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宜城县郑集公社金铺大队第三生产队于1974年4月27日至5月3日在2.5亩春花地里释放了3,000头七星瓢虫。据三次调查,有蚜株率和百株蚜量均大大减少。4月29日调查,有蚜株率由55%下降到15%,百株蚜量由985头减少到29头;5月15日调查,有蚜株率继续下降到7%,百株蚜量减少到22头;6月10日调查,有蚜株率再下降到2%,百株蚜量只有2头。有效防治期49天,防治效果达98.4%。而相距100米远,长势与前田相同的3.2亩春花地未放瓢虫防治,蚜虫为害严重。据调查,5月
The third production team of Jinpu Brigade, Zhengji Commune, Yicheng County, released 3,000 Qixing Ladybugs on 2.5 mu of spring blossoms from April 27 to May 3, 1974. According to the three surveys, the rate of aphid strains and the amount of aphids per plant were greatly reduced. April 29 investigation, aphid strains decreased from 55% to 15%, aphid population reduced from 985 to 29; May 15 survey, aphid plant rate continued to decline to 7%, a hundred aphids Reduced to 22; June 10 investigation, aphid plant rate dropped to 2%, the number of aphids only two. Effective prevention and control of 49 days, the control effect of 98.4%. The distance of 100 meters, the same with the Maeda 3.2 acres of spring flowers did not put ladybug control, aphids serious damage. According to the survey, in May