四川省玉米弯孢叶斑病菌的种类及生物学特性研究

Studies on the Classification and Biological Character of the Pathogen of Maize Curvularia Leaf Spot in Sichuan

为了明确引致四川省玉米弯孢菌叶斑病(Maize Curvularialeaf spot)的病原菌种类和优势种,以便为病害的防治和抗病育种提供依据,对所获得的78个弯孢菌(Curvularia)菌株采用形态学分类法进行种类鉴定,结果鉴定出6个种或变种,其中属于新月弯孢菌(Curvularia lunata)种类的菌株占种群的61.5%,新月弯孢菌是四川省玉米弯孢菌叶斑病的主要致病菌种类.对属于其中3个种的4个弯孢菌菌株进行生物学特性研究,结果表明,各供试菌株在不同条件下的生长速度都存在一定的差异.

Maize Curvularia leaf spot was listed as a quarantine disease in Sichuan. More than one hundred samples from different areas were collected and seventy-eight isolates were obtained for this study. According to the Ellis＇standard, the 78 isolates of Curvularia from different areas in Sichuan were classified into 6 species. Curvularia lunata（Warkker）Boedijn, Curvularia lunata var. aeria M. B. Ellis, Curvularfa senegalensis （Speg.） Subram, Curvularia pallescens Boedijn, Curvularia clavata Jain and Curvularia ovoidea （Hiroe ＆ watan） Muntanola and Curvularia lunata （Warkker）Boedijn was the dominant species causing Curvularia leaf spot of maize. The effect of temperature, pH, carbon and nitrogen on the growth of 4 strains of 3 Curvularia species were examined on certain plate. The range of temperature for growth of the four isolates was 10 ℃-35 ℃, and the optimum temperature for growth was 30 ℃-35℃. The range of pH for growth was 4-12 and the optimum pH value for growth was 6-8. The most suitable carbon source was Polysaccharide, such as inulin. The most suitable nitrogen source was organic nitrogen, such as glycine, but nitrogen source of NH4Cl was not suitable for growth of Curvularia isolates.