马铃薯品种遗传多样性分析

为解析一套(559份)从世界各国收集的马铃薯种质资源的遗传多样性,用16个表型性状和36个SSR标记进行了聚类和多样性参数分析。对454份表型数据完整材料的UPGMA聚类分析表明,在欧氏距离14.66处被聚成2个类群(A_1和A),其中A_1在欧氏距离12.74处被分为A_(11)和A_(12)亚群;454份材料在欧氏距离11.73处被划成9个类群,包括4个小类(A、B、C和H)和5个大类(D、E、F、G和I),其中类群I所包括的材料占总数的57.5%,该结果较好地揭示了马铃薯种质材料之间的形态差异,区分生态类型不同和遗传差异明显的亲本。36个SSR标记在559份材料中共检测出134个多态性位点,每对引物检测1~7个等位变异,平均3.72个,引物多态性信息量(PIC)为0.1545~0.7743,平均为0.5783,说明品种间有丰富的遗传多样性。NJ系统进化树分析表明,559份材料可分为3个大群。类群I为一个混合群,各地区品种均有分布,包括133份马铃薯材料,占总数的23.8%;类群II中欧洲、北美及中国东北和西北地区的材料所占比重较大,数量为187,占33.5%;类群III中北美、南美以及中国东北和西南地区马铃薯材料所占比重较大,包含239份材料,占42.8%。表型性状聚类与SSR分子标记聚类结果相似,均与地理位置有很大相关性,应结合共同用于评价马铃薯品种遗传多样性。

Genetic Diversity Analysis of Potato varieties

Based on the 16 phenotype traits, we performed UPGMA cluster analysis for 454 potato accessions. All the accessions were grouped into two clusters A1 and A at the Euclidean distance of 14.66. The cluster A1 was further grouped into two subclusters A11 and A12 at the Euclidean distance of 12.74. All the accessions were grouped into nine clusters (A, B, C, H, D, E, F, G, and I) at the Euclidean distance of 11.73, and the cluster I was the biggest group, accounting for 57.5% of all the accessions. The cluster analysis more accurately revealed the morphological difference among potato materials, and distinguished the parental materials with different ecological types and genetic differences. Meanwhile, the genetic diversity of 559 potato accessions from worldwide was analyzed with 36 pairs of SSR primers. A total of 134 polymorphic alleles were amplified. Polymorphic alleles were amplified by each pair of primer ranging from one to seven, with a mean of 3.72. The fragment size amplified varied from 106 to 308 bp. The polymorphic information content values (PIC) were from 0.1545 to 0.7743 with a mean of 0.5783, which indicated SSR markers can reflect more abundant genetic diversity information in potato varieties. The further phylogenetic tree analysis showed that all 559 accessions were clustered into three groups. Group I was a mixed one, containing 133 (23.8%) materials from almost all regions. Group II was one mostly gathered by accessions from Europe, North America, Northeast and Northwest regions in China. There were 187 materials in this group, accounting for 33.5% of all. Group III consisted of 239 accessions (42.8%), mainly distributing in North America, South America, Northeast and Southwest regions in China. The clustering results based on phenotypic traits were similar to those based on SSR markers, both highly relating to geographic location, indicating that both method should be combined to use in potato genetic polymorphism evaluation.