黑斑病:多发生在苗期,植株受害后,叶片、叶柄产生小黑斑,温度高时病斑扩展为灰褐色圆形病斑,直径在5~10毫米,轮纹不明显,且薄而易破,造成叶片穿孔。防治方法:一是实行合理轮作,种植密度适宜,通风透光良好;二是于发病初期用75%百菌清可湿性粉剂500~600倍液,或50%速克灵可湿性粉 Black spot: Occurred in the seedling stage, plant damage, leaf, petiole produce small dark spots, high temperature lesions expanded to brownish brown spot, diameter of 5 to 10 mm, the wheel pattern is not obvious, and thin The easy to break, causing the leaves perforated. Prevention methods: First, the implementation of a reasonable rotation, planting density appropriate, good ventilation and ventilation; the second is the early onset of 75% chlorothalonil WP 500 ~ 600 times, or 50%