烟草糖酯SSR分子标记筛选及辅助育种应用

摘要

In order to clarify the usability of SSR molecular markers closely linked to sugar esters in the actual breeding of tobacco, and to accelerate the genetic improvement of flue-cured tobacco sugar esters, in this study, using polyacrylamide gel electrophoresis and GC-MS detection techniques, 5 tobacco germplasms with different genetic backgrounds and a genetic population with 192 recombinant inbred lines were used as experimental materials for screening and testing of 5 SSR molecular markers. The results showed that, among the 5 molecular markers, the polymorphisms of 2 molecular markers PT20315 and PT30354 were stable in different genetic backgrounds, and the correspondence between their polymorphic bands and the phenotypic difference of sugar esters were better. In the recombinant inbred line population, the consistency rate between the genotypes identified by the 2 molecular markers and phenotypes of sugar esters reached 93.75% and 90.58% respectively. The 2 molecular markers could be used in the molecular-assisted breeding of high-sugar ester tobacco. Currently, using of the 2 molecular markers in assisted selection has directionally improved new lineage materials such as high sugar ester K326 etc.%为明确与糖酯紧密连锁的 SSR 分子标记在烟草实际育种工作中的可用性,加快烤烟糖酯遗传改良进程,本研究利用聚丙烯酰胺凝胶电泳技术和GC-MS检测技术,以不同遗传背景的5个烟草种质以及192份重组自交系遗传群体为试验材料,对5个SSR分子标记开展了筛选和验证研究.结果表明,5个分子标记中,PT20315、PT30354两个分子标记在不同遗传背景中多态性稳定,并且其多态性条带与糖酯表型差异的对应性较好;在重组自交系群体中,两个分子标记鉴定的基因型与糖酯表型的一致率分别为93.75%和90.58%,可用于高糖酯烟草分子辅助育种中.目前,利用两个分子标记辅助选择,已经定向改良获得高糖酯K326等新品系材料.