Selectivity of pesticides used in rice crop on Telenomus podisi and Trichogramma pretiosum

Abstract

Telenomus and Trichogramma species stand out as agents for the biological control in rice crops, and the main strategy for preserving them is the use of selective pesticides. This study aimed at evaluating the toxicity of pesticides used in irrigated rice crop on Telenomus podisi Ashmead (Hymenoptera: Platygastridae) and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). Adults of these parasitoids were exposed to dry residues of pesticides, in a completely randomized experiment, with 25 treatments (24 pesticides + control) and four replications. The insecticides clorantraniliprole, flubendiamide and diflubenzuron and the biological insecticides based on Beauveria bassiana and Metarhizium anisopliae were harmless to T. podisi and T. pretiosum. The harmless herbicides were: 2.4-D amine, profoxydim, quinclorac, ethoxysulfuron and saflufenacil. The fungicide epoxiconazole + kresoxim-methyl was also harmless to these two biological control agents. Therefore, these pesticides are indicated for the integrated pest management, in flooded rice areas.