杨叶枯病病原菌生物学特性初步研究

Bionomics of Alternaria alternate in(Populus) spp.

杨叶枯病Alternaria alternate（Fr．）Keissler是一种发生普遍且危害严重的杨树叶部病害。该菌的生长发育温度在5～35℃，菌丝和分生孢子的最适生长温度在20～30℃之间，孢子的致死温度为52℃，菌丝的致死温度为55℃。在pH3～10之间的培养基上均可生长，以pH值6～8为最佳。有无光照处理对菌丝生长差异明显，以黑暗与日光灯交替处理病原菌生长较快。在PDA培养基黑暗条件下培养该菌生长良好，其次是胡萝卜汁培养基，但在琼脂加水培养基上产孢效果最好。

Alternaria alternate Populus （Ft.） Keissler was a important pathogen of popular leaf disease in Populus spp., The results of the biological determination showed that the temperature for the growth and development of the pathogen was 5-35℃, the optimum temperature for the growth of mycelium and spores was between 20 and 30 ℃, and the lethal temperature of spores was 52 ℃, for mycelium,it was 55 ℃. The mycelium could grow on the medium with pH 3-10,the optimum pH was between 4.5 and 9.5. The difference was obvious for mycelial growth between the treatments of darkness and fluorescent light. The treatment of alternation of darkness and fluorescent light favored the mycelial growth. The best medium for the pathogen development was PDA, Next carrot juice culture medium. Medium of Agar-agar plus water was the best for the spores reproduction.