大白菜细胞核复等位雄性不育基因定位

以大白菜不育材料"939A"为母本,携带恢复基因的材料YDQ56A为父本构建隐性雄性不育F1S4分离群体,利用混合分组分析法(BSA)对不育基因初定位;同时以"939A"为母本,携带保持基因的材料yellow sason为父本构建显性雄性不育F2分离群体,对不育基因进行精细定位。结果在F1S4群体中获得与不育基因连锁的标记2个,A08_1900和Br ID111035,与不育基因分别相距8.8c M和2.5c M,物理距离为804.1kb;F2群体中不育单株与可育单株分离比符合3∶1,不育基因表现为显性。通过标记验证,F2和F1S4两个群体定位结果一致,均位于A08染色体末端,通过新标记的筛选获得不育基因两侧紧密连锁的标记Br19470306和Br19675586,与不育基因分别相距1.6c M和2.4c M,物理距离205.28kb,其中包含58个基因。该结果为大白菜雄性不育系的利用以及转育奠定了基础。

Fine Mapping of the Multi-allele Genic Male Sterility Gene in Brassica rapa L. ssp. pekinesis

Multi-allele Genic male sterility is one of the most important methods for hybridization breeding in Chinese cabbage (B. rapa L. ssp. pekinensis). A segregating population F1S4 from a cross between a male sterile line 939A and a fertile line YQD56A which contained restoring gene was developed. Bulked segregate analysis (BSA) was used to screen markers linked to the MS gene. At the same time, an F2 population from a cross of 939A and a fertile line yellow sason which contained maintainer gene was received for the confirmation of the location and fine mapping of MS. Bulked segregate analysis (BSA) was used to screen markers linked to the MS gene. Finally 2 markers, A08_1900 and BrID111035, were found in F1S4 population, linked to MS. The distance was 8.8 cM and 2.5 cM, respectively. In F2 population, the MS were mapped in the same region in chromosome A08 with its in F1S4 population. Further, Br19470306 and Br19675586 were found tightly linked to MS. The distance was 1.6cM and 2.4cM, respectively.In this region, 58 genes were found. These results can be used for finding the candidate gene of MS and then accelerate breeding programs.