玉米单交种郑单958遗传结构及杂种优势初步研究

郑单958是我国目前推广面积最大的玉米单交种，具有高产稳产、多抗、耐密、杂种优势强等突出的优点。通过亲本郑58和昌7-2的表型特征、系谱来源、基因组的遗传结构分析，对郑单958的遗传结构及杂种优势的机理进行了初步研究。结果表明：郑58和昌7-2在的60个不同SSR位点上存在着60%的差异，其中在基因内的SSR位点上有70.6%的差异，远远高于基因组SSR位点上的差异(55.8%)。两亲本功能基因的遗传变异可能是郑单958杂种优势强的主要原因之一。

Research on the Genetic Structure and Heterosis of Zhengdan958

Zhengdan958 was a single-cross maize hybrid with high plant area in China, which characterized by high and stable yield, multi-resistant, tight plant type and high heterosis. In the study, the agronomic character, family tree and genetic structure from Zheng58 and Chang7-2 were analyzed, and the mechanism for heterosis in Zhengdan958 was also studied. The result showed that Zheng58 had 60% difference from Chang7-2 at 60 SSR loci. There were 70.6% polymorphism in gene SSR loci, and more than genome SSR loci(55.8% polymorphism). So the variance of function gene may be the one of major factor for heterosis in Zhengdan958.