Extension of the rice DH population genetic map with microsatellite markers

Genetic mapping of microsatellite markers was carried out in a rice DH population derived from across between Zaiyeqing 8 (indica) and Jingxi 17 (japonica). A total of 89 microsatellite markers, including 84 (GA)_n, 2(TCT)_n, 2(ATT)_n, and, l(ATC)_n motifs, were integrated relatively evenly into the established genetic map of the DH population. This will facilitate the utilization of microsatillite markers in rice gene mapping and marker aided breeding.     

2种非生物胁迫和7种激素对水稻OsAQP基因表达的影响

OsAQP是从cDNA文库中分离的一种新的水稻水通道蛋白基因,本实验室前期利用半定量RT-PCR技术发现该基因的表达与非生物胁迫、植物激素有关.本文采用qRT-PCR方法,检测了干旱、高盐胁迫以及ABA等7种植物激素对OsAQP在幼苗期水稻根和叶中表达的影响,结果显示干旱、高盐以及7种植物激素MeJA,SA,6-BA,GA,IAA,ABA,BR均能不同程度诱导OsAQP基因上调表达,在根中的诱导上调水平显著高于叶,提示该基因功能涉及生长发育、抗逆应答等多种生物学过程,且与水稻的根的关系更为密切.     

Transformation of japonica rice with<Emphasis Type="Italic">RHL</Emphasis> gene and salt tolerance of the transgenic rice plant

Overexpression of the yeastHAL2 gene increases salt tolerance of yeast and plant. RiceHAL2-like (RHL) gene was introduced into ajaponica rice cultivar HJ19 withAgrobacterium tumefaciens-mediated transformation. Transgenic plants in R₀ generation were selected on the principle of GUS-positive,RHL gene PCR-positive and normal growth. Hygromycin-resistant plants of some transgenic lines in R₁ generation increased salt tolerance during the seedling and booting stage, being less damaged in the cytomembrane and stronger in leaf tissue viability under salt stress during booting period. Southern analysis of transgenic lines tolerant to salt in R₁ generation showed that theRHL gene expression cassette had been successfully integrated into rice genome. Moreover, gene engineering breeding methodology and really salt-tolerant rice cultivar were discussed.     

Fine mapping of the awn gene on chromosome 4 in rice by association and linkage analyses

Awnness is a key trait in rice domestication, yet no studies have been conducted on fine mapping or association mapping of the rice awn gene. In this study, we investigated the awnness and genotype of a core collection of 303 cultivated rice varieties and a BC5F2 segregating population of 200 individuals. Combining association and linkage analyses, we mapped the awnness related genes to chromosome 4. Primary association analysis using 24 SSR markers revealed five loci significantly associated with awnness on chromosome 4. The associated markers cover previously identified regions. Fine association mapping was conducted using another 29 markers within a 4-Mb region, covering the associated marker in34, which is close to the awn gene Awn4.1. Seven associated markers were revealed, distributed over an 870-kb region. Combining the fine association mapping and linkage analysis of awnness in the 200 BC5F2 segregating population, we finally identified a 330-kb region as the candidate region for Awn4.1. The results indicate that combining association mapping and linkage mapping provides an efficient and precise approach to both genome-wide mapping and fine mapping of rice genes.     

水稻品种耐旱性鉴定的形态学评价指标研究

水稻耐早性鉴定是选育耐早水稻品种的前提。以22个水稻、陆稻和早稻品种为材料,研究了在干旱胁迫条件下,不同品种(组合)幼苗反复干旱存活率、播抽历期(日数)、株高、单穗重、着粒数、实粒数、结实率和千粒重等方面的变化趋势。苗期耐旱性鉴定中,采用幼苗反复干旱存活率,对苗期耐旱性进行评价,全生育期耐旱鉴定中,通过多重相关分析和产量结构分析,筛选出播抽历期(日数)、株高和单穗重3个与产量形成关系最密切因素的干旱胁迫指数,构成综合耐早指数,采用综合耐旱指数作为评价水稻品种全生育期耐旱性的指标,最后提出了苗期耐旱性鉴定和全生育期耐旱性鉴定的分级标准。     

160个高粱品种(系)的耐盐性鉴定

利用0.15 mol/L的NaCl对160个高粱核心品种(系)进行耐盐性筛选,以蒸馏水为对照,通过测定其萌发期苗长、根长、苗鲜质量、根鲜质量、苗干质量和根干质量6个指标,进行耐盐系数分析、隶属函数值分析及聚类分析筛选耐盐高粱种质。结果表明:0.15 mol/L NaCl胁迫处理下各个品种(系)的平均隶属函数值范围为0.059～0.639,其中编号为235、33、194、220和4这5个品种(系)的隶属函数值较大,耐盐性好,耐盐性最差的品种为62。     

