灰霉病,一般认为是一种寄生力较弱的病害。以往在北方春天较难找到标本。然而,随着保护地蔬菜的发展,其为害性愈来愈大。据调查,目前在北京市海淀、朝阳、丰台三个区均有不同程度的发生,某些温室黄瓜的被害瓜率可达46.15％,番茄被害果率达24％。1980年春季多阴天,气温低,灰霉病较以往发生重。 症状:黄瓜受灰霉病为害,多以开败的花上开始,使花腐烂,并长出淡灰褐色的霉层。进而向瓜条侵入,使脐部腐烂,并迅迷向上发展。幼瓜被害变软、萎缩、腐烂,表面密生霉层;较大的瓜被害时,组织先变黄,再生白霉,然后霉层转变成淡灰色。被害瓜轻者生长停止,端部腐烂,重者全瓜腐烂。叶片被害一般是由掉落的烂花附着在叶 Botrytis is generally considered to be a parasitic weaker disease. In the past in the northern spring more difficult to find specimens. However, with the development of protected vegetables, its harmfulness is getting bigger and bigger. According to the survey, at present, Haidian, Chaoyang and Fengtai districts in Beijing all have different degrees of occurrence. In some greenhouse cucumbers, the rate of melon culling up to 46.15% and that of tomato culling up to 24%. Cloudy weather in spring 1980, low temperature, gray mold occurred heavier than ever before. Symptoms: Cucumber is damaged by Botrytis cinerea, which begins with blossoming flowers, decaying flowers and growing a light gray-brown moldy layer. And then invaded the cantals, umbilical decay and rapid development. The cucumber was softened, atrophied and decayed, and the surface was mildew-dense. When the larger melon was killed, the tissue turned yellow and the white mold was regenerated, and the mildew layer turned into light gray. Victims of light melon growth stopped, end decay, severe decay of the whole melon. Blade damage is generally caused by falling burnt-out leaves attached to the leaves