溃疡病是杨树上发生最普遍、危害最严重的病害之一,常引起幼树死亡和大树枯梢,严重影响树木生长。尤以箭杆场、北京杨等杂交杨发病最高。发病初期,树干皮孔附近出现水泡,手压即有液体流出。水泡破裂后流出带臭液体,内有大量细菌。最后,病部干缩下陷成 Canker disease is one of the most common and hardest diseases on poplar trees. It often causes the death of young trees and dead trees, which seriously affect the growth of trees. Especially in Arrow Field, Beijing Yang and other hybrid Yang highest incidence. Early onset, blisters appear near the trunk lenticels, hand pressure that liquid outflow. After blisters rupture with outflow of liquid, there are a large number of bacteria. Finally, the disease shrinks into a dry stem