水稻条斑病抗性QTL的挖掘及相关基因的表达

条斑病是水稻(Oryza sativa)中的常见病害, 已经对我国粮食的高产稳产造成严重威胁。以典型籼稻台中本地1号与粳稻春江06的杂交F₁代花药培养双单倍体群体(DH)为材料, 用Xoc BLS256进行人工接菌, 对双亲及群体各株系的病斑长度进行测量和量化分析; 同时利用该群体业已构建的加密遗传图谱对病斑表型数据进行QTL作图分析。结果在水稻第2、4、5和8号染色体上共检测到4个效应值能区分开的QTL。对2号与5号染色体上2个较大的QTL区间内抗条斑病相关基因进行了表达分析, 结果表明这些基因在处理前后出现了不同程度的表达差异, 暗示这些基因可能是响应春江06与台中本地1号条斑病抗性差异的目标基因。研究结果为进一步克隆水稻条斑病抗性QTL奠定了重要基础。     

Identification and Expression Analysis of Ras Gene in Silkworm,Bombyx mori

Ras proteins play important roles in development especially for cell proliferation and differentiation in various organisms. However, their functions in the most insect species are still not clear. We identified three ras cDNAs from the silk worm, Bombyx mori. These sequences corresponded to three Ras of Drosophila melanogaster, but not to three mammalian Ras (H-Ras, K-Ras, N-Ras). Subsequently, the expression profiles of ras were investigated by quantitative real-time PCR using whole body of individuals from the embryonic to adult stages, and various tissues of 4th and 5th instar larvae. Each of three Bombyx ras showed different expression patterns. We also showed membrane localization of their products. These results indicate that the three Bombyx Ras are functional and have different roles.     

Defense Responses in Rice Induced by Silicon Amendment against Infestation by the Leaf Folder Cnaphalocrocis medinalis

Silicon (Si) amendment to plants can confer enhanced resistance to herbivores. In the present study, the physiological and cytological mechanisms underlying the enhanced resistance of plants with Si addition were investigated for one of the most destructive rice pests in Asian countries, the rice leaf folder, Cnaphalocrocis medinalis (Guenée). Activities of defense-related enzymes, superoxide dismutase, peroxidase, catalase, phenylalanine ammonia-lyase, and polyphenol oxidase, and concentrations of malondialdehyde and soluble protein in leaves were measured in rice plants with or without leaf folder infestation and with or without Si amendment at 0.32 g Si/kg soil. Silicon amendment significantly reduced leaf folder larval survival. Silicon addition alone did not change activities of defense-related enzymes and malondialdehyde concentration in rice leaves. With leaf folder infestation, activities of the defense-related enzymes increased and malondialdehyde concentration decreased in plants amended with Si. Soluble protein content increased with Si addition when the plants were not infested, but was reduced more in the infested plants with Si amendment than in those without Si addition. Regardless of leaf folder infestation, Si amendment significantly increased leaf Si content through increases in the number and width of silica cells. Our results show that Si addition enhances rice resistance to the leaf folder through priming the feeding stress defense system, reduction in soluble protein content and cell silicification of rice leaves.     

Expression of 10 kD Sulfur-Rice Prolamin Gene of Rice in Potato

Using 10 kD sulfur-rich prolamin gene of rice (PLG) as target gene, the authers constructed the expression vectors pBinLG and pBinLGP, which contained CaMV 35S promoter/PLG/NOS terminator, and Patafin Class Ⅰ promoter/PLG/NOS terminator respectively. They were transformed into Agrobacterium tumefaciens strain LBA4404 (pAL4404) by direct transformation method with incubating the leaf and tuber explants of potato (Solanum tuberosum L. ) with LBA4404 (pAL4404) and selecting in the medium containing 100 mg/L kanamycin, regenerated resistant plants were obtained. The NPT Ⅱ enzyme activity analysis, polymerase chain reaction (PCR), Southern blotting, Northern dot blotting and Western blotting demonstrated that the target gene was integrated into the genome of potato ceils and well expressed in the plant.     

水稻XIOsPR10基因表达调控的初步研究

为探索水稻PR10蛋白在水稻抗细菌性条斑病中的作用,构建了XIOsPR10基因的植物过量表达载体p1301-XIOsPR10及RNAi表达载体pDS1301-XIOsPR10,通过农杆菌介导分别转化水稻愈伤组织,获得了相应的再生植株.经GUS检测和PCR分析,证实XIOsPR10基因以及RNAi片段分别整合到水稻再生植株基因组中;半定量RT-PCR分析显示,过量表达植株中XIOsPR10基因的表达量高于对照,而RNAi转基因植株中XIOsPR10基因的表达被抑制.     

水稻叶片水势的QTL定位与候选基因分析

为探究叶片水势(LWP)相关基因在水稻(Oryza sativa)抗旱中的作用及其遗传机制,以热研2号(Nekken2)和华占(HZ)为亲本以及构建的120个重组自交系(RILs)群体为实验材料,对水稻分蘖期叶片水势进行检测,并利用前期基于高通量测序构建的分子遗传连锁图谱进行数量性状基因座(QTL)分析。结果表明,共检...