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近年来由于农业技术的改进和品种(组合)不断更换,致使水稻害虫种群数量出现一些新的变化.如以往间歇发生的稻飞虱、稻纵卷叶螟,从七十年代起连续数年大发生.据我省1975年四个地区不完全统计,褐飞虱发生面积达700余万亩,虽经防治仍损失稻谷两亿多斤.八十年代起,据1983年全省不完全统计,白背飞虱发生面积为600余万亩,发生严重的田块(制种田) 颗粒无收.二化螟明显加重.稻纵卷叶螟危害严重时,卷叶率高达80%以上.稻苞虫则在局部地区暴发成灾.
In recent years, due to the improvement of agricultural technology and variety (combination) constantly changing, resulting in some new changes in the population of rice pests, such as the previous intermittent occurrence of planthoppers, rice leaf roller, from the seventies consecutive years Occurred in 1975. According to the incomplete statistics of the four regions of our province in 1975, the area of brown planthopper occurred was more than 700 mu, although it still lost more than 200 million kilos of rice despite prevention and treatment. Since the 1980s, according to the incomplete statistics of the province in 1983, Planthopper occurred in an area of more than 600 acres, a serious field block (farming) particles no crop .S. stem borer significantly aggravated.Caproller leaf damage rate is as high as 80% .Basic worm Outbreaks in some areas.