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苹果白粉病的流行条件与防治对策苹果白粉病是发生时间长难以彻底防治的严重病害之一。近几年来更有逐渐加重的趋势。此病主要为害叶片和新梢,也为害花、幼果和芽。新梢初次发病率高达30%-60%,以致新梢停止生长,并陆续干枯,对树势及产量影响极大。一、流行条件...
Apple powdery mildew epidemic conditions and prevention and control measures Apple powdery mildew is one of the serious diseases that take a long time to completely prevent and cure. In recent years, there has been a gradual increase in the trend. The disease is mainly affected leaves and shoots, but also for flowers, young fruit and buds. The initial incidence of shoots as high as 30% -60%, resulting in new shoots to stop growing, and gradually dried up, on the tree vigor and yield a great impact. First, the prevalence of conditions ...