翠菊立枯病在华北、东北均有发生。其侵染部位分为首腐、根腐、猝倒、立枯等。一、发生规律病菌以菌丝体和菌核在土中越冬。土壤是主要侵染源,病株残余、肥料也有传病可能,还可通过流水、农具、人畜等传播。多年连作地发病严重。尖镰孢霉在土壤温度23——32℃时都能侵染,土壤酸度8.9时最 Aster blight in North China, Northeast have occurred. The infected parts are divided into the first rot, root rot, cataplexy, standing dead and so on. First, the occurrence of regular bacteria to mycelium and sclerotinia in the soil overwintering. Soil is the main source of infection, diseased strains are residual, fertilizers are also possible disease, but also through the water, farm tools, livestock and other transmission. For many years even serious onset. Fusarium oxysporum in soil temperature 23--32 ℃ can be infected, the soil acidity 8.9 most