一、疫霉根腐病该病由寄生疫霉和辣椒的疫霉侵染所致,地温低湿度高或高温高湿条件下易发病。主要危害番茄、辣椒、黄瓜、西葫、茄子等蔬菜。发病植株茎基部或根部出现褐斑,逐渐扩大并凹陷,严重时病斑可绕茎基部一周,后根茎基部腐烂,不发新根,地上茎叶逐渐萎蔫枯死,纵剖病株根茎部,可见导管变成深褐色。 First, Phytophthora root rot The disease caused by parasitic Phytophthora capsici and Phytophthora capsici caused by low temperature and humidity or high temperature and humidity conditions prone disease. Mainly harmful to tomatoes, peppers, cucumbers, zucchini, eggplant and other vegetables. Occurred at the base of the plant stem or root brown spots, and gradually expand and depression, severe lesions around the base of the week after the disease, after the base rotten roots, no new roots, the ground stems and leaves wilted wither, The catheter becomes dark brown.