柚类黑斑病是一种早期 (幼果期 )侵染、后期 (近成熟期 )表现症状的病害。潜育期较长 ,主要为害果实 ,也可为害叶片和枝梢。根据被害果实的症状又可分为黑星型和黑斑型。黑星型 :受害果初生红褐色小斑 ,后扩大至圆形 ,周围隆起 ,红褐色至黑褐色 ,中央凹陷 ,灰褐色 ,其上散生许 Pomelo black spot disease is an early (young fruit) infection, late (near maturity) symptoms of the disease. Longer incubation period, the main fruit damage can also damage the leaves and shoots. According to the symptoms of the victim fruit can be divided into black star type and black type. Black star type: Victims Primary reddish brown small spots, enlarged to round, around the uplift, reddish brown to dark brown, central depression, taupe, scattered on the Health Xu