水稻抽穗期基因的精细定位、克隆和生物学功能分析

介绍了水稻抽穗期QTL研究的进展，在相同亲本日本晴/Kasalath衍生的不同类型的多个群体中，共检测到15个QTL；应用高世代回交后代，精细定位了其中8个QTL；将在初步定位时同一区间检测到的1个控制种子休眠期QTL(Sdr1)和1个抽穗期QTL (Hd8),分解为两个紧密连锁的基因；将经过精细定位表明可能具有双重功能的单个孟德尔因子Hd3，分解为两个功能不同的紧密连锁的基因Hd3a和Hd3b；根据QTL近等基因系的光周期反应以及这些座位间上位性互作的研究，明确了其中6个QTL的生物学功能；应用图位法克隆了其中3个QTL，研究了它们的表达和调控，并与拟南芥的同源基因进行比较。为水稻其他数量性状以及其他作物数量性状的遗传学研究，提供了一个范例。

Fine Mapping,Cloning and Biological Function Analysis of Heading Date QTLs in Rice

Recent progresses in genetic study of heading date in rice were described. Fifteen QTLs for heading date were detected in several segregating populations derived from the same parents Nipponbare and Kasalath. Eight QTLs were finely mapped in the advanced backcross progenies. A seed dormancy QTL(Sdr1) and a heading date QTL(Hd8), which were mapped in the same interval in initial mapping, were dissected into two tightly linked loci. Hd3, which was finely mapped as single Mendelian factor with double functions in photoperiod response, was dissected into two tightly linked loci (Hd3a, Hd3b) with different functions. The involvement of six QTLs in photoperiod response was determined based on the performances of near isogenic lines of QTLs and epistatic interactions between these QTLs.Three QTLs (Hd1, Hd6 and Hd3a) were cloned by map-based cloning. The expression and their regulation were studied and comparisons between the heading date genes in rice and the flowering time genes in Arabidopsis were carried out. These results set a good example for the genetic study of other quantitative traits in rice and quantitative traits in other crops as well.