水稻条斑病菌致病性效应蛋白基因差异和水稻抗病资源关系的研究

Bacterial leaf streak of rice outbreak seriously and exceed rice bacterial blight in rice production in Yunnan province. Yunnan owned abundant Xoc pathogen and rice germplasm resources. Previous studies indicated that the diversity of Xoc strains was mainly depended on the number and type of tal and xop genes. The present research will collect Xoc strains from wild rice and rice landrace varieties in Yunnan, and classify the genotypes of Xoc strains by FFLP and PCR-based analysis based on tal and xop genes, and also test pathogencity of genotype-represented Xoc strains on the typical rice varieties from Yunnan.The typical Xoc genotypes will be sellected and resuquenced,and genome-scale comparison be analyzed, further to analyze the variation of tal and xop gene structure and to mine the candidate pathogenic effector genes.And the role of typical effector genes on virulence contributions were also analyzed.We compare the difference of rice expression profiling inoculated by typical Xoc genotypes through using RAN-seq technology, and to probe the potential targets in rice manipulated by Xoc effectors. The results not only have theoretical and practical significance to reveal the genetic basis of Xoc pathogenicity, but also to search for the vertical resistant rice materials for controlling bacterial leaf streak.

水稻细菌性条斑病在云南水稻生产上危害严重，已超过白叶枯病。水稻资源及病原菌均存在丰富的多样性。前期研究发现，云南水稻条斑病菌群体多样性主要表现在tal及xop基因数量和种类上。本项目拟分离云南野生稻及地方品种上的Xoc菌株，以tal及xop基因为分析对象，划分Xoc的基因型，并在云南水稻典型代表材料上测定致病性差异；选择典型基因型的Xoc菌株，并进行基因组重测序，比较分析tal及xop基因结构变化特点，挖掘候选的效应蛋白基因，分析其在毒性变异中的作用；RNA-seq技术解析典型Xoc基因型操控水稻抗感性的表达谱差异，探究其与水稻互作中的作用靶标。研究结果不仅对揭示Xoc致病性的遗传学基础具有科学意义，而且对于发现垂直抗性的水稻材料具有实践意义。

系统利用植物病理学、分子生物学和植物生理生化相关技术开展研究，取得了主要成果如下：1）建立了利用水稻鉴别品种划分小种、tal基因分型和xop基因分型技术和Lamp检测技术，明确了我省水稻条斑病菌致病小种分化、分布和基因结构特点。利用荧光定量PCR检测tal靶标基因表达，预测云南条斑病菌含tal基因的差异；2）获得了一批广谱高抗条斑病的云南稻种资源材料43份，配制了高抗品种CG2的杂交组合，获得了F2代杂交种子；3）系统分析了抗病品种红优4号和高抗品种CG2接种3个不同tal基因型条斑病菌的转录组信息和差异基因表达特征，以及利用RT-PCR和荧光定量PCR验证获得了潜在的抗病相关基因，对条斑病菌起主动防御反应；（4）分析了高抗品种CG2 受生育期、接种方法等因素的影响，以及接种条斑病菌后胼胝质产生、激素含量、气孔变化和显微结构变化特征，基本明确了高抗品种CG2的抗性机制，为抗病品种利用控制病害提供基础；（5）共发表论文10篇，其中SCI论文2篇；申报发明专利5项，其中授权1项，受理4项；培养毕业博士、硕士共6名。