烟草赤星病是烟叶成熟期的一种重要真菌病害。在我国,菌核净(dimethachlon)是防治该病的主要药剂之一。但是,生产上菌核净的长期大量使用及使用技术的不合理,导致抗药性菌株的产生[1]。贵州是我国重要的烟叶产地,菌核净已使用多年,一旦烟草赤星病菌Alternaria alternata(Fries)Keissler普遍对菌核净产生抗性,将对烟叶产业造成严重影响。目前关于烟草赤星病菌对菌核净的抗性水平尚未明确,为此,本研究对贵州不同地区的该病菌进行 Tobacco brown spot disease is an important fungal disease in the mature tobacco leaves. In our country, dimethachlon is one of the main agents for the prevention and treatment of the disease. However, the long-term mass production of sclerotium and the use of unreasonable technology, leading to the emergence of resistant strains [1]. Guizhou is an important tobacco producing area in China. Sclerotium has been used for many years. Once the broad-spectrum resistance of Alternaria alternata (Fries) Keissler to the sclerotia of Tobacco has been severely affected, the tobacco industry will be severely affected. At present, the level of resistance to the sclerotinia of Alternaria solani has not been clarified yet. To this end, the study of this pathogen in different areas of Guizhou