江西奉新县猕猴桃叶斑病病原菌鉴定

摘要

为明确江西奉新县猕猴桃一种新的真菌性叶斑病病原菌种类,对采集的病叶样品进行了真菌分离,对分离菌株进行了形态学和分子生物学鉴定,并作了致病性测定.共分离得到32个真菌菌株,其在人工接种实验中均具有致病性.各菌株的培养特征、分生孢子形态大小相同,均符合文献中对多主棒孢的描述.随机选取3个菌株,测定了其rDNA-ITS序列,3个菌株的序列相同,且与GenBank中的多主棒孢的对应序列具有100%的同源性.据此认为,奉新猕猴桃叶斑病的病原菌种类为半知菌类棒孢属中的多主棒孢(Corynespora cassiicola).%In order to ascertain the fungal species responsible for the new kiwifruit leaf disease in Fengxin County of Jiangxi Province,a fungus was isolated from the diseased leaf samples by using the tissue isolation method.The obtained fungus was identified based on morphology and molecular biology,and its pathogenicity was tested.In total,32 fungal isolates with pathogenicity in artificially inoculation test were obtained.The cultur-al characters and conidial morphology and size of each isolate were identical, and consistent with those of Corynespora cassiicola in literature. Three isolates were randomly selected for analyzing their rDNA-ITS se-quences.The three rDNA-ITS sequences obtained were the same and identical to that of C. cassiicola. Thus,it may be concluded that the pathogen of kiwifruit leaf spot disease in Fengxin County of Jiangxi Province is Corynespora cassiicola,a species of genus Corynespora in fungi imperfect.