摘要
采用SSR分子标记技术对50份不同来源的籽用西瓜材料进行遗传多样性研究,并基于SSR分子标记聚类分析采用最小距离逐步抽样法构建籽瓜初级核心种质库。研究表明:(1)从106对SSR随机引物中筛选出扩增条带清晰、多态性高的31对引物,共得到138条清晰可辨条带,其中多态性条带115条,占83.33%,平均Shannon’s信息指数(I)为0.419 3,平均Nei’s多样指数(h)为0.272 4,平均有效等位基因数(Ne)为1.458 0,平均等位基因数(Na)为1.981 4,说明50份籽瓜种质具有丰富的遗传多样性。(2)用NTsys2.10e软件对种质资源聚类分析表明,种质间的遗传相似系数介于0.57~0.91之间,其中来源地相同的个别种质间遗传相似系数却很小,而来源地不同的个别种质间的遗传相似系数却很高。(3)采用最小距离逐步抽样法,按70%、60%、50%、40%、30%、20%、10%的比例抽样后,各个核心子集遗传多样性指数总体上变化不明显,但各抽样比例相比,以抽样比例20%获得10份初选种质的Ne、h和I达到最高值,说明抽样20%构建的初级核心种质对原始种质具有很好的代表性。
The genetic diversity of 50 seed watermelon germplasm from different places were analyzed by SSR molecular marker and the primary core collection was constructed by Least Distance Step-wise Sampling(LDSS).The results showed that:(1)31pairs of primers which showed high polymorphism were selected from 106 SSR primers,showed 115 polymorphic bands in 138 bands owning 83.33% polymorphic loci,the average of Shannon information index(I),Nei's genetic diversity(h),effective number of alleles(Ne)and number of alleles(Na)by POPGENE32 analysis was 0.419 3,0.272 4,1.458 0and 1.981 4,respectively,which indicated high genetic diversity in 50 seed watermelon accessions.(2)The clustering result showed that genetic similarity coefficient ranged 0.57-0.91.Some germplasms distributed in different origins and far geographic distance showed high genetic similarity coefficient in 50 accessions.(3)The germplasm were sampled by the method of LDSS and ratio at 70%,60%,50%,40%,30%,20% and10%,and the genetic diversity parameters of each core subset was compared.The results showed that the change of genetic diversity parameters of each core subset was not clear with the samples reduced in six samplings.But the percentage of polymorphic loci,Ne,hand I of 10 primary accessions were obtained by sampling proportion 20%.It showed that the primary core collection from 20%sampling could well represent the genetic diversities of the whole collection.
出处
《西北植物学报》
CAS
CSCD
北大核心
2016年第6期1125-1134,共10页
Acta Botanica Boreali-Occidentalia Sinica
基金
内蒙古自然科学基金(2016MS0356)
内蒙古科技计划(20090707,2010704,20110711,20120212)
内蒙古高寒地区高产安全蔬菜生产的研究与创新(NDPYTD2013-3)
关键词
籽用西瓜
SSR分子标记
种质资源
遗传多样性
核心种质
seed watermelon
SSR molecular marker
germplasm resources
genetic diversity
core collection