中国主要黑芝麻品种的遗传多样性分析

利用SRAP和SSR各23对引物对20个中国主要黑芝麻品种进行了遗传多样性分析。结果显示,23对SRAP引物共扩增出DNA带672条,其中多态性带152条,比率为22.62%,平均每对引物扩增总带数和多态性条带分别为29.22条和6.61条。23对SSR多态性引物共扩增出DNA带92条,每对引物扩增出3~6条,平均4.00条;每对引物扩增出多态性带1~5条,平均3.09条,多态性带比率平均为77.17%。20个黑芝麻品种间的遗传相似系数为0.8547~0.9804,遗传距离为0.0159~0.0921,遗传多样性匮乏,遗传基础狭窄。聚类结果表明,来自主产区江西的11个品种明显聚在一起,且江西黑芝麻品种的遗传相似系数高于其他省份品种,遗传距离低于其他省份品种,与其他省份品种的差异均达到极显著水平。加强资源引进和利用是拓宽中国黑芝麻品种遗传基础的迫切要求。

Analysis of Genetic Diversity of Main Black Sesame Cultivars Released in China

SRAP and SSR analysis were performed on 20 main black sesame cultivars released in China with 23 pairs of primers for analyzing genetic diversity. The results showed that: A total of 672 DNA bands were amplified by 23 pairs of SRAP primers, with 152 of them were polymorphic, resulting polymorphic ratio of 22.26%, and the total and polymorphic bands amplified by every primer pair averaged 29.21 and 6.61, respectively. In SSR, 92 DNA bands were amplified by 23 polymorphic primer pairs, each primer amplified 3-6 total bands and 1-5 polymorphic bands, the average was 4.00 and 3.09, respectively, and the degree of polymorphic bands was 77.17% averagely. Genetic similarity and genetic distance of 20 black sesame cultivars were 0.8547-0.9804 and 0.0159-0.0921, indicating limited genetic diversity and narrow genetic basis. The clustering results showed that 11 cultivars from main producing area Jiangxi were obviously clustered together, and the genetic similarity of Jiangxi black sesame cultivars was higher than that of the cultivars in other provinces, with the genetic distance lower than other province and the differences of them all reached a very significant level. Strengthening the introduction and utilization of germplasm is an urgent need for broadening the genetic basis of black sesame cultivars in China.