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

    OpenAIRE

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

    2016-01-01

    Background Understanding population structure of the wild progenitor of Asian cultivated rice (O. sativa), the Oryza rufipogon species complex (ORSC), is of interest to plant breeders and contributes to our understanding of rice domestication. A collection of 286 diverse ORSC accessions was evaluated for nuclear variation using genotyping-by-sequencing (113,739 SNPs) and for chloroplast variation using Sanger sequencing (25 polymorphic sites). Results Six wild subpopulations were identified, ...

  3. Differentiation of a Miniature Inverted Transposable Element (MITE) System in Asian Rice Cultivars and Its Inference for a Diphyletic Origin of Two Subspecies of Asian Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In the present study, we report a survey on a Miniature Inverted Transposable Element (MITE) system known as mPing in 102 varieties of Asian cultivated rice (Oryza sativa L.). We found that mPing populations could be generalized into two families, mping-1 and mPing-2, according to their sequence structures. Further analysis showed that these two families of mPing had significant bias in their distribution pattern in two subspecies of rice, namely O. sativa ssp. japonica and indica. O. sativa japonica has a higher proportion of mPing-1 as a general trait, whereas O. sativa indica has a higher proportion of mPing-2. We also examined the mPing system in a doubled haploid (DH) cross-breeding population of jingxi 17 (japonica) and zhaiyeqing 8 (indica) varieties and observed that the mPing system was not tightly linked to major subspecies-determining genes.Furthermore, we checked the mPing system in 28 accessions of Asian common wild rice O. rufipogon and found the mPing system in O. rufipogon. The distribution pattern of the mping system in O. rufipogon indicated a diphyletic origin of the Asian cultivated rice O. sativa species. We did not find the mPing system in another 20 Oryza species. These results substantiated a previous hypothesis that O. rufipogon and O. nivara species were the closest relatives of O. sativa and that the two extant subspecies of O. sativa were evolved independently from corresponding ecotypes of O. rufipogon.

  4. 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.

  5. Gene tree discordance of wild and cultivated Asian rice deciphered by genome-wide sequence comparison.

    Science.gov (United States)

    Yang, Ching-chia; Sakai, Hiroaki; Numa, Hisataka; Itoh, Takeshi

    2011-05-15

    Although a large number of genes are expected to correctly solve a phylogenetic relationship, inconsistent gene tree topologies have been observed. This conflicting evidence in gene tree topologies, known as gene tree discordance, becomes increasingly important as advanced sequencing technologies produce an enormous amount of sequence information for phylogenomic studies among closely related species. Here, we aim to characterize the gene tree discordance of the Asian cultivated rice Oryza sativa and its progenitor, O. rufipogon, which will be an ideal case study of gene tree discordance. Using genome and cDNA sequences of O. sativa and O. rufipogon, we have conducted the first in-depth analyses of gene tree discordance in Asian rice. Our comparison of full-length cDNA sequences of O. rufipogon with the genome sequences of the japonica and indica cultivars of O. sativa revealed that 60% of the gene trees showed a topology consistent with the expected one, whereas the remaining genes supported significantly different topologies. Moreover, the proportions of the topologies deviated significantly from expectation, suggesting at least one hybridization event between the two subgroups of O. sativa, japonica and indica. In fact, a genome-wide alignment between japonica and indica indicated that significant portions of the indica genome are derived from japonica. In addition, literature concerning the pedigree of the indica cultivar strongly supported the hybridization hypothesis. Our molecular evolutionary analyses deciphered complicated evolutionary processes in closely related species. They also demonstrated the importance of gene tree discordance in the era of high-speed DNA sequencing.

  6. 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.

  7. 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.

  8. Origin, dispersal, cultivation and variation of rice.

    Science.gov (United States)

    Khush, G S

    1997-09-01

    There are two cultivated and twenty-one wild species of genus Oryza. O. sativa, the Asian cultivated rice is grown all over the world. The African cultivated rice, O. glaberrima is grown on a small scale in West Africa. The genus Oryza probably originated about 130 million years ago in Gondwanaland and different species got distributed into different continents with the breakup of Gondwanaland. The cultivated species originated from a common ancestor with AA genome. Perennial and annual ancestors of O. sativa are O. rufipogon and O. nivara and those of O. glaberrima are O. longistaminata, O. breviligulata and O. glaberrima probably domesticated in Niger river delta. Varieties of O. sativa are classified into six groups on the basis of genetic affinity. Widely known indica rices correspond to group I and japonicas to group VI. The so called javanica rices also belong to group VI and are designated as tropical japonicas in contrast to temperate japonicas grown in temperate climate. Indica and japonica rices had a polyphyletic origin. Indicas were probably domesticated in the foothills of Himalayas in Eastern India and japonicas somewhere in South China. The indica rices dispersed throughout the tropics and subtropics from India. The japonica rices moved northward from South China and became the temperate ecotype. They also moved southward to Southeast Asia and from there to West Africa and Brazil and became tropical ecotype. Rice is now grown between 55 degrees N and 36 degrees S latitudes. It is grown under diverse growing conditions such as irrigated, rainfed lowland, rainfed upland and floodprone ecosystems. Human selection and adaptation to diverse environments has resulted in numerous cultivars. It is estimated that about 120,000 varieties of rice exist in the world. After the establishment of International Rice Research Institute in 1960, rice varietal improvement was intensified and high yielding varieties were developed. These varieties are now planted to 70

  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. 基于线粒体基因片段核苷酸多态性的亚洲栽培稻起源进化研究%Study on the Origin and Evolution of Asian Cultivated Rice Based on Gene Fragment Nucleotides Diversity of Mitochondrial Genome

    Institute of Scientific and Technical Information of China (English)

    曹立荣; 魏鑫; 黄娟; 乔卫华; 张万霞; 杨庆文

    2013-01-01

    亚洲栽培稻的祖先是普通野生稻,已成为世界公认的观点,然而亚洲栽培稻的2个亚种:粳稻和籼稻是一次起源还是二次起源仍存在很大争议,其起源地是国内还是国外依然是国际学者间争论的焦点.本文通过对184份亚洲栽培稻和203份普通野生稻3段基因序列cox3、cox1、orf 224和2段基因间序列ssv-39/178、rps2-trnfM的多样性研究,验证了以下观点:1)粳稻起源于中国,籼稻起源于中国和国外;2)亚洲栽培稻的起源为二次起源,即普通野生稻存在偏籼和偏粳2种类型,亚洲栽培稻的2个亚种籼稻和粳稻在进化过程中分别由偏籼型的普通野生稻和偏粳型的普通野生稻进化而来.%Wild rice ( Oryza rufipogon ) has been recognized as the ancestor of Asian cultivated rice ( Oryza sati-va). However, where and how cultivated rice originated from wild rice has been debated for a long time in the world. Moreover,whether the two subspecies of Asian cultivated rice, indica and japonica, were domesticated with the ways of single origin or multiple origins was still considerably controversial, and whether they originated from China or aboard was still the focus of debate among international scholars. In this study, 184 accessions of Asian cultivated rice and 203 accessions of Oryza rufipogon to be sequenced with 3 gene fragments (cox3 ,coxl, orf 224) and two inter gene regions( ssv-39/178 ,rps2-trnfM) in mitochondrial genome of rice were collected. Through the study of gene diversity of the five fragments, the following propositions were verified. First,the origin of japonica was in China, and the origin of indica was not only in China but also in foreign countries. Second,the subspecies of Asian cultivated rice were domesticated with two origins. In other words,common wild rice contained the indica-like and japonica-like types, and the two subspecies were evolved from the indica -like wild rice and the japonica-like wild rice respectively.

  12. 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

    2016-06-28

    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.

  13. 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

  14. Insect pest management in tropical Asian irrigated rice.

    Science.gov (United States)

    Matteson, P C

    2000-01-01

    Abundant natural enemies in tropical Asian irrigated rice usually prevent significant insect pest problems. Integrated pest management (IPM) extension education of depth and quality is required to discourage unnecessary insecticide use that upsets this natural balance, and to empower farmers as expert managers of a healthy paddy ecosystem. Farmers' skill and collaboration will be particularly important for sustainable exploitation of the potential of new, higher-yielding and pest-resistant rice. IPM "technology transfer" through training and visit (T&V) extension systems failed, although mass media campaigns encouraging farmer participatory research can reduce insecticide use. The "farmer first" approach of participatory nonformal education in farmer field schools, followed by community IPM activities emphasizing farmer-training-farmer and research by farmers, has had greater success in achieving IPM implementation. Extension challenges are a key topic for rice IPM research, and new pest management technology must promote, rather than endanger, ecological balance in rice paddies.

  15. Chloroplast genome sequence confirms distinctness of Australian and Asian wild rice.

    Science.gov (United States)

    Waters, Daniel L E; Nock, Catherine J; Ishikawa, Ryuji; Rice, Nicole; Henry, Robert J

    2012-01-01

    Cultivated rice (Oryza sativa) is an AA genome Oryza species that was most likely domesticated from wild populations of O. rufipogon in Asia. O. rufipogon and O. meridionalis are the only AA genome species found within Australia and occur as widespread populations across northern Australia. The chloroplast genome sequence of O. rufipogon from Asia and Australia and O. meridionalis and O. australiensis (an Australian member of the genus very distant from O. sativa) was obtained by massively parallel sequencing and compared with the chloroplast genome sequence of domesticated O. sativa. Oryza australiensis differed in more than 850 sites single nucleotide polymorphism or indel from each of the other samples. The other wild rice species had only around 100 differences relative to cultivated rice. The chloroplast genomes of Australian O. rufipogon and O. meridionalis were closely related with only 32 differences. The Asian O. rufipogon chloroplast genome (with only 68 differences) was closer to O. sativa than the Australian taxa (both with more than 100 differences). The chloroplast sequences emphasize the genetic distinctness of the Australian populations and their potential as a source of novel rice germplasm. The Australian O. rufipogon may be a perennial form of O. meridionalis.

  16. Rice Crop Monitoring by Earth Observation Data in the Asian Region

    Science.gov (United States)

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

    2012-12-01

    Food security is a critical issue for the international community. In June 2011, the meeting of G20 agriculture ministers was held to discuss global food security and they agreed on an "Action Plan on Food Price Volatility and Agriculture". This plan includes a GEO Global Agricultural Monitoring (GEO-GLAM) initiative which utilizes remote sensing to improve projections of crop production and weather forecasting. Hence, satellite remote sensing is expected to contribute national, regional and global food security through the systematic and efficient collection of food security related information such as agro-meteorological condition, crop growth or yield estimation. Food security related information is utilized to take mitigation strategies or policies to manage food shortages or trading, and ensure food security. Especially in Asia, rice is the most important cereal crop because Asian countries are responsible for approximately 90% of the world rice productions and consumptions. There- fore, Asian countries are expected to contribute GLAM through the construction of rice crop monitoring system. We demonstrated the estimation of rice production, the crop phenology monitoring by Earth Observation (EO) data. The aim of this study is to establish a prototype system designed to provide paddy rice area and yield estimation. Generally, crop yield estimation is consist of two components, cultivated area and yield per area. The cultivated areas of paddy field are detected by the seasonal pattern of SAR data over paddy field. This means paddy field is filled with water just before planting rice, then covered by dense vegetation in growing season. The paddy filed map was derived from the seasonal Advanced Land Observation Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar (PALSAR) data with a simple threshold method. Then, to estimate rice productivity, we applied a simple rice crop model. The input data to the model are physical and chemical properties of

  17. Rice cultivation on floating-beds in different natural waters

    Institute of Scientific and Technical Information of China (English)

    SONGXiangfu; WUWeiming; JINGQianyu; YINGHuodong; ZHUMing; ZOUGuoyan

    1997-01-01

    Following the success in rice cultivation on floating-beds in natural water in 1990, the ecological adaptability of growing rice on floatingbeds was studied during the period of 1991-1993. Experiments were conducted in five different types of natural waters in Zhejiang Province from 28°35′ to 30°58′N and from 119°05′ to 121°11′E.

  18. 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.

  19. 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

  20. 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.

  1. Nutritional aspects of rice cultivation in Nyanza province, Kenya

    NARCIS (Netherlands)

    Niemeijer, R.

    1985-01-01

    Leiden [etc.] : African Studies Centre [etc.] (FNSP Report, no. 14), p. 156, 1985.Based on a survey conducted in 1984, the authors discuss the nutritional conditions prevailing among farming households engaged in irrigated rice cultivation in the Kano plain, Nyanza Province, Kenya. The survey covere

  2. 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

  3. 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.

  4. How to Evaluate the Rice Cultivation Suitability?

    Institute of Scientific and Technical Information of China (English)

    Wenxi; LI; Yueping; ZHANG; Changsong; WANG; Wei; MAO; Tianwen; HANG; Ming; CHEN; Bingning; ZHANG

    2013-01-01

    To rationally allocate farmland resources,and scientifically make farming industrial planning,we take Yizheng City in Jiangsu Province as the research object,and select 13 indicators.Based on Farmland Resources Management Information System in Yizheng City,we establish AHP model,and membership function model,for the evaluation of farmland suitability of rice.The results show that the farmland area in the highly suitable areas accounts for 10.2%of the total farmland area;the farmland area in the suitable areas accounts for 56.08%of the total farmland area;the farmland area in the marginally suitable areas accounts for 25.50%of the total farmland area;the farmland area in the unsuitable areas accounts for 8.22%of the total farmland area.There is significant positive correlation between the actual yield of rice surveyed and suitability index obtained through evaluation(R2=0.1964,319 samples);the actual yield of rice in the highly suitable areas is higher than in the marginally suitable areas and suitable areas,and the rice yield is the lowest in the unsuitable areas.

  5. 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

    2016-06-01

    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.

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

    OpenAIRE

    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...

  7. Genetic shift in local rice populations during rice breeding programs in the northern limit of rice cultivation in the world.

    Science.gov (United States)

    Fujino, Kenji; Obara, Mari; Ikegaya, Tomohito; Tamura, Kenichi

    2015-09-01

    The rapid accumulation of pre-existing mutations may play major roles in the establishment and shaping of adaptability for local regions in current rice breeding programs. The cultivated rice, Oryza sativa L., which originated from tropical regions, is now grown worldwide due to the concerted efforts of breeding programs. However, the process of establishing local populations and their origins remain unclear. In the present study, we characterized DNA polymorphisms in the rice variety KITAAKE from Hokkaido, one of the northern limits of rice cultivation in the world. Indel polymorphisms were attributed to transposable element-like insertions, tandem duplications, and non-TE deletions as the original mutation events in the NIPPONBARE and KITAAKE genomes. The allele frequencies of the KITAAKE alleles markedly shifted to the current variety types among the local population from Hokkaido in the last two decades. The KITAAKE alleles widely distributed throughout wild rice and cultivated rice over the world. These have accumulated in the local population from Hokkaido via Japanese landraces as the ancestral population of Hokkaido. These results strongly suggested that combinations of pre-existing mutations played a role in the establishment of adaptability. This approach using the re-sequencing of local varieties in unique environmental conditions will be useful as a genetic resource in plant breeding programs in local regions.

  8. 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.

  9. Effects of Phosphorus on Grain Quality of Upland and Paddy Rice under Different Cultivation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ya-jie; HUA Jing-jing; LI Ya-chao; CHEN Ying-ying; YANG Jian-chang

    2012-01-01

    We investigated how upland and paddy japonica rice responded to phosphorous (P) fertilizer under two cultivation methods.The upland rice Zhonghan 3 and the paddy rice Yangfujing 8 were both grown under moist cultivation (MC,control) and bare dry cultivation (DC) with three P levels,low (LP,45 kg/hm2),normal (NP,90 kg/hm2) and high (HP,135 kg/hm2).As P level increased,grain yields of both upland and paddy rice increased under DC.There were no significant differences in grain yields between HP and NP for either rice,although upland rice slightly increased and paddy rice slightly decreased in grain yield.Under DC at LP,Zhonghan 3 showed a higher head milled rice rate and better appearance,cooking and eating qualities than at HP or NP.Yangfujing 8 was similar to Zhonghan 3 except that Yangfujing 8 had better appearance quality at NP.Under MC,Zhonghan 3 had a higher head milled rice rate at LP and better cooking and eating qualities at NP.Yangfujing 8 was similar to Zhonghan 3 except in appearance quality.DC improved head milled rice rate and appearance quality of both upland and paddy rice,and cooking and nutrient qualities of paddy rice.Compared with paddy rice,upland rice had better processing,nutrient and eating qualities.The results suggest that upland and paddy rice respond differently to cultivation method and phosphorus level.

  10. 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.

  11. Effect of rice cultivation on malaria transmission in central Kenya.

    Science.gov (United States)

    Muturi, Ephantus J; Muriu, Simon; Shililu, Josephat; Mwangangi, Joseph; Jacob, Benjamin G; Mbogo, Charles; Githure, John; Novak, Robert J

    2008-02-01

    A 12-month field study was conducted between April 2004 and March 2005 to determine the association between irrigated rice cultivation and malaria transmission in Mwea, Kenya. Adult mosquitoes were collected indoors twice per month in three villages representing non-irrigated, planned, and unplanned rice agro-ecosystems and screened for blood meal sources and Plasmodium falciparum circumsporozoite proteins. Anopheles arabiensis Patton and An. funestus Giles comprised 98.0% and 1.9%, respectively, of the 39,609 female anophelines collected. Other species including An. pharoensis Theobald, An. maculipalpis Giles, An. pretoriensis Theobald, An. coustani Laveran, and An. rufipes Gough comprised the remaining 0.1%. The density of An. arabiensis was highest in the planned rice village and lowest in the non-irrigated village and that of An. funestus was significantly higher in the non-irrigated village than in irrigated ones. The human blood index (HBI) for An. arabiensis was significantly higher in the non-irrigated village compared with irrigated villages. For An. funestus, the HBI for each village differed significantly from the others, being highest in the non-irrigated village and lowest in the planned rice village. The sporozoite rate and annual entomologic inoculation rate (EIR) for An. arabiensis was 1.1% and 3.0 infective bites per person, respectively with no significant difference among villages. Sporozoite positive An. funestus were detected only in planned rice and non-irrigated villages. Overall, 3.0% of An. funestus samples tested positive for Plasmodium falciparum sporozoites. The annual EIR of 2.21 for this species in the non-irrigated village was significantly higher than 0.08 for the planned rice village. We conclude that at least in Mwea Kenya, irrigated rice cultivation may reduce the risk of malaria transmission by An. funestus but has no effect on malaria transmission by An. arabiensis. The zoophilic tendency of malaria vectors in irrigated areas

  12. 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.

  13. 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.

  14. Spread of herbicide-resistant weedy rice (red rice, Oryza sativa L.) after 5 years of Clearfield rice cultivation in Italy.

    Science.gov (United States)

    Busconi, M; Rossi, D; Lorenzoni, C; Baldi, G; Fogher, C

    2012-09-01

    The weedy relative of cultivated rice, red rice, can invade and severely infest rice fields, as reported by rice farmers throughout the world. Because of its close genetic relationship to commercial rice, red rice has proven difficult to control. Clearfield (Cl) varieties, which are resistant to the inhibiting herbicides in the chemical group AHAS (acetohydroxyacid synthase), provide a highly efficient opportunity to control red rice infestations. In order to reduce the risk of herbicide resistance spreading from cultivated rice to red rice, stewardship guidelines are regularly released. In Italy, the cultivation of Cl cultivars started in 2006. In 2010, surveillance of the possible escape of herbicide resistance was carried out; 168 red rice plants were sampled in 16 fields from six locations containing Cl and traditional cultivars. A first subsample of 119 plants was analysed after herbicide treatment and the resistance was found in 62 plants. Of these 119 plants, 78 plants were randomly selected and analysed at the level of the AHAS gene to search for the Cl mutation determining the resistant genotype: the Cl mutation was present in all the resistant plants. Nuclear and chloroplast microsatellite markers revealed a high correlation between genetic similarity and herbicide resistance. The results clearly show that Cl herbicide-resistant red rice plants are present in the field, having genetic relationships with the Cl variety. Finding plants homozygous for the mutation suggests that the crossing event occurred relatively recently and that these plants are in the F2 or later generations. These observations raise the possibility that Cl red rice is already within the cultivated rice seed supply.

  15. 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.

  16. 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 ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yongbo, E-mail: liuyb@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Liu, Fang [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wang, Chao [Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou 510380 (China); Quan, Zhanjun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Li, Junsheng, E-mail: lijsh@creas.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

    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. - Highlights: • We detect fusion Cry1Ab/1Ac proteins from Bt rice entering into aquatic ecosystems. • Bt-transgenic rice cultivation have no significant effect on zooplankton community. • Bt-transgenic rice cultivation have indirect effect on phytoplankton community. • Water quality explains the difference of plankton communities in adjacent ditches.

  18. 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

    Rice is a staple crop that has undergone substantial phenotypic and physiological changes during domestication. Here we resequenced the genomes of 40 cultivated accessions selected from the major groups of rice and 10 accessions of their wild progenitors (Oryza rufipogon and Oryza nivara) to >15 ...

  19. Identification of mildew resistance in wild and cultivated Central Asian grape germplasm

    OpenAIRE

    Riaz, Summaira; Boursiquot, Jean-Michel; Dangl, Gerald; Lacombe, Thierry; Laucou, Valerie; Tenscher, Alan C; Walker, M. Andrew

    2013-01-01

    Abstract Background Cultivated grapevines, Vitis vinifera subsp. sativa, evolved from their wild relative, V. vinifera subsp. sylvestris. They were domesticated in Central Asia in the absence of the powdery mildew fungus, Erysiphe necator, which is thought to have originated in North America. However, powdery mildew resistance has previously been discovered in two Central Asian cultivars and in Chinese Vitis species. ...

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

    Directory of Open Access Journals (Sweden)

    Mariano Isabela Orlando dos Santos

    2002-01-01

    Full Text Available 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 which were previously cultivated with beans. The experimental design was completely randomized, in a factorial scheme, using four soils, five P rates (75, 150, 300, 500 and 800 mg dm-3 and two liming treatments (with and without liming, with three replicates. After 60 days of flooding, soil samples were submitted to P extraction by Mehlich 1 and resin, and phosphorous fractionation. Two rice plants were cultivated in pots containing 3 dm³ of waterlogged soils. The labile P and the moderately labile P of the soils contributed for rice nutrition. The two tested extractors presented efficiency in the evaluation of P availability for the rice cultivated in lowland waterlogged soils.

  1. 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.

  2. The carbon count of 2000 years of rice cultivation

    NARCIS (Netherlands)

    Kalbitz, K.; Kaiser, K.; Fiedler, S.; Kölbl, A.; Amelung, W.; Bräuer, T.; Cao, Z.; Don, A.; Grootes, P.; Jahn, R.; Schwark, L.; Vogelsang, V.; Wissing, L.; Kögel-Knabner, I.

    2013-01-01

    More than 50% of the world's population feeds on rice. Soils used for rice production are mostly managed under submerged conditions (paddy soils). This management, which favors carbon sequestration, potentially decouples surface from subsurface carbon cycling. The objective of this study was to eluc

  3. 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.

  4. 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

  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. 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.

  7. Glycaemic and insulin responses, glycaemic index and insulinaemic index values of rice between three Asian ethnic groups.

    Science.gov (United States)

    Tan, V M H; Wu, T; Henry, C J; Lee, Y S

    2015-04-28

    Asians exhibit larger glycaemic response (GR) and insulin response (IR) than Caucasians, predisposing to an increased risk of type 2 diabetes mellitus (T2DM). We aimed to determine the GR and IR as well as the glycaemic index (GI) and insulinaemic index (II) of two rice varieties among three ethnic groups in Singapore. A total of seventy-five healthy males (twenty-five Chinese, twenty-five Malay and twenty-five Asian-Indians) were served the available equivalent carbohydrate amounts (50 g) of test foods (Jasmine rice and Basmati rice) and a reference food (glucose) on separate occasions. Postprandial blood glucose and plasma insulin concentrations were measured at fasting ( -5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min after food consumption. Using the trapezoidal rule, GR, IR, GI and II values were determined. The GR did not differ between ethnic groups for Jasmine rice and Basmati rice. The IR was consistently higher for Jasmine rice (P=0·002) and Basmati rice (P=0·002) among Asian-Indians, probably due to compensatory hyperinsulinaemia to maintain normoglycaemia. The GI and II of both rice varieties did not differ significantly between ethnicities. The overall mean GI for Jasmine rice and Basmati rice were 91 (sd 21) and 59 (sd 15), respectively. The overall mean II for Jasmine rice was 76 (sd 26) and for Basmati rice was 57 (sd 24). We conclude that the GI values presented for Jasmine rice and Basmati rice were applicable to all three ethnic groups in Singapore. Future studies should include deriving the II for greater clinical utility in the prevention and management of T2DM.

  8. On-farm trials with rice fish cultivation in the west Kano rice irrigation scheme, Kenya

    OpenAIRE

    Rasowo, J.; Auma, E.O.

    2006-01-01

    The viability of integrating rice farming with fish culture was studied in ten (10) rice plots. The on-farm research was done during one rice-growing season starting May 2003. The rice variety used was IR 2793-80-1 while the fish species was the Nile tilapia, Oreochromis niloticus. The fish culture period lasted 77 days. An average fish production of 132.4 kg/ha was obtained. The mean recovery rate of tilapia was 43 per cent. Total rice yield from the fields stocked with fish was lower than f...

  9. 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.

  10. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-03-01

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

  12. Little White Lies: Pericarp Color Provides Insights into the Origins and Evolution of Southeast Asian Weedy Rice

    Directory of Open Access Journals (Sweden)

    Yongxia Cui

    2016-12-01

    Full Text Available 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 rice, a multiple-origin model has been proposed based on neutral markers and analyses of domestication genes for hull color and seed shattering. Here, we examined variation in pericarp (bran color and its molecular basis to address how this trait evolved in Malaysian weeds and its possible role in weed adaptation. Functional alleles of the Rc gene confer proanthocyanidin pigmentation of the pericarp, a trait found in most wild and weedy Oryzas and associated with seed dormancy; nonfunctional rc alleles were strongly favored during rice domestication, and most cultivated varieties have nonpigmented pericarps. Phenotypic characterizations of 52 Malaysian weeds revealed that most strains are characterized by the pigmented pericarp; however, some weeds have white pericarps, suggesting close relationships to cultivated rice. Phylogenetic analyses indicate that the Rc haplotypes present in Malaysian weeds likely have at least three distinct origins: wild O. rufipogon, white-pericarp cultivated rice, and red-pericarp cultivated rice. These diverse origins contribute to high Rc nucleotide diversity in the Malaysian weeds. Comparison of Rc allelic distributions with other rice domestication genes suggests that functional Rc alleles may confer particular fitness benefits in weedy rice populations, for example, by conferring seed dormancy. This may promote functional Rc introgression from local wild Oryza populations.

  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. 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.

  15. Chloroplast genome sequence confirms distinctness of Australian and Asian wild rice

    OpenAIRE

    Waters, Daniel L. E.; Nock, Catherine J; Ishikawa, Ryuji; Rice, Nicole; Henry, Robert J.

    2012-01-01

    Cultivated rice (Oryza sativa) is an AA genome Oryza species that was most likely domesticated from wild populations of O. rufipogon in Asia. O. rufipogon and O. meridionalis are the only AA genome species found within Australia and occur as widespread populations across northern Australia. The chloroplast genome sequence of O. rufipogon from Asia and Australia and O. meridionalis and O. australiensis (an Australian member of the genus very distant from O. sativa) was obtained by massively pa...

  16. 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。

  17. Effects of screenhouse cultivation and organic materials incorporation on global warming potential in rice fields.

    Science.gov (United States)

    Xu, Guochun; Liu, Xin; Wang, Qiangsheng; Xiong, Ruiheng; Hang, Yuhao

    2017-03-01

    Global rice production will be increasingly challenged by providing healthy food for a growing population at minimal environmental cost. In this study, a 2-year field experiment was conducted to investigate the effects of a novel rice cultivation mode (screenhouse cultivation, SHC) and organic material (OM) incorporation (wheat straw and wheat straw-based biogas residue) on methane (CH4) and nitrous oxide (N2O) emissions and rice yields. In addition, the environmental factors and soil properties were also determined. Relative to the traditional open-field cultivation (OFC), SHC decreased the CH4 and N2O emissions by 6.58-18.73 and 2.51-21.35%, respectively, and the global warming potential (GWP) was reduced by 6.49-18.65%. This trend was mainly because of lower soil temperature and higher soil redox potential in SHC. Although the rice grain yield for SHC were reduced by 2.51-4.98% compared to the OFC, the CH4 emissions and GWP per unit of grain yield (yield-scaled CH4 emissions and GWP) under SHC were declined. Compared to use of inorganic fertilizer only (IN), combining inorganic fertilizer with wheat straw (WS) or wheat straw-based biogas residue (BR) improved rice grain yield by 2.12-4.10 and 4.68-5.89%, respectively. However, OM incorporation enhanced CH4 emissions and GWP, leading to higher yield-scaled CH4 emissions and GWP in WS treatment. Due to rice yield that is relatively high, there was no obvious effect of BR treatment on them. These findings suggest that apparent environmental benefit can be realized by applying SHC and fermenting straw aerobically before its incorporation.

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

    Science.gov (United States)

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

    2017-02-01

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

  19. Characteristics of High Quality Rice Xiang 5 and the Supporting Cultivation Techniques

    Institute of Scientific and Technical Information of China (English)

    Deze XU; Haiya CAI; Feng ZHAO; Jianping WU; Aiqing YOU

    2016-01-01

    The high quality rice,Xiang 5,is a new strain bred by Institute of Food Crops of Hubei Academy of Agricultural Sciences which first hybridizes Chinese scented rice with 9311,and then re-crosses it with Ezhong 5 for continuous generations. The strain has good quality,high yield,suitable maturity period,strong scent,strong combining ability and other features. This paper summarizes the appearance characteristics of Xiang 5 and main points of the supporting cultivation techniques,aimed at providing technical support and theoretical reference for its field production.

  20. 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.

  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. Distribution and identification of proteolytic Bacillus spp. in paddy field soil under rice cultivation.

