我国棉花抗枯、黄萎病骨干品种(系)基于AFLP的遗传多样性

Genetic Diversity of Chinese Key Cottons with Fusarium and Verticillium Wilts Resistance Based upon AFLPs

利用AFLP分子标记技术,对我国20世纪50年代开展抗枯、黄萎病育种以来培育的105份骨干品种(系)的遗传多样性进行了研究。结果表明,筛选的20个AFLP引物组合在该品种群体中扩增了1498个AFLP标记,其中多态性标记232个,占总标记数的15.5%。单一引物组合扩增的DNA标记数变化在49111之间,平均每个引物组合扩增的总标记和多态性标记分别为74.9和11.6。在该抗病品种群体中,有46个品种(系)具有特异标记,占品种总数的43.81%,其中引物组合E41/M50可使10个品种产生特异标记。品种(系)之间的成对欧氏距离总平均值为4.353,变幅为1.7326.708,单一品种欧氏距离平均值变幅为3.5315.705,高于总平均值的品种数不足50%,表明该陆地棉抗病品种群体的遗传多样性较低。基于AFLPs多态性数据的聚类分析,105个品种(系)被划分为5个陆地棉品种类群(Uplandcottongroups,UCGs),每个UCG包含的品种数目不同。

Genetic diversity of 105 Chinese key cottons with Fusarium and Verticillium wilts resistance was studied based on AFLP markers. Twenty primer combinations were selected to perform the AFLP fingerprinting from 100 primer combinations. A total of 1498 DNA fragments were scored among all materials, averaging 74.9 for each primer combination, of which, 232 ((15.5%)) bands were polymorphic. The number of DNA bands per primer combination ranged from 49 to 111, with the average of 11.6 polymorphic markers. Forty-six cultivars, as much as 43.81% of the 105 materials, had specific bands. The primer combination, E41/M50, made 10 materials produce specific markers. Mean pairwise genetic distance of 105 cultivars (lines) was 4.353,with the range of 1.732 to (6.708.) Range of mean genetic distance for each variety was 3.531~5.705. Less than 50% of materials were below mean genetic distance. The limited genetic diversity was revealed by these results in the population. Based on dendrogram of AFLPs, 105 cultivars (lines) were classified into five upland cotton groups (UCGs). The number of cottons was different in each UCGs, and their geographic origins and descents were diverse.