WorldWideScience

Sample records for asian cultivated rice

  1. Massive gene losses in Asian cultivated rice unveiled by comparative genome analysis

    Directory of Open Access Journals (Sweden)

    Itoh Takeshi

    2010-02-01

    Full Text Available Abstract Background Rice is one of the most important food crops in the world. With increasing world demand for food crops, there is an urgent need to develop new cultivars that have enhanced performance with regard to yield, disease resistance, and so on. Wild rice is expected to provide useful genetic resources that could improve the present cultivated species. However, the quantity and quality of these unexplored resources remain unclear. Recent accumulation of the genomic information of both cultivated and wild rice species allows for their comparison at the molecular level. Here, we compared the genome sequence of Oryza sativa ssp. japonica with sets of bacterial artificial chromosome end sequences (BESs from two wild rice species, O. rufipogon and O. nivara, and an African rice species, O. glaberrima. Results We found that about four to five percent of the BESs of the two wild rice species and about seven percent of the African rice could not be mapped to the japonica genome, suggesting that a substantial number of genes have been lost in the japonica rice lineage; however, their close relatives still possess their counterpart genes. We estimated that during evolution, O. sativa has lost at least one thousand genes that are still preserved in the genomes of the other species. In addition, our BLASTX searches against the non-redundant protein sequence database showed that disease resistance-related proteins were significantly overrepresented in the close relative-specific genomic portions. In total, 235 unmapped BESs of the three relatives matched 83 non-redundant proteins that contained a disease resistance protein domain, most of which corresponded to an NBS-LRR domain. Conclusion We found that the O. sativa lineage appears to have recently experienced massive gene losses following divergence from its wild ancestor. Our results imply that the domestication process accelerated large-scale genomic deletions in the lineage of Asian

  2. Loss of function at RAE2, a previously unidentified EPFL, is required for awnlessness in cultivated Asian rice.

    Science.gov (United States)

    Bessho-Uehara, Kanako; Wang, Diane R; Furuta, Tomoyuki; Minami, Anzu; Nagai, Keisuke; Gamuyao, Rico; Asano, Kenji; Angeles-Shim, Rosalyn B; Shimizu, Yoshihiro; Ayano, Madoka; Komeda, Norio; Doi, Kazuyuki; Miura, Kotaro; Toda, Yosuke; Kinoshita, Toshinori; Okuda, Satohiro; Higashiyama, Tetsuya; Nomoto, Mika; Tada, Yasuomi; Shinohara, Hidefumi; Matsubayashi, Yoshikatsu; Greenberg, Anthony; Wu, Jianzhong; Yasui, Hideshi; Yoshimura, Atsushi; Mori, Hitoshi; McCouch, Susan R; Ashikari, Motoyuki

    2016-08-01

    Domestication of crops based on artificial selection has contributed numerous beneficial traits for agriculture. Wild characteristics such as red pericarp and seed shattering were lost in both Asian (Oryza sativa) and African (Oryza glaberrima) cultivated rice species as a result of human selection on common genes. Awnedness, in contrast, is a trait that has been lost in both cultivated species due to selection on different sets of genes. In a previous report, we revealed that at least three loci regulate awn development in rice; however, the molecular mechanism underlying awnlessness remains unknown. Here we isolate and characterize a previously unidentified EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family member named REGULATOR OF AWN ELONGATION 2 (RAE2) and identify one of its requisite processing enzymes, SUBTILISIN-LIKE PROTEASE 1 (SLP1). The RAE2 precursor is specifically cleaved by SLP1 in the rice spikelet, where the mature RAE2 peptide subsequently induces awn elongation. Analysis of RAE2 sequence diversity identified a highly variable GC-rich region harboring multiple independent mutations underlying protein-length variation that disrupt the function of the RAE2 protein and condition the awnless phenotype in Asian rice. Cultivated African rice, on the other hand, retained the functional RAE2 allele despite its awnless phenotype. Our findings illuminate the molecular function of RAE2 in awn development and shed light on the independent domestication histories of Asian and African cultivated rice. PMID:27466405

  3. The archaeobotany of Asian rice expansion and the development of wet-field cultivation

    Science.gov (United States)

    Fuller, D.

    2008-12-01

    Archaeobotanical evidence provides direct data on past human diet and agriculture, including a geographical and chronological framework for studying the expansion of rice agriculture. The growth of systematic archaeobotanical sampling in recent years has allowed for the past presence of rice to be seen in relation to cultivation of other crops and associated weeds. The weed flora provides a basis for inferring the nature of cultivation systems, whether rain-fed dry rice or wetland "paddy" rice, a key distinction for considerations of past methane production. Nevertheless, current data is very unevenly distributed. This poster will summarize available evidence for the origins and spread of rice in South Asia (India and Pakistan), and mainland and Island Southeast Asia deriving from an earlier Chinese domestication. Where possible, such as in India or China, the potential of the weed flora remains for distinguishing wetland rice crops will be summarized. In broad terms, although the origins of rice use and cultivation begins by or during the Middle Holocene (6000- 3000 BC), rice cultivation spread outside the regions of the wild progenitor after this time. Two phases of rice expansion can be distinguished. Phase 1, between 3000 and 1500 BC, introduced rice to Southeast Asia, probably under wetland cultivation, and the spread of dry rice over northern India and Pakistan. Phase 2, taking place between 1000 and 0 BC, sees the spread of rice throughout the Southern Indian Peninsula, with weed evidence suggesting irrigated wetland rice. Similarly, this period sees the spread of intensive paddy agriculture through Korea and Japan, but in Southeast Asia is probably related to a spread of rice in upland, dry field systems.

  4. Comparison of Cheng's Index-and SSR Marker-based Classification of Asian Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    WANG Cai-hong; XU Qun; YU Ping; YUAN Xiao-ping; YU Han-yong; WANG Yi-ping; TANG Sheng-xiang

    2013-01-01

    A total of 100 cultivated rice accessions,with a clear isozyme-based classification,were analyzed based on Cheng's index and simple sequence repeat (SSR) marker.The results showed that the isozyme-based classification was in high accordance with that based on Cheng's index and SSR markers.Mantel-test revealed that the Euclidean distance of Cheng's index was significantly correlated with Nei's unbiased genetic distance of SSR markers (r =0.466,P ≤ 0.01).According to the model-based group and cluster analysis,the Cheng's index-and SSR-based classification coincided with each other,with the goodness of fit of 82.1% and 84.7% in indica,97.4% and 95.1% in japonica,respectively,showing higher accordance than that within subspecies.Therefore,Cheng's index could be used to classify subspecies,while SSR marker could be more efficient to analyze the subgroups within subspecies.

  5. Elemental Content in Brown Rice by Inductively Coupled Plasma Atomic Emission Spectroscopy Reveals the Evolution of Asian Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    Yawen Zeng; Luxiang Wang; Juan Du; Jiafu Liu; Shuming Yang; Xiaoying Pu; Fenghui Xiao

    2009-01-01

    The phylogenetic relationship for classification traits and eight mineral elements in brown rice (Oryza sativa L.) from Yunnan Province in China was carried out using microwave assisted digestion followed by inductively coupled plasma atomic emission spectroscopy, and the analytical procedures were carefully controlled and validated. In general, the results show that the mean levels of K, Ca, Mg, Fe and Cu in brown rice for 789 accessions of rice landraces was distinctly lower than that of improved cultivars. They further demonstrate that Ca plays an important role in the differentiation of subspecies indica-japonica, especially to enhance adaptation of cold stress, and that five mineral elements in brown rice enhance the eurytopicity from landrace to improved cultivar. Hierarchical cluster analysis, using average linkage from SPSS software based on eight mineral elements in brown rice, showed that Yunnan rice could be grouped into rice landrace and improved cultivar, with the rice landrace being further clustered into five subgroups, and that, interestingly, purple rice does not cluster with either of the groups. Our present data confirm that indica is the closest relative of late rice and white rice, and that they constitute rice landraces together, whereas japonica is the closest relatives of non-nuda, early-mid and glutinous rice. It is further shown that japonica, non-nuda, early-mid, glutinous, white and red rice might be more primitive than indica, nuda, late, non-glutinous and purple rice, respectively.

  6. Patterns of sequence divergence and evolution of the S orthologous regions between Asian and African cultivated rice species.

    Science.gov (United States)

    Guyot, Romain; Garavito, Andrea; Gavory, Frédérick; Samain, Sylvie; Tohme, Joe; Ghesquière, Alain; Lorieux, Mathias

    2011-01-01

    A strong postzygotic reproductive barrier separates the recently diverged Asian and African cultivated rice species, Oryza sativa and O. glaberrima. Recently a model of genetic incompatibilities between three adjacent loci: S(1)A, S(1) and S(1)B (called together the S(1) regions) interacting epistatically, was postulated to cause the allelic elimination of female gametes in interspecific hybrids. Two candidate factors for the S(1) locus (including a putative F-box gene) were proposed, but candidates for S(1)A and S(1)B remained undetermined. Here, to better understand the basis of the evolution of regions involved in reproductive isolation, we studied the genic and structural changes accumulated in the S(1) regions between orthologous sequences. First, we established an 813 kb genomic sequence in O. glaberrima, covering completely the S(1)A, S(1) and the majority of the S(1)B regions, and compared it with the orthologous regions of O. sativa. An overall strong structural conservation was observed, with the exception of three isolated regions of disturbed collinearity: (1) a local invasion of transposable elements around a putative F-box gene within S(1), (2) the multiple duplication and subsequent divergence of the same F-box gene within S(1)A, (3) an interspecific chromosomal inversion in S(1)B, which restricts recombination in our O. sativa×O. glaberrima crosses. Beside these few structural variations, a uniform conservative pattern of coding sequence divergence was found all along the S(1) regions. Hence, the S(1) regions have undergone no drastic variation in their recent divergence and evolution between O. sativa and O. glaberrima, suggesting that a small accumulation of genic changes, following a Bateson-Dobzhansky-Muller (BDM) model, might be involved in the establishment of the sterility barrier. In this context, genetic incompatibilities involving the duplicated F-box genes as putative candidates, and a possible strengthening step involving the

  7. Patterns of Sequence Divergence and Evolution of the S1 Orthologous Regions between Asian and African Cultivated Rice Species

    Science.gov (United States)

    Gavory, Frédérick; Samain, Sylvie; Tohme, Joe; Ghesquière, Alain; Lorieux, Mathias

    2011-01-01

    A strong postzygotic reproductive barrier separates the recently diverged Asian and African cultivated rice species, Oryza sativa and O. glaberrima. Recently a model of genetic incompatibilities between three adjacent loci: S1A, S1 and S1B (called together the S1 regions) interacting epistatically, was postulated to cause the allelic elimination of female gametes in interspecific hybrids. Two candidate factors for the S1 locus (including a putative F-box gene) were proposed, but candidates for S1A and S1B remained undetermined. Here, to better understand the basis of the evolution of regions involved in reproductive isolation, we studied the genic and structural changes accumulated in the S1 regions between orthologous sequences. First, we established an 813 kb genomic sequence in O. glaberrima, covering completely the S1A, S1 and the majority of the S1B regions, and compared it with the orthologous regions of O. sativa. An overall strong structural conservation was observed, with the exception of three isolated regions of disturbed collinearity: (1) a local invasion of transposable elements around a putative F-box gene within S1, (2) the multiple duplication and subsequent divergence of the same F-box gene within S1A, (3) an interspecific chromosomal inversion in S1B, which restricts recombination in our O. sativa×O. glaberrima crosses. Beside these few structural variations, a uniform conservative pattern of coding sequence divergence was found all along the S1 regions. Hence, the S1 regions have undergone no drastic variation in their recent divergence and evolution between O. sativa and O. glaberrima, suggesting that a small accumulation of genic changes, following a Bateson-Dobzhansky-Muller (BDM) model, might be involved in the establishment of the sterility barrier. In this context, genetic incompatibilities involving the duplicated F-box genes as putative candidates, and a possible strengthening step involving the chromosomal inversion might participate to

  8. Patterns of sequence divergence and evolution of the S orthologous regions between Asian and African cultivated rice species.

    Directory of Open Access Journals (Sweden)

    Romain Guyot

    Full Text Available A strong postzygotic reproductive barrier separates the recently diverged Asian and African cultivated rice species, Oryza sativa and O. glaberrima. Recently a model of genetic incompatibilities between three adjacent loci: S(1A, S(1 and S(1B (called together the S(1 regions interacting epistatically, was postulated to cause the allelic elimination of female gametes in interspecific hybrids. Two candidate factors for the S(1 locus (including a putative F-box gene were proposed, but candidates for S(1A and S(1B remained undetermined. Here, to better understand the basis of the evolution of regions involved in reproductive isolation, we studied the genic and structural changes accumulated in the S(1 regions between orthologous sequences. First, we established an 813 kb genomic sequence in O. glaberrima, covering completely the S(1A, S(1 and the majority of the S(1B regions, and compared it with the orthologous regions of O. sativa. An overall strong structural conservation was observed, with the exception of three isolated regions of disturbed collinearity: (1 a local invasion of transposable elements around a putative F-box gene within S(1, (2 the multiple duplication and subsequent divergence of the same F-box gene within S(1A, (3 an interspecific chromosomal inversion in S(1B, which restricts recombination in our O. sativa×O. glaberrima crosses. Beside these few structural variations, a uniform conservative pattern of coding sequence divergence was found all along the S(1 regions. Hence, the S(1 regions have undergone no drastic variation in their recent divergence and evolution between O. sativa and O. glaberrima, suggesting that a small accumulation of genic changes, following a Bateson-Dobzhansky-Muller (BDM model, might be involved in the establishment of the sterility barrier. In this context, genetic incompatibilities involving the duplicated F-box genes as putative candidates, and a possible strengthening step involving the chromosomal

  9. [Major domestication traits in Asian rice].

    Science.gov (United States)

    Ou, Shu-Jun; Wang, Hong-Ru; Chu, Cheng-Cai

    2012-11-01

    Rice (Oryza sativa L.) is an excellent model plant in elucidation of cereal domestication. Loss of seed shattering, weakened dormancy, and changes in plant architecture were thought to be three key events in the rice domestication and creating the high-yield, uniform-germinating, and densely-planting modern rice. Loss of shattering is considered to be the direct morphological evidence for identifying domesticated rice. Two major shattering QTLs, Sh4 and qSH1, have displayed different domestication histories. Weakened seed dormancy is essential for synchronous germination in agricultural production. Genes Sdr4, qSD7-1, and qSD12 impose a global and complementary adaptation strategies in controlling seed dormancy. The prostate growth habit of wild rice is an adaptation to disturbed habitats, while the erect growth habit of rice cultivars meet the needs of compact planting, and such a plant architecture is mainly controlled by PROG1. The outcrossing habit of wild rice promotes propagation of domestication genes among different populations, while the self-pollinating habit of cultivated rice facilitates fixation of domestication genes. Currently, the researches on rice domestication mainly focus on individual genes or multiple neutral markers, and much less attention has been paid to the evolution of network controlling domestication traits. With the progress in functional genomics research, the molecular mechanism of domestication traits is emerging. Rice domestication researches based on network will be more comprehensive and better reflect rice domestica-tion process. Here, we reviewed most progresses in molecular mechanisms of rice domestication traits, in order to provide the new insights for rice domestication and molecular breeding.

  10. The Origin of Flooded Rice Cultivation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Rice cultivation has long been considered to have originated from seeding of annual types of wild ricesomewhere in subtropics, tropics or in the Yangtze River basin. That idea, however, contains a fatally weak point, when we consider the tremendous difficulty for primitive human to seed any cereal crop in the warm and humid climate, where weed thrives all year round. Instead of the accepted theory, we have to see a reality that vegetative propagation of edible plants is a dominant form of agriculture in such regions. The possibility is discussed that Job's tears and rice, two cereal crops unique to the region, might have been developed via vegetative propagation to obtain materials for medicine or herb tea in backyard gardens prior to cereal production. This idea is supported by the fact that rice in temperate regions is still perennial in its growth habit and that such backyard gardens with transplanted taro can still be seen from Yunnan Province of China to Laos. Thanks to detailed survey of wild rice throughout China for 1970-1980, it is now confirmed that a set of clones of wild rice exist in shallow swamps in Jiangxi Province, an area with severe winter cold. In early summer ancient farmers may have divided the sprouting buds and spread them by transplanting into flooded shallow marsh. Such way of propagation might have faster improved less productive rice through a better genetic potential for response to human interference than quick fixation in seed propagation, because vegetative parts are heterogeneous. Obviously, such a primitive manner of rice cultivation did include the essential parts of rice farming, i.e., nursery bed, transplanting in flooded field of shallow marsh like. Transfer from the primitive nursery to true nursery by seed may have later allowed rice cultivation to be extended to northern regions. In thus devised flooded cultivation there were a series of unique advantages, i.e.; continuous cropping of rice in a same plot, no soil erosion

  11. Single-base resolution maps of cultivated and wild rice methylomes and regulatory roles of DNA methylation in plant gene expression

    DEFF Research Database (Denmark)

    Li, Xin; Zhu, Jingde; Hu, Fengyi;

    2012-01-01

    DNA methylation plays important biological roles in plants and animals. To examine the rice genomic methylation landscape and assess its functional significance, we generated single-base resolution DNA methylome maps for Asian cultivated rice Oryza sativa ssp. japonica, indica and their wild...

  12. Environmental profile of paddy rice cultivation with different straw management.

    Science.gov (United States)

    Fusi, Alessandra; Bacenetti, Jacopo; González-García, Sara; Vercesi, Annamaria; Bocchi, Stefano; Fiala, Marco

    2014-10-01

    Italy is the most important European country in terms of paddy rice production. North Italian districts such as Vercelli, Pavia, Novara, and Milano are known as some of the world's most advanced rice cultivation sites. In 2013 Italian rice cultivation represented about 50% of all European rice production by area, and paddy fields extended for over 216,000 ha. Cultivation of rice involves different agricultural activities which have environmental impacts mainly due to fossil fuels and agrochemical requirements as well as the methane emission associated with the fermentation of organic material in the flooded rice fields. In order to assess the environmental consequences of rice production in the District of Vercelli, the cultivation practices most frequently carried out were inventoried and evaluated. The general approach of this study was not only to gather the inventory data for rice production and quantify their environmental impacts, but also to identify the key environmental factors where special attention must be paid. Life Cycle Assessment methodology was applied in this study from a cradle-to-farm gate perspective. The environmental profile was analyzed in terms of seven different impact categories: climate change, ozone depletion, human toxicity, terrestrial acidification, freshwater eutrophication, marine eutrophication, and fossil depletion. Regarding straw management, two different scenarios (burial into the soil of the straw versus harvesting) were compared. The analysis showed that the environmental impact was mainly due to field emissions, the fuel consumption needed for the mechanization of field operations, and the drying of the paddy rice. The comparison between the two scenarios highlighted that the collection of the straw improves the environmental performance of rice production except that for freshwater eutrophication. To improve the environmental performance of rice production, solutions to save fossil fuel and reduce the emissions from

  13. Farmers acquire skills in paddy rice cultivation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Huye- A joint initiative that brings Rwanda and China to deepen technology transfer into the economy within agriculture has embarked on training rice farmers for the purposes of boosting rice production. China-Rwanda Agriculture Technology Demonstration Center (RATDC) has trained 43 rice farmers in agricultural technology as a way of helping them improve their productivity.

  14. Effect of Rice Cultivation in the South of China on Hunan Civilization

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Ancient cultivated rice: important archaeological findings Rice, a crop cultivated by man with long history, is the staple food on which half of the world population lives. When and where did rice farming originate? Is rice in China an indigenous plant or the one introduced from abroad? Different opinions have been held for over one hundred years. People once thought that rice was firstly cultivated in India, afterwards introduced into China and Southeast Asia from South Asia.

  15. Comparative Study of Rice Morphogenesis wit Different Cultivation Methods

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characteristics of different rice culti- vars. [Method] Based on continuous field observation and destructive sampling over a growing season, detailed organ morphological data were obtained including leaf length, node number, plant height, tiller number, leaf angle, leaf area and specific leaf weight, to compare organ morphological differences among 4 rice cultivars of Baidao (indica), Jinnanfeng (japonica), 9325 (japonica) and 9915 (japonica) with 3 cultivation methods of field planting in Weigang, pot planting in Weigang, and field planting in Jiangpu. [Result] Maximum leaf length of each node gradually increased at the early growth stage and decreased at the later growth stage, the relationship between maximum leaf length and node position can be described by the equations y=a,,-~ and y=ax+b; node number, growth duration, leaf length and plant height of pot planting rice in Weigang were smaller than that of the other two field planting meth- ods; the relationship between plant height and sunshine duration, plant height and GDD (growing degree days) can be described by the equation y=ax+b, 19.23 ℃.d of GDD (≥10 ≥-d) and 8.12 h of sunshine duration were required to increase 1 cm of plant height; plant height, tiller number, and leaf area of Baidao were higher than that of the other 3 laponica rice cultivars, but the specific leaf weight and leaf angle were smaller. [Conclusion] Comparison of morphological characteristic differ- ences among rice cultivars is an important way to select water-saving and drought- tolerant rice varieties. In this study, the experimental results can be integrated into a rice functional-architectural model to simulate rice organ growth dynamics in a three- dimensional space, thereby providing reference for selecting water

  16. Single-base resolution maps of cultivated and wild rice methylomes and regulatory roles of DNA methylation in plant gene expression

    Directory of Open Access Journals (Sweden)

    Li Xin

    2012-07-01

    Full Text Available Abstract Background DNA methylation plays important biological roles in plants and animals. To examine the rice genomic methylation landscape and assess its functional significance, we generated single-base resolution DNA methylome maps for Asian cultivated rice Oryza sativa ssp. japonica, indica and their wild relatives, Oryza rufipogon and Oryza nivara. Results The overall methylation level of rice genomes is four times higher than that of Arabidopsis. Consistent with the results reported for Arabidopsis, methylation in promoters represses gene expression while gene-body methylation generally appears to be positively associated with gene expression. Interestingly, we discovered that methylation in gene transcriptional termination regions (TTRs can significantly repress gene expression, and the effect is even stronger than that of promoter methylation. Through integrated analysis of genomic, DNA methylomic and transcriptomic differences between cultivated and wild rice, we found that primary DNA sequence divergence is the major determinant of methylational differences at the whole genome level, but DNA methylational difference alone can only account for limited gene expression variation between the cultivated and wild rice. Furthermore, we identified a number of genes with significant difference in methylation level between the wild and cultivated rice. Conclusions The single-base resolution methylomes of rice obtained in this study have not only broadened our understanding of the mechanism and function of DNA methylation in plant genomes, but also provided valuable data for future studies of rice epigenetics and the epigenetic differentiation between wild and cultivated rice.

  17. Rice cultivation in the farming systems of Sukumaland, Tanzania

    NARCIS (Netherlands)

    Meertens, H.C.C.

    1999-01-01

    This thesis investigates options for sustainable rice cultivation and general agricultural development in the Mwanza and Shinyanga regions in northwestern Tanzania, often called Sukumaland due to the predominance of Wasukuma people. Generally Sukumaland has a semi-arid climate; agriculture is constr

  18. 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.

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

    Science.gov (United States)

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

    2016-01-01

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

  20. Rice cultivation in the farming systems of Sukumaland, Tanzania

    OpenAIRE

    Meertens, H.C.C.

    1999-01-01

    This thesis investigates options for sustainable rice cultivation and general agricultural development in the Mwanza and Shinyanga regions in northwestern Tanzania, often called Sukumaland due to the predominance of Wasukuma people. Generally Sukumaland has a semi-arid climate; agriculture is constrained by unreliable and low rainfall. In the past fifty years the population density has doubled in most parts. This has triggered several changes in farming systems. One important change is a redu...

  1. Deciphering Community Structure of Methanotrophs Dwelling in Rice Rhizospheres of an Indian Rice Field Using Cultivation and Cultivation-Independent Approaches.

    Science.gov (United States)

    Pandit, Pranitha S; Rahalkar, Monali C; Dhakephalkar, Prashant K; Ranade, Dilip R; Pore, Soham; Arora, Preeti; Kapse, Neelam

    2016-04-01

    Methanotrophs play a crucial role in filtering out methane from habitats, such as flooded rice fields. India has the largest area under rice cultivation in the world; however, to the best of our knowledge, methanotrophs have not been isolated and characterized from Indian rice fields. A cultivation strategy composing of a modified medium, longer incubation time, and serial dilutions in microtiter plates was used to cultivate methanotrophs from a rice rhizosphere sample from a flooded rice field in Western India. We compared the cultured members with the uncultured community as revealed by three culture-independent methods. A novel type Ia methanotroph (Sn10-6), at the rank of a genus, and a putative novel species of a type II methanotroph (Sn-Cys) were cultivated from the terminal positive dilution (10(-6)). From lower dilution (10(-4)), a strain of Methylomonas spp. was cultivated. All the three culture-independent analyses, i.e., pmoA clone library, terminal restriction fragment length polymorphism (T-RFLP), and metagenomics approach, revealed the dominance of type I methanotrophs. Only metagenomic analysis showed significant presence of type II methanotrophs, albeit in lower proportion (37 %). All the three isolates showed relevance to the methanotrophic community as depicted by uncultured methods; however, the cultivated members might not be the most dominant ones. In conclusion, a combined cultivation and cultivation-independent strategy yielded us a broader picture of the methanotrophic community from rice rhizospheres of a flooded rice field in India. PMID:26547567

  2. POTENTIAL PRODUCTIVITY OF MODERN RICE TECHNOLOGY AND REASONS FOR LOW PRODUCTIVITY ON ASIAN RICE FARMS

    OpenAIRE

    Herdt, Robert W.

    1981-01-01

    Results of a collaborative project involving over 28 agronomists and economists are reported. Over 800 agronomic experiments conducted in ten locations in six Asian countries comparing farmers' production with maximum yield levels of modern rice technology are analysed. Under wet season conditions, yields were raised by an average of 0.9 tonnes per hectare, but the cost of obtaining the increased yields exceeded their value in six out of ten locations. Under dry season conditions, yields were...

  3. Genetic Diversity Based on Allozyme Alleles of Chinese Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    TANG Sheng-xiang; WEI Xing-hua; JIANG Yun-zhu; D S Brar; G S Khush

    2007-01-01

    Genetic diversity was analyzed with 6 632 core rice cultivars selected from 60 282 Chinese rice accessions on the basis of 12 allozyme loci, Pgil, Pgi2, Ampl, Amp2, Amp3, Amp4, Sdh1, Adh1, Est1, Est2, Est5 and Est9, by starch gel electrophoresis. Among the materials examined, 52 alleles at 12 polymorphic loci were identified, which occupied 96.3% of 54 alleles found in cultivated germplasm of O.sativa L. The number of alleles per locus ranged from 2 to 7 with an average of 4.33. The gene diversity (He) each locus varied considerably from 0.017 for Amp4 to 0.583 for Est2 with an average gene diversity (Ht) 0.271, and Shannon-Wiener index from 0.055 to 0.946 with an average of 0.468. The degree of polymorphism (DP) was in a range from 0.9 to 46.9% with an average of 21.4%. It was found that the genetic diversity in japonica (Keng) subspecies was lower in terms of allele's number, Ht and S-W index, being 91.8, 66.2 and 75.7% of indica (Hsien) one, respectively. Significant genetic differentiation between indica and japonica rice has been appeared in the loci Pgil, Amp2, Pgi2, and Est2, with higher average coefficient of genetic differentiation (Gst) 0.635, 0.626, 0.322 and 0.282, respectively. Except less allele number per locus (3.33) for modern cultivars, being 76.9% of landraces, the Ht and S-W index showed in similar between the modern cultivars and the landraces detected. In terms of allozyme, the rice cultivars in the Southwest Plateau and Central China have richer genetic diversity. The present study reveals again that Chinese cultivated rice germplasm has rich genetic diversity, showed by the allozyme allele variation.

  4. Appraising Rice Production Efficiency in Taiwan under the Contract Cultivation System

    OpenAIRE

    Lo, Ming-Che; Hwang, Tsorng-Chi

    1992-01-01

    The popularly accepted rice production system in Taiwan is contract cultivation. This paper investigates the production efficiency of rice farming under the contract cultivation system. Data obtained from the financial accounts of 60 rice-farming families are used and estimated in a translog cost function. The efficiency indicators are the elasticities of input demand combinations with respsect to own and cross-input prices and the average incremental cost. The results show that contract labo...

  5. Much Improved Water Use Efficiency of Rice under Non-Flooded Mulching Cultivation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Water shortage is increasingly limiting the luxury use of water in rice cultivation. In this study, non-flooded mulching cultivation of rice only consumed a fraction of the water that was needed for traditional flooded cultivation and largely maintained the grain yield. We also investigated the growth and development of rice plants and examined grain yield formation when rice was subjected to non-flooded mulching cultivation. One indica hybrid rice combination was grown in a field experiment and three cultivation methods, traditional flooding (TF), non-flooded straw mulching cultivation (SM) and non-flooded plastic mulching cultivation (PM), were conducted during the whole season. Grain yield showed that there was no significant difference between SM and TF rice, but the grain yield of SM cultivation was significantly higher than that of PM. The tiller numbers were inhibited in the early stage under non-flooded mulching cultivation, but the situation was reversed at the later period. Both SM and PM rice reduced dry matter accumulation of shoot, but increased root dry weight,enhanced the remobilization of assimilates from stems to grains and increased the harvest index. During the middle and later grain filling period, mulched plants showed a faster decrease in chlorophyll concentrations, photosynthetic rates of flag leaves and root activity than TF rice, indicating that non-flooded mulching cultivation enhanced plant senescence. In comparison, SM treatment produced higher grain yield and, more dry matter accumulation and panicle numbers than the PM treatment. The overall results suggest that high yield of non-flooded mulching cultivation of rice can be achieved with much improved irrigational water use efficiency.

  6. Changes in soil microbial properties and nematode assemblage over time during rice cultivation

    Directory of Open Access Journals (Sweden)

    Yudi Liu

    2013-05-01

    Full Text Available The properties of red soil may change over time when paddy fields are developed on what was previously dry land. The effect of rice cultivation duration on soil invertebrates is unknown. Five chronosequences of rice cultivation (1, 10, 20, 50 and 100 years were selected to investigate the temporal changes of soil microbiological properties and nematode assemblages. The results showed that soil microbial properties (microbial biomass C, microbial biomass N, basal respiration, nutrient availability (mineral N and P, nematode abundance and richness of nematode genera generally increased with the duration of rice cultivation. Notably, most soil measurements peaked after 50 years of cultivation (P<0.05 and decreased slightly after 100 years. As the period of rice cultivation increased, the proportion of nematode herbivores rose significantly (P < 0.05, while that of predators/omnivores slightly declined. Nematode Channel Ratio (NCR also increased with cultivation duration (P < 0.05, indicating that the bacterial energy channel was more dominant in old rice fields when compared to those cultivated for a shorter period. Other ecological indices of nematode assemblage such as maturity index and structure index, did not reveal consistent trends with an increased period of rice cultivation. In summary, a change in land use from dry land to paddy fields promotes soil microbial properties and nematode assemblages in the first few decades, which then become stable after 50 years of cultivation.

  7. Modelling the Geographical Origin of Rice Cultivation in Asia Using the Rice Archaeological Database.

    Directory of Open Access Journals (Sweden)

    Fabio Silva

    Full Text Available We have compiled an extensive database of archaeological evidence for rice across Asia, including 400 sites from mainland East Asia, Southeast Asia and South Asia. This dataset is used to compare several models for the geographical origins of rice cultivation and infer the most likely region(s for its origins and subsequent outward diffusion. The approach is based on regression modelling wherein goodness of fit is obtained from power law quantile regressions of the archaeologically inferred age versus a least-cost distance from the putative origin(s. The Fast Marching method is used to estimate the least-cost distances based on simple geographical features. The origin region that best fits the archaeobotanical data is also compared to other hypothetical geographical origins derived from the literature, including from genetics, archaeology and historical linguistics. The model that best fits all available archaeological evidence is a dual origin model with two centres for the cultivation and dispersal of rice focused on the Middle Yangtze and the Lower Yangtze valleys.

  8. Declining Labour Use in Agriculture : A Case of Rice Cultivation in Andhra Pradesh

    OpenAIRE

    Duvvuru, Narasimha Reddy; Motkuri, Venkatanarayana

    2013-01-01

    The present paper examines the changing nature of labour use in rice cultivation in Andhra Pradesh. The study observed that there is a fast decline in labour use in respect of rice cultivation in Andhra Pradesh. All three forms of labour (family, casual and attached) have followed the same trend. But the share of casual labour in the total labour used in rice cultivation is increasing with a corresponding decline in the share of family labour. By gender, although both male and female labour u...

  9. Characteristics of Channeling Flow in Cultivated Horizon of Saline Rice Soil

    Institute of Scientific and Technical Information of China (English)

    LUO Jinming; DENG Wei; ZHANG Xiaoping; YANG Fan; LI Xiujun

    2006-01-01

    By applying bromide ion as tracer, the channeling flow has been quantitatively described in saline rice soil and alkaline soil of Da'an City, Jilin Province of China. Breakthrough curves of bromide ion in the saline rice soils after 1-year cultivation and 5-year cultivation and alkaline soil have been attained. Results show that the rice cultivation practice can improve the alkaline soil structure, however, it can accelerate the development of channeling flow pathway.Therefore, the channeling flow pathway has been developed widely in saline rice soil, but rarely in the alkaline soil.Three models of convection-dispersion equation (CDE), transfer functional model (TFM) and Back-Progation Network (BP Network) were used to simulate the transportation process of bromide ion. The peaks of probability density function of saline rice soil are higher with left skewed feature compared with that of the alkaline soil. It shows that the TFM and CDE can simulate the transportation process of the bromide ion in saline rice soil after 5-year cultivation, however, some deviation exists when it was used to simulate transportation process of bromide ion in saline rice soil after 1-year cultivation and alkaline soil; BP network can effectively simulate transportation process of bromide ion in both saline rice soil and alkaline soil.

  10. Little white lies: pericarp color provides insights into the origins and evolution of Southeast Asian weedy rice

    Science.gov (United States)

    Weedy rice is a conspecific form of cultivated rice (Oryza sativa L.) that infests rice fields and results in severe crop losses. Weed strains in different world regions appear to have originated multiple times from different domesticated and/or wild rice progenitors. In the case of Malaysian weedy ...

  11. The discovery of an Est locus related to the origin, evolution and classification of Asian rice

    Institute of Scientific and Technical Information of China (English)

    WANGXiangkun; CAIHongwei; LIZhichao; CHENGKansheng; ZHANGYaozhong

    1992-01-01

    In the isozyme studies concerning the origin and evolution of Asian rice, Morishima(1990) pointed out that, so far, there have been about 20 isozyme loci related to the differentiation of indica and japonica. In 1990, we discovered another Est locus related to the origin, evolution and classification of Asian rive. Genetic studies revealed that there were 5 multiple alleles on this locus represented 4 isozyme bands,

  12. Effects of Bt-transgenic rice cultivation on planktonic communities in paddy fields and adjacent ditches.

    Science.gov (United States)

    Liu, Yongbo; Liu, Fang; Wang, Chao; Quan, Zhanjun; Li, Junsheng

    2016-09-15

    The non-target effects of transgenic plants are issues of concern; however, their impacts in cultivated agricultural fields and adjacent natural aquatic ecosystems are poorly understood. We conducted field experiments during two growing seasons to determine the effects of cultivating Bacillus thuringiensis (Bt)-transgenic rice on the phytoplankton and zooplankton communities in a paddy field and an adjacent ditch. Bt toxin was detected in soil but not in water. Water quality was not significantly different between non-Bt and Bt rice fields, but varied among up-, mid- and downstream locations in the ditch. Cultivation of Bt-transgenic rice had no effects on zooplankton communities. Phytoplankton abundance and biodiversity were not significantly different between transgenic and non-transgenic rice fields in 2013; however, phytoplankton were more abundant in the transgenic rice field than in the non-transgenic rice field in 2014. Water quality and rice type explained 65.9% and 12.8% of this difference in 2014, respectively. Phytoplankton and zooplankton were more abundant in mid- and downstream, than upstream, locations in the ditch, an effect that we attribute to water quality differences. Thus, the release of Bt toxins into field water during the cultivation of transgenic crops had no direct negative effects on plankton community composition, but indirect effects that alter environmental conditions should be taken into account during the processes of management planning and policymaking. PMID:27219503

  13. CURRENT STATUS AND POTENTIAL OF BIOTECHNOLOGICAL APPROACHES FOR RICE BLAST DISEASE IN THE RICE CULTIVATION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Petenko A. I.

    2014-09-01

    Full Text Available Rice blast caused by Pyricularia oryzae is a major disease affecting rice production grown in upland and wetland rice. Application of biotechnological approach to protect against the disease may be an alternative strategy to chemical control

  14. CURRENT STATUS AND POTENTIAL OF BIOTECHNOLOGICAL APPROACHES FOR RICE BLAST DISEASE IN THE RICE CULTIVATION TECHNOLOGY

    OpenAIRE

    Petenko A. I.; Volkova S. A.

    2014-01-01

    Rice blast caused by Pyricularia oryzae is a major disease affecting rice production grown in upland and wetland rice. Application of biotechnological approach to protect against the disease may be an alternative strategy to chemical control

  15. Role of Golden Apple Snail in Organic Rice Cultivation and Weed Management

    OpenAIRE

    R.C. Joshi; Martin, E. C.; Wada, T.; Sebastian, L. S.

    2005-01-01

    The Golden Apple Snail (GAS), Pomacea canaliculata (Lamarck), is a major pest of rice and other aquatic crops in many Asian farms. Farmers’ first line of defense is to use non-specific chemicals for “instant” kill of GAS, without considering its effect on their health, the environment, and non-target organisms. However, some organic rice farmers in Japan, Korea, and the Philippines do not kill GAS but manage them as bio-weeders in rice fields. We evaluated organic farmers’ innovation at the P...

  16. StudyandApplicationof¨ThreeHighandOneEnsuring¨Cultivation Mode of Double Cropping Rice

    Institute of Scientific and Technical Information of China (English)

    Chunrui PENG; Jinshui XIE; Caifei QIU; Yinfei QIAN; Xianjiao GUAN; Xiaohua PAN

    2012-01-01

    A set of "three high and one ensuring" cultivation mode of double cropping rice, the core of which was high panicle bearing tiller rate, high seed setting rate, high grain plumpness and ensuring high quality, was explored through many years of research. In this study, the effect of "three high and one ensuring" cultivation mode of double cropping rice was compared and investigated by field experiment and multiple location demonstration. The field experiment indicated that "three high and one ensuring" cultivation mode promoted the vegetative growth during early stage, inhibited the formation of ineffective tillers, promoted the growth of effective tillers and the formation of panicles, improved the panicle bearing tiller rate, in- creased the total number of spikelets, enhanced the seed setting rate and grain plumpness, increased the grain yield by 12.22%-19.73% at highly significant level, and improved the rice quality. Furthermore, the field demonstration also verified the results of field experiment.

  17. Fine mapping of a gene causing hybrid pollen sterility between Yunnan weedy rice and cultivated rice (Oryza sativa L.) and phylogenetic analysis of Yunnan weedy rice.

    Science.gov (United States)

    Wang, Yong; Zhong, Zheng Zheng; Zhao, Zhi Gang; Jiang, Ling; Bian, Xiao Feng; Zhang, Wen Wei; Liu, Ling Long; Ikehashi, H; Wan, Jian Min

    2010-02-01

    Weedy rice represents an important resource for rice improvement. The F(1) hybrid between the japonica wide compatibility rice cultivar 02428 and a weedy rice accession from Yunnan province (SW China) suffered from pollen sterility. Pollen abortion in the hybrid occurred at the early bicellular pollen stage, as a result of mitotic failure in the microspore, although the tapetum developed normally. Genetic mapping in a BC(1)F(1) population (02428//Yunnan weedy rice (YWR)/02428) showed that a major QTL for hybrid pollen sterility (qPS-1) was present on chromosome 1. qPS-1 was fine-mapped to a 110 kb region known to contain the hybrid pollen sterility gene Sa, making it likely that qPS-1 is either identical to, or allelic with Sa. Interestingly, F(1) hybrid indicated that Dular and IR36 were assumed to carry the sterility-neutral allele, Sa ( n ). Re-sequencing SaM and SaF, the two component genes present at Sa, suggested that variation for IR36 and Dular may be responsible for the loss of male sterility, and the qPS-1 sequence might be derived from wild rice or indica cultivars. A phylogenetic analysis based on microsatellite genotyping suggested that the YWR accession is more closely related to wild rice and indica type cultivars than to japonica types. Thus it is probable that the YWR accession evolved from a spontaneous hybrid between wild rice and an ancient cultivated strain of domesticated rice.

  18. From tidal wetland to paddy rice fields - Changes in soil microbial communities during 2000 years of rice cultivation

    Science.gov (United States)

    Bannert, Andrea; Kleineidam, Kristina; Frenzel, Peter; Ho, Adrian; Schloter, Michael

    2010-05-01

    In many areas of China tidal wetlands have been converted into agricultural land for lowland rice cultivation. However, the consequences and effects on soil microbial communities are poorly understood. Therefore, we investigated bacterial and archaeal communities involved in nitrification and denitrification based on diversity and abundance pattern of the corresponding functional genes in a tidal wetland and two paddy soils cultivated for 50 years respectively 2000 years with rice. The abundances of all measured genes increased from the tidal wetland to the 2000 years paddy soil in reference to one gram of soil due to a significant increase of the microbial biomass. When relating the functional gene copies to the extracted microbial biomass highest copy numbers were observed in the paddy soil with 50 years of rice cultivation history with exception of the archaeal nitrification gene amoA. T-RFLP data of the archaeal amoA gene and the bacterial denitrification gene nosZ revealed significant differences in community composition in the three investigated soils. Overall, our results indicate clear changes in abundance and diversity pattern of microbial communities participating in nitrogen cycling during rice paddy evolution.

  19. International rice trade and security stocks: Prospects for an expanded Asian international rice reserve:

    OpenAIRE

    Dorosh, Paul A.; Childs, Abigail

    2014-01-01

    This paper examines the recent experience with international rice reserves in Asia and re-examines the roles of national stocks and international trade in stabilizing domestic rice prices and availability in importing countries.

  20. Cultivation of irrigated-paddy rice with Azolla and Nila fish application

    OpenAIRE

    Kaimuddin; Ibrahim, Bachrul; Tangko, Lina

    2011-01-01

    This research aimed to find out effect of Azolla and Nila fish in cultivation of irrigated- paddy rice to increase rice production, and to find out reduction of inorganic fertilizer usage due to integration of Azolla and Nila fish. An experiment was carried out in Maros, South Sulawesi from December 2005 to March 2006. It was arranged in a split plot design. Results showed that Azolla???Nila integration in rice field increased grain by 17.05% (30.245 kg plot-1) and decreased we...

  1. Phosphorus critical levels and availability in lowland soils cultivated with flooded rice

    OpenAIRE

    Mariano Isabela Orlando dos Santos; Fernandes Luiz Arnaldo; Faquin Valdemar; Andrade Alex Teixeira de

    2002-01-01

    Lowland soils present a great potential for the flooded rice crop. This work aimed to estimate critical levels of P in waterlogged soils cultivated with rice using Mehlich 1 and anion exchange resin as soil-P extractors, compare the performance of these extractors as for the evaluation of the P availability, and study the soil-P fractions involved in the P nutrition of the rice crop. Studied soils consisted of four Histosols: Low Humic Gley (GP), Aluvial (A), Humic Gley (GH) and Bog Soil (O) ...

  2. Remote sensing-based Information for crop monitoring: contribution of SAR and Moderate resolution optical data on Asian rice production

    Science.gov (United States)

    Boschetti, Mirco; Holectz, Francesco; Manfron, Giacinto; Collivignarelli, Francesco; Nelson, Andrew

    2013-04-01

    Updated information on crop typology and status are strongly required to support suitable action to better manage agriculture production and reduce food insecurity. In this field, remote sensing has been demonstrated to be a suitable tool to monitor crop condition however rarely the tested system became really operative. The ones today available, such as the European Commission MARS, are mainly based on the analysis of NDVI time series and required ancillary external information like crop mask to interpret the seasonal signal. This condition is not always guarantied worldwide reducing the potentiality of the remote sensing monitoring. Moreover in tropical countries cloud contamination strongly reduce the possibility of using optical remote sensing data for crop monitoring. In this framework we focused our analysis on the rice production monitoring in Asian tropical area. Rice is in fact the staple food for half of the world population (FAO 2004), in Asia almost 90% of the world's rice is produced and consumed and Rice and poverty often coincide. In this contest the production of reliable rice production information is of extreme interest. We tried to address two important issue in terms of required geospatial information for crop monitoring: rice crop detection (rice map) and seasonal dynamics analysis (phenology). We use both SAR and Optical data in order to exploit the potential complementarity of this system. Multi-temporal ASAR Wide Swath data are in fact the best option to deal with cloud contamination. SAR can easily penetrate the clouds providing information on the surface target. Temporal analysis of archive ASAR data allowed to derived accurate map, at 100m spatial resolution, of permanent rice cultivated areas. On the other and high frequency revisiting optical data, in this case MODIS, have been used to extract seasonal information for the year under analysis. MOD09A1 Surface Reflectance 8-Day L3 Global 500m have been exploited to derive time series of

  3. Dynamics of decadal changes in the distribution of double-cropping rice cultivation in China

    Institute of Scientific and Technical Information of China (English)

    DUAN JuQi; ZHOU GuangSheng

    2013-01-01

    Quantitative description of changes in the distribution of paddy rice cultivation in response to recent climate change provides a reference for rice cultivation patterns and formulation of countermeasures to cope with future climate change in China.This study analyzes the dynamics of decadal changes in distribution of double-cropping rice in China during 1961-2010 in relation to climate change based on the maximum entropy method.Decadal changes in the double-cropping rice cultivation area and climatic suitability in China were apparent.The total area of climatically suitable regions was highest in the 1960s,and subsequently showed an increasing trend at first and then a decreasing trend from the 1970s to 2000s.However,the low climatic suitability area decreased,which implied that the moderate and high climatic suitability areas increased.Among the latter,the high climatic suitability area showed the highest increase in extent to 4.4 times that of the 1990s and four times that of the 1960s.The areas of double-cropping rice cultivation most sensitive to climate change are mainly located in central Jiangsu,central Anhui,the eastern Sichuan Basin,southern Henan and central Guizhou.Transformation of areas between low and moderate climatic suitability was observed in northern Zhejiang,southern Anhui and Hubei,and northern Guangxi.Transformation of areas between moderate and high climatic suitability was observed in central Jiangxi and Leizhou Peninsula.The northern boundary of double-cropping rice cultivation in China shifted southwards and contracted eastwards in the 1970s,and extended northwards in the 1980s.However,the northern boundary did not shift northwards in response to climate warming in the 2000s.

  4. Localization and speciation of mercury in brown rice with implications for pan-Asian public health.

    Science.gov (United States)

    Meng, Bo; Feng, Xinbin; Qiu, Guangle; Anderson, Christopher W N; Wang, Jianxu; Zhao, Lei

    2014-07-15

    Cultivation of paddy rice for human consumption is a dominant agricultural activity throughout Asia. High levels of mercury (Hg) in rice grain pose a potential threat to human health, although the extent of risk is dependent on the chemical speciation of Hg inside the grain. We have investigated the speciation and localization of Hg in three fractions of rice grain (hull, bran, and white rice) collected from a Hg-contaminated region in China. On a mass basis, the majority of inorganic mercury (IHg) in a rice grain is found in hull and bran. However, the majority of the more toxic species methyl mercury (MeHg) is found in edible white rice. Our data show that during grain processing, most of the IHg (∼78%) is eliminated, but the majority of the MeHg remains in the food product (∼80%). Synchrotron radiation microscopic X-ray fluorescence (SR-μXRF) mapping shows strong localization of Hg at the surface of brown rice grains, corresponding to the pericarp and aleurone layer. We infer that this Hg is predominantly IHg absorbed from the atmosphere. Based on X-ray absorption near-edge spectroscopy (XANES) data we propose that IHg in bran is primarily bound to cysteine, and is associated with phytochelatins. Consequently, IHg is largely immobile and restricted to the outer layers of rice grain. MeHg in bran is primarily bound to cysteine and is associated with proteins. However, this MeHg-cysteine association behaves like a mobile nutrient and is actively transported to the endosperm during seed ripening. Concentration of MeHg-cysteine in white rice has implications for public health. There is growing evidence for Hg contamination of rice throughout Asia due to point and diffuse sources of Hg pollution. The magnitude of the associated risk must be quantified through better understanding of the localization and speciation of mercury in rice. Our work makes an effort to contribute to this understanding. PMID:24925231

  5. Independent domestication of Asian rice followed by gene flow from japonica to indica.

    Science.gov (United States)

    Yang, Ching-chia; Kawahara, Yoshihiro; Mizuno, Hiroshi; Wu, Jianzhong; Matsumoto, Takashi; Itoh, Takeshi

    2012-05-01

    Results from studies on the domestication process of Asian rice Oryza sativa have been controversial because of its complicated evolutionary history. Previous studies have yielded two alternative hypotheses about the origin(s) of the two major groups of O. sativa: japonica and indica. One study proposes a single common wild ancestor, whereas the other suggests that there were multiple domestication events of different types of wild rice. Here, we provide clear evidence of the independent domestication of japonica and indica obtained via high-throughput sequencing and a large-scale comparative analysis of two wild rice accessions (W1943 and W0106) and two cultivars (a japonica cultivar called "Nipponbare" and an indica cultivar called "Guangluai-4"). The different domestication processes of the two cultivar groups appear to have led to distinct patterns of molecular evolution in protein-coding regions. The intensity of purifying selection was relaxed only in the japonica group, possibly because of a bottleneck effect. Moreover, a genome-wide comparison between Nipponbare, Guangluai-4, and another indica cultivar (93-11) suggests multiple hybridization events between japonica and indica, both before and after the divergence of the indica cultivars. We found that a large amount of genomic DNA, including domestication-related genes, was transferred from japonica to indica, which might have been important in the development of modern rice. Our study provides an overview of the dynamic process of Asian rice domestication, including independent domestication events and subsequent gene flow.

  6. CULTIVATION OF P. FLORIDA SUPLEMENTED OF RICE BRAIN ON BEECH WOOD WASTE

    Directory of Open Access Journals (Sweden)

    Hüseyin SİVRİKAYA

    1998-03-01

    Full Text Available Cultivation of Pleurotus spp. reached to the second largest in amount after Agaricus bisporus (Lange sing. in the world. There recently has also been growing interest to cultivate them on wastes of forest and agricultural plants in Turkey. In the scope of study Pleurotus florida was produced on beech wood sawmill waste and rice brain. Beech wood sawmill waste (Fagus orientalis Lipsky were used as main substrate and supplemented with rice brain as co-substrate by 10 % W/W, 0 % W/W, 40 % W/W mixing ratios based on dry weights. To produce P. florida substrates were ground, air dried, moistured up to 70-80 % by tap water, supplemented, pasteurized with live steam and spawned. Highest yields (440 gr/kg of P. florida were obtained by supplementing wood waste and rice brain (% 80 + % 20. Furthermore, the best mycelia development were obtained by % 90 + % 10.

  7. Comparison on cellular mechanisms of iron and cadmium accumulation in rice: prospects for cultivating Fe-rich but Cd-free rice.

    Science.gov (United States)

    Gao, Lei; Chang, Jiadong; Chen, Ruijie; Li, Hubo; Lu, Hongfei; Tao, Longxing; Xiong, Jie

    2016-12-01

    Iron (Fe) is essential for rice growth and humans consuming as their staple food but is often deficient because of insoluble Fe(III) in soil for rice growth and limited assimilation for human bodies, while cadmium (Cd) is non-essential and toxic for rice growth and humans if accumulating at high levels. Over-accumulated Cd can cause damage to human bodies. Selecting and breeding Fe-rich but Cd-free rice cultivars are ambitious, challenging and meaningful tasks for researchers. Although evidences show that the mechanisms of Fe/Cd uptake and accumulation in rice are common to some extent as a result of similar entry routes within rice, an increasing number of researchers have discovered distinct mechanisms between Fe/Cd uptake and accumulation in rice. This comprehensive review systematically elaborates and compares cellular mechanisms of Fe/Cd uptake and accumulation in rice, respectively. Mechanisms for maintaining Fe homeostasis and Cd detoxicification are also elucidated. Then, effects of different fertilizer management on Fe/Cd accumulation in rice are discussed. Finally, this review enumerates various approaches for reducing grain Cd accumulation and enhancing Fe content in rice. In summary, understanding of discrepant cellular mechanisms of Fe/Cd accumulation in rice provides guidance for cultivating Fe-fortified rice and has paved the way to develop rice that are tolerant to Cd stress, aiming at breeding Fe-rich but Cd-free rice.

  8. Comparison on cellular mechanisms of iron and cadmium accumulation in rice: prospects for cultivating Fe-rich but Cd-free rice.

    Science.gov (United States)

    Gao, Lei; Chang, Jiadong; Chen, Ruijie; Li, Hubo; Lu, Hongfei; Tao, Longxing; Xiong, Jie

    2016-12-01

    Iron (Fe) is essential for rice growth and humans consuming as their staple food but is often deficient because of insoluble Fe(III) in soil for rice growth and limited assimilation for human bodies, while cadmium (Cd) is non-essential and toxic for rice growth and humans if accumulating at high levels. Over-accumulated Cd can cause damage to human bodies. Selecting and breeding Fe-rich but Cd-free rice cultivars are ambitious, challenging and meaningful tasks for researchers. Although evidences show that the mechanisms of Fe/Cd uptake and accumulation in rice are common to some extent as a result of similar entry routes within rice, an increasing number of researchers have discovered distinct mechanisms between Fe/Cd uptake and accumulation in rice. This comprehensive review systematically elaborates and compares cellular mechanisms of Fe/Cd uptake and accumulation in rice, respectively. Mechanisms for maintaining Fe homeostasis and Cd detoxicification are also elucidated. Then, effects of different fertilizer management on Fe/Cd accumulation in rice are discussed. Finally, this review enumerates various approaches for reducing grain Cd accumulation and enhancing Fe content in rice. In summary, understanding of discrepant cellular mechanisms of Fe/Cd accumulation in rice provides guidance for cultivating Fe-fortified rice and has paved the way to develop rice that are tolerant to Cd stress, aiming at breeding Fe-rich but Cd-free rice. PMID:27502932

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

    International Nuclear Information System (INIS)

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

  10. Cultivation Techniques of Bacteria-Melon-Rice Cultivation Pattern%菌-瓜-稻耕作模式示范栽培技术

    Institute of Scientific and Technical Information of China (English)

    颜舜杨

    2014-01-01

    In recent year, Bacteria-Melon-Rice Cultivation Pattern was promoted in Jianyang county, which achieved good economic benefits. In this paper, we introduced planting performance and high-yielding cultivation techniques of Bacteria-Melon-Rice cultivation pattern.%近年建阳市进行菌—瓜—稻模式试验示范,取得很好的经济效益。介绍了菌—瓜—稻模式示范的栽培技术。

  11. Uptake of Arsenic in Rice Plant Varieties Cultivated with Arsenic Rich Groundwater

    Directory of Open Access Journals (Sweden)

    Piyal Bhattacharya

    2010-07-01

    Full Text Available Groundwater of many areas of West Bengal, India is severely contaminated with arsenic. The paddy soil gets con¬taminated from the groundwater and thus there is a probability of bioaccumulation of arsenic in rice plants cultivated with arsenic contaminated groundwater and soil. This study aims at assessing the level of arsenic in irrigation water and soil and to investigate the seasonal bioaccumulation of arsenic in the various parts (straw, husk and grain of the rice plant of differ¬ent varieties in the arsenic affected two blocks (Chakdaha and Ranaghat-I of Nadia district, West Bengal. It was found that the arsenic uptake in rice during the pre-monsoon season is more than that of the post-monsoon season. The accumulation of arsenic found to vary with different rice varieties; the maximum accumulation was in White minikit (0.31±0.005 mg/kg and IR 50 (0.29±0.001 mg/kg rice varieties and minimum was found to be in the Jaya rice variety (0.14±0.002 mg/kg. In rice plant maximum arsenic accumulation occurred in the straw part (0.89±0.019-1.65±0.021 mg/kg compared to the ac¬cumulation in husk (0.31±0.011-0.85±0.016 mg/kg and grain (0.14±0.002-0.31±0.005 mg/kg parts. For any rice sample concentration of arsenic in the grain did not exceed the WHO recommended permissible limit in rice (1.0 mg/kg.

  12. Decline of traditional rice farming constrains the recovery of the endangered Asian crested ibis (Nipponia nippon).

    Science.gov (United States)

    Sun, Yiwen; Wang, Tiejun; Skidmore, Andrew K; Wang, Qi; Ding, Changqing

    2015-12-01

    Traditional agriculture benefits a rich diversity of plants and animals. The winter-flooded rice fields in the Qinling Mountains, China, are the last refuge for the endangered Asian crested ibis (Nipponia nippon), and intensive efforts have been made to protect this anthropogenic habitat. Analyses of multi-temporal satellite data indicate that winter-flooded rice fields have been continuously reduced across the current range of crested ibis during the past two decades. The rate of loss of these fields in the core-protected areas has unexpectedly increased to a higher level than that in non-protected areas in the past decade. The best fit (R (2) = 0.87) numerical response model of the crested ibis population shows that a reduction of winter-flooded rice fields decreases population growth and predicts that the population growth will be constrained by the decline of traditional winter-flooded rice fields in the coming decades. Our findings suggest that the decline of traditional rice farming is likely to continue to pose a threat to the long-term survival and recovery of the crested ibis population in China.

  13. Multi-mycotoxin screening reveals separate occurrence of aflatoxins and ochratoxin a in Asian rice.

    Science.gov (United States)

    Lim, Chee Wei; Yoshinari, Tomoya; Layne, Jeff; Chan, Sheot Harn

    2015-04-01

    The determination of important regulated mycotoxins in rice has been reported previously but not in the individual matrix of white, brown, red, and basmati rice with respect to the matrix effect, recovery, and stability. A total of 190 Asian rices were examined for regulated mycotoxin contamination by the LC-ESI-MS/MS method. Significant variation (p < 0.05) in the matrix effect was observed for fumonisins. Methanol improved the limits of detection (LOD) for HT-2 from 50 μg/kg to 2.3 μg/kg by promoting ionization efficiency of the ammonium-adduct. LOD and limits of quantitation ranged from 0.1 to 18 μg/kg and 0.2-31 μg/kg, respectively. All analytes degraded by more than 50% on storage, except fumonisins. Acetic acid (1%) provided significant improvement (p < 0.05) in recovery for all analytes in selected white rice from Thailand and China. Mean recovery ranged from 70 to 120%. RSD values were lower than 15% for all analytes. Five AFB1 and single OTA positive samples were detected. No correlation between mycotoxin contamination and rice species (r = 0) exists.

  14. The Physical Location of Gm-2 and Gm-6 in O.officinalis with BAC-FISH Based on Comparative RFLP Map of Wild Rice and Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    QIN Rui; WEI Wen-hui; NING Shun-bin; JIN Wei-wei; HE Guang-cun; SONG Yun-chun

    2002-01-01

    Rice BAC library is used widely in rice genome research due to its distinctive advantages over other library systems. In this study, two rice BAC clones closely linked to rice gall midge resistance, Gm-2 and Gm-6, were in situ hybridized to Oryza officinalis chromosomes. They were located on the long arm of chromosome 4 with FL 72.33% and 77.10% respectively and their FL was consistent with the selective marker of rice, RG214 and RZ569. The frequency of signal detection was 61.2% and 59.5% respectively.Our study was based on comparative RFLP map of wild rice, O. officinalis, and cultivated rice, O. sativa.

  15. Impact of Credit Disbursement, Area under Cultivation, Fertilizer Consumption and Water Availability on Rice Production in Pakistan (1988-2010)

    OpenAIRE

    Hussain, Anwar Hussain

    2012-01-01

    This study estimates the impact of major agriculture inputs (credit disbursement, area under cultivation, fertilizer consumption and water availability) on total rice production in Pakistan using a time series ranging from 1988 to 2010. The study uses a log-linear Cobb-Douglas production function to estimate the impact and importance of these inputs. It finds that area under cultivation and water availability had a positive and statistically significant impact on rice production a...

  16. Cultivation technique of direct seeding rice%水稻直播栽培技术

    Institute of Scientific and Technical Information of China (English)

    谢建泉

    2012-01-01

    总结水稻直播栽培技术,包括选用良种、种子处理、整地与播种、科学水肥管理、防治病虫草害。%This paper summarized the cultivation technique of direct seeding rice,including selecting improved varieties,seed treatment,soil preparation and planting,scientific fertilizer and water management,prevention and control of diseases and insect and pests.

  17. Mapping of a new gene for brown planthopper resistance in cultivated rice introgressed from Oryza eichingeri

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Wild rice species is an important source of useful genes for cultivated rice improvement. Some accessions of Oryza eichingeri (2n = 24, CC) from Africa confer strong resistance to brown planthopper (BPH), whitebacked planthopper (WBPH) and bacterial blight (BB). In the present study, restriction fragments length polymorphism (RFLP) and simple sequence repeats (SSR) analysis were performed on disomic backcross plants between Oryza sativa (2n = 24, AA) and O. eichingeri in order to identify the presenee of O. eichingeri segments and further to localize BPH-resistant gene. In the introgression lines, 1-6O. eichingeri segments were detected on rice chromosomes 1, 2, 6, or/and 10. The dominant BPH resistant gene, tentatively named Bph13(t), was mapped to chromosome 2, being 6.1 and 5.5 cM away from two microsatellite markers RM240 and RM250, respectively. The transfer and localization of this gene from O. eichingeri will contribute to the improvement of BPH resistance in cultivated rice.``

  18. Greenhouse Gas Reductions From Rice Cultivation And The California Cap-and-Trade Market

    Science.gov (United States)

    Parkhurst, R.; Salas, W.; Nichols, L.

    2014-12-01

    The California Air Resources Board is developing a compliance offset protocol for rice cultivation practices. This protocol contains three different activities that growers can take to reduce the generation of methane associated with rice cultivation - dry seeding, early drainage, and alternate wetting and drying of fields. All of these practices have been developed using the latest science and have been shown to reduce methane generation without impacting yield. Methane is the second largest anthropogenic source of greenhouse gas (GHG) emissions, accounting for 9% of all U.S. GHG emissions from human activities. Methane is also important because it is more than 20 times more potent a GHG than carbon dioxide. The rice cultivation protocol is important because it will be the first crop-based protocol considered as a part of California's cap-and-trade program. This session will discuss the latest developments with the protocol from stakeholders involved in the creation of the protocol. We invite you to hear lessons learnt from this experience in order to apply similar approaches to other regions/countries and crops.

  19. An economic evaluation comparison of solar water pumping system with engine pumping system for rice cultivation

    Science.gov (United States)

    Treephak, Kasem; Thongpron, Jutturit; Somsak, Dhirasak; Saelao, Jeerawan; Patcharaprakiti, Nopporn

    2015-08-01

    In this paper we propose the design and economic evaluation of the water pumping systems for rice cultivation using solar energy, gasoline fuel and compare both systems. The design of the water and gasoline engine pumping system were evaluated. The gasoline fuel cost used in rice cultivation in an area of 1.6 acres. Under same conditions of water pumping system is replaced by the photovoltaic system which is composed of a solar panel, a converter and an electric motor pump which is compose of a direct current (DC) motor or an alternating current (AC) motor with an inverter. In addition, the battery is installed to increase the efficiency and productivity of rice cultivation. In order to verify, the simulation and economic evaluation of the storage energy battery system with batteries and without batteries are carried out. Finally the cost of four solar pumping systems was evaluated and compared with that of the gasoline pump. The results showed that the solar pumping system can be used to replace the gasoline water pumping system and DC solar pump has a payback less than 10 years. The systems that can payback the fastest is the DC solar pumping system without batteries storage system. The system the can payback the slowest is AC solar pumping system with batteries storage system. However, VAC motor pump of 220 V can be more easily maintained than the motor pump of 24 VDC and batteries back up system can supply a more stable power to the pump system.

  20. Effects of Non-flooded Cultivation with Straw Mulching on Rice Agronomic Traits and Water Use Efficiency

    Institute of Scientific and Technical Information of China (English)

    QIN Jiang-tao; HU Feng; LI Hui-xin; WANG Yi-ping; HUANG Fa-quan; HUANG Hua-xiang

    2006-01-01

    A field experiment was conducted to study water use efficiency and agronomic traits in rice cultivated in flooded soil and non-flooded soils with and without straw mulching. The total amount of water used by rice under flooded cultivation (FC) was 2.42 and 3.31 times as much as that by rice under the non-flooded cultivation with and without straw mulching, respectively. The average water seepage was 13 560 m3/ha under the flooded cultivation, 4 750 m3/ha under the non-flooded cultivation without straw mulching (ZM)and 4 680 m3/ha under non-flooded cultivation with straw mulching (SM). The evapotranspiration in the SM treatment was only 38.2% and 63.6% of the FC treatment and ZM treatment, respectively. Compared with the ZM treatment, straw mulching significantly increased leaf area per plant, main root length, gross root length and root dry weight per plant of rice. The highest grain yield under the SM treatment (6 747 kg/ha) was close to the rice cultivated in flooded soil (6 811.5 kg / ha). However, the yield under the ZM treatment (4 716 kg/ha) was much lower than that under the FS treatment and SM treatment. The order of water use efficiency and irrigation water use efficiency were both as follows: SM> ZM> FC.

