一、大豆霜霉病的防治霜霉病在大豆整个生育期均有发生，主要危害叶片和籽粒，成株期叶片上病斑散生，呈圆形或不规则形的黄绿色小斑点，叶背有灰霉，呈星芒状。病斑扩大后呈黄褐色，周围深褐色，与健康部分界明显，发病重时，病斑汇成大斑，叶片干枯早期大量脱落。病粒表... First, the prevention and control of soybean downy mildew Mildew in soybean throughout the reproductive period have occurred, the main hazards of leaves and grains, adult leaves on the diseased spots scattered round or irregular yellowish green spots, leaves Back with gray mold, star-shaped. Lesions enlarged yellowish brown, dark brown around, and the health sector clear boundary, severe onset, spot merged into large spots, leaves a large number of early dry off. Patient Table ...