response in rice. The results from cDNA arrays, reverse transcription-polymerase chain reaction, and RNA gel blot analysis suggest that activation or repression of most of these genes might occur commonly in the defense response.

  16. Genetic diversity associated with conservation of endangered Dongxiang wild rice (Oryza rufipogon)

    Science.gov (United States)

    The wild progenitor species (Oryza rufipogon) of Asian cultivated rice (O. sativa) is located in Dongxiang county, China where it is considered the northernmost range worldwide. Nine ex situ and three in situ populations of the Dongxiang wild rice (DXWR) and four groups of modern cultivars were geno...

  17. Exploring the power of rice (O. sativa x O. rufipogon) chromosome segment substitution line libraries

    Science.gov (United States)

    Transgressive variation was reported as an increase in grain yield for several rice (Oryza sativa x O. rufipogon) advanced backcross mapping populations. The objective of this study was to develop chromosome segment substitution line (CSSL) libraries to further dissect the reported transgressive var...

  18. An integrated interspecific AFLP map of lettuce (Lactuca) based on two L. Saligna x L. sativa F2-populations

    NARCIS (Netherlands)

    Jeuken, M.; Wijk, van R.; Peleman, J.; Lindhout, P.

    2001-01-01

    AFLP markers were obtained with 12 EcoRI/ MseI primer combinations on two independent F2 populations of Lactuca sativa 2 Lactuca saligna. The polymorphism rates of the AFLP products between the two different L. saligna lines was 39°between the two different L. sativa cultivars 13 nd between the L.

  19. Zinco, chumbo e cádmio em plantas de arroz (Oryza Sativa L. cultivadas em solo após adição de resíduo siderúrgico Zinc, lead and cadmium influence in rice plants (Oryza Sativa L. cultivated in soil with addition of siderurgical residue

    Directory of Open Access Journals (Sweden)

    André Fernão Martins de Andrade

    2008-10-01

    Full Text Available Os efeitos da aplicação de resíduo siderúrgico, proveniente da concentração de zinco em lama de altos-fornos siderúrgicos, como fonte de zinco para plantas de arroz (Oryza Sativa L. BRS Curinga e a toxicidade devida ao cádmio e ao chumbo no resíduo, foram estudados em experimento de casa de vegetação. O material de solo usado foi proveniente do horizonte A e B de um Latossolo Vermelho-Amarelo e do horizonte A de um Neossolo Flúvico, coletados no município de Pinheiral, Estado do Rio de Janeiro. Foram aplicadas quatro doses de resíduo (94; 281; 844 e 2531kg ha-1. Foi determinado o teor de zinco, cádmio e chumbo na raiz e na parte aérea das plantas de arroz. As plantas crescidas no horizonte A do Neossolo Flúvico apresentaram a maior produção de matéria seca e a maior acumulação de zinco e a menor de cádmio. As plantas de arroz desenvolvidas no horizonte B do Latossolo apresentaram a menor produção de matéria seca, menor acumulação de zinco e a maior de chumbo, enquanto que as cultivadas no horizonte A do Latossolo apresentaram a mais elevada produção de matéria seca dos três substratos utilizados. O zinco e o chumbo concentraram-se, principalmente, nas raízes das plantas, e o cádmio se concentrou na parte aérea. Pelas características apresentadas nos solos estudados e pelas concentrações fitotóxicas do chumbo e do cádmio encontradas nas plantas desenvolvidas sobre o horizonte B do Latossolo, não é recomendável a utilização desse resíduo como fonte de zinco para a cultura do arroz.The effects of application of siderurgical residue, originated from the zinc concentration in siderurgical high-ovens mud, as supply of zinc for rice plants (Oryza Sativa L. and the toxicity due to cadmium and lead from the residue, were studied in a greenhouse experiment.The period of the experiment was from April of 2005 to March of 2006. The soil materials were from the A and B horizons of a Yellow - Red Oxisol, and the A

  20. A walk on the wild side: Oryza species as source for rice abiotic stress tolerance.

    Science.gov (United States)

    Menguer, Paloma Koprovski; Sperotto, Raul Antonio; Ricachenevsky, Felipe Klein

    2017-01-01

    Oryza sativa, the common cultivated rice, is one of the most important crops for human consumption, but production is increasingly threatened by abiotic stresses. Although many efforts have resulted in breeding rice cultivars that are relatively tolerant to their local environments, climate changes and population increase are expected to soon call for new, fast generation of stress tolerant rice germplasm, and current within-species rice diversity might not be enough to overcome such needs. The Oryza genus contains other 23 wild species, with only Oryza glaberrima being also domesticated. Rice domestication was performed with a narrow genetic diversity, and the other Oryza species are a virtually untapped genetic resource for rice stress tolerance improvement. Here we review the origin of domesticated Oryza sativa from wild progenitors, the ecological and genomic diversity of the Oryza genus, and the stress tolerance variation observed for wild Oryza species, including the genetic basis underlying the tolerance mechanisms found. The summary provided here is important to indicate how we should move forward to unlock the full potential of these germplasms for rice improvement.

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

    Science.gov (United States)

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

    2005-03-01

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

  2. Molecular cloning, functional expression and subcellular localization of two putative vacuolar voltage-gated chloride channels in rice (Oryza sativa L.).

    Science.gov (United States)

    Nakamura, Atsuko; Fukuda, Atsunori; Sakai, Shingo; Tanaka, Yoshiyuki

    2006-01-01

    We isolated two cDNA clones (OsCLC-1 and OsCLC-2) homologous to tobacco CLC-Nt1, which encodes a voltage-gated chloride channel, from rice (Oryza sativa L. ssp. japonica, cv. Nipponbare). The deduced amino acid sequences were highly conserved (87.9% identity with each other). Southern blot analysis of the rice genomic DNA revealed that OsCLC-1 and OsCLC-2 were single-copy genes on chromosomes 4 and 2, respectively. OsCLC-1 was expressed in most tissues, whereas OsCLC-2 was expressed only in the roots, nodes, internodes and leaf sheaths. The level of expression of OsCLC-1, but not of OsCLC-2, was increased by treatment with NaCl. Both genes could partly substitute for GEF1, which encodes the sole chloride channel in yeast, by restoring growth under ionic stress. These results indicate that both genes are chloride channel genes. The proteins from both genes were immunochemically detected in the tonoplast fraction. Tagged synthetic green fluorescent protein which was fused to OsCLC-1 or OsCLC-2 localized in the vacuolar membranes. These results indicate that the proteins may play a role in the transport of chloride ions across the vacuolar membrane. We isolated loss-of-function mutants of both genes from a panel of rice mutants produced by the insertion of a retrotransposon, Tos17, in the exon region, and found inhibition of growth at all life stages.

  3. Response of yield and yield components of rice (Oryza sativa L. cv. Tarom Hashemi in rice, duck and Azolla (Azolla sp. farming

    Directory of Open Access Journals (Sweden)

    M Gharavi Baigi

    2016-05-01

    Full Text Available In order to evaluate the yield and yield components of rice (Oryza sativa L. cv. Tarom Hashemi in integrated rice, duck and Azolla, an experiment was conducted at the Research Farm of Sari University of Agricultural Sciences and Natural Resources during 2012. Experiment was arranged in split plot based on a randomized complete block design with three replications. The number of ducks as main plots at four levels (0, 400, 800 and 1200 ducks.ha-1 and Nitrogen source as sub plots at four levels (without Azolla and nitrogen, Azolla, Azolla+nitrogen and nitrogen were the treatments. Analysis of variance showed highly significant differences for the number of ducks, Azolla+nitrogen and their interaction effects of plant height, number of tillers.plant-1, number of panicle.plant-1, number of grains.panicle-1, panicle weight, panicle dry weight and grain yield. The results revealed that the highest values of plant height (133 cm, number of tillers (38 tillers.plant-1, number of panicle (24 numbers.plant-1, number of grains (171 numbers.panicle-1, panicle weight (23 g, panicle dry weight (13 g and grain yield (4 t.ha-1 were recorded in 1200 duck pieces per hectare while treated with Azolla (500 g.m-2 and nitrogen (50 kg.ha-1. In conclusion, results of the current experiment showed that increasing of duck number from 400 to 1200 pieces.ha-1 along with Azolla and nitrogen could enhance the yield and yield components of rice (Tarom Hashemi cultivar.

  4. Development of a quantitative pachytene chromosome map and its unification with somatic chromosome and linkage maps of rice (Oryza sativa L.).

    Science.gov (United States)

    Ohmido, Nobuko; Iwata, Aiko; Kato, Seiji; Wako, Toshiyuki; Fukui, Kiichi

    2018-01-01

    A quantitative pachytene chromosome map of rice (Oryza sativa L.) was developed using imaging methods. The map depicts not only distribution patterns of chromomeres specific to pachytene chromosomes, but also the higher order information of chromosomal structures, such as heterochromatin (condensed regions), euchromatin (decondensed regions), the primary constrictions (centromeres), and the secondary constriction (nucleolar organizing regions, NOR). These features were image analyzed and quantitatively mapped onto the map by Chromosome Image Analyzing System ver. 4.0 (CHIAS IV). Correlation between H3K9me2, an epigenetic marker and formation and/or maintenance of heterochromatin, thus was, clearly visualized. Then the pachytene chromosome map was unified with the existing somatic chromosome and linkage maps by physically mapping common DNA markers among them, such as a rice A genome specific tandem repeat sequence (TrsA), 5S and 45S ribosomal RNA genes, five bacterial artificial chromosome (BAC) clones, four P1 bacteriophage artificial chromosome (PAC) clones using multicolor fluorescence in situ hybridization (FISH). Detailed comparison between the locations of the DNA probes on the pachytene chromosomes using multicolor FISH, and the linkage map enabled determination of the chromosome number and short/long arms of individual pachytene chromosomes using the chromosome number and arm assignment designated for the linkage map. As a result, the quantitative pachytene chromosome map was unified with two other major rice chromosome maps representing somatic prometaphase chromosomes and genetic linkages. In conclusion, the unification of the three rice maps serves as an indispensable basic information, not only for an in-depth comparison between genetic and chromosomal data, but also for practical breeding programs.

  5. Molecular evolution of the endosperm starch synthesis pathway genes in rice (Oryza sativa L.) and its wild ancestor, O. rufipogon L.

    Science.gov (United States)

    Yu, Guoqin; Olsen, Kenneth M; Schaal, Barbara A

    2011-01-01

    The evolution of metabolic pathways is a fundamental but poorly understood aspect of evolutionary change. One approach for understanding the complexity of pathway evolution is to examine the molecular evolution of genes that together comprise an integrated metabolic pathway. The rice endosperm starch biosynthetic pathway is one of the most thoroughly characterized metabolic pathways in plants, and starch is a trait that has evolved in response to strong selection during rice domestication. In this study, we have examined six key genes (AGPL2, AGPS2b, SSIIa, SBEIIb, GBSSI, ISA1) in the rice endosperm starch biosynthesis pathway to investigate the evolution of these genes before and after rice domestication. Genome-wide sequence tagged sites data were used as a neutral reference to overcome the problems of detecting selection in species with complex demographic histories such as rice. Five variety groups of Oryza sativa (aus, indica, tropical japonica, temperate japonica, aromatic) and its wild ancestor (O. rufipogon) were sampled. Our results showed evidence of purifying selection at AGPL2 in O. rufipogon and strong evidence of positive selection at GBSSI in temperate japonica and tropical japonica varieties and at GBSSI and SBEIIb in aromatic varieties. All the other genes showed a pattern consistent with neutral evolution in both cultivated rice and its wild ancestor. These results indicate the important role of positive selection in the evolution of starch genes during rice domestication. We discuss the role of SBEIIb and GBSSI in the evolution of starch quality during rice domestication and the power and limitation of detecting selection using genome-wide data as a neutral reference.

  6. Emerging Importance of Helicases in Plant Stress Tolerance: Characterization of Oryza sativa Repair Helicase XPB2 Promoter and Its Functional Validation in Tobacco under Multiple Stresses.

    Science.gov (United States)

    Raikwar, Shailendra; Srivastava, Vineet K; Gill, Sarvajeet S; Tuteja, Renu; Tuteja, Narendra

    2015-01-01

    Genetic material always remains at the risk of spontaneous or induced damage which challenges the normal functioning of DNA molecule, thus, DNA repair is vital to protect the organisms against genetic damage. Helicases, the unique molecular motors, are emerged as prospective molecules to engineer stress tolerance in plants and are involved in nucleic acid metabolism including DNA repair. The repair helicase, XPB is an evolutionary conserved protein present in different organisms, including plants. Availability of few efficient promoters for gene expression in plants provoked us to study the promoter of XPB for better understanding of gene regulation under stress conditions. Here, we report the in silico analysis of novel stress inducible promoter of Oryza sativa XPB2 (OsXPB2). The in vivo validation of functionality/activity of OsXPB2 promoter under abiotic and hormonal stress conditions was performed by Agrobacterium-mediated transient assay in tobacco leaves using OsXPB2::GUS chimeric construct. The present research revealed that OsXPB2 promoter contains cis-elements accounting for various abiotic stresses (salt, dehydration, or cold) and hormone (Auxin, ABA, or MeJA) induced GUS expression/activity in the promoter-reporter assay. The promoter region of OsXPB2 contains CACG, GTAACG, CACGTG, CGTCA CCGCCGCGCT cis acting-elements which are reported to be salt, dehydration, cold, MeJA, or ABA responsive, respectively. Functional analysis was done by Agrobacterium-mediated transient assay using agroinfiltration in tobacco leaves, followed by GUS staining and fluorescence quantitative analyses. The results revealed high induction of GUS activity under multiple abiotic stresses as compared to mock treated control. The present findings suggest that OsXPB2 promoter is a multi-stress inducible promoter and has potential applications in sustainable crop production under abiotic stresses by regulating desirable pattern of gene expression.

  7. Small kernel 1 encodes a pentatricopeptide repeat protein required for mitochondrial nad7 transcript editing and seed development in maize (Zea mays) and rice (Oryza sativa).

    Science.gov (United States)

    Li, Xiao-Jie; Zhang, Ya-Feng; Hou, Mingming; Sun, Feng; Shen, Yun; Xiu, Zhi-Hui; Wang, Xiaomin; Chen, Zong-Liang; Sun, Samuel S M; Small, Ian; Tan, Bao-Cai

    2014-09-01

    RNA editing modifies cytidines (C) to uridines (U) at specific sites in the transcripts of mitochondria and plastids, altering the amino acid specified by the DNA sequence. Here we report the identification of a critical editing factor of mitochondrial nad7 transcript via molecular characterization of a small kernel 1 (smk1) mutant in Zea mays (maize). Mutations in Smk1 arrest both the embryo and endosperm development. Cloning of Smk1 indicates that it encodes an E-subclass pentatricopeptide repeat (PPR) protein that is targeted to mitochondria. Loss of SMK1 function abolishes the C → U editing at the nad7-836 site, leading to the retention of a proline codon that is edited to encode leucine in the wild type. The smk1 mutant showed dramatically reduced complex-I assembly and NADH dehydrogenase activity, and abnormal biogenesis of the mitochondria. Analysis of the ortholog in Oryza sativa (rice) reveals that rice SMK1 has a conserved function in C → U editing of the mitochondrial nad7-836 site. T-DNA knock-out mutants showed abnormal embryo and endosperm development, resulting in embryo or seedling lethality. The leucine at NAD7-279 is highly conserved from bacteria to flowering plants, and analysis of genome sequences from many plants revealed a molecular coevolution between the requirement for C → U editing at this site and the existence of an SMK1 homolog. These results demonstrate that Smk1 encodes a PPR-E protein that is required for nad7-836 editing, and this editing is critical to NAD7 function in complex-I assembly in mitochondria, and hence to embryo and endosperm development in maize and rice. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  8. Bio-protective microbial agents from rhizosphere eco-systems trigger plant defense responses provide protection against sheath blight disease in rice (Oryza sativa L.).

    Science.gov (United States)

    Singh, Udai B; Malviya, Deepti; Wasiullah; Singh, Shailendra; Pradhan, Jatindra K; Singh, Bhanu P; Roy, Manish; Imram, Mohd; Pathak, Neelam; Baisyal, B M; Rai, Jai P; Sarma, B K; Singh, Rajiv K; Sharma, P K; Kaur, Saman Deep; Manna, M C; Sharma, Sushil K; Sharma, Arun K

    2016-11-01

    Sheath blight of rice (Oryza sativa L.) caused by Rhizoctonia solani is a major disease and attempts are being made to develop microbe based technologies for biocontrol of this pathogen. However, the mechanisms of biocontrol are not fully understood and still require indepth study in the backdrop of emerging concepts in biological systems. The present investigation was aimed at deciphering the mechanisms of biocontrol of sheath blight of rice employing Pseudomonas fluorescens and Trichoderma harzianum as model agents for biocontrol. Initially 25, 5 and 5 strains of P. fluorescens, T. viride and T. harzianum, respectively, were screened for their biocontrol potential. Out of which, six strains with higher value of percent inhibition of fungal mycelium in dual plate assay were selected. The role of P. fluorescens, T. viride and T. harzianum were investigated in induction and bioaccumulation of natural antioxidants, defence-related biomolecules and other changes in plant which lead not only to growth promotion but also protection from pathogenic stress conditions in rice. The two most promising strains, P. fluorescens PF-08 and T. harzianum UBSTH-501 selected on the basis of in planta evaluation, when applied individually or in combination, significantly enhanced the accumulation of defence-related biomolecules, enzymes and exhibited biocontrol potential against R. solani. A modified/newly developed delivery system was applied for the first time in the experiments involving inoculation of plants with both bioagents, viz. P. fluorescens PF-08 and T. harzianum UBSTH-501. Results suggested that application of P. fluorescens PF-08 and T. harzianum UBSTH-501 alone or in combination, not only helps in control of the disease but also increases plant growth along with reduction in application of toxic chemical pesticides. Copyright © 2016 Elsevier GmbH. All rights reserved.

  9. Silicon treatment to rice (oryza sativa l. cv 'gopumbyeo') plants during different growth periods and its effects on growth and grain yield

    International Nuclear Information System (INIS)

    Kim, Y.H.; Waqas, M.; Kamran, M.

    2012-01-01

    Silicon (Si) has been considered a beneficial element for plant growth. We have assessed the effects of Si application on rice (Oryza sativa L.) growth and its grain yield at field level. For this, we performed two experiments. In experiment 1, we applied Si of three different concentrations (liquid Si-10, 25 and 36%) to the seedbed of rice before transplantation into paddy field. The results of this experiment showed that Si application to rice seedbeds did not affected the rice plant height and shoot fresh weight but its application significantly increased the pushing resistance of rice plants from 12.2-16.7% as compared with water applied control plants. The lodging index of Si treated rice plants significantly decreased (13.7% on LS-25) as compared with control. Similarly, Si treated plants had significantly higher yield. Upon Si treatment (LS-36), the grain yield per 10 acre and panicles per plant were 15.1% and 6. 3% higher than the water treated control plants respectively. The best concentration (LS-36%) revealed in the first experiment was foliar applied at 10 days before heading stage, initial tilling stage and panicle initiation stage to the rice leaves and we observed that shoot biomass was not significantly different between control and Si treated plants. However, significantly higher pushing resistance (10.5%-13.8%) and plant height (12.2%-16.7%) were observed while lower lodging index (7.6-7.8%) was recorded for Si treated plants as compared to control plants. Similarly, Si application increased the number of panicles per plant as well as the grain yield per 10 acre as compared to control. In conclusion, the Si application can significantly regulate plant growth and yield if applied at proper time with feasible concentration. (author)

  10. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    International Nuclear Information System (INIS)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L.D.; Anuntalabhochai, S.

    2013-01-01

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10 16 –2 × 10 17 ions/cm 2 . The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10 6 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  11. Enhanced UV-B radiation has little effect on growth, delta13C values and pigments of pot-grown rice (Oryza sativa) in the field

    International Nuclear Information System (INIS)

    Kim, H.Y.; Kobayashi, K.; Nouchi, I.; Yoneyama, T.

    1996-01-01

    Predicted increase in ultraviolet-B (UV-B: 280–320 mn) radiation may have adverse impacts on growth and yield of rice (Oryza sativa L.), as has been found in studies hitherto. However, most of the studies were conducted in growth chambers or greenhouses where the plants are generally more sensitive to UV-B than in the field, presumably because of the distorted balance between UV-B and ultraviolet-A as well as PAR. This study was conducted to address the effects of enhanced UV-B on growth and yield of rice under a realistic spectral balance in the field. Three cultivars, “Koshihikari”,‘IR 45’and‘IR 74’were pot-grown and irradiated with enhanced UV-B for most of the growing season in the field at Tsukuba, Japan (36°01′N, 140°07′E). The UV-B enhancement simulated ca 38% depletion of stratospheric ozone at Tsukuba. The results showed no UV-B effects on plant height, numbers of tillers and panicles, dry weight of the plant parts or the grain yield for any of the 3 cultivars. Natural abundance of 13 C in the flag leaves was not altered by the UV-B enhancement either. While UV-absorbing compounds showed no response to the UV-B enhancement, chlorophyll contents decreased with enhanced UV-B. However, the decrease of chlorophyll was limited to an early growth stage with no effect later. We thus found no extraordinary impact of the nearly doubled UV-B radiation on rice in the field, and it would appear that a reliable prediction of the effects of UV-B will require experiments carried out over a number of years under various climatic and solar UV-B regimes. (author)

  12. 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.

  13. A model explaining genotypic and ontogenetic variation of leaf photosynthetic rate in rice (Oryza sativa) based on leaf nitrogen content and stomatal conductance.

    Science.gov (United States)

    Ohsumi, Akihiro; Hamasaki, Akihiro; Nakagawa, Hiroshi; Yoshida, Hiroe; Shiraiwa, Tatsuhiko; Horie, Takeshi

    2007-02-01

    Identification of physiological traits associated with leaf photosynthetic rate (Pn) is important for improving potential productivity of rice (Oryza sativa). The objectives of this study were to develop a model which can explain genotypic variation and ontogenetic change of Pn in rice under optimal conditions as a function of leaf nitrogen content per unit area (N) and stomatal conductance (g(s)), and to quantify the effects of interaction between N and g(s) on the variation of Pn. Pn, N and g(s) were measured at different developmental stages for the topmost fully expanded leaves in ten rice genotypes with diverse backgrounds grown in pots (2002) and in the field (2001 and 2002). A model of Pn that accounts for carboxylation and CO diffusion processes, and assumes that the ratio of internal conductance to g(s) is constant, was constructed, and its goodness of fit was examined. Considerable genotypic differences in Pn were evident for rice throughout development in both the pot and field experiments. The genotypic variation of Pn was correlated with that of g(s) at a given stage, and the change of Pn with plant development was closely related to the change of N. The variation of g(s) among genotypes was independent of that of N. The model explained well the variation in Pn of the ten genotypes grown under different conditions at different developmental stages. Conclusions The response of Pn to increased N differs with g(s), and the increase in Pn of genotypes with low g(s) is smaller than that of genotypes with high g(s). Therefore, simultaneous improvements of these two traits are essential for an effective breeding of rice genotypes with increased Pn.

  14. Black rice (Oryza sativa L.) extract modulates ultraviolet-induced expression of matrix metalloproteinases and procollagen in a skin cell model.

    Science.gov (United States)

    Han, Mira; Bae, Jung-Soo; Ban, Jae-Jun; Shin, Hee Soon; Lee, Dong Hun; Chung, Jin Ho

    2018-05-01

    Exposure of the skin to ultraviolet (UV) radiation causes extracellular matrix (ECM) collapse in the dermis, owing to an increase in matrix metalloproteinase (MMP) production in both the epidermis and dermis, and a decrease in type I collagen expression in the dermis. Recently, black rice (Oryza sativa L.) was reported to have a wide range of pharmacological effects in various settings. However, the effects of black rice extract (BRE) on UV‑irradiated skin cells have not yet been characterized. BRE treatment did not affect cell morphology and viability of HaCaT and human dermal fibroblasts (HDF). We demonstrated that BRE downregulated basal and UV‑induced MMP‑1 expression in HaCaT cells. Furthermore, BRE significantly increased type I procollagen expression, and decreased MMP‑1 and MMP‑3 expression in UV‑irradiated HDF. The underlying mechanisms of these results involve a decrease in p38 and c‑Jun N‑terminal kinase activity, and suppression of UV‑induced activation of activator protein‑1 (AP‑1). BRE reduced UV‑induced reactive oxygen species production in HaCaT cells in a dose‑dependent manner. Indeed, mass spectrometry revealed that BRE contained antioxidative flavonoid components such as cyanidin‑3‑O‑β‑D‑glycoside and taxifolin‑7‑O‑glucoside. These findings suggest that BRE attenuates UV‑induced ECM damage by modulating mitogen‑activated protein kinase and AP‑1 signaling, and could be used as an active ingredient for preventing photoaging of the skin.

  15. Polihidroxialcanoatos de cepas de Azospirillum spp. aisladas de raíces de Lycopersicon esculentum Mill. “tomate” y Oryza sativa L. “arroz” en Lambayeque

    Directory of Open Access Journals (Sweden)

    Katty Baca

    2010-01-01

    Full Text Available En este trabajo se determinó la concentración de polihidroxialcanoatos (PH As de cepas de Azospirillum aisladas de raíces de Lycopersicon esculentum Mill. “tomate” y Oryza sativa L. “arroz”, como una alternativa ante la acumulación de plásticos derivados del petróleo. R aíces previamente desinfectadas se sembraron en medio Nfb se misólido, donde las bacterias fijadoras de nitrógeno se reconocieron por una película blanquecina bajo la superficie y el viraje del indicador al azul. El género Azospirillum se identificó en medio rojo de Congo, obteniéndose 96 cepas de A. lipoferum y A. brasilense en tomate y arroz. Se realizó una fermentación discontinua con caldo Azotobacter modificado, alimentando con una solución saturada de ácido málico cada 12 horas y se realizaron tinciones con Sudán Negro B. Se seleccionaron las cepas con mayor nú mero de gránulos de PHAs (en tomate , 18 de A. lipoferum y 2 de A. brasilense y en arroz, 10 de A. lipoferum y 10 de A. brasilense y se cuantificó la biomasa y PHAs. La concentración de PHAs alcanzó 0 . 661 gL - 1 en A. lipoferum KM(T - 73 y 0 . 738 gL - 1 en A. br asilense KM(T - 19. Las cepas de A. lipoferum y A. brasilense aisladas de tomate alcanzaron una mayor concentración de biomasa y PHAs frente a las cepas aisladas de arroz.

  16. Ability of Rf5 and Rf6 to Restore Fertility of Chinsurah Boro II-type Cytoplasmic Male Sterile Oryza Sativa (ssp. Japonica) Lines.

    Science.gov (United States)

    Zhang, Honggen; Che, Jianlan; Ge, Yongshen; Pei, Yan; Zhang, Lijia; Liu, Qiaoquan; Gu, Minghong; Tang, Shuzhu

    2017-12-01

    Three-line Oryza sativa (ssp. japonica) hybrids have been developed mainly using Chinsurah Boro II (BT)-type cytoplasmic male sterility (CMS). The Rf1 gene restores the fertility of BT-type CMS lines, and is the only fertility restorer gene (Rf) that has been used to produce three-line japonica hybrids. Using more Rf genes to breed BT-type restorer lines may broaden the genetic diversity of the restorer lines, and represents a viable approach to improve the heterosis level of BT-type japonica hybrids. We identified two major Rf genes from '93-11' that are involved in restoring the fertility of BT-type CMS plants. These genes were identified from resequenced chromosome segment substitution lines derived from a cross between the japonica variety 'Nipponbare' and the indica variety '93-11'. Molecular mapping results revealed that these genes were Rf5 and Rf6, which are the Rf genes that restore fertility to Honglian-type CMS lines. The BT-type F 1 hybrids with either Rf5 or Rf6 exhibited normal seed setting rates, but F 1 plants carrying Rf6 showed more stable seed setting rates than those of plants carrying Rf5 under heat-stress conditions. Furthermore, the seed setting rates of F 1 hybrids carrying both Rf5 and Rf6 were more stable than that of F 1 plants carrying only one Rf gene. Rf6 is an important genetic resource for the breeding of BT-type japonica restorer lines. Our findings may be useful for breeders interested in developing BT-type japonica hybrids.

  17. Potential Application of the Oryza sativa Monodehydroascorbate Reductase Gene (OsMDHAR to Improve the Stress Tolerance and Fermentative Capacity of Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Il-Sup Kim

    Full Text Available Monodehydroascorbate reductase (MDHAR; EC 1.6.5.4 is an important enzyme for ascorbate recycling. To examine whether heterologous expression of MDHAR from Oryza sativa (OsMDHAR can prevent the deleterious effects of unfavorable growth conditions, we constructed a transgenic yeast strain harboring a recombinant plasmid carrying OsMDHAR (p426GPD::OsMDHAR. OsMDHAR-expressing yeast cells displayed enhanced tolerance to hydrogen peroxide by maintaining redox homoeostasis, proteostasis, and the ascorbate (AsA-like pool following the accumulation of antioxidant enzymes and molecules, metabolic enzymes, and molecular chaperones and their cofactors, compared to wild-type (WT cells carrying vector alone. The addition of exogenous AsA or its analogue isoascorbic acid increased the viability of WT and ara2Δ cells under oxidative stress. Furthermore, the survival of OsMDHAR-expressing cells was greater than that of WT cells when cells at mid-log growth phase were exposed to high concentrations of ethanol. High OsMDHAR expression also improved the fermentative capacity of the yeast during glucose-based batch fermentation at a standard cultivation temperature (30°C. The alcohol yield of OsMDHAR-expressing transgenic yeast during fermentation was approximately 25% (0.18 g·g-1 higher than that of WT yeast. Accordingly, OsMDHAR-expressing transgenic yeast showed prolonged survival during the environmental stresses produced during fermentation. These results suggest that heterologous OsMDHAR expression increases tolerance to reactive oxygen species-induced oxidative stress by improving cellular redox homeostasis and improves survival during fermentation, which enhances fermentative capacity.

  18. Low pH-induced changes of antioxidant enzyme and ATPase activities in the roots of rice (Oryza sativa L. seedlings.

    Directory of Open Access Journals (Sweden)

    Yi-Kai Zhang

    Full Text Available Soil acidification is the main problem in the current rice production. Here, the effects of low pH on the root growth, reactive oxygen species metabolism, plasma membrane functions, and the transcript levels of the related genes were investigated in rice seedlings (Oryza sativa L. in a hydroponic system at pH 3.5, 4.5, and 5.5. There were two hybrid rice cultivars in this trial, including Yongyou 12 (YY12, a japonica hybrid and Zhongzheyou 1 (ZZY1, an indica hybrid. Higher H+ activity markedly decreased root length, the proportion of fine roots, and dry matter production, but induced a significant accumulation of hydrogen peroxide (H2O2, and led to serious lipid peroxidation in the roots of the two varieties. The transcript levels of copper/zinc superoxide dismutase 1 (Cu/Zn SOD1, copper/zinc superoxide dismutase 2 (Cu/Zn SOD2, catalase A (CATA and catalase B (CATB genes in YY12 and ZZY1 roots were significantly down-regulated after low pH exposure for two weeks. Meanwhile, a significant decrease was observed in the expression of the P-type Ca2+-ATPases in roots at pH 3.5. The activities of antioxidant enzymes (SOD, CAT and plasma membrane (PM Ca2+-ATPase in the two varieties were dramatically inhibited by strong rhizosphere acidification. However, the expression levels of ascorbate peroxidase 1 (APX1 and PM H+-ATPase isoform 7 were up-regulated under H+ stress compared with the control. Significantly higher activities of APX and PM H+-ATPase could contribute to the adaptation of rice roots to low pH.

  19. Do Si/As ratios in growth medium affect arsenic uptake, arsenite efflux and translocation of arsenite in rice (Oryza sativa)?

    Science.gov (United States)

    Zhang, Min; Zhao, Quanli; Xue, Peiying; Zhang, Shijie; Li, Bowen; Liu, Wenju

    2017-10-01

    Silicon (Si) may decrease the uptake and accumulation of arsenic (As) in rice. However, the effects of Si/As ratios in growth medium on arsenic uptake, arsenite efflux to the external medium and translocation of arsenite in rice are currently unclear. Rice seedlings (Oryza sativa L.) were exposed to nutrient solutions with 10 μM arsenite [As(III)] or 10 μM arsenate [As(V)] to explore the influence of different silicic acid concentrations (0, 10, 100, 1000 μM) on arsenic uptake and translocation of arsenite with or without 91 μM phosphate for 24 h. Arsenic speciation was determined in nutrient solutions, roots, and shoots. In the arsenite treatments, different Si/As ratios (1:1, 10:1, 100:1) did not affect As(III) uptake by rice roots, however they did inhibit translocation of As(III) from roots to shoots significantly (P rice roots and shoots. A Si/As ratio of 100:1 reduced As(III) translocation from roots to shoots markedly without phosphate. When phosphate was supplied, As(III) translocation from roots to shoots was significantly inhibited by Si/As ratios of 10:1 and 100:1. The results indicated that in the presence of P, different silicic acid concentrations did not impact arsenite uptake and transport in rice when arsenite was supplied. However, a Si/As ratio of 100:1 inhibited As(V) uptake, as well as As(III) efflux and translocation from roots to shoots when arsenate was supplied. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Reactive oxygen species induced by heat stress during grain filling of rice (Oryza sativa L.) are involved in occurrence of grain chalkiness.

    Science.gov (United States)

    Suriyasak, Chetphilin; Harano, Keisuke; Tanamachi, Koichiro; Matsuo, Kazuhiro; Tamada, Aina; Iwaya-Inoue, Mari; Ishibashi, Yushi

    2017-09-01

    Heat stress during grain filling increases rice grain chalkiness due to increased activity of α-amylase, which hydrolyzes starch. In rice and barley seeds, reactive oxygen species (ROS) produced after imbibition induce α-amylase activity via regulation of gibberellin (GA) and abscisic acid (ABA) levels during seed germination. Here, we examined whether ROS is involved in induction of grain chalkiness by α-amylase in developing rice grains under heat stress. To elucidate the role of ROS in grain chalkiness, we grew post-anthesis rice plants (Oryza sativa L. cv. Koshihikari) under control (25°C) or heat stress (30°C) conditions with or without antioxidant (dithiothreitol) treatment. The developing grains were analyzed for expression of NADPH oxidases, GA biosynthesis genes (OsGA3ox1, OsGA20ox1), ABA catabolism genes (OsABA8'OH1, OsABA8'OH2) and an α-amylase gene (OsAmy3E), endogenous H 2 O 2 content and the grain quality. In grains exposed to heat stress, the expression of NADPH oxidase genes (especially, OsRbohB, OsRbohD, OsRbohF and OsRbohI) and the ROS content increased. Heat stress also increased the expression of OsGA3ox1, OsGA20ox1, OsABA8'OH1, OsABA8'OH2 and OsAmy3E. On the other hand, dithiothreitol treatment reduced the effects of heat stress on the expression of these genes and significantly reduced grain chalkiness induced by heat stress. These results suggest that, similar to cereal seed germination mechanism, ROS produced under heat stress is involved in α-amylase induction in maturating rice grains through GA/ABA metabolism, and consequently caused grain chalkiness. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Contamination of rice (Oryza sativa L) with Cadmium and Arsenic by irrigation with the Bogota River water in rice soils of the Lower Basin

    International Nuclear Information System (INIS)

    Montenegro, Omar; Mejia L

    2001-01-01

    In this study, field and greenhouse experiments were simultaneously carried out with rice (oryza sativa l., variedad oryzica-1) in soils of the Bogota River lower basin (Los Manueles Series, a member of the clayed, mixed, isohipertermic family of the Fluventic Vertic Haplustepts) to evaluate the effect of Cd and As content of the irrigation waters (of the Bogota River and greenhouse) on soils and: 1) rice growth physiological parameters; 2) Cd and As accumulated in different parts of rice plants; 3) yields and other aspects and properties of rice crop. The results lead to the following conclusions: 1) The Cd and As content of the Bogota River water, increased during the driest months and was minimum in those with the highest precipitation; Cd and As concentrations in both seasons surpassed the maximum permissible limits. 2) Rice height was highest when irrigation water does have neither Cd nor As. Effects of both elements showed an inverse lineal tendency. 3) The gradual increase of Cd in irrigation water reduced in 12.5% the number of grains per panicle; the increase of As induced a 10% reduction. 4) The highest concentration of Cd and As in irrigation waters significantly reduced yields; maximum yields l were obtained when Cd and As were absent from irrigation waters. 5) For any concentration of As in irrigation water the highest concentration of Cd was accumulated in rice leafs when concentration of Cd 2 was 2mg/l; above this value Cd accumulation in leafs el decreased with the gradual increase of As concentration. 6) Cd and As accumulated in rice grains increased with the gradual increment of both elements in the irrigation waters; Cd and As accumulated were respectively 50 and 15 times higher than the maximum critical levels proposed for rice grains. 7) Cd and As accumulated progressively on soils with gradual increase of both elements in irrigation waters 8) Cd and As concentration in irrigation waters apparently does not affect the rice mill behavior

  2. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Mahadtanapuk, S. [School of Agriculture and Natural Resources, University of Phayao, Phayao 56000 (Thailand); Teraarusiri, W. [Central Laboratory, University of Phayao, Phayao 56000 (Thailand); Phanchaisri, B. [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@frnf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Anuntalabhochai, S., E-mail: burinka@hotmail.com [Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2013-07-15

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10{sup 16}–2 × 10{sup 17} ions/cm{sup 2}. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10{sup 6} spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  3. In silico analysis of cis-acting regulatory elements in 5' regulatory regions of sucrose transporter gene families in rice (Oryza sativa Japonica) and Arabidopsis thaliana.

