番茄抗晚疫病Ph-2基因的克隆及其功能解析

Late blight (Phytophthora infestans) is one of the major threats to tomato and potato production in the world. This pathogen can evolve rapidly thus resulted numerous isolates with varies disease spectrums. In consequence, plant resistant genes can be overcome in a relatively short period which made resistant breeding for late blight a very challenging job. However, cloning resistant genes with different mechanisms can reveal the features of late blight resistances which will provide new approaches to effectively control this disease..The interaction between plant hosts and late blight pathogen is still a puzzle, particularly, tomato-P. infestans are still poorly understood. Based on the obtained information of the tomato whole genome re-sequencing data as well as a BAC library and our acquired knowledge on fine mapping study of Ph-2 gene, this project will perform a map-based cloning approach to isolate Ph-2. VIGS and genetic transformation techniques will be combined to functional analysis the Ph-2 candidate. Phylogenetic analysis will be performed with our recently cloned Ph-3 from tomato and other cloned late blight resistance genes from potato. These results will provide scientific basis for understanding the interaction between plants and microbe pathogens especially the resistant mechanisms in tomato against P. infestans. In addition, results will be useful sources for breeding tomato with durable and board-spectrum resistance against late blight pathogens..

晚疫病（Phytophthora infestans）是危害番茄、马铃薯等作物的世界性重要病害之一，小种繁多且进化快，致使大量抗病基因在较短时间内被克服，导致抗病育种步履艰难。克隆不同类型抗病基因，可揭示其抗病机制，为病害有效防治提供新途径。.针对寄主与P. infestans互作机制尚不十分明确，而番茄与P. infestans不亲和互作知之甚少等问题。项目拟基于番茄全基因组测序和重测序结果，在精细定位的基础上，利用已构建的包含番茄抗P. infestans的Ph-2基因材料的BAC文库，结合VIGS及遗传转化手段，将抗P. infestans的Ph-2基因克隆；揭示其基因结构，分析其与项目组已克隆的抗P. infestans的番茄Ph-3及亲缘关系较近的茄科马铃薯作物基因的异同。结果将为番茄抗P. infestans育种提供直接技术支撑，为阐明寄主与病原菌共进化及互作机制提供科学依据。