Oryza

摘要： Many excellent genes in wild rice have been lost during the domestication of wild rice to cultivated rice.In this study,introgression lines(ILs)were produced with a wild rice(Oryza rufipogon)accession,BJ194,as a donor parent and an indica restorer line,Zhonghui 8015(ZH8015),as a recipient parent to map QTLs for plant height.We identified four QTLs(qPH3.1,qPH3.2,qPH2,and qPH8)related to plant height distributed on chromosomes 2,3 and 8.Furthermore,we sequenced and analyzed qPH3.2 located in the interval of RM15753-RM3525,and found this QTL may be a new locus regulating rice plant height.

摘要： Rice is food for more than half of the world population and the most consumable cereal in most of the countries. Pakistan is the fifth largest exporter of rice. However, Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae is the most devastating and serious threat to rice production in many countries of the world including Pakistan. To combat this disease, innate genetic resistance of the plant plays vital role along with being environmentally friendly and economical. In this study, thirty-one (31) Near Isogenic Lines (NILs) having Xa4, xa5, Xa7, xa13 and Xa21 reported BLB tolerant genes and 34 locally developed rice lines were investigated under natural field conditions at three agro-ecologically different locations with highest disease occurrence records (BLB hotspots) viz., Sheikhupura, Hafizabad and Gujranwala, Punjab, Pakistan in order to assess their respective genetic resistance and G × E interactions against the disease. Thirty-one (31) lines were categorized under resistant cluster, twenty-eight (28) were moderately resistant, six (6) were moderately susceptible and one (susceptible check) was in susceptible category. Grouping of different lines/varieties under same cluster shows their significantly similar response against BLB disease in corresponding environment. Among the studied NILs, only one line showed polymorphism for all five resistant genes, two lines had four;seven lines had three genes, seven lines showed di-genic while five lines showed mono-genic polymorphism. These resistant lines with multiple-genes for BLB resistance can be evolved as a new BLB resistant variety and also be utilized as donor parent in breeding programs for developing new cultivars with horizontal resistance against more than one target pathotypes and environments. Xa4 and xa13 were found to deliver significant resistance against the local pathotypes in studied germplasm and NILs.

摘要： Black rice Oryza sativa is primarily grown in East and North East of India. This variety could not become popular due to low yield and being expensive. It is rich in three kinds of Anthocyanin contents which exhibit great impact on human health. Four different kinds of ZnO nanomaterial were prepared at variable temperature ranging from 250°C to 500°C. The Interaction of black rice grain with nanozinc material leads to the observation that seeds germinated early. Rooting development was higher. Better effects were observed while those interacted with nanomaterial prepared at 350°C. In the present study the aim was to enhance the yield and value addition. To best of our knowledge this is the first scientific attempt [see also patent filed Varma et al. 2019]. The mechanism involved needs further elaborate elucidation. We hope that the goal can also be achieved by interaction of seeds with mycosymbiont—Piriformospora indica (Serendipita indica) a potent cultivable mycorrhiza. The precise objective of this communication is to illustrate the interaction of black rice seed with several synthesized nano zinc material which varied in shape, size and diameter.

摘要： 为了因地制宜地发展控制灌溉,减少不合理的栽培措施对产量的损失,选定适宜的作物播种期是十分必要的。本研究基于昆山地区控制灌溉水稻田间实测数据对ORYZA v3模型进行校正和检验,进而模拟昆山地区1971—2010年(40年)不同气候条件下控灌水稻的生长情况,根据模型输出的DVS值,分析不同可播期水稻生育期长度、产量等相关因素,最终确定该地区控灌水稻的适宜播种期。模型校正和检验的RMSEn值在9%~26%之间,决定系数R2在0.85~0.99之间,模型具有良好的适用性。根据DVS值,确定多年控制灌溉水稻最早和最晚可播期为3月28日和6月13日,以最高产量为目标选定播种日期为5月23日至6月13日。推荐5月23日至6月3日为苏南地区控制灌溉水稻的适宜播种期。

