Effect of insecticides on boll weevil populations and beneficial arthropods on cotton fields using trap crop residues

Abstract

This research was conducted in Jaboticabal, SP, Brazil, during the season of 1990/91. The purpose was to study the efficiency of insecticide for boll weevil (Anthonomus grandis Boheman) control by using a trap crop residue. The statistical design followed the randomized blocks with four treatments and four replications. The treatments were: 1) endosulfan 0,7 kg AI/ha; 2) deltamethrin 0.015 kg AI/ha; 3) methyl parathion 0.6 kg AI/ha; 4) check (no insecticide). The evaluations were made before and at 1 and 7 days after the sprayings. The results showed that: a) deltamethrin was efficient for boll weevil control; b) endosulfan showed to be selective to arthropod predators associated to trap crop residues left after the harvest for boll weevil attraction and control; c) endosulfan and parathion were medianly efficient; d) parathion and deltamethrin showed to be little selective.