南瓜叶枯病病原菌生物学特性研究

本文对南瓜叶枯病病原菌瓜链格孢（Alternaria cucumerina）进行了生物学特性研究，结果表明：温度、pH、光照对其生长和产孢都有一定的影响。该病原菌菌丝生长、产孢和萌发的适宜温度为28 ℃，pH为7时菌丝生长最快，pH为8时最易产孢。25 ℃下连续黑暗培养产孢最多。碳、氮源对菌丝生长和产孢量有一定的影响，碳源中甘露醇组菌丝生长最快，山梨醇处理产孢量最多。氮源中牛肉浸膏最适宜菌丝生长和产孢，硫酸铵最差。该菌致死温度为50 ℃。

Studies on biological characteristics of the pathogen of the pumpkin leaf blight

The biological characteristics of the pathogen of the pumpkin leaf blight were studied. The results showed that temperature, pH and light affected the mycelial growth and sporulation of the fungus. The optimum growth temperature was 28 ℃; the suitable pH was 8; the best temperature for sporulation was 25 ℃ under dark condition. Both carbon and nitrogen sources had an effect on mycelial growth and sporulation. The growth of mycelia was the fastest with mannitol, and the number of sporulation was the largest with sorbitol. So did the nitrogen sources. Beef extract was the most suitable for the growth of mycelia and sporulation, while ammonium sulfate was the poorest. The lethal temperature to Alternaria cucumerina was 50 ℃.