番茄疮痂病是严重影响我国露地和保护地番茄生产的一种细菌性病害，采用抗病品种是最经济有效的防治措施。但番茄疮痂病病原菌复杂，番茄材料对其抗性呈数量性状遗传，给抗病品种选育增加了难度。研究番茄对病原菌的抗性机理及分子调控机制，建立功能基因标记辅助选择体系，有利于抗性分子育种的进行。为此，本项目拟采用VIGS、瞬时表达和过表达技术对抗T3小种的候选基因Rx4进行功能验证，采用数字表达谱分析技术分离Rx4的调控基因，以及过敏反应和田间抗性的调控基因，应用TILLING技术分析抗病材料PI128216的突变体库，综合以上分析阐明番茄疮痂病菌T3小种的抗性机理及调控机制，同时建立T3小种抗性基因Rx4的功能分子标记辅助选择体系，为番茄疮痂病抗性分子育种提供理论基础。

Bacterial spot is a disease that severely affects tomato production in open and protected fields. The use of resistant varieties is an economically effective approach to control the disease. However, the pathogen causing tomato bacterial spot is complicated and the resistance to the disease in tomato is quantitatively inherited, which increase the difficulty in developing varieties with resistance to the disease. Understanding the molecular mechanism of resistance and regulation and establishing molecular markers for marker-assisted selection based on functional genes will facilitate the process of developing resistance varieties. Therefore, the project proposed here intends to use VIGS, transient expression and overexpression techniques to verify the function of the candidate gene Rx4 for resistance to race T3, to use digital expression analysis techniques to isolate genes regulating the expression of Rx4 as well as hypersensitive response and field resistance, and to use TILLING techniques to analyze the mutant populations derived from the resistance accession PI128216 for gene verification. These will allow us to illustrate the mechanism and regulation of resistance to race T3 of bacterial spot in tomato. Meanwhile, functional molecular markers will be developed for marker-assisted selection of Rx4. All results obtained in this project will provide some fundamental basis to molecular breeding for resistance to bacterial spot in tomato.