短季棉早熟及相关性状的QTL定位

QTL Location Study on Earliness and its Related Traits of Short Season Cotton

短季棉育种是缓解我国当前粮棉争地矛盾、实现粮棉双丰收的有效途径。研究短季棉早熟及相关性状的遗传,寻找与其相关基因紧密连锁的分子标记对于短季棉育种具有重要意义。以百棉2号×TM-1组合构建的F2为作图群体,利用SSR标记构建遗传连锁图,采用复合区间作图法对短季棉早熟及相关性状在F2群体中进行QTL定位,构建了一张含152个SSR标记、40个连锁群、总长1010.3cM、覆盖棉花基因组的22.6%、标记间平均距离为5.91cM的短季棉分子标记遗传连锁图谱,得到的40个连锁群已定位到相应的21条染色体上,为短季棉分子遗传图谱进一步饱和奠定了良好的基础;检测出22个控制早熟及相关性状的QTL,其中检测到的主效QTL可用于短季棉标记辅助选择育种。

The breeding of short season cotton cuhivars is an efficient way to solve the problem of the limited farmland reserve and reap a bumper harvest of grain and cotton in China. The genetic research about earliness and its related traits of short-season cotton and findings of the molecular markers closely linked with earliness genes are significant to short season cotton breeding. In the present study, based on F2 individuals from Baimian 2 and TM - 1 as the mapping population, SSR molecular markers applied in constructing genetic linkage map and the composite interval mapping method used to locate QTL in F2population for earliness and its related traits of short-season cotton, 152 SSR molecular markers were assigned to 40 linkage groups with a total map distance of 1,010.3 cM and an average distance of about 5.91 cM between the two markers, covering approximately 22.6% of the total recombination length of the cotton genome, and 40 linkage groups were tentatively assigned to 21 chromosomes, which laid a good foundation for molecular genetic map construction of short season cotton. 22 QTL for earliness and related traits were identified, and the molecular markers linked closely to the major QTL could be used in MAS （marker-assisted selection） breeding of short season cotton.