沙田柚炭疽病以春季发病率最高 ,为害最严重 ,主要为害新抽生的嫩梢、嫩叶和幼果。春梢受害时 ,常在嫩梢顶端 3～ 10ｃｍ处突然发病 ,如开水烫伤状 ,呈暗绿色水渍状 ,几天后凋萎变黑 ,嫩梢部出现朱红色小粒点 ,然后自上而下枯死。嫩叶受害 ,先出现青色或暗褐色如开水烫伤的小斑 The anthracnose of Shatian pomelo has the highest incidence in spring and the worst damage, mainly affecting young shoots, young leaves and young fruits. Spring shoot victims, often in the top of the tender tip 3 ~ 10cm Department of sudden onset, such as boiled water scalded, dark green water-like, wilting a few days after the black, tender tip appears vermilion small particles, and then from the top Death under. Injured young leaves, first appear cyan or dark brown, such as boiled water spots