一个新的水稻花粉半不育性位点的定位分析

利用一套以籼稻珍汕97B为背景的粳稻日本晴染色体片段代换系，鉴定发现1个半不育的代换系。全基因组基因型分析表明，该代换系仅含3个粳稻导入片段，而其他遗传背景与珍汕97B相同。在湖北武汉和海南分别种植其衍生的F₂和F₃分离群体，采用单标记分析和区间作图法分析花粉育性和小穗育性的数量性状位点(QTL)，结果表明，该代换系的半不育性是第2染色体上的粳稻导入片段引起的，该片段RM262~RM475区间存在1个新的影响花粉育性的QTL，其贡献率为13.9%。研究结果将为进一步精细定位水稻育性QTL以及鉴定相关功能基因提供重要的试验基础。

Mapping of a Novel Semi-Sterile Pollen QTL in Rice

Hybrid sterility has been an obstacle in utilization of potential heterosis in inter-subspecific hybrids of indica and japonica.In order to understand the genetic basis of pollen sterility of indica-japonica hybrid, we identified a line (IL37) with semi-sterility from a set of chromosomal segment substitution lines, of which each contained a single or few substitution segments from a japonica variety Nipponbare in the genetic background of indica variety Zhenshan 97B. The graphical genotype analysis of the line (IL37) by using 160 polymorphic SSR revealed that there were three chromosomal segments from the japonica with the similar genetic background of Zhenshan 97B. Its derived F₂ and F₃ segregation populations were planted respectively in Wuhan and Hainan, and evaluated for quantitative trait loci (QTLs) conferring pollen fertility and spikelet fertility via single-marker analysis and interval mapping. One new QTL of pollen sterility was detected at the interval RM262–RM475 on chromosome 2, explaining the phenotypic variation of 13.9%. The results suggest that japonica substitution segment carrying the QTL is a major cause of the semi-sterility in IL37. Further fine mapping and identification of candidate genes in the QTL region would facilitate a better understanding of the genetic basis of pollen sterility in rice.