Toxicity of pesticides used in peach orchard on adults Trichogramma pretiosumThe toxicity of sixteen commercial formulations of pesticides used in peach orchard was assessed on adults of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae). The experiments were carried out using the International Organization for Biological and Integrated Control of Noxious Animals and Plants, West Palaearctic Regional Section (IOBC/WPRS) standard methodology, under laboratory conditions at temperature of 25±1ºC, relative humidity of 70±10% and 14h photophase. The tests were carried out by exposing the adult parasitoids to fresh dry pesticide film applied on glass plates and assessed for the number of eggs parasitized by T. pretiosum adult female. Reduction in capacity of parasitism of T. pretiosum female compared with the control (treated with water) was used to measure the effect of the chemical. Pesticides were then classified into four categories, according to the reduction in parasitization (IOBC/WPRS): 1, harmless (<30%); 2, slightly harmful (30-79%); 3, moderately harmful (80-99%); 4, harmful (>99%). The fungicides (g of the active ingredient/100L of water) calcium + copper (40+100), dodine (79), folpet (125), iprodion (75), mancozeb (160), mancozeb + copper oxichloride (88+60) and triforine (24) and the insecticide teflubenzuron (3.75) were considered harmless (class 1); the fungicide tebuconazol (20) and the mineral oil (800) were slightly harmful (class 2); the fungicide-acaricide sulphur (480) and the herbicide glufosinate-ammonium (200) were moderately harmful (class 3); the insecticides fenitrothion (75), malathion (200), phosmet (100) and spinosad (6) were harmful (class 4) to T. pretiosum.
Insecta; selectivity; biological control; Prunus persica L
