陆地棉对黄萎病抗性的分子标记研究

Detection of DNA markers associated with resistance to Verticillium dahliae in cotton

利用陆地棉标准系TM-1和常抗棉2个陆地棉品种杂交并自交,获得109个F2单株及F2:3家系为作图群体,以SSR、RAPD和SRAP 3种分子标记进行抗黄萎病性状的分子标记筛选。结果从1 611对(条)引物中仅筛选到70对(条)多态性引物,获得75个多态性位点并进行标记间的连锁性分析。75个标记构建了一个包括15个连锁群,全长535 cM的陆地棉品种间分子标记遗传连锁图,标记间平均距离为11.15 cM,有27个标记不能进入任何连锁群。连锁群的标记数最少2个,最多6个;长度从1.0 cM到92.7 cM不等。对其F2:3家系的成株期抗黄萎病性状即平均病情指数的分布进行分析,显示其呈正态分布,进一步说明陆地棉对黄萎病的抗性为数量遗传;单标记分析及复合区间作图,检测出与抗黄萎病性相关的3个QTL,分别位于第3、5、6连锁群上,贡献率分别为14.15%、3.45%和18.78%。另外,对该群体生长过程中黄萎病不同发病高峰期的病情也进行了分析。

An intraspecific cross between Gossypium hirsutum, cv. TM-1 and G. hirsutum, cv. Changkangmian was developed for map construction. The F2 population consisting of 109 plants was cultivated at Hainan and self-pollinated. The F2：3 families were evaluated for their resistance to Verticillium wilt in an artificial pathogen garden heavily infested with an Anyang strain of V. dahliae. The 109 F2 plants and their parents were genotyped with SSR, RAPD and SRAP markers. The results showed that only 70 （pairs of） primers from 1 611 could amplify polymorphic bands and revealed 75 polymorphic loci （59 SSRs, 5 RAPDs and 11 SRAPs）. The data were analyzed using Mapmaker 3.0. Among the 75 loci, 48 loci covering 535 cM were assembled into 15 linkage groups with an average distance of 11.15 cM between markers, and 27 loci were unlinked with any locus. Based on those polymorphic loci and average disease index data of resistance to V. dahliae from F2：3 families, single marker analysis and composite interval mapping were conducted. The results showed that three markers on three linkage groups were significantly related to resistance to V. dahliae, accounting for 14. 15%, 3.45% and 18. 78% of the phenotypic variance, respectively.