    Science.gov (United States)

    Ibraheem, Omodele; Botha, Christiaan E J; Bradley, Graeme

    2010-12-01

    The regulation of gene expression involves a multifarious regulatory system. Each gene contains a unique combination of cis-acting regulatory sequence elements in the 5' regulatory region that determines its temporal and spatial expression. Cis-acting regulatory elements are essential transcriptional gene regulatory units; they control many biological processes and stress responses. Thus a full understanding of the transcriptional gene regulation system will depend on successful functional analyses of cis-acting elements. Cis-acting regulatory elements present within the 5' regulatory region of the sucrose transporter gene families in rice (Oryza sativa Japonica cultivar-group) and Arabidopsis thaliana, were identified using a bioinformatics approach. The possible cis-acting regulatory elements were predicted by scanning 1.5kbp of 5' regulatory regions of the sucrose transporter genes translational start sites, using Plant CARE, PLACE and Genomatix Matinspector professional databases. Several cis-acting regulatory elements that are associated with plant development, plant hormonal regulation and stress response were identified, and were present in varying frequencies within the 1.5kbp of 5' regulatory region, among which are; A-box, RY, CAT, Pyrimidine-box, Sucrose-box, ABRE, ARF, ERE, GARE, Me-JA, ARE, DRE, GA-motif, GATA, GT-1, MYC, MYB, W-box, and I-box. This result reveals the probable cis-acting regulatory elements that possibly are involved in the expression and regulation of sucrose transporter gene families in rice and Arabidopsis thaliana during cellular development or environmental stress conditions. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. The Effect of Silicon on Photosynthesis and Expression of Its Relevant Genes in Rice (Oryza sativa L.) under High-Zinc Stress

    Science.gov (United States)

    Song, Alin; Li, Ping; Fan, Fenliang; Li, Zhaojun; Liang, Yongchao

    2014-01-01

    The main objectives of this study were to elucidate the roles of silicon (Si) in alleviating the effects of 2 mM zinc (high Zn) stress on photosynthesis and its related gene expression levels in leaves of rice (Oryza sativa L.) grown hydroponically with high-Zn stress. The results showed that photosynthetic parameters, including net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration, chlorophyll concentration and the chlorophyll fluorescence, were decreased in rice exposed to high-Zn treatment. The leaf chloroplast structure was disordered under high-Zn stress, including uneven swelling, disintegrated and missing thylakoid membranes, and decreased starch granule size and number, which, however, were all counteracted by the addition of 1.5 mM Si. Furthermore, the expression levels of Os08g02630 (PsbY), Os05g48630 (PsaH), Os07g37030 (PetC), Os03g57120 (PetH), Os09g26810 and Os04g38410 decreased in Si-deprived plants under high-Zn stress. Nevertheless, the addition of 1.5 mM Si increased the expression levels of these genes in plants under high-Zn stress at 72 h, and the expression levels were higher in Si-treated plants than in Si-deprived plants. Therefore, we conclude that Si alleviates the Zn-induced damage to photosynthesis in rice. The decline of photosynthesis in Zn-stressed rice was attributed to stomatal limitation, and Si activated and regulated some photosynthesis-related genes in response to high-Zn stress, consequently increasing photosynthesis. PMID:25426937

  5. A novel epistatic interaction at two loci causing hybrid male sterility in an inter-subspecific cross of rice (Oryza sativa L.).

    Science.gov (United States)

    Kubo, Takahiko; Yamagata, Yoshiyuki; Eguchi, Maki; Yoshimura, Atsushi

    2008-12-01

    Postzygotic reproductive isolation (RI) often arises in inter-subspecific crosses as well as inter-specific crosses of rice (Oryza sativa L.). To further understand the genetic architecture of the postzygotic RI, we analyzed genes causing hybrid sterility and hybrid breakdown in a rice inter-subspecific cross. Here we report hybrid male sterility caused by epistatic interaction between two novel genes, S24 and S35, which were identified on rice chromosomes 5 and 1, respectively. Genetic analysis using near-isogenic lines (NILs) carrying IR24 (ssp. indica) segments with Asominori (ssp. japonica) genetic background revealed a complicated aspect of the epistasis. Allelic interaction at the S24 locus in the heterozygous plants caused abortion of male gametes carrying the Asominori allele (S24-as) independent of the S35 genotype. On the other hand, male gametes carrying the Asominori allele at the S35 locus (S35-as) showed abortion only when the IR24 allele at the S24 locus (S24-ir) was concurrently introgressed into the S35 heterozygous plants, indicating that the sterility phenotype due to S35 was dependent on the S24 genotype through negative epistasis between S24-ir and S35-as alleles. Due to the interaction between S24 and S35, self-pollination of the double heterozygous plants produced pollen-sterile progeny carrying the S24-ir/S24-ir S35-as/S35-ir genotype in addition to the S24 heterozygous plants. This result suggests that the S35 gene might function as a modifier of S24. This study presents strong evidence for the importance of epistatic interaction as a part of the genetic architecture of hybrid sterility in rice. In addition, it suggests that diverse systems have been developed as postzygotic RI mechanisms within the rice.

  6. Morphological and Molecular Data Reveal Three Distinct Populations of Indian Wild Rice Oryza rufipogon Griff. Species Complex.

    Science.gov (United States)

    Singh, Balwant; Singh, Nisha; Mishra, Shefali; Tripathi, Kabita; Singh, Bikram P; Rai, Vandna; Singh, Ashok K; Singh, Nagendra K

    2018-01-01

    Wild relatives of crops possess adaptive mutations for agronomically important traits, which could play significant role in crop improvement for sustainable agriculture. However, global climate change and human activities pose serious threats to the natural habitats leading to erosion of genetic diversity of wild rice populations. The purpose of this study was to explore and characterize India's huge untapped wild rice diversity in Oryza rufipogon Griff. species complex from a wide range of ecological niches. We made strategic expeditions around diversity hot spots in 64 districts of nine different agro-climatic zones of the country and collected 418 wild rice accessions. Significant variation was observed among the accessions for 46 morphological descriptors, allowing classification into O. nivara, O. rufipogon , and O. sativa f. spontanea morpho-taxonomic groups. Genome-specific pSINE1 markers confirmed all the accessions having AA genome, which were further classified using ecotype-specific pSINE1 markers into annual, perennial, intermediate, and an unknown type. Principal component analysis revealed continuous variation for the morphological traits in each ecotype group. Genetic diversity analysis based on multi-allelic SSR markers clustered these accessions into three major groups and analysis of molecular variance for nine agro-climatic zones showed that 68% of the genetic variation was inherent amongst individuals while only 11% of the variation separated the zones, though there was significant correlation between genetic and spatial distances of the accessions. Model based population structure analysis using genome wide bi-allelic SNP markers revealed three sub-populations designated 'Pro-Indica,' 'Pro-Aus,' and 'Mid-Gangetic,' which showed poor correspondence with the morpho - taxonomic classification or pSINE1 ecotypes. There was Pan-India distribution of the 'Pro-Indica' and 'Pro-Aus' sub-populations across agro-climatic zones, indicating a more

  7. Morphological and Molecular Data Reveal Three Distinct Populations of Indian Wild Rice Oryza rufipogon Griff. Species Complex

    Science.gov (United States)

    Singh, Balwant; Singh, Nisha; Mishra, Shefali; Tripathi, Kabita; Singh, Bikram P.; Rai, Vandna; Singh, Ashok K.; Singh, Nagendra K.

    2018-01-01

    Wild relatives of crops possess adaptive mutations for agronomically important traits, which could play significant role in crop improvement for sustainable agriculture. However, global climate change and human activities pose serious threats to the natural habitats leading to erosion of genetic diversity of wild rice populations. The purpose of this study was to explore and characterize India’s huge untapped wild rice diversity in Oryza rufipogon Griff. species complex from a wide range of ecological niches. We made strategic expeditions around diversity hot spots in 64 districts of nine different agro-climatic zones of the country and collected 418 wild rice accessions. Significant variation was observed among the accessions for 46 morphological descriptors, allowing classification into O. nivara, O. rufipogon, and O. sativa f. spontanea morpho-taxonomic groups. Genome-specific pSINE1 markers confirmed all the accessions having AA genome, which were further classified using ecotype-specific pSINE1 markers into annual, perennial, intermediate, and an unknown type. Principal component analysis revealed continuous variation for the morphological traits in each ecotype group. Genetic diversity analysis based on multi-allelic SSR markers clustered these accessions into three major groups and analysis of molecular variance for nine agro-climatic zones showed that 68% of the genetic variation was inherent amongst individuals while only 11% of the variation separated the zones, though there was significant correlation between genetic and spatial distances of the accessions. Model based population structure analysis using genome wide bi-allelic SNP markers revealed three sub-populations designated ‘Pro-Indica,’ ‘Pro-Aus,’ and ‘Mid-Gangetic,’ which showed poor correspondence with the morpho-taxonomic classification or pSINE1 ecotypes. There was Pan-India distribution of the ‘Pro-Indica’ and ‘Pro-Aus’ sub-populations across agro-climatic zones

  8. Gene manipulation for salt tolerance and blast resistance through in vitro techniques in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Reddy, G.M.

    1990-01-01

    Full text: Rice calli generally lose regenerating ability in about 90 days. However, plant regeneration (60-70%) from 1500 day old embryo calli of 'Thellahamsa' cultivar has been established with 3% sorbitol/mannitol on LS media for efficient genetic manipulation at the cellular level. Matured embryo calli of four susceptible cultivars, 'Tellahamsa', 'Jaya', 'HR-2' and 'Zenith' were irradiated (0.1-0.5 kR) and challenged with Pyricularia oryzae spore suspensions (10 5 /ml) and with the major toxin d-picolinic acid (125-200 ppm). A total of 514 plants were regenerated from the resistant calli. The TC-2 plants exhibited varying degrees of resistance (66-78%). The genetic basis of resistance of regenerated plants and their progeny may help in understanding the mechanism. Rice embryo calli of nine scented and non-scented cultivars were challenged with NaCI (0.5-2%) and 25-50% sea water with or without proline. A total of 222 plants were regenerated. The progeny of TC-2 plants were evaluated with normal and saline soil (EC 13.5 ds/m) for yield parameters. These studies suggested that stable tolerant TC-2 plants under stress exhibited superior yield parameters and the salinity index ranged from 89.4-98.4. (author)

  9. Gene manipulation for salt tolerance and blast resistance through in vitro techniques in rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, G M [Department of Genetics, Osmania University, Hyderabad (India)

    1990-01-01

    Full text: Rice calli generally lose regenerating ability in about 90 days. However, plant regeneration (60-70%) from 1500 day old embryo calli of 'Thellahamsa' cultivar has been established with 3% sorbitol/mannitol on LS media for efficient genetic manipulation at the cellular level. Matured embryo calli of four susceptible cultivars, 'Tellahamsa', 'Jaya', 'HR-2' and 'Zenith' were irradiated (0.1-0.5 kR) and challenged with Pyricularia oryzae spore suspensions (10{sup 5}/ml) and with the major toxin d-picolinic acid (125-200 ppm). A total of 514 plants were regenerated from the resistant calli. The TC-2 plants exhibited varying degrees of resistance (66-78%). The genetic basis of resistance of regenerated plants and their progeny may help in understanding the mechanism. Rice embryo calli of nine scented and non-scented cultivars were challenged with NaCI (0.5-2%) and 25-50% sea water with or without proline. A total of 222 plants were regenerated. The progeny of TC-2 plants were evaluated with normal and saline soil (EC 13.5 ds/m) for yield parameters. These studies suggested that stable tolerant TC-2 plants under stress exhibited superior yield parameters and the salinity index ranged from 89.4-98.4. (author)

  10. Genetic interactions between diverged alleles of Early heading date 1 (Ehd1) and Heading date 3a (Hd3a)/ RICE FLOWERING LOCUS T1 (RFT1) control differential heading and contribute to regional adaptation in rice (Oryza sativa).

    Science.gov (United States)

    Zhao, Jing; Chen, Hongyi; Ren, Ding; Tang, Huiwu; Qiu, Rong; Feng, Jinglei; Long, Yunming; Niu, Baixiao; Chen, Danping; Zhong, Tianyu; Liu, Yao-Guang; Guo, Jingxin

    2015-11-01

    Initiation of flowering, also called heading, in rice (Oryza sativa) is determined by the florigens encoded by Heading date 3a (Hd3a) and RICE FLOWERING LOCUS T1 (RFT1). Early heading date 1 (Ehd1) regulates Hd3a and RFT1. However, different rice varieties have diverged alleles of Ehd1 and Hd3a/RFT1 and their genetic interactions remain largely unclear. Here we generated three segregating populations for different combinations of diverged Ehd1 and Hd3a/RFT1 alleles, and analyzed their genetic interactions between these alleles. We demonstrated that, in an ehd1 mutant background, Hd3a was silenced, but RFT1 was expressed (although at lower levels than in plants with a functional Ehd1) under short-day (SD) and long-day (LD) conditions. We identified a nonfunctional RFT1 allele (rft1); the lines carrying homozygous ehd1 and Hd3a/rft1 failed to induce the floral transition under SD and LD conditions. Like Hd3a, RFT1 also interacted with 14-3-3 proteins, the florigen receptors, but a nonfunctional RFT1 with a crucial E105K mutation failed to interact with 14-3-3 proteins. Furthermore, analyses of sequence variation and geographic distribution suggested that functional RFT1 alleles were selected during rice adaptation to high-latitude regions. Our results demonstrate the important roles of RFT1 in rice flowering and regional adaptation. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  11. Potential of Anti Breast Cancer Black Ethanol Rice Extract (Oryza sativa L. indica In Decreasing Levels of CA 15-3 Serum in the White Mice Sprague dawley in Induction 7.12-Dimethylbenz (α Antracene (DMBA and Estrogen

    Directory of Open Access Journals (Sweden)

    Zanuar Abidin

    2017-01-01

    Full Text Available Breast cancer is cancer that has the high incidence in Indonesia. Black rice (Oryza sativa L. indica is a plant that has an anticancer potency. This research aim is to prove black rice as a potential anticancer by using experimental animals, 20 Sprague Dawley female rats aged 7-8 weeks induced breast cancer by using the combination of 7,12-dimethylbenz (α anthracene (DMBA and estrogen. Rats were divided into two groups, namely the K-induced breast cancer and a group of P-induced cancer and treated with black rice. Black rice is given in the form of ethanol extract at a dose of 75 mg / kg / day for six weeks. Levels of CA 15-3 serum are used as a parameter. The result showed that the differences in levels of serum CA 15-3 are significant (p <0.05. Serum CA 15-3 level in P group is lower than in K group. This study proved that the ethanol extract of black rice (Oryza sativa L. indica has potential as an anticancer breast as indicated by decreased level of serum CA 15-3

  12. All roads lead to weediness: patterns of genomic divergence reveal extensive recurrent weedy rice origins from South Asian Oryza

    Science.gov (United States)

    Weedy rice (Oryza spp.), a weedy relative of cultivated rice (O. sativa), invades 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 b...

  13. Involvement of NADPH oxidase isoforms in the production of O2- manipulated by ABA in the senescing leaves of early-senescence-leaf (esl) mutant rice (Oryza sativa).

    Science.gov (United States)

    Li, Zhaowei; Wang, Fubiao; Zhao, Qian; Liu, Jianchao; Cheng, Fangmin

    2018-01-01

    In this study, the differences in reactive oxygen species (ROS) generation and abscisic acid (ABA) accumulation in senescing leaves were investigated by early-senescence-leaf (esl) mutant and its wild type, to clarify the relationship among ABA levels, ROS generation, and NADPH oxidase (Nox) in senescing leaves of rice (Oryza sativa). The temporal expression levels of OsNox isoforms in senescing leaves and their expression patterns in response to ABA treatment were determined through quantitative real-time reverse transcription PCR (qRT-PCR). Results showed that the flag leaf of the esl mutant generated more O2- concentrations and accumulated higher ABA levels than the wild-type cultivar did in the grain-filling stage. Exogenous ABA treatment induced O2- generation; however, it was depressed by diphenyleneiodonium chloride (DPI) pretreatment in the detached leaf segments. This finding suggested the involvement of NADPH oxidase in ABA-induced O2- generation. The esl mutant exhibited significantly higher expression of OsNox2, OsNox5, OsNox6, and OsNox7 in the initial of grain-filling stage, followed by sharply decrease. The transcriptional levels of OsNox1, OsNox3, and OsFR07 in the flag leaf of the esl mutant were significantly lower than those in the wild-type cultivar. The expression levels of OsNox2, OsNox5, OsNox6, and OsNox7 were significantly enhanced by exogenous ABA treatments. The enhanced expression levels of OsNox2 and OsNox6 were dependent on the duration of ABA treatment. The inducible expression levels of OsNox5 and OsNox7 were dependent on ABA concentrations. By contrast, exogenous ABA treatment severely repressed the transcripts of OsNox1, OsNox3, and OsFR07 in the detached leaf segments. Therefore, OsNox2, OsNox5, OsNox6, and OsNox7 were probably involved in the ABA-induced O2- generation in the initial stage of leaf senescence. Subsequently, other oxidases activated in deteriorating cells were associated with ROS generation and accumulation in the

  14. Emerging importance of helicases in plant stress tolerance: characterization of Oryza sativa repair helicase XPB2 promoter and its functional validation in tobacco under multiple stresses

    Directory of Open Access Journals (Sweden)

    Shailendra eRaikwar

    2015-12-01

    Full Text Available Genetic material always remains at the risk of spontaneous or induced damage which challenges the normal functioning of DNA molecule, thus, DNA repair is vital to protect the organisms against genetic damage. DNA hHelicases, the unique molecular motors, are emerged as potentialprospective molecules to engineer stress tolerance in plants and are involved in a variety of DNA nucleic acid metabolismc processes including DNA repair. The DNA repair helicase, OsXPB2 is an evolutionary conserved protein present in different organisms, including plants. Availability of few efficient promoters for gene expression in plants provoked us to study the promoter of XPB for better understanding of gene regulation under stress The analysis of promoter sequence from plant genome is important in understanding the gene regulation. Hereconditions. Here, we report the in silico analysis of novel stress inducible promoter of rice Oryza sativa OsXPB2 (OsXPB2. gene is reported. The in vivo validation of functionality/activity of novel stress inducible promoter of rice OsXPB2 gene promoter under abiotic and hormonal stress conditions was performed by Agrobacterium-mediated transient assay in tobacco leaves using OsXPB2::GUS chimeric construct. Our resultsThe present research revealed that OsXPB2 promoter contains cis-elements accounting for various abiotic stresses (salt, dehydration or cold and hormone (Auxin, ABA or MeJA induced GUS expression/activity in the promoter-reporter assay. The promoter region of OsXPB2 contains CACG, GTAACG, CACGTG, CGTCA CCGCCGCGCT cis acting-elements which are reported to be salt, dehydration, cold, MeJA or ABA responsive, respectively. Functional analysis was done by Agrobacterium-transient assays using agroinfiltration in tobacco leaves, followed by GUS staining and fluorescence quantitative analyses. The results revealed high induction of GUS activity under multiple abiotic stresses as compared to mock treated control. The present

  15. Allelic variants of OsHKT1;1 underlie the divergence between indica and japonica subspecies of rice (Oryza sativa for root sodium content.

    Directory of Open Access Journals (Sweden)

    Malachy T Campbell

    2017-06-01

    Full Text Available Salinity is a major factor limiting crop productivity. Rice (Oryza sativa, a staple crop for the majority of the world, is highly sensitive to salinity stress. To discover novel sources of genetic variation for salt tolerance-related traits in rice, we screened 390 diverse accessions under 14 days of moderate (9 dS·m-1 salinity. In this study, shoot growth responses to moderate levels of salinity were independent of tissue Na+ content. A significant difference in root Na+ content was observed between the major subpopulations of rice, with indica accessions displaying higher root Na+ and japonica accessions exhibiting lower root Na+ content. The genetic basis of the observed variation in phenotypes was elucidated through genome-wide association (GWA. The strongest associations were identified for root Na+:K+ ratio and root Na+ content in a region spanning ~575 Kb on chromosome 4, named Root Na+ Content 4 (RNC4. Two Na+ transporters, HKT1;1 and HKT1;4 were identified as candidates for RNC4. Reduced expression of both HKT1;1 and HKT1;4 through RNA interference indicated that HKT1;1 regulates shoot and root Na+ content, and is likely the causal gene underlying RNC4. Three non-synonymous mutations within HKT1;1 were present at higher frequency in the indica subpopulation. When expressed in Xenopus oocytes the indica-predominant isoform exhibited higher inward (negative currents and a less negative voltage threshold of inward rectifying current activation compared to the japonica-predominant isoform. The introduction of a 4.5kb fragment containing the HKT1;1 promoter and CDS from an indica variety into a japonica background, resulted in a phenotype similar to the indica subpopulation, with higher root Na+ and Na+:K+. This study provides evidence that HKT1;1 regulates root Na+ content, and underlies the divergence in root Na+ content between the two major subspecies in rice.

  16. Expression of salt-induced 2-Cys peroxiredoxin from Oryza sativa increases stress tolerance and fermentation capacity in genetically engineered yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Kim, Il-Sup; Kim, Young-Saeng; Yoon, Ho-Sung

    2013-04-01

    Peroxiredoxins (Prxs), also termed thioredoxin peroxidases (TPXs), are a family of thiol-specific antioxidant enzymes that are critically involved in cell defense and protect cells from oxidative damage. In this study, a putative chloroplastic 2-Cys thioredoxin peroxidase (OsTPX) was identified by proteome analysis from leaf tissue samples of rice (Oryza sativa) seedlings exposed to 0.1 M NaCl for 3 days. To investigate the relationship between the OsTPX gene and the stress response, OsTPX was cloned into the yeast expression vector p426GPD under the control of the glyceraldehyde-3-phosphate dehydrogenase (GPD1) promoter, and the construct was transformed into Saccharomyces cerevisiae cells. OsTPX expression was confirmed by semi-quantitative reverse transcription-polymerase chain reaction and western blot analyses. OsTPX contained two highly conserved cysteine residues (Cys114 and Cys236) and an active site region (FTFVCPT), and it is structurally very similar to human 2-Cys Prx. Heterologous OsTPX expression increased the ability of the transgenic yeast cells to adapt and recover from reactive oxygen species (ROS)-induced oxidative stresses, such as a reduction of cellular hydroperoxide levels in the presence of hydrogen peroxide and menadione, by improving redox homeostasis. OsTPX expression also conferred enhanced tolerance to tert-butylhydroperoxide, heat shock, and high ethanol concentrations. Furthermore, high OsTPX expression improved the fermentation capacity of the yeast during glucose-based batch fermentation at a high temperature (40 °C) and at the general cultivation temperature (30 °C). The alcohol yield in OsTPX-expressing transgenic yeast increased by approximately 29 % (0.14 g g(-1)) and 21 % (0.12 g g(-1)) during fermentation at 40 and 30 °C, respectively, compared to the wild-type yeast. Accordingly, OsTPX-expressing transgenic yeast showed prolonged cell survival during the environmental stresses produced during fermentation. These

  17. Cadmium accumulation characteristics of low-cadmium rice (Oryza sativa L.) line and F1 hybrids grown in cadmium-contaminated soils.

    Science.gov (United States)

    Li, Kun; Yu, Haiying; Li, Tingxuan; Chen, Guangdeng; Huang, Fu

    2017-07-01

    Cadmium (Cd) pollution has threatened severely to food safety and human health. A pot experiment and a field experiment were conducted to investigate the difference of Cd accumulation between rice (Oryza sativa L.) lines and F 1 hybrids in Cd-contaminated soils. The adverse effect on biomass of rice lines was greater than that of F 1 hybrids under Cd treatments in the pot experiment. The variations of Cd concentration among rice cultivars in different organs were smaller in stem and leaf, but larger in root and ear. Average proportion of Cd in root of F 1 hybrids was 1.39, 1.39, and 1.16 times higher than those of rice lines at the treatment of 1, 2, and 4 mg Cd kg -1 soil, respectively. Cd concentrations in ear of F 1 hybrids were significantly lower than rice lines with the reduction from 29.24 to 50.59%. Cd concentrations in brown rice of all F 1 hybrids were less than 0.2 mg kg -1 at 1 mg Cd kg -1 soil, in which Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be screened out as cadmium-safe cultivars (CSCs) for being safe even at 2 mg Cd kg -1 soil. C268A/YaHui2816 showed the lowest Cd concentration in root among F 1 hybrids, while Lu98A/YaHui2816 and 5406A/YaHui2816 showed lower capability of Cd translocation from root to shoot under Cd exposure, which eventually caused the lower Cd accumulation in brown rice. The lower level of Cd translocation contributed to reducing the accumulation of Cd in brown rice had been validated by the field experiment. Thus, Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be considered as potential CSCs to cultivate in Cd-contaminated soils (<2 mg Cd kg -1 soil).

  18. Multifunctionality and diversity of GDSL esterase/lipase gene family in rice (Oryza sativa L. japonica genome: new insights from bioinformatics analysis

    Directory of Open Access Journals (Sweden)

    Chepyshko Hanna

    2012-07-01

    Full Text Available Abstract Background GDSL esterases/lipases are a newly discovered subclass of lipolytic enzymes that are very important and attractive research subjects because of their multifunctional properties, such as broad substrate specificity and regiospecificity. Compared with the current knowledge regarding these enzymes in bacteria, our understanding of the plant GDSL enzymes is very limited, although the GDSL gene family in plant species include numerous members in many fully sequenced plant genomes. Only two genes from a large rice GDSL esterase/lipase gene family were previously characterised, and the majority of the members remain unknown. In the present study, we describe the rice OsGELP (Oryza sativa GDSL esterase/lipase protein gene family at the genomic and proteomic levels, and use this knowledge to provide insights into the multifunctionality of the rice OsGELP enzymes. Results In this study, an extensive bioinformatics analysis identified 114 genes in the rice OsGELP gene family. A complete overview of this family in rice is presented, including the chromosome locations, gene structures, phylogeny, and protein motifs. Among the OsGELPs and the plant GDSL esterase/lipase proteins of known functions, 41 motifs were found that represent the core secondary structure elements or appear specifically in different phylogenetic subclades. The specification and distribution of identified putative conserved clade-common and -specific peptide motifs, and their location on the predicted protein three dimensional structure may possibly signify their functional roles. Potentially important regions for substrate specificity are highlighted, in accordance with protein three-dimensional model and location of the phylogenetic specific conserved motifs. The differential expression of some representative genes were confirmed by quantitative real-time PCR. The phylogenetic analysis, together with protein motif architectures, and the expression profiling were

  19. Determination of supplier-to-supplier and lot-to-lot variability in glycation of recombinant human serum albumin expressed in Oryza sativa.

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    Grant E Frahm

    Full Text Available The use of different expression systems to produce the same recombinant human protein can result in expression-dependent chemical modifications (CMs leading to variability of structure, stability and immunogenicity. Of particular interest are recombinant human proteins expressed in plant-based systems, which have shown particularly high CM variability. In studies presented here, recombinant human serum albumins (rHSA produced in Oryza sativa (Asian rice (OsrHSA from a number of suppliers have been extensively characterized and compared to plasma-derived HSA (pHSA and rHSA expressed in yeast (Pichia pastoris and Saccharomyces cerevisiae. The heterogeneity of each sample was evaluated using size exclusion chromatography (SEC, reversed-phase high-performance liquid chromatography (RP-HPLC and capillary electrophoresis (CE. Modifications of the samples were identified by liquid chromatography-mass spectrometry (LC-MS. The secondary and tertiary structure of the albumin samples were assessed with far U/V circular dichroism spectropolarimetry (far U/V CD and fluorescence spectroscopy, respectively. Far U/V CD and fluorescence analyses were also used to assess thermal stability and drug binding. High molecular weight aggregates in OsrHSA samples were detected with SEC and supplier-to-supplier variability and, more critically, lot-to-lot variability in one manufactures supplied products were identified. LC-MS analysis identified a greater number of hexose-glycated arginine and lysine residues on OsrHSA compared to pHSA or rHSA expressed in yeast. This analysis also showed supplier-to-supplier and lot-to-lot variability in the degree of glycation at specific lysine and arginine residues for OsrHSA. Both the number of glycated residues and the degree of glycation correlated positively with the quantity of non-monomeric species and the chromatographic profiles of the samples. Tertiary structural changes were observed for most OsrHSA samples which

  20. 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)

  1. Induction of dominant male sterility by using 60Co γ-rays irradiation in rice oryza sativa L

    International Nuclear Information System (INIS)

    Shu Qingyao; Wu Dianxing; Xia Yingwu; Gao Mingwei

    2000-01-01

    The fertility of M 1 plants, which developed from dried rice (c.v. Zhe9248) seeds treated with γ-rays at the dosage of 300 Gy, decreased dramatically, and some of the M 1 plants showed completely male sterile. There were still fertile and sterile plants in the M 2 F 1 population of artificially emasculated high sterile Zhe9248 M 1 plants crossed to normal variety G93-89, and consequently, Zhe9248 was back crossed to the sterile plants successively as recurrent parent. In all the above back cross populations, fertile and sterile plants segregated in a 1 : 1 ratio. The M 4 BC 2 male sterile plants were crossed to various rice materials, e.g. early season indica rice (Zhefu 504, H416), middle season indica rice (Chuan-si-ran-zhan, Yu-Zhan), maintainer lines (Fu-Nan B, 351 B) and restorer lines (IR36, 20964). In all the above F 1 populations, male sterile and fertile plants again segregated in a 1 : 1 ratio. In addition, sib-crossing were made in the back crosses and hybrid crosses between male sterile and fertile plants, male sterile and fertile plants appeared in a similar fashion as in test crosses. However, no male sterile plants were recovered from fertile plants either of back crosses or test crosses. The anthers of male sterile plants appeared small and poorly developed, the pollen showed typical abortion or round abortion, the seed set in bagged panicles was very low. The experimental data showed that this male sterile rice mutant was inherited in a single-gene mode

  2. Extração, análise e distribuição dos ácidos fenólicos em genótipos pigmentados e não pigmentados de arroz (Oryza sativa L. Extraction, analysis and distribution of phenolic acids in pigmented and non-pigmented genotypes of rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Nádia Valéria Mussi de Mira

    2008-12-01

    Full Text Available Neste estudo, avaliaram-se a distribuição dos Compostos Fenólicos Totais (CFT e o perfil de ácidos fenólicos, presentes nas frações, solúvel e insolúvel de dez genótipos de arroz (Oryza sativa L. de pericarpo pigmentado e não pigmentado. Devido à sua elevada capacidade antioxidante, os compostos fenólicos vem sendo apontados como possíveis promotores da saúde. Grande parte corresponde aos ácidos fenólicos presentes no grão sob a forma solúvel (livre e conjugada e insolúvel (ligada. Na literatura há poucas informações sobre a contribuição dos compostos fenólicos ligados, cujos teores são costumeiramente subestimados. Os CFT foram quantificados pelo método de Folin-Ciocalteau, enquanto os ácidos fenólicos por RP-HPLC. Na fração solúvel dos genótipos pigmentados, os teores de CFT foram variáveis, mas, em média, 5,7 vezes maiores do que nos não pigmentados (média de 3468 e 602 µg eq. Ácido Ferúlico (AF/g arroz, respectivamente, principalmente devido à presença de antocianinas e proantocianidinas. Na fração insolúvel, os pigmentados apresentaram duas vezes mais CFT do que os não pigmentados (825 e 378 µg eq. AF/g arroz, respectivamente, provavelmente devido à retenção de antocianinas e proantocianidinas, mesmo após cinco extrações consecutivas. Dentre os ácidos fenólicos, o ácido ferúlico foi o principal componente em todos os genótipos estudados, exceto no arroz preto, no qual predominou o ácido protocatecóico.This study was conducted to evaluate the distribution of total phenolic compounds and phenolic acids in the soluble and insoluble fractions of 10 rice (Oryza sativa L. genotypes with pigmented or non-pigmented pericarp. These compounds were reported to exert beneficial effects on human health due to their high antioxidant activities. The total phenolic compounds (CFT in both fractions was determined by the Folin-Ciocalteau method and phenolic acids RP-HPLC with Diode-Array Detection

  3. Refino de óleo de farelo de arroz (Oryza sativa L. em condições brandas para preservação do γ-orizanol Refining of rice bran oil (Oryza sativa L. to preserve γ-orizanol

    Directory of Open Access Journals (Sweden)

    Luz Maria Paucar-Menacho

    2007-08-01

    Full Text Available O γ-orizanol é um antioxidante presente no óleo de farelo de arroz, mas ausente em outros óleos vegetais, ao qual têm sido atribuídos efeitos antioxidante e hipocolesterolêmico. O conteúdo de γ-orizanol no óleo de farelo de arroz bruto varia entre 1-2%, mas durante a etapa de neutralização do refino químico, este composto fica retido na borra. O presente trabalho teve por objetivo propor uma técnica alternativa de refino físico em condições brandas para o óleo de farelo de arroz com a finalidade de preservar o γ-orizanol. Utilizou-se farelo de arroz inativado e extrusado obtido a partir do processo de produção do arroz parboilizado, sendo o óleo bruto (Oryza sativa extraído pelo método de expeller. O processo de refino do óleo bruto consistiu nas etapas de degomagem ácida (com H3PO4 85%, centrifugação, clarificação, desodorização a 180 ºC e winterização. Foram realizadas análises para caracterização e comparação do óleo bruto e refinado, seguindo metodologias oficiais da AOCS. Concluiu-se que o processo de refino físico preservou 97% do γ-orizanol, o qual potencializou a estabilidade oxidativa do óleo refinado pelo método alternativo, que apresentou uma melhoria de 33% (13,3 horas a 110 ºC do período de indução da oxidação em relação ao óleo comercial.γ-orizanol is an antioxidant present in rice bran oil, but absent in other vegetable oils, which were attributed to antioxidant and hypocholesterolemic effects. The content of γ-orizanol in crude rice bran oil varies between 1-2%, but during neutralization in chemical refining this substance is transferred to soapstock. The aim of this research is to study an alternative technique of physical refining in light conditions with the purpose of preserving γ-orizanol. Inativacted and extrused rice bran obtained by the production of parboilizated rice was used to extract crude rice bran oil (Oryza sativa by the expeller method. The process of

  4. Simultaneous Improvement and Genetic Dissection of Salt Tolerance of Rice (Oryza sativa L. by Designed QTL Pyramiding

    Directory of Open Access Journals (Sweden)

    Yunlong Pang

    2017-07-01

    Full Text Available Breeding of multi-stress tolerant rice varieties with higher grain yields is the best option to enhance the rice productivity of abiotic stresses prone areas. It also poses the greatest challenge to plant breeders to breed rice varieties for such stress prone conditions. Here, we carried out a designed QTL pyramiding experiment to develop high yielding “Green Super Rice” varieties with significantly improved tolerance to salt stress and grain yield. Using the F4 population derived from a cross between two selected introgression lines, we were able to develop six mostly homozygous promising high yielding lines with significantly improved salt tolerance and grain yield under optimal and/or saline conditions in 3 years. Simultaneous mapping using the same breeding population and tunable genotyping-by-sequencing technology, we identified three QTL affecting salt injury score and leaf chlorophyll content. By analyzing 32M SNP data of the grandparents and graphical genotypes of the parents, we discovered 87 positional candidate genes for salt tolerant QTL. According to their functional annotation, we inferred the most likely candidate genes. We demonstrated that designed QTL pyramiding is a powerful strategy for simultaneous improvement and genetic dissection of complex traits in rice.

