摘要
研究了春直播棉1～3叶期、4～7叶期和伏蚜期不同卷叶株率与棉花产量损失率的关系,组建了它们的相关式。分析了不同棉花产量水平下的各期棉蚜的经济动态防治指标。提出亩产75～85kg 上述各期棉蚜的防治指标分别为卷叶株率8%、20%和10%。
Cotton aphis is the most destructive pest of cotton at the early and middle growth stages of cotton in Shandong Province. The damage caused by cotton aphis and its control criteria were studied during 1983-1985 in Pingyuan, Dezhou, Zhucheng and Linqing counties.These experiments were conducted in field plots as well as in the fields. We used the percentage of curly-leaf plants as the index of control criteria during stages 1-3 leaves, 4-8 leaves and 'summer aphid', because this index not only can indicate the relativity with the aphid number correctly, but also save labour to count the aphis.The result obtained has showed that the percentage of curly-leaf plants and the percentage of yield reduction at three cotton growth stages mentioned above can be expressed as y=20.021e^(-809287/x),y=19.925e^(13.3779/x),y=23.272e^(-12.2155/x) According to the cost and the efficiency of control, the yield and the price of ginned cotton, and the critical factor, we consulted the yield level of the cotton crop in Shandong Province (120-150 jin per mu) and used these regression equations to account these control criteria as follows: the percentage of curly-leaf plants 4-5% at stages 1-3 leaves, 7-8% at stages 4-8 leaves and 'summer aphid'.
出处
《山东农业大学学报（自然科学版）》
CSCD
1993年第2期183-187,共5页
Journal of Shandong Agricultural University：Natural Science Edition
关键词
春直播
棉蚜
防治
棉花
cotton aphid
percentage of curly-leaf plants
percentage of yield-reduction
control criteria
