一、菊花黑斑病 (被害与诊断) 叶被害。起初,出现不规则的褐色的小斑点,但逐渐便扩大成为圆形、椭圆形、不正形等的褐色乃至黑褐色的病斑。病斑的形状,因品种不同而有差异。另外,受叶脉限制,有时成扇形,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,而且病斑周围发黄,不久便枯死,并从下部的叶 First, chrysanthemum black spot disease (victims and diagnosis) leaves were killed. At first, irregular brownish spots appeared, but gradually expanded into roundish, oval, irregular shaped brown or even dark brown spots. The shape of the lesion varies according to the variety. In addition, limited by the veins, sometimes 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