一种引起虎皮兰叶斑病的刺孢壳属真菌的生物学特性（英文）

Biological Characteristics of Chaetomella sp.(Sphaeropsidaceae),A Novel Causal Agent of Sansevieria Leaf Spot Disease

【目的】研究一种引起虎皮兰叶斑病的刺孢壳属真菌 HPL06的生物学特性，为了解其潜在危害及制定科学的防治方案提供依据。【方法】将 HPL06于多种光照（自然光、12 h光照/12 h黑暗、24 h光照、24 h黑暗）、温度（5，10，15，20，25，30，35，40℃）、pH（4，5，6，7，8，9，10，11）、氮源（天冬酰胺、氯化铵、硝酸钾、硫酸铵、谷氨酸）和碳源（蔗糖、果糖、乳糖、麦芽糖、葡萄糖）条件下进行培养，采用十字交叉法测量菌落直径，分析不同环境因子对病原菌生长的影响；用 HPL06菌饼和孢子悬浮液进行离体叶片接种，检测病原菌对23科62种植物的致病性。【结果】HPL06在4种光照条件下均能生长，光照有利于菌丝生长，24 h 光照对菌丝生长最有利；在极端温度（5，10，40℃）条件下病原菌不能生长，其他温度下均能生长，菌丝生长的最适温度为25～30℃；病原菌能在 pH 为4～11的条件下生长，最适 pH 为4；5种供试碳源中，病原菌均可正常生长，葡萄糖对菌丝生长最有利；5种供试氮源中，天冬酰胺对病原菌的生长最有利，其菌丝在 PDA 培养基中生长最快。HPL06对20科46种植物具有致病性，其中菌饼接种发病的植物为20科46种，孢子悬浮液接种发病的植物为12科30种。【结论】刺孢壳属真菌 HPL06对环境因子适应性范围较广，仅在低于10℃或高于40℃时不能生长；而且寄主范围广，在被检测的23科62种植物中，对74.19%的植物均具有致病性，在自然界中可能还存在更多的寄主植物。

Objective]This study aims at evaluating the effects of environmental factors and susceptibility of various plant species to pathogens causing Sansevieria leaf spot disease for developing the control methods and strategies. [Method]We investigated the biological characteristics of the HPL06 isolate of Chaetomella sp. that causes leaf spot on Sansevieria trifasciata Prain cv. ‘Hanii ’ in China. The fungus was incubated in different conditions （ i. e. light environments,temperature,pH,nitrogen and carbon sources）. Colony diameters were measured using the CM method. The optimal environmental factors for the fungal growth were analyzed. A host spectrum of the isolate was also investigated on 62 plant species covering 23 families using a detached leaf inoculation technique. [Result]Results showed that the optimal illumination and temperature for hyphal growth were 24 h of fluorescent light and 25 -30 ℃,respectively. The pathogen could grow at pH 4 -11 ,but the optimal pH was 4 . The optimal carbon and nitrogen sources were glucose and asparagine,respectively,and the hyphae exhibited optimal growth on PDA plates. A total of 46 species belonging to 20 families were susceptible to Chaetomella sp. HPL06 .[Conclusion]The isolate could adapt to various environments. The fungus could not grow below 10 ℃,or above 40 ℃. Chaetomella sp. HPL06 can cause diseases in many plants. A number of plants were found to be susceptible to Chaetomella sp. with 74 . 19% of the total number of the tested 62 plant species. A large number of plants susceptible to Chaetomella sp. HPL06 may exist in nature. In order to avoid even greater economic losses caused by the fungus,further field studies on the occurrence of the new Sansevieria leaf spot disease are needed to establish a science-based disease management strategy.