乌头根腐病病原菌的分离与鉴定

Isolation and identification of pathogens causing root rot on Aconitum carmichaelii Debx.

摘要:

【背景】四川江油地区栽培乌头极易发生根腐病，植株染病后枯萎死亡，最终影响药材产量。因发病因素和致病菌多样，乌头根腐病的防治向来困难。【目的】鉴定四川江油地区栽培乌头根腐病病原菌，为病害诊断和防治提供理论基础。【方法】采用组织分离法进行病原菌分离；按照Koch’s法则对分离的病菌进行致病性验证；通过形态学观察和真菌rDNA-ITS序列分析，鉴定病原菌种类。【结果】从具有根腐病症状的乌头根部分离得到47株真菌，其中菌株GF3-3、GF3-6和GF6-1是乌头根腐病的致病菌；通过形态特征结合rDNA-ITS序列分析将菌株GF3-3、GF3-6和GF6-1分别鉴定为Fusarium solani、F. oxysporum和F. proliferatum。【结论】茄腐镰刀菌(F. solani)、尖孢镰刀菌(F. oxysporum)和层出镰刀菌(F. proliferatum)是乌头根腐病的主要病原菌，其中层出镰刀菌引起乌头患根腐病为首次报道。

Abstract:

[Background] Root rot is highly susceptible to the cultivated Aconitum carmichaelii Debx. in Jiangyou area of Sichuan, China. The plants wither and die after being infected by root rot, which ultimately affects the yield of medicinal materials. The prevention and treatment of the root rot are difficult due to complex pathogenic factors and the diversity of pathogenic fungi. [Objective] To identify the pathogens of root rot on A. carmichaelii Debx. cultivated in Jiangyou area, and to provide theoretical basis for diagnosis and prevention of the disease. [Methods] Pathogen isolation was carried out by means of diseased tissue isolation method. Koch’s rule was used to prove the pathogenicity of fungal strain isolated from A. carmichaelii. The pathogens were identified based on their morphological characteristics and rDNA-ITS sequence. [Results] Forty-seven fungi isolates were isolated from the root rot of A. carmichaelii. Strains GF3-3, GF3-6 and GF6-1 were the causal pathogen fungi of the root rot of A. carmichaelii. The pathogen strains GF3-3, GF3-6 and GF6-1 were identified as Fusarium solani, F. oxysporum and F. proliferatum via morphological characteristics and rDNA-ITS sequence. [Conclusion] Fusarium solani, F. oxysporum and F. proliferatum were the principal pathogenic fungi causing root rot disease of A. carmichaelii. This is the first report of root rot of A. carmichaelii caused by F. proliferatum.