[Comparacion de tres metodos diferentes de laboratorio y un ensayo de campo para determinar los efectos secundarios de pesticidas en Trichogramma cacoeciae]
Autor:Hassan, Sherif A.
The side effects of 139 pesticides on Trichogramma cacoeciae using three different types of laboratory test methods was studied. The combination of tests used included: (a) initial toxicity test on adult parasites (susceptible life stage), (b) direct spray of parasites pupa within host eggs (less susceptible life stage) and (c) duration of harmful activity (persistence) on adults. The combination was chosen to include two different developmental stages of the natural enemy that greatly vary in their susceptibility as well as in their vulnerability to pesticidas. The persistent test show the duration of the harmful activity and help to asses the impact of the chemical. In addition, the initial toxicity of 9 pesticides on Trichogramma adults was compared using laboratory and semi-field tests. The results showed that the preparations greatly differ in their initial toxicity as well as in their persistence. 28 insecticides/acaricides, 10 fungicides, 7 herbicides and plant growthregultors were harmful to the adult parasite but harmless to moderately harmful to the Trichogramm-pupa within the host eggs.18 insecticides/acaricides, 5 fungicides, 6 herbicides and growthregultors were harmful in the initial toxicity test but were short-lived to moderately persistent and therefore are much more useful for use in integrated control. Short lived preparations are likely to have much less impact on the natural enemy than persistent ones. The experiments to compare the initial toxicity in laboratory and semi-fields tests showed very little differences. This can be attributed to the similar mode of exposure in these tests