    Science.gov (United States)

    Watanabe, K; Hayano, K

    1993-07-01

    Proteolytic bacteria in paddy field soils under rice cultivation were characterized and enumerated using azocoll agar plates. Bacillus spp. were the proteolytic bacteria that were most frequently present, comprising 59% of the isolates. They were always the numerically dominant proteolytic bacteria isolated from three kinds of fertilizer treatments (yearly application of rice-straw compost and chemical fertilizer, yearly application of chemical fertilizer, and no fertilizer application) and at three different stages of rice development (vegetative growth stage, maximal tillering stage, and harvest stage). Of the 411 proteolytic bacteria isolated, 124 isolates had stronger proteolytic activity than others on the basis of gelatin liquefaction tests and most of them were Bacillus spp. (100% in 1989 and 92.4% in 1991). Bacillus subtilis and Bacillus cereus were the main bacteria of this group and Bacillus mycoides, Bacillus licheniformis, and Bacillus megaterium were also present. We conclude that these Bacillus spp. are the primary source of soil protease in these paddy fields.

  3. 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.``

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Energy input-output analysis of rice cultivation in the coastal region of Bangladesh

    Directory of Open Access Journals (Sweden)

    Masudur Rahman

    2015-08-01

    Full Text Available An analysis of energy input-output in boro rice cultivation was undertaken for well recognized salinity classes (S1 -S5 and farm categories (landless, marginal, small, medium, and large in south-west coastal Bangladesh. A total of 125 target farmers were surveyed by using structured questionnaire during the boro season (January-May 2011. Survey data were converted into energy by using the respective energy co-efficient equivalents. The results revealed that the sequences of total energy input were S1 > S5 > S2 > S4 > S3 and medium > large > landless > small > marginal among salinity regimes and farm categories, respectively. The seedbed stage consumed the highest energy followed by growing stage, and harvesting and threshing. Inorganic fertilizers accounted for a major share (59.98% of energy input in rice field, while the lowest share was estimated for manpower (0.75%. Among fertilizers, nitrogen category was the most dominant source (54.94% of energy input following phosphate (3.82% and potassium (1.22%. The total output energy was in the sequences of S1 > S4 > S5 > S2 >S3 and landless > marginal > small > medium > large. Energy from main product (rice grains was higher than that of byproduct (straw. The study also found that total output energy decreases with increases in farm size. In case of energy efficiency (output-input ratio, S4 was found to be the most energy efficient (2.43 regime followed by S3, S1, S5 and S2, whereas marginal sized farmers were the most energy efficient (2.12 followed by landless, small, medium and large. This study shows that increased energy input in rice cultivation is not always necessary to get higher output energy in the salinity affected coastal Bangladesh. Therefore, it is necessary to practice environmentally sound management systems for sustainable rice production.

  10. Geographic description of genetic diversity and genetic relationships in the USDA Rice World Collection

    Science.gov (United States)

    Asian cultivated rice (Oryza sativa L.) is structured into five genetic groups, indica, AUS, tropical japonica, temperate japonica and aromatic. Genetic characterization of a global rice collection could help better serve the global research community. Collecting worldwide rice germplasm started in ...

  11. Genetic structure associated with diversity and geographic distribution in the USDA rice world collection

    Science.gov (United States)

    Asian cultivated rice (Oryza sativa L.) is structured into five genetic groups, indica, AUS, tropical japonica, temperate japonica and aromatic. Genetic characterization of a global rice collection could help better serve the global research community. Collecting worldwide rice germplasm started in ...

  12. 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

  13. Synthetic control of flowering in rice independent of the cultivation environment.

    Science.gov (United States)

    Okada, Ryo; Nemoto, Yasue; Endo-Higashi, Naokuni; Izawa, Takeshi

    2017-03-27

    For genetically homogeneous crops, the timing of flowering is determined largely by the cultivation environment and is strongly associated with the yield and quality of the harvest(1). Flowering time and other agronomical traits are often tightly correlated, which can lead to difficulty excluding the effects of flowering time when evaluating the characteristics of different genetic varieties(2). Here, we describe the development of transgenic rice plants whose flowering time can be controlled by specific agrochemicals. We first developed non-flowering rice plants by overexpressing a floral repressor gene, Grain number, plant height and heading date 7 (Ghd7)(3,4), to inhibit any environmentally induced spontaneous flowering. We then co-transformed plants with a rice florigen gene, Heading date 3a (Hd3a)(5), which is induced by the application of specific agrochemicals. This permitted the flowering time to be experimentally controlled regardless of the cultivation environment: some transgenic plants flowered only after agrochemical treatment. Furthermore, plant size and yield-related traits could, in some cases, be increased owing to both a longer duration of vegetative growth and an increased panicle size. This ability to control flowering time experimentally, independently of environmental variables, may lead to production of crops suitable for growth in different climates and facilitate breeding for various agronomical traits.

  14. 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

  15. Effect of Different Water Management and Nitrogen Forms on Characteristics of Iron Nutrition of Rice Cultivated Under Aerobic Condition

    Institute of Scientific and Technical Information of China (English)

    QIAN Xiao-qing; SHEN Qi-rong; WANG Juan-juan; YANG Jian-chang; ZHOU Ming-yao; BAI Yan-chao

    2003-01-01

    Although available iron is usually abundant for the growth of rice cultivated in waterlogged condition, the rice crop may suffer from its deficiency when cultivated in aerobic soil since the soil properties are totally different from waterlogged. Solubility of iron is very low in soils with high Eh and/or high Ph. A field experiment with five different depth (10, 20, 30, 40 and 50 cm) of groundwater, and a pot-experiment with five treatments of ammonium-nitrate ratio (100/0, 75/25, 50/50, 25/75 and 0/100) were conducted to study the characteristics of iron nutrition of rice in non-full irrigation condition. Moreover, the contents of iron extracted by 1 mol L-1 HCl of rice plant samples of 8 cultivars from both aerobic and waterlogged cultivation were analyzed to study the effect of water regimes on iron content of rice plants. The results were as follows: (1) The average content of available Fe (2.70 mg kg-1) of 5 layers of the soil treated with 10-cm depth of groundwater was significantly higher than that (0.83 mg kg-1) with 50-cm depth of groundwater, and the iron concentration of rice plant of the former was much higher than that of the later. (2) Iron deficiency of rice became much severe when high ratio of nitrate (more than 75 percent) in nitrogen fertilizer applied at different intervals in aerobic cultivation. (3) The iron concentrations of 3 cultivars, Wuyujing3 (99 mg kg-1), Yangdao4 (87 mg kg-1) and 9520 (95 mg kg-1), of rice plants cultivated in aerobic condition were significantly less than those(195, 197 and 175 mg kg-1) respectively in waterlogged condition at tillering stage. And even much significant differences existed in the iron concentrations of different cultivars growing in the aerobic and waterlogged condition at maturity.

  16. Genome wide association study (GWAS) for grain yield in rice cultivated under water deficit.

    Science.gov (United States)

    Pantalião, Gabriel Feresin; Narciso, Marcelo; Guimarães, Cléber; Castro, Adriano; Colombari, José Manoel; Breseghello, Flavio; Rodrigues, Luana; Vianello, Rosana Pereira; Borba, Tereza Oliveira; Brondani, Claudio

    2016-12-01

    The identification of rice drought tolerant materials is crucial for the development of best performing cultivars for the upland cultivation system. This study aimed to identify markers and candidate genes associated with drought tolerance by Genome Wide Association Study analysis, in order to develop tools for use in rice breeding programs. This analysis was made with 175 upland rice accessions (Oryza sativa), evaluated in experiments with and without water restriction, and 150,325 SNPs. Thirteen SNP markers associated with yield under drought conditions were identified. Through stepwise regression analysis, eight SNP markers were selected and validated in silico, and when tested by PCR, two out of the eight SNP markers were able to identify a group of rice genotypes with higher productivity under drought. These results are encouraging for deriving markers for the routine analysis of marker assisted selection. From the drought experiment, including the genes inherited in linkage blocks, 50 genes were identified, from which 30 were annotated, and 10 were previously related to drought and/or abiotic stress tolerance, such as the transcription factors WRKY and Apetala2, and protein kinases.

  17. 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.

  18. Effect of industrial by-products containing electron acceptors on mitigating methane emission during rice cultivation.

    Science.gov (United States)

    Ali, Muhammad Aslam; Lee, Chang Hoon; Kim, Sang Yoon; Kim, Pil Joo

    2009-10-01

    Three industrial by-products (fly ash, phosphogypsum and blast furnace slag), were evaluated for their potential re-use as soil amendments to reduce methane (CH(4)) emission resulting from rice cultivation. In laboratory incubations, CH(4) production rates from anoxic soil slurries were significantly reduced at amendment levels of 0.5%, 1%, 2% and 5% (wt wt(-1)), while observed CO(2) production rates were enhanced. The level of suppression in methane production was the highest for phosphogypsum, followed by blast slag and then fly ash. In the greenhouse experiment, CH(4) emission rates from the rice planted potted soils significantly decreased with the increasing levels (2-20 Mg ha(-1)) of the selected amendments applied, while rice yield simultaneously increased compared to the control treatment. At 10 Mg ha(-1) application level of the amendments, total seasonal CH(4) emissions were reduced by 20%, 27% and 25%, while rice grain yields were increased by 17%, 15% and 23% over the control with fly ash, phosphogypsum, and blast slag amendments, respectively. The suppression of CH(4) production rates as well as total seasonal CH(4) flux could be due to the increased concentrations of active iron, free iron, manganese oxides, and sulfate in the amended soil, which acted as electron acceptors and controlled methanogens' activity by limiting substrates availability. Among the amendments, blast furnace slag and fly ash contributed mainly to improve the soil nutrients balance and increased the soil pH level towards neutral point, but soil acidity was developed with phosphogypsum application. Conclusively, blast slag among the selected amendments would be a suitable soil amendment for reducing CH(4) emissions as well as sustaining rice productivity.

  19. Effects of Insect-Proof Net Cultivation, Rice-Duck Farming, and Organic Matter Return on Rice Dry Matter Accumulation and Nitrogen Utilization.

    Science.gov (United States)

    Liu, Xin; Xu, Guochun; Wang, Qiangsheng; Hang, Yuhao

    2017-01-01

    Insect-proof net cultivation (IPN), rice-duck farming (RD), and organic matter return (OM) are important methods to realize sustainable development of rice production. A split-plot field experiment was performed to study the effects of IPN, RD, and OM on the rice yield, dry matter accumulation and N utilization. Results showed that compared to inorganic N fertilizer (IN), wheat straw return, and biogas residue return increased the rice yield by 2.11-4.28 and 4.78-7.67%, respectively, and also improved dry matter and N accumulation after the elongation stage (EG), dry matter and N translocation, and N recovery efficiency (NRE). These results attributed to an increase in leaf SPAD values and net photosynthetic rate (Pn) after the EG. Compared to conventional rice farming (CR), RD promoted the rice yield by 1.52-3.74%, and contributed to higher the leaf photosynthesis, dry matter and N accumulation, dry matter and N translocation, and NRE. IPN decreased the intensity of sun radiation in the nets due to the coverage of the insect-proof nets, which declined the leaf Pn, dry matter accumulation and translocation, N absorption and translocation, and NRE compared to open field cultivation (OFC). The rice yield of IPN were 2.48-4.98% lower than that of OFC. Compared to the interaction between CR and IN, the interaction between RD and OM improved the rice yield by 5.26-9.33%, and increased dry matter and N accumulation after the EG, dry matter and N translocation, and NRE. These results indicated that OM, RD and the interaction between RD and OM could promote dry matter accumulation and N utilization, which was beneficial to improve the rice yield.

  20. Effects of Insect-Proof Net Cultivation, Rice-Duck Farming, and Organic Matter Return on Rice Dry Matter Accumulation and Nitrogen Utilization

    Science.gov (United States)

    Liu, Xin; Xu, Guochun; Wang, Qiangsheng; Hang, Yuhao

    2017-01-01

    Insect-proof net cultivation (IPN), rice-duck farming (RD), and organic matter return (OM) are important methods to realize sustainable development of rice production. A split-plot field experiment was performed to study the effects of IPN, RD, and OM on the rice yield, dry matter accumulation and N utilization. Results showed that compared to inorganic N fertilizer (IN), wheat straw return, and biogas residue return increased the rice yield by 2.11–4.28 and 4.78–7.67%, respectively, and also improved dry matter and N accumulation after the elongation stage (EG), dry matter and N translocation, and N recovery efficiency (NRE). These results attributed to an increase in leaf SPAD values and net photosynthetic rate (Pn) after the EG. Compared to conventional rice farming (CR), RD promoted the rice yield by 1.52–3.74%, and contributed to higher the leaf photosynthesis, dry matter and N accumulation, dry matter and N translocation, and NRE. IPN decreased the intensity of sun radiation in the nets due to the coverage of the insect-proof nets, which declined the leaf Pn, dry matter accumulation and translocation, N absorption and translocation, and NRE compared to open field cultivation (OFC). The rice yield of IPN were 2.48–4.98% lower than that of OFC. Compared to the interaction between CR and IN, the interaction between RD and OM improved the rice yield by 5.26–9.33%, and increased dry matter and N accumulation after the EG, dry matter and N translocation, and NRE. These results indicated that OM, RD and the interaction between RD and OM could promote dry matter accumulation and N utilization, which was beneficial to improve the rice yield. PMID:28174589

  1. 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.

  2. 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.

  3. 基于叶绿体基因多样性的中国水稻起源进化研究%Origin and Evolution of Cultivated Rice (O.sativa L.) in China Based on Gene Diversity of Chloroplast Genome

    Institute of Scientific and Technical Information of China (English)

    王荣升; 魏鑫; 曹立荣; 乔卫华; 张万霞; 杨庆文

    2011-01-01

    选择原产中国的98份亚洲栽培稻和125份普通野生稻为材料,对叶绿体中atpA序列、rps16内含子序列、trnP-rp133间隔区、trnG-trnfM序列、trnT-trnL间隔区序列的5段高突变序列进行测序,利用生物信息学方法进行比对分析,绘制Network网络图,构建系统发育树.结果表明,普通野生稻的Indel和SNP数目均比亚洲栽培稻多,序列多样性丰富;基于单倍型的Network网络图和系统发育树可将所有参试材料归为3个类群,类群Ⅰ主要为粳稻与普通野生稻,类群Ⅱ主要为籼稻,类群Ⅲ主要为普通野生稻,而类群Ⅱ和类群Ⅲ亲缘关系较近,提示粳、籼两个亚种可能由偏粳、偏籼的普通野生稻分别进化而来,支持二次起源学说;所有与亚洲栽培稻亲缘关系较近的普通野生稻均来源于华南地区,支持华南地区为我国亚洲栽培稻起源中心的论点.%To study the origin and evolution of Asian cultivated rice ( Oryza sativa L. ) ,98 accessions of Asian cultivated rice and 125 accessions of common wild rice {Oryza rufipogon) were selected for sequencing analysis. Through sequencing the atpA gene,rpsl6 intron,trnP-rpl33 inter spacer,trnG-trnfM inter spacer and trnT-trnL inter spacer in chloroplast genome in rice, the haplotype network and phylogenetic tree were made with bio-information software. The results showed that common wild rice had more Indels and SNPs compared with the Asian cultivated rice. Both the haplotype network and phylogenetic tree divided all test materials into three groups. Group I consisted by accessions from the Japonica subspecies and the common wild rice, Group II included mainly accessions of Indi-ca subspecies, while Group III were as the accessions of the common wild rice. Importantly, Group II and Group HI had a close relationship, which indicated that the Japonica and Indica Subspecies were originated from Japonica-like and Indica-like common wild rice separately, supporting the Double

  4. 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.

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

    Science.gov (United States)

    Khanh Van, Tran; Burja, Kurt; Thuy Nga, Tran; Kong, Kannitha; Berger, Jacques; Gardner, Michelle; Dijkhuizen, Marjoleine A; Hop, Le Thi; Tuyen, Le Danh; Wieringa, Frank T

    2014-09-01

    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 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 fortified rice (P rice was found to be highly acceptable in both countries. In Cambodia, schoolchildren consuming fortified rice had higher intakes than when consuming conventional rice (176 g/child/day and 168 g/child/day, respectively; P rice is acceptable in two countries in Southeast Asia. However, specific information is needed to explain the organoleptic qualities of fortified rice as perceived by end-users.

  6. 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

    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......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...

  7. Australian wild rice reveals pre-domestication origin of polymorphism deserts in rice genome.

    Directory of Open Access Journals (Sweden)

    Gopala Krishnan S

    Full Text Available BACKGROUND: Rice is a major source of human food with a predominantly Asian production base. Domestication involved selection of traits that are desirable for agriculture and to human consumers. Wild relatives of crop plants are a source of useful variation which is of immense value for crop improvement. Australian wild rices have been isolated from the impacts of domestication in Asia and represents a source of novel diversity for global rice improvement. Oryza rufipogon is a perennial wild progenitor of cultivated rice. Oryza meridionalis is a related annual species in Australia. RESULTS: We have examined the sequence of the genomes of AA genome wild rices from Australia that are close relatives of cultivated rice through whole genome re-sequencing. Assembly of the resequencing data to the O. sativa ssp. japonica cv. Nipponbare shows that Australian wild rices possess 2.5 times more single nucleotide polymorphisms than in the Asian wild rice and cultivated O. sativa ssp. indica. Analysis of the genome of domesticated rice reveals regions of low diversity that show very little variation (polymorphism deserts. Both the perennial and annual wild rice from Australia show a high degree of conservation of sequence with that found in cultivated rice in the same 4.58 Mbp region on chromosome 5, which suggests that some of the 'polymorphism deserts' in this and other parts of the rice genome may have originated prior to domestication due to natural selection. CONCLUSIONS: Analysis of genes in the 'polymorphism deserts' indicates that this selection may have been due to biotic or abiotic stress in the environment of early rice relatives. Despite having closely related sequences in these genome regions, the Australian wild populations represent an invaluable source of diversity supporting rice food security.

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

    OpenAIRE

    Van, T.K.; Burja, K.; Nga, T. T.; Kong, K.; Berger, Jacques; Gardner, M.(University of California, Davis, Davis, USA); Dijkhuizen, M. A.; Hop, L. T.; Tuyen, L. D.; Wieringa, Franck

    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 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 conv...

  9. 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.

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

    Science.gov (United States)

    Craig, Stephanie M; Reagon, Michael; Resnick, Lauren E; Caicedo, Ana L

    2014-01-01

    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.

  11. 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.

  12. Satellite-based investigation of flood-affected rice cultivation areas in Chao Phraya River Delta, Thailand

    Science.gov (United States)

    Son, N. T.; Chen, C. F.; Chen, C. R.; Chang, L. Y.

    2013-12-01

    The occurrence of catastrophic floods in Thailand in 2011 caused significant damage to rice agriculture. This study investigated flood-affected rice cultivation areas in the Chao Phraya River Delta (CRD) rice bowl, Thailand using time-series moderate resolution imaging spectroradiometer (MODIS) data. The data were processed for 2008 (normal flood year) and 2011, comprising four main steps: (1) data pre-processing to construct time-series MODIS vegetation indices (VIs), to filter noise from the time-series VIs by the empirical mode decomposition (EMD), and to mask out non-agricultural areas in respect to water-related cropping areas; (2) flood-affected area classification using the unsupervised linear mixture model (ULMM); (3) rice crop classification using the support vector machines (SVM); and (4) accuracy assessment of flood and rice crop mapping results. The comparisons between the flood mapping results and the ground reference data indicated an overall accuracy of 97.9% and Kappa coefficient of 0.62 achieved for 2008, and 95.7% and 0.77 for 2011, respectively. These results were reaffirmed by close agreement (R2 > 0.8) between comparisons of the two datasets at the provincial level. The crop mapping results compared with the ground reference data revealed that the overall accuracies and Kappa coefficients obtained for 2008 were 88.5% and 0.82, and for 2011 were 84.1% and 0.76, respectively. A strong correlation was also found between MODIS-derived rice area and rice area statistics at the provincial level (R2 > 0.7). Rice crop maps overlaid on the flood-affected area maps showed that approximately 16.8% of the rice cultivation area was affected by floods in 2011 compared to 4.9% in 2008. A majority of the flood-expanded area was observed for the double-cropped rice (10.5%), probably due to flood-induced effects to the autumn-summer and rainy season crops. Information achieved from this study could be useful for agricultural planners to mitigate possible impacts

  13. Changes in carbon stability and microbial activity in size fractions of micro-aggregates in a rice soil chronosequence under long term rice cultivation

    Science.gov (United States)

    Pan, Genxing; Liu, Yalong; Wang, Ping; Li, Lianqinfg; Cheng, Kun; Zheng, Jufeng; Zhang, Xuhui; Zheng, Jinwei; Bian, Rongjun; Ding, Yuanjun; Ma, Chong

    2016-04-01

    Recent studies have shown soil carbon sequestration through physical protection of relative labile carbon intra micro-aggregates with formation of large sized macro-aggregates under good management of soil and agricultural systems. While carbon stabilization had been increasingly concerned as ecosystem properties, the mechanisms underspin bioactivity of soil carbon with increased carbon stability has been still poorly understood. In this study, topsoil samples were collected from rice soils derived from salt marsh under different length of rice cultivation up to 700 years from eastern China. Particle size fractions (PSF) of soil aggregates were separated using a low energy dispersion protocol. Carbon fractions in the PSFs were analyzed either with FTIR spectroscopy. Soil microbial community of bacterial, fungal and archaeal were analyzed with molecular fingerprinting using specific gene primers. Soil respiration and carbon gain from amended maize as well as enzyme activities were measured using lab incubation protocols. While the PSFs were dominated by the fine sand (200-20μm) and silt fraction (20-2μm), the mass proportion both of sand (2000-200μm) and clay (content in the size fractions followed a similar trend to that of SOC. Bacterial and archaeal gene abundance was concentrated in both sand and clay fractions but that of fungi in sand fraction, and sharply decreased with the decreasing size of aggregate fraction. Gene abundance of archaeal followed a similar trend to that of bacterial but showing an increasing trend with prolonged rice cultivation in both sand and clay fractions. Change in community diversity with sizes of aggregate fractions was found of fungi and weakly of bacterial but not of archaeal. Soil respiration ratio (Respired CO2-C to SOC) was highest in silt fraction, followed by the fine sand fraction but lowest in sand and clay fractions in the rice soils cultivated over 100 years. Again, scaled by total gen concentration, respiration was

  14. Malaysian water footprint accounts: Blue and green water footprint of rice cultivation and the impact of water consumption in Malaysia

    Science.gov (United States)

    Fadillah, M. G. Nor; Marlia, M. H.

    2016-11-01

    Following water footprint approach, this study estimates the blue and green water consumption of rice cultivation in 11 states located in Peninsular Malaysia. The latter part evaluates the potential of water deprivation for freshwater resources in Malaysia. Climate data such as rainfall, temperature, humidity, sunshine and wind speed were used to calculate evapotranspiration rate and crop water use. The water footprint for cultivating rice was estimated for both main and off seasons range between 1600 m3/ton to 3300 m3/ton. The result of this study showed that the green water footprint is higher compared to the blue water footprint for both seasons. In conclusion, the potential water deprivation can be determined by integrating the water footprint and water stress index of different watersheds of Malaysia.

  15. 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

  16. 水稻高产创建栽培技术%High Yield and Create Cultivation Techniques of Rice

    Institute of Scientific and Technical Information of China (English)

    姜田英; 彭昌家

    2015-01-01

    This paper introduces the high yield and creates cultivation techniques of rice, such as the selection of seed, timely sowing, soil preparation,fertilization, specification transplanting, reasonable density planting, strengthen the man-agement of the field and timely harvest. To guide farmers to do scientific and reasonable rice super-high-yield strengthen-ing cultivation, improve the yield of rice and increase farmers' income, to ensure the rice production could continue to in-crease and ensure the safety of food production.%介绍了选用良种、适时播种、整好本田、配方施肥、规范移栽,合理密植、加强田间管理和适时收获等水稻高产创建栽培技术,旨在指导农民科学合理做好水稻超高产强化栽培,从而提高水稻单产,增加农民收益,确保水稻总产量持续增加,保障粮食生产安全。

  17. 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.

  18. 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.

  19. Microbial activity promoted with organic carbon accumulation in macroaggregates of paddy soils under long-term rice cultivation

    Science.gov (United States)

    Liu, Yalong; Wang, Ping; Ding, Yuanjun; Lu, Haifei; Li, Lianqing; Cheng, Kun; Zheng, Jufeng; Filley, Timothy; Zhang, Xuhui; Zheng, Jinwei; Pan, Genxing

    2016-12-01

    While soil organic carbon (SOC) accumulation and stabilization has been increasingly the focus of ecosystem properties, how it could be linked to soil biological activity enhancement has been poorly assessed. In this study, topsoil samples were collected from a series of rice soils shifted from salt marshes for 0, 50, 100, 300 and 700 years from a coastal area of eastern China. Soil aggregates were fractioned into different sizes of coarse sand (200-2000 µm), fine sand (20-200 µm), silt (2-20 µm) and clay (communities, soil respiration and enzyme activity. The results showed that the mass proportion both of coarse-sand (2000-200 µm) and clay (management. The finding here provides a mechanistic understanding of soil organic carbon turnover and microbial community succession at fine scale of soil aggregates that have evolved along with anthropogenic activity of rice cultivation in the field.

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

    OpenAIRE

    Maria Lígia de Souza Silva; Godofredo Cesar Vitti; Anderson Ricardo Trevizam

    2014-01-01

    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 re...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Formation of Guaiacol by Spoilage Bacteria from Vanillic Acid, a Product of Rice Koji Cultivation, in Japanese Sake Brewing.

    Science.gov (United States)

    Ito, Toshihiko; Konno, Mahito; Shimura, Yoichiro; Watanabe, Seiei; Takahashi, Hitoshi; Hashizume, Katsumi

    2016-06-08

    The formation of guaiacol, a potent phenolic off-odor compound in the Japanese sake brewing process, was investigated. Eight rice koji samples were analyzed, and one contained guaiacol and 4-vinylguaiacol (4-VG) at extraordinarily high levels: 374 and 2433 μg/kg dry mass koji, respectively. All samples contained ferulic and vanillic acids at concentrations of mg/kg dry mass koji. Guaiacol forming microorganisms were isolated from four rice koji samples. They were identified as Bacillus subtilis, B. amyloliquefaciens/subtilis, and Staphylococcus gallinarum using 16S rRNA gene sequence. These spoilage bacteria convert vanillic acid to guaiacol and ferulic acid to 4-VG. However, they convert very little ferulic acid or 4-VG to guaiacol. Nine strains of koji fungi tested produced vanillic acid at the mg/kg dry mass koji level after cultivation. These results indicated that spoilage bacteria form guaiacol from vanillic acid, which is a product of koji cultivation in the sake brewing process.

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

    Institute of Scientific and Technical Information of China (English)

    FU Jing; YANG Jian-chang

    2012-01-01

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

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. African rice (Oryza glaberrima) cultivation in the Togo Hills: ecological and socio-cultural cues in farmer seed selection and development

    NARCIS (Netherlands)

    Teeken, B.W.E.

    2015-01-01

    Abstract

    Teeken B (2015). African rice (Oryza glaberrima) cultivation in the Togo Hills: ecological and socio-cultural cues in farmer seed selection and development. PhD thesis, Wageningen University, The Netherlands, 306 pp. The low adoption rates of

  12. 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.

  13. An Investigation of Factors Affecting the Management of Risk for the Rice Cultivating Women in Sari Town with LISREL Application

    Directory of Open Access Journals (Sweden)

    M. charmchian Langerodi

    2016-03-01

    Full Text Available Introduction Agriculture relies on nature and farmers face environmental, social, financial and legal issues that makes farming to be consistently and strongly associated with risk. Agriculture can be considered to be the most risky economic venture. Ahmadi (1 listed several main sources of risk that farmers face. Economic risk includes price fluctuations for raw materials such as seed and fertilizer and for machinery at the pre-market delivery stage, difficulty obtaining bank credit and loans, price volatility for products in the post market delivery stage, inconsistent government policies for products and global fluctuations in the price of products. Social risk includes theft of crops, production and agricultural machinery and war. Nature-related risk includes natural disasters, climate change, agricultural pests and diseases. Market risk includes changes in the price of raw materials and products and increasing interest rates. Given that the range of agricultural activities having critical risk are diverse and the climate can vary widely, more sophisticated services are needed to meet the demands, cope with hazards and decrease risk. Understanding how women rice farmers deal with risk is essential for educators, and agriculture-related industries such as insurance, and policymakers. If the attitudes of these women towards risk are accurately recognized, risk management strategies, risk-related educational programs and risk strategies can be designed to meet their needs. The overallaim of this research isto investigate factors affecting risk management, and proposing and designing a model among rice cultivating women in Sari. Materials and Methods: The population of the study comprised 1677rice cultivating women in Sari of whom 248 were selected through stratified random sampling. A combination of quantitative, and descriptive-inferential statistics served as the methodology for the study and SPSS 16 and LISREL were applied for data analysis

  14. Study on Analysis of Variance on the indigenous wild and cultivated rice species of Manipur Valley

    Science.gov (United States)

    Medhabati, K.; Rohinikumar, M.; Rajiv Das, K.; Henary, Ch.; Dikash, Th.

    2012-10-01

    The analysis of variance revealed considerable variation among the cultivars and the wild species for yield and other quantitative characters in both the years of investigation. The highly significant differences among the cultivars in year wise and pooled analysis of variance for all the 12 characters reveal that there are enough genetic variabilities for all the characters studied. The existence of genetic variability is of paramount importance for starting a judicious plant breeding programme. Since introduced high yielding rice cultivars usually do not perform well. Improvement of indigenous cultivars is a clear choice for increase of rice production. The genetic variability of 37 rice germplasms in 12 agronomic characters estimated in the present study can be used in breeding programme

  15. 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.

