一是掌握叶枯病、叶斑病和锈病的发病规律。病菌在病体上越冬,次年传入植株,并生大量分生孢子随气流传播,造成重复侵袭。一般在5月开始发病,6～7月为发病盛期,8月下旬至9月初当冬苗长到30厘米左右时病情减缓。当气温平均在24～26度,相对湿度85%左右易发病。二是在生长期间雨水多, First, control the incidence of leaf blight, leaf spot disease and rust. Pathogen overwintering in the body, the following year into the plant, and a large number of conidia with airborne spread, resulting in repeated attacks. Generally onset in May, 6 to July the peak incidence, late August to early September when the winter seedlings grow to about 30 cm when the disease slowed. When the average temperature of 24 to 26 degrees, 85% relative humidity prone to disease. Second, during the growing rain and more,