  1. Single-seeded InDel fingerprints in rice: An effective tool for indica-japonica rice classification and evolutionary studies

    Institute of Scientific and Technical Information of China (English)

    Ping LIU; Xing-Xing CAI; Bao-Rong LU

    2012-01-01

    Asian cultivated rice (Oryza sativa L.),an important cereal crop worldwide,was domesticated from its wild ancestor 8000 years ago.During its long-term cultivation and evolution under diverse agroecological conditions,Asian cultivated rice has differentiated into indica and japonica subspecies.An effective method is required to identify rice germplasm for its indica and japonica features,which is essential in rice genetic improvements.We developed a protocol that combined DNA extraction from a single rice seed and the insertion/deletion (InDel)molecular fingerprint to determine the indica and japonica features of rice germplasm.We analyzed a set of rice germplasm,including 166 Asian rice varieties,two African rice varieties,30 accessions of wild rice species,and 42 weedy rice accessions,using the single-seeded InDel fingerprints (SSIF).The results show that the SSIF method can efficiently determine the indica and japonica features of the rice germplasm.Further analyses revealed significant indica and japonica differentiation in most Asian rice varieties and weedy rice accessions.In contrast,African rice varieties and nearly all the wild rice accessions did not exhibit such differentiation.The pattern of cultivated and wild rice samples illustrated by the SSIF supports our previous hypothesis that indica and japonica differentiation occurred after rice domestication under different agroecological conditions.In addition,the divergent pattern of rice cultivars and weedy rice accessions suggests the possibility of an endoferal origin (from crop) of the weedy rice included in the present study.

  2. Heading date 1 (Hd1), an ortholog of Arabidopsis CONSTANS, is a possible target of human selection during domestication to diversify flowering times of cultivated rice.

    Science.gov (United States)

    Takahashi, Yasuyuki; Shimamoto, Ko

    2011-01-01

    During the domestication of rice (Oryza sativa L.), diversification of flowering time was important in expanding the areas of cultivation. Rice is a facultative short day (SD) plant and requires certain periods of dark to induce flowering. Heading date 1 (Hd1), a regulator of the florigen gene Hd3a, is one of the main factors used to generate diversity in flowering. Loss-of-function alleles of Hd1 are common in cultivated rice and cause the diversity of flowering time. However, it is unclear how these functional nucleotide polymorphisms of Hd1 accumulated in the course of evolution. Nucleotide polymorphisms within Hd1 and Hd3a were analyzed in 38 accessions of ancestral wild rice Oryza rufipogon and compared with those of cultivated rice. In contrast to cultivated rice, no nucleotide changes affecting Hd1 function were found in 38 accessions of wild rice ancestors. No functional changes were found in Hd3a in either cultivated or ancestral rice. A phylogenetic analysis indicated that evolution of the Hd1 alleles may have occurred independently in cultivars descended from various accessions of ancestral rice. The non-functional Hd1 alleles found in cultivated rice may be selected during domestication, because they were not found or very rare in wild ancestral rice. In contrast with Hd3a, which has been highly conserved, Hd1 may have undergone human selection to diversify the flowering times of rice during domestication or the early stage of the cultivation period.

  3. Cultivation of rice for animal feed with circulated irrigation of treated municipal wastewater for enhanced nitrogen removal: comparison of cultivation systems feeding irrigation water upward and downward.

    Science.gov (United States)

    Muramatsu, A; Ito, H; Sasaki, A; Kajihara, A; Watanabe, T

    2015-01-01

    To achieve enhanced nitrogen removal, we modified a cultivation system with circulated irrigation of treated municipal wastewater by using rice for animal feed instead of human consumption. The performance of this modified system was evaluated through a bench-scale experiment by comparing the direction of circulated irrigation (i.e. passing through paddy soil upward and downward). The modified system achieved more than three times higher nitrogen removal (3.2 g) than the system in which rice for human consumption was cultivated. The removal efficiency was higher than 99.5%, regardless of the direction of circulated irrigation. Nitrogen in the treated municipal wastewater was adsorbed by the rice plant in this cultivation system as effectively as chemical fertilizer used in normal paddy fields. Circulated irrigation increased the nitrogen released to the atmosphere, probably due to enhanced denitrification. Neither the circulation of irrigation water nor its direction affected the growth of the rice plant and the yield and quality of harvested rice. The yield of rice harvested in this system did not reach the target value in normal paddy fields. To increase this yield, a larger amount of treated wastewater should be applied to the system, considering the significant amount of nitrogen released to the atmosphere.

  4. Effect of Nitrogen Application from Selected Manures on Growth, Nitrogen Uptake and Biomass Production of Cultivated Forage Rice

    Directory of Open Access Journals (Sweden)

    Gusmini Gusmini

    2015-04-01

    Full Text Available Cultivation of forage rice (Oryza sativa L. in paddy field is considered as a promising way to enhanced livestock feed supply. Pot experiment was conducted to evaluate the effects of fermented cattle and poultry manures in different levels of N application on the growth, N uptake and biomass production of forage rice. Rice cv. Tachisuzuka, Kusanohoshi and Hinohikari were grown and treated with five levels of N: 0,7,14,21, and 28 g N m-2.  The results showed that the effects of manures on plant significantly with all levels of N application. The findings indicated that in forage rice cultivation, Tachisuzuka prospects as whole crop silage (WCS because of its highest straw biomass production and suitable feed with WCS quality compared with Kusanohoshi and Hinohikari.  Application of 14 g N m-2 was considered effective for high production of Tachisuzuka forage rice and useful for the reduction of N loading of the environment.

  5. Water Productivity of Irrigated Rice under Transplanting, Wet Seeding and Dry Seeding Methods of Cultivation

    Directory of Open Access Journals (Sweden)

    Murali, NS.

    1997-01-01

    Full Text Available Water productivity (WP of irrigated lowland rice was determined during the 1994 dry (January to May and wet (August to December seasons on a heavy clay acid sulphate soil. Treatments consisted of three cultivation methods : transplanted rice, pregerminated seeds broadcasted on puddled soil (wet seeding and dry seeds broadcasted on unpuddled soil (dry seeding. In wet and dry seeded plots, continuous standing water condition was initiated 17 days after sowing. Total water requirement for rice production was highest in transplanted plots (755 mm in wet season and 1154 mm in dry season and was lowest in dry seeded plots (505 mm in wet season and 1040 mm in dry season. Dry seeding required no water for land preparation but transplanting and wet seeding methods required 18 - 20 % of total water requirement in dry season and 27 - 29 % in wet season. Total percolation was maximum (99 mm in wet season and 215 mm in dry season in dry seeding method and was minimum (62 mm in wet season and 94 mm in dry season in transplanting method. In dry and wet seeding methods, daily percolation gradually decreased with the age of the crop. Total seepage loss did not show any significant difference between the cultivation methods in the two seasons. Grain yield was not affected by the three cultivation methods in both seasons. Water productivity (the ratio between grain yield and total amount of water used in production was 3.5 - 4.1 kg ha-1 mm-1, 3.8 - 4.4 kg ha-1 mm-1 and 4.1 - 5.5 kg ha-1 mm-1 in transplanted, wet seeded and dry seeded rice, respectively. Labour requirement for land preparation and sowing was maximum in transplanted (219 - 226 man-hours ha-1 followed by wet (104 -112 man-hours ha-1 and dry seeded (94 - 99 man-hours ha-1 methods. However, in wet season extra labour (77 man-hours ha-1 was required for weeding after crop establishment in dry and wet seeding methods. Crop maturity was 20 days earlier in wet and dry seeding methods compared to

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

    Directory of Open Access Journals (Sweden)

    Louca Vasilis

    2009-07-01

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

  7. Effect of flaring of natural gas in oil fields of Assam on rice cultivation.

    Science.gov (United States)

    Sharma, K K; Hazarika, S; Kalita, B; Sharma, B

    2011-07-01

    Assam (India) is endowed with natural resources like oil, coal and natural gas. The crude oil, one of the most precious natural resources, is found in the districts of upper Assam. During the process of extraction of crude oil, low-pressure natural gas is burnt in the air. Most of the oil wells in upper Assam are located near rice fields and therefore, rice crop grown near the oil wells is exposed to light uninterruptedly causing grain sterility resulting significant loss in grain yield. To identify promising varieties for these areas, we studied the effect of flare on rice varieties with different photoperiod sensitivity. The high light intensity and increased light hours were the factors responsible for substantial loss in grain yield near the flare resulting from delay in flower initiation, reduction of panicle length, having less number of grains per panicle and more grain sterility. To prevent significant loss in yield, photoperiod-sensitive traditional and improved rice varieties should not be grown up to the distance of 80 and 100 m, respectively from the boundary wall of the flare pit. Modern weakly-photoperiod sensitive varieties like Ranjti and Mahsuri can be grown 40 m away from the wall while modern photoperiod insensitive variety like Jaya, can be cultivated 20 m away from the wall without significant loss in yield. PMID:23029930

  8. Effects of CaMSRB2-Expressing Transgenic Rice Cultivation on Soil Microbial Communities.

    Science.gov (United States)

    Sohn, Soo-In; Oh, Young-Ju; Kim, Byung-Yong; Cho, Hyun-Suk

    2016-07-28

    Although many studies on the effects of genetically modified (GM) crops on soil microorganisms have been carried out over the past decades, they have provided contradictory information, even for the same GM crop, owing to the diversity of the soil environments in which they were conducted. This inconsistency in results suggests that the effects of GM crops on soil microorganisms should be considered from many aspects. In this study, we investigated the effects of the GM drought-tolerant rice MSRB2-Bar-8, which expresses the CaMSRB2 gene, on soil microorganisms based on the culture-dependent and culture-independent methods. To this end, rhizosphere soils of GM and non-GM (IM) rice were analyzed for soil chemistry, population densities of soil microorganisms, and microbial community structure (using pyrosequencing technology) at three growth stages (seedling, tillering, and maturity). There was no significant difference in the soil chemistry between GM and non-GM rice. The microbial densities of the GM soils were found to be within the range of those of the non-GM rice. In the pyrosequencing analyses, Proteobacteria and Chloroflexi were dominant at the seedling stage, while Chloroflexi showed dominance over Proteobacteria at the maturity stage in both the GM and non-GM soils. An UPGMA dendrogram showed that the soil microbial communities were clustered by growth stage. Taken together, the results from this study suggest that the effects of MSRB2-Bar-8 cultivation on soil microorganisms are not significant. PMID:27090184

  9. Managing Water and Soils to Achieve Adaptation and Reduce Methane Emissions and Arsenic Contamination in Asian Rice Production

    OpenAIRE

    Dennis Wichelns

    2016-01-01

    Rice production is susceptible to damage from the changes in temperature and rainfall patterns, and in the frequency of major storm events that will accompany climate change. Deltaic areas, in which millions of farmers cultivate from one to three crops of rice per year, are susceptible also to the impacts of a rising sea level, submergence during major storm events, and saline intrusion into groundwater and surface water resources. In this paper, I review the current state of knowledge regard...

  10. Effect of planting methods and cyanobacterial inoculants on yield, water productivity and economics of rice cultivation

    Directory of Open Access Journals (Sweden)

    Amit A. Shahane

    2015-09-01

    Full Text Available The impact of two crop planting methods and of the application of cyanobacterial inoculants on plant growth, yield, water productivity and economics of rice cultivation was evaluated with the help of a split plot designed experiment during the rainy season of 2011 in New Delhi, India. Conventional transplanting and system of rice intensification (SRI were tested as two different planting methods and seven treatments that considered cyanobacterial inoculants and compost were applied with three repetitions each. Results revealed no significant differences in plant performance and crop yield between both planting methods. However, the application of biofilm based BGA bio-fertiliser + 2/3 N had an overall positive impact on both, plant performance (plant height, number of tillers and crop yield (number and weight of panicles as well as on grain and straw yield. Higher net return and a higher benefit-cost ratio were observed in rice fields under SRI planting method, whereas the application of BGA + PGPR + 2/3 N resulted in highest values. Total water productivity and irrigation water productivity was significantly higher under SRI practices (5.95 and 3.67 kg ha^(-1 mm^(-1 compared to practices of conventional transplanting (3.36 and 2.44, meaning that using SRI method, water saving of about 34 % could be achieved and significantly less water was required to produce one kg of rice. This study could show that a combination of plant growth promoting rhizobacteria (PGPR in conjunction with BGA and 2/3 dose of mineral N fertiliser can support crop growth performance, crop yields and reduces overall production cost, wherefore this practices should be used in the integrated nutrient management of rice fields in India.

  11. To What Extent Do Improved Practices Increase Productivity of Small-Scale Rice Cultivation in A Rain-fed Area? : Evidence from Tanzania

    OpenAIRE

    Yuko Nakano; Yuki Tanaka; Keijiro Otsuka

    2014-01-01

    This paper investigates the impact of training provided by a large-scale private farm on the performance of surrounding small-scale rice farmers in a rain-fed area in Tanzania. We found that the training effectively enhances the adoption of improved rice cultivation practices, paddy yield, and profit of rice cultivation by small-holder farmers. In fact, the trainees achieve paddy yield of 5 tons per hectare on average, which is remarkably high for rain-fed rice cultivation. Our results sugges...

  12. Public Expenditures, Private Incentives, and Farmer Adoption: The Economics of Hybrid Rice in South Asia

    OpenAIRE

    Spielman, David J.; Kolady, Deepthi; Cavalieri, Anthony

    2012-01-01

    The rapid expansion of hybrid rice cultivation in China has contributed significantly to improving food security in the country since the 1980s. However, few other Asian countries have seen similar expansions in hybrid rice cultivation or the associated yield and output gains. This paper examines the technical challenges, market opportunities, and policy constraints related to hybrid rice in Asia, with specific emphasis on India and Bangladesh. The paper sets the discussion within a novel ana...

  13. The Early Rice Project: From Domestication to Global Warming

    Directory of Open Access Journals (Sweden)

    Dorian Q. Fuller

    2011-10-01

    Full Text Available The Early Rice Project, at the UCL Institute of Archaeology, is clarifying the origins of Asian rice agriculture. In the Lower Yangtze region of China, we have found the tipping point when domesticated forms first outnumber wild types c.4600 BC. Investigations of assorted weed flora are also revealing how the cultivation of rice changed over time, with early cultivation in small, irregular, dug-out paddy fields in the Lower Yangtze from c.4000 BC, providing a means for the careful control of water conditions. We also work on early rice cultivation in Thailand and India. By better characterising how rice was cultivated across its entire range, we aim to model the ancient output of atmospheric methane from wet rice fields, as this was a potential contributor to the long story of human-caused global warming.

  14. Trends and Variability of Rice, Maize, and Wheat Yields in South Asian Countries: A Challenge for Food Security

    Directory of Open Access Journals (Sweden)

    Mahadeb Prasad Poudel

    2012-12-01

    Full Text Available During the last six decades, the yield and production of rice, maize, and wheat grew remarkably in South Asian region. As these cereals are staple foods, the growth and fluctuation of yields greatly impacts on food security. This study aims to examine the growth patterns and variability of rice, wheat, and maize yields in South Asian countries namely Bangladesh, India, Nepal, Pakistan, and Sri Lanka. Utilizing the yield data during 1961-2010, we applied the linear and quadratic regressions for yield trends and variability analyses. Quadratic model was fitted well in all data sets except wheat yield in Pakistan. A clear indication of slowing growth rates was observed for wheat yield in Bangladesh and India, as well as a significant increase in maize yield variability was realized in Bangladesh, India, Pakistan, and Sri Lank. The factors influencing for slowing yield growth rates are considered as comparative disadvantage of wheat to Boro rice in case of Bangladesh, whereas depletion of soil nutrient contents in the rice-wheat production areas and negative impact of climate change in India. The slowing yield growths exerted a challenge for food security in Bangladesh and India. Thus, policy implementations are urgent to improve the wheat yield growth and maize yield stabilization in the concerning countries.

  15. Managing Water and Soils to Achieve Adaptation and Reduce Methane Emissions and Arsenic Contamination in Asian Rice Production

    Directory of Open Access Journals (Sweden)

    Dennis Wichelns

    2016-04-01

    Full Text Available Rice production is susceptible to damage from the changes in temperature and rainfall patterns, and in the frequency of major storm events that will accompany climate change. Deltaic areas, in which millions of farmers cultivate from one to three crops of rice per year, are susceptible also to the impacts of a rising sea level, submergence during major storm events, and saline intrusion into groundwater and surface water resources. In this paper, I review the current state of knowledge regarding the potential impacts of climate change on rice production and I describe adaptation measures that involve soil and water management. In many areas, farmers will need to modify crop choices, crop calendars, and soil and water management practices as they adapt to climate change. Adaptation measures at the local, regional, and international levels also will be helpful in moderating the potential impacts of climate change on aggregate rice production and on household food security in many countries. Some of the changes in soil and water management and other production practices that will be implemented in response to climate change also will reduce methane generation and release from rice fields. Some of the measures also will reduce the uptake of arsenic in rice plants, thus addressing an important public health issue in portions of South and Southeast Asia. Where feasible, replacing continuously flooded rice production with some form of aerobic rice production, will contribute to achieving adaptation objectives, while also reducing global warming potential and minimizing the risk of negative health impacts due to consumption of arsenic contaminated rice.

  16. Allele distributions at hybrid incompatibility loci facilitate the potential for gene flow between cultivated and weedy rice in the US.

    Directory of Open Access Journals (Sweden)

    Stephanie M Craig

    Full Text Available The accumulation of independent mutations over time in two populations often leads to reproductive isolation. Reproductive isolation between diverging populations may be reinforced by barriers that occur either pre- or postzygotically. Hybrid sterility is the most common form of postzygotic isolation in plants. Four postzygotic sterility loci, comprising three hybrid sterility systems (Sa, s5, DPL, have been recently identified in Oryza sativa. These loci explain, in part, the limited hybridization that occurs between the domesticated cultivated rice varieties, O. sativa spp. japonica and O. sativa spp. indica. In the United States, cultivated fields of japonica rice are often invaded by conspecific weeds that have been shown to be of indica origin. Crop-weed hybrids have been identified in crop fields, but at low frequencies. Here we examined the possible role of these hybrid incompatibility loci in the interaction between cultivated and weedy rice. We identified a novel allele at Sa that seemingly prevents loss of fertility in hybrids. Additionally, we found wide-compatibility type alleles at strikingly high frequencies at the Sa and s5 loci in weed groups, and a general lack of incompatible alleles between crops and weeds at the DPL loci. Our results suggest that weedy individuals, particularly those of the SH and BRH groups, should be able to freely hybridize with the local japonica crop, and that prezygotic factors, such as differences in flowering time, have been more important in limiting weed-crop gene flow in the past. As the selective landscape for weedy rice changes due to increased use of herbicide resistant strains of cultivated rice, the genetic barriers that hinder indica-japonica hybridization cannot be counted on to limit the flow of favorable crop genes into weeds.

  17. Comparison of the abundance and community structure of ammonia oxidizing prokaryotes in rice rhizosphere under three different irrigation cultivation modes.

    Science.gov (United States)

    Zhang, Jinping; Zhou, Xiaohong; Chen, Lei; Chen, Zhigang; Chu, Jinyu; Li, Yimin

    2016-05-01

    The abundance, diversity and community structure of ammonia oxidizing archaea (AOA) and bacteria (AOB) in rice rhizosphere soils under three different irrigation cultivated modes, named continuous irrigation mode (C), intermittent irrigation mode (I) and semi-arid mode (M), respectively, were investigated using amoA gene as a molecular biomarker. Clone libraries and quantitative polymerase chain reaction results indicated the highest number of archaeal amoA gene copy was detected in M cultivation mode, then in I and C, whereas, their order of amoA gene copy numbers were I > M > C for AOB, and those were obvious higher than in the bulk soil. The ratios of AOA/AOB were greater than 1 for all samples, suggested the predominance of AOA throughout the period of rice growth in the three different irrigation cultivation modes. Diversity index (SChao1 and Shannon H) have an obvious variation in three different irrigation cultivation modes. For AOA, SChao1 was highest in M and lowest in I mode, whereas, Shannon H was highest in M cultivation mode and lowest in C mode. For AOB, mode M exhibited the highest diversity index (SChao1 and Shannon H), while C showed the lowest highest diversity, suggested long-term water input (continuous mode) may decrease diversity of ammonia oxidizers, whereas mode M may be more appropriate for them. In addition, AOA sequences fall within Nitrososphaera, Nitrosopumilus and Nitrosotalea cluster with proportion of 89.38, 8.85 and 1.77 %, respectively. AOB gene sequences belonged to the Nitrosomonas and Nitrosospira genera with proportion of 90.97 and 9.03 %, respectively. In addition, the abundances, diversity and community structure had an obvious temporal variation in three developmental stages of rice, further suggested rice growth obviously affected the ammonia oxidizing prokaryotes in their rhizosphere soil. PMID:27038955

  18. 栽培措施对杂草稻和栽培稻生长的影响%Influence of Different Cultivation Measures on the Growth of Weedy Rice and Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    曹旦; 戴伟民; 强胜; 宋小玲

    2011-01-01

    The results show that the growth of weedy rice is inhibited seriously but cultivated rice grows vigorously under transplanting measure and any density of weedy rice. The cultivated rice yield is guaranteed ( up to 3 496. 65 kg/hm2) and weedy rice is inhibited well by transplanting. Under dry direct seeding,because the weedy rice germinates well, the density of weedy rice is high and the yield of cultivated rice decreases by 1 011. 15 kg/hm2 compared with transplanting. The inhibited influence of water direct seeding on the emergence rate of weedy rice is more serious than that of dry direct seeding. Under water direct seeding, the emergence rate of weedy rice is 9.14% lower than that of dry direct seeding,however, the growth of weedy rice is not inhibited after emergence. Therefore weedy rice occurred at a large amount of 1 219.35 kg/hm2,the cultivated rice yield is only 1 829. 85 kg/hm2. With the increasing of weedy rice density, the effect on their own population show that the dry biomass of above ground parts decreases significantly and 50% heading time of weedy rice is postponed;the impact on cultivated rice is that cultivated rice decreases in many aspects, such as the widths of flag leaves, tiller numbers, effective spike numbers, the dry biomass of above ground parts, panicle lengths, the full filled grain numbers, 1 000 - grains weight and actual yield etc. According to the above all results, transplanting measure should be applied in the farming field of weedy rice occurring seriously; water direct seeding should be applied in field of occurring medium seriously,and the sowing norm of cultivated rice should increase appropriately;dry direct seeding should be applied in low one in order to balance the payment and interests.%无论何种杂草稻密度和移栽措施下,杂草稻生长受到明显抑制,栽培稻生长没有受到明显影响,移栽不仅较好地抑制了杂草稻的发生,同时保证水稻产量,使产量达到3 496.65 kg/hm2.旱直播

  19. Identification of β-phenylalanine as a non-protein amino acid in cultivated rice, Oryza sativa.

    Science.gov (United States)

    Yokoo, Takayuki; Takata, Ryo; Yan, Jian; Matsumoto, Fuka; Teraishi, Masayoshi; Okumoto, Yutaka; Jander, Georg; Mori, Naoki

    2015-01-01

    Non-protein amino acids, often analogs of the standard 20 protein amino acids, have been discovered in many plant species. Recent research with cultivated rice (Oryza sativa) identified (3R)-β-tyrosine, as well as a tyrosine amino mutase that synthesizes (3R)-β-tyrosine from the protein amino acid (2S)-α-tyrosine. Gas chromatography-mass spectrometry (GC-MS) assays and comparison to an authentic standard showed that β-phenylalanine is also a relatively abundant non-protein amino acid in rice leaves and that its biosynthesis occurs independently from that of β-tyrosine.

  20. Study on Difference in Cold Tolerance Between Weedy Rice and Cultivated Rice in Heilongjiang Province of China

    Institute of Scientific and Technical Information of China (English)

    ZOU Detang; GUO Junxiang; LIU Hualong; WANG Jingguo

    2008-01-01

    A long-red awn weedy rice and rice cultivars named Ken99004(ZC1),Crossing-503(ZC2),Ken Sticky Riee(ZC3),Shashani(ZC4),Long-Grain Aromatic Rice(ZC5) were used to study typical wild traits of weedy rice and to identify the cold resistance of all genotypes.The results showed that the stem of long-red awn weedy rice was the weakest. No difference was found in the early stage of rice growth,e.g.the vegetable growth stage,between long-red awn weedy rice and other rice cultivars in the stem rigidity,but in the later stage,or reproductive growth stage,their leaves and stems were senescent rapidly because of the speedy supply of nutrients for panicle growth,meanwhile the rigidity of stem was reduced sharply just as withered weeds.The germination rate of longred awn weedy flee was the highest in cold condition,and in turn were ZC1,ZC2,ZC3,ZC4,ZC5,respectively.The performances of genotypes in cold tolerance were identical,those with a high ability of germination in low temperature also showed a strong cold tolerance in main traits in whole growth period,the order from strong to weak in the extent of cold tolerance were long-red awn weedy rice,ZC1,ZC2,ZC3,ZC4,ZC5,respectively.

  1. Analysis of rhizosphere bacteria of rice cultivated in Andosol lowland and upland fields using molecular biological methods

    OpenAIRE

    DOI, Tetsuya; Hagiwara, Yusuke; Abe, Jun; Morita, Shigenori

    2007-01-01

    Bacteria in the rhizosphere influence plant growth and interact with plant roots. Microscopy and culture method have been used for studies of microorganisms of the rhizosphere, but these methods are insufficient for evaluation because most rhizosphere bacteria are viable but non-culturable (VBNC). Bacteria in the rhizosphere of rice cultivated in Andosol lowland and upland fields were analyzed in this study using PCR-DGGE and FISH, in combination with modified pretreatments. Results show that...

  2. Organoleptic qualities and acceptability of fortified rice in two Southeast Asian countries

    DEFF Research Database (Denmark)

    Khanh Van, Tran; Burja, Kurt; Thuy Nga, Tran;

    2014-01-01

    Fortified rice has the potential to improve the micronutrients status of vulnerable populations. However, fortified rice has to have acceptable organoleptic--the sensory properties of a particular food--qualities. Few data exist on the acceptability of fortified rice in Asia. To assess the accept......Fortified rice has the potential to improve the micronutrients status of vulnerable populations. However, fortified rice has to have acceptable organoleptic--the sensory properties of a particular food--qualities. Few data exist on the acceptability of fortified rice in Asia. To assess...... the acceptability of two types of fortified rice (cold and hot extruded) in Vietnam and Cambodia, triangle tests were conducted in Vietnam (53 women) and Cambodia (258 adults), testing fortified rice against conventional rice, with participants being asked to score the organoleptic qualities. In addition, Cambodian...... schoolchildren (n = 1700) were given conventional rice and two types of fortified rice for two week periods as part of a World Food Program school meal program, with intake monitored. Fortified rice differed significantly in organoleptic qualities from conventional rice, with most subjects correctly identifying...

  3. Plant available silicon in South-east Asian rice paddy soils - relevance of agricultural practice and of abiotic factors

    Science.gov (United States)

    Marxen, A.; Klotzbücher, T.; Vetterlein, D.; Jahn, R.

    2012-12-01

    Background Silicon (Si) plays a crucial role in rice production. Si content of rice plants exceeds the content of other major nutrients such as nitrogen, phosphorous or potassium. Recent studies showed that in some environments external supply of Si can enhance the growth of rice plants. Rice plants express specific Si transporters to absorb Si from soil solutions in form of silicic acid, which precipitates in tissue cells forming amorphous silica bodies, called phytoliths. The phytoliths are returned to soils with plant residues. They might be a main source of plant available silicic acid in soils. Aims In this study we assess the effects of rice paddy cultivation on the stocks of `reactive` Si fractions in mineral topsoils of rice paddy fields in contrasting landscapes. The `reactive` Si fractions are presumed to determine the release of plant-available silicic acid in soils. We consider the relevance of abiotic factors (mineral assemblage; soil weathering status) and agricultural practice for these fractions. Agricultural practices, which were assumed to affect the stocks of `reactive` Si were (i) the usage of different rice varieties (which might differ in Si demand), (ii) straw residue management (i.e., whether straw residues are returned to the fields or removed and used e.g. as fodder), and (iii) yield level and number of crops per year. Material and methods Soils (top horizon of about 0-20 cm depth) were sampled from rice paddy fields in 2 mountainous and 5 lowland landscapes of contrasting geologic conditions in Vietnam and the Philippines. Ten paddy fields were sampled per landscape. The rice paddy management within landscapes differed when different farmers and/or communities managed the fields. We analysed the following fractions of `reactive` Si in the soils: acetate-extractable Si (dissolved and easily exchangeable Si), phosphate-extractable Si (adsorbed Si), oxalate extractable Si (Si associated with poorly-ordered sesquioxides), NaOH extractable Si

  4. Study on the Practice and High-yielding Mechanism of Super-sparse-cultivation Associated with Maximum-tiller Seedling of Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    MA Jun; TAO Shi-shun

    2002-01-01

    In this paper, a new cultivation practice-super-sparse-cultivation associated with maximumtiller seedling (SSCMTS) of hybrid rice was proposed and its high-yielding mechanism was studied. The results showed that the practice of SSCMTS in hybrid rice could not only increase grain yield but also save seeds and labor. It was a new high-yielding way for the late transplanting seedlings and heavy panicle type hybrid rice cultivars to further utilize the high-yielding potential of hybrid rice cultivars. The increasing number of spikelets and ideal grain -filling were the direct factors for the high yield of SSCMTS in hybrid rice, and those high-yielding factors relied on high quality seedlings, sturdy individuals, high quality population and vigorous later growth.

  5. Azolla-Anabaena as a Biofertilizer for Rice Paddy Fields in the Po Valley, a Temperate Rice Area in Northern Italy

    OpenAIRE

    Stefano Bocchi; Antonino Malgioglio

    2010-01-01

    Azolla is a floating pteridophyte, which contains as endosymbiont the nitrogen-fixing cyanobacterium Anabaena azollae (Nostocaceae family). Widely cultivated in the Asian regions, Azolla is either incorporated into the soil before rice transplanting or grown as a dual crop along with rice. To examine the feasibility of its use in flooded rice fields sited in the Temperate European Areas, we carried out a series of experiments in PVC tanks during 2000–2002 in Po Valley (northern Italy) conditi...

  6. Evolutionary Genomics of Weedy Rice in the USA

    Institute of Scientific and Technical Information of China (English)

    Kenneth M. Olsen; Ana L. Caicedo; Yulin Jia

    2007-01-01

    Red rice is an interfertile, weedy form of cultivated rice (Oryza sativa L.) that competes aggressively with the crop in the southern US, reducing yields and contaminating harvests. No wild Oryza species occur in North America and the weed has been proposed to have evolved through multiple mechanisms, including "de-domestication" of US crop cultivars, accidental introduction of Asian weeds, and hybridization between US crops and Asian wild/weedy Oryza strains. The phenotype of US red rice ranges from "crop mimics", which share some domestication traits with the crop, to strains closely resembling Asian wild Oryza species. Assessments of genetic diversity have indicated that many weed strains are closely related to Asian taxa (including indica and aus rice varieties, which have never been cultivated in the US, and the Asian crop progenitor O. rufipogon), whereas others show genetic similarity to the tropical japonlca varieties cultivated in the southern US. Herein, we review what is known about the evolutionary origins and genetic diversity of US red rice and describe an ongoing research project to further characterize the evolutionary genomics of this aggressive weed.

  7. A Genetic Model for the Female Sterility Barrier Between Asian and African Cultivated Rice Species

    Science.gov (United States)

    Garavito, Andrea; Guyot, Romain; Lozano, Jaime; Gavory, Frédérick; Samain, Sylvie; Panaud, Olivier; Tohme, Joe; Ghesquière, Alain; Lorieux, Mathias

    2010-01-01

    S1 is the most important locus acting as a reproductive barrier between Oryza sativa and O. glaberrima. It is a complex locus, with factors that may affect male and female fertility separately. Recently, the component causing the allelic elimination of pollen was fine mapped. However, the position and nature of the component causing female sterility remains unknown. To fine map the factor of the S1 locus affecting female fertility, we developed a mapping approach based on the evaluation of the degree of female transmission ratio distortion (fTRD) of markers. Through implementing this methodology in four O. sativa × O. glaberrima crosses, the female component of the S1 locus was mapped into a 27.8-kb (O. sativa) and 50.3-kb (O. glaberrima) region included within the interval bearing the male component of the locus. Moreover, evidence of additional factors interacting with S1 was also found. In light of the available data, a model where incompatibilities in epistatic interactions between S1 and the additional factors are the cause of the female sterility barrier between O. sativa and O. glaberrima was developed to explain the female sterility and the TRD mediated by S1. According to our model, the recombination ratio and allelic combinations between these factors would determine the final allelic frequencies observed for a given cross. PMID:20457876

  8. Effects of cultivation of Osr HSA transgenic rice on functional diversity of microbial communities in the soil rhizosphere

    Institute of Scientific and Technical Information of China (English)

    Xiaobing; Zhang; Xujing; Wang; Qiaoling; Tang; Ning; Li; Peilei; Liu; Yufeng; Dong; Weimin; Pang; Jiangtao; Yang; Zhixing; Wang

    2015-01-01

    With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate the possible effects of Osr HSA transgenic rice on soil microbial utilization of carbon substrates under field conditions. There were no significant differences in average well-color development(AWCD) values, Shannon–Wiener diversity index(H), Simpson dominance indices(D) and Shannon–Wiener evenness indices(E) of microbial communities in rhizosphere soils at eight samplings between Osr HSA transgenic rice and its non-transgenic counterpart. The main carbon sources utilized by soil microbes were carbohydrates, carboxylic acids, amino acids and polymers. The types,capacities and patterns of carbon source utilization by microbial communities in rhizosphere soils were similar throughout the detection period. We detected no Osr HSA protein in the roots of Osr HSA transgenic rice. We concluded that Osr HSA transgenic rice and the r HSA protein it produced did not alter the functional diversity of microbial communities in the rhizosphere.

  9. REVIEW ON BANDED LEAF AND SHEATH BLIGHT OF RICE CAUSED BY Rhizoctonia solani KUHN

    OpenAIRE

    P. Srinivas; Ved Ratan; Atm Prakash Patel; G. Bindu Madhavi

    2013-01-01

    Rice (Oryza sativa L.) is a graminaceous crop. It is one of the important staple foods for Asian countries. Sheath blight disease is an important fungal disease of rice. Currently, this disease is distributed in almost all the rice growing states. The disease is alarming due to its intensive cultivation of modern high yielding varieties with high doses of nitrogenous fertilizers. Crop with a high plant density and close canopy associated favors disease build up from panicle initiation onwards...

  10. Analysis of Stress-Responsive Gene Expression in Cultivated and Weedy Rice Differing in Cold Stress Tolerance.

    Science.gov (United States)

    Bevilacqua, Caroline Borges; Basu, Supratim; Pereira, Andy; Tseng, Te-Ming; Zimmer, Paulo Dejalma; Burgos, Nilda Roma

    2015-01-01

    Rice (Oryza sativa L.) cultivars show impairment of growth in response to environmental stresses such as cold at the early seedling stage. Locally adapted weedy rice is able to survive under adverse environmental conditions, and can emerge in fields from greater soil depth. Cold-tolerant weedy rice can be a good genetic source for developing cold-tolerant, weed-competitive rice cultivars. An in-depth analysis is presented here of diverse indica and japonica rice genotypes, mostly weedy rice, for cold stress response to provide an understanding of different stress adaptive mechanisms towards improvement of the rice crop performance in the field. We have tested a collection of weedy rice genotypes to: 1) classify the subspecies (ssp.) grouping (japonica or indica) of 21 accessions; 2) evaluate their sensitivity to cold stress; and 3) analyze the expression of stress-responsive genes under cold stress and a combination of cold and depth stress. Seeds were germinated at 25°C at 1.5- and 10-cm sowing depth for 10d. Seedlings were then exposed to cold stress at 10°C for 6, 24 and 96h, and the expression of cold-, anoxia-, and submergence-inducible genes was analyzed. Control plants were seeded at 1.5cm depth and kept at 25°C. The analysis revealed that cold stress signaling in indica genotypes is more complex than that of japonica as it operates via both the CBF-dependent and CBF-independent pathways, implicated through induction of transcription factors including OsNAC2, OsMYB46 and OsF-BOX28. When plants were exposed to cold + sowing depth stress, a complex signaling network was induced that involved cross talk between stresses mediated by CBF-dependent and CBF-independent pathways to circumvent the detrimental effects of stresses. The experiments revealed the importance of the CBF regulon for tolerance to both stresses in japonica and indica ssp. The mechanisms for cold tolerance differed among weedy indica genotypes and also between weedy indica and cultivated

  11. Analysis of Stress-Responsive Gene Expression in Cultivated and Weedy Rice Differing in Cold Stress Tolerance.

    Directory of Open Access Journals (Sweden)

    Caroline Borges Bevilacqua

    Full Text Available Rice (Oryza sativa L. cultivars show impairment of growth in response to environmental stresses such as cold at the early seedling stage. Locally adapted weedy rice is able to survive under adverse environmental conditions, and can emerge in fields from greater soil depth. Cold-tolerant weedy rice can be a good genetic source for developing cold-tolerant, weed-competitive rice cultivars. An in-depth analysis is presented here of diverse indica and japonica rice genotypes, mostly weedy rice, for cold stress response to provide an understanding of different stress adaptive mechanisms towards improvement of the rice crop performance in the field. We have tested a collection of weedy rice genotypes to: 1 classify the subspecies (ssp. grouping (japonica or indica of 21 accessions; 2 evaluate their sensitivity to cold stress; and 3 analyze the expression of stress-responsive genes under cold stress and a combination of cold and depth stress. Seeds were germinated at 25°C at 1.5- and 10-cm sowing depth for 10d. Seedlings were then exposed to cold stress at 10°C for 6, 24 and 96h, and the expression of cold-, anoxia-, and submergence-inducible genes was analyzed. Control plants were seeded at 1.5cm depth and kept at 25°C. The analysis revealed that cold stress signaling in indica genotypes is more complex than that of japonica as it operates via both the CBF-dependent and CBF-independent pathways, implicated through induction of transcription factors including OsNAC2, OsMYB46 and OsF-BOX28. When plants were exposed to cold + sowing depth stress, a complex signaling network was induced that involved cross talk between stresses mediated by CBF-dependent and CBF-independent pathways to circumvent the detrimental effects of stresses. The experiments revealed the importance of the CBF regulon for tolerance to both stresses in japonica and indica ssp. The mechanisms for cold tolerance differed among weedy indica genotypes and also between weedy indica and

  12. Ionome of rice seed response to rice cultivation patterns%水稻种植模式对水稻籽粒离子组的影响

    Institute of Scientific and Technical Information of China (English)

    沙之敏; 袁婧; 赵峥; 岳玉波; 姚健; 曹林奎

    2016-01-01

    subcellular compartment, cell, tissue or organism is termed as ionome, which involves of all mineral elements of life, regardless of chemical forms these occur. Ionome is the inorganic chemical element fingerprint of plant that quantitatively and accurately reflects inorganic response of plants to environment stimuli. A field experiment was conducted to explore the differences and correlations of mineral elements in rice seeds cultivated in conventional cultivation ecosystem, green rice-frog ecosystem and organic rice-frog ecosystem under long-term management. The study also determined the transportability of available elements from soil to rice seeds to explore the correlation of elements between soil and rice seed. The concentrations of 21 mineral elements in the rice samples and soil were determined using high-throughput elemental analysis technology such as inductively coupled plasma optical emission and mass spectrometry (ICP-MS). Statistical method used to profile multi-elemental composition, and principle component analysis (PCA) to discriminate differences among treatments. Then ANOVA analysis was used to compare the differences among treatments for each element. The results showed the ranked order of the concentrations of 21 elements in rice seeds was:potassium (K)>phosphorus (P)>magnesium (Mg)>calcium (Ca)>manganese (Mn)>zinc (Zn)>ion (Fe)>copper (Cu)>rubidium (Rb)>sodium (Na)>barium (Ba)>molybdenum (Mo)>boron (B)>nickel (Ni)>strontium (Sr)>arsenic (As)>chromium (Cr)>cadmium (Cd)>selenium (Se)>cobalt (Co)>cesium (Cs). PCA analysis showed that ionome of rice seeds was significantly affected by different cultivation patterns. The fist component accounted for 32.7% of the total variation, which separated organic rice-frog ecosystem from organic rice-frog ecosystem. The second component accounted for 27.1%of the total variation, which discriminated conventional cultivation system from the other two ecosystems. Compared with conventional cultivation, the concentrations

  13. Upscaling regional emissions of greenhouse gases from rice cultivation: methods and sources of uncertainty

    NARCIS (Netherlands)

    Verburg, P.H.; Bodegom, van P.M.; Denier van der Gon, H.A.C.; Bergsma, A.; Breemen, van N.

    2006-01-01

    One of the important sources of greenhouse gases is the emission of methane from rice fields. Methane emission from rice fields is the result of a complex array of soil processes involving plant-microbe interactions. The cumulative effects of these processes at the level of individual plants influen

  14. Suitability assessment and mapping of Oyo State, Nigeria, for rice cultivation using GIS

    Science.gov (United States)

    Ayoade, Modupe Alake

    2016-07-01

    Rice is one of the most preferred food crops in Nigeria. However, local rice production has declined with the oil boom of the 1970s causing demand to outstrip supply. Rice production can be increased through the integration of Geographic Information Systems (GIS) and crop-land suitability analysis and mapping. Based on the key predictor variables that determine rice yield mentioned in relevant literature, data on rainfall, temperature, relative humidity, slope, and soil of Oyo state were obtained. To develop rice suitability maps for the state, two MCE-GIS techniques, namely the Overlay approach and weighted linear combination (WLC), using fuzzy AHP were used and compared. A Boolean land use map derived from a landsat imagery was used in masking out areas currently unavailable for rice production. Both suitability maps were classified into four categories of very suitable, suitable, moderate, and fairly moderate. Although the maps differ slightly, the overlay and WLC (AHP) approach found most parts of Oyo state (51.79 and 82.9 % respectively) to be moderately suitable for rice production. However, in areas like Eruwa, Oyo, and Shaki, rainfall amount received needs to be supplemented by irrigation for increased rice yield.

  15. Voices from the marsh: Livelihood concerns of fishers and rice cultivators in the Alaotra wetland

    Directory of Open Access Journals (Sweden)

    Lala Jean Rakotoniaina

    2009-06-01

    Full Text Available Lake Alaotra is the largest lake on Madagascar and is a centre of rice and freshwater fish production. The lake and its wetland also provide important habitat for endemic wildlife. In 2003 the Alaotra wetland system was designated a Ramsar site and has subsequently been recognized as an official protected area by the Government of Madagascar. While community - based conservation initiatives have led to active involvement of some lakeside communities in the conservation of the aquatic system, wetland destruction continues. The extent to which individuals within these communities perceive the protection of the environment as their priority remains unclear. The current study collected socio - economic data from fishers and rice cultivators living in Anororo, a small town situated on the west coast of Lake Alaotra. Results suggest that livelihood security within these groups is limited. While they hope for better protection of the environment their primary concern is for external investment in their professions. These results highlight the need for solutions to be found to meet current livelihood priorities while efforts continue to conserve natural resources for the future. RÉSUMÉ: Le lac Alaotra est le plus grand lac de Madagascar et il est un centre de production rizicole et piscicole. Le lac qui a une superficie de 20,000 ha et les zones humides qui l’entourent constituent aussi un habitat important pour des espèces fauniques endémiques. Les initiatives de conservation communautaire impliquant des communautés riveraines dans les actions de protection du système aquatique n’empêchent pas la destruction des zones humides. L’extension des rizières dans les marais de la Nouvelle Aire Protégée (NAP que des gens de ces communautés pratiquent, montre que ceux - ci perçoivent mal l’importance de la protection de l’environnement, et qu’ils sont loin de pouvoir la considérer en tant que priorité. L’étude actuelle est bas

  16. RICE (Oryza sativa L. CULTIVATION AND IT’S GEOGRAPHICAL DISTRIBUTIONIN TURKEY

    Directory of Open Access Journals (Sweden)

    Nuran TAŞLIGİL

    2011-06-01

    Full Text Available Rice is one of the staple foods in the world. Rice in the husk is a cereal whose breeding depends on a special access because of the climate it needs can create a malaria epidemic. Turkey is one of the major countries in rice in the husk breeding. In Turkey, the accretion in the amount of the rice for each person especially after 1980, caused an accretion in the export of the notch. As a matter of fact, the production and the breeding of the notch changes every year acording to the economy, ecology and the marketing channels. However, according to the last istatistics it has been understood that the rice plantation areas in Marmara Region and Edirne showed distinction among the whole country.

  17. Effect of Gamma Rays on Seed Germination, Seedling Height, Survival Percentage and Tiller Production in Some Rice Varieties Cultivated in Sierra Leone

    OpenAIRE

    Harding, S. S.; Johnson, S D.; Taylor, D R; Dixon, C.A.; Turay, M. Y.

    2012-01-01

    Thirteen rice varieties cultivated in Sierra Leone were used to examine varietal differences in radiosensitivity to gamma radiation during the wet season of 2006 in the lowland ecology. Dry seeds of rice varieties were exposed to gamma radiation ranging from 50 to 800 Gy to determine their responses to radiation and the effective radiation dose for mutation breeding. Percentage germination, percentage survival (field condition), seedling height and tiller production were the traits measured o...

  18. Natural herbicide resistance (HR) to broad-spectrum herbicide, glyphosate among traditional and inbred-cultivated rice (Oryza sativa L.) varieties in Sri Lanka.

    Science.gov (United States)

    Weerakoon, S R; Somaratne, S; Wijeratne, R G D; Ekanyaka, E M S I

    2013-08-15

    Weeds along with insect pests and plant diseases are sources of biotic stress in crop systems. Weeds are responsible for serious problems in rice worldwide affecting growth and causing a considerable reduction in quality and quantity in yield. High concentrations of pre-emergent-broad-spectrum systemic herbicide, Glyphosate is prevalently applied to control rice weeds which intern causes severe damages to cultivated rice varieties, susceptible to Glyphosate. However, there may be rice varieties with natural Herbicide Resistance (HR) which are so far, has not been evaluated. In this study Six traditional and eighteen developed-cultivated rice varieties (Bg, Bw, At and Ld series developed by Rice Research Development Institute, Sri Lanka) were used to screen their natural HR. RCBD with five replicates and three blocks in each treatment-combination was used as the experimental design. As observations, time taken-to seed germination, time taken to flowering; plant height and number of leaves at 12-weeks after sawing, leaf-length, breadth, panicle-length, number of seeds/panicle of resistant plants and controls were recorded. Plants with > or = 40% resistance were considered as resistant to Glyphosate. Ten inbred-cultivated rice varieties (Bg250, Bg94-1, Bg304, Bg359, Bg406, Bg379-2, Bg366, Bg300, Bw364, At362) and three traditional rice varieties ("Kalu Heenati", "Sudu Heenati", "Pachchaperumal") were naturally resistant to 0.25 g L(-1) Glyphosate concentration and when increased the concentration (0.5 g L(-1)) resistance was reduced. This study showed the usefulness of modern statistical method, classification and regression tree analysis (CART) in exploring and visualizing the patterns reflected by a large number of rice varieties (larger experimental database) on herbicide resistance in future.

  19. Natural herbicide resistance (HR) to broad-spectrum herbicide, glyphosate among traditional and inbred-cultivated rice (Oryza sativa L.) varieties in Sri Lanka.

    Science.gov (United States)

    Weerakoon, S R; Somaratne, S; Wijeratne, R G D; Ekanyaka, E M S I

    2013-08-15

    Weeds along with insect pests and plant diseases are sources of biotic stress in crop systems. Weeds are responsible for serious problems in rice worldwide affecting growth and causing a considerable reduction in quality and quantity in yield. High concentrations of pre-emergent-broad-spectrum systemic herbicide, Glyphosate is prevalently applied to control rice weeds which intern causes severe damages to cultivated rice varieties, susceptible to Glyphosate. However, there may be rice varieties with natural Herbicide Resistance (HR) which are so far, has not been evaluated. In this study Six traditional and eighteen developed-cultivated rice varieties (Bg, Bw, At and Ld series developed by Rice Research Development Institute, Sri Lanka) were used to screen their natural HR. RCBD with five replicates and three blocks in each treatment-combination was used as the experimental design. As observations, time taken-to seed germination, time taken to flowering; plant height and number of leaves at 12-weeks after sawing, leaf-length, breadth, panicle-length, number of seeds/panicle of resistant plants and controls were recorded. Plants with > or = 40% resistance were considered as resistant to Glyphosate. Ten inbred-cultivated rice varieties (Bg250, Bg94-1, Bg304, Bg359, Bg406, Bg379-2, Bg366, Bg300, Bw364, At362) and three traditional rice varieties ("Kalu Heenati", "Sudu Heenati", "Pachchaperumal") were naturally resistant to 0.25 g L(-1) Glyphosate concentration and when increased the concentration (0.5 g L(-1)) resistance was reduced. This study showed the usefulness of modern statistical method, classification and regression tree analysis (CART) in exploring and visualizing the patterns reflected by a large number of rice varieties (larger experimental database) on herbicide resistance in future. PMID:24498832

  20. Influence of Crop Nutrition on Grain Yield, Seed Quality and Water Productivity under Two Rice Cultivation Systems

    Institute of Scientific and Technical Information of China (English)

    Y.V.SINGH; K.K.SINGH; S.K.SHARMA

    2013-01-01

    The system of rice intensification (SRI) is reported to have advantages like lower seed requirement,less pest attack,shorter crop duration,higher water use efficiency and the ability to withstand higher degree of moisture stress than traditional method of rice cultivation.With this background,SRI was compared with traditional transplanting technique at Indian Agricultural Research Institute,New Delhi,India during two wet seasons (2009-2011).In the experiment laid out in a factorial randomized block design,two methods of rice cultivation [conventional transplanting (CT) and SRI] and two rice varieties (Pusa Basmati 1 and Pusa 44) were used under seven crop nutrition treatments,viz.T1,120 kg/hm2 N,26.2 kg/hm2 P and 33 kg/hm2 K; T2,20 t/hm2 farmyard manure (FYM); T3,10 t/hm2 FYM + 60 kg/hm2 N; T4,5 t/hm2 FYM + 90 kg/hm2 N; T5,5 t/hm2 FYM + 60 kg/hm2 N + 1.5 kg/hm2 blue green algae (BGA); T6,5 t/hm2 FYM + 60 kg/hm2 N + 1.0 t/hm2 Azolla,and T7,N0P0K0 (control,no NPK application) to study the effect on seed quality,yield and water use.In SRI,soil was kept at saturated moisture condition throughout vegetative phase and thin layer of water (2-3 cm) was maintained during the reproductive phase of rice,however,in CT,standing water was maintained in crop growing season.Results revealed that CT and SRI gave statistically at par grain yield but straw yield was significantly higher in CT as compared to SRI.Seed quality was superior in SRI as compared to CT.Integrated nutrient management (INM) resulted in higher plant height with longer leaves than chemical fertilizer alone in both the rice varieties.Grain yield attributes such as number of effective tillers per hill,panicle length and panicle weight of rice in both the varieties were significantly higher in INM as compared to chemical fertilizer alone.Grain yields of both the varieties were the highest in INM followed by the recommended doses of chemical fertilizer.The grain yield and its attributes of Pusa 44 were significantly

  1. The Character of Rice Cultivation in Heilongjiang Province and Production of Green Rice Food%黑龙江省稻作特点与绿色稻米食品生产

    Institute of Scientific and Technical Information of China (English)

    李霞辉; 李辉; 任洪波

    2001-01-01

    In this paper, according to the character of high latitude rice cultivation in Heilongjiang province, the restrict factors influencing rice quality and taste were demonstrated and some suggestion to develop green rice industry were put forward.%依据黑龙江省高纬度稻作区特点,重点论述影响米质与食味的制约因素,提出发展绿色稻米产业的一些建议。

  2. Fine Mapping of Spr3,a Locus for Spreading Panicle from African Cultivated Rice(Oryza glaberrima Steud.)

    Institute of Scientific and Technical Information of China (English)

    Ji-Jing Luo; Wei Hao; Jian Jin; Ji-Ping Gao; Hong-Xuan Lin

    2008-01-01

    A CSSL(chromosome segment substitution line),SG-64,carrying a segment of chromosome 4 from African cultivated rice(CG-14)in the genetic background of vat.Wuyujing-7(japonica),showed a spreading panicle,which was different significantly from that of Wuyujing-7 with an erect compact panicle.The gene controlling a spreading panicle is referred to as Spr3,and is mapped on chromosome 4.To uncover the genetic basis of Spr3,a large F2 population derived from cross between SG-64 and Wuyujing-7 was constructed for fine mapping of the Spr3 locus.The high-resolution linkage analysis revealed that the Spr3 locus was narrowed down to a 4.6-kb region.The delimited genomic DNA regions of Wuyujing-7 and CG.14 were sequenced and compared.Sequence mutations between Wuyujing-7 and CG-14 were evident and the candidate genes for the locus were predicted.Publicly available databases were searched for homologous cDNA sequences.However,any coding regions or other meaningful sequences for the Spr3 locus were not found within this delimited region.This result suggested that Spr3 is an unknown genetic factor in controlling the outspreading of the primary branches in rice inflorescence.In addition.NIL(Spr3)exhibited seed shattering.The formation of spreading panicle was accompanied by a few undesirable traits and the spreading panicle links with seed shattering suggest that the spreading panicle was likely Iost during the domestication and selection for high seed productivity of cultivated rice.

  3. Mating Type Alleles,Female Fertility and Genetic Diversity of Magnaporthe grisea Populations Pathogenic to Rice from Some Asian Countries

    Institute of Scientific and Technical Information of China (English)

    SHEN Ying; Joelle Milazzo; YUAN Xiao-ping; Henry Adreit; WANG Yan-li; Jean Loup Notteghem; Didier Tharreau

    2003-01-01

    Five hundred and twenty-two isolates of Magnaporthe grisea isolated from rice in 5 Asian countries were characterized for their mating type by crossing them with 4 hermaphroditic isolates (KA3 and TH2: MAT1.1; Guy11 and TH-16: MAT1.2). Among them, 41% were MAT1.1 and 25% were MAT1.2.The remaining 34% did not produce perithecia with any of the 4 hermaphroditic testers. In Bangladesh, India,Nepal, Vietnam and in most provinces of China, both mating types were present. Only one mating type was found in 3 provinces and 1 city of China. Almost all the isolates had very low fertility, as they were in general female sterile and sometimes also male sterile. Hermaphroditic isolates were recovered from the 5 countries. In these countries, they represented between 13% and 75% of the isolates. In Zhejiang, Guizhou, Guangdong,Hunan, Yunnan and H-ubei provinces of China, hermaphroditic isolates represented between 6% and 67%.The genetic diversity of 143 isolates from these countries and provinces, where hermaphroditic isolates had been collected, was analyzed using SCAR markers. Genetic diversity was high and population structure did not resemble classical clonal structure described in most rice growing regions. The existence of sexual reproduction in the field, localization of a center of diversity in China, and migration between countries were discussed in this paper.

  4. Arsenic translocation in rice cultivation and its implication for human health

    Directory of Open Access Journals (Sweden)

    José M Bastías

    2016-03-01

    Full Text Available Arsenic (As is a toxic metalloid for plants and animals. Large amounts of As have been released in arable soils through anthropogenic activities, use of contaminated irrigation water, and mining among others. Rice (Oryza sativa L. is one of the most consumed cereals worldwide; it is an important route of exposure for As. The objective of this review was to explain possible mechanisms involved in As absorption that contaminate rice plant through the soil and water, and to mention studies that have been conducted to minimize the risk of human exposure. The root is able to absorb and accumulate large amounts of As, but only small amounts are translocated to the grain and tillers. Arsenic concentrations in rice tissues decrease from the root to the grain. Information about As translocation in rice is sparse and research is directed toward studying the molecular mechanism of absorption and accumulation in the grain because it has not yet been explained. Some rice varieties have been developed that are resistant to high soil As concentrations and are not able to translocate the metalloid toward the root. Many studies suggest that not all ingested inorganic As accumulated in the gastrointestinal tract is absorbed into the bloodstream and produces toxicity. It is therefore recommended that As bioavailability be evaluated in imported or domestic Chilean rice to more precisely estimate human health risk

  5. Heavy metal toxicity in rice and soybean plants cultivated in contaminated soil

    Directory of Open Access Journals (Sweden)

    Maria Lígia de Souza Silva

    2014-04-01

    Full Text Available Heavy metals can accumulate in soil and cause phytotoxicity in plants with some specific symptoms. The present study evaluated the specific symptoms on rice and soybeans plants caused by excess of heavy metals in soil. Rice and soybean were grown in pots containing soil with different levels of heavy metals. A completely randomized design was used, with four replications, using two crop species and seven sample soils with different contamination levels. Rice and soybean exhibited different responses to the high concentrations of heavy metals in the soil. Rice plants accumulated higher Cu, Mn, Pb and Zn concentrations and were more sensitive to high concentrations of these elements in the soil, absorbing them more easily compared to the soybean plants. However, high available Zn concentrations in the soil caused phytotoxicity symptoms in rice and soybean, mainly chlorosis and inhibited plant growth. Further, high Zn concentrations in the soil reduced the Fe concentration in the shoots of soybean and rice plants to levels considered deficient.

  6. Metabolomic quality control of commercial Asian ginseng, and cultivated and wild American ginseng using (1)H NMR and multi-step PCA.

    Science.gov (United States)

    Zhao, Huiying; Xu, Jin; Ghebrezadik, Helen; Hylands, Peter J

    2015-10-10

    Ginseng, mainly Asian ginseng and American ginseng, is the most widely consumed herbal product in the world . However, the existing quality control method is not adequate: adulteration is often seen in the market. In this study, 31 batches of ginseng from Chinese stores were analyzed using (1)H NMR metabolite profiles together with multi-step principal component analysis. The most abundant metabolites, sugars, were excluded from the NMR spectra after the first principal component analysis, in order to reveal differences contributed by less abundant metabolites. For the first time, robust, distinctive and representative differences of Asian ginseng from American ginseng were found and the key metabolites responsible were identified as sucrose, glucose, arginine, choline, and 2-oxoglutarate and malate. Differences between wild and cultivated ginseng were identified as ginsenosides. A substitute cultivated American ginseng was noticed. These results demonstrated that the combination of (1)H NMR and PCA is effective in quality control of ginseng. PMID:26037159

  7. Rice re-cultivation in southern China:An option for enhanced climate change resilience in rice production%中国南方调整水稻种植格局——一种水稻生产预先适应气候变化的选择

    Institute of Scientific and Technical Information of China (English)

    MA Xin; WU Shaohong; LI Yu'e; ZHANG Xueyan; GAO Qingzhu; WU Yang

    2013-01-01

    @@%Rice planted in southern China accounts for 94% of the total in sown acreage and 88% of the total in production,which matters a lot to Chinese food security.However,due to the prolonged conflict between water availability and rice growth in spatial/temporal distribution,rice production suffers from seasonal drought at acreage of 16%-22%,which compromises food production capacity and food security.Focusing on the spatial distribution of seasonal drought with rice and the practices to adapt to it,and based on an analysis of balanced water supply for and demand by rice at a growing season scale during 1981-2030,this paper assesses the changing seasonal drought in the process of rice production under the changing climate in the future,and identifies general rice re-cultivation options for climate change adaptation.Some conclusions can be drawn as follows.(1) Rice suggests a decline in seasonal drought,with early season rice (early rice hereafter) by 12,500 km2,middle season rice (middle rice) by 80,000 km2,and in particular late season rice (late rice) by 25,000 km2,which accounts for almost 20% of its cultivated acreage.It is indicated that due to climate change,seasonal drought in major rice producing areas tends to alleviate in general,late season rice in particular.(2) Future climate change brings about a significant impact on the spatial/temporal distribution of water resources in rice producing areas in China.Based on 'pre-designed' adaptation actions for rice-re-cultivation,the rice cultivation pattern undergoes a significant alteration between 1981-2000 and 2001-2030.In eastern Guizhou and western Hunan,the pattern of single early plus single dry farming is changed into double cropping.In eastern Hunan,the pattern of dry cropping is changed into single early plus single dry farming.In northern Anhui,the pattern of dry farming cropping is changed into middle rice.All this is aimed at a potential adequate availability of water for rice production in

  8. Effects of cultivation conditions on the diversity of microbes involved in the conversion of rice straw to fodder

    Institute of Scientific and Technical Information of China (English)

    YANG Hong-yan; GAO Li-juan; WANG Xiao-fen; WANG Wei-dong; CUI Zong-jun

    2007-01-01

    To confirm the optimum cultivation conditions for analyzing lactic acid bacterial communities and to provide the cultivation foundation for lactic acid bacterial communities that were used to convert straw into fodder, fermented rice straw was inoculated into 13 different broths. After 48 h of cultivation, pH values, volatile products, and microbial diversity were analyzed. Except for LAB broth, the pH values of the other broths could decrease to approximately 4.5. GC/MS analysis showed that lactic acid in Tomato MRS broth, MRS broth, LAB broth, and Tomato juice broth was higher than that in the other broths. DNA concentration analysis showed that the counts of microbes in Tomato MRS broth were 2.5 times higher than those in other broths and that tomato juice favored the reproduction of the microbes. Denaturing gradient gel electrophoresis (DGGE) analysis showed that the number of lactic acid bacterial species in HYA broth, Tomato juice broth, and Tomato MRS broth were higher than those in the other broths.

  9. Greenhouse gas emissions, soil quality, and crop productivity from a mono-rice cultivation system as influenced by fallow season straw management.

    Science.gov (United States)

    Liu, Wei; Hussain, Saddam; Wu, Lishu; Qin, Ziguo; Li, Xiaokun; Lu, Jianwei; Khan, Fahad; Cao, Weidong; Geng, Mingjian

    2016-01-01

    Straw management during fallow season may influence crop productivity, soil quality, and greenhouse gas (GHG) emissions from rice field. A 3-year field experiment was carried out in central China to examine the influence of different fallow season straw management practices on rice yield, soil properties, and emissions of methane (CH4) and nitrous oxide (N2O) from a mono-rice cultivation system. The treatments comprised an unfertilized control (CK), inorganic fertilization (NPK), rice straw burning in situ (NPK + RSB), rice straw mulching (NPK + RSM), and rice straw strip mulching with green manuring (NPK + RSM + GM). The maximum rice yield, soil organic carbon, soil total nitrogen, and available potassium were observed in NPK + RSM + GM treatment. Compared with NPK, the NPK + RSM + GM recorded 9% higher grain yield averaged across 3 years. However, NPK + RSM and NPK + RSB were statistically similar with NPK regarding grain yield. The NPK + RSM and NPK + RSM + GM recorded significantly higher CH4 emission during rice growing season as well as winter fallow; however, the response of N2O emissions was variable. The NPK + RSM and NPK + RSM + GM were statistically similar for annual cumulative CH4 and N2O emissions. The NPK + RSM + GM recorded 103 and 72% higher straw-induced net economic benefits and soil organic carbon sequestration rate, and reduced net global warming potential by 27% as compared with NPK + RSM. Considering the benefits of soil fertility, higher crop productivity, and environmental safety, the NPK + RSM + GM could be the most feasible and sustainable option for mono-rice cultivation system in central China. PMID:26304808

  10. Utilization of composted sugar industry waste (pressmud) to improve properties of sodic soil for rice cultivation.

    Science.gov (United States)

    Seth, Rashi; Chandra, R; Kumar, Narendra; Tyagi, A K

    2005-07-01

    Sulphitation pressmud (SPM) and its composts were prepared by heap, pit, NADEP and vermicomposting methods and their effects were compared with soil properties and growth, yield and nutrient uptake by rice in a sodic soil under pot conditions. Application of 15 t ha(-1) SPM and its different composts significantly increased the plant height and dry matter accumulation at different intervals, grain and straw yields and N, P and K uptake by the crop over the control. NADEP compost of SPM alone recorded the maximum and significant plant height by 8.5 to 19.3% and plant dry matter by 14.6 to 32.8% over the raw SPM at different intervals. NADEP composts of SPM alone and SPM + rice straw were also found to be superior than raw SPM by recording 34.8 and 27.8% more grain yield respectively. The SPM composts prepared by NADEP and SPM by vermicomposting methods significantly accumulated higher N and K in rice grains and straw, while NADEP compost of SPM and SPM + rice straw recorded more P in grains and straw than raw SPM. Application of SPM and its composts reduced the pH, EC and bulk density of the soil after rice harvesting, though the reductions were not significant in comparison to the control. However, these treatments increased the soil organic C by 33.33 to 69.0%, available N by 41.4 to 74.8%, available P by 47.1 to 97.8%, available K by 11.8 to 59.2% and available S by 10.3 to 90.7% over the control. NADEP composts, in general, were found to be superior than the raw SPM and other composts in residual soil nutrient content after rice crop.

