芝麻对枯萎病抗性遗传的初步研究

Study on the Inheritance of Resistance to Fusarium Wilt in Sesame

试验采用3个高抗、2个感染芝麻枯萎病的芝麻品种组配双列杂交,获得F_1、F_2代及其抗×感组合的部分回交世代,在田间人工接种条件下研究了芝麻对枯萎病抗性的遗传。结果表明:芝麻对枯萎病抗性主要表现加性遗传,其病情指数的遗传方差以一般配合力方差为主,特殊配合力方差在F_1代不显著,F_2代显著,但F_2代SCA/GCA值仍较小;Hayman法分析除表明病情指数在F_1、F_2代加性方差极显著外,给出F_1代平均显性度为0.66,抗性的狭义和广义遗传力分别为59.0%和76.0%。F_2代二类遗传力为46.6%和79.9%。5个抗×感组合的六世代均值分析进一步揭示在部分组合中存在抗性基因互作效应的方式。试验还表明,3个抗源品种中,河南一号抗性最强,抗性偏隐性;豫芝一号具有强的显性抗性基因,济源太峪白芝麻抗性稍弱,亦具显性抗性基因。文章对抗源品种在芝麻育种工作中的应用作了初步讨论。

F_1, F_2 and some backcross generations of 5×5 diallel crosses of 5 sesame varieties were used in the study. The result showed: The inheritance of resistance to Fusarium wilt in sesame was mainly controlled by additive gene effect. The Hayman's analysis indicated that Hn of the disease index was 59% and H_b was 76% in F_1, Hn was 46.5% and H_b was 79.9% in F_2. Among the three resistant cultivars, 'Henan No. 1' possessed the most additive resistant genes; 'Yuzhi No. 1' had more dominant genes. The utilization of resistant cultivars in breeding was also discussed.