被害与诊断叶被害。起初,出现不规则的褐色的小斑点.但逐涨便扩大成为圆形、椭圆形,不正形等的褐色乃至黑褐色的病斑。病斑的形状,由于品种不同而有差异。另外,受叶脉限制,有时成为扇形,有时也呈现微小斑点汇合在一起。当大量病斑出现时,叶翘曲,而且病斑的周围发黄,不久便枯死,并从下部的叶顺次波及到上部的叶。病情急剧发生的时候,从下部叶至茎长的一半以上的地方会完全枯死。在旧病斑的部位则散生着黑色的微小粒状物。 Victims and diagnosed leaves were killed. At first, there were irregular spots of brownish brown spots, but when it rose, it enlarged to brown or even dark brown spots that were round, oval, irregular, etc. The shape of the lesion varies depending on the species. In addition, limited by the veins, and sometimes become fan-shaped, sometimes showing tiny spots together. When a large number of lesions appear, the leaves warp, and yellow around the lesion, soon died, and from the lower leaves sequentially spread to the upper leaves. When the disease occurs rapidly, from the lower leaves to more than half the length of the stem will be completely dead. In the old lesion site is scattered with black small particles.