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杨圆蚧是近年来我国北方地区杨树人工林毁灭性害虫之一。主要危害中东杨,小叶杨,发生区的树干上部,虫口密度每平方厘米平均达36.5头.1年发生1代,若虫期雌雄均各为2龄,成虫于5月中旬羽化,雌雄性比为1:0.3。此文研究了各虫期起迄日期、发育进度、发育所需要天数,从而可以对成虫发生盛期、产卵盛期、初孵若虫盛期进行预报。杨圆蚧重要天敌红点唇瓢虫日平均捕食量为31.9头(成虫);蚜小蜂寄生率平均为20.5％。用化学药剂石硫合剂及氧化乐果防治初孵若虫,校正死亡率分别为95.2％及76.3％。
Yang Kuwana is one of the devastating pests of poplar plantations in northern China in recent years. The main damage to the Middle East poplar, Populus, the occurrence of the upper part of the trunk, insect population density per square centimeter average of 36.5 1 generation occurred in 1 generation, nymphs were male and female for each 2 instar adult emergence in mid May, male to female ratio 1: 0.3. In this paper, the starting and ending dates of each worm stage, developmental progress, days of development are studied, which can predict the peak period of adult worms, the peak of spawning and the peak of newly hatched nymphs. The average daily predation amount of the dominant predatory red spot ladybird of Populus deltoides was 31.9 (adult). The average parasitism rate of the insect was 20.5%. With the chemical agent lime sulfur mixture and omethoate control of newly hatched nymphs, the corrected mortality rates were 95.2% and 76.3%.