  5. Identification of a new locus conferring antixenosis to the brown planthopper in rice cultivar Swarnalata (Oryza sativa L.).

    Science.gov (United States)

    Qiu, Y F; Cheng, L; Liu, F; Li, R B

    2013-08-29

    The brown planthopper [Nilaparvata lugens (Stål); BPH] has caused severe damage to rice production. The identification of resistance genes and the development of BPH-resistant varieties are economical and effective ways to manage this pest. Using an F2 population from a cross between the Indica cultivars 93-11 and Swarnalata, we mapped the Qbph-8 locus to a 7.3-cM region on chromosome 8 in two tests, flanked by the markers RM339 and RM515. In this population, Qbph-8 explained 7.7 and 6.6% of the phenotypic variance of BPH preference in both tests. In the BPH host choice test, the average number of settled BPHs on the Qbph-8 plants was less than that on the 93-11 plants over the 24- to 120-h observation period. Furthermore, less BPH insects were observed on the BPH6+Qbph-8 plant compared with the BPH6 plant or Qbph-8 plant, indicating a stronger antixenotic effect shown in the gene pyramiding plants. Hence, this locus can be pyramided with other BPH resistance genes and applied to breed-resistant varieties, which possibly can improve the resistance level and durable resistance to the BPH.

  6. Genetic Diversity and Elite Allele Mining for Grain Traits in Rice (Oryza sativa L.) by Association Mapping.

    Science.gov (United States)

    Edzesi, Wisdom M; Dang, Xiaojing; Liang, Lijun; Liu, Erbao; Zaid, Imdad U; Hong, Delin

    2016-01-01

    Mining elite alleles for grain size and weight is of importance for the improvement of cultivated rice and selection for market demand. In this study, association mapping for grain traits was performed on a selected sample of 628 rice cultivars using 262 SSRs. Grain traits were evaluated by grain length (GL), grain width (GW), grain thickness (GT), grain length to width ratio (GL/GW), and 1000-grain weight (TGW) in 2013 and 2014. Our result showed abundant phenotypic and genetic diversities found in the studied population. In total, 2953 alleles were detected with an average of 11.3 alleles per locus. The population was divided into seven subpopulations and the levels of linkage disequilibrium (LD) ranged from 34 to 84 cM. Genome-wide association mapping detected 10 marker trait association (MTAs) loci for GL, 1MTAs locus for GW, 7 MTAs loci for GT, 3 MTAs loci for GL/GW, and 1 MTAs locus for TGW. Twenty-nine, 2, 10, 5, and 3 elite alleles were found for the GL, GW, GT, GL/GW, and TGW, respectively. Optimal cross designs were predicted for improving the target traits. The accessions containing elite alleles for grain traits mined in this study could be used for breeding rice cultivars and cloning the candidate genes.

  7. Anthocyanins from black rice (Oryza sativa) promote immune responses in leukemia through enhancing phagocytosis of macrophages in vivo.

    Science.gov (United States)

    Fan, Ming-Jen; Yeh, Ping-Hsuan; Lin, Jing-Pin; Huang, An-Cheng; Lien, Jin-Cherng; Lin, Hui-Yi; Chung, Jing-Gung

    2017-07-01

    Rice is a staple food in numerous countries around the world. Anthocyanins found in black rice have been reported to reduce the risk of certain diseases, but the effects of crude extract of anthocyanins from Asia University-selected purple glutinous indica rice (AUPGA) on immune responses have not yet been demonstrated. The current study aimed to investigate whether AUPGA treatment could affect immune responses in murine leukemia cells in vivo . Murine acute myelomonocytic leukemia WEHI-3 cells were intraperitoneally injected into normal BALB/c mice to generate leukemia mice. A total of 50 mice were randomly divided into five groups (n=10 in each group) and were fed a diet supplemented with AUPGA at 0, 20, 50 or 100 mg/kg for three weeks. All mice were weighed and the blood, liver and spleen were collected for further experiments. The results indicated that AUPGA did not significantly affect animal body weight, but significantly increased spleen weight (P<0.05) and decreased liver weight (P<0.05) when compared with the control group. AUPGA significantly increased the T cell (CD3) population at treatments of 20 and 100 mg/kg (P<0.05). However, it only significantly increased the B cell (CD19) population at a treatment of 20 mg/kg (P<0.05). Furthermore, AUPGA at 50 and 100 mg/kg significantly increased the monocyte (CD11b) population and the level of macrophages (Mac-3; P<0.05 for both). AUPGA at 50 and 100 mg/kg significantly promoted macrophage phagocytosis in peripheral blood mononuclear cells (P<0.05), and all doses of AUPGA treatment significantly promoted macrophage phagocytotic activity in the peritoneum (P<0.05). AUPGA treatment significantly decreased natural killer cell activity from splenocytes (P<0.05). Finally, AUPGA treatment at 20 mg/kg treatment significantly promoted T cell proliferation (P<0.05), and treatment at 50 and 100 mg/kg significantly decreased B cell proliferation compared with the control group (P<0.05).

  8. Boron toxicity in rice (Oryza sativa L.). I. Quantitative trait locus (QTL) analysis of tolerance to boron toxicity.

    Science.gov (United States)

    Ochiai, K; Uemura, S; Shimizu, A; Okumoto, Y; Matoh, T

    2008-06-01

    Boron toxicity tolerance of rice plants was studied. Modern japonica subspecies such as Koshihikari, Nipponbare, and Sasanishiki were tolerant, whereas indica subspecies such as Kasalath and IR36 were intolerant to excessive application of boron (B), even though their shoot B contents under B toxicity were not significantly different. Recombinant inbred lines (RILs) of japonica Nekken-1 and indica IR36 were used for quantitative trait locus (QTL) analysis to identify the gene responsible for B toxicity tolerance. A major QTL that could explain 45% of the phenotypic variation was detected in chromosome 4. The QTL was confirmed using a population derived from a recombinant inbred line which is heterogenic at the QTL region. The QTL was also confirmed in other chromosome segment substitution lines (CSSLs).

  9. Association Mapping of Quantitative Trait Loci for Mineral Element Contents in Whole Grain Rice (Oryza sativa L.).

    Science.gov (United States)

    Huang, Yan; Sun, Chengxiao; Min, Jie; Chen, Yaling; Tong, Chuan; Bao, Jinsong

    2015-12-23

    Mineral elements in brown rice grain play an important role in human health. In this study, variations in the content of iron (Fe), zinc (Zn), selenium (Se), cadmium (Cd), and lead (Pb) in 378 accessions of brown rice were investigated, and association mapping was used to detect the quantitative trait loci (QTLs) responsible for the variation. Among seven subpopulations, the mean values of Zn and Cd in the japonica group were significantly higher than in the indica groups. The population structure accounted for from 5.7% (Se) to 22.1% (Pb) of the total variation. Correlation analyses showed that Pb was positively correlated with the other minerals (P rice grain by marker-assisted selection (MAS).

  10. Genetic Architecture of Aluminum Tolerance in Rice (Oryza sativa) Determined through Genome-Wide Association Analysis and QTL Mapping

    Science.gov (United States)

    Famoso, Adam N.; Zhao, Keyan; Clark, Randy T.; Tung, Chih-Wei; Wright, Mark H.; Bustamante, Carlos; Kochian, Leon V.; McCouch, Susan R.

    2011-01-01

    Aluminum (Al) toxicity is a primary limitation to crop productivity on acid soils, and rice has been demonstrated to be significantly more Al tolerant than other cereal crops. However, the mechanisms of rice Al tolerance are largely unknown, and no genes underlying natural variation have been reported. We screened 383 diverse rice accessions, conducted a genome-wide association (GWA) study, and conducted QTL mapping in two bi-parental populations using three estimates of Al tolerance based on root growth. Subpopulation structure explained 57% of the phenotypic variation, and the mean Al tolerance in Japonica was twice that of Indica. Forty-eight regions associated with Al tolerance were identified by GWA analysis, most of which were subpopulation-specific. Four of these regions co-localized with a priori candidate genes, and two highly significant regions co-localized with previously identified QTLs. Three regions corresponding to induced Al-sensitive rice mutants (ART1, STAR2, Nrat1) were identified through bi-parental QTL mapping or GWA to be involved in natural variation for Al tolerance. Haplotype analysis around the Nrat1 gene identified susceptible and tolerant haplotypes explaining 40% of the Al tolerance variation within the aus subpopulation, and sequence analysis of Nrat1 identified a trio of non-synonymous mutations predictive of Al sensitivity in our diversity panel. GWA analysis discovered more phenotype–genotype associations and provided higher resolution, but QTL mapping identified critical rare and/or subpopulation-specific alleles not detected by GWA analysis. Mapping using Indica/Japonica populations identified QTLs associated with transgressive variation where alleles from a susceptible aus or indica parent enhanced Al tolerance in a tolerant Japonica background. This work supports the hypothesis that selectively introgressing alleles across subpopulations is an efficient approach for trait enhancement in plant breeding programs and

  11. Studies on some agronomic and quality characteristics of 271 induced early mutants of rice (Oryza sativa L. cv. Nizersail)

    International Nuclear Information System (INIS)

    Rahman, Mostafizur; Miah, A.J.; Mansur, M.A.; Kaul, A.K.

    1980-01-01

    Nizersail, the most popular, recommended rice variety in Bangladesh, was subjected to gamma-irradiation (10 - 25 kR) or ethyl methane sulfonate (EMS) (0.75 - 1.50%) treatments to obtain the mutants with stiff straw and early maturity. In the M 2 generation, 29 gamma-ray- and 8 EMS-induced mutants were selected mainly for short culm length and earliness. Further selections were made in the segregating M 3 and M 4 populations, and finally 400 plants with short culm length were obtained. These 400 selections were grown in M 5 lines, and 271 of these lines were analyzed for several characters. Heading time had singificantly shifted towards earliness in 40 lines. Yield per plant, 1,000-kernel weight, the length/breadth ratio of kernels, alkali spreading index value (indicator of amylose content) and dye-binding capacity (indicator of protein content) were significantly higher than those in the mother variety in 10 - 30% of the lines examined. However, no positive correlation among these characters was observed. Significant negative correlations were observed between heading time and 1,000-kernel weight, and between yield per plant and dye-binding capacity. These results suggest that the early heading plants may produce fewer tillers with bolder seeds, and that high yielding types may not simultaneously show high protein content. (Kaihara, S.)

  12. Advanced Backcross QTL Analysis for the Whole Plant Growth Duration Salt Tolerance in Rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    CHAI Lu; LI Zhi-kang; ZHANG Jian; PAN Xiao-biao; ZHANG Fan; ZHENG Tian-qing; ZHAO Xiu-qing; WANG Wen-sheng; Ali Jauhar; XU Jian-long

    2014-01-01

    Salinity is a major factor limiting rice yield in coastal areas of Asia. To facilitate breeding salt tolerant rice varieties, the whole-plant growth duration salt tolerance (ST) was genetically dissected by phenotyping two sets of BC2F5 introgression lines (ILs) for four yield traits under severe natural salt stress and non-stress ifled conditions using SSR markers and the methods of advanced backcross QTL (AB-QTL) analysis and selective introgression. Many QTLs affecting four yield traits under salt stress and non-stress conditions were identiifed, most (>90%) of which were clustered in 13 genomic regions of the rice genome and involved in complex epistasis. Most QTLs affecting yield traits were differentially expressed under salt stress and non-stress conditions. Our results suggested that genetics complementarily provides an adequate explanation for the hidden genetic diversity for ST observed in both IL populations. Some promising Huanghuazhan (HHZ) ILs with favorable donor alleles at multiple QTLs and signiifcantly improved yield traits under salt stress and non-stress conditions were identiifed, providing excellent materials and relevant genetic information for improving rice ST by marker-assisted selection (MAS) or genome selection.

  13. Genetic structure and diversity of indigenous rice (Oryza sativa) varieties in the Eastern Himalayan region of Northeast India.

    Science.gov (United States)

    Choudhury, Baharul; Khan, Mohamed Latif; Dayanandan, Selvadurai

    2013-12-01

    The Eastern Himalayan region of Northeast (NE) India is home to a large number of indigenous rice varieties, which may serve as a valuable genetic resource for future crop improvement to meet the ever-increasing demand for food production. However, these varieties are rapidly being lost due to changes in land-use and agricultural practices, which favor agronomically improved varieties. A detailed understanding of the genetic structure and diversity of indigenous rice varieties is crucial for efficient utilization of rice genetic resources and for developing suitable conservation strategies. To explore the genetic structure and diversity of rice varieties in NE India, we genotyped 300 individuals of 24 indigenous rice varieties representing sali, boro, jum and glutinous types, 5 agronomically improved varieties, and one wild rice species (O. rufipogon) using seven SSR markers. A total of 85 alleles and a very high level of gene diversity (0.776) were detected among the indigenous rice varieties of the region. Considerable level of genetic variation was found within indigenous varieties whereas improved varieties were monoporphic across all loci. The comparison of genetic diversity among different types of rice revealed that sali type possessed the highest gene diversity (0.747) followed by jum (0.627), glutinous (0.602) and boro (0.596) types of indigenous rice varieties, while the lowest diversity was detected in agronomically improved varieties (0.459). The AMOVA results showed that 66% of the variation was distributed among varieties indicating a very high level of genetic differentiation in rice varieties in the region. Two major genetically defined clusters corresponding to indica and japonica groups were detected in rice varieties of the region. Overall, traditionally cultivated indigenous rice varieties in NE India showed high levels of genetic diversity comparable to levels of genetic diversity reported from wild rice populations in various parts of the

  14. Open-pit coal-mining effects on rice paddy soil composition and metal bioavailability to Oryza sativa L. plants in Cam Pha, northeastern Vietnam.

    Science.gov (United States)

    Martinez, Raul E; Marquez, J Eduardo; Hòa, Hoàng Thị Bích; Gieré, Reto

    2013-11-01

    This study quantified Cd, Pb, and Cu content, and the soil-plant transfer factors of these elements in rice paddies within Cam Pha, Quang Ninh province, northeastern Vietnam. The rice paddies are located at a distance of 2 km from the large Coc Sau open-pit coal mine. Electron microprobe analysis combined with backscattered electron imaging and energy-dispersive spectroscopy revealed a relatively high proportion of carbon particles rimmed by an iron sulfide mineral (probably pyrite) in the quartz-clay matrix of rice paddy soils at 20-30 cm depth. Bulk chemical analysis of these soils revealed the presence of Cd, Cu, and Pb at concentrations of 0.146±0.004, 23.3±0.1, and 23.5±0.1 mg/kg which exceeded calculated background concentrations of 0.006±0.004, 1.9±0.5, and 2.4±1.5 mg/kg respectively at one of the sites. Metals and metalloids in Cam Pha rice paddy soils, including As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn, were found in concentrations ranging from 0.2±0.1 to 140±3 mg/kg, which were in close agreement with toxic metal contents in mine tailings and Coc Sau coal samples, suggesting mining operations as a major cause of paddy soil contamination. Native and model Oryza sativa L. rice plants were grown in the laboratory in a growth medium to which up to 1.5 mg/kg of paddy soil from Cam Pha was added to investigate the effects on plant growth. A decrease in growth by up to 60% with respect to a control sample was found for model plants, whereas a decrease of only 10% was observed for native (Nep cai hoa vang variety) rice plants. This result suggests an adaptation of native Cam Pha rice plants to toxic metals in the agricultural lands. The Cd, Cu, and Pb contents of the native rice plants from Cam Pha paddies exceeded permitted levels in foods. Cadmium and Pb were highest in the rice plant roots with concentrations of 0.84±0.02 and 7.7±0.3 mg/kg, suggesting an intake of these metals into the rice plant as shown, for example, by Cd and Pb concentrations of 0

  15. Sensitization and allergy to Cannabis sativa leaves in a population of tomato (Lycopersicon esculentum)-sensitized patients.

    Science.gov (United States)

    de Larramendi, Carlos Hernando; Carnés, Jerónimo; García-Abujeta, José Luís; García-Endrino, Ana; Muñoz-Palomino, Elena; Huertas, Angel Julio; Fernández-Caldas, Enrique; Ferrer, Angel

    2008-01-01

    Cases of allergy to Cannabis sativa have occasionally been reported, but both the allergenic profile and eventual cross-reactivity pattern remain unknown. To analyze the allergenic profile of a population of patients from Spain sensitized to C. sativa and to characterize the C. sativa leaf extract. A total of 32 subjects were enrolled in the study: group A, 10 individuals sensitized to tomato, reporting reactions by contact or inhalation to Cannabis; group B, 14 individuals sensitized to tomato, without reactions to Cannabis; group C, 8 individuals not sensitized to tomato and without reactions to Cannabis. Sensitivity to Cannabis, tomato and peach peel, Platanus hybrida and Artemisia vulgaris pollen extracts was measured by skin tests and specific IgE. Individual immunoblots and inhibition experiments with a pool of sera were conducted. All tomato-sensitized subjects (and 1 negative) had positive skin tests to C. sativa leaves and hashish. Specific IgE to C. sativa and peach peel was more common than to tomato. Immunoblot experiments showed 2 prominent bands of 10 and 14 kDa and 2 weakly recognized bands of 30 and 45 kDa. Tomato, peach and A. vulgaris extracts inhibited most of the bands present in C. sativa. P. hybrida inhibited only the high-molecular-weight bands. Sensitization to C. sativa with or without symptoms is frequent among patients in Spain sensitized to tomato. C. sativa leaves are a potential allergenic source and their allergens may cross-react with other allergenic sources from plants (fruit peels and pollen). (c) 2008 S. Karger AG, Basel

  16. indica rice (Oryza sativa L.)

    African Journals Online (AJOL)

    Jane

    2011-07-18

    Jul 18, 2011 ... fresh weight, regeneration, proline level and total protein content in salt sensitive indica rice cv. IR 64. For callus ... INTRODUCTION. Salinity is one of the ... Proline is reported to reduce the enzyme denaturation caused due.

  17. Lowered Diversity and Increased Inbreeding Depression within Peripheral Populations of Wild Rice Oryza rufipogon.

    Science.gov (United States)

    Gao, Li-Zhi; Gao, Cheng-Wen

    2016-01-01

    The distribution of genetic variability from the interior towards the periphery of a species' range is of great interest to evolutionary biologists. Although it has been long presumed that population genetic variation should decrease as a species' range is approached, results of empirical investigations still remain ambiguous. Knowledge regarding patterns of genetic variability as well as affected factors is particularly not conclusive in plants. To determine genetic divergence in peripheral populations of the wild rice Oryza rufipogon Griff. from China, genetic diversity and population structure were studied in five northern & northeastern peripheral and 16 central populations using six microsatellite loci. We found that populations resided at peripheries of the species possessed markedly decreased microsatellite diversity than those located in its center. Population size was observed to be positively correlated with microsatellite diversity. Moreover, there are significantly positive correlations between levels of microsatellite diversity and distances from the northern and northeastern periphery of this species. To investigate genetic structure and heterozygosity variation between generations of O. rufipogon, a total of 2382 progeny seeds from 186 maternal families were further assayed from three peripheral and central populations, respectively. Peripheral populations exhibited significantly lower levels of heterozygosities than central populations for both seed and maternal generations. In comparisons with maternal samples, significantly low observed heterozygosity (HO) and high heterozygote deficit within populations (FIS) values were detected in seed samples from both peripheral and central populations. Significantly lower observed heterozygosity (HO) and higher FIS values were further observed in peripheral populations than those in central populations for seed samples. The results indicate an excess of homozygotes and thus high inbreeding depression in

  18. Molecular Diversity and Population Structure of a Worldwide Collection of Cultivated Tetraploid Alfalfa (Medicago sativa subsp. sativa L.) Germplasm as Revealed by Microsatellite Markers.

    Science.gov (United States)

    Qiang, Haiping; Chen, Zhihong; Zhang, Zhengli; Wang, Xuemin; Gao, Hongwen; Wang, Zan

    2015-01-01

    Information on genetic diversity and population structure of a tetraploid alfalfa collection might be valuable in effective use of the genetic resources. A set of 336 worldwide genotypes of tetraploid alfalfa (Medicago sativa subsp. sativa L.) was genotyped using 85 genome-wide distributed SSR markers to reveal the genetic diversity and population structure in the alfalfa. Genetic diversity analysis identified a total of 1056 alleles across 85 marker loci. The average expected heterozygosity and polymorphism information content values were 0.677 and 0.638, respectively, showing high levels of genetic diversity in the cultivated tetraploid alfalfa germplasm. Comparison of genetic characteristics across chromosomes indicated regions of chromosomes 2 and 3 had the highest genetic diversity. A higher genetic diversity was detected in alfalfa landraces than that of wild materials and cultivars. Two populations were identified by the model-based population structure, principal coordinate and neighbor-joining analyses, corresponding to China and other parts of the world. However, lack of strictly correlation between clustering and geographic origins suggested extensive germplasm exchanges of alfalfa germplasm across diverse geographic regions. The quantitative analysis of the genetic diversity and population structure in this study could be useful for genetic and genomic analysis and utilization of the genetic variation in alfalfa breeding.

  19. A rare sugar, d-allose, confers resistance to rice bacterial blight with upregulation of defense-related genes in Oryza sativa.

    Science.gov (United States)

    Kano, Akihito; Gomi, Kenji; Yamasaki-Kokudo, Yumiko; Satoh, Masaru; Fukumoto, Takeshi; Ohtani, Kouhei; Tajima, Shigeyuki; Izumori, Ken; Tanaka, Keiji; Ishida, Yutaka; Tada, Yasuomi; Nishizawa, Yoko; Akimitsu, Kazuya

    2010-01-01

    We investigated responses of rice plant to three rare sugars, d-altrose, d-sorbose, and d-allose, due to establishment of mass production methods for these rare sugars. Root growth and shoot growth were significantly inhibited by d-allose but not by the other rare sugars. A large-scale gene expression analysis using a rice microarray revealed that d-allose treatment causes a high upregulation of many defense-related, pathogenesis-related (PR) protein genes in rice. The PR protein genes were not upregulated by other rare sugars. Furthermore, d-allose treatment of rice plants conferred limited resistance of the rice against the pathogen Xanthomonas oryzae pv. oryzae but the other tested sugars did not. These results indicate that d-allose has a growth inhibitory effect but might prove to be a candidate elicitor for reducing disease development in rice.

  20. Rice black streaked dwarf virus P7-2 forms a SCF complex through binding to Oryza sativa SKP1-like proteins, and interacts with GID2 involved in the gibberellin pathway.

    Directory of Open Access Journals (Sweden)

    Tao Tao

    Full Text Available As a core subunit of the SCF complex that promotes protein degradation through the 26S proteasome, S-phase kinase-associated protein 1 (SKP1 plays important roles in multiple cellular processes in eukaryotes, including gibberellin (GA, jasmonate, ethylene, auxin and light responses. P7-2 encoded by Rice black streaked dwarf virus (RBSDV, a devastating viral pathogen that causes severe symptoms in infected plants, interacts with SKP1 from different plants. However, whether RBSDV P7-2 forms a SCF complex and targets host proteins is poorly understood. In this study, we conducted yeast two-hybrid assays to further explore the interactions between P7-2 and 25 type I Oryza sativa SKP1-like (OSK proteins, and found that P7-2 interacted with eight OSK members with different binding affinity. Co-immunoprecipitation assay further confirmed the interaction of P7-2 with OSK1, OSK5 and OSK20. It was also shown that P7-2, together with OSK1 and O. sativa Cullin-1, was able to form the SCF complex. Moreover, yeast two-hybrid assays revealed that P7-2 interacted with gibberellin insensitive dwarf2 (GID2 from rice and maize plants, which is essential for regulating the GA signaling pathway. It was further demonstrated that the N-terminal region of P7-2 was necessary for the interaction with GID2. Overall, these results indicated that P7-2 functioned as a component of the SCF complex in rice, and interaction of P7-2 with GID2 implied possible roles of the GA signaling pathway during RBSDV infection.

  1. Rice black streaked dwarf virus P7-2 forms a SCF complex through binding to Oryza sativa SKP1-like proteins, and interacts with GID2 involved in the gibberellin pathway.

    Science.gov (United States)

    Tao, Tao; Zhou, Cui-Ji; Wang, Qian; Chen, Xiang-Ru; Sun, Qian; Zhao, Tian-Yu; Ye, Jian-Chun; Wang, Ying; Zhang, Zong-Ying; Zhang, Yong-Liang; Guo, Ze-Jian; Wang, Xian-Bing; Li, Da-Wei; Yu, Jia-Lin; Han, Cheng-Gui

    2017-01-01

    As a core subunit of the SCF complex that promotes protein degradation through the 26S proteasome, S-phase kinase-associated protein 1 (SKP1) plays important roles in multiple cellular processes in eukaryotes, including gibberellin (GA), jasmonate, ethylene, auxin and light responses. P7-2 encoded by Rice black streaked dwarf virus (RBSDV), a devastating viral pathogen that causes severe symptoms in infected plants, interacts with SKP1 from different plants. However, whether RBSDV P7-2 forms a SCF complex and targets host proteins is poorly understood. In this study, we conducted yeast two-hybrid assays to further explore the interactions between P7-2 and 25 type I Oryza sativa SKP1-like (OSK) proteins, and found that P7-2 interacted with eight OSK members with different binding affinity. Co-immunoprecipitation assay further confirmed the interaction of P7-2 with OSK1, OSK5 and OSK20. It was also shown that P7-2, together with OSK1 and O. sativa Cullin-1, was able to form the SCF complex. Moreover, yeast two-hybrid assays revealed that P7-2 interacted with gibberellin insensitive dwarf2 (GID2) from rice and maize plants, which is essential for regulating the GA signaling pathway. It was further demonstrated that the N-terminal region of P7-2 was necessary for the interaction with GID2. Overall, these results indicated that P7-2 functioned as a component of the SCF complex in rice, and interaction of P7-2 with GID2 implied possible roles of the GA signaling pathway during RBSDV infection.

  2. Purification, crystallization and preliminary X-ray analysis of recombinant betaine aldehyde dehydrogenase 2 (OsBADH2), a protein involved in jasmine aroma, from Thai fragrant rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Kuaprasert, Buabarn; Silprasit, Kun; Horata, Natharinee; Khunrae, Pongsak; Wongpanya, Ratree; Boonyalai, Nonlawat; Vanavichit, Apichart; Choowongkomon, Kiattawee

    2011-01-01

    Crystals of betaine aldehyde dehydrogenase 2 from rice (O. sativa L.) belonged to a C-centred orthorhombic space group and diffraceted X-rays to 2.6 Å resolution. Fragrant rice (Oryza sativa L.) betaine aldehyde dehydrogenase 2 (OsBADH2) is a key enzyme in the synthesis of fragrance aroma compounds. The extremely low activity of OsBADH2 in catalyzing the oxidation of acetaldehyde is believed to be crucial for the accumulation of the volatile compound 2-acetyl-1-pyrroline (2AP) in many scented plants, including fragrant rice. Recombinant fragrant rice OsBADH2 was expressed in Escherichia coli as an N-terminal hexahistidine fusion protein, purified using Ni Sepharose affinity chromatography and crystallized using the microbatch method. Initial crystals were obtained within 24 h using 0.1 M Tris pH 8.5 with 30%(w/v) PEG 4000 and 0.2 M magnesium chloride as the precipitating agent at 291 K. Crystal quality was improved when the enzyme was cocrystallized with NAD + . Improved crystals were grown in 0.1 M HEPES pH 7.4, 24%(w/v) PEG 4000 and 0.2 M ammonium chloride and diffracted to beyond 2.95 Å resolution after being cooled in a stream of N 2 immediately prior to X-ray diffraction experiments. The crystals belonged to space group C222 1 , with unit-cell parameters a = 66.03, b = 183.94, c = 172.28 Å. An initial molecular-replacement solution has been obtained and refinement is in progress

  3. Dye characteristics of Zingiber officinale var rubrum, Cinnamomum zaylanicum, Curcuma longa L., Oryza sativa L. Indica in dye sensitized solar cell (DSSC)

    Science.gov (United States)

    Cari; Mahfudli Fadli, U.; Bayu Prasada, A.; Supriyanto, A.

    2017-01-01

    The aims of the research to were know performance of DSSC using the dye of Zingiber, Cinnamomum, Curcuma, and Oryza as a photosensitizer with a variation of dye deposition area with spin coating techniques. The structure of the samples as a sandwich consisting of the working electrode (TiO2), dye, electrodes of platinum (Pt) and the electrolyte sandwiched between two electrodes. Test absorbance dye using UV-Visible Spectrophotometer Lambda 25, using a two-point conductivity test probes El Kahfi 100 and characterization test IV using a Keithley 2602A. For Zingiber results showed that absorbance at 243 nm and 279 nm, photoconductivity of 0.29 Ω-1m-1 and the efficiency is 0.015% on 0.5 cm2. Cinnamomum results showed that absorbance at 253 nm and 403 nm, photoconductivity of 0.11 Ω-1m-1 and the efficiency is 0.002% on 3 cm2. Curcuma results showed that absorbance at 243 nm and 422 nm, photoconductivity of 0.177 Ω-1m-1 and the efficiency is 0.072% on 3 cm2. Oryza results showed that absorbance at 240 nm and 423 nm, photoconductivity of 0.21 Ω-1m-1 and the efficiency is 0.04% on 2.25 cm2. Best absorbance value was obtained from Oryza dye; the highest photoconductivity was obtained from Zingiber dye, and the highest efficiency was obtained from Curcuma dye.

  4. Dye characteristics of Zingiber officinale var rubrum, Cinnamomum zaylanicum, Curcuma longa L., Oryza sativa L. Indica in dye sensitized solar cell (DSSC)

    International Nuclear Information System (INIS)

    Cari; Fadli, U. Mahfudli; Prasada, A. Bayu; Supriyanto, A.

    2017-01-01

    The aims of the research to were know performance of DSSC using the dye of Zingiber , Cinnamomum , Curcuma , and Oryza as a photosensitizer with a variation of dye deposition area with spin coating techniques. The structure of the samples as a sandwich consisting of the working electrode (TiO 2 ), dye, electrodes of platinum (Pt) and the electrolyte sandwiched between two electrodes. Test absorbance dye using UV-Visible Spectrophotometer Lambda 25, using a two-point conductivity test probes El Kahfi 100 and characterization test IV using a Keithley 2602A. For Zingiber results showed that absorbance at 243 nm and 279 nm, photoconductivity of 0.29 Ω -1 m -1 and the efficiency is 0.015% on 0.5 cm 2 . Cinnamomum results showed that absorbance at 253 nm and 403 nm, photoconductivity of 0.11 Ω -1 m -1 and the efficiency is 0.002% on 3 cm 2 . Curcuma results showed that absorbance at 243 nm and 422 nm, photoconductivity of 0.177 Ω -1 m -1 and the efficiency is 0.072% on 3 cm 2 . Oryza results showed that absorbance at 240 nm and 423 nm, photoconductivity of 0.21 Ω -1 m -1 and the efficiency is 0.04% on 2.25 cm 2 . Best absorbance value was obtained from Oryza dye; the highest photoconductivity was obtained from Zingiber dye, and the highest efficiency was obtained from Curcuma dye. (paper)

  5. Low doses of six toxicants change plant size distribution in dense populations of Lactuca sativa.

    Science.gov (United States)

    Belz, Regina G; Patama, Marjo; Sinkkonen, Aki

    2018-08-01

    Toxicants are known to have negligible or stimulatory, i.e. hormetic, effects at low doses below those that decrease the mean response of a plant population. Our earlier observations indicated that at such low toxicant doses the growth of very fast- and slow-growing seedlings is selectively altered, even if the population mean remains constant. Currently, it is not known how common these selective low-dose effects are, whether they are similar among fast- and slow-growing seedlings, and whether they occur concurrently with hormetic effects. We tested the response of Lactuca sativa in complete dose-response experiments to six different toxicants at doses that did not decrease population mean and beyond. The tested toxicants were IAA, parthenin, HHCB, 4-tert-octylphenol, glyphosate, and pelargonic acid. Each experiment consisted of 14,400-16,800 seedlings, 12-14 concentrations, 24 replicates per concentration and 50 germinated seeds per replicate. We analyzed the commonness of selective low-dose effects and explored if toxic effects and hormetic stimulation among fast- and slow-growing individuals occurred at the same concentrations as they occur at the population level. Irrespective of the observed response pattern and toxicant, selective low-dose effects were found. Toxin effects among fast-growing individuals usually started at higher doses compared to the population mean, while the opposite was found among slow-growing individuals. Very low toxin exposures tended to homogenize plant populations due to selective effects, while higher, but still hormetic doses tended to heterogenize plant populations. Although the extent of observed size segregation varied with the specific toxin tested, we conclude that a dose-dependent alteration in size distribution of a plant population may generally apply for many toxin exposures. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko; Tanaka, Tsuyoshi; Ohyanagi, Hajime; Hsing, Yue-Ie C.; Itoh, Takeshi

    2018-01-01

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  7. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko

    2018-02-14

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  8. Authenticity of rice (Oryza sativa L.) geographical origin based on analysis of C, N, O and S stable isotope ratios: a preliminary case report in Korea, China and Philippine.

    Science.gov (United States)

    Chung, Ill-Min; Kim, Jae-Kwang; Prabakaran, Mayakrishnan; Yang, Jin-Hee; Kim, Seung-Hyun

    2016-05-01

    Although rice (Oryza sativa L.) is the third largest food crop, relatively fewer studies have been reported on rice geographical origin based on light element isotope ratios in comparison with other foods such as wine, beef, juice, oil and milk. Therefore this study tries to discriminate the geographical origin of the same rice cultivars grown in different Asian countries using the analysis of C, N, O and S stable isotope ratios and chemometrics. The δ(15) NAIR , δ(18) OVSMOW and δ(34) SVCDT values of brown rice were more markedly influenced by geographical origin than was the δ(13) CVPDB value. In particular, the combination of δ(18) OVSMOW and δ(34) SVCDT more efficiently discriminated rice geographical origin than did the remaining combinations. Principal component analysis (PCA) revealed a clear discrimination between different rice geographical origins but not between rice genotypes. In particular, the first components of PCA discriminated rice cultivated in the Philippines from rice cultivated in China and Korea. The present findings suggest that analysis of the light element isotope composition combined with chemometrics can be potentially applicable to discriminate rice geographical origin and also may provide a valuable insight into the control of improper or fraudulent labeling regarding the geographical origin of rice worldwide. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  9. Modulation of proton pumping across proteoliposome membranes reconstituted with tonoplast H(+)-ATPase from cultured rice (Oryza sativa L. var. Boro) cells by acyl steryl glucoside and steryl glucoside.

    Science.gov (United States)

    Yamaguchi, Mineo; Kasamo, Kunihiro

    2002-07-01

    Tonoplast H(+)-ATPase purified from cultured rice cells (Oryza sativa L. var. Boro) was reconstituted into asolectin liposomes containing steryl glucoside (SG) or acyl steryl glucoside (ASG), and the effects of SG and ASG on proton pumping, ATP-hydrolysis activity and proton permeability of the proteoliposome membranes were investigated. In the proteoliposomes containing 10 mol% SG, proton pumping and ATP-hydrolysis activity were increased to around 140% of those in SG-free proteoliposomes. In the proteoliposomes containing ASG, proton pumping and ATP-hydrolysis activity were decreased to one-tenth of those in ASG-free proteoliposomes at 15 mol% ASG; however, activity increased again slightly in the range between 20 and 40 mol% ASG. The change in proton pumping across the proteoliposome membrane is not due to a change of proteoliposome size nor to the location of the catalytic site of the tonoplast H(+)-ATPase in the proteoliposomes. SG and ASG also reduced the passive proton permeability of the proteoliposomes. These results show that SG and ASG modulate proton pumping across the tonoplast toward stimulation and depression, respectively, and they reduce the passive proton permeability of the tonoplast.

