广东西番莲茎基腐病病原的分离及鉴定

Isolation and identification of the pathogen causing stem rot disease of Passiflora Linn. in Guangdong

[目的]明确引起广东西番莲茎基腐病的病原菌,为有效防治该病害提供理论依据。[方法]采用组织分离法对广东番莲茎基腐病的病原进行分离,利用柯赫氏法则测定病原菌的致病性,光学显微镜观察病原菌分生孢子的形态学特征,测序分析病原菌的rDNA ITS序列。[结果]基于柯赫氏法则的致病性测定,证实从发病西番莲茎基部主干分离获得的病原菌对西番莲具有致病性。BLAST在线比对分析结果显示,病原菌rDNA ITS序列与多个腐皮镰孢菌菌株的相似性在99%以上。结合病原菌形态学特征、致病性测定及rDNA ITS序列分析结果,可确定引起广东西番莲茎基腐病的病原菌为腐皮镰孢菌[Fusarium solani(Mart)Sacc)]。[结论]近年来引起广东西番莲茎基腐病的病原菌为腐皮镰孢菌。防治西番莲茎基腐病需注重早期预防,提早防治;合理规划种植,加强栽培;做好冬季清园,合理疏剪。

[Objective]The aim of the study was to clarify the pathogen causing stem rot of Passiflora Linn.,and provide a theoretical basis for effective prevention and treatment of the disease.[Method]The pathogen was obtained by tissue separation method,and the pathogenicity of the pathogen was determined by Koch’s rule. The morphological characteristics of the conidia of the pathogen were observed by optical microscope,and the rDNA-ITS sequence of the pathogen was analyzed by online BLAST.[Result]Based on the pathogenicity measurement of Koch’s rule,it was confirmed that the isolated bacteria from the stem stalk was pathogenic to Passiflora Linn.. The BLAST online alignment showed that the similarity between the pathogen ITS sequence and those of multiple Fusarium solani strains was over 99%. Combined with the pathological characteristics of pathogen,the pathogenicity determination and sequence analysis of ITS,the pathogen causing stem rot of Passiflora Linn. was identified as Fusarium solani(Mart)Sacc.[Conclusion]F. solani is the pathogen that can infect the base stem of Passiflora Linn. Controlling the stem rot of Passiflora Linn. requires early prevention,planning planting,strengthening cultivation,clearing garden and rationally cutting.