水稻抗病基因和稻瘟病菌无毒基因的相互作用，符合经典的“基因对基因”关系，抗病基因和无毒基因长期相互作用中，水稻和稻瘟病菌表现出繁荣-衰败（Boom-Bust）循环之寄主和病原物共同进化的特点。在抗病基因的选择压力下，稻瘟病菌的无毒基因容易发生结构变异导致功能丧失，无毒基因功能丧失后的稻瘟病菌群体在不断适应新环境中是否分化出新的分化位点值得探讨。本项目拟在我们克隆了稻瘟病菌无毒基因AVRPiz-t及自然群体中AVRPiz-t变异特点基础上，采用基于群体基因组混合池测序和全基因组关联分析方法在稻瘟病菌自然群体、历史群体、人工群体中，研究在无毒基因AVRPiz-t变异后稻瘟病菌群体在不断适应新环境中毒性增强的分子机制，分析潜在强烈分化位点，分析群体中可能获得的新的效应因子，为揭示无毒基因与抗病基因互作过程中病原菌基因组适应新环境微进化的规律奠定基础，还可以为制定稻瘟病可持续治理策略提供理论依据。

It is well known that interaction of resistance gene in rice and avirulence gene in Magnaporthe orayze follows the gene foe gene theory. With the long term R- avirulence gene interaction, rice blast disease epidemics shows as boom-bust cycle through host and pathogens coevolution. In general, it is easy to understand that with high selective pressure from host R gene the avirulence gene will be under a frequent structural variation leading to loss of avirulence function. However it is really difficult but worth to study the mechanism of how the rice blast pathogen can adapt to newly developed environment niche with the non-functional avirulence gene. In our case, on the basis of our previous cloned AvrPiz-t and AvrPiz-t mutantion survey project, we will conduct a combined genome DNA Pool-sequencing and genome-wide association study with the natural, historical and artificial population of rice blast fungus to fine-map the positive selection candidates, selective sweep region or newly-gained putative effector proteins at the whole genome level. Furthermore we will try to interpret the molecular adaptation mechanism why AvrPizt(-) rice blast pathogen can gain constitutive virulence in new environment. Our research proposal will intend to uncover the genome microevolution of the fungal pathogen during the new developed environment and provide new theory to designa better and suswtainable strategy to manage the rice blast disease.