Abstract: In order to study the genetic diversity of edible cassava in Guangxi, coefficient of variation, genetic diversity index, cluster analysis, polymorphism analysis and genetic similarity coefficient of 48 edible cassava materials were analyzed. The results showed that the average phenotypic variation coefficient of 48 accessions was 37.9%, coefficient of variation of angle of branching was the highest (86.7%); the average genetic diversity index was 0.807 and the largest diversity index character was color of root cortex (1.842). Genetic diversity was analyzed using 13 SSR molecular markers and the results showed that 118 bands were identified.Among them, 106 bands were polymorphic with of polymorphic rate of 86.23%; UPGMA clustering analysis showed that the genetic similarity coefficient among those materials ranged from 0.415 to 1.000. The phenotypic clustering and molecular clustering were inconsistent. No association was found between taxonomy and geographical origin, but there was some correlation with plant type traits. When the genetic similarity coefficient was 0.62, the materials could be clustered into two groups, the first group had irregular geographical distribution, and materials of the second group were mostly distributed in southern Guangxi. The results indicated that the genetic diversity of local edible cassava resources in Guangxi has a certain richness, which can lay a foundation for the creation of excellent edible cassava germplasm resources and the breeding of new varieties.

Key words: Guangxi, edible cassava landraces, genetic diversity

摘要： 为研究广西地方食用木薯材料的遗传多样性,以48份广西地方食用木薯为试验材料,分析其变异系数、遗传多样指数、聚类分析、多态性和遗传相似性系数。结果表明,收集的木薯材料的平均表型变异系数为37.9%,平均遗传多样性指数为0.807,其中主茎分叉角度的变异系数最大,为86.7%,块根内皮颜色的遗传多样性指数最大,为1.842。13对SSR引物共扩增出118个条带,其中多态性条带为106个,多态性比率为86.23%;分子标记聚类结果发现,遗传相似性系数在0.415~1.000之间;通过对比发现表型聚类和分子聚类结果不一致,其中表型聚类发现类群划分与地理来源之间没有关联,但与株型性状有一定的关联;在遗传相似系数为0.62时,SSR分子标记聚类为两类材料,第一类材料地理分布无规律,第二类材料大多分布在桂南。本研究结果表明,广西地方食用木薯资源遗传多样性具有一定的丰富度,可为创制优异食用木薯种质资源和新品种选育奠定基础。

关键词: 广西, 地方食用木薯, 遗传多样性