  16. Effects of Soaking Cultivated Rice Seeds with Fulvic Acid on Physiological and Ecological Properties of Weedy Rice%黄腐植酸浸种栽培稻对杂草稻生理生态特性的影响

    Institute of Scientific and Technical Information of China (English)

    王晓琳; 尹书剑; 张卓亚; 张勇; 李贵

    2014-01-01

    Objective] This study aimed to investigate the effects of soaking cultivated rice seeds with fulvic acid (FA) on physiological and ecological properties of weedy rice in the direct seeding cultivated rice field. [Method] Weedy rice JS-Y1 and culti-vated rice Nanjing 44 were used as experimental materials for field plot trials to an-alyze the effects of soaking cultivated rice seeds with 0 (water as control), 4, 6, 8 g/L FA on til ering dynamics, plant height, chlorophyl content, photosynthetic perfor-mance, gas exchange parameters and yield components of weedy rice at different growth stages. [Result] Among the 4 plants/m2 weedy rice plots, with the increase of FA concentration, til er number, plant height, chlorophyl content, net photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of weedy rice were reduced. Under the 4-6 g/L FA concentration, til er numbers of weedy rice at differ-ent growth stages were reduced by 13.84%-35.71% compared with control at the same density and the most significant reduction was on the 22nd d after weedy rice germination; chlorophyl contents of weedy rice at the jointing stage were significant-ly reduced by 7.90%-8.88%. Furthermore, in the plots with 4 g/L FA, weedy rice plant heights at the heading stage and grain fil ing stage were significantly reduced by 6.37%-9.10%; Pn, Gs and Tr of weedy rice at the jointing stage and grain fil ing stage were significantly reduced by 10.19%-16.05%, 12.57%-23.33% and 10.28%-19.76%, respectively; 1 000-grain weight, effective panicle number per plant and panicles weight per plant of weedy rice at the maturity stage were significantly re-duced by 3.19%, 21.21% and 27.27%, correspondingly. [Conclusion] In 4 plants/m2 weedy rice plots, because soaking cultivated rice seeds with 4 g/L FA could regu-late the growth and development of cultivated rice, the soaking with FA could change the ecological relationship between cultivated rice and weedy rice, affect weedy rice

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

    Science.gov (United States)

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

    2015-02-20

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

  18. 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.

  19. Complex evolution of S5, a major reproductive barrier regulator, in the cultivated rice Oryza sativa and its wild relatives.

    Science.gov (United States)

    Du, Hongyi; Ouyang, Yidan; Zhang, Chengjun; Zhang, Qifa

    2011-07-01

    • The hybrid sterility gene S5 comprises three types of alleles in cultivated rice. Such tri-allelic system provided a unique opportunity to study the molecular bases of evolutionary changes underlying reproductive isolation in plants. • We analysed the sequence diversity and evolutionary history of S5 in 138 Oryza accessions. We also examined the effect of the two functional variations (C819A and C1412T) in determining hybrid sterility by transformation. • Nineteen haplotypes were identified, which were classified into the indica-like, the japonica-like and the wide-compatibility gene (WCG)-like group, according to the sequence features of the tri-allelic system. The origin and evolutionary course of the three allelic groups were investigated, thus confirming the independent origins of indica and japonica subspecies. There were perfect associations between C819A and C1412T in the rice germplasm assayed, and the combination of C819 and C1412 was required for hybrid sterility. Evidence of positive selection in the WCG-like alleles suggested that they might have been favored by selection for higher compatibility in hybrids. • The complex evolution of S5 revealed the counteractive function of the three allelic groups at the species level. S5 might perform an important primary function in an evolutionary scale, and hybrid sterility acts as a 'byproduct' of this speciation gene.

  20. 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.

  1. Long-term rice cultivation stabilizes soil organic carbon and promotes soil microbial activity in a salt marsh derived soil chronosequence.

    Science.gov (United States)

    Wang, Ping; Liu, Yalong; Li, Lianqing; Cheng, Kun; Zheng, Jufeng; Zhang, Xuhui; Zheng, Jinwei; Joseph, Stephen; Pan, Genxing

    2015-10-27

    Soil organic carbon (SOC) sequestration with enhanced stable carbon storage has been widely accepted as a very important ecosystem property. Yet, the link between carbon stability and bio-activity for ecosystem functioning with OC accumulation in field soils has not been characterized. We assessed the changes in microbial activity versus carbon stability along a paddy soil chronosequence shifting from salt marsh in East China. We used mean weight diameter, normalized enzyme activity (NEA) and carbon gain from straw amendment for addressing soil aggregation, microbial biochemical activity and potential C sequestration, respectively. In addition, a response ratio was employed to infer the changes in all analyzed parameters with prolonged rice cultivation. While stable carbon pools varied with total SOC accumulation, soil respiration and both bacterial and fungal diversity were relatively constant in the rice soils. Bacterial abundance and NEA were positively but highly correlated to total SOC accumulation, indicating an enhanced bio-activity with carbon stabilization. This could be linked to an enhancement of particulate organic carbon pool due to physical protection with enhanced soil aggregation in the rice soils under long-term rice cultivation. However, the mechanism underpinning these changes should be explored in future studies in rice soils where dynamic redox conditions exist.

  2. Unraveling the rich phenotypic and genetic diversity in rice for varietal improvement

    Science.gov (United States)

    Asian cultivated rice (Oryza sativa L.) has two distinct varietal groups identified as the indica and japonica subspecies. With the advent of molecular markers the indica subspecies was divided into the indica and aus subpopulation groups and the japonica subspecies into the aromatic, tropical japon...

  3. 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

  4. Uncertainties in the national inventory of methane emissions from rice cultivation: field measurements and modeling approaches

    Science.gov (United States)

    Zhang, Wen; Sun, Wenjuan; Li, Tingting

    2017-01-01

    Uncertainties in national inventories originate from a variety of sources, including methodological failures, errors, and insufficiency of supporting data. In this study, we analyzed these sources and their contribution to uncertainty in the national inventory of rice paddy methane emissions in China and compared the differences in the approaches used (e.g., direct measurements, simple regressions, and more complicated models). For the 495 field measurements we collected from the scientific literature, the area-weighted 95 % CI (confidence interval) ranged from 13.7 to 1115.4 kg CH4 ha-1, and the histogram distribution of the measurements agreed well with parameterized gamma distributions. For the models, we compared the performance of methods of different complexity (i.e., the CH4MOD model, representing a complicated method, and two less complex statistical regression models taken from literature) to evaluate the uncertainties associated with model performance as well as the quality and accessibility of the regional datasets. Comparisons revealed that the CH4MOD model may perform worse than the comparatively simple regression models when no sufficient input data for the model is available. As simulated by CH4MOD with data of irrigation, organic matter incorporation, and soil properties of rice paddies, the modeling methane fluxes varied from 17.2 to 708.3 kg CH4 ha-1, covering 63 % of the range of the field measurements. When applying the modeling approach to the 10 km × 10 km gridded dataset of the model input variables, the within-grid variations, made via the Monte Carlo method, were found to be 81.2-95.5 % of the grid means. Upscaling the grid estimates to the national inventory, the total methane emission from the rice paddies was 6.43 (3.79-9.77) Tg. The fallacy of CH4MOD contributed 56.6 % of the total uncertainty, with the remaining 43.4 % being attributed to errors and the scarcity of the spatial datasets of the model inputs. Our analysis reveals the

  5. 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.

  6. Two new loci for hybrid sterility in cultivated rice (Oryza sativa L.).

    Science.gov (United States)

    Wan, J; Yamaguchi, Y; Kato, H; Ikehashi, H

    1996-02-01

    Female gamete abortion in Indica-Japonica crosses of rice was earlier identified to be due to an allelic interaction at the S-5 locus on chromosome 6. Recently, in other crosses of rice, similar allelic interactions were found at loci designated as S-7 and S-8, located on chromosomes 7 and 6 respectively. All of them are independent of each other. At the S-5 locus, Indica and Japonica rice have S-5 (i) and S-5 (j) alleles respectively and Javanicas, such as Ketan Nangka, have a neutral allele S-5 (n) .The S-5 (i) /S-5 (j) genotype is semi-sterile due to partial abortion of female gametes carrying S-5 (j) , but both the S-5 (n) /S-5 (i) and S-5 (n) /S-5 (j) genotypes are fertile. The S-5 (n) allele is thus a "wide-compatibility gene" (WCG), and parents homozygous for this allele are called wide-compatible varieties (WCV). Such parents when crossed with Indica or Japonica varieties do not show F1 hybrid sterility. Wide-compatible parents have been used to overcome sterility barriers in crosses between Indica and Japonica rice. However, a Javanica variety, Ketan Nangka (WCV), showed typical hybrid sterility when crossed to the Indian varieties N22 and Jaya. Further, Dular, another WCV from India, showed typical hybrid sterility when crossed to an IRRI line, IR2061-628-1-6-4-3(IR2061-628). By genetic analyses using isozyme markers, a new locus causing hybrid sterility in crosses between Ketan Nangka and the Indicas was located near isozyme loci Est-1 and Mal-1 on chromosome 4, and was designated as S-9. Another new locus for hybrid sterility in the crosses between Dular and the IR2061-628 was identified and was found linked to four isozyme loci, Sdh-1, Pox-2, Acp-1 and Acp-2, on chromosome 12. It was designated as S-15. On the basis of allelic interactions causing female-gamete abortion, two alleles were found at S-9, S-9 (kn) in Ketan Nangka and S-9 (i) in N22 and Jaya. In the heterozygote, S-9 (kn) /S-9 (i) , which was semisterile, female gametes carrying S-9 (kn

  7. 水稻梯式栽培下野鸡野鸭生态种养设计与思考%Designs of Rice-pheasant-mallard Complex Ecosystem under Rice Terrace Cultivation Model and Its Thoughts

    Institute of Scientific and Technical Information of China (English)

    郑华斌; 高文娟; 扈婷; 陈杨; 龙攀; 黄璜

    2011-01-01

    This paper proposes one type of rice-pheasant-mallard complex ecological planting and breeding technique of under rice terrace cultivation model, which can carry out rice terrace cultivation and realize water storage in ditch and dry-wet alternation infiltrating irrigation in ridging. The cultivation model opens living space for pheasants and mallards, the former acts and predates on the ridge, and the latter plays and predates in the ditch. So, this cultivation model can reduce water consumption of rice-duck complex ecosystem, methane emission in paddy field due to long time flooded* amount of pesticides, and chemical fertilizers due to the stalks of manure which can reduce environmental pollution. In general. Rice-pheasant-mallard complex ecological planting and breeding technique of under rice terrace cultivation model can realize higher economic benefits, social benefits and ecological benefit than other ecological planting and breeding model.%提出了一种水稻梯式栽培下野鸡野鸭生态种养技术.通过改变传统的水稻生产模式,实行水稻梯式栽培,实现垄沟蓄水,垄上半浸润式灌溉,从而为野鸡的生长活动开辟空间,野鸡在垄上活动和捕食,野鸭在垄沟游戏和捕食,最终减少稻田养鸭的耗水量,降低由于长期淹水的稻田甲烷排放量,减少农药的使用量.同时鸡鸭粪还田能减少肥料的施用量,降低由于大量施用化肥造成的环境污染.水稻梯式栽培下鸡鸭生态种养技术的经济效益、社会效益和生态效益明显高于其他生态种养模式.

  8. 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.

  9. 江淮丘陵区旱稻栽培技术探讨%Discussion on Cultivation Techniques of Upland Rice in Hilly Area of Jianghuai

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    旱稻具有抗旱性较强的生理特性。从播前准备、适时播种、水肥管理和病虫害防治等方面对江淮丘陵旱稻高产栽培技术进行了介绍,为该区旱稻生产提供了技术借鉴。%Upland rice had a physiological characteristic of strong drought resistance. The cultivation techniques of upland rice in hilly area of Jianghuai were introduced from the following aspects, including preparation before sowing, sowing, fertilizer management and pest control and others. The results provided technical references for upland rice production.

  10. 册亨县水稻覆膜直播栽培试验%Experiment of Plastic Film Mulching Cultivation by Direct Seeding of Rice in Ceheng County

    Institute of Scientific and Technical Information of China (English)

    黄如泽

    2014-01-01

    册亨县水稻覆膜直播栽培试验研究结果表明,地膜覆盖直播栽培能耐干旱、没有杂草、病虫害少,只是开始时用工较多,但整体上分析,覆膜直播比旱育稀植移栽的效果好。%The results of experiment of plastic film mulching cultivation by direct seeding of rice in Ceheng County showed that plastic film mulching cultivation by direct seeding had drought tolerance,no weeds,fewer pests and diseases,just the employment was more at the beginning,but on the whole,plastic film mulching cultivation by direct seeding had better effect than dry nursery and sparse planting transplant.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. Complete Genomic Structure of the Cultivated Rice Endophyte Azospirillum sp. B510

    Science.gov (United States)

    Kaneko, Takakazu; Minamisawa, Kiwamu; Isawa, Tsuyoshi; Nakatsukasa, Hiroki; Mitsui, Hisayuki; Kawaharada, Yasuyuki; Nakamura, Yasukazu; Watanabe, Akiko; Kawashima, Kumiko; Ono, Akiko; Shimizu, Yoshimi; Takahashi, Chika; Minami, Chiharu; Fujishiro, Tsunakazu; Kohara, Mitsuyo; Katoh, Midori; Nakazaki, Naomi; Nakayama, Shinobu; Yamada, Manabu; Tabata, Satoshi; Sato, Shusei

    2010-01-01

    We determined the nucleotide sequence of the entire genome of a diazotrophic endophyte, Azospirillum sp. B510. Strain B510 is an endophytic bacterium isolated from stems of rice plants (Oryza sativa cv. Nipponbare). The genome of B510 consisted of a single chromosome (3 311 395 bp) and six plasmids, designated as pAB510a (1 455 109 bp), pAB510b (723 779 bp), pAB510c (681 723 bp), pAB510d (628 837 bp), pAB510e (537 299 bp), and pAB510f (261 596 bp). The chromosome bears 2893 potential protein-encoding genes, two sets of rRNA gene clusters (rrns), and 45 tRNA genes representing 37 tRNA species. The genomes of the six plasmids contained a total of 3416 protein-encoding genes, seven sets of rrns, and 34 tRNAs representing 19 tRNA species. Eight genes for plasmid-specific tRNA species are located on either pAB510a or pAB510d. Two out of eight genomic islands are inserted in the plasmids, pAB510b and pAB510e, and one of the islands is inserted into trnfM-CAU in the rrn located on pAB510e. Genes other than the nif gene cluster that are involved in N2 fixation and are homologues of Bradyrhizobium japonicum USDA110 include fixABCX, fixNOQP, fixHIS, fixG, and fixLJK. Three putative plant hormone-related genes encoding tryptophan 2-monooxytenase (iaaM) and indole-3-acetaldehyde hydrolase (iaaH), which are involved in IAA biosynthesis, and ACC deaminase (acdS), which reduces ethylene levels, were identified. Multiple gene-clusters for tripartite ATP-independent periplasmic-transport systems and a diverse set of malic enzymes were identified, suggesting that B510 utilizes C4-dicarboxylate during its symbiotic relationship with the host plant. PMID:20047946

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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...

  7. 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

  8. Prevalence, isolation and characterization of Bacillus cereus strains from rice of local cultivators of Sabah, Sarawak, and Peninsular Malaysia

    Science.gov (United States)

    Sawei, Jelin; Sani, Norrakiah Abdullah

    2016-11-01

    Bacillus cereus is a spore-forming, facultative anaerobic, motile microorganism that has been identified as a causative agent of two types of gastrointestinal diseases such as emetic and diarrhea. This foodborne pathogen is found in both vegetative cells and endospores form in foods such as rice either raw or cooked. The aim of this study is to investigate and determine the prevalence, characterize and identify the isolation of vegetative cells and endospores of B. cereus in thirty varieties (n=3) of raw rice from Sabah, Sarawak and Peninsular Malaysia. A total of 90 (n=90) raw rice were examined and 84 (93.33%) samples were positive to vegetative cells of B. cereus. However, only 32 (35.56%) samples were positive for endospore cells that able to germinate after samples were heated at 75°C for 15 mins. The mean log cfu/g for vegetative cells were higher range (0.00 - 4.1533) than visible endospores (0.00 - 3.7533 mean log cfu/g). Sample of raw red rice (UKMRC9) had significantly higher contamination by both vegetative cells and endospores at p<0.05, than the other raw rice samples.

  9. Paddy Rice Identification by Blending Time-series SAR and Optical Data

    Science.gov (United States)

    Oyoshi, K.; Sobue, S.

    2014-12-01

    In Asia, rice is a staple cereal crop and Asian countries are responsible for approximately 90% of the world rice production and consumption. Asian space and agriculture related agencies launched an Asia-Rice Crop Estimation & Monitoring (Asia-RiCE) component for the GEOGLAM initiative. However, there are some difficulties to monitor rice crop by satellite imagery, which is different from other crops: 1) rice is mainly cultivated in rainy season and a large amount of cloud cover limits rice crop monitoring by the optical sensors; 2) adequate rainfall and temperature enable to cultivate rice two or three times a year in the tropics; 3) each field size is small compared to croplands in Western countries; and 4) water related agricultural disasters such as flood and drought are frequently occurred. To overcome these issues, C-band backscattering coefficient from RADARSAT-2 and reflectance data from MODIS were blended to estimate rice planted area over the West Java, Indonesia. By blending SAR and optical data, roughness and spectral information can be effectively used to differentiate paddy rice from other landcovers. The methodology using multi-wavelength data including optical (visible to thermal infrared) and SAR (X/C/L) would be a promising way for monitoring paddy rice in terms of the accuracy improvement and also the operational use to meet the requirement of observing the whole country with high-revisit frequency. In particular, the combining C-band SAR with other frequency SAR data such as L-band SAR onboard the ALOS-2 would be a challenge.

  10. 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

  11. 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.

  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. 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

  14. 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.

  15. Comparative Study of Rice Morphogenesis with Different Cultivation Methods%不同栽培方式下水稻形态发生比较研究

    Institute of Scientific and Technical Information of China (English)

    严定春

    2012-01-01

    The aim of this study was to compare the morphological characteristics of rice ( Oryza sativa L. ) with different cultivation methods and investigate the dynamics of organ growth and development characteristics of different rice cultivars. [ 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 a-mong 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 can be described with the equations y -ax 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 methods; the relationship between plant height and sunshine duration, plant height and GDD (growing degree days) can be described with the equation y = ax + b, 19.23 ℃ o d of GDD ( ≥ 10℃ o 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 japonica rice cultivars, but the specific leaf weight and leaf angle were smaller. .[ Conclusion ] Comparison of morphological characteristic differences 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 selection of water

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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。

  1. Preliminary Study on Mechanized Cultivation Technologies of Male Parent in Indica-Japonica Hybrid Rice Seed Production%籼粳杂交水稻制种父本机插机收技术初探

    Institute of Scientific and Technical Information of China (English)

    陆惠斌; 马寅超

    2016-01-01

    The paper introduced the trials and demonstration of male parent machine transplanting and machine harvesting in indica-japonica hybrid rice seed production in Ningbo City about four years. The costs and seed yield of male parent with different cultivation method were analyzed, and put forward the mechanized cultivation techniques of male parent in indica-japonica hybrid rice seed pro-duction.%介绍了宁波市4年来籼粳杂交水稻制种父本机插机收的试验示范情况,分析比较了父本机插机收与人工插种收割的成本和制种产量,提出了杂交水稻父本机插机收的配套栽培技术。

  2. 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.

  3. 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.

  4. 旱作条件下旱稻和水稻叶片光合特性及RuBP羧化酶活性的比较%Comparison of photosynthetic characteristics and RuBPcase activity between upland rice and rice in leaves under dry cultivation

    Institute of Scientific and Technical Information of China (English)

    陈展宇; 徐克章; 吴磊; 张治安; 凌凤楼

    2012-01-01

    [Objective] The study was performed to explore changes of photosynthetic characteristics and RuBPcase activity in leaves of uplan rice varieties and rice varieties under dry cultivation condition. The purpose was to provide physiological basis for uplan rice varieties breeding and high-yield cultivation. [Method] With two uplan rice varieties(Han 9710, Qinai)and two rice varieties(Jinong No. 8, Changbai No. 12)as experimentals materials, photosynthetic characteristics and RuBPcase activity at seedling stage, flowering stage,filling stage and maturation stage were measured under dry cultivation. [Result] Under dry cultivation, the contents of chlorophyll, net photosynthetic rate(Pn) and RuBPcase activity of leaves in upland rice varieties during different durations were significantly(P〈0.05) higher than those in rice varieties. Transpiration rate(Tr) of leaf in upland rice varieties was significantly(P〈0.05)lower than that in rice varieties,and utilization efficiency of water(WUE) of upland rice varieties was very significantly(P〈 0.01) higher than that in rice varieties. The net Pn of uplan rice varieties showed significantly positive correlation with stomatal conductance(Gs) ,WUE and RuBPcase activity. [Conclusion] Compared with rice varieties leaves of upland rice varieties have contents of chlorophyll, strong activity of RuBPcase, weak transpiration and increasing WUE, which make for enhancing the drought resistance of upland rice and maintain higer photosynthetic efficiency.%【目的】探讨旱作条件下旱稻、水稻品种叶片光合特性及RuBP羧化酶活性的变化规律,为旱稻品种的选育和高产栽培提供依据。【方法】选择2个旱稻品种("旱9710"、"秦爱")和2个水稻品种("吉农8号"、"长白12号")为试验材料进行田间旱作试验,于苗期、开花期、灌浆期、成熟期测定其叶片光合特性及RuBP羧化酶活性。【结果】旱作条

  5. Detection of Distorted Segregation in Genotype of Pollen Calli Derived from Hybrid F1 of Cultivated Rice (Oryza sativa L.) Using SSR Markers

    Institute of Scientific and Technical Information of China (English)

    YAO Yan; LU Yong-gen; LIU Xiang-dong; FENG Jiu-huan; ZHANG Gui-quan

    2006-01-01

    S-a, S-b and S-c are three loci for F1 pollen sterility in cultivated rice (Oryza sativa L.). Taichung 65 (T65) is all Sj/Sj at these three loci, while its F1 pollen sterile near-isogenic lines, TISL2 (S-b), TISL4 (S-a) and TISL5 (S-c) is Si/Si according to their respective sterility locus. Using SSR molecular marker to detect the segregation of the allele Si and Sj in pollen calli population induced from different hybrid F1, which have different pollen sterility locus, showed that the segregation of allele Si and Sj was distorted. The distorted direction of pollen calli population in vitro was not the same as F2 population in vivo. The quantities of pollen callus carrying Sj were much more than that of carrying Si at S-a and S-c locus, the ratio of Si and Sj were 1:4.81 and 1:1.96 respectively. But the opposite tendency was observed at S-b locus, the ratio of Si and Sj being 1:0.35. At the same time, all these results were undisturbed by either culture medium or culture period.

  6. High-yielding cultivation techniques of ratooning rice in Changting county%长汀县再生稻丰产栽培技术

    Institute of Scientific and Technical Information of China (English)

    黄玉娥

    2011-01-01

    通过两年千亩再生稻示范,总结出一套再生稻丰产栽培技术。主要技术环节包括选用高产优质、再生力强品种;掌握播种期控制秧龄、适当早插;配方施肥、水分管理增强根系活力;合理留桩促进再生芽生长;及时防治病虫害。%Ratooning rice was planted in 66.7hm2 demonstration field in Changting for two years, a set of high-yielding cultivation techniques were summarized. The techniques included the selection of varieties with traits of high quality and strong regenerative ability, timely sowing and adjusting seedling age, appropriately early transplanting, fomula fertilization and water management to strengthen the vigor of root system, maintaining suitalbe stubble height for promoting the development of regenerated buds, disease and oest control.

  7. 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

  8. 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 (psystem. Measurements of soil organic carbon contents before and three years after introduction of upland crop rotations indicated a SOC loss for the R-M system, while for the other

  9. Cultivation, identification and quantification of one species of yeast-like symbiotes, Candida, in the rice brown planthopper, Nilaparvata lugens

    Institute of Scientific and Technical Information of China (English)

    Kun Pang; Sheng-Zhang Dong; Yun Hou; Ya-Lin Bian; Ke Yang; Xiao-Ping Yu

    2012-01-01

    The brown planthopper (BPH),Nilaparvata lugens St(a)l,which is one of the most destructive pests of rice,has been confirmed to harbor yeast-like symbiotes (YLS) in the fat body.Several morphologically different YLS have been previously isolated and cultured in vitro from BPH,but direct evidence is lacking to further clarify whether the cultured YLS were from BPH.In this study,one species of YLS was successfully cultured in vitro and simultaneously verified to exist in the fat body of BPH by sequence analysis and nested polymerase chain reaction (PCR).The cultured YLS isolate in vitro was identified as a member of the genus Candida on the basis of 18S rDNA (ribosomal DNA) and 5.8S-ITS (internal transcribed spacer) rDNA sequence and a phylogenetic analysis of ITS sequences from yeast.Therefore,this yeast isolate was named as Candida-like symbiotes.Candida-like symbiotes was found to exist in fat bodies,ovaries and newly laid eggs of the BPH,but not in the heads,thoraxes and mid-guts.In addition,the number of Candida-like symbiotes in 1 x 106 of purified YLS from BPH fat bodies was speculated to be (5.32 ± 0.22) × 104 on the basis of a quantitative PCR analysis.

  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. Genome-wide analysis of Dongxiang wild rice (Oryza rufipogon Griff.) to investigate lost/acquired genes during rice domestication

    OpenAIRE

    Zhang, Fantao; Xu, Tao; Mao, Linyong; Yan, Shuangyong; Chen, Xiwen; Wu, Zhenfeng; Chen, Rui; Luo, Xiangdong; Xie, Jiankun; Gao, Shan

    2016-01-01

    Background It is widely accepted that cultivated rice (Oryza sativa L.) was domesticated from common wild rice (Oryza rufipogon Griff.). Compared to other studies which concentrate on rice origin, this study is to genetically elucidate the substantially phenotypic and physiological changes from wild rice to cultivated rice at the whole genome level. Results Instead of comparing two assembled genomes, this study directly compared the Dongxiang wild rice (DXWR) Illumina sequencing reads with th...

  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. Mapping rice areas of South Asia using MODIS multitemporal data

    Science.gov (United States)

    Gumma, M.K.; Nelson, A.; Thenkabail, P.S.; Singh, A.N.

    2011-01-01

    Our goal is to map the rice areas of six South Asian countries using moderate-resolution imaging spectroradiometer (MODIS) time-series data for the time period 2000 to 2001. South Asia accounts for almost 40% of the world's harvested rice area and is also home to 74% of the population that lives on less than $2.00 a day. The population of the region is growing faster than its ability to produce rice. Thus, accurate and timely assessment of where and how rice is cultivated is important to craft food security and poverty alleviation strategies. We used a time series of eight-day, 500-m spatial resolution composite images from the MODIS sensor to produce rice maps and rice characteristics (e.g., intensity of cropping, cropping calendar) taking data for the years 2000 to 2001 and by adopting a suite of methods that include spectral matching techniques, decision trees, and ideal temporal profile data banks to rapidly identify and classify rice areas over large spatial extents. These methods are used in conjunction with ancillary spatial data sets (e.g., elevation, precipitation), national statistics, and maps, and a large volume of field-plot data. The resulting rice maps and statistics are compared against a subset of independent field-plot points and the best available subnational statistics on rice areas for the main crop growing season (kharif season). A fuzzy classification accuracy assessment for the 2000 to 2001 rice-map product, based on field-plot data, demonstrated accuracies from 67% to 100% for individual rice classes, with an overall accuracy of 80% for all classes. Most of the mixing was within rice classes. The derived physical rice area was highly correlated with the subnational statistics with R2 values of 97% at the district level and 99% at the state level for 2000 to 2001. These results suggest that the methods, approaches, algorithms, and data sets we used are ideal for rapid, accurate, and large-scale mapping of paddy rice as well as for generating

  14. Diversity of the Ty-1 copia retrotransposon Tos17 in rice (Oryza sativa L.) and the AA genome of the Oryza genus

    OpenAIRE

    Petit, J.; Bourgeois, E; Stenger, W.; Bes, M.; Droc, G.; Meynard, D.; Courtois, B.; Ghesquière, Alain; Sabot, François; Panaud, O.; Guiderdoni, E.

    2009-01-01

    Retrotransposons are mobile genetic elements, ubiquitous in Eukaryotic genomes, which have proven to be major genetic tools in determining phylogeny and structuring genetic diversity, notably in plants. We investigate here the diversity of the Ty1-copia retrotransposon Tos17 in the cultivated rice of Asian origin (Oryza sativa L.) and related AA genome species of the Oryza genus, to contribute understanding of the complex evolutionary history in this group of species through that of the eleme...

  15. Comparative Analysis of Genomes in Oryza sativa, O.officinalis, and O. meyeriana with C0t-1 DNA and Genomic DNA of Cultivated Rice

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of C0t-1 DNA and genomic DNA from the cultivated rice. The coverage percentage (%) and size (Mb) of C0t-1 DNA in O. sativa, O. officinalis, and O. meyeriana were 47.1 ±0.16, 38.61 ±0.13, 44.38±0.13, and 212.33± 1.21,269.42 ± 0.89, 532.56± 1.68 Mb, respectively. The coverage percentage and size of genomic DNA from O. sativa in O. officinalis and O. meyeriana were 91.0, 93.6% and 634, 1 123 Mb, respectively, in which 365 and 591 Mb in O. officinalis and O. meyeriana were from O. sativa genomic DNA, but not from repetitive sequences of O. sativa, and the uncoverage genome size in O. officinalis and O. meyeriana were 64 and 78 Mb, respectively. In addition, karyotype analysis was conducted based on the signal bands of C0t-1 DNA in O. sativa, O. officinalis, and O. meyeriana. The results showed that highly and moderately repetitive sequences in Oryza genus were conserved as the functional genes during evolution. The repetitive sequences reduplication may be one of the important causes of the genome enlargement of O. officinalis and O. meyeriana, and O. officinalis genome enlarged more slowly when compared with O. meyeriana. Based on the above results, it is concluded that O. officinalis and O. meyeriana were formed by reduplication, rearrangement, and gene selective loss during the evolution process.

  16. 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.

  17. 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

  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. 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

  20. The estimation of rice paddy yield with GRAMI crop model and Geostationary Ocean Color Imager (GOCI) image over South Korea

    Science.gov (United States)

    Yeom, J. M.; Kim, H. O.