藜豆种质资源遗传多样性的ISSR分子标记分析

利用ISSR标记构建了9份藜豆种质的指纹图谱,并对其遗传多样性进行评价。结果表明,从35条引物中筛选出8条重复性好的多态性引物进行PCR扩增,共扩增出64条带,其中多态性条带50条,多态性比例为78.1%。应用其中3条多态性ISSR引物(UBC889、UBC812、UBC825)的12条特异性条带,可以有效区分供试的9份藜豆种质资源。藜豆种质间的遗传相似系数变化范围在0.47⁰.97之间。利用UPGMA聚类分析,在相似性系数为0.73处可将9个藜豆种质资源划分为3个类群,其亲缘关系与种质地理来源之间存在一定关联性。     

Tagging major quantitative trait loci for sheath blight resistance in a rice variety, Jasmine 85

This study was conducted with a clonal F₂ population of rice from a cross between Jasmine 85, a resistant variety, and Lemont, a susceptible cultivar. The rice plants belonging to each F₂ clone were divided into two plots, which were put in two replicates, respectively. Clonal parents were tested as controls. The plants were inoculated by short toothpicks incubated with RH-9, a virulent isolate of the pathogenic fungus,Rhizoctonia solani, which causes rice sheath blight. The extreme resistant and susceptible clonal lines were selected for construction of resistant and susceptible DNA pools, respectively. A total of 94 polymorphic markers evenly distributed on 12 rice chromosomes were used for bulked segregant analysis, three positive ones were found polymorphic between the two DNA pools, and three major QTLs for sheath blight resistance, Rh-2, Rh-3 and Rh-7, were identified. The three major QTLs were located on chromosomes 2, 3 and 7, and could explain 14.4%, 26.1% and 22.2% of the phenotypic variation.     

SSR标记对籼稻品种的遗传多样性分析

利用500多对SSR标记对广陆矮4号、珍汕97B、佳辐占、明恢86和明恢63 5个籼稻亲本品种进行遗传多样性分析.结果表明,佳辐占与明恢63、明恢86、珍汕97B和广陆矮4号之间的相似系数分别为78.1%、76.1%、72.8%和71.7%.相对而言,其相似系数越小,遗传距离越大,因此利用佳辐占与这些品种组配较有希望选育出品质优良、综合优势明显的新品系.同时研究表明,标记间平均距离为10 cM或小于10 cM时,分析所得结果较为可靠.     

High-quality reference genes for quantifying the transcriptional responses of Oryza sativa L. (ssp. indica and japonica) to abiotic stress conditions

Rice (Oryza sativa L.) is important to food security and is also an excellent model plant for numerous cereal crops. A functional genomics study in rice includes characterization of the expression dynamics of genes by quantitative real-time PCR (qPCR) analysis; this is a significant key for developing rice varieties that perform well in the face of adverse climate change. The qPCR analysis requires the use of appropriate reference genes in order to make any quantitative interpretations meaningful. Here, the new potential reference genes were selected from a huge public database of rice microarray experiments. The expression stability of 14 candidates and 4 conventional reference genes was validated by geNorm PLUS and NormFinder software. Seven candidates are superior to the conventionally used reference genes in qPCR and three genes can be used reliably for quantitating the expression of genes involved in abiotic stress responses. These high-quality references EP (LOC_Os05g08980), HNR (LOC_Os01g71770), and TBC (LOC_Os09g34040) worked very well in three indica genotypes and one japonica genotype. One of indica genotypes including the Jasmine rice, KDML105 developed in Thailand for which no reference genes have been reported until now.     

上海市11种常规粳稻抗稻瘟病基因分子标记检测

利用分子标记检测技术,对9种参加2020年上海市水稻区域试验的品种和2种本课题组新培育的新品系的共10个抗稻瘟病基因位点进行了检测.结果显示,Pi37,Pi41,Pi-d23个基因在11种水稻中出现的频率达100％,Pi2,Pi5,Pi9,Pi36,Pikm和Pib抗性基因在11种水稻中出现的频率分别为18.18％,9...     

Transformation of japonica rice with RHL gene and salt tolerance of the transgenic rice plant

Overexpression of the yeast HAL2 gene increases salt tolerance of yeast and plant. Rice HAL2-like (RHL) gene was introduced into a japonica rice cultivar HJ19 with Agrobacterium tumefaciens-mediated transformation. Transgenic plants in R0 generation were selected on the principle of GUS-positive, RHL gene PCR-positive and normal growth. Hygromycin-resistant plants of some transgenic lines in R1 generation increased salt tolerance during the seedling and booting stage, being less damaged in the cytomembrane and stronger in leaf tissue viability under salt stress during booting period. Southern analysis of transgenic lines tolerant to salt in R1 generation showed that the RHL gene expression cassette had been successfully integrated into rice genome. Moreover, gene engineering breeding methodology and really salt-tolerant rice cultivar were discussed.     

