褐飞虱在太湖单季稻区的迁入、繁殖和为害

Immigration, reproduction and damage of Nilaparvata lugens in single season rice region of Taihu

通过分析太湖单季稻区褐飞虱大发生年份的田间虫量,灯下诱虫量,定点调查田块的水稻品种和播种期,发现太湖单季稻区褐飞虱的迁入主峰期是7月10～25日.20世纪90年代后是7月10～20日,灯下7月5～24日的迁入峰可作参考;迁入峰只有1个,若遇水稻分蘖中、后期,则增殖1代就可进入主害代,若遇水稻分蘖前期,则需增殖2代才能进入主害代;从增殖代短翅型成虫高峰到主害代低龄若虫高峰的增值是主要的,起决定作用,从迁入主峰到增殖代短翅型成虫高峰的增值起辅助作用,处于分蘖后期至齐穗期的增殖代是主害代暴发的关键,盛夏高温对抑制单季稻褐飞虱的发生作用不大.随着农艺措施的改变,单晚发生期由8月中、下旬推迟到9月25～30日,褐飞虱的发生已进入了低迁入,高增长阶段.

s： Based on the analysis of field quantity, trapping quantity under lamp, rice variety and growing stages in the year of outbreak of Nilaparvata lugens in single season rice in Taihu area, major immigration peak period of N. lugens was from 10^th to 25^th July which used to be 10^th/to 20^th July in 90 s of 20^th century, and the period of it under lamp from 5th to 24^th July could be taken as reference. As single immigration peak matched middle and late period of tillering, it come major damage period after reproducing one generation. As single immigration peak matched the early period of tillering, it come major damage period after reproducing two generations. Reproduction from peak of short wing adults in reproduction generation to peak of low instar nymph in major damage generation played crucial role, and reproduction from peak of immigration to peak of short wing adult in reproduction generation played assistant role. Reproduction generation from late tillering stage was critical for outbreak of major generation. High temperature showed little inhibition against N. lugens in single season rice. Because of the changes of agricultural measures, the occurrences of N. lugens in single season late rice delayed from middle and late August to 25^th to 30^th of September. And occurring characteristics of N. lugens turned to be low immigration and high increasing.