中国花生小核心种质与ICRISAT微核心种质的SSR遗传多样性比较

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。

Comparison of Genetic Diversity between Peanut Mini Core Collections from China and ICRISAT by SSR Markers

A core collection or mini core is a subset of accessions from the entire collection that covers most of available genetic diversity of a species. Extensive investigation of core collections is an efficient approach to enhance evaluation and utilization for crop germplasm. The mini core collections of peanut (Arachis hypogaea L.) from China consisting of 298 accessions and from International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) consisting of 168 accessions were comparatively analysed by SSR method. Twenty six polymorphic SSR markers screened from 206 primer pairs were used to investigate the similarity and genetic distance among the peanut accessions involved. The similarity coefficients between the genotype pairs among the 466 accessions ranged from 0.49 to 0.99. The largest genetic distance was between L2 Gangguo (a Chinese genotype) and ICG12625 (an ICRISAT genotype) with a similarity coefficient of 0.49. Among the six botanical types in peanut, accessions of fastigiata and hypogaea were more diversified than other types. There was considerable genetic difference between the Chinese peanut accessions and some ICRISAT accessions especially with the aequatoriana genotype ICG12625. The genetic diversity was greater among the Chinese peanut mini core than that among ICRISAT mini core in terms of the similarity coefficient and genetic diversity index.