Genetic diversity,population structure,and botanical variety of 320 global peanut accessions revealed through tunable genotyping-by-sequencing

【摘要】：To reveal the evolutionary relationships among different botanical varieties of Arachis hypogaea L.,320 peanut accessions were collected,including landraces and breeding lines worldwide.A total of 37 128 high-quality single nucleotide polymorphisms(SNPs) were selected from 1 240 787 potential polymorphic sites detected by tunable genotyping-by-sequencing.Aphylogenetic tree indicated that the tested accessions were grouped into3 clusters.Almost all of peanut accessions in cluster C1 were var.fastigiata.Meanwhile,clusters C2 and C3 mainly consisted of var.vulgaris and subsp.hypogaea,respectively.Results of principal component analysis were consistent with relationships indicated by phylogenetic tree.Population structure analysis revealed that var.fastigiata and var.vulgaris were not separated when K = 2(subgroup number),whereas they were clearly divided when K =3.Fixation index(F_(ST)) value confirmed that var.fastigiata was closely related to var.vulgaris(F_(ST_)=0.284),while var.hypogaea was clearly distinct from other 2 botanicalvarieties(F_(ST) 0.4).Moreover,nucleotide diversity(π) value implied that var.vulgaris exhibited the highest genetic diversity(0.048),followed by var.fastigiata(0.035) and var.hypogaea(0.012).Furthermore,the reliable SNPs identified in this study may be a valuable resource for peanut breeders.