Genetic Analysis And Rough Mapping Of Maize Male Sterile Mutant

Male sterility is a common biological phenomenon and is a crucial approach for heterosis utilization. In this study, we screened a maize MU9mutant library and identified a maize male sterile mutant(named L11467S). Then we conducted the phenotype analysis, genetics study and mapping, and the main results are as follows:1、We found a sterile segregate line from the M2generation of MU9mutant library, which had9fertile plants and3sterile plants, and after analysis of multiple generations, we confirm that the sterility is a steady heritable character.2、Phenotype analysis indicated that there was no difference between the wild-type and mutant in the vegetative stage, but during the anthesis, we found the defects in the anther dehiscence, leading to the failure of anther release from lemma and palea and pollination. Compared with the wild type, the mutant anthers were smaller and brown.But female sterility was not affected.3、We crossed the mutant with inbred line B73, MO17, Zheng58and C7-2respectively, and observed the phenotype of the progeny F1and F2and made a statistic analysis, the result indicated that the sterility phenotype was controlled by a single recessive gene.4、To identify the mutant gene, we used a map-based cloning approach. We got31pairs of polymorphic SSR primers between mutant and inbred line Zheng58from135pairs of primers of the whole genome, and then located this gene on the chromosome1after testing the Zheng58-F2mapping population, which contained46fertile plants and29sterile plants. Then we verified this gene was mapped on chromosome1with the MO17-F2mapping population, which had71sterile plants. Finally, with the488male sterile individuals of Zheng-58F2mapping population, we mapped this gene on the chromosome1between SSR marker211513-8and SSR marker208984-2, the physical gap of them is about1.4MB.