  11. Resequencing 50 accessions of cultivated and wild rice yields markers for identifying agronomically important genes

    DEFF Research Database (Denmark)

    Xu, Xun; Liu, Xin; Ge, Song;

    2012-01-01

    raw data coverage. We investigated genome-wide variation patterns in rice and obtained 6.5 million high-quality single nucleotide polymorphisms (SNPs) after excluding sites with missing data in any accession. Using these population SNP data, we identified thousands of genes with significantly lower...

  12. From flooded to aerobic conditions in rice cultivation: consequences for zinc uptake

    NARCIS (Netherlands)

    Gao, X.; Zou, C.; Fan, X.; Zhang, F.S.; Hoffland, E.

    2006-01-01

    Scarcity of water causes a shift from flooded to aerobic conditions for rice production in zinc deficient areas in Northern China. This shift alters soil conditions that affect zinc availability to the crop. This paper concerns the effect of aerobic compared to flooded conditions on crop biomass pro

  13. Comparison of Genetic Diversity Between Local Cultivated Aromatic and Non-aromatic Rice in Yunnan Province%云南地方香稻与非香稻遗传多样性比较

    Institute of Scientific and Technical Information of China (English)

    白现广; 程在全; 蔺忠龙; 吕广磊; 黄兴奇

    2009-01-01

    [Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice.[Method] Genetic diversity of 10 aromatic rice and 45 non-aromatic rice were analyzed by 64 SSR primers covered on 12 rice chromosomes. [Result] Per locus 5.44 and 7.98 alleles in average were detected, ranging from 2 to 12 and from 2 to 17 in aromatic and non-aromatic rice , respectively. Average genetic multiplicity index(Hs) was 0.46 and 0.67 respectively. The average polymorphism information content (PIC) was 0.43 and 0.58 in aromatic and non-aromatic rice respectively.[Conclusion] The results indicated that genetic diversity was higher in non-aromatic rice than in aromatic rice.

  14. The temporal and spatial distribution of ancient rice in China and its implications

    Institute of Scientific and Technical Information of China (English)

    GONG ZiTong; CHEN HongZhao; YUAN DaGang; ZHAO YuGuo; WU YunJin; ZHANG GanLin

    2007-01-01

    The relics of ancient rice have been regarded as the most important objective evidence of the origination and spread of rice cultivation. Based on the records of 280 rice relics sites and the rice cropping regionalization as well as the distribution map of paddy soils, the current study compiled the temporal and spatial distribution map of ancient rice distribution in China. The map shows that the distribution of ancient rice is spatially extensive and meantime comparatively concentrated, temporarily covering a long and relatively continuous time-span. The rice relics in the Central China double and single rice cropping regions are among the earliest and the most abundant ones, possessing continuity in time sequence. Combined with the discovery of ancient rice and paddy filed relics, soil micromorphology,pollen combination and element geochemistry, it is suggested that Central China was the origin center of rice cultivation in China. Rice had been spread to the rest part of China in three major waves, also to the East Asian part like Korea and Japan. The temporal and spatial distribution of ancient rice reflects the past environmental change, which is also meaningful to the current rice regionalization and planning as well as food security in China.

  15. Rice Root Architectural Plasticity Traits and Genetic Regions for Adaptability to Variable Cultivation and Stress Conditions.

    Science.gov (United States)

    Sandhu, Nitika; Raman, K Anitha; Torres, Rolando O; Audebert, Alain; Dardou, Audrey; Kumar, Arvind; Henry, Amelia

    2016-08-01

    Future rice (Oryza sativa) crops will likely experience a range of growth conditions, and root architectural plasticity will be an important characteristic to confer adaptability across variable environments. In this study, the relationship between root architectural plasticity and adaptability (i.e. yield stability) was evaluated in two traditional × improved rice populations (Aus 276 × MTU1010 and Kali Aus × MTU1010). Forty contrasting genotypes were grown in direct-seeded upland and transplanted lowland conditions with drought and drought + rewatered stress treatments in lysimeter and field studies and a low-phosphorus stress treatment in a Rhizoscope study. Relationships among root architectural plasticity for root dry weight, root length density, and percentage lateral roots with yield stability were identified. Selected genotypes that showed high yield stability also showed a high degree of root plasticity in response to both drought and low phosphorus. The two populations varied in the soil depth effect on root architectural plasticity traits, none of which resulted in reduced grain yield. Root architectural plasticity traits were related to 13 (Aus 276 population) and 21 (Kali Aus population) genetic loci, which were contributed by both the traditional donor parents and MTU1010. Three genomic loci were identified as hot spots with multiple root architectural plasticity traits in both populations, and one locus for both root architectural plasticity and grain yield was detected. These results suggest an important role of root architectural plasticity across future rice crop conditions and provide a starting point for marker-assisted selection for plasticity. PMID:27342311

  16. Practice of Factory Cultivation Technology for Mechanical Transplantation of Rice%水稻机插秧工厂化育秧技术实践

    Institute of Scientific and Technical Information of China (English)

    朱忠初; 姚林泉; 谢金元

    2015-01-01

    水稻工厂化育秧是水稻机插秧推广的关键配套技术。工厂化育秧从种子处理到生产管理实现全程机械化,使育秧达到了集约化、规格化、标准化,同时人工环境为培育机插秧所需求的壮秧创造了良好条件。工厂化育秧的技术要点是营养土准备、精量播种及肥水管理与病虫害防治,同时要特别注意控温、增光与通风等。%Factory cultivation of rice is a crucial supporting technology for the promotion of mechanical transplantation of rice.the process of factory cultivation of rice,from the processing of seeds to the achievement of the complete mechanization of production management,makes the cultivation become intensive,normalized and standardized,and the artificial environment creates sound conditions needed when cultivatingstrong seeding through mechanical transplantation. The important points of factory cultivation are the preparation of nutrient soil,proper and precise seeding and the management of nutrient water,control and prevention of diseases and pests,and attention shall be paid to the control on temperature,illumination and ventilation,etc.

  17. Identifying neutral allele Sb at pollen-sterility loci in cultivated rice with Oryza rufipogon origin

    Institute of Scientific and Technical Information of China (English)

    SHI LeiGang; LIU XiangDong; LIU Bo; ZHAO XingJuan; WANG Lan; LI JinQuan; LU YongGen

    2009-01-01

    Pollen sterility is commonly found in the intra-specific hybrids of indica and japonica rice, which is one of the main constrains for the utilization of heterosis between indica and japonica. Six loci controlling the pollen sterility of F1 between indica and japonica have been identified from previous studies. Neu-tral alleles at each locus are potential to overcome the F1 pollen sterility associated with the locus. Therefore, exploitation and utilization of neutral alleles are of significant importance. The present re-search was based on fine mapping of the F_1 pollen-sterility gene Sb and the abundant genetic diversity of Oryza rufipogon Griff. indigenous to Gaozhou, Guangdong Province (referred to as Gaozhou wild rice). Crosses were made using Taichung65 (with the genotype of S_b~jS_b~j and referred to as E_1) and its near-isogenic line of F_1 pollen sterility gene Sb(with the genotype of S_b~iS_b~i, E_2) as female parents, and 12 different accessions of Gaozhou wild rice as male parents. F_1 pollen fertility was examined to identify the materials having the neutral alleles at the F_1 pollen-sterility locus. Segregation of 4 molecular markers tightly linked with the Sb locus was analyzed in the F_2 populations derived from the F_1s car-rying the neutral gene. The pollen fertility related to the 3 genotypes of the molecular markers was also checked by statistical test to determine whether it was consistent with the hypothesis. The results showed that the pollen fertility of two F_1s from one accession of Gaozhou wild rice (GZW099) with E_1 and E_2 was (89.22±1.07)% and (85.65±1.05)%, respectively. Both of them were fertile and showed no significant difference by t-test. Segregation of the 3 genotypes of the 4 molecular markers followed the expected Mendelian ratio (1:2:1) in the F_2 populations. There was no significant difference for the av-eraged pollen fertility of the plants related to the 3 genotypes, suggesting that no interaction exists between the

  18. 蚕豆—甜玉米—晚稻高产栽培技术%High-yielding cultivation techniques of broad bean, sweet corn, late rice

    Institute of Scientific and Technical Information of China (English)

    陈光敏

    2012-01-01

    总结了蚕豆—甜玉米—晚稻高产栽培技术,包括选用良种、合理轮作、种植规格、育苗、田间管理、病虫防治、适时收获等技术内容,为该栽培模式的推广应用提供参考。%Summaried high-yielding cultivation techniques of broad bean, sweet corn, late rice, including the selection of goodvarieties, reasonable rotation, cultivation, breeding specifications, field management, pest control, harvesting timing.

  19. High-yielding Cultivation Techniques of Hybrid Rice after Cropping of Tobacco%建阳市烟后稻高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    吴隆灿; 陈燕萍

    2013-01-01

    通过对建阳市烟后稻高产栽培方式的分析,介绍了建阳市烟后稻高产栽培模式的关键技术:选择适宜作烟后稻品种,培育壮苗,大田管理与病虫害防治等。%According to analysis of high-yielding cultivation techniques of rice after cropping of tobacco, we introduced planting performance and high-yielding cultivation techniques after cropping of tobacco in this paper, which contained suitable rice varieties, breeding strong seedling, field management, and disease and insect control.

  20. Allele Types ofRcGene of Weedy Rice from Jiangsu Province, China

    Institute of Scientific and Technical Information of China (English)

    LIXiao-yan; QIANGSheng; SONGXiao-ling; CAIKun; SUNYi-na; SHIZhi-hua; DAIWei-min

    2014-01-01

    Weedy rice(Oryza sativaf.spontanea), the predominant type of which has a red pericarp, seriously inhibits growth and yield of direct-seeded rice in Jiangsu Province, China. In this study, we randomly selected 10 weedy rice accessions from 10 plots in Jiangsu, and then sequenced the full lengths of theirRcgenes (approximately 6.4 kb). In addition, we collected 166 different full-lengthRc genes in theOryzagenus from the literature and from GenBank. A collinearity sequence analysis showed that the 10 weedy riceaccessions from Jiangsu all had the same wild-type allele of theRcgene. Single nucleotide polymorphisms indicated thatthe nucleotide polymorphisms (π= 0.19) and theproportion of segregation sites(θw= 0.28) of theRcgenes in the 10 weedy rice accessions from Jiangsu were higher than those in 56 weedy rice accessions from USA (π= 0.09 andθw= 0.07). Haplotype and phylogenetic analyses showed thattheRcgenes of weedy rice accessions from Jiangsu were not revertants of therc gene found in Asian cultivated rice(O. sativa) varietieswith white pericarp. In addition,Rcgene sequences of the rice varieties Lvdao from Lianyungang, Jiangsu and Tangdao from Anhui were more similar to those of cultivated rice than to the weedy rice from Jiangsu. These findings support the continued quarantine of weedy rice and clarify the evolutionary mechanism of the red pericarp found in the weedy rice of Jiangsu.

  1. Key Throwing-seedling Cultivation Techniques of Post-tobacco Super Rice%烟后超级稻抛秧栽培关键技术

    Institute of Scientific and Technical Information of China (English)

    王朝清

    2012-01-01

    针对烟稻轮作和抛秧的特点,提出了烟后超级稻抛栽要因地制宜,选好稻种,合理安排播种期,采用塑料软盘培育壮秧,合理的抛栽密度,促控高产群体生长,病虫害综合防治等高产栽培技术。%According to the characteristics of tobacco-rice rotation and throwing-seedling, the paper put forward to some high-yielding cultivation techniques by throwing-seedling for post-tobacco super rice with adjusting measures to local conditions, such as selecting fine hybrid rice seed, arranging suitable sowing time, raising healthy and robust seedling based on plastic soft-plate with holes, reasonable planting density, accommodating high-yielding population growth, and the integration of pest control.

  2. PROGRESS IN STUDIES ON RICE QUALITY-RETAINING CULTIVATION TECHNIQUES OF HIGH-QUALITY RICE VARIETIES%优质稻保优栽培技术的研究进展(综述)

    Institute of Scientific and Technical Information of China (English)

    曹黎明; 袁勤; 倪林娟; 吴月兰

    2001-01-01

    综述了温、光等环境因子和肥、水、病、虫等栽培因子对优质水稻品质形成的影响。阐述了在栽培中如何通过合理安排播种期、运筹肥水、防治病虫害等措施保持优质稻的优质特性。%Several environmental factors such as temperature and light and cultural factors such as fertilizers and water management and pest control which influence the formation of rice quality were reviewed. The authors also relate in the paper the hows of rationally fixing sowing date, operating fertilizer and water management and practicing pest control in cultivation of high-quality rice varieties with the aim of producing quality rice retaining good qualitative traits.

  3. A study of rice cultivation aimed at reducing biocide with increased yield by the regulation of micrometeorological factors

    International Nuclear Information System (INIS)

    A possibility of paddy rice (Oryza sativa) cultivation with reflective mulching materials as a tool of low input and high-yielding culture was examined. The albedo increased and water temperature in the daytime decreased by mulching of white styrofoam board or reflective film over the interrow space. Leaf area indexes in the mulching plots decreased as compared to the control plot due to the decline in leaf weight ratio and the increase in specific leaf weight. By mulching, the dry matter production at early growth stage increased in a year 1999 under relatively low sunshine but it tended to decrease in another year 2000 under intense sunshine, high temperature and low humidity. Furthermore, dry matter production in the latter half of growth tended to increase in both years, and the percentage of ripened grains elevated as well as the number of ripened grains. In both years, the grain yield increased about 10% and the damage due to grass leaf roller (Cnaphalocrocis medinalis) reduced, by mulching

  4. Genotypic Differences in Growth and Physiological Responses to Transplanting and Direct Seeding Cultivation in Rice

    Institute of Scientific and Technical Information of China (English)

    CHEN Song; CAI Sheng-guan; CHEN Xin; ZHANG Guo-ping

    2009-01-01

    The field experiments were conducted to investigate the growth and physiological responses of six super hybrid rice combinations to two planting methods, transplanting (TP) and direct seeding (DS) during 2006-2007 and 2007-2008. The 1000-grain weight and number of tillers per plant at the early growth stage, the maximum quantum yield of PSII (Fv/Fm) and transpiration rate (Tr) were higher in DS plants than in TP ones, whereas the grain yield, number of panicles per square meter, seed setting rate, net photosynthetic rate (Pn) and stomatal conductance were lower in DS plants. However, little difference was detected in number of grains per panicle, stem (shoot) and leaf weight between the combinations in the two planting methods. The responses of plant growth and physiological traits to planting method differed greatly among the six combinations. In both planting methods, Chouyou 58 and Yongyou 6 had the highest and lowest panicle biomass and Pn, respectively. The higher yield of Chunyou 58 was associated with more numbers of panicles per square meter and grains per panicle in both planting methods. The results indicate that lower grain yield in DS relative to TP is attributed to more excessive tillers at the early stage, lower leaf biomass and photosynthetic rate at the late stage.

  5. Review paper on the production trials of rice-cum fish culture - a transferable concept into Niger State, Nigeria

    OpenAIRE

    Yaro, I.

    1999-01-01

    This paper reviews the production trials of rice-cum-fish culture. Rice and various fish species using rotation and concurrent methods of cultivation are used. The farming system is mostly practiced and researched in to in Southeast Asian countries. It addresses the problems of high external inputs, sustainable aquaculture, poverty and nutrition in the rural population, insect pests, use of insecticides, weeds control and under-utilization of agricultural lands. The production trials yields a...

  6. Temporary wetland restoration after rice cultivation: is soil transfer required for aquatic plant colonization?

    Directory of Open Access Journals (Sweden)

    Muller I.

    2013-09-01

    Full Text Available Mediterranean temporary wetlands have considerably declined in recent decades. Today, opportunities arise for the restoration of these wetlands due to land-use changes, such as the abandonment of cultivation. One critical question is whether communities, such as those observed in natural temporary wetlands, can develop alone or if active restoration should be implemented. In a series of experimental mesocosms, we transferred soil from several temporary wetlands chosen as a set of reference ecosystems. Four months after soil transfer, vegetation in transfer mesocosms was compared to that derived from spontaneous colonization (control mesocoms. Transfer mesocosms are colonized by all target hydrophyte species transferred with the soil and the resulting communities are similar to those of reference ecosystems. They also have fewer non-target species than the control mesocosms. Even though the study period was not sufficient to draw any definitive conclusion regarding the utility of forced dispersion by soil transfer, the preliminary results are promising for an application on a larger scale.

  7. Effects of Land Management Practices on Labile Organic Carbon Fractions in Rice Cultivation

    Institute of Scientific and Technical Information of China (English)

    SHAO Jing'an; LI Yangbing; WEI Chaofu; XIE Deti

    2009-01-01

    A research trial with four land management practices, I.e., traditional tillage-fallow (TTF), traditional till-age-wheat (TTW), conservation tillage-fallow (CTF) and conservation tillage-wheat (CTW), was sampled in the 15th year after its establishment to assess the effects of different management practices on labile organic carbon fractions (LOCFs), such as easily oxidizable organic carbon (EOC), dissolved organic carbon (DOC), particulate organic carbon (POC) and microbial biomass carbon (MBC) in a typical paddy soil, Chongqing, Southwest China. The results indi-cated that LOCFs were significantly influenced by the combination of no-tillage, ridge culture and crop rotation. And,different combination patterns showed different effectiveness on soil LOCFs. The effects of no-tillage, ridge culture and wheat cultivation on EOC, DOC, POC and MBC mainly happened at 0-10cm. At this depth, soil under CTW had higher EOC, DOC, POC and MBC contents, compared to TTF, TTW and CTF, respectively. Moreover, the contents of LOCFs for different practices generally decreased when the soil depth increased. Our findings suggest that the paddy soil in Southwest China could be managed to concentrate greater quantities of EOC, DOC, POC and MBC.

  8. 粉垄栽培对水稻产量和品质的影响%Effect of Fenlong Cultivation on Yield and Quality of Rice

    Institute of Scientific and Technical Information of China (English)

    韦本辉; 刘斌; 甘秀芹; 申章佑; 胡泊; 李艳英; 吴延勇; 陆柳英

    2012-01-01

    [目的]探索农耕新方法粉垄栽培水稻的可行性及其对水稻产量和品质的影响.[方法]以Y两优1号,汕小占为供试材料,传统翻耕浆耙栽培为对照(CK),进行早稻粉垄栽培和晚稻免耕抛秧栽培试验,对相关性状和产量、品质进行调查和测定;并对粉垄后第三造轻耕种植水稻的产量及土壤的紧实度进行调查.[结果]粉垄栽培与CK相比,早造粉垄稻田耕层厚度加深7 cm,土壤速效养分多数指标增加10%以上,水稻总根数量及白根数量分别增加14.83%-25.36%、20.18%-97.78%,稻株生物产量增加29.96%-31.89%,结实率增加7.62%,稻谷产量增加23.87%,整精米率、蛋白质分别增加15.95%、14.61%;晚造免耕抛秧比CK的总根数量和白根数量分别增加6.02%-22.75%、48.03%-65.91%,产量增加9.25%,整精米率、蛋白质分别增加7.43%、5.61%;早晚两造合计增产16.48%,增加收入6 706.5元/hm2;粉垄后第三造轻耕种植水稻收获时耕作层土壤的紧实度比对照降低68.00%-333.33%,产量增加7.97%.[结论]粉垄栽培水稻,当造和后一造免耕均可行,均能提高稻谷产量和改善稻米品质,增加纯收益;粉垄后第三造仍能提高稻谷产量,粉垄后稻田具有持续增产能力.%[Objective] The feasibility of the new farming method of Fenlong cultivation for rice, and its effects on yield and quality of rice were studied. [Method] YLiangyoul and Shanxiaozhan were used as materials in the test, the traditional ploughing with rake was used as CK, and smash-ridging cultivated early rice and no-tillage of late rice were carried out to investigate the related characters, yield and quality of rice. The yield of the third time planted rice after Fenlong and soil compactness were investigated. [Result] Compared with the traditional cultivation, Fenlong planted early rice increased the plough layer by 7 cm, most indicators of soil available nutrients increased by

  9. On-farm Conservation of Landraces of Rice (Oryza Sativa L.) through Cultivation in the Kumaun Region of Indian Central Himalaya

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Himalayan region is a known hot spot of crop diversity. Traditional varieties (usually called primitive cultivars or landraces), having withstood the rigors of time (including harsh climatic conditions as well as attacks of insects, pests and diseases), can still be found in crop fields in rural parts of Indian Central Himalaya (ICH). These landraces harbor many desired traits from which, for example, varieties that are tolerant/resistant to abiotic/biotic stresses could be developed. In addition to the above benefits,landraces provide a basis for food security and a more varied and interesting diet. Some landraces are also known to be of medicinal value. These, along with some lesser known hill crops, are often referred to by different names such as under exploited crops, crops for marginal lands, poor person crops, and neglected mountain crops. The Himalayan region continues to be a reservoir of a large number of landraces and cultivars whose economic and ecological potential is yet to be fully understood and/or exploited. Indians have had a history of rice cultivation since ancient times. Farmers, including tribals inhabiting the IHR, still cultivate a plethora of landraces of rice and thus directly contribute towardson-farm conservation of valuable germplasm and help in the preservation of crop diversity. The present paper looks at the on-farm conservation of rice germplasm, which is still practised in the Kumaun region of ICH.

  10. 不同水稻种植模式对氮磷流失特征的影响%Effects of rice cultivation patterns on nitrogen and phosphorus leaching and runoff losses

    Institute of Scientific and Technical Information of China (English)

    岳玉波; 沙之敏; 赵峥; 陆欣欣; 张金秀; 赵琦; 曹林奎

    2014-01-01

    The loss of nitrogen and phosphorus due to excessive fertilizer application has become a major form in agricultural non-point pollution. In order to explore the impact of different planting patterns (conventional cultivation, green rice-frog ecosystem, organic rice-frog ecosystem) on nitrogen and phosphorus loss, a field experiment was conducted and the characteristics of nitrogen and phosphorus in surface water, runoff, leakage as well as rice yield differences analyzed in three paddy ecosystems. The results showed that among the paddy ecosystems, the order of average concentration of total nitrogen (TN) in surface water was:conventional cultivation (18.87 mg·L−1) > green rice-frog ecosystem (8.98 mg·L−1) > organic rice-frog ecosystem (8.20 mg·L−1). Compared with conventional cultivation, green rice-frog ecosystem and organic rice-frog ecosystem decreased TN loss during rice growth season by 15.27% and 25.76%, respectively. The TN runoff loss was in the following order: green rice-frog ecosystem >conventional cultivation>organic rice-frog ecosystem. NH4+-N was the main form of TN runoff. The order of TN leaching loss of was conventional cultivation > green rice-frog ecosystem > organic rice-frog ecosystem, with NO3−-N as the main form of TN leaching. Also the ratio of total TN loss to nitrogen fertilizer use in the three treatments was in the range of 1.25%ԟ2.38%, all less than 3%. Average total phosphorus (TP) concentration of surface water was in the following order:organic rice-frog ecosystem (0.82 mg·L−1)>green rice-frog ecosystem (0.64 mg·L−1)>conventional cultivation (0.37 mg·L−1). Total loss of TP was in the order of:organic rice-frog ecosystem > green rice-frog ecosystem > conventional cultivation. Then the order of proportion of total loss of phosphorous fertilizer was:green rice-frog ecosystem>conventionally cultivation treatment>organic rice-frog ecosystem, most of which was dissolved phosphorus. The order of rice yield under the

  11. High-yielding Cultivation Technology for Middle Rice- succeeded Black Fungus%中稻—袋料黑木耳高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    吴火金

    2015-01-01

    为充分利用土地闲置田的空间,种植一季水稻后,再放置黑木耳,既发挥土地资源,又提高经济效益,从而增加农民收入.主要阐述了浦城县种植一季中稻后袋料黑木耳的主要高产栽培技术,病虫发生与防治.%In this paper, to make full use of idle land field space, after the rice planting season, again to place black fungus, both play land resources, and improve the economic benefit, increasing farmers' income. In this paper, we mainly expounds middle rice planting season succeeded after black fungus main high-yield culti-vation techniques, the occurrence and prevention of diseases and pests.

  12. 天优华占在建阳市作烟后稻种植表现及栽培技术%Planting Performance and Cultivation Techniques of Hybrid Rice Combination Tianyouhuazhan as Post-tobacco Rice at Jianyang City

    Institute of Scientific and Technical Information of China (English)

    罗祠平

    2014-01-01

    天优华占是由中国水稻研究所、中国科学院与发育生物研究所和广东省农业科学院水稻研究所利用天丰A×华占选育而成的籼型三系交杂水稻新品种,于2008年通过国家农作物品种审定。介绍了2011-2012年天优华占在建阳市作烟后稻种植表现及栽培技术。%A new hybrid rice combination, Tianyouhuazhan, was developed from the cross of a CMS line Tianfeng A and a restorer line Huazhan by China National Rice Research Institute, Institute of Developmental Biology of Chinese Academy of Sciences, and Rice Institute of Guangdong Academy of Agricultural Sciences. It was released by nation in 2008. This paper introduced its planting performance and cultivation techniques planted as post-tobacco rice at Jianyang city in 2011-2012.

  13. The Source of Genes Related to Rice Grain Starch Synthesis Among Cultivated Varieties and Its Contribution to Quality

    Institute of Scientific and Technical Information of China (English)

    YAN Chang-jie; TIAN Shun; ZHANG Zheng-qiu; HAN Yue-peng; CHEN Feng; LI Xin; GU Ming-hong

    2007-01-01

    The property of starch in rice grain endosperm is a very important determinant for rice quality, and it is essential to understand the genetic effect of the genes related to starch synthesis in high-yielding rice varieties for rice quality improvement. The physicochemical properties (e.g., amylose content, gel consistency, and RVA profile) were assessed on 53 rice varieties, including certain typical indica/japonica landraces and certain high-yielding modern varieties. And molecular markers for Sbel, Sbe3 developed on the basis of sequence diversities between the rice subspecies indica and japonica, together with PCR-Acc Ⅰ marker for Wx gene were used to investigate the genotypes of 53 rice cultivars. The result showed that the developed molecular markers for Wx, Sbel, Sbe3 could distinguish indica or japonica alleles at three loci. Among all the 53 rice cultivars, six genotypes were observed when Sbel, Sbe3, and Wx loci were considered together, while the genotypes of WxiSbeljSbe3i and WxiSbeljSbe3j were absent. In order to explore the genetic effects of the three genes, especially for starch branching enzyme genes, ANOVA and multiple comparison analysis were conducted.The results showed that rice cultivars with different genotypes exhibited different phenotypes, including amylose content,gel consistency and certain RVA characteristics, and the significant differences among the six genotypes were observed.It was concluded that these three genes had randomly recombined during the process of the rice variety development.And the genetic effects of indica and japonica alleles at three gene loci were different, of which, Wx gene plays a major role in determining the starch properties, followed by Sbel and Sbe3, and the genetic effects of Sbel and Sbe3 in different backgrounds (Wxi, Wxj) are different. The results have provided a clue for rice good quality variety development, and the molecular markers will benefit to the improvement in quality of rice.

  14. Effects of N loading rate on CH4 and N2O emissions during cultivation and fallow periods from forage rice fields fertilized with liquid cattle waste.

    Science.gov (United States)

    Riya, S; Zhou, S; Kobara, Y; Sagehashi, M; Terada, A; Hosomi, M

    2015-09-15

    The use of liquid cattle waste (LCW) as a fertilizer for forage rice is important for material recycling because it can promote biomass production, and reduce the use of chemical fertilizer. Meanwhile, increase in emission of greenhouse gases (GHGs), especially CH4 and N2O would be concerned. We conducted a field study to determine the optimum loading rate of LCW as N to promote forage rice growth with lower GHG emissions. The LCW was applied to forage rice fields, N100, N250, N500, and N750, at four different N loading rates of 107, 258, 522, and 786 kg N ha(-1), respectively, including 50 kg N ha(-1) of basal chemical fertilizer. The above-ground biomass yields increased 14.6-18.5 t ha(-1) with increases in N loading rates. During the cultivation period, both the CH4 and N2O fluxes increased with increases in LCW loading rates. In the treatments of N100, N250, N500, and N750, the cumulative CH4 emissions during the entire period, including cultivation and fallow period were 29.6, 18.1, 54.4, and 67.5 kg C ha(-1), respectively, whereas those of N2O were -0.15, -0.02, 1.49, and 5.82 kg N ha(-1), respectively. Considering the greenhouse gas emissions and above-ground biomass, the yield-scaled CO2-equivalents (CO2-eqs) were 66.3, 35.9, 161, and 272 kg CO2 t(-1) for N100, N250, N500, and N750, respectively. These results suggest that N250 is the most appropriate LCW loading rate for promoting forage rice production with lower GHG emissions. PMID:26164270

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

    Science.gov (United States)

    Jayawickreme, D.

    2015-12-01

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

  16. LABA1, a Domestication Gene Associated with Long, Barbed Awns in Wild Rice.

    Science.gov (United States)

    Hua, Lei; Wang, Diane R; Tan, Lubin; Fu, Yongcai; Liu, Fengxia; Xiao, Langtao; Zhu, Zuofeng; Fu, Qiang; Sun, Xianyou; Gu, Ping; Cai, Hongwei; McCouch, Susan R; Sun, Chuanqing

    2015-07-01

    Common wild rice (Oryza rufipogon), the wild relative of Asian cultivated rice (Oryza sativa), flaunts long, barbed awns, which are necessary for efficient propagation and dissemination of seeds. By contrast, O. sativa cultivars have been selected to be awnless or to harbor short, barbless awns, which facilitate seed processing and storage. The transition from long, barbed awns to short, barbless awns was a crucial event in rice domestication. Here, we show that the presence of long, barbed awns in wild rice is controlled by a major gene on chromosome 4, LONG AND BARBED AWN1 (LABA1), which encodes a cytokinin-activating enzyme. A frame-shift deletion in LABA1 of cultivated rice reduces the cytokinin concentration in awn primordia, disrupting barb formation and awn elongation. Sequencing analysis demonstrated low nucleotide diversity and a selective sweep encompassing an ∼800-kb region around the derived laba1 allele in cultivated rice. Haplotype analysis revealed that the laba1 allele originated in the japonica subspecies and moved into the indica gene pool via introgression, suggesting that humans selected for this locus in early rice domestication. Identification of LABA1 provides new insights into rice domestication and also sheds light on the molecular mechanism underlying awn development.

  17. Coupling of Belowground Carbon Cycling and Stoichiometry from Organisms to Ecosystems along a Soil C Gradient Under Rice Cultivation

    Science.gov (United States)

    Hartman, W.; Ye, R.; Horwath, W. R.; Tringe, S. G.

    2015-12-01

    Ecological stoichiometry is a framework linking biogeochemical cycles to organism functional traits that has been widely applied in aquatic ecosystems, animals and plants, but is poorly explored in soil microbes. We evaluated relationships among soil stoichiometry, carbon (C) cycling, and microbial community structure and function along a soil gradient spanning ~5-25% C in cultivated rice fields with experimental nitrogen (N) amendments. We found rates of soil C turnover were associated with nutrient stoichiometry and phosphorus (P) availability at ecosystem, community, and organism scales. At the ecosystem scale, soil C turnover was highest in mineral soils with lower C content and N:P ratios, and was positively correlated with soil inorganic P. Effects of N fertilization on soil C cycling also appeared to be mediated by soil P availability, while microbial community composition (by 16S rRNA sequencing) was not altered by N addition. Microbial communities varied along the soil C gradient, corresponding with highly covariant soil %C, N:P ratios, C quality, and carbon turnover. In contrast, we observed unambiguous shifts in microbial community function, imputed from taxonomy and directly assessed by shotgun sequenced metagenomes. The abundance of genes for carbohydrate utilization decreased with increasing soil C (and declining C turnover), while genes for aromatic C uptake, N fixation and P scavenging increased along with potential incorporation of C into biomass pools. Ecosystem and community-scale associations between C and nutrient substrate availability were also reflected in patterns of resource allocation among individual genomes (imputed and assembled). Microbes associated with higher rates of soil C turnover harbored more genes for carbohydrate utilization, fewer genes for obtaining energetically costly forms of C, N and P, more ribosomal RNA gene copies, and potentially lower C use efficiency. We suggest genome clustering by functional gene suites might

  18. Optimization of removal and recycling ratio of cover crop biomass using carbon balance to sustain soil organic carbon stocks in a mono-rice paddy system

    NARCIS (Netherlands)

    Haque, Md. Mozammel; Kim, Sang Yun; Kim, Gil Won; Kim, Pil Joo

    2015-01-01

    The cultivation of a winter cover crop as green manure is strongly recommended to improve soil quality in mono-rice paddy systems; however, the biomass is largely removed to feed cattle in many Asian regions. To determine the minimum recycling ratio of the biomass that can sustain soil organic carbo

  19. Rice Cultivation Methods and Their Sustainability Aspects: Organic and Conventional Rice Production in Industrialized Tropical Monsoon Asia with a Dual Cropping System

    Directory of Open Access Journals (Sweden)

    Hung-Chun Lin

    2016-06-01

    Full Text Available Options to tackle the sustainability challenges faced in the production of rice, including global and local environmental perspectives, need to be discussed. Here, the global warming potential, water consumption and cumulative energy demand were analyzed using a life-cycle assessment to highlight the sustainability aspects of rice production in Taiwan, where a mixed organic and conventional rice production with a dual cropping system is practiced. The results show that the conventional farming method practiced in Houbi district contributes less to global warming and annual water consumption and consumes less energy than the organic method practiced in Luoshan village on a grain weight basis. It is also more lucrative for farmers because of the higher rice yield. Considering the yield ratio based on the data from two districts, the regional characteristics are more responsible for these differences. Giving up dual cropping to avail water to other sectors by fallowing during the second cropping season is preferable from the GHG emission and productivity perspectives. However, because water shortages usually occur in the first cropping season, it is more realistic to fallow during the first cropping season when domestic and other industrial users have the higher priority. The results presented here can serve as the foundation for exploring the possibilities of options, such as new biorefinery technologies and water allocation policies, in relation to influences on GHG emissions and the national self-sufficiency of rice.

  20. 黑龙江垦区寒地水稻“三化一管”模式化栽培标准化生产推广应用%Standardized Cultivation of Cold Region Rice in Heilong jiang Reclamation Area

    Institute of Scientific and Technical Information of China (English)

    马德全; 霍立君; 李玉成

    2014-01-01

    The paper analyzes the characteristics of rice production in Heilongjiang Reclamation Area (HRA) and the achievements made through innovative research and practice, evaluates the standardized mode of rice cultivation and technical standards for rice production, which play a key role in guaranteeing the growth of grain total output in Heilongjiang reclamation area and make great contributions to the national grain safety.

  1. Application and Discussion of Factory Darkening Seedlings Cultivation Technology for Rice Combination%水稻工厂化暗化育秧技术应用探讨

    Institute of Scientific and Technical Information of China (English)

    刘清亮

    2015-01-01

    当前水稻育秧技术是机械插秧的重要配套,是机械化插秧的技术保障和支撑,是农艺和农机的有机结合.育秧技术的好坏,是机械化插秧技术成功与否的关键环节.通过这几年生产实践,总结水稻工厂化暗化育秧关键技术,为大面积推广水稻工厂化育秧提供参考.%In currently, rice seedlings technology is one of the important supporting mechanical transplanting, is the technical guarantee and supporting mechanization planting, and is the combination of agronomy and farm machinery. What,s more, the cultivation technology is the key to the success of mechanization planting technology. Through recent year research, we summarizes the rice factory darkening boards for key technologies, provide reference for large extension rice seedlings.

  2. Rice seeding-raising techniques by factorized cultivation for machinery transplanting%水稻工厂化机插育秧技术

    Institute of Scientific and Technical Information of China (English)

    陈惠宗

    2015-01-01

    水稻工厂化机插育秧技术是利用机械化生产线精量播种,采用温室和大棚控制水、肥、土、温、湿、气等条件的一种规模化育秧方式。该文着重从水稻品种搭配、利用相关配套设备进行催芽、营养土的配制、流水线播种作业及秧苗管理等方面总结了水稻工厂化机插育秧技术。%Rice seeding-raising techniques by factorized cultivation for machinery transplanting is a scale seedling-raising method which using mechanized production line of precise sowing,and controlling water,fertilizer,soil,temperature,hu-midity,air and other conditions in greenhouse and plastic house,. This paper summarized the rice seeding-raising tech-niques,including rice variety collocation,using relevant corollary equipment for stimulating germination,nutritive soil prepa-ration,pipeline sowing operation and seedling management.

  3. Rice Varieties in Archaic East Asia: Reduction of Its Diversity from Past to Present Times.

    Science.gov (United States)

    Kumagai, Masahiko; Kanehara, Masaaki; Shoda, Shin'ya; Fujita, Saburo; Onuki, Shizuo; Ueda, Shintaroh; Wang, Li

    2016-10-01

    The Asian cultivated rice, Oryza sativa, is one of the most important crops feeding more than a third of global population. In spite of the studies for several decades, the origin and domestication history of rice varietal groups, japonica and indica, have not been fully unveiled. Genetic information of ancient rice remains is essential for direct and exclusive insight into the domestication history of rice. We performed ancient DNA analysis of 950- to 2,800-year-old rice remains excavated from Japan and Korea. We found the presence of both japonica- and indica-type varieties in the Yayoi period and the middle ages of Japan and the middle part of Korea Peninsula 2,000 years ago. It is popularly considered that japonica has been exclusively cultivated in northern part of East Asia including Japan and Korea. Our result disclosed unexpectedly wide diversity of rice varieties in archaic East Asia. The present results from ancient rice DNA reveal an exclusive insight for the domestication history of rice which is not provided as far as contemporary rice. PMID:27461246

  4. Towards higher nitrogen efficiency in European rice cultivation. A case study for the Camargue, South of France.

    OpenAIRE

    Stutterheim, N.C.

    1995-01-01

    This study focuses on an increase in the efficiency of fertilizer nitrogen in irrigated, direct seeded rice. Three indicators for efficiency were used: agronomic efficiency, utilization efficiency and recovery. Experiments were conducted in the Camargue in the South of France, to quantify these indicators for standard non-coated prilled urea under conventional management of irrigated rice. The results were compared to those derived from data originating from other surveys within the Mediterra...

  5. Evaluation of Nitrogen and Potassium Uptake and Efficiency of Two Rice Varieties Cultivated on an Acid Soil

    Directory of Open Access Journals (Sweden)

    Shajarutulwardah M. Yusob

    2007-01-01

    Full Text Available A pot study was carried with the following objectives: (i To investigate N and K uptake of MR 220 and ARC 2 rice varieties grown on Bekenu series (Tipik Tualemkuts, and (ii To investigate N and K use efficiency of MR 220 and ARC 2 grown on Bekenu series. Treatments evaluated were: (i MR 220 and ARC 2 under fertilized condition (T1, and (ii MR 220 and ARC 2 under unfertilized condition (T0. The experiment was conducted in a glasshouse at Universiti Putra Malaysia Bintulu Campus, Sarawak, Malaysia. Altogether 24 pots were used having a completely randomized design (CRD with 6 replications (for each treatment and each variety. Nitrogen and K were applied in the forms of urea (46 % N and muriate of potash (60 % K2O for the two varieties. For T1 of MR 220, N, K, and P were applied at the rates of 4.0 g N, 1.10 g K2O and 2.13 g P2O5 per pot, respectively in split. In the case of T1 of ARC 2, N, K, and P rates used were 1.30 g N, 0.8 g K2O, and 1.70 g P2O5 per pot, respectively in split. At 65 days (ARC 2 and 70 days (MR 220 after planting, plants were sampled and partitioned into roots and stem, and their dry weight, N, and K concentrations determined using standard procedures. Soil sampling was done before and after fertilization. Soil total N was determined using the Kjeldahl method while exchangeable K, Ca, Mg, and Na were extracted by the double acid method and their concentrations determined by atomic absorption spectrophotometry. The dry ashing method was used for the determination of K, Ca, Mg and Na concentrations in plant tissues while the Kjeldahl method was used to determine total N in plant tissues. The concentrations multiplied by the oven dried weight of roots and stem provided N, K, Ca, Mg and Na uptake in these plant parts. The N and K use efficiency was then calculated using the subtraction method. With the exception of Ca, urea and KCl application significantly increased soil N, K, Mg, and Na concentrations. Application of K

  6. Mechanisms of production and emission of methane in rice fields. Impact of fertilization and cultivated species; Mechanismen der Produktion und Emission von Methan in Reisfeldern. Abhaengigkeit von Feldduengung und angebauter Varietaet

    Energy Technology Data Exchange (ETDEWEB)

    Butterbach-Bahl, K.

    1993-12-31

    Methane emissions from rice fields are a significant source (approx. 20%) of atmospheric methane. Laboratory tests and field tests have shown that throughout the entire vegetation period, more than 80% of the total methane emissions from rice fields in Italy were released by the aerating tissue of the rice plant. The amount of methane emissions has been found to depend on the rice species cultivated, and on fertilization. Additional studies into the gas transport capability of the aerenchyma of the rice plants show a clear correlation between highest diffusion resistance of the aerenchyma of a given rice plant, and lowest methane emissions measured in the rice species. This is a result that opens up new possibilities of reducing methane emissions from rice fields. (orig.) [Deutsch] Methan-Emissionen aus Reisfeldern sind eine signifikante Quelle (ca. 20%) fuer atmosphaerisches Methan. In Labor- und Freilandexperimenten konnte nachgewiesen werden, dass waehrend der Vegetationsperiode ueber 80% der Gesamt-Methan-Emissionen aus italienischen Reisfeldern ueber das Aerenchymsystem der Reispflanze erfolgt. Die Hoehe der Methan-Emission war von der angebauten Reisvarietaet und der Feldduengung abhaengig. Ergaenzende Untersuchungen zur Gaswegigkeit des Aerenchymsystems der Reispflanze zeigten, dass die Reisvarietaet mit den groessten Diffusionswiderstaenden des Aerenchymsystems auch die niedrigsten Methan-Emissionsraten aufwies. Dieses Ergebnis eroeffnet neue Moeglichkeiten zur Reduktion der Methan-Emissionen aus Reisfeldern. (orig.)

  7. Effects of Different Cultivation Modes on Yield and Nitrogen Absorption of Double Cropping Super Rice%不同栽培模式对双季超级稻产量及氮素吸收的影响

    Institute of Scientific and Technical Information of China (English)

    林洪鑫; 黄大山; 熊多根; 程飞虎; 袁展汽; 曹开蔚; 黄雪花

    2012-01-01

    以超级早稻春光1号和超级晚稻淦鑫688为材料,采用抛秧方式,研究了不同栽培模式对其产量及氮素吸收的影响.结果表明,早晚稻的产量均以三高一保栽培模式和精确定量栽培模式>三控栽培模式>常规栽培模式.三高一保栽培模式的有效穗数、成穗率、结实率和千粒重均较高,而精确定量栽培模式的有效穗数最高,但成穗率较低.与常规栽培模式相比,精确定量模式、三高一保模式和三控栽培模式可提高双季超级稻的生物产量、氮素积累总量和氮素利用率.三高一保栽培模式明显降低了生产100 kg籽粒的需氮量.%Using super early rice variety Chunguang No. 1 and super late rice variety Ganxin 688 as experimental materials, the author studied the effects of different cultivation modes on the yield and nitrogen absorption of rice, which was transplanted by seedling - throwing mode. The results showed that the yield of both early rice and late rice cultivated by different modes had the following order : precise and quantitative cultivation mode ( PQCM) and three - high and one - guarantee cultivation mode ( THOGCM) > three -control cultivation mode ( TCCM ) > conventional cultivation mode ( CCM) . The number of effective spike, ear - bearing percentage, setting rate and 1000 - grain weight of rice in treatment THOGCM were higher. The effective spike number of rice in treatment PQCM was maximum, but its ear - bearing percentage was lower. In comparison with CCM, the PQCM, THOGCM and TCCM could enhance the biomass, total nitrogen accumulation and nitrogen utilization rate of double cropping super rice, and THOGCM obviously reduced the nitrogen requirement for 100 kg grain production.

  8. Cultivation Technology for Rice Mechanical Transplanting%水稻机插露天简易操作育秧技术

    Institute of Scientific and Technical Information of China (English)

    连孝忠

    2014-01-01

    水稻机插简易操作育秧技术是一项操作简单,农民容易接受的一种育秧技术。2012-2014年浦城县引进机插秧简易操作育秧技术,效果很好,可节约成本480元/667m2。介绍了浦城县水稻机插露天简易操作育秧技术。%Rice machine simple operating seedlings technique was a simple operation, farmers easier to accept a base technology. The machine simple operating seedlings planting technology was introduced in Pucheng county of Fujian province during the year of 2010-2012, which showed than the effect was very good, save cost 480 yuan/667m2. In this paper, we introduced simple operating seedlings cultivation technology in Pucheng country.

  9. Efficient Cultivation Techniques of Red Scented Rice and Strawberry%南方红香稻-草莓高效栽培技术

    Institute of Scientific and Technical Information of China (English)

    覃慧玲

    2014-01-01

    The cultivation mode of south red scented rice and strawberry was introduced,which including sowing date arrangement,sowing date variety selection,moisture and fertilization management,prevention and control of diseases and pests,and timely harvest,as a reference to guide the planting structure adjustment,which had the vital significance for promoting farmers’fruit grain plumpness’.%介绍南方红香稻要草莓粮经高效栽培模式,包括播期安排、良种选择、水肥运筹、病虫防控与适时收获等,对指导种植业结构调整,带动农民“粮果双增”具有重要的意义。

  10. Comparison of pooled standard deviation and standardized-t bootstrap methods for estimating uncertainty about average methane emission from rice cultivation

    Science.gov (United States)

    Kang, Namgoo; Jung, Min-Ho; Jeong, Hyun-Cheol; Lee, Yung-Seop

    2015-06-01

    The general sample standard deviation and the Monte-Carlo methods as an estimate of confidence interval is frequently being used for estimates of uncertainties with regard to greenhouse gas emission, based on the critical assumption that a given data set follows a normal (Gaussian) or statistically known probability distribution. However, uncertainty estimated using those methods are severely limited in practical applications where it is challenging to assume the probability distribution of a data set or where the real data distribution form appears to deviate significantly from statistically known probability distribution models. In order to solve these issues encountered especially in reasonable estimation of uncertainty about the average of greenhouse gas emission, we present two statistical methods, the pooled standard deviation method (PSDM) and the standardized-t bootstrap method (STBM) based upon statistical theories. We also report interesting results of the uncertainties about the average of a data set of methane (CH4) emission from rice cultivation under the four different irrigation conditions in Korea, measured by gas sampling and subsequent gas analysis. Results from the applications of the PSDM and the STBM to these rice cultivation methane emission data sets clearly demonstrate that the uncertainties estimated by the PSDM were significantly smaller than those by the STBM. We found that the PSDM needs to be adopted in many cases where a data probability distribution form appears to follow an assumed normal distribution with both spatial and temporal variations taken into account. However, the STBM is a more appropriate method widely applicable to practical situations where it is realistically impossible with the given data set to reasonably assume or determine a probability distribution model with a data set showing evidence of fairly asymmetric distribution but severely deviating from known probability distribution models.

  11. Towards higher nitrogen efficiency in European rice cultivation. A case study for the Camargue, South of France.

    NARCIS (Netherlands)

    Stutterheim, N.C.

    1995-01-01

    This study focuses on an increase in the efficiency of fertilizer nitrogen in irrigated, direct seeded rice. Three indicators for efficiency were used: agronomic efficiency, utilization efficiency and recovery. Experiments were conducted in the Camargue in the South of France, to quantify these indi

  12. Between Archaeology and Text: The Origins of Rice Consumption and Cultivation in the Middle East and the Mediterranean

    Directory of Open Access Journals (Sweden)

    Sureshkumar Muthukumaran

    2014-09-01

    Full Text Available Asiatic Rice 'Oryza sativa' L. (Poaceae is a domesticated grain crop native to the tropical and subtropical regions of Asia, which presently ranks among the most important grains in a global diet. 'Oryza sativa' is comprised of two distinct phylogenetic subspecies, namely 'japonica' and 'indica', for which genetic evidence indicates at least two centres of domestication: the Lower Yangtze valley for the broad thick-grained japonica (c. 4000 BC and the Gangetic basin for the thin elongated indica variety (c. 2500 BC (Fuller et al 2010; idem 2011; Nesbitt et al 2010: 325–7. Modern genetics of landraces from northeast India may indicate a third distinct origin for the so-called 'aus' rice varieties (Londo et al 2006: 9581–2. The genetic history of this taxon is further complicated by post-domestication hybridisation between domesticates and their wild ancestors as well as the presence of rarer forms like the aromatic rice varieties ('basmati' in South Asia and 'sadri' from Iran which may be of independent origin (Nesbitt et al 2010: 324–5. In South Asia domesticated rice is attested at various archaeological sites in the Ganges basin from the mid-3rd millennium BC onwards. It subsequently appears at mature and late Harappan levels in north-western India (c. 2000 BC before arriving at the edge of the eastern Iranian plateau at Pirak on the north Kachi plain in the early 2nd millennium BC (Costantini 1981; Fuller 2006: 36; Sato 2005. The presence of rice at Pirak heralds its gradual westward movement along the Iranian plateau via overland and perhaps even coastal routes into western Iran and Mesopotamia.

  13. Levels of dioxins in rice, wheat, soybean, and adzuki bean cultivated in 1999 to 2002 in Japan and estimation of their intake.

    Science.gov (United States)

    Otani, Takashi; Seike, Nobuyasu; Miwa, Tetsuhisa

    2006-08-01

    A total of 369 samples of rice (n = 311), wheat (n = 10), soybean (n = 44), and adzuki bean (n = 4) collected from various locations in Japan between 1999 and 2002 were analyzed for PCDDs, PCDFs (PCDD/Fs) and coplanar PCBs. Sampling points within about 1 km of operational municipal waste incinerators that were considered sources of dioxins were defined as "near-source" areas, and all other sampling points were defined as "general" areas. The toxic equivalent quantity (TEQ) values of soybean samples collected from near-source areas were significantly higher (p pollution. The TEQs of the crops varied widely, but the median value of each crop was quite low, at 0.000021, 0.00013, 0.0000095, and 0.00016 pg-TEQ/g wet wt. in rice, wheat, soybean and adzuki bean, respectively. On the basis of these survey results, the daily intake of PCDD/Fs and coplanar PCBs from rice, wheat, soybean, and adzuki bean was calculated. The daily intakes from these crops were estimated to be 0.0056 pg-TEQ/kg B.W./day on the assumption that "not detected" (ND) could be taken as zero, ND = 0, and 0.18 pg-TEQ/kg B.W./day if ND is put equal to 1/2 LOD (half the limit of detection). In comparison with the tolerable daily intake set in Japan for PCDD/Fs and coplanar PCBs (4 pg-TEQ/kg B.W./day), it was considered that the levels of contamination by PCDD/Fs and coplanar PCBs in these crops cultivated in the environment of Japan do not present a problem.

  14. The use of 32P Method to Evaluate the Growth of Lowland Rice Cultivated in a System of Rice Intensification (SRI

    Directory of Open Access Journals (Sweden)

    A. Citraresmini

    2013-08-01

    Full Text Available A pot experiment has been conducted to evaluate the growth of the Dyah Suci, a lowland rice variety, in an SRI (System of Rice Intensification planting system. The phosphorus-32 (32P isotope technique was used to evaluate the growth of plants in relation with their phosphorus uptake. The uptake was assumed to vary in the same direction as the growth of the plant. The 32P uptake is assumed to vary in the opposite direction to the plant’s total phosphorus uptake. Here the 32P uptake is expressed in count per minutes (cpm which is then transformed to disintegration per minute (dpm. The results show that, in terms of promoting the plant’s uptake of phosphorus, the SRI planting system is superior to the conventional planting system, and it is manifested in the higher dry weight of straw and grain. From this experiment it is concluded that the 32P method can be used satisfactorily as a tool for explaining the relation between P-uptake and plant growth

  15. Assessing impacts of alternative fertilizer management practices on both nitrogen loading and greenhouse gas emissions in rice cultivation

    Science.gov (United States)

    Zhao, Zheng; Yue, Yubo; Sha, Zhimin; Li, Changsheng; Deng, Jia; Zhang, Hanlin; Gao, Maofang; Cao, Linkui

    2015-10-01

    Nitrogen (N) losses and greenhouse gas (GHG) emissions from paddy rice fields contaminate water bodies and atmospheric environment. A 2-year (2012-2013) field experiment was conducted at a typical paddy rice field in a rural suburb of Shanghai, China. N losses and GHG emissions from the paddy field with alternative fertilizer management practices were simultaneously measured. Four treatments were tested in the experiment: applications of only chemical synthetic fertilizer urea (CT), only organic manure (OT), a combination of the two types of fertilizers (MT) and a control (CK). Results from the field study indicated that CT produced the highest seasonal N loading rate (18.79 kg N/ha) and N2O emissions (1.81 kg N2O/ha) but with the lowest seasonal CH4 emissions (69.09 kg CH4/ha). With organic manure applied, MT and OT respectively reduced N loading by 21.86% and 30.41%, reduced N2O emissions by 28.34% and 69.41%, but increased CH4 emissions by 137% and 310% in comparison with CT. However, the net impact of CH4 and N2O emissions on global warming was enhanced when organic manure was applied. In addition, CT and MT produced the optimal rice yield during the experimental period, while OT treatment led to a yield reduction by 9.29% compared with CT. In conclusion, the impacts of alternative fertilizer management practices on ecosystem services ought to be assessed specifically due to the great variations across rice yields, N loss and GHG emissions.

  16. Rice Root Architectural Plasticity Traits and Genetic Regions for Adaptability to Variable Cultivation and Stress Conditions1[OPEN

    Science.gov (United States)

    Sandhu, Nitika; Raman, K. Anitha; Torres, Rolando O.; Audebert, Alain; Dardou, Audrey; Kumar, Arvind; Henry, Amelia

    2016-01-01

    Future rice (Oryza sativa) crops will likely experience a range of growth conditions, and root architectural plasticity will be an important characteristic to confer adaptability across variable environments. In this study, the relationship between root architectural plasticity and adaptability (i.e. yield stability) was evaluated in two traditional × improved rice populations (Aus 276 × MTU1010 and Kali Aus × MTU1010). Forty contrasting genotypes were grown in direct-seeded upland and transplanted lowland conditions with drought and drought + rewatered stress treatments in lysimeter and field studies and a low-phosphorus stress treatment in a Rhizoscope study. Relationships among root architectural plasticity for root dry weight, root length density, and percentage lateral roots with yield stability were identified. Selected genotypes that showed high yield stability also showed a high degree of root plasticity in response to both drought and low phosphorus. The two populations varied in the soil depth effect on root architectural plasticity traits, none of which resulted in reduced grain yield. Root architectural plasticity traits were related to 13 (Aus 276 population) and 21 (Kali Aus population) genetic loci, which were contributed by both the traditional donor parents and MTU1010. Three genomic loci were identified as hot spots with multiple root architectural plasticity traits in both populations, and one locus for both root architectural plasticity and grain yield was detected. These results suggest an important role of root architectural plasticity across future rice crop conditions and provide a starting point for marker-assisted selection for plasticity. PMID:27342311

  17. The World of Rice

    Institute of Scientific and Technical Information of China (English)

    VALERIE SARTOR

    2010-01-01

    @@ Pilafs, risottos, soups, snacks, paellas,stuffing, vinegars, wines and desserts-rice is used all over the world in myriad ways as food and drink.Although rice is one of the world's most ancient foods and it is impossible to know exactly where and when cultivation of this marvelous grain began, China is popularly acknowledged as the homeland of rice. Chinese people have many legends about rice. Some describe a benevolent goddess in silk robes whose gown accidentally picked up stray rice grains, which she dropped from the heavens to humans below. It's also said that Shennong, the Divine Farmer in Chinese myth, sowed the first rice on earth.

  18. The ADH1B Arg47His polymorphism in East Asian populations and expansion of rice domestication in history

    Directory of Open Access Journals (Sweden)

    Zhong Hua

    2010-01-01

    Full Text Available Abstract Background The emergence of agriculture about 10,000 years ago marks a dramatic change in human evolutionary history. The diet shift in agriculture societies might have a great impact on the genetic makeup of Neolithic human populations. The regionally restricted enrichment of the class I alcohol dehydrogenase sequence polymorphism (ADH1BArg47His in southern China and the adjacent areas suggests Darwinian positive selection on this genetic locus during Neolithic time though the driving force is yet to be disclosed. Results We studied a total of 38 populations (2,275 individuals including Han Chinese, Tibetan and other ethnic populations across China. The geographic distribution of the ADH1B*47His allele in these populations indicates a clear east-to-west cline, and it is dominant in south-eastern populations but rare in Tibetan populations. The molecular dating suggests that the emergence of the ADH1B*47His allele occurred about 10,000~7,000 years ago. Conclusion We present genetic evidence of selection on the ADH1BArg47His polymorphism caused by the emergence and expansion of rice domestication in East Asia. The geographic distribution of the ADH1B*47His allele in East Asia is consistent with the unearthed culture relic sites of rice domestication in China. The estimated origin time of ADH1B*47His allele in those populations coincides with the time of origin and expansion of Neolithic agriculture in southern China.

  19. Hybrid sterility in plant: stories from rice.

    Science.gov (United States)

    Ouyang, Yidan; Liu, Yao-Guang; Zhang, Qifa

    2010-04-01

    Hybrid sterility is the most common form of postzygotic reproductive isolation in plants. The best-known example is perhaps the hybrid sterility between indica and japonica subspecies of Asian cultivated rice (Oryza sativa L.). Major progress has been reported recently in rice in identifying and cloning hybrid sterility genes at two loci regulating female and male fertility, respectively. Genetic analyses and molecular characterization of these genes, together with the results from other model organisms especially Drosophila, have advanced the understanding of the processes underlying reproductive isolation and speciation. These findings also have significant implications for crop genetic improvement, by providing the feasibility and strategies for overcoming intersubspecific hybrid sterility thus allowing the development of intersubspecific hybrids.

  20. GENE FLOW BETWEEN RED RICE AND CULTIVATED RICE ESTIMATED BY MICROSATELLITE MARKERS FLUXO GÊNICO ENTRE ARROZ VERMELHO E ARROZ CULTIVADO ESTIMADO POR MEIO DE MARCADORES MICROSSATÉLITES

    Directory of Open Access Journals (Sweden)

    Francisco , Moura Neto

    2007-09-01

    Full Text Available

    The study aimed to evaluate the capacity of SSR markers to detect the gene flow between the red rice (RR and the cultivated rice (CR. SSR is currently used in plant genomic analysis due to the high information content, to be co-dominant, and based on the PCR reaction. The field experiment was organized in ten concentric circles, 5 m to 50 m apart from a central red rice plant, assumed as the pollen donor. One hundred twenty rice CR plants, cv. BR-Irga 409, were planted in the intersections of the concentric circles and the twelve radii. From 51 SSR markers, four were selected due to their capacity to detect the polymorphism between RR and CR, aiming to identify RR alleles in seeds produced by BR-Irga 409 plants. The maximum distance found for gene flow between RR and CR plants was 10 m from the RR plant. In theory, at 0.1% cross pollination rate, this distance can generate 4,710 hybrids between RR and CR. In the next generation, about 3,532 plants would produce exclusively rice grains with red color. The SSR markers were able to identify the gene flow between RR and CR; therefore, they can be useful to increase the precision of cross pollination rate estimates in rice, mainly if used with other methodologies (e.g., herbicide tolerant plants.

    KEY WORDS: Cross pollination; microsatellite markers; Oryza sativa.

    Este trabalho objetivou avaliar a capacidade de marcadores SSR em detectar a ocorrência de fluxo gênico entre o arroz vermelho (AV e o arroz cultivado (AC. Marcadores SSR são utilizados em análise genômica de plantas devido ao alto conteúdo informativo, serem co-dominantes e baseados na reação de PCR. O ensaio de campo foi realizado em dez círculos concêntricos de 5 m a 50 m de distância, a partir de uma planta AV central, que foi a fonte

  1. Field Performance and High-yield Cultivation Technique of Hybrid Rice New Combination Yongyou9%杂交稻新组合“甬优9号”种植表现及高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    林品贵

    2011-01-01

    2009年福鼎市引进甬优9号籼粳交晚稻新品种,连续两年试种表现高产、稳产,稻米品质优;但中感稻瘟病、白叶枯病,易感基腐病、稻曲病、稻飞虱,熟期耐寒性较粳稻弱,较感青枯病。栽培上应注意种子消毒,培育壮秧,大田插足基本苗,加强肥水管理,以及病虫害防治,确保丰产稳产。%Yongyou9,a new later rice cultivar of indica-japoniea hybridization,was introduced to Fuding City in 2009.The results of a two-year trial experiment showed that the rice performed high and stable in yield and good grain quality.However,it was moderately susceptible to rice blast and bacterial blight disease,and susceptible to basal rot,rice false smut and rice planthopper.At maturity stage,it showed weaker in cold tolerance and more susceptible to bacterial wilt than japonica rice.In order to ensure high and stable yield,the cultivation technique of Yongyou9 should pay attention on seed sterilization,fostering strong seedling,transplanting enough basic seedling,strengthening fertilizer and water management and timely insect disease control.

  2. Main Planting Patterns and Their Relevant Cultivation Practices for the Double Rice in Jiangxi Province%江西双季稻主要种植方式及其配套栽培对策

    Institute of Scientific and Technical Information of China (English)

    潘晓华; 李木英; 曾勇军; 程飞虎; 石庆华; 吴建富; 谭雪明; 黄山; 吴自明

    2013-01-01

    就江西双季水稻的发展、种植方式的演变与现状,不同种植方式下的双季水稻产量与效益进行了分析.基于江西双季水稻种植方式多样化的现状,针对手插,抛秧,机插,免耕抛秧,直播和再生稻等不同种植方式,分别提出了适宜不同稻区的双季超级稻品种及高产对策.%This study reviewed the history, evolution, and present situation of planting patterns of the double rice in Jiangxi Province. In addition, the differences in the grain yield and profitability of the double rice under various planting patterns were investigated. Given the diversity of planting patterns of the double rice in Jiangxi Province, to gain a high yield under hand transplanting, throwing, mechanical transplanting, no-tillage throwing, direct seeding, and rationing-rice planting, the authors suggested the selection of super rice cultivars and their relevant cultivation practices suitable for specific planting patterns in different double rice cropping regions of Jiangxi Province.

  3. Characteristic and high-yielding cultivative technique of semilate hybrid rice cultivar Ganyoumingzhan%赣优明占特征特性及其高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    王新珠

    2012-01-01

    该文介绍了赣优明占在武夷山市试种表现及栽培技术,其中栽培技术包括适时播种移栽、合理密植、水肥管理和病虫害防治。%Field performance and cultivation techniques of semilate hybrid rice cultivar Ganyoumingzhan in Wuyishan city were introduced in this paper.The cultivation techniques including timely sowing and transplanting,planting in rational density,fertilizer and water management,insect and disase control.

  4. 五优662水稻种植表现及抛秧高产栽培技术%Planting Performance and High Yield Cultivation Techniques of Wuyou 662 Rice

    Institute of Scientific and Technical Information of China (English)

    胡泽生; 胡桂英; 欧阳美友

    2015-01-01

    Planting performance of Wuyou 662 rice was elaborated,high yield cultivation techniques were summarized from timely planting,cultivating strong seedling,seedling throwing,rational fertilization,scientific water management etc,so as to provide reference.%阐述了五优662水稻的种植表现,并从适时播种、培育壮秧、抛栽、合理施肥、科学管水等方面总结了其高产栽培技术,以供参考。

  5. Survey of Recent Innovations in Aromatic Rice

    OpenAIRE

    Napasintuwong, Orachos

    2012-01-01

    This paper provides situations of aromatic rice demand, and international standards. The history and recent developments of traditional and evolved aromatic rice varieties, namely Basmati rice and Jasmine rice, are reviewed. The emerging aromatic rice innovations from developed countries such as the U.S. and other Asian countries generate a threat to these traditional aromatic rice producers such as India, Pakistan, and Thailand. Under WTO Trade Related Aspects of Intellectual Property Rights...

  6. Identification of Quantitative Trait Loci Affecting Hemicellulose Characteristics Based on Cell Wall Composition in a Wild and Cultivated Rice Species

    Institute of Scientific and Technical Information of China (English)

    Si-Ju Zhang; Xue-Qin Song; Bai-Sheng Yu; Bao-Cai Zhang; Chuan-Qing Sun; J. Paul Knox; Yi-Hua Zhou

    2012-01-01

    Cell wall hemicellulosic polysaccharides are structurally complex and diverse.Knowledge about the synthesisof cell wall hemicelluloses and their biological roles is limited.Quantitative trait loci (QTL) mapping is a helpful tool for the dissection of complex phenotypes for gene identification.In this study,we exploited the natural variation in cell wall monosaccharide levels between a common wild rice,Yuanj,and an elite indica cultivar,Teqing,and performed QTL mapping with their introgression lines (ILs).Chemical analyses conducted on the culms of Yuanj and Teqing showed that the major alterations are found in glucose and xylose levels,which are correlated with specific hemicellulosic polymers.Glycosidic linkage examination revealed that,in Yuanj,an increase in glucose content results from a higher level of mixed linkage β-glucan (MLG),whereas a reduction in xylose content reflects a low level of xylan backbone and a varied arabinoxylan (AX) structure.Seventeen QTLs for monosaccharides have been identified through composition analysis of the culm residues of 95 core ILs.Four major QTLs affecting xylose and glucose levels are responsible for 19 and 21% of the phenotypic variance,respectively.This study provides a unique resource for the genetic dissection of rice cell wall formation and remodeling in the vegetative organs.

