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近十多年来,稻飞虱、稻纵卷叶螟、稻瘿蚊的发生数量相继上升,成为广东省为害水稻的重要害虫。据我们的分析,主要由下面两个因素决定的:1、水稻宽叶矮秆品种的广泛栽培,插植密度增大,肥料用量增加,从栽培条件来说有利于这几种害虫的大量发生;2、大面积不恰当的、大量而连续的施用广谱性化学杀虫剂,导致稻田各类害虫天敌数量的严重凋落,成了这些害虫大量发生的重要因素。
In the recent ten years, the number of rice planthoppers, rice leafroller and rice gall midge have all increased one after another and become important pests for rice damage in Guangdong Province. According to our analysis, mainly by the following two factors: 1, broad-leaved varieties of broad-leaved rice cultivation, planting density increased, the amount of fertilizer increased from the cultivation conditions conducive to the occurrence of these pests in large numbers ; 2, a large area is not appropriate, a large number of continuous and continuous application of broad-spectrum chemical pesticides, leading to a variety of pests in paddy fields, the number of serious natural enemies of litter, has become an important factor in the large number of these pests.