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在目前褐稻虱综合防治措施中,药剂防治是主要手段,所以正确掌握和应用防治策略,是提高防效和控制为害的关键。药剂防治策略一般五代(我省部分地区称三代、江苏称四代)褐稻虱是全年发生量最大的世代,也是晚稻的主要为害世代。在药剂防治中,是把重点放在五代,还是放在它的上一代(四代)?我们认为应根据具体情况确定。据试验,在一般发生情况下,于五代若虫开始突增期后3—5天,用杀螟粉加稻瘟净等药剂防治一次,防效达77.9—96.6％,如采用滴滴涕加乐果,防效更好。在早发年,治好五代,还有控制六代的作用。但大发生田块,五代褐稻虱常呈突发性,在若虫开始突增期前后,虫口密度可在数天内增长近10倍,每亩达数百
In the current comprehensive control measures of brown planthopper, chemical control is the main means, so the correct control and application of control strategies is the key to improving control efficiency and control. Pharmacy control strategy generally five generations (in some parts of our province, said the third generation, Jiangsu said the fourth generation) Brown rice louse is the annual generation of the largest generation, but also the main damage to the late rice generations. In the prevention and treatment of pesticides, is it put emphasis on the fifth generation or the previous generation (fourth generation)? We think it should be determined according to the specific circumstances. According to the test, in the general case, 3-5 generations after the nymphs of the 5th generation started to emerge, the control effect was reached to 77.9-96.6% with the control agent such as the rice borer and the rice blast, etc. If DDT plus dimethoate was used, Better control effect. In the early years, cure five generations, as well as the role of controlling six generations. However, the occurrence of large plots, the brown planthopper of the Five Dynasties is often sudden, in the nymphs before and after the sudden increase in population density in a few days can be increased nearly 10 times per acre up to hundreds