木豆种质资源AFLP标记遗传多样性分析

利用AFLP分子标记技术，以木豆野生种(Cajanus scarabaeiodes)为对照，对来自印度、中国、非洲和美洲的139份栽培木豆(Cajanus cajan)种质遗传多样性进行研究。17对引物共扩增出502条清晰可辨的带，其中多态性带494条。遗传相似性系数UPGMA聚类图，揭示木豆种内存在足够的遗传多样性，可用于种质资源的准确鉴别与分类。借助遗传距离的ME进化树又将参试种质分成8个组群。分析结果表明，印度地方资源遗传多样性广泛，育成品种遗传基础广阔；非洲、美洲资源遗传多样性较丰富，且与印度资源的亲缘关系较密切。中国地方资源遗传多样性独特，且与印度、非洲、美洲栽培木豆资源亲缘关系不明显。研究结果基本支持印度木豆起源和多样性中心、非洲次生多样性中心的观点，并提出中国次生起源中心和遗传多样性中心假说。研究还发现，木豆核质互作雄性不育系(A)和保持系(B)间存在独特的AFLP谱带差异，可能有助于分子标记辅助的木豆杂种优势利用和杂交种培育。

Genetic Diversity Analysis of Pigeonpea Germplasm Resources by AFLP

China is rich in indigenous pigeonpea genetic resources in Yunnan, Guangxi and their nearby provinces.Morphologically and ecologically,Chinese local pigeonpea genetic resources differ greatly from those of Indian originated accessions.The research was designed mainly to answer the questions on how different between pigeonpea genetic resources of Chinese origin and of foreign origin, by genetic diversity analysis from DNA level.The results will help to guide the genetic resource collecting,research and breeding programs of pigeonpea in China and abroad.In the research,a representative set of 139 pigeonpea genetic resources from India,China,Africa and Latin America,together with a wild pigeonpea(Cajanus scarabaeiodes) accession as check,were analyzed by AFLP methodology using 17 informative primer pairs.In total,502 unambiguous bands were detected, of which 494 were polymorphic.According to the dendrogram by UPGMA cluster analysis,almost all the accessions were distinct and revealed enough genetic diversity for identification and classification of accessions within Cajanus cajan.Using genetic distance matrix,by ME cluster analysis from MEGA 3 statistical package,eight distinct evolutionary groups were detected.According to the study on the eight evolutionary groups,Indian local pigeonpea resources held broad genetic diversity,followed by those from Africa and America with close consanguineous relationships to Indian local accessions.The preliminary results indicated Chinese indigenous pigeonpea resources held unique characteristic on their genetic diversity,with less consanguineous relationships to Indian,African and American local accessions.The preliminary results partly support the traditional theory on "India is the center for pigeonpea origin and genetic diversity,Africa is the sub-center on genetic diversity of pigeonpea".But,China may be another sub-center for origin and genetic diversity of pigeonpea,according to the study.Distinct AFLP bands between sterile line(A line) and maintainer line(B line) of pigeonpea CMS system were detected,which may potentially use for marker assisted hybrid breeding program in pigeonpea.