    2014-12-01

    In this study, we estimated the rice paddy yield with moderate geostationary satellite based vegetation products and GRAMI model over South Korea. Rice is the most popular staple food for Asian people. In addition, the effects of climate change are getting stronger especially in Asian region, where the most of rice are cultivated. Therefore, accurate and timely prediction of rice yield is one of the most important to accomplish food security and to prepare natural disasters such as crop defoliation, drought, and pest infestation. In the present study, GOCI, which is world first Geostationary Ocean Color Image, was used for estimating temporal vegetation indices of the rice paddy by adopting atmospheric correction BRDF modeling. For the atmospheric correction with LUT method based on Second Simulation of the Satellite Signal in the Solar Spectrum (6S), MODIS atmospheric products such as MOD04, MOD05, MOD07 from NASA's Earth Observing System Data and Information System (EOSDIS) were used. In order to correct the surface anisotropy effect, Ross-Thick Li-Sparse Reciprocal (RTLSR) BRDF model was performed at daily basis with 16day composite period. The estimated multi-temporal vegetation images was used for crop classification by using high resolution satellite images such as Rapideye, KOMPSAT-2 and KOMPSAT-3 to extract the proportional rice paddy area in corresponding a pixel of GOCI. In the case of GRAMI crop model, initial conditions are determined by performing every 2 weeks field works at Chonnam National University, Gwangju, Korea. The corrected GOCI vegetation products were incorporated with GRAMI model to predict rice yield estimation. The predicted rice yield was compared with field measurement of rice yield.

  1. 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

  2. Detection of Inorganic Arsenic in Rice Using a Field Test Kit: A Screening Method.

    Science.gov (United States)

    Bralatei, Edi; Lacan, Severine; Krupp, Eva M; Feldmann, Jörg

    2015-11-17

    Rice is a staple food eaten by more than 50% of the world's population and is a daily dietary constituent in most South East Asian countries where 70% of the rice export comes from and where there is a high level of arsenic contamination in groundwater used for irrigation. Research shows that rice can take up and store inorganic arsenic during cultivation, and rice is considered to be one of the major routes of exposure to inorganic arsenic, a class I carcinogen for humans. Here, we report the use of a screening method based on the Gutzeit methodology to detect inorganic arsenic (iAs) in rice within 1 h. After optimization, 30 rice commodities from the United Kingdom market were tested with the field method and were compared to the reference method (high-performance liquid chromatography-inductively coupled plasma-mass spectrometry, HPLC-ICP-MS). In all but three rice samples, iAs compound can be determined. The results show no bias for iAs using the field method. Results obtained show quantification limits of about 50 μg kg(-1), a good reproducibility for a field method of ±12%, and only a few false positives and negatives (<10%) could only be recorded at the 2015 European Commission (EC) guideline for baby rice of 100 μg kg(-1), while none were recorded at the maximum level suggested by the World Health Organization (WHO) and implemented by the EC for polished and white rice of 200 μg kg(-1). The method is reliable, fast, and inexpensive; hence, it is suggested to be used as a screening method in the field for preselection of rice which violates legislative guidelines.

  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. 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.

  5. 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”.

  6. 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.

  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. Tracing ancestor rice of Suriname Maroons back to its African origin.

    Science.gov (United States)

    van Andel, Tinde R; Meyer, Rachel S; Aflitos, Saulo A; Carney, Judith A; Veltman, Margaretha A; Copetti, Dario; Flowers, Jonathan M; Havinga, Reinout M; Maat, Harro; Purugganan, Michael D; Wing, Rod A; Schranz, M Eric

    2016-10-03

    African rice (Oryza glaberrima) and African cultivation practices are said to have influenced emerging colonial plantation economies in the Americas(1,2). However, the level of impact of African rice practices is difficult to establish because of limited written or botanical records(2,3). Recent findings of O. glaberrima in rice fields of Suriname Maroons bear evidence of the high level of knowledge about rice among African slaves and their descendants, who consecrate it in ancestor rituals(4,5). Here we establish the strong similarity, and hence likely origin, of the first extant New World landrace of O. glaberrima to landraces from the Upper Guinean forests in West Africa. We collected African rice from a Maroon market in Paramaribo, Suriname, propagated it, sequenced its genome(6) and compared it with genomes of 109 accessions representing O. glaberrima diversity across West Africa. By analysing 1,649,769 single nucleotide polymorphisms (SNPs) in clustering analyses, the Suriname sample appears sister to an Ivory Coast landrace, and shows no evidence of introgression from Asian rice. Whereas the Dutch took most slaves from Ghana, Benin and Central Africa(7), the diaries of slave ship captains record the purchase of food for provisions when sailing along the West African Coast(8), offering one possible explanation for the patterns of genetic similarity. This study demonstrates the utility of genomics in understanding the largely unwritten histories of crop cultures of diaspora communities.

  9. 粳稻新品种垦育38的特征特性与栽培技术%Characteristics and Cultivation Techniques of New Japonic Rice Variety Kenyu 38

    Institute of Scientific and Technical Information of China (English)

    王永新; 张启星; 吴新海

    2012-01-01

    The new japonic rice variety Kenyu 38 had the characteristics of 101.5 cm of plant height,tough stalk,high lodging resistance,resistance to rice stripe disease,74.70% of milled rice rate,and 9.10% of protein content.The average yield was 9 158.0 kg/hm2 in the regional tests from 2007 to 2008 in Hebei,which increased by 6.96% than the control Kenyu 20,and the difference reached a very significant level.It grew about 158 days in the east of Hebei,which was suitable for planting in Tangshan and Qinhuangdao with single cropping rice cultivation method.%粳稻新品种垦育38株高101.5 cm,茎秆坚韧,高抗倒伏,抗水稻条纹叶枯病,精米率为74.70%,蛋白质含量为9.10%。河北省水稻区域试验2 a平均产量为9158.0 kg/hm2,较对照垦育20号增产6.96%,达极显著水平。该品种在冀东稻区生育期158 d左右,适于在河北省长城以南唐山、秦皇岛稻区作一季稻多种栽培方式种植。

  10. Geochemical Modeling of Zinc Bioavailability for Rice

    NARCIS (Netherlands)

    Gao, X.; Schröder, T.J.; Hoffland, E.; Zou, C.; Zhang, F.; Zee, van der S.E.A.T.M.

    2010-01-01

    The transition from anaerobic to aerobic rice (Oryza sativa L.) cultivation has been reported to decrease Zn bioavailability. To determine and understand the differences in plant Zn uptake between anaerobic and aerobic rice cultivation systems, a field plot experiment was conducted with direct-seede

  11. 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.

  12. 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.

  13. 稻草、茭白鞘叶栽培凤尾菇试验研究%Pleurotus sajor-caju experiments cultivation of rice straw and sheathing leaf of zizania latifolia

    Institute of Scientific and Technical Information of China (English)

    阎锡海; 罗四英

    2014-01-01

    传统的凤尾菇栽培料主要成分是木屑,试验采用稻草、茭白鞘叶代替部分木屑栽培凤尾菇,用不同的栽培料配方栽培凤尾菇,共设置7个试验组,以传统培养料配方为对照组( CK)。通过对菌丝生长、子实体生长和产量等指标的考察,分析不同配方对凤尾菇生长的影响。结果表明:试验组中配料以木屑、稻草、茭白鞘叶以合适比例混合为基料时,凤尾菇产量最好,生物学效率最高为32.24%。%Pleurotus sajor-caju is nutritious and delicious .Its is a kind of mushroom welcomed by peo-ple.In this experiment , rice straw and zizania sheathing leaf are used to take place of sawdust to cultivate the Pleurotus sajor-caju.We set 7 experiment groups using different cultivating materials .and set traditional culti-vating experiment as control group ( CK) .We analyzed the influence of different cultivating material by record-ing the growing of mycelium and sporocarp .The result shows:group G properly mixed materials of sawdust , pleurotus sajor-caju and sheathing leaves of zizania latifolia is best suitable for growing sporocarp ,with biotrans-formation efficiency of group H being 32 .24%.

  14. Elucidation of molecular dynamics of invasive species of rice

    Science.gov (United States)

    Cultivated rice fields are aggressively invaded by weedy rice in the U.S. and worldwide. Weedy rice results in loss of yield and seed contamination. The molecular dynamics of the evolutionary adaptive traits of weedy rice are not fully understood. To understand the molecular basis and identify the i...

  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. A Technology for Screening Safe Cultivated Rice Areas from Farmland Affected by Cadmium%土壤镉积累农田水稻安全种植区判别技术研究

    Institute of Scientific and Technical Information of China (English)

    赵玉杰; 刘潇威; 唐世荣; 李野; 师荣光; 高尚宾

    2011-01-01

    Farmland contamination with heavy metals such as cadmium (Cd) poses a potential hazard for rice safety production. To discriminate rice safe cultivated areas from farmland affected with cadmium is a foundation for insuring rice safety production. In this paper, A case of adopting ordinary indicator kriging to distinguish rice safe cultivated zone from the affected district with abundant sulfur coals was studied. The study area is located in Lu county, southeastern Sichuan province. The statistical results showed that 34. 98% of the soil samples in cadmium (Cd) concentration exceeded the threshold (0. 3mg/kg)of the second class set by the National Soil Environmental Quality Standard ( GB 15618-1995). Other heavy metal concentrations were comparatively lower than the standard values. Omnidirection and anisotropic experimental semivariograms of the indictor functions were calculated and cross-validation methods were adopted to choose the semivariograms models and parameters. The cross-validation results showed that the omnidirection spherical semivariogram with nugget was better than the anisotropic spherical semivariogram in reflecting the spatial variability of the indicator functions. Ordinary indicator kriging was used to calculate the spatial and probability distribution of the soil Cd exceeding the safety threshold (0. 3mg/kg). The estimation results showed that the rice safety cultivated area could not be distinguished by the estimated E-type Cd spatial distribution. But the exceeding probability with 0.45 as the determine threshold could achieve better results and the error rate of training set and validation set was 1.9% ,21.7% .respectively.%农田重金属镉(Cd)污染已成为水稻安全生产的重大隐患,如何判别受Cd危害的水稻种植区的安全区是保障这些区域稻米安全生产的基础.本文以富煤矿区四川省东南部泸县为例研究了普通指示克里格法在判别稻米安全生产区中的应用.统计结果表

  17. 杂交稻元丰优86在永定种植表现及高产栽培技术%Planting Performance and High-yielding Cultivation Techniques of Hybrid Rice Combination Yuanfengyou 86 in Yongding Country

    Institute of Scientific and Technical Information of China (English)

    游梅兰

    2014-01-01

    Yuanfengyou 86, derived from the CMS line Yuanfeng A and a restorer line Minghui 86, was a new hybrid rice combination. Yuanfengyou 86 was registered and released for commercial production by National Crop Variety Appraisal Committee in Fujian province in 2011. During the year of 2012-1013, Yuanfengyou 86 was introduced and planted in Yongding county of Fujian province. In this paper, we introduced planting performance and high-yielding cultivation techniques of Yuanfengyou 86.%元丰优86是用元丰A×明恢86配组育成的三系杂交稻新品种,2011年通过福建省品种审定。2012—2013年在永定县仙师乡示范种植,掌握其特征特性和高产栽培技术。

  18. 两系杂交稻株两优22特征特性与栽培技术%Characteristics and Cultivation Techniques of Two-line Hybrid Rice Zhuliangyou 22

    Institute of Scientific and Technical Information of China (English)

    夏品蒲

    2015-01-01

    Zhuliangyou 22 is a two-line indica hybrid rice variety and released by the nation in 2012. It was planted as double cropping early rice at Fuding city, exhibiting the characteristics of moderate growth duration, high yield, suitable plant type, tolerant fertilizer, resistant lodging, and strong resistant disease. The cultivation techniques at Fuding city mainly included: timely sowing and fostering robust seedling, rational transplanting density with sufficient basic seedling, applying sufficient base fertilizer and formula fertilization, scientific water management, and comprehensive control of pests and diseases.%株两优22是籼型两系杂交水稻品种,2012年通过国家品种审定。在福鼎市作双季早稻种植,表现生育期适中、丰产性好、耐肥抗倒、抗病性较强等特点。总结了其在福鼎作双季早稻种植表现及高产栽培技术。

  19. 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

  20. 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.

  1. Cultivable Methylobacterium species diversity in rice seeds identified with whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis.

    Science.gov (United States)

    Okumura, Marie; Fujitani, Yoshiko; Maekawa, Masahiko; Charoenpanich, Jittima; Murage, Hunja; Kimbara, Kazuhide; Sahin, Nurettin; Tani, Akio

    2017-02-01

    Methylobacterium species are methylotrophic bacteria that widely inhabit plant surfaces. In addition to studies on methylotrophs as model organisms, research has also been conducted on their mechanism of plant growth promotion as well as the species-species specificity of plant-microbe interaction. We employed whole-cell matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (WC-MS) analysis, which enables the rapid and accurate identification of bacteria at the species level, to identify Methylobacterium isolates collected from the rice seeds of different cultivars harvested in Japan, Thailand, and Kenya. Rice seeds obtained from diverse geographical locations showed different communities of Methylobacterium species. We found that M. fujisawaense, M. aquaticum, M. platani, and M. radiotolerans are the most frequently isolated species, but none were isolated as common species from 18 seed samples due to the highly biased communities in some samples. These findings will contribute to the development of formulations containing selected species that promote rice growth, though it may be necessary to customize the formulations depending on the cultivars and farm conditions.

  2. 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.

  3. 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.

  4. Metabolite profiling of the short-term responses of rice leaves (Oryza sativa cv. Ilmi) cultivated under different LED lights and its correlations with antioxidant activities.

    Science.gov (United States)

    Jung, Eun Sung; Lee, Sarah; Lim, Sun-Hyung; Ha, Sun-Hwa; Liu, Kwang-Hyeon; Lee, Choong Hwan

    2013-09-01

    Metabolite profiling of rice leaves (Oryza sativa cv. Ilmi) was performed to investigate the short-term responses to different light-emitting diode (LED) lights, blue (B), green (G), red (R), white (W), shade (S), by using gas chromatography-ion trap-mass spectrometry (GC-IT-MS) and ultra-performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-Q-TOF-MS) with multivariate analysis. Clear grouping patterns of each light-grown sample, except G and W, were shown in partial least squares-discriminant analysis (PLS-DA). Thirty-two primary metabolites and eleven secondary metabolites were selected and visualized using heatmap. Antioxidant activities of rice leaves followed the order B=W=G>R>S and isoorientin-2''-O-glucoside, isovitexin-2''-O-glucoside, isoorientin-2''-O-(6'''-ρ-coumaroyl)-glucoside, and isoscoparin-2''-O-glucoside showed similar relative differences and had higher Pearson's correlation coefficients than other metabolites in correlation network. According to the orthogonal projection to latent structures-discriminant analysis (OPLS-DA) between B and R, the levels of amino acids, organic acids, fatty acids, and flavonoid glycosides were relatively high in B, whereas the glucose and fructose levels were high in R.

  5. Gas exchange variability and water use efficiency of thirty landraces of rice still under cultivation in Kumaun region of the Indian Central Himalaya.

    Science.gov (United States)

    Agnihotri, R K; Palni, L M S; Chandra, Suman; Joshi, S C

    2009-10-01

    Gas exchange characteristics of thirty landraces of rice (Oryza sativa L.) along with an introduced variety VL-206 (recommended high yielding variety for rainfed uplands of the Indian Central Himalaya, ICH), grown in earthen pots and kept in the open at the Institute nursery at Kosi (1150m amsl, 79°38'10″E and 29°38'15″N) were studied. The photosynthetic rate (Pn) and other related parameters were found to vary considerably among landraces. Based on the comparison of Pn of landraces with that of VL-206, these were categorized into two groups: i) high (〉6.0 µmol m(-2)s(-1)), and ii) low (stomatal conductance (gs), transpiration rate (E), water use efficiency (WUE), mesophyll efficiency (low Ci/gs ratio) and chlorophyll (Chl) content in comparison to landraces in the low Pn group. However, significant differences were not found in the intercellular CO2 concentration (Ci) between landraces belonging to the high and low Pn groups. Differences among landraces were found with regard to dark respiration; landraces with low Pn respired proportionately more of the carbon fixed than those of high Pn group. Based on the studied gas exchange characteristics Saurajubawan, Syaudhan and Taichin, local landraces of rice, may be identified as potential cultivars with high Pn and WUE.

  6. 杂草稻和栽培稻叶片下表皮结构特征的观察及聚类分析%Cluster Analysis of Weedy Rice and Cultivated Rice Based on the Structural Characteristics of Leaf Lower Epidermis

    Institute of Scientific and Technical Information of China (English)

    杨琳; 戴伟民; 强胜; 宋小玲

    2009-01-01

    利用光学显微镜对33份杂草稻及6份栽培稻材料的叶片下表皮中央长细胞及其各级乳突、气孔器及其乳突的结构特征进行了观察、统计后作主成分分析及聚类分析.主成分分析后得到3个在各个性状因子中贡献率最大的主成分,分别是中央长细胞大乳突、中乳突及小乳突的数目、大小,气孔密度.叶表皮结构特征在各供试材料之间有一定的变异和特异性,在杂草稻分类鉴定及亲缘关系的研究中具有一定的价值.%The characteristics of long cells, papillae with different sizes, stomata on leaf-back in 33 accessions of weedy rice (Oryza sativa f. spontanea) and 6 accessions of cultivated rice (Oryza sativa L.) were observed with a light microscopy (LM). The principal component analysis (PCA) and cluster analysis were conducted using the above data. Three principal components were obtained, in which the number and diameter of the large, medium and small papillae on the long cells, stomatal density contributed most variance. The morphological features of the leaf epidermis varied significantly among the accessions. The results may be valuable for the taxonomic identification and studies on origins of weedy rice.

  7. 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。

  8. Irrigation Difference and Productivity Variations in Paddy Cultivation: Field Evidences from Udalguri District of Assam

    OpenAIRE

    Phanindra GOYARI

    2014-01-01

    Using field survey data, the paper examines the seasonal variation of irrigation facilities for cultivation of paddy with special emphasis on summer paddy in Assam. Paddy is cultivated in three seasons: autumn, winter and summer. In terms of acreage and production, winter rice has traditionally been the most dominant. However, the acreage shares of winter and autumn rice in total rice area have been declining continuously over the years. On the contrary, the importance of summer rice has been...

  9. Asian Heroes

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    China,South Korea and Japan keep Olympic flag flying Atotal of 19 countries and regions of Asia competed at the 2008 Beijing Olympics, winning 86 gold, 54 silver and 72 bronze medals. Their gold medal haul accounted for 28.5 percent of the total 302 gold medals awarded. Of the Asian medal winners, China, Japan and South Korea were the top three accounting for 73 gold medals, and 84.9 percent of all medals won by Asian countries.

  10. Planting Performance and High-yielding Cultivation Techniques for Hybrid Rice Combination Shenliangyou 862 at Yong,an City%深两优862在永安市种植表现与高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    林增贵

    2016-01-01

    深两优862是由江苏明天种业科技有限公司、南昌穗民农业科技有限公司、临湘市兆农科技研发中心,用深08S与R5662配组育成的杂交水稻新品种。具有长势旺,分蘖力强,成穗率高,有效穗多,高产稳产,米质优等特点。介绍深两优862在永安市种植表现与高产栽培技术。%A new hybrid rice combination Shenliangyou 862 derived from the cross of a sterile line Shen 08S and a restorer line R5662 was developed by Jiangsu Mingtian Seed Science and Technology Co., Ltd, Nan-chang Suimin Agricultural Science and Technology Co., Ltd and Linxiang Zhaonong Science and Technology Research and Development Center. It showed the characteristics of vigorous growth, strong tillering ability, high earbearing tiller percentage, more effective panicle number, high and stable yield, and good quality. Planting performance and high-yielding cultivation techniques for Shenliangyou 862 at Yong,an city was in-troduced in this paper.

  11. 秸秆全量还田下连作晚稻不同栽培方式比较研究%Comparative Study on Different Cultivation Patterns of Later Rice in Straw Returning

    Institute of Scientific and Technical Information of China (English)

    闫川; 范天云; 郑学强; 阮关海; 陈珊宇; 徐彬彬; 洪晓富

    2011-01-01

    The application of early straw returning and later rice simplified cultivation techniques are the most important measure both in the current development of new farming systems and quality and efficient agriculture. In this study, the three cultivation patterns (handmade transplanting, mechanical interpolation and scattered transplanted) of later rice were comparative studied. The results showed that the method of handmade transplanting got the highest yield, but only a little bit higher than the mechanical interpolation, while scattered transplanted got much lower yield. Compared to handmade transplanting treatment, the dry matter accumulation of mechanical interpolation was similar in heading stage, maturity stage and heading-maturity stage; and the dry matter accumulation of handmade transplanting and mechanical interpolation was significantly higher than the scattered transplanted in heading-maturity stage. The effective tillers of three cultivation patterns were reduced in straw returning, especially scattered transplanted. In addition, compared with the handmade transplanting and scattered transplanted, the mechanical interpolation significantly saved more time and money. On the whole, in early straw returning conditions, mechanical interpolation expresses high and stable yield. Therefore, the mechanical interpolation is worthy of planting in Zhejiang Province, and it has broad application prospects.%应用早稻秸秆全量还田和连作晚稻轻简化栽培技术是当前发展新型农作制度和质量效益型农业的重要措施.此研究对早稻秸秆全量还田条件下连作晚稻手移栽、机插和抛秧3种栽培方式进行比较,结果表明,连作晚稻手移栽栽培方式产量最高,机插次之,抛秧的产量最低.但手移栽栽培方式的产量与机插处理的差异不显著,但二者均与抛秧栽培方式的差异达到显著水平.与手移栽处理相比,机插处理抽穗期、成熟期、抽穗至成熟期的干物质含

  12. BIBLE A whole-air sampling as a window on Asian biogeochemistry

    Science.gov (United States)

    Elliott, Scott; Blake, Donald R.; Blake, Nicola J.; Dubey, Manvendra K.; Rowland, F. Sherwood; Sive, Barkley C.; Smith, Felisa A.

    2003-02-01

    Asian trace gas and aerosol emissions into carbon, nitrogen, and other elemental cycles will figure prominently in near term Earth system evolution. Atmospheric hydrocarbon measurements resolve numerous chemical species and can be used to investigate sourcing for key geocarriers. A recent aircraft study of biomass burning and lightning (BIBLE A) explored the East Asian atmosphere and was unique in centering on the Indonesian archipelago. Samples of volatile organics taken over/between the islands of Japan, Saipan, Java, and Borneo are here examined as a guide to whole-air-based studies of future Asian biogeochemistry. The midlatitude onshore/offshore pulse and tropical convection strongly influence concentration distributions. As species of increasing molecular weight are considered, rural, combustion, and industrial source regimes emerge. Methane-rich inputs such as waste treatment and rice cultivation are evidenced in the geostrophic outflow. The Indonesian atmosphere is rich in biomass burning markers and also those of vehicular activity. Complexity of air chemistry in the archipelago is a direct reflection of diverse topography, land use, and local economies in a rapidly developing nation. Conspicuous in its absence is the fingerprint for liquefied petroleum gas leakage, but it can be expected to appear as demand for clean fossil fuels rises along with per capita incomes. Combustion tracers indicate high nitrogen mobilization rates, linking regional terrestrial geocycles with open marine ecosystems. Sea to air fluxes are superimposed on continental and marine backgrounds for the methyl halides. However, ocean hot spots are not coordinated and suggest an intricate subsurface kinetics. Levels of long-lived anthropogenic halocarbons attest to the success of international environmental treaties while reactive chlorine containing species track industrial air masses. The dozens of hydrocarbons resolvable by gas chromatographic methods will enable monitoring of

  13. 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

  14. Effects of different mulching materials on rice yield in transplanting field with semiarid cultivation method%半干旱栽培稻田不同秸秆覆盖材料的产量效应

    Institute of Scientific and Technical Information of China (English)

    陶诗顺; 王学春; 徐健蓉

    2012-01-01

    panicles by 4% -8% , weight of 1000 grains by0.6% - 1.7% under straw mulching treatments, compared with that under no mulching treatment. (2) Integrated with semiarid cultivation method, straw mulching method could significantly increase rice yield in transplanting field in the northwest region of Sichuan Province. The average yield of Cangyou 725 and Dyou 363 under mulching treatments with rapeseed husk, winter wheat husk and winter wheat straw increased by 10.2% , 7.0% and 7. 7% respectively, compared with that under no mulching treatment.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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, p<0.001). However, rice percent methylmercury (of total mercury) did not differ statistically between polluted and non-polluted sites (Wilcoxon rank sum, p=0.35), suggesting comparable mercury methylation rates in paddy soil across these sites and/or similar accumulation of mercury species for these rice cultivars. Studies characterizing the effects of rice cultivation under more aerobic conditions were reviewed to determine the mitigation potential of this practice. Rice management practices utilizing alternating wetting and drying (instead of continuous flooding) caused soil methylmercury levels to spike, resulting in a strong methylmercury pulse after fields were dried and reflooded; however, it is uncertain whether this led to increased translocation of methylmercury from paddy soil to rice grain. Due to the potential health risks, it is advisable to investigate this issue further, and to develop separate water management strategies for mercury polluted and non-polluted sites, in order to minimize methylmercury exposure through rice ingestion.

  1. Genomic dissection of small RNAs in wild rice (Oryza rufipogon): lessons for rice domestication.

    Science.gov (United States)

    Wang, Yu; Bai, Xuefei; Yan, Chenghai; Gui, Yiejie; Wei, Xinghua; Zhu, Qian-Hao; Guo, Longbiao; Fan, Longjiang

    2012-11-01

    The lack of a MIRNA set and genome sequence of wild rice (Oryza rufipogon) has prevented us from determining the role of MIRNA genes in rice domestication. In this study, a genome, three small RNA populations and a degradome of O. rufipogon were sequenced by Illumina platform and the expression levels of microRNAs (miRNAs) were investigated by miRNA chips. A de novo O. rufipogon genome was assembled using c. 55× coverage of raw sequencing data and a total of 387 MIRNAs were identified in the O. rufipogon genome based on c. 5.2 million unique small RNA reads from three different tissues of O. rufipogon. Of these, O. rufipogon MIRNAs, 259 were not found in the cultivated rice, suggesting a loss of these MIRNAs in the cultivated rice. We also found that 48 MIRNAs were novel in the cultivated rice, suggesting that they were potential targets of domestication selection. Some miRNAs showed significant expression differences between wild and cultivated rice, suggesting that expression of miRNA could also be a target of domestication, as demonstrated for the miR164 family. Our results illustrated that MIRNA genes, like protein-coding genes, might have been significantly shaped during rice domestication and could be one of the driving forces that contributed to rice domestication.

  2. Production of rice straw hydrolysis enzymes by the fungi Trichoderma reesei and Humicola insolens using rice straw as a carbon source.

    Science.gov (United States)

    Kogo, Takashi; Yoshida, Yuki; Koganei, Keisuke; Matsumoto, Hitoshi; Watanabe, Taisuke; Ogihara, Jun; Kasumi, Takafumi

    2017-02-11

    Rice straw was evaluated as a carbon source for the fungi, Trichoderma reesei and Humicola insolens, to produce enzymes for rice straw hydrolysis. The enzyme activity of T. reesei and H. insolens cultivated in medium containing non-treated rice straw were almost equivalent to the enzyme of T. reesei cultivated in Avicel medium, a form of refined cellulose. The enzyme activity of T. reesei cultivated in medium containing NH4OH-treated rice straw was 4-fold higher than enzyme from cultures grown in Avicel medium. In contrast, H. insolens enzyme from cultures grown in NH4OH-treated rice straw had significantly lower activity compared with non-treated rice straw or Avicel. The combined use of T. reesei and H. insolens enzymes resulted in a significant synergistic enhancement in enzymatic activity. Our data suggest that rice straw is a promising low-cost carbon source for fungal enzyme production for rice straw hydrolysis.

  3. Estimating Rice Yield under Changing Weather Conditions in Kenya Using CERES Rice Model

    OpenAIRE

    W. O. Nyang’au; Mati, B. M.; Kalamwa, K.; Wanjogu, R. K.; L. K. Kiplagat

    2014-01-01

    Effects of change in weather conditions on the yields of Basmati 370 and IR 2793-80-1 cultivated under System of Rice Intensification (SRI) in Mwea and Western Kenya irrigation schemes were assessed through sensitivity analysis using the Ceres rice model v 4.5 of the DSSAT modeling system. Genetic coefficients were determined using 2010 experimental data. The model was validated using rice growth and development data during the 2011 cropping season. Two SRI farmers were selected randomly from...

  4. Studies on the Ecological Adaptability of Growing Rice with Floating Bed on the Dilute Biogas Slurry

    Directory of Open Access Journals (Sweden)

    Qun Kang

    2016-01-01

    Full Text Available This study aimed to explore the ecological adaptability and the possibility of growing rice with floating bed on the dilute biogas slurry. The results of the experiments show that the growth stage, rice plant height, and rice yield and quality were significantly affected by multiple dilutions; rice plants cultivated with 45 multiple dilutions had better ecological adaptability than others. In the 45 multiple dilutions’ group, the yield of rice was 13.3 g/bucket (8 rice plants, milled rice rate was 63.1%, and the content of crude protein in the rice was 6.3%. The concentrations of heavy metals in the rice cultivated with 30 multiple dilutions’ slurry, such as total lead, cadmium, mercury, chromium, and arsenic, were all below the national standard. The study shows that it is possible and safe to cultivate rice plants with no soil but diluted biogas slurry. In the experiments, the yield, milled rice rate, and crude protein of the rice cultivated with slurry were not as much as those of rice cultivated with regular way in soil. This study provides the basic theoretical support for the development of biogas projects and the potential achievement of organic farming in special agricultural facilities and circular economy.

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

    NARCIS (Netherlands)

    Kraker, de J.

    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 bi

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. High occurrence of functional new chimeric genes in survey of rice chromosome 3 short arm genome sequences.

