尚义县地处坝上高原，近年来随着蔬菜种植面积的逐年增加和蔬菜流通的日趋活跃，＿病虫害问、题也日渐突出。1998年全县甘蓝黑腐病的发病面积就达600hnlz，发病率高达80％多；病叶率为14．3％一57．1％，据调查估算，约造成10％～20％的经济损失。其主要发病原因一是秧苗?.. Shangyi County is located in the dam plateau in recent years with the growing area of ​​vegetable cultivation and vegetable circulation has become increasingly active, _ pests and diseases, the problem has become increasingly prominent. In 1998 the county black cabbage black rot disease area reached 600hnlz, the incidence rate as high as 80%; diseased leaf rate of 14.3% 57.1%, according to survey estimates, resulting in about 10% to 20% of economic losses . The main cause of the first is the seedling? ..