关键词: 建兰, 品种, SSR, 遗传多样性, 核心种质

Abstract: In this study，226 Cymbidium ensifolium cultivars were used as materials，and 16 pairs of SSR fluorescent primers were used for amplification. Based on the maximum allele method，stepwise clustering according to 11 compression ratios（93.36%，83.19%，71.68%，64.16%，54.42%，47.35%，32.30%，23.45%，17.26%，12.39%，8.41%）were performed to form alternative germplasm. The results showed that a total of 135 alleles were detected in 16 pairs of SSR fluorescent primers，the number of observed alleles（Na），the number of effective alleles（Ne），the Nei's genetic diversity index（H）and the Shannon's index（I），the observational heterozygosity（Ho），the expected heterozygosity（He）and the polymorphic information（PIC）were 8.5，3.218，0.584，1.228，0.617，0.384 and 0.539，respectively，indicating that the genetic diversity of C. ensifolium cultivars is abundant. The genetic diversity coefficients among the cultivars ranged from 0.64 to 1.0，and were classified into four categories at 0.75. The clustering results objectively reflect the genetic relationship between the cultivars. After comparing 11 candidate core collection，the 32.30% compression ratio was considered to be the optimal ratio for constructing core collections. The t-test results showed that there were no significant differences in the genetic parameters of the core collections containing 73 cultivars and the original germplasm，which could fully represent the diversity of the original germplasm.

Key words: Cymbidium ensifolium, cultivar, SSR, genetic diversity, core collection