    Science.gov (United States)

    Zhang, Chengjun; Wang, Jun; Marowsky, Nicholas C; Long, Manyuan; Wing, Rod A; Fan, Chuanzhu

    2013-01-01

    In an effort to identify newly evolved genes in rice, we searched the genomes of Asian-cultivated rice Oryza sativa ssp. japonica and its wild progenitors, looking for lineage-specific genes. Using genome pairwise comparison of approximately 20-Mb DNA sequences from the chromosome 3 short arm (Chr3s) in six rice species, O. sativa, O. nivara, O. rufipogon, O. glaberrima, O. barthii, and O. punctata, combined with synonymous substitution rate tests and other evidence, we were able to identify potential recently duplicated genes, which evolved within the last 1 Myr. We identified 28 functional O. sativa genes, which likely originated after O. sativa diverged from O. glaberrima. These genes account for around 1% (28/3,176) of all annotated genes on O. sativa's Chr3s. Among the 28 new genes, two recently duplicated segments contained eight genes. Fourteen of the 28 new genes consist of chimeric gene structure derived from one or multiple parental genes and flanking targeting sequences. Although the majority of these 28 new genes were formed by single or segmental DNA-based gene duplication and recombination, we found two genes that were likely originated partially through exon shuffling. Sequence divergence tests between new genes and their putative progenitors indicated that new genes were most likely evolving under natural selection. We showed all 28 new genes appeared to be functional, as suggested by Ka/Ks analysis and the presence of RNA-seq, cDNA, expressed sequence tag, massively parallel signature sequencing, and/or small RNA data. The high rate of new gene origination and of chimeric gene formation in rice may demonstrate rice's broad diversification, domestication, its environmental adaptation, and the role of new genes in rice speciation.

  13. 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.

  14. 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

  15. A triallelic system of S5 is a major regulator of the reproductive barrier and compatibility of indica-japonica hybrids in rice.

    Science.gov (United States)

    Chen, Jiongjiong; Ding, Jihua; Ouyang, Yidan; Du, Hongyi; Yang, Jiangyi; Cheng, Ke; Zhao, Jie; Qiu, Shuqing; Zhang, Xuelian; Yao, Jialing; Liu, Kede; Wang, Lei; Xu, Caiguo; Li, Xianghua; Xue, Yongbiao; Xia, Mian; Ji, Qing; Lu, Jufei; Xu, Mingliang; Zhang, Qifa

    2008-08-12

    Hybrid sterility is a major form of postzygotic reproductive isolation. Although reproductive isolation has been a key issue in evolutionary biology for many decades in a wide range of organisms, only very recently a few genes for reproductive isolation were identified. The Asian cultivated rice (Oryza sativa L.) is divided into two subspecies, indica and japonica. Hybrids between indica and japonica varieties are usually highly sterile. A special group of rice germplasm, referred to as wide-compatibility varieties, is able to produce highly fertile hybrids when crossed to both indica and japonica. In this study, we cloned S5, a major locus for indica-japonica hybrid sterility and wide compatibility, using a map-based cloning approach. We show that S5 encodes an aspartic protease conditioning embryo-sac fertility. The indica (S5-i) and japonica (S5-j) alleles differ by two nucleotides. The wide compatibility gene (S5-n) has a large deletion in the N terminus of the predicted S5 protein, causing subcellular mislocalization of the protein, and thus is presumably nonfunctional. This triallelic system has a profound implication in the evolution and artificial breeding of cultivated rice. Genetic differentiation between indica and japonica would have been enforced because of the reproductive barrier caused by S5-i and S5-j, and species coherence would have been maintained by gene flow enabled by the wide compatibility gene.

  16. 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.

  17. 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.

  18. 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.

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

    Science.gov (United States)

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

    2011-01-01

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

  20. 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.

  1. 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.

  2. Effect of Different Sowing Dates in South Henan ’s Rice-growing Areas on the Growth and Yield of Ratoon Rice

    Institute of Scientific and Technical Information of China (English)

    Xiangchen LIU; Daqing FENG; Guilong YU; Haiying ZHAO; Li QIAO; Yanting LI; Xuejun FAN; Mingcheng LIU; Qiuju ZHANG

    2016-01-01

    In order to determine the optimal sowing date of ratoon rice in South Henan’s rice-growing areas,this paper performs a comparative analysis of rice growth process,seedling quality and yield of first season rice and ratoon rice under different sowing date treatments. The results show that under climatic conditions( 2014),by using dry seedling cultivation in a small plastic shed,the growth of seedling sown on February21 was affected,while the sowing treatments from March 1 to April 11 can breed normal seedlings,and in this period,the maturity period of first season rice was delayed with prolonged sowing date,and ratoon rice yield declined with prolonged sowing date( total production of rice sown on 11 March reaching a peak). Thus,it is considered that the optimal sowing date of ratoon rice in South Henan’s rice-growing areas is mid-March.

  3. Characterization of Leaf Photosynthetic Properties for No-Tillage Rice

    Institute of Scientific and Technical Information of China (English)

    CHEN Song; XIA Guo-mian; ZHAO Wei-ming; WU Fei-bo; ZHANG Guo-ping

    2007-01-01

    A study was conducted to determine the influence of no-tillage cultivation on leaf photosynthesis of rice plants under field conditions. Experiments with the treatments, no-tillage and conventional tillage were carried out at three locations (Jiaxing, Hangzhou,and Xiaoshan, Zhejiang Province, China) for two years (2005 and 2006). Grain yield was constant in Jiaxing, but slightly higher in Hangzhou and Xiaoshan under no-tillage cultivation than that under conventional cultivation. In comparison with the conventional cultivation, no-tillage cultivation showed less biomass accumulation before heading and higher capacity of matter production during grain filling. A significantly higher leaf net photosynthetic rate was observed for the plants under no-tillage than for those under conventional tillage. The fluorescence parameter (Fv/Fm) in leaf did not show any difference between the two cultivations. The effect of cultivation management on transpiration rate (Tr) and SPAD value of rice leaf was dependent on the location and year.

  4. CONDITIONAL ASIAN OPTIONS

    OpenAIRE

    Runhuan Feng; Volkmer, Hans W.

    2015-01-01

    Conditional Asian options are recent market innovations, which offer cheaper and long-dated alternatives to regular Asian options. In contrast with payoffs from regular Asian options which are based on average asset prices, the payoffs from conditional Asian options are determined only by average prices above certain threshold. Due to the limited inclusion of prices, conditional Asian options further reduce the volatility in the payoffs than their regular counterparts and have been promoted i...

  5. 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.

  6. 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 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 soil depth without restriction for rice root elongation

  7. Effects of Different Cultivation Methods on Yield and Dry Matter Production of Late Hy-brid Rice%不同栽培方式对连作晚稻产量和物质生产特征的影响

    Institute of Scientific and Technical Information of China (English)

    陆惠斌; 陈少杰

    2015-01-01

    以中熟晚粳宁81为材料,对机插、抛秧和手插3种栽培方式水稻的产量、干物质积累、茎蘖动态、成穗规律等进行比较研究。结果表明,3种栽培方式稻谷产量表现为手插>抛秧>机插,与机插相比,手插和抛秧分别增产4.25%和2.00%;在茎蘖利用上,抛秧方式的苗峰较高但成穗率低,手插和机插成穗率较高,均大于70%,机插和抛秧以利用主茎第4~7叶位上的分蘖穗为主,而手插主茎第6~8叶位上的分蘖穗对产量的贡献更大;在物质生产上,前期抛秧物质积累量较多,至拔节期干物质量抛秧>手插>机插,拔节至抽穗期,手插方式的干物质积累量显著超过抛秧,抽穗至成熟期干物质积累量机插略高于抛秧和手插。%The yield, dry matter accumulation and growth characteristics of medium maturing late japonica rice variety Ning 81 were studied under different cultivation methods. The results showed that the yield of Ning 81 with hand-transplanting was higher than that of the other two cultivation methods. Hand-transplanting and machine-transplanting rice got higher spike rate of over 70%. The tiller spikes on the main stem 4 to 7 leaf position had more contribution to yield in throw seedlings and machine-transplanting rice, while the 6 to 8 leaf position had more contribution to yield in hand-transplanting rice. Throw seedlings had more dry matter accumulation in jointing stage than others, in jointing to heading stage, hand-transplanting method performed best, in heading to maturity stage, ma-chine-transplanting method had higher dry matter accumulation.

  8. Cultivation of Pleurotus ostreatus on weed plants.

    Science.gov (United States)

    Das, Nirmalendu; Mukherjee, Mina

    2007-10-01

    Oyster mushroom, Pleurotus ostreatus (Jacq.:Fr.) Kumm. ITCC 3308 (collected from Indian Type Culture Collection, IARI, New Delhi, India, 110012) was grown on dry weed plants, Leonotis sp, Sida acuta, Parthenium argentatum, Ageratum conyzoides, Cassia sophera, Tephrosia purpurea and Lantana camara. Leonotis sp. was the best substrate in fruit body production of P. ostreatus when it was mixed with rice straw (1:1, wet wt/wet wt) for mushroom cultivation. The fruiting time for P. ostreatus was also less on Leonotis sp. than on any other weed substrates tested in the present investigation. T. purpurea was the least suited weed for oyster mushroom cultivation. The main problem of oyster mushroom cultivation on weed substrates was found to be low yield in the second flush that could be overcome by blending weed plants with rice straw. The protein contents of the fruit bodies obtained from Cassia sophera, Parthenium argentatum and Leonotis sp. were not only better than rice straw but also from the rice straw supplemented weeds.

  9. 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.

  10. Induced resistance in rice against insects.

    Science.gov (United States)

    Karban, R; Chen, Y

    2007-08-01

    Vaccinations are the mainstay of western preventive medicine, and they have been used to protect some crops against disease and insect pests. We consider rice as a model for protection using induced resistance since it is one of the most important staple crops and there have been significant new developments in: cross-resistance among rice insects, chemical pathways involved in induced resistance, sequencing the rice genome and expression of genes conferring resistance against rice insect pests. Insect attack has been found to cause lesions that kill planthopper eggs and early stages of gall midges. Damaged plants released volatiles that made them less likely to be chosen by planthoppers and more attractive to parasitoids. Chemical elicitors have been developed for dicotyledonous plants and these can induce resistance in rice, although rice does not fit models developed to explain signalling in dicots. For example, salicylic acid did not increase in rice after infection by pathogens and did not appear to be the mobile signal for induced resistance against pathogens although it was involved in induced responses to phloem-feeding insects. Jasmonic acid acted as a signal in some induced responses to pathogens as well as chewing insects. Many of the genes associated with induced resistance in rice have recently been mapped, and techniques are being developed to incorporate them into the genome of cultivated varieties. Attempts to control insect pests of rice will affect interactions with pathogens, predators and parasites, and other organisms in this agroecosystem.

  11. 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.

  12. De novo Transcriptome Assembly of Common Wild Rice (Oryza rufipogon Griff. and Discovery of Drought-Response Genes in Root Tissue Based on Transcriptomic Data.

    Directory of Open Access Journals (Sweden)

    Xin-Jie Tian

    Full Text Available The perennial O. rufipogon (common wild rice, which is considered to be the ancestor of Asian cultivated rice species, contains many useful genetic resources, including drought resistance genes. However, few studies have identified the drought resistance and tissue-specific genes in common wild rice.In this study, transcriptome sequencing libraries were constructed, including drought-treated roots (DR and control leaves (CL and roots (CR. Using Illumina sequencing technology, we generated 16.75 million bases of high-quality sequence data for common wild rice and conducted de novo assembly and annotation of genes without prior genome information. These reads were assembled into 119,332 unigenes with an average length of 715 bp. A total of 88,813 distinct sequences (74.42% of unigenes significantly matched known genes in the NCBI NT database. Differentially expressed gene (DEG analysis showed that 3617 genes were up-regulated and 4171 genes were down-regulated in the CR library compared with the CL library. Among the DEGs, 535 genes were expressed in roots but not in shoots. A similar comparison between the DR and CR libraries showed that 1393 genes were up-regulated and 315 genes were down-regulated in the DR library compared with the CR library. Finally, 37 genes that were specifically expressed in roots were screened after comparing the DEGs identified in the above-described analyses.This study provides a transcriptome sequence resource for common wild rice plants and establishes a digital gene expression profile of wild rice plants under drought conditions using the assembled transcriptome data as a reference. Several tissue-specific and drought-stress-related candidate genes were identified, representing a fully characterized transcriptome and providing a valuable resource for genetic and genomic studies in plants.

  13. 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.

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

    OpenAIRE

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

    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...

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

    Directory of Open Access Journals (Sweden)

    André Fernão Martins de Andrade

    2008-10-01

    horizon of an Entisol, from Pinheiral municipality, State of Rio de Janeiro, and the rice (Oryza Sativa L. variety utilized was the "BRS Curinga". There were applied four dosages of residue (94; 281; 844 and 2531kg ha-1 plus the testimony, without residue. The amount of zinc, cadmium and lead was determined in the root and aerial part of the rice plants. The plants cultivated in the A horizon of the Entisol presented the biggest dry biomass production, the highest zinc accumulation, and the smallest cadmium level. The plants cultivated in the Oxisol B horizon had the smallest dry biomass production, lowest zinc accumulation, and the highest level of lead. As for the Oxisol A horizon, the rice plants showed a good dry biomass production. The zinc and lead concentrated, mainly, in the roots; and cadmium in the aerial part. Based on the characteristics of the studied soils, and the fitotoxicity by lead showed in the rice plants grown on the Oxisol B horizon, the application of the siderurgical residue, is not recommended, as a zinc source for the rice crop.

  16. 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 ...

  17. What are Asian-American youth consuming? A systematic literature review.

    Science.gov (United States)

    Diep, Cassandra S; Foster, Margaret J; McKyer, E Lisako J; Goodson, Patricia; Guidry, Jeffrey J; Liew, Jeffrey

    2015-04-01

    Numerous studies have explored dietary practices among children, but there are limited studies on children of Asian background in the US. This review had three aims: (a) review literature regarding Asian-American youth's dietary behaviors, (b) critically evaluate the methodological quality of such research, and (c) provide recommendations for future nutrition-related research on Asian-American youth. The authors conducted a systematic literature review through MEDLINE (EBSCO), CINAHL Plus with Full Text (EBSCO), and Embase (Ovid); extracted descriptive data; and evaluated methodological quality. Thirteen articles were included. Major findings included: (a) frequent consumption of milk, fruit, meat, unenriched white rice, vegetables, and high-fat and high-sugar items among Asian-American children and (b) acculturation's influences on diet, resulting in Asian-American youth consuming diets characterized by both Asian and American foods. Findings from this review may inform education and promotion programs and services for Asian Americans in the US.

  18. A scheme for regional rice yield estimation using ENVISAT ASAR data

    Institute of Scientific and Technical Information of China (English)

    LE; TOAN; Thuy

    2009-01-01

    Information on rice growing areas and rice production is critical for most rice growing countries to make state and economic policies. However, the areas where rice crop is cultivated are often cloudy and rainy, which entails the use of radar remote sensing data for rice monitoring. In this paper, a practical scheme to integrate multi-temporal and multi-polarization ENVISAT ASAR data into rice crop model for regional rice yield estimation has been presented. To achieve this, rice distribution information should be obtained first by rice mapping method to retrieve rice fields from ASAR images, and then an assimilation method is applied to use the observed multi-temporal rice backscattering coefficients which are grouped for each rice pixel to re-initialize ORYZA2000 to predict rice yield. The assimilation method re-initializes the model with optimal input parameters, allowing a better temporal agreement between the rice backscattering coefficients retrieved from ASAR data and the rice backscattering coefficients simulated by a coupled model, i.e., the combination of ORYZA2000 and a semi-empirical rice backscatter model through LAI. The SCE-UA optimization algorithm is employed to determine the optimal set of input parameters. After the re-initialization, rice yield for each rice pixel is calculated, and the yield map over the area of interest is produced. The scheme was validated over Xinghua study area located in the middle of Jiangsu Province of China by using the data set of an experimental campaign carried out during the 2006 rice season. The result shows that the obtained rice yield map generally overestimates the actual rice production by 13% on average and with a root mean square error of approximately 1133 kg/ha on validation sites, but the tendency of rice growth status and spatial variation of the rice yield are well predicted and highly consistent with the actual production variation.

  19. Genetic Diversity of Wild Rice Species in Yunnan Province of China

    Institute of Scientific and Technical Information of China (English)

    CHENG Zai-quan; HUANG Xing-qi; YING Fu-you; LI Ding-qing; YU Teng-qiong; FU Jian; YAN Hui-jun; ZHONG Qiao-fang; ZHANG Dun-yu; LI Wei-jiao

    2012-01-01

    Yunnan Province of China is one of the important centers for origin and evolution of cultivated rice worldwide.Wild rice is the ancestor of the cultivated rice.Many elite traits of wild rice have widened the genetic basis in cultivated rice.However,many populations of wild rice species have disappeared in the past few years.Therefore,the current status of wild rice resources should be updated and the genetic diversity of wild rice species should be examined for further germplasm preservation and utilization.Our investigations showed that the number of natural wild rice populations declined sharply in Yunnan Province during the past few years due to various reasons.Fortunately,one population of Oryza rufipogon,three of O.officinalis and ten of O.granulata have been newly found in different ecological sites,which were confirmed by inter-simple sequence repeat (ISSR) marker analysis in this study.ISSR analysis and investigation of some important traits of nutritional values indicated that the genetic diversity of the currently existing wild rice resources in Yunnan is still rich.The demonstration of genetic diversity of wild rice by a combined use of geographical distribution,morphological traits,nutrition contents and ISSR markers would be helpful for the conservation and exploration of these important wild rice resources.

  20. Taste of Super-Dwarf Rice Cultured in Space

    Science.gov (United States)

    Hirai, Hiroaki; Kitaya, Yoshiaki

    2016-07-01

    The interest of food production for lunar base and manned Mars mission has increased recently. So far, plants cultured long duration in space were leafy vegetables, arabidopsis, wheat, barley and so on. 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. Rice symbolizes the rice-eating culture of Japan, is extremely useful as a specific cultured plant candidate of Japan in space. In the previous report, 'Kozo-no-sumika' found from seedlings in raising of seedling was introduced as a super-dwarf rice to culture in space. Considering this rice as food in space, we investigate the taste characteristics of this rice. At present, waxy 'Kozo-no-sumika' and nonwaxy 'Hosetsu dwarf' of super-dwarf rice and 'Nipponbare' of previous standard rice for sensory test are cultured in paddy field. Hereafter, we will harvest rice, investigate yield, evaluate taste.

  1. Evolutionary and social consequences of introgression of nontransgenic herbicide resistance from rice to weedy rice in Brazil.

    Science.gov (United States)

    Merotto, Aldo; Goulart, Ives C G R; Nunes, Anderson L; Kalsing, Augusto; Markus, Catarine; Menezes, Valmir G; Wander, Alcido E

    2016-08-01

    Several studies have expressed concerns about the effects of gene flow from transgenic herbicide-resistant crops to their wild relatives, but no major problems have been observed. This review describes a case study in which what has been feared in transgenics regarding gene flow has actually changed biodiversity and people's lives. Nontransgenic imidazolinone-resistant rice (IMI-rice) cultivars increased the rice grain yield by 50% in southern Brazil. This increase was beneficial for life quality of the farmers and also improved the regional economy. However, weedy rice resistant to imidazolinone herbicides started to evolve three years after the first use of IMI-rice cultivars. Population genetic studies indicate that the herbicide-resistant weedy rice was mainly originated from gene flow from resistant cultivars and distributed by seed migration. The problems related with herbicide-resistant weedy rice increased the production costs of rice that forced farmers to sell or rent their land. Gene flow from cultivated rice to weedy rice has proven to be a large agricultural, economic, and social constraint in the use of herbicide-resistant technologies in rice. This problem must be taken into account for the development of new transgenic or nontransgenic rice technologies.

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

    Directory of Open Access Journals (Sweden)

    Thi My Linh Hoang

    2016-10-01

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

  3. Research on the Key High-yielding Cultivation Techniques of Machine-transplanted Rice%机插稻高产栽培关键技术的适宜值研究

    Institute of Scientific and Technical Information of China (English)

    李伟海; 赖清云; 金军

    2015-01-01

    以2012年常州市水稻苗情哨田块的多点苗情监测数据为样本,分析归纳了种植方式、栽插丛数、播栽期、肥料运筹等因素对机插稻产量形成的影响。结果表明,机插稻较直播稻更高产,减穗增粒特征明显。机插稻获得高产的适宜栽插丛数为1.8万丛/667 m2,适宜移栽秧龄为15~20 d,氮肥运筹中基蘖肥与穗肥适宜比例为6∶4,基蘖肥中基肥与分蘖肥适宜比例为3∶7,分蘖肥最适施用时间为移栽后第2叶龄和第3叶龄。提高抽穗至成熟期干物质积累量是提高机插稻产量的重要途径。%Taking the 2012 multi-point data from rice growth monitoring fields in Changzhou city as sample, the effects of planting pattern, planting density, sowing and transplanting date, application of fertilizer on the machine-transplanted rice were analyzed and summarized. The results showed that machine-transplanted rice yield is higher than direct-seeding rice, the main feature is the ears decreasing but the grain number increasing. The optimum planting density of machine-transplanted rice is 1.8×104 points per 667 m2, the optimum transplanted seedling age is 15~20 days, the optimum proportion between the basal-tiller nitrogen and earing nitrogen is 6∶4, the optimum proportion between the basal nitrogen and tiller nitrogen is 3∶7, the optimunm period of the tiller nitrogen is the sec-ond and third leaf age after transplanted. Increasing the accumulation of biological-yield between heading stage and maturity stage is the key way to increase the yield of machine-transplanted rice.

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

    OpenAIRE

    Lizandro Ciciliano Tavares; André Pich Brunes; Daniel Andrei Robe da Fonseca; Gizele Ingrid Gadotti; Lilian Madruga de Tunes; Géri Eduardo Meneghello; Antonio Carlos Souza Albuquerque Barros

    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,...

  5. 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.

  6. 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

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

    Science.gov (United States)

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

    2015-01-01

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

  8. 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.

  9. 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.

  10. Barnyard grass-induced rice allelopathy and momilactone B.

    Science.gov (United States)

    Kato-Noguchi, Hisashi

    2011-07-01

    Here, we investigated chemical-mediated interaction between crop and weeds. Allelopathic activity of rice seedlings exhibited 5.3-6.3-fold increases when rice and barnyard grass seedlings were grown together, where there may be the competitive interference between rice and barnyard grass for nutrients. Barnyard grass is one of the most noxious weeds in rice cultivation. The momilactone B concentration in rice seedlings incubated with barnyard grass seedlings was 6.9-fold greater than that in rice seedlings incubated independently. Low nutrient growth conditions also increased allelopathic activity and momilactone B concentrations in rice seedlings. However, the increases in the low nutrient-induced allelopathic activity and momilactone B concentration were much lower than those in barnyard grass-induced allelopathic activity and momilactone B concentration. Root exudates of barnyard grass seedlings increased allelopathic activity and momilactone B concentration in rice seedlings at concentrations greater than 30 mg/L of the root exudates, and increasing the exudate concentration increased the activity and momilactone B concentration. Therefore, barnyard grass-induced allelopathic activity of rice seedlings may be caused not only by nutrient competition between two species, but also by components in barnyard grass root exudates. As momilactone B shows strong allelopathic activities, barnyard grass-induced allelopathic activity of rice may be due to the increased concentration of momilactone B in rice seedlings. The present research suggests that rice may respond to the presence of neighboring barnyard grass by sensing the components in barnyard grass root exudates and increasing allelopathic activity by production of elevated concentration of momilactone B. Thus, rice allelopathy may be one of the inducible defense mechanisms by chemical-mediated plant interaction between rice and barnyard grass, and the induced-allelopathy may provide a competitive advantage for

  11. Application Effect of Glufosinate in Direct Seeding Cultivation of Transgenic Herbicide Resistant Hybrid Rice%草铵膦在转基因抗除草剂杂交稻直播栽培中的应用效果

    Institute of Scientific and Technical Information of China (English)

    周浩; 杨益善; 唐俐; 肖国樱

    2013-01-01

    以转基因抗除草剂杂交早稻“株1S/Bar68-1”为材料,常规除草剂2次除草方式为对照,探讨了草铵膦1次除草方式在水稻直播栽培中的应用效果。结果表明:与常规除草(效果表现为千金子草害)相比,灭生性除草剂草铵膦除草对供试材料株叶形态无显著影响,但使田间杂草数量减少85.3%,减少产量损失33.1%,节约成本37.5%。“株1S/Bar68-1”直播栽培中应用草铵膦除草剂1次除草的技术要点为:草铵膦有效成分0.6 g/L,每公顷用量720~960 L(有效成分剂量432~576 g/hm2),于分蘖末期紧挨冠层均匀喷雾,冒头杂草重点喷施。%The weed control effect of glufosinate in direct seeding field of transgenic herbicide resistant early hybrid rice Zhu 1S/Bar68-1 was studied with conventional herbicide as control.The results indicated that the plant type of hybrid rice was not obviously affected , but the stems of weed were decreased by 85.3%, the grain yield loss was decreased by 33.1%and the weeding cost was decreased by 37.5%in treatment of spraying glufosinate once compared to control.The key techniques of weed control by glufosinate on direct seeding rice included that the dosage of glufosinate was 432~576 g ( a.i.)/hm2 and the glufosinate should be sprayed close to rice canopy at the end of tillering stage.

  12. Foliar Spray of Nitrogen Fertilizer on Raised Bed Increases Yield of Transplanted Aman Rice over Conventional Method

    OpenAIRE

    M. H. M. Bhuyan; Mst. R. Ferdousi; Iqbal, M. T.

    2012-01-01

    Bed planting with foliar nitrogen fertilizer application of rice production systems is very new, and research on it is still at introductory phase. Influence of foliar application of nitrogen fertilizer on growth and yield of transplanted aman rice and evaluation of water and fertilizer application efficiency of rice-fallow-rice cropping system were investigated under raised bed cultivation method. Results showed that foliar spray in bed planting method increased grain yield of transplanted a...

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

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  14. 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.

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

    Science.gov (United States)

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

    2007-01-01

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

  16. Arsenic stress in rice: redox consequences and regulation by iron.

    Science.gov (United States)

    Nath, Shwetosmita; Panda, Piyalee; Mishra, Sagarika; Dey, Mohitosh; Choudhury, Shuvasish; Sahoo, Lingaraj; Panda, Sanjib Kumar

    2014-07-01

    Arsenic (As) contamination is a serious hazard to human health and agriculture. It has emerged as an important threat for rice cultivation mainly in South Asian countries. In this study, we investigated the effect of iron (Fe) supplementation on arsenic (As(V)) induced oxidative stress responses in rice (Oryza sativa L.). Rice seedlings treated with As(V) for 24 and 48 h in presence or absence of 2.5 mM Fe after which the root and shoot tissues were harvested for analysis. The results indicate significant (p ≤ 0.05) reduction in root and shoot length/dry biomass. Supplementation of Fe showed improved growth responses under stress as compared to As(V) alone. The scanning electron microscopy (SEM) analysis of roots under As(V) treatment for 48 h showed major alterations in root structure and integrity, although no noticeable changes were observed in Fe - supplemented seedlings. Significantly high (p ≤ 0.05) accumulation of As(V) was observed in root and shoot after 24 and 48 h of stress. However, under Fe - supplementation As accumulation in root and shoot were considerably low after 24 and 48 h of As(V) treatment. The hydrogen peroxide (H2O2) and malondialdehyde (MDA) content in both root and shoot increased significantly (p ≤ 0.05) after 24 and 48 h of As(V) treatment. In Fe - supplemented seedlings, the levels of H2O2 and MDA were considerably low as compared to As(V) alone. Ascorbate (AsA) and glutathione (GSH) levels also increased significantly (p ≤ 0.05) under As(V) stress as compared to control and Fe-supplemented seedlings. Activities of catalase (CAT) and superoxide dismutase (SOD) were significantly (p ≤ 0.05) high after 24 and 48 h of As(V) treatment as compared to Fe-supplemented seedlings. The gene expression analysis revealed up-regulation of metallothionein (MT1, MT2) and nodulin 26-like intrinsic protein (NIP2;1) genes after 5d of As treatment, while their expressions were repressed under Fe-supplementation. Our results indicate that Fe

  17. Breeding and High-Yield Cultivation Technology of Good Quality Cross Combination Waxy Hybrid Rice (Oryza sativa L.ssp.japonic)%优质粳型杂交糯稻新组合选育及高产栽培技术

    Institute of Scientific and Technical Information of China (English)

    王新其; 邱美良; 郭萱昊; 殷丽青; 李茂柏; 卢有林; 沈革志

    2012-01-01

    为了快速培育高产、优质、抗性强的杂交粳型糯稻新种质,选用综合农艺性状优良的粳型寒丰糯(HFwx),将其与同型的寒丰不育系(HFA)进行育性转换,获得了粳型糯质新不育系寒丰糯(HFwxA),并与自主选育的粳型糯质恢复系配组育成了杂交粳型糯稻新组合(HFwxA/N2R).小区和示范试验结果表明,选育获得的杂交糯稻新组合具有高产、优质、抗性强等特点,具有生产应用前景.杂交糯稻新组合的生育特征特性和高产栽培技术的试验总结,对杂交糯稻的推广应用和产业化发展都具有十分重要的参考意义.%In order to quick breed a new high yield,high quality and strong resistance hybrid glutinous rice germplasm (Oryza sativa L. Ssp. Japonic) ,japonica rice (HFwxB) with good comprehensive agronomic was obtained and translated into HFwxA by using it's the same type of CMS (HFA), a new hybrid glutinous rice germplasm was gotten and named Nuoza 2 (HFwxA/N2R). The small field test and demonstration trials indicated that the new combination of Oryza sativa L. Ssp. Japonic was high-yield, good quality and strong resistance, which could be applied and extended. The high-yield cultivation techniques and breeding characters of the hybrid new combination are very useful for its application and industrialization development.

  18. 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

  19. Characteristics of the short rachillae of rice from archaeological sites dating to 7000 years ago

    Institute of Scientific and Technical Information of China (English)

    ZHENG YunFei; SUN GuoPing; CHEN XuGao

    2007-01-01

    The abscission layer formed on a pedicel situated at the basal part of a short rachilla is an important characteristic for discriminating between wild,japonica,and indica rice.The short rachillae of paddy rice grains excavated from the Kuahuqiao,Luojiajiao,and Tianluoshan sites,located in the lower eaches of the Yangtze River and dating to 7000 years old,were observed.The results showed that the short rachillae could be divided into two types:a wild type and japonica type.These results indicated that the rice had been domesticated,but was a primitive cultivated rice that retained some of the characteristics of wild rice.The results also suggested that the rice was changing to resemble japonica type rice.Based on the ratios of wild and japonica types,it was inferred that rice domestication began 10000 years ago.

  20. 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

  1. 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

  2. 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.

