大豆锈病是秋大豆的主要病害。冬豆、春豆上也有发生。1970年后,锈病日趋严重,尤其是1972年以来,在有的地方的秋大豆上大流行,导致产量下降,种植面积减少,轻病减产10%左右,重病年能减产50—60%。大豆锈病寄主,仅限于豆科植物。此病除危害大豆外,尚可侵染野大豆、豆薯、葛及豇豆等豆科植物。一、症状大豆锈菌主要侵染叶片,叶柄、茎也能受害。发病初期,叶片上出现黄色点状病斑,以后病斑稍扩大,呈黄褐色小斑,无晕圈,迎光透视更为明显。侵染量 Soybean rust is the main disease of autumn soybean. Winter beans, spring beans have also occurred. After 1970, the rust became more and more serious. Especially since 1972, the epidemic of autumn soybean in some places has led to the decline of output and the reduction of planting area. About 10% of the cases of light illness and 50-60% of the cases of serious illness have been cut off. Soybean rust host, limited to legumes. In addition to endangering the disease of soybeans, but also invade wild soybeans, bean, Ge and cowpea and other legumes. First, the symptoms of soybean rust infected mainly leaves, petiole, stem can also suffer. Early onset, the leaves appeared yellow spot-like lesions, slightly enlarged after the lesion was yellowish brown spots, no halo, Yinguang perspective more obvious. Infestation volume