  7. Rice Germplasm Resources in China

    Institute of Scientific and Technical Information of China (English)

    YINGCunshan

    1994-01-01

    China is one of the origin countries in Asia of cultiv ated rice (O. sativaL.), and rice is one of the aged-long food crops in the country. The results of the 14C evaluation on the carbonified rice grains unearthed from Hemudu in Yuyao County and Luojiajiao in Tongxiang County of Zhejiang Province indicated that rice in these area has been planted more than 7,000 yrs and indica (hsien) and japonica (keng) rices coexisted with each other.

  8. Asia Rice Crop Estimation and Monitoring (Asia-RiCE) for GEOGLAM

    Science.gov (United States)

    Oyoshi, K.; Tomiyama, N.; Okumura, T.; Sobue, S.

    2013-12-01

    Food security is a critical issue for the international community because of rapid population and economic growth, and climate change. In June 2011, the meeting of G20 agriculture ministers was held to discuss food security and food price volatility, and they agreed on an 'Action Plan on Food Price Volatility and Agriculture'. This plan includes a GEO Global Agricultural Monitoring (GEOGLAM) initiative. The aim of GEOGLAM is to reinforce the international community's ability to produce and disseminate relevant, timely, and accurate forecasts of agricultural production on regional, national, and global scales by utilizing remote sensing technology. GEOGLAM focused on four major grain crops, wheat, maize, soybeans and rice. In particular, Asian countries are responsible for approximately 90% of the world rice production and consumption, rice is the most significant cereal crop in Asian region. Hence, Asian space and agricultural agencies with an interest in the development of rice crop monitoring technology launched an Asia-Rice Crop Estimation & Monitoring (Asia-RiCE) component for the GEOGLAM initiative. In Asian region, rice is mainly cultivated in rainy season, and a large amount of cloud limits rice crop monitoring with optical sensors. But, Synthetic Aperture RADAR (SAR) is all-weather sensor and can observe land surface even if the area is covered by cloud. Therefore, SAR technology would be powerful tool to monitor rice crop in Asian region. Asia-RiCE team required mainly SAR observation data including ALOS-2, RISAT-1, Sentinel-1 and RADARSAT, TerraSAR-X, COSMO-SkyMed for Asia-RiCE GEOGLAM Phase 1 implementation (2013-2015) to the Committee on Earth Observations (CEOS) in the GEOGLAM-CEOS Global Agricultural Monitoring Co-community Meeting held in June 2013. And also, rice crop has complicated cropping systems such as rein-fed or irrigated cultivation, single, double or sometimes triple cropping. In addition, each agricultural field is smaller than that of

  9. Greenhouse Gas Emissions and Global Warming Potential of Traditional and Diversified Tropical Rice Rotation Systems including Impacts of Upland Crop Management Practices i.e. Mulching and Inter-crop Cultivation

    Science.gov (United States)

    Janz, Baldur; Weller, Sebastian; Kraus, David; Wassmann, Reiner; Butterbach-Bahl, Klaus; Kiese, Ralf

    2016-04-01

    Paddy rice cultivation is increasingly challenged by irrigation water scarcity, while at the same time changes in demand (e.g. changes in diets or increasing demand for biofuels) will feed back on agricultural practices. These factors are changing traditional cropping patterns from flooded double-rice systems to the introduction of well-aerated upland crop systems in the dry season. Emissions of methane (CH4) are expected to decrease, while emissions of nitrous oxide (N2O) will increase and soil organic carbon (SOC) stocks will most likely be volatilized in the form of carbon dioxide (CO2). We measured greenhouse gas (GHG) emissions at the International Rice Research Institute (IRRI) in the Philippines to provide a comparative assessment of the global warming potentials (GWP) as well as yield scaled GWPs of different crop rotations and to evaluate mitigation potentials or risks of new management practices i.e. mulching and inter-crop cultivation. New management practices of mulching and intercrop cultivation will also have the potential to change SOC dynamics, thus can play the key role in contributing to the GWP of upland cropping systems. To present, more than three years of continuous measurement data of CH4 and N2O emissions in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) in upland cultivation have been collected. Introduction of upland crops in the dry season reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Moreover, for practices including upland crops, CH4 emissions in the subsequent wet season with paddy rice were reduced by 54-60%. Although annual N2O emissions increased twice- to threefold in the diversified systems, the strong reduction of CH4 led to a significantly lower (pNew upland crop management practices where first implemented during land-preparation for dry season (July) 2015 where i) 6t/ha rice straw was returned to the field and incorporated into

  10. Special rice in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Xianggu Rice: The rice originated from Jiangyong County, Hunan Province. Its characteristics were: even in grain shape, white in color, special fragrant in taste, and sticky in quality. Handongzao: It was from Wannian County, Jiangxi Province. The rice had big, fertile, and white grain, which was soft with fragrant smell, and it had high head rice rate. So, the local peasants liked to plant it. It was one of the "Tribute rice " in old time. Shizhu "Imperial Rice": The rice was also called "Fragrant Rice", was from Siyuan Village, Yuelai Town, Shizhu County, Sichuan Province. It was the treasure among the rices. The grain was bright in color. When it was cooked, the smell was fragrant. It was said that the rice was from "Han Dynasty", and has become the "Tribute Rice " since then. Blood Glutinous Rice: Originated from Changshu City, Jiangsu Province, the rice has been cultivated more than one hundred years. It had high nutrition value. Among the people, the Blood Glutinous Rice was often used as health food for lying-in women and patients. Qufu Fragrant Rice: Its characteristics were: clean, bright, and translucent in grain color, sticky in quality. It was suitable for cooking gruel and was also called "Fragrant Rice" in the local due to its strong fragrance. It was one of the "Tribute Rice" in old time. Taihu Lake Fragrant Japonica: The rice was from the Region of Taihu Lake, Jiangsu Province. The characteristics were: even and big in grain shape, soft in quality, white in color, fragrant in taste. The local people liked to plant and eat it.□ (To be continued) Translated by CHEN Wenhua, From "China Rice",No.1,1994

  11. Relationships of wild and domesticated rices (Oryza AA genome species) based upon whole chloroplast genome sequences.

    Science.gov (United States)

    Wambugu, Peterson W; Brozynska, Marta; Furtado, Agnelo; Waters, Daniel L; Henry, Robert J

    2015-01-01

    Rice is the most important crop in the world, acting as the staple food for over half of the world's population. The evolutionary relationships of cultivated rice and its wild relatives have remained contentious and inconclusive. Here we report on the use of whole chloroplast sequences to elucidate the evolutionary and phylogenetic relationships in the AA genome Oryza species, representing the primary gene pool of rice. This is the first study that has produced a well resolved and strongly supported phylogeny of the AA genome species. The pan tropical distribution of these rice relatives was found to be explained by long distance dispersal within the last million years. The analysis resulted in a clustering pattern that showed strong geographical differentiation. The species were defined in two primary clades with a South American/African clade with two species, O glumaepatula and O longistaminata, distinguished from all other species. The largest clade was comprised of an Australian clade including newly identified taxa and the African and Asian clades. This refined knowledge of the relationships between cultivated rice and the related wild species provides a strong foundation for more targeted use of wild genetic resources in rice improvement and efforts to ensure their conservation. PMID:26355750

  12. Efficient indica and japonica rice identification based on the InDel molecular method: Its implication in rice breeding and evolutionary research

    Institute of Scientific and Technical Information of China (English)

    Bao-Rong Lu; Xingxing Cai; Xin Jin

    2009-01-01

    An efficient molecular method for the accurate and efficient identification of indica and japonica rice was created based on the poly-morphisms of insertion/deletion (InDel) DNA fragments obtained from the basic local alignment search tool (BLAST) to the entire genomic sequences of indica (93-11) and japonica rice (Nipponbare). The 45 InDel loci were validated experimentally by the polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) in 44 typical indica and japonica rice varieties, including 93-11 and Nipponbare. A neutrality test of the data matrix generated from electrophoretic banding patterns of various InDel loci indicated that 34 InDel loci were strongly associated with the differentiation of indica and japonica rice. More extensive analyses involving cultivated rice varieties from 11 Asian countries, and 12 wild Oryza species with various origins confirmed that indica and japonica characteristics could accurately be determined via calculating the average frequency of indica- or japonica-specific alleles on different InDel loci across the rice genome. This method was named as the "InDel molecular index" that combines molecular and statistical methods in determining the indica and japonica characteristics of rice varieties. Compared with the traditional methods based essentially on morphology, the InDel molecular index provides a very accurate, rapid, simple, and efficient method for identifying indica and japonica rice. In addition, the InDel index can be used to determine indica or japonica characteristics of wild Oryza species, which largely extends the utility of this method. The InDel molecular index provides a new tool for the effective selection of appropriate indica or japonica rice germplasm in rice breeding. It also offers a novel model for the study of the origin, evolution, and genetic differentiation of indica and japonica rice adapted to various environmental changes.

  13. Rice-growing Climate Ecology and High-yield Cultivation Techniques of the Basin Surrounding Wuyi Mountain%武夷山盆地稻作气候生态与高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    吴少宏; 赵雅静; 吴华琴; 温桂芳; 周萌

    2011-01-01

    The climate of the basin surrounding Wuyi mountain scenic area is the subtropical climate. Period of safety growth of rice is 235d and the accumulated temperature is 5368 ~C , so it can be double crops in a year. The quantity of heat for planting high-yield late-maturing hybrid rice varieties showed more than single crop but less than two crops. Timely early sowing can modulate the flower filling period of single cropping rice and the first crop of ratoon rice to match high value period of light and temperature in July and August, make the second crop to avoid chilling damage of early autumn. This is a key countermeasure for increasing rice production and income. Corresponding high-yielding cultivation techniques of rice include the selection of good cultivar, rational fertilization and water management, the promotion of mechanized production, and prevention and control of diseases, insect and weed.%武夷山风景区周边盆地属中亚热带气候,水稻安全生长季235d,积温5368℃,可一年两熟,种植晚熟高产杂交稻品种的热量一季有余,两季不足。适时早播,调节单季稻和再生稻头季开花结实期与七八月份光温高值期重合,再生季避过早秋冷害,是稻作增产增收的关键举措。高产配套技术有选用良种、合理施肥管水、推行机械化生产和防控病虫草害。

  14. 籼型杂交稻八个行向栽培试验初报%Preliminary Report on the Effect of Eight Cultivation Orientations on Indica Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    潘典进; 龙永红; 黄春祥; 龚元春; 袁三洋; 高圣良; 罗传贵; 刘丰国; 詹红菊; 袁建国; 杨玲丹; 潘琴; 王军华

    2013-01-01

    The high photosynthetic efficiency cultivation of indica hybrid rice was obtained through changing the direction of cultivation and optimizing the linewidth. Based on the wind types in meteorology ,set 22.5° interval for four main directions and eight cultivation orientations ,combined with wide and narrow lines to deal with the cultivation of indica hybrid rice. The test results indicated that the optimized condition was “two cis and one combination”,Which meant the cultivation orientation was in the same direction as the noon sun and grew in the direction of the south westerly or north-south wind during the whole growth period ,and the planting was a combination of wide and narrow lines (50-30 cm ). This technique could increase the light efficiency and therefore increased the yield and disease-resistant performance.%通过改变栽培方向及优化种植行距能够提高籼型杂交稻的光合效率。以气象学风向类型为依据,设22.5°间距、4类8个行向处理,并配以宽窄组合行距为基础,得出本地水稻栽培优化行子为“二顺一组”,即行向午时顺光、生长期全程顺风的南偏西或近南北行向和宽窄行(50-30 cm)组合栽插,其可以提高水稻光合效率,增强抗性,从而提高产量。

  15. Levels and patterns of nucleotide variation in domestication QTL regions on rice chromosome 3 suggest lineage-specific selection.

    Directory of Open Access Journals (Sweden)

    Xianfa Xie

    Full Text Available Oryza sativa or Asian cultivated rice is one of the major cereal grass species domesticated for human food use during the Neolithic. Domestication of this species from the wild grass Oryza rufipogon was accompanied by changes in several traits, including seed shattering, percent seed set, tillering, grain weight, and flowering time. Quantitative trait locus (QTL mapping has identified three genomic regions in chromosome 3 that appear to be associated with these traits. We would like to study whether these regions show signatures of selection and whether the same genetic basis underlies the domestication of different rice varieties. Fragments of 88 genes spanning these three genomic regions were sequenced from multiple accessions of two major varietal groups in O. sativa--indica and tropical japonica--as well as the ancestral wild rice species O. rufipogon. In tropical japonica, the levels of nucleotide variation in these three QTL regions are significantly lower compared to genome-wide levels, and coalescent simulations based on a complex demographic model of rice domestication indicate that these patterns are consistent with selection. In contrast, there is no significant reduction in nucleotide diversity in the homologous regions in indica rice. These results suggest that there are differences in the genetic and selective basis for domestication between these two Asian rice varietal groups.

  16. Selection Under Domestication: Evidence for a Sweep in the Rice Waxy Genomic Region

    Science.gov (United States)

    Olsen, Kenneth M.; Caicedo, Ana L.; Polato, Nicholas; McClung, Anna; McCouch, Susan; Purugganan, Michael D.

    2006-01-01

    Rice (Oryza sativa) was cultivated by Asian Neolithic farmers >11,000 years ago, and different cultures have selected for divergent starch qualities in the rice grain during and after the domestication process. An intron 1 splice donor site mutation of the Waxy gene is responsible for the absence of amylose in glutinous rice varieties. This mutation appears to have also played an important role in the origin of low amylose, nonglutinous temperate japonica rice varieties, which form a primary component of Northeast Asian cuisines. Waxy DNA sequence analyses indicate that the splice donor mutation is prevalent in temperate japonica rice varieties, but rare or absent in tropical japonica, indica, aus, and aromatic varieties. Sequence analysis across a 500-kb genomic region centered on Waxy reveals patterns consistent with a selective sweep in the temperate japonicas associated with the mutation. The size of the selective sweep (>250 kb) indicates very strong selection in this region, with an inferred selection coefficient that is higher than similar estimates from maize domestication genes or wild species. These findings demonstrate that selection pressures associated with crop domestication regimes can exceed by one to two orders of magnitude those observed for genes under even strong selection in natural systems. PMID:16547098

  17. Biochar amendment reduced methylmercury accumulation in rice plants.

    Science.gov (United States)

    Shu, Rui; Wang, Yongjie; Zhong, Huan

    2016-08-01

    There is growing concern about methylmercury (MeHg) accumulation in rice grains and thus enhanced dietary exposure to MeHg in Asian countries. Here, we explored the possibility of reducing grain MeHg levels by biochar amendment, and the underlying mechanisms. Pot (i.e., rice cultivation in biochar amended soils) and batch experiments (i.e., incubation of amended soils under laboratory conditions) were carried out, to investigate MeHg dynamics (i.e., MeHg production, partitioning and phytoavailability in paddy soils, and MeHg uptake by rice) under biochar amendment (1-4% of soil mass). We demonstrate for the first time that biochar amendment could evidently reduce grain MeHg levels (49-92%). The declines could be attributed to the combined effects of: (1) increased soil MeHg concentrations, probably explained by the release of sulfate from biochar and thus enhanced microbial production of MeHg (e.g., by sulfate-reducing bacteria), (2) MeHg immobilization in soils, facilitated by the large surface areas and high organosulfur content of biochar, and (3) biodilution of MeHg in rice grains, due to the increased grain biomass under biochar amendment (35-79%). These observations together with mechanistic explanations improve understanding of MeHg dynamics in soil-rice systems, and support the possibility of reducing MeHg phytoaccumulation under biochar amendment. PMID:27045620

  18. 荷兰豆—优质稻—甘薯高产栽培技术%Pea Pods-Quality Rice-Sweet Potato High Yield Cultivation Techniques

    Institute of Scientific and Technical Information of China (English)

    王来清; 赖德才

    2012-01-01

    Pea pods-qality rce-sweet potato high yield cultivation techniques summed up through the"Whole City Money-Grain Harvest Competition"practice that launched by Sanming municipal government,was an efficient planting pattern suitable for extension in Qingliu county.High yield cultivation techniques for pea pods,high quality rice,sweet potato were briefly introduced in this paper.%荷兰豆—优质稻—甘薯高产栽培技术是三明市政府组织的全市粮钱丰收竞赛活动实践中总结出来的适应清流县推广的高效种植模式,文章就荷兰豆、优质稻、甘薯的高产栽培技术作简要介绍。

  19. 不同水直播方式水稻植株抗倒特性研究%Lodging Resistance of Rice under the Different Pattern of Water Direct-seeding Cultivation Method

    Institute of Scientific and Technical Information of China (English)

    许轲; 唐磊; 郭保卫; 张洪程; 霍中洋; 戴其根; 魏海燕

    2014-01-01

    为研究不同水直播方式水稻植株倒伏的差异,在稻麦两熟制下,以2个常规粳稻(常农粳7号、超级稻南粳44)和2个杂交粳稻品种(甬优2638、甬优7号)为试材,设置水直播点播和条播2种方式,于齐穗后30 d,研究了不同直播方式高产水稻植株地上部分各节间抗倒伏能力的差异,并对倒伏指数、抗折力与茎秆主要物理性状进行相关分析。结果表明,条播方式水稻倒伏比例较大,水稻植株基部第2,3节间抗折力和弯曲力矩,点播方式显著高于条播方式;条播方式倒伏指数显著较高。点播方式水稻株高、重心高度高于条播方式,但相对重心高度低于条播方式。点播方式水稻基部第1,2节间长度显著小于条播方式,基部3个节间的茎秆内径长均显著高于条播方式,除基部第1节间外,基部第2,3节间外径长和茎壁厚度点播方式显著高于条播方式。点播方式基部第1,2节间单位节间干质量显著高于条播方式。上述茎秆性状在不同类型品种间有较大差异。直播水稻茎秆的抗折力和倒伏指数与水稻茎秆基部节间长、茎壁厚、节间充实度等性状密切相关。点播方式水稻具有基部节间短而粗、茎壁较厚,且充实度好的特点,是其抗倒伏能力强的直接原因。%In recent years, cultivation area of direct-seeding rice in Jiangsu Province and nearby regions has been expanding rapidly,the stronger lodging resistance of culm is the key aspect to high yield and excellent-quali-ties,but the specific research on the influencing factors of lodging resistance is little in direct-seeding rice. At thirty days after heading,a field experiment was conducted with four varieties,conventional rice Changnongjing 7,super rice Nanjing 44,hybrid rice Yongyou 2638 and Yongyou 7,to investigate the differences of rice-stem lodging resist-ance between two direct-seeding cultivation methods,named hole seeding and seeding in drill

  20. Radioisotopes and rice

    International Nuclear Information System (INIS)

    To stimulate research into problems of rice cultivation, the International Atomic Energy Agency has placed several research contracts with agricultural institutes in some of its Member States. Some of these research projects deal with problems of soil-plant relations and fertilization, and rice is one of the main crops on which studies are being made. A panel of experts convened by the Agency met in Vienna in May this year to discuss some of the outstanding problems in the uses of radioisotopes in soil-plant relations and fertilization studies, and problems concerning rice were among the principal subjects considered. In a paper presented at the panel meeting. Professor S. Mitsui, of the University of Tokyo, reviewed some of the main uses of radioisotopes in studying problems of rice soils and rice cultivation and suggested several specific topics in this field which could be investigated by isotope techniques

  1. Consumer preference mapping for rice product concepts

    NARCIS (Netherlands)

    Suwannaporn, P.; Linnemann, A.R.; Chaveesuk, R.

    2008-01-01

    Purpose - Rice consumption per capita in many Asian countries is decreasing constantly, but American and European citizens are eating more rice nowadays. A preference study among consumers was carried out with the aim of determining new rice product characteristics in order to support export of Thai

  2. Consumer Preferences and Buying Criteria in Rice: A Study to Identify Market Strategy for Thailand Jasmine Rice Export

    NARCIS (Netherlands)

    Suwannaporn, P.; Linnemann, A.R.

    2008-01-01

    Rice consumption per capita in many Asian countries decreased, but it is consumed more in non-rice-eating countries. This study aimed to investigate consumer preferences and attitudes toward Jasmine rice among consumers in target rice export countries to identify opportunities and strategic implicat

  3. Planting Performance and High-yielding Cultivation Techniques of Hybrid Rice Combination Yiyou 673 in Anxi Country%优质超级稻宜优673在安溪种植表现及高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    肖全省

    2014-01-01

    Yiyou 673, derived from the CMS line Yixiang 1A and a restorer line Fuhui 673, was a new hybrid rice combination developed by Rice Research Institute, Fujian Academy of Agricultural Sciences. It was registered and released in 2006 in Fujian province. Yiyou 673 was introduced and planted in Anxi county of Fujian province for extensive adaptability, rice quality, high and stable yield. In this paper, we introduced planting performance and high-yielding cultivation techniques of Yiyou 673.%宜优673是福建省农业科学院水稻研究所用不育系宜香1A与恢复系福恢673配组而成的三系杂交水稻品种,于2006年通过福建省品种审定。在安溪县种植表现丰产、稳产、米质优、后期转色好等特点。介绍了宜优673在安溪县种植表现及高产栽培技术。

  4. Development of labor saving operation technique by making large scale paddy field and direct seeding cultivation of rice in Tohoku district [Japan], 2: Development of technique for automatic precision laser-levelling system

    International Nuclear Information System (INIS)

    1) Preparation for large large paddy fields and utilization of direct rice seeding cultivation are expected to be the key technologies for the low cost and labor saving large farm rice cultivation. To achieve this, the technique of land leveling for field operations have to be developed. A precise land leveling operation by a wheel tractor with laser-beam emitter and recover in a wet paddy field are developed. 2) The automatic measurement system of a rice paddy field surface level by a tractor that we developed was highly practical. After measured data ate stored in a memory of hand-held computer the standard deviation of a field height value is shown on the display. Also, measured data are exported to the personal computer and by RC232C, the contour map of the paddy field is draw quickly, which is useful for the land leveling work. 3) Considering the relation between rice seed germination and water depth in the field, the preciseness of the field leveling for direct rice seeding is required to be under 1.5cm of standard deviation (s.d.). To realize this preciseness, a prototype leveling aparatus consisting a laser emitter, a laser receiver and dry land leveler pulled by a tracter, was developed and was tested the performance. The results of land leveling test at a field of 1 ha indicated that the elevation difference of the field of 16cm was improved to that of 92% of +- 2.5cm (1.58cm s.d.) after leveling work. The working efficiency was 0.57hour/10a. For a precise leveling work, the of the soil water content should be under the plastic limitation, under which less amount of soil adoheres to the blade of the leveler. The performance tests of the laser assisted leveling apparatus for a paddy harrowing work revealed that for an accurate operation only a blade should be controlled by a hydraulic cylinder according to a laser beam. Since large amount of soil can not be handled by the apparatus, the leveling for a paddy harrowing work is recommended for a fine leveling

  5. Origin of Weedy Rice as Revealed by Hybridizations among Cultivated Rice and its Wild Relatives%栽培稻及其近缘野生种间杂交揭示杂草稻的起源

    Institute of Scientific and Technical Information of China (English)

    许红云; 陈丽娟; 熊海波; 朱骞; 石瑜敏; 王威豪; 刘百龙; 徐家星; 文建成; 李东宣

    2012-01-01

    通过水稻种间、亚种间和品种间的杂交,在套袋隔离和自然授粉两种条件下,对其杂交亲本主要农艺性状类型及杂交后代群体中杂草稻发生频率、类型及主要特征以及杂草稻的发生趋势进行调查分析,直接验证和重演杂草稻起源的主要路径.杂草稻的主要特征为:颖壳褐色或金色,种皮红色,散穗、易落粒,中长芒或无芒.结果表明,如果以近缘野生种为亲本,在其F2群体中比较容易发生类似杂草稻的单株;杂交组合中杂草稻出现频率的大小依次为:杂草稻或野生稻/粳稻(44.16%)>杂草稻或野生稻/籼稻(27.84%)>籼稻/粳稻(3.30%)>籼稻/籼稻(1.41%)>梗稻/粳稻(0).这一结果显示杂交亲本间遗传差异越大,在后代中出现杂草稻类型植株的频率就越高.套袋条件下,后代中杂草稻出现的频率为10.70%,而不套袋情况下为4.90%.%The objectives of this study are to explore the occurrence and development of weedy rice by investigating the frequency of weedy rice, which occurred in the progenies of crosses amount wild rice species, typical weedy rice,rice subspecies and cultivars. The results of this study indicated that wild and weedy rice showed brown or golden color of glum with or without awns and red pericarp, spreading type of panicles and shattering easily. A-nalysis for qualitative characteristics in F2 population suggested that the hybrid combinations with one of its parental line, which genetically nearer to its ancestry lines, would be prone to produce more weedy rice like plants. The frequencies of occurrence of weedy rice like plants in F2 population varied depending on the genetic similarities between the two parents. The more different between two parental lines are the more frequent weedy rice like plants produced. The sequence is as: weedy rice or wild rice/Japonica (44. 16%) > weedy rice or wild rice/Indica (27.84%) >Indica/Japonica (3. 30%) > Indica/Indica( 1. 41

  6. Human Activity Influenced by Climate Change: Response of Spatial Distribution of Ancient Rice Cultivation in China to Climate Change during the Early to Mid-Holocene%气候条件限制下的人类活动——全新世早中期中国栽培水稻分布的变化对气候变迁的响应

    Institute of Scientific and Technical Information of China (English)

    张玲; 梅孙华; 王培敏

    2013-01-01

    Rice cultivation is one of the important human activities in the Neolithic period, and the link between its development and climate change is essential for studies on rice domestication and civilization. Data of archaeological sites with excavated rice remains in China during the early to mid-Holocene (12 000 -5 500 aBP) were compiled, and the link between rice cultivation and climate change was analyzed. The results showed that the origination and early development of rice cultivation were mainly distributed on the edge of regions where wild rice distributed. The early development of rice cultivation during the early to mid-Holocene was also mainly influenced by climate change.%水稻栽培是新石器时代重要的人类活动之一,其发展同气候之间的联系是研究稻作起源和文明发展的一个关键问题.该文利用搜集到的全新世早中期(12 000~5 500 aBP)中国的栽培水稻出土遗址点数据,对全新世早中期中国水稻栽培同气候的关系进行了分析.结果表明,栽培水稻的起源与初期发展具有“边缘效应”,即分布于野生稻分布的边缘地带;而其早期的发展和分布也具有类似的特征,即主要受气候因素的影响,因此全新世早中期栽培水稻的分布范围的变化受到气候条件的限制,该时期环境变化受气候“主导”.

  7. 播种期对轻简栽培方式再生稻源库关系的影响%Effects on Source-sink of Ratoon Rice Under Simplified Cultivation of Different Seeding Stages

    Institute of Scientific and Technical Information of China (English)

    柳开楼; 秦江涛; 张斌

    2012-01-01

    为建立轻型化的再生稻高产技术体系,并在赣东北种植和推广再生稻,于2009-2010年在江西省余江县开展了再生稻轻简栽培和播期试验,分析了源库关系、生物量和氮积累量以及产量等指标.结果表明,与人工栽插相比,直播和抛秧在头季稻后期和再生稻的叶面积指数显著较低,降幅为5.1% ~ 57.8%,在头季稻中其实粒数分别比人工栽插减少了25.3% ~41.2%,再生稻中分别降低了9.9%~46.5%,再生稻中生物量分别比人工栽插减少了23.7%~53.2%,氮积累量分别降低了20.0%~54.4%.这表明直播和抛秧等轻简栽培方式的源小库弱,从而导致其再生稻产量比人工栽插降低了30.1%~ 35.1%.不同播期之间是较早播种的再生稻占用的温光资源较多,3月下旬和4月上旬播种的处理在头季稻和再生稻的源库关系、生物量和氮积累量以及产量均显著高于较晚播种的处理,因此通过提前播种可以优化直播和抛秧的源库关系,提高再生稻的产量.%The high-yield ratoon rice system under simplified cultivation (direct-seeding and seedling-throwing) was studied by the experiment of different planting patterns and seeding stage in 2009 and 2010 at Yujiang country, Jiangxi Province, and the source-sink characteristics, biomass, nitrogen accumulation and yield of ratoon rice were also analyzed. The results showed that leaf area index of direct-seeding and seedling-throwing in main ratoon rice were lower than transporting by 5.1% - 57.8%. In main rice, grain numbers were decreased than transplanting by 25.3% - 41.2% in direct-seeding and seedling-throwing, and reduced by 9.9% - 46.5% in ratoon rice. Biomass of direct-seeding and seedling-throwing were decreased by 23.7% - 53.2% in ratoon rice, and nitrogen accumulation were reduced by 20.0% -54.4%. This indicted that grain yield of direct-seeding and seedling-throwing were lower than transporting by 30.1% - 35

  8. IRRI/ADB Project on hybrid rice

    Institute of Scientific and Technical Information of China (English)

    Peng; Jiming

    2006-01-01

    @@ Hybrid rice technology has made a significant progress in recent years in more than twenty rice-growing countries. The Asian Development Bank (ADB) provided funds for International Rice Research Institute (IRRI) to support the project of Sustaining Food Security in Asia through Development of Hybrid Rice Technology 2002-2004 mainly practiced in nine countries, such as Bangladesh, India, Indonesia, Korea, Myanmar, Philippines, Sri Lanka, Thailand and Vietnam.

  9. Study on Different Centers of Origin of Asian Cultivated Rice%亚洲栽培稻分散起源的研究

    Institute of Scientific and Technical Information of China (English)

    黄燕红; 才宏伟; 王象坤

    2003-01-01

    分析中国、东南亚和南亚的96份普野的12个等位酶位点,及885份地方品种的10个酶位点的遗传多样性.结果表明,中国与南亚普野和栽培稻在Est-2、Est-10、Mal-1、Cat-1四个位点发生了地理分化.中国普野以Acp-12、Acp-20、Amp-22、Est-20、Cat-12、Mal-11基因型为主,是偏粳型.南亚普野以Acp-12、Acp-20、Amp-22、Est-21/Est-20、Cat-11、Mal-12基因型为主,是偏籼型.中国和南亚是两个独立的稻作起源中心.

  10. The Puzzle of Rice Domestication

    Institute of Scientific and Technical Information of China (English)

    Tao Sang; Song Ge

    2007-01-01

    The origin of cultivated rice has puzzled plant biologists for decades. This is due, at least in part, to the complex evolutionary dynamics in rice cultivars and wild progenitors, particularly rapid adaptive differentiation and continuous gene flow within and between cultivated and wild rice. The long-standing controversy over single versus multiple and annual versus perennial origins of cultivated rice has been brought into shaper focus with the rapid accumulation of genetic and phylogenetic data. Molecular phylogenetic analyses revealed ancient genomic differentiation between rice cultivars, suggesting that they were domesticated from divergent wild populations. However, the recently cloned domestication gene sh4, responsible for the reduction of grain shattering from wild to cultivated rice, seems to have originated only once. Herein, we propose two models to reconcile apparently conflicting evidence regarding rice domestication. The snow-balling model considers a single origin of cultivated rice. In this model, a core of critical domestication alleles was fixed in the founding cultivar and then acted to increase the genetic diversity of cultivars through hybridization with wild populations. The combination model considers multiple origins of cultivated rice. In this model, initial cultivars were domesticated from divergent wild populations and fixed different sets of domestication alleles. Subsequent crosses among these semi-domesticated cultivars resulted in the fixation of a similar set of critical domestication alleles in the contemporary cultivars. In both models, introgression has played an important role in rice domestication. Recent and future introgression of beneficial genes from the wild gene pool through conventional and molecular breeding programs can be viewed as the continuation of domestication.

  11. Commercialization of transgenic rice in China: potential environmental biosafety issues

    OpenAIRE

    Bao-Rong Lu; Qiang Fu; Zhicheng Shen

    2008-01-01

    The development and commercialization of transgenic rice with novel traits in China may offer more opportunities for promoting rice productivity. Owing to the significance of rice as a major food crop in China, the enhancement of rice production is important for national food security. If left unaddressed, the potential biosafety concerns over the extensive release and commercial cultivation of transgenic rice may hamper the development and application of this technology in rice improvement. ...

  12. 稻鸭共作系统中稻飞虱及主要捕食性天敌类群之间的关系%Relationship Among Rice Planthoppers and Main Predatory Arthropods in Rice-Duck Integrated Cultivation System

    Institute of Scientific and Technical Information of China (English)

    秦钟; 章家恩; 张锦; 骆世明

    2012-01-01

    以生态位理论为依据,研究了施用化肥(化肥区)、稻鸭共作(稻鸭区)和无化肥农药(对照区)3个处理区中稻飞虱与主要捕食性天敌类群的数量及消长动态、时间生态位特征,并进行了灰色关联度分析.结果表明,3个处理区稻飞虱与主要捕食性天敌类群的数量、时序特征、时间生态位宽度与重叠指数等均存在不同程度的差别.稻鸭共作使稻飞虱发生高峰期的数量、主要捕食性天敌总量降低,与化肥区、对照区相比,益害比分别下降了1.72%和26.14%;与化肥区相比,稻鸭区除瓢虫外,其他捕食性天敌类群的生态位宽度均降低2.14%~35.77%,多数天敌之间如肖蛸与隐翅虫、园蛛与瓢虫等的生态位重叠度增加,但瓢虫、球蛛对稻飞虱的跟随效应和控制潜能加大,一定程度上弥补了天敌数量减少、对稻飞虱影响减弱等不足,使得晚稻整个观测期内稻飞虱的总数比化肥区下降23.70%.不同稻作模式、不同类型的捕食性天敌与稻飞虱的关联性不同,稻鸭区中瓢虫、狼蛛和球蛛对稻飞虱影响较大.%Based on the ecological niche theory, the population compositions and dynamics, time niche of planthoppers and main predatory arthropods were investigated in three experimental treatment plots; chemical fertilizer utilization plot, rice-duck integrated cultivation plot and no chemical pesticides/fertilizer application plot, and grey relational grade analysis was conducted in the meanwhile. The results indicated that differences in individual numbers, temporal variation characteristics, temporal niche breadth and overlap index lot rice planthoppers and the main predatory arthropods varied to various degrees among the three treatment plots. The number of rice planthoppers in its peak stage as well as the total individual number of the main predatory arthropods decreased. Compared with the chemical fertilizer utilization plot and the control plot

  13. 黑龙江省主栽糯稻遗传背景研究%Research on Genetic Background of Main Cultivated Glutinous Rice in Heilongjiang Province

    Institute of Scientific and Technical Information of China (English)

    刘宇强; 刘晴; 高世伟; 聂守军; 谢树鹏; 魏中华; 王翠玲; 刘立超

    2016-01-01

    选取黑龙江省近年审定的糯稻品种,对其遗传背景进行分析,试图挖掘其系谱中的骨干亲本,为糯稻品种的选育和改良提供理论依据。结果表明,大部分通过审定的糯稻品种都含有日本水稻的血缘;一些骨干亲本能够直接育成或衍生出糯稻品种,为优秀的糯稻品种选育奠定了基础。今后,应加强骨干亲本的筛选和利用,以为糯稻品种的选育和改良提供帮助。%The genetic backgrounds of main glutinous rice were analyzed in this study, which were approved in recent years in Hei-longjiang Province. The author tries to find out the mainstay parents in pedigree, provides theoretical basis for glutinous rice variety breeding and improvement. The results showed that most of the glutinous rice approved contain the consanguinity of Japanese rice, some mainstay parents can directly breed or derived glutinous rice varieties and lay the foundations for the breeding of glutinous rice. The authors suggested that future breeding program, emphysives on the selection and utilization of mainstay parents.

  14. SRI Cultivation in Andhra Pradesh : Achievements, Problems and Implications for GHGs and Work

    OpenAIRE

    Duvvuru, Narasimha Reddy; Motkuri, Venkatanarayana

    2013-01-01

    Strategies and solutions to meet the challenges of GHGs call for new methods and technologies. Potential options for the rice industry sector to contribute to the mitigation of, and adaptation to, climate change by increasing rice production in a physically sustainable manner are attracting growing research interest. One such area of interest is the new method of rice cultivation: the System of Rice Intensification (SRI). SRI is an innovative approach to rice cultivation but not a technology ...

  15. Comparative Study on Triangle System of Rice Intensification(SRI)with Square System of Rice Intensification,Throwing-transplanted Rice and Traditional Cultivation%水稻三角形强化栽培与正方形强化栽培、抛秧栽培、常规栽培的比较研究

    Institute of Scientific and Technical Information of China (English)

    刘述斌; 李旭毅; 许远明; 马均

    2012-01-01

    The characters of growth and development and the formation of grain yield in triangle SRI were studied in this paper to supply the practice basis in rice production. The triangle SRI with different planting density was compared with square SRI, throwing-transplanted rice and traditional cultivation under different level of nitrogen supplied in order to study the changes of relationship between population and individual of rice, characters of formation and translocation in population source-sink, plant senescence in later growth stage and yield formation characters. The results indicated that, triangle SRI and throwing-transplanted rice harvest was higher than grain yield by increasing more number of effective panicle and decreasing individual quality to some extent, but the triangle SRI with suitable density had more advantage than throwing-transplanted rice and square SRI obviously. Square SRI also obtained high grain yield by improving the individual growth and its yield components if population was enough. Triangle SRI and square SRI with suitable density had bigger LAI, more accumulation of matter, higher export amount and export percentage and translocation percentage of stems and sheaths to panicle than throwing-transplanted rice and traditional cultivation in its late growth period. Triangle SRI and square SRI with suitable density had higher productive potential. The grain yield of high N supplied (225 kg/hm2) was higher by 6.36% than that of medium N supplied (150 kg/hm2). It indicated that, proper increase of N supplied level was favor of higher grain yield for SRI.%为了探讨三角形强化栽培在生长发育及产量形成等方面的特点,找出最具增产潜力的栽培方式和技术,为其今后在水稻生产应用中提供实践依据.试验以‘D优527’为材料,研究了在不同施氮水平和密度下,水稻三角形强化栽培与正方形强化栽培、抛秧栽培、常规栽培水稻群体和个体关系、群体库源建成特

  16. 粳型巨胚稻西巨胚1号品种特性与栽培技术研究%Study on Variety Characteristics and Cultivation Techniques of Giant Embryo NO. 1 Japonica Rice

    Institute of Scientific and Technical Information of China (English)

    张荣萍; 戴红燕; 蔡光泽

    2011-01-01

    [目的]研究西巨胚1号品种特性及在攀西高原稻区高产栽培技术.[方法]通过对西巨胚1号、合系22-2、昌米011在生育期、农艺性状、分蘖力、穗部性状和品质性状等方面进行对比分析,从播期、播量、栽插密度、水肥管理、病虫害防治等方面总结西巨胚1号在攀西高原稻区栽培技术要点.[结果]西巨胚1号在攀西高原稻区种植中表现出胚大、米质较优、抗病、抗倒、适应性强等特点.适宜在攀西高原地区3月下旬播种,用种量为60~75 kg/hm,基本苗120万~150万株/hm,早施分蘖肥,重施基肥,补施穗粒肥,科学灌水,注意病、虫、草、鸟害防治.[结论]该研究为进一步改进西巨胚1号栽培技术提供理论和生产实践参考.%[ Objective ] The paper was to study the variety characteristics of Giant Embryo No. 1 Japonica Rice and its high yield cultivation techniques in Panxi plateau rice region. [ Method ] Giant Embryo No. 1, Hexi 22-2 and Changmi 011 were compared and analyzed from the aspects of growth stage,agronomic traits,tillering ability,panicle and quality traits,and the cultivation techniques of Giant Embryo No. 1 in Panxi plateau rice region were summarized in the aspects of sowing time, sowing rate, planting density, water and fertilizer management and pest and disease control. [ Result ] Giant Embryo No. 1 showed the characteristics of big embryos, excellent grain quality, disease resistance, lodging resistance and strong adaptability in the cultivation in Panxi plateau rice region,which was suitable for sowing in late March in the region. The seed rate was 60 -75 kg/hm2 ,basic seedlings were 1 200 000 - 1 500 000/hm2 with early application of tillering fertilizer and heavy application of base fertilizer,grain fertidizer should also be supplemented with scientific irrigation,and diseases,insects,grass,bird damage should be paid attention. [ Conclusion ] The study provided the reference for theoretical and

  17. 谷优769在建阳作烟后稻种植表现及高产栽培技术%Planting Performance and High-yielding Cultivation Techniques for Hybrid Rice Combination Guyou 769 as Post-tobacco Rice at Jianyang City

    Institute of Scientific and Technical Information of China (English)

    丁巧莲

    2015-01-01

    A late new hybrid rice combination Guyou 769 was developed by Nanping Institute of Agricultural Sciences. It was tested and demonstrated as post-tobacco rice in three years at Experimental Farm of Nanping Agriculture School, showing moderate growth duration, uniform population, high yield, good plant colour at maturity, and strong resistant blast. The planting performance and high-yielding cultivation techniques for Guyou 769 as post-tobacco rice at Jianyang were summarized.%谷优769是由福建省南平市农科所选育的杂交晚稻新品种,在南平市农校试验农场作烟后稻,经3a的试验和示范种植,表现生育期适中,群体整齐,丰产性好,熟期转色好,稻瘟病抗性强等特性。总结了谷优769在建阳作烟后稻种植表现及高产栽培技术。

  18. Transfer to rice

    International Nuclear Information System (INIS)

    One of the critical foods for the intake of radionuclides by humans is rice (Oryza sativa L.), which is the dominant staple food crop in humid tropical and sub-tropical countries across the globe. Cultivation methods have important effects on plant uptake of radionuclides from soil. Most rice is produced under flooded conditions, i.e. in fields with a water layer of 5-15 cm deep on soil. This is unlike the situation in unsaturated fields where the soil conditions are significantly different, meaning that the soil-to-rice transfer factors (Fvs) need to be discussed separately from Fv values of other cereals grown under unsaturated field conditions. In this section, rice refers to the crop grown on wet paddy fields; since water management is the dominant method for rice cultivation this is the most common type. Rice Fv values were collected from papers in international journals, books and proceedings with peer reviewing processes and Fv values based on dry weight rice grain were summarized here. Fv data for fallout isotopes (e.g. 90Sr and 137Cs), neutron activation products (e.g. 54Mn, 60Co, etc.) or naturally existing radionluclides (e.g. 210Pb, 226Ra, 238U, etc.) and those for naturally existing stable elements under agricultural field conditions were listed. (author)

  19. 水果玉米-优质稻-西兰花一年三熟高优栽培技术%Annual Triple Cropping High Quality Cultivation Techniques for Fruit Corn-Quality Hybrid Rice-Broccoli

    Institute of Scientific and Technical Information of China (English)

    叶敬用; 曾春华; 林锦星; 吴文革

    2015-01-01

    In order to make the best of climate resource advantage, Pinghe county has explored planting pattern in field structure in 2010-2014, confirming that annual triple cropping planting pattern of Fruit corn-quality hybrid rice-broccoli is suitable for development and extension in Pinghe county and has good economic benefit. The annual triple cropping key high quality cultivation techniques of Fruit corn-quality hybrid rice-broccoli at Northwest Town of Pinghe county were introduced.%为充分利用气候资源优势,2010—2014年平和县探索大田结构种植模式,确定水果玉米—优质稻—西兰花一年三熟种植模式适合在平和县发展推广,效益佳。介绍了水果玉米—优质稻—西兰花一年三熟在平和县西北部乡镇高优栽培技术要点。

  20. Effects of Different Light Cultivation on Rice Growth, Yields and Economic Benefits in Northeast Area of Jiangxi Province%赣东北双季水稻轻型种植和耕作模式评价

    Institute of Scientific and Technical Information of China (English)

    刘金花; 秦江涛; 张斌; 夏桂龙; 陆金贵; 甘三芽; 余瑞新

    2012-01-01

    Rice cultivation technology has been developed rapidly in recent years, but its comparison with traditional artificial transplantation is still scarce, which leads to an argument whether the light cultural technique can produce high yields. This study was carried out to evaluate the effects of three planting patterns (direct seeding (DS), throwing seeding (TS) and transplantation (TP)) and mechanized deep tillage and shallow tillage with straw returning on the performance of two year early and late rice growth, yields and economic benefits at Yujiang in the northeast of Jiangxi province. The results showed that, compared with TP, DS shortened the rice growth period: both DS and TS reduced the tiller numbers per hill, the aboveground total biomass per hill, the percentage of productive tillers and the grain number per spike, but enhanced leaf area index (LAI) and panicle per unit area. Except TS increased the late rice yields in 2009 year significantly, compared with DS and TP, the yields of the other three seasons were not significantly different in the three cultivation methods. Compared with the traditional deep tillage, the shallow tillage significantly increased the tiller numbers per hill and the aboveground total biomass per hill during the growth stage, but it decreased LAI at the late growth and the percentage of productive tillers which therefore caused the lower production. Compared with straw output, rice straw mechanical returning increase the spike rate and the accumulation of dry matter, thus improved rice yields in the four seasons, and the rice yield significantly increased along with the time. According to comprehensive analysis, the highest yield of the early rice was from the treatment with deep tillage, direct seeding and straw retuning, and that of the late rice from the treatment with deep tillage, throwing seeding and straw retiming simultaneously. While form the economic efficiency point of view, compared with the combination patterns of

  1. 中国杂交水稻在巴西的试种表现及高产栽培技术%Experimentation of Chinese Hybrid Rice in Brazil and Its High-yielding Cultivation Techniques

    Institute of Scientific and Technical Information of China (English)

    刘法谋; 黄大辉; 方远祥

    2012-01-01

    2011年9月至次年2月,隆平高科选择6个中国杂交水稻组合在巴西戈亚斯州北部Araguaia流域进行了品比试验,结果6个组合单产为8.07~9.15 t/hm2,比当地对照品种Puita增产36.1% ~54.3%.结合当地水稻生产实际,从品种选择、发运、整地、种子处理、播种、田间肥水管理、综合防治病虫草鸟害等方面介绍了中国杂交水稻在巴西的高产栽培技术.%During September, 2011 and February, 2012, Yuan Longping High-Tech Agriculture Co. Ltd. Introduced 6 Chinese hybrid rice varieties into Brazil to conduct a yield trial in Araguaia, Goias with Puita, a local improved rice variety, as the control. The results showed that the average yields of the tested hybrids ranged from 8. 07 to 9. 15 t/hm2, 36. 1% and 54. 3% higher than that of the local check Puita. Based on the local conditions, the high-yielding cultivation techniques, including variety selection, seed export and transportation, land preparation, seed treatment and sowing, field management in irrigation and fertilization and integrated pest control, were proposed for hybrid rice production in Brazil.

  2. Conservation and utilization of rice genetic resources in China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Rice genetic resources presents variably in China. There are land races and wild species. cultivated lowland rice and upland rice, indica (Hsien) and japonica (Keng) riee. early, middle, and late rice as well as glutinous and non-glutinous rice. Up to February 2000, a total of 76, 646 rice accessions were catalogued,and 67. 444 base accessions were stored in the National Crop Gene Bank in the Institute of Crop Genetic Resources (ICGR) of the Chinese Academy of Agricultural Sciences, Beijing, China (Table 1). About 35,000 rice duplicates were stored in China National Rice Research Institute(CNRRI), Hangzhou, Zhejiang Province. China.

  3. Vietnamese rice exports: Do large destination markets stimulate?

    OpenAIRE

    Vu, Hanh Thi; Doan, Hung Quang

    2013-01-01

    What determines Vietnamese rice export flows? Data on rice export from Vietnam and its 124 destination markets in 2010 shows that high-income from agricultural sector of importing countries do not necessarily result in higher rice exports whereas exports tend to be higher to highly populated countries. In order to confirm the negative effect of the importing countries' GDP, We proceed to split the full sample into subsamples for Asian and non-Asian importing countries. While GDP covers the en...

  4. 栽培方式对粳型巨胚稻干物质积累和产量的影响%Effects of Cultivation Regimes on Dry Matter Accumulation and Grain Yield in Japonica Giant Embryo Rice

    Institute of Scientific and Technical Information of China (English)

    张荣萍; 马均

    2011-01-01

    为了研究不同栽培方式对粳型巨胚稻各器官干物质积累动态及产量构成的影响,用粳型巨胚稻新品系'西巨胚1号'为试验对象,以常规粳稻'合系22-2'作对照.采用淹水、旱种和垄畦3种栽培方式进行种植.大田的移栽规格为(20+14)cm×14cm宽窄行双行种植,每穴种2苗,采用随机区组设计,3次重复.详细记载生育进程;于孕穗期、齐穗期和成熟期每个处理取4穴测定其叶面积和干物质重;成熟后,每处理取10穴考种测其产量性状,全小区收割计产.结果表明,3种栽培方式中,垄畦栽培下巨胚稻植株的分蘖增多,茎叶干物质积累较多,有利于构建早期高产群体;生育后期延长了叶片的寿命,提高了干物质运转率,有效穗和稳粒数显著增加,从而提高了稻谷产量.因此,在巨胚稻生产中建议采用垄畦栽培以提高物质积累和运转和获得最大产量.%For the purpose of studying the effects of different cultivation regimes on dynamics of dry matter accumulation in organs and grain yield components of ‘Japonica Xi-giant embryo-1', the experiment studied the three different cultivation regimes of submerged irrigation, dry cultivation and ridge cultivation used ‘Japonica Xi-giant embryo-1' as experimental materials, conventional japonica rice ‘Hexi-22-2' as control. The transplanting size was (20+ 14) cm × 14 cm the seedling number two plants per hill. This experiment with randomized block design and three repeated. The results indicated that, under the ridge cultivation, the tillering and the dry matter accumulation of stems and leaves were increased, and it was beneficial to build the high-yielding population in early stage. The effective panicles number and grain number per spike were increased for delaying the senescence of leaf during late growth stage and promoting the transportation percentage of dry matter accumulation under the ridge cultivation. Finally, the grain yield was increased

  5. WHERE IS BASMATI RICE COMING FROM? A GLOBAL TRADE–RELATED OVERVIEW

    OpenAIRE

    Giraud, Georges; Pirzada, Syed Wajid H.

    2009-01-01

    Rice contributes on 20% towards human calorie intake of the world population and 30% of Asian population. Worldwide paddy rice crop was 668 million tonnes in 2008, while rice trade during the year was 30 million tonnes. Trade represents 7% of overall rice cropping. Basmati rice export counts for high value and low volume. Although Basmati crop is primarily from two countries, specific data related to Basmati export are scarce. Basmati trade constituted 8.3% of rice world trade during 2008, wi...

  6. Transcriptome population genomics reveals severe bottleneck and domestication cost in the African rice (Oryza glaberrima).

    Science.gov (United States)

    Nabholz, Benoit; Sarah, Gautier; Sabot, François; Ruiz, Manuel; Adam, Hélène; Nidelet, Sabine; Ghesquière, Alain; Santoni, Sylvain; David, Jacques; Glémin, Sylvain

    2014-05-01

    The African cultivated rice (Oryza glaberrima) was domesticated in West Africa 3000 years ago. Although less cultivated than the Asian rice (O. sativa), O. glaberrima landraces often display interesting adaptation to rustic environment (e.g. drought). Here, using RNA-seq technology, we were able to compare more than 12,000 transcripts between 9 O. glaberrima, 10 wild O. barthii and one O. meridionalis individuals. With a synonymous nucleotide diversity πs = 0.0006 per site, O. glaberrima appears as the least genetically diverse crop grass ever documented. Using approximate Bayesian computation, we estimated that O. glaberrima experienced a severe bottleneck during domestication. This demographic scenario almost fully accounts for the pattern of genetic diversity across O. glaberrima genome as we detected very few outliers regions where positive selection may have further impacted genetic diversity. Moreover, the large excess of derived nonsynonymous substitution that we detected suggests that the O. glaberrima population suffered from the 'cost of domestication'. In addition, we used this genome-scale data set to demonstrate that (i) O. barthii genetic diversity is positively correlated with recombination rate and negatively with gene density, (ii) expression level is negatively correlated with evolutionary constraint, and (iii) one region on chromosome 5 (position 4-6 Mb) exhibits a clear signature of introgression with a yet unidentified Oryza species. This work represents the first genome-wide survey of the African rice genetic diversity and paves the way for further comparison between the African and the Asian rice, notably regarding the genetics underlying domestication traits.

  7. Demand analyses of rice in Malaysia

    OpenAIRE

    Tey, (John) Yeong-Sheng; SHAMSUDIN Mad Nasir; Mohamed, Zainalabidin; Abdullah, Amin Mahir; Radam, Alias

    2008-01-01

    As a typical developing Asian county, the growth in per capita income generally brings to diversification in Malaysians food basket. The most significant observation is the falling in per capita consumption of rice with continuous growth of demand for wheat based products. The objective of this study is to estimate the demand elasticities of rice in Malaysia, focusing whether rice is an inferior good. By using data from Household Expenditure Survey 2004/2005, this study obtains demand elastic...

  8. Improvement Effects of Rice Straw Mixed with Biological Agent on Plastic Shed Continuous Cultivation Soil%稻草配施生物菌剂对大棚连作土壤的改良效果

    Institute of Scientific and Technical Information of China (English)

    韩玉珠; 宋述尧

    2012-01-01

    The decomposition characteristics in soil and the improvement effects of rice straw mixed with biological agent used in plastic shed continuous cultivation soil were studied. The results showed that, the decomposition of rice straw mixed with biological agent was rapidly in the beginning and then weaken. The decomposition efficiency of rice straw mixed with EM bacterium was higher. Soil capacity and solid fraction was decreased; soil moisture content and porosity was increased; and soil water infiltration was strengthened. The content of organic materials, total N, total P and available N, P and K was in-crensed. The pH and EC value of the soil decreased. The soil salinity was restrained to migrate to surface. The soil cation exchange ratio was increased; and the soil nutrient preserving capability was improved. The quantity of bacteria and action-mycetes and their ratio (B/F) increased. The plastic shed soil's continuous cultivation obstacle was relieved. From the comprehensive analysis of soil's improvement,0.8% rice straw mixed with 1.0% EM bacterium had great effect.%研究了稻草配合两种生物菌剂施入塑料大棚连作土壤后,在土壤中的分解特性及对连作土壤的改良效果.结果表明,稻草配施生物菌剂(EM菌、乐土菌)在大棚土壤中腐解,开始迅速,以后逐渐减缓,以稻草+EM菌处理腐解效率较高.稻草配施生物菌剂可降低土壤的容重和固相率,提高土壤的含水量和孔隙度,增加土壤通透性,改善了土壤结构;提高了土壤有机质、全氮、全磷含量及碱解氮、速效磷、速效钾含量,降低了土壤pH和EC,抑制了大棚土壤盐分的表聚,提高了土壤阳离子交换量,增强了土壤的保肥供肥能力;增加了土壤中细菌、放线菌的数量,B/F提高,可从根本上缓解大棚土壤连作的障碍.从大棚土壤改良效果的综合分析看,0.8%稻草与1.0%EM菌配施效果较好.

  9. Chloroplast DNA diversity in wild and cultivated species of rice (Genus Oryza, section Oryza). Cladistic-mutation and genetic-distance analysis.

    Science.gov (United States)

    Dally, A M; Second, G

    1990-08-01

    Using a novel nonaqueous procedure, chloroplast DNA was isolated from 318 individual adult rice plants, representing 247 accessions and the breadth of the diversity in section Oryza of genus Oryza. Among them, 32 different cpDNA restriction patterns were distinguished using the restriction endonucleases EcoRI and AvaI, and they were further characterized by restriction with BamHI, HindIII, SmaI, PstI, and BstEII enzymes. The differences in the electrophoretic band patterns were parsimoniously interpreted as being the result of 110 mutations, including 47 restriction site mutations. The relationships between band patterns were studied by a cladistic analysis based on shared mutations and by the computation of genetic distances based on shared bands. The deduced relationships were compared with earlier taxonomical studies. The maternal parents for BC genome allotetraploids were deduced. Within species, cpDNA diversity was found larger in those species with an evolutionary history of recent introgression and/or allotetraploidization. Occasional paternal inheritance and recombination of cpDNA in rice was suggested.

  10. Wheat products as acceptable substitutes for rice.

    Science.gov (United States)

    Yu, B H; Kies, C

    1993-07-01

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

  11. Effects of Cultivation Techniques on Selenium Increasing and Cadmium Decreasing in Rice%栽培措施对稻米增硒降镉效果研究

    Institute of Scientific and Technical Information of China (English)

    颜送贵; 邓正春; 郝界州; 江克平; 程泽新; 李斌; 唐玉梅; 刘兴海; 张兴江

    2014-01-01

    Excessive amounts of cadmium (Cd) in rice is a big threaten to food safety, which pose a direct health threat to humans. Selenium (Se) is an essential element for human health. Se has an antagonism against Cd and it promotes removing Cd from human body. Based on three years field tests, the author found an effective way to produce fine quality rice (Se-enrich and low Cd rice) in soils of grade II(Soil Quality Standard, total Cd in soil, 0.2~0.6 mg/kg). These comprehensive measures are described as follows:fer-tilize Ca-Mg-P after plowing, spread lime during draining and sunning the fields, apply deep water management at mature stage, and fertilize Se foliar-fertilizer at heading stage and milky stage.%稻米镉含量超标是确保粮食安全的重大隐患,威胁着人类健康;硒是人体必需元素,遍布人体所有器官,而且与镉有拮抗作用,能促使镉从人体内排泄。民以食为天,为人们提供富含硒而镉含量不超标的大米,已成为目前普遍的饮食新需求。笔者通过3年的试验研究证实,采取“推广撒施钙镁磷肥,晒田排水时撒施石灰,出穗期实施深水管理,破口抽穗期-乳熟期喷施富硒叶面肥”等综合措施,可以确保在镉含量二级背景值(镉含量0.2 mg/kg~0.6 mg/kg)的土壤中生产出食用安全的“富硒而镉不超标”大米。

  12. 谷优3301作中稻丰产栽培技术%High-yielding cultivation technique of Guyou3301 as mid-season rice

    Institute of Scientific and Technical Information of China (English)

    林光培

    2012-01-01

    This paper introduce field performance of Guyou3301 in the area with an elevation of 250-900 m in Pingnan County,Fujiang Province.It also summarized high-yielding cultivation technique of Guyou3301,including seedling-raising,transplanting,fertilizer and water management,insect and disease control.%介绍谷优3301在福建省屏南县海拔250~900 m区域的种植表现,从播种育秧、移栽、肥水管理、病虫防治等方面总结其丰产栽培技术。

  13. Plastic film mulching cultivation decrease absorption of manganese and improve its use efficiency in upland and paddy rice%覆膜旱种降低水、陆稻锰素吸收提高锰素利用效率

    Institute of Scientific and Technical Information of China (English)

    张亚洁; 施恰恰; 王振省; 华晶晶; 郑丽平; 董存豪; 杨建昌※

    2013-01-01

      To meet the challenge of drought in China, water-saving techniques have been developed and applied in rice (Oryza sativa L.) growing areas since the last decade of 20th century, such as the dry-cultivated technique for paddy rice and the acreages of upland rice in rained areas, which has played a positive role in stabilizing and promoting food production. Manganese (Mn) as a trace element is both essential for rice growth and the essential trace elements in the human body. However, the effect of cultivation patterns on Mn absorption and use efficiency of upland and paddy rice rarely has been reported. The objective of this study was to evaluate the difference between upland rice cultivar Zhonghan3 (japonica) and paddy rice cultivar Wuxiangjing99-8 (japonica) which were grown in the farm of the Yangzhou University under three cultivation patterns of moist cultivation (MC, control), plastic film mulching cultivation (PFMC), and bare cultivation (BC). The MC was based on conventional irrigation for high-yielding rice production, that is, keeping a water layer in the field from transplanting to regreening, alternating wet and dry soils during the other growth periods, and stopping the water supply obe week before harvest. The total quantity of irrigation was 5,213 m3 ha-1. In the PFMC treatment, the field was dry-plowed, and then, the beds (1.5 m in width) were made and mulched, the beds were fully watered from transplanting to one week after transplantation while the plants were alive. The DC treatment was the same as the PFMC treatment, except for not mulching before transplanting. Totally, water of 723 m3 ha-1 was supplied at the vigorous tillering, booting, and heading stages, and no water was irrigated during the other growth periods. From heading to maturity, the soil moisture was monitored by tensiometers that were installed in the field. The soil water potential was normally at-15 to-25 kPa. The results showed that, compared with the MC, the grain yield

  14. Is there a second fragrance gene in rice?

    NARCIS (Netherlands)

    Fitzgerald, M.A.; Hamilton, N.R.S.; Calingacion, M.N.; Verhoeven, H.A.; Butardo, V.M.

    2008-01-01

    Aromatic rice is highly prized by most rice consumers, and many countries cultivate traditional and improved aromatic varieties. 2-Acetyl-1-pyrroline (2AP) is the major aromatic compound in rice, and is believed to accumulate because of an eight-base-pair (8-bp) deletion in an allele at the fragranc

  15. 模拟栽培条件的改变对稻田主要温室气体排放的影响%Simulation of greenhouse gas emissions as affected by cultivation practices in rice fields

    Institute of Scientific and Technical Information of China (English)

    孙园园; 孙永健; 杨志远; 徐徽; 马均; 李首成

    2013-01-01

    Using the high resolution(1 m)IKONOS satellite and employing typical sampling and terrain→land use→land cover→comprehensive information extraction method,representative of the middle Jintang hilly area feature were selected .Detailed farmer investigations were carried out,including crop diversity,tillage,fertilizer,manure type,irri-gationsoil pH,meteorological data.Emissions of CO2,N2O and CH4 emissions of rice fields with farmers crop production conditions simulated using DNDC model .In-depth analysis of factors contributing to emissions of CO2,N2O,CH4,and global warming potential (GWP)was performed by changing a factor of production conditions of the winter water paddy rice field (winter paddy field area accounts for 58 .07%of the area of research)in the target area .The results show that nitrogen fertilizer,organic fertilizer number and variety types,animal dung urine into quantity,middle-stage drainage, depth of cultivated fields,average temperature,rainfall,soil pH,content of soil organic matter,soil texture have signifi-cant influence on greenhouse gas emissions in paddy field .GWP of CO2,CH4,and N2O emissions of one year from three kinds of paddy field-permanently flooded paddy fields (PF),rapeseed-paddy rice fields (RR)and winter wheat-paddy rice fields (RW)were in the order of RW>RR>PF .%利用IKONOS高分辨率(1 m)卫星遥感图,运用典型抽样和地形→土地利用→土地覆盖→综合信息提取的方法,选定了川中丘陵区代表区域,通过对研究区域农业生产情况、土样、水样和气象资料的调查和分析,利用DNDC模型模拟农户作物生产条件下稻田CO2、CH4和N2 O排放情况,在此基础上,通过改变目前的研究区域冬水田(PF)(PF占研究区域面积的58.07%)生产条件中的某一影响因子,进一步研究这一因子的改变对CO2、CH4和N2O排放的影响及全球增温潜势(GWP)变化情况。结果表明:氮肥种类和数量、有机肥种

  16. Bumper harvest of super rice in south and north China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Recently. a great progress was made in breeding and cultivation of super rice in China. The South Demonstration Acceptance Meeting of China Super Rice was held in Oct 17. 2000 in Xinchang County, Zhejiang Province. Yield monitoring group organized by the Department of Science,Technology and Education, Ministry of Agriculture, China, was consisting of famous rice research scientists, agricultural technology extension experts, and government officials. In the demonstration meeting, the group investigated the rice growth of the demonstration field of the improved integrated cultivation technology of super hybrid rice, Xieyou 9308. Four representative demonstration fields from 6.87 ha of the demonstration were harvested after the current investigation of the group.

  17. Managing flood prone ecosystem for rice production in Bihar plains

    International Nuclear Information System (INIS)

    A large area of the eastern region especially Bihar (0.5 million hectare) faces flood submergence and/or drought every year which creates an unfavorable environment for crop production. In this ecosystem only flood prone rice is grown whose cultivation is entirely different than normal rice crop. Managing the flood prone ecosystem for rice production needs to evaluate the reasons and a comprehensive appropriate technology through research efforts for better rice production under such harsh ecology. An attempt was made to develop a suitable agronomic package for rice cultivation during and after flooding in flood prone plains of Bihar. (author)

  18. Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil

    Directory of Open Access Journals (Sweden)

    Delmany Moitinho Barboza

    2012-09-01

    Full Text Available The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

  19. QTLs analysis for resistance to blast disease in US weedy rice

    Science.gov (United States)

    Understanding the genetic architecture of adaptation is of great importance in evolutionary biology. US weedy rice is well-adapted to the local conditions in US rice fields. Rice blast disease is one of the most destructive diseases of cultivated rice worldwide. However, information about resistance...

  20. Tolerance to zinc deficiency in rice correlates with zinc uptake and translocation

    NARCIS (Netherlands)

    Gao, X.; Zou, C.Q.; Zee, van der S.E.A.T.M.; Hoffland, E.