  3. Effects of soaking, germination and fermentation on phytic acid, total and in vitro soluble zinc in brown rice

    NARCIS (Netherlands)

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

    2008-01-01

    Rice is an important staple food in Asian countries. In rural areas it is also a major source of micronutrients. Unfortunately, the bioavailability of minerals, e.g. zinc from rice, is low because it is present as an insoluble complex with food components such as phytic acid. We investigated the eff

  4. 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...

  5. 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.

  6. 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...

  7. 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...

  8. Archaeological and genetic insights into the origins of domesticated rice.

    Science.gov (United States)

    Gross, Briana L; Zhao, Zhijun

    2014-04-29

    Rice (Oryza sativa) is one of the most important cereal grains in the world today and serves as a staple food source for more than half of the world's population. Research into when, where, and how rice was brought into cultivation and eventually domesticated, along with its development into a staple food source, is thus essential. These questions have been a point of nearly continuous research in both archaeology and genetics, and new information has continually come to light as theory, data acquisition, and analytical techniques have advanced over time. Here, we review the broad history of our scientific understanding of the rice domestication process from both an archaeological and genetic perspective and examine in detail the information that has come to light in both of these fields in the last 10 y. Current findings from genetics and archaeology are consistent with the domestication of O. sativa japonica in the Yangtze River valley of southern China. Interestingly, although it appears rice was cultivated in the area by as early 8000 BP, the key domestication trait of nonshattering was not fixed for another 1,000 y or perhaps longer. Rice was also cultivated in India as early as 5000 BP, but the domesticated indica subspecies currently appears to be a product of the introgression of favorable alleles from japonica. These findings are reshaping our understanding of rice domestication and also have implications for understanding the complex evolutionary process of plant domestication.

  9. 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.

  10. RICD: A rice indica cDNA database resource for rice functional genomics

    Directory of Open Access Journals (Sweden)

    Zhang Qifa

    2008-11-01

    Full Text Available Abstract Background The Oryza sativa L. indica subspecies is the most widely cultivated rice. During the last few years, we have collected over 20,000 putative full-length cDNAs and over 40,000 ESTs isolated from various cDNA libraries of two indica varieties Guangluai 4 and Minghui 63. A database of the rice indica cDNAs was therefore built to provide a comprehensive web data source for searching and retrieving the indica cDNA clones. Results Rice Indica cDNA Database (RICD is an online MySQL-PHP driven database with a user-friendly web interface. It allows investigators to query the cDNA clones by keyword, genome position, nucleotide or protein sequence, and putative function. It also provides a series of information, including sequences, protein domain annotations, similarity search results, SNPs and InDels information, and hyperlinks to gene annotation in both The Rice Annotation Project Database (RAP-DB and The TIGR Rice Genome Annotation Resource, expression atlas in RiceGE and variation report in Gramene of each cDNA. Conclusion The online rice indica cDNA database provides cDNA resource with comprehensive information to researchers for functional analysis of indica subspecies and for comparative genomics. The RICD database is available through our website http://www.ncgr.ac.cn/ricd.

  11. Collection and Comparative Analysis of 1888 Full-length cDNAs from Wild Rice Oryza rufipogon Griff. W1943

    OpenAIRE

    Lu, Tingting; Yu, Shuliang; Fan, Danlin; Mu, Jie; Shangguan, Yingying; Wang, Zixuan; Minobe, Yuzo; Lin, Zhixin; Han, Bin

    2008-01-01

    A huge amount of cDNA and EST resources have been developed for cultivated rice species Oryza sativa; however, only few cDNA resources are available for wild rice species. In this study, we isolated and completely sequenced 1888 putative full-length cDNA (FLcDNA) clones from wild rice Oryza rufipogon Griff. W1943 for comparative analysis between wild and cultivated rice species. Two cDNA libraries were constructed from 3-week-old leaf samples under either normal or cold-treated conditions. Ho...

  12. The Representation of Older People in East Asian Television Advertisements.

    Science.gov (United States)

    Prieler, Michael; Ivanov, Alex; Hagiwara, Shigeru

    2016-11-15

    In this study, 432 television advertisements from Hong Kong, Japan, and South Korea were analyzed to determine their representations of older people. Findings demonstrate that in East Asian advertisements, older people are highly underrepresented, appear in major roles, mostly alongside younger people, and older men clearly outnumber older women. The other variables investigated (i.e., setting and product categories) led to no conclusive findings for the three societies. In short, our study, employing ethnolinguistic vitality theory to analyze television advertisements, demonstrates how East Asian societies greatly marginalize older people. Potential effects of such representations are discussed using social cognitive theory and cultivation theory.

  13. 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.

  14. NITROUS OXIDE EMISSION AND NITROGEN UPTAKE AFFECTED BY SOIL AMENDMENT AND NEMATICIDE IN RAINFED RICE SOILS AT CENTRAL JAVA

    Directory of Open Access Journals (Sweden)

    A. Wihardjaka

    2013-10-01

    Full Text Available Rice cultivation is one of the antropogenic sources of nitrous oxide (N2O emission that is produced by microbiological nitrification-denitrification processes. Incorporating soil amendment in rainfed rice soil attempted to increase soil productivity, while nematicide application aimed to maintain root growth system. Incorporating soil amendment and nematicide application are predicted to suppress N2O production in lowland rice. The objective of this research was to study the interaction of soil organic amendment and nematicide on N2O emission and nitrogen uptake from rainfed lowland rice soils. A field experiment was conducted in rainfed lowland rice soils during 2010/2011 wet season (direct seeded rice and 2011 dry season (transplanted rice. The 3 x 3 factorial trial was arranged in a randomized completely block design with three replications. The first factor was soil amendment consisted of without rice straw, fresh rice straw and composted rice straw. The second factor was nematicide application consisted of without nematicide, neemcake and carbofuran. Variables measured were N2O flux, rice grain yield and nitrogen uptake. Incorporation of fresh and composted rice straws reduced N2O flux about 49.2% and 59.9% in transplanted rice, and 32.9% and 28.2% in direct seeded rice, respectively. The neemcake application reduced N2O emission about 44-50%, while carbofuran application decreased N2O emission by 23-35%. Neemcake has a good potential as nitrification inhibitor of N2O emission, so the neem trees have a prospect to be cultivated intensively. The reduction of N2O emission was effective in direct seeded rice system with the application of neemcake and fresh rice straw, however, in transplanted rice system it was effective with neemcake and composted rice straw applications.

  15. 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.

  16. Improvement of the Value of Green Manure via Mixed Hairy Vetch and Barley Cultivation in Temperate Paddy Soil

    NARCIS (Netherlands)

    Hwang, Hyun Young; Kim, Gil Won; Lee, Yong Bok; Kim, Pil Joo; Kim, Sang Yoon

    2015-01-01

    Legume hairy vetch and non-legume barley mixtures are broadly cultivated to improve the value of cover crops in mono-rice paddies. Nevertheless, the effects of mixing conditions of the two cover crops on biomass and nutrient productivities and on the yield characteristics of subsequent rice crops ha

  17. 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...

  18. The Asian war bow

    CERN Document Server

    Nieminen, Timo A

    2011-01-01

    The bow is one of the earliest complex machines, a prime example of the storage and transfer of energy. The physics of the bow illuminates compromises and design choices made in Asian military archery.

  19. Asian Art on Display

    DEFF Research Database (Denmark)

    Borggreen, Gunhild Ravn

    2010-01-01

    Med udgangspunkt i seminaret Visualising Asian Modernity diskuteres forholdet mellem antropologi og samtidskunst i lyset af hvorledes asiatisk kunst fremvises og formidles i vestlig og dansk sammenhæng....

  20. 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 ...

  1. 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.

  2. Classification of cultivated plants.

    NARCIS (Netherlands)

    Brandenburg, W.A.

    1986-01-01

    Agricultural practice demands principles for classification, starting from the basal entity in cultivated plants: the cultivar. In establishing biosystematic relationships between wild, weedy and cultivated plants, the species concept needs re-examination. Combining of botanic classification, based

  3. Red Yeast Rice

    Science.gov (United States)

    Nguyen, Thu; Karl, Mitchell; Santini, Antonello

    2017-01-01

    Red yeast rice (RYR), produced by the fermentation of the Monascus purpureus mold, has been used for a long time in Asian cuisine and traditional medicine. It consists of multiple bioactive substances, including monacolins, which potentially can be used as a nutraceutical. Monacolin K, which is chemically identical to lovastatin, has been recognized as responsible for the cholesterol-reducing effect of this compound. While the European Food Safety Authority maintains that the use of monacolin K from RYR preparations of at least 10 mg can produce a normal blood cholesterol level, the United States Food and Drug Administration considers monacolin K, due to its similarity with lovastatin, an unapproved drug, and therefore marketing of products that label the monacolin content is prohibited. This mini-review summarizes the benefit of RYR in hyperlipidemia, maintains RYR use as a food, and addresses the importance of regulation regarding RYR and the need for clinical data and clear label information for consumers with reference to a toxin-free, non-augmented, standardized amount of monacolins. PMID:28257063

  4. Red Yeast Rice

    Directory of Open Access Journals (Sweden)

    Thu Nguyen

    2017-03-01

    Full Text Available Red yeast rice (RYR, produced by the fermentation of the Monascus purpureus mold, has been used for a long time in Asian cuisine and traditional medicine. It consists of multiple bioactive substances, including monacolins, which potentially can be used as a nutraceutical. Monacolin K, which is chemically identical to lovastatin, has been recognized as responsible for the cholesterolreducing effect of this compound. While the European Food Safety Authority maintains that the use of monacolin K from RYR preparations of at least 10 mg can produce a normal blood cholesterol level, the United States Food and Drug Administration considers monacolin K, due to its similarity with lovastatin, an unapproved drug, and therefore marketing of products that label the monacolin content is prohibited. This mini-review summarizes the benefit of RYR in hyperlipidemia, maintains RYR use as a food, and addresses the importance of regulation regarding RYR and the need for clinical data and clear label information for consumers with reference to a toxin-free, nonaugmented, standardized amount of monacolins.

  5. Contribution of seedling vigour and anoxia/hypoxia-responsive genes to submergence tolerance in Vietnamese lowland rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Hien Thi Thu Vu

    2016-09-01

    Full Text Available A direct-seeded rice cultivation system has been widely adopted in Asian countries. Optimum germination and vigorous seedling growth under submergence are key traits for the practice of direct seeding. We studied the post-germination seedling vigour in Vietnamese lowland rice accessions based on three bio-parameters, shoot elongation growth under five-day submergence in water-filled test-tubes, seedling recovery rate five days after transferring submerged seedlings to pots with soil and seedling survival rate 21 days after sowing seeds in nursery beds and immediate incubation under submergence. A large diversity was found in seedling vigour thus estimated among the accessions. Significantly high correlations were observed among all three bio-parameters, verifying the contribution of seedling vigour to the manifestation of submergence tolerance at this critical stage of rice development. To examine the roles of anoxia/hypoxia-responsive genes, the expression of 17 candidate genes was studied by reverse transcription polymerase chain reaction (RT-PCR and compared between selected vigorous and non-vigorous groups of accessions. Transcripts of all but two genes showed marked accumulation in submerged seedlings. No differences, however, were found between the two contrasting groups. The observed common and coordinate expression of anoxia/hypoxia-induced genes suggests that they might assume roles in attaining baseline tolerance against submergence stress. It was also suggested that some unknown genetic factors are operating in determining cultivar/genotype-specific levels of submergence tolerance as assessed by post-germination seedling vigour.

  6. 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.

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

    OpenAIRE

    Todaka, Daisuke; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    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 ...

  8. 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

  9. 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

  10. 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.

  11. Genetic variation architecture of mitochondrial genome reveals the differentiation in Korean landrace and weedy rice

    Science.gov (United States)

    Tong, Wei; He, Qiang; Park, Yong-Jin

    2017-01-01

    Mitochondrial genome variations have been detected despite the overall conservation of this gene content, which has been valuable for plant population genetics and evolutionary studies. Here, we describe mitochondrial variation architecture and our performance of a phylogenetic dissection of Korean landrace and weedy rice. A total of 4,717 variations across the mitochondrial genome were identified adjunct with 10 wild rice. Genetic diversity assessment revealed that wild rice has higher nucleotide diversity than landrace and/or weedy, and landrace rice has higher diversity than weedy rice. Genetic distance was suggestive of a high level of breeding between landrace and weedy rice, and the landrace showing a closer association with wild rice than weedy rice. Population structure and principal component analyses showed no obvious difference in the genetic backgrounds of landrace and weedy rice in mitochondrial genome level. Phylogenetic, population split, and haplotype network evaluations were suggestive of independent origins of the indica and japonica varieties. The origin of weedy rice is supposed to be more likely from cultivated rice rather than from wild rice in mitochondrial genome level. PMID:28256554

  12. Genetic variation architecture of mitochondrial genome reveals the differentiation in Korean landrace and weedy rice.

    Science.gov (United States)

    Tong, Wei; He, Qiang; Park, Yong-Jin

    2017-03-03

    Mitochondrial genome variations have been detected despite the overall conservation of this gene content, which has been valuable for plant population genetics and evolutionary studies. Here, we describe mitochondrial variation architecture and our performance of a phylogenetic dissection of Korean landrace and weedy rice. A total of 4,717 variations across the mitochondrial genome were identified adjunct with 10 wild rice. Genetic diversity assessment revealed that wild rice has higher nucleotide diversity than landrace and/or weedy, and landrace rice has higher diversity than weedy rice. Genetic distance was suggestive of a high level of breeding between landrace and weedy rice, and the landrace showing a closer association with wild rice than weedy rice. Population structure and principal component analyses showed no obvious difference in the genetic backgrounds of landrace and weedy rice in mitochondrial genome level. Phylogenetic, population split, and haplotype network evaluations were suggestive of independent origins of the indica and japonica varieties. The origin of weedy rice is supposed to be more likely from cultivated rice rather than from wild rice in mitochondrial genome level.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Nutritional constituents and health benefits of wild rice (Zizania spp.).

    Science.gov (United States)

    Surendiran, Gangadaran; Alsaif, Maha; Kapourchali, Fatemeh Ramezani; Moghadasian, Mohammed H

    2014-04-01

    Wild rice (Zizania spp.) seems to have originated in North America and then dispersed into Eastern Asia and other parts of the world. Nutritional analysis shows that wild rice is rich in minerals, vitamins, protein, starch, dietary fiber, and various antioxidant phytochemicals, while it is low in fat. Wild rice has been recognized as a whole grain by the US Food and Drug Administration; in the North American marketplace it is currently sold as and considered to be a health-promoting food. Recent scientific studies have revealed antioxidant and lipid-lowering properties of wild rice, while others have documented cardiovascular benefits associated with the long-term consumption of wild rice in experimental settings. The present review article summarizes various features of wild rice and its cultivation, including its plantation, harvest, nutritional composition, and biological properties. While evidence for the cardiovascular benefits of wild rice consumption is accumulating, additional studies are warranted to determine the clinical benefits of regular consumption of wild rice.

  19. 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.

  20. 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.

  1. Discussion on the Origin of Rice%问说水稻起源

    Institute of Scientific and Technical Information of China (English)

    朱元军

    2016-01-01

    本文阐述了稻的起源学说,基于江西省万年县野生稻到栽培稻植硅石和花粉完整驯化遗存的考古发现,提出了万年县是中国稻作的起源地之一,为研究中国栽培稻的起源提供了重要依据。%This paper elucidated the origin theory of cultivated rice, based on the archaeological discovery of wild paddy and cultivat-ed rice opal phytolith and pollen completion domestication in Wannian County, Jiangxi Province. It proposed that Wannian County is one of the birthplace of cultivated paddy in China, which provided important foundation for research the origin of Chinese cultivated rice.

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

    OpenAIRE

    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...

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. The Complex History of the Domestication of Rice

    Science.gov (United States)

    Sweeney, Megan; McCouch, Susan

    2007-01-01

    Background Rice has been found in archaeological sites dating to 8000 bc, although the date of rice domestication is a matter of continuing debate. Two species of domesticated rice, Oryza sativa (Asian) and Oryza glaberrima (African) are grown globally. Numerous traits separate wild and domesticated rices including changes in: pericarp colour, dormancy, shattering, panicle architecture, tiller number, mating type and number and size of seeds. Scope Genetic studies using diverse methodologies have uncovered a deep population structure within domesticated rice. Two main groups, the indica and japonica subspecies, have been identified with several subpopulations existing within each group. The antiquity of the divide has been estimated at more than 100 000 years ago. This date far precedes domestication, supporting independent domestications of indica and japonica from pre-differentiated pools of the wild ancestor. Crosses between subspecies display sterility and segregate for domestication traits, indicating that different populations are fixed for different networks of alleles conditioning these traits. Numerous domestication QTLs have been identified in crosses between the subspecies and in crosses between wild and domesticated accessions of rice. Many of the QTLs cluster in the same genomic regions, suggesting that a single gene with pleiotropic effects or that closely linked clusters of genes underlie these QTL. Recently, several domestication loci have been cloned from rice, including the gene controlling pericarp colour and two loci for shattering. The distribution and evolutionary history of these genes gives insight into the domestication process and the relationship between the subspecies. Conclusions The evolutionary history of rice is complex, but recent work has shed light on the genetics of the transition from wild (O. rufipogon and O. nivara) to domesticated (O. sativa) rice. The types of genes involved and the geographic and genetic distribution of

  8. 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

  9. 云南传统栽培稻品种waxy基因序列分析%Sequence Analysis of waxy Gene of Yunnan Rice Landrace

    Institute of Scientific and Technical Information of China (English)

    李枝桦; 陆春明; 卢宝荣; 王云月

    2011-01-01

    栽培稻是全球最重要的粮食作物之一,waxy基因对栽培稻的品质改良研究具有重要意义.云南是亚洲栽培稻多样性分布中心之一,传统品种丰富.本研究依据云南不同稻区、不同海拔选取99份传统栽培稻品种,对waxy基因序列进行分析.结果显示,供试品种中waxy基因序列包含36个单倍型,其中52个品种存在23 bp碱基的插入,而47个品种存在23 bp碱基的缺失;糯稻waxy基因第一内含子5’端既有G也有T碱基,剪切位点以T为主,粘稻剪切位点以G为主.7个糯稻地方品种的第一内含子5'端为G,同时第二外显子存在23 bp碱基的缺失,与前人的研究结果有所不同,表明云南栽培稻waxy基因单核苷酸多态性高,单倍型多,稻种资源丰富,为挖掘和利用优异糯性基因及品质改良提供了宝贵材料,为云南传统栽培稻种质资源的利用与保护提供了理论依据.%Rice (Oryza saliva L.) is the major staple food of the world's population, waxy gene is the key gene that determines the starch composition, which is very important of the quality improvement of rice. Yunnan province is one the center of diversity of Asian cultivated rice and many traditional rice varieties were found in Yunnan province. DNA sequence analysis of the 99 Yunnan rice landrace varieties from different attitude and rice planting area. The sequence characterization confirmed that 36 haplotypes of the waxy gene found in the 99 varieties. 52 varieties contain a "23 bp" insertion in the waxy gene, but 47 varieties have a "23 bp" deletion. There are seven glutinous rice varieties that have G/T mutation and the "23 bp" deletion. Yunnan rice varieties had rich SNPs and haploids, which provided valuable rice resource for waxy gene utilization and rice quality improvement. This study provided the scientific basis for conservation of Yunnan rice landrace resources.

  10. Scrolling and Strolling, Asian Style

    Science.gov (United States)

    Sterling, Joan

    2012-01-01

    In this article, the author describes a lesson on Asian cultures. Asian cultures demonstrate respect for nature through their art. Students learned how to use Asian brush techniques and designs to create scrolls. They also learned how to write Haiku, a three-line form of poetry that uses a pattern of syllables.

  11. South Asian Diaspora in Scandinavia

    DEFF Research Database (Denmark)

    Singla, Rashmi

    2005-01-01

    and exclusion, individualization and interdependency, these relationships are delineated on the basis of two empirical projects, combined with an array of secondary sources. South Asian youth are becoming a part of the receiving society along with developing their complex diaspora identities through strategies...... societies, South Asian countries and the South Asian diaspora living in Scandinavia....

  12. 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

  13. 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...

  14. 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.

  15. HIV Among Asians

    Science.gov (United States)

    ... Prevention VIH En Español Get Tested Find an HIV testing site near you. Enter ZIP code or city Follow HIV/AIDS CDC HIV CDC HIV/AIDS See RSS | ... Email Updates on HIV Syndicated Content Website Feedback HIV Among Asians Format: Select One File [143K] Recommend ...

  16. 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

  17. A New Asian Alliance

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The inauguration of the China-ASEAN Free Trade Area caps 10 years of fruitful efforts It was not only the birth of a new decade. January 1 also witnessed a day of celebration on the mainland and beyond after Beijing and its partners in the Association of Southeast Asian Nations (ASEAN) fully established the China-ASEAN Free Trade Area (CAFTA).

  18. 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.

  19. 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

  20. Life cycle GHG evaluation of organic rice production in northern Thailand.

    Science.gov (United States)

    Yodkhum, Sanwasan; Gheewala, Shabbir H; Sampattagul, Sate

    2017-03-09

    Greenhouse gas (GHG) emission is one of the serious international environmental issues that can lead to severe damages such as climate change, sea level rise, emerging disease and many other impacts. Rice cultivation is associated with emissions of potent GHGs such as methane and nitrous oxide. Thai rice has been massively exported worldwide however the markets are becoming more competitive than ever since the green market has been hugely promoted. In order to maintain the same level or enhance of competitiveness, Thai rice needs to be considered for environmentally conscious products to meet the international environmental standards. Therefore, it is necessary to evaluate the greenhouse gas emissions throughout the life cycle of rice production in order to identify the major emission sources and possible reduction strategies. In this research, the rice variety considered is Khao Dawk Mali 105 (KDML 105) cultivated by organic practices. The data sources were Don-Chiang Organic Agricultural Cooperative (DCOAC), Mae-teang district, Chiang Mai province, Thailand and the Office of Agricultural Economics (OAE) of Thailand with onsite records and interviews of farmers in 2013. The GHG emissions were calculated from cradle-to-farm by using the Life Cycle Assessment (LCA) approach and the 2006 IPCC Guideline for National Greenhouse Gas Inventories. The functional unit is defined as 1 kg of paddy rice at farm gate. Results showed that the total GHG emissions of organic rice production were 0.58 kg CO2-eq per kg of paddy rice. The major source of GHG emission was from the field emissions accounting for 0.48 kg CO2-eq per kg of paddy rice, about 83% of total, followed by land preparation, harvesting and other stages (planting, cultivation and transport of raw materials) were 9, 5 and 3% of total, respectively. The comparative results clearly showed that the GHG emissions of organic paddy rice were considerably lower than conventional rice production due to the advantages

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. Farmer’s Knowledge and Perceptions on Rice Insect Pests and Their Management in Uganda

    Directory of Open Access Journals (Sweden)

    Simon Alibu

    2016-08-01

    Full Text Available Rice is a new crop in Uganda, but has quickly grown in importance. Between 2000 and 2010, total area under rice cultivation in the country grew by 94% from 140,000 ha. Changes in the agro ecosystem due to expansion in rice area may have altered the pest status of rice insect pests. However, far too little attention has been paid to assessing the prevalence and importance of rice insect-pests in Uganda. In this study, we interviewed 240 lowland-rice farming households from eight districts within the north, east and central regions of Uganda about their perceived insect-pest problems and control measures employed, if any. A semi-structured questionnaire was used. The farmers ranked rice insect pests as the most important biotic constraint in rice production, with stem borers and the African rice gall midge (AfRGM perceived to be the 1st and 2nd most detrimental insect pests, respectively. In spite of this, only 36% of the respondents could positively identify symptoms of AfRGM damage on rice plants, while 64% were familiar with stem borer damage. Over 60% of interviewed farmers expressed confidence in the effectiveness of insecticides for controlling rice insect pests. Cultural control measures were not popular among the farmers.

  6. History of Asian American psychology.

    Science.gov (United States)

    Leong, Frederick T L; Okazaki, Sumie

    2009-10-01

    An overview of the history of Asian American psychology is provided by reviewing the context for the development of the field as well as the early founding of the Asian American Psychological Association (AAPA). The presidents of AAPA as well as key events and conferences are noted. The involvement of AAPA leaders in national mental health policies and activities are reviewed. The substantive areas of Asian American psychology and the education and training of Asian American psychologists are also discussed. The article ends with some comments about the future of Asian American psychology.

  7. Collection and comparative analysis of 1888 full-length cDNAs from wild rice Oryza rufipogon Griff. W1943.

    Science.gov (United States)

    Lu, Tingting; Yu, Shuliang; Fan, Danlin; Mu, Jie; Shangguan, Yingying; Wang, Zixuan; Minobe, Yuzo; Lin, Zhixin; Han, Bin

    2008-10-01

    A huge amount of cDNA and EST resources have been developed for cultivated rice species Oryza sativa; however, only few cDNA resources are available for wild rice species. In this study, we isolated and completely sequenced 1888 putative full-length cDNA (FLcDNA) clones from wild rice Oryza rufipogon Griff. W1943 for comparative analysis between wild and cultivated rice species. Two cDNA libraries were constructed from 3-week-old leaf samples under either normal or cold-treated conditions. Homology searching of these cDNA sequences revealed that >96.8% of the wild rice cDNAs were matched to the cultivated rice O. sativa ssp. japonica cv. Nipponbare genome sequence. However, sequence. The comparative analysis showed that O. rufipogon W1943 had greater similarity to O. sativa ssp. japonica than to ssp. indica cultivars. In addition, 17 novel rice cDNAs were identified, and 41 putative tissue-specific expression genes were defined through searching the rice massively parallel signature-sequencing database. In conclusion, these FLcDNA clones are a resource for further function verification and could be broadly utilized in rice biological studies.

  8. Rice Price under Pressure

    Institute of Scientific and Technical Information of China (English)

    Liu Xinwen

    2008-01-01

    @@ Early in April, the FOB (Free on Board) value of rice exported from Bangkok, Thailand, the biggest rice exporter of the world, surged to a new high of US$730per ton, representing an increase of 70 percent in recent years, and setting a new record over the past 34 years of Thailand rice exports.

  9. 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.

  10. 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.

  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. Rice peasants and rice research in Colombia

    NARCIS (Netherlands)

    Spijkers, P.A.N.M.

    1983-01-01

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

  13. [Molecular ecological basis of high-yielding formation of rice and its application].

    Science.gov (United States)

    Lin, Wenxiong; Liang, Kangjing; Guo, Yuchun; He, Huaqin; Wang, Jingyuan; Liang, Yiyuan; Chen, Fangyu

    2003-12-01

    This paper introduced the developmental genetics and its molecular ecological basis of high yielding formation of rice in the past decade, and analyzed the advantage and the shortage of comparative physiological approach traditionally used in the research work on crop cultivation. It was emphasized to actively introduce the research contents and its methodology from relative disciplines to deeply understand the scientific issue, and suggested that the key to realize stable and high yielding of rice was to develop a rational cultivation system based on the properties of genetic effects on the traits in different developmental stages by controlling and regulating the traits governed by dominant effect genes and additive effect genes x environment in same direction, which was considered as the main characteristics and the technological innovation of modern crop genetic ecological cultivation science. Finally, the development trend of crop cultivation science shifting to molecular crop cultivation science was predicted and discussed.

  14. 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

  15. 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.

  16. 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.

  17. Morphogenesis of rice and Arabidopsis seedlings in space.

    Science.gov (United States)

    Hoson, T; Soga, K; Mori, R; Saiki, M; Wakabayashi, K; Kamisaka, S; Kamigaichi, S; Aizawa, S; Yoshizaki, I; Mukai, C; Shimazu, T; Fukui, K; Yamashita, M

    1999-12-01

    Seedlings of rice (Oryza saliva L.) and Arabidopsis (A. thaliana L.) were cultivated for 68.5 hr in the RICE experiment on board during Space Shuttle STS 95 mission, and changes in their growth and morphology were analyzed. Microgravity in space stimulated elongation growth of both rice coleoptiles and Arabidopsis hypocotyls by making their cell walls extensible. In space, rice coleoptiles showed an inclination toward the caryopsis in the basal region and also a spontaneous curvature in the same direction in the elongating region. These inclinations and curvatures were more prominent in the Koshihikari cultivar compared to a dwarf cultivar, Tan-ginbozu. Rice roots elongated in various directions including into the air on orbit, but two thirds of the roots formed a constant angle with the axis of the caryopsis. In space, Arabidopsis hypocotyls also elongated in a variety of directions and about 10% of the hypocotyls grew into the agar medium. No clear curvatures were observed in the elongating region of Arabidopsis hypocotyls. Such a morphology of both types of seedlings was fundamentally similar to that observed on a 3 D clinostat. Thus, it was confirmed by the RICE experiment that rice and Arabidopsis seedlings perform an automorphogenesis under not only simulated but also true microgravity conditions.

  18. 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.

  19. 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

  20. 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...

  1. Mood disorders in Asians.

    Science.gov (United States)

    Yeung, Albert; Chang, Doris

    2014-02-01

    Mood disorders are disorders that have a disturbance in mood as the predominant feature. They are common psychiatric disorders and are associated with significant distress and functional impairment. As the theory of mood disorders is based on the philosophy of mind/body dichotomy in the West, it contradicts the holistic tradition of medicine in the East. This may partially explain why many Asians with mood disorders emphasize their physical symptoms in discussions with their treatment providers. In the development of the DSM and ICD diagnostic systems, it is presumed that the diagnostic categories are applicable to all races and ethnicities. Similarly, many consider pharmacological and psychological treatment approaches to mood disorders universally applicable. To effectively treat Asians with mood disorders, clinicians need to customize biological and psychosocial interventions in consideration of patients' potential genetic and cultural differences.

  2. 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.

  3. 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.

  4. 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.

  5. Glycemic index of American-grown jasmine rice classified as high.

    Science.gov (United States)

    Truong, Teresa H; Yuet, Wei Cheng; Hall, Micki D

    2014-06-01

    The primary objective was to determine the glycemic index (GI) of jasmine rice grown in the United States (US). Secondary objective was to compare the GI of US grown jasmine rice to those grown in Thailand. Twelve healthy subjects were served all four brands of jasmine rice and a reference food (glucose), each containing 50 g of available carbohydrate. Fingerstick blood glucose was measured at 0, 15, 30, 45, 60, 90, and 120 min after consumption following a fasting state. The GI was calculated using the standard equation. The GI values for test foods ranged from 96 to 116 and were all classified as high GI foods. No difference in GI was found between American-grown and Thailand-grown jasmine rice. Although not statistically significant, observations show glycemic response among Asian American participants may be different. GI should be considered when planning meals with jasmine rice as the main source carbohydrate.

