摘要： 玉米螟危害棉株生长点和主茎后,单株产量损失28.26～88.7％,由于棉株的自我生理调节和群体补偿效应,实际损失为12.61～52.17％。测定了受害株率与产量损失率以及受害株率与百株卵块数之间的关系,拟定出不同皮棉产量水平的棉田防治指标:高产田(100kg/亩)4.9块卵/百株;中产田(75kg/亩左右)5.5块卵/百株;低产田(50kg/亩左右)6.2块卵/百株,在玉米螟严重发生年份,应适当放低。

关键词: 棉花, 玉米螟, 防治指标

Abstract: The damage and the control index of siatic corn borer in cotton fields were investigated during 1985-1988. The results showed that after the growing point and main stem of the cotton plant were injured by the corn borer,the yield could be reduced by 28.26%to 88,70%for the plant, However, the practical loss was only from 12.61%to 52,17%resulting from the self-regulation and mass compensation of the plant, According to the relationships between the percentage of infested plants and the yield loss, and between the percentage of the infected plants and the nu tuber of the egg masses/100 plants, the control indices (4.0, 5.5, 6.2 egg masses/100 plants) were determined for the different yields of cotton 0100, 75, 50kg/mu).

Key words: Cotton, Asiatic corn borer, Control index