小麦“BS20×Fu3”DH群体SSR遗传图谱的构建及不育基因的QTL定位

Construction of a SSR Genetic Linkage Map of Wheat Using DH Population Derived from BS20 × Fu3 and Mapping QTLs for Sterile Gene

以小麦光温敏核雄性不育系BS20×Fu3双单倍体（DH）群体的289个系为材料,从1112对SSR和EST-SSR引物中筛选出多态性引物243对,利用其中128个SSR和6个EST-SSR标记构建遗传连锁图谱,该图谱覆盖长度为2749.2 c M,分布在小麦的19个连锁群（除4D、6A）,不同连锁群标记数为2-15个,长度在15.3-244.4 c M之间,平均长度为144.7 c M,标记之间平均遗传距离为17.4 c M。同时构建3个DNA池（包括恢复池、北京不育池和阜阳不育池）,用分离群体分组分析法（BSA）对育性进行分析,筛选出的多态性引物为Wmc264、Wmc73、Xgwm350,分布在3A、5B、2A/7D染色体上。同时用混合线性复合区间作图法（MCIM）对育性进行QTL分析,当F〉7.5时,检测到6个主效QTL,用复合区间作图法（CIM）对育性进行QTL分析,当LOD值〉2.5时,共检测到13个主效QTL,两种方法检测到一致的QTL有3个,分别为1BL的Wmc365-cfa2129、2BS的Wmc602-Xgwm148和3AL的Wmc264a-cfa2262区间的QTL。综合BSA和QTL的结果,位于1BL、2BS和3AL上的小麦光温敏不育基因是真实的。

The genetic linkage map of wheat was constructed with DH population consisting of 289 individuals from a cross between BS20 and Fu3. 1112 SSR and EST-SSR primers were used to detect the polymorphisms between the parents. Applying QGA_CN software to carry out linkage analysis,the genetic map covered 19 chromosomes except 4D and 6A which included 128 SSR and 6 EST-SSR markers. The linkage map covered 2749. 2 c M and the average distance was 17. 4 c M. All 19 linkage groups consisted of 2-15 markers,with the coverage of length from 15. 3 to 244. 4 c M. At the same time,we constructed three DNA pools including Beijing sterile pool,Fuyang sterile pool and restorer pool for screening the sterile genes using BSA method,and these primers were Wmc264,Wmc73 and Xgwm350,which distributed by chromosomes 3A,5B and 2A /7D. Six major QTLs were detected when the F value 7. 5 by mixed-model composite interval mapping. Thirteen major QTLs were found when the LOD value 2. 5 with composite interval mapping. After the analysis of BSA and QTL,three QTLs were shared from two methods,the sterile genes were located on chromosomes 1BL,2BS and 3AL,the marker intervals were Wmc365-cfa2129,Wmc602-Xgwm148 and Wmc264a-cfa2262,respectively. The photoperiod-thermo sensitive genic sterile genes were realy located on 1BL,2BS and 3AL.