采用大田笼罩接虫法研究短额负蝗为害烟草经济损失结果表明，烟株上虫量越大，中上等烟叶下降比率和经济损失越大。单株虫量１、２、４头造成的中上等烟叶下降比例分别是６．０７％、２６．２９％、３９．７２％，经济损失率分别为１４．１７％、３１．８５％、４８．０１％；底叶、下二棚叶、腰叶、上二棚叶、顶叶受害指数分别是１．３９、１３．５４、１８．０６、２５．００、１４．８２。计算出了经济阈值，确定短额负蝗防治指标为６头／１００株 The results showed that the larger the amount of insects on tobacco plants, the lower the ratio of middle and upper leaves and the greater economic loss of tobacco. The proportion of middle and upper leaves caused by 1, 2 and 4 insects per plant was 6.07%, 26.29% and 39.72%, respectively. The economic loss rates were 14.17% and 31.85% respectively, 48.01%; bottom leaf, the next two shed leaves, lumbar, leaf shed on the second floor, the top leaf damage index was 1.39,13.54,18.06,25.00,14.82. Calculated the economic threshold, to determine the indicators of prevention and treatment of short-negative locust 6/100