芹菜斑枯病又叫晚疫病、叶斑病，俗称“火龙”，是大棚芹菜的重要病害，对芹菜的质量和产量有很大影响。一、发病症状植株地上部分都能感病受害，但以叶片为主。发病最初在叶片上产生浅黄色水渍状小病斑，呈圆形或近圆形，多群集散生，常相互融合成不规则形斑块，直径2～5毫米 Celery blight known as late blight, leaf spot disease, commonly known as “fire dragon” is an important disease greenhouse celery, celery quality and yield have a significant impact. First, the symptoms of the disease can affect the upper part of the victims, but mainly leaves. The incidence of the first light yellow water stain on the leaves of a small lesion, was round or nearly circular, multiple clusters of loose, often fused into irregular shaped plaque, diameter 2 ~ 5mm