  10. Study of radio-restoration by various mineral salts and silice wich products (Tuf and Pouzzolane) of rice embryos (oryza-sativa L, Cigalon variety) exposed to cobalt 60 gamma rays

    International Nuclear Information System (INIS)

    Mouthia-Khadija.

    1981-12-01

    Mutagenic treatments produce a large number of mutants per unit time and are used for plant improvement. However these treatments cause damage to cells. To counteract this radio-induced damage 2 methods are being tried: - Protection, which consists in the supply of an active product before application of mutagenic agents; - Restoration, which tries to repair the damage after mutagenic treatment. This work is devoted to restoration processes. Technique for the isolation and culture on a suitable nutrient of rice embryos (oryza sativa L, Cigalon variety) separated from non-irradiated caryopses were developed first. By separating out the embryo in this way it is possible to study in vitro the interactions between the embryo and the rest of the caryopsis (albumin + pericarp). The effects of radiations on embryos from caryopses exposed to cobalt 60 gamma rays were measured next, then the action of certain inorganic elements contained in the caryopsis tissues was analysed. On the basis of the first results obtained the differences in response between plantlets from embryos irradiated or otherwise treated or not either by zinc sulphate or by very silice-rich volcanic products (Tuf and Pouzzolane), were examined by chemical analysis techniques. These tests have allowed the detection of ionic changes induced by irradiation during the different stages of plant development and led to a better estimate of the radio-restoration mechanisms brought about by the various chemical compounds used [fr

  11. Isolation and Expression analysis of OsPME1, encoding for a putative Pectin Methyl Esterase from Oryza sativa (subsp. indica)

    OpenAIRE

    Kanneganti, Vydehi; Gupta, Aditya Kumar

    2009-01-01

    Pectin Methyl Esterases (PMEs) play an essential role during plant development by affecting the mechanical properties of the plant cell walls. Recent studies indicated that PMEs play important role in pollen tube development. In this study, we isolated a 1.3 kb cDNA clone from rice panicle cDNA library. It contained a 1038 bp of open reading frame (ORF) encoding for a putative pectin methyl esterase of 345 aminoacids with a 20 aminoacid signal peptide and was hence designated as OsPME1 (Oryza...

  12. WATER DEFICIT EFFECT ON YIELD AND FORAGE QUALITY OF MEDICAGO SATIVA POPULATIONS UNDER FIELD CONDITIONS IN MARRAKESH AREA (MOROCCO)

    OpenAIRE

    Mohamed FARISSI; Cherki GHOULAM; Abdelaziz BOUIZGAREN

    2014-01-01

    The present study focused the effect of water deficit on agronomic potential and some traits related to forage quality in plants of Moroccan Alfalfa (Medicago sativa L.) populations (Taf 1, Taf 2, Dem and Tata) originated from Oasis and High Atlas of Morocco and an introduced variety from Australia (Siriver). The experiment was conducted under field conditions in experimental station of INRA-Marrakech and under two irrigation treatments. The first treatment was normal irrigation, providing an...

  13. OsLOL1, a C2C2-type zinc finger protein, interacts with OsbZIP58 to promote seed germination through the modulation of gibberellin biosynthesis in Oryza sativa.

    Science.gov (United States)

    Wu, Jiahe; Zhu, Chuanfeng; Pang, Jinhuan; Zhang, Xiangrong; Yang, Chunlin; Xia, Guixian; Tian, Yingchuan; He, Chaozu

    2014-12-01

    Seed germination is a key developmental process in the plant life cycle that is influenced by various environmental cues and phytohormones through gene expression and a series of metabolism pathways. In the present study, we investigated a C2C2-type finger protein, OsLOL1, which promotes gibberellin (GA) biosynthesis and affects seed germination in Oryza sativa (rice). We used OsLOL1 antisense and sense transgenic lines to explore OsLOL1 functions. Seed germination timing in antisense plants was restored to wild type when exogenous GA3 was applied. The reduced expression of the GA biosynthesis gene OsKO2 and the accumulation of ent-kaurene were observed during germination in antisense plants. Based on yeast two-hybrid and firefly luciferase complementation analyses, OsLOL1 interacted with the basic leucine zipper protein OsbZIP58. The results from electrophoretic mobility shift and dual-luciferase reporter assays showed that OsbZIP58 binds the G-box cis-element of the OsKO2 promoter and activates LUC reporter gene expression, and that interaction between OsLOL1 and OsbZIP58 activates OsKO2 gene expression. In addition, OsLOL1 decreased SOD1 gene expression and accelerated programmed cell death (PCD) in the aleurone layer of rice grains. These findings demonstrate that the interaction between OsLOL1 and OsbZIP58 influences GA biosynthesis through the activation of OsKO2 via OsbZIP58, thereby stimulating aleurone PCD and seed germination. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  14. Uncovering a Nuisance Influence of a Phenological Trait of Plants Using a Nonlinear Structural Equation: Application to Days to Heading and Culm Length in Asian Cultivated Rice (Oryza Sativa L.).

    Science.gov (United States)

    Onogi, Akio; Ideta, Osamu; Yoshioka, Takuma; Ebana, Kaworu; Yamasaki, Masanori; Iwata, Hiroyoshi

    2016-01-01

    Phenological traits of plants, such as flowering time, are linked to growth phase transition. Thus, phenological traits often influence other traits through the modification of the duration of growth period. This influence is a nuisance in plant breeding because it hampers genetic evaluation of the influenced traits. Genetic effects on the influenced traits have two components, one that directly affects the traits and one that indirectly affects the traits via the phenological trait. These cannot be distinguished by phenotypic evaluation and ordinary linear regression models. Consequently, if a phenological trait is modified by introgression or editing of the responsible genes, the phenotypes of the influenced traits can change unexpectedly. To uncover the influence of the phenological trait and evaluate the direct genetic effects on the influenced traits, we developed a nonlinear structural equation (NSE) incorporating a nonlinear influence of the phenological trait. We applied the NSE to real data for cultivated rice (Oryza sativa L.): days to heading (DH) as a phenological trait and culm length (CL) as the influenced trait. This showed that CL of the cultivars that showed extremely early heading was shortened by the strong influence of DH. In a simulation study, it was shown that the NSE was able to infer the nonlinear influence and direct genetic effects with reasonable accuracy. However, the NSE failed to infer the linear influence in this study. When no influence was simulated, an ordinary bi-trait linear model (OLM) tended to infer the genetic effects more accurately. In such cases, however, by comparing the NSE and OLM using an information criterion, we could assess whether the nonlinear assumption of the NSE was appropriate for the data analyzed. This study demonstrates the usefulness of the NSE in revealing the phenotypic influence of phenological traits.

  15. Short-chain chlorinated paraffins in soil, paddy seeds (Oryza sativa) and snails (Ampullariidae) in an e-waste dismantling area in China: Homologue group pattern, spatial distribution and risk assessment.

    Science.gov (United States)

    Yuan, Bo; Fu, Jianjie; Wang, Yawei; Jiang, Guibin

    2017-01-01

    Short-chain chlorinated paraffins (SCCPs) in multi-environmental matrices are studied in Taizhou, Zhejiang Province, China, which is a notorious e-waste dismantling area. The investigated matrices consist of paddy field soil, paddy seeds (Oryza sativa, separated into hulls and rice unpolished) and apple snails (Ampullariidae, inhabiting the paddy fields). The sampling area covered a 65-km radius around the contamination center. C 10 and C 11 are the two predominant homologue groups in the area, accounting for about 35.7% and 33.0% of total SCCPs, respectively. SCCPs in snails and hulls are generally higher than in soil samples (30.4-530 ng/g dw), and SCCPs in hulls are approximate five times higher than in corresponding rice samples (4.90-55.1 ng/g dw). Homologue pattern analysis indicates that paddy seeds (both hull and rice) tend to accumulate relatively high volatile SCCP homologues, especially the ones with shorter carbon chain length, while snails tend to accumulate relatively high lipophilic homologues, especially the ones with more substituted chlorines. SCCPs in both paddy seeds and snails are linearly related to those in the soil. The e-waste dismantling area, which covers a radius of approximate 20 km, shows higher pollution levels for SCCPs according to their spatial distribution in four matrices. The preliminary assessment indicates that SCCP levels in local soils pose no significant ecological risk for soil dwelling organisms, but higher risks from dietary exposure of SCCPs are suspected for people living in e-waste dismantling area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. qEMF3, a novel QTL for the early-morning flowering trait from wild rice, Oryza officinalis, to mitigate heat stress damage at flowering in rice, O. sativa.

    Science.gov (United States)

    Hirabayashi, Hideyuki; Sasaki, Kazuhiro; Kambe, Takashi; Gannaban, Ritchel B; Miras, Monaliza A; Mendioro, Merlyn S; Simon, Eliza V; Lumanglas, Patrick D; Fujita, Daisuke; Takemoto-Kuno, Yoko; Takeuchi, Yoshinobu; Kaji, Ryota; Kondo, Motohiko; Kobayashi, Nobuya; Ogawa, Tsugufumi; Ando, Ikuo; Jagadish, Krishna S V; Ishimaru, Tsutomu

    2015-03-01

    A decline in rice (Oryza sativa L.) production caused by heat stress is one of the biggest concerns resulting from future climate change. Rice spikelets are most susceptible to heat stress at flowering. The early-morning flowering (EMF) trait mitigates heat-induced spikelet sterility at the flowering stage by escaping heat stress during the daytime. We attempted to develop near-isogenic lines (NILs) for EMF in the indica-type genetic background by exploiting the EMF locus from wild rice, O. officinalis (CC genome). A stable quantitative trait locus (QTL) for flower opening time (FOT) was detected on chromosome 3. A QTL was designated as qEMF3 and it shifted FOT by 1.5-2.0 h earlier for cv. Nanjing 11 in temperate Japan and cv. IR64 in the Philippine tropics. NILs for EMF mitigated heat-induced spikelet sterility under elevated temperature conditions completing flower opening before reaching 35°C, a general threshold value leading to spikelet sterility. Quantification of FOT of cultivars popular in the tropics and subtropics did not reveal the EMF trait in any of the cultivars tested, suggesting that qEMF3 has the potential to advance FOT of currently popular cultivars to escape heat stress at flowering under future hotter climates. This is the first report to examine rice with the EMF trait through marker-assisted breeding using wild rice as a genetic resource. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. Actinobacteria Associated With Arbuscular Mycorrhizal Funneliformis mosseae Spores, Taxonomic Characterization and Their Beneficial Traits to Plants: Evidence Obtained From Mung Bean (Vigna radiata) and Thai Jasmine Rice (Oryza sativa)

    Science.gov (United States)

    Lasudee, Krisana; Tokuyama, Shinji; Lumyong, Saisamorn; Pathom-aree, Wasu

    2018-01-01

    In this study, we report on the isolation of actinobacteria obtained from spores of Funneliformis mosseae and provide evidence for their potential in agricultural uses as plant growth promoters in vitro and in vivo. Actinobacteria were isolated from spores of F. mosseae using the dilution plate technique and media designed for the selective isolation of members of specific actinobacterial taxa. Six strains namely 48, S1, S3, S4, S4-1 and SP, were isolated and identified based on16S rRNA gene sequences. Phylogenetic analysis showed that isolate SP belonged to the genus Pseudonocardia with P. nantongensis KLBMP 1282T as its closest neighbor. The remaining isolates belonged to the genus Streptomyces. Two isolates, 48 and S3 were most closely related to S. thermocarboxydus DSM 44293T. Isolates S4 and S4-1 shared the highest 16S RNA gene similarity with S. pilosus NBRC 127772T. Isolate S1 showed its closest relationship with the type strain of S. spinoverrucosus NBRC14228T. The ability of these isolates to produce indole-3-acetic acid (IAA), siderophores and the ability to solubilize phosphate in vitro were examined. All isolates produced siderophores, four isolates produced IAA and two isolates solubilized inorganic phosphate at varying levels. S. thermocarboxydus isolate S3 showed the highest IAA production with high activities of phosphate solubilization and siderophore production. The inoculation of mung beans (Vigna radiata) with this strain resulted in a significant increase in fresh weight, root length and total length as an effect of IAA production. In an experiment with rice (Oryza sativa), S. thermocarboxydus isolate S3 promoted the growth of rice plants grown in low nutritional soil under induced drought stress. This report supports the view that the inoculation of rice with plant growth promoting actinobacteria mitigates some adverse effects of low nutrient and drought stress on rice. PMID:29942292

  18. Nuclear and chloroplast diversity and phenotypic distribution of rice (Oryza sativa L.) germplasm from the democratic people’s republic of Korea (DPRK; North Korea)

    Science.gov (United States)

    2014-01-01

    Background Rice accounts for 43% of staple food production in the Democratic People’s Republic of Korea (DPRK). The most widely planted rice varieties were developed from a limited number of ancestral lines that were repeatedly used as parents in breeding programs. However, detailed pedigrees are not publicly available and little is known about the genetic, phenotypic, and geographical variation of DPRK varieties. Results We evaluated 80 O. sativa accessions from the DPRK, consisting of 67 improved varieties and 13 landraces. Based on nuclear SSR analysis, we divide the varieties into two genetic groups: Group 1 corresponds to the temperate japonica subpopulation and represents 78.75% of the accessions, while Group 2 shares recent ancestry with indica varieties. Interestingly, members of Group 1 are less diverse than Group 2 at the nuclear level, but are more diverse at the chloroplast level. All Group 2 varieties share a single Japonica maternal-haplotype, while Group 1 varieties trace maternal ancestry to both Japonica and Indica. Phenotypically, members of Group 1 have shorter grains than Group 2, and varieties from breeding programs have thicker and wider grains than landraces. Improved varieties in Group 1 also show similar and/or better levels of cold tolerance for most traits, except for spikelet number per panicle. Finally, geographic analysis demonstrates that the majority of genetic variation is located within regions that have the most intensive rice cultivation, including the Western territories near the capital city Pyungyang. This is consistent with the conscious and highly centralized role of human selection in determining local dispersion patterns of rice in the DPRK. Conclusions Diversity studies of DPRK rice germplasm revealed two genetic groups. The most widely planted group has a narrow genetic base and would benefit from the introduction of new genetic variation from cold tolerant landraces, wild accessions, and/or cultivated gene pools to

  19. ISSR Analysis on Genetic Diversity of the 34 Populations of Oryza meyeriana Distributing in Yunnan Province, China

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    Ya-tao WAN

    2008-03-01

    Full Text Available The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill. distributed in Yunnan Province, China was analyzed using 13 inter-simple sequence repeat (ISSR markers. A total of 168 bands were amplified, of which 135 polymorphic bands were discovered and the percentage of polymorphic bands (PPB was 80.36%. A genetic diversity was revealed as Nei's gene diversity (H = 0.2666 and Shannon information index (I = 0.4028 at population level. The 34 populations were divided into different groups based on administrative regions, latitude and longitudes, river areas, altitudes of their origins, and their indexes such as Na (number of alleles, Ne (effective number of alleles, H, I and PPB were calculated. Richer genetic diversity was found in the wild rice populations distributed in Simao Prefecture than that in Lingcang Prefecture or Xishuangbanna Prefecture whereas the least genetic diversity was in Baoshan Prefecture or Dehong Prefecture. Rich genetic diversity was also discovered in the wild rice populations originated from higher than 710 m altitude around the middle and lower reaches of the Lancang River belonging to the Pacific Ocean drainage system. The 34 populations could be classified into two groups, one group covered the wild rice distributing in Simao Prefecture only while the other group covered ones in Lingcang, Xishuangbanna and Dehong Prefectures. The issue on how to effectively conserve the wild rice germplasm was discussed.

  20. Involvement of NADPH oxidase isoforms in the production of O2− manipulated by ABA in the senescing leaves of early-senescence-leaf (esl) mutant rice (Oryza sativa)

    Science.gov (United States)

    Wang, Fubiao; Zhao, Qian; Liu, Jianchao; Cheng, Fangmin

    2018-01-01

    In this study, the differences in reactive oxygen species (ROS) generation and abscisic acid (ABA) accumulation in senescing leaves were investigated by early-senescence-leaf (esl) mutant and its wild type, to clarify the relationship among ABA levels, ROS generation, and NADPH oxidase (Nox) in senescing leaves of rice (Oryza sativa). The temporal expression levels of OsNox isoforms in senescing leaves and their expression patterns in response to ABA treatment were determined through quantitative real-time reverse transcription PCR (qRT-PCR). Results showed that the flag leaf of the esl mutant generated more O2- concentrations and accumulated higher ABA levels than the wild-type cultivar did in the grain-filling stage. Exogenous ABA treatment induced O2- generation; however, it was depressed by diphenyleneiodonium chloride (DPI) pretreatment in the detached leaf segments. This finding suggested the involvement of NADPH oxidase in ABA-induced O2- generation. The esl mutant exhibited significantly higher expression of OsNox2, OsNox5, OsNox6, and OsNox7 in the initial of grain-filling stage, followed by sharply decrease. The transcriptional levels of OsNox1, OsNox3, and OsFR07 in the flag leaf of the esl mutant were significantly lower than those in the wild-type cultivar. The expression levels of OsNox2, OsNox5, OsNox6, and OsNox7 were significantly enhanced by exogenous ABA treatments. The enhanced expression levels of OsNox2 and OsNox6 were dependent on the duration of ABA treatment. The inducible expression levels of OsNox5 and OsNox7 were dependent on ABA concentrations. By contrast, exogenous ABA treatment severely repressed the transcripts of OsNox1, OsNox3, and OsFR07 in the detached leaf segments. Therefore, OsNox2, OsNox5, OsNox6, and OsNox7 were probably involved in the ABA-induced O2- generation in the initial stage of leaf senescence. Subsequently, other oxidases activated in deteriorating cells were associated with ROS generation and accumulation in the

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

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    Tadakatsu Yoneyama

    2016-08-01

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

  2. Oryza sativa (Rice) Hull Extract Inhibits Lipopolysaccharide-Induced Inflammatory Response in RAW264.7 Macrophages by Suppressing Extracellular Signal-regulated Kinase, c-Jun N-terminal Kinase, and Nuclear Factor-κB Activation.

    Science.gov (United States)

    Ha, Sang Keun; Sung, Jeehye; Choi, Inwook; Kim, Yoonsook

    2016-01-01

    Rice ( Oryza sativa ) is a major cereal crop in many Asian countries and an important staple food source. Rice hulls have been reported to possess antioxidant activities. In this study, we evaluated the antiinflammatory effects of rice hull extract and associated signal transduction mechanisms in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. We found that rice hull extract inhibited nitric oxide (NO) and prostaglandin E 2 by suppressing the expression of inducible NO synthase and cyclooxygenase-2, respectively. The release of interleukin-1β and tumor necrosis factor-α was also reduced in a dose-dependent manner. Furthermore, rice hull extract attenuated the activation of nuclear factor-kappa B (NF-κB), as well as the phosphorylation of mitogen-activated protein kinases, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK), in LPS-stimulated RAW264.7 cells. This suggests that rice hull extract decreases the production of inflammatory mediators by downregulating ERK and JNK and the NF-κB signal pathway in RAW 264.7 cells. Rice hull extract inhibits the lipopolysaccharide-induced inflammatory response in RAW264.7 macrophages.Rice hull extract inhibited nitric oxide and prostaglandin E 2 by suppressing the expression of inducible NO synthase and cyclooxygenase-2, respectively.Rice hull extract exerted anti-inflammatory effect through inhibition of nuclear factor-kappa B, extracellular signal-regulated kinase and c-Jun N-terminal kinase signaling pathways.Rice hull extract may provide a potential therapeutic approach for inflammatory diseases. Abbreviations used: COX-2: cyclooxygenase-2, ERK: extracellular signal-regulated kinase, IκB: inhibitory kappa B, IL-1β: interleukin-1β, iNOS: inducible NO synthase, JNK: c-Jun N-terminal kinase, LPS: lipopolysaccharide, MAPKs: mitogen-activated protein kinases, NF-κB: nuclear factor-κB, NO: nitric oxide, PGE2: prostaglandin E2, RHE: rice hull extract, ROS: reactive oxygen species

  3. Evaluación de la concentración de mercurio en arroz (Oryza sativa crudo y cocido procedente del municipio de San Marcos- Sucre y zona aurífera del municipio de Ayapel - Córdoba

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    Marcela P. Argumedo G.

    2015-08-01

    Full Text Available Introducción: Los metales se encuentran en todos los alimentos, siendo de mayor preocupación la presencia de metales tóxicos como el mercurio, debido a los efectos adversos que causa en la salud del hombre, lo que lo ha convertido en un grave problema de salud pública. Objetivo: Evaluar la concentración de mercurio en arroz (Oryza sativa crudo y cocido procedente del municipio de San Marcos - Sucre y zona aurífera del municipio de Ayapel - Córdoba. Metodología: El presente estudio es de tipo exploratorio y experimental. La toma de muestras fue realizada en tiempo de recolección del arroz (septiembre y se tomaron tres repeticiones de cada tipo o variedad de arroz (Fedearroz 2000 - LD 473. La cocción del alimento fue realizada en el laboratorio en condiciones similares a las utilizadas por habitantes de las comunidades donde fueron recolectadas las muestras. Para los análisis de relación estadística entre los tratamientos de cocción y la concentración de mercurio total en muestras, fue realizado un análisis de correlación simple. La determinación de diferencias estadísticamente significativas entre las muestras de arroz crudo y cocido fue realizada mediante un t-test y Anova. Resultados: Se presentaron concentraciones bajas de mercurio total y metilmercurio en las muestras de arroz crudo y cocido. Además, fue detectado que el proceso de cocción del alimento disminuye las concentraciones de HgT, en los diferentes tratamientos de tiempo de cocción. Conclusiones: Los habitantes de los municipios en estudio están expuestos a concentraciones mínimas de mercurio que podrían ser perjudiciales para su salud, debido a la alta ingesta de este cereal en la dieta de las comunidades.

  4. Effect of Feeding High Gamma-Aminobutyric Acid-Containing Giant Embryo Black Sticky Rice (Oryza sativa L.) on Anxiety-Related Behavior of C57BL/6 Mice.

    Science.gov (United States)

    Jung, Woo-Young; Kim, Sung-Gon; Lee, Jin-Seong; Kim, Hyeon-Kyeong; Son, Beung-Gu; Kim, Jong-Woo; Suh, Jae-Won

    2017-08-01

    The aim of this study was to determine the effect of feeding high gamma-aminobutyric acid (GABA)-containing black sticky rice giant embryo (BSRGE, Oryza sativa L.) on anxiety-related behavior of C57BL/6 mice. Experimental feedstuff (BSRGE with high GABA+AIN-76A) and control (AIN-76A) were provided to C57BL/6 mouse for 10 days. Antianxiety effects of BSRGE with high GABA were measured using an elevated plus maze. On day 8, the number of open arm entries by GABA and control groups were 1.10 ± 1.60 (mean ± SD) and 0.00 ± 0.00 (P = .030). On day 10, the number of open arm entries by the GABA group was 2.00 ± 1.89, which was significantly (P = .025) higher than that in the control group (0.40 ± 0.84). On day 8, the time the mice spent in open arm in the GABA group and control group was 3.60 ± 7.06 and 0.00 ± 0.00 sec (P = .068), respectively. On day 10, the time the mice in the GABA and control groups spent in open arm was 6.20 ± 5.35 sec and 1.80 ± 3.82 sec (P = .042), respectively. In repeated analysis of variance for the number of entries into open arm and time spent in open arm, significant differences were found between the two groups. Therefore, BSRGE with high GABA content might have an antianxiety effect. This study can serve as a preliminary study so that further antianxiety effects of BSRGE can be determined in more extended animal or clinical research studies in the future.

  5. Identification of molecular markers linked to rice bacterial blight resistance genes from Oryza meyeriana

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    Jing WANG,Chen CHENG,Yanru ZHOU,Yong YANG,Qiong MEI,Junmin LI,Ye CHENG,Chengqi YAN,Jianping CHEN

    2015-09-01

    Full Text Available Y73 is a progeny of asymmetric somatic hybridization between Oryza sativa cv. Dalixiang and the wild rice species Oryza meyeriana. Inoculation with a range of strains of Xanthomonas oryzae pv. oryzae showed that Y73 had inherited a high level of resistance to rice bacterial blight (BB from its wild parent. An F2 population of 7125 individuals was constructed from the cross between Y73 and a BB-susceptible cultivar IR24. After testing 615 SSR and STS markers covering the 12 rice chromosomes, 186 markers were selected that showed polymorphism between Y73 and IR24. Molecular markers linked to the BB resistance genes in Y73 were scanned using the F2 population and the polymorphic markers. The SSR marker RM128 on chromosome 1, the STS marker R03D159 on chromosome 3 and the STS marker R05D104 on chromosome 5 were found to be linked to the rice BB resistance genes in Y73.

  6. Ectopic expression of a vesicle trafficking gene, OsRab7, from Oryza ...

    African Journals Online (AJOL)

    Jane

    2011-07-18

    Jul 18, 2011 ... OsRab7, from Oryza sativa, confers tolerance to several ... Key Laboratory of Molecular Biology and Gene Engineering, College of Life Science, Nanchang University, ... The reverse transcription was performed using MMLV.

  7. Recent and projected increases in atmospheric CO2 concentration can enhance gene flow between wild and genetically altered rice (Oryza sativa).

    Science.gov (United States)

    Ziska, Lewis H; Gealy, David R; Tomecek, Martha B; Jackson, Aaron K; Black, Howard L

    2012-01-01

    Although recent and projected increases in atmospheric carbon dioxide can alter plant phenological development, these changes have not been quantified in terms of floral outcrossing rates or gene transfer. Could differential phenological development in response to rising CO(2) between genetically modified crops and wild, weedy relatives increase the spread of novel genes, potentially altering evolutionary fitness? Here we show that increasing CO(2) from an early 20(th) century concentration (300 µmol mol(-1)) to current (400 µmol mol(-1)) and projected, mid-21(st) century (600 µmol mol(-1)) values, enhanced the flow of genes from wild, weedy rice to the genetically altered, herbicide resistant, cultivated population, with outcrossing increasing from 0.22% to 0.71% from 300 to 600 µmol mol(-1). The increase in outcrossing and gene transfer was associated with differential increases in plant height, as well as greater tiller and panicle production in the wild, relative to the cultivated population. In addition, increasing CO(2) also resulted in a greater synchronicity in flowering times between the two populations. The observed changes reported here resulted in a subsequent increase in rice dedomestication and a greater number of weedy, herbicide-resistant hybrid progeny. Overall, these data suggest that differential phenological responses to rising atmospheric CO(2) could result in enhanced flow of novel genes and greater success of feral plant species in agroecosystems.

  8. Recent and projected increases in atmospheric CO2 concentration can enhance gene flow between wild and genetically altered rice (Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Lewis H Ziska

    Full Text Available Although recent and projected increases in atmospheric carbon dioxide can alter plant phenological development, these changes have not been quantified in terms of floral outcrossing rates or gene transfer. Could differential phenological development in response to rising CO(2 between genetically modified crops and wild, weedy relatives increase the spread of novel genes, potentially altering evolutionary fitness? Here we show that increasing CO(2 from an early 20(th century concentration (300 µmol mol(-1 to current (400 µmol mol(-1 and projected, mid-21(st century (600 µmol mol(-1 values, enhanced the flow of genes from wild, weedy rice to the genetically altered, herbicide resistant, cultivated population, with outcrossing increasing from 0.22% to 0.71% from 300 to 600 µmol mol(-1. The increase in outcrossing and gene transfer was associated with differential increases in plant height, as well as greater tiller and panicle production in the wild, relative to the cultivated population. In addition, increasing CO(2 also resulted in a greater synchronicity in flowering times between the two populations. The observed changes reported here resulted in a subsequent increase in rice dedomestication and a greater number of weedy, herbicide-resistant hybrid progeny. Overall, these data suggest that differential phenological responses to rising atmospheric CO(2 could result in enhanced flow of novel genes and greater success of feral plant species in agroecosystems.

  9. The biosynthesis, structure and gelatinization properties of starches from wild and cultivated African rice species (Oryza barthii and Oryza glaberrima).

    Science.gov (United States)

    Wang, Kai; Wambugu, Peterson W; Zhang, Bin; Wu, Alex Chi; Henry, Robert J; Gilbert, Robert G

    2015-09-20

    The molecular structure and gelatinization properties of starches from domesticated African rice (Oryza glaberrima) and its wild progenitor (Oryza barthii) are determined and comparison made with Asian domesticated rice (Oryza sativa), the commonest commercial rice. This suggests possible enzymatic processes contributing to the unique traits of the African varieties. These have similar starch structures, including smaller amylose molecules, but larger amounts of amylose chains across the whole amylose chain-length distribution, and higher amylose contents, than O. sativa. They also show a higher proportion of two- and three-lamellae spanning amylopectin branch chains (degree of polymerization 34-100) than O. sativa, which contributes to their higher gelatinization temperatures. Fitting amylopectin chain-length distribution with a biosynthesis-based mathematical model suggests that the reason for this difference might be because O. glaberrima and O. barthii have more active SSIIIa and/or less active SBEIIb enzymes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. 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 (BC 3 F 5 ) 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.

  11. Comparative proteomics and protein profile related to phenolic compounds and antioxidant activity in germinated Oryza sativa 'KDML105' and Thai brown rice 'Mali Daeng' for better nutritional value.

    Science.gov (United States)

    Maksup, Sarunyaporn; Pongpakpian, Sarintip; Roytrakul, Sittiruk; Cha-Um, Suriyan; Supaibulwatana, Kanyaratt

    2018-01-01

    Brown rice (BR) and germinated brown rice (GBR) are considered as prime sources of carbohydrate and bioactive compounds for more than half of the populations worldwide. Several studies have reported on the proteomics of BR and GBR; however, the proteomic profiles related to the synthesis of bioactive compounds are less well documented. In the present study, BR and GBR were used in a comparative analysis of the proteomic and bioactive compound profiles for two famous Thai rice varieties: Khao Dawk Mali 105 (KDML) and Mali Daeng (MD). The proteomes of KDML and MD revealed differences in the expression patterns of proteins after germination. Total phenolic compound content, anthocyanin contents and antioxidant activity of red rice MD was approximately 2.6-, 2.2- and 9.2-fold higher, respectively, compared to that of the white rice KDML. Moreover, GBR of MD showed higher total anthocyanin content and greater antioxidant activity, which is consistent with the increase expression of several proteins involved in the biosynthesis of phenolic compounds and protection against oxidative stress. Red rice MD exhibits higher nutrient values compared to white rice KDML and the appropriate germination of brown rice could represent a method for improving health-related benefits. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  12. Determination of Cadmium and Lead levels in high consumed rice (Oryza Sativa L. cultivated in Lorestan province and its comparison with national standards

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    roshanak Hedayatifar

    2011-03-01

    Full Text Available Rice is the main food of people in Iran and about 2.4 billion of the world population. Although its cultivation areas are less than wheat but 85% of the total product is used by people. Consumption of rice per person is estimated 42.5 kg in Iran. So it is the second high consumed agricultural product. The aim of this study was determination amount of toxic and heavy metals in high consumed rice varites cultivated in different areas of Lorestan province. Materials and Methods: In this study 99 rice samples (Tarem and Domsiah cultivated in three areas of Lorestan( khorramabad, Dorud and Borujerd province were collected. Amount of Lead and Cadmium were analyzed by atomic absorption model BRAIC WFX 130. Data were gathered and analyzed by SPSS software and compared with national standards. Results: The results for Cd and Pb were 0.037±0.06 and 0.077±0.08 mg/kg respectively. Conclusion: Cadmium and Lead levels in rice samples caltivated in Lorestan province were less than Permissible limit, so there is no risk for human health.

  13. Root uptake of 14C leached from the low-level radioactive waste for sub-surface disposal with engineered barriers by Oryza sativa L. (2). Distribution of 14C in rice plant on the case using acetic acid as 14C-source

    International Nuclear Information System (INIS)

    Suzuki, Hiroyuki; Ishii, Nobuyoshi; Tagami, Keiko; Uchida, Shigeo

    2012-01-01

    The behavior of 14 C from radioactive waste in paddy rice (Oryza sativa L.) at different stages of plant development was studied using the hydroponic and acetic acid as 14 C-source. For 14 C-application, plant root was soaked for 2 hours in a nutrient solution containing 14 C-acetic acid at the vegetative growth stage (Aug. 2, 2007), heading (flowering) stage (Aug. 30, 2007) and milk-ripe stage (Sep. 13, 2007). In final sampling day (Mar. 5, 2008), 0.88 - 1.96% of the applied radioactivity was recovered from whole plant, however, the ratio of recovered radioactivity was not different at the growth stage. The distribution of 14 C absorbed at each stage to each organ was noted to be highest in the submersed root through all the stages. Therefore the mixing of the root residue at the time of plowing would result in enhancement of the soil persistence of 14 C. (author)

  14. A putative gene sbe3-rs for resistant starch mutated from SBE3 for starch branching enzyme in rice (Oryza sativa L..

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    Ruifang Yang

    Full Text Available Foods high in resistant starch (RS are beneficial to prevent various diseases including diabetes, colon cancers, diarrhea and chronic renal or hepatic diseases. Elevated RS in rice is important for public health since rice is a staple food for half of the world population. A japonica mutant 'Jiangtangdao 1' (RS = 11.67% was crossed with an indica cultivar 'Miyang 23' (RS = 0.41%. The mutant sbe3-rs that explained 60.4% of RS variation was mapped between RM6611 and RM13366 on chromosome 2 (LOD = 36 using 178 F(2 plants genotyped with 106 genome-wide polymorphic SSR markers. Using 656 plants from four F(3:4 families, sbe3-rs was fine mapped to a 573.3 Kb region between InDel 2 and InDel 6 using one STS, five SSRs and seven InDel markers. SBE3 which codes for starch branching enzyme was identified as a candidate gene within the putative region. Nine pairs of primers covering 22 exons were designed to sequence genomic DNA of the wild type for SBE3 and the mutant for sbe3-rs comparatively. Sequence analysis identified a missense mutation site where Leu-599 of the wild was changed to Pro-599 of the mutant in the SBE3 coding region. Because the point mutation resulted in the loss of a restriction enzyme site, sbe3-rs was not digested by a CAPS marker for SpeI site while SBE3 was. Co-segregation of the digestion pattern with RS content among 178 F(2 plants further supported sbe3-rs responsible for RS in rice. As a result, the CAPS marker could be used in marker-assisted breeding to develop rice cultivars with elevated RS which is otherwise difficult to accurately assess in crops. Transgenic technology should be employed for a definitive conclusion of the sbe3-rs.

  15. Response of the leaf photosynthetic rate to available nitrogen in erect panicle-type rice (Oryza sativa L. cultivar, Shennong265

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    Chihiro Urairi

    2016-07-01

    Full Text Available Increasing the yield of rice per unit area is important because of the demand from the growing human population in Asia. A group of varieties called erect panicle-type rice (EP achieves very high yields under conditions of high nitrogen availability. Little is known, however, regarding the leaf photosynthetic capacity of EP, which may be one of the physiological causes of high yield. We analyzed the factors contributing to leaf photosynthetic rate (Pn and leaf mesophyll anatomy of Nipponbare, Takanari, and Shennong265 (a EP type rice cultivar varieties subjected to different nitrogen treatments. In the field experiment, Pn of Shennong265 was 33.8 μmol m−2 s−1 in the high-N treatment, and was higher than that of the other two cultivars because of its high leaf nitrogen content (LNC and a large number of mesophyll cells between the small vascular bundles per unit length. In Takanari, the relatively high value of Pn (31.5 μmol m−2 s−1 was caused by the high stomatal conductance (gs; .72 mol m−2 s−1 in the high-N treatment. In the pot experiment, the ratio of Pn/Ci to LNC, which may reflect mesophyll conductance (gm, was 20–30% higher in Nipponbare than in Takanari or Shennong265 in the high N availability treatment. The photosynthetic performance of Shennong265 might be improved by introducing the greater ratio of Pn/Ci to LNC found in Nipponbare and greater stomatal conductance found in Takanari.

  16. Herencia de la resistencia al daño mecánico causado por Tagosodes orizicolus (Muir (Homoptera-Delphacidae en arroz Oryza sativa

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    Cuevas P. Federico

    1996-12-01

    Full Text Available

    In Colombia all rice varieties developed are reported as resistant to Tagosodes orizicolus. Given the narrow genetic base of the resistant sources, this study was undertaken to identify the resistant parents or donors more oftenly used in Latin America. The materials were characterized as resistant (Mudgo, Amistad 82, IRAT 120, IRAT 124, Makalioka or susceptible based on the free chosen test and non chosen test and on the survival and oviposition of the insect (Chianan 8, Colombia 1, Bluebonnet 50, IR 8 (lCA, IR 8 (IRRI, Tetep and Cica 8. The damage was associated with insect survival, oviposition and eggs eclotion. To determine heritability two parents (Makalioka and Mudgo, were crossed with IR 8 F1 and F3 populations were also evaluated based on the free chosen test.

