洋葱种质资源遗传多样性的ISSR分析

应用ISSR标记对32份洋葱种质资源的遗传多样性进行了分析。从31个ISSR引物中筛选出4条扩增产物条带清晰、多态性高的引物,在32份资源样品中共扩增出39条带,其中31条带为多态性位点,平均每个引物扩增的多态带数为7.75条,多态性条带比率(PPB)为79.48%。资源间的遗传相似系数在0.552～0.960之间,具有较为丰富的遗传多样性。ISSR聚类分析表明,在L取值为D=0.68时,可将32份洋葱资源分成5类:第一类包括18份种质资源,主要以Yellow Sweet Spanish系统为主;第二类包括1份种质资源,为Bejo Daytona;第三类包括3份种质资源,为Yellow Globe系统;第四类包括9份种质资源,为Yellow globe danvers系统;第五类包括1份种质资源,为Yellow Danverssystem系统。较好地揭示了洋葱种质资源间的遗传多样性与亲缘关系,可为洋葱遗传育种和杂交亲本选择提供科学依据。

Genetic Diversity Analysis of Onion (Allium cepa L.) Germplasm by ISSR Markers

The genetic diversity of 32 onion (Allium cepa L.) germplasm resources were analyzed by ISSR(inter-simple sequence repeat). Four ISSR primers were screened from 31 ISSR primers. The four ISSR primers generated 39 clear bands, which 31 were polymorphic, averaged 7.75 bands each primer pair. The average percentage of polymorphic bands was 79.48 %. The genetic similarity ranged from 0.552 to 0.960, which indicated a rich genetic diversity of onion (Allium cepa L.) germplasm resources. According the result of UPGMA cluster analysis based on ISSR makers, the tested materials could be divided into five groups at the level of D=0.68. First group including 18 germplasm materials is the Yellow sweet Spanish system. Second group including one germplasm material is Bejo Dyatona cultivar. Third group including 3 germplasm materials is the Yellow Globe system. Fourth group including 9 germplasm materials is the Yellow Globe Danvers system. Fifth group including one germplasm material is the Yellow Danvers system. The results indicated that ISSR technique is useful in revealing the genetic diversity and genetic relationship among onion germplasm materials, providing a scientific basis for genetic breeding and patents selection.