一、发病症状 发病初期在叶片或枝干表面产生圆形或不规则形的黑色煤斑,逐渐扩大后布满全叶,并蔓及小枝及茎干。随着病害不断发展,便造成整丛乃至成片茶树一片乌黑。 二、发病规律 病菌在茶树病部越冬,翌春在适宜的温湿条件下形成孢子,随风雨传播,落在蚜虫、粉虱或蚧壳虫的分泌物上,摄取营养,病菌萌发长出菌 First, the incidence of disease onset in the leaves or branches of the surface of round or irregular shaped black coal spots, gradually expanded and covered with whole leaves, and sprig and stems. With the continuous development of disease, it will cause the entire cluster and even into a piece of tea tree black. Second, the incidence of pathogens Pathogens in the tea tree overwinter, the next spring in the appropriate conditions of temperature and humidity to form spores, spread with the wind and rain, fell on the aphids, whiteflies or scale insects secretion, intake of nutrients, germs grow bacteria