Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China.
Phytopathology. 2019 Aug;109(8):1433-1440. doi: 10.1094/PHYTO-10-18-0383-R. Epub 2019 Jul 5.
and . are important agents of major diseases on a wide range of gramineous hosts. Whereas . is the most important pathogen causing outbreaks of rice blast, . is mainly a pathogen of crabgrass. In this study, 103 and 20 isolates were collected from seven species of plants, and we analyzed their phylogeny, pathogenicity, and relationship with host preferences to investigate the differences among them from different hosts. Based on phylogenetic analysis of multilocus sequences, 16 isolates from crabgrass and four isolates from green bristlegrass were identified as and another 103 isolates from crabgrass, green bristlegrass, goose grass, foxtail millet, wild millet, rice, and sedge belonged to . Results of pathogenicity tests by artificial inoculation demonstrated that six of 10 isolates from rice and three of 44 isolates from green bristlegrass showed cross-infectivity on green bristlegrass and rice, respectively. Taken together, our results demonstrated that isolates from green bristlegrass and crabgrass consist of both and and that isolates showed cross-infectivity between rice and green bristlegrass, suggesting that host shifts may occur for and .
和 是多种禾本科宿主上重要的主要疾病的病原体。虽然 是引起稻瘟病爆发的最重要病原体，但 主要是稗草的病原体。在这项研究中，从 7 种植物中收集了 103 个 和 20 个分离株，我们分析了它们的系统发育、致病性和与宿主偏好的关系，以研究它们在不同宿主之间的差异。基于多位点序列的系统发育分析，从稗草中分离出的 16 个分离株和从绿色画眉草中分离出的 4 个分离株被鉴定为 ，而从稗草、绿色画眉草、狗尾草、谷子、野生小米、水稻和莎草中分离出的另外 103 个分离株属于 。人工接种致病性试验的结果表明，来自水稻的 10 个分离株中的 6 个和来自绿色画眉草的 44 个分离株中的 3 个分别对绿色画眉草和水稻具有交叉感染性。总之，我们的结果表明，来自绿色画眉草和稗草的分离株既包含 又包含 ，并且 分离株在水稻和绿色画眉草之间表现出交叉感染性，这表明 和 可能发生宿主转移。
