Comparison of Genetic Diversity Based on SSR Markers Between Peanut Mini Core Collections from China and ICRISAT

Mini core collection plays an important role in evaluating genetic resources of peanut (Arachis hypogaea L.). This study aimed at comparing the genetic diversities of a domestic and exotic peanut mini core collections and providing basic data for germplasm introduction and peanut breeding. The exotic mini core collection, which was introduced from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT, Patancheru, India), consisted of 168 accessions, whereas the Chinese mini core collection consisted of 298 accessions. A total of 26 polymorphic simple sequence repeat (SSR) markers were used to evaluate the genetic diversity of these genotypes and their similarities. The similarity coefficient ranged from 0.49 to 0.99 among the total 466 accessions and the largest genetic distance was between “L2 Gangguo” from the Chinese core collection and “ICG12625” from the ICRISAT core collection. Among the 6 botanical types of peanut, the fastigiata type had the largest genetic diversity indices in both Chinese and ICRISAT mini core collections, which were 1.11 and 0.97, respectively. The hypogaea type had the second largest diversity with genetic diversity indices of 0.89 and 0.88 for Chinese and ICRISAT mini core collections, respectively. The genetic distance between the 2 mini core collections was larger than that within a mini core collection. Particularly, the aequatoriana genotype ICG12625 from ICRISAT had the largest differences to the Chinese genotypes. According to similarity coefficient and genetic diversity index, the genetic diversity was greater among genotypes from the Chinese mini core collection than that from the ICRISAT mini core collection.

摘 要明确花生种质资源的遗传多样性和分布规律, 对于发掘优良种质资源, 选配优良亲本, 拓宽育成品种的遗传基础具有重要意义。核心种质为种质资源的研究、评价和鉴定带来了方便。本研究从206对SSR引物中筛选26对引物对我国花生小核心种质和ICRISAT微核心种质共466份资源进行了遗传多样性分析, 相似系数为0.49∼0.99, 鉴定出遗传差异最大的种质L2刚果(中国花生资源)与ICG12625(ICRISAT资源), 相似系数为0.49。分析结果表明, 多粒型花生的多态性信息量(0.761)和遗传多样性指数(0.97∼1.11)均最大(平均相似系数最小, 0.73∼0.76), 其次是普通型花生。中国花生种质资源与ICRISAT资源存在较大差异, 尤其是ICRISAT的赤道型材料ICG12625, 与中国花生资源的差异最大。相似系数和遗传多样性指数的分析结果均表明, 我国花生种质资源的遗传多样性比ICRISAT资源丰富。