西兰花贮藏期腐烂病病原菌鉴定及其生物学特性研究

Identification and biological characteristics of the pathogenic fungi causing rot disease of broccoli during storage

中文关键词:  西兰花腐烂病  病原菌鉴定  变红镰刀菌  藤仓镰孢菌  生物学特性

英文关键词:broccoli rot disease  pathogens identification  Fusarium incarnatum  Fusarium fujikuroi  biological characteristics

中文摘要:

      目的 确定引起兰州地区西兰花贮藏期间腐烂病的主要病原菌, 研究其生物学特性。方法 通过形态学结合分子生物学方法对西兰花贮藏期间腐烂病病原菌进行分离纯化及鉴定, 确定造成西兰花腐烂病的主要病原真菌, 进一步采用菌丝生长速率法, 测定光照、pH、温度、培养基、不同碳源和氮源对病原菌生长的影响。结果 经分离鉴定发现西兰花贮藏期间腐烂病的主要病原真菌为变红镰刀菌(Fusarium incarnatum)和藤仓镰孢菌(Fusarium fujikuroi)。变红镰刀菌和藤仓镰孢菌最适生长温度、pH和培养基均为25 ℃、8和查氏培养基(Czapek’s medium, CDA)。但其对光照和碳氮源的利用存在差异, 变红镰刀菌在全光照条件下, 有利于菌丝生长, 最佳碳源为葡萄糖, 最佳氮源为蛋白胨; 而藤仓镰孢菌在光暗交替条件下有利于菌丝生长, 最佳碳源为淀粉, 最佳氮源为硝酸钠。结论 确定了引起西兰花贮藏期间腐烂病的主要病原菌为变红镰刀菌、藤仓镰孢菌, 并明确了其最适温度、光照条件、pH、培养基、碳源和氮源等生物学特性, 结果表明两株致腐镰刀菌具有碳氮源营养来源广泛, 适宜偏碱环境生长, 为西兰花贮藏病害的进一步有效防控提供理了论依据。

英文摘要:

      Objective To confirm the main pathogenic fungi causing rot disease of broccoli during storage in Lanzhou area, and study their biological characteristics. Methods The main pathogen causing rot disease of broccoli during storage was determined through isolating, purifying and identifying by morphological and molecular biological methods, and the effects of light, pH, temperature, medium, different carbon sources and nitrogen sources on the growth of pathogen were investigated by mycelium growth rate method. Results Fusarium incarnatum and Fusarium fujikuroi were found to be the main pathogenic fungi of rot disease in broccoli during storage. The optimum growth temperature, pH and medium for Fusarium incarnatum and Fusarium fujikuroi were 25 ℃, 8 and Czapek’s medium (CDA), respectively. However, differences in light type and carbon and nitrogen sources utilization were found. For Fusarium incarnatum, full light conditions, glucose and peptone was benefical for its mycelial growth, but Fusarium fujikuroi was conducive to mycelial growth under alternating light and dark conditions. The best carbon source was starch, and the best nitrogen source was sodium nitrate. Conclusion The main pathogens causing rot disease of broccoli during storage are identified as Fusarium incarnatum and Fusarium fujikuroi, and their biological characteristics such as optimum temperature, light conditions, pH, medium, carbon source and nitrogen source are determined. The study shows that the 2 strains of Fusarium spp. have a wide range of carbon and nitrogen sources and are suitable for growth in alkaline environment, which provides a theoretical basis for further effectively controlling broccoli storage diseases.