柑桔流胶病的病因较复杂 ,主要由菌核菌、树脂菌、疫菌和灰霉菌 4种真菌引起。根据病斑在田间复发侵染和自愈现象 ,可将病斑症状分为 :无明显伤口病斑和有明显伤口病斑两大类 ,前者又可分为流胶腐烂型 (病部皮层腐烂 ,不易愈合 ,持续时间长 ,流胶量多 ,为田间发病的主要类型 ) The causes of citrus gum disease is more complicated, mainly caused by four kinds of fungi, sclerotium, resinous bacteria, epidemic bacteria and gray mold. According to the lesion in the field of recurrence of infection and self-healing symptoms, lesions can be divided into: no obvious wound lesions and obvious lesions of the two major categories, the former can be divided into the flow of plastic decay type (diseased cortex rot , Not easy to heal, long duration, the amount of plastic flow, the incidence of the main types of field)