广东甘蔗品种遗传多样性的AFLP分析

AFLP Analysis of Genetic Diversity in Sugarcane Varieties in Guangdong Province

采用15对多态性较好的AFLP引物对广东育成的41个甘蔗品种的遗传多样性进行分析。结果表明:每对引物的多态性位点平均为61.5,多态性位点百分率为77.40%。41个甘蔗品种间的遗传相似系数为0.5210～0.9211,平均为0.6842,遗传多样性属中等水平。聚类分析把41个品种分为2大类,在系谱中亲缘关系密切的大多数品种,如粤农81-762与粤农85-1285和粤农86-295,粤糖57-423与粤糖85-5和粤糖85-177等都能分别聚在一起。但也有例外,如粤糖83-251和粤糖83-271,都是CP72-1210×华南56-12组合的后代,但没有归为同一类。遗传多样性指数分析显示,不同年代的品种多样性指数差异明显,最高是80年代,为0.3072,最低是60年代,为0.1162;不同单位选育的品种遗传多样性指数变化不大,为0.2756～0.3061。加强新种质利用是有效提高甘蔗品种遗传多样性的重要措施。

The genetic diversity of 41 sugarcane varieties bred in Guangdong Province was studied using 15 AFLP primer pairs. The results showed that the average polymorphic loci per primer pair were 61.5, and the percentage of polymorphism loci was 77.40%. The genetic similarity indexes of 41 varieties ranged from 0.5210 to 0.9211, with an average of 0.6842, which implied that the genetic diversity among the varieties was at middle level. The 41 varieties were clustered into two groups. Most of the varieties with close relationship in family-tree could be clustered into the same groups, such as YN81-762, YN85-1285 and YN86-295, as well as YT57-423, YT85-5 and YT85-177, but some varieties could not, such as YT83-251and YT83-271 which derived from the same cross ＂CP72-1210 × Huanan 56-12 ＂ The varieties selected at different periods showed remarkable differences in genetic diversity index （GDI）. The varieties selected in 1980s were found to be the highest （GDI = 0.3072）, and the 1960s the lowest （GDI =0.1162）. GDI of varieties from different Institutes revealed a little bit difference, but still kept in unremarkable level （from 0.2756 to 0.3061）. The result indicated the genetic diversity would be increased by using new sources from sugarcane germplasm.