Abstract: Genetic structure of parental inbred lines of the common maize varieties was analyzed using 56K maize gene chip,and heterosis modes of parental inbred lines of the main maize varieties were analyzed,so as to provide guidance and reference for maize breeding.The results showed that a total of 35 261 high-quality single nucleotide polymorphism(SNP) markers were obtained from 56 000 SNPs,the average of minimum allele frequency (MAF) was 0.28,the MAF of 12.56% of the SNP markers were 0.45—0.50,the polymorphism level was high.Polymorphic information content(PIC) was 0.10—0.50,with an average of 0.37.The results of cluster analysis showed that,five groups were divided,of which,group Ⅰ was mainly BSSS germplasm,which was represented by PH6WC;group Ⅱ mainly contained PH4CV,male parents of hybrid DK517 and DH605 and so on; group Ⅲ contained Reid, P group germplasm and European male parents;group Ⅳ contained domestic lines,such as Zong 3 and Zong 31;group Ⅴ contained classic SPT germplasm,Suwan and CIMMYT tropical germplasm.At the same time,the parental SNP differences of 16 maize hybrids were analyzed,and a total of 7 615 polymorphic sites and 7 592 conserved sites were selected.

Key words: Maize hybrid parent, Inbred line, Single nucleotide polymorphism, Genetic similarity, Cluster analysis, Heterosis

摘要： 基于56K玉米基因芯片对我国常用玉米骨干亲本自交系进行遗传结构解析，并对我国主推玉米品种的亲本进行杂种优势模式分析，以期为玉米育种提供指导和参考。结果表明，从56 000个单核苷酸多态性（SNP）位点中共筛选到35 261个高质量SNP标记，所检测到的最小等位基因频率（MAF）平均值为0.28，有12.56%的SNP位点处于0.45≤MAF≤0.50，具有较高的多态性水平；多态信息含量（PIC）为0.10～0.50，平均值为0.37。聚类分析结果表明，71份玉米自交系共划分为5个类群，其中，Ⅰ类群是以PH6WC为代表的坚秆综合种（BSSS）类种质；Ⅱ类群以PH4CV、迪卡517父本和登海505父本等父本自交系为主；Ⅲ类群以Reid、P群及欧洲父本自交系为主；Ⅳ类群以综3和综31为代表的国内种质为主；Ⅴ类群以SPT、Suwan及CIMMYT热带种质为主。同时，针对我国16个主推玉米品种的亲本自交系SNP差异，共筛选出7 615个多态位点和7 592个保守位点。

关键词: 玉米杂交种亲本； 自交系； 单核苷酸多态性, 遗传相似度； 聚类分析； 杂种优势