Abstract

GUSMAO, Marcos Rafael; PICANCO, Marcelo; LEITE, Germano L.D.  and  MOURA, Marcelo F.. Selectivity of insecticides to predators of aphids. Hortic. Bras. [online]. 2000, vol.18, n.2, pp. 130-133. ISSN 0102-0536.  http://dx.doi.org/10.1590/S0102-05362000000200011.

The selectivity of cypermethrin, dichlorvos, diazinon, ethion, fenitrothion, matathion, methamidophos, methyl parathion, permethrin, pirimicarb, and vamidathion to adults of Cycloneda sanguinea (L.) and Eriopis connexa (Germ.) (Coleoptera: Coccinellidae) was studied. Tomato leaves were submerged in insecticide solution at recommended rate for controlling Myzus persicae (Sulzer) and Macrosiphum euphorbiae (Thomas) in tomatoes. The effect of insecticides, doses, predator species, and sex of C. Sanguinea in insecticide selectivity was evaluated. Pirimicarb and vamidathion were the most selective insecticides for C. sanguinea followed by ethion and dichlorvos (3.2, 6.7, 49.7, and 52.5% mortality, respectively). Pirimicarb was the most selective insecticide for E. connexa, followed by ethion and cypermethrin (2, 71.3, and 81.9% mortality, respectively). Males of C. sanguinea were more tolerant to ethion (33 and 66.5% mortality, respectively) and permethrin (61 and 100% mortality respectively) than females. Permethrin toxicity to E. connexa and ethion toxicity to C. sanguinea females were lower when those insecticides were applied at half dose (74.4 and 25% mortality, respectively) than when they were applied at their full dose (100 and 66.5% mortality, respectively).

Keywords : Cycloneda sanguinea; Eriopis connexa; tomato; pirimicarb; vamidathion.