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昆明地区海拔1890公尺,年平均气温15.1℃,属一季中稻区。水稻螟虫主要有二化螟和三化螟两种,常混合发生,交替为害,为两代螟害区。过去,对三化螟的发生规律、测报技术和防治方法,曾进行过一些研究,提出了应用三化螟蛹发育分级进行简化预测的方法,掌握防治适期,能将螟害率压低到1％以下。近几年来,由于水利条件的改善,水稻栽插节令逐年提早,春耕晒垡和灌水时期亦相应提前,从而消灭了大量越冬螟虫,螟虫种类亦随之发生变动,三化螟数量减少,二化螟相对上升,不仅第一代枯心苗主要是二化螟为害所致,第二代二化螟为害造成白穗日
Kunming, 1890 meters above sea level, the annual average temperature of 15.1 ℃, is a mid-season rice area. Rice stem borers are mainly three stem borer and three borer, often mixed occurrence, alternating damage for the two generations of pest damage area. In the past, on the occurrence of the rice stem borer, reporting techniques and methods of prevention and control, have conducted some research, put forward the application of the developmental stages of the Chilo suppressalis pupae to simplify the prediction method to master the control of fitness, the pest rate can be reduced to 1 %the following. In recent years, due to the improvement of water conservancy conditions, planting seasonings of rice have been accelerated year by year, and spring plowing and irrigation have also been advanced ahead of schedule. As a result, a large number of wintering stem borers have been eliminated, and the number of stem borers has also changed. Borer relative rise, not only the first generation of dead heart seedlings is mainly caused by Chilo suppressalis second damage caused by rice stem borer White Shizhong