湖南烟草靶斑病的病原鉴定及分子检测

Pathogen identification and molecular detection of tobacco target spot in Hunan Province

2019至2020年,在湖南省郴州、永州、湘西和常德烟区发生了一种严重的叶部病害,表现为叶部出现圆形或不规则黄褐色病斑,有不规则同心纹,病斑周围可见黄绿色晕圈,后期易破裂穿孔。经组织分离、形态学观察、分子鉴定以及柯赫氏法则验证,确定该病害为烟草靶斑病,病原为立枯丝核菌(Rhizoctonia solani Kola)。在此基础上,以烟草靶斑病菌rDNA–ITS序列为靶标,设计特异性引物Rs–1,建立了特异性针对靶斑病菌的PCR检测体系,从烟草病斑处检测烟草靶斑病菌。

From 2019 to 2020,a serious leaf disease was found in Hunan Province including Chenzhou,Yongzhou,Xiangxi and Changde.Symptoms displayed as round or irregular brown spots,with irregular concentric pattern and yellow-green halo and later the infected leaves were easy to rupture and perforate.The pathogen was confirmed to be Rhizoctonia solani Kola via tissue isolation,morphological observation,molecular identification and Koch’s Postulates.On this basis,a direct PCR method for detection of tobacco target spot was established using the specific primers Rs-1F and Rs-1R designed based on the rDNA-ITS sequence of the pathogen.Using this method,the pathogen fungus could be detected directly from the disease spots on tobacco leaves.