摘要： 利用9对引物对46个品种或品系的DNA进行扩增,共得到39条多态性谱带,以相似系数和遗传距离矩阵,采用类平均法进行聚类分析,46份材料在相似系数0.33时,被分为两大类,I类为海岛棉,II类为陆地棉。II类组中陆地棉在相似系数0.568时,被分为2个亚组。亚组1为海陆杂交低代材料,具有陆地棉和海岛棉综合特征较多,从DNA扩增的谱带看,多是海陆杂合带,并有较多海岛棉带型。亚组2除品系冀031823和冀04425为纯陆地棉外,具有海岛棉优质基因的陆地棉渐渗系被分成不同的小组。扩增结果表明渐渗系主要遗传背景为陆地棉,个别性状来源于海岛棉。由于渐渗位点和基因不同,从而造成一定的差异,被聚类到不同小组。该研究为这些品系利用和新品种、杂交种培育的亲本选择提供了初步的理论依据。

关键词: 棉花, 分子标记, 遗传多样性, 聚类分析

Abstract: Genetic diversity of different cotton lines was evaluated by SSR. The genomic DNAs of 46 lines were amplified with 9 SSR primer pairs,which yielded 39 polymorphic bands. The classification of the cotton lines using the Unweighted Pair 2 group Method with Arithmetic Average based on the pair similarity coefficient,the result indicated that 46 cotton lines have been classed in 2 types,when the pair similarity coefficient was 0. 33. Type I was Sea Island cotton,and type II was upland cotton. In type II,when the pair similarity coefficient was 0. 568,upland cotton lines have been classed in 2 groups. Group I was lines with more comprehensive features of the Sea Island cotton and upland cotton. From DNA polymorphic bands,we found mostly bands of this type cotton lines were hybrid between the Sea Island cotton and upland cotton,and have some Sea Island cotton bands. In Group II,except JI031823 and JI04425 were pure upland cotton,others were introgressed lines from interspecific hybridization of G. hirsutums and G. barbadense. These introgressed lines have been classed in different sub-groups for introgressed loci were different.The study provides a preliminary theoretical foundation for the use of these lines and the parents choose for new hybrids varieties.

Key words: Cotton, Molecular marker, Genetic diversity, Cluster analysis

中图分类号: 

• S562.03