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一、引言杂草在农业生产上造成的损失很大,不仅降低农作物的产量与品质,而且成为多种多样病虫害的媒介。美国1930年统计,其全国每年因杂草为害平均最少损失450万美元,而根据最新的资料,其每年损失甚至超过5亿美元,这个数字比病虫害所造成的损失要大许多倍。
I. INTRODUCTION Weeds have caused great losses in agricultural production, which not only reduce the yield and quality of crops but also serve as a medium for a wide range of pests and diseases. According to statistics from the United States in 1930, the average annual loss due to weeds in the country is at least 4.5 million U.S. dollars. According to the latest data, it even losses more than 500 million U.S. dollars each year. This figure is many times larger than the losses caused by pests and diseases.