基于TP-M13-SSR分子标记技术的133份薄皮甜瓜种质资源遗传多样性分析

Genetic diversity analysis of 133 pellicle melon germplasm resources based on TP-M13-SSR molecular marker technology

  • 摘要: 【目的】分析我国不同省(区)的薄皮甜瓜种质资源遗传多样性,为今后薄皮甜瓜的种质资源收集及遗传改良和高效利用提供理论依据。【方法】以来自我国不同省(区)的133份薄皮甜瓜种质为材料,从98对SSR引物中筛选得到12对多态性较高的引物,利用TP-M13-SSR分子标记技术对133份薄皮甜瓜种质材料进行遗传多样性分析,并根据Nei’s遗传距离(D)进行聚类分析,以Structure软件的混合模型聚类法分析其群体遗传结构。【结果】利用12对引物从133份薄皮甜瓜种质材料中共扩增出的等位基因数(Na)为54个,平均每对引物4.5个,有效等位基因数(Ne)为1.120~2.234,平均为1.533;观测杂合度(Ho)为0.023~0.466,平均为0.217;期望杂合度(He)为0.107~0.552,平均为0.319,香农信息指数(I)范围为0.267~1.237,平均为0.642;各位点的多态性信息含量(PIC)为0.104~0.531,平均为0.295,大多数位点表现为中度多态性。聚类分析结果显示,133份薄皮甜瓜种质材料被分为两大类群,第Ⅰ类群为4份厚薄皮甜瓜材料,第Ⅱ类群为129份薄皮甜瓜材料。群体遗传结构分析结果显示,当K=4时,△K出现明显的峰值,说明133份薄皮甜瓜种质材料分为4个组群较合适;133份材料中大部分材料的Q值大于0.6。【结论】供试的12对SSR引物表现为中度多态性,需要用更多的分子标记才能有效鉴别薄皮甜瓜材料。133份薄皮甜瓜种质材料遗传结构较为单一,遗传多样性较低,可能存在同物异名的材料,今后应加强对遗传背景差异大、亲缘关系远的种质资源的发掘利用。

     

    Abstract: 【Objective】To analyze genetic diversity of pellicle melon germplasm resources from different provinces(regions)in China,so as to provide theoretical basis for collection,genetic improvement and efficient utilization of melon germplasm resources.【Method】133 samples of pellicle melon germplasms from different provinces(regions)in China were taken as materials. 12 pairs of SSR primers with high polymorphism were screened. Genetic diversity analysis of 133samples of pellicle melon germplasm materials was conducted through TP-M13-SSR molecular marker technology. Cluster analysis model was performed according to the Nei's genetic distance(D)and the genetic structure of population material was analyzed by the mixed model clustering method of Structure software.【Result】The number of alleles(Na)was54 after amplification of 133 samples of pellicle melon germplasm materials with 12 pairs of primers and the average Na per pair of primers was 4.5. The number of effective alleles(Ne)was 1.120-2.234,and the average was 1.533. Observed heterozygosity(Ho)was 0.023-0.466,with an average of 0.217. Expected heterozygosity(He)was 0.107-0.552,with an average of 0.319. The Shannon information index(I)ranged from 0.267-1.237 with an average of 0.642. Polymorphism information content(PIC)of sites ranged from 0.104-0.531,with an average of 0.295,indicating most sites were moderately polymorphic. According to cluster analysis,133 pellicle melon materials were divided into two groups. GroupⅠ consisted of 4 thick and thin skinned intermediate melon materials,and group Ⅱ consisted of 129 pellicle melon materials.According to results of population genetic structure analysis,when the K=4,△K peaked obviously,indicating that the 133sample shall be divided into 4 groups. Moreover,among 133 materials,the Q value of most materials was greater than 0.6.【Conclusion】The 12 pairs of primers used in this study are moderately polymorphic,and more molecular markers are needed to identify pellicle melon materials effectively. The genetic structure of the tested materials was relatively simple and of low genetic diversity,indicating identical materials with different names may exist. Exploration and utilization of germplasm resources with different genetic backgrounds and distant relationships should be strengthened.

     

/

返回文章
返回