黑龙江省玉米弯孢菌叶斑病菌生物学特性研究

Study on the Biological Characteristics of Maize Curvularia Leaf Spot in Heilongjiang Province

为深入系统地研究玉米弯孢菌叶斑病菌病害的发病规律,对黑龙江省该病主要致病菌新月弯孢菌[Curvularia lunata(Wakker)Boed.]生物学特性进行了研究。结果表明:最适生长和孢子萌发温度为25～35℃,弯孢菌产孢适宜温度是25～30℃,其中30℃时菌落直径最大、孢子萌发率最高,产孢量为高峰(为产孢高峰)。在25℃条件下,相对湿度96%以上孢子开始萌发,随相对湿度的增加,萌发率也明显增加,分生孢子在水滴中萌发率最高。病原菌对酸碱度的适应范围较广,以pH6～8菌丝生长最适宜、产孢量最大;孢子萌发的适宜pH范围是5～8,最适pH为7。光照对菌丝体无显著影响,光暗交替有利于孢子的形成,光线对孢子萌发有抑制作用。

Some biological characters of Curvularia lunata in Heilongjiang province were studied.The results showed that the optimum temperature for pathogen hyphae growth and conidia germination was 25~35℃.The suitable temperature of spore production was 25~30℃.When the temperature was 30℃,colony diameter was largest,spore germination rate was highest,and sporulation was at the peak（for sporulation peak）.Spores began to germinate at 25℃ and relative humidity above 96%,with the relative humidity increasing,the germination rate increased significantly.The conidia germination rate was highest in water droplets.The pathogens could adapt wider scope of pH,the optimum pH for mycelial growth and sporulation maximum was 6~8,the suitable pH range for spore germination was 5~8,the best suitable pH was 7.The effect of light was not obvious to pathogen growth,alternating light and dark was good for the formation of spores and the spore germination could be inhibited for the light.