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自五十年代中后期开始,耕作制度的改革进展较慢,同时又大面积推广药剂防治,螟害率曾压低到1%左右。七十年代初,受极“左”思潮的影响,耕作制度改革加快,逐渐打破了原有农田生态体系,水稻螟虫生物学特性发生了一些变化,因而也导致了为害情况的变化。凡水稻栽培制度复杂的地区,螟虫大发生的频率增多,危害也趋严重。因此,目前螟虫仍是
Since the mid and late 1950s, the progress of the reform of the farming system has been relatively slow. At the same time, large-scale promotion of pharmaceutical control has been achieved. The rate of stem borer has been reduced to about 1%. In the early 1970s, under the influence of the “Leftist” trend of thought, the reform of the farming system was accelerated and the original farmland ecosystem was gradually broken down. Some changes in the biological characteristics of rice stem borers were also observed, which led to changes in the situation of damage. Where the rice cultivation system is complicated, the occurrence frequency of stem borers will increase, and the damage will also become more serious. Therefore, the current stem borer is still