黄淮海地区主要玉米自交系的SSR遗传多样性分析

利用70对SSR引物研究了我国黄淮海地区63份玉米自交系的遗传多样性。共检测出277个等位基因变异，每对引物检测等位基因2～7个，平均3.96个，每个位点的多态性信息量介于0.177～0.827，平均0.581。63份自交系之间的遗传相似系数变化范围在0.62～0.91。聚类分析表明，63份自交系被划分为4个群。在黄淮海地区利用的骨干种质为PA(Reid)、塘四平头(D)和PB(non-Reid)，杂种优势模式主要为PA×塘四平头。群内平均遗传相似系数高于群间的平均遗传相似系数，生产上主要推广杂交种的亲本自交系大多来自不同杂种优势群。提供27对区分能力强的SSR引物，用于供试自交系的快速聚类，结果与系谱来源及70对引物的聚类结果基本一致。

Genetic Diversity Revealed by SSR Markers Among Inbred Lines Used in Summer Maize Breeding Program in Huanghuaihai Area of China

Seventy SSR primers were used to detect genetic diversity among 63 inbred lines, which were widely used in summer maize breeding programs in Huanghuaihai area of China. Two hundreds and seventy-seven polymorphic fragments were detected. The average number of allele per SSR locus was 3.96 with a range from 2 to 7. The polymorphism information content(PIC) for SSR loci varied from 0.177 to 0.827 with an average of 0.581. Genetic similarity coefficient among the 63 inbred lines ranged from 0.62 to 0.91. These inbred lines could be classified into 4 distinct clusters. The dominant germplasm were PA(Reid), Sipingtou(D) and PB(non-Reid) clusters. The dominant heterotic pattern was PA×Sipingtou. Genetic similarity coefficients among clusters were higher than that within clusters. Most of the parents used in commercial hybrids came from opposite clusters or groups. Twenty-seven primers were selected from seventy SSR primers to classify inbred lines quickly. The clustering results were consistent with the clusters based on seventy SSR primers or based on the available pedigree records.