广西地方稻种资源核心种质构建和遗传多样性分析

以丁颖分类体系分组原则与组内逐层聚类取样方法,对8609份广西地方栽培稻资源表型数据信息进行分析,通过对表型保留比例等评价指标的多重比较确定核心种质总体取样比例,构建出占总体样本5%(414份)的广西地方栽培稻资源初级核心种质。初级核心种质能代表总体遗传变异的89%。用34对SSR分子标记对初级核心种质进行遗传多样性分析,结果表明:广西地方栽培稻资源有较高的遗传多样性(等位基因数A为4.91,Nei’s多样性指数为0.574)。就Nei’s遗传多样性指数而言,粳稻高于籼稻,晚稻高于早稻,水稻高于陆稻,糯稻高于粘稻;来自桂中的稻种资源具有最高的遗传多样性。研究最终利用SSR数据,把414份初级核心种质压缩50%后形成209份核心种质,核心种质基因保留比例达到98%以上,有效代表了广西地方栽培稻资源多样性水平。

Construction of core collection and genetic diversity of landrace rice resources (Oryza sativa) in Guangxi

A primary core collection of rice germplasm consisting of 414 accessions(ca.5%) was constructed from a total of 8 609 accessions of Guangxi landrace rice by analyzing their taxonomic,morphological and yield characters,grouping based on Dingying’s taxonomic system,clustering within groups,and selecting optimal total sampling proportion through comparing the three detection parameters and four evaluation index.This collection represented 89% of the total genetic variation.Genetic diversity of the primary core collection was estimated by using 34 SSR primers,and showed that Guangxi landrace rice resources were highly genetically diverse with average effective numbers of alleles(Ae) reaching 4.91 and average Nei’s genetic diversity index(H) reaching 0.574.The Japonica group had higher H value than Indica group,late rice had higher H value than early rice,lowland rice had higher H value than upland rice,and glutinous rice had higher H value than non-glutinous rice,The central Guangxi rice ecological region had the highest genetic diversity.Based on the SSR data,414 primary core collections could further be condensed to 209 core collections,which has a genetic reservation proportion higher than 98%,and thus had good representation of genetic diversity of Guangxi landrace rice.