  6. Phylogenetic and functional diversity of denitrifying bacteria isolated from various rice paddy and rice-soybean rotation fields.

    Science.gov (United States)

    Tago, Kanako; Ishii, Satoshi; Nishizawa, Tomoyasu; Otsuka, Shigeto; Senoo, Keishi

    2011-01-01

    Denitrifiers can produce and consume nitrous oxide (N(2)O). While little N(2)O is emitted from rice paddy soil, the same soil produces N(2)O when the land is drained and used for upland crop cultivation. In this study, we collected soils from two types of fields each at three locations in Japan; one type of field had been used for continuous cultivation of rice and the other for rotational cultivation of rice and soybean. Active denitrifiers were isolated from these soils using a functional single-cell isolation method, and their taxonomy and denitrifying properties were examined. A total of 110 denitrifiers were obtained, including those previously detected by a culture-independent analysis. Strains belonging to the genus Pseudogulbenkiania were dominant at all locations, suggesting that Pseudogulbenkiania denitrifiers are ubiquitous in various rice paddy soils. Potential denitrifying activity was similar among the strains, regardless of the differences in taxonomic position and soil of origin. However, relative amounts of N(2) in denitrification end products varied among strains isolated from different locations. Our results also showed that crop rotation had minimal impact on the functional diversity of the denitrifying strains. These results indicate that soil and other environmental factors, excluding cropping systems, could select for N(2)-producing denitrifiers.

  7. 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.

  8. [Photosynthetic and water physiological characteristics of weedy rice in northern China].

    Science.gov (United States)

    Gao, Qi; Ma, Dian-Rong; Kong, De-Xiu; Wang, Wen-Jia; Tong, Hui; Zhao, Ming-Hui; Xu, Zheng-Jin; Chen, Wen-Fu

    2013-11-01

    Weedy rice is an important germplasm source of rice, which has the characteristics of cold-, drought-, and barren tolerance. Taking 88 accessions of weedy rice and 4 varieties of cultivated rice in northern China as test materials, this paper studied the photosynthetic characteristics (photosynthetic rate, transpiration rate, and stomatal conductance), water physiological characteristics, and their interrelationships of weedy rice in northern China. There existed greater differences in the photosynthetic and water physiological characteristics among the weedy rice accessions, possessing abundant diversity. The photosynthetic rate of the accessions was from 12.47 micromol CO2 x m(-2) x s(-1) to 28.67 micromol CO2 X m(-2) x s(-1), and the instantaneous water use efficiency was from 1.39 mg x g(-1) to 3.40 mg x g(-1). Among the photosynthetic parameters, intercellular CO2 concentration had the smallest variable coefficient, while stomatal conductance had the largest one. The photosynthetic rate had significant conic relationships with transpiration rate and stomatal conductance, and had a linear relationship with intercellular CO2 concentration. The significant conic relationships also existed between the instantaneous water use efficiency and the transpiration rate and stomatal conductance. The excellent features of weedy rice could be used to improve the cultivated rice varieties.

  9. Increased greenhouse-gas intensity of rice production under future atmospheric conditions

    Science.gov (United States)

    van Groenigen, Kees Jan; van Kessel, Chris; Hungate, Bruce A.

    2013-03-01

    Increased atmospheric CO2 and rising temperatures are expected to affect rice yields and greenhouse-gas (GHG) emissions from rice paddies. This is important, because rice cultivation is one of the largest human-induced sources of the potent GHG methane (CH4) and rice is the world's second-most produced staple crop. The need for meeting a growing global food demand argues for assessing GHG emissions from croplands on the basis of yield rather than land area, such that efforts to reduce GHG emissions take into consideration the consequences for food production. However, it is unclear whether or how the GHG intensity (that is, yield-scaled GHG emissions) of cropping systems will be affected by future atmospheric conditions. Here we show, using meta-analysis, that increased atmospheric CO2 (ranging from 550 to 743ppmV) and warming (ranging from +0.8°C to +6°C) both increase the GHG intensity of rice cultivation. Increased atmospheric CO2 increased GHG intensity by 31.4%, because CH4 emissions are stimulated more than rice yields. Warming increased GHG intensity by 11.8% per 1°C, largely owing to a decrease in yield. This analysis suggests that rising CO2 and warming will approximately double the GHG intensity of rice production by the end of the twenty-first century, stressing the need for management practices that optimize rice production while reducing its GHG intensity as the climate continues to change.

  10. 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.

  11. Study on Fertilizer Application and Yield Model of‘Yongyou 12’and Its Fertilization Techniques in Super-high-yielding Cultivation Single Cropping Rice%‘甬优12’施肥量与产量关系模型及超高产栽培施肥技术研究

    Institute of Scientific and Technical Information of China (English)

    蔡建军; 汪恩国; 林采舜; 何杰

    2015-01-01

    为了探明超级杂交稻‘甬优12’产量与施肥量关系,揭示其单季稻超高产栽培需肥规律,提升整体施肥技术水平,在统一栽培技术措施下测土配方施肥,跟踪调查2012—2013年12个示范方不同施肥组合及施肥量,以专家组实割实收考查产量的方法,对单季稻‘甬优12’施肥量与产量关系及超高产栽培施肥技术进行研究。结果表明,在土壤肥力水平中等的情况下,单季晚稻‘甬优12’产量(Y)随施肥量(有机肥F和N、P、K)增加而递升且呈幂次函数(近似线性)递升,其关系模型为:Y=0.00003F2-0.2963F+11302(Y=0.2301F+9258),Y=0.0504N2+24.566N+1953(Y=51.243N-1543),Y=0.0361P2+26.596P+8707(Y=34.143P+8358),Y=0.0208K2+7.4996K+8499(Y=17.793K+7306)。由此提出,11000~12000 kg/hm2目标产量为投入农家有机肥8000~12000 kg/hm2、纯N量245~265 kg/hm2、P2O5量75~105 kg/hm2、K2O量210~265 kg/hm2,N:P:K比例1.00:0.35:0.93;目标产量15000 kg/hm2为投入农家有机肥15000~20000 kg/hm2、纯N量320 kg/hm2、P2O5量190 kg/hm2、K2O量410 kg/hm2,N:P:K比例1.00:0.59:1.28。后者生产成本大幅度提高,生产风险大幅度上升,需集成超级栽培、肥料运筹、病虫防治、水桨管理等一系列协调促进,才能实现预期目标。%The relationship between fertilization level and yield of‘Yongyou 12’and the technique of fertilization for super high yield cultivation were studied in this research. Fertilization was conducted according to the soil fertile level under the unified cultivation technology. Follow up investigation was carried out of 12 demonstrations of different fertilizer combinations and the amount of fertilizer from 2012 to 2013. The rice yield was examined by the experts harvesting. Our data serve as a useful tool for elucidating the relationship between fertilization level and yield of‘Yongyou 12’and its fertilization techniques in super

  12. Current Update in Asian Rhinoplasty

    Directory of Open Access Journals (Sweden)

    Clyde H. Ishii, MD, FACS

    2014-04-01

    Full Text Available 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 Asians and whites. Due to ethnic variations, cultural differences, and occasional language barriers, careful preoperative counseling is necessary to align the patient’s expectations with the limitations of the procedure. This article will review the many facets of Asian rhinoplasty as it is practiced today.

  13. Variation in the nucleotide sequence of a prolamin gene family in wild rice.

    Science.gov (United States)

    Barbier, P; Ishihama, A

    1990-07-01

    Variation in the DNA sequence of the 10 kDa prolamin gene family within the wild rice species Oryza rufipogon was probed using the direct sequencing of PCR-amplified genes. A comparison of the nucleotide and deduced amino-acid sequences of eight Asian strains of O. rufipogon and one strain of the related African species O. longistaminata is presented.

  14. 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.

  15. Effect of Spent Mushroom Substrate on Physical and Chemical Properties and Enzymic Activity of Rice

    Institute of Scientific and Technical Information of China (English)

    Hairu YU; Xue LI; Xin ZHANG; Changming GE; Renzhe PIAO; Meishan LI; Zongjun CUI; Hongyan ZHAO

    2016-01-01

    In order to explore the substitution substrate for rice seedling on upland fields,this paper uses spent mushroom substrate to study the physical and chemical properties of substrate,enzymic activity and number of tillers during the cultivation of rice seedling on upland fields.The results show that at the three stages of rice seedling cultivation( two-leaf stage,three-leaf stage,four-leaf stage),the content of organic matter and EC in spent mushroom substrate is higher than in the control soil,p H is within the range suitable for the growth of rice,and other nutrients( total nitrogen,total phosphorus,total potassium,available nitrogen,available phosphorus) are slightly different in different periods;except phosphatase,there are significant differences in urease,catalase and sucrase between spent mushroom substrate and the control soil; the number of tillers under spent mushroom substrate is larger than under the control.

  16. Deciphering DNA methylation under heat stress in contrasting rice genotypes

    OpenAIRE

    Fradique, João Manuel Silva, 1988-

    2012-01-01

    Tese de mestrado. Biologia (Biologia Evolutiva e do Desenvolvimento). Universidade de Lisboa, Faculdade de Ciências, 2012 Rice is one of the foremost crops in the history of humanity and today it feeds billions of people worldwide, as it is the second most cultivated crop. However, rice can be affected by various environmental stresses. Global climatic models predict a gradual increase in temperature by an average of 2-4ºC by the end of this century (IPCC, 2007). Thus, future climates with...

  17. Relationships among bulk soil physicochemical, biochemical, and microbiological parameters in an organic alfalfa-rice rotation system.

    Science.gov (United States)

    Lopes, Ana R; Bello, Diana; Prieto-Fernández, Ángeles; Trasar-Cepeda, Carmen; Manaia, Célia M; Nunes, Olga C

    2015-08-01

    The microbial communities of bulk soil of rice paddy fields under an ancient organic agriculture regimen, consisting on an alfalfa-rice rotation system, were characterized. The drained soil of two adjacent paddies at different stages of the rotation was compared before rice seeding and after harvesting. The relationships among the soil microbial, physicochemical, and biochemical parameters were investigated using multivariate analyses. In the first year of rice cropping, aerobic cultivable heterotrophic populations correlated with lineages of presumably aerobic bacteria (e.g., Sphingobacteriales, Sphingomonadales). In the second year of rice cropping, the total C content correlated with presumable anaerobic bacteria (e.g., Anaerolineae). Independently of the year of rice cropping, before rice seeding, proteolytic activity correlated positively with the cultivable aerobic heterotrophic and ammonifier populations, the soil catabolic profile and with presumable aerobes (e.g., Sphingobacteriales, Rhizobiales) and anaerobes (e.g., Bacteroidales, Anaerolineae). After harvesting, strongest correlations were observed between cultivable diazotrophic populations and bacterial groups described as comprising N2 fixing members (e.g., Chloroflexi-Ellin6529, Betaproteobacteria, Alphaproteobacteria). It was demonstrated that chemical parameters and microbial functions were correlated with variations on the total bacterial community composition and structure occurring during rice cropping. A better understanding of these correlations and of their implications on soil productivity may be valid contributors for sustainable agriculture practices, based on ancient processes.

  18. 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.

  19. Subspecies specific RAPD markers in rice

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The cultivated rice (Oryza sativa L.) is known to contain two major subspecies, indica (O. sativa L. ssp. indica) and japonica (O. sativa L. ssp. japonica). The indica and japonica differentiation resulted in significance of hybrid sterility and hybrid breakdown, which are barriers of gene flow between the two major subgene pools within O. sativa. Traditional classification of indica and japonica germplasm based on isozymes. Here, we report the identification of several random amplified polymorphic DNA (RAPD) markers that have alleles specific in indica or japonica varieties and thus provide a quick and accurate tool to distinguish japonica lines from indica ones.

  20. Heart Disease and Asians and Pacific Islanders

    Science.gov (United States)

    ... Data > Minority Population Profiles > Asian American > Heart Disease Heart Disease and Asians and Pacific Islanders Overall, Asian American ... are less likely than white adults to have heart disease and they are less likely to die from ...

  1. Two Evolutionary Histories in the Genome of Rice: the Roles of Domestication Genes

    OpenAIRE

    Ziwen He; Weiwei Zhai; Haijun Wen; Tian Tang; Yu Wang; Xuemei Lu; Greenberg, Anthony J.; Hudson, Richard R; Chung-I Wu; Suhua Shi

    2011-01-01

    Genealogical patterns in different genomic regions may be different due to the joint influence of gene flow and selection. The existence of two subspecies of cultivated rice provides a unique opportunity for analyzing these effects during domestication. We chose 66 accessions from the three rice taxa (about 22 each from Oryza sativa indica, O. sativa japonica, and O. rufipogon) for whole-genome sequencing. In the search for the signature of selection, we focus on low diversity regions (LDRs) ...

  2. Visit and course at Hunan Hybrid Rice Research Ceater ( HHRRC )

    Institute of Scientific and Technical Information of China (English)

    TANZhijun

    1992-01-01

    Invited by Prof YUAN Longping 3 Japanese scientists of the delegation of National Federation of Agricultural Cooperative Association (ZEN-NOH) led by Hibino, came to visit HHRRC. During their visit, HHRRC experts introduced to them the advances in hybrid rice research in China and the Japanese guests reported the recent progresses on improvement of grain quality and cultivation techniques for indica/japonica hybrid rice.

  3. 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...

  4. Microbial Activity and Silica Degradation in Rice Straw

    Science.gov (United States)

    Kim, Esther Jin-kyung

    increased. Silicase activity did not change across nitrogen treatments despite a shift in microbial community with varied nitrogen concentration. Samples treated with different nitrogen concentrations had similar levels of diversity, however the microbial community composition differed with added nitrogen. The results demonstrated that adding nitrogen to rice straw during thermophilic decomposition nurtured a more active microbial community and promoted enzyme secretion thus improving the ability to discover enzymes for rice straw deconstruction. These results can inform future experiments for cultivating a unique, thriving compost-derived microbial community that can successfully decompose rice straw. Understanding the silicase activity of microorganisms may alleviate the challenges associated with silica in various feedstocks.

  5. Transition in nori cultivation

    DEFF Research Database (Denmark)

    Delaney, Alyne

    2011-01-01

    Consumers throughout the world have gained familiarity with the seaweed nori (porphyra spp) thanks to the popularity of Asian cuisine, particularly Japanese sushi. Few actually know much about the people who produce this seaweed, however. This article presents qualitative social science research...

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. PERTUMBUHAN DAN HASIL PANEN PADI SRI (SYSTEM OF RICE INTENSIFICATION

    Directory of Open Access Journals (Sweden)

    GEDE MENAKAADNYANA

    2012-11-01

    Full Text Available Growth and Yield of Paddy SRI (system of rice intensification. The study was conducted with the aim to conserve irrigation water use, maintaining soil health so as to support the growth of roots and the top of the rice plants become better and grain yield can be improved. The trials of SRI paddy cultivation techniques performed in the dry season planting season (MT April-May 2005 at the project site groundwater Jembrana area of 2.0 ha is in Subak Pangkung Liplip. The study results showed that the reduction in the amount of irrigation water does not interfere with plant growth, even able to increase the number of tillers per hill. The maximum number of tillers paddy SRI is 31.79 per hill, higher 79.90 % compared to Conventional paddy rice. The maximum number of tillers of Conventional paddy rice is 17,67 per hill. The grain yields of paddy SRI is 6.32 ton/ha, it is of 37.99 % higher than Conventional paddy rice. The grain yield of Conventional paddy rice is 4.58 ton/ha. Based on the results of field trials, can be recommended for further trials with measuring irrigation water.

  14. The Asian Newspaper's Reluctant Revolution.

    Science.gov (United States)

    Lent, John A., Ed.

    This book is composed of 19 articles written by both Asian and American scholars on the history and present conditions of newspapers in 15 Asian nations: China, Hong Kong, Japan, Korea, Taiwan, Australia, Burma, Indonesia, Malaysia and Singapore, the Philippines, Thailand, South Vietnam, Ceylon, India, and Pakistan. Two overviews of the Asian…

  15. 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...

  16. 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.

  17. 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.

  18. [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.

  19. 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.

  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. 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.

  2. Estimating Rice Yield under Changing Weather Conditions in Kenya Using CERES Rice Model

    Directory of Open Access Journals (Sweden)

    W. O. Nyang’au

    2014-01-01

    Full Text Available Effects of change in weather conditions on the yields of Basmati 370 and IR 2793-80-1 cultivated under System of Rice Intensification (SRI in Mwea and Western Kenya irrigation schemes were assessed through sensitivity analysis using the Ceres rice model v 4.5 of the DSSAT modeling system. Genetic coefficients were determined using 2010 experimental data. The model was validated using rice growth and development data during the 2011 cropping season. Two SRI farmers were selected randomly from each irrigation scheme and their farms were used as research fields. Daily maximum and minimum temperatures and precipitation were collected from the weather station in each of the irrigation schemes while daily solar radiation was generated using weatherman in the DSSAT shell. The study revealed that increase in both maximum and minimum temperatures affects Basmati 370 and IR 2793-80-1 grain yield under SRI. Increase in atmospheric CO2 concentration led to an increase in grain yield for both Basmati and IR 2793-80-1 under SRI and increase in solar radiation also had an increasing impact on both Basmati 370 and IR 2793-80-1 grain yield. The results of the study therefore show that weather conditions in Kenya affect rice yield under SRI and should be taken into consideration to improve food security.

  3. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-03-01

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

  5. 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.

  6. Rice (Oryza) hemoglobins

    Science.gov (United States)

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

  7. 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.

  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

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Y.; Wu, S.C.; Yu, X.Z. [Croucher Institute for Environmental Sciences and Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong); Wong, M.H., E-mail: mhwong@hkbu.edu.h [Croucher Institute for Environmental Sciences and Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong); Institute of Urban Environment, Chinese Academy of Sciences, Xiamen (China)

    2010-08-15

    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. 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.

  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. Resistance Evaluation of Some Hybrid Rice, Conventional Early Indica and Late Japonica Rice to Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    SHEN Ying; Adreit Henry; ZHU Xu-dong; Milazzo Joelle; CHEN Hong-qi; Tharreau Didier

    2003-01-01

    Thirty isolates of Magnaporthe grisea collected from 18 provinces/cities representing 21 pathotypes and 9 different lineages were inoculated to rice varieties with known resistance genes and some hybrid rices,conventional early indica and late japonica varieties cultivated recently in China.Virulence spectrum of the 30 isolates was very different,showing that they recognize numerous different resistance genes.Varieties also revealed very different resistance patterns showing that they carry different resistance genes or combinations of resistance genes.On the basis of comparisons with international differential varieties with known resistance genes,resistance genes in certain Chinese varieties could be speculated.The results indicated that some of them were resistant to most of the isolates tested and that they could be of interest as resistance sources for hybrid parents or to be planted in the field directly.

  13. Adapting rice anther culture to gene transformation and RNA interference

    Institute of Scientific and Technical Information of China (English)

    CHEN Caiyan; XIAO Han; ZHANG Wenli; WANG Aiju; XIA Zhihui; LI Xiaobing; ZHAI Wenxue; CHENG Zhukuan; ZHU Lihuang

    2006-01-01

    Anther culture offers a rapid method of generating homozygous lines for breeding program and genetic analysis. To produce homozygous transgenic lines of rice (Oryza sativa L.) in one step, we developed an efficient protocol of anther-callus-based transformation mediated by Agrobacterium after optimizing several factors influencing efficient transformation, including callus induction and Agrobacterium density for co-cultivation. Using this protocol, we obtained 145 independent green transformants from five cultivars of japonica rice by transformation with a binary vector pCXK1301 bearing the rice gene, Xa21 for resistance to bacterial blight, of which 140 were further confirmed by PCR and Southern hybridization analysis, including haploids (32.1%), diploids (62.1%)and mixoploids (7.5%). Fifteen diploids were found to be doubled haploids, which accounted for 10.7% of the total positive lines. Finally, by including 28 from colchicine induced or spontaneous diploidization of haploids later after transformation, a total of 43 doubled haploids (30.7%) of Xa21transgenic lines were obtained. We also generated two RNAi transgenic haploids of the rice OsMADS2 gene, a putative redundant gene of OsMADS4 based on their sequence similarity, to investigate its possible roles in rice flower development by this method. Flowers from the two OsMADS2RNAi transgenic haploids displayed obvious homeotic alternations, in which lodicules were transformed into palea/lemma-like tissues, whereas identities of other floral organs were maintained. The phenotypic alternations were proved to result from specific transcriptional suppression of OsMADS2gene by the introduced RNAi transgene. The results confirmed that OsMADS2 is involved in lodicule development of rice flower and functionally redundant with OsMADS4 gene. Our results demonstrated that rice anther culture could be adapted to gene transformation and RNAi analysis in rice.

  14. Transgenic strategies to confer resistance against viruses in rice plants

    Directory of Open Access Journals (Sweden)

    Takahide eSasaya

    2014-01-01

    Full Text Available Rice (Oryza sativa L. is cultivated in more than 100 countries and supports nearly half of the world’s population. Developing efficient methods to control rice viruses is thus an urgent necessity because viruses cause serious losses in rice yield. Most rice viruses are transmitted by insect vectors, notably planthoppers and leafhoppers. Viruliferous insect vectors can disperse their viruses over relatively long distances, and eradication of the viruses is very difficult once they become widespread. Exploitation of natural genetic sources of resistance is one of the most effective approaches to protect crops from virus infection; however, only a few naturally occurring rice genes confer resistance against rice viruses. In an effort to improve control, many investigators are using genetic engineering of rice plants as a potential strategy to control viral diseases. Using viral genes to confer pathogen-derived resistance against crops is a well-established procedure, and the expression of various viral gene products has proved to be effective in preventing or reducing infection by various plant viruses since the 1990s. RNA-interference (RNAi, also known as RNA silencing, is one of the most efficient methods to confer resistance against plant viruses on their respective crops. In this article, we review the recent progress, mainly conducted by our research group, in transgenic strategies to confer resistance against tenuiviruses and reoviruses in rice plants. Our findings also illustrate that not all RNAi constructs against viral RNAs are equally effective in preventing virus infection and that it is important to identify the viral Achilles’ heel gene to target for RNAi attack when engineering plants.

  15. 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.

  16. 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.

  17. Fighting Asian soybean rust

    Directory of Open Access Journals (Sweden)

    Caspar eLangenbach

    2016-06-01

    Full Text Available Phakopsora pachyrhizi is a biotrophic fungus provoking Asian soybean rust (SBR disease. SBR poses a major threat to global soybean production. Though several resistance genes provided soybean immunity to certain P. pachyrhizi races, the pathogen swiftly overcame this resistance. Therefore, fungicides are the only current means to control SBR. However, insensitivity to fungicides is soaring in P. pachyrhizi and, therefore, alternative measures are needed for SBR control. In this article, we discuss the different approaches for fighting SBR and their potential, disadvantages, and advantages over other measures. These encompass conventional breeding for SBR resistance, transgenic approaches, exploitation of transcription factors, secondary metabolites, and antimicrobial peptides, RNAi/HIGS, and biocontrol strategies. It seems that an integrating approach exploiting different measures is likely to provide the best possible means for the effective control of SBR.

  18. 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.

  19. Describing and measuring Ethnoentomological Knowledge of Rice Pests: Tradition and Change among Asian Rice Farmers

    NARCIS (Netherlands)

    Price, L.L.; Björnsen Gurung, A.

    2006-01-01

    The paper presents a methodology that guided several ethnoentomological research projects and goes on to examine and compare the results from two independent research locations in Asia. The first location is in the Philippines, a Green Revolution area that has been heavily impacted by extension mess

  20. 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…

  1. 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.

  2. Osteoporosis and Asian American Women

    Science.gov (United States)

    ... not supported by your browser. Home Osteoporosis Women Osteoporosis and Asian American Women Publication available in: PDF ( ... Are Available? Resources For Your Information What Is Osteoporosis? Osteoporosis is a condition in which the bones ...

  3. [Comprehensive evaluation of improving effects of different organic wastes on a newly reclaimed cultivated land].

    Science.gov (United States)

    Xu, Qiu-tong; Kong, Zhang-liang; Zhang, Ming-kui

    2016-02-01

    There are many problems such as low soil organic matter, available nutrients and microbial activity, compaction, and poor tillage properties for a newly reclaimed cultivated land, and the establishment of a fast, effective measure for improving soil fertility quality is of importance to enhance the quality and production performance of the newly cultivated land. A field experiment was carried out to observe the effect of organic wastes on soil fertility of a newly reclaimed cultivated land, and compared the differences of different types of urban organic wastes. The field experiment included nine treatments, i.e., pig manure, chicken manure, rice straw, vegetable harvest residue, urban sludge, biogas residue, manure+rice straw compost, garbage compost and control without organic fertilizer at annual application rate of 30 t . hm-2, and ran for three consecutive years. The results showed that the application of each type of the eight organic wastes had obvious effects on improving soil fertility. Among them, pig manure, chicken manure, pig manure+rice straw compost, rice straw and biogas residue were the most effective to enhance the carbon pool management index of soil. The addition of pig manure+rice straw compost and biogas residue had the best effect on increasing the soil water stable aggregates and decreasing soil bulk density. Sewage sludge, pig manure+rice straw compost and garbage compost could enhance soil water holding capacity. Pig manure, chicken manure and pig manure+rice straw compost had most obvious effect on increasing soil available nutrients. All kinds of organic wastes increased the number of soil microorganisms and the activity of enzymes. There were some risk of soil heavy metals pollution.for the long-term application of sludge, garbage compost and manure. However, the impact of short-term application of the wastes on soil environmental quality was not obvious. Overall, effects of organic wastes on soil fertility decreased in the order of pig

  4. 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.

  5. [Dendrobium officinale stereoscopic cultivation method].

    Science.gov (United States)

    Si, Jin-Ping; Dong, Hong-Xiu; Liao, Xin-Yan; Zhu, Yu-Qiu; Li, Hui

    2014-12-01

    The study is aimed to make the most of available space of Dendrobium officinale cultivation facility, reveal the yield and functional components variation of stereoscopic cultivated D. officinale, and improve quality, yield and efficiency. The agronomic traits and yield variation of stereoscopic cultivated D. officinale were studied by operating field experiment. The content of polysaccharide and extractum were determined by using phenol-sulfuric acid method and 2010 edition of "Chinese Pharmacopoeia" Appendix X A. The results showed that the land utilization of stereoscopic cultivated D. officinale increased 2.74 times, the stems, leaves and their total fresh or dry weight in unit area of stereoscopic cultivated D. officinale were all heavier than those of the ground cultivated ones. There was no significant difference in polysaccharide content between stereoscopic cultivation and ground cultivation. But the extractum content and total content of polysaccharide and extractum were significantly higher than those of the ground cultivated ones. In additional, the polysaccharide content and total content of polysaccharide and extractum from the top two levels of stereoscopic culture matrix were significantly higher than that of the ones from the other levels and ground cultivation. Steroscopic cultivation can effectively improves the utilization of space and yield, while the total content of polysaccharides and extractum were significantly higher than that of the ground cultivated ones. The significant difference in Dendrobium polysaccharides among the plants from different height of stereo- scopic culture matrix may be associated with light factor.

  6. 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.

  7. Cultivation of oyster mushroom (Pleurotus ostreatus on oil palm residues

    Directory of Open Access Journals (Sweden)

    Tongwised, A.

    2001-11-01

    Full Text Available This study is aimed to use oil palm residues to cultivate the oyster mushroom, Pleurotus ostreatus, which is one of the most important mushrooms cultivated worldwide. Spawn was prepared on sorghum seeds and inoculated on substrate in plastic bags. Oil palm fronds were cut and used to grow Pleurotus ostreatus. The first fructification occurred 20 days after waterring. The biological efficiency reached at 28.6%. When sawdust of para rubber logs was added to the cut oil palm fronds at the rate of 1:1 (vol : vol., the biological efficiency reached at 39.3%.Supplementary material at the rate of 5% was also added into the combination of cut oil palm frond and sawdust. The result showed that rice bran, corn meal or oil palm-kernel meal give yields between 142.2-165.0 g/bag (B.E. = 42.8-49.6, which were not statistically different. Oil palm pericarp waste was also used as main substrate for P. ostreatus cultivation. The average yield obtained during 40 days havesting period was 112.6 g/bag (B.E. = 64.3%. Addition of sawdust or rice bran into pericarp waste decreased the yield of the basidiocarps. Palm-kernel meal at the rate of 5-20% was used as a supplement material. Addition of 20% palmkernel meal into sawdust supported higher yield. The biological efficiency reached 55.8%. From the above results, four formulae of the substrate were prepared. Treatment of oil palm pericarp waste + 3% rice bran + 3% corn meal + 0.75% Ca(OH2 supported higher yield of the basidiocarps. The average yield obtained from 950 g of substrate was 190.2 g during 60 days havesting (B.E. = 57.2%. Using 6% palm-kernel substitute 3% rice bran + 3% corn meal supported the same yield (B.E. = 56.2% Using sawdust as the main substrate, the yield achieved was less than that obtained with oil palm pericarp waste. The average yield from treatment of sawdust + 3% rice bran + 3% corn meal + 0.75% Ca (OH2 was 154.0 g/bag (B.E. = 46.3% while treatment of sawdust + 6% palm-kernel meal + 0

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. Bioconversion of rice straw into a soil-like substrate

    Science.gov (United States)

    Yu, Chengying; Liu, Hong; Xing, Yidong; Manukovsky, N. S.; Kovalev, V. S.; Gurevich, Yu. L.

    To increase the closure of bioregenerative life support systems (BLSS), the bioconversion of rice straw into a soil-like substrate (SLS) by mushrooms and worms has been studied. The results showed that rice straw could be treated better by aerobic fermentation and succeeding growth of mushrooms Pleurotus ostreatus. In this process the total content of lignocellulose in the straw was removed by 37.74%. Furthermore, 46.68 g (fresh weight) of mushrooms could be produced from 100.0 g (dry weight) of rice straw. During the conversion of rice straw into a starting SLS by mushrooms and worms, the matter loss was 77.31%. The lettuce has been planted in the SLS and the yield when lettuce was cultivated on the SLS (8.77gm-2day-1) was comparable to the yield obtained on the nutrient solution. In addition, the silicon in the SLS ash can reach upto 32% and the circulation of it is expected during the growth of rice.