    2005-01-01

    To study variation in zinc efficiency (ZE) among current Chinese rice genotypes, a pot experiment was conducted with 15 aerobic and 8 lowland rice genotypes. Aerobic rice is currently bred by crossing lowland with upland rice genotypes, for growth in an aerobic cultivation system, which is saving wa

  1. Microbial community response to two water management systems for wetland rice production in high arsenic soils

    Science.gov (United States)

    Rice cultivation on arsenic (As) impacted soils has recently garnered considerable attention. Rice plants can accumulate As in grain, especially under the continuously flooded conditions commonly utilized in wetland-rice production. However, recent studies have indicated that rice-management system...

  2. Controle de brusone e manejo de nitrogênio em cultivo de arroz irrigado Blast control and nitrogen management in lowland rice cultivation

    Directory of Open Access Journals (Sweden)

    Nand Kumar Fageria

    2004-02-01

    Full Text Available Informações sobre práticas culturais, tais como a aplicação de N e o controle de doenças causadas por fungos, em solo de várzea do Brasil são insuficientes. O objetivo deste trabalho foi avaliar a resposta do arroz irrigado a épocas de aplicação de N e ao tratamento das sementes com fungicida no controle de brusone. Aplicaram-se 90 kg ha-1 de N da seguinte forma: todo no plantio (T1; 1/3 no plantio, 1/3 45 dias após o plantio e 1/3 na iniciação do primórdio floral (T2; 1/2 no plantio e 1/2 45 dias após o plantio (T3; 1/2 no plantio e 1/2 na iniciação do primórdio floral (T4; 2/3 no plantio e 1/3 45 dias após o plantio (T5; 2/3 no plantio e 1/3 aplicado na iniciação do primórdio floral (T6 e 1/3 no plantio e 2/3 20 dias após o plantio (T7. O fungicida pyroquilon foi aplicado nas doses de 0, 200 e 400 g de ingrediente ativo por 100 kg de sementes. A produção de grãos foi influenciada significativamente pela época de aplicação de N e pelo tratamento de fungicida. A aplicação de N influenciou significativamente a matéria seca da parte aérea e a acumulação de N nos grãos. A produção máxima de grãos foi obtida pelos tratamentos T2 e T3. O tratamento com 200 g de fungicida por 100 kg de sementes aumentou significativamente a produção de grãos, em relação à testemunha.Nitrogen timing and control of fungal diseases are cultural practices in lowland rice production. The objective of this study was to determine appropriate timing of N application and adequate rate of seed treatment with pyroquilon fungicide in lowland rice. The 90 kg ha-1 N application timing were alloted as follows: total at sowing (T1; 1/3 at sowing, 1/3 at active tillering and 1/3 at panicle initiation (T2; 1/2 at sowing and 1/2 at active tillering (T3; 1/2 at sowing and 1/2 at panicle initiation (T4; 2/3 at sowing and 1/3 at active tillering (T5; 2/3 at sowing and 1/3 at panicle initiation (T6; and 1/3 at sowing and 2/3 at the start of

  3. Preliminary Study on Geographical Distribution and Evolutionary Relationships Between Cultivated and Wild Adzuki Bean (Vigna angularis var. angularis and var. nipponensis) by AFLP Analysis

    Institute of Scientific and Technical Information of China (English)

    ZONG Xu-xiao; Duncan Vaughan; Norihiko Tomooka; Akito Kaga; WANG Xin-wang; GUAN Jian-ping; WANG Shu-min

    2003-01-01

    A set of representative 146 adzuki (Vigna angularis var. angularis, and var. nipponensis)germplasm from 6 Asian countries traditionally for adzuki bean production, together with an out group stand-ard rice bean (Vigna umbellata), were analyzed by AFLP methodology using 12 informative primer pairs.313 unambiguous polymorphic bands were created. According to the dendrogram by cluster analysis based onAFLP banding, 143 of the accessions were distinct and revealed enough genetic diversity for identification andclassification of accessions within Vigna angularis. A neighbor joining tree was generated using newly devel-oped Innan's nucleotide diversity estimate from the AFLP data. From analysis, 7 distinct evolutionary groups,named as "Chinese cultivated", "Japanese cultivated", "Japanese complex-Korean cultivated", "Chinesewild", "China Taiwan wild", "Nepal-Bhutan cultivated" and "Hymalayan wild", were detected. Nucleotidediversity with geographical distribution of each group is discussed, regarding the evolutionary relationships be-tween wild and cultivated adzuki beans. The preliminary results indicated that cultivated adzuki bean should bedomesticated from at least 4 progenitors in at least 3 geographical origins.

  4. Semi-dwarf rice varieties in the United States

    International Nuclear Information System (INIS)

    Semi-dwarf rice varieties are grown extensively in California and are beginning to be adopted in the northern United States. Their background is varied. Some derive their semi-dwarf status from Asian ancestors. Use has been made of TN-1, IR8, IR659-10-8-3 and IR1318 (containing TN1). Other semi-dwarfs in California derive their short stature from induced mutants. The principal parent is Calrose 76 derived from an induced mutation in Calrose (released in 1976). The first US semi-dwarf variety was LA 110, developed at the Rice Experiment Station at Crowley, Louisiana from a cross TN-I x M4 (from Sri Lanka) released in 1974. The next group of semidwarf varieties was developed in cooperation between the California Coop. Rice Research Foundation, The California Agricultural Experiment Station and the USDA Agric. Research Service. These are listed. Semidwarf long grain varieties were developed in Texas: Bellemont (1981) and Lemont (1983), both using IR659-10-8-3 as source of semidwarf culm. Two other long grain varieties Leah (1982) and Toro-2 (1984) released by the Rice Research Station in Crowley, Louisiana, derive their short stature form C19902, a line developed at Crowley, but still reaching a height of 89-94 cm. There are other short statured varieties in the US which are not truly semidwarfs, such as Bond and Newbonnet in Arkansas, Skybonnet and Pecos in Texas. The general trend is towards shorter varieties. Calrose 76 and M7 are being replaced. M-201 and L-202 are the shortest and have excellent lodging resistance. Their background is IR8 or TN1. Too short varieties like Bellemont may have seedling emergence problems. The area of cultivated varieties can only be estimated based upon seed production. According to such estimates, total rice area in California 1984 was 184,100 ha, of which 178,100 (ca. 97%) were under semidwarf varieties. The total rice area in the US 1984 was 1.139,000 ha, of which 249,500 ha or 21,9% were under semidwarf varieties. The rice

  5. Low-carbon and Efficient Cultivation Techniques for Potato Grown in the Rotation System of Potato-Organic Rice-Leaf Vegetable in Hilly Areas%丘陵地区马铃薯-有机稻-叶菜低碳高效栽培技术

    Institute of Scientific and Technical Information of China (English)

    王永平; 解振强; 罗先进

    2013-01-01

      马铃薯—有机稻—叶菜低碳高效栽培技术是一种将马铃薯、水稻、叶菜三类作物周年轮作的新型种植模式.2月份将马铃薯种摆放在水稻田里,覆盖稻草生产马铃薯,5月份收获马铃薯.马铃薯收获后种植早中稻,10~11月份收获水稻,保留稻草用于次年春季马铃薯种植.水稻收获后在水稻田内种植菠菜、芫荽、茼蒿等叶菜类蔬菜,叶菜在春节前后采收完毕.该方法将水旱轮作有机结合起来,既有利于稻草还田,增加土壤有机质,改善土壤生态环境,又有利于提高土地利用率,提高土地产出,为农业增效和农民增收提供一种有效途径.%The low-carbon and efficient cultivation technique of potato-rice-leaf vegetable is a new cultivation model that potato, rice and leaf vegetable are rotated annual y. Potato seeds are put on the surface of rice fields in February, covered with straw, and cropped in May. Early-mid rice is planted after potatoes harvested, the rice is cropped from October to November, and straw is kept for potato cultivation in spring of the next year. Leaf vegetables, such as spinach, coriander and crown daisy, are planted in the rice field, and the vegetables are harvested completely before or after Spring Festival. This method organical y combining wet field-dry field rotation, not only is conducive to the straw returning to field, increasing soil organic matter and getting soil environment better, but is beneficial to improving the utilization rate of land, and raising production from land. It is an effective way to increase agricultural crop and raise farmers income.

  6. Evaluation of Heavy Metals Contamination from Environment to Food Matrix by TXRF: The Case of Rice and Rice Husk

    Directory of Open Access Journals (Sweden)

    Fabjola Bilo

    2015-01-01

    Full Text Available This paper is devoted to the chemical analysis of contaminated soils of India and the rice grown in the same area. Total reflection X-ray fluorescence spectroscopy is a well-established technique for elemental chemical analysis of environmental samples, and it can be a useful tool to assess food safety. Metals uptake in rice crop grown in soils from different areas was studied. In this work soil, rice husk and rice samples were analyzed after complete solubilization of samples by microwave acid digestion. Heavy metals concentration detected in rice samples decreases in the following order: Mn > Zn > Cu > Ni > Pb > Cr. The metal content in rice husk was higher than in rice. This study suggests, for the first time, a possible role of heavy metals filter played by rice husk. The knowledge of metals sequestration capability of rice husk may promote some new management practices for rice cultivation to preserve it from pollution.

  7. Microbial community structure in the rhizosphere of rice plants

    OpenAIRE

    Björn eBreidenbach; Judith ePump; Marc Gregory Dumont

    2016-01-01

    The microbial community in the rhizosphere environment is critical for the health of land plants and the processing of soil organic matter. The objective of this study was to determine the extent to which rice plants shape the microbial community in rice field soil over the course of a growing season. Rice (Oryza sativa) was cultivated under greenhouse conditions in rice field soil from Vercelli, Italy and the microbial community in the rhizosphere of planted soil microcosms was characterized...

  8. Microbial Community Structure in the Rhizosphere of Rice Plants

    OpenAIRE

    Breidenbach, Björn; Pump, Judith; Dumont, Marc G.

    2016-01-01

    The microbial community in the rhizosphere environment is critical for the health of land plants and the processing of soil organic matter. The objective of this study was to determine the extent to which rice plants shape the microbial community in rice field soil over the course of a growing season. Rice (Oryza sativa) was cultivated under greenhouse conditions in rice field soil from Vercelli, Italy and the microbial community in the rhizosphere of planted soil microcosms was characterized...

  9. Actividad Alelopática de las Arvenses Asociadas al Cultivo de Arroz (Oryza sativa L. en el Tolima-Colombia Allelophatic Activity of Arvenses Associated with the Cultivation of Rice (Oryza sativa l. in Tolima-Colombia

    Directory of Open Access Journals (Sweden)

    Elizabeth Murillo

    2006-01-01

    Full Text Available Se recolectaron e identificaron especies de arvense de la familia Asteraceae asociadas al cultivo de arroz (Oryza sativa L. en el Tolima-Colombia, y se caracterizaron morfológica, bromatológica y farmacognósticamente. Las fracciones orgánicas de la arvense con mayor contenido de sesquiterpenlactonas se evaluó por su actividad alelopática sobre la germinación y elongación de la radícula de semillas de O. sativa, colocadas en papel filtro a concentraciones de 200, 400 y 600 ppm e incubadas durante 120 horas. El cultivo de la gramínea se encontró asociado a 12 especies invasoras que presentaron gran variabilidad en sus características morfológicas y en los índices farmacognósticos. Las fracciones clorofórmicas mostraron diferencias significativas con el extracto etanólico crudo por el efecto sobre la división celular y el crecimiento radicular de semillas de O. sativa, actividad que parece estar asociada al contenido de sesquiterpenlactonas.Asteraceae weed species associated with rice (Oryza sativa L. in the state of Tolima-Colombia were gathered, identified and morphologic, pharmacognostic and bromatologically characterized. Allelopathic activity for those organic fractions of weed with high content of sesquiterpene lactone was evaluated on the germination and radicle length of O. sativa seeds in filter paper. Both crude extract and chromatographic fractions were incubated for 120 hours at concentrations of 200, 400 and 600 ppm. Cultivation of the grainswas associated to 12 weed species which presented great variability in its morphologic characteristics and farmacognostic index. Chloroformic fractions gave significant differences with the ethanolic extract due to the effect on the cellular division and the radicle elongation of the O. sativa seeds, activity that seems to be associated to the content of sesquiterpene lactone.

  10. Azolla-Anabaena as a Biofertilizer for Rice Paddy Fields in the Po Valley, a Temperate Rice Area in Northern Italy

    Directory of Open Access Journals (Sweden)

    Stefano Bocchi

    2010-01-01

    Full Text Available Azolla is a floating pteridophyte, which contains as endosymbiont the nitrogen-fixing cyanobacterium Anabaena azollae (Nostocaceae family. Widely cultivated in the Asian regions, Azolla is either incorporated into the soil before rice transplanting or grown as a dual crop along with rice. To examine the feasibility of its use in flooded rice fields sited in the Temperate European Areas, we carried out a series of experiments in PVC tanks during 2000–2002 in Po Valley (northern Italy conditions, to study the growth-development dynamics and the resistance/tolerance to low temperatures and to commonly used herbicides of several different Azolla strains. Three out of five strains tested survived the winter, with an increase in biomass from March to May producing approximately 30–40 kg ha−1 of nitrogen. One of these strains, named “Milan”, emerged as the most resistant to herbicide and the most productive. Of the herbicides tested, Propanil permitted the survival of growing Azolla.

  11. Effect of Interplanting with Zero Tillage and Straw Manure on Rice Growth and Rice Quality

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The interplanting with zero-tillage of rice, i.e. directsowing rice 10-20 days before wheat harvesting, and remaining about 30-cm high stubble after cutting wheat or rice with no tillage, is a new cultivation technology in wheat-rice rotation system. To study the effects of interplanting with zero tillage and straw manure on rice growth and quality, an experiment was conducted in a wheat-rotation rotation system. Four treatments, i.e. ZIS (Zero-tillage, straw manure and rice interplanting), ZI (Zero-tillage, no straw manure and rice interplanting), PTS (Plowing tillage, straw manure and rice transplanting), and PT (Plowing tillage, no straw manure and rice transplanting), were used. ZIS reduced plant height, leaf area per plant and the biomass of rice plants, but the biomass accumulation of rice at the late stage was quicker than that under conventional transplanting cultivation. In the first year (2002), there was no significant difference in rice yield among the four treatments. However, rice yield decreased in interplanting with zero-tillage in the second year (2003). Compared with the transplanting treatments, the number of filled grains per panicle decreased but 1000-grain weight increased in interplanting with zero-tillage, which were the main factors resulting in higher yield. Interplanting with zero-tillage improved the milling and appearance qualities of rice. The rates of milled and head rice increased while chalky rice rate and chalkiness decreased in interplanting with zero-tillage. Zero-tillage and interplanting also affected rice nutritional and cooking qualities. In 2002, ZIS showed raised protein content, decreased amylose content, softer gel consistency, resulting in improved rice quality. In 2003, zero-tillage and interplanting decreased protein content and showed similar amylose content as compared with transplanting treatments. Moreover, protein content in PTS was obviously increased in comparison with the other three treatments. The rice in

  12. Improving Former Shifted Cultivation Land Using Wetland Cultivation in Kapuas District, Central Kalimantan

    Directory of Open Access Journals (Sweden)

    Wahyudi Wahyudi

    2013-11-01

    Full Text Available Degraded forest area in Kalimantan could be caused by shifted cultivation activity that be conducted by local peoples in the surrounding forest areas. Efforts to improve the former shifted cultivation area (non productive land is developing the settled cultivation by use of irrigation system, better paddy seed, land processing, fertilizing, spraying pesticide, weeding, and better acces to the market. Local peoples, especially in Kalimantan, has been depended their food on the shifted cultivation pattern since the long time ago. This tradition could cause forest damage, forest fire, forest degradation, deforestation, and lose out of children education because they were following shifted cultivation activity although its space is very far from their home. This research was aimed to improve former shifted cultivation lands using wetland cultivation in order to improve land productivity and to support food security in the local community. This research was administratively located in Tanjung Rendan Village, Kapuas Hulu Sub-Ddistrict, Kapuas District, Central Kalimantan Province, Indonesia. Data of rice yield from settled cultivation and shifted cultivation were got from 15 households that was taking by random at 2010 to 2011. Homogeneity test, analysis of variants, and least significant different (LSD test using SPSS 15.0 for Windows. Result of this research showed that paddy yield at settled cultivation was significantly different and better than shifted cultivation at 0.05 level. LSD test also indicated that all paddy yields from settled cultivation were significantly different compare to shifted cultivation at the 0.05 level. The community in Tanjung Rendan Villages preferred settled cultivation than shifted cultivation, especially due to higher paddy production. Profit for settled cultivation was IDR10.95 million ha-1, meanwhile profit for shifted cultivation was just IDR 2.81 million ha-1 only. Settled cultivation pattern could to improve

  13. Impacts of Climate Change on Rice Yield, Case: Nam Xong

    OpenAIRE

    Khadka, Nishan

    2016-01-01

    Most of the farmers in Lao PDR cultivate rice as the source of living. Most of the area used for rice cultivation is rainfed rice. The agriculture of a vast population in Nam Xong River Basin is dependent on monsoons where rice is grown between May and November. The most important parameters to determine the yield variation in the region is the climate and soil contrast. Nam Xong River Basin is located in the Vientiane province. It is divided into mountainous upper Nam Xong, valleys in th...

  14. Rice methylmercury exposure and mitigation: a comprehensive review

    Science.gov (United States)

    Rothenberg, Sarah E.; Windham-Myers, Lisamarie; Creswell, Joel E.

    2014-01-01

    Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice (Orzya sativa) cultivated or purchased in 15 countries. Not surprisingly, both rice total mercury and methylmercury levels were significantly higher in polluted sites compared to non-polluted sites (Wilcoxon rank sum, price percent methylmercury (of total mercury) did not differ statistically between polluted and non-polluted sites (Wilcoxon rank sum, p=0.35), suggesting comparable mercury methylation rates in paddy soil across these sites and/or similar accumulation of mercury species for these rice cultivars. Studies characterizing the effects of rice cultivation under more aerobic conditions were reviewed to determine the mitigation potential of this practice. Rice management practices utilizing alternating wetting and drying (instead of continuous flooding) caused soil methylmercury levels to spike, resulting in a strong methylmercury pulse after fields were dried and reflooded; however, it is uncertain whether this led to increased translocation of methylmercury from paddy soil to rice grain. Due to the potential health risks, it is advisable to investigate this issue further, and to develop separate water management strategies for mercury polluted and non-polluted sites, in order to minimize methylmercury exposure through rice ingestion.

  15. Rice methylmercury exposure and mitigation: a comprehensive review.

    Science.gov (United States)

    Rothenberg, Sarah E; Windham-Myers, Lisamarie; Creswell, Joel E

    2014-08-01

    Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice (Orzya sativa) cultivated or purchased in 15 countries. Not surprisingly, both rice total mercury and methylmercury levels were significantly higher in polluted sites compared to non-polluted sites (Wilcoxon rank sum, pmethylmercury (of total mercury) did not differ statistically between polluted and non-polluted sites (Wilcoxon rank sum, p=0.35), suggesting comparable mercury methylation rates in paddy soil across these sites and/or similar accumulation of mercury species for these rice cultivars. Studies characterizing the effects of rice cultivation under more aerobic conditions were reviewed to determine the mitigation potential of this practice. Rice management practices utilizing alternating wetting and drying (instead of continuous flooding) caused soil methylmercury levels to spike, resulting in a strong methylmercury pulse after fields were dried and reflooded; however, it is uncertain whether this led to increased translocation of methylmercury from paddy soil to rice grain. Due to the potential health risks, it is advisable to investigate this issue further, and to develop separate water management strategies for mercury polluted and non-polluted sites, in order to minimize methylmercury exposure through rice ingestion.

  16. The Subtelomere of Oryza sativa Chromosome 3 Short Arm as a Hot Bed of New Gene Origination in Rice

    Institute of Scientific and Technical Information of China (English)

    Chuanzhu Fan; Yong Zhang; Yeisoo Yu; Steve Rounsley; Manyuan Long; Rod A.Wing

    2008-01-01

    Despite general observations of non-random genomic distribution of new genes,it is unclear whether or not new genes preferentially occur in certain genomic regions driven by related molecular mechanisms.Using 1.5 Mb of genomic sequences from short arms of chromosome 3 of Oryza glaberrima and O.punctata,we conducted a comparative genomic analysis with the reference O.sativa ssp-japonica genome.We identified a 60-kb segment Iocated in the middle of the subtelomeric region of chromosome 3,which is unique to the species O.sativa.The region contained gene duplicares that occurred in Asian cultivated rice species that diverged from the ancestor of Asian and African cultivated rice one million years ago(MYA).For the 12 genes and one complete retrotransposon identified in this segment in O.sativa ssp.japonica,we searched for their parental genes.The high similarity between duplicated paralogs further supports the recent origination of these genes.We found that this segment was recently generated through multiple independent gene recombination and transposon insertion events.Among the 12 genes,we found that five had chimeric gene structures derived from multiple parental genes.Nine out of the 12 new genes seem to be functional,as suggested by Ka/Ks analysis and the presence of cDNA and/or MPSS data.Furthermore,for the eight transcribed genes,at least two genes could be classified as defense or stress response-related genes.Given these findings,and the fact that subtelomeres are associated with high rates of recombination and transcription,it is likely that subtelomeres may facilitate gene recombination and transposon insertions and serve as hot spots for new gene origination in rice genomes.

  17. The potential of natural enemies to suppress rice leaffolder populations.

    OpenAIRE

    Kraker, de, A Bram

    1996-01-01

    Rice leaffolders Cnaphalocrocis medinalis and Marasmia spp. (Lepidoptera: Pyralidae) are considered major pests in many Asian countries. Insecticide use against leaffolders is wide-spread, but may not be justified due to tolerance of the rice crop to leaffolder injury and a high level of natural biological control. This study was conducted to obtain more insight in the potential of indigenous natural enemies to suppress rice leaffolder populations and reduce the damage inflicted to the crop. ...

  18. Rice-Traditional Medicinal Plant in India

    Directory of Open Access Journals (Sweden)

    M. Umadevi

    2012-05-01

    Full Text Available Rice is rich in genetic diversity, with thousands of varieties grown throughout the world. Rice cultivation is the principal activity and source of income for about 100 million households in Asia and Africa. Rice has potential in a wide range of food categories. Besides having nutritional and medicinal benefits, the by-products of rice are equally important and beneficial. By-products from growing rice create many valuable and worthwhile products. The unedible parts, that are discarded through the milling process, and the edible part could be transformed into some of the following suggested products. Rice can be used to treat skin conditions. The rice is boiled, drained and allowed to cool and mashed. The rice is made into a paste or moulded into balls and these can be applied to boils, sores, swellings and skin blemishes. Other herbs are sometimes added to the rice balls to increase their medicinal effects. Sticky glutinous rice is often taken to treat stomach upsets, heart-burn and indigestion. Extracts from brown rice have been used to treat breast and stomach cancer and warts. They have also been used to treat indigestion, nausea and diarrhoea.

  19. Characteristics of Growth and Yield Formation of Rice in Rice-Fish Farming System

    Institute of Scientific and Technical Information of China (English)

    YANG Yong; ZHANG Hong-cheng; HU Xiao-jun; DAI Qi-gen; ZHANG Yong-jiang

    2006-01-01

    By using single rice cultivation as a control, the effect of rice-fish culture on growth dynamic, plant type and yield formation of rice was studied. The results showed as follows: rice-fish culture improved the physical-chemical properties of arable layer soil of paddy field, extended growth period of rice, increased dry matter and LAI of different growth stages,improved three top leaves area, deterred the degeneration of leaves function, increased the diameter of stem, promoted the growth of roots and the formation of roots in the extended stem. At the same time, rice-fish culture extended the length of basal internodes, increased the number of internodes, uplifted the gravity of plant, and depressed the root vigor. For the grain yield and yield structure of rice, rice-fish culture decreased ear/tillering ratio, spikelet/panicle and seed set percentage,increased grain weight. If variety choice and cultivation technology were controlled appropriately, rice-fish culture could increase the effective panicles and improve grain yield of rice.

  20. 泰州市姜堰区3种水稻种植方式的调查分析%Investigation and Analysis of Three Rice Cultivation Methods in Jiangyan District

    Institute of Scientific and Technical Information of China (English)

    刘晓霞; 王显; 李亚伟; 殷琴

    2014-01-01

    对姜堰区246户农户、125.38 hm2水稻不同种植方式进行了随机调查。结果显示,在高产水平上,机插秧的产量略低于抛秧,但比直播稻高31.0 kg/667 m2;在中、低产水平上,机插秧的产量略高于抛秧,比直播稻高50.0 kg/667 m2左右。机插秧的成本比抛秧、直播方式低,而净效益却比抛秧高48.2元/667 m2,比直播稻高166.8元/667 m2。表明机插是姜堰区目前3种主要种植方式的最佳选择,也是今后水稻机械化生产的方向。%According to the survey of 246 farmers, 125.38 hm2 rice with different planting methods in Jiangyan district, the authors found out, the yield of machine transplanted rice was slightly lower than that of seedling throwing rice in high yield level, but was higher than direct seeding rice by 31.0 kg/667 m2; in middle and low yield level, the yield of machine transplanted rice was slightly higher than that of seedling throwing rice, and higher than direct seeding rice by 50.0 kg/667 m 2. The cost of machine transplanted rice was the lest, but the net benefits was the highest. The results showed that machine transplanted rice is the best choice of Jiangyan district and the future direction of mechanization of rice production.

  1. 中稻高产栽培最佳施肥量、施肥技术的研究%Study of Optimum Fertilizing Amount and Fertilization Technology of High-yield Cultivation of Middle-season Rice

    Institute of Scientific and Technical Information of China (English)

    吴剑英

    2013-01-01

    [Objective] The research aimed to provide the basis for the fertilizing method of high-yield cultivation of middle-season rice.[Method] Trials of different fertilizing method,different level of nitrogenous fertilizer and different level of potash fertilizer were carried out.According to the nutrient preserving capability of the soil,law of fertilizer requirement and fertilizer response,optimum fertilizing amount and ratio of N,P2O5 and K2O and the corresponding fertilization technology were given.[Result] Based on the experimental results,the optimum fertilizing method and optimum fertilizing amount were obtained with variance analysis.[Conclusion] The optimum fertilizing method was stabilizing before and attack the middle method,whose ratio of basic fertilizer,tiller fertilizer,fertilization for head sprouting and granula fertilizer was 4∶ 3∶ 3∶ 0.The optimum fertilizing amount of N,P2O5 and K2Owas 180,75 and 120 kg/hm2,respectively.%[目的]为青阳县中稻超高产栽培提供科学施肥依据.[方法]通过对中稻开展不同施肥方法、不同氮肥水平、不同钾肥水平肥效试验,同时根据土壤供肥性能、作物需肥规律和肥料效应,提出氮磷钾适宜施用量、比例以及相应的施肥技术.[结果]根据试验结果,应用方差分析,得出最佳施肥方法和最佳施肥量.[结论]生产上推荐最佳施肥方法是稳前攻中法,即基肥∶分蘖肥∶穗肥∶粒肥为4∶3∶3∶0.最佳施肥量是纯氮(N) 180 kg/hm2、纯磷(P2O5)75 kg/hm2、纯钾(K2O) 120 kg/hm2.

  2. Advances in the understanding of inter-subspecific hybrid sterility and wide-compatibility in rice

    Institute of Scientific and Technical Information of China (English)

    OUYANG YiDan; CHEN JiongJiong; DING JiHua; ZHANG QiFa

    2009-01-01

    Hybrid sterility is a major form of postzygotic reproductive isolation and frequently occurs in hybrids between divergent populations, such as the indica and japonica subspecies of Asian cultivated rice (Oryza sativa L.). It has been a major barrier for utilization of the strong heterosis expressed in hybrids between indica and japonica. A large number of loci for rice inter-subspecific hybrid sterility have been identified by genetic analysis. Cytological studies revealed that male and female gamete abortions and reduced affinity between the uniting gametes all occurred in indica-japonica hybrids, suggesting the complexity of the causes for inter-subspecific hybrid sterility. Two genes conditioning embryo-sac and pollen sterility respectively in indica-japonica hybrids have been cloned recently, providing opportunities for molecular characterization of the indica-japonica hybrid sterility and wide-compatibility. Future studies should aim at cloning more genes for indica-japonica hybrid sterility, characterizing the underlying molecular mechanism, and utilization of the findings for the development of inter-subspecific hybrids to increase rice productivity.

  3. Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent genes.

    Science.gov (United States)

    Long, Yunming; Zhao, Lifeng; Niu, Baixiao; Su, Jing; Wu, Hao; Chen, Yuanling; Zhang, Qunyu; Guo, Jingxin; Zhuang, Chuxiong; Mei, Mantong; Xia, Jixing; Wang, Lan; Wu, Haibin; Liu, Yao-Guang

    2008-12-01

    Sterility is common in hybrids between divergent populations, such as the indica and japonica subspecies of Asian cultivated rice (Oryza sativa). Although multiple loci for plant hybrid sterility have been identified, it remains unknown how alleles of the loci interact at the molecular level. Here we show that a locus for indica-japonica hybrid male sterility, Sa, comprises two adjacent genes, SaM and SaF, encoding a small ubiquitin-like modifier E3 ligase-like protein and an F-box protein, respectively. Most indica cultivars contain a haplotype SaM(+)SaF(+), whereas all japonica cultivars have SaM(-)SaF(-) that diverged by nucleotide variations in wild rice. Male semi-sterility in this heterozygous complex locus is caused by abortion of pollen carrying SaM(-). This allele-specific gamete elimination results from a selective interaction of SaF(+) with SaM(-), a truncated protein, but not with SaM(+) because of the presence of an inhibitory domain, although SaM(+) is required for this male sterility. Lack of any one of the three alleles in recombinant plants does not produce male sterility. We propose a two-gene/three-component interaction model for this hybrid male sterility system. The findings have implications for overcoming male sterility in inter-subspecific hybrid rice breeding.

  4. REVIEW ON BANDED LEAF AND SHEATH BLIGHT OF RICE CAUSED BY Rhizoctonia solani KUHN

    Directory of Open Access Journals (Sweden)

    P. Srinivas

    2013-12-01

    Full Text Available Rice (Oryza sativa L. is a graminaceous crop. It is one of the important staple foods for Asian countries. Sheath blight disease is an important fungal disease of rice. Currently, this disease is distributed in almost all the rice growing states. The disease is alarming due to its intensive cultivation of modern high yielding varieties with high doses of nitrogenous fertilizers. Crop with a high plant density and close canopy associated favors disease build up from panicle initiation onwards. Poor weed management practices and increase in frequency of irrigation have aggravated, incidence of the disease due to modified micro climatic conditions. The disease was first recorded from Japan (Miyake, 1910. In India, the disease was first reported from Gurudaspur, Punjab (Paracer and Chahal, 1963 and later it was reported from Uttar Pradesh (Kohli, 1966. The management of this disease is possible only after the detailed study of different aspect of this disease and the pathogen. Management of the disease below its economic threshold is important for increasing the production, productivity and quality of the produce. Recognizing the importance of the problem, need for the effective and socio economically feasible management of the pathogen, the present review presented by keeping the above stated factors of the disease into consideration.

  5. Uptake of trace element by rice

    International Nuclear Information System (INIS)

    The behaviour of trace element in rice paddy field ecosystem is of great significance as rice is a staple food of India particularly in Meghalaya. In general, cultivating system is an important factor for the plant uptake of trace element from soil. Rice paddy fields have a unique ecosystem from Radioecology point of view. Rice is usually planted under flood conditions in order to provide the best environment for its growth. In the present study, rice grain samples and surface paddy soil samples were collected from the fields to obtain Transfer Factor under equilibrium condition in the field existing around Uranium mineralization zone. Obtaining local soil to rice uptake is important because it depends on climate and soil properties. The objective of the present study is to generate the transfer parameter in the paddy field ecosystem to predict the behaviour of trace elements in the paddy located in the area adjoining the uranium mines in Meghalaya. (author)

  6. Mapping Rice Production in China with AVHRR Imagery

    Science.gov (United States)

    Paliouras, Eleni J.; Emery, William

    2001-01-01

    The study of rice agriculture is necessary for both the importance of rice as a vital food source and because of the fact that cultivating it has an unfortunate byproduct, namely methane gas. As a food source, rice is a staple for a large majority of the world's population, especially in Asia. Because the populations of many Asian nations are increasing at rapid rates, the production of rice will need to similarly increase. In 1989, it was estimated that the demand for rice would increase by 65% by the year 2019. Rice crops are considered to be one of the primary anthropogenic sources of methane gas. A reason for concern is that this gas is a so-called "greenhouse" trace gas and given its increasing levels in the atmosphere, is thought to contribute to the suspected global warming phenomenon. Some estimate that methane may contribute up to 20% to the global warming effect. Trace gas emissions from anthropogenic sources is an issue that generates great worldwide interest because of the fact that mankind is very likely affecting the current and future climate in potentially negative ways. In an effort to better understand these effects, scientists and engineers are conducting research on all of the varied fronts which relate to climate change and biosphere/atmosphere interactions. The study of global warming through increasing concentrations of greenhouse gases is one area which has received much media and scientific attention. Research fueled by debates on this topic is being conducted on numerous, interrelated fronts in an effort to better understand the complex relationship between human activities and the earth's climate. The research ranges from attempting to verify if the observed data even supports the existence of an anthropogenically generated global-warming phenomenon, to identification of sources and sinks of the trace gases, to measuring the source strengths, to studies which focus on modeling the processes which generate the gases, and finally, to trying

  7. Plant growth and cultivation.

    Science.gov (United States)

    Podar, Dorina

    2013-01-01

    There is a variety of methods used for growing plants indoor for laboratory research. In most cases plant research requires germination and growth of plants. Often, people have adapted plant cultivation protocols to the conditions and materials at hand in their own laboratory and growth facilities. Here I will provide a guide for growing some of the most frequently used plant species for research, i.e., Arabidopsis thaliana, barley (Hordeum vulgare) and rice (Oryza sativa). However, the methods presented can be used for other plant species as well, especially if they are related to the above-mentioned species. The presented methods include growing plants in soil, hydroponics, and in vitro on plates. This guide is intended as a starting point for those who are just beginning to work on any of the above-mentioned plant species. Methods presented are to be taken as suggestive and modification can be made according to the conditions existing in the host laboratory. PMID:23073874

  8. Resposta e níveis críticos de potássio para o arroz cultivado em solos de várzea inundados Response and critical levels of potassium for rice cultivated in lowland waterlogged soils

    Directory of Open Access Journals (Sweden)

    Andrei Rodrigo Cabbau

    2004-02-01

    ,0, 8,1, 7,8 e 4,4% para os solos RU, GX, GM e OY, respectivamente. Da mesma forma, os níveis críticos foliares de K foram 9,6, 11,1, 10,2 e 11,5 g kg-1.The present work was conducted in a greenhouse at the Department of Soil Science of the Federal University of Lavras, Minas Gerais State, Brazil, in the period of February to June 2002, to investigate the response to potassium fertilization by rice plants (Oriza sativa L. cv. Jequitibá cultivated in flooded soils, the contribution of the K form on their nutrition, and to estimate the critic levels of the nutrient in the soils and in the plants. The experimental design utilized was the totally randomized, in the 4 x 5 factorial scheme, with four replications. Four flooded soils (Mesic Organosoil - OY, Melanic Gleysoil - GM, Haplic Gleysoil - GX, and Fluvic Neosoil - RU and five levels of potassium saturation of the potential CEC (natural content, 4, 6, 8 and 10% of the pH - 7.0 CEC saturated with K were used. Natural soil K saturations (percentage of pH-7.0 CEC were 1.55 for the OY soil, 1.30 for the GM soil, 1.65 for the GX soil, and 1.49 for the RU soil. Initially, sufficient samples of 4 dm³ for all soils received limestone to elevate the V to 50% and were incubated for 30 days. Following that, samples of 3 dm³ received the potassium treatments and a basic fertilization with macro and micronutrients and were incubated for more 30 days, in vases with capacity for 5 dm³. In the end of this period, the soils were flooded, to receive two rice plants per vase, on which were measured the leaf content of potassium at the flowering period and the yield at the end of the cycle. In sub-samples obtained from the soils of the vases before and after cultivation, the forms of potassium total K (Ktot, nonexchangeable K (Kne, exchangeable K (Ke, K in solution (Ksol and available K by the Mehlich-1 extractant were measured. From the results, it was verified that the plants responded in grain yield to the potassium fertilization

  9. Planting Performance and High-yielding Cultivation Techniques of Hybrid Rice Combination Liangyouhang 2 in Jianyang County%优质杂交稻两优航2号在建阳种植表现及高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    蔡金龙

    2012-01-01

    Liangyouhang 2,a two-line hybrid rice combination,was developed from the cross of a two-line male sterile SE21S and the restorer line Hang 2 by Rice Research Institute,Fujian Academy of Agricultural Sciences,and it was certified and released for commercial production in 2008 in Fujian province.In 2010,Liangyouhang 2 was introduced and planted in Jianyang County of Fujian province for high yield and rice quality.In this paper,we introduced planting performance and high-yielding cultivation techniques of Liangyouhang 2.%两优航2号是福建省农科院水稻所用两系不育系SE21S与恢复系航2号配组而成的两系杂交稻新品种,2008年通过福建省农作物品种审定。2010年建阳市引进试种,表现米质优、产量高。介绍了两优航2号在建阳市种植表现及高产栽培技术。

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

    Science.gov (United States)

    Tran Ba, Linh; Sleutel, Steven; Nguyen Van, Qui; Thi, Guong Vo; Le Van, Khoa; Cornelis, Wim

    2016-04-01

    Soil quality of shallow paddy soils may be improved by introducing upland crops and thus a more diverse crop cultivation pattern. Yet, the causal relationship between crop performance and enhanced soil traits in rice-upland crop rotations remains elusive. The objectives of this study were to (i) find correlations among soil properties under different rice-upland crop systems and link selected soil properties to rice growth and yield, (ii) present appropriate values of soil parameters for sustainable rice productivity in heavy clay soil, (iii) evaluate the effect of rotating rice with upland crops on rice yield and economic benefit in a long-term experiment. A rice-upland crop rotational field experiment in the Vietnamese Mekong delta was conducted for 10 years using a randomized complete block design with four treatments and four replications. Treatments were: (i) rice-rice-rice (control - conventional system as farmers' practice), (ii) rice-maize-rice, (iii) rice-mung bean-rice, and (iv) rice-mung bean-maize. Soil and plant sampling were performed after harvest of the rice crop at the end of the final winter-spring cropping season (i.e. year 10). Results show differences in rice growth and yield, and economic benefit as an effect of the crop rotation system. These differences were linked with changes in bulk density, soil porosity, soil aggregate stability index, soil penetration resistance, soil macro-porosity, soil organic carbon, acid hydrolysable soil C and soil nutrient elements, especially at soil depth of 20-30 cm. This is evidenced by the strong correlation (P < 0.01) between rice plant parameters, rice yield and soil properties such as bulk density, porosity, penetration resistance, soil organic carbon and Chydrolysable. It turned out that good rice root growth and rice yield corresponded to bulk density values lower than 1.3 Mg m-3, soil porosity higher than 50%, penetration resistance below 1.0 MPa, and soil organic carbon above 25 g kg-1. The optimal

  11. Moulds and mycotoxins in rice in Swedish retail

    OpenAIRE

    Fredlund, Elisabeth; Thim, Anna Maria; Gidlund, Ann; Brostedt, Siv; Nyberg, Marianne; Olsen, Monica

    2009-01-01

    Abstract A survey of moulds and mycotoxins was performed in 99 rice samples taken from Swedish retail. The main objective was to study mould and mycotoxin content in basmati rice and rice with high content in fibre. Samples of jasmine rice as well as long-grain rice were also included. The samples were analysed for the content of ochratoxin A (HPLC), aflatoxin B1, B2, G1, and G2 (HPLC, RIDAQUICK), and mould (traditional cultivation methods in combination with morphological ...

  12. Rice agroecosystem and the maintenance of biodiversity

    International Nuclear Information System (INIS)

    Rice fields are a special type of wetland. They are shallow, constantly disturbed and experience extremes in temperature and dissolved oxygen content. They receive nutrients in the form of fertilizers during rice cultivation. Rice fields; support a variety of flora and fauna that have adapted and adjusted themselves to the extreme conditions. Since rice fields also support populations of wild fish, rice?fish integration should be done in order to optimize land use and provide supplementary income to farmers. Rice?fish farming encourages farmers to judiciously apply pesticides and herbicides in their fields thus helping to control excessive and unwarranted use of these chemicals. Rice fields also support many migratory and nonmigratory bird species and provides habitat for small mammals. Thus the rice agroecosystem helps to maintain aquatic biodiversity. The Muda rice agroecosystem consists of a troika of interconnected ecosystems. The troika consisting of reservoirs, the connecting network of canals and the rice fields; should be investigated further. This data is needed for informed decision-making concerning development and management of the system so that productivity and biodiversity can be maintained and sustained. (Author)

  13. Aerobic rice mechanization: techniques for crop establishment

    Science.gov (United States)

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

    2015-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Seonghee Lee

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

  15. Can transgenic rice cause ecological risks through transgene escape?

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Alien transgene escape from genetically engineered rice to non-transgenic varieties or close wild relatives (including weedy rice) may lead to unpredictable ecological risks. However, for transgene escape to occur three conditions need to be met: (i) spatially, transgenic rice and its non-transgenic counterparts or wild relatives should have sympatric distributions; (ii) temporally, the flowering time of transgenic rice and the non-transgenic varieties or wild relatives should overlap; and (iii) biologically, transgenic rice and its wild relative species should have such a sufficiently close relationship that their interspecific hybrids can have normal generative reproduction. This paper presents research data on the geographic distribution, flowering habits, interspecific hybridization, and gene flow of cultivated rice (Oryza sativa) and its closely related wild relatives containing the AA genome. The objective is to estimate the possibility of transgene escape to non-transgenic rice varieties and wild relatives of rice, which may result in unpredictable ecological risks.

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

    Directory of Open Access Journals (Sweden)

    Yongqiang Han

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

  17. Screening of Exist Genetically Modified Elements in Local and Commercial Rice Available in Baghdad Markets Using PCR and Real-time PCR

    OpenAIRE

    Hayba Q. Younan

    2013-01-01

    Rice is one of the staple foods of the Iraqi population; therefore large amounts of rice cultivated and imported in Iraq. Because of increasing the production of GM crops especially rice crop, it was necessary to investigate if there is any genetically modified rice (GM rice) in Baghdad markets. Conventional PCR and Real-Time PCR used to create this investigation. Genomic DNA extracted from 7 samples of rice seeds that cultivated in Iraq; 31 samples of commercial rice seeds and 4 samples of k...

  18. Resilience and adaptability of rice terrace social-ecological systems: a case study of a local community's perception in Banaue, Philippines

    Directory of Open Access Journals (Sweden)

    Adam C. Castonguay

    2016-06-01

    Full Text Available The social-ecological systems of rice terraces across Southeast Asia are the result of centuries of long-term interactions between human communities and their surrounding ecosystems. Processes and structures in these systems have evolved to provide a diversity of ecosystem services and benefits to human societies. However, as Southeast Asian countries experience rapid economic growth and related land-use changes, the remaining extensive rice cultivation systems are increasingly under pressure. We investigated the long-term development of ecosystem services and the adaptive capacity of the social-ecological system of rice terrace landscapes using a case study of Banaue (Ifugao Province, Northern-Luzon, Philippines. A set of indicators was used to describe and assess changes in the social-ecological state of the study system. The resilience of the rice terraces and the human communities that maintain them was examined by comparing the current state of the system with results from the literature. Our findings indicate that, although the social-ecological system has not yet shifted to an alternative state, pressures are increasing and some cultural ecosystem services have already been lost.

  19. Effects of cultivation patterns on rice yield and soil properties in cold waterlogged paddy fields%耕作模式对冷浸田水稻产量和土壤特性的影响

    Institute of Scientific and Technical Information of China (English)

    王思潮; 曹凑贵; 李成芳; 熊又升; 汪金平

    2014-01-01

    为探明不同耕作模式对冷浸田的影响机制,挖掘冷浸田的生产潜力,以冷浸田为研究对象,通过田间试验,以常规平作模式为对照,研究了垄作和稻鱼共作模式对冷浸田水稻产量以及土壤团聚体、温度、pH及有机质和还原性物质含量以及酶活性的影响。结果表明:相比对照(CK),垄作模式(T1)能显著降低土壤微团聚体(1 mm) and organic matter content increased respectively by 67.6%and 28.0%at rice maturity stage. Treatment T2 had less effect on soil physical and chemical properties in cold waterlogged paddy fields. However, it significantly increased soil available nutrients (mainly available potassium and phosphorus) contents. Soil available potassium content increased 18.2% and 69.2% at booting and mature stages, compared with CK. It provided good soil environment and nutrition for rice growth, promoted rice growth and development, and improved rice yield. Further analysis showed that treatments T1 and T2 significantly improved rice yield in cold waterlogged paddy fields and increased yield in the range of 8.8%-25.8%. The effect of T1 on increasing rice production was the most significant, with actual output reaching 7 623 kg·hm-2. In conclusion, treatment T1 effectively improved soil properties in cold waterlogged paddy fields and increased rice yield. The effect of increasing production of treatment T2 was mainly drived by increased water and soil available nutrients in cold paddy waterlogged fields.

  20. Monitoring and Management of Imidazolinone-Resistant Red Rice (Oryza sativa L., var. sylvatica) in Clearfield® Italian Paddy Rice

    OpenAIRE

    Laura Scarabel; Cesare Cenghialta; Dario Manuello; Maurizio Sattin

    2012-01-01

    The introduction in Italy of Clearfield® rice cultivars carrying imidazolinone-resistant traits provides an efficient option to control red rice, a conspecific weed of cultivated rice. However, despite the promulgation of specific guidelines for Clearfield® technology management, imazamox red rice survivors have been reported by farmers. Forty-two fields were monitored in 2010 and 2011 throughout the Piedmont and Lombardy regions and field cases were recorded of herbicides use and agronomic p...

  1. Cutaneous Mycoses among Rice Farmers in Anambra State, Nigeria

    OpenAIRE

    Chito Clare Ekwealor; Christie Amechi Oyeka

    2013-01-01

    Rice grain is one of the world's most important food crops, and its cultivation is a major occupation in Anambra State, Nigeria. These rice farmers are exposed to various agents that predispose them to cutaneous mycoses. The aim of this work was to screen rice farmers for lesions suggestive of cutaneous mycoses and to isolate and identify fungal agents associated with the infection. This survey was carried out between November 2009 and June 2011 in Anambra State, Nigeria. Clinical samples col...

  2. The System of Rice Intensification: Time for an empirical turn

    OpenAIRE

    Glover, D.

    2011-01-01

    The System of Rice Intensification (SRI) is claimed to be a new, more productive and more sustainable method for cultivating rice. These claims have proved controversial. One dimension of the controversy has centred on the imprecision with which SRI's component practices have been defined. The supporters of SRI suggest that the system has been designed to satisfy the needs of rice itself, implying that it is a set of integrated, mutually reinforcing practices that need to be implemented as a ...

  3. Factors Affecting Methane Emission from Rice Paddies

    Institute of Scientific and Technical Information of China (English)

    于心科; 王卫东; 等

    1995-01-01

    A comparative study of rice paddies and the uncovered water field in Taoyuan(Hunan) showed that methane emission from rice-vegetated paddy fields in 1993 was different from that in 1992(I,e,lower in rates and irregular in pattern).Climate has obvious influence on methane emission .And ebullition made a considerable contribution to the total flux of methane emission from rice paddies (45%).This implies that the intensification of paddy cultivation of rice might not be,as was proposed,the main con-tributor to the observed gradual increasing of atmospheric methane.24-hour automatic measurements of atmospheric temperature,air temperature and methane concentration in the static sampling boxes revealed that temperature,in addition to fertilization and irrigation style,is one of the most important factors that control the emission of methane from rice paddies.

  4. Population structure and diversity of the aa genome of rice based on simple sequence repeats variation in organelle genome

    International Nuclear Information System (INIS)

    Maternally inherited mitochondrial and chloroplast genomes based Simple Sequence Repeat (SSR) variations were examined for their contribution to diversity of rice genome. Population structure and diversity analysis based on mitochondria and chloroplast inherited genome has been studied less as compared to nuclear genome inheritance. The present study was designed to evaluate the population structure and diversity of rice grown in Pakistan along with other countries based on maternally inherited mitochondria and chloroplast genome. The mitochondrial and chloroplast genomes were analyzed by using 42 mitochondrial and 20 chloroplast pairs of SSR primers. A slightly higher percentage of polymorphism was observed in chloroplast (30 percentage) than mitochondria (28.57 percentage). The average gene diversity for both mitochondrial and chloroplast was 0.32 oscillating from 0.041 to 0.620. The Polymorphism Information Content (PIC) value ranged from 0.040 to 0.543 with an average of 0.282, while the allelic richness ranged from two to four alleles with an average of 2.779 alleles. Mononucleotide repeats stood first (50 percentage polymorphic) for detecting polymorphism for organelle genomes followed by tri- (25 percentage), tetra- (14.29 percentage) and dinucleotide (12.5 percentage), respectively. Cluster and population structure analysis revealed two groups of accessions. On the basis of our results the AA genome of Asian cultivated rice diverges from the same origin during evolution. (author)

  5. The competitiveness of domestic rice production in East Africa: A domestic resource cost approach in Uganda

    Directory of Open Access Journals (Sweden)

    Masao Kikuchi

    2016-03-01

    Full Text Available The rapid increase of rice imports in sub-Saharan Africa under the unstable situation in the world rice market during the 2000s has made it an important policy target for the countries in the region to increase self-sufficiency in rice in order to enhance food security. Whether domestic rice production can be competitive with imported rice is a serious question in East African countries that lie close, just across the Arabian Sea, to major rice exporting countries in South Asia. This study investigates the international competitiveness of domestic rice production in Uganda in terms of the domestic resource cost ratio. The results show that rainfed rice cultivation, which accounts for 95% of domestic rice production, does not have a comparative advantage with respect to rice imported from Pakistan, the largest supplier of imported rice to Uganda. However, the degree of non-competitiveness is not serious, and a high possibility exists for Uganda’s rainfed rice cultivation to become internationally competitive by improving yield levels by applying more modern inputs and enhancing labour productivity. Irrigated rice cultivation, though very limited in area, is competitive even under the present input-output structure when the cost of irrigation infrastructure is treated as a sunk cost. If the cost of installing irrigation infrastructure and its operation and maintenance is taken into account, the types of irrigation development that are economically feasible are not large-scale irrigation projects, but are small- and microscale projects for lowland rice cultivation and rain-water harvesting for upland rice cultivation.

  6. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice.

    Science.gov (United States)

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E; Qiang, Sheng

    2015-05-27

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China.

  7. 建瓯市豆-繁殖-玉米新高效轮作生产栽培技术%High-efficiency Rotation Production Cultivation Techniques for Common Bean-rice Seed Multiplication-autumn Corn at Jian,ou City

    Institute of Scientific and Technical Information of China (English)

    周秀生

    2015-01-01

    Farming system of common bean-rice seed multiplication-autumn corn is an innovated high-efficiency rotation production mode for Shuiyuan town of Jian,ou city due to its unique microclimate and specific production requirement. The rotation cultivation techniques of this mode were briefly introduced according to productive practice.%四季豆—繁殖—玉米是依据建瓯市水源乡独特小气候和特殊的生产要求而创新的一种高效轮作生产方式。从生产实践方面简要介绍了这种栽培轮作技术。

  8. RICE CULTIVATION IN AN EBBTIDE SYSTEM IN THE MARANHÃO LOWLANDS, SOUTHEASTERN PERIPHERY OF AMAZONIA A CULTURA DO ARROZ EM SISTEMA DE VAZANTE NA BAIXADA MARANHENSE, PERIFERIA DO SUDESTE DA AMAZÔNIA

    Directory of Open Access Journals (Sweden)

    Marcelino Silva Farias Filho

    2009-03-01

    Full Text Available

    Agricultural production in the Maranhão State, southeastern periphery of Amazonia, Brazil, is predominantly smallholder-based and uses slash-and-burn technology. Nevertheless, other environmentally less aggressive land use systems are also relevant for food production, especially the so-called ebbtide system, in the Maranhão lowlands. This paper describes and evaluates ebbtide production, within the landless settlement project “Diamante Negro/Jutaí”, located in Monção and Igarapé do Meio, municipalities of the Maranhão lowlands. Our farmer-based assessment consisted of interviews with 14 farmers and in loco observations. Furthermore, an agroecological assessment was conducted, based on participative field experimentation, with 15 local farmers. The main factors causing rice productivity losses are related to hydric stress situations and rodents (Arvicola sapidus. The productivity and milling yield of improved rice varieties did not differ statistically.

     

    KEY-WORDS: Rice; Maranhão lowlands; smallholder agriculture; ebbtide production.

  1. Miracle Rice

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A pioneering agricultural scientist helps China find its way out of a food deficit BIG YIELDS: Despite the remarkable accomplishments he has already achieved, Yuan Longping is still working hard to improve the hybrid rice strain he has developed

  2. Effect of acetic acid on rice seeds coated with rice husk ash

    OpenAIRE

    2013-01-01

    Flooded rice cultivation promotes anaerobic conditions, favoring the formation of short chain organic acids such as acetic acid, which may be toxic to the crop. The objective of this study was to evaluate the effect of acetic acid on rice seeds coated with rice husk ash. The experiment was arranged in a 2 x 5 x 5 factorial randomized design, with two cultivars (IRGA 424 and BRS Querência), five doses of coating material (0, 2, 3,4 e 5 g kg-1 seed) and five concentrations of acetic acid (0, 3,...

  3. Obesity and Asian Americans

    Science.gov (United States)

    ... and Data > Minority Population Profiles > Asian American > Obesity Obesity and Asian Americans Non-Hispanic whites are 60% ... youthonline . [Accessed 05/25/2016] HEALTH IMPACT OF OBESITY More than 80 percent of people with type ...

  4. Water Management Practices Affect Arsenic and Cadmium Accumulation in Rice Grains

    Directory of Open Access Journals (Sweden)

    Liming Sun

    2014-01-01

    Full Text Available Cadmium (Cd and arsenic (As accumulation in rice grains is a great threat to its productivity, grain quality, and thus human health. Pot and field studies were carried out to unravel the effect of different water management practices (aerobic, aerobic-flooded, and flooded on Cd and As accumulation in rice grains of two different varieties. In pot experiment, Cd or As was also added into the soil as treatment. Pots without Cd or As addition were maintained as control. Results indicated that water management practices significantly influenced the Cd and As concentration in rice grains and aerobic cultivation of rice furnished less As concentration in its grains. Nonetheless, Cd concentration in this treatment was higher than the grains of flooded rice. Likewise, in field study, aerobic and flooded rice cultivation recorded higher Cd and As concentration, respectively. However, growing of rice in aerobic-flooded conditions decreased the Cd concentration by 9.38 times on average basis as compared to aerobic rice. Furthermore, this treatment showed 28% less As concentration than that recorded in flooded rice cultivation. The results suggested that aerobic-flooded cultivation may be a promising strategy to reduce the Cd and As accumulations in rice grains simultaneously.

  5. Responses of Antioxidant System to Cold Water Stress in Weedy and Cultivated Rice with Different Chilling Sensitivity%不同耐冷性杂草稻和栽培稻抗氧化系统对冷水胁迫的响应

    Institute of Scientific and Technical Information of China (English)

    王国骄; 王嘉宇; 马殿荣; 苗微; 赵明辉; 陈温福

    2015-01-01

    ,CAT和GR活性极显著升高;WR03-45和丽江新团黑谷剑叶的抗氧化剂(AsA和GSH)含量及AsA/DHA值和GSH/GSSG值在冷水胁迫下显著高于对照;WR03-45和丽江新团黑谷剑叶产生速率、H2O2含量和MDA含量与对照相比无显著差异。【结论】冷水胁迫下,耐冷性强的水稻通过提高抗氧化酶活性和抗氧化剂含量,减少ROS的积累以及膜脂过氧化,增强对冷水胁迫的耐性。水稻的耐冷性与胁迫下抗氧化系统清除ROS的能力有关,杂草稻WR03-45作为一种强耐冷性的种质资源可以用于栽培稻耐冷性的遗传改良。%[Objective] Rice is most sensitive to temperature from booting stage to heading and flowering stages, so cold damage during this stages severely limited rice growth and the further expansion of acreage in Northeast China. Study on the physiological mechanism of rice cold tolerance will provide an important safeguard for the rice production in Northeast China. The aim of this study was to understand the changes of reactive oxygen species metabolism, antioxidant enzyme activities and antioxidants contents in flag leaves of weedy and cultivated rice with different chilling sensitivity at flowing stage under cold water stress, and provide a theoretical basis for the breeding and cultivation of rice tolerance to cold. [Method] Two chilling-tolerant genotypes, weedy rice WR03-45 and cultivated rice Lijiangxintuanheigu, and two chilling-sensitive genotypes, weedy rice WR03-26 and cultivated rice Xiuzinuo, were used and grown in plastic pots. The time of booting stage of main spike was calculated according to length of the flag leaf collar. The tested materials were subjected to low temperature in cold water pool at booting stage, and the control was the tested materials without cold water treatment. In order to study the effects of cold water stress on reactive oxygen species (ROS) metabolism, antioxidant enzyme activities and antioxidants contents of

  6. Aroma chemistry of African Oryza glaberrima and Oryza sativa rice and their interspecific hybrids

    NARCIS (Netherlands)

    Cho, S.; Nuijten, H.A.C.P.; Shewfelt, R.L.; Kays, S.J.

    2014-01-01

    BackgroundTo increase rice production in Africa, considerable research has focused on creating interspecific hybrids between African (Oryza glaberrima Steud.) and Asian (O. sativa L.) rice in an attempt to obtain the positive attributes of each in new cultivars. Since flavor is a key criterion in co

  7. Life cycle GHG analysis of rice straw bio-DME production and application in Thailand

    International Nuclear Information System (INIS)

    Highlights: • Life cycle GHG emissions of rice straw bio-DME production in Thailand are assessed. • Bio-DME replaces diesel in engines and supplements LPG for household application. • Rice straw bio-DME in both cases of substitution helps reduce GHG emissions. - Abstract: Thailand is one of the leading countries in rice production and export; an abundance of rice straw, therefore, is left in the field nowadays and is commonly burnt to facilitate quick planting of the next crop. The study assesses the life cycle greenhouse gas (GHG) emissions of using rice straw for bio-DME production in Thailand. The analysis is divided into two scenarios of rice straw bio-DME utilization i.e. used as automotive fuel for diesel engines and used as LPG supplement for household application. The results reveal that that utilization of rice straw for bio-DME in the two scenarios could help reduce GHG emissions by around 14–70% and 2–66%, respectively as compared to the diesel fuel and LPG substituted. In case rice straw is considered as a by-product of rice cultivation, the cultivation of rice straw will be the major source of GHG emission contributing around 50% of the total GHG emissions of rice straw bio-DME production. Several factors that can affect the GHG performance of rice straw bio-DME production are discussed along with measures to enhance GHG performance of rice straw bio-DME production and utilization

  8. Weed-Suppressing Effect and Mechanism of Allelopathic Rice Accessions

    Institute of Scientific and Technical Information of China (English)

    HU Fei; KONG Chui-hua; XU Xiao-hua; ZHANG Chao-xian; CHEN Xiong-hui

    2004-01-01

    Two allelopathic rice accessions, PI312777 and Allelopathyl, significantly suppressedthe growth of associated weeds in the field. Moreover, their weed-suppressing effectswere correlated with the cultivation patterns. The weed-suppressing effects of throwingand transplanting were more effective than that of direct seeding. Furthermore, theamounts of allelochemicals (resorcinols, flavones and hydroxamic acids) produced andreleased from two allelopathic rice accessions were much higher than that from a non-allelopathic rice variety Hua-Jing-Xian 1, and reached the maximum concentration at the6th leaf stage. Differences in the weed-suppressing effects of rice accessions appear toresult from the accessions producing and releasing different amounts of allelochemicalsin the field. Further research confirmed that in PI312777 plants, allelochemicals weresynthesized by the above-ground parts, and then secreted through the root tissues. Roottissues of PI312777 plants never produced the allelochemicals. Root exudates fromPI312777 could significantly inhibit the growth of E. crus-galli surrounding rice plantsin water culture. However, when activated carbon was added to the culture solution, whichcould absorb allelochemicals from root exudates, the growth of E. crus-galli was nolonger significantly inhibited. Weed-suppressing effects of rice accessions depended onallelopathy, cultivation patterns and other factors in rice fields, while allelopathywas one of important factors. Interestingly, the amounts of allelochemicals produced andreleased from allelopathic rice plants may be induced by the presence of E. crus-galli.This suggests that there is a possible chemical recognition between rice and E. crus-galli.

  9. Effect of System of Rice Intensification on Grain Plumpness in Association with Source-Sink Ratio in Mid-Season Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiong-hui; XU Fu-xian; WAN Bang-hui; XIONG Hong; PENG Hai-feng; ZHU Yong-chuan; LU Yan-peng; WANG Gui-xiong; LIANG Ke-qin; ZHAO Jing

    2004-01-01

    Grain plumpness under two cultivation methods, the system of rice intensification(SRI) and traditional cultivation, was examined using 18 mid-season hybrid rice combinations. There existed a highly significant negative correlation between the differences of grain plumpness under the two cultivation methods and number of spikelets per panicle. The small- or middle-panicle type hybrid rice though they showed a significant decrease in leaf-grain ratio under SRI maintained normal grain filling due to plenty of source supply,while the large-panicle hybrid rice was on the contrary. It suggested that the number of spikelets per panicle below 173 under traditional cultivation, was an index for selecting variety in application of SRI in the southern region of Sichuan Province, China.

  10. Physicochemical and antioxidative properties of black, brown and red rice varieties of northern Thailand

    Directory of Open Access Journals (Sweden)

    Noppawat Pengkumsri

    2015-06-01

    Full Text Available Rice, the seed of Oryza species, is the major cereal crop in most of the developing countries. Nearly 95% of global rice production is done in Asian countries, and about half of the world’s population consumes it. Some speciality rices are not commonly consumed. Colored rice is one of such variety. In these varieties, high amounts of anthocyanin pigment are deposited in the rice coat to form its black (also known as purple, brown and red colors. Minimum studies are there to explain the properties of these rice varieties of Thailand. Thus, the current study was aimed to assess the physicochemical and antioxidative properties of three rice varieties (Chiang Mai Black rice, Mali Red rice and Suphanburi-1 Brown rice of different cultivars of northern Thailand. Rice bran extracts of these three cultivars were prepared with different solvents (polar and non-polar for the evaluation of total phytochemical content and anti-oxidant free-radical-scavenging properties. Chiang Mai Black rice contained higher concentration of phenolic acid, flavonoids, and anthocyanins (Cyanidin 3-glucoside, peonidin 3-glucoside, cyanidin chloride. Chiang Mai Black rice is richer in free-radical-scavenging compounds and activities than the other tested varieties. Polar extractions of rice bran are high in anti-oxidative compounds and activities than non-polar extractions.

  11. Analysis of the Economic Potential for a Mercosur Rice Futures Market

    Directory of Open Access Journals (Sweden)

    Waldemar Antonio da Rocha de Souza

    2015-08-01

    Full Text Available World rice production reached 488.4 thousand tons, in 2012. Asian countries are the world’s largest rice producers, followed by Latinamerica, particularly Brazil, where rice is a basic food item. In spite of the clear economic benefits bestowed by commodity futures markets, neither Asia nor Mercosur have implemented a regional rice futures market. In sum, we propose to investigate the feasibility of a Brazilian rice futures contract to serve the Mercosur region by estimating Mercosur rice price dynamics and analyze basis risk and hedging effectiveness for rice market agents in the region, in a simulation framework using a hypothetical regional contract price. Sample data and period was non-probabilistic, for accessibility and convenience. Mercosur rice price dynamics expressed Argentina and Uruguay rice prices moving in synchrony. Brazil rice prices were on lower levels. Also, all three pairs of rice price series are cointegrated, with one cointegrating equation. Again, results can be largely attributed to the different price data used, in Brazil was rough rice, while in Uruguay and Argentina milled white rice with 5%. Despite that, there are preliminary evidences that a Mercosur rice futures market could be feasible.

  12. Moulds and mycotoxins in rice from the Swedish retail market.

    Science.gov (United States)

    Fredlund, E; Thim, A-M; Gidlund, A; Brostedt, S; Nyberg, M; Olsen, M

    2009-04-01

    A survey of moulds and mycotoxins was performed on 99 rice samples taken from the Swedish retail market. The main objective was to study the mould and mycotoxin content in basmati rice and rice with a high content of fibre. Samples of jasmine rice as well as long-grain rice were also included. The samples were analysed for their content of ochratoxin A (high-performance liquid chromatography (HPLC)), aflatoxin B(1), B(2), G(1), and G(2) (HPLC, RIDA(R)QUICK), and mould (traditional cultivation methods in combination with morphological analysis). The majority of samples were sampled according to European Commission Regulation 401/2006. Subsamples were pooled and mixed before milling and both mould and mycotoxin analyses were performed on milled rice. The results showed that the majority of basmati rice (71%) and many jasmine rice samples (20%) contained detectable levels of aflatoxin B(1) (level of quantification = 0.1 microg aflatoxin kg(-1) rice). Two samples of jasmine rice and ten basmati rice samples contained levels over the regulated European maximum limits of 2 microg kg(-1) for aflatoxin B(1) or 4 microg kg(-1) for total aflatoxins. Aspergillus was the most common mould genus isolated, but also Penicillium, Eurotium, Wallemia, Cladosporium, Epicoccum, Alternaria, and Trichotecium were found. The presence of Aspergillus flavus in 21% of the samples indicates that incorrect management of rice during production and storage implies a risk of mould growth and subsequent production of aflatoxin. Rough estimates showed that high rice consumers may have an intake of 2-3 ng aflatoxin kg(-1) bodyweight and day(-1) from rice alone. This survey shows that aflatoxin is a common contaminant in rice imported to Europe.