     

     

    En Colombia las variedades de arroz desarrolladas se consideran como resistentes a Tagosodes orizicolus. Dada la estrechez genética de las fuentes de resistencia, se inició este estudio para identificar los progenitores donantes de resistencia usados con mayor frecuencia en América Latina. Los materiales se caracterizaron como resistentes (Mudgo, Amistad 82, IRAT, 120, IRAT 124 Y Makalioka o susceptibles (Chianan 8, Colombia 1, Bluebonnet 50, IR 8 (lCA, IR (IRRI, Tetep y Cica 8, con base en las pruebas de libre escogencia, no escogencia, sobre vivencia y oviposición. El daño estuvo asociado con la supervivencia, oviposición y eclosión de huevos del insecto. Para la determinación de la herencia se cruzaron los progenitores Makalioka y Mudgo con IR8. En la Progenie F1 del cruzamiento resistente x resistente el 111% de las plantas fueron susceptibles; Mudgo y Makalioka segregaron 23 y 41% de plantas susceptibles.

  17. Combining QTL mapping and transcriptome profiling of bulked RILs for identification of functional polymorphism for salt tolerance genes in rice (Oryza sativa L.).

    Science.gov (United States)

    Pandit, Awadhesh; Rai, Vandna; Bal, Subhashis; Sinha, Shikha; Kumar, Vinod; Chauhan, Mahesh; Gautam, Raj K; Singh, Rakesh; Sharma, Prakash C; Singh, Ashok K; Gaikwad, Kishor; Sharma, Tilak R; Mohapatra, Trilochan; Singh, Nagendra K

    2010-08-01

    Identification of genes for quantitative traits is difficult using any single approach due to complex inheritance of the traits and limited resolving power of the individual techniques. Here a combination of genetic mapping and bulked transcriptome profiling was used to narrow down the number of differentially expressed salt-responsive genes in rice in order to identify functional polymorphism of genes underlying the quantitative trait loci (QTL). A population of recombinant inbred lines (RILs) derived from cross between salt-tolerant variety CSR 27 and salt-sensitive variety MI 48 was used to map QTL for salt ion concentrations in different tissues and salt stress susceptibility index (SSI) for spikelet fertility, grain weight, and grain yield. Eight significant QTL intervals were mapped on chromosomes 1, 8, and 12 for the salt ion concentrations and a QTL controlling SSI for spikelet fertility was co-located in one of these intervals on chromosome 8. However, there were total 2,681 genes in these QTL intervals, making it difficult to pinpoint the genes responsible for the functional differences for the traits. Similarly, transcriptome profiling of the seedlings of tolerant and sensitive parents grown under control and salt-stress conditions showed 798 and 2,407 differentially expressed gene probes, respectively. By analyzing pools of RNA extracted from ten each of extremely tolerant and extremely sensitive RILs to normalize the background noise, the number of differentially expressed genes under salt stress was drastically reduced to 30 only. Two of these genes, an integral transmembrane protein DUF6 and a cation chloride cotransporter, were not only co-located in the QTL intervals but also showed the expected distortion of allele frequencies in the extreme tolerant and sensitive RILs, and therefore are suitable for future validation studies and development of functional markers for salt tolerance in rice to facilitate marker-assisted breeding.

  18. Characterisation of a novel quantitative trait locus, GN4-1, for grain number and yield in rice (Oryza sativa L.).

    Science.gov (United States)

    Zhou, Yong; Tao, Yajun; Yuan, Yuan; Zhang, Yanzhou; Miao, Jun; Zhang, Ron; Yi, Chuandeng; Gong, Zhiyun; Yang, Zefeng; Liang, Guohua

    2018-03-01

    A novel QTL for grain number, GN4-1, was identified and fine-mapped to an ~ 190-kb region on the long arm of rice chromosome 4. Rice grain yield is primarily determined by three components: number of panicles per plant, grain number per panicle and grain weight. Among these traits, grain number per panicle is the major contributor to grain yield formation and is a crucial trait for yield improvement. In this study, we identified a major quantitative trait locus (QTL) responsible for rice grain number on chromosome 4, designated GN4-1 (a QTL for Grain Number on chromosome 4), using advanced segregating populations derived from the crosses between an elite indica cultivar 'Zhonghui 8006' (ZH8006) and a japonica rice 'Wuyunjing 8' (WYJ8). GN4-1 was delimited to an ~ 190-kb region on chromosome 4. The genetic effect of GN4-1 was estimated using a pair of near-isogenic lines. The GN4-1 gene from WYJ8 promoted accumulation of cytokinins in the inflorescence and increased grain number per panicle by ~ 17%. More importantly, introduction of the WYJ8 GN4-1 gene into ZH8006 increased grain yield by ~ 14.3 and ~ 11.5% in the experimental plots in 2014 and 2015, respectively. In addition, GN4-1 promoted thickening of the culm and may enhance resistance to lodging. These results demonstrate that GN4-1 is a potentially valuable gene for improvement of yield and lodging resistance in rice breeding.

  19. Heavy metals (lead, cadmium, methylmercury, arsenic) in commonly imported rice grains (Oryza sativa) sold in Saudi Arabia and their potential health risk.

    Science.gov (United States)

    Al-Saleh, Iman; Abduljabbar, Mai

    2017-10-01

    rice, with total arsenic the major contributor followed by methylmercury. CR for total arsenic, whether consuming soaked, rinsed, un-soaked or unrinsed grains, exceeded the acceptable level of 10 -4 . Long-term consumption of rice contaminated with heavy metals, particularly arsenic, can pose potential health risks to the local population, especially vulnerable groups (pregnant women, children, elderly and patients). More attention should thus be given to contaminated rice and preventive measures should be taken. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Genomic affinity between Oryza sativa and Oryza brachyantha as ...

    African Journals Online (AJOL)

    USER

    2010-05-24

    May 24, 2010 ... distantly related wild species, usually difficult to produce. These hybrids are ... assessment of genomic relationship between these two species by .... closely related and the sterility of the hybrid may be due to genetics and not ...

  1. Effect of dietary supplementation with Rhizopus oryzae or Chrysonilia crassa on growth performance, blood profile, intestinal microbial population, and carcass traits in broilers exposed to heat stress

    OpenAIRE

    S. Sugiharto; T. Yudiarti; I. Isroli; E. Widiastuti; F. D. Putra

    2017-01-01

    Dietary supplementation of additives has recently been part of strategies to deal with the detrimental effects of heat stress (HS) on the performance and carcass traits in broiler chicks. This study aimed to investigate the effect of dietary supplementation with the fungi Rhizopus oryzae or Chrysonilia crassa on growth, blood profile, intestinal microbial population and carcass traits in broiler chicks subjected to HS. R. oryzae and C. crassa are filamentous fungi isolated from...

  2. WATER DEFICIT EFFECT ON YIELD AND FORAGE QUALITY OF MEDICAGO SATIVA POPULATIONS UNDER FIELD CONDITIONS IN MARRAKESH AREA (MOROCCO

    Directory of Open Access Journals (Sweden)

    Mohamed FARISSI

    2014-06-01

    Full Text Available The present study focused the effect of water deficit on agronomic potential and some traits related to forage quality in plants of Moroccan Alfalfa (Medicago sativa L. populations (Taf 1, Taf 2, Dem and Tata originated from Oasis and High Atlas of Morocco and an introduced variety from Australia (Siriver. The experiment was conducted under field conditions in experimental station of INRA-Marrakech and under two irrigation treatments. The first treatment was normal irrigation, providing an amount of water corresponding to the potential evapo-transpiration of the crop, and the second treatment was water deficit stress (one irrigation per cut. For each treatment, the experiment was conducted as a split plot based on a randomized complete block design with four replications. The plants were measured and analyzed over three cuts. Some agronomic traits as, plant height, fresh and dry forage yields were measured. The forage quality was evaluated by leaf:stem ratio and the contents of plants in proteins and nitrogen. The results indicated that the water deficit has negatively affected the plant height and forage yield. The decrease in leaf:stem ratio was observed under water deficit conditions. However, the proteins and nitrogen contents were unaffected. The behavior of tested alfalfa genotypes was significantly different. The Moroccan alfalfa populations were more adapted to water deficit conditions comparatively to Siriver variety and the Tata population was the most adapted one.

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

    Science.gov (United States)

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

    2017-12-01

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

  4. High Levels of Phytophenolics and Antioxidant Activities in Oryza ...

    African Journals Online (AJOL)

    Purpose: To investigate phenolic levels, phytophenolic profiles and total antioxidant activities of Oryza sativa, unpolished Thai rice. Methods: Unpolished Thai rice strains of Leum Phua, Klam, Hawm Nil and Black Rose were measured for antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), ...

  5. Population genomics identifies the origin and signatures of selection of Korean weedy rice

    OpenAIRE

    He, Qiang; Kim, Kyu?Won; Park, Yong?Jin

    2016-01-01

    Summary Weedy rice is the same biological species as cultivated rice (Oryza sativa); it is also a noxious weed infesting rice fields worldwide. Its formation and population?selective or ?adaptive signatures are poorly understood. In this study, we investigated the phylogenetics, population structure and signatures of selection of Korean weedy rice by determining the whole genomes of 30 weedy rice, 30 landrace rice and ten wild rice samples. The phylogenetic tree and results of ancestry infere...

  6. Xanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis

    Directory of Open Access Journals (Sweden)

    Abdjad Asih Nawangsih

    2011-04-01

    Full Text Available Xanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis. X. oryzae pv. oryzae (Xoo causes bacterial leaf blight (BLB of rice (Oryza sativa L., a major disease that constrains production of the staple crop in many countries of the world. Identification of X. oryzae pv. oryzae (Xoo was conducted based on the disease symptoms, pathogenicity, morphological, physiological, and genetic characteristics of bacterial cultures isolated from the infected plants. Fifty bacterial isolates predicted as Xoo have been successfully isolated. They are aerobic, rod shaped, and Gram negative bacteria. The isolates were evaluated for their hypersensitivity in tobacco and pathogenicity in rice plant. Fifty isolates induced hypersensitive reaction in tobacco and showed pathogenicity symptom in rice in different length. Based on physiological test, hypersensitivity and pathogenicity reactions, three bacterial isolates strongly predicted as Xoo, i.e. STG21, STG42, and STG46, were non indole formation, non pigment fluorescent, hydrolyzed casein, catalase activity positive, but negative oxidase. Partial sequencing of 16S rRNA genes of STG21 and STG42 showed 80% and 82% homology with X. oryzae, respectively, while STG46 showed 84% homology with X. campestris. Mini-Tn5 transposon mutagenesis of STG21 generated one of the mutants (M5 lossed it’s ability to induce hypersensitive reaction in tobacco plant and deficient in pathogenicity on rice. The lesion length of rice leaf caused by the mutant M5 decreased up to 80%.

  7. Níveis de dano econômico para decisão de controle de capim-arroz (Echinochloa spp. em arroz irrigado (Oryza sativa Economic threshold level for barnyardgrass (Echinochloa spp. control decision in flooded rice (Oryza sativa

    Directory of Open Access Journals (Sweden)

    L. Galon

    2007-12-01

    barnyardgrass populations, rice varieties and flooding timings. Thus, two trials were carried out using a completely randomized design with no replications. The first trial treatments consisted of six rice varieties: BRS-Atalanta, IRGA 421 (very short cycle; IRGA 416, IRGA 417, Avaxi (short cycle and BRS-Fronteira (medium cycle; as well as ten barnyardgrass populations. The second trial treatments were flooding timings: 1, 10 and 20 DAT (days after herbicide treatment and barnyardgrass populations. The estimated EWT for barnyardgrass varied in function of the adopted management practices in the flooded rice crop. The estimated EWT for rice IRGA 416 and 417 was greater than that of the other cultivars when in barnyardgrass competition. Flooding timing delay reduced EWT for the BRS-Pelota rice variety. Increased potential yield losses, product value and herbicide efficiency as well as reduced control price reduced EWT, rendering viable the adoption of management practices at low barnyardgrass density when competing with flooded rice.

  8. Bacterial population dynamics during the ensiling of Medicago sativa (alfalfa) and subsequent exposure to air.

    Science.gov (United States)

    McGarvey, J A; Franco, R B; Palumbo, J D; Hnasko, R; Stanker, L; Mitloehner, F M

    2013-06-01

    To describe, at high resolution, the bacterial population dynamics and chemical transformations during the ensiling of alfalfa and subsequent exposure to air. Samples of alfalfa, ensiled alfalfa and silage exposed to air were collected and their bacterial population structures compared using 16S rRNA gene libraries containing approximately 1900 sequences each. Cultural and chemical analyses were also performed to complement the 16S gene sequence data. Sequence analysis revealed significant differences (P alfalfa-derived library contained mostly sequences associated with the Gammaproteobacteria (including the genera: Enterobacter, Erwinia and Pantoea); the ensiled material contained mostly sequences associated with the lactic acid bacteria (LAB) (including the genera: Lactobacillus, Pediococcus and Lactococcus). Exposure to air resulted in even greater percentages of LAB, especially among the genus Lactobacillus, and a significant drop in bacterial diversity. In-depth 16S rRNA gene sequence analysis revealed significant bacterial population structure changes during ensiling and again during exposure to air. This in-depth description of the bacterial population dynamics that occurred during ensiling and simulated feed out expands our knowledge of these processes. © 2013 The Society for Applied Microbiology No claim to US Government works.

  9. Desempenho de populações híbridas F2 de arroz-vermelho (Oryza sativa) com arroz transgênico (O. sativa) resistente ao herbicida amonio-glufosinate Performance of F2 hybrid populations of red rice (Oryza sativa) with ammonium-glufosinate-resistant transgenic rice (O. sativa)

    OpenAIRE

    J.A. Noldin; S. Yokoyama; H. Stuker; F.T. Rampelotti; M.I.F. Gonçalves; D.S. Eberhardt; A. Abreu; P. Antunes; J. Vieira

    2004-01-01

    O arroz-vermelho e o arroz-preto constituem-se nas principais plantas daninhas infestantes da cultura de arroz irrigado, devido à dificuldade de controle seletivo desta espécie em lavouras comerciais. A utilização de cultivares geneticamente modificados resistentes a herbicidas não-seletivos constitui uma alternativa de controle do arroz-vermelho e arroz-preto em arroz irrigado. O objetivo deste trabalho foi avaliar o comportamento de populações híbridas F2 originárias do cruzamento entre o a...

  10. Assessment of heavy metals (Cd and Pb) and micronutrients (Cu, Mn, and Zn) of paddy (Oryza sativa L.) field surface soil and water in a predominantly paddy-cultivated area at Puducherry (Pondicherry, India), and effects of the agricultural runoff on the elemental concentrations of a receiving rivulet.

    Science.gov (United States)

    Reddy, M Vikram; Satpathy, Deepmala; Dhiviya, K Shyamala

    2013-08-01

    The concentrations of toxic heavy metals-Cd and Pb and micronutrients-Cu, Mn, and Zn were assessed in the surface soil and water of three different stages of paddy (Oryza sativa L.) fields, the stage I-the first stage in the field soon after transplantation of the paddy seedlings, holding adequate amount of water on soil surface, stage II-the middle stage with paddy plants of stem of about 40 cm length, with sufficient amount of water on the soil surface, and stage III-the final stage with fully grown rice plants and very little amount of water in the field at Bahour, a predominantly paddy cultivating area in Puducherry located on the southeast Coast of India. Comparison of the heavy metal and micronutrient concentrations of the soil and water across the three stages of paddy field showed their concentrations were significantly higher in soil compared with that of water (p soil. The elemental concentrations in paddy soil as well as water was in the ranking order of Cd > Mn > Zn > Cu > Pb indicating concentration of Cd was maximum and Pb was minimum. The elemental concentrations in both soil and water across the three stages showed a ranking order of stage II > stage III > stage I. The runoff from the paddy fields has affected the elemental concentrations of the water and sediment of an adjacent receiving rivulet.

  11. Identification of heterotic loci associated with yield-related traits in Chinese common wild rice (Oryza rufipogon Griff.).

    Science.gov (United States)

    Luo, Xiaojin; Wu, Shuang; Tian, Feng; Xin, Xiaoyun; Zha, Xiaojun; Dong, Xianxin; Fu, Yongcai; Wang, Xiangkun; Yang, Jinshui; Sun, Chuanqing

    2011-07-01

    Many rice breeding programs have currently reached yield plateaus as a result of limited genetic variability in parental strains. Dongxiang common wild rice (Oryza rufipogon Griff.) is the progenitor of cultivated rice (Oryza sativa L.) and serves as an important gene pool for the genetic improvement of rice cultivars. In this study, heterotic loci (HLs) associated with six yield-related traits were identified in wild and cultivated rice and investigated using a set of 265 introgression lines (ILs) of O. rufipogon Griff. in the background of the Indica high-yielding cultivar Guichao 2 (O. sativa L.). Forty-two HLs were detected by a single point analysis of mid-parent heterosis values from test cross F(1) offspring, and 30 (71.5%) of these HLs showed significantly positive effects, consistent with the superiority shown by the F(1) test cross population in the six yield-related traits under study. Genetic mapping of hsp11, a locus responsible for the number of spikelets per panicle, confirmed the utility of these HLs. The results indicate that favorable HLs capable of improving agronomic traits are available. The identification of HLs between wild rice and cultivated rice could lead to a new strategy for the application of heterosis in rice breeding. Copyright © 2011. Published by Elsevier Ireland Ltd.

  12. Effect of lead on nucleic acid and protein contents of rice (Oryza sativa L. ) seedlings and its interaction with IAA and GA/sub 3/ in different plant systems

    Energy Technology Data Exchange (ETDEWEB)

    Maitra, P.; Mukherh, S.

    1979-09-01

    Activity of lead acetate, (CH/sub 3/COO)/sub 2/Pb, 3 H/sub 2/O, was studied in germinating rice seedlings with respect to RNA, DNA and alkali soluble protein contents. RNA, DNA and protein contents greatly reduced both in embryo and endosperm with increasing concentrations of lead and with concomitant increase in amino acid content in embryo. When IAA was supplied in combination with lead acetate, variable amounts of relief of elongation inhibition of wheat coleoptile sections were noticed. With GA/sub 3/, however, lead-induced inhibition of either lettuce (Lactuca sativa L.) hypocotyl elongation or ..cap alpha..-amylase production in rice half seeds was largely overcome.

  13. Transposable element distribution, abundance and role in genome size variation in the genus Oryza.

    Science.gov (United States)

    Zuccolo, Andrea; Sebastian, Aswathy; Talag, Jayson; Yu, Yeisoo; Kim, HyeRan; Collura, Kristi; Kudrna, Dave; Wing, Rod A

    2007-08-29

    The genus Oryza is composed of 10 distinct genome types, 6 diploid and 4 polyploid, and includes the world's most important food crop - rice (Oryza sativa [AA]). Genome size variation in the Oryza is more than 3-fold and ranges from 357 Mbp in Oryza glaberrima [AA] to 1283 Mbp in the polyploid Oryza ridleyi [HHJJ]. Because repetitive elements are known to play a significant role in genome size variation, we constructed random sheared small insert genomic libraries from 12 representative Oryza species and conducted a comprehensive study of the repetitive element composition, distribution and phylogeny in this genus. Particular attention was paid to the role played by the most important classes of transposable elements (Long Terminal Repeats Retrotransposons, Long interspersed Nuclear Elements, helitrons, DNA transposable elements) in shaping these genomes and in their contributing to genome size variation. We identified the elements primarily responsible for the most strikingly genome size variation in Oryza. We demonstrated how Long Terminal Repeat retrotransposons belonging to the same families have proliferated to very different extents in various species. We also showed that the pool of Long Terminal Repeat Retrotransposons is substantially conserved and ubiquitous throughout the Oryza and so its origin is ancient and its existence predates the speciation events that originated the genus. Finally we described the peculiar behavior of repeats in the species Oryza coarctata [HHKK] whose placement in the Oryza genus is controversial. Long Terminal Repeat retrotransposons are the major component of the Oryza genomes analyzed and, along with polyploidization, are the most important contributors to the genome size variation across the Oryza genus. Two families of Ty3-gypsy elements (RIRE2 and Atlantys) account for a significant portion of the genome size variations present in the Oryza genus.

  14. Selective toxin effects on faster and slower growing individuals in the formation of hormesis at the population level - A case study with Lactuca sativa and PCIB.

    Science.gov (United States)

    Belz, Regina G; Sinkkonen, Aki

    2016-10-01

    Natural plant populations have large phenotypic plasticity that enhances acclimation to local stress factors such as toxin exposures. While consequences of high toxin exposures are well addressed, effects of low-dose toxin exposures on plant populations are seldom investigated. In particular, the importance of 'selective low-dose toxicity' and hormesis, i.e. stimulatory effects, has not been studied simultaneously. Since selective toxicity can change the size distribution of populations, we assumed that hormesis alters the size distribution at the population level, and investigated whether and how these two low-dose phenomena coexist. The study was conducted with Lactuca sativa L. exposed to the auxin-inhibitor 2-(p-chlorophenoxy)-2-methylpropionic acid (PCIB) in vitro. In two separate experiments, L. sativa was exposed to 12 PCIB doses in 24 replicates (50 plants/replicate). Shoot/root growth responses at the population level were compared to the fast-growing (≥90% percentile) and the slow-growing subpopulations (≤10% percentile) by Mann-Whitney U testing and dose-response modelling. In the formation of pronounced PCIB hormesis at the population level, low-dose effects proved selective, but widely stimulatory which seems to counteract low-dose selective toxicity. The selectivity of hormesis was dose- and growth rate-dependent. Stimulation occurred at lower concentrations and stimulation percentage was higher among slow-growing individuals, but partly or entirely masked at the population level by moderate or negligible stimulation among the faster growing individuals. We conclude that the hormetic effect up to the maximum stimulation may be primarily facilitated by an increase in size of the most slow-growing individuals, while thereafter it seems that mainly the fast-growing individuals contributed to the observed hormesis at the population level. As size distribution within a population is related to survival, our study hints that selective effects on slow

  15. Nuclear and original DNA application in Oryza taxonomy and phylogeny

    International Nuclear Information System (INIS)

    Romero, Gabriel O.

    1998-01-01

    Conventional taxonomy and phylogeny of germplasm are based on the tedious characterization of morphological variation. The ability to assay DNA variation that underlies morphological variation offers great promise as a convenient alternative for the genetic characterization of germplasm. Restriction fragment length polymorphism (RFLP) was used to survey DNA variation in 22 species of the genus Oryza. At the ribosomal DNA (rDNA) multigene family, 15 rDNA spacer length (sl) variants were identified using restriction enzyme Sst1 and wheatrDNA unit as probe. Particular sl variants predominated in certain isozyme groups of O. sativa, indicating a potential of sl ploymorphism in varietal classification. The distribution of sl variants supports the origin of O. sativa and O. nivara from O. rufipogon, and that O. spontanea arose from introgressions among O. sativa, O. nivara, and O. rufipogon. The distribution also suggests that the CCgenome, of all the genomes in the Officinalis complex, may be closest to the Sativa complex genomes, and it affirms the genetic position of the Officinalis complex intermediate between the Sativa and Ridleyi complexes. Variation at the Oryza organelle genomes was probed with a maize mitochondrial gene, atpA, a wheat chloroplast inverted repeat segment, p6. Results indicated that the complexes can be differentiated by their mitochondrial genome, but not their chloroplast genome when digested by Sst1 or BamH1. Therefore, the natural DNA variation in the nuclear and mitochondrial genomes has demonstrated great potential in complementing the conventional basis of taxa classification and phylogeny in the genus Oryza. (Author)

  16. Association Analysis of Arsenic-Induced Straighthead in Rice (Oryza sativa L.) Based on the Selected Population with a Modified Model.

    Science.gov (United States)

    Li, Xiaobai; Hu, Biaolin; Pan, Xuhao; Zhang, Ning; Wu, Dianxing

    2017-01-01

    A rice physiological disorder makes mature panicle keep erect with empty grains termed as "straighthead." Straighthead causes yield losses and is a serious threat to rice production worldwide. Here, a new study of association mapping was conducted to identify QTL involved in straighthead. A subset of 380 accessions was selected from the USDA rice core collection and genotyped with 72 genome-wide SSR markers. An optimal model implemented with principle components (PCs) was used in this association mapping. As a result, five markers were identified to be significantly associated with straighthead. Three of them, RM263, RM169, and RM224, were consistent with a previous study. Three markers, RM475, RM263, and RM19, had a resistant allele associated with a decrease in straighthead rating (straighthead rating ≤ 4.8). In contrast, the two other marker loci RM169 and RM224 had a few susceptible alleles associated with an increase in straighthead rating (straighthead rating ≥ 8.7). Interestingly, RM475 is close to QTL " qSH-2 " and " AsS " with straighthead resistance, which was reported in two studies on linkage mapping of straighthead. This finding adds to previous work and is useful for further genetic study of straighthead.

  17. Caracterização agromorfológica interpopulacional em Oryza glumaepatula Interpopulational agro-morphological haracterization of Oryza glumaepatula

    Directory of Open Access Journals (Sweden)

    Mariana Silva Rosa

    2006-01-01

    Full Text Available O gênero Oryza apresenta duas espécies cultivadas e 21 espécies silvestres, sendo quatro originárias da América do Sul e Central. Dentre essas, a única espécie diplóide é Oryza glumaepatula Steud., compatível em cruzamentos com a espécie cultivada O. sativa L. O objetivo deste trabalho foi caracterizar, por meio de caracteres agromorfológicos, oito populações de O. glumaepatula, coletadas em diferentes bacias hidrográficas brasileiras. O experimento foi realizado em casa de vegetação utilizando-se o delineamento em blocos ao acaso com oito tratamentos e seis repetições. Cada parcela foi constituída de quatro plantas, obtendo-se o total de 24 plantas por população. Foram avaliadas três características agronômicas e 18 características morfológicas. Os dados foram analisados utilizando-se estatísticas univariadas e multivariadas. Os resultados mostraram diferenças significativas entre populações para todos os caracteres avaliados, o que indica a grande variabilidade genética observada para todas as populações. Os resultados da análise de componentes principais foram similares aos da análise de agrupamento que classificou as populações em quatro grupos, sendo um grupo para cinco populações da Amazônia, um grupo para uma população do Rio Negro, e dois grupos, um para cada população originária do Rio Xingu e do Rio Paraguai, no Pantanal. A população com características agronômicas mais desejáveis, maior produção de sementes e maior número de perfilhos foi a PG-4, originária do Pantanal Matogrossense, seguida da população JA-4, do Rio Japurá.The genus Oryza contains two cultivated and 21 wild species, and four of these wild species originated from South and Central America. Among these, the only diploid species, compatible in crossing experiments with the cultivated O. sativa L. is O. glumaepatula Steud. The objective of this research was to characterize with morpho-agronomic traits eight

  18. Effects of Aspergillus Oryzae Culture and 2-Hydroxy-4-(Methylthio)-Butanoic Acid on In vitro Rumen Fermentation and Microbial Populations between Different Roughage Sources.

    Science.gov (United States)

    Sun, H; Wu, Y M; Wang, Y M; Liu, J X; Myung, K H

    2014-09-01

    An in vitro experiment was conducted to evaluate the effects of Aspergillus oryzae culture (AOC) and 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on rumen fermentation and microbial populations between different roughage sources. Two roughage sources (Chinese wild rye [CWR] vs corn silage [CS]) were assigned in a 2×3 factorial arrangement with HMB (0 or 15 mg) and AOC (0, 3, or 6 mg). Gas production (GP), microbial protein (MCP) and total volatile fatty acid (VFA) were increased in response to addition of HMB and AOC (p<0.01) for the two roughages. The HMB and AOC showed inconsistent effects on ammonia-N with different substrates. For CWR, neither HMB nor AOC had significant effect on molar proportion of individual VFA. For CS, acetate was increased (p = 0.02) and butyrate was decreased (p<0.01) by adding HMB and AOC. Increase of propionate was only occurred with AOC (p<0.01). Populations of protozoa (p≤0.03) and fungi (p≤0.02) of CWR were differently influenced by HMB and AOC. Percentages of F. succinogenes, R. albus, and R. flavefaciens (p<0.01) increased when AOC was added to CWR. For CS, HMB decreased the protozoa population (p = 0.01) and increased the populations of F. succinogenes and R. albus (p≤0.03). Populations of fungi, F. succinogenes (p = 0.02) and R. flavefacien (p = 0.03) were increased by adding AOC. The HMB×AOC interactions were noted in MCP, fungi and R. flavefacien for CWR and GP, ammonia-N, MCP, total VFA, propionate, acetate/propionate (A/P) and R. albus for CS. It is inferred that addition of HMB and AOC could influence rumen fermentation of forages by increasing the number of rumen microbes.

  19. Genomic diversity and introgression in O. sativa reveal the impact of domestication and breeding on the rice genome.

    Directory of Open Access Journals (Sweden)

    Keyan Zhao

    2010-05-01

    Full Text Available The domestication of Asian rice (Oryza sativa was a complex process punctuated by episodes of introgressive hybridization among and between subpopulations. Deep genetic divergence between the two main varietal groups (Indica and Japonica suggests domestication from at least two distinct wild populations. However, genetic uniformity surrounding key domestication genes across divergent subpopulations suggests cultural exchange of genetic material among ancient farmers.In this study, we utilize a novel 1,536 SNP panel genotyped across 395 diverse accessions of O. sativa to study genome-wide patterns of polymorphism, to characterize population structure, and to infer the introgression history of domesticated Asian rice. Our population structure analyses support the existence of five major subpopulations (indica, aus, tropical japonica, temperate japonica and GroupV consistent with previous analyses. Our introgression analysis shows that most accessions exhibit some degree of admixture, with many individuals within a population sharing the same introgressed segment due to artificial selection. Admixture mapping and association analysis of amylose content and grain length illustrate the potential for dissecting the genetic basis of complex traits in domesticated plant populations.Genes in these regions control a myriad of traits including plant stature, blast resistance, and amylose content. These analyses highlight the power of population genomics in agricultural systems to identify functionally important regions of the genome and to decipher the role of human-directed breeding in refashioning the genomes of a domesticated species.

  20. Effect of dietary supplementation with Rhizopus oryzae or Chrysonilia crassa on growth performance, blood profile, intestinal microbial population, and carcass traits in broilers exposed to heat stress

    Directory of Open Access Journals (Sweden)

    S. Sugiharto

    2017-09-01

    Full Text Available Dietary supplementation of additives has recently been part of strategies to deal with the detrimental effects of heat stress (HS on the performance and carcass traits in broiler chicks. This study aimed to investigate the effect of dietary supplementation with the fungi Rhizopus oryzae or Chrysonilia crassa on growth, blood profile, intestinal microbial population and carcass traits in broiler chicks subjected to HS. R. oryzae and C. crassa are filamentous fungi isolated from the ileum of indigenous Indonesian chickens which exhibited probiotic and antioxidant properties. Two hundred and forty 21-day-old male broiler chicks were randomly allotted into six groups, including birds reared under normal temperature (28 ± 2 °C (CONT, birds reared under HS conditions (35 ± 2 °C (HS-CONT, birds reared under HS and provided with commercial anti-stress formula (HS-VIT, birds reared under HS and provided with R. oryzae (HS-RO, birds reared under HS and provided with C. crassa (HS-CC and birds reared under HS and provided with rice bran (HS-RB. Body weight gain was highest (P < 0. 01 and lowest (P < 0. 01 in CONT and HS-CONT birds, respectively. The heart was heavier (P < 0. 05 in CONT than in HS-CONT and HS-VIT birds. CONT birds had heavier duodenum (P < 0. 05 and jejunum (P < 0. 01 than other birds. Eosinophils was higher (P < 0. 05 in HS-CC than in other birds. Low-density lipoprotein (LDL was higher (P < 0. 05 in HS-CONT than in CONT, HS-VIT and HS-CC birds. Total triglyceride was highest (P < 0. 05 and lowest (P < 0. 05 in HS-RB and HS-RO birds, respectively. Alanine aminotransferase (ALT was higher (P < 0. 05 in HS-CONT than in other HS birds. Total protein was lowest and highest (P < 0. 05 in CONT and HS-CONT birds, respectively. Albumin was higher (P < 0. 05 in HS-CONT and HS-VIT than in HS-RO birds. Globulin was lower (P < 0. 05 in CONT than in HS

  1. Biofumigation with Brassica juncea, Raphanus sativus and Eruca sativa for the management of field populations of the potato cyst nematode Globodera pallida.

    Science.gov (United States)

    Ngala, Bruno M; Haydock, Patrick P J; Woods, Simon; Back, Matthew A

    2015-05-01

    The viability of potato cyst nematode (PCN) populations (Globodera pallida) was evaluated in three field experiments using Brassica juncea, Raphanus sativus and Eruca sativa amendments. These species were summer cultivated and autumn incorporated in experiment 1; in experiment 2, overwintered brassicaceous cover crops were spring incorporated. Experiment 3 involved determination of effects of metconazole application on biomass/glucosinolate production by B. juncea and R. sativus and on PCN pre- and post-incorporation. Glucosinolate contents were determined before incorporation. Following cover crop incorporation, field plots were planted with susceptible potatoes to evaluate the biofumigation effects on PCN reproduction. In experiment 1, PCN population post-potato harvest was reduced (P = 0.03) in B. juncea-treated plots, while R. sativus prevented further multiplication, but in experiment 2 there were no significant effects on PCN reproduction. In experiment 3, B. juncea or R. sativus either untreated or treated with metconazole reduced PCN populations. Glucosinolate concentrations varied significantly between different plant regions and cultivation seasons. Metconazole application increased the sinigrin concentration in B. juncea tissues. Glucosinolate concentrations correlated positively with PCN mortality for summer-cultivated brassicaceous plants. The results demonstrated that B. juncea and R. sativus green manures can play an important role in PCN management, particularly if included in an integrated pest management scheme. © 2014 Society of Chemical Industry.

  2. Comparación de variables físicas, culinarias y amilográficas del cultivar de arroz (Oryza sativa L. MD248 con dos cultivares comerciales de arroz en Venezuela

    Directory of Open Access Journals (Sweden)

    Manuel Ávila

    2014-12-01

    Full Text Available El objetivo del estudio fue evaluar las variables físicas culinarias y amilográficas del cultivar MD248 y su potencial como arroz de mesa en Venezuela. Para ello, MD248 se sembró bajo un diseño completamente aleatorizado, en Calabozo (Estado Guárico, Venezuela, junto con 2 cultivares empleados como testigos de buena (D-Sativa y baja (D-Primera calidad culinaria. De cada cultivar se cosecharon 2.500 g de arroz paddy y se procesaron hasta obtener una fracción de arroz entero pulido la cual fue evaluada para: largo, ancho, espesor, relación largo/ancho (L/A, peso de 100 granos, contenido de amilosa aparente, tiempo de cocción, relación de expansión volumétrica (REV, relación de absorción de agua (RAA, viscosidades pico, media, final, ‘breakdown’, ‘setback’, consistencia y temperatura de empaste del perfil amilográfico. Además, atributos sensoriales descriptivos (brillo, percepción visual de la adhesividad, adhesividad manual, adhesividad entre los granos y preferenciales (apariencia, adhesividad, calidad global del arroz cocido. Los resultados indicaron diferencias estadísticas altamente significativas (p ≤ 0,01 entre los cultivares para largo, relación L/A, peso de 100 granos, contenido de amilosa aparente, tiempo de cocción, REV, RAA y todas las variables amilográficas, excepto para viscosidad media y temperatura de empaste (p > 0,05. En los perfiles descriptivo y preferencial hubo diferencias altamente significativas (p ≤ 0,01 para todos los atributos evaluados. MD248 estuvo asociado con los mayores valores de largo de grano (7,07 mm, relación L/A (3,43, peso de 100 granos (2,20 g y amilosa aparente (19,14 %, y con los menores valores de tiempo de cocción (22,90 min, REV (3,07, RAA (1,55, viscosidad pico (159,61 RVU, media (130,10 RVU, p > 0,05 y ‘breakdown’ (29,51 RVU. MD248 presentó un perfil descriptivo comparable al cultivar de buena calidad culinaria y se diferenció ampliamente del cultivar de baja

  3. Phylogeography of Asian wild rice, Oryza rufipogon: a genome-wide view.

    Science.gov (United States)

    Huang, Pu; Molina, Jeanmaire; Flowers, Jonathan M; Rubinstein, Samara; Jackson, Scott A; Purugganan, Michael D; Schaal, Barbara A

    2012-09-01

    Asian wild rice (Oryza rufipogon) that ranges widely across the eastern and southern part of Asia is recognized as the direct ancestor of cultivated Asian rice (O. sativa). Studies of the geographic structure of O. rufipogon, based on chloroplast and low-copy nuclear markers, reveal a possible phylogeographic signal of subdivision in O. rufipogon. However, this signal of geographic differentiation is not consistently observed among different markers and studies, with often conflicting results. To more precisely characterize the phylogeography of O. rufipogon populations, a genome-wide survey of unlinked markers, intensively sampled from across the entire range of O. rufipogon is critical. In this study, we surveyed sequence variation at 42 genome-wide sequence tagged sites (STS) in 108 O. rufipogon accessions from throughout the native range of the species. Using Bayesian clustering, principal component analysis and amova, we conclude that there are two genetically distinct O. rufipogon groups, Ruf-I and Ruf-II. The two groups exhibit a clinal variation pattern generally from north-east to south-west. Different from many earlier studies, Ruf-I, which is found mainly in China and the Indochinese Peninsula, shows genetic similarity with one major cultivated rice variety, O. satvia indica, whereas Ruf-II, mainly from South Asia and the Indochinese Peninsula, is not found to be closely related to cultivated rice varieties. The other major cultivated rice variety, O. sativa japonica, is not found to be similar to either O. rufipogon groups. Our results support the hypothesis of a single origin of the domesticated O. sativa in China. The possible role of palaeoclimate, introgression and migration-drift balance in creating this clinal variation pattern is also discussed. © 2012 Blackwell Publishing Ltd.