  16. Rice: The Little Grain That Feeds the World. Young Discovery Library No. 30.

    Science.gov (United States)

    Brice, Raphaelle

    Part of an international series of amply illustrated, colorful, small-sized books for children ages 5 to 10, this volume is designed to enhance learning and serve as an educational resource. The historical and modern cultivation of rice around the world and its importance as food and for other uses are explored. Answers to such questions as why is…

  17. Gas transport through the root-shoot transition zone of rice tillers

    NARCIS (Netherlands)

    Groot, T.T.; Bodegom, van P.M.; Meijer, H.A.J.; Harren, F.J.M.

    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

  18. Rape: an Asian perspective.

    Science.gov (United States)

    Nadesan, K

    2001-06-01

    Rape is one of the fastest growing violent crimes in many parts of the world. Rape laws have been amended in most countries in an attempt to cope with the proliferation of this crime. Even though the legal definition of rape and the procedural laws have been amended, rape remains a serious problem in both the developed and developing nations. In some countries the offence of rape carries severe punishment sometimes even the death sentence. In many jurisdictions the term 'sexual penetration' is being used instead of 'sexual intercourse'. Sexual penetration includes sexual intercourse, anal intercourse, cunnilingus, fellatio or any other intrusions involving any part of a human body or of any object into the genital or anal opening of a person's body. In many countries rape and other sexual offences have been replaced with a series of gender neutral and graded offences with appropriate punishments. Medical examination can provide independent, scientific, corroborative evidence that may be of value to the court in arriving at a judgement. Doctors should have a clear understanding of different rape laws in order to apprectiate the various issues involved. Special knowledge, skill and experience are essential to conduct a good-quality medical examination. There is a dearth of trained forensic physicians in many Asian countries. However, managing a rape victim (survivor) goes for beyond proving the case in a court of law. There should be an adequate rehabilitation programme available to the victims to help them cope.

  19. 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

  20. 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.

  1. Cultivation of Marine Sponges.

    Science.gov (United States)

    Osinga; Tramper; Wijffels

    1999-11-01

    There is increasing interest in biotechnological production of marine sponge biomass owing to the discovery of many commercially important secondary metabolites in this group of animals. In this article, different approaches to producing sponge biomass are reviewed, and several factors that possibly influence culture success are evaluated. In situ sponge aquacultures, based on old methods for producing commercial bath sponges, are still the easiest and least expensive way to obtain sponge biomass in bulk. However, success of cultivation with this method strongly depends on the unpredictable and often suboptimal natural environment. Hence, a better-defined production system would be desirable. Some progress has been made with culturing sponges in semicontrolled systems, but these still use unfiltered natural seawater. Cultivation of sponges under completely controlled conditions has remained a problem. When designing an in vitro cultivation method, it is important to determine both qualitatively and quantitatively the nutritional demands of the species that is to be cultured. An adequate supply of food seems to be the key to successful sponge culture. Recently, some progress has been made with sponge cell cultures. The advantage of cell cultures is that they are completely controlled and can easily be manipulated for optimal production of the target metabolites. However, this technique is still in its infancy: a continuous cell line has yet to be established. Axenic cultures of sponge aggregates (primmorphs) may provide an alternative to cell culture. Some sponge metabolites are, in fact, produced by endosymbiotic bacteria or algae that live in the sponge tissue. Only a few of these endosymbionts have been cultivated so far. The biotechnology for the production of sponge metabolites needs further development. Research efforts should be continued to enable commercial exploitation of this valuable natural resource in the near future.

  2. Diversity and selective sweep in the OsAMT1;1 genomic region of rice

    Directory of Open Access Journals (Sweden)

    Chen Sheng

    2011-03-01

    Full Text Available Abstract Background Ammonium is one of the major forms in which nitrogen is available for plant growth. OsAMT1;1 is a high-affinity ammonium transporter in rice (Oryza sativa L., responsible for ammonium uptake at low nitrogen concentration. The expression pattern of the gene has been reported. However, variations in its nucleotides and the evolutionary pathway of its descent from wild progenitors are yet to be elucidated. In this study, nucleotide diversity of the gene OsAMT1;1 and the diversity pattern of seven gene fragments spanning a genomic region approximately 150 kb long surrounding the gene were surveyed by sequencing a panel of 216 rice accessions including both cultivated rice and wild relatives. Results Nucleotide polymorphism (Pi of OsAMT1;1 was as low as 0.00004 in cultivated rice (Oryza sativa, only 2.3% of that in the common wild rice (O. rufipogon. A single dominant haplotype was fixed at the locus in O. sativa. The test values for neutrality were significantly negative in the entire region stretching 5' upstream and 3' downstream of the gene in all accessions. The value of linkage disequilibrium remained high across a 100 kb genomic region around OsAMT1;1 in O. sativa, but fell rapidly in O. rufipogon on either side of the promoter of OsAMT1;1, demonstrating a strong natural selection within or nearby the ammonium transporter. Conclusions The severe reduction in nucleotide variation at OsAMT1;1 in rice was caused by a selective sweep around OsAMT1;1, which may reflect the nitrogen uptake system under strong selection by the paddy soil during the domestication of rice. Purifying selection also occurred before the wild rice diverged into its two subspecies, namely indica and japonica. These findings would provide useful insights into the processes of evolution and domestication of nitrogen uptake genes in rice.

  3. 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:

  4. 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.

  5. South Asian High and Asian-Pacific-American Climate Teleconnection

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Growing evidence indicates that the Asian monsoon plays an important role in affecting the weather and climate outside of Asia. However, this active role of the monsoon has not been demonstrated as thoroughly as has the variability of the monsoon caused by various impacting factors such as sea surface temperature and land surface. This study investigates the relationship between the Asian monsoon and the climate anomalies in the Asian-Pacific-American (APA) sector. A hypothesis is tested that the variability of the upper-tropospheric South Asian high (SAH), which is closely associated with the overall heating of the large-scale Asian monsoon, is linked to changes in the subtropical western Pacific high (SWPH), the midPacific trough, and the Mexican high. The changes in these circulation systems cause variability in surface temperature and precipitation in the APA region. A stronger SAH is accompanied by a stronger and more extensive SWPH. The enlargement of the SWPH weakens the mid-Pacific trough. As a result, the southern portion of the Mexican high becomes stronger. These changes are associated with changes in atmospheric teleconnections, precipitation, and surface temperature throughout the APA region. When the SAH is stronger, precipitation increases in southern Asia, decreases over the Pacific Ocean, and increases over the Central America. Precipitation also increases over Australia and central Africa and decreases in the Mediterranean region. While the signals in surface temperature are weak over the tropical land portion,they are apparent in the mid latitudes and over the eastern Pacific Ocean.

  6. 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.

  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. Role of silicon in alleviation of iron deficiency and toxicity in hydroponically-grown rice (Oryza sativa L.) plants

    OpenAIRE

    A Abdol Zadeh; z Kiani Chalmardi

    2013-01-01

    Silicon (Si) nutrition may alleviate biotic and abiotic stresses including heavy metal deficiency and toxicity in plants. Iron deficiency and toxicity are important limiting factors in growth of rice. In the present study, role of Si nutrition on alleviation of iron deficiency and toxicity was investigated in rice plants. Plants were cultivated in greenhouse in hydroponics, using Yoshida solution, under different iron treatments (0, 2, 10, 20, 50, 100 and 250 mg/L as Fe- EDTA) and Si nutritio...

  9. Future atmospheric conditions increase the greenhouse gas intensity of rice production

    Science.gov (United States)

    Van Groenigen, K.; Van Kessel, C.; Hungate, B. A.

    2012-12-01

    Elevated levels of atmospheric CO2 and rising temperatures are both expected to alter rice yields and greenhouse gas (GHG) emissions from rice paddies. This is important, because rice cultivation is one of the largest anthropogenic sources of the potent GHG methane (CH4) and rice is the world's second-most produced staple crop. Because global food demand is growing, it makes sense to assess GHG emissions from croplands on the basis of yield rather than land area, so that efforts to reduce GHG emissions occur with taking into consideration the effects on food production. However, it is unclear whether or how the GHG intensity (that is, yield-scaled GHG emissions) of cropping systems will be affected by future atmospheric conditions. Using meta-analysis, we show that elevated atmospheric CO2 (ranging from 550 to 743 ppmV) and warming (ranging from +0.8°C to +6°C) both increase the GHG intensity of rice cultivation. Elevated atmospheric CO2 increased GHG intensity by 31.4%, because CH4 emissions are stimulated more than rice yields. Warming increased GHG intensity by 11.8% per 1°C, largely due to a decrease in yield. Our findings underscore the need for mitigation and adaptation efforts to secure global food supply while at the same time keeping GHG emissions in check.

  10. Mechanisms of Enhanced Rice Growth and Nitrogen Uptake by Nitrate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Rice is being increasingly cultivated in intermittently irrigated regions and also in aerobic soil in which Nitrate (NO3-)plays important role in nutrition of plant. However, there is no information regarding the influence of nitrate on the overall growth and uptake of nitrogen (N) in rice plant. Solution culture experiments were carried out to study the effects of NO3-on the plant growth, uptake of N, and uptake kinetics of NH4+ in four typical rice (Oryza sativa L.) cultivars (conventional indica, conventional japonica, hybrid indica, and hybrid japonica), and on plasma membrane potential in roots of two conventional rice cultivars (indica and japonica) at the seedling stage. The results obtained indicated that a ratio of 50/50 NH4+-N/NO3--N increased the average biomass of rice shoots and roots by 20% when compared with that of 100/0NH4+-N/NO3--N. In case of the 50/50 ratio, as compared with the 100/0 ratio, total N accumulated in shoots and roots of rice increased on an average by 42% and 57%, respectively. Conventional indica responds to NO3- more than any other cultivars that were tested. The NO3- supply increased the maximum uptake rate (Vmax) of NH4+ by rice but did not show any effect on the apparent Michaelis-Menten constant (Km) value, with the average value of Vmax for NH4+ among the four cultivars being increased by 31.5% in comparison with those in the absence of NO3-. This suggested that NO3-significantly increased the numbers of the ammonium transporters. However, the lack of effect on the Km value also suggested that the presence of NO3- had no effect on the affinity of the transporters for NH4+. The plasma membrane potential in the roots of conventional indica and japonica were greatly increased by the addition of NO3-, suggesting that NO3- could improve the uptake of N by roots of the rice plant. In conclusion, the mechanisms by which NO3- enhances the growth and N uptake of rice plant was found by the increased value of Vmax of NH4+ and

  11. Classification of Broken Rice Kernels using 12D Features

    Directory of Open Access Journals (Sweden)

    SUNDER ALI KHOWAJA

    2016-07-01

    Full Text Available Integrating the technological aspect for assessment of rice quality is very much needed for the Asian markets where rice is one of the major exports. Methods based on image analysis has been proposed for automated quality assessment by taking into account some of the textural features. These features are good at classifying when rice grains are scanned in controlled environment but it is not suitable for practical implementation. Rice grains are placed randomly on the scanner which neither maintains the uniformity in intensity regions nor the placement strategy is kept ideal thus resulting in false classification of grains. The aim of this research is to propose a method for extracting set of features which can overcome the said issues. This paper uses morphological features along-with gray level and Hough transform based features to overcome the false classification in the existing methods. RBF (Radial Basis function is used as a classification mechanism to classify between complete grains and broken grains. Furthermore the broken grains are classified into two classes? i.e. acceptable grains and non-acceptable grains. This research also uses image enhancement technique prior to the feature extraction and classification process based on top-hat transformation. The proposed method has been simulated in MATLAB to visually analyze and validate the results.

  12. 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.

  13. 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.

  14. Rheological properties of rice-blackgram batter while replacing white rice with brown rice.

    Science.gov (United States)

    Manickavasagan, Annamalai; Al-Marhubi, Insaaf Mohd; Dev, Satyanarayan

    2014-06-01

    Rice-blackgram batter is a raw material for many traditional convenience foods in Asia. Reformulation of traditional convenience food by replacing white rice with whole rice (brown rice) is a novel method to reduce the consumption of refined grain and increase the intake of whole grain in our diet. In this study, rheological properties of rice-blackgram batter was investigated while replacing white rice with brown rice at five levels (T1--0% replacement (control), T2--25% replacement, T3--50% replacement, T4--75% replacement, and T5--100% replacement). The shear stress versus shear rate plot indicates that the rice-blackgram batter exhibited non-Newtonian fluid behavior (shear thinning property) even after 100% replacement of white rice with brown rice. The rheological characteristics of rice-blackgram batters fitted reasonably well in Cassan (r2 = 0.8521-0.9856) and power law (r2 = 0.8042-0.9823) models. Brown rice replacement at all levels did not affect the flow behavior index, yield stress, consistency coefficient, and apparent viscosity of batter at 25 degrees C. However, at higher temperature, the viscosity was greater for T4 and T5 (no difference between them) than T1, T2, and T3 (no difference between them) batters. Further research is required to determine the sensory attributes and acceptability of the cooked products with brown rice-blended batter.

  15. 稻鸭共育对病虫草害及经济效益的影响%Effects of Rice-duck Mutualism on Diseases Insect Pests and Weeds and Economic Benefits

    Institute of Scientific and Technical Information of China (English)

    邓强辉; 潘晓华

    2008-01-01

    [Objective]Study on the effects of rice-duck mutualism on weeds and insects pests and economic benefits of paddy field.[Method]Comparison of the incidence of weeds,sheath blight and insects pest under rice-duck mutualism,conventional cultivation and control treatment,the yield and economic benefits were analyzed under the 3 treatments.[Result]Average occurrence of weeds in rice-duck mutualism group decreased by 2.33 and 52.08 ind/m2 compared with that in conventional cultivation and control treatment;the control rate of mutualism was up to 75% against rice hopper,but just between 25%-60% against rice leaf miler and Chilo suppressalis.The rates of diseased plant and diseased holl against rice sheath blight were higher and disease indices were lower compared with control group.The yield of mutualism group was identical with conventional cultivation,which was greatly higher than that of control group.The results suggested an higher economic benefits and lower cost benefit ratio for rice-duck mutualism treatment.[Conclusion]Rice-duck mutualism gives birth to a positive effect to control the diseases,insect pests and weeds,as well as to economic benefits,providing basis on extension of rice-duck mutualism system.

  16. Discrimination rice cropping systems using multi-temporal Proba-V data in the Mekong Delta, Vietnam

    Science.gov (United States)

    Son, Nguyen-Thanh; Chen, Chi-Farn; Chen, Cheng-Ru; Chang, Ly-Yu; Chiang, Shou-Hao; Lau, Khin-Va

    2016-04-01

    Rice is considered a main source of livelihoods for several billions of people worldwide and plays an important role in the economy of many Asian countries. More than just a food source, rice production is regarded as one of the most important components to maintaining political stability and is also a national subject of economic policy due to domestic food consumption and grain exports. Vietnam is globally one of the largest rice producers and suppliers with more than 80% of the exported rice amount produced from the Mekong River Delta. This delta is one of the three deltas in the world most vulnerable to the climate change, causing the potential loss of rice yields. Thus, spatiotemporal information of rice cropping systems is important for agricultural management to ensure food security and rice grain exports. Coarse resolution satellite data such as MODIS demonstrates the applicability for rice mapping at a large scale. However, the use of MODIS data for such a monitoring purpose still reveals a challenging task due to mixed-pixel issues. The Proba-V satellite launched on 7 May 2013 is a potential candidate for this monitoring purpose because the data include four spectral bands (blue, red, near-infrared and mid-infrared) with a swath of 2,285 km with a spatial resolution of 100 m and temporal resolution of 5 days. This study aimed to investigate the applicability of multi-temporal Proba-V data for mapping rice cropping systems in Mekong Delta River, South Vietnam. The data were processed for 2014-2015 rice cropping seasons, following three main steps: (1) construction of smooth time-series NDVI data, (2) classification of rice cropping systems using crop phenological metrics, and (3) accuracy assessment of the mapping results. The results indicated that the smooth time-series NDVI profiles characterized the temporal spectral responses of rice fields through different growing stages of rice plant, which was critically important for understanding rice crop

  17. Soil erosion from shifting cultivation and other smallholder land use in Sarawak, Malaysia

    DEFF Research Database (Denmark)

    Neergaard, Andreas de; Magid, Jakob; Mertz, Ole

    2008-01-01

    derived from nuclear fallout, and was used to estimate the retention of topsoil in the profiles. Soil chemical parameters in upland rice fields, such as extractable cations, pH and conductivity, indicated limited soil transportation downslope, and depletion of cations from upslope samples are most likely......The sustainability of shifting cultivation systems and their impact on soil quality continues to be debated, and although a growing body of literature shows a limited impact on, e.g. soil carbon stocks, shifting cultivation still has a reputation as detrimental to the environment. We wished...

  18. Phylogenetic relationships of annual and perennial wild rice: probing by direct DNA sequencing.

    Science.gov (United States)

    Barbier, P; Morishima, H; Ishihama, A

    1991-05-01

    The phylogenetic relationships between Asian wild rice strains were analyzed by direct sequencing of PCR-amplified DNA fragments. The sequence of three introns located in the phytochrome gene was determined for eight strains of the Asian wild rice, Oryza rufipogon, and one strain of the related African species, Oryza longistaminata. The number of nucleotide substitutions per site between various strains within a single species, O. rufipogon, ranged between 0.0017 and 0.0050, while those between two related species, O. rufipogon and O. longistaminate, were 0.043-0.049 (23-26 within 532 bp). Taken together with the sequence differences of the 10-kDa prolamin gene, a model is proposed for the phylogenetic relationships and evolutionary history of annuals and perennials within O. rufipogon.

  19. MediterrAsian Diet Products That Could Raise HDL-Cholesterol: A Systematic Review

    Science.gov (United States)

    Giacosa, Attilio; Morazzoni, Paolo; Guido, Davide; Grassi, Mario; Morandi, Gabriella; Bologna, Chiara; Allegrini, Pietro

    2016-01-01

    Background. High HDL-cholesterol (HDL-C) values are negatively correlated with cardiovascular diseases. This review analyses the effect of the supplementation with various Mediterranean diet products (artichoke, bergamot, and olive oil) and Asian diet products (red yeast rice) on the HDL-C value in dyslipidemic subjects. Methods. A systematic review has been done involving all the English written studies published from the 1st of January 1958 to the 31st of March 2016. Results. The results of this systematic review indicate that the dietary supplementation with red yeast rice, bergamot, artichoke, and virgin olive oil has promising effects on the increase of HDL-C serum levels. The artichoke leaf extract and virgin olive oil appear to be particularly interesting, while bergamot extract needs further research and the effect of red yeast rice seems to be limited to patients with previous myocardial infarction. Conclusions. Various MediterrAsian diet products or natural extracts may represent a potential intervention treatment to raise HDL-C in dyslipidemic subjects. PMID:27882320

  20. MediterrAsian Diet Products That Could Raise HDL-Cholesterol: A Systematic Review.

    Science.gov (United States)

    Rondanelli, Mariangela; Giacosa, Attilio; Morazzoni, Paolo; Guido, Davide; Grassi, Mario; Morandi, Gabriella; Bologna, Chiara; Riva, Antonella; Allegrini, Pietro; Perna, Simone

    2016-01-01

    Background. High HDL-cholesterol (HDL-C) values are negatively correlated with cardiovascular diseases. This review analyses the effect of the supplementation with various Mediterranean diet products (artichoke, bergamot, and olive oil) and Asian diet products (red yeast rice) on the HDL-C value in dyslipidemic subjects. Methods. A systematic review has been done involving all the English written studies published from the 1st of January 1958 to the 31st of March 2016. Results. The results of this systematic review indicate that the dietary supplementation with red yeast rice, bergamot, artichoke, and virgin olive oil has promising effects on the increase of HDL-C serum levels. The artichoke leaf extract and virgin olive oil appear to be particularly interesting, while bergamot extract needs further research and the effect of red yeast rice seems to be limited to patients with previous myocardial infarction. Conclusions. Various MediterrAsian diet products or natural extracts may represent a potential intervention treatment to raise HDL-C in dyslipidemic subjects.

  1. MediterrAsian Diet Products That Could Raise HDL-Cholesterol: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Mariangela Rondanelli

    2016-01-01

    Full Text Available Background. High HDL-cholesterol (HDL-C values are negatively correlated with cardiovascular diseases. This review analyses the effect of the supplementation with various Mediterranean diet products (artichoke, bergamot, and olive oil and Asian diet products (red yeast rice on the HDL-C value in dyslipidemic subjects. Methods. A systematic review has been done involving all the English written studies published from the 1st of January 1958 to the 31st of March 2016. Results. The results of this systematic review indicate that the dietary supplementation with red yeast rice, bergamot, artichoke, and virgin olive oil has promising effects on the increase of HDL-C serum levels. The artichoke leaf extract and virgin olive oil appear to be particularly interesting, while bergamot extract needs further research and the effect of red yeast rice seems to be limited to patients with previous myocardial infarction. Conclusions. Various MediterrAsian diet products or natural extracts may represent a potential intervention treatment to raise HDL-C in dyslipidemic subjects.

  2. Diabetic nephropathy in Surinamese South Asian subjects

    OpenAIRE

    Chandieshaw, Prataap Kalap; Chandie Shaw, Prataap Kalap

    2008-01-01

    This thesis focuses on the incidence and risk factors for nephropathy in diabetic and non-diabetic Surinamese South Asians. The Surinamese South Asians, originally descended from the North-East India. Due to the former colonial bounds with the Netherlands, a relatively young South Asian migrant population settled in the Netherlands. South Asians have a high prevalence of central obesity and an eight-fold higher prevalence for type 2 diabetes mellitus. We found the following conclusions: 1.Sur...

  3. Development of Commercial Thermo-sensitive Genic Male Sterile Rice Accelerates Hybrid Rice Breeding Using the CRISPR/Cas9-mediated TMS5 Editing System

    OpenAIRE

    2016-01-01

    Hybrid rice breeding offers an important strategy to improve rice production, in which the cultivation of a male sterile line is the key to the success of cross-breeding. CRISPR/Cas9 systems have been widely used in target-site genome editing, whereas their application for crop genetic improvement has been rarely reported. Here, using the CRISPR/Cas9 system, we induced specific mutations in TMS5, which is the most widely applied thermo-sensitive genic male sterility (TGMS) gene in China, and ...

  4. QTL map meets population genomics: an application to rice.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Fawcett

    Full Text Available Genes involved in the transition from wild to cultivated crop species should be of great agronomic importance. Population genomic approaches utilizing genome resequencing data have been recently applied for this purpose, although it only reports a large list of candidate genes with no biological information. Here, by resequencing more than 30 genomes altogether of wild rice Oryza rufipogon and cultivated rice O. sativa, we identified a number of regions with clear footprints of selection during the domestication process. We then focused on identifying candidate domestication genes in these regions by utilizing the wealth of QTL information in rice. We were able to identify a number of interesting candidates such as transcription factors that should control key domestication traits such as shattering, awn length, and seed dormancy. Other candidates include those that might have been related to the improvement of grain quality and those that might have been involved in the local adaptation to dry conditions and colder environments. Our study shows that population genomic approaches and QTL mapping information can be used together to identify genes that might be of agronomic importance.

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

    Science.gov (United States)

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

    2015-04-01

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

  6. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    APJTB MonthlyAims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)is administrated by Hainan Medical University and sponsored by Asian Pacific Tropical Medicine Press,and aims to establish an international academic communicating platform for researchers of tropical biomedicine and public health workers,especially specialists and scholars of the Asian

  7. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    APJTB MonthlyAims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)is administrated by Hainan Medical University and sponsored by Asian Pacific Tropical Medicine Press,and aims to establish an international academic communicating platform for researchers of tropical biomedicine and public health workers,especially specialists and scholars of the Asian Pacific region and worldwide on tropical biomedicine research,to

  8. Japan's Energy Policy in the Asian Region

    OpenAIRE

    Reiji Takeishi

    2014-01-01

    With encouraged economic activities in the Asian region, energy consumption of Asian countries are substantially increasing. Based on the improved role of Asian countries, the possibility to secure enough energy in the future is becoming a seriously important matter because economic activities basically depend on stable energy supplies.

  9. Potentials in Asian Export Credit Cooperation

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    "Mekong River Regional Development Project advocated by Asian Development Bank (ADB) has been implemented. Trans-Asia Railway and Trans-Asia Highway are being discussed. It is a good opportunity for Asian Export Credit Agencies (ECAs) to cooperate and financing these large crossboarder projects."On May 11, at the 10th Annual Meeting of Asian Export Credit Agencies,

  10. [Effects of increased planting density with reduced nitrogen fertilizer application on rice yield, N use efficiency and greenhouse gas emission in Northeast China].

    Science.gov (United States)

    Zhu, Xiang-cheng; Zhang, Zhen-ping; Zhang, Jun; Deng, Ai-xing; Zhang, Wei-jian

    2016-02-01

    The traditional rice growing practice has to change to save resource and protect environment, and it' s necessary to develop new technology in rice cultivation. Therefore, a two-year field experiment of Japonica rice (Liaoxing 1) was conducted in Northeast China in 2012 and 2013 to investigate the integrated effects of dense planting with less basal nitrogen (N) and unchanged top-dressing N (IR) on rice yield, N use efficiency (NUE) and greenhouse gas emissions. Compared with traditional practice (CK), we increased the rice seedling density by 33.3% and reduced the basal N rate by 20%. The results showed that the average N agronomy efficiency and partial factor productivity were improved by 49.6% (Pefficiency. Generally, proper dense planting with less basal N applicatior could be a good approach for the trade-off between rice yield, NUE and greenhouse gas emission.

  11. Effects of extract liquid of SLS made from three different materials on seed germination and seedling growth of rice

    Science.gov (United States)

    Shao, Lingzhi; Fu, Wenting; Liu, Hong; Yan, Min; Li, Leyuan

    Rice and wheat are the main candidate crops in the bioregenerative life support system (BLSS) of China, for they are traditional food in Asia. Thus the recycling of their straws is an important issue in our BLSS, and it is a vital way to biologically process them into the soil like substrate (SLS) first and then reuse them in the plant cultivation system to achieve their recycle in BLSS. However, rice is a plant with strong allelopathic effects. And so far, it is also not clear that what kind of raw materials can be processed into proper SLS to grow rice in the BLSS. Therefore, in this study, the extract liquid of SLS made from three different materials including rice straw, wheat straw and rice-wheat mixed straw was utilized to investigate its effects on the seed germination and seedling growth of rice. The gradients of the extract concentrations (soil: water) were 1:3, 1:5, 1:9, and 1:15 with the deionized water used as control. The effects of different types of SLS on seed germination and seedling vitality of rice were confirmed by analyzing the germination rate, seedling length, root length, root fresh weight, seedling fresh weight and other indicates. In addition, based on the analysis towards pH, organic matter composition and other factors of the SLS as well as the chlorophyll and hormone content of rice, the mechanism of the inhibition was speculated and the preventive methods of this phenomenon was explored. Finally, the feasibility of cultivating rice on the SLS made from the above three kinds of raw materials was evaluated and the proper raw materials to be processed into SLS to grow rice were determined.

  12. Effects of shading on starch pasting characteristics of indica hybrid rice (Oryza sativa L..

    Directory of Open Access Journals (Sweden)

    Li Wang

    Full Text Available Rice is an important staple crop throughout the world, but environmental stress like low-light conditions can negatively impact crop yield and quality. Using pot experiments and field experiments, we studied the effects of shading on starch pasting viscosity and starch content with six rice varieties for three years, using the Rapid Visco Analyser to measure starch pasting viscosity. Shading at different growth stages and in different rice varieties all affected the starch pasting characteristics of rice. The effects of shading on starch pasting viscosity at middle and later growth stages were greater than those at earlier stages. Shading enhanced breakdown but reduced hold viscosity and setback at tillering-elongation stage. Most pasting parameters changed significantly with shading after elongation stage. Furthermore, the responses of different varieties to shading differed markedly. The change scope of starch pasting viscosity in Dexiang 4103 was rather small after heading, while that in IIyou 498 and Gangyou 906 was small before heading. We observed clear tendencies in peak viscosity, breakdown, and pasting temperature of the five rice varieties with shading in 2010 and 2011. Correlation analysis indicated that the rice amylose content was negatively correlated with breakdown, but was positively correlated with setback. Based on our results, IIyou 498, Gangyou 906, and Dexiang 4103 had higher shade endurance, making these varieties most suitable for high-quality rice cultivation in low-light regions.

  13. Educational Planning: The Asian Experience

    NARCIS (Netherlands)

    K. Jansen (Karel)

    1976-01-01

    textabstractThis article intends to present a discussion of various approaches to educational planning against the background of the experience of the Asian countries.l It may be, however, that some of our arguments apply to other parts of the Third World as well.

  14. Rice Crop Monitoring and Yield Assessment with MODIS 250m Gridded Vegetation Products: A Case Study of Sa Kaeo Province, Thailand

    Science.gov (United States)

    Wijesingha, J. S. J.; Deshapriya, N. L.; Samarakoon, L.

    2015-04-01

    Billions of people in the world depend on rice as a staple food and as an income-generating crop. Asia is the leader in rice cultivation and it is necessary to maintain an up-to-date rice-related database to ensure food security as well as economic development. This study investigates general applicability of high temporal resolution Moderate Resolution Imaging Spectroradiometer (MODIS) 250m gridded vegetation product for monitoring rice crop growth, mapping rice crop acreage and analyzing crop yield, at the province-level. The MODIS 250m Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) time series data, field data and crop calendar information were utilized in this research in Sa Kaeo Province, Thailand. The following methodology was used: (1) data pre-processing and rice plant growth analysis using Vegetation Indices (VI) (2) extraction of rice acreage and start-of-season dates from VI time series data (3) accuracy assessment, and (4) yield analysis with MODIS VI. The results show a direct relationship between rice plant height and MODIS VI. The crop calendar information and the smoothed NDVI time series with Whittaker Smoother gave high rice acreage estimation (with 86% area accuracy and 75% classification accuracy). Point level yield analysis showed that the MODIS EVI is highly correlated with