苦瓜抗白粉病基因的遗传分析及分子标记定位

Bitter gourd (Momordica charantia L.) is a major vegetable in South-China, and bitter gourd production, which most of the product is distributed to the north and northeast part of China in cool season, is an important means for farmers to increase their income in Guangxi. Powdery mildew is a major disease which causes vastly economic losses in bitter gourd production; however, breeding programs for resistant varieties are dropped behind. In this project, inheritance of bitter gourd resistant to powdery mildew will be studied. The generations of P1, P2, F1, F2 and F3 will be developed by crossing bitter gourd inbred lines of different level of powdery mildew resistance, and the distribution of resistance will be analysized using major gene and poly gene mixed inheritance model to explore the inheritance of resistance, genetic divergence, heritability and the characteristic of the resistant gene. The project also aimed development and mapping of molecular markers tightly linked to the powdery mildew resistant gene. The out put of this project will provide literature references to genetic improvement ,gene mining and plant breeding for powdery resistance in bitter gourd.

苦瓜是华南冬春蔬菜优势产区主要的外销型蔬菜品种，苦瓜生产是广西农业增效农民增收的重要途径。苦瓜的生产每年都因白粉病的发生造成大量减产，导致严重的经济损失。目前苦瓜抗白粉病育种技术水平较低，可利用的抗白粉病品种匮乏。本项目在收集到大量种质资源的基础上，开展苦瓜对白粉病抗性遗传及抗性分子机制研究。利用不同抗性资源进行杂交配组，根据P1、P2、F1、F2、F3各世代抗性水平的分布特征，用主基因—多基因混合遗传模型分析遗传分离，推断抗性基因的性质、数量及遗传效应，充分反映苦瓜对白粉病抗性的遗传规律；同时，构建苦瓜分子遗传连锁图谱，开发与抗白粉病基因紧密连锁的分子标记并将其定位到遗传图谱上；本研究的结果将为开展苦瓜抗白粉病种质创新、抗病基因挖掘和遗传改良提供理论依据。

苦瓜是华南冬春蔬菜优势产区主要的外销型蔬菜品种，苦瓜生产是广西农业增效农民增收的重要途径。苦瓜的生产每年都因白粉病的发生造成大量减产，导致严重的经济损失。目前苦瓜抗白粉病育种技术水平较低，可利用的抗白粉病品种匮乏。本项目利用一个高感白粉病资源MC18及一个高感材料MC105的F2:3 群体为材料，开发了与白粉病抗性连锁的实用性SRAP分子标记5个,SCAR分子标记1个；获得苦瓜分子遗传图谱并初步定位抗白粉病相关基因；以3对高抗白粉病亲本及高感亲本构建了3个重组自交系，已到第6代，准备下一步用于开发覆盖全基因组的SNP标记及构建SNP遗传图谱；利用不同抗性苦瓜材料为亲本组配杂交组合，并获得了P1、P2、F1、F2、F3 各世代材料，正在进行白粉病抗性鉴定，下一步将根据抗性水平的分布特征，用主基因—多基因混合遗传模型进行分析，研究苦瓜对白粉病的抗性遗传规律。本研究的结果将为开展苦瓜抗白粉病种质创新、抗病基因挖掘和遗传改良提供理论依据。