抗根肿病青麻叶近等基因系的高效选育技术体系研究

Study on High Efficiency Breeding Technology System for Near-isogenic Lines(NILs)of Brassica campestris Resistant to Clubroot Disease

为提高分子标记辅助选育大白菜抗根肿病近等基因系的筛选效率,以抗根肿材料G 57作为供体亲本,具有优良性状的感病材料H_(2)27作为轮回亲本,利用分子标记前景及背景选择的方法,分别从分子标记筛选的群体数量以及开展轮回亲本背景选择的最初世代等方面加以研究,探究了影响筛选效率的几个重要因素。结果发现,各回交群体样本量为18时,目标单株的筛选效率最佳;同样本量下,从BC_(2)F_(1)代起开展背景筛选,获得理想单株的概率最高,群体内变异系数最小。试验通过对植株遗传回复率的分析,探索了适宜青麻叶大白菜根肿病的高效分子选育技术体系,加速了青麻叶大白菜抗根肿近等基因系的构建进程。

To improve the screening efficiency of near-isogenic lines(NILs)of Chinese cabbage resistant to clubroot disease by molecular marker-assisted selection,The clubroot-resistant material G 57 was used as the donor parent,and the susceptible material H_(2)27 with excellent traits was used as the recurrent parent.By using the method of foreground and background selection of molecular markers,we studied the number of population screened by molecular markers and the initial generation of recurrent parental background selection,and several important factors affecting the screening efficiency were also explored.The results showed that when the sample size of each backcross population was 18,the screening efficiency of target single plant was the best,and background screening from BC_(2)F_(1)generation had the highest probability of obtaining ideal single plant and the lowest coefficient of variation within the population under the same sample size.Through the analysis of the genetic recovery rate of the plant,the efficient molecular breeding technology system suitable for clubroot was explored,which accelerated the construction process of near-isogenic lines of resistance to clubroot in Chinese cabbage.