甜瓜种质资源遗传多样性分析与核心种质构建  

Genetic diversity analysis of melon germplasm resources and construction of the core germplasm

作　　者：卿东山 何长征[1,2,3] 罗玉松 宋慧娟 蔡雁平 孙小武[1,2,3] 戴思慧 QING Dongshan;HE Changzheng;LUO Yusong;SONG Huijuan;CAI Yanping;SUN Xiaowu;DAI Sihui(College of Horticulture,Hunan Agricultural University,Changsha,Hunan 410128,China;Laboratory of Yuelushan,Changsha,Hunan 410128,China;Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding,Ministy of Education,Changsha,Hunan 410128,China)

机构地区：[1]湖南农业大学园艺学院,湖南长沙410128 [2]岳麓山实验室,湖南长沙410128 [3]园艺作物种质创新与新品种选育教育部工程研究中心,湖南长沙410128

出　　处：《湖南农业大学学报(自然科学版)》2025年第2期36-43,共8页Journal of Hunan Agricultural University(Natural Sciences)

基　　金：国家西甜瓜产业技术体系项目(CARS–25)。

摘　　要：以200份甜瓜种质为研究对象,利用SSR分子标记数据进行遗传多样性分析,并依据遗传相似性系数逐步进行聚类分析,多次抽样构建甜瓜核心种质库。结果显示:35对SSR标记共扩增出109个多态性位点,平均等位基因数(Na)、有效等位基因数(Ne)、观测杂合度(Ho)、期望杂合度(He)、多态性信息含量(PIC)、香农指数(I)分别为3.11、2.60、0.37、0.57、0.49、0.96;利用非加权配对算术平均法(UPGMA)进行聚类分析,可将200份种质分为2大类;遗传结构分析结果表明,当群体数K=2时,最佳群体分层情况Δk最大,供试种质可划分为2个亚群,符合聚类结果;构建的各核心子集遗传多样性指数总体上变化不明显,最终确立了10.0%的取样比例,包含20个甜瓜品种核心种质,其中Na的保留率为98.17%,Ne的保留率为99.42%,I的保留率为99.79%,Ho的保留率高达104.08%,He的保留率为100.35%,PIC的保留率为99.59%;t检验和主坐标分析结果表明核心种质和原始种质的遗传多样性参数无显著差异,能充分代表原始种质的遗传多样性。With 200 melon germplasm as the research object,SSR molecular marker data were used for genetic diversity analysis,and stepwise unweighted pairwise arithmetic mean(UPGMA)clustering was performed on the genetic similarity coefficients,and multiple sampling was used to construct a core germplasm library of melon.The results showed that a total of 109 polymorphic loci were amplified by 35 pairs of SSR markers,the average number of alleles(Na),the number of effective alleles(Ne),the observed heterozygosity(Ho),the expected heterozygosity(He),polymorphism information content(PIC),and the Shannon index(I)were 3.11,2.60,0.37,0.57,0.49,0.96,respectively.Cluster analysis based on UPGMA categorized the 200 germplasm into 2 major groups.Genetic structure analysis showed thatΔk was the largest when K=2,and the tested germplasm could be divided into 2 subgroups,which was consistent with the clustering results.The genetic diversity indices of each core subset constructed did not change significantly in general,and a sampling ratio of 10.0%was finally established,containing 20 core germplasm of melon varieties(species),of which the Na retention rate was 98.17%,the Ne retention rate was 99.42%,the I retention rate was 99.79%,the Ho retention rate was as high as 104.08%,the He retention rate was 100.35%and the PIC retention was 99.59%.The t-test and principal coordinate analysis showed that there was no significant difference between the genetic diversity parameters of the core germplasm and the original germplasm,and the genetic diversity of the original germplasm could be adequately represented.

关 键 词：甜瓜 SSR标记 遗传多样性 核心种质 

分 类 号：S652[农业科学—果树学]