水稻芽期耐冷性QTL的分子定位

 以籼粳交密阳23号/吉冷1号的F2：3 代200个家系作为作图群体，构建了一张含有97个微卫星 （SSR）标记的分子连锁图谱。在5℃低温条件下，对F3家系进行芽期耐冷性鉴定，并利用SSR标记进行了芽期耐冷性数量性状位点（QTL）分析。研究结果表明，芽期耐冷性在F3家系群中呈单峰连续分布，表现为由多基因控制的数量性状；共检测到与芽期耐冷性有关的QTL 3个，分别位于第2、4 和7染色体上，对表型变异的贡献率范围为11.5%～20.5%。其中，位于第4染色体RM273～RM303的qCTBP4对表型变异的贡献率最大。

Molecular Mapping of QTLs for Cold Tolerance at the Bud Bursting Period in Rice

The quantitative trait loci (QTLs) for cold tolerance at the bud bursting period (CTBP) were identified by using a F2:3 population including 200 lines derived from a cross of indica and japonica Milyang 23/Jileng 1. A molecular linkage map of 97 SSR markers was constructed by using interval mapping and covered a total length of 1357.3 cM with an average distance of 13.99 cM, between adjacent markers in rice genome. The CTBP of F3 lines was evaluated at 5℃, and the percentage of seedling stand after treated under low temperature at the bud bursting period was used as cold tolerance index for CTBP. A continuous distribution near to normal for CTBP was observed in F3 lines, CTBP is a quantitative trait which was controlled by some genes. Three QTLs on chromosome 2, 4 and 7 which are associated with CTBP were detected on location of RM6-RM240, RM273-RM303, RM214-RM11, respectively, which explained the range of the observed phenotypic variance from 11.5% to 20.5%. qCTBP4, which is detected on RM273-RM303 of chromosome 4, is explained 20.5% of the observed phenotypic variance. The effect of qCTBP4's allelic gene comes from Jileng1.