Seletividade de agrotóxicos utilizados na cultura da soja aos parasitoides de ovos Telenomus podisi Ashmead, 1893 e Trissolcus basalis (Wollaston, 1858) (Hymenoptera: Platygastridae)

Abstract

Soybeans are the most produced crop in Brazil and phytosanitary problems require efficient management to guarantee the sustainability of the productive system, for this the use of agrochemicals is the most used strategy for the control of soybean pests, weed and diseases.Chemical control, however, can affect egg parasitoids of phytophagous bugs of the crop, being the main parasitoids Telenomus podisi Ashmead, 1893 and Trissolcus bassalis (Wollaston, 1858) (Hymenoptera: Platygastridae). Thus, the objective of this study was to avaluate 15 agrochemicals used in the soybean crop for these two adult and immature egg parasitoids in pre and post parasitism tests. The bioassays were carried out according to the “International Organisation for Biological and Integrated Control of Noxious Animals and Plants” (IOBC) nine insecticides, four fungicides and two registered herbicides were tested for soybean crop. The insecticides Belt® (flubendiamide), Dimilin 80 WG® (diflubenzuron), Dipel PM® (Bacillus thuringiensis) and Match EC® (lufenuron) were innoxious to both adult and immature parasitoids (pre and post parasitism tests). The insecticides Connect® (imidacloprid + beta-cyfluthrin), Decis 25 EC® (deltamethrin), Engeo Pleno® (lambda-cyhalothrin + thiamethoxan), Orthene 750 BR® (acephate) and Sumithion 500 EC® (fenitrothion) were harmful to both adult parasitoids affecting parasitism in the immature phase only in pre-parasitism tests, in which the products were classified as slightly harmful to T. podisi but moderately harmful to T. basalis, except for Orthene 750 BR® (acephate) which was classified as slightly deleterious.The fungicides Authority® (azoxystrobin + flutriafol), Fox® (trifloxystrobin + prothioconazole), Opera®Ultra (pyraclostrobin + metconazole) and Sphere Max® (trifloxystrobin + cyproconazole) were innoxious to adults of T. podisi but were not to T. basalis, for which they were classified as slightly deleterious. However only Opera®Ultra (pyraclostrobin + metconazole) reduced the parasitism of T. basalis in pre-parasitism, being slightly harmful to this parasitoid. The herbicides Finale® (glufosinate ammonium salt) and Glifosato Atanor® (salt of isopropylamine) were innoxious to parasitoids in both adult and the immature phase (pre and post parasitism tests).