水稻遗传多样性及其农艺性状与SSR标记的关联分析

分析水稻材料的遗传多样性,寻找与农艺性状相关联的分子标记,为水稻杂交组合的配置及分子标记辅助育种提供依据.利用60对分布于水稻12条染色体组的SSR标记对190份水稻材料进行遗传多样性分析与群体遗传结构分析,并采用Tassel3.0的GLM和MLM进行标记与农艺性状的关联分析.结果显示,190份水稻材料的遗传相似系数(GS)变异范围为0.62～0.97,平均值为0.86.按群体遗传结构可将供试材料分为3个亚群.以GLM分析,发现8个与穗长、一次枝梗数、一次枝梗穗粒数、二次枝梗数、二次枝梗穗粒数、总穗粒数和饱满穗粒数相关联的标记,各标记对表型变异的解释率为0.0648;以MLM分析显示,8个标记对表型变异的解释率在0.0378～0.0648.本研究获得的这8个农艺性状相关的分子标记可以作为辅助育种培育高产水稻品种的分子标记.     

水稻悬浮细胞系的建立

 对包括广亲和材料、恢复系、花培后代在内的30个水稻不同基因型的品种(系)在MS培养基中的培养能力进行了调查.根据出愈率的高低和愈伤组织培养能力,把它们分成Ⅰ,Ⅱ,Ⅲ3种类型.从Ⅰ类型中挑选CPSLO17和IR21820-154-3-2-2-8用N₆液体培养基进行液体培养,CPSLO17建立了悬浮细胞系,证实基因型的差异是决定建立良好悬浮细胞系的关键因素之一.此外还考察了低锌胁迫对水稻悬浮细胞系和幼胚愈伤分化率的影响.     

Relationships between D1 protein, xanthophyll cycle and photodamage-resistant capacity in rice (Orysa sativa L.)

Relationships between D1 protein, xanthophyll cycle and subspecific difference of photodamage-resistant capacity have been studied inO. japonica rice varieties 02428 and 029 (photoinhibition-tolerance) andO. indica rice varieties 3037 and Palghar (photoinhibition-sensitivity) and their reciprocal cross F₁ hybrids after photoinhibitory treatment. It was shown that PS II photochemical efficiency (F _v /F _m) decreased, and xanthophyll cycle from violaxanthin (V), via anaxanthin (A), to zeaxanthin (Z) was enhanced and non-photochemical quenching (qN) increased accordingly in SM-pretreated leaves of rice when the synthesis of D1 protein was inhibited, and that there was a decrease inqN and, as a result, more loss of D1 protein and a big decrease inF _v/F _m in DTT-pretreated leaves when xanthophyll cycle was inhibited.O. japonica subspecies had a higher maintaining capacity of D1 protein and a decrease ofF _v/F _m in a more narrow range, and exhibited more resistance against photodamage, as compared withO. indica subspecies. The above physiological indexes in reciprocal cross F₁ hybrids, though between the values of their parents, were closer to maternal lines than to paternal lines. Experimental results support the concept that the turnover capacity for D1 protein is an important physiological basis of photoinhibition-tolerance, and will provide the physiological basis for selection of the photoinhibition-tolerant parents and develop a new approach to breed hybrids with high photosynthetic efficiency.     

Characterization of Arabidopsis calreticulin mutants in response to calcium and salinity stresses

As an important calcium-binding protein, calreticulin plays an important role in regulating calcium homeostasis in endoplasmic reticulum （ER） of plants. Here, we identified three loss-of-function mutants of calreticulin genes in Arabidopsis to demonstrate the function of calreticulin in response to calcium and salinity stresses. There are three genes encoding calreticulin in Arabidopsis, and they are named AtCRT1, 2, and 3, respectively. We found that both single mutant of crt3 and double mutant of crtl crt2 were more sensitive to low calcium environment than wild-type Arabidopsis. Moreover, crt3 mutant showed more sensitivity to salt treatment at germination stage, but tolerance to salt stress at later stage compared with wild-type plant. However, there was no obvious growth difference in the mutant crtl and crt2 compared with wild-type Arabidopsis under calcium and salt stresses. These results suggest that calreticulin functions in plant responses to calcium and salt stresses.     

江汉平原湖区洪涝灾害形成机理与生态减灾的对策研究

江汉平原湖区由于长江干、支流中上游水流失与湖泊沙瘀积，过度围湖景殖，堤防财团及高水位地段农业布局与种植制度不合理等原因其洪涝灾丰发生次数增多损失加重，通过分析该区洪涝灾害的形成机理，提出生态减灾的对策；强化流域生态减灾意识；适度退田还湖，增加蓄洪能力；加强分、蓄洪区的建设；建立适应 生规律的耐溃农业模式体系，避洪农业。