烟草品种Beinhart1000-1抗黑胫病基因的QTL定位

为研究烟草黑胫病不同亲本来源的抗性遗传规律,定位抗性基因位点,本研究利用抗黑胫病品种Beinhart1000-1构建了220个F2分离群体。通过病圃接种鉴定和遗传分析,确定Beinhart1000-1对烟草黑胫病的抗性由多基因控制。利用筛选到的70对稳定SSR引物对烟草黑胫病抗性进行了QTL分析,绘制了一张包含14条染色体的遗传连锁图谱,且定位到5个与烟草黑胫病抗性紧密相关的QTLs,分别在2、3、3、6、12号染色体上,其贡献率分别为6.2%、6.0%、6.7%、5.6%和5.1%。此结果使烟草黑胫病抗性研究进一步深入,推进了烟草黑胫病分子标记辅助选择。

Mapping of quantitative trait loci affecting resistance to black shank in tobacco line Beinhart1000-1

To study the genetic regularity of tobacco black shank resistance of different parents, and to identify the genomic locations contributing to the resistance, 220 F2 populations were constructed from a cross between Beinhart1000-1 and susceptible variety, xiaohuangjin1025. Through disease inoculation and genetic analysis, we found that the resistance to black shank of Beinhart1000-1 was controlled by the dominance genes. 70 stable SSR primers were used for QTL mapping of resistance to black shank. We got 14 linkage groups which included 52 SSR markers. Five QTLs are discovered on No.2, No.3, No.3, No.6 and No.12 genetic linkage groups, and account for 6.2%, 6.0%, 6.7%, 5.6% and 5.1% of the phenotypic variance, respectively. In order to further study the genetic regularity of tobacco black shank resistance of different parents, and to posit the resistance gene loci, the 5 SSR markers has certain value in marker-assisted breeding. These results could facilitate our understanding of the inheritance of resistance to black shank in tobacco by marker-assisted selection.