摘要
1980—1986年,通过田间试验,研究了棉蚜对棉花的危害损失,平均单株蚜量(x)与籽棉产量损失率(y)的关系:出苗至3片真叶期为y=-38,574+11.645Inx;4—6片真叶期为y=-49.633+11.232lnx;成株期(伏蚜)为y=-28.802+5.465lnx.在经济允许损失为1%左右时,三个生育期的棉蚜防治指标分别为平均每株30—50头,每株80头左右,和每株(3片叶)200头左右.经生产示范,执行本指标可减少药剂防治2—3次,有明显的经济效益和生态效益.
Studies were carried out in Henan province in 1980-1986 to determine the loss caused by aphids on yield of cotton. Six-seven grades of aphid number were established in field trials by using insecticide spray at different stages of cotton growth. The subsequent development of regression equation, the exact economic threshold for cotton aphid on cotton is given. The calculated economic thresholds were 30-50 aphids/plant for the stage before three-leaves stage of cotton, 80 aphids/plant for the 4-6 leaves stages and 200 aphids/plant(three leaves)more or less for maturity stage of cotton,respectively.Aphid number accumulation on developing stage of cotton showed negative linear relationships with the yield, and insecticides should be applied before population reached critical level of aphids at different growth stage of cotton.
出处
《华北农学报》
CSCD
北大核心
1989年第3期60-66,共7页
Acta Agriculturae Boreali-Sinica
关键词
棉蚜
虫害
防治指标
棉花
Cotton aphid
Damage
Economic threshold
