利用荧光SSR分析中国糜子遗传多样性

分析糜子种质资源的遗传多样性,有助于了解糜子起源与进化,可为糜子优异种质发掘及资源高效利用提供理论基础。本研究利用15个糜子特异性荧光SSR标记检测来源于中国11个省(区)的132份糜子种质资源,检测到107个等位变异,每个位点等位变异数为2~14个,平均7个;基因多样性指数为0.0936~0.8676,平均0.5298;多态性信息含量为0.0893~0.8538,平均0.4864。采用遗传距离的聚类将试验材料分为4类,类群I来自东北春糜子区,类群II来自黄土高原春、夏糜子区,类群III来自于北方春糜子区,类群IV来自北方春糜子区和黄土高原春、夏糜子区。分析模型的遗传结构表明,中国糜子资源来自4个(东北地区、黄土高原、北方地区和西北地区)基因库,与基于遗传距离的聚类结果基本一致,均与材料的地理起源相关。糜子遗传变异丰富,主要存在于糜子材料间。该结果从分子水平上准确揭示了中国糜子的遗传多样性。

Analysis of Genetic Diversity in Common Millet (Panicum miliaceum) Using Fluorescent SSR in China

Evaluating the genetic diversity of germplasm resources in common millet is helpful to facilitate the understanding of its origin and evolution, and facilitate to explore the elite germplasm for highly effective utilization. Genetic diversity among 132 accessions of common millet from 11 provinces in China was detected by 15 millet-specific fluorescent-labelled simple sequence repeat (SSR) primers. A total of 107 alleles were detected, with alleles per locus ranging from 2 to 14 (mean = 7). Polymorphism information content and expected heterozygosity ranged from 0.0893 to 0.8538 (mean = 0.4864) and from 0.0936 to 0.8676 (mean=0.5298), respectively. Cluster analysis based on genetic distance separated the accessions into four groups, including Group I from Northeast spring-sowing ecotope, Group II from Loess Plateau spring & summer-sowing ecotope, Group III from North spring-sowing ecotope, and Group IV from North spring-sowing ecotope and Loess Plateau spring & summer-sowing ecotope. Model-based genetic structure analysis indicated that common millet accessions from China were derived from four (Northeast, Loess Plateau, North and Northwest) gene pools. The above two cluster analyses uncovered a close correlation between geographical regions and genetic diversity. There were abundant genetic variations from different accessions of common millet. The obtained information would provide an accurate estimation of the genetic diversity of common millet in China at molecular level.