一、杨树溃疡病概况世界已发表的引起杨树溃疡病的病原菌共有20余种(见表1),我国有8-9种(见表2)。其中严重发生于欧洲、亚洲、北美各国的世界性溃疡病有杨树腐烂病(Cytospora chrysosperma、Valsa sordida)、杨树疡壳孢溃疡病(Dothichizapopulea)等,据目前了解,有些杨树溃疡病还 First, the poplar ulcer disease profile There have been published in the world cause poplar canker disease pathogen a total of more than 20 species (see Table 1), China has 8-9 species (see Table 2). One of the most serious ulcer diseases in Europe, Asia and North America is Cytospora chrysosperma (Valsa sordida) and Dothichizapopulea (Populus tomentosa). According to the current understanding, some poplar canker diseases