向日葵黄萎病菌生物学特性及致病性研究

Research on Biological Characteristics and Pathogenicity of Sunflower Verticillium wilt Pathogen

【目的】明确新疆向日葵黄萎病病原菌种类,分析病害规律,研究防病关键技术。【方法】采用形态分类方法对病原菌进行种的鉴定,采用一般生物学方法对病原菌重要生物学特性及致病性进行研究。【结果】病原菌种的鉴定结果表明,新疆向日葵黄萎病主要致病菌为大丽轮枝菌(Verticillum dahliae)和硫色轮枝菌(Verticillum sulphurellum);病原菌生物学特性研究表明:两种病原菌的生长周期及温度适应性基本一致,生长周期约为10 d,病菌生长温度范围为10～30℃,最适生长温度为25℃,致死温度为52℃;大丽轮枝菌较适宜的酸碱范围为pH 5.1～11.1;硫色轮枝菌在pH 4.1～11.1均可生长;在多种常用培养基中,燕麦培养基是大丽轮枝菌的最适培养基;而玉米片培养基是硫色轮枝菌的最适培养基。致病性研究表明:自然条件下,病菌自苗期开始整个生育期均可侵染;人工接种条件下,高湿及有伤接种有利于侵染和发病。【结论】新疆向日葵黄萎病的主要病原菌为大丽轮枝菌和硫色轮枝菌,两种病原菌对向日葵均有较强的致病性。

[ Objective ] In order to clarity species of sunflower VerticiIlium wilt pathogen, analyze the occurring regularity of the disease and study the key control technology. [ Method] In the research, species of the pathogens are identified by morphology and biological methods used; and the important biological characteristics and pathogenicty of the pathogens are researched by general biologic method applied. [ Result] The identified results of pathogen show that main pathogens causing those sunflower Verticillium wilt are Verticillum dahliae and Verticillum sulphurellum in Xinjiang; Research on biological characteristics shows that two of the pathogens growth cycle and temperature adaptability are almost the same, their growth cycle is about 10 d, and their growth temperature range is from 10℃ to 30℃, the optimum growth temperature is 25℃, and their lethal temperature are 52℃ ; Verticillum dahliae＇s more suitable pH range is pH 5.1 - 11.1 ; Verticillum sulphurellum all can grow in range of pH 4.1 - 11.1 ; In several common medium, OMA is the best medium for Verticillum dahliae, And CMA is the optimum medium for Verticillurn sulphurellum; research on infection characteristics shows that, in natural conditions the pathogens can infect the plant in the entire growth period since the start of the seedling stage; in the artificial inoculation, high moisture and wound - infection are beneficial to the pathogens that infect the plant and cause disease. [ Conclusion] Main pathogens of sunflower verticillium wilt are Verticillum dahliae and Verticillum sulphurellum in Xinjiang, Both of the pathogens have strong pathogenicity to sunflower.