哈尔滨地区早开堇菜叶斑病的病原菌鉴定

Identification of Pathogen Causing Leaf Spot on Viola prionantha in Harbin Area

早开堇菜(Viola prionantha Bunge)又名早花地丁,是一种具有药用价值的多年生草本植物,也是一种美丽的早春观赏植物。2020年在黑龙江省哈尔滨市发现一种早开堇菜叶斑病,为了明确引起这种病害的病原菌,采用组织分离法,对病原菌进行形态学和分子生物学鉴定,再通过柯赫氏法则进行验证。结果表明,引起哈尔滨地区早开堇菜叶斑病的病原菌为楸子茎点霉(Didymella pomorum),它的分生孢子单胞无色,长椭圆形,大小为4.60~8.06μm×2.38~3.81μm,该病菌在PDA培养基上生长良好,菌丝浓密,呈绒毛状。本研究报道的关于楸子茎点霉引起的早开堇菜叶斑病为首次报道,今后要加强对早开堇菜叶斑病发生规律和防治药剂筛选的研究。

Viola prionantha Bunge is a kind of perennial herb of medicinal value,and is also a kind of beautiful spring ornamental plants.In 2020,a unknown leaf spot disease of V.prionantha was found in Harbin City,Heilongjiang Province.In this study,the pathogen was identified with the method of morphological and molecular identification,and then verified according to the Koch′s rule.The results showed that the pathogen causing this disease was Didymella pomorum,its conidia were colorless,single-celled,rounded to ellipsoidal,and the size of conidia was 2.38-3.81μm×4.60-8.06μm.The pathogen grew well on PDA medium,and its hyphae were thick.This is the first report of D.pomorum causing leaf spot disease on V.prionantha in China,it is necessary to strengthen the research on the occurrence of this disease and the selection of control agents in the future.