Seletividade de produtos fitossanitários utilizados na cultura do pessegueiro aos predadores Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) e Coleomegilla quadrifasciata (Schöenherr, 1808) (Coleoptera: Coccinellidae)

Abstract

In the peach crop, the chemical control is the most used strategy in the management of pest insects, however, alternative control measures, such as biological control, based on Integrated Pest Management (IPM), must be prioritized. In this sense, side effects studies of natural enemies can generate important information so that an association of control methods can be made feasible. In this sense, the objective of this work was to evaluate the side effects of nine pesticides used in peach orchards on Chrysoperla externa and Coleomegilla quadrifasciata using the methodology proposed by the International Organization for Biological and Integrated Control of Noxious Animals and Plants (IOBC). In the bioassays eggs and pupae were carried out direct applications. Bioassays with larvae and adults consisted of exposure of insects to dry residues of sprayed pesticides on glass slabs. In the bioassays with eggs and pupae, larval emergence reduction and reduction in adult emergence, respectively, and subsequent fertility and fertility evaluation in surviving adults were evaluated. In larval bioassays the duration of developmental stages, mortality, and fertility and fertility rates of surviving adults. In the adult bioassays, the accumulated mortality at 24, 72 and 120 hours after exposure of the insects to the residues of the phytosanitary products was evaluated. The side effects was calculated by the total effect for all phases, where the pesticides were classified as innocuous (<30%), slightly harmful (30- 79%), moderately harmful (80-99%) and harmful (> 99 %), recommended by IOBC. It was concluded that for C. externa all phytosanitary products showed to be innocuous (class 1) for eggs, however, on the pupal phase, abamectin (80) and copper + calcium (1%) were slightly harmful (class 2). For the egg phase of C. quadrifasciata fenitrothione (100) it was moderately toxic (class 3). Abamectin (80), deltamethrin (40) and malathion (150) were slightly harmful (class 2), the other products were innocuous (class 1), and for the pupae phase the products abamectin (80), fenitrothion (100) and malathion (150) were toxic (class 4), and the other products were innocuous (class 1) to C. quadrifasciata. The ladybug C. quadrifasciata was more sensitive than C. externa to all pesticides tested in the egg and pupal phases. The products Azadirachtin (1%), chlorantraniliprole (14) and copper + calcium (25% + 10%) were innocuous (class 1) to the larval phase of C. externa. The abamectin (80) and copper + calcium (1%) products were slightly harmful (class 2) to the predator at this stage. Deltamethrin (40), fenitrothione (100) malathion (150) and sulfur + calcium (3.5 ° Ba) were harmful (class 4) to larvae of this insect. In the adult phase of C. externa the Azadirachtin (1%), chlorantraniliprole (14) and copper + calcium (25% + 10%) were innocuous (class 1), and abamectin (80) was slightly harmful (class 2). The products deltamethrin (40), fenitrothion (100), malathion (150), copper + calcium (1%) and sulfur + calcium (3.5 ° Ba) were harmful (class 4) to C. externa adults. For the larval phase of C. quadrifasciata chlorantraniliprole (14) was innocuous (class 1). The product sulfur + calcium (3.5 ° Ba) was slightly harmful (class 2), while the product copper + calcium (25% + 10%) was moderately harmful (class 3), the other products were harmful (class 4).In the adult phase of C. quadrifasciata the products Azadirachtin (1%) and copper + calcium (25% + 10%) were innocuous (class 1). Chlorantraniliprole (14), deltamethrin (40) and copper + calcium (1%) were slightly harmful (class 2). Abamectin (80), fenitrothione (100) malathione (150) and sulfur + calcium (3.5 ° Ba) were harmful (class 4).