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

    Science.gov (United States)

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

    2014-11-01

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

  14. Aerobic Rice: Benefits without going to the Gym?

    OpenAIRE

    Bayot, Ruvicyn; Templeton, Deborah J.

    2009-01-01

    Rice, a staple food for over 70% of Asians, is also the single biggest user of water, requiring 2‐3 times more water per unit of grain produced than crops such as wheat and maize. With growing populations, increased urbanisation and environmental degradation, the supply of fresh water is depleting. Recognising the water constraints to rice yield, the aim of the project entitled ‘Developing a System of Temperate and Tropical Aerobic Rice (STAR) in Asia’ was to develop water‐efficient aerobic r...

  15. 栽培模式对水稻镉积累差异及其与光合生理关系的研究%Relationships Between Cadmium Uptake Characteristics and Photosynthetic Physiology Under Different Cul-tivation Modes of Rice

    Institute of Scientific and Technical Information of China (English)

    刘洋; 张玉烛; 方宝华; 陈恺林; 李超; 何洋

    2014-01-01

    Relationships between cadmium uptake characteristics and photosynthetic physiology of rice were studied by using Xiangzaoxian 45 and Luliangyou 996 as materials under four cultivation modes:conventional water raised seedling(T1), nursery seedling(T2), dryland raised seedling(T3), direct seeding(T4). The results showed that different cultivation modes had significant effect on the yield of two culti-vars. The cadmium content of different organs followed the sequence of root>stem>leaf>grain. The cadmium uptaked by rice were mainly dis-tributed in the stem, which accounted for 41.53%~54.67%of the gross number, the grain just occupied 4.92%~14.36%. The absorptive ca-pacity of cadmium of direct seeding mode was stronger than the other three modes, and the cadmium content of each organ was higher than the other three cultivation modes significantly. Certain relevance exsisted between photosynthetic physiological characteristics and the cad-mium content, accumulation of each rice organ. There were significant correlation between cadmium content of grain absorbed and transpira-tion rate. The correlation coefficient was r=0.684(P=0.029).%本研究以湘早籼45号和陆两优996为材料,研究了不同栽培模式下水稻体内镉(Cd)积累特性及其与光合生理之间的相关性。研究结果表明,在常规水育秧(T1)、软盘育秧(T2)、旱育秧(T3)、直播(T4)4种不同栽培模式下,产量差异达显著水平(P<0.05),2个品种均在直播模式下产量最高;从不同器官来看,镉含量最高的是根系,最高可达10.19 mg·kg-1,其次是茎秆、叶片,稻谷中含量最低;水稻体内重金属镉主要分布在茎秆中,占吸收总量的41.53%~54.67%,稻谷中镉分布量占4.92%~14.36%;直播栽培模式下植株对重金属镉的吸收能力最强,各个器官中的镉均显著高于其他3种栽培模式;光合生理特性与水稻各器官镉含量、积累量具有一定相关性,

  16. Origin of seed shattering in rice (Oryza sativa L.).

    Science.gov (United States)

    Lin, Zhongwei; Griffith, Megan E; Li, Xianran; Zhu, Zuofeng; Tan, Lubing; Fu, Yongcai; Zhang, Wenxu; Wang, Xiangkun; Xie, Daoxin; Sun, Chuanqing

    2007-06-01

    A critical evolutionary step during rice domestication was the elimination of seed shattering. Wild rice disperses seeds freely at maturity to guarantee the propagation, while cultivated rice retains seeds on the straws to make easy harvest and decrease the loss of production. The molecular basis for this key event during rice domestication remains to be elucidated. Here we show that the seed shattering is controlled by a single dominant gene, Shattering1 (SHA1), encoding a member of the trihelix family of plant-specific transcription factors. SHA1 was mapped to a 5.5 kb genomic fragment, which contains a single open reading frame, using a backcrossed population between cultivated rice Teqing and an introgression line IL105 with the seed shattering habit derived from perennial common wild rice, YJCWR. The predicted amino acid sequence of SHA1 in YJCWR and IL105 is distinguished from that in eight domesticated rice cultivars, including Teqing, by only a single amino acid substitution (K79N) caused by a single nucleotide change (g237t). Further sequence verification on the g237t mutation site revealed that the g237t mutation is present in all the domesticated rice cultivars, including 92 indica and 108 japonica cultivars, but not in any of the 24 wild rice accessions examined. Our results demonstrate that the g237t mutation in SHA1 accounts for the elimination of seed shattering, and that all the domesticated rice cultivars harbor the mutant sha1 gene and therefore have lost the ability to shed their seeds at maturity. In addition, our data support the theory that the non-shattering trait selection during rice domestication occurred prior to the indica-japonica differentiation in rice evolutionary history. PMID:17216230

  17. Trace Element Management in Rice

    Directory of Open Access Journals (Sweden)

    Abin Sebastian

    2015-08-01

    Full Text Available Trace elements (TEs are vital for the operation of metabolic pathways that promote growth and structural integrity. Paddy soils are often prone to TE limitation due to intensive cultivation and irrigation practices. Apart from this, rice paddies are potentially contaminated with transition metals such as Cd, which are often referred to as toxic TEs. Deficiency of TEs in the soil not only delays plant growth but also causes exposure of plant roots to toxic TEs. Fine-tuning of nutrient cycling in the rice field is a practical solution to cope with TEs deficiency. Adjustment of soil physicochemical properties, biological process such as microbial activities, and fertilization helps to control TEs mobilization in soil. Modifications in root architecture, metal transporters activity, and physiological processes are also promising approaches to enhance TEs accumulation in grains. Through genetic manipulation, these modifications help to increase TE mining capacity of rice plants as well as transport and trafficking of TEs into the grains. The present review summarizes that regulation of TE mobilization in soil, and the genetic improvement of TE acquisition traits help to boost essential TE content in rice grain.

  18. Research on the Effect of Planting Density on Rice Yield and Quality

    Institute of Scientific and Technical Information of China (English)

    Jing; LI; Jichao; YUAN; Guangze; CAI

    2013-01-01

    Planting density is of great significance in adjusting the population structure of rice,increasing yield and reducing the cost. And suitable planting density can not only bring the yield potential of rice population into full play, obtain the maximum grain yield per unit area, but save labor, protect the environment and improve rice quality. This article summarizes the impact of planting density on rice growth, yield, the components as well as qualities at an attempt to provide theoretical guidance for high yield and quality cultivation of rice.

  19. Practices and Prospects of Super Hybrid Rice Breeding

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The great progress in super rice breeding both in China and other countries has been made in recent years.However, there were three main problems in super rice breeding: 1) the super rice varieties were still rare; 2) most super rice varieties exhibited narrow adaptability; and 3) current breeding theories emphasized too much on the rice growth model, but they were unpractical in guidance for rice breeding. According to the authors' experience on the rice breeding, the breeding strategies including three steps (super parent breeding, super hybrid rice breeding and super hybrid rice seed production)were proposed, and the objectives of each step and the key technologies to achieve the goals were elucidated in detail. The super parent of hybrid rice should exhibit excellent performance in all agronomic traits, with the yield or sink capacity reached the level of the hybrid rice control in regional trials. The super hybrid rice combination should meet the following criteria: good rice quality, wide adaptation, lodging resistance, resistance to main insects and diseases, and the yield exceeded above 8%over the control varieties in the national and provincial regional trials. To achieve the goal, the technical strategies, such as selecting optimal combination of the parents, increasing selection pressure, paying more attention to harmony of ideal plant type, excellent physiological traits and all the agronomic traits, should be emphasized. The yield of seed production should reach 3.75 t/ha and 5.25 t/ha for the super hybrid rice combinations derived from early-season and middle-season types of male sterile lines, respectively. The main technologies for raising seed production yield included selecting optimum seed production site, using the male sterile line with large sink capacity and good outcrossing characteristics, and improving the amount of the pollen by intensive cultivation of the male parent. According to the technologies of the three-step breeding on super

  20. Integrated Pest Management in Rice: Integrating Economics, Extension and Policy

    OpenAIRE

    Martin, John

    1988-01-01

    Since 1980, a project on integrated pest management in rice has been operating in seven countries of the South/South East ASian Region through the Food and Agriculture Organisation. Austral1a has been an instigator and act1 va finanOial '\

  1. Nonindependent domestication of the two rice subspecies, Oryza sativa ssp. indica and ssp. japonica, demonstrated by multilocus microsatellites.

    Science.gov (United States)

    Gao, Li-Zhi; Innan, Hideki

    2008-06-01

    The origins of the Asian cultivated rice Oryza sativa from its wild ancestor O. rufipogon have been debated for decades. The question mainly concerns whether it originated monophyletically or polyphyletically. To shed light on the origins and demographic history of rice domestication, we genotyped a total of 92 individual plants from the two O. sativa subspecies and O. rufipogon for 60 microsatellites. An approximate Bayesian method was applied to estimate demographic parameters for O. rufipogon vs. O. sativa ssp. indica and O. rufipogon vs. O. sativa ssp. japonica. We showed that the japonica subspecies suffered a more severe bottleneck than the indica subspecies and thus a greater loss of genetic variation during its domestication. Across microsatellite loci there is a significant positive correlation in the reduction of genetic diversity between the two subspecies. The results suggest that completely independent domestication of indica and japonica subspecies may not explain our data and that there is at least partial sharing of their ancestral populations and/or recent gene flow between them. PMID:18505887

  2. Asian American Women: A Bibliography.

    Science.gov (United States)

    Yung, Judy, Comp.; And Others

    1978-01-01

    Listed in this bibliography are materials available on Asian American women at the Asian Community Library (Oakland Public Library) and the Asian American Studies Library (University of California, Berkeley). (Author/EB)

  3. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice

    Energy Technology Data Exchange (ETDEWEB)

    Su, J.; Hu, C.; Yan, X.; Jin, Y.; Chen, Z.; Guan, Q.; Wang, Y.; Zhong, D.; Jansson, Georg C.; Wang, F.; Schnrer, Anna; Sun, Chuanxin

    2015-07-22

    Atmospheric methane is the second most important greenhouse gas after carbon dioxide, and is responsible for about 20% of the global warming effect since pre-industrial times. Rice paddies are the largest anthropogenic methane source and produce 7–17% of atmospheric methane. Warm waterlogged soil and exuded nutrients from rice roots provide ideal conditions for methanogenesis in paddies with annual methane emissions of 25–100-million tonnes. This scenario will be exacerbated by an expansion in rice cultivation needed to meet the escalating demand for food in the coming decades4. There is an urgent need to establish sustainable technologies for increasing rice production while reducing methane fluxes from rice paddies. However, ongoing efforts for methane mitigation in rice paddies are mainly based on farming practices and measures that are difficult to implement5. Despite proposed strategies to increase rice productivity and reduce methane emissions4,6, no high-starch low-methane-emission rice has been developed. Here we show that the addition of a single transcription factor gene, barley SUSIBA2, conferred a shift of carbon flux to SUSIBA2 rice, favouring the allocation of photosynthates to aboveground biomass over allocation to roots. The altered allocation resulted in an increased biomass and starch content in the seeds and stems, and suppressed methanogenesis, possibly through a reduction in root exudates. Three-year field trials in China demonstrated that the cultivation of SUSIBA2 rice was associated with a significant reduction in methane emissions and a decrease in rhizospheric methanogen levels. SUSIBA2 rice offers a sustainable means of providing increased starch content for food production while reducing greenhouse gas emissions from rice cultivation. Approaches to increase rice productivity and reduce methane emissions as seen in SUSIBA2 rice may be particularly beneficial in a future climate with rising temperatures resulting in increased methane

  4. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice

    Science.gov (United States)

    Su, J.; Hu, C.; Yan, X.; Jin, Y.; Chen, Z.; Guan, Q.; Wang, Y.; Zhong, D.; Jansson, C.; Wang, F.; Schnürer, A.; Sun, C.

    2015-07-01

    Atmospheric methane is the second most important greenhouse gas after carbon dioxide, and is responsible for about 20% of the global warming effect since pre-industrial times. Rice paddies are the largest anthropogenic methane source and produce 7-17% of atmospheric methane. Warm waterlogged soil and exuded nutrients from rice roots provide ideal conditions for methanogenesis in paddies with annual methane emissions of 25-100-million tonnes. This scenario will be exacerbated by an expansion in rice cultivation needed to meet the escalating demand for food in the coming decades. There is an urgent need to establish sustainable technologies for increasing rice production while reducing methane fluxes from rice paddies. However, ongoing efforts for methane mitigation in rice paddies are mainly based on farming practices and measures that are difficult to implement. Despite proposed strategies to increase rice productivity and reduce methane emissions, no high-starch low-methane-emission rice has been developed. Here we show that the addition of a single transcription factor gene, barley SUSIBA2 (refs 7, 8), conferred a shift of carbon flux to SUSIBA2 rice, favouring the allocation of photosynthates to aboveground biomass over allocation to roots. The altered allocation resulted in an increased biomass and starch content in the seeds and stems, and suppressed methanogenesis, possibly through a reduction in root exudates. Three-year field trials in China demonstrated that the cultivation of SUSIBA2 rice was associated with a significant reduction in methane emissions and a decrease in rhizospheric methanogen levels. SUSIBA2 rice offers a sustainable means of providing increased starch content for food production while reducing greenhouse gas emissions from rice cultivation. Approaches to increase rice productivity and reduce methane emissions as seen in SUSIBA2 rice may be particularly beneficial in a future climate with rising temperatures resulting in increased

  5. Shifting cultivation stability and change: Contrasting pathways of land use and livelihood change in Laos

    DEFF Research Database (Denmark)

    Vongvisouk, Thoumthone; Mertz, Ole; Tongmanivong, Sithong;

    2014-01-01

    it is stable in the central site, where sugarcane is an important cash crop. The impacts of land use change on livelihoods are also diverse. Cash crop producers hold more agricultural land than non-cash crop producers, and rubber and sugarcane producers have fewer rice shortages than non......Rural areas in Laos are experiencing a rapid transformation from traditional rice-based shifting cultivation systems to more permanent and diversified market-oriented cultivation systems. The consequences of these changes for local livelihoods are not well known. This study analyzes the impact...... of shifting cultivation change on the livelihood of rural people in six villages in three districts of northern and central Laos. Focus group discussions and household interview questionnaires were employed for data collection. The study reveals that the shifting cultivation of rice is still important...

  6. Effects of ridge tillage on photosynthesis and root characters of rice

    Directory of Open Access Journals (Sweden)

    Yao Yuan-zhi

    2015-03-01

    Full Text Available Rice (Oryza sativa L. is an important crop and breeding has not been able to improve yield. Root characteristics of hybrid rice 'Zhuliangyou 02' under conventional tillage and ridge tillage were studied in a Calcisols in Huaihua, China, from 2011 to 2013 to find better tillage methods to resolve massive water consumption, improve yield, and enhance productivity of agricultural labor for rice cultivation. Results showed ridge tillage increased photosynthetic parameters such as photosynthetic rate (P N, stomatal conductance (g s, and water use efficiency (WUE. It also significantly enhanced rice root number, root activity, and antioxidant enzyme activities; it also increased effective panicle number and actual yield by 22.12% and 15.18%, respectively, and enhanced aerenchymae during the early growth stage. Overall, ridge tillage could promote hybrid rice yields by enhancing root absorption, gas exchange, and reducing water consumption. It could be widely used in rice cultivation.

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

    OpenAIRE

    WANG Kun; Peng, Xiaojue; Ji, Yanxiao; Yang, Pingfang; Zhu, Yingguo; LI, SHAOQING

    2013-01-01

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

  8. Planting Performance and High-yielding Cultivation Techniques of Hybrid Middle Rice Combination Chuanyou 651 in Jianyang County%杂交中稻川优651在建阳种植表现及高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    罗祠平

    2014-01-01

    川优651系南平市农科所用自主选育的恢复系南恢651与四川省农科院作物所选育的不育系川香29A配组育成的籼型杂交中稻新品种,于2011年通过福建省农作物品种审定。总结了川优651在建阳2a试种表现及高产栽培技术。%Chuanyou 651, derived from the CMS line Chuanxiang 29A and a restorer line Nanhui 651, was a new hybrid rice combination developed by Nanping Institute of Agricultural Science and Crop Research Institute, Sichuan Academy of Agricultural Sciences. Chuanyou 651 was registered and released in 2011 in Fujian province. In this paper, we introduced planting performance and high-yielding cultivation techniques of Chuanyou 651 in Jianyang county.

  9. Planting Performance and High-yielding Cultivation Techniques for Heavy-panicle Type Hybrid Rice Combination Yongyou 17 at Jianyang City%重穗型杂交稻甬优17在建阳试种表现及高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    李正美

    2014-01-01

    A new indica-japonica hybrid rice combination, Yongyou 17, was developed by Crop Research Institute of Ningbo Academy of Agricultural Sciences, Zhengjiang Province and Ningbo Seed Co. Ltd. It was grown at Jiangkou town of Jianyang city in 2013, exhibiting tough stem, strong resistant lodging, medium growth duration, good adaptability, large spikelet and more grains, high yield, and fine quality. In order to promote the extension and application of this variety, its high-yielding cultivation techniques were summarized.%甬优17是浙江省宁波市农业科学研究院作物研究所和宁波市种子有限公司育成的籼粳杂交新品种。2013年在建阳市将口镇种植,表现出茎秆坚韧、抗倒性强,生育期适中、适应性好,穗大粒多、产量高,米质优良。为促进该品种的推广应用,总结其高产栽培技术。

  10. Can rice field channels contribute to biodiversity conservation in Southern Brazilian wetlands?

    Science.gov (United States)

    Maltchik, Leonardo; Rolon, Ana Silvia; Stenert, Cristina; Machado, Iberê Farina; Rocha, Odete

    2011-12-01

    Conservation of species in agroecosystems has attracted attention. Irrigation channels can improve habitats and offer conditions for freshwater species conservation. Two questions from biodiversity conservation point of view are: 1) Can the irrigated channels maintain a rich diversity of macrophytes, macroinvertebrates and amphibians over the cultivation cycle? 2) Do richness, abundance and composition of aquatic species change over the rice cultivation cycle? For this, a set of four rice field channels was randomly selected in Southern Brazilian wetlands. In each channel, six sample collection events were carried out over the rice cultivation cycle (June 2005 to June 2006). A total of 160 taxa were identified in irrigated channels, including 59 macrophyte species, 91 taxa of macroinvertebrate and 10 amphibian species. The richness and abundance of macrophytes, macroinvertebrates and amphibians did not change significantly over the rice cultivation cycle. However, the species composition of these groups in the irrigation channels varied between uncultivated and cultivated periods. Our results showed that the species diversity found in the irrigation channels, together with the permanence of water enables these man-made aquatic networks to function as important systems that can contribute to the conservation of biodiversity in regions where the wetlands were converted into rice fields. The conservation of the species in agriculture, such as rice field channels, may be an important alternative for biodiversity conservation in Southern Brazil, where more than 90% of wetland systems have already been lost and the remaining ones are still at high risk due to the expansion of rice production.

  11. Can rice field channels contribute to biodiversity conservation in Southern Brazilian wetlands?

    Science.gov (United States)

    Maltchik, Leonardo; Rolon, Ana Silvia; Stenert, Cristina; Machado, Iberê Farina; Rocha, Odete

    2011-12-01

    Conservation of species in agroecosystems has attracted attention. Irrigation channels can improve habitats and offer conditions for freshwater species conservation. Two questions from biodiversity conservation point of view are: 1) Can the irrigated channels maintain a rich diversity of macrophytes, macroinvertebrates and amphibians over the cultivation cycle? 2) Do richness, abundance and composition of aquatic species change over the rice cultivation cycle? For this, a set of four rice field channels was randomly selected in Southern Brazilian wetlands. In each channel, six sample collection events were carried out over the rice cultivation cycle (June 2005 to June 2006). A total of 160 taxa were identified in irrigated channels, including 59 macrophyte species, 91 taxa of macroinvertebrate and 10 amphibian species. The richness and abundance of macrophytes, macroinvertebrates and amphibians did not change significantly over the rice cultivation cycle. However, the species composition of these groups in the irrigation channels varied between uncultivated and cultivated periods. Our results showed that the species diversity found in the irrigation channels, together with the permanence of water enables these man-made aquatic networks to function as important systems that can contribute to the conservation of biodiversity in regions where the wetlands were converted into rice fields. The conservation of the species in agriculture, such as rice field channels, may be an important alternative for biodiversity conservation in Southern Brazil, where more than 90% of wetland systems have already been lost and the remaining ones are still at high risk due to the expansion of rice production. PMID:22208101

  12. Optimal fertilizer N rates and yield-scaled global warming potential in drill seeded rice

    Science.gov (United States)

    Drill seeded rice (Oryza sativa L.) is the dominant rice cultivation practice in the USA. Although drill seeded systems can lead to significant methane and nitrous oxide emissions due to the presence of both anaerobic and aerobic soil conditions, the relationship between high-yielding management pr...

  13. Evaluating leaf and canopy reflectance of stressed rice plants to monitor arsenic contamination

    Science.gov (United States)

    Arsenic contamination is a serious problem in rice cultivated soils of many developing countries. Hence, it is critical to monitor and control arsenic uptake in rice plants to avoid adverse effects on human health. This study evaluated the feasibility of using reflectance spectroscopy to monitor ars...

  14. Statistical inference of selection and divergence of rice blast resistance gene Pi-ta

    Science.gov (United States)

    The resistance gene Pi-ta has been effectively used to control rice blast disease worldwide. A few recent studies have described the possible evolution of Pi-ta in cultivated and weedy rice. However, evolutionary statistics used for the studies are too limited to precisely understand selection and d...

  15. Zhe 9248-a new scented rice fine cames out in Zhejiang

    Institute of Scientific and Technical Information of China (English)

    WANGKaizhi

    1994-01-01

    This novel rice line is developed recently by a research team led by Associate Prof QIU Baiqin, Crop Breeding and Cultivation Institute, Zhejiang Academy of Agricultural Sciences. Zhe 9248 is of high resistance to blast, early mature and of higher yield. Being soft, smooth, and glossy, the cooked rice of “Zhe 9248” has excellent eating quality.

  16. Relationships of wild and domesticated rices (Oryza AA genome species) based upon whole chloroplast genome sequences

    OpenAIRE

    Wambugu, Peterson W.; Marta Brozynska; Agnelo Furtado; Daniel L. Waters; Robert J. Henry

    2015-01-01

    Rice is the most important crop in the world, acting as the staple food for over half of the world’s population. The evolutionary relationships of cultivated rice and its wild relatives have remained contentious and inconclusive. Here we report on the use of whole chloroplast sequences to elucidate the evolutionary and phylogenetic relationships in the AA genome Oryza species, representing the primary gene pool of rice. This is the first study that has produced a well resolved and strongly su...

  17. 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.

  18. Molecular Evolution of the TAC1 Gene from Rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    Jiahuan Jiang; Lubin Tan; Zuofeng Zhu; Yongcai Fu; Fengxia Liu; Hongwei Cai; Chuanqing Sun

    2012-01-01

    Tiller angle is a key feature of the architecture of cultivated rice (Oryza sativa),since it determines planting density and influences rice yield.Our previous work identified Tiller Angle Control 1 (TAC1) as a major quantitative trait locus that controls rice tiller angle.To further clarify the evolutionary characterization of the TAC1 gene,we compared a TAC1-containing 3164-bp genomic region among 113 cultivated varieties and 48 accessions of wild rice,including 43 accessions of O.rufipogon and five accessions of O.nivara.Only one single nucleotide polymorphism (SNP),a synonymous substitution,was detected in TAC1 coding regions of the cultivated rice varieties,whereas one synonymous and one nonsynonymous SNP were detected among the TAC1 coding regions of wild rice accessions.These data indicate that little natural mutation and modification in the TAC1 coding region occurred within the cultivated rice and its progenitor during evolution.Nucleotide diversities in the TAC1 gene regions of O.sativa and O.rufipogon of 0.00116 and 0.00112,respectively,further indicate that TAC1 has been highly conserved during the course of rice domestication.A functional nucleotide polymorphism (FNP) of TAC1 was only found in the japonica rice group.A neutrality test revealed strong selection,especially in the 3'-flanking region of the TAC1 coding region containing the FNP in the japonica rice group.However,no selection occurred in the indica and wild-rice groups.A phylogenetic tree derived from TAC1 sequence analysis suggests that the indica and japonica subspecies arose independently during the domestication of wild rice.

  19. Mapping Flooded Rice Paddies Using Time Series of MODIS Imagery in the Krishna River Basin, India

    OpenAIRE

    Pardhasaradhi Teluguntla; Dongryeol Ryu; Biju George; Walker, Jeffrey P.; Hector M. Malano

    2015-01-01

    Rice is one of the major crops cultivated predominantly in flooded paddies, thus a large amount of water is consumed during its growing season. Accurate paddy rice maps are therefore important inputs for improved estimates of actual evapotranspiration in the agricultural landscape. The main objective of this study was to obtain flooded paddy rice maps using multi-temporal images of Moderate Resolution Imaging Spectroradiometer (MODIS) in the Krishna River Basin, India. First, ground-based spe...

  20. Asian American Cultural Resistance.

    Science.gov (United States)

    Libretti, Tim

    1997-01-01

    Explores the encounter of Marxism and Asian American literary theory and imagines an Asian American Marxism. To do so requires theorizing race, class, and gender not as substantive categories of antagonisms but as complementary and coordinated elements of a totality of social relations structuring racial patriarchal capitalism. (SLD)

  1. Recent Progress on Rice Genetics in China

    Institute of Scientific and Technical Information of China (English)

    Hua Jiang; Long-Biao Quo; Qian Qian

    2007-01-01

    Through thousands of years of evolution and cultivation, tremendously rich genetic diversity has been accumulated in rice (Oryza sativa L.), developing a large germplasm pool from which people can select varieties with morphologies of interest and other important agronomic traits. With the development of modern genetics, scientists have paid more attention to the genetic value of these elite varieties and germplasms, and such rich rice resources provide a good foundation for genetic research in China. Approximately 100 000 accessions of radiation-, chemical- or insertion-induced mutagenesis have been generated since the 1980s, and great progress has been made on rice molecular genetics. So far at least 16 variant/mutant genes including MOC1, BC1, SKC1, and Rf genes have been isolated and characterized in China. These achievements greatly promote the research on functional genomics, understanding the mechanism of plant development and molecular design breeding of rice in China. Here we review the progress of three aspects of rice genetics in China: moving forward at the molecular level, genetic research on elite varieties and germplasms, and new gene screening and genetic analysis using mutants. The prospects of rice genetics are also discussed.

  2. Balanço de nutrientes e da fitomassa em um Argissolo Amarelo sob floresta tropical amazônica após a queima e cultivo com arroz Nutrient and phytomass dynamics in a yellow Argissol under Amazonian tropical forest after burning and rice cultivation

    Directory of Open Access Journals (Sweden)

    F. A. R. Sampaio

    2003-12-01

    burned areas with cultivation of rice (cultivated. Furthermore, these areas were compared with an area of primary vegetation (forest used as reference. Burning consumed 36.3% of the initial biomass and produced 5.5 Mg ha-1 of ashes with significant amounts of nutrients, mainly Ca, Mg, and K. To clear areas by means of burning turned out to be a practice of low efficiency, because only a small percentage of the original biomass was converted into ashes and the greatest part remained in the form of residues. Even with the restitution of nutrients such as Ca, Mg, K by rain, there was a considerable removal of N, P, K, Ca, Mg, and S, on the one hand by direct action of the fire, on the other through the carrying off of the ashes by the wind, and/or the removal by the crop. Results indicated that nutrient loss in the burned uncultivated area was greater than in the burned cultivated one, demonstrating the importance of soil covering to keep the elements in the system. At the end of the culture cycle, the residual effect of the ashes was still noticeable in the system, clearly expressed by the P, K, Ca, and Mg values which were higher than those measured in the control area (forest.

  3. 中浙优8号作中稻种植表现及高产栽培技术%Planting performance and cultivation techniques for"zhongzheyou8"planted as semilate rice

    Institute of Scientific and Technical Information of China (English)

    李正美

    2015-01-01

    "Zhongzheyou8"was planted in Jianyang City,and it performed good plant type,dark green leaves,strong tille-ring capacity,big grain,high seed setting rate,high yielding and good quality. In this paper its planting performance and high-yield cultivation techniques in Jianyang City were summarized.%中浙优8号在建阳市种植,表现株型挺拔、叶色深绿、分蘖力较强、穗大粒多、结实率高、丰产性较好、米质优良.总结中浙优8号在建阳市推广种植表现及其高产栽培技术.

  4. How Do New Cash Crops Spread or Not Spread?: The Case of Rice in a Suburban Area, Ghana

    OpenAIRE

    Tachibana, Towa; Sakurai, Takeshi

    2012-01-01

    This paper examines the determinants of rice-cultivation adoption in inland-valley bottom areas in Ghana. In West African countries, surging import of rice has shown farmers a new and potentially huge income source. Around the second largest urban area in Ghana, Kumsi, there are inland-valley bottoms which are suitable for rain-fed rice cultivation. The puzzle is that not much part of these inland-valley bottoms has been utilized for rice production. In 2001, in four villages around Kumasi, w...

  5. Controlling rice bacterial blight in Africa : needs and prospects

    OpenAIRE

    Verdier, Valérie; Cruz, C.V.; Leach, J. E.

    2012-01-01

    Rice cultivation has drastically increased in Africa over the last decade. During this time, the region has also seen a rise in the incidence of rice bacterial blight caused by the pathogen Xanthomonas oryzae pv. oryzae. The disease is expanding to new rice production areas and threatens food security in the region. Yield losses caused by X. oryzae pv. oryzae range from 20 to 30% and can be as high as 50% in some areas. Employing resistant cultivars is the most economical and effective way to...

  6. Diversity of malaria in rice growing areas of the Afrotropical region.

    Science.gov (United States)

    Carnevale, P; Guillet, P; Robert, V; Fontenille, D; Doannio, J; Coosemans, M; Mouchet, J

    1999-09-01

    It is well known that 'in many instances the rice agrosystem perfectly fits the ecological requirements of pathogens or vectors' and in fact 'malaria, schistosomiasis and Japanese encephalitis are important vector-borne diseases associated with rice production in developing countries' (IRRI, 1987). In spite of these fears, rice cultivation has been on the increase in the African region in response to demographic and economic pressures. However, although rice fields provide suitable breeding places for Anopheles mosquitoes and rice cultivation leads to an increase in the biting rates, the species which are adapted to these sites are not the same in all parts of Africa. Several examples illustrate this phenomenon: An. funestus in the rice fields of Madagascar, An. pharoensis in saline water rice fields in the delta of the Senegal river, An. arabiensis in northern Cameroon and Burundi, An. gambiae Mopti form in the Kou Valley (Burkina Faso) and An. gambiae Savanna form in the rice fields of Kafine near Bouaké (Côte d'Ivoire). The vectorial capacities of these species are not the same and malaria inoculation rates are not necessarily increased in the riceland agroecosystem. The consequences for malaria of introducing rice cultivation depend on the situation before its introduction: it could be worsened in unstable malaria areas but not in stable malaria areas. Therefore, sound epidemiological and entomological knowledge are needed before causing any environmental modifications for agricultural purposes and there should be regular monitoring to avoid any outbreak.

  7. A MULTIDISCIPLINARY AND INTEGRATED STUDY OF RICE PRECISION FARMING

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In terms of demands of rice farming in the southern China, the information processing system and the yield measurement system that is installed in combine harvester, are designed and completed. Now the systems have been used in demonstration site in the Experiment Base of Shanghai Precision Agriculture. Based on the idea of spatial-oriented, object-oriented, user-oriented, the Farm Geographic Information System for precision farming of rice was developed, which is characterized by intelligence and visualized. The Decision-making Management System is integrated with rice growth model, expert model for rice cultivation. The DGPS, RS, GIS and intelligence sensors and computer technique were adopted in building the artificial intelligence system for measuring grain yield that is installed in combine harvester, so the combine harvester could provide the grain yield distribution map real-timely. The environmental and economic assessment shows that the precision rice farming applied in the demonstration site will benefit the society, economy and ecology greatly.

  8. Functional diversity of jasmonates in rice.

    Science.gov (United States)

    Liu, Zheng; Zhang, Shumin; Sun, Ning; Liu, Hongyun; Zhao, Yanhong; Liang, Yuling; Zhang, Liping; Han, Yuanhuai

    2015-12-01

    Phytohormone jasmonates (JA) play essential roles in plants, such as regulating development and growth, responding to environmental changes, and resisting abiotic and biotic stresses. During signaling, JA interacts, either synergistically or antagonistically, with other hormones, such as salicylic acid (SA), gibberellin (GA), ethylene (ET), auxin, brassinosteroid (BR), and abscisic acid (ABA), to regulate gene expression in regulatory networks, conferring physiological and metabolic adjustments in plants. As an important staple crop, rice is a major nutritional source for human beings and feeds one third of the world's population. Recent years have seen significant progress in the understanding of the JA pathway in rice. In this review, we summarize the diverse functions of JA, and discuss the JA interplay with other hormones, as well as light, in this economically important crop. We believe that a better understanding of the JA pathway will lead to practical biotechnological applications in rice breeding and cultivation. PMID:26054241

  9. Characterization of paralogous protein families in rice

    Directory of Open Access Journals (Sweden)

    Zhu Wei

    2008-02-01

    Full Text Available Abstract Background High gene numbers in plant genomes reflect polyploidy and major gene duplication events. Oryza sativa, cultivated rice, is a diploid monocotyledonous species with a ~390 Mb genome that has undergone segmental duplication of a substantial portion of its genome. This, coupled with other genetic events such as tandem duplications, has resulted in a substantial number of its genes, and resulting proteins, occurring in paralogous families. Results Using a computational pipeline that utilizes Pfam and novel protein domains, we characterized paralogous families in rice and compared these with paralogous families in the model dicotyledonous diploid species, Arabidopsis thaliana. Arabidopsis, which has undergone genome duplication as well, has a substantially smaller genome (~120 Mb and gene complement compared to rice. Overall, 53% and 68% of the non-transposable element-related rice and Arabidopsis proteins could be classified into paralogous protein families, respectively. Singleton and paralogous family genes differed substantially in their likelihood of encoding a protein of known or putative function; 26% and 66% of singleton genes compared to 73% and 96% of the paralogous family genes encode a known or putative protein in rice and Arabidopsis, respectively. Furthermore, a major skew in the distribution of specific gene function was observed; a total of 17 Gene Ontology categories in both rice and Arabidopsis were statistically significant in their differential distribution between paralogous family and singleton proteins. In contrast to mammalian organisms, we found that duplicated genes in rice and Arabidopsis tend to have more alternative splice forms. Using data from Massively Parallel Signature Sequencing, we show that a significant portion of the duplicated genes in rice show divergent expression although a correlation between sequence divergence and correlation of expression could be seen in very young genes. Conclusion

  10. Lead and Cadmium Content of Korbal Rice in Northern Iran

    Directory of Open Access Journals (Sweden)

    A Bakhtiarian

    2001-09-01

    Full Text Available Every year the entrance of factory wastes such as Shiraz Petrochemical Complex, Marvdasht sugar cube factory, and Charmineh factory, and other industrial units into the Kor and Sivand rivers and also the entrance of the Marvdasht and Zarghan city sewer system wastes into the Kor river and the use of their water in the cultivation of the rice has caused a significant increase in the lead and cadmium content of the grains of rice. To study the effect of the Kor river's pollution on the lead and cadmium content of the Korbal rice samples. The results of the study show that the lead and cadmium content of the grains of rice, 57 samples of 6 different types of rice were prepared in 19 different stations in Korbal region and also 18 samples of 6 different types of rice, cultivated with unpolluted water, were prepared in the National Institute of Rice Research (Gilan. A comparison of the pollution level of the Korbal and Gilan rice samples shows a significant difference and indicates the significant effect of the pollution of the river on the lead and cadmium content of the Korbal rice samples. The results of the study show that the lead and cadmium content of the hybrid, prolific, and late rice sample types were greater than that of unprolific and early types, such that the amount of these two elements were highest in the Hassani type (the lead content was 0.9625 ppm and the cadmium content was 0.0793 ppm, whereas the Gasroddashti type which blooms earlier and is long seeded has the lowest amount of these two elements.

  11. Survey of Rice Cropping Systems in Kampong Chhnang Province, Cambodia

    Institute of Scientific and Technical Information of China (English)

    Volker KLEINHENZ; Sophon CHEA; Ngin HUN

    2013-01-01

    Although Cambodia might have achieved self-sufficiency and an exported surplus in rice production,its rice-based farming systems are widely associated with low productivity,low farmer income and rural poverty.The study is based on a questionnaire village survey in 14 communes containing 97 villages of Kampong Chhnang Province from March to June,2011.It analyzes the prevailing rice-based cropping systems and evaluates options for their improvement.Differences in cropping systems depend on the distance from the Tonle Sap water bodies.At distances greater than 10 km,transplanted wet-season rice cropping system with low productivity of about 1.6 t/hm2 prevails.This deficiency can be primarily attributed to soils with high coarse sand fractions and low pH (< 4.0),use of ‘late' cultivars,and exclusive use of self-propagated seeds.To improve this cropping system,commercial ‘medium' cultivars help prevent crop failure by shortening the cultivation period by one month and complementation of wet-season rice with non-rice crops should be expanded.Areas adjacent (≤ 1 km) to the water bodies become inundated for up to seven months between July until January of each year.In this area,soils contain more fine sand,silt and clay,and their pH is higher (> 4.0).Farmers predominantly cultivate dry-season recession rice between January and April.Seventy-nine percent of the area is sown directly and harvested by combines.Adoption ratio of commercial rice seeds is 59%and yields average 3.2 t/hm2.Introduction of the second dry-season rice between April and July may double annual yields in this rice cropping system.Besides upgrading other cultivation technologies,using seeds from commercial sources will improve yield and rice quality.Along with rice,farmers grow non-rice crops at different intensities ranging from single annual crops to intensive sequences at low yields.

  12. Accumulation of arsenic in tissues of rice plant (Oryza sativa L.) and its distribution in fractions of rice grain.

    Science.gov (United States)

    Rahman, M Azizur; Hasegawa, H; Rahman, M Mahfuzur; Rahman, M Arifur; Miah, M A M

    2007-10-01

    A study was conducted to investigate the accumulation and distribution of arsenic in different fractions of rice grain (Oryza sativa L.) collected from arsenic affected area of Bangladesh. The agricultural soil of study area has become highly contaminated with arsenic due to the excessive use of arsenic-rich underground water (0.070+/-0.006 mg l(-1), n=6) for irrigation. Arsenic content in tissues of rice plant and in fractions of rice grain of two widely cultivated rice varieties, namely BRRI dhan28 and BRRI hybrid dhan1, were determined. Regardless of rice varieties, arsenic content was about 28- and 75-folds higher in root than that of shoot and raw rice grain, respectively. In fractions of parboiled and non-parboiled rice grain of both varieties, the order of arsenic concentrations was; rice hull>bran-polish>brown rice>raw rice>polish rice. Arsenic content was higher in non-parboiled rice grain than that of parboiled rice. Arsenic concentrations in parboiled and non-parboiled brown rice of BRRI dhan28 were 0.8+/-0.1 and 0.5+/-0.0 mg kg(-1) dry weight, respectively while those of BRRI hybrid dhan1 were 0.8+/-0.2 and 0.6+/-0.2 mg kg(-1) dry weight, respectively. However, parboiled and non-parboiled polish rice grain of BRRI dhan28 contained 0.4+/-0.0 and 0.3+/-0.1 mg kg(-1) dry weight of arsenic, respectively while those of BRRI hybrid dhan1 contained 0.43+/-0.01 and 0.5+/-0.0 mg kg(-1) dry weight, respectively. Both polish and brown rice are readily cooked for human consumption. The concentration of arsenic found in the present study is much lower than the permissible limit in rice (1.0 mg kg(-1)) according to WHO recommendation. Thus, rice grown in soils of Bangladesh contaminated with arsenic of 14.5+/-0.1 mg kg(-1) could be considered safe for human consumption. PMID:17599387

  13. Caracterização da fração protéica da cianobactéria Aphanothece Microscopica Nägeli cultivada no efluente da parboilização do arroz Protein characterisation of the Aphanothece Microscopica Nägeli cyanobacterium cultivated in parboiled rice effluent

    Directory of Open Access Journals (Sweden)

    Eduardo Jacob-Lopes

    2006-06-01

    Full Text Available O objetivo do presente trabalho foi avaliar a fração protéica da cianobactéria Aphanothece microscopica Nägeli cultivada no efluente da parboilização do arroz quando submetida a diferentes condições de secagem. A produção da biomassa foi realizada a partir da água residuária do processo de parboilização do arroz em bioreatores de coluna de bolhas. A biomassa foi separada do efluente por centrifugação e desidratada em secador descontínuo de bandejas nas condições de 40, 50 e 60ºC e espessuras de bandejas de 5 e 7 mm. O comportamento eletroforético das proteínas da biomassa foi analisado por eletroforese em gel de poliacrilamamida na presença de dodecil sulfato de sódio (SDS-PAGE e apresentou bandas com peso molecular de 15 kDa a 62,5 kDa. O perfil aminoacídico mostrou teores superiores aos recomendados pelo padrão FAO, com exceção dos aminoácidos lisina e dos sulfurados (MET+CYS. A caracterização funcional, expressa em termos de solubilidade e capacidade emulsificante, demonstrou a influência da condição de secagem na funcionalidade protéica da biomassa.The objective of the present work was to evaluate the protein fraction of Aphanothece microscopica Nägeli cyanobacteria cultivated in the parboiled rice effluent, submitted to different drying conditions. The production of the biomass was done by using wastewater from the process of rice parboiling in a bubble column bioreactor. The biomass was separated from the effluent by centrifugation and dehydrated in a tray dryer at 40, 50 and 60ºC and thicknesses of 5 and 7 mm. The eletroforetic profile of proteins of the biomass was analysed by SDS-PAGE and presented bands with molecular weight between 62.5-15kDa. The amino acid profile was higher than the concentrations recommended by standard FAO, with the exception of the amino acids (LYS and the sulphurated (MET+CYS. The functional properties characterisation in terms of protein solubility and emulsification

  14. Proteomics of Rice Seed Germination

    Directory of Open Access Journals (Sweden)

    Dongli eHe

    2013-07-01

    Full Text Available Seed is a condensed form of plant. Under suitable environmental conditions, it can resume the metabolic activity from physiological quiescent status, and mobilize the reserves, biosynthesize new proteins, regenerate organelles and cell membrane, eventually protrude the radicle and enter into seedling establishment. So far, how these activities are regulated in a coordinated and sequential manner is largely unknown. With the availability of more and more genome sequence information and the development of mass spectrometry (MS technology, proteomics has been widely applied in analyzing the mechanisms of different biological processes, and proved to be very powerful. Regulation of rice seed germination is critical for rice cultivation. In recent years, a lot of proteomic studies have been conducted in exploring the gene expression regulation, reserves mobilization and metabolisms reactivation, which brings us new insights on the mechanisms of metabolism regulation during this process. Nevertheless, it also invokes a lot of questions. In this mini-review, we summarized the progress in the proteomic studies of rice seed germination. The current challenges and future perspectives were also discussed, which might be helpful for the following studies.

  15. Adulteration and cultivation region identification of American ginseng using HPLC coupled with multivariate analysis.

    Science.gov (United States)

    Yu, Chunhao; Wang, Chong-Zhi; Zhou, Chun-Jie; Wang, Bin; Han, Lide; Zhang, Chun-Feng; Wu, Xiao-Hui; Yuan, Chun-Su

    2014-10-01

    American ginseng (Panax quinquefolius) is originally grown in North America. Due to price difference and supply shortage, American ginseng recently has been cultivated in northern China. Further, in the market, some Asian ginsengs are labeled as American ginseng. In this study, forty-three American ginseng samples cultivated in the USA, Canada or China were collected and 14 ginseng saponins were determined using HPLC. HPLC coupled with hierarchical cluster analysis and principal component analysis was developed to identify the species. Subsequently, an HPLC-linear discriminant analysis was established to discriminate cultivation regions of American ginseng. This method was successfully applied to identify the sources of 6 commercial American ginseng samples. Two of them were identified as Asian ginseng, while 4 others were identified as American ginseng, which were cultivated in the USA (3) and China (1). Our newly developed method can be used to identify American ginseng with different cultivation regions. PMID:25044150

  16. Recent advances in the dissection of drought-stress regulatory networks and strategies for development of drought-tolerant transgenic rice plants

    OpenAIRE

    Daisuke eTodaka; Kazuo eShinozaki; Kazuko eYamaguchi-Shinozaki

    2015-01-01

    Advances have been made in the development of drought-tolerant transgenic plants, including cereals. Rice, one of the most important cereals, is considered to be a critical target for improving drought tolerance, as present-day rice cultivation requires large quantities of water and as drought-tolerant rice plants should be able to grow in small amounts of water. Numerous transgenic rice plants showing enhanced drought tolerance have been developed to date. Such genetically engineered plants ...

  17. Aerobic rice: crop performance and water use efficiency

    Directory of Open Access Journals (Sweden)

    Chiara Grassi

    2011-11-01

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

  18. Timing is everything: early degradation of abscission layer is associated with increased seed shattering in U.S. weedy rice

    Directory of Open Access Journals (Sweden)

    Hepler Peter K

    2011-01-01

    Full Text Available Abstract Background Seed shattering, or shedding, is an important fitness trait for wild and weedy grasses. U.S. weedy rice (Oryza sativa is a highly shattering weed, thought to have evolved from non-shattering cultivated ancestors. All U.S. weedy rice individuals examined to date contain a mutation in the sh4 locus associated with loss of shattering during rice domestication. Weedy individuals also share the shattering trait with wild rice, but not the ancestral shattering mutation at sh4; thus, how weedy rice reacquired the shattering phenotype is unknown. To establish the morphological basis of the parallel evolution of seed shattering in weedy rice and wild, we examined the abscission layer at the flower-pedicel junction in weedy individuals in comparison with wild and cultivated relatives. Results Consistent with previous work, shattering wild rice individuals possess clear, defined abscission layers at flowering, whereas non-shattering cultivated rice individuals do not. Shattering weedy rice from two separately evolved populations in the U.S. (SH and BHA show patterns of abscission layer formation and degradation distinct from wild rice. Prior to flowering, the abscission layer has formed in all weedy individuals and by flowering it is already degrading. In contrast, wild O. rufipogon abscission layers have been shown not to degrade until after flowering has occurred. Conclusions Seed shattering in weedy rice involves the formation and degradation of an abscission layer in the flower-pedicel junction, as in wild Oryza, but is a developmentally different process from shattering in wild rice. Weedy rice abscission layers appear to break down earlier than wild abscission layers. The timing of weedy abscission layer degradation suggests that unidentified regulatory genes may play a critical role in the reacquisition of shattering in weedy rice, and sheds light on the morphological basis of parallel evolution for shattering in weedy and wild

  19. Human exposure to mercury in a compact fluorescent lamp manufacturing area: By food (rice and fish) consumption and occupational exposure

    International Nuclear Information System (INIS)

    To investigate human Hg exposure by food consumption and occupation exposure in a compact fluorescent lamp (CFL) manufacturing area, human hair and rice samples were collected from Gaohong town, Zhejiang Province, China. The mean values of total mercury (THg) and methylmercury (MeHg) concentrations in local cultivated rice samples were significantly higher than in commercial rice samples which indicated that CFL manufacturing activities resulted in Hg accumulation in local rice samples. For all of the study participants, significantly higher THg concentrations in human hair were observed in CFL workers compared with other residents. In comparison, MeHg concentrations in human hair of residents whose diet consisted of local cultivated rice were significantly higher than those who consumed commercial rice. These results demonstrated that CFL manufacturing activities resulted in THg accumulation in the hair of CFL workers. However, MeHg in hair were mainly affected by the sources of rice of the residents. - Highlights: • Rice samples were contaminated by Compact fluorescent lamp (CFL) manufacturing. • CFL manufacturing lead to THg accumulation in human hair. • MeHg in human hair were mainly affected by the sources of rice. • MeHg intake from fish consumption was lower than that from rice consumption. • PDI of MeHg by food consumption was below the guidelines for public health concern. - CFL manufacturing activities result in Hg accumulation in local rice samples and hair of CFL workers. However, MeHg in hair were mainly affected by sources of rice

  20. Unravelling the proteomic profile of rice meiocytes during early meiosis

    Science.gov (United States)

    Collado-Romero, Melania; Alós, Enriqueta; Prieto, Pilar

    2014-01-01

    Transfer of genetic traits from wild or related species into cultivated rice is nowadays an important aim in rice breeding. Breeders use genetic crosses to introduce desirable genes from exotic germplasms into cultivated rice varieties. However, in many hybrids there is only a low level of pairing (if existing) and recombination at early meiosis between cultivated rice and wild relative chromosomes. With the objective of getting deeper into the knowledge of the proteins involved in early meiosis, when chromosomes associate correctly in pairs and recombine, the proteome of isolated rice meiocytes has been characterized by nLC-MS/MS at every stage of early meiosis (prophase I). Up to 1316 different proteins have been identified in rice isolated meiocytes in early meiosis, being 422 exclusively identified in early prophase I (leptotene, zygotene, or pachytene). The classification of proteins in functional groups showed that 167 were related to chromatin structure and remodeling, nucleic acid binding, cell-cycle regulation, and cytoskeleton. Moreover, the putative roles of 16 proteins which have not been previously associated to meiosis or were not identified in rice before, are also discussed namely: seven proteins involved in chromosome structure and remodeling, five regulatory proteins [such as SKP1 (OSK), a putative CDK2 like effector], a protein with RNA recognition motifs, a neddylation-related protein, and two microtubule-related proteins. Revealing the proteins involved in early meiotic processes could provide a valuable tool kit to manipulate chromosome associations during meiosis in rice breeding programs. The data have been deposited to the ProteomeXchange with the PXD001058 identifier. PMID:25104955

  1. 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.

  2. The South Asian genome.

    Directory of Open Access Journals (Sweden)

    John C Chambers

    Full Text Available The genetic sequence variation of people from the Indian subcontinent who comprise one-quarter of the world's population, is not well described. We carried out whole genome sequencing of 168 South Asians, along with whole-exome sequencing of 147 South Asians to provide deeper characterisation of coding regions. We identify 12,962,155 autosomal sequence variants, including 2,946,861 new SNPs and 312,738 novel indels. This catalogue of SNPs and indels amongst South Asians provides the first comprehensive map of genetic variation in this major human population, and reveals evidence for selective pressures on genes involved in skin biology, metabolism, infection and immunity. Our results will accelerate the search for the genetic variants underlying susceptibility to disorders such as type-2 diabetes and cardiovascular disease which are highly prevalent amongst South Asians.

  3. Glaucoma in Asian Populations

    Science.gov (United States)

    ... Us Donate In This Section Glaucoma In Asian Populations email Send this article to a friend by ... an even more serious problem as the world population and longevity increases. The other major glaucoma type ...

  4. Central Asian Republic Info

    Data.gov (United States)

    US Agency for International Development — CAR Info is designed and managed by the Central Asian Republic Mission to fill in the knowledge and reporting gaps in existing agency systems for that Mission. It...

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

    Science.gov (United States)

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

    2009-07-01

    The consumption of arsenic (As) contaminated rice is an important exposure route for humans in countries where rice cultivation employs As contaminated irrigation water. Arsenic toxicity and mobility are a function of its chemical-speciation. The distribution and identification of As in the rice plant are hence necessary to determine the uptake, transformation and potential risk posed by As contaminated rice. In this study we report on the distribution and chemical-speciation of As in rice (Oryza sativa Quest) by X-ray fluorescence (XRF) and X-ray absorption near edge structure (XANES) measurements of rice plants grown in As contaminated paddy water. Investigations of muXRF images from rice tissues found that As was present in all rice tissues, and its presence correlated with the presence of iron at the root surface and copper in the rice leaf. X-ray absorption near edge structure analysis of rice tissues identified that inorganic As was the predominant form of As in all rice tissues studied, and that arsenite became increasingly dominant in the aerial portion of the rice plant. PMID:19345396

  6. Comparing the costs and benefits of floating rice-based and intensive rice-based farming systems in the Mekong delta

    Directory of Open Access Journals (Sweden)

    Van Kien Nguyen

    2015-09-01

    Full Text Available This paper compares financial costs and benefits of floating rice-based and intensive rice farming systems using data from focus group discussions and household survey in four locations in the Mekong Delta. We argue that the net financial benefit per 1000m2 of integrated floating rice-based farming systems is greater than the net financial benefit of intensive rice farming system. The total net benefit of floating rice-leeks shows the highest net benefit (VND 24.8 mil./1000 m2, followed by floating rice-sweet corn- two baby corn crops and cattle systems (VND 18.5 mil./1000m2, and floating rice-chili (VND 16.7-17.7 mil./1000m2. If farmers cultivate monoculture of rice either two or three crops, the net benefits are ranging from VND 2.2-4.8 mil./1000m2 respectively. Alternatively, farmers integrate vegetables; the net benefit was ranging from VND 5.6 to 11.7 mil./1000m2. The net benefit of the two rice crops is lowest (VND 1.3-2.3 mil./1000m2. Surprisingly, if farmers convert from two intensive rice crops to two maize crops, the net benefit can reach to VND 21 million/1000m2. The results support the argument that the floating rice based systems allows farmers diversified into profitable upland crops, which can help farmers to improve their total income.

  7. 穗肥施氮量对抛栽杂交中稻抗倒伏性状和产量的影响%Effect of Amount of Panicle Fertilizer Application on Lodging Resistance and Yield of Hybrid Rice by Throwing Cultivation

    Institute of Scientific and Technical Information of China (English)

    段素梅; 杨安中; 黄义德; 沈树周

    2011-01-01

    采用大田随机区组设计研究了穗肥施氮量对徽两优2115抗倒伏性状及产量的影响.结果表明:穗肥氮肥用量对徽两优2115的株高、抗倒伏系数、产量因素及产量均有不同程度的影响.氮肥施用量以底肥(纯N)69 kg/hm.、蘖肥(纯N)69 kg/hm.、穗肥(纯N)138 kg/hm2的处理N4产量最高,较不施穗肥的对照No(ck)增产3 258.1 kg/hm2,增幅达40.7%,增产达极显著水平.%By methods of field trials and randomized blocks design, the influences of amount of panicle fertilizer application on lodging resistance and yield of hybrid rice‘ Huiliangyou 2115’ by throwing cultivation had been studied. The results indicated that amount of nitrogen fertilizer application had different effects on the plant height, the lodging resistance traits, the yield component and the production. The rice yield of N4 treatment was the highest. The yield increased by 3258.1 kg/hm2 compared with to the CK. The increase amplitude was 40.7% and reached the extreme significant level.

  8. Effects of Different Methods of Fertilizer Application and Cultivation on Ratooning Growth of Low-stubble Rice%不同施肥方式和栽培方式对低桩水稻再生生长的影响

    Institute of Scientific and Technical Information of China (English)

    黄水明

    2011-01-01

    研究采用低桩收割,在收割前后采用不同的施肥比例及收割后不同的氮肥施用量,不同的栽植方式、田间密度、丛内密度来研究施肥方式与栽培方式对水稻再生生长的影响进行了较为系统的研究。从芽苗肥配比正交实验结果表明,低桩再生稻割前可不施催芽肥而只施促苗肥,在中等地力和N:P:K固定配比为1:0.3:0.5的情况下,12kg/667m2的纯氮用量为最佳的氮肥施用量。从育秧栽植方式对有效再生率的影响实验中得出,采取盘秧抛栽方式有利于提高再生季的有效再生率。从田间密度和丛内密度对产量的影响实验得知,当田间密度在2.4万丛/667m2,每丛栽一粒谷苗时,为最佳栽培密度。%We systemically studied the effects of low stubble harvest, different fertilizer application ratios before and after the harvest and different nitrogen application rate after the harvest, different planting methods, field density, the density within the plant to study fertilization and planting methods on rice ratooning growth. The results of different bud and tiller fertilizer application ratios based on orthogonal experiment showed that low-stubble ratoon rice did not apply the fertilizer of bud promotion but only tiller fertilizer before harvest. The optimal nitrogen application rate for tiller promotion was 12kg/667m2under the medium soil fertility and the fixed N : P : K ratio of 1 : 0.3 : 0.5. The methods of seedling cultivation and field farming suggested that throwing rice seedling from plastic plate was the advantage of increasing effective ratooning tiller rate in the second crop. According to the effects of field density and the density within plant on grain yield, the optimal planting density was 24000 plant per 667m2 and one grain seedling of each plant.

  9. Effect of acetic acid on rice seeds coated with rice husk ash

    Directory of Open Access Journals (Sweden)

    Lizandro Ciciliano Tavares

    2013-06-01

    Full Text Available Flooded rice cultivation promotes anaerobic conditions, favoring the formation of short chain organic acids such as acetic acid, which may be toxic to the crop. The objective of this study was to evaluate the effect of acetic acid on rice seeds coated with rice husk ash. The experiment was arranged in a 2 x 5 x 5 factorial randomized design, with two cultivars (IRGA 424 and BRS Querência, five doses of coating material (0, 2, 3,4 e 5 g kg-1 seed and five concentrations of acetic acid (0, 3, 6, 9 and 12 mM, with 4 replications, totaling 50 treatments. The variables first count of germination, germination, shoot and root length, dry weight of shoots and roots were recorded. The results showed that coating rice seeds with rice husk ash up to 5 g kg-1 seed does not influence the performance of rice seeds of cultivars IRGA 424 and BRS Querência when exposed to concentrations of 12 mM acetic acid. The presence of acetic acid in the substrates used for seed germination reduced the vigor and viability of seeds of cultivars IRGA 424 and BRS Querência, as well as seedling development, affecting mainly the roots of BRS Querência.

  10. SUSTENTABILIDADE DE SISTEMAS ORGÂNICOS COM PLANTAS DE COBERTURA NA CULTURA DO ARROZ, POR MEIO DE ALTERAÇÕES FÍSICAS DO SOLO ORGANIC SYSTEMS SUSTAINABILITY USING COVER CROPS IN RICE CULTIVATION THROUGH SOIL PHYSICAL ATTRIBUTES CHANGES

    Directory of Open Access Journals (Sweden)

    Roberta Paula de Jesus

    2010-05-01

    ísica intermediária. A porcentagem de agregados com diâmetro maior que 2 mm e o diâmetro médio ponderado dos agregados foram maiores, independentemente de cobertura de solo, na camada 0,10-0,20 m de profundidade. Também, independentemente da cobertura de solo, o conteúdo de matéria orgânica decresceu com a profundidade do solo.

    PALAVRAS-CHAVE: Plantas de cobertura; preparo do solo; porosidade; estabilidade de agregados.

    To evaluate the influence of cover crops on Oxisol physical attributes, in an organic production system with conventional tillage, a study was conducted at Embrapa Arroz e Feijão, Santo Antônio de Goiás, Goiás State, Brazil, for two years, in a succession cover crops-rice, in which cover crops were sown in the autumn/winter and the subsequent crop, rice cultivar Aimoré, was sown in the summer. Five cover crops were used: Velvet bean (Mucuna aterrima, Sunn hemp (Crotalaria juncea, Pigeon pea (Cajanus cajan, Broom sorghum (Sorghum technicum, and spontaneous vegetation fallowing. A randomized blocks design with four replications was used. In the second year of

  11. Weed-Suppressing Effect and Mechanism of Allelopathic Rice Accessions

    Institute of Scientific and Technical Information of China (English)

    HUFei; KONGChui-hua; XUXiao-hua; ZHANGChao-xian; CHENXiong-hui

    2004-01-01

    Two allelopathic rice accessions, PI312777 and Allelopathy i, significantly suppressed the growth of associated weeds in the field. Moreover, their weed-suppressing effects were correlated with the cultivation patterns. The weed-suppressing effects of throwing and transplanting were more effective than that of direct seeding. Furthermore, the amounts of allelochemicals (resorcinols, flavones and hydroxamic acids) produced and released from two allelopathic rice accessions were much higher than that from a nonallelopathic rice variety Hua-Jing-Xian i, and reached the maximum concentration at the 6th leaf stage. Differences in the weed-suppressing effects of rice accessions appear to result from the accessions producing and releasing different amounts of allelochemicals in the field. Further research confirmed that in PI312777 plants, allelochemicals were synthesized by the above-ground parts, and then secreted through the root tissues. Root tissues of PI312777 plants never produced the allelochemicals. Root exudates from PI312777 could significantly inhibit the growth of E. crus-galli surrounding rice plants in water culture. However, when activated carbon was added to the culture solution, which could absorb allelochemicals from root exudates, the growth of E. crus-galli was no longer significantly inhibited. Weed-suppressing effects of rice accessions depended on allelopathy, cultivation patterns and other factors in rice fields, while allelopathy was one of important factors. Interestingly, the amounts of allelochemicals produced and released from allelopathic rice plants may be induced by the presence of E. crus-galli.This suggests that there is a possible chemical recognition between rice and E. crus-galli.

  12. Extensification and Intensification Process of Rainfed Lowland Rice Farming in Mozambique

    OpenAIRE

    Kajisa, Kei; Payongayong, Ellen

    2013-01-01

    This paper explores the extensification and intensification process of rice production in Mozambique’s dominant rice ecology, i.e., rainfed lowland area. Our household-level data show that the potential of extensification is not fully exploited, as only 41% of the cultivable lowland is used for rice. The lack of power predominantly constrains rice area expansion. High potential also exists in land intensification as indicated by the average yield of 2.5 t/ha among the top 25% of rainfed farme...

  13. Relationship between Living Rate of Bud and Emeraence Rate of Ratoon Rice and Characteristics of the First Cropping Mid-season Hybrid Rice

    Institute of Scientific and Technical Information of China (English)

    Lin ZHANG; Hong XIONG; Fuxian XU; Yongchuan ZHU; Xiaoyi GUO; Xingbing ZHOU; Mao LIU

    2012-01-01

    [Objective] The aim was to study the relationship of plant characters with bud living rate and mother stem emergence rate of ratoon rice before harvest. [Method] Eighteen mid-season hybrid rice cultivators approved recently were taken as materials and relationship of plant characters including bud living rate and moth- er stem emergence rate of ratoon rice before harvest was explored, based on relat- ed data. [Result] The shorter rice with lower harvesting index is the main character of high emergence rate for first cropping rice; decline of plant height and increase of ear-bearing percentage would improve emergence of regenerative seedlings. [Conclusion] The research provided scientific reference for breeding of rice cultivars with high regenerative capacity.

  14. Phospholipids in rice: significance in grain quality and health benefits: a review.

    Science.gov (United States)

    Liu, Lei; Waters, Daniel L E; Rose, Terry J; Bao, Jinsong; King, Graham J

    2013-08-15

    Phospholipids (PLs) are a major class of lipid in rice grain. Although PLs are only a minor nutrient compared to starch and protein, they may have both nutritional and functional significance. We have systemically reviewed the literature on the class, distribution and variation of PLs in rice, their relation to rice end-use quality and human health, as well as available methods for analytical profiling. Phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and their lyso forms are the major PLs in rice. The deterioration of PC in rice bran during storage was considered as a trigger for the degradation of rice lipids with associated rancid flavour in paddy and brown rice. The lyso forms in rice endosperm represent the major starch lipid, and may form inclusion complexes with amylose, affecting the physicochemical properties and digestibility of starch, and hence its cooking and eating quality. Dietary PLs have a positive impact on several human diseases and reduce the side-effects of some drugs. As rice has long been consumed as a staple food in many Asian countries, rice PLs may have significant health benefits for those populations. Rice PLs may be influenced both by genetic (G) and environmental (E) factors, and resolving G×E interactions may allow future exploitation of PL composition and content, thus boosting rice eating quality and health benefits for consumers. We have identified and summarised the different methods used for rice PL analysis, and discussed the consequences of variation in reported PL values due to inconsistencies between methods. This review enhances the understanding of the nature and importance of PLs in rice and outlines potential approaches for manipulating PLs to improve the quality of rice grain and other cereals.

  15. ECONOMIC ANALYSIS OF SMALL HOLDER RICE PRODUCTION SYSTEMS IN EBONYI STATE SOUTH EAST, NIGERIA

    Directory of Open Access Journals (Sweden)

    Nwaobiala C.U.

