【作者】 黎妍妍； 冯吉； 王林； Tom Hsiang； 李锡宏； 黄俊斌；

【Author】 Yanyan Li;Ji Feng;Lin Wang;Tom Hsiang;Xihong Li;Junbin Huang;Tobacco Research Institute of Hubei Province;The Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University;China Tobacco Hubei Industrial Co., Ltd.;Environmental Sciences, University of Guelph;

【机构】 湖北省烟草科学研究院； 华中农业大学植物科技学院湖北省作物病害监测和安全控制重点实验室； 湖北中烟工业有限责任公司； 加拿大圭尔夫大学环境科学学院；

【摘要】 由青枯劳尔氏菌引起的青枯病是我国烟草最严重的土传病害。2012～2014年间,从我国四个主产烟区分离获得89个烟草青枯菌菌株,并对其进行了遗传多样性和致病力分析。根据内切葡聚糖酶(egl)基因序列,我国烟草青枯菌为演化型I(亚洲分支),并可划分为7个序列变种(13、14、15、17、34、44和54)。其中,序列变种15、17、34和44已有报道;序列变种13和14在本研究中首次报道可以侵染烟草。同时,也发现了一个新的序列变种54。不同区域的烟草青枯菌表现出不同的遗传多样性水平:地理分布越往北,烟草青枯菌的遗传多样性越低。通过人工接种三个不同抗性的烟草品种测定了27个代表性菌株的致病力。基于病害流行下曲线面积(AUDPC),聚类分析可将27个菌株划分为高、中、低三种致病型。序列变种和致病型间不存在明显的相关性。更多还原

【Abstract】 Bacterial wilt caused by Ralstonia solanacearum is the most serious soil-borne disease of tobacco(Nicotiana tabacum) in China. In this study, 89 strains were collected in 2012 to 2014 from across the four major tobacco-growing areas in China. The strains were identified as phylotype I by multiplex PCR and further divided into seven sequevars based on polymorphisms in the egl gene. Among the seven sequevars, four(15, 17, 34 and 44) have been previously described as pathogens of tobacco, and two(13 and 14), which are reported here on tobacco, were previously found only on other plants. As well, a new sequevar named 54 was identified. Strains from tobacco from different regions showed different levels of genetic diversity based on partial egl gene sequences. The farther north the distribution, the lower the gene diversity found.Pathogenicity of 27 representative strains was assessed by inoculation onto three tobacco cultivars of varying susceptibility. Through cluster analysis of AUDPC values, the 27 strains were classified into different pathotypes based on virulence, but no obvious associations were found between sequevar and pathotype. These results will assist in determining geographical distribution of strains, and provide the foundation for breeding and integrated management programs in China.更多还原