卷丹鳞茎腐烂病菌的生物学特性及防病药剂筛选

Biological characteristics of Fusarium proliferatum causing medicinal lily bulb rot disease and its fungicides screening

层出镰刀菌(Fusarium proliferatum)是新发现的可引起药用植物卷丹鳞茎腐烂的病原菌,为了解该菌的环境适应性,以便具有针对性地制订防治策略,对其生物学特性开展了室内单因素研究,分别调查在不同温度、光照、pH、培养基、碳氮源条件下该菌的菌丝生长与产孢情况;采用菌丝生长速率法测定该菌对5种杀菌单剂与3种复配剂的敏感性。结果表明,供试菌菌丝生长与产孢的最适温度为25℃,最适pH为7,黑暗条件利于产孢;在CMA培养基上菌丝生长最快,在PDA培养基上产孢最多;菌丝生长的最适碳源为蔗糖,氮源为硝酸钠;产孢的最适碳源为果糖,氮源为牛肉浸膏。供试单剂以戊唑醇的抑菌效果最好,EC_(50)为0.200 8 mg/L,复配剂以异菌·氟啶胺的抑菌效果最好,EC_(50)为0.401 8 mg/L。戊唑醇对卷丹鳞茎腐烂病的防效相对较高,离体浸球防效、盆栽拌土防效分别为60.78%、40.35%。

Fusarium proliferatum is a recently identified pathogen causing the medicinal plant Lilium lancifolium bulb rot disease in Beijing. To understand the environmental adaptability of this pathogen and inform the development of control strategies, a series of single-factor experiments were conducted to determine its biological characteristics. The sensitivity of this pathogen to five individual fungicides and three fungicide mixtures was evaluated using the mycelial growth rate method.The results showed that the optimal conditions for mycelial growth and spore production of the F. proliferatum isolate were 25℃ and pH 7. This fungus exhibited a preference for dark conditions, which enhanced its spore production. The mycelium grew fastest on the CMA medium, while the sporulation was prolific on the PDA medium. The most suitable carbon and nitrogen sources for mycelial growth were identified as sucrose and sodium nitrate, while those for sporulation were fructose and beef extract, respectively. The laboratory screening of fungicides against F. proliferatum isolate indicated that tebuconazole showed the best inhibitory effect among the five individual fungicides, with an EC_(50)of 0.200 8 mg/L, and the mixture comprising iprodione and fluazinam showed the most pronounced inhibitory effect among the three mixtures, with an EC_(50)of 0.401 8 mg/L. The control efficacy of tebuconazole on medicinal lily bulb rot disease was 60.78% in the soaking experiment and 40.35% in the pot experiment. These results provide a reference for the prevention and control of medicinal lily bulb rot disease.