水稻第6染色体短臂上株高QTL qPH6-1的精细定位

摘要

Populations derived from residual heterozygous lines (RHLs) were used for the detection and fine mapping of quantitative trait loci (QTLs) for plant height in rice. An F_(2:3) population which segregates in a 7.3-Mb region on the short arm of rice chromosome 6 in an isogenic background were transplanted in two trial sites in Hainan and Zhejiang Provinces, respectively. Two QTLs for plant height were detected, of which qPH6-1 exhibited a consistent effect across the two sites. Three plants having smaller heterozygous segments which overlap the qPH6-1 region were selected. Using the three F_2 populations produced, qPH6-1 was validated and delimitated to a 96.4-kb region flanked by SSR markers RM3414 and RM19417. Three more F_2 populations which segregate in smaller regions covering qPH6-1 were developed. The qPH6-1 locus was delimited to a 51.7-kb region flanked by STS marker Si2925 and SSR marker RM19417. It was also shown that this gene is non-allelic to all the major genes for dwarfism mapped or cloned in rice.%应用衍生于水稻剩余杂合体的分离群体,开展株高QTL的检测和精细定位.应用1个在水稻第6染色体短臂约7.3 Mb区间分离、背景基本纯合的F_(2:3)群体,种植于海南、浙江两地,检测到2个控制株高的QTL;然后,针对两地间作用稳定的qPH6-1,筛选出3个杂合区间缩小且呈阶梯状排列的单株,衍生F_2群体,进一步验证了qPH6-1的作用,并将其界定于距离为96.4 kb的SSR标记RM3414和RM19417之间;最后,应用分离区间进一步缩小且呈阶梯状排列的3个F_2群体,将qPH6-1定位于距离为51.7 kb的STS标记Si2925和SSR标记RM19417之间.基因组位置比较结果显示,该基因与所有已定位或克隆的水稻矮秆、半矮秆基因均非等位.