  4. Screening of gamma radiation-induced pathogen resistance rice lines against Xanthomonas oryzae pv. oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Chan Ju; Lee, Ha Yeon; Kim, Woong Bom; Ahmad, Raza; Moon, Jae Sun; Kwon, Suk Yoon [Korea Research Institute of Beoscience and Biotechnology, Daejeon (Korea, Republic of); Kim, Dong Sub [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-09-15

    Bacterial blight is one of the most serious diseases of rice (Oryza sativa L.), and it has been known that Xanthomonas oryzae pv. oryzae (Xoo) causes this disease symptom. To develop resistance rice cultivars against Xoo, 3,000 lines of M{sub 3}, which were irradiated with gamma ray, were tested by 'scissor-dip method' primarily, and 191 putative resistant lines were selected. In M{sub 4} generation, these lines were screened again with various ways such as measuring of symptom of bacterial blight in leaf, number of tiller, fresh weight, and phenotypic segregation ratio in next generation. Finally, six resistance lines were selected. RT-PCR analysis revealed that these lines displayed high level of R-genes such as Xa21, Pi36, and Pi-ta. These results indicate that mutations by gamma ray cause disruptions of regulatory signal transduction systems of these R-genes. Furthermore, these selected mutants could be useful for the development of rice cultivar resistant to Xoo.

  5. Rim 2/Hipa CACTA transposon display ; A new genetic marker technique in Oryza species

    Directory of Open Access Journals (Sweden)

    Lee Ju

    2005-03-01

    Full Text Available Abstract Background Transposons constitute the major fractions of repetitive sequences in eukaryotes, and have been crucial in the shaping of current genomes. Transposons are generally divided into two classes according to the mechanism underlying their transposition: RNA intermediate class 1 and DNA intermediate class 2. CACTA is a class 2 transposon superfamily, which is found exclusively in plants. As some transposons, including the CACTA superfamily, are highly abundant in plant species, and their nucleotide sequences are highly conserved within a family, they can be utilized as genetic markers, using a slightly modified version of the conventional AFLP protocol. Rim2 /Hipa is a CACTA transposon family having 16 bp consensus TIR sequences to be present in high copy numbers in rice genome. This research was carried out in order to develop a Rim2/Hipa CACTA-AFLP or Rim2/Hipa CACTA-TD (transposon display, hereafter Rim2/Hipa-TD protocol for the study of genetic markers in map construction and the study of genetic diversity in rice. Results Rim2/Hipa-TD generated ample polymorphic profiles among the different rice accessions, and the amplification profiles were highly reproducible between different thermocyclers and Taq polymerases. These amplification profiles allowed for clear distinction between two different ecotypes, Japonica and Indica, of Oryza sativa. In the analysis of RIL populations, the Rim2/Hipa-TD markers were found to be segregated largely in a dominant manner, although in a few cases, non-parental bands were observed in the segregating populations. Upon linkage analysis, the Rim2/Hipa-TD markers were found to be distributed in the regions proximal to the centromeres of the chromosomes. The distribution of the Rim2/Hipa CACTA elements was surveyed in 15 different Oryza species via Rim2/Hipa-TD. While Rim2/Hipa-TD yielded ample amplification profiles between 100 to 700 bp in the AA diploid Oryza species, other species having BB, CC

  6. sativa L.) Cultivars

    African Journals Online (AJOL)

    Abstract. Ten rice cultivars from the International Rice Germplasm Centre originating from Bangladesh were analysedfor the~r genetics of resistance to bacterial blight. The test cultivars were selected on the basis of their high level ofresistance to races IV & VI ofXanthomonas oryzae pv. oryzae. The mode ofinheri- tance was ...

  7. Effector-mediated suppression of chitin-triggered immunity by Magnaporthe oryzae is necessary for rice blast disease

    NARCIS (Netherlands)

    Mentlak, T.A.; Kombrink, A.; Shinya, T.; Ryder, L.S.; Otomo, I.; Saitoh, H.; Terauchi, R.; Nishizawa, Y.; Shibuya, N.; Thomma, B.P.H.J.; Talbot, N.J.

    2012-01-01

    Plants use pattern recognition receptors to defend themselves from microbial pathogens. These receptors recognize pathogen-associated molecular patterns (PAMPs) and activate signaling pathways that lead to immunity. In rice (Oryza sativa), the chitin elicitor binding protein (CEBiP) recognizes

  8. Impact of elevated CO2 and temperature on soil C and N dynamics in relation to CH4 and N2O emissions from tropical flooded rice (Oryza sativa L.).

    Science.gov (United States)

    Bhattacharyya, P; Roy, K S; Neogi, S; Dash, P K; Nayak, A K; Mohanty, S; Baig, M J; Sarkar, R K; Rao, K S

    2013-09-01

    A field experiment was carried out to investigate the impact of elevated carbon dioxide (CO2) (CEC, 550 μmol mol(-1)) and elevated CO2+elevated air temperature (CECT, 550 μmol mol(-1) and 2°C more than control chamber (CC)) on soil labile carbon (C) and nitrogen (N) pools, microbial populations and enzymatic activities in relation to emissions of methane (CH4) and nitrous oxide (N2O) in a flooded alluvial soil planted with rice cv. Naveen in open top chambers (OTCs). The labile soil C pools, namely microbial biomass C, readily mineralizable C, water soluble carbohydrate C and potassium permanganate oxidizable C were increased by 27, 23, 38 and 37% respectively under CEC than CC (ambient CO2, 394 μmol mol(-1)). The total organic carbon (TOC) in root exudates was 28.9% higher under CEC than CC. The labile N fractions were also increased significantly (29%) in CEC than CC. Methanogens and denitrifier populations in rhizosphere were higher under CEC and CECT. As a result, CH4 and N2O-N emissions were enhanced by 26 and 24.6% respectively, under CEC in comparison to open field (UC, ambient CO2, 394 μmol mol(-1)) on seasonal basis. The global warming potential (GWP) was increased by 25% under CEC than CC. However, emissions per unit of grain yield under elevated CO2 and temperature were similar to those observed at ambient CO2. The stimulatory effect on CH4 and N2O emissions under CEC was linked with the increased amount of soil labile C, C rich root exudates, lowered Eh, higher Fe(+2) concentration and increased activities of methanogens and extracellular enzymes. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. An unedited 1.1 kb mitochondrial orfB gene transcript in the Wild Abortive Cytoplasmic Male Sterility (WA-CMS system of Oryza sativa L. subsp. indica

    Directory of Open Access Journals (Sweden)

    Maiti Mrinal K

    2010-03-01

    Full Text Available Abstract Background The application of hybrid rice technology has significantly increased global rice production during the last three decades. Approximately 90% of the commercially cultivated rice hybrids have been derived through three-line breeding involving the use of WA-CMS lines. It is believed that during the 21st century, hybrid rice technology will make significant contributions to ensure global food security. This study examined the poorly understood molecular basis of the WA-CMS system in rice. Results RFLPs were detected for atp6 and orfB genes in sterile and fertile rice lines, with one copy of each in the mt-genome. The RNA profile was identical in both lines for atp6, but an additional longer orfB transcript was identified in sterile lines. 5' RACE analysis of the long orfB transcript revealed it was 370 bp longer than the normal transcript, with no indication it was chimeric when compared to the genomic DNA sequence. cDNA clones of the longer orfB transcript in sterile lines were sequenced and the transcript was determined unedited. Sterile lines were crossed with the restorer and maintainer lines, and fertile and sterile F1 hybrids were respectively generated. Both hybrids contained two types of orfB transcripts. However, the long transcript underwent editing in the fertile F1 hybrids and remained unedited in the sterile lines. Additionally, the editing of the 1.1 kb orfB transcript co-segregated with fertility restoring alleles in a segregating population of F2 progeny; and the presence of unedited long orfB transcripts was detected in the sterile plants from the F2 segregating population. Conclusion This study helped to assign plausible operative factors responsible for male-sterility in the WA cytoplasm of rice. A new point of departure to dissect the mechanisms governing the CMS-WA system in rice has been identified, which can be applied to further harness the opportunities afforded by hybrid vigor in rice.

  10. PENGARUH RHIZOPUS ORYZAE DAN ASPERGILLUS ORYZAE TERHADAP KUALITAS KECAP

    Directory of Open Access Journals (Sweden)

    Dewi Sabita Slamet

    2012-11-01

    Full Text Available Telah diteliti pengganti fermentasi mikroorganisme Aspergillus oryzae Rhyzopus oryzae dan campuran Aspergillus dan Rhyzopus oryzae, dengan perendaman dalam larutan garam 20% dalam waktu yang berbeda terhadap kualitas kecap.Lamanya perendaman dalam larutan garam 20% yang berbeda menghasilkan kadar protein kecap yang berbeda. Aspergillus oryzae lebih baik dalam menghasilkan enzima protease dari pada Rhyzopus oryzae.Uji organoleptik menunjukkan perbedaan tidak bermakna dalam hal rasa maupun aroma antar kecap yang dibuat dengan strain jamur yang berlainan serta waktu perendaman yang berbeda. Untuk membuat kecap, sebaiknya dilakukan perendaman dalam larutan garam 20% selama 14 hari.

  11. Replenishment of Plant Varieties Market: Sown Rise (Oryza sativa L.)

    OpenAIRE

    Безручко, О. І.; Довгий, Ю. М.

    2010-01-01

    There discussed directions of use for the valuable groats crop, namely Rice, growth rates of its production in Ukraine, options and necessity of creation new verities by breeders, that favors not just the improved nutrition of people, but improves their health, too. And also a full description is provided for new varieties of soybean listed in the Sate Register of Plant Varieties Suitable for Dissemination in Ukraine.

  12. Hormonal regulation of floret closure of rice (Oryza sativa)

    Science.gov (United States)

    Huang, Youming; Zeng, Xiaochun

    2018-01-01

    Plant hormones play important roles in regulating every aspect of growth, development, and metabolism of plants. We are interested in understanding hormonal regulation of floret opening and closure in plants. This is a particularly important problem for hybrid rice because regulation of flowering time is vitally important in hybrid rice seed production. However, little was known about the effects of plant hormones on rice flowering. We have shown that jasmonate and methyl jasmonate play significant roles in promoting rice floret opening. In this study, we investigated the effects of auxins including indole-3-acidic acid (IAA), indole-3-butyric acid (IBA), 1-naphthalene-acetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 3,6-dichloro-2-methoxybenzoic acid (DIC) and abscisic acid (ABA) on floret closure of four fertile and three sterile varieties of rice. The results from field studies in three growing seasons in 2013–2015 showed that the percentages of closed florets were significantly lower in plants treated with IAA, IBA, 2,4-D, DIC and NAA and that the durations of floret opening were significantly longer in plants treated with the same auxins. The auxins exhibited time- and concentration-dependant effects on floret closure. ABA displayed opposite effects of auxins because it increased the percentages of floret closure and decreased the length of floret opening of rice varieties. The degree of auxin-inhibiting and ABA-promoting effects on floret closure was varied somewhat but not significantly different among the rice varieties. Endogenous IAA levels were the highest in florets collected shortly before opening followed by a sharp decline in florets with maximal angles of opening and a significant jump of IAA levels shortly after floret closure in both fertile and sterile rice plants. ABA levels showed an opposite trend in the same samples. Our results showed that auxins delayed but ABA promoted the closure of rice floret regardless of the varieties. PMID:29879200

  13. Hormonal regulation of floret closure of rice (Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Youming Huang

    Full Text Available Plant hormones play important roles in regulating every aspect of growth, development, and metabolism of plants. We are interested in understanding hormonal regulation of floret opening and closure in plants. This is a particularly important problem for hybrid rice because regulation of flowering time is vitally important in hybrid rice seed production. However, little was known about the effects of plant hormones on rice flowering. We have shown that jasmonate and methyl jasmonate play significant roles in promoting rice floret opening. In this study, we investigated the effects of auxins including indole-3-acidic acid (IAA, indole-3-butyric acid (IBA, 1-naphthalene-acetic acid (NAA, 2,4-dichlorophenoxy acetic acid (2,4-D and 3,6-dichloro-2-methoxybenzoic acid (DIC and abscisic acid (ABA on floret closure of four fertile and three sterile varieties of rice. The results from field studies in three growing seasons in 2013-2015 showed that the percentages of closed florets were significantly lower in plants treated with IAA, IBA, 2,4-D, DIC and NAA and that the durations of floret opening were significantly longer in plants treated with the same auxins. The auxins exhibited time- and concentration-dependant effects on floret closure. ABA displayed opposite effects of auxins because it increased the percentages of floret closure and decreased the length of floret opening of rice varieties. The degree of auxin-inhibiting and ABA-promoting effects on floret closure was varied somewhat but not significantly different among the rice varieties. Endogenous IAA levels were the highest in florets collected shortly before opening followed by a sharp decline in florets with maximal angles of opening and a significant jump of IAA levels shortly after floret closure in both fertile and sterile rice plants. ABA levels showed an opposite trend in the same samples. Our results showed that auxins delayed but ABA promoted the closure of rice floret regardless of the varieties.

  14. Genetic diversity analysis of stress tolerant rice (Oryza sativa L.)

    African Journals Online (AJOL)

    MD.Farid Islam

    2012-10-23

    Oct 23, 2012 ... The size (in nucleotide base pair) of the amplified band for each. SSR marker was determined based ..... Yield gaps, yield losses and constraints to ... in the red winter wheat regions of the United States. Proc. Natl. Acad. Sci.

  15. Molecular and genetic characterization of OSH6 (Oryza sativa ...

    African Journals Online (AJOL)

    Jane

    2011-03-07

    Mar 7, 2011 ... 2Policy Development Office, Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, .... Tissue samples were frozen in liquid nitrogen and .... organs before fertilization and this gene is suggested to.

  16. Characterization of wide cross derivatives in rice Oryza sativa L ...

    African Journals Online (AJOL)

    hope&shola

    2010-10-04

    Oct 4, 2010 ... Newly emerged roots (1 - 2 cm) from field grown F1 hybrid plants. (BC1, MAAL ... vectashield. The slides were screened with fluorescence micro- .... Brar DS, Dalmacio R, Eloloran R, Aggarwal R, Angels R, Khush GS. (1996).

  17. Genotypic differences in phosphate nutrition of rice (Oryza Sativa L.)

    International Nuclear Information System (INIS)

    Bui Thi Hong Thanh; Zapata, F.; Bowen, G.D.; Kumarasinghe, K.S.

    1996-01-01

    Phosphate uptake and use by five genotypes of paddy rice were studied at five phosphate levels in pot studies for 49 days. For all five P levels there were marked genotypic differences in shoot growth, plant dry weight, root/shoot ratios, phosphate uptake and translocation, P content of roots and shoots, and phosphorus use efficiency of shoots (PUE, g shoot mg P -1 in shoot). There were significant genotypic differences in root weight (4 P levels) and in uptake/mg root (all P levels). These latter may have resulted from differences in root weight/root length conversion, root hair development or uptake characteristics, factors which were not studied specifically. Differences between genotypes and P levels in the percentage translocation were partly explicable by differences in P uptake/plant (r = 0.72) but especially by differences in root/shoot ratios (r = 0.89). Differences in PUE were largely a factor of P percentage of the tops (r = 0.94) but significant differences between genotypes were shown as a function of % P. Differences in net photosynthesis rates were largely, but not entirely, due to differences in P % of the shoots. Key factors in P uptake and use and genotypic differences are root growth, uptake/mg root, root/shoot ratios and PUE. (author). 9 refs, 2 figs, 3 tabs

  18. A mutable slender glume gene in rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Okumoto, Yutaka; Teraishi, Masayosi; Tanisaka, Takatoshi [Kyoto Univ. (Japan). Graduate School of Agriculture; Yamagata, Hirotada; Horibata, Akira [Kinki Univ., Uchida, Osaka (Japan)

    1999-07-01

    Identification of genetic factors involved in the mutability of slender glume was made for further understanding of active transposable elements or epigenetic transformation in the rice genome. The results indicated that slender glume mutation is induced with a single recessive mutable gene, slg. The rate of reverse mutation was little affected by crossing, backcrossing, genetic background or cytoplasmic factors. To examine the inheritance of mutability in slg, the reverse mutation rate was evaluated using the progenies of F{sub 2}, F{sub 3}, BC{sub 1}F{sub 2} and BC{sub 1}F{sub 3} SGPs. It was suggested that background and cytoplasmic factors did not have noticeable effects on the reverse mutation frequency (RMF) thus on the mutability of slg. In most cases, the lines derived from slender glume panicles included slender glume plants (SGPs) in a ratio of more than 90%, while those derived from normal glume panicles did in a ratio of 10-20%. Thus, the genotype was concluded as slg/slg for the slender panicles and slg/+ for the normal ones, suggesting that the outer layer of the normal glumes in chimeric plants (CPs) has a genotype slg/+, whereas the inner one including embryo has a genotype of slg/slg. The appearance of such chimera plant is a clear indication of the occurrence of reverse mutation during mitosis as well as meiosis. RFLP linkage analysis showed that slg locus was located between XNpb33 and R1440 with the recombination values of 3.1 and 1.0 cM, respectively. The slg locus was identified to localize on the overlapping region of two YAC clones, Y1774 and Y3356 and the length of this region was assumed to be less than 280 kb. (M.N.)

  19. Genetic improvement of rice (oryza sativa l.) by induced mutations

    International Nuclear Information System (INIS)

    Suarez, E.; Deus, J. E.; Perez, R.; Alfonso, R.; Hernandez, R.; Avila, J.; Hernandez, J. L.; Puldon, Violeta; Duany, A.; Reinoso, J.; Mesa, H.; Rodriguez, S.

    2001-01-01

    In 1989 was initiated at Rice Research Institute of Cuba, a mutation breeding programme, in order to obtain new germoplasm with improved characters such as milling quality, earliness, resistance to the Hoja Blanca virus disease and salt tolerance. Seven varieties has been irradiated and two different sources of radiation were used: gamma rays from 60Co and fast neutrons of a 14 MeV neutron generator. In 1995, was released the variety IACuba 23 for low inputs conditions. Another four varieties IACuba 21, IACuba 22, IACuba 27 and IACuba 28 are in validation trials in rice production areas under irrigated condition. The last two have showed resistance to Steneotarsonemus spinki. Also, a group of mutants was selected to be used as parents. These mutants have been used in 953 crosses

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

    African Journals Online (AJOL)

    Mutation breeding can be considered successful in obtaining new cultivars and broadening the genetic base of rice crop. 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 rice cultivars ...

  1. Fungi and some mycotoxins contaminating rice ( Oryza Sativa ) in ...

    African Journals Online (AJOL)

    The major fungal genera contaminating rice were Aspergillus, Penicillium, Fusarium, Alternaria, Mucor, Rhizopus, Trichoderma, Curvularia, elminthosporium and Cladosporium. The most prevalent fungal species on rice were .Penicillium spp., A. flavus, A. parasiticus, A. niger, Mucor spp., Rhizopus spp. and Alternaria spp.

  2. Genotypic differences in phosphate nutrition of rice (Oryza Sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Hong Thanh, Bui Thi; Zapata, F [FAO/IAEA Agriculture and Biotechnology Lab., Seibersdorf (Austria). Soils Science Unit; Bowen, G D; Kumarasinghe, K S [Joint FAO/IAEA Div. of Nuclear Techniques in Food and Agriculture, Vienna (Austria). Soil Fertility, Irrigation and Crop Production Section

    1996-07-01

    Phosphate uptake and use by five genotypes of paddy rice were studied at five phosphate levels in pot studies for 49 days. For all five P levels there were marked genotypic differences in shoot growth, plant dry weight, root/shoot ratios, phosphate uptake and translocation, P content of roots and shoots, and phosphorus use efficiency of shoots (PUE, g shoot mg P{sup -1} in shoot). There were significant genotypic differences in root weight (4 P levels) and in uptake/mg root (all P levels). These latter may have resulted from differences in root weight/root length conversion, root hair development or uptake characteristics, factors which were not studied specifically. Differences between genotypes and P levels in the percentage translocation were partly explicable by differences in P uptake/plant (r = 0.72) but especially by differences in root/shoot ratios (r = 0.89). Differences in PUE were largely a factor of P percentage of the tops (r = 0.94) but significant differences between genotypes were shown as a function of % P. Differences in net photosynthesis rates were largely, but not entirely, due to differences in P % of the shoots. Key factors in P uptake and use and genotypic differences are root growth, uptake/mg root, root/shoot ratios and PUE. (author). 9 refs, 2 figs, 3 tabs.

  3. Determination of genetic variability of Asian rice (Oryza sativa L ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... diversity and relationship among thirty-five Asian cultivars of rice including 19 aromatic, 13 non- ... are promising and effective tools for measuring genetic .... efficients were employed by using Simqual sub-program in similarity.

  4. Grain Accumulation of Selenium Species in Rice (Oryza sativa L.)

    Science.gov (United States)

    Selenium (Se) is an essential micronutrient in which up to 1 billion people worldwide are deficient, causing a range of health disorders and potentially an increased risk of certain cancers. Consequently, there is much interest in Se biofortification of rice, the staple food for...

  5. Expression, purification and characterization of Oryza sativa L. NAD ...

    African Journals Online (AJOL)

    Jane

    2011-10-17

    Oct 17, 2011 ... yeast, fungi, plants, animals and humans. MEs catalyze ... Plant NADP-. MEs were induced by many biotic or abiotic stresses, such as pathogen (Sutherland, 1991), wounding, UV-B ..... (2006) showed that the single mutation.

  6. Assessment of genomic relationship between Oryza sativa and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-01

    Mar 1, 2010 ... For genomic in situ hybridization, genomic DNA from O. australiensis was used as probe for the mitotic and meiotic ... Wide hybridization is one of the plant breeding approaches ..... Disease and insect resistance in rice.

  7. arroz rojo (Oryza sativa L. en dos sistemas de labranza

    Directory of Open Access Journals (Sweden)

    Steven Brenes Prendas

    2006-01-01

    Full Text Available A lo largo de cuatro ciclos de cultivo de arroz anegado, entre los años 2003 y 2004, en la Hacienda El Pelón de la Bajura, Liberia, Guanacaste, Costa Rica, se determinó la distribución espacial de las poblaciones de arroz rojo en los sistemas de Siembra Directa sobre Rastrojos (SDR y en Labranza Mecanizada Convencional (LMC. Mediante levantamientos de malezas ubicados en puntos fijos a nivel de campo y con ayuda del programa Surfer, se logró construir mapas georeferenciales de dichas poblaciones. El sistema SDR logró disminuir el ritmo de crecimiento de las poblaciones, facilitando su manejo, por lo contrario el sistema LMC, favoreció: la distribución, el aumento y la densidad de las poblaciones de arroz rojo en el campo. Los mapas de georeferencia facilitarían la toma de decisiones en el manejo integrado del arroz rojo

  8. Some aspects of photoperiodism in rice (Oryza sativa L.)

    NARCIS (Netherlands)

    Best, R.

    1961-01-01

    Photoperiodism was studied in 417 rice varieties of which 28, selected by differences in photoperiodic response, were studied in more detail. The plants were usually grown under 16 different photoperiods ranging from 5 to 24 h. In detailed experiments the types of response to short and long days

  9. 10559 A NATIONAL SURVEY OF RICE (ORYZA SATIVA L.) GRAIN ...

    African Journals Online (AJOL)

    User

    The study provided quantitative measures of the quality status of rice grains available in Sierra ... using the most convenient methods at their disposal. ... rice, moisture content of grains and percentages of foreign matter, chalky immature grains ...

  10. glucuronidase gene in indica and japonica rice (Oryza sativa L.)

    African Journals Online (AJOL)

    Plasmid pUCGUS containing the uidA gene encoding β- lucuronidase was used to optimize transformation conditions using various combinations of helium pressure, target distance and gap distance. Plasmid pHX4 carrying hygromycin phosphotransferase (hph) gene and pUCGUS was used for co bombardment.

  11. 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 ...

  12. 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...

  13. IDENTIFICATION AND MAPPING OF A GENE FOR RICE SLENDER KERNEL USING Oryza glumaepatula INTROGRESSION LINES

    Directory of Open Access Journals (Sweden)

    Sobrizal Sobrizal

    2016-10-01

    Full Text Available World demand for superior rice grain quality tends to increase. One of the  criteria of appearance quality of rice grain is grain shape. Rice consumers  exhibit wide preferences for grain shape, but most Indonesian rice consumers prefer long and slender grain. The objectives of this study were to identify and map a gene for rice slender kernel trait using Oryza  glumaepatula introgression lines with O. sativa cv. Taichung 65 genetic background. A segregation analysis of BC4F2 population derived from backcrosses of a donor parent O. glumaepatula into a recurrent parent Taichung 65 showed that the slender kernel was controlled by a single recessive gene. This new identified gene was designated as sk1 (slender kernel 1. Moreover, based on the RFLP analyses using 14 RFLP markers located on chromosomes 2, 8, 9, and 10 in which the O. glumaepatula chromosomal segments were retained in BC4F2 population, the sk1 was located between RFLP markers C679 and C560 on the long arm of chromosome 2, with map distances of 2.8 and 1.5 cM, respectively. The wild rice O. glumaepatula carried a recessive allele for slender kernel. This allele may be useful in breeding of rice with slender kernel types. In addition, the development of plant materials and RFLP map associated with slender kernel in this study is the preliminary works in the effort to isolate this important grain shape gene.

  14. Malaysian weedy rice shows its true stripes: wild Oryza and elite rice cultivars shape agricultural weed evolution in Southeast Asia.

    Science.gov (United States)

    Song, Beng-Kah; Chuah, Tse-Seng; Tam, Sheh May; Olsen, Kenneth M

    2014-10-01

    Weedy rice is a close relative of domesticated rice (Oryza sativa) that competes aggressively with the crop and limits rice productivity worldwide. Most genetic studies of weedy rice have focused on populations in regions where no reproductively compatible wild Oryza species occur (North America, Europe and northern Asia). Here, we examined the population genetics of weedy rice in Malaysia, where wild rice (O. rufipogon) can be found growing in close proximity to cultivated and weedy rice. Using 375 accessions and a combined analysis of 24 neutral SSR loci and two rice domestication genes (sh4, controlling seed shattering, and Bh4, controlling hull colour), we addressed the following questions: (i) What is the relationship of Malaysian weedy rice to domesticated and wild rice, and to weedy rice strains in the USA? (ii) To what extent does the presence of O. rufipogon influence the genetic and phenotypic diversity of Malaysian weeds? (iii) What do the distributions of sh4 and Bh4 alleles and associated phenotypes reveal about the origin and contemporary evolution of Malaysian weedy rice? Our results reveal the following: independent evolutionary origins for Malaysian weeds and US strains, despite their very close phenotypic resemblance; wild-to-weed gene flow in Malaysian weed populations, including apparent adaptive introgression of seed-shattering alleles; and a prominent role for modern Malaysian cultivars in the origin and recent proliferation of Malaysian weeds. These findings suggest that the genetic complexity and adaptability of weedy crop relatives can be profoundly influenced by proximity to reproductively compatible wild and domesticated populations. © 2014 John Wiley & Sons Ltd.

  15. WRKY transcription factor genes in wild rice Oryza nivara.

    Science.gov (United States)

    Xu, Hengjian; Watanabe, Kenneth A; Zhang, Liyuan; Shen, Qingxi J

    2016-08-01

    The WRKY transcription factor family is one of the largest gene families involved in plant development and stress response. Although many WRKY genes have been studied in cultivated rice (Oryza sativa), the WRKY genes in the wild rice species Oryza nivara, the direct progenitor of O. sativa, have not been studied. O. nivara shows abundant genetic diversity and elite drought and disease resistance features. Herein, a total of 97 O. nivara WRKY (OnWRKY) genes were identified. RNA-sequencing demonstrates that OnWRKY genes were generally expressed at higher levels in the roots of 30-day-old plants. Bioinformatic analyses suggest that most of OnWRKY genes could be induced by salicylic acid, abscisic acid, and drought. Abundant potential MAPK phosphorylation sites in OnWRKYs suggest that activities of most OnWRKYs can be regulated by phosphorylation. Phylogenetic analyses of OnWRKYs support a novel hypothesis that ancient group IIc OnWRKYs were the original ancestors of only some group IIc and group III WRKYs. The analyses also offer strong support that group IIc OnWRKYs containing the HVE sequence in their zinc finger motifs were derived from group Ia WRKYs. This study provides a solid foundation for the study of the evolution and functions of WRKY genes in O. nivara. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  16. Agro-ecological variations of sheath rot disease of rice caused by Sarocladium oryzae and DNA fingerprinting of the pathogen's population structure.

    Science.gov (United States)

    Tajul Islam Chowdhury, M; Salim Mian, M; Taher Mia, M A; Rafii, M Y; Latif, M A

    2015-12-28

    To examine the impact of regional and seasonal variations on the incidence and severity of sheath rot, a major seed-borne disease of rice caused by Sarocladium oryzae, data on incidence and severity were collected from 27 selected fields in the Gazipur, Rangpur, Bogra, Chittagong, Comilla, Gopalgonj, Jessore, Manikgonj, and Bhola districts of Bangladesh in rain-fed and irrigated conditions. Cultural variability of 29 pathogen isolates obtained from 8 different locations was studied on potato dextrose agar (PDA) and genetic variability was determined by DNA fingerprinting using variable number tandem repeat-polymerase chain reaction markers. Overall, disease incidence and severity were higher in irrigated rice. Disease incidence and severity were highest in the Bhola district in rain-fed rice and lowest in irrigated rice. Mycelial growth of 29 representative isolates was found to vary on PDA and the isolates were divided into 6 groups. The range of the overall size of conidia of the selected isolates was 2.40-7.20 x 1.20-2.40 μm. Analysis of the DNA fingerprint types of the 29 isolates of S. oryzae, obtained from the amplification reactions, revealed 10 fingerprinting types (FPTs) that were 80% similar. FPT-1 was the largest group and included 13 isolates (44.8%), while FPT-2 was the third largest group and included 3 isolates. Each of FPT-3, 4, 5, and 6 included only 1 isolate. We observed no relationship between cultural and genetic groupings.

  17. Ecogeographic variation in the morphology of two Asian wild rice species Oryza nivara and O. ruftipogon.

    NARCIS (Netherlands)

    Banaticla, M.C.N.; Sosef, M.S.M.; McNally, K.L.; Sackville Hamilton, R.; Berg, van den R.G.

    2013-01-01

    To search for variation patterns and diagnostic features between Asian wild rice species, several numerical methods were applied to phenotypic data obtained from 116 accessions representing sympatric populations of Oryza nivara and Oryza rufipogon from tropical continental Asia and O. rufipogon

  18. 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.

  19. The rice XA21 ectodomain fused to the Arabidopsis EFR cytoplasmic domain confers resistance to Xanthomonas oryzae pv. oryzae.

    Science.gov (United States)

    Thomas, Nicholas C; Oksenberg, Nir; Liu, Furong; Caddell, Daniel; Nalyvayko, Alina; Nguyen, Yen; Schwessinger, Benjamin; Ronald, Pamela C

    2018-01-01

    Rice ( Oryza sativa ) plants expressing the XA21 cell-surface receptor kinase are resistant to Xanthomonas oryzae pv. oryzae (Xoo) infection. We previously demonstrated that expressing a chimeric protein containing the ELONGATION FACTOR Tu RECEPTOR (EFR) ectodomain and the XA21 endodomain (EFR:XA21) in rice does not confer robust resistance to Xoo . To test if the XA21 ectodomain is required for Xoo resistance, we produced transgenic rice lines expressing a chimeric protein consisting of the XA21 ectodomain and EFR endodomain (XA21:EFR) and inoculated these lines with Xoo . We also tested if the XA21:EFR rice plants respond to a synthetic sulfated 21 amino acid derivative (RaxX21-sY) of the activator of XA21-mediated immunity, RaxX. We found that five independently transformed XA21:EFR rice lines displayed resistance to Xoo as measured by lesion length analysis, and showed that five lines share characteristic markers of the XA21 defense response (generation of reactive oxygen species and defense response gene expression) after treatment with RaxX21-sY. Our results indicate that expression of the XA21:EFR chimeric receptor in rice confers resistance to Xoo . These results suggest that the endodomain of the EFR and XA21 immune receptors are interchangeable and the XA21 ectodomain is the key determinant conferring robust resistance to Xoo .

  20. Genomic patterns of nucleotide diversity in divergent populations of U.S. weedy rice

    Directory of Open Access Journals (Sweden)

    Olsen Kenneth M

    2010-06-01

    Full Text Available Abstract Background Weedy rice (red rice, a conspecific weed of cultivated rice (Oryza sativa L., is a significant problem throughout the world and an emerging threat in regions where it was previously absent. Despite belonging to the same species complex as domesticated rice and its wild relatives, the evolutionary origins of weedy rice remain unclear. We use genome-wide patterns of single nucleotide polymorphism (SNP variation in a broad geographic sample of weedy, domesticated, and wild Oryza samples to infer the origin and demographic processes influencing U.S. weedy rice evolution. Results We find greater population structure than has been previously reported for U.S. weedy rice, and that the multiple, genetically divergent populations have separate origins. The two main U.S. weedy rice populations share genetic backgrounds with cultivated O. sativa varietal groups not grown commercially in the U.S., suggesting weed origins from domesticated ancestors. Hybridization between weedy groups and between weedy rice and local crops has also led to the evolution of distinct U.S. weedy rice populations. Demographic simulations indicate differences among the main weedy groups in the impact of bottlenecks on their establishment in the U.S., and in the timing of divergence from their cultivated relatives. Conclusions Unlike prior research, we did not find unambiguous evidence for U.S. weedy rice originating via hybridization between cultivated and wild Oryza species. Our results demonstrate the potential for weedy life-histories to evolve directly from within domesticated lineages. The diverse origins of U.S. weedy rice populations demonstrate the multiplicity of evolutionary forces that can influence the emergence of weeds from a single species complex.

  1. Utilization of Toxic Activities of Some Plant Oils for Increasing The Protection of Induced Tolerance Percentage With Gamma Rays to The Infestation by Sitophilus oryzae (L.)and Rhyzopertha dominica (F.) in two Wheat Irradiated Populations

    International Nuclear Information System (INIS)

    Darwish, A.A.A.; EI-Lakwah, F.A.M.; Ragab, A.I.; Boshra, S.A.; Mehany, A.L.

