节瓜分子遗传图谱的构建与始雌花节位性状定位

【目的】构建节瓜分子遗传图谱,标记始雌花节位性状基因,为建立相关分子标记辅助育种体系、克隆雌性相关基因和转基因提供理论依据。【方法】以节瓜全雌系K36及弱雌系G4组配得到的115个F2单株为群体,利用AFLP、RAPD和SRAP标记技术构建节瓜的分子遗传连锁图谱,并定位始雌花节位性状基因。【结果】该图谱共包含13个连锁群,涉及93个AFLP标记、16个RAPD标记、35个SRAP标记。该图谱覆盖基因组1651.9cM,标记间平均距离为11.47cM。利用QTL Network2.0分析,检测到3个控制始雌花节位的QTL位点:fn1、fn2和fn3,其中fn1位于连锁群LG1上,fn2和fn3位于LG6上。这些QTL位点对雌花节位性状表型变异的贡献率分别为62.54%、0.2%、37.39%。【结论】本研究首次构建了节瓜的分子遗传图谱,并定位了3个控制始雌花节位性状的QTL位点,为进一步克隆雌性相关基因及分子标记辅助选择育种提供科学依据。

Construction of a Molecular Genetic Linkage Map and QTL Analysis of the First Pistillate Flower Node Trait in Chieh-qua

Objective] The aims of this paper are to construct a molecular genetic linkage map and locate the first pistillate flower node traits of chieh-qua, which will provide a scientific basis for establishing molecular marker of breeding, female gene cloning and gene transfer. Method] In this study, a population of F2 generation including 115 individual plants was derived from the cross between the homozygous weak female lines G4 and the homozygous gynoecious line K36, the AFLP, RAPD and SRAP markers were used in constructing a molecular genetic map and mapping QTL traits controlling the first pistillate flower bearing node. Result] This molecular genetic linkage map included 13 linkage groups and contained 93 AFLP markers, 16 RAPD markers, 35 SRAP markers respectively. This map was 1 651.9 cM, and the average distance between two markers was 11.47 cM. Mapping of the quantitative trait loci of the first pistillate flower node was analyzed by software QTL Network 2.0, and 3 QTLs were found on the map, named asfnl,fn2,fn3.fnl located on linkage group1, fn2 andfn3 located on linkage group6. They accounted for 62.54%, 0.2%, 37.39% of the phenotypic variance, respectively. Conclusion] A genetic linkage map was firstly constructed, and three QTLs was located which control first pistillate flower node traits of chieh-qua, thus providing a scientific basis for further cloning of the female-related gene and molecular marker-assisted selection breeding.