    2013-11-01

    Full Text Available Economic analysis of Upland and Swamp rice production in Ebonyi State, South east Nigeria was studied and analyzed in 2011 farming season. Purposive and multistage random sampling technique was used to select agricultural blocks, circles and rice farmers. The sample size was 240 rice farmers (120 Agricultural Development Programme (ADP Upland rice contact farmers and 120 Agricultural Development Programme (ADP Swamp contact rice farmers. Data for the analysis were collected from a structured questionnaire. The result indicates that mean ages of upland rice farmers was 37.3 years while swamp rice farmers had 39.2 years. The mean farming experience for both farmers were 8.5 years (upland rice farmers and 8.8 years (swamp rice farmers with farm sizes of 1.2 and 1.1 hectares for upland rice farmers and swamp rice farmers respectively. Upland rice farmers had an annual farm income of 189,410.00 NGN (1,222USD as against 201,166.00 NGN (1,297.85USD for Swamp rice farmers. The multiple regression (Cobb Douglas estimates of the determinants of output of upland rice showed that coefficients age, farming experience, farm size, variable inputs and farm income were positively signed at given levels of probability while capital inputs was negative. The Cobb Douglas regression estimates of the determinants of output of Swamp rice showed that the coefficients of education, labour cost, farm size, variable inputs and farm income were positively signed and significant at given levels of probability as well as capital inputs which was negative. The result indicates that net profit from Upland rice cultivation was 92,800.00 NGN (598.71USD with a Benefit Cost Ratio of N1.55 (1.56USD. The net profit from Swamp rice cultivation was 132,090.00 NGN (852.19USD and a Benefit Cost Ratio of 1.75 NGN (1.75USD. Access to credit to rice farmers, subsidy on farm inputs, dissemination of improved rice technologies by extension agents and formation of farmer groups were advocated

  16. Incorporation of whole, ancient grains into a modern Asian Indian diet to reduce the burden of chronic disease.

    Science.gov (United States)

    Dixit, Anjali A; Azar, Kristen Mj; Gardner, Christopher D; Palaniappan, Latha P

    2011-08-01

    Refined carbohydrates, such as white rice and white flour, are the mainstay of the modern Asian Indian diet, and may contribute to the rising incidence of type 2 diabetes and cardiovascular disease in this population. Prior to the 1950s, whole grains such as amaranth, barley, brown rice, millet, and sorghum were more commonly used in Asian Indian cooking. These grains and other non-Indian grains such as couscous, quinoa, and spelt are nutritionally advantageous and may be culturally acceptable carbohydrate substitutes for Asian Indians. This review focuses on practical recommendations for culturally sensitive carbohydrate modification in a modern Asian Indian diet to reduce type 2 diabetes and cardiovascular disease in this population. PMID:21790614

  17. Genomic variation in rice: genesis of highly polymorphic linkage blocks during domestication.

    Directory of Open Access Journals (Sweden)

    Tian Tang

    2006-11-01

    Full Text Available Genomic regions that are unusually divergent between closely related species or racial groups can be particularly informative about the process of speciation or the operation of natural selection. The two sequenced genomes of cultivated Asian rice, Oryza sativa, reveal that at least 6% of the genomes are unusually divergent. Sequencing of ten unlinked loci from the highly divergent regions consistently identified two highly divergent haplotypes with each locus in nearly complete linkage disequilibrium among 25 O. sativa cultivars and 35 lines from six wild species. The existence of two highly divergent haplotypes in high divergence regions in species from all geographical areas (Africa, Asia, and Oceania was in contrast to the low polymorphism and low linkage disequilibrium that were observed in other parts of the genome, represented by ten reference loci. While several natural processes are likely to contribute to this pattern of genomic variation, domestication may have greatly exaggerated the trend. In this hypothesis, divergent haplotypes that were adapted to different geographical and ecological environments migrated along with humans during the development of domesticated varieties. If true, these high divergence regions of the genome would be enriched for loci that contribute to the enormous range of phenotypic variation observed among domesticated breeds.

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

    Directory of Open Access Journals (Sweden)

    Ana L Caicedo

    2007-09-01

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

  19. 水稻纹枯病菌拮抗菌的筛选、鉴定及培养条件探索%Screening, Identification and Cultivation Conditions of Microbes Antagonistic to Rice Sheath Blight Fungus Rhizoctonia solani

    Institute of Scientific and Technical Information of China (English)

    曹琦琦; 周登博; 郑丽; 杨媚; 周而勋

    2013-01-01

    Three hundred and twenty five bacterial strains and eighty six actinomycete strains were isolated from the samples taken from different soils, plants and Rhizoctonia solani sclerotia. One bacterial and one actinomycete strains with strong antagonistic activities to R. solani were selected by using both agar plate dual culture and fermentation filtrate-amended medium screening methods. Their inhibition rates to mycelial growth of R. solani were 75.56% and 84.07%, respectively, on the two medial plates. Based on morphological, physiological, biochemical and molecular characteristics, NB12 was identified as Bacillus subtilis, and NA1 as Streptomyces triostinicus. The cultivation conditions for antifungal substance production by NB12 were: LB or BPY medium at initial pH 7.0, culture volume at 40 mL/250 mL flask, incubation temperature at 30 ˚C, and shaking rate at 180 r·min−1 for 48 h; whereas those for NA1 were: soybean or soybean–corn powder liquid medium at initial pH 6.0—9.0, culture volume at 130 mL/250 mL flask, incubation temperature at 35 ˚C, and shaking rate at 140 r·min−1 for 72 h or above.%  从不同土壤、植物和水稻纹枯病菌 Rhizoctonia solani 菌核样品上分离到细菌菌株325株和放线菌菌株86株。通过琼脂平板对峙法及发酵滤液介质筛选法,获得了对水稻纹枯病菌具有较强拮抗活性的细菌和放线菌菌株各1株,它们对水稻纹枯病菌菌丝生长的抑制率分别为75.56%和84.07%。采用形态学和生理生化学以及分子生物学方法,将细菌菌株 NB12鉴定为枯草芽胞杆菌 Bacillus subtilis、放线菌菌株 NA1鉴定为 Streptomyces triostinicus。对它们产生抑菌物质的发酵条件进行了探索,明确了菌株 NB12的最佳发酵条件为:初始 pH 7.0的 LB 或 BPY 培养液、装液量40 mL/250 mL、培养温度30℃、摇床转速180 r·min−1、培养时间48 h;菌株 NA1的最佳发酵条件为:初始 pH 6.0~9.0的大豆粉培养液

  20. Alternate wetting and drying in high yielding direct-seeded rice systems accomplishes multiple environmental and agronomic objectives

    Science.gov (United States)

    Rice (Oryza sativa L.) cultivation is critically important for global food security, yet it also represents a significant fraction of agricultural greenhouse gas (GHG) emissions and water resource use. Alternate wetting and drying (AWD) of rice fields has been shown to reduce both methane (CH4) emis...

  1. Development and appraisal of economical and sustainable approach for weed management in drill seeded aerobic rice (oryza sativa l.)

    International Nuclear Information System (INIS)

    Conventional rice cultivation by puddling and transplanting is a labor intensive activity. Water scarcity is a threat for the sustain ability of transplanted rice. In many areas of Asia, rice transplantation of rice is being replaced by direct seeding as farmers tried to solve the problems of labor cost and water scarcity but weed control is one of the major constraints to direct seeding. So, to control weeds in direct seeded rice present studies were designed. A two years study was conducted to develop sustainable and economical methods for managing weeds in aerobic rice grown by dry direct-seeding at Student's Farm, Department of Agronomy, University of Agriculture, Faisalabad during the years 2008 and 2009. Experiment was laid out in RCBD with five weed management strategies: hand weeding, hoeing with kasula, inter-row cultivation with tine cultivator, inter-row cultivation with spike hoe and chemical control with Nominee 100 SC along with control (no weeding). Weed dry weight was 300 g m/sup -2/, 257 g m/sup -2/, 225 g m/sup -2/ and 157 g m/sup -2/ less in hand weeding, hoeing, tine cultivator and Nominee 100 SC respectively than no weeding. Paddy yield was 221%, 203%, 181% and 105% more in hand weeding, hoeing, tine cultivator and Nominee 100 SC respectively than no weeding. (author)

  2. WTO REFORMS AND RICE MARKET IN PAKISTAN

    Directory of Open Access Journals (Sweden)

    Muhammad Bachal Jamali

    2011-10-01

    Full Text Available This research investigates the WTO reforms and Rice market in Pakistan. Data were collected from the Primary as well secondary sources of the Rice producing countries, and data were analysis by using SPSS-18 version, A structural questionnaire was developed for reliability and validity of the data. It was revealed that from the last five years there is no visible impact on export laid growth but from last three years price shocks was observed in Pakistan, due to increases in the world rice market by 200 percent in various Asian countries. Consumers are facing the price shock problem in Pakistan and world Rice market the statistical results were similar for the alternative specification of gross margins and prices as the economic decision available. However, the price elasticities derived using the gross margins specification were about a third of those using the prices specification. The gross margin specification yielded additional information in the form of yield and input cost elasticities. The analysis indicates that there are lags which are due primarily to the difficulties and cost of rapid adjustment rather than to the time required to revise expectations. The statistical results were similar for the alternative specification of gross margins and prices as the economic decision available. However, the price elasticities derived using the gross margins additional information in the form of yield and input cost elasticities

  3. Remote sensing based change analysis of rice environments in Odisha, India.

    Science.gov (United States)

    Gumma, Murali Krishna; Mohanty, Samarendu; Nelson, Andrew; Arnel, Rala; Mohammed, Irshad A; Das, Satya Ranjan

    2015-01-15

    The rainfed rice-growing environment is perhaps one of the most vulnerable to water stress such as drought and floods. It is important to determine the spatial extent of the stress-prone areas to effectively and efficiently promote proper technologies (e.g., stress-tolerant varieties) to tackle the problem of sustainable food production. This study was conducted in Odisha state located in eastern India. Odisha is predominantly a rainfed rice ecosystem (71% rainfed and 29% canal irrigated during kharif-monsoon season), where rice is the major crop and staple food of the people. However, rice productivity in Odisha is one of the lowest in India and a significant decline (9%) in rice cultivated area was observed in 2002 (a drought year). The present study analyzed the temporal rice cropping pattern in various ecosystems and identified the stress-prone areas due to submergence (flooding) and water shortage. The spatial distribution of rice areas was mapped using MODIS (MOD09Q1) 250-m 8-day time-series data (2000-2010) and spectral matching techniques. The mapped rice areas were strongly correlated (R(2) = 90%) with district-level statistics. Also the class accuracy based on field-plot data was 84.8%. The area under the rainfed rice ecosystem continues to dominate, recording the largest share among rice classes across all the years. The use of remote-sensing techniques is rapid, cost-effective, and reliable to monitor changes in rice cultivated area over long periods of time and estimate the reduction in area cultivated due to abiotic stress such as water stress and submergence. Agricultural research institutes and line departments in the government can use these techniques for better planning, regular monitoring of land-use changes, and dissemination of appropriate technologies.

  4. Asian American-Pacific American Relations: The Asian American Perspective.

    Science.gov (United States)

    Chan, Sucheng

    This paper examines the migration and settlement history of Asians into the United States and the interaction of the major Asian immigrants with each other and with American society. An important thesis is that, because the differences between Asian Americans and Pacific Islanders are much greater than the similarities between them, they should no…

  5. Special rice in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Mingshui Rice: It originated from Zhangqiu County, Shandong Province. The characteristics of Mingshui Rice were: absorbing more water, swelling up greatly after being soaked, and being sticky and smelling fragrant after cooked.

  6. Cutaneous Melanoma in Asians.

    Science.gov (United States)

    Kim, Sang Yub; Yun, Sook Jung

    2016-09-01

    Malignant melanoma is a rare disease in Asians but potentially the most aggressive form of skin cancer worldwide. It can occur in any melanocyte-containing anatomic site. Four main cutaneous melanoma subtypes are recognized: lentigo maligna melanoma, superficial spreading melanoma, acral lentiginous melanoma (ALM), and nodular melanoma. Generally, excessive exposure to ultraviolet (UV) radiation increases the risk of melanoma. The exception is ALM, which is the most common melanoma subtype in Asians and is not associated with UV radiation. ALM presents as dark brownish to black, irregular maculopatches, nodules, or ulcers on the palms, soles, and nails. The lesions may be misdiagnosed as more benign lesions, such as warts, ulcers, hematomas, foreign bodies, or fungal infections, especially in amelanotic acral melanomas where black pigments are absent. The aim of this brief review is to improve understanding and the rate of early detection thereby reducing mortality, especially regarding cutaneous melanoma in Asians. PMID:27689028

  7. Mapping paddy rice distribution using multi-temporal Landsat imagery in the Sanjiang Plain, northeast China

    Science.gov (United States)

    Jin, Cui; Xiao, Xiangming; Dong, Jinwei; Qin, Yuanwei; Wang, Zongming

    2016-03-01

    Information of paddy rice distribution is essential for food production and methane emission calculation. Phenology-based algorithms have been utilized in the mapping of paddy rice fields by identifying the unique flooding and seedling transplanting phases using multi-temporal moderate resolution (500 m to 1 km) images. In this study, we developed simple algorithms to identify paddy rice at a fine resolution at the regional scale using multi-temporal Landsat imagery. Sixteen Landsat images from 2010-2012 were used to generate the 30 m paddy rice map in the Sanjiang Plain, northeast China—one of the major paddy rice cultivation regions in China. Three vegetation indices, Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Land Surface Water Index (LSWI), were used to identify rice fields during the flooding/transplanting and ripening phases. The user and producer accuracies of paddy rice on the resultant Landsat-based paddy rice map were 90% and 94%, respectively. The Landsat-based paddy rice map was an improvement over the paddy rice layer on the National Land Cover Dataset, which was generated through visual interpretation and digitalization on the fine-resolution images. The agricultural census data substantially underreported paddy rice area, raising serious concern about its use for studies on food security.

  8. Genetic Diversity and Relationship of Weedy Rice in Taizhou City,Jiangsu Province, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Juan; Nilda R. BURGOS; MA Kun; ZHOU Yong-jun; GENG Rui-mei; YU Liu-qing

    2008-01-01

    Microsatellite markers and morphological charactedstics were used to explore the genetic diversity and possible origin of weedy dce in Taizhou City, Jiangsu Province, China. Fifty-two weedy rice (Oryza sativa L.) accessions were compared with two wild rice, four hybdd rice and five cultivars using 22 simple sequence repeat (SSR) primer pairs. A total of 107 fragments were amplified, averaging 5.6 alleles per primer pair. The polymorphic index content (PIC) values ranged from 0.3077 to 0.7951, averaging at 0.5870. The average genetic distance of all samples ranged from 0.02 to 0.46 with an average of 0.262. The genetic distance among Taizhou weedy rice ranged from 0.03 to 0.44 with an average of 0.224. Cluster analysis showed that all the weedy rice accessions from Taizhou City were indica, and could be subdivided into different genotypes. The majority (86%) of weedy rice was most closely related to hybrid rice. The Taizhou weedy dce accessions were morphologically similar, but still could be delineated into indica or japonica group by some morphological traits. it is suggested that the levels of genetic and morphological diversities of weedy rice in Taizhou City are low and these weedy rice plants originated from the segregating progenies of hybrid rice that had naturally introgressed with cultivated rice.

  9. Economic Analysis of Paddy Rice Production in Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    Kadiri, F. A.

    2014-12-01

    Full Text Available The study examined economic analysis of paddy rice production in Niger Delta Region of Nigeria in view to determine how profitable the crop is in the study area and how inputs or resources used in paddy rice production significantly affect the crop’s production. The data for the study was collected from 300 rice farmers in three out of nine states in the region based on their intensity in rice production in the study area using multistage and simple random sampling technique. Data analysis was carried out using descriptive statistics, multiple regression model and profitability model. Rice production was found to be profitable as farmers realized ₦300,071.84 as Net farm Income. It was also found that resources used in paddy rice production significantly affect paddy rice production. The result indicated that mean age of paddy rice farmers was 49 years, the mean farming experience was 17 years while mean cultivated land was 2.32 hectares It was recommended that Reviewing the Land Use Act of 1990 is critical so that most of the fertile land held by government will be released to rice farmers, also providing skilled labour required in rice production and easy evacuation of farm produce will go a long way in increasing the production of paddy rice in the study area.

  10. Mapping paddy rice distribution using multi-temporal Landsat imagery in the Sanjiang Plain, northeast China

    Institute of Scientific and Technical Information of China (English)

    Cui JIN; Xiangming XIAO; Jinwei DONG; Yuanwei QIN; Zongming WANG

    2016-01-01

    Information of paddy rice distribution is essential for food production and methane emission calculation.Phenology-based algorithms have been utilized in the mapping of paddy rice fields by identifying the unique flooding and seedling transplanting phases using multi-temporal moderate resolution (500m to 1 km) images.In this study,we developed simple algorithms to identify paddy rice at a fine resolution at the regional scale using multi-temporal Landsat imagery.Sixteen Landsat images from 2010-2012 were used to generate the 30 m paddy rice map in the Sanjiang Plain,northeast China—one of the major paddy rice cultivation regions in China.Three vegetation indices,Normalized Difference Vegetation Index (NDVI),Enhanced Vegetation Index (EVI),and Land Surface Water Index (LSWI),were used to identify rice fields during the flooding/transplanting and ripening phases.The user and producer accuracies of paddy rice on the resultant Landsat-based paddy rice map were 90% and 94%,respectively.The Landsat-based paddy rice map was an improvement over the paddy rice layer on the National Land Cover Dataset,which was generated through visual interpretation and digitalization on the fine-resolution images.The agricultural census data substantially underreported paddy rice area,raising serious concern about its use for studies on food security.

  11. Spirulina cultivation in China

    Science.gov (United States)

    Wu, Bo-Tang; Xiang, Wen-Zhou; Zeng, Cheng-Kui

    1998-03-01

    This paper reviews and discusses the development and many problems of Spirulina cultivation in China, points out the advantages and disadvantages of open photobioreactor system, and predicts that seawater Spirulina cultivation will be a new trend to be strengthened and emphasized due to its special physiological characteristics, easier management, lower fertilizer cost, and higher resistance to contaminants and rare pollution of chemicals.

  12. Methane efflux in rice paddy field under different irrigation managements

    Directory of Open Access Journals (Sweden)

    Diovane Freire Moterle

    2013-04-01

    Full Text Available Paddy rice fields may contribute to methane (CH4 emission from soil due to anaerobic conditions after flooding. Alternatives to continuous flooding irrigation in rice have been developed to mitigate CH4 efflux into the atmosphere. This study aims to investigate the effects of irrigation managements in the CH4 efflux during the rice growing season. An experiment was carried out at in Santa Maria, Rio Grande do Sul State, Brazil, during 2007/08 and 2009/10 growing seasons. The treatments were continuous flooding and intermittent irrigation in 2007/08 and continuous flooding, intermittent irrigation and flush irrigation in 2009/10. Intermittent irrigation is effective in mitigating CH4 efflux from rice fields when climatic conditions enable water absence during cultivation, but its efficiency depends on the electrochemical soil conditions during the flooding cycles.

  13. Determination of pesticide residues in river water and river sediment by LC-MS/MS and survey of contamination status in rice cultivation areas in Jiangsu province%河水及淤泥中农药残留的液质联用检测及江苏稻田区污染现状

    Institute of Scientific and Technical Information of China (English)

    沈燕; 王冬兰; 孙星; 刘贤进

    2012-01-01

    采集江苏稻田种植区872份河水和近河淤泥样品,分析稻田常用农药对河水污染现状,建立丙溴磷、三唑磷、丙环唑和咪鲜胺液质联用检测方法.河水样品经饱和氯化钠溶液和二氯甲烷+丙酮混合溶液萃取,淤泥样品经无水硫酸钠+己烷混合溶液提取,C18反相色谱柱分离,三重串联四极杆质谱仪检测.结果表明:建立的液相色谱质谱联用仪检测方法对丙溴磷、三唑磷和丙环唑在河水和淤泥中的检测限均为0.001 5 mg·kg-1,定量限均为0.005 mg·kg-1.咪鲜胺在河水和淤泥中的检测限均为0.003 mg· kg-1,定量限均为0.010 mg·kg-1.各农药在0.01~1.0 μg·mL-1范围内与响应值线性相关,决定系数均在0.99以上.对丙溴磷、三唑磷和丙环唑在河水和淤泥中分别添加0.005、0.05和0.5 mg· kg-1 3个水平,对咪鲜胺在河水和淤泥中分别添加0.01、0.1和1.0 mg· kg-1 3个水平,结果表明,平均回收率为80%~110%,相对标准偏差均在20%以内.对江苏稻田种植区河水及淤泥样品进行分析,河水中丙溴磷、三唑磷和咪鲜胺检出率分别为3.7%、1.7%和2.5%,淤泥中三唑磷检出率为1.4%,表明河水污染程度高于淤泥.试验建立的方法简便、快速,且灵敏度、准确度高、精密度好,符合农药残留检测规范要求,适用于高通量农药残留检测.%In order to survey the contamination status of rivers by common pesticides used in rice, we analyzed 872 water and soil samples from rivers in rice cultivation areas in Jiangsu province. The water samples were extracted by sodium chloride solution and the mixture of methylene dichloride+acetone, the soil samples by anhydrous sodium sulfate, sodium chloride and the mixture of acetone+n-hexane. The extractions were dried by the stream of nitrogen, separated by the reverse phase column C18, and then detected by liquid chromatography tandem mass spectrometry (LC-MS/MS). The results showed that

  14. Current Update in Asian Rhinoplasty

    OpenAIRE

    Clyde H. Ishii, MD, FACS

    2014-01-01

    Summary: There has been a tremendous growth of cosmetic surgery among Asians worldwide. Rhinoplasty is second only to blepharoplasty in terms of popularity among Asians regarding cosmetic surgical procedures. Most Asians seek to improve their appearance while maintaining the essential features of their ethnicity. There are considerable ethnic nasal and facial variations in this population alone. Successful rhinoplasty in Asians must take into account underlying anatomic differences between As...

  15. Effects of Mulching Mode on Canopy Physiological, Ecological Characteristics and Yield of Upland Rice

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-zhu; LIU Yang; ZENG Xiang; CHEN Kai-lin; HUANG Zc-hui; XIE Hong-ke

    2011-01-01

    The effects of mulching mode on population physiology and ecology of rice were studied using a combination P88S/1128 as the material under three mulching cultivation modes including plastic film mulching,straw mulching and liquid film mulching,as well as bare cultivation (control).The results indicated that mulching mode had significant effects on micro-meteorological factors and individual growth of rice,as shown by an increase of relative humidity,a better internal micro-meteorological environment of rice population,a significant reduction under the rice canopy temperature,especially during high-temperature periods.Rice plants under mulching cultivation conditions displayed a stronger transpiration and lower leaf temperature,thereby improving the ability of anti-high temperature stress and markedly increasing the photosynthetic rate.Furthermore,the yield components of rice were significantly optimized under mulching cultivation,of which with plastic film mulching displayed the highest grain number per panicle and seed-setting rate,and a yield increase of 16.81% compared with the control; and with straw mulching displayed an increase of effective panicle number and a 9.59%increase of total yield compared to the control.

  16. IMPACT OF MARKET-DETERMINED EXCHANGE RATES ON RICE PRODUCTION AND IMPORT IN NIGERIA

    Directory of Open Access Journals (Sweden)

    Aliyu Aishat Ammani

    2013-10-01

    Full Text Available Rice is an economically important food security crop, cultivated in almost all of Nigeria’s 36 States. Nigeria spends more than 356 billion naira (2.24 billion US dollars annually on rice import. This paper set out to analyze the trend in rice production, productivity, import, value of import and consumption that follows the adoption of the Structural Adjustment Programme (SAP in Nigeria, with emphasis on the effects of exchange rate (ER deregulation on domestic rice production and rice imports over the period 1986-2010. Relevant time series data were collected and used. A semi-log growth rate model and 2simple linear regression models were developed and estimated. Highlights of the findings include (i accelerated rate of growth in rice production (Instantaneous Growth Rate (IGR 2.2%; Cumulative Growth Rate (CGR 2.2%; rice hectarage (IGR 3.7%; CGR 3.8%; rice importation (IGR 8.5%; CGR8.9%; expenditure on rice importation (IGR 10.6%; CGR 11.2% and rice consumption (IGR 3.4%; CGR 3.5% alongside a significant deceleration in rice yield (IGR -1.4%; CGR -201.4% (ii The observed significant increase in domestic rice production cannot be confidently attributed to ER deregulation alone because it does not lead to a decrease in rice importation into Nigeria. (iii The significant increase in domestic rice importation as observed contradicts a priori expectation that ER deregulation will lead to significant decrease in rice importation. The study concluded that free market approach alone cannot stimulate local agricultural production in countries where farmers producing under low-technology-agriculture are put in direct competition with farmers from advancedtechnology-agriculture; hence governments need to restrict importation to protect local producers.

  17. CFD Analysis of Bubbling Fluidized Bed Using Rice Husk

    Science.gov (United States)

    Singh, Ravi Inder; Mohapatra, S. K.; Gangacharyulu, D.

    Rice is Cultivated in all the main regions of world. The worldwide annual rice production could be 666million tons (www.monstersandcritics.com,2008) for year 2008. The annual production of rice husk is 133.2 million tons considering rice husk being 20% of total paddy production. The average annual energy potential is 1.998 *1012 MJ of rice husk considering 15MJ/kg of rice husk. India has vast resource of rice husk; a renewable source of fuel, which if used effectively would reduce the rate of depletion of fossil energy resources. As a result a new thrust on research and development in boilers bases on rice husk is given to commercialize the concept. CFD is the analysis of systems involving fluid flow, heat transfer and associated phenomena such as chemical reactions by means of computer-based simulation. High quality Computational Fluid dynamics (CFD) is an effective engineering tool for Power Engineering Industry. It can determine detailed flow distributions, temperatures, and pollutant concentrations with excellent accuracy, and without excessive effort by the software user. In the other words it is the science of predicting fluid flow, heat and mass transfer, chemical reactions and related phenomena; and an innovate strategy to conform to regulations and yet stay ahead in today's competitive power market. This paper is divided into two parts; in first part review of CFD applied to the various types of boilers based on biomass fuels/alternative fuels is presented. In second part CFD analysis of fluidized bed boilers based on rice husk considering the rice husk based furnace has been discussed. The eulerian multiphase model has used for fluidized bed. Fluidized bed has been modeled using Fluent 6.2 commercial code. The effect of numerical influence of bed superheater tubes has also been discussed.

  18. Establishment of a high efficiency Agrobacterium-mediated transformation system of rice (Oryza sativa L.).

    Science.gov (United States)

    Ozawa, Kenjirou

    2009-04-01

    Technologies for transformation of rice have been developed to meet the requirements of functional genomics in order to enable the production of transgenic rice plants with useful agricultural characters. However, many rice varieties are not efficiently transformed by Agrobacterium. We have succeeded in establishing a highly efficient transformation system in rice by co-cultivating rice calli with Agrobacterium on three filter papers moistened with enriched N6 or DKN media instead of using solid media. Rice calli immersed in Agrobacterium suspension (EHA101, Agrobacterium concentration of OD600=0.04) were co-cultured on three pieces of filter paper (9cm in diameter) moistened with 5.5mL of N6 or DKN liquid co-cultivation medium supplemented with 2,4-d (2mg/L), proline (10mM), casein hydrolysate (300mg/L), sucrose (30g/L), glucose (5g/L), l-cysteine (100mg/L) and acetosyringone (15mg/L) at 25°C for 3 days in the dark. Compared with the transformation efficiency of calli co-cultivated on solid media, transformation efficiency was increased by about fivefold by using the filter paper method for many varieties of rice, including those that previously yielded much poor transformation rates.

  19. Special rice in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Wushan Rice: It grew in hilly land around Wu Mountain in Wang City, Hunan Province. Its grain is bright and transparent, and the cooked rice is soft, sticky, fragrant, and sweet in taste. It was a "Tribute Rice" in old time. Indian Indica: Growing in Wuchang City, Hubei Province, it was also called" Red Flower Rice" . It was characterized by its thin pericarp and soft, sticky, and oily quality. Its taste was delicious. Fragrant Rice 1: It was from Xinxiang and Hui counties, Henan Province. Its characteristics were: long-round in grain shape, white in color, soft and sticky in quality, and agreeable to the taste. It was usually used as a gift in the local. Baiyutang Rice: It originated from Gaozhuang Village, Beijing suburban district. It had good quality due to the irrigation of the spring water. The rice had even grain shape, white color, hard enough quality to be cooked, fragrant and sweet taste. It was one of the "Tribute Rice" in old time. Tian′e Indica Rice: Xianning and Wuchang counties, Hubei Province were its growing area. It also called "Double Grain" because of its big grain. The hull was red, while the grain was white. When cooked, it needed more water than normal rice, and the rice was agreeable to the taste. Baiyan Rice: It originated from Jishou County, Hunan Province. The grain was even in shape, white in color, and sticky in quality. The rice was easy to be cooked and was fragrant and sweet in taste. It was also a " Tribute Rice" in old time. □ (To be continued) Translated by CHEN Wenhua, From "China Rice", No. 1, 1994

  20. Asian oil demand

    International Nuclear Information System (INIS)

    This conference presentation examined global oil market development and the role of Asian demand. It discussed plateau change versus cyclical movement in the global oil market; supply and demand issues of OPEC and non-OPEC oil; if high oil prices reduce demand; and the Asian oil picture in the global context. Asian oil demand has accounted for about 50 per cent of the global incremental oil market growth. The presentation provided data charts in graphical format on global and Asia-Pacific incremental oil demand from 1990-2005; Asia oil demand growth for selected nations; real GDP growth in selected Asian countries; and, Asia-Pacific oil production and net import requirements. It also included charts in petroleum product demand for Asia-Pacific, China, India, Japan, and South Korea. Other data charts included key indicators for China's petroleum sector; China crude production and net oil import requirements; China's imports and the share of the Middle East; China's oil exports and imports; China's crude imports by source for 2004; China's imports of main oil products for 2004; India's refining capacity; India's product balance for net-imports and net-exports; and India's trade pattern of oil products. tabs., figs

  1. Asian Americans in Transition.

    Science.gov (United States)

    Karnow, Stanley; Yoshihara, Nancy

    This booklet is a detailed primer on the Asian American experience in the United States covering history, family and acculturation, education, culture and the arts, economics, discrimination and violence, and politics. An introduction reviews some basic demographics and looks at racial issues in light of the riots in Los Angeles (California) in…

  2. Gifted Asian American Women.

    Science.gov (United States)

    Kitano, Margie K.

    1997-01-01

    Presents an analysis of personal, socialization, and structural factors affecting the lifespan achievement of 15 Asian American women identified as gifted. Their families' intense focus on educational achievement and hard work are described, and the need for better preparation to overcome obstacles in the workplace is discussed. (Author/CR)

  3. Asian Institute of Technology.

    Science.gov (United States)

    Office of Naval Research, London (England).

    The Asian Institute of Technology is a notable success for that part of the world where success is not too common. It is an excellent example of not only the initiative and organization of a technical university, but also of the success of a foreign aid program. This report gives details of this organization and accomplishments. (Author)

  4. Asian Yellow Goat Cloned

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ It was released on August 24,2005 by Prof. CHEN Dayuan (Da-Yuan Chen) from the CAS Institute of Zoology that the first success in cloning the Asian Yellow Goat by nuclear transfer had recently been achieved in east China's Shandong Province.

  5. Profile: Asian Americans

    Science.gov (United States)

    ... Program Grants Other Grants Planning and Evaluation Grantee Best Practices Asian American Asthma Cancer Chronic Liver Disease Diabetes ... Phone: 240-453-2882 Office of Minority Health Resource Center Toll Free: 1-800-444-6472 / Fax: 301-251-2160 Email: info@minorityhealth.hhs.gov Stay Connected ... FOIA | Accessibility | Site Map | Contact Us | Viewers & Players

  6. Malaysian Cinema, Asian Film

    NARCIS (Netherlands)

    Heide, van der William

    2002-01-01

    This title series departs from traditional studies of national cinema by accentuating the intercultural and intertextual links between Malaysian films and Asian (as well as European and American) film practices. Using cross-cultural analysis, the author characterizes Malaysia as a pluralist society

  7. Asian fungal fermented food

    NARCIS (Netherlands)

    Nout, M.J.R.; Aidoo, K.E.

    2010-01-01

    In Asian countries, there is a long history of fermentation of foods and beverages. Diverse micro-organisms, including bacteria, yeasts and moulds, are used as starters, and a wide range of ingredients can be made into fermented foods. The main raw materials include cereals, leguminous seeds, vegeta

  8. Nicotianamine, a novel enhancer of rice iron bioavailability to humans.

    Directory of Open Access Journals (Sweden)

    Luqing Zheng

    Full Text Available BACKGROUND: Polished rice is a staple food for over 50% of the world's population, but contains little bioavailable iron (Fe to meet human needs. Thus, biofortifying the rice grain with novel promoters or enhancers of Fe utilization would be one of the most effective strategies to prevent the high prevalence of Fe deficiency and iron deficiency anemia in the developing world. METHODOLOGY/PRINCIPAL FINDINGS: We transformed an elite rice line cultivated in Southern China with the rice nicotianamine synthase gene (OsNAS1 fused to a rice glutelin promoter. Endosperm overexpression of OsNAS1 resulted in a significant increase in nicotianamine (NA concentrations in both unpolished and polished grain. Bioavailability of Fe from the high NA grain, as measured by ferritin synthesis in an in vitro Caco-2 cell model that simulates the human digestive system, was twice as much as that of the control line. When added at 1:1 molar ratio to ferrous Fe in the cell system, NA was twice as effective when compared to ascorbic acid (one of the most potent known enhancers of Fe bioavailability in promoting more ferritin synthesis. CONCLUSIONS: Our data demonstrated that NA is a novel and effective promoter of iron utilization. Biofortifying polished rice with this compound has great potential in combating global human iron deficiency in people dependent on rice for their sustenance.

  9. Adulteration and cultivation region identification of American ginseng using HPLC coupled with multivariate analysis

    OpenAIRE

    Yu, Chunhao; Wang, Chong-Zhi; Zhou, Chun-Jie; Wang, Bin; Han, Lide; Zhang, Chun-Feng; Wu, Xiao-hui; Yuan, Chun-Su

    2014-01-01

    American ginseng (Panax quinquefolius) is originally grown in North America. Due to price difference and supply shortage, American ginseng recently has been cultivated in northern China. Further, in the market, some Asian ginsengs are labeled as American ginseng. In this study, forty-three American ginseng samples cultivated in the USA, Canada or China were collected and 14 ginseng saponins were determined using HPLC. HPLC coupled with hierarchical cluster analysis and principal component ana...

  10. Articulating Asianness: Young Asian Dutch and non-homeland Asian popular media

    NARCIS (Netherlands)

    R.A. Kartosen; E.S.H. Tan

    2013-01-01

    This study explores Asian Dutch young people’s ethnic-cultural identification in relation to their media consumption, and specifically their consumption of popular media from Asian countries other than their country of origin. A survey was conducted among 486 Asian Dutch (18-35 years old). In concur

  11. Produtividade do arroz irrigado por aspersão em função do espaçamento e da densidade de semeadura Yield of upland rice cultivated under sprinkler irrigation as a function of row spacing and seed density

    Directory of Open Access Journals (Sweden)

    CARLOS ALEXANDRE COSTA CRUSCIOL

    2000-06-01

    Full Text Available Com o objetivo de estudar o efeito de três espaçamentos entre fileiras (30, 40 e 50 cm e três densidades de semeadura (100, 150 e 200 sementes viáveis/m² sobre o desenvolvimento da planta, os componentes da produção e a produtividade do arroz irrigado por aspersão até a tensão de reposição de água de -0,070 MPa, foi instalado um experimento em condições de campo, em um Latossolo Vermelho-Escuro, epieutrófico, textura argilosa, em Selvíria, MS. A cultivar avaliada foi a IAC 201. Esta cultivar apresenta suscetibilidade ao acamamento, no sistema de irrigação por aspersão, até uma tensão de reposição de água, no solo, de -0,070 Mpa. O número de colmos e de panículas é incrementado com a redução do espaçamento. A densidade de 100 sementes/m² é a mais indicada para a cultivar IAC 201 irrigada por aspersão, por proporcionar menor gasto de sementes. O espaçamento de 30 cm entre fileiras de plantas proporciona maior produtividade de grãos da cultivar IAC 201 no sistema de irrigação por aspersão.Plant development, plant phenology, yield components and grain yield of upland rice, cv. IAC 201, submitted to three different row spacings (30, 40 and 50 cm and densities (100, 150 and 200 viable seeds/m² were studied. The experiment was set under field conditions in a Dark-Red Latosol, loamy texture, in Selvíria, MS, Brazil, under sprinkler irrigation conditions with water replacement tension of -0.070 MPa. The number of stalks and panicles per area increased with row spacing reduction; density of 100 viable seeds/m² is more indicated for IAC 201 cultivated under sprinkler irrigation conditions, because seed spend is smaller; row spacing of 30 cm allowed the maximum grain yield.

  12. Special rice in China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Shanxi black rice It was originally from Yang County, Hanzhong Region.This rice was a world-famous rice variety developed in 140 BC. It had pitch-black surface with the protein and oil contents being 6.8% and 20% higher than that of common rice, respectively. It had 15 kinds of amino acids and many kinds of vitamins. It was praised as" Black pearl" and "The king of the world riee".DongnianThe other names for Dongnian were "Yellow rice" and "Oil rice". It was grown in E City and Huangmei County,Hubei Province. It was characterized by its long-slim shape, milky yellow in color, oily, solid, and sticky quality, fragrant smell, and easiness for digestion.Guizhou black pearl rice

  13. Overexpression of Arabidopsis and rice stress genes' inducible transcription factor confers drought and salinity tolerance to rice.

    Science.gov (United States)

    Datta, Karabi; Baisakh, Niranjan; Ganguly, Moumita; Krishnan, Sellapan; Yamaguchi Shinozaki, Kazuko; Datta, Swapan K

    2012-06-01

    Rice yield is greatly affected by environmental stresses such as drought and salinity. In response to the challenge of producing rice plants tolerant to these stresses, we introduced cDNA encoding the transcription factors DREB1A and DREB1B under the control of the stress inducible rd29 promoter. Two different indica rice cultivars were used, BR29, an improved commercially cultivated variety from Bangladesh and IR68899B, an IRRI bred maintainer line for hybrid rice. Agrobacterium mediated transformation of BR29 was done independently with DREB1A isolated from rice and Arabidopsis and DREB1B isolated from rice, whereas biolistic transformation was done with rice- DREB1B in the case of IR68899B. Initial genetic integration was confirmed by PCR and Southern blot analysis. Salinity tolerance was assayed in very young seedlings. Drought stress tests were found to be more reliable when they were carried out at the pre-flowering booting stage. RNA gel blot analysis as well as quantitative PCR analysis was performed to estimate the transcription level under stressed and unstressed conditions. Agronomic performance studies were done with stressed and unstressed plants to compare the yield losses due to dehydration and salt loading stresses. Noticeably enhanced tolerance to dehydration was observed in the plants transformed with DREB1A isolated from Arabidopsis while DREB1B was found to be more effective for salt tolerance.

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

    Science.gov (United States)

    Sha, Yuexia; Wang, Qi; Li, Yan

    2016-01-01

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

  15. A Bentazon and Sulfonylurea-sensitive Mutant in Rice and its Application in Hybrid Rice

    International Nuclear Information System (INIS)

    A rice bentazon-lethal mutant 8077S obtained by radiation, is being utilized in developing new hybrid rice systems. Genetic analysis revealed that the bentazon-lethal mutant was controlled by a single recessive gene, which is named bel. The mutant can be killed at the seedling stage by bentazon with a lethal dosage at 300 mg/l or above, while this dosage is safe for its F1 hybrids and all other normal rice. This mutant is also sensitive to all the tested sulfonylurea herbicides and this sensitivity is also controlled by bel. Interestingly, another rice bentazon-lethal mutant Norin8m also obtained by radiation in Japan, was controlled by the allelic locus of bel, which is named as bsl. These two mutant genes were cloned by map-based cloning. Both mutant alleles had a single-base deletion respectively. There is a G deletion in the bel. and a C deletion in the bsl. The wild-type gene bel. encodes a novel cytochrome P450 monooxgenase, named CYP81A6. Otherwise, the use of photo-thermogenic male sterility (P/TGMS) system in two-line hybrid rice breeding is affected greatly by the sterility instability of P/TGMS lines caused by temperature fluctuation beyond their critical temperatures for fertility reversion. To prevent the hybrid seed contamination, we have developed three bentazon-lethal P/TGMS lines using 8077S by backcross and three new hybrid rice varieties using these P/TGMS lines had been registered. When these P/TGMS lines selfed by temperature fluctuation, the seedlings from the selfed seeds can be killed by spraying bentazon at seedling stage but the hybrid seedlings are safety. These new hybrid rice varieties have been cultivated in five provinces in China. (author)

  16. Occurrence and function of yeasts in Asian indigenous fermented foods.

    Science.gov (United States)

    Aidoo, Kofi E; Nout, M J Rob; Sarkar, Prabir K

    2006-01-01

    In the Asian region, indigenous fermented foods are important in daily life. In many of these foods, yeasts are predominant and functional during the fermentation. The diversity of foods in which yeasts predominate ranges from leavened bread-like products such as nan and idli, to alcoholic beverages such as rice and palm wines, and condiments such as papads and soy sauce. Although several products are obtained by natural fermentation, the use of traditional starter cultures is widespread. This minireview focuses on the diversity and functionality of yeasts in these products, and on opportunities for research and development. PMID:16423068

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

    Science.gov (United States)

    Dent, R G

    1982-09-01

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

  18. Impacts of irrigated rice production on the water quality of the Paraíba do Sul river - Taubaté region, SP, Brazil

    Directory of Open Access Journals (Sweden)

    José Geanini Peres

    2010-04-01

    Full Text Available The urban, industrial and agricultural growth of the cities across Taubaté region influences water quality of Paraíba do Sul river. Due to the importance for human life quality, economic development and environmental sustainability it is necessary to keep water quality control of this river. In this study, physical, chemical and biochemical attributes of rice cultivation were analyzed in the Paraiba do Sul river water in the Taubaté region. The analyses were made during the rice growing season. The results showed that the practice of rice cultivation increased the pollution level of Paraíba do Sul river. Due to rice cultivation, fertilizers and organic matter were introduced in the river waters demonstrating that fertilization practices require rigid control for wetland rice production.

  19. Title: Rice Crop Monitoring by Fusing Microwave and Optical Satellite Data

    Science.gov (United States)

    Oyoshi, K.; Takeuchi, W.; LE Toan, T.; Sobue, S.

    2015-12-01

    Rapid population and economic growth, and the increase in extreme weather events, are destabilizing global food security. In Asia, rice is a staple cereal crop, and the continent accounts for about 90% of global rice production and consumption. The Group on Earth Observations (GEO) Global Agricultural Monitoring (GLAM) was launched in 2011 to utilize remote sensing tools to enhance crop production projections in order to promote food security and foster sustainable economic growth. Asia---‒Rice Crop Estimation & Monitoring (Asia---‒RiCE) is a component of GEOGLAM, and aims to use remote sensing tools to develop rice---‒related information such as maps of paddy fields, rice growing conditions, yield, and production. However, in some regions in Southeast Asia, rice is planted and harvested more than twice a year, and the crop calendar is quite complicated. In addition, rice is mainly cultivated in the rainy season, and the high density of cloud cover during that season limits the observations that can be made from space using only optical sensors. In contrast, Synthetic Aperture Radar (SAR) is a robust tool because it penetrates cloud cover; however, the revisit frequency of a single SAR satellite is limited, making it difficult to capture the complicated rice crop calendar in Asia. In this research, time---‒series SAR data were fused with optical data to monitor rice crops in Southeast Asia with complicated crop calendars. In addition, a microwave radiometer that also penetrates clouds and has a high revisit frequency but a coarse spatial resolution (greater than several kilometers), was used. The integrated use of a large variety of satellite data enables us to periodically monitor surface conditions such as water inundation, transplanting, and rice crop growth and harvesting, which in turn enables us to examine rice planted areas, rice crop calendars, and rice growing conditions in order to estimate rice production.

  20. The Power of Inbreeding: NGS-Based GWAS of Rice Reveals Convergent Evolution during Rice Domestication.

    Science.gov (United States)

    Wang, Hongru; Xu, Xun; Vieira, Filipe Garrett; Xiao, Yunhua; Li, Zhikang; Wang, Jun; Nielsen, Rasmus; Chu, Chengcai

    2016-07-01

    Low-coverage whole-genome sequencing is an effective strategy for genome-wide association studies in humans, due to the availability of large reference panels for genotype imputation. However, it is unclear whether this strategy can be utilized in other species without reference panels. Using simulations, we show that this approach is even more relevant in inbred species such as rice (Oryza sativa L.), which are effectively haploid, allowing easy haplotype construction and imputation-based genotype calling, even without the availability of large reference panels. We sequenced 203 rice varieties with well-characterized phenotypes from the United States Department of Agriculture Rice Mini-Core Collection at an average depth of 1.5× and used the data for mapping three traits. For the first two traits, amylose content and seed length, our approach leads to direct identification of the previously identified causal SNPs in the major-effect loci. For the third trait, pericarp color, an important trait underwent selection during domestication, we identified a new major-effect locus. Although known loci can explain color variation in the varieties of two main subspecies of Asian domesticated rice, japonica and indica, the new locus identified is unique to another domesticated rice subgroup, aus, and together with existing loci, can fully explain the major variation in pericarp color in aus. Our discovery of a unique genetic basis of white pericarp in aus provides an example of convergent evolution during rice domestication and suggests that aus may have a domestication history independent of japonica and indica.

  1. The Power of Inbreeding: NGS-Based GWAS of Rice Reveals Convergent Evolution during Rice Domestication.

    Science.gov (United States)

    Wang, Hongru; Xu, Xun; Vieira, Filipe Garrett; Xiao, Yunhua; Li, Zhikang; Wang, Jun; Nielsen, Rasmus; Chu, Chengcai

    2016-07-01

    Low-coverage whole-genome sequencing is an effective strategy for genome-wide association studies in humans, due to the availability of large reference panels for genotype imputation. However, it is unclear whether this strategy can be utilized in other species without reference panels. Using simulations, we show that this approach is even more relevant in inbred species such as rice (Oryza sativa L.), which are effectively haploid, allowing easy haplotype construction and imputation-based genotype calling, even without the availability of large reference panels. We sequenced 203 rice varieties with well-characterized phenotypes from the United States Department of Agriculture Rice Mini-Core Collection at an average depth of 1.5× and used the data for mapping three traits. For the first two traits, amylose content and seed length, our approach leads to direct identification of the previously identified causal SNPs in the major-effect loci. For the third trait, pericarp color, an important trait underwent selection during domestication, we identified a new major-effect locus. Although known loci can explain color variation in the varieties of two main subspecies of Asian domesticated rice, japonica and indica, the new locus identified is unique to another domesticated rice subgroup, aus, and together with existing loci, can fully explain the major variation in pericarp color in aus. Our discovery of a unique genetic basis of white pericarp in aus provides an example of convergent evolution during rice domestication and suggests that aus may have a domestication history independent of japonica and indica. PMID:27179918

  2. Potential of rice straw for bio-refining: An overview.

    Science.gov (United States)

    Abraham, Amith; Mathew, Anil Kuruvilla; Sindhu, Raveendran; Pandey, Ashok; Binod, Parameswaran

    2016-09-01

    The biorefinery approach for the production of fuels and chemicals is gaining more and more attraction in recent years. The major advantages of biorefineries are the generation of multiple products with complete utilization of biomass with zero waste generation. Moreover the process will be economically viable when it targets low volume high value products in addition to high volume low value products like bioethanol. The present review discuss about the potential of rice straw based biorefinery. Since rice is a major staple food for many Asian countries, the utilization of the rice straw residue for fuel and chemicals would be very economical. The review focuses the availability and the potential of this residue for the production of fuel and other high value chemicals. PMID:27067674

  3. GIS-based climatic regionalization of ratoon rice in Chongqing area

    Science.gov (United States)

    gao, Yanghua; Chen, Zhijun; Yang, Shiqi; Tang, Yunhui; Yuan, Deshen

    2010-07-01

    According to ratoon rice growth and yield formation with meteorological conditions, the paper analyzed the main climatic factors which influence the growth of ratoon rice, and determined the accumulated temperature and sunshine duration of the key period as the index of climatic regionalization. The fine spatial distribution of ratoon rice regionalization was made based on the spatial distribution of indexes which was made based on the GIS and 1:250,000 DEM. And then the paper reviewed the characteristics of various types of regional climate resources separately and put forward proposals in allusion to the cultivation based on the coordinated development between the ratoon rice and other crops in late autumn, the development of annual planting plan and cultivation methods.

  4. Asian Media Productions

    DEFF Research Database (Denmark)

    This work consists of 12 essays on different aspects of Asian media by Japanese, European, and American scholars, many of whom have themselves been involved in the production of media forms. Working in the fields of anthropology, media and cultural studies, and on the basis of hands-on research, ......, they have written a book on the social practices and cultural attitudes of people producing, reading, watching and listening to different kinds of media in Japan, China, Taiwan, Indonesia, Vietnam, Singapore and India.......This work consists of 12 essays on different aspects of Asian media by Japanese, European, and American scholars, many of whom have themselves been involved in the production of media forms. Working in the fields of anthropology, media and cultural studies, and on the basis of hands-on research...

  5. A Methodological Investigation of Cultivation.

    Science.gov (United States)

    Rubin, Alan M.; And Others

    Cultivation theory states that television engenders negative emotions in heavy viewers. Noting that cultivation methodology contains an apparent response bias, a study examined relationships between television exposure and positive restatements of cultivation concepts and tested a more instrumental media uses and effects model. Cultivation was…

  6. Is Asian Currency Unit Attractive to East Asian Economies?

    Institute of Scientific and Technical Information of China (English)

    Bin Zhang; Fan He

    2007-01-01

    Pegging the RMB exchange rate to the Asian currency unit (ACU) has not, at least in the short term, been proved a better solution than pegging to the US dollar or pegging to a G-3 (US$, Japaneseyen and euro) currency basket. Although the Asian currency unit can help Asian economies to keep the relative price of regional currencies stable, the cost of joining a formal regional monetary cooperation is the relinquishment of the autonomy of their domestic policies. Asian monetary cooperation needs to provide more potential benefits if it is to attract Asian economies. We argue that Asian monetary cooperation should be designed to solve the problem of regional trade imbalance, and regional exchange rate policy coordination should be adopted as the first step towards exchange rate cooperation.

  7. Rice that Filipinos Grow and Eat

    OpenAIRE

    de Leon, John C.

    2005-01-01

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

  8. Asian American Adolescent Identity

    OpenAIRE

    Ohm, Julie Juhye

    1999-01-01

    The formation of ego identity in Asian American late adolescents attending Virginia Tech was examined within the frameworks of Erikson's psychosocial theory and Berry, Trimble, and Olmedo's model of acculturation. Ego identity was measured using the Achieved sub-scale of the Revised Version of the Extended Objective Measure of Ego Identity Status, an instrument based on the theoretical constructs of Erikson. Ethnic identity was measured using the Multigroup Ethnic Identity Measure and Ameri...

  9. Asian material culture

    OpenAIRE

    2009-01-01

    This exciting, richly illustrated volume gives the reader a unique insight into the materiality of Asian cultures and the ways in which objects and practices can simultaneously embody and exhibit aesthetic and functional characteristics, everyday and spiritual aspirations. Material culture is examined from a variety of perspectives and the authors rigorously investigate the creation and meaning of material object, and their associated practices within the context of time and place. All chapte...

  10. 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...

  11. Research on genetics of rice heading date

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Heading date is one of the most important traits for rice adaptation to cultivation area and crop seasons, and it is mainly determined by photoperiod, basic vegetative growth, and temperature of cultivars. The diversity of combinations of photo-sensitive varieties and the basic vegetative, makes the heading date varied. On one hand, this supplies abundant resources for different ecotypes breeding; on the other hand, it complicates the inheritance of heading date. In recent years, transgression of late maturity has often been encountered, especially between indica and japonica subspecies, this had inhabited the use of hybrid vigor. Therefore, understanding the inheritance basis of heading date is very important for breeding practices.

  12. The impact of wood biochar as a soil amendment in aerobic rice systems of the Brazilian Savannah

    OpenAIRE

    Carvalho, M.T.M.

    2015-01-01

    Abstract Keywords: tropical Savannah, biochar, soil fertility, aerobic rice, grain yield, N2O emission Márcia Thaís de Melo Carvalho (2015). The impact of wood biochar as a soil amendment in aerobic rice systems of the Brazilian Savannah. PhD thesis, Wageningen University, The Netherlands, with summaries in English, Dutch and Portuguese,  160 pp. Rice is a staple food for 3 billion people in the world. In Brazil, rice is a traditional staple food mostly cultivated by smallh...

  13. Comparative metabolomic analysis reveals a reactive oxygen species-dominated dynamic model underlying chilling environment adaptation and tolerance in rice.

    Science.gov (United States)

    Zhang, Jingyu; Luo, Wei; Zhao, Yuan; Xu, Yunyuan; Song, Shuhui; Chong, Kang

    2016-09-01

    Cold, a major environmental stress for plants, has been studied intensively for decades. Its response system has been revealed, especially at the transcriptional level. The mechanisms underlying recovery growth and environmental adaptation, however, remain unknown. Taking advantage of a naturally existing system, two subspecies of Asian cultivated rice (Oryza sativa) with significant divergence in chilling tolerance, we analyzed representative japonica and indica varieties, Nipponbare and 93-11, using comparative metabolomic analysis at six time points covering chilling treatment and recovery. In total, 223 known metabolites were detected. During chilling treatment, significant biochemical changes were centered on antioxidation. During recovery, a wide-ranging chilling response was observed. Large-scale amino acid accumulation occurred, consistent with the appearance of chilling injury. At the mid-treatment stage, the accumulation of antioxidation-related compounds appeared earlier in Nipponbare than in 93-11, consistent with the higher reactive oxygen species (ROS) levels in japonica vs indica varieties. A significant contribution of ROS-mediated gene regulation, rather than the C-repeat binding factor/dehydration-responsive-element binding factor (CBF/DREB) regulon, to the more vigorous transcriptional stress response in Nipponbare was revealed by RNA-seq. Accordingly, during recovery, the induction of stress-tolerant-related metabolites was more active in the chilling-tolerant variety Nipponbare. Senescence-related compounds accumulated only in the chilling-sensitive variety 93-11. Our study uncovers the dynamic metabolic models underlying chilling response and recovery, and reveals a ROS-dominated rice adaptation mechanism to low-temperature environments. PMID:27198693

  14. Remote Sensing Based Methane Emission Inventory Vis-A-Vis Rice Cultural Types Of South Asia

    OpenAIRE

    Manjunath, K. R.; More, R.; P. Chauhan; Vyas, A.; S. Panigrahy; Parihar, J. S.

    2014-01-01

    Rice cultivation has been recognized as one of the major anthropogenic source for methane (CH4) emissions which is a microbial mediated anaerobic activity, mainly favoured by the flooded conditions in the rice fields. Information available on CH4 emission is limited, especially in a spatial domain, mainly because of the complexity involved in generating such data. The current approach demonstrates the use of secondary data sources available on the methane emission scaling factors, co...

  15. Prospects for Rice Yield Improvement in the Post-Green Revolution Philippines

    OpenAIRE

    P. L. Pingali; P. F. Moli; L. E. Velasco

    1990-01-01

    Evidence from farm level and experimental data from the Philippines indicates a trend towards stagnation and/or decline in irrigated rice yield when intensively cultivated, even under scientific management on experiment station. Given current rice technology, there is a minimal yield gap between the experiment station and the "best" irrigated farms in the Philippines. if the current yield frontier does not shift outwards, the long-term prospects are for stagnation and/or decline in the farm y...

  16. Development of a Remote Sensing-Based “Boro” Rice Mapping System

    OpenAIRE

    Mostafa K. Mosleh; Hassan, Quazi K.

    2014-01-01

    Rice is one of the staple foods across the world, thus information about its production is essential for ensuring food security. Here, our objective was to develop a method for mapping “boro” rice (i.e., cultivated during the months January to May) in a Bangladeshi context. In this paper, we used a Moderate Resolution Imaging Spectroradiometer (MODIS)-derived 16-day composite of normalized difference vegetation index (NDVI) at 250 m spatial resolution in conjunction with ancillary datasets (i...

  17. Rapid, small scale purification of rice hoja blanca and Echinochloa hoja blanca tenuivirus ribonucleoprotein.

    Science.gov (United States)

    de Miranda, J R; Espinoza, A M; Hull, R

    1996-01-01

    Highly purified tenuivirus ribonucleoprotein was obtained from small amounts of leaf tissue by sedimenting the ribonucleoprotein particles from debris-free plant extract into a 30% sucrose cushion, in 1.5-mL microfuge tubes. Using this protocol, significant size differences were discovered in the double-stranded forms of the viral genomic RNAs of rice hoja blanca tenuivirus and a tenuivirus isolated from Echinochloa colonum, a common weed of rice cultivation. PMID:8690758

  18. The determinants of technology adoption: a case of the rice sector in Tanzania

    OpenAIRE

    Nakano, Yuko; Kajisa, Kei

    2012-01-01

    Using an extensive household-level data set collected in Tanzania, this paper investigates the determinants of technology adoption in rice cultivation by focusing on the role of credit. We find that credit enhances fertilizer use and the adoption of labor-intensive agronomic practices such as transplanting in rows and plot leveling. Based on these findings, we argue that with appropriate policies including credit, a rice Green Revolution can improve the productivity of small-scale farmers in ...

  19. Fusarium spp. associated with rice Bakanae: ecology, genetic diversity, pathogenicity and toxigenicity

    DEFF Research Database (Denmark)

    Wulff, E.G.; Sørensen, Jens Laurids; Lubeck, M.;

    2010-01-01

    African and Asian populations of Fusarium spp. (Gibberella fujikuroi species complex) associated with Bakanae of rice (Oryzae sativa L.) were isolated from seeds and characterized with respect to ecology, phylogenetics, pathogenicity and mycotoxin production. Independent of the origin, Fusarium spp....... were detected in the different rice seed samples with infection rate ranges that varied from 0.25% to 9%. Four Fusaria (F. andiyazi, F. fujikuroi, F. proliferatum and F. verticillioides) were found associated with Bakanae of rice. While three of the Fusaria were found in both African and Asian seed...... samples, F. fujikuroi was only detected in seed samples from Asia. Phylogenetic studies showed a broad genetic variation among the strains that were distributed into four different genetic clades. Pathogenicity tests showed that all strains reduced seed germination and possessed varying ability to cause...

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

    Science.gov (United States)

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

    2015-01-01

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

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

    OpenAIRE

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

    2015-01-01

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

  2. In Vivo Hypocholesterolemic Effect of MARDI Fermented Red Yeast Rice Water Extract in High Cholesterol Diet Fed Mice

    OpenAIRE

    Swee Keong Yeap; Boon Kee Beh; Joan Kong; Wan Yong Ho; Hamidah Mohd Yusof; Nurul Elyani Mohamad; Aminuddin bin Hussin; Indu Bala Jaganath; Noorjahan Banu Alitheen; Anisah Jamaluddin; Kamariah Long

    2014-01-01

    Fermented red yeast rice has been traditionally consumed as medication in Asian cuisine. This study aimed to determine the in vivo hypocholesterolemic and antioxidant effects of fermented red yeast rice water extract produced using Malaysian Agricultural Research and Development Institute (MARDI) Monascus purpureus strains in mice fed with high cholesterol diet. Absence of monacolin-k, lower level of γ-aminobutyric acid (GABA), higher content of total amino acids, and antioxidant activities w...

  3. Integrated Physiological, Biochemical, and Molecular Analysis Identifies Important Traits and Mechanisms Associated with Differential Response of Rice Genotypes to Elevated Temperature

    OpenAIRE

    Sailaja, Boghireddy; Subrahmanyam, Desiraju; Neelamraju, Sarla; Vishnukiran, Turaga; Rao, Yadavalli Venkateswara; Vijayalakshmi, Pujarula; Voleti, Sitapati R.; Bhadana, Vijai P.; Mangrauthia, Satendra K.

    2015-01-01

    In changing climatic conditions, heat stress caused by high temperature poses a serious threat to rice cultivation. A multiple organizational analysis at physiological, biochemical, and molecular levels is required to fully understand the impact of elevated temperature in rice. This study was aimed at deciphering the elevated temperature response in 11 popular and mega rice cultivars widely grown in India. Physiological and biochemical traits specifically membrane thermostability (MTS), antio...

  4. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Forattini Oswaldo Paulo

    1994-01-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  5. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1994-10-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  6. Investigating Market Integration and Price Transmission of Different Rice Qualities in Iran

    Directory of Open Access Journals (Sweden)

    Amir Hossein Chizari

    2013-12-01

    Full Text Available Rice production in most of Asian countries has been increased more rapidly than population and this has been led to increase in supply and proportionately decrease in the real price of rice in world and domestic markets. Furthermore, together with growth in production and national gross income of the country per-capita income has been increased and also demand for rice at national and international level quality has been increased. In this case studying the market conditions of different qualities of rice including marketing margins, causative relations among the prices, market integrations in long term and finally price transferring and market integration in short term is the important consequence that can help policymakers and planners in their decision makings on research, production, distribution and marketing of rice strategic product. So, using the statistics from Jihad Agriculture Organization of Guilan Province in case of the price of rice qualities (items including Sadri momtaz (S1, Sadri darge yek (S2, Sadri mamooli (S3 and Khazar (K1 during 1999-2009 market conditions of different qualities of rice was studied. Results show that impulses in wholesale prices in Khazar rice rapidly influence on-farm prices, however, in case of other rice qualities the rate and speed of this influence is low. But in wholesale-retail market for Sadri quality rice impulses influence strongly in wholesale price and this shows intense integration of these two rice markets in Iran. It is suggested that according to the different quality of rice verities, support policy design and decision making process assigned separately

  7. Introduction and Utilization of INGER Rice Germplasm in China

    Institute of Scientific and Technical Information of China (English)

    TANGSheng-xiang; WEIXing-hua; ELJavier

    2004-01-01

    The International Network for Genetic Evaluation of Rice (INGER) is a global partnership between international and national agricultural research institutions. INGER focuses on worldwide exchange, evaluation and utilization of improved varieties and elite breeding lines of rice. China has actively participated in the activities of INGER since 1980.During the pasted years, 26 500 INGER entries with diversity genetic background have been introduced and evaluated by Chinese scientists. Among of them, 37 commercial varieties directly from elite INGER entries and 27 rice hybrids using INGER lines as their restorer lines/donors have been released to farmers in China. About 1 900 INGER entries were indirectly utilized as cross parents or pest resistant donors in various national and provincial rice breeding programs. Based on the incomplete statistics, there were 14.5 million cumulated hectares planting these varieties and hybrids, from which 5.44 MT of increased rough rice has been received by farmers. INGER accelerates the transfer of adapted varieties and hybrids to farmers, and increases the diversity of rice germplasm in cultivation. Therefore, INGER cooperation has made great benefit both in economy and society in China.

  8. Introduction and Utilization of INGER Rice Germplasm in China

    Institute of Scientific and Technical Information of China (English)

    TANG Sheng-xiang; WEI Xing-hua; E L Javier

    2004-01-01

    The International Network for Genetic Evaluation of Rice (INGER) is a global partnership between international and national agricultural research institutions. INGER focuses on worldwide exchange, evaluation and utilization of improved varieties and elite breeding lines of rice. China has actively participated in the activities of INGER since 1980.During the pasted years, 26 500 INGER entries with diversity genetic background have been introduced and evaluated by Chinese scientists. Among of them, 37 commercial varieties directly from elite INGER entries and 27 rice hybrids using INGER lines as their restorer lines/donors have been released to farmers in China. About 1 900 INGER entries were indirectly utilized as cross parents or pest resistant donors in various national and provincial rice breeding programs. Based on the incomplete statistics, there were 14.5million cumulated hectares planting these varieties and hybrids, from which 5.44 MT of increased rough rice has been received by farmers. INGER accelerates the transfer of adapted varieties and hybrids to farmers, and increases the diversity of rice germplasm in cultivation. Therefore, INGER cooperation has made great benefit both in economy and society in China.

  9. Microbial community structure in the rhizosphere of rice plants

    Directory of Open Access Journals (Sweden)

    Björn eBreidenbach

    2016-01-01

    Full Text Available The microbial community in the rhizosphere environment is critical for the health of land plants and the processing of soil organic matter. The objective of this study was to determine the extent to which rice plants shape the microbial community in rice field soil over the course of a growing season. Rice (Oryza sativa was cultivated under greenhouse conditions in rice field soil from Vercelli, Italy and the microbial community in the rhizosphere of planted soil microcosms was characterized at four plant growth stages using quantitative PCR and 16S rRNA gene pyrotag analysis and compared to that of unplanted bulk soil. The abundances of 16S rRNA genes in the rice rhizosphere were on average twice that of unplanted bulk soil, indicating a stimulation of microbial growth in the rhizosphere. Soil environment type (i.e. rhizosphere versus bulk soil had a greater effect on the community structure than did time (e.g. plant growth stage. Numerous phyla were affected by the presence of rice plants, but the strongest effects were observed for Gemmatimonadetes, Proteobacteria and Verrucomicrobia. With respect to functional groups of microorganisms, potential iron reducers (e.g. Geobacter, Anaeromyxobacter and fermenters (e.g. Clostridiaceae, Opitutaceae were notably enriched in the rhizosphere environment. A Herbaspirillum species was always more abundant in the rhizosphere than bulk soil and was enriched in the rhizosphere during the early stage of plant growth.