    2014-01-01

    In this study, the grains of PG 400 were treated with different concentrations of essential oils for Clove flowering buds, Dill seeds, Pinus syluestris and Lemon grass. However grains of PS 400 were only treated with different concentrations of Annis seeds. The obtained result showed that adults mortality percentage increased by increasing concentration and exposure time of the tested insects. After 14 days from the initial treatment, mortalities were between 83.3-100, 86.7-100, 82.3-100, 71-100 and 74.3-100 % at all tested concentrations with Clove flowering buds, Dill seeds, Pinus syluestris, Lemon grass and Annis seeds, respectively. However ,reduction in the progeny of S. oryzae was between 57.23-100,57.25-100,59.55-100,56.85-100 and 52.51-100% for Clove flowering buds, Dill seeds, Pinus syluestris, Lemon grass and Annis seeds, respectively However for R. dominica ,the adults mortality after 14 days of initial treatment ranged from 36.7-100, 60-100, 82.3-100, 55.7-100 and 61-100 % the various concentrations of Clove flowering buds, Dill seeds, Pinus syluestris, Lemion grass and Annis, respectively. While their ,reduction in the progeny ranged from 42,24-100,53.16-100,48.38-100,63.89-100 and 55.18-100% at various concentrations of Clove flowering buds, Dill seeds, Pinus syluestris, Lemon grass and Annis, respectively. The obtained results showed that high concentration of different essential oils caused about 100% mortality and progeny reduction ,but the low concentration caused about 70% mortality and progeny reduction .This study suggesting that the low oil concentration could be used to increase the protection for irradiated tolerant populations PG 400 and PS 400 from the infestation with S. oryzae and R. dominica as a complementary tool for pest control .

  2. Elimination of Sitophilus oryzae (L.) by irradiation

    International Nuclear Information System (INIS)

    Castro, Fernanda Peixoto

    2005-01-01

    Food treatment by exposure to ionizing radiation, known as food irradiation, presents several attractive features such as: leaving no residues, posing no threat to consumer health, usually causing no damage to sensory or nutritional properties and acting uniformly throughout the volume of the products. This work investigated the efficiency of irradiation for eliminating Sitophilus oryzae (L.), also known as 'the rice weevil', a small beetle frequently found in infested grains. A total of 444 individuals of Sitophilus oryzae (L.) found in corn meal and noodles supplies were irradiated with gamma ray doses of 0, 0.6, 0.9, 1.0, 1.2, 1.5 and 2.0 kGy and then visually monitored for 4 days in order to determine the number of insects still alive. The least-squares fitting method was used to determine the survival curves as functions of post-irradiation time and dose. The living fraction of the irradiated population was found to decrease exponentially with time. The results indicated that doses of 2.0, 1.5 and 0.6 kGy cause immediate death, instantaneous immobility and death of the species within one week, respectively. The findings suggest that disinfestation of Sitophilus oryzae (L.) by irradiation is an interesting option to the dangerous use of toxic chemicals. (author)

  3. Elimination of Sitophilus oryzae (L.) by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Fernanda Peixoto [Exercito Brasileiro, Brasilia, DF (Brazil). Diretoria de Suprimento. Dept. Logistico]. E-mail: peixotocastro@dlog.eb.mil.br; Vital, Helio de Carvalho [Centro Tecnologico do Exercito (CTEx), Rio de Janeiro, RJ (brazil)]. E-mail: vital@ctex.eb.br

    2005-07-01

    Food treatment by exposure to ionizing radiation, known as food irradiation, presents several attractive features such as: leaving no residues, posing no threat to consumer health, usually causing no damage to sensory or nutritional properties and acting uniformly throughout the volume of the products. This work investigated the efficiency of irradiation for eliminating Sitophilus oryzae (L.), also known as 'the rice weevil', a small beetle frequently found in infested grains. A total of 444 individuals of Sitophilus oryzae (L.) found in corn meal and noodles supplies were irradiated with gamma ray doses of 0, 0.6, 0.9, 1.0, 1.2, 1.5 and 2.0 kGy and then visually monitored for 4 days in order to determine the number of insects still alive. The least-squares fitting method was used to determine the survival curves as functions of post-irradiation time and dose. The living fraction of the irradiated population was found to decrease exponentially with time. The results indicated that doses of 2.0, 1.5 and 0.6 kGy cause immediate death, instantaneous immobility and death of the species within one week, respectively. The findings suggest that disinfestation of Sitophilus oryzae (L.) by irradiation is an interesting option to the dangerous use of toxic chemicals. (author)

  4. The Potency of White Rice (Oryza sativa), Black Rice (Oryza sativa L. indica), and Red Rice (Oryza nivara) as Antioxidant and Tyrosinase Inhibitor

    Science.gov (United States)

    Batubara, I.; Maharni, M.; Sadiah, S.

    2017-04-01

    Rice is known to have many beneficial biological activities and is often used as “bedak dingin”, a face powder. The content of vitamins, minerals, fiber, and several types of antioxidants, such as ferulic acid, phytic acid, tocopherol, and oryzanols [1-2] are predicted to be potential as a tyrosinase inhibitor. The purpose of this study is to determine the potency of extracts from there types of rice, namely white, red, and black rice as an antioxidant and tyrosinase inhibitor. The rice was extracted with three different solvents, n-hexane, ethyl acetate, and methanol. The results showed that the highest antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl method was found in the methanol extract of black rice (IC50 290 μg/mL). Meanwhile, ethyl acetate extract of white rice has the highest antioxidant activity withphosphomolybdic acid method (41 mmol α-tocopherol equivalents/g sample). Thus, methanol extract of black rice and ethyl acetate extract of white rice are potential as an antioxidant. For tyrosinase inhibitor, n-hexane extract of red rice (IC50 3156 μg/mL) was the most active extract. The active component for radical scavenging is polar compound and for antioxidant by phosphomolybdate method is less polar compounds in black rice methanol extract based on TLC bioautogram. In conclusion, the black rice is the most potent in antioxidant while red rice is for tyrosinase inhibition.

  5. Nigella sativa L.

    African Journals Online (AJOL)

    ajl yemi

    2011-10-26

    Oct 26, 2011 ... and agro-biodiversity in black cumin (Nigella sativa L.) genotypes from ... analysis. INTRODUCTION. Among the medicinal plants in use from prehistoric times, .... AA240 FS Fast sequential atomic absorption spectrophotometer) ... Lead (Pb) mg kg- ..... for herbal, pharmaceutical, neutraceutical and cosmetic.

  6. Assessment of genetic diversity of Xanthomonas oryzae pv. oryzae

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Bacterial blight of rice, caused by Xanthomonas oryzae pv. Oryzae(Xoo. ), is one of the major rice diseases in China. Making clear the shift of genetic diversity of the pathogen will provide important information for rice breeding. Strains collected from 11 provinces located in Southern region of the Changjiang River in China were assessed by using inoculation method and IS-PCR(Insertion Sequence-Based Polymerase Chain Reaction) analysis.

  7. Growth promotion and inhibition of the Amazonian wild rice species Oryza grandiglumis to survive flooding.

    Science.gov (United States)

    Okishio, Takuma; Sasayama, Daisuke; Hirano, Tatsuya; Akimoto, Masahiro; Itoh, Kazuyuki; Azuma, Tetsushi

    2014-09-01

    In Asian cultivated rice (Oryza sativa), distinct mechanisms to survive flooding are activated in two groups of varieties. Submergence-tolerant rice varieties possessing the SUBMERGENCE1A (SUB1A) gene display reduced growth during flash floods at the seedling stage and resume growth after the flood recedes, whereas deepwater rice varieties possessing the SNORKEL1 (SK1) and SNORKEL2 (SK2) genes display enhanced growth based on internodal elongation during prolonged submergence at the mature stage. In this study, we investigated the occurrence of these growth responses to submergence in the wild rice species Oryza grandiglumis, which is native to the Amazon floodplains. When subjected to gradual submergence, adult plants of O. grandiglumis accessions showed enhanced internodal elongation with rising water level and their growth response closely resembled that of deepwater varieties of O. sativa with high floating capacity. On the other hand, when subjected to complete submergence, seedlings of O. grandiglumis accessions displayed reduced shoot growth and resumed normal growth after desubmergence, similar to the response of submergence-tolerant varieties of O. sativa. Neither SUB1A nor the SK genes were detected in the O. grandiglumis accessions. These results indicate that the O. grandiglumis accessions are capable of adapting successfully to flooding by activating two contrasting mechanisms as the situation demands and that each mechanism of adaptation to flooding is not mediated by SUB1A or the SK genes.

  8. Characterisation of some Accessions of Indigenous Rice (Oryza glaberrima Steud) in Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Doku, H. A

    2011-07-15

    African rice (Oryza glaberrima Steud), a relative of the commonly consumed Asian (white) rice (Oryza sativa L.) is resistant to a number of biotic and abiotic stress factors and contains higher amounts of some essential mineral elements required for human health and growth, compared to the latter. Seventeen local accessions collected from four geographical regions in Ghana were characterised alongside NERICA 1, a high yielding, protein-rich hybrid line purposely bred for Africa, using 32 IBPGR-IRRI agro-botanical traits. Molecular characterisation was done using 24 standard simple sequence repeat markers. The accessions were also evaluated for seven essential mineral elements: calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), Manganese (Mn), potassium (K) and zinc (Zn) in the caryopsis, using Atomic Absorption Spectrophotometry (AAS) supported by Neutron Activation Analysis (NAA). The aim was to assess genetic diversity of the accessions and identify superior ones for incorporation in future breeding programmes. Cluster analysis (UPGMA), principal component analysis (Axes), correlation and population genetic analysis were used to group the accessions. The single link cluster technique classified the qualitative and quantitative traits of 18 accessions into six and four clusters respectively while the use of molecular traits grouped them into four clusters. Principal component analysis (PCA) re-ordered the accessions into four broad groups which had within-cluster and inter-cluster variations. Two pairs of duplicate accessions were revealed from the dendogram generated using morphological characters. SSRs were highly polymorphic, more discriminatory and informative at 77.3% and 80.0% similarity distance respectively, they were able to discriminate between these pairs of accessions earlier identified as duplicates using botanical descriptors. The overall genetic diversity of the accessions was relatively high (He = 0.625; Nei's He = 0.608 and I = 1.178) with

  9. Characterisation of some Accessions of Indigenous Rice (Oryza glaberrima Steud) in Ghana

    International Nuclear Information System (INIS)

    Doku, H. A

    2011-07-01

    African rice (Oryza glaberrima Steud), a relative of the commonly consumed Asian (white) rice (Oryza sativa L.) is resistant to a number of biotic and abiotic stress factors and contains higher amounts of some essential mineral elements required for human health and growth, compared to the latter. Seventeen local accessions collected from four geographical regions in Ghana were characterised alongside NERICA 1, a high yielding, protein-rich hybrid line purposely bred for Africa, using 32 IBPGR-IRRI agro-botanical traits. Molecular characterisation was done using 24 standard simple sequence repeat markers. The accessions were also evaluated for seven essential mineral elements: calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), Manganese (Mn), potassium (K) and zinc (Zn) in the caryopsis, using Atomic Absorption Spectrophotometry (AAS) supported by Neutron Activation Analysis (NAA). The aim was to assess genetic diversity of the accessions and identify superior ones for incorporation in future breeding programmes. Cluster analysis (UPGMA), principal component analysis (Axes), correlation and population genetic analysis were used to group the accessions. The single link cluster technique classified the qualitative and quantitative traits of 18 accessions into six and four clusters respectively while the use of molecular traits grouped them into four clusters. Principal component analysis (PCA) re-ordered the accessions into four broad groups which had within-cluster and inter-cluster variations. Two pairs of duplicate accessions were revealed from the dendogram generated using morphological characters. SSRs were highly polymorphic, more discriminatory and informative at 77.3% and 80.0% similarity distance respectively, they were able to discriminate between these pairs of accessions earlier identified as duplicates using botanical descriptors. The overall genetic diversity of the accessions was relatively high (He = 0.625; Nei's He = 0.608 and I = 1.178) with

  10. Molecular detection of Xanthomonas oryzae pv. oryzae, Xanthomonas oryzae pv. oryzicola, and Burkholderia glumae in infected rice seeds and leaves

    Science.gov (United States)

    Polymerase chain reaction (PCR) is particularly useful for plant pathogen detection. In the present study, multiplex PCR and SYBR green real-time PCR were developed to facilitate simultaneous detection of three important rice pathogens, Xanthomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, and Bur...

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

    Directory of Open Access Journals (Sweden)

    Yiming Wang

    2014-12-01

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

  12. Selección preliminar de plantas de arroz con resistencia vertical A pyricularia oryzae Cav por inducción de mutaciones (ING

    Directory of Open Access Journals (Sweden)

    A Cruz

    2016-03-01

    Full Text Available Seeds of rice Oryza sativa L. cv. CR-1113 susceptible to blast disease Pyricularia oryzae Cav. Were subjected to gamma radiation with 60Co using doses of 15 and 20 krads to obtain and select mutant plants with vertical resistance to blast. A total of 80.000 rice plants per treatment were individually evaluated in the second mutant generation (M2 at tillering and panicle emergence. Vertical resistance was observed in 47 and 8 plants from the 15 and 20 krads treatments respectively.

  13. Genetic analysis and identification of SSR markers associated with rice blast disease in a BC2F1 backcross population.

    Science.gov (United States)

    Hasan, N; Rafii, M Y; Abdul Rahim, H; Nusaibah, S A; Mazlan, N; Abdullah, S

    2017-01-23

    Rice (Oryza sativa L.) blast disease is one of the most destructive rice diseases in the world. The fungal pathogen, Magnaporthe oryzae, is the causal agent of rice blast disease. Development of resistant cultivars is the most preferred method to achieve sustainable rice production. However, the effectiveness of resistant cultivars is hindered by the genetic plasticity of the pathogen genome. Therefore, information on genetic resistance and virulence stability are vital to increase our understanding of the molecular basis of blast disease resistance. The present study set out to elucidate the resistance pattern and identify potential simple sequence repeat markers linked with rice blast disease. A backcross population (BC 2 F 1 ), derived from crossing MR264 and Pongsu Seribu 2 (PS2), was developed using marker-assisted backcross breeding. Twelve microsatellite markers carrying the blast resistance gene clearly demonstrated a polymorphic pattern between both parental lines. Among these, two markers, RM206 and RM5961, located on chromosome 11 exhibited the expected 1:1 testcross ratio in the BC 2 F 1 population. The 195 BC 2 F 1 plants inoculated against M. oryzae pathotype P7.2 showed a significantly different distribution in the backcrossed generation and followed Mendelian segregation based on a single-gene model. This indicates that blast resistance in PS2 is governed by a single dominant gene, which is linked to RM206 and RM5961 on chromosome 11. The findings presented in this study could be useful for future blast resistance studies in rice breeding programs.

  14. OryzaGenome: Genome Diversity Database of Wild Oryza Species

    KAUST Repository

    Ohyanagi, Hajime

    2015-11-18

    The species in the genus Oryza, encompassing nine genome types and 23 species, are a rich genetic resource and may have applications in deeper genomic analyses aiming to understand the evolution of plant genomes. With the advancement of next-generation sequencing (NGS) technology, a flood of Oryza species reference genomes and genomic variation information has become available in recent years. This genomic information, combined with the comprehensive phenotypic information that we are accumulating in our Oryzabase, can serve as an excellent genotype-phenotype association resource for analyzing rice functional and structural evolution, and the associated diversity of the Oryza genus. Here we integrate our previous and future phenotypic/habitat information and newly determined genotype information into a united repository, named OryzaGenome, providing the variant information with hyperlinks to Oryzabase. The current version of OryzaGenome includes genotype information of 446 O. rufipogon accessions derived by imputation and of 17 accessions derived by imputation-free deep sequencing. Two variant viewers are implemented: SNP Viewer as a conventional genome browser interface and Variant Table as a textbased browser for precise inspection of each variant one by one. Portable VCF (variant call format) file or tabdelimited file download is also available. Following these SNP (single nucleotide polymorphism) data, reference pseudomolecules/ scaffolds/contigs and genome-wide variation information for almost all of the closely and distantly related wild Oryza species from the NIG Wild Rice Collection will be available in future releases. All of the resources can be accessed through http://viewer.shigen.info/oryzagenome/.

  15. Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Fu, Chunxiang; Hernandez, Timothy; Zhou, Chuanen; Wang, Zeng-Yu

    2015-01-01

    Alfalfa (Medicago sativa L.) is a high-quality forage crop widely grown throughout the world. This chapter describes an efficient protocol that allows for the generation of large number of transgenic alfalfa plants by sonication-assisted Agrobacterium-mediated transformation. Binary vectors carrying different selectable marker genes that confer resistance to phosphinothricin (bar), kanamycin (npt II), or hygromycin (hph) were used to generate transgenic alfalfa plants. Intact trifoliates collected from clonally propagated plants in the greenhouse were sterilized with bleach and then inoculated with Agrobacterium strain EHA105. More than 80 % of infected leaf pieces could produce rooted transgenic plants in 4-5 months after Agrobacterium-mediated transformation.

  16. Occurrence of alfalfa (Medicago sativa L.) populations along roadsides in southern Manitoba, Canada and their potential role in intraspecific gene flow.

    Science.gov (United States)

    Bagavathiannan, Muthukumar V; Gulden, Robert H; Van Acker, Rene C

    2011-04-01

    Alfalfa is a highly outcrossing perennial species that can be noticed in roadsides as feral populations. There remains little information available on the extent of feral alfalfa populations in western Canadian prairies and their role in gene flow. The main objectives of this study were (a) to document the occurrence of feral alfalfa populations, and (b) to estimate the levels of outcrossing facilitated by feral populations. A roadside survey confirmed widespread occurrence of feral alfalfa populations, particularly in alfalfa growing regions. The feral populations were dynamic and their frequency ranged from 0.2 to 1.7 populations km(-1). In many cases, the nearest feral alfalfa population from alfalfa production field was located within a distance sufficient for outcrossing in alfalfa. The gene flow study confirmed that genes can move back and forth between feral and cultivated alfalfa populations. In this study, the estimated outcrossing levels were 62% (seed fields to feral), 78% (feral to seed fields), 82% (hay fields to feral) and 85% (feral to feral). Overall, the results show that feral alfalfa plants are prevalent in alfalfa producing regions in western Canada and they can serve as bridges for gene flow at landscape level. Management of feral populations should be considered, if gene flow is a concern. Emphasis on preventing seed spill/escapes and intentional roadside planting of alfalfa cultivars will be particularly helpful. Further, realistic and pragmatic threshold levels should be established for markets sensitive to the presence of GE traits.

  17. Overcoming the species hybridization barrier by ploidy manipulation in the genus Oryza.

    Science.gov (United States)

    Tonosaki, Kaoru; Sekine, Daisuke; Ohnishi, Takayuki; Ono, Akemi; Furuumi, Hiroyasu; Kurata, Nori; Kinoshita, Tetsu

    2018-02-01

    In most eudicot and monocot species, interspecific and interploidy crosses generally display abnormalities in the endosperm that are the major cause of a post-zygotic hybridization barrier. In some eudicot species, however, this type of hybridization barrier can be overcome by the manipulation of ploidy levels of one parental species, suggesting that the molecular mechanisms underlying the species hybridization barrier can be circumvented by genome dosage. We previously demonstrated that endosperm barriers in interspecific and interploidy crosses in the genus Oryza involve overlapping but different mechanisms. This result contrasts with those in the genus Arabidopsis, which shows similar outcomes in both interploidy and interspecific crosses. Therefore, we postulated that an exploration of pathways for overcoming the species hybridization barrier in Oryza endosperm, by manipulating the ploidy levels in one parental species, might provide novel insights into molecular mechanisms. We showed that fertile hybrid seeds could be produced by an interspecific cross of female tetraploid Oryza sativa and male diploid Oryza longistaminata. Although the rate of nuclear divisions did not return to normal levels in the hybrid endosperm, the timing of cellularization, nucellus degeneration and the accumulation of storage products were close to normal levels. In addition, the expression patterns of the imprinted gene MADS87 and YUCCA11 were changed when the species barrier was overcome. These results suggest that the regulatory machinery for developmental transitions and imprinted gene expression are likely to play a central role in overcoming species hybridization barriers by genome dosage in the genus Oryza. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  18. Characterization and evolutionary analysis of ent-kaurene synthase like genes from the wild rice species Oryza rufipogon.

    Science.gov (United States)

    Toyomasu, Tomonobu; Miyamoto, Koji; Shenton, Matthew R; Sakai, Arisa; Sugawara, Chizu; Horie, Kiyotaka; Kawaide, Hiroshi; Hasegawa, Morifumi; Chuba, Masaru; Mitsuhashi, Wataru; Yamane, Hisakazu; Kurata, Nori; Okada, Kazunori

    2016-11-18

    Cultivated rice (Oryza sativa) possesses various labdane-related diterpene synthase genes, homologs of ent-copalyl diphosphate synthase (CPS) and ent-kaurene synthase (KS) that are responsible for the biosynthesis of phytohormone gibberellins. The CPS homologs and KS like (KSL) homologs successively converted geranylgeranyl diphosphate to cyclic diterpene hydrocarbons via ent-copalyl diphosphate or syn-copalyl diphosphate in O. sativa. Consequently, a variety of labdane-related diterpenoids, including phytoalexin phytocassanes, momilactones and oryzalexins, have been identified from cultivated rice. Our previous report indicated that the biosynthesis of phytocassanes and momilactones is conserved in Oryza rufipogon, the progenitor of Asian cultivated rice. Moreover, their biosynthetic gene clusters, containing OsCPS2 and OsKSL7 for phytocassane biosynthesis and OsCPS4 and OsKSL4 for momilactone biosynthesis, are also present in the O. rufipogon genome. We herein characterized O. rufipogon homologs of OsKSL5, OsKSL6, OsKSL8 responsible for oryzalexin S biosynthesis, and OsKSL10 responsible for oryzalexins A-F biosynthesis, to obtain more evolutionary insight into diterpenoid biosynthesis in O. sativa. Our phytoalexin analyses showed that no accumulation of oryzalexins was detected in extracts from O. rufipogon leaf blades. In vitro functional analyses indicated that unlike OsKSL10, O. rufipogon KSL10 functions as an ent-miltiradiene synthase, which explains the lack of accumulation of oryzalexins A-F in O. rufipogon. The different functions of KSL5 and KSL8 in O. sativa japonica to those in indica are conserved in each type of O. rufipogon, while KSL6 functions (ent-isokaurene synthases) are well conserved. Our study suggests that O. sativa japonica has evolved distinct specialized diterpenoid metabolism, including the biosynthesis of oryzalexins. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. DNA barcoding of the vegetable leafminer Liriomyza sativae Blanchard (Diptera: Agromyzidae) in Bangladesh

    Science.gov (United States)

    DNA barcoding revealed the presence of the polyphagous leafminer pest Liriomyza sativae Blanchard in Bangladesh. DNA barcode sequences for mitochondrial COI were generated for Agromyzidae larvae, pupae and adults collected from field populations across Bangladesh. BLAST sequence similarity searches ...

  20. Genetic transformation of lettuce ( Lactuca sativa ): A review | Dan ...

    African Journals Online (AJOL)

    Lettuce (Lactuca sativa L.) is a globally important leafy vegetable that can be grown worldwide. Due to the rapid growth of population and the human desire to progress, there have been a lot of studies made by researchers, especially in genetic engineering. Improvements in regeneration system and transformation ...

  1. Prediction of chemical composition of South African Medicago sativa ...

    African Journals Online (AJOL)

    The near infrared reflectance spectroscopy (NIRS) to predict chemical and digestibility parameters was investigated. Samples (n = 168) representing the spectral characteristics of the South African. Medicago sativa L. hay population were chemically analysed for the development of calibration equations. Values for r² and ...

  2. Hemp (Cannabis sativa L.).

    Science.gov (United States)

    Feeney, Mistianne; Punja, Zamir K

    2015-01-01

    Hemp (Cannabis sativa L.) suspension culture cells were transformed with Agrobacterium tumefaciens strain EHA101 carrying the binary plasmid pNOV3635. The plasmid contains a phosphomannose isomerase (PMI) selectable marker gene. Cells transformed with PMI are capable of metabolizing the selective agent mannose, whereas cells not expressing the gene are incapable of using the carbon source and will stop growing. Callus masses proliferating on selection medium were screened for PMI expression using a chlorophenol red assay. Genomic DNA was extracted from putatively transformed callus lines, and the presence of the PMI gene was confirmed using PCR and Southern hybridization. Using this method, an average transformation frequency of 31.23% ± 0.14 was obtained for all transformation experiments, with a range of 15.1-55.3%.

  3. [Index screening and comprehensive evaluation of phenotypic traits of low nitrogen tolerance using BILs population derived from Dongxiang wild rice (Oryza rufipogon Griff)].

    Science.gov (United States)

    Hu, Biao-lin; Li, Xia; Wan, Yong; Qiu, Zai-hui; Nie, Yuan-yuan; Xie, Jian-kun

    2015-08-01

    To identify the low nitrogen tolerance of Dongxiang wild rice (DXWR) and its progenies, ten phenotypic traits including plant height (PH), heading day (HD), panicle length (PL), number of effective tillers per plant (NETP), number of filled grains per panicle (NFGP), number of grains per panicle (NGP), grain density (GD), spikelet fertility (SF), 1000-grain mass (TGM) and grain yield per plant (GYP) were studied under normal and low nitrogen treatments, using backcross inbred lines (BILs) of Xieqingzao B//DXWR/Xieqingzao B in BC1 F12. Comprehensive evaluation on the low nitrogen tolerance of the BILs population was conducted using principal component analysis and the subordinate function. The evaluation results indicated that the low nitrogen tolerance of the line 116, 143 and 157 was the strongest, which could be served as the intermediate materials for genetic studies on the low nitrogen tolerance of DXWR and breeding for the low nitrogen tolerance in rice. The optimal regression equation of the low nitrogen tolerance in rice was established using stepwise regression analysis. The relative values of five traits including PH, NGP, SF, TGM and GYP were screened out and could be used as comprehensive evaluation indices for the low nitrogen tolerance in the whole growth stage. Therefore, more attention should be paid to the relative values of these five traits, especially for NGP and GYP, in the genetic improvement of the low nitrogen tolerance in rice.

  4. Pengaruh Pemberian Kompos Jerami Dan Pupuk Sp-36 Pada Tanah Sulfat Masam Potensial Terhadap Perubahan Sifat Kimia Serta Pertumbuhan Dan Produksi Padi (Oriza Sativa L.)

    OpenAIRE

    Bhakari, Herlina Eka; Fauzi, Fauzi; Hanum, Hamidah

    2013-01-01

    The objective of this research was to study the effect of rice straw compost and the application ofphosphorus fertilizer of SP-36 on chemical characteristic of acid sulphate soils, rice growth andproduction (Oryza sativa L). This research was conducted in greenhouse agricultural departments,Universities Northen Sumatera, Medan. This study used a randomized block design factorial, with2 factors : factor 1 : rice straw compost treatment (J) wich consist of : J0 = 0 ton ha-1(0 g straw/pot); J1 =...

  5. Characterization of Cannabis sativa allergens.

    Science.gov (United States)

    Nayak, Ajay P; Green, Brett J; Sussman, Gordon; Berlin, Noam; Lata, Hemant; Chandra, Suman; ElSohly, Mahmoud A; Hettick, Justin M; Beezhold, Donald H

    2013-07-01

    Allergic sensitization to Cannabis sativa is rarely reported, but the increasing consumption of marijuana has resulted in an increase in the number of individuals who become sensitized. To date, little is known about the causal allergens associated with C sativa. To characterize marijuana allergens in different components of the C sativa plant using serum IgE from marijuana sensitized patients. Serum samples from 23 patients with a positive skin prick test result to a crude C sativa extract were evaluated. IgE reactivity was variable between patients and C sativa extracts. IgE reactivity to C sativa proteins in Western blots was heterogeneous and ranged from 10 to 70 kDa. Putative allergens derived from 2-dimensional gels were identified. Prominent IgE reactive bands included a 23-kDa oxygen-evolving enhancer protein 2 and a 50-kDa protein identified to be the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase. Additional proteins were identified in the proteomic analysis, including those from adenosine triphosphate synthase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and luminal binding protein (heat shock protein 70), suggesting these proteins are potential allergens. Deglycosylation studies helped refine protein allergen identification and demonstrated significant IgE antibodies against plant oligosaccharides that could help explain cross-reactivity. Identification and characterization of allergens from C sativa may be helpful in further understanding allergic sensitization to this plant species. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  6. Rubisco activity is associated with photosynthetic thermotolerance in a wild rice (Oryza meridionalis).

    Science.gov (United States)

    Scafaro, Andrew P; Yamori, Wataru; Carmo-Silva, A Elizabete; Salvucci, Michael E; von Caemmerer, Susanne; Atwell, Brian J

    2012-09-01

    Oryza meridionalis is a wild species of rice, endemic to tropical Australia. It shares a significant genome homology with the common domesticated rice Oryza sativa. Exploiting the fact that the two species are highly related but O. meridionalis has superior heat tolerance, experiments were undertaken to identify the impact of temperature on key events in photosynthesis. At an ambient CO(2) partial pressure of 38 Pa and irradiance of 1500 µmol quanta m(-2) s(-1), the temperature optimum of photosynthesis was 33.7 ± 0.8°C for O. meridionalis, significantly higher than the 30.6 ± 0.7°C temperature optimum of O. sativa. To understand the basis for this difference, we measured gas exchange and rubisco activation state between 20 and 42°C and modeled the response to determine the rate-limiting steps of photosynthesis. The temperature response of light respiration (R(light)) and the CO(2) compensation point in the absence of respiration (Γ(*)) were determined and found to be similar for the two species. C3 photosynthesis modeling showed that despite the difference in susceptibility to high temperature, both species had a similar temperature-dependent limitation to photosynthesis. Both rice species were limited by ribulose-1,5-bisphosphate (RuBP) regeneration at temperatures of 25 and 30°C but became RuBP carboxylation limited at 35 and 40°C. The activation state of rubisco in O. meridionalis was more stable at higher temperatures, explaining its greater heat tolerance compared with O. sativa. Copyright © Physiologia Plantarum 2012.

  7. Fine mapping and identification of a novel locus qGL12.2 control grain length in wild rice (Oryza rufipogon Griff.).

    Science.gov (United States)

    Qi, Lan; Ding, Yingbin; Zheng, Xiaoming; Xu, Rui; Zhang, Lizhen; Wang, Yanyan; Wang, Xiaoning; Zhang, Lifang; Cheng, Yunlian; Qiao, Weihua; Yang, Qingwen

    2018-04-19

    A wild rice QTL qGL12.2 for grain length was fine mapped to an 82-kb interval in chromosome 12 containing six candidate genes and none was reported previously. Grain length is an important trait for yield and commercial value in rice. Wild rice seeds have a very slender shape and have many desirable genes that have been lost in cultivated rice during domestication. In this study, we identified a quantitative trait locus, qGL12.2, which controls grain length in wild rice. First, a wild rice chromosome segment substitution line, CSSL41, was selected that has longer glume and grains than does the Oryza sativa indica cultivar, 9311. Next, an F 2 population was constructed from a cross between CSSL41 and 9311. Using the next-generation sequencing combined with bulked-segregant analysis and F 3 recombinants analysis, qGL12.2 was finally fine mapped to an 82-kb interval in chromosome 12. Six candidate genes were found, and no reported grain length genes were found in this interval. Using scanning electron microscopy, we found that CSSL41 cells are significantly longer than those of 9311, but there is no difference in cell widths. These data suggest that qGL12.2 is a novel gene that controls grain cell length in wild rice. Our study provides a new genetic resource for rice breeding and a starting point for functional characterization of the wild rice GL gene.

  8. Ehd4 encodes a novel and Oryza-genus-specific regulator of photoperiodic flowering in rice.

    Directory of Open Access Journals (Sweden)

    He Gao

    Full Text Available Land plants have evolved increasingly complex regulatory modes of their flowering time (or heading date in crops. Rice (Oryza sativa L. is a short-day plant that flowers more rapidly in short-day but delays under long-day conditions. Previous studies have shown that the CO-FT module initially identified in long-day plants (Arabidopsis is evolutionary conserved in short-day plants (Hd1-Hd3a in rice. However, in rice, there is a unique Ehd1-dependent flowering pathway that is Hd1-independent. Here, we report isolation and characterization of a positive regulator of Ehd1, Early heading date 4 (Ehd4. ehd4 mutants showed a never flowering phenotype under natural long-day conditions. Map-based cloning revealed that Ehd4 encodes a novel CCCH-type zinc finger protein, which is localized to the nucleus and is able to bind to nucleic acids in vitro and transactivate transcription in yeast, suggesting that it likely functions as a transcriptional regulator. Ehd4 expression is most active in young leaves with a diurnal expression pattern similar to that of Ehd1 under both short-day and long-day conditions. We show that Ehd4 up-regulates the expression of the "florigen" genes Hd3a and RFT1 through Ehd1, but it acts independently of other known Ehd1 regulators. Strikingly, Ehd4 is highly conserved in the Oryza genus including wild and cultivated rice, but has no homologs in other species, suggesting that Ehd4 is originated along with the diversification of the Oryza genus from the grass family during evolution. We conclude that Ehd4 is a novel Oryza-genus-specific regulator of Ehd1, and it plays an essential role in photoperiodic control of flowering time in rice.

  9. Adaptación del arroz riego (Oryza sativa L. en el Caribe colombiano Adaptation of irrigated rice (Oryza sativa L. in the colombian Caribbean

    Directory of Open Access Journals (Sweden)

    Hermes Aramendiz Tatis

    2011-01-01

    Full Text Available En Colombia, el arroz ocupa el primer lugar en seguridad alimentaria, valor económico y generación de empleo entre los cultivos anuales, siendo el sistema bajo riego más importante. El objetivo fue determinar el progreso, estabilidad y adaptabilidad del rendimiento de arroz bajo riego, en cinco departamentos del caribe colombiano. Se utilizaron datos del Ministerio de Agricultura y Desarrollo Rural, correspondiente a los Departamentos de Córdoba, Bolívar, Magdalena, Cesar y Guajira, durante el periodo 1987-2008. La estimación del progreso del rendimiento se realizó a través del análisis de regresión lineal entre los años (variable explicativa y el rendimiento de grano (variable explicada. La estabilidad se determinó a través del coeficiente de variación para tres períodos consecutivos de cinco años y el último de siete. La adaptabilidad, se realizó con el coeficiente de regresión lineal (bi. Los resultados destacan que el progreso en el rendimiento de grano en el Caribe colombiano, osciló entre 1.15% y 3.36% por año y 52.2 y 168.1 kg.ha-1, especialmente en el Departamento de Bolívar (3.36% por año y 168.1 kg.ha-1. La estabilidad, resultó en general alta (CV4.57 para el rendimiento de grano.In Colombia, the rice crop under irrigation system ranks first in food security, economic value and employment offer among annual crops, becoming the most important. The objective of this study was to quantify increasing, stability and adaptability of irrigated rice in five departments of the Colombian Caribbean area. Data from the Ministry of Agriculture and Rural Development for the departments of Cordoba, Bolivar, Magdalena, Cesar and Guajira, during the year period 1987 to 2008 were used. The increasing in yield was determined using the linear regression analysis among years (independent variable and grain yield (dependent variable in each department. The yield stability was determined by the coefficient of variation across of three consecutive periods of five years and the last seven years. The yield adaptability was estimated using linear regression coefficient (bi. The results indicate that progress in grain yield in the Colombian Caribbean, ranged from 1.15% to 3.36% per year and 52.2 to 168.1 kg.ha-1, especially in the department of Bolívar (3.36% per year and 168.1 kg.ha-1. The yield stability was generally high (CV4.57 for grain yield.

