Sociobiology (Jan 2014)
Selectivity of Old and New Insecticides and Behaviour of Vespidae Predators in Coffee Crop
Abstract
Organophosphates are old agrochemicals that are toxic for wasps (Vespidae) that are predators of insect pests. However, chlorantraniliprole is the first insecticide produced from the new anthranilic diamide class, which binds to ryanodine receptor modulators. This study uses chlorpyrifos, triazophos, pyridaphenthion and new chlorantraniliprole insecticides that have not yet been extensively tested for effects on non-target organisms. Adults of the predatory wasps were exposed to concentrations of organophosphate inseticides and the most toxic was used for a behavior test. The trial area, located in the Rio Paranaíba, Minas Gerais, received two treatments: with insecticide and without insecticide. Chlorpyrifos, the most toxic insecticide, was used in the dose of 1.5L/ha. In order to evaluate the predation, the number with predation action (injuries made by the wasps) in the leaves were accounted. Behavior activities collect of nine colonies Protonectarina sylveirae, Brachigastra lecheguana, Polybia sp. and Polistes versicolor works were quantified. All colonies were in the adult phase. The colonies were observed by 12h, from 6:00 a.m. to 6:00 p.m. The number of wasps that leaved and returned to the nest, type of sources collected (glucidic foods, prey larvae, matherial for construction of the nest). The most toxic insecticide was chlorpyrifos and the most selective was chlorantraniliprole. The species and frequencies of wasps predator were: P. sylveirae (71.50%), B. lecheguana (12.00%), Polybia sp. (7.00%) and P. versicolor (1.00%). Chlor-pyrifos presented not selective and changes in the behavior to the predatory wasps.
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