  10. Determinants for grading Malaysian rice

    Science.gov (United States)

    ChePa, Noraziah; Yusoff, Nooraini; Ahmad, Norhayati

    2016-08-01

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

  11. Transition in nori cultivation

    DEFF Research Database (Denmark)

    Delaney, Alyne

    2011-01-01

    undertaken in Northeastern Japan among a community of nori cultivators on their production process and cultural way of life. Natural scientists acknowledge that in order to manage natural resources, it is actually the resource users who must be managed. In order to manage resource users, with the goals...... of social and environmental sustainability, we must understand both society and cultural institutions. With this in mind, this article focuses on the division of labor among cultivators, particularly along gender lines and the impacts, on a cultural level, of technological change on nori production...

  12. Multiple loci and epistases control genetic variation for seed dormancy in weedy rice (Oryza sativa).

    OpenAIRE

    Gu, Xing-You; Kianian, Shahryar F.; Foley, Michael E.

    2004-01-01

    Weedy rice has much stronger seed dormancy than cultivated rice. A wild-like weedy strain SS18-2 was selected to investigate the genetic architecture underlying seed dormancy, a critical adaptive trait in plants. A framework genetic map covering the rice genome was constructed on the basis of 156 BC(1) [EM93-1 (nondormant breeding line)//EM93-1/SS18-2] individuals. The mapping population was replicated using a split-tiller technique to control and better estimate the environmental variation. ...

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

    Science.gov (United States)

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

    2015-01-01

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

  14. Using NOAA/AVHRR based remote sensing data and PCR method for estimation of Aus rice yield in Bangladesh

    Science.gov (United States)

    Nizamuddin, Mohammad; Akhand, Kawsar; Roytman, Leonid; Kogan, Felix; Goldberg, Mitch

    2015-06-01

    Rice is a dominant food crop of Bangladesh accounting about 75 percent of agricultural land use for rice cultivation and currently Bangladesh is the world's fourth largest rice producing country. Rice provides about two-third of total calorie supply and about one-half of the agricultural GDP and one-sixth of the national income in Bangladesh. Aus is one of the main rice varieties in Bangladesh. Crop production, especially rice, the main food staple, is the most susceptible to climate change and variability. Any change in climate will, thus, increase uncertainty regarding rice production as climate is major cause year-to-year variability in rice productivity. This paper shows the application of remote sensing data for estimating Aus rice yield in Bangladesh using official statistics of rice yield with real time acquired satellite data from Advanced Very High Resolution Radiometer (AVHRR) sensor and Principal Component Regression (PCR) method was used to construct a model. The simulated result was compared with official agricultural statistics showing that the error of estimation of Aus rice yield was less than 10%. Remote sensing, therefore, is a valuable tool for estimating crop yields well in advance of harvest, and at a low cost.

  15. Factors affecting the income from major crops in rice-wheat ecological zone

    International Nuclear Information System (INIS)

    Agriculture is an important sector of our economy. About twenty-two percent of national income and 44.8 percent of total employment is generated by this sector. About 66 percent of country's population is living in rural areas and is directly or indirectly linked with agriculture for their livelihood. It also supplies raw materials to industry. The rice-wheat zone of Punjab covers 1.1 million hectare, 72% of wheat is grown in rotation with rice. The main purpose of this paper was to determine the effect of different factors on the productivity and ultimately on income from of major crops (wheat, rice and sugar-cane) in rice-wheat ecological zone. The results show that for wheat crop, land preparation, use of fertilizer and chemicals, for Sugarcane crop, area under cultivation, fertilizer and chemical costs and for rice crop, applications of chemicals, irrigation and land holding were the main determinants of productivity and crop income. (author)

  16. Morphological and molecular variation of five rice varieties to Ultra Violet-B radiation stress

    Directory of Open Access Journals (Sweden)

    A. John De Britto

    2011-09-01

    Full Text Available India is one of the major rice producing countries. Rice cultivation is affected by several factors such as climate, soil pollution, UV radiation etc. The present study is an attempt made to understand the morphological variation and molecular variation through SDS-PAGE in five different rice varieties induced with UV-B stress. Five varieties of rice were irradiated with UV-B for 10, 20 and 30 min and a set was maintained as control for every variety. Morphological variations were estimated using morphometric analysis that showed significant variation in stressed and controlled sets. The leaf protein was separated through SDS-PAGE gel electrophoresis and molecular weight markers were used to calculate the molecular weight of the proteins. UV treated varieties had the lowest record based on the banding pattern than the control. These results show that the UV radiation could induce both phenotypic and genotypic changes in rice.

  17. Agrobiodiversity of Muda Rice Agroecosystem:A case Study in Largest Granary Area of Malaysia

    Institute of Scientific and Technical Information of China (English)

    Amir Shah Ruddin Md Shah; Mashhor Mansor; Shahrul Anuar Mohd Shah; Che Salmah Mohd Rawi; Abu Hassan Ahmad; Ibrahim Jaafar

    2008-01-01

    A survey was carried out at the largest rice cultivation area in Peninsular Malaysia, the Muda rice agroecosystem. The main objective of this study was to document the overall biodiversity associated with this unique agroecosystem by using a combination of sampling techniques in order to record different groups of fauna and flora. The total number of biota recorded and identified from the rice field ecosystem during the study period consisted of 46 species of zooplankton, 81 species of aquatic insects, 5 species of rodents, 7 species of bats, 87 species of birds, 11 species of fishes and 58 species of weeds. A long-term study should be carried out as more species are expected to be recorded when more of the Muda rice agroecosystem area has been sampled to obtain sufficient information on the Muda rice agrobiodiversity.

  18. South Asian Cluster

    Directory of Open Access Journals (Sweden)

    Ionel Sergiu Pirju

    2014-12-01

    Full Text Available This article aims at presenting the South Asian cluster composed of India, Indonesia, Iran and Malaysia, the intercultural values that characterizes it, the supported leadership style and tracing the main macroeconomic considerations which characterizes them. The research is synchronic, analysing the contemporary situation of these countries without reference to their evolution in time, by using the positivist paradigm that explains the reality at one point. It will be analysed the overall cluster with the existing interactions between the countries that composes it, while the article being one of information will avoid building recommendation, or new theories.

  19. Chemical, Sensorial and Rheological Properties of a New Organic Rice Bran Beverage

    Institute of Scientific and Technical Information of China (English)

    Gerson Luis FACCIN; Leila do Nascimento VIEIRA; Letícia Adélia MIOTTo; Pedro Luiz Manique BARRETO; Edna Regina AMANTE

    2009-01-01

    Rice bran is a solid residue from rice polishing that is used in animal nutrition and rice oil production. Cultivation conditions with agro-toxics, lipids instability, and tendency for mycotoxin contamination restrict its application in human nutrition. Therefore, organic agriculture is an alternative to use the properties of rice bran. Rice bran beverage is a new cereal product from organic rice. This work presents the preliminary results of the chemical and rheological studies of a bath pasteurized rice bran beverage. Compared with integral defatted milk, soy extracts, and brown rice low-fat milk, the rice bran beverage studied in this work presents itself as an important source of minerals and unsaturated lipids. All essential amino acids were found in this product. Glutamic and aspartic acids were predominant. Bath pasteurization at boiling water temperature for 15 and 30 min was adequate for microbiological safety. Refrigeration storage for 20 days, evaluated by pH and acidity variations, was ideal for assessment of the beverage conservation time. The beverage viscosity was of the Newtonian standard behavior, and its viscosity during storage was not a good parameter to evaluate shelf life. Sensory preference tests showed positive perspectives for this new beverage.

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

    Science.gov (United States)

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

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

  1. Estrutura fitossociológia de um fragmento natural de floresta inundável em área de orizicultura irrigada, município de Lagoa da Confusão, Tocantins Phytosociologial structure of a natural fragment of floodplain forest in area of irrigated rice cultivation, municipal district of Lagoa da Confusão, Tocantins, Brazil

    Directory of Open Access Journals (Sweden)

    Elizabeth Rodrigues Brito

    2006-10-01

    , inserted in area of irrigated rice cultivation. For the phytosociological survey, all the tree/shrub individuals with perimeter at 1.30m (PBH > 15 cm were sampled. On the whole, 807 individuals, 35 families and 70 species were sampled. The species with higher VC, in descending order, were Hirtella racemosa Lam., Qualea multiflora Mart. and Cecropia pachystachya Trécul. The richest families in species were Fabaceae (9, Vochysiaceae (6, Annonaceae and Malvaceae (4. The Shannon diversity index (H' was 3.44. The distribution of diameter classes showed an inverted "J" curve, with most of the individuals being in the first class.

  2. 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.

  3. A built-in mechanism to mitigate the spread of insect-resistance and herbicide-tolerance transgenes into weedy rice populations.

    Directory of Open Access Journals (Sweden)

    Chengyi Liu

    Full Text Available BACKGROUND: The major challenge of cultivating genetically modified (GM rice (Oryza sativa at the commercial scale is to prevent the spread of transgenes from GM cultivated rice to its coexisting weedy rice (O. sativa f. spontanea. The strategic development of GM rice with a built-in control mechanism can mitigate transgene spread in weedy rice populations. METHODOLOGY/PRINCIPAL FINDINGS: An RNAi cassette suppressing the expression of the bentazon detoxifying enzyme CYP81A6 was constructed into the T-DNA which contained two tightly linked transgenes expressing the Bt insecticidal protein Cry1Ab and the glyphosate tolerant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS, respectively. GM rice plants developed from this T-DNA were resistant to lepidopteran pests and tolerant to glyphosate, but sensitive to bentazon. The application of bentazon of 2000 mg/L at the rate of 40 mL/m(2, which is approximately the recommended dose for the field application to control common rice weeds, killed all F(2 plants containing the transgenes generated from the Crop-weed hybrids between a GM rice line (CGH-13 and two weedy rice strains (PI-63 and PI-1401. CONCLUSIONS/SIGNIFICANCE: Weedy rice plants containing transgenes from GM rice through gene flow can be selectively killed by the spray of bentazon when a non-GM rice variety is cultivated alternately in a few-year interval. The built-in control mechanism in combination of cropping management is likely to mitigate the spread of transgenes into weedy rice populations.

  4. Potassium hydroxide pulping of rice straw in biorefinery initiatives.

    Science.gov (United States)

    Jahan, M Sarwar; Haris, Fahmida; Rahman, M Mostafizur; Samaddar, Purabi Rani; Sutradhar, Shrikanta

    2016-11-01

    Rice straw is supposed to be one of the most important lignocellulosic raw materials for pulp mill in Asian countries. The major problem in rice straw pulping is silica. The present research is focused on the separation of silica from the black liquor of rice straw pulping by potassium hydroxide (KOH) and pulp evaluation. Optimum KOH pulping conditions of rice straw were alkali charge 12% as NaOH, cooking temperature 150°C for 2h and material to liquor ratio, 1:6. At this condition pulp yield was 42.4% with kappa number 10.3. KOH pulp bleached to 85% brightness by D0EpD1 bleaching sequences with ClO2 consumption of 25kg/ton of pulp. Silica and lignin were separated from the black liquor of KOH pulping. The amount of recovered silica, lignin and hemicelluloses were 10.4%, 8.4% and 13.0%. The papermaking properties of KOH pulp from rice straw were slightly better than those of corresponding NaOH pulp. PMID:27518034

  5. Improvement results of rice (Oryza glaberima) by induced mutation

    International Nuclear Information System (INIS)

    In Mali, rice (Orzya glaberima) is still largely cultivated under conditions of natural semi-controlled submersion. To improve productivity the local varieties have been gradually replaced by new varieties, but the yields of these became lower because of the irregularity of the rain and the comparative weakness of the strain. For this reason a programme to improve the local varieties by means of gamma radiation has been undertaken. This document presents the results obtained to date

  6. Modeled concentrations in rice and ingestion doses from chronic atmospheric releases of tritium

    International Nuclear Information System (INIS)

    The expansion of nuclear power programs in Asia has stimulated interest in the improved modeling of concentrations of tritium in rice, a staple crop grown throughout the far east. Normally, the specific activity model is used to calculate concentrations of tritium in the tissue water of edible plants to assess ingestion dose from chronic releases. However, because rice, like other grains, has much lower water content than most crops, the calculation must also account for organically bound tritium. This paper reviews ways to calculate steady-state concentrations of tritium in rice, including the methods of Canadian and US regulatory models, and the assumptions behind them. Concentrations in rice and resulting ingestion doses are compared for the various methods, and equations for calculating concentrations are recommended. The regulatory models underestimate doses received from ingestion of rice contaminated with tritium since they do not account explicitly for organically bound tritium. The importance of including organically bound tritium is illustrated in a comparison of doses from rice, leafy vegetables and milk for an Asian diet. Dose factors from tritium for these foods are estimated to be 135, 47, and 20 nSv y-1/(Bq m-3), respectively. Assuming known air concentrations, tritium concentrations in rice, calculated with the recommended equations, are uncertain by less than a factor 2 when tritium concentrations in the rice paddy water are known, and by less than a factor of 2.3 when concentrations in paddy water are unknown

  7. Fermentation Quality and Additives: A Case of Rice Straw Silage.

    Science.gov (United States)

    Oladosu, Yusuff; Rafii, Mohd Y; Abdullah, Norhani; Magaji, Usman; Hussin, Ghazali; Ramli, Asfaliza; Miah, Gous

    2016-01-01

    Rice cultivation generates large amount of crop residues of which only 20% are utilized for industrial and domestic purposes. In most developing countries especially southeast Asia, rice straw is used as part of feeding ingredients for the ruminants. However, due to its low protein content and high level of lignin and silica, there is limitation to its digestibility and nutritional value. To utilize this crop residue judiciously, there is a need for improvement of its nutritive value to promote its utilization through ensiling. Understanding the fundamental principle of ensiling is a prerequisite for successful silage product. Prominent factors influencing quality of silage product include water soluble carbohydrates, natural microbial population, and harvesting conditions of the forage. Additives are used to control the fermentation processes to enhance nutrient recovery and improve silage stability. This review emphasizes some practical aspects of silage processing and the use of additives for improvement of fermentation quality of rice straw.

  8. Fermentation Quality and Additives: A Case of Rice Straw Silage

    Science.gov (United States)

    Oladosu, Yusuff; Magaji, Usman; Hussin, Ghazali; Ramli, Asfaliza; Miah, Gous

    2016-01-01

    Rice cultivation generates large amount of crop residues of which only 20% are utilized for industrial and domestic purposes. In most developing countries especially southeast Asia, rice straw is used as part of feeding ingredients for the ruminants. However, due to its low protein content and high level of lignin and silica, there is limitation to its digestibility and nutritional value. To utilize this crop residue judiciously, there is a need for improvement of its nutritive value to promote its utilization through ensiling. Understanding the fundamental principle of ensiling is a prerequisite for successful silage product. Prominent factors influencing quality of silage product include water soluble carbohydrates, natural microbial population, and harvesting conditions of the forage. Additives are used to control the fermentation processes to enhance nutrient recovery and improve silage stability. This review emphasizes some practical aspects of silage processing and the use of additives for improvement of fermentation quality of rice straw. PMID:27429981

  9. Dissipation gradients of phenanthrene and pyrene in the Rice rhizosphere

    International Nuclear Information System (INIS)

    An experiment was conducted to reveal the effects of rice cultivation as well as polycyclic aromatic carbohydrates (PAHs) degrading bacterium (Acinetobacter sp.) on the dissipation gradients of two PAHs (PHE and PYR) in the rhizosphere. The results showed that the presence of rice root and bacteria significantly accelerated the dissipation rate of PHE and PYR. The root exudates contributed to the formation of dissipation gradients of PHE and PYR along the vertical direction of roots, with a higher dissipation rate in the rhizosphere and near rhizosphere zone than the soil far away the rhizosphere. - The formation of dissipation gradients of PAHs were attributed to the presence of rice root and the degrading bacteria in paddy soil.

  10. Monitoring and Management of Imidazolinone-Resistant Red Rice (Oryza sativa L., var. sylvatica in Clearfield® Italian Paddy Rice

    Directory of Open Access Journals (Sweden)

    Laura Scarabel

    2012-12-01

    Full Text Available The introduction in Italy of Clearfield® rice cultivars carrying imidazolinone-resistant traits provides an efficient option to control red rice, a conspecific weed of cultivated rice. However, despite the promulgation of specific guidelines for Clearfield® technology management, imazamox red rice survivors have been reported by farmers. Forty-two fields were monitored in 2010 and 2011 throughout the Piedmont and Lombardy regions and field cases were recorded of herbicides use and agronomic practices. Whole-plant sensitivity to imazamox was assessed and the resistance mechanism was determined by molecular analysis. Twenty-six red rice populations out of 42 were imazamox-resistant and plants of all the resistant populations possess a Ser to Asn substitution at locus 653 of the ALS gene determining the target-site resistance. Farmers frequently grow Clearfield® varieties for more than two consecutive years so increasing the selection pressure exerted by imazamox and favoring the evolution of resistant red rice. To maintain the sustainability of this new technology, a proper management based on crop rotation, utilization of certified seeds and strict control of red rice escapes has to be implemented. More generally, all stakeholders must increase their awareness that the selection pressure exerted by ALS inhibitors in rice cropping system should be reduced.

  11. From Early Domesticated Rice of the Middle Yangtze Basin to Millet, Rice and Wheat Agriculture: Archaeobotanical Macro-Remains from Baligang, Nanyang Basin, Central China (6700-500 BC.

    Directory of Open Access Journals (Sweden)

    Zhenhua Deng

    Full Text Available Baligang is a Neolithic site on a northern tributary of the middle Yangtze and provides a long archaeobotanical sequence from the Seventh Millennium BC upto the First Millennium BC. It provides evidence for developments in rice and millet agriculture influenced by shifting cultural affiliation with the north (Yangshao and Longshan and south (Qujialing and Shijiahe between 4300 and 1800 BC. This paper reports on plant macro-remains (seeds, from systematic flotation of 123 samples (1700 litres, producing more than 10,000 identifiable remains. The earliest Pre-Yangshao occupation of the sites provide evidence for cultivation of rice (Oryza sativa between 6300-6700 BC. This rice appears already domesticated in on the basis of a dominance of non-shattering spikelet bases. However, in terms of grain size changes has not yet finished, as grains are still thinner than more recent domesaticated rice and are closer in grain shape to wild rices. This early rice was cultivated alongside collection of wild staple foods, especially acorns (Quercus/Lithicarpus sensu lato. In later periods the sites has evidence for mixed farming of both rice and millets (Setaria italica and Panicum miliaceum. Soybean appears on the site in the Shijiahe period (ca.2500 BC and wheat (Triticum cf. aestivum in the Late Longshan levels (2200-1800 BC. Weed flora suggests an intensification of rice agriculture over time with increasing evidence of wetland weeds. We interpret these data as indicating early opportunistic cultivation of alluvial floodplains and some rainfed rice, developing into more systematic and probably irrigated cultivation starting in the Yangshao period, which intensified in the Qujialing and Shijiahe period, before a shift back to an emphasis on millets with the Late Longshan cultural influence from the north.

  12. South Asian Families in Diaspora

    DEFF Research Database (Denmark)

    Singla, Rashmi

    2008-01-01

      South Asian Family in Diaspora: Retreat from marriage, myth or reality?   This paper proposes to explore the dynamics of close ties in the South Asian families in the Nordic countries, especially Denmark through intimate partnership formation in the context of late modern societal discourse...

  13. PETROCHINA TOPS ASIAN COMPETITIVENESS RANKING

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    PetroChina, the largest oil producer in China, ranks first in a competitiveness report of listed Asian enterprises recently published by the Research Institute of Boao Forum for Asia. The oil giant tops the ranks in the Asian Competitiveness: Annual Repor

  14. Phenotypic Diversity of Farmers’ Traditional Rice Varieties in the Philippines

    Directory of Open Access Journals (Sweden)

    Roel C. Rabara

    2014-05-01

    Full Text Available Traditional rice varieties maintained and cultivated by farmers are likely sources of germplasm for breeding new rice varieties. They possess traits potentially adaptable to a wide range of abiotic and biotic stresses. Characterization of these germplasms is essential in rice breeding and provides valued information on developing new rice cultivars. In this study, 307 traditional rice varieties newly conserved at the PhilRice genebank were characterized to assess their phenotypic diversity using 57 morphological traits. Using the standardized Shannon-Weaver diversity index, phenotypic diversity indices averaged at 0.73 and 0.45 for quantitative and qualitative traits, respectively. Correlation analyses among agro-morphological traits showed a high positive correlation in some traits such as culm number and panicle number, flag leaf width and leaf blade width, grain width and caryopsis width. Cluster analysis separated the different varieties into various groups. Principal component analysis (PCA showed that seven independent principal components accounted for 74.95% of the total variation. Component loadings for each principal component showed morphological characters, such as culm number, panicle number and caryopsis ratio that were among the phenotypic traits contributing positive projections in three principal components that explained 48% of variation. Analyses of results showed high diversity in major traits assessed in farmers’ rice varieties. Based on plant height and maturity, 11 accessions could be potential donor parents in a rice breeding program. Future collection trips and characterization studies would further enrich diversity, in particular traits low in diversity, such as anthocyanin coloration, awn presence, awn color, culm habit, panicle type and panicle branching.

  15. Super Rice Breeding in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@I. Demand for super high yield rice in China   Rice is one of the main staple food in China. The performance of rice sector in production and yield had been very impressive in the last four decades. However, rice production and yield has stagnated since 1990.

  16. Rice Varietal Improvement and International Exchange of Rice Germplasm

    OpenAIRE

    Evenson, Robert E.

    1997-01-01

    Rice is the most important food grain in developing countries. Rapid population growth in developing countries during the 1950s and 1960s presented a massive challenge to rice producers. Rice production would have to be expanded at historically unprecedented rates to maintain per capita rice consumption levels. That challenge was met. Rice production expanded more rapidly than population. The challenge was met primarily by increased yields per hectare of land. This paper documents the role of...

  17. The oryza map alignment project: the golden path to unlocking the genetic potential of wild rice species.

    Science.gov (United States)

    Wing, Rod A; Ammiraju, Jetty S S; Luo, Meizhong; Kim, Hyeran; Yu, Yeisoo; Kudrna, Dave; Goicoechea, Jose L; Wang, Wenming; Nelson, Will; Rao, Kiran; Brar, Darshan; Mackill, Dave J; Han, Bin; Soderlund, Cari; Stein, Lincoln; SanMiguel, Phillip; Jackson, Scott

    2005-09-01

    The wild species of the genus Oryza offer enormous potential to make a significant impact on agricultural productivity of the cultivated rice species Oryza sativa and Oryza glaberrima. To unlock the genetic potential of wild rice we have initiated a project entitled the 'Oryza Map Alignment Project' (OMAP) with the ultimate goal of constructing and aligning BAC/STC based physical maps of 11 wild and one cultivated rice species to the International Rice Genome Sequencing Project's finished reference genome--O. sativa ssp. japonica c. v. Nipponbare. The 11 wild rice species comprise nine different genome types and include six diploid genomes (AA, BB, CC, EE, FF and GG) and four tetrapliod genomes (BBCC, CCDD, HHKK and HHJJ) with broad geographical distribution and ecological adaptation. In this paper we describe our strategy to construct robust physical maps of all 12 rice species with an emphasis on the AA diploid O. nivara--thought to be the progenitor of modern cultivated rice. PMID:16217601

  18. Induction of drought tolerant mutants of rice

    International Nuclear Information System (INIS)

    The ultimate goal of crop breeding is to develop varieties with a high yield potential and desirable agronomic characteristics. In Egypt, the most important qualities sought by breeders have been high yield potential, resistance to major diseases and insects, and improved grain and eating quality. However, breeding efforts should concentrate on varieties with the potential to minimize yield losses under unfavorable conditions such as drought, and to maximize yields when conditions are favorable. Rice (Oryza sativa L.) in Egypt is completely irrigated and a significant portion of the rice cultivated area is subject to water deficit resulting from an inadequate or insufficient irrigation supply. Drought tolerance is a complex trait in that it results from the interaction of histological and physiological characters of plant with environmental factors, both above-ground and under-ground. Accordingly, root characters are closely related to drought tolerance. Little attention has been paid in Egyptian breeding programs to root characters and their relation to shoot characters. Furthermore, induced mutations are considered as one of the most important methods to induce useful mutants, especially with improved root characters, to overcome the drought problem. The present investigation aimed to study the effect of different doses of gamma rays on several characters of three Egyptian rice varieties, i.e. 'Giza 171', 'Giza 175' and 'Giza 176' and to induce one or more mutants possessing drought tolerance

  19. A Century of Rice Innovations

    OpenAIRE

    Halos, Saturnina C.

    2005-01-01

    Rice innovations are technologies and practices extensively adopted so as to change production practices and productivity. This paper documents the changes in rice productivity, policy and institutions in the last 100 years and identifies the technological change that may have affected rice productivity. One hundred years has totally changed rice production practices and improved productivity. Technical innovations that helped improved rice productivity include irrigation, pest management not...

  20. Screening of Exist Genetically Modified Elements in Local and Commercial Rice Available in Baghdad Markets Using PCR and Real-time PCR

    Directory of Open Access Journals (Sweden)

    Hayba Q. Younan

    2013-11-01

    Full Text Available Rice is one of the staple foods of the Iraqi population; therefore large amounts of rice cultivated and imported in Iraq. Because of increasing the production of GM crops especially rice crop, it was necessary to investigate if there is any genetically modified rice (GM rice in Baghdad markets. Conventional PCR and Real-Time PCR used to create this investigation. Genomic DNA extracted from 7 samples of rice seeds that cultivated in Iraq; 31 samples of commercial rice seeds and 4 samples of kids' food, where rice is one of their ingredients. The primers RM 171 selected to amplify the Rice Microsatellite Region (RM for the DNA integrity inspection and rice species detection especially samples of kids' food, as well as, the primers P35S selected to amplify the CaMV35S promoter region (P35S for Genetically Modified elements (GM elements detection. There was no existence of GM elements in all samples except one, which was one of kids' food samples. These results indicate that the ability to produce GM crops and monitoring of the GM food entry are limitable in Iraq. Moreover, no commitment in the labeling regulations of genetically modified food.

  1. Changes in Soil Properties of Paddy Fields Across A Cultivation Chronosequence in Subtropical China

    Institute of Scientific and Technical Information of China (English)

    LI Zhong-Pei; ZHANG Tao-Lin; LI De-Cheng; B.VELDE; HAN Feng-Xiang

    2005-01-01

    Rice production plays a crucial role ia the food supply of China and a better understanding of the changes in paddy soil fertility and the management effects is of practical importance for increasing rice productivity. In this study, field sampling in a typical red soil region of subtropical China, Jiangxi Province, was used to observe changes in the soil physical, chemical,and biological properties in a cultivation chronosequence of paddy fields. After cultivation, clay (< 0.002 mm) content in the soil, which was 39% in the original uncultivated wasteland, decreased to 17% in the 80-year paddy field, while silt(0.02-0.002 mm) content increased. Additionally, macroporosity increased and pore shapes became more homogeneous.Soil pH generally increased. Soil organic C and total N contents of the 0-10 cm layer increased from 4.58 and 0.39 g kg-1to 19.6 and 1.62 g kg-1, respectively, in the paddy fields after 30-year cultivation and then remained stable. Soil total P content increased from 0.5 to 1.3 g kg-1 after 3 years of rice cultivation, indicating that application of phosphate fertilizer could accelerate phosphorous accumulation in the soil. Total K content in the 0-10 cm soil layer for the 80-year paddy field decreased by 28% compared to that of the uncultivated wasteland land. Total Fe and free Fe contents declined with years of cultivation. The bacterial population increased and urease activity noticeably intensified after years of cultivation.In this chronosequence it appeared that it took 30 years to increase soil fertility to a relatively constant value that was seen after 80 years of cultivation.

  2. Searching for South Asian intelligence: psychometry in British India, 1919-1940.

    Science.gov (United States)

    Setlur, Shivrang

    2014-01-01

    This paper describes the introduction and development of intelligence testing in British India. Between 1919 and 1940 experimenters such as C. Herbert Rice, Prasanta Chandra Mahalanobis, and Venkatrao Vithal Kamat imported a number of intelligence tests, adapting them to suit a variety of South Asian languages and contexts. Charting South Asian psychometry's gradual move from American missionary efforts toward the state, this paper argues that political reforms in the 1920s and 1930s affected how psychometry was "indigenized" in South Asia. Describing how approaches to race and caste shifted across instruments and over time, this paper charts the gradual recession, within South Asian psychometry, of a "race" theory of caste. Describing some of the ways in which this "late colonial" period affected the postcolonial landscape, the paper concludes by suggesting potential lines for further inquiry into the later career of intelligence testing in India and Pakistan. PMID:25183435

  3. The Confucian Asian cluster

    Directory of Open Access Journals (Sweden)

    Ionel Sergiu Pirju

    2013-11-01

    Full Text Available The Confucian Asian cluster consists of China, Hong Kong, Japan, Singapore, South Korea, and Taiwan. Confucian tradition countries were defined by achieving a consistent performance in the global economy, they still representing the major competitors in the EU and North American countries. Their progress is defined by a great national management that was able to influence beneficial management systems applied in organizations, these rules characterized by authority; aims to ensure the confidence in business. This article will present the intercultural values characterizing it, the leadership style and also tracing major macroeconomic considerations. The research is synchronic, analysing the contemporary situation of these countries, and the analysis will be interdisciplinary exploratory, identifying specific regional cultural elements.

  4. Changes in the concentration of fumonisins in forage rice during the growing period, differences among cultivars and sites, and identification of the causal fungus.

    Science.gov (United States)

    Uegaki, Ryuichi; Tohno, Masanori; Yamamura, Kohji; Tsukiboshi, Takao

    2014-04-16

    To clarify the changes in rice fumonisin (FUM) concentrations, we conducted field cultivation of 10 forage rice cultivars and inoculation with fumonisin-producing fungal isolates. We cultivated 10 forage rice cultivars at the NARO Institute of Livestock and Grassland Science and one cultivar at two additional farmland sites in Japan in 2011 and 2012. Fusarium fujikuroi, which primarily infects plants shortly after heading, was inoculated on rice just after heading, and we sampled heads at the yellow-ripe and full-ripe stages to assess FUM concentrations. We found differences among cultivars in the FUM concentration and differences among the sites for the same cultivar, but no cultivar had high levels in leaves and stems. Fusarium fujikuroi was the main fumonisin producer. The FUM concentration in heads increases from stage. To control FUM levels, it is necessary to select low-FUM cultivars and manage the cultivation environment. PMID:24628734

  5. Some results of NAA collaborative study in white rice performed at Dalat Nuclear Research Institute

    International Nuclear Information System (INIS)

    White rice is a main food for Asian people. In the framework of Forum for Nuclear Cooperation in Asia (FNCA), therefore, the eight Asian countries: China, Indonesia, Japan, Korea, Malaysia, the Philippines, Thailand and Vietnam selected white rice as a common target sample for a collaboration study since 2008. Accordingly, rice samples were purchased and prepared by following a protocol that had been proposed for this study. The groups of elements that were analyzed by using neutron activation analysis in the white rice samples were toxic elements and nutrient elements, including: Al, As, Br, Ca, Cl, Co, Cr, Cs, Fe, K, Mg, Mn, Na, Rb and Zn. The analytical results were compared between the different countries and evaluated by using the Tolerable Intake Level of World Health Organization (WHO) and Recommended Dietary Allowance or Adequate Intake (AI) of the U.S. Institute of Medicine (IOM) guideline values. These data will be very useful in the monitoring of the levels of food contamination and in the evaluation of the nutritional status for people living in Vietnam and other Asian countries. (author)

  6. High-yielding Cultivation and Fertilization Technology of Lvhan No.1 in Angola

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] The aim was to research high-yielding cultivation and fertilization technology for Lvhan No.l, a new Chinese rice cultivar, in Angola. [Method] In rainy season of 2012, high-yielding cultivation and fertilization technology of Lvhan No.l, a new cultivar of earlier ripe and drought resistant rice, was researched in CATETE farm of Luanda suburb with pot experiment method. [Result] In CATETE farm, Lvhan No.1 rice were directly sown in black clay and the rice can be significantly improved in plant height, grain weight of single plant, biological yield of single plant, ear length, total grain number per ear, number of filled grain per ear and thousand seed weight, as well as economic coefficient and ratio of grain to straw, if applied with base fertilizer made up of DAP (N:P2Os=14:43), or compound fertilizer of N, P and K (N:P2Os:K~O=15:15:15) and with Duannai fertilizer and ear-grain fertilizer made up of urea. If DAP is taken as base fertilizer, the optimal quantity is 300 kg/hm2. If compound fertilizer of N, P and K is taken as base fertilizer, the optimal quantity is 450 kg/hm2, but urea at 75 kg/hm2 should be applied as Duannai fertilizer and ear- grain fertilizer, respectively, on time. [Conclusion] The research provides technical ref- erences for planting of Chinese rice cultivars in Angola.

  7. Cultivating strategic thinking skills.

    Science.gov (United States)

    Shirey, Maria R

    2012-06-01

    This department highlights change management strategies that may be successful in strategically planning and executing organizational change initiatives. With the goal of presenting practical approaches helpful to nurse leaders advancing organizational change, content includes evidence-based projects, tools, and resources that mobilize and sustain organizational change initiatives. In this article, the author presents an overview of strategic leadership and offers approaches for cultivating strategic thinking skills.

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

    Energy Technology Data Exchange (ETDEWEB)

    Arao, Tomohito, E-mail: arao@affrc.go.jp [National Institute for Agro-Environmental Sciences, Soil Environmental Division, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-8604 (Japan); Maejima, Yuji; Baba, Koji [National Institute for Agro-Environmental Sciences, Soil Environmental Division, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-8604 (Japan)

    2011-10-15

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

  9. Racism and Asian American Student Leadership

    Science.gov (United States)

    Chung, Jennifer Y.

    2014-01-01

    This article provides a theoretical analysis and ethnographic account of Asian American student leadership in higher education. Existing literature highlights Asian and Asian American leadership styles as cultural differences. I shift the analysis from culture to racism in order to work toward a more socially just conception of Asian American…

  10. Diabetes and Asians and Pacific Islanders

    Science.gov (United States)

    ... diabetes per 100 population (2014) Asian American White Asian American/White Ratio Men 5.8 6.3 0.9 Women 5.7 5.3 1.1 Total 5.8 5.7 1.0 Source: CDC 2016. National Diabetes Surveillance ... Asian American/Pacific Islanders Non-Hispanic White Asian American/Pacific ...

  11. Concentration of radiocaesium in rice and irrigation water, and soil management practices in Oguni, Date, Fukushima.

    Science.gov (United States)

    Tsukada, Hirofumi; Ohse, Kenji

    2016-10-01

    The concentration of radiocaesium ((134) Cs and (137) Cs) in brown rice collected from Oguni, Date, Fukushima in 2011 was over 500 Bq kg(-1) , which was the provisional regulation value in 2011, and rice cultivation was prohibited in 2012. Rice culture was resumed following the application of K fertilizer as a countermeasure in 2013. The concentration of (137) Cs in soils and irrigation water in 2013 was in the range of 1200 to 4000 Bq kg(-1) (n = 31) and 0.078 to 1.1 Bq L(-1) (n = 7), respectively. The concentration of (137) Cs in the dissolved fraction in irrigation water filtered with 0.45 µm pore-size membrane filter was a relatively constant at 0.019 to 0.038 Bq L(-1) (n = 7). The concentration of (137) Cs in brown rice cultivated in the paddy fields after implementing the countermeasure was 1.1 to 24 Bq kg(-1) dry weight (n = 29), which was lower than the Standard Limits (100 Bq kg(-1) ). However, the concentration of Cs in rice cultivated under a similar agricultural management as in 2011 and prior to the Tokyo Electric Power Company Holdings' (TEPCO) Fukushima accident was over the Standard Limits. Integr Environ Assess Manag 2016;12:659-661. © 2016 SETAC. PMID:27640411

  12. Escape to Ferality: The Endoferal Origin of Weedy Rice from Crop Rice through De-Domestication

    Science.gov (United States)

    Gettler, Kyle A.; Burgos, Nilda R.; Fischer, Albert J.

    2016-01-01

    Domestication is the hallmark of evolution and civilization and harnesses biodiversity through selection for specific traits. In regions where domesticated lines are grown near wild relatives, congeneric sources of aggressive weedy genotypes cause major economic losses. Thus, the origins of weedy genotypes where no congeneric species occur raise questions regarding management effectiveness and evolutionary mechanisms responsible for weedy population success. Since eradication in the 1970s, California growers avoided weedy rice through continuous flood culture and zero-tolerance guidelines, preventing the import, presence, and movement of weedy seeds. In 2003, after decades of no reported presence in California, a weedy rice population was confirmed in dry-seeded fields. Our objectives were to identify the origins and establishment of this population and pinpoint possible phenotypes involved. We show that California weedy rice is derived from a different genetic source among a broad range of AA genome Oryzas and is most recently diverged from O. sativa temperate japonica cultivated in California. In contrast, other weedy rice ecotypes in North America (Southern US) originate from weedy genotypes from China near wild Oryza, and are derived through existing crop-wild relative crosses. Analyses of morphological data show that California weedy rice subgroups have phenotypes like medium-grain or gourmet cultivars, but have colored pericarp, seed shattering, and awns like wild relatives, suggesting that reversion to non-domestic or wild-like traits can occur following domestication, despite apparent fixation of domestication alleles. Additionally, these results indicate that preventive methods focused on incoming weed sources through contamination may miss burgeoning weedy genotypes that rapidly adapt, establish, and proliferate. Investigating the common and unique evolutionary mechanisms underlying global weed origins and subsequent interactions with crop relatives sheds

  13. Assessing energy efficiencies and greenhouse gas emissions under bioethanol-oriented paddy rice production in northern Japan.

    Science.gov (United States)

    Koga, Nobuhisa; Tajima, Ryosuke

    2011-03-01

    To establish energetically and environmentally viable paddy rice-based bioethanol production systems in northern Japan, it is important to implement appropriately selected agronomic practice options during the rice cultivation step. In this context, effects of rice variety (conventional vs. high-yielding) and rice straw management (return to vs. removal from the paddy field) on energy inputs from fuels and consumption of materials, greenhouse gas emissions (fuel and material consumption-derived CO(2) emissions as well as paddy soil CH(4) and N(2)O emissions) and ethanol yields were assessed. The estimated ethanol yield from the high-yielding rice variety, "Kita-aoba" was 2.94 kL ha(-1), a 32% increase from the conventional rice variety, "Kirara 397". Under conventional rice production in northern Japan (conventional rice variety and straw returned to the paddy), raising seedlings, mechanical field operations, transportation of harvested unhulled brown rice and consumption of materials (seeds, fertilizers, biocides and agricultural machinery) amounted to 28.5 GJ ha(-1) in energy inputs. The total energy input was increased by 14% by using the high-yielding variety and straw removal, owing to increased requirements for fuels in harvesting and transporting harvested rice as well as in collecting, loading and transporting rice straw. In terms of energy efficiency, the variation among rice variety and straw management scenarios regarding rice varieties and rice straw management was small (28.5-32.6 GJ ha(-1) or 10.1-14.0 MJ L(-1)). Meanwhile, CO(2)-equivalent greenhouse gas emissions varied considerably from scenario to scenario, as straw management had significant impacts on CH(4) emissions from paddy soils. When rice straw was incorporated into the soil, total CO(2)-equivalent greenhouse gas emissions for "Kirara 397" and "Kita-aoba" were 25.5 and 28.2 Mg CO(2) ha(-1), respectively; however, these emissions were reduced notably for the two varieties when rice straw

  14. Gas transport through the root-shoot transition zone of rice tillers

    NARCIS (Netherlands)

    Groot, TT; van Bodegom, PM; Meijer, HAJ; Harren, FJM

    2005-01-01

    Rice plants (Oryza sativa L.) are mainly cultivated in flooded paddy fields and are thus dependent on oxygen transport through the plant to maintain aerobic root metabolism. This gas transport is effectuated through the aerenchyma of roots and shoots. However, the efficiency of gas transport through

  15. Selection of tolerant rice germplasm through phenotypic and genotypic evaluation for germination under low temperatures

    Science.gov (United States)

    Low temperature germinability (LTG) is an important trait for stand establishment in the direct-seeding method of rice cultivation. In temperate growing regions, water temperature during sowing season is frequently below 15°C resulting in poor crop establishment. The objective of this study was to s...

  16. Isolation and Characterisation of Diazotrophic Bacteria from Rhizosphere of Different Rice Cultivars of South Assam, India

    OpenAIRE

    FOLGUNI LASKAR; Sharma, G. D.

    2013-01-01

    Free living heterotrophic bacteria were isolated from the rhizosphere of 10 local and cultivated varieties of rice grown in Karimganj district of South Assam. Among the 25 isolates, 11 isolates withplant growth promoting activity were identified based on phenotypic and 16S rDNA sequence analysis. The strains were identified as Shingomonasazotifigens, Pseudomonas putida, Stenotrophomonasmaltophila,Acinetobacterradioresistance, Alkaligenesfaecalis, Enterobactercloaceae subsp. dissolvens, Pant...

  17. Cutaneous Mycoses among Rice Farmers in Anambra State, Nigeria

    Directory of Open Access Journals (Sweden)

    Chito Clare Ekwealor

    2013-01-01

    Full Text Available Rice grain is one of the world's most important food crops, and its cultivation is a major occupation in Anambra State, Nigeria. These rice farmers are exposed to various agents that predispose them to cutaneous mycoses. The aim of this work was to screen rice farmers for lesions suggestive of cutaneous mycoses and to isolate and identify fungal agents associated with the infection. This survey was carried out between November 2009 and June 2011 in Anambra State, Nigeria. Clinical samples collected from 201 farmers with lesions suggestive of cutaneous mycoses were processed and the organisms identified. Questionnaires were used to obtain other necessary data and were statistically analyzed. Of the 2,580 rice farmers screened, 201 (7.79% showed positive lesions. Organisms recovered included Microsporum audouinii, Microsporum ferrugineum, Trichophyton megnini, Trichophyton tonsurans, Trichophyton rubrum, Aspergillus terrus, Aspergillus candidus, Aspergillus scleriotorum, Aspergillus niger, Aspergillus flavus, Scopulariopsis sp., Chrysosporium sp., Eupenicillium javanicum, Fusarium sp., Penicillium aculeatum, and Penicillium pinophilum. At the end of this work, onychomycosis was observed to be the most prevalent with nondermatophyte molds now becoming very important agents of cutaneous mycoses among rice farmer.

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

    Science.gov (United States)

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

    2013-01-01

    Rice is one of the most important model crop plants whose heterosis has been well-exploited in commercial hybrid seed production via a variety of types of male-sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility (CMS), photoperiod-sensitive male sterility, self-incompatibility, and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein, and integrated network levels, and also, present a perspective on the engineering of male-sterile lines for hybrid rice production.

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

    Directory of Open Access Journals (Sweden)

    Wang eKun

    2013-04-01

    Full Text Available Rice is one of the most important model crop plants whose heterosis has been well exploited in commercial hybrid seed production via a variety of types of male sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility, photoperiod sensitive male sterility, self-incompatibility and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein and integrated network levels, and also, present a perspective on the engineering of male sterile lines for hybrid rice production.

  20. Promising mutant variety of rice evolved through gamma irradiation

    International Nuclear Information System (INIS)

    Rice occupies a major share in crop production in the Chotanagpur plateau of Bihar State. Uplands are roughly 40% in area where traditional low yielding rice, known as ''gora'' is cultivated as directly sown crop. Despite introduction of high yielding rice varieties, gora group of rices continue to prevail. It is therefore desired to increase the productivity level of the gora rice by mutation breeding. One such mutant known as ''gora mutant'' was obtained through gamma irradiation (10 kR) of variety Brown gora. The maturity of both parent and mutant remaining constant (ie. 100 days), there is some improvement in other characteristics like plant height, tillering capacity and kernel character. The parent being tall, shy in tillering and red bold kernel, the mutant has dwarfish characteristics, profuse tillering habit and white kernel with fine grains. The yielding capacity of mutant derivative is 30-40% higher than the parent Brown gora. This variety is in pre-release stage, and the farmers have taken great liking for it. (author)

  1. Nitrous Oxide Emissions from Upland Farmland as Affected by Summer Legume Crop Cultivation

    Institute of Scientific and Technical Information of China (English)

    XIONG Zheng-qin; XING Guang-xi; H Tsuruta; SHI Shu-lian; SHEN Guang-yu; DU Li-juan; QIAN Wei

    2002-01-01

    A field study was conducted to investigate the effects of leguminous crop cultivation on nitrousoxide (N2O) emissions from upland agricultural soils. Results demonstrated that N2O emission sequences were tively. While in terms of seasonal emission, the sequence was that soybean > peanut crop > upland rice, being 0.77, 0.70 and 0.55 kg/ha respectively. Results also demonstrated that legume crop treatment emitted much more N2O than non-legume upland rice treatment and that N fertilized treatments emitted more than unand N fertilizer, therefore, were one of the important sources of N2O emissions from agricultural fields.

  2. Glutinous Rice in Pineapple

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Ingredients: 50 grams glutinous rice, one pineapple, 20 grams dried fruits (raisins, walnuts. Chinese wolfberry, Chinese dates, lotus seeds, lily petals, kidney beans and peanuts) Seasonings: 5 grams rock sugar, 5 grams salad oil. Method:

  3. What We Have Learnt in Ten Years′Study of Rice Transgene Flow%转基因水稻基因飘流研究十年回顾

    Institute of Scientific and Technical Information of China (English)

    贾士荣; 钱前; 袁潜华; 王丰; 姚克敏; 裴新梧; 胡凝; 王志兴; 王旭静; 柳武革

    2014-01-01

    China is the largest rice producer worldwide and is one of the origins of Asian cultivated rice as well. Along with the rapid development of transgenic rice in China, the potential impact of rice transgene flow on the environment and food safety has become one of the major concerns. Gene flow is an important parameter in the risk assessment and regulation of transgenic rice on the scientific basis. In accordance with this situation, we have formed a team and systematically studied the rice transgene flow since 2002. The results obtained in recent ten years are as following: (1) the patterns of transgene flow and the major biological and meteorological factors controlling rice gene flow have been elucidated. Following the prevailing wind direction in rice flowering period, a rectangular design of field experiments were conducted at 3 locations(Sanya, Hainan Island;Guangzhou, Guangdong;and Hangzhou, Zhejiang)in 2-3 years by using a homozygous transgenic line L201 or B2 (sister lines) with bar gene inserted, resistant to herbicide Basta, as a pollen donor, and totally 19 non-transgenic rice as recipients, including male sterile (ms) lines, common rice cultivars (CRC), F1 hybrid rice, and common wild rice (Oryza rufipogon). Results indicated that the frequency of transgene flow to ms lines was the highest, while gene flow to CRC and F1 hybrids was the lowest (less than 1%or 0.1%at parallel plantation). The frequency of transgene flow to O. rufipogon was in between. By comparison, the maximum frequency of gene flow to ms lines is one to three orders of magnitude higher than that to O. rufipogon and CRC. Gene flow frequency decreased exponentially as the distance increase, with a sharp cut-off point at about 1-2 m in Guangzhou and Hangzhou, while it was approximately 5m in Sanya. It indicates that the sharp cut-off point is closely related to the wind speed during rice flowering period at a given location. By using a concentric circle design of field experiment and an ms

  4. Pricing American and Asian Options

    OpenAIRE

    Pat Muldowney

    2015-01-01

    An analytic method for pricing American call options is provided; followed by an empirical method for pricing Asian call options. The methodology is the pricing theory presented in "A Modern Theory of Random Variation", by Patrick Muldowney, 2012.

  5. Job satisfaction of Asian Americans.

    Science.gov (United States)

    Weaver, C N; Hinson, S

    2000-04-01

    Since Asian Americans have demographic and labor force characteristics more similar to Euro-Americans than African Americans, one might predict that their job satisfaction would be more like the former than the latter. And, because Asian Americans originating from different countries are heterogeneous in language, culture, and recency of immigration, one might predict that they may report obtaining different amounts of satisfaction from their jobs. However, data from 21 nationally representative opinion surveys from 1972 through 1996 suggest the opposite. Asian Americans (n = 199) reported job satisfaction more like African Americans (n = 1,231) than Euro-Americans (n = 10,709), and Asian Americans from China (n = 53), Japan (n = 44), India (n = 55), and the Philippines (n = 47) reported similar job satisfaction. These differences persisted when age, education, occupation, and personal income were held constant.

  6. Analysis of Active Components and Proteomics of Chinese Wild Rice (Zizania latifolia (Griseb) Turcz) and Indica Rice (Nagina22).

    Science.gov (United States)

    Jiang, Ming-Xia; Zhai, Li-Jie; Yang, Hua; Zhai, Shu-Menghui; Zhai, Cheng-Kai

    2016-08-01

    The ancient Chinese wild rice (Zizania latifolia (Griseb) Turcz) (CWR) has valuable biological and medicinal functions. To assess the advantages lost in modern cultivated rice after domestication, we compared the composition of bioactive compounds and the results of proteomic analysis with those of Indica rice (N22). We used routine methods to determine the protein, total dietary fiber, amino acid, mineral substance, plant secondary metabolites, and amino acid composition of CWR and N22. The protein and mineral contents of CWR were two times that of N22, and the levels of calcium, potassium, magnesium, chromium, iron, and zinc were significantly higher than those of N22 (P sterols, respectively. The amino acid score of CWR was 66.6, which was significantly higher than N22. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) indicated that the main seed proteins of CWR were glutelins, including both acid and alkaline subunits, which were approximately twice those of N22. To investigate the differences in protein profiles between CWR and N22, we conducted two-dimensional electrophoresis (2-DE) analysis of the total proteins in the seeds of the two rice species. 2-DE gels revealed 19 differentially expressed proteins. Information obtained from peptide mass fingerprinting indicates that glutelin precursor caffeoyl coenzyme A (CoA) O-methyltransferase and putative bithoraxoid-like protein can provide good gene sources for improving rice quality. PMID:27533651

  7. Germination Response of MR 219 Rice Variety to Different Exposure Times and Periods of 2450 MHz Microwave Frequency

    OpenAIRE

    Daryush Talei; Alireza Valdiani; Mahmood Maziah; Mohammad Mohsenkhah

    2013-01-01

    Germination is a key process in plants' phenological cycles. Accelerating this process could lead to improvment of the seedling growth as well as the cultivation efficiency. To achieve this, the effect of microwave frequency on the germination of rice seeds was examined. The physiological feedbacks of the MR 219 rice variety in terms of seed germination rate (GR), germination percentage (GP), and mean germination time (MGT) were analyzed by exposing its seeds to 2450 MHz of microwave frequenc...

  8. Weed management through herbicide application in direct-seeded rice and yield modeling by artificial neural network

    OpenAIRE

    Dibakar Ghosh; Singh, Udai P; Krishnendu Ray; Anupam Das

    2016-01-01

    In direct seeded rice (DSR) cultivation, weed is the major constraint mainly due to absence of puddling in field. The yield loss due to weed interference is huge, may be up to 100%. In this perspective, the present experiment was conducted to study the efficacy of selected herbicides, and to predict the rice yield using artificial neural network (ANN) models. The dry weight and density of weeds were recorded at different growth stages and consequently herbicidal efficacy was evaluated. Experi...

  9. Effect of potassium application on root uptake of radiocesium in rice

    International Nuclear Information System (INIS)

    After the Fukushima Daiichi Nuclear Power Plant accident that occurred in March 2011, the concentration of radiocesium in brown rice that has been produced in some area has exceeded the provisional regulation value. In order to decrease the concentration of radiocesium in brown rice, we investigated the effect of the application of potassium fertilizer in rice paddy fields on the root uptake of radiocesium. The observed concentration ratio of 134Cs to 137Cs was 0.81 at the time of sample collection, and the mean concentrations of radiocesium in the soils at depths of 0-5, 5-10, and 10-15 cm were 5879 Bq kg-1 DW, 3223 Bq kg-1 DW and 1835 Bq kg-1 DW, respectively. The results showed that the vertical distribution of radiocesium was not uniform, although the rice paddy fields had been plowed. The concentration of radiocesium at a depth of 0-5 cm in soil collected from the 5 different rice paddy fields was in the range of 2465-7823Bq kg-1 DW, showing an approximately 3-fold variation between the upper and lower limits of the range. The concentration of radiocesium in brown rice cultivated in 5 different fields, was in the range of 52-485 Bq kg-1. The concentration of radiocesium in brown rice was found to be not correlated with that in the soil, and the soil-to-brown rice transfer factor was found to lie in the range of 0.0075-0.11. However, the radiocesium in brown rice decreased with an increase in exchangeable potassium in the soil. The concentration of radiocesium in brown rice also decreased from 370 to 138 Bq kg-1 upon the application of a top dressing of potassium fertilizer. Thus, the application of potassium fertilizer is shown to reduce the concentration of radiocesium in brown rice. (author)

  10. BUSINESS PLAN: SOUTH ASIAN ARTS

    OpenAIRE

    Saran, Sabrina

    2009-01-01

    The intention of this paper is to provide an understanding of South Asian Arts as an organization in the Arts industry in Vancouver. Elements of the company and the industry are explored in order to further comprehend the potential target markets and why they are as such. Due to the current surge in popularity of South Asian arts within mainstream culture, there is great potential in this company. Discussion segues into marketing initiatives that are necessary to compete with key players that...

  11. Alcohol and the Asian Glow

    OpenAIRE

    Young, Brian

    1999-01-01

    Facial flushing is a common hypersensitivity reaction that may be observed in many Asians following low to moderate alcohol consumption. Flushing can be accompanied by other symptoms such as tachycardia, nausea, and dizziness. Recent studies have shown that this flushing reaction is due to the presence of ALDH2*2, an inactive allele for the alcohol dehydrogenase gene found in approximately 50% of Asians. Aldehyde dehydrogenase (ALDH) is an important enzyme in alcohol metabolism, and deficienc...

  12. Lessons from the "Asian Flu"

    OpenAIRE

    Bekić, Darko

    1998-01-01

    What has been underlying the syntagms "Japanese challenge ", " Asian miracle " or " Seven Asian tigers " in the past thirty years or so ? There are a number of economic, sociological and political explanations of the phenomenon. In Asia, the systems of traditional values, modern market economy and state are successfully combined. Some forecasters predicted last year that the future growth of the Chinese economy at a constant rate of between 8 and 12 per cent a year, combined with the Japanese...

  13. Bounds for Asian basket options

    Science.gov (United States)

    Deelstra, Griselda; Diallo, Ibrahima; Vanmaele, Michèle

    2008-09-01

    In this paper we propose pricing bounds for European-style discrete arithmetic Asian basket options in a Black and Scholes framework. We start from methods used for basket options and Asian options. First, we use the general approach for deriving upper and lower bounds for stop-loss premia of sums of non-independent random variables as in Kaas et al. [Upper and lower bounds for sums of random variables, Insurance Math. Econom. 27 (2000) 151-168] or Dhaene et al. [The concept of comonotonicity in actuarial science and finance: theory, Insurance Math. Econom. 31(1) (2002) 3-33]. We generalize the methods in Deelstra et al. [Pricing of arithmetic basket options by conditioning, Insurance Math. Econom. 34 (2004) 55-57] and Vanmaele et al. [Bounds for the price of discrete sampled arithmetic Asian options, J. Comput. Appl. Math. 185(1) (2006) 51-90]. Afterwards we show how to derive an analytical closed-form expression for a lower bound in the non-comonotonic case. Finally, we derive upper bounds for Asian basket options by applying techniques as in Thompson [Fast narrow bounds on the value of Asian options, Working Paper, University of Cambridge, 1999] and Lord [Partially exact and bounded approximations for arithmetic Asian options, J. Comput. Finance 10 (2) (2006) 1-52]. Numerical results are included and on the basis of our numerical tests, we explain which method we recommend depending on moneyness and time-to-maturity.

  14. Soil potassium dynamics under intensive rice cropping. A case study in the Mekong Delta, Vietnam

    OpenAIRE

    Nguyen, M.H.

    2003-01-01

    Keywords:potassium, nutrient budgets, nutrient depletion, fertilizer, kinetics, adsorption,desorption, fixation, release, modeling, rice cropping system,NaTPB-extractable K, NH 4 OAc-extractable K, sedimentation.           Rice cropping has been greatly intensified in many Asian countries during the last decades to meet the increasing demand for food by the increasing population. There is some concern now that the increased crop yields and nutrient withdrawal, in combination with unbalanced f...

  15. Asian migration to Australia: food and health consequences.

    Science.gov (United States)

    Wahlqvist, Mark L

    2002-01-01

    Australia's food and health patterns are inextricably and increasingly linked with Asia. Indigenous Australians arrived in the continent via Asia and have linguistic connections with people who settled in south India; there was interaction and food trade between both South-East Asia and China and northern indigenous Australians over thousands of years. After European settlement in 1788, there have been several and increasing (apart from the period of the infamous White Australian Policy following the Colonial period and Independence, with Federation, in 1901) waves of Asian migration, notably during the gold rush (Chinese), the building of the overland Telegraph (Afghans), the Colombo Plan and Asian student education in Australia from the 1950s onwards (South-Eeast Asians), and with refugees (Vietnamese and mainland Chinese), and business (late twentieth century) and progressive family reunion. Each wave has injected additional food cultural elements and caused a measure of health change for migrants and host citizens. Of principal advantage to Australia has been the progressive diversification of the food supply and associated health protection. This has increased food security and sustainability. The process of Australian eating patterns becoming Asianized is evident through market garden development (and the introduction of new foods), fresh food markets and groceries, restaurants and the development of household cooking skills (often taught by student boarders). Most of the diversification has been with grain (rice), legumes (soy), greens, root vegetables, and various 'exotic fruits'. Food acculturation with migration is generally bi-directional. Thus, for Asians in Australia, there has been a decrease in energy expenditure (and a lower plane of energy throughput), an increase in food energy density (through increased fat and sugary drink intakes), and a decrease in certain health protective foods (lentils, soy, greens) and beverages (tea). This sets the stage

  16. Asian migration to Australia: food and health consequences.

    Science.gov (United States)

    Wahlqvist, Mark L

    2002-01-01

    Australia's food and health patterns are inextricably and increasingly linked with Asia. Indigenous Australians arrived in the continent via Asia and have linguistic connections with people who settled in south India; there was interaction and food trade between both South-East Asia and China and northern indigenous Australians over thousands of years. After European settlement in 1788, there have been several and increasing (apart from the period of the infamous White Australian Policy following the Colonial period and Independence, with Federation, in 1901) waves of Asian migration, notably during the gold rush (Chinese), the building of the overland Telegraph (Afghans), the Colombo Plan and Asian student education in Australia from the 1950s onwards (South-Eeast Asians), and with refugees (Vietnamese and mainland Chinese), and business (late twentieth century) and progressive family reunion. Each wave has injected additional food cultural elements and caused a measure of health change for migrants and host citizens. Of principal advantage to Australia has been the progressive diversification of the food supply and associated health protection. This has increased food security and sustainability. The process of Australian eating patterns becoming Asianized is evident through market garden development (and the introduction of new foods), fresh food markets and groceries, restaurants and the development of household cooking skills (often taught by student boarders). Most of the diversification has been with grain (rice), legumes (soy), greens, root vegetables, and various 'exotic fruits'. Food acculturation with migration is generally bi-directional. Thus, for Asians in Australia, there has been a decrease in energy expenditure (and a lower plane of energy throughput), an increase in food energy density (through increased fat and sugary drink intakes), and a decrease in certain health protective foods (lentils, soy, greens) and beverages (tea). This sets the stage

  17. Characterization of Interspecific Hybrids Between Oryza sativa L. and Three Wild Rice Species of China by Genomic In Situ Hybridization

    Institute of Scientific and Technical Information of China (English)

    Guang-Xuan Tan; Zhi-Yong Xiong; Hua-Jun Jin; Gang Li; Li-Li Zhu; Li-Hui Shu; Guang-Cun He

    2006-01-01

    In the genus Oryza, interspecific hybrids are useful bridges for transferring the desired genes from wild species to cultivated rice (Oryza sativa L.). In the present study, hybrids between O. sativa (AA genome)and three Chinese wild rices, namely O. rufipogon (AA genome), O. officinalis (CC genome), and O. meyeriana (GG genome), were produced. Agricultural traits of the F1 hybrids surveyed were intermediate between their parents and appreciably resembled wild rice parents. Except for the O. sativa × O. rufipogon hybrid,the other F1 hybrids were completely sterile. Genomic in situ hybridization (GISH) was used for hybrid verification. Wild rice genomic DNAs were used as probes and cultivated rice DNA was used as a block. With the exception of O. rufipogon chromosomes, this method distinguished the other two wild rice and cultivated rice chromosomes at the stage of mitotic metaphase with different blocking ratios. The results suggest that a more distant phylogenetic relationship exists between O. meyeriana and O. sativa and that O. rufipogon and O. sativa share a high degree of sequence homology. The average mitotic chromosome length of O. officinalis and O. meyeriana was 1.25- and 1.51-fold that of O. sativa, respectively. 4',6'-Diamidino2-phenylindole staining showed that the chromosomes of O. officinalis and O. meyeriana harbored more heterochromatin, suggesting that the C and G genomes were amplified with repetitive sequences compared with the A genome. Although chromocenters formed by chromatln compaction were detected with wild rice-specific signals corresponding to the C and G genomes in discrete domains of the F1 hybrid interphase nuclei, the size and number of O. meyeriana chromocenters were bigger and greater than those of O. officinalis. The present results provide an important understanding of the genomic relationships and a tool for the transfer of useful genes from three native wild rice species in China to cultivars.

  18. Detection and diagnosis of rice-infecting viruses

    Directory of Open Access Journals (Sweden)

    Tamaki Uehara Ichiki

    2013-10-01

    Full Text Available Rice-infecting viruses have caused serious damage to rice production in Asian, American, and African countries, where about 30 rice viruses and diseases have been reported. To control these diseases, developing accurate, quick methods to detect and diagnose the viruses in the host plants and any insect vectors of the viruses is very important. Based on an antigen–antibody reaction, serological methods such as latex agglutination reaction (LAR and enzyme-linked immunosorbent assay (ELISA have advanced to detect viral particles or major proteins derived from viruses. They aid in forecasting disease and surveying disease spread and are widely used for virus detection at plant protection stations and research laboratories. From the early 2000s, based on sequence information for the target virus, several other methods such as reverse transcription-polymerase chain reaction (RT-PCR and reverse transcription- loop-mediated isothermal amplification (RT-LAMP have been developed that are sensitive, rapid, and able to differentiate closely related viruses. Recent techniques such as real-time RT-PCR can be used to quantify the pathogen in target samples and monitor population dynamics of a virus, and metagenomic analyses using next-generation sequencing and microarrays show potential for use in the diagnosis of rice diseases.

  19. Mushroom Cultivation in South Korea

    OpenAIRE

    Mustafa Kemal Soylu; Mingu Kang

    2016-01-01

    Mushroom cultivation in South Korea is increasing fast last decades. Mushroom cultivation of South Korea is 173577 tones and South Korea gains 800 million dollars income annually. Different kind of mushroom species are cultivated and 31% enoki mushroom (Flammulina velutipes), 26% king oyster (Pleurotus eryngii), 26% oyster mushroom (Pleurotus ostreatus), 13% white buton mushroom (Agaricus bisporus) and 4% rest of the total mushroom Lentinula edodes, Ganoderma lucidum, Phellinus vb. are produc...

  20. Impacts of East Asian aerosols on the Asian monsoon

    Science.gov (United States)

    Bartlett, Rachel; Bollasina, Massimo; Booth, Ben; Dunstone, Nick; Marenco, Franco

    2016-04-01

    Over recent decades, aerosol emissions from Asia have increased rapidly. Aerosols are able to alter radiative forcing and regional hydroclimate through direct and indirect effects. Large emissions within the geographical region of the Asian monsoon have been found to impact upon this vital system and have been linked to observed drying trends. The interconnected nature of smaller regional monsoon components (e.g. the Indian monsoon and East Asian monsoon) presents the possibility that aerosol sources could have far-reaching impacts. Future aerosol emissions are uncertain and may continue to dominate regional impacts on the Asian monsoon. Standard IPCC future emissions scenarios do not take a broad sample of possible aerosol pathways. We investigate the sensitivity of the Asian monsoon to East Asian aerosol emissions. Experiments carried out with HadGEM2-ES use three time-evolving future anthropogenic aerosol emissions scenarios with similar time-evolving greenhouse gases. We find a wetter summer over southern China and the Indochina Peninsula associated with increased sulfate aerosol over China. The southern-flood-northern-drought pattern seen in observations is reflected in these results. India is found to be drier in the summer overall, although wetter in June. These precipitation changes are linked to the increase in sulfate through the alteration of large scale dynamics. Sub-seasonal changes are also seen, with an earlier withdrawal of the monsoon over East Asia.