基于表型性状的陆地棉种质资源遗传多样性分析

Evaluation on Genetic Diversity of Cotton Germplasm Resources( Gossypium hirsutum L. ) on Morphological Characters

通过田间性状观测、室内考种分析及纤维品质检测,对来自我国各棉区及国外各类型的429份陆地棉优异种质进行连续2年2点15个表型性状的鉴定及综合评价。结果表明:15个表型性状中始节高、单株铃数和果枝始节位的变异系数最大;各性状的平均遗传多样性指数较高为2.02;主成分分析确立了3类影响因子,表明陆地棉品种选育应集中在纤维品质优良(尤其纤维长度和比强度要高)、高衣分和株铃数多的品种;聚类分析将所有材料分为10个类群,其中第Ⅰ类群占供试材料总数的76.9%,各类群间性状差异明显,聚类结果与材料的地理来源之间没有直接的关系。

429 superior cotton accessions from cotton regions,both in China and abroad,have been identified in2 places for 2 years. We have made a comprehensive evaluation of 15 phenotypic traits through the field observation and fiber quality testing. The results showed that the variation coefficient of height of first sympodial branch,boll number and sympodial branch node was the biggest of all traits. The average of genetic diversity index of all traits was high for 2. 02. The principal components analysis calculated three common factors in every class. The results demonstrated that upland cotton breeding should focus on the varieties,which had a good fiber quality（ the higher fiber length and strength） and a higher lint percentage and more bolls. Cluster analysis showed that all materials could be classified into 10 groups,including the first big groups accounted for 76. 9% of the total. Each group had different characteristics and showed abundant genetic diversity. There was no obvious evidence that the groups had corresponding relationship with the origins of accessions.