梨树疫腐病又叫疫病,黑胫病。此病发病快,死亡率高,是一种毁灭性病害。1发病症状该病主要发生在鸭梨幼树主干基部,砧穗接口以上,病部树皮呈黑褐色,形状不规则,从表皮发病到木质部。随着发病时间的延长,病部组织坏死,干缩下陷,病健交界处龟裂,当病斑绕树干一周时,形成层被破坏,? Pear blight also known as disease, black shank disease. The disease is fast onset and has high mortality rate, which is a devastating disease. 1 disease symptoms The disease occurs mainly in the base of pear saplings, scion spike interfaces above the diseased bark was dark brown, irregular shape, the incidence from the epidermis to the xylem. With the extension of the onset of disease, the diseased tissue necrosis, shrinkage shrinkage, disease junction health crack, when the lesion around the trunk a week, the formation of layers is destroyed,?