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为了搞清上海郊区高温季节棉蚜为害对棉花产量的影响,从而提出防治指标。作者在1979、1980及1984年,采用小区与大田试验相结合的方法对此进行了研究。结果表明:减产程度与单株蚜量成正相关,y=1.1850X-0.1344,r=0.98(其中y为产量损失机率值;x为虫口密度对数值)。t检验表明,单株蚜量达3,500头,将使单株减产21.90％,有显著差异。引起最低显著差异的减产率为19.3％,其相应的单株蚜量为3,286头。所以,这3,286头蚜量可作为引起减产的阈值蚜量。通过计算,单株蚜量为3,286头以上的为害株达到12％时的为害株率,即为本研究提出的伏蚜防治指标。
In order to find out the impact of the cotton aphid damage caused by the hot season in Shanghai suburbs, the control index was put forward. In 1979, 1980 and 1984, the author studied the method using a combination of plot and field experiments. The results showed that the degree of yield reduction was positively correlated with the amount of aphid per plant, y = 1.1850X-0.1344, r = 0.98 (where y is the yield loss probability value and x is the population density logarithm). t test showed that the amount of aphids per plant reached 3,500 heads, will make the plant yield 21.90%, a significant difference. The yield reduction resulting in the lowest significant difference was 19.3% and the corresponding individual aphid population was 3,286. Therefore, the 3,286 head aphids can be used as the threshold aphid causing the reduction. According to the calculation, the damage rate of plants with the number of aphids per plant of 3,286 or more reached 12%, which is the control index of the aphids proposed in this study.