Toxicity of insecticides used in coffee crops to the predator Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), sublethal, and intergenerational effects

Abstract The use of selective insecticides is essential to harmonize chemical and biological control in coffee crops. This study evaluated the selectivity of chlorpyrifos, cartap hydrochloride, pyriproxyfen, profenofos/lufenuron, fenpropathrin, and zeta-cypermethrin toward pupae and adults of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), a key predator of mealybugs in coffee crops. Topical bioassays were conducted on pupae and adults (24-h-old) under laboratory conditions, and reproductive parameters of the offspring originating from treated individuals were also assessed. Fenpropathrin and zeta-cypermethrin reduced pupal survival without affecting pupal duration. All insecticides reduced adult survival, with fenpropathrin, zeta-cypermethrin, and cartap causing the lowest survival rates. Offspring fecundity was reduced by fenpropathrin and zeta-cypermethrin when pupae were treated, and by fenpropathrin, zeta-cypermethrin, and cartap hydrochloride when adults were exposed. Egg viability was affected differently: offspring from treated pupae showed reduced hatching rates only with fenpropathrin and zeta-cypermethrin, whereas offspring from treated adults had lower egg viability after exposure to chlorpyrifos, cartap, profenofos/lufenuron, and fenpropathrin. Chlorpyrifos, pyriproxyfen, and profenofos/lufenuron were harmless to the pupae. Pyriproxyfen was the only compound classified by the IOBC as harmless (Class 1) to both life stages, while fenpropathrin was considered harmful (Class 4) to adults, and the other insecticides were classified as slightly harmful (Class 2). These results indicate that insecticides classified as Class 1 or 2 are compatible with C. montrouzieri , which supports their potential integration into integrated pest management programs in coffee agroecosystems.