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番茄叶毒病又称“黑毛”,是保护地番茄的重要病害。该病流行速度快,常常在短期内暴发成灾,一般损失20—30%,严重时可达50—80%。 一、症状 叶霉病以叶片发病为多,但茎、花和果实也可受害。叶片发病初期,叶背面出现椭圆形或不规则形淡绿色或浅黄色退绿斑,随后病斑上长出灰黄色至黄褐色绒状霉层。叶正面表观为淡黄色退绿斑,边缘不清晰。发病严重时,病斑连片,叶片干枯卷曲,直至病株枯死。一般叶片发病由下部老叶向上发展,而中部叶最易感病。嫩茎及
Tomato leaf disease, also known as “black hair”, is an important disease in tomato fields. The prevalence of the disease is rapid and is often catastrophic in the short term, with losses of 20-30% and up to 50-80% in severe cases. First, the symptoms of leaf mold disease leaves more, but stems, flowers and fruits can also be victims. Early leaves, oval or irregular shape on the back of the leaves pale green or light yellow green spots, followed by the growth of gray spots to yellowish brown tomentose mold layer. The apparent appearance of the leaves is pale yellow retrogressive green spot, the edge is not clear. When the disease is serious, the lesion contiguous, the leaves curl dry, until the diseased plants die. The general development of the leaves from the lower part of the old leaves upward, while the middle leaves the most susceptible to disease. Stems and