摘要： Floods have now become most detrimental natural catastrophe worldwide due to radical climatic fluxes. Therefore, there is a dire necessity to develop a high yielding rice lines to deal with this scenario. For this purpose, a large scale experiment was conducted including one hundred and fifteen (115) rice genotypes having SUB1 gene imported from International Rice Research Institute (IRRI) Philippines, six local cultivars/approved varieties and three high yielding rice varieties i.e. Sabitri, IR6 and NSICRC222 being used as potential varieties in different countries of Asia as susceptible check and IR64-SUB1 as tolerant check. The genotypic screening was performed using two PCR-based DNA markers i.e. ART5 and SC3. Phenotypic screening was conducted in a natural pond to assess the interaction of SUB1 gene in natural stagnant flood water as well as the suitability of introgression of SUB1 gene into approved varieties and elite rice lines. The genotypes were assessed in terms of plant survival percentage, submergence tolerance index, physical condition, stem elongation, number of grains per panicle, thousand grain weight, grain yields and deviations in these traits after submergence stress. The PCR results suggested that both the primers ART5 and SC3 may be used as potential PCR-based markers for molecular screening of rice genotypes for SUB1 QTL. Furthermore, it confirmed the presence of SUB1 gene in all the lines imported from IRRI, while it was absent in all the local cultivars studied. All the genotypes with submergence tolerant gene (SUB1) showed significantly greater tolerance level in submergence stress of 14 days, as compared to other local cultivars/varieties, authenticating the effectiveness of SUB1QTL in conferring submergence tolerance. Significantly different performances of all the SUB1 genotypes in terms of all the studied traits indicate high Genotypic and Genotypic Environment Interaction (GEI) of SUB1QTL. Employment of SUB1 lines such as R105479:149-18, IR64-SUB1 and Rl05469:81-22-3 in breeding programs for developing flood tolerant rice varieties might further upsurge rice yields in flash flood areas. Correlation analysis revealed that plant survival percentage after submergence, reduced stem elongation during submergence and submergence tolerance index are very important traits for developing submergence tolerant lines.

摘要： Rice (Oryza sativa L.) presents a strategic role in social and economic levels. The aim of this study was to elucidate the presence of genetic variability for the genus Oryza, and the possibility of using genotypes with wild characteristics in rice breeding programs. The Oryza genus shows great genetic variability through wild genotypes available in the most varied environments around the world. The negative effects imposed by abiotic stresses such as flood, salinity, low temperatures, water deficiency and high temperatures may be minimized by the efficient identification of a genetic variability source from the Oryza genus. Among the main wild species presented by the Oryza genus, Oryza glumaepatula stands out being an active source of germplasm. The occurrence and preservation of genetic variability of Oryza genus is indispensable to obtain new rice genotypes, to guarantee food security for the human population, as well as to develop genotypes that adapt to climatic changes and natural adversities.

摘要： The KNOX gene family codes for transcriptional regulators with a variety of functions in plant developmental and physiological processes. In this study, a genome-wide comparative analysis of KNOX genes in Poplar (Populustrichocarpa) and rice (Oryza sativa L. ssp. japonica) was carried out. With comprehensive computational analyses, which take into account the gene structures, phylogeny and conserved motifs, 15 and 13 KNOX genes in Poplar and rice were identified, respectively. These KNOX genes were further divided into 3 groups. The Poplar gene POPTR_0012s04040 and the rice genes LOC_Os03g47042 and LOC_Os03g47022 were classified to a new group of KNOX genes without ahomeobox domain together with KNATM, which were proposed to play potential role in plant development and pluripotency. The identification of KNATM homolog in monocotyledons (rice) provided a strong support for proposing an ancient shuffling of HOMEOBOX gene with MEINOX gene took place in the KNOX phylogeny. Using subcellular location information, GO (gene ontology) and expression profile analysis, KNOX genes in rice and poplar were proposed to function similarly to the members in Arabidopsis. Our observations may lay the foundation for future functional analysis of KNOX genes in rice and poplar to unravel their biological roles in cellular pluripotency.

摘要： The objective of this study is to identify and quantify the floristic composition of the weed community in the rice crop waterlogged in the municipality of Arari-MA. The botanical material was obtained in three areas by randomly a hollow rectangle of 0.50 m × 0.30 m by forty five times in each plot. The aerial parts of weeds were harvested, identified, counted and oven dried with forced air ventilation at 333.15 K to 343.15 K. These data were used to determine the phytosociological parameters and the Shannon-Wiener diversity index was also calculated. A total of 6607 plants were collected, being 4115 (62.28%) in the vegetative phase and 2492 (37.72%) in the reproductive phase. The monocotyledonous group obtained the largest number of plants, 2882 in the vegetative phase and 1535 in the reproductive phase. The Cyperaceae family recorded nine species and four genera and the Poaceae, seven and four species in the vegetative and reproductive phases, respectively. The species of higher IVI in the vegetative phase was E. sellowiana in the area A1 with 82.86%, and in the reproductive F. dichotoma with IVI of 90.49% in the area A3. The individuals density and species richness were higher in the vegetative phase of the culture and the monocotyledonous group predominated with the Cyperaceae and Poaceae families, and the weed diversity among the areas was low.