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1997～ 1999年调查研究表明 ,马铃薯瓢虫在陕北一年发生 2～ 3代 ,第 3代为局部世代 ;夏薯药剂防治适期在 5月中旬 ,秋薯在 7月中旬～ 7月下旬。防治适期内喷药可获得良好的灭虫保产效益
The investigation and research from 1997 to 1999 showed that the potato ladybug occurred 2-3 generations a year in northern Shaanxi and the third generation was a local generation. The control of sweet potato was suitable in mid-May and late autumn in mid-July to late July. Control during the spraying can get good pest control efficiency