【摘要】 【目的】挖掘番茄晚疫病抗性基因紧密连锁的分子标记,为番茄抗晚疫病种质资源的利用及分子标记辅助选择育种提供理论和实践依据。【方法】利用含番茄晚疫病抗性基因ph-1,2,3的L3708(Lycopersicon.pimpinellifolium)为父本,感病的优良品系04968(L.esculentum)为母本培育的260个F2单株为图谱构建群体,通过AFLP、SSR2种分子标记进行遗传分析,构建分子遗传图谱。根据苗期接种番茄晚疫病病原菌生理小种T1,2的抗性反应,利用复合区间作图法,进行QTL定位。【结果】构建了包含12个连锁群的分子遗传图谱,其中包含3个SSR标记和149个AFLP标记。该图谱覆盖整个基因组总长度1443.07cM,平均图距9.50cM。检测到了5个与抗性基因簇ph-3相关的QTL位点,其中Qph3-1位于第3连锁群上,可以解释的表型变异为26.59%。Qph3-2位于第1染色体上,可以解释的表型变异为54.86%,Qph3-3、Qph3-4和Qph3-5,位于第9连锁群上,可以解释的表型变异分别为9.24%、10.27%和36.49%。QTL遗传效应表现为加性和显性。【结论】所得5个分子标记可作为选育抗晚疫病番茄品种的重要分子标记辅助选择工具。更多还原

【Abstract】 【Objective】 Late blight is a worldwild disease in tomato and can cause serious yield loss. Through construction of tomato molecular genetic map and QTL analysis of gene cluster ph-3 to find closely linked molecular markers. This will provide a theoretical and practical basis for molecular marker-assisted breeding. 【Method】 L3708(L. pimpinellifolium)accompanied with resistant gene cluster ph-1,2,3 was used as male parent and 04968(L. esculentum)susceptible race with good characters as female parent,the 260 F2 single plants as construction population,a molecular marker linkage map composed with 12 linkage populations was constructed by SSR and AFLP molecular marker. QTLs were found by applying complex-space mapping and according to seedling-inoculated tomato’s resistant response to Phytophthora infestans physiological stains T1,2. 【Result】 The map includes 3 SSR markers and 149 AFLP makers. And the map coveres 1 443.07 cM of the whole genome. The average space between markers was 9.50 cM. Five QTLs correlative to ph-3 were found. Qph3-1 was on the first chromosome,explainable phenotype variation was 26.59%. Qph3-2 was on the sixth linkage population and the explainable phenotype variation was 54.86%. Qph3-3,Qph3-4,Qph3-5 were on the ninth linkage population and the explainable phenotype variations were 9.24%,10.27%,and 36.49%. The genetic effect of QTL loci was additive and dominant. 【Conclusion】 The 5 QTL screened in this study can be used as a tool for molecular marker-assisted breeding.更多还原