关键词: 杏, 资源, 贝叶斯聚类, 遗传多样性, SSR

Abstract: In this study，we revealed the genetic diversity and structuration of 51 apricot accessions from North and Northeast China. Bayesian clustering of these apricot accessions was addressed using 55 microsatellites that were widely distributed across the Texas × Earlygold linkage map. The most relevant levels of different genetic basis（the number of groups）were detected at K = 5，representing the highestvalue of ΔK. Thus，we proposed there were a total of five genetic basis of cultivated apricots from both North and Northeast China. The most representatives of the Northeast Chinese apricot were found in the clustering group Ⅱ and Ⅴ. Genetic diversity was estimated on these five clustering groups in term of Shannon’s index（I），which was 1.305 on average，and ranged from 1.181 in group Ⅴ to 1.568 in group Ⅳ. The Nei’s genetic distance matrix showed the highest pairwise value of 0.398 between group Ⅴ and mixture group，and the lowest pairwise value of 0.156 between group Ⅲ and group Ⅳ. The averaged pairwise Nei’s genetic distance was 0.262. Furthermore，principal coordinate analysis also showed a clear difference between group Ⅱ and Ⅴ，even there was little genetic variant among North and Northeast apricots. We selected forty-one available microsatellites and obtained a total of 140 rare alleles，with an average of 2.74 for each. The highest number of rare alleles was found in‘Limixing’accession，represented 10% total variation. However，there was no rare alleles detected in a few apricot accessions，e.g.‘Dunhulu’，‘Xinshiji’and‘Guanyinlian’

Key words: apricot, germplasm, bayesian clustering, genetic diversity, SSR