  10. Compuestos bioactivos en harinas integrales y salvados de arroz (Oryza sativa L. Bioactive compounds in rice (Oryza sativa L. | Wholemeals and brans

    Directory of Open Access Journals (Sweden)

    Carlos Aguilar-García

    2017-10-01

    Full Text Available El consumo regular de granos enteros y sus productos puede reducir el riesgo de enfermedades crónicas tales como: las cardiovasculares, diabetes tipo II y algunos tipos de cáncer. El objetivo de este estudio fue evaluar el contenido de compuestos bioactivos en harinas integrales y salvados de arroz (variedades: Cimarrón, FONAIAP 1 y Zeta 15, tales como: fibra dietética total (FDT, determinada por método enzimático-gravimétrico; inhibidores de tripsina (IT, ácido fítico (AF y taninos condensados (TC, cuantificados por colorimetría. Se encontraron diferencias significativas (p < 0,05 para los compuestos bioactivos entre las harinas integrales y los salvados. Los salvados son una fuente rica de FDT, AF y TC. La variedad Cimarrón exhibió el mayor contenido de FDT, en el salvado (40,61 ± 0,10% y en la harina (14,04 ± 0,12%; mientras que la FONAIAP 1 mostró el menor contenido en el salvado (33,67 ± 0,64% y la harina (11,44 ± 0,24%. Los IT en harinas y salvados presentaron un intervalo de 5,70 ± 0,02 a 6,35 ± 0,35 mg/g en todas las variedades, excepto en la harina Zeta 15 (3,72 ± 0,04 mg/g. Las concentraciones de AF y TC en los salvados, presentaron valores significativamente superiores con respecto a las harinas integrales. Los hallazgos demostraron que las harinas integrales y los salvados de arroz analizados en este estudio, pueden suministrar a la dieta importantes compuestos bioactivos (FDT, IT, AF y TC de gran significancia para la salud. Los salvados mostraron ser una fracción del arroz con alta concentración de FDT, AF y TC.

  11. Study of the resistance of Oryza sativa to Pyricularia oryzae by applying mutagenic techniques to the parasite

    International Nuclear Information System (INIS)

    Notteghem, J.L.

    1977-01-01

    The strategy for using resistant varieties is often based on hypotheses about the development of the genetic potential of the parasite when it encounters the resistance in question. An attempt has been made to find a method of studying experimentally how such resistance evolves through analysis of the pathogenic ability of artificial mutants of the parasite which are specific to the varieties of rice studied. With physical and chemical mutagens it has been possible to obtain a multivirulent strain and also variants similar to those found in nature. The results demonstrate the effectiveness of the method for investigating the variability of the parasite and the behaviour of resistant varieties in the face of this variability. (author)

  12. Pharmacology of Marihuana (Cannabis sativa)

    Science.gov (United States)

    Maickel, Roger P.

    1973-01-01

    A detailed discussion of marihuana (Cannabis sativa) providing the modes of use, history, chemistry, and physiologic properties of the drug. Cites research results relating to the pharmacologic effects of marihuana. These effects are categorized into five areas: behavioral, cardiovascular-respiratory, central nervous system, toxicity-toxicology,…

  13. Ortholog Alleles at Xa3/Xa26 Locus Confer Conserved Race-Specific Resistance against Xanthomonas oryzae in Rice

    Institute of Scientific and Technical Information of China (English)

    Hong-Jing Li; Xiang-Hua Li; Jing-Hua Xiao; Rod A. Wing; Shi-Ping Wang

    2012-01-01

    The rice disease resistance (R) gene Xa3/Xa26 (having also been named Xa3 and Xa26) against Xanthomonas oryzae pv.oryzae (Xoo),which causes bacterial blight disease,belongs to a multiple gene family clustered in chromosome 11 and is from an AA genome rice cultivar (Oryza sativa L.).This family encodes leucine-rich repeat (LRR) receptor kinasetype proteins.Here,we show that the orthologs (alleles) of Xa3/Xa26,Xa3/Xa26-2,and Xa3/Xa26-3,from wild Oryza species O.officinalis (CC genome) and O.minuta (BBCC genome),respectively,were also R genes against Xoo.Xa3/Xa26-2 and Xa3/Xa26-3 conferred resistance to 16 of the 18 Xoo strains examined.Comparative sequence analysis of the Xa3/Xa26 families in the two wild Oryza species showed that Xa3/Xa26-3 appeared to have originated from the CC genome of O.minuta.The predicted proteins encoded by Xa3/Xa26,Xa3/Xa26-2,and Xa3/Xa26-3 share 91-99% sequence identity and 94-99% sequence similarity.Transgenic plants carrying a single copy of Xa3/Xa26,Xa3/Xa26-2,or Xa3/Xa26-3,in the same genetic background,showed a similar resistance spectrum to a set of Xoo strains,although plants carrying Xa3/Xa26-2 or Xa3/Xa26-3 showed lower resistance levels than the plants carrying Xa3/Xa26.These results suggest that the Xa3/Xa26 locus predates the speciation of A and C genome,which is approximately 7.5 million years ago.Thus,the resistance specificity of this locus has been conserved for a long time.

  14. Genome-wide analysis of Dongxiang wild rice (Oryza rufipogon Griff.) to investigate lost/acquired genes during rice domestication.

    Science.gov (United States)

    Zhang, Fantao; Xu, Tao; Mao, Linyong; Yan, Shuangyong; Chen, Xiwen; Wu, Zhenfeng; Chen, Rui; Luo, Xiangdong; Xie, Jiankun; Gao, Shan

    2016-04-26

    It is widely accepted that cultivated rice (Oryza sativa L.) was domesticated from common wild rice (Oryza rufipogon Griff.). Compared to other studies which concentrate on rice origin, this study is to genetically elucidate the substantially phenotypic and physiological changes from wild rice to cultivated rice at the whole genome level. Instead of comparing two assembled genomes, this study directly compared the Dongxiang wild rice (DXWR) Illumina sequencing reads with the Nipponbare (O. sativa) complete genome without assembly of the DXWR genome. Based on the results from the comparative genomics analysis, structural variations (SVs) between DXWR and Nipponbare were determined to locate deleted genes which could have been acquired by Nipponbare during rice domestication. To overcome the limit of the SV detection, the DXWR transcriptome was also sequenced and compared with the Nipponbare transcriptome to discover the genes which could have been lost in DXWR during domestication. Both 1591 Nipponbare-acquired genes and 206 DXWR-lost transcripts were further analyzed using annotations from multiple sources. The NGS data are available in the NCBI SRA database with ID SRP070627. These results help better understanding the domestication from wild rice to cultivated rice at the whole genome level and provide a genomic data resource for rice genetic research or breeding. One finding confirmed transposable elements contribute greatly to the genome evolution from wild rice to cultivated rice. Another finding suggested the photophosphorylation and oxidative phosphorylation system in cultivated rice could have adapted to environmental changes simultaneously during domestication.

  15. Ultrastructure of Oryza glumaepatula , a wild rice species endemic of tropical America

    Directory of Open Access Journals (Sweden)

    Ethel Sánchez

    2005-06-01

    Full Text Available Oryza glumaepatula is a perennial wild rice species,endemic to tropical America, previously known as the Latin American race of Oryza rufipogon .In Costa Rica, it is found in the northern region of the country, mainly in the wetland of the Medio Queso River, Los Chiles, Alajuela. It is diploid, of AA type genome and because of its genetic relatedness to cultivated rice it is included in the O.sativa complex. We describe the ultrastructure of leaf blade, spikelet, ligule and auricles. Special emphasis is given to those traits of major taxonomic value for O.glumaepatula and to those characters that distinguish this species from O. rufipogon and O. sativa . O. glumaepatula has a leaf blade covered with tombstone-shaped, oblong and spheroid epicuticular wax papillae. It has diamond-shaped stomata surrounded by spherical papillae, rows of zipper-like silica cells, bulky prickle trichomes of ca .40 mu m in length and small hirsute trichomes of ca. 32 mu m in length.The central vein is covered with large,globular papillae of ca. 146 mu m in length,a characteristic that distinguishes this species from O.rufipogon and O.sativa. The border of the leaf blade exhibits a row of even-sized bulky prickle trichomes of ca .42.5 mu m in length.Auricles have attenuated trichomes of ca .5.5 mm in length on the edges and small bicellular trichomes of 120 mu m in length on the surface.The ligule has a large number of short attenuated trichomes on its surface of 100 mu m in length.These latter two traits have important taxonomic value since they were found in O.glumaepatula but not found in O.sativa or in O.rufipogon . The spikelet has the typical morphology of the Oryza genus. Fertile lemmas have abundant spines, a trait shared with O.rufipogon but not with O.sativa. The sterile lemmas are wing-shaped with serrated borders,a characteristic that distinguishes this species from O. rufipogon and O.sativa. All the ultrastructure characters observed in O.glumaepatula from

  16. Introgression from cultivated rice alters genetic structures of wild relative populations: implications for in situ conservation

    Science.gov (United States)

    Jin, Xin; Chen, Yu; Liu, Ping; Li, Chen; Cai, Xingxing; Rong, Jun

    2018-01-01

    Abstract Maintaining genetic integrity is essential for in situ and ex situ conservation of crop wild relative (CWR) species. However, introgression of crop alleles into CWR species/populations may change their genetic structure and diversity, resulting in more invasive weeds or, in contrast, the extinction of endangered populations. To determine crop-wild introgression and its consequences, we examined the genetic structure and diversity of six wild rice (Oryza rufipogon) populations under in situ conservation in China. Thirty-four simple sequence repeat (SSR) and 34 insertion/deletion markers were used to genotype the wild rice populations and two sets of rice cultivars (O. sativa), corresponding to the two types of molecular markers. Shared alleles and STRUCTURE analyses suggested a variable level of crop-wild introgression and admixture. Principal coordinates and cluster analyses indicated differentiation of wild rice populations, which was associated with the spatial distances to cultivated rice fields. The level of overall genetic diversity was comparable between wild rice populations and rice cultivars, but a great number of wild-specific alleles was detected in the wild populations. We conclude based on the results that crop-wild introgression can considerably alter the pattern of genetic structure and relationships of CWR populations. Appropriate measures should be taken for effective in situ conservation of CWR species under the scenario of crop-wild introgression. PMID:29308123

  17. Prevalence of sensitization to Cannabis sativa. Lipid-transfer and thaumatin-like proteins are relevant allergens.

    Science.gov (United States)

    Larramendi, Carlos H; López-Matas, M Ángeles; Ferrer, Angel; Huertas, Angel Julio; Pagán, Juan Antonio; Navarro, Luis Ángel; García-Abujeta, José Luis; Andreu, Carmen; Carnés, Jerónimo

    2013-01-01

    Although allergy to Cannabis sativa was first reported over 40 years ago, the allergenicity has scarcely been studied. The objectives of this study were to investigate the frequency of sensitization to this plant, to analyze the clinical characteristics and allergenic profile of sensitized individuals and to identify the allergens involved. Five hundred and forty-five individuals in Spain attending allergy clinics with respiratory or cutaneous symptoms underwent a skin-prick test (SPT) with C. sativa leaf extract. The extract was characterized by SDS-PAGE and 2-dimensional electrophoresis. Specific IgE to C. sativa was measured in positive SPT individuals. The clinical and allergenic profiles of sensitized individuals were investigated and the most-recognized allergens sequenced and characterized by liquid chromatography-mass spectrometry/mass spectrometry. Of this preselected population, 44 individuals had positive SPT to C. sativa (prevalence 8.1%). Prevalence was higher in individuals who were C. sativa smokers (14.6%). Two individuals reported mild symptoms with C. sativa. Twenty-one individuals from 32 available sera (65.6%) had positive specific IgE to C. sativa. Twelve sera recognized at least 6 different bands in a molecular-weight range of between 10 and 60 kDa. Six of them recognized a 10-kDa band, identified as a lipid transfer protein (LTP) and 8 recognized a 38-kDa band, identified as a thaumatin-like protein. There is a high prevalence of sensitization to C. sativa leaves. The clinical symptoms directly attributed to C. sativa were uncommon and mild. The sensitization profile observed suggests that C. sativa sensitization may be mediated by two mechanisms, i.e. cross-reactivity, mainly with LTP and thaumatin-like protein, and exposure-related 'de novo' sensitization. Copyright © 2013 S. Karger AG, Basel.

  18. Magnesium-induced alterations in the photosynthetic performance and resistance of rice plants infected with Bipolaris oryzae

    Directory of Open Access Journals (Sweden)

    Wiler Ribas Moreira

    2015-08-01

    Full Text Available Brown spot (BS, caused by the fungus Bipolaris oryzae, is one of the most important diseases contracted by rice. We investigated the effect of magnesium (Mg on the development of BS, caused by Bipolaris oryzae, and the effects of disease development on the photosynthetic performance of rice (Oryza sativa L. plants (cv. Metica-1 grown in nutrient solutions containing 0.25 or 4.0 mM of Mg. Assessments of BS severity, leaf Mg and pigment concentrations (total chlorophylls and carotenoids, were carried out at 120 h after inoculation, in addition to gas exchange parameters,. Higher leaf concentration of Mg was observed in plants supplied with 4.0 mM Mg than in those supplied with 0.25 mM. The increase in leaf Mg was accompanied by a decrease in BS severity, higher concentration of total chlorophyll and better photosynthetic performance. Plants supplied with 4.0 mM Mg had higher average values for carbon assimilation, stomatal conductance and internal leaf CO2 concentration when compared with plants supplied with 0.25 mM Mg. Conversely, the concentration of carotenoids was lower in plants supplied with the higher Mg rate. These results suggest that Mg suppresses disease severity and preserves photosynthetic performance by allowing for better stomatal conductance and, consequently, greater availability of CO2 at the carboxylation sites.

  19. A cell wall-degrading esterase of Xanthomonas oryzae requires a unique substrate recognition module for pathogenesis on rice.

    Science.gov (United States)

    Aparna, Gudlur; Chatterjee, Avradip; Sonti, Ramesh V; Sankaranarayanan, Rajan

    2009-06-01

    Xanthomonas oryzae pv oryzae (Xoo) causes bacterial blight, a serious disease of rice (Oryza sativa). LipA is a secretory virulence factor of Xoo, implicated in degradation of rice cell walls and the concomitant elicitation of innate immune responses, such as callose deposition and programmed cell death. Here, we present the high-resolution structural characterization of LipA that reveals an all-helical ligand binding module as a distinct functional attachment to the canonical hydrolase catalytic domain. We demonstrate that the enzyme binds to a glycoside ligand through a rigid pocket comprising distinct carbohydrate-specific and acyl chain recognition sites where the catalytic triad is situated 15 A from the anchored carbohydrate. Point mutations disrupting the carbohydrate anchor site or blocking the pocket, even at a considerable distance from the enzyme active site, can abrogate in planta LipA function, exemplified by loss of both virulence and the ability to elicit host defense responses. A high conservation of the module across genus Xanthomonas emphasizes the significance of this unique plant cell wall-degrading function for this important group of plant pathogenic bacteria. A comparison with the related structural families illustrates how a typical lipase is recruited to act on plant cell walls to promote virulence, thus providing a remarkable example of the emergence of novel functions around existing scaffolds for increased proficiency of pathogenesis during pathogen-plant coevolution.

  20. CatB is Critical for Total Catalase Activity and Reduces Bactericidal Effects of Phenazine-1-Carboxylic Acid on Xanthomonas oryzae pv. oryzae and X. oryzae pv. oryzicola.

    Science.gov (United States)

    Pan, Xiayan; Wu, Jian; Xu, Shu; Duan, Yabing; Zhou, Mingguo

    2017-02-01

    Rice bacterial leaf blight, caused by Xanthomonas oryzae pv. oryzae, and rice bacterial leaf streak, caused by X. oryzae pv. oryzicola, are major diseases of rice. Phenazine-1-carboxylic acid (PCA) is a natural product that is isolated from Pseudomonas spp. and is used to control many important rice diseases in China. We previously reported that PCA disturbs the redox balance, which results in the accumulation of reactive oxygen species in X. oryzae pv. oryzae. In this study, we found that PCA significantly upregulated the transcript levels of catB and katE, which encode catalases, and that PCA sensitivity was reduced when X. oryzae pvs. oryzae and oryzicola were cultured with exogenous catalase. Furthermore, catB deletion mutants of X. oryzae pvs. oryzae and oryzicola showed dramatically decreased total catalase activity, increased sensitivity to PCA, and reduced virulence in rice. In contrast, deletion mutants of srpA and katG, which also encode catalases, exhibited little change in PCA sensitivity. The results indicate that catB in both X. oryzae pvs. oryzae and oryzicola encodes a catalase that helps protect the bacteria against PCA-induced stress.

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

    Science.gov (United States)

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

    2016-01-01

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

  2. Carbon-14 dynamics in rice: an extension of the ORYZA2000 model

    Energy Technology Data Exchange (ETDEWEB)

    Galeriu, D.; Melintescu, A. [' ' Horia Hulubei' ' National Institute for Physics and Nuclear Engineering, Life and Environmental Physics Department, 30 Reactorului St., POB MG-6, Bucharest-Magurele (Romania)

    2014-03-15

    Carbon-14 ({sup 14}C) is a radionuclide of major interest in nuclear power production. The Fukushima accident changed the public attitude on the use of nuclear energy all over the world. In terms of nuclear safety, the need of quality-assured radiological models was emphasized by many international organizations, and for models used by decision-makers (i.e. regulatory environmental models and radiological models), a moderate conservatism, transparency, relative simplicity and user friendliness are required. Because the interaction between crops and the environment is complex and regulated by many feedback mechanisms, however, these requirements are difficult to accomplish. The present study makes a step forward regarding the development of a robust model dealing with food contamination after a short-term accidental emission and considers a single crop species, rice (Oryza sativa), one of the most widely used rice species. Old and more recent experimental data regarding the carbon dynamics in rice plants are reviewed, and a well-established crop growth model, ORYZA2000, is used and adapted in order to assess the dynamics of {sup 14}C in rice after a short-term exposure to {sup 14}CO{sub 2}. Here, the model is used to investigate the role of the genotype, management and weather on the concentration of radiocarbon at harvest. (orig.)

  3. Coordination of Leaf Photosynthesis, Transpiration, and Structural Traits in Rice and Wild Relatives (Genus Oryza).

    Science.gov (United States)

    Giuliani, Rita; Koteyeva, Nuria; Voznesenskaya, Elena; Evans, Marc A; Cousins, Asaph B; Edwards, Gerald E

    2013-07-01

    The genus Oryza, which includes rice (Oryza sativa and Oryza glaberrima) and wild relatives, is a useful genus to study leaf properties in order to identify structural features that control CO(2) access to chloroplasts, photosynthesis, water use efficiency, and drought tolerance. Traits, 26 structural and 17 functional, associated with photosynthesis and transpiration were quantified on 24 accessions (representatives of 17 species and eight genomes). Hypotheses of associations within, and between, structure, photosynthesis, and transpiration were tested. Two main clusters of positively interrelated leaf traits were identified: in the first cluster were structural features, leaf thickness (Thick(leaf)), mesophyll (M) cell surface area exposed to intercellular air space per unit of leaf surface area (S(mes)), and M cell size; a second group included functional traits, net photosynthetic rate, transpiration rate, M conductance to CO(2) diffusion (g(m)), stomatal conductance to gas diffusion (g(s)), and the g(m)/g(s) ratio.While net photosynthetic rate was positively correlated with gm, neither was significantly linked with any individual structural traits. The results suggest that changes in gm depend on covariations of multiple leaf (S(mes)) and M cell (including cell wall thickness) structural traits. There was an inverse relationship between Thick(leaf) and transpiration rate and a significant positive association between Thick(leaf) and leaf transpiration efficiency. Interestingly, high g(m) together with high g(m)/g(s) and a low S(mes)/g(m) ratio (M resistance to CO(2) diffusion per unit of cell surface area exposed to intercellular air space) appear to be ideal for supporting leaf photosynthesis while preserving water; in addition, thick M cell walls may be beneficial for plant drought tolerance.

  4. Structure, function, and phylogeny of the mating locus in the Rhizopus oryzae complex.

    Directory of Open Access Journals (Sweden)

    Andrii P Gryganskyi

    2010-12-01

    Full Text Available The Rhizopus oryzae species complex is a group of zygomycete fungi that are common, cosmopolitan saprotrophs. Some strains are used beneficially for production of Asian fermented foods but they can also act as opportunistic human pathogens. Although R. oryzae reportedly has a heterothallic (+/- mating system, most strains have not been observed to undergo sexual reproduction and the genetic structure of its mating locus has not been characterized. Here we report on the mating behavior and genetic structure of the mating locus for 54 isolates of the R. oryzae complex. All 54 strains have a mating locus similar in overall organization to Phycomyces blakesleeanus and Mucor circinelloides (Mucoromycotina, Zygomycota. In all of these fungi, the minus (- allele features the SexM high mobility group (HMG gene flanked by an RNA helicase gene and a TP transporter gene (TPT. Within the R. oryzae complex, the plus (+ mating allele includes an inserted region that codes for a BTB/POZ domain gene and the SexP HMG gene. Phylogenetic analyses of multiple genes, including the mating loci (HMG, TPT, RNA helicase, ITS1-5.8S-ITS2 rDNA, RPB2, and LDH genes, identified two distinct groups of strains. These correspond to previously described sibling species R. oryzae sensu stricto and R. delemar. Within each species, discordant gene phylogenies among multiple loci suggest an outcrossing population structure. The hypothesis of random-mating is also supported by a 50:50 ratio of plus and minus mating types in both cryptic species. When crossed with tester strains of the opposite mating type, most isolates of R. delemar failed to produce zygospores, while isolates of R. oryzae produced sterile zygospores. In spite of the reluctance of most strains to mate in vitro, the conserved sex locus structure and evidence for outcrossing suggest that a normal sexual cycle occurs in both species.

  5. Metagenome analysis of the root endophytic microbial community of Indian rice (O. sativa L.

    Directory of Open Access Journals (Sweden)

    Subhadipa Sengupta

    2017-06-01

    Full Text Available This study reports the root endophytic microbial community profile in rice (Oryza sativa L., the largest food crop of Asia, using 16S rRNA gene amplicon sequencing. Metagenome of OS01 and OS04 consisted of 11,17,900 sequences with 300 Mbp size and average 55.6% G + C content. Data of this study are available at NCBI Bioproject (PRJNA360379. The taxonomic analysis of 843 OTU's showed that the sequences belonged to four major phyla revealing dominance of Proteobacteria, Firmicutes, Cyanobacteria and Actinobacteria. Results reveal the dominance of Bacillus as major endophytic genera in rice roots, probably playing a key role in Nitrogen fixation.

  6. Bioactive spirans and other constituents from the leaves of Cannabis sativa f. sativa.

    Science.gov (United States)

    Guo, Tian-Tian; Zhang, Jian-Chun; Zhang, Hai; Liu, Qing-Chao; Zhao, Yong; Hou, Yu-Fei; Bai, Lu; Zhang, Li; Liu, Xue-Qiang; Liu, Xue-Ying; Zhang, Sheng-Yong; Bai, Nai-Sheng

    2017-08-01

    In this paper, 17 compounds (1-17) were isolated from the leaves of Hemp (Cannabis sativa f. sativa). Among the isolates, two were determined to be new spirans: cannabispirketal (1), and α-cannabispiranol 4'-O-β-D-glucopyranose (2) by 1D and 2D NMR spectroscopy, LC-MS, and HRESIMS. The known compounds 7, 8, 10, 13, 15, and 16 were isolated from Hemp (C. sativa f. sativa) for the first time. Furthermore, compounds 8 and 13 were isolated from the nature for the first time. All isolated compounds were evaluated for cytotoxicity on different tissue-derived passage cancer cell lines through cell viability and apoptosis assay. Among these compounds, compounds 5, 9 and 16 exhibited a broad-spectrum antitumor effect via inhibiting cell proliferation and promoting apoptosis. These results obtained have provided valuable clues to the understanding of the cytotoxic profile for these isolated compounds from Hemp (C. sativa f. sativa).

  7. Mitigation of Cd accumulation in paddy rice (Oryza sativa L.) by Fe fertilization.

    Science.gov (United States)

    Chen, Zhe; Tang, Ye-Tao; Yao, Ai-Jun; Cao, Jian; Wu, Zhuo-Hao; Peng, Zhe-Ran; Wang, Shi-Zhong; Xiao, Shi; Baker, Alan J M; Qiu, Rong-Liang

    2017-12-01

    Cadmium uptake in rice is believed to be mediated by the Fe transport system. Phyto-available Cd can be changed by Fe fertilization of substrates. This work investigated whether and how Fe fertilization affects mitigation of Cd accumulation in paddy rice. A 90-d soil column experiment was conducted to study the change of Cd and Fe availability in soil after Fe fertilization (ionic and chelated Fe). A low-Cd accumulating cultivar (TY116) and a high-Cd accumulating cultivar (JY841) were grown in two Cd-polluted paddy soils amended with chelated Fe fertilizers. Additionally, both cultivars were grown in hydroponics to compare Fe-related gene expression in EDDHAFe-deficient and EDDHAFe-sufficient roots. The column experiment showed that EDTANa 2 Fe(II) and EDDHAFe(III) fertilization had a better mitigation effect on soil Cd availability compared to FeSO 4 ·7H 2 O. Moreover, the field experiment demonstrated that these two chelated fertilizations could reduce Cd concentrations in brown rice by up to 80%. Iron concentrations in the brown rice were elevated by Fe chelates. Compared to EDDHAFe(III), EDTANa 2 Fe(II) fertilization had a stronger mitigation effect by generating more EDTANa 2 Cd(II) in the soil solution to decrease phyto-available Cd in the soil. While EDDHAFe(III) fertilization could increase soil pH and decrease soil Eh which contributed to decreasing phyto-available Cd in a contaminated soil. In the hydroponic experiment, Fe sufficiency significantly reduced Cd concentrations in above-ground organs. In some cases, the expression of OsIRT1, OsNRAMP1 and OsNRAMP5 was inhibited under Fe sufficiency relative to Fe deficiency conditions. These results suggest that mitigation of rice Cd by Fe chelate fertilization results from a decrease in available Cd in substrates and the inhibition of the expression of several Fe-related genes in the IRT and NRAMP families. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Biochemical indicators of root damage in rice (Oryza sativa) genotypes under zinc deficiency stress.

    Science.gov (United States)

    Lee, Jae-Sung; Wissuwa, Matthias; Zamora, Oscar B; Ismail, Abdelbagi M

    2017-11-01

    Zn deficiency is one of the major soil constraints currently limiting rice production. Although recent studies demonstrated that higher antioxidant activity in leaf tissue effectively protects against Zn deficiency stress, little is known about whether similar tolerance mechanisms operate in root tissue. In this study we explored root-specific responses of different rice genotypes to Zn deficiency. Root solute leakage and biomass reduction, antioxidant activity, and metabolic changes were measured using plants grown in Zn-deficient soil and hydroponics. Solute leakage from roots was higher in sensitive genotypes and linked to membrane damage caused by Zn deficiency-induced oxidative stress. However, total root antioxidant activity was four-fold lower than in leaves and did not differ between sensitive and tolerant genotypes. Root metabolite analysis using gas chromatography-mass spectrometry and high performance liquid chromatography indicated that Zn deficiency triggered the accumulation of glycerol-3-phosphate and acetate in sensitive genotypes, while less or no accumulation was seen in tolerant genotypes. We suggest that these metabolites may serve as biochemical indicators of root damage under Zn deficiency.

  9. Screening upland rice (Oryza sativa L. ssp. indica) genotypes for salt ...

    African Journals Online (AJOL)

    USER

    2010-07-26

    Jul 26, 2010 ... lamps (TLD 36W/84, Cool White, Philips, Thailand). Fourteen-day- ... were measured using a UV-visible spectrophotometer (DR/4000,. HACH ... measuring beam of far-red light (LED source with typical peak at wavelength ...

  10. Evaluation of bakanae disease progression caused by Fusarium fujikuroi in Oryza sativa L.

    Science.gov (United States)

    Hwang, In Sun; Kang, Woo-Ri; Hwang, Duk-Ju; Bae, Shin-Chul; Yun, Sung-Hwan; Ahn, Il-Pyung

    2013-12-01

    Bakanae disease caused by Fusarium fujikuroi is an important fungal disease in rice. Among the seven strains isolated from symptomatic rice grains in this study, one strain, FfB14, triggered severe root growth inhibition and decay in the crown and root of rice seedlings. The remaining six strains caused typical Bakanae symptoms such as etiolation and abnormal succulent rice growth. To reveal the relationship between mycelial growth in the infected tissues and Bakanae disease progression, we have established a reliable quantification method using real time PCR that employs a primer pair and dual-labeled probe specific to a unigene encoding F. fujikuroi PNG1 (FfPNG1), which is located upstream of the fumonisin biosynthesis gene cluster. Plotting the crossing point (CP) values from the infected tissue DNAs on a standard curve revealed the active fungal growth of FfB14 in the root and crown of rice seedlings, while the growth rate of FfB20 in rice was more than 4 times lower than FfB14. Massive infective mycelial growth of FfB14 was evident in rice stems and crown; however, FfB20 did not exhibit vigorous growth. Our quantitative evaluation system is applicable for the identification of fungal virulence factors other than gibberellin.

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

    Science.gov (United States)

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

    2005-03-09

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

  12. Transformation of haploid, microspore-derived cell suspension protoplasts of rice (Oryza sativa L.).

    Science.gov (United States)

    Chaïr, H; Legavre, T; Guiderdoni, E

    1996-06-01

    We compared the transient activity of three cereal gene-derived promoter-gus fusions and the efficiency of selection mediated by three different selectable genes in a polyethylene glycol transformation system with haploid cell suspension protoplasts of rice. The maize ubiquitin promoter was found to be the most active in transformed protoplasts, and selection on ammonium glufosinate mediated by the bar gene was the most efficient for producing resistant calluses. Cotransformation of protoplasts with two separate plasmids carrying the gus and the bar genes, at either a 2∶1 or 1∶1 ratio, led to 0.8 × 10(-5) and 1.6 × 10(-5) resistant callus recovery frequencies and 59.7 and 37.9 cotransformation efficiencies respectively. No escapes were detected in dot blot analyses of 100 resistant calluses with a probe consisting of the bar coding region. Cotransformation efficiency, based on resistance to basta and β-glucuronidase staining of the leaf tissue of 115 regenerated plants, was 47%. Resistance tests and Southern analysis of seed progenies of three diploid transgenic plants demonstrated homozygous integration of multiple copies of the transgene at one locus at least in the first plant, heterozygous integration at one locus in the second plant and heterozygous integration at two loci in the third plant.

  13. Vitamin E homologs and ¿-oryzanol levels in rice (Oryza sativa L.) during seed development

    Science.gov (United States)

    Vitamin E homologs (tocopherols and tocotrienols) and gamma-oryzanol have gained significant attention due to their proposed health benefits and ability to increase vegetable oil stability. Changes in the levels of these phytochemicals were examined during seed development. Rapid accumulation of toc...

  14. A Review of the “Omics” Approach to Biomarkers of Oxidative Stress in Oryza sativa

    Directory of Open Access Journals (Sweden)

    Su Shiung Lam

    2013-04-01

    Full Text Available Physiological and ecological constraints that cause the slow growth and depleted production of crops have raised a major concern in the agriculture industry as they represent a possible threat of short food supply in the future. The key feature that regulates the stress signaling pathway is always related to the reactive oxygen species (ROS. The accumulation of ROS in plant cells would leave traces of biomarkers at the genome, proteome, and metabolome levels, which could be identified with the recent technological breakthrough coupled with improved performance of bioinformatics. This review highlights the recent breakthrough in molecular strategies (comprising transcriptomics, proteomics, and metabolomics in identifying oxidative stress biomarkers and the arising opportunities and obstacles observed in research on biomarkers in rice. The major issue in incorporating bioinformatics to validate the biomarkers from different omic platforms for the use of rice-breeding programs is also discussed. The development of powerful techniques for identification of oxidative stress-related biomarkers and the integration of data from different disciplines shed light on the oxidative response pathways in plants.

  15. Physiochemical properties and cooking quality of long and short rice (Oryza sativa) grains

    International Nuclear Information System (INIS)

    Elbashir, L. T. M.

    2005-01-01

    Five rice grain samples namely long (American (Parboiled rice), A; Pakistan, P and Thailand, T) and short (Egyptian, E and Sudanese, S) types were investigated for their physicochemical and cooking quality characteristics. Investigations showed that rice grain of the two types had a length of 6.73 mm (A), 7.49 mm (P), 7.05 mm (T), 5.46 mm (E) and 5.64 mm (S); width of 2.08 mm (A), 1.73 mm (P), 2.06 mm (T), 2.66 mm (E) and 2.73 mm (S); thickness of 1.59 mm (A), 1.50 mm (P), 1.67 mm (T), 1.93 mm (E) and 1.83 mm (S) and length/width (L/w) ratio 3.24 (A), 4.35(P), 3.43 (T), 2.06 (E) and 2.07 (S). The L/W ratios obtained were used for determination of grain shapes. The shapes determined were slender for the long type samples and bold for the short type samples. Density values were 1.43 g/ml (A), 1.48 g/ml (P), 1.45 g/ml (T), 1.46 g/ml (E) and 1.46 g/ml (S). Paste viscosity increased from out of scale (A), 12 cm (P), 11.5 cm (T), 5.50 cm (S) to 4.50 cm (E).1000 kernel weight values were 16.67 g (A), 14.53 g (P), 18.89 g (T), 18.47 g (E) and 18.32 (S). Broken ratios obtained were 3.62 (A), 0.31 (P), 1.58 (T), 6.39 (E) and 6.54 (S). Also investigations showed that rice grains contained 8.6%-10.9% moisture, 0.3%-0.6%, ash, 0.22-0.48% fiber, 6.2%- 8.0% protein, and 0.5%-1.0 % oil. Cooking reduced the starch percentages from 59.82%-64.27% to the range of 43.97%-55.47% for both types. For all types of rice amylose seems to be lower (24.00%-31.50%) than amylopectin (31.66%-39.57%). Cooking reduced both amylose (13.83%-18.67%) and amylopectin (26.30%-34.32%) content, however, it increased the amylopectin content (39.64%) of the Sudanese, S sample. Alkali spreading values were 3 (A), 1-2 (P), 1-2 (T), 6-7(E) and 6-7 for (S) and their gelatinization temperature (G T) was classified as high - intermediate (70-74 C degree) for A, high G T (75-79 C degree) for P and T, while E and S were classified as having low G T (55-69 C degree). Gel consistency (GC) values were 86.00 mm, 41.67 mm, 43.67 mm, 28.33 mm and 22.00 mm for A, P, T, E and S respectively

  16. Physiochemical properties and cooking quality of long and short rice (Oryza sativa) grains

    Energy Technology Data Exchange (ETDEWEB)

    Elbashir, L T. M. [Department of Food Science and Technology, Faculty of Agriculture, University of Khartoum, Khartoum (Sudan)

    2005-01-01

    Five rice grain samples namely long (American (Parboiled rice), A; Pakistan, P and Thailand, T) and short (Egyptian, E and Sudanese, S) types were investigated for their physicochemical and cooking quality characteristics. Investigations showed that rice grain of the two types had a length of 6.73 mm (A), 7.49 mm (P), 7.05 mm (T), 5.46 mm (E) and 5.64 mm (S); width of 2.08 mm (A), 1.73 mm (P), 2.06 mm (T), 2.66 mm (E) and 2.73 mm (S); thickness of 1.59 mm (A), 1.50 mm (P), 1.67 mm (T), 1.93 mm (E) and 1.83 mm (S) and length/width (L/w) ratio 3.24 (A), 4.35(P), 3.43 (T), 2.06 (E) and 2.07 (S). The L/W ratios obtained were used for determination of grain shapes. The shapes determined were slender for the long type samples and bold for the short type samples. Density values were 1.43 g/ml (A), 1.48 g/ml (P), 1.45 g/ml (T), 1.46 g/ml (E) and 1.46 g/ml (S). Paste viscosity increased from out of scale (A), 12 cm (P), 11.5 cm (T), 5.50 cm (S) to 4.50 cm (E).1000 kernel weight values were 16.67 g (A), 14.53 g (P), 18.89 g (T), 18.47 g (E) and 18.32 (S). Broken ratios obtained were 3.62 (A), 0.31 (P), 1.58 (T), 6.39 (E) and 6.54 (S). Also investigations showed that rice grains contained 8.6%-10.9% moisture, 0.3%-0.6%, ash, 0.22-0.48% fiber, 6.2%- 8.0% protein, and 0.5%-1.0 % oil. Cooking reduced the starch percentages from 59.82%-64.27% to the range of 43.97%-55.47% for both types. For all types of rice amylose seems to be lower (24.00%-31.50%) than amylopectin (31.66%-39.57%). Cooking reduced both amylose (13.83%-18.67%) and amylopectin (26.30%-34.32%) content, however, it increased the amylopectin content (39.64%) of the Sudanese, S sample. Alkali spreading values were 3 (A), 1-2 (P), 1-2 (T), 6-7(E) and 6-7 for