甜玉米自交系遗传多样性和群体结构分析

Genetic Diversity and Population Genetic Structure Analysis of Sweet Corn Inbred Lines

本研究对141个甜玉米自交系进行遗传多样性和群体遗传结构分析,了解甜玉米的遗传基础,为提高甜玉米育种效率和种质资源利用效率提供参考。利用玉米SNP芯片进行全基因组扫描,通过使用TRUCTURE软件进行群体遗传结构分析和采用SPAGEDI软件进行亲缘关系分析,解析其群体遗传结构和遗传多样性。最终从141个甜玉米自交系中检测出16383个高质量SNP分子标记位点。基因多样性指数H为0.0595~0.4709,平均值0.3620。主等位基因频率为0.5000~0.9693,平均值0.7274。多态性信息含量(PIC)为0.0577~0.3600,平均值0.2888。46个自交系的Q值小于0.6,占总数的32.6%。群体遗传结构分析表明,Δk在k=4时达到最大值,试验材料分为4个类群,这与PHYLIP进行的聚类分析基本一致。141个甜玉米自交系整体上存在较为丰富的遗传多样性,含有4个类群,部分类群有较良好的应用潜力,亲缘关系复杂。

In this study,the genetic diversity and population genetic structure of 141 sweet corn inbred lines were analyzed to understand the genetic basis of sweet corn and provide a certain reference for improving the efficiency of sweet corn breeding and germplasm resource utilization.Using maize SNP array to scan the whole genome,the STRUCTURE software was used to analyze the population genetic structure and the SPAGEDI software was used to analyze the genetic relationship,which revealed the population genetic structure and genetic diversity.16383 high-quality SNP molecular markers were finally detected from 141 sweet maize inbred lines.The gene diversity index(H)was 0.05950~0.4709,with an average value of 0.3620.The major allele frequency value was 0.5000~0.9693,with an average value of 0.7274.The polymorphism information content(PIC)ranged from 0.0577 to 0.3600,with an average value was 0.2888.There were 46 inbred lines with Q value less than 0.6,accounting for 32.6%of the total.The results of population genetic structure analysis showed that when k=4,the Δk value reached the maximum,and the test materials were divided into four groups,which was roughly consistent with the cluster analysis performed by PHYLIP.The 141 sweet corn inbred lines had relatively rich genetic diversity on the whole,including four groups,some of which had good application potential and complicated genetic relationships.