榆树是我国北方的主要造林树种之一。近年来随着榆树造林面积的扩大,榆树溃疡病(Ascochyta ulmi(West)Kleber)在辽宁省各地苗圃及农田防护林中相继发生,主要危害1—7年生的白榆。该病是危害榆树枝干的一种危险性新病害,目前其发生面积已占全省榆树面积的29%,严重地块发病率达90%,感病指数达80%,已给林业生产造成了严重的损失。 Elm is one of the main afforestation species in northern China. In recent years, with the expansion of elm afforestation area, Ascochyta ulmi (West) Kleber occurred successively in nurseries and farmland shelterbelt around Liaoning Province, which mainly endangered elm trees aged 1-7 years. The disease is endangered elm tree branches a dangerous new disease, the occurrence of the area now accounts for 29% of elm area in the province, the incidence of serious block 90%, the index of 80%, has given the forestry production A serious loss.