Control of Bemisia tabaci with insecticides
Recently, Bemisia tabaci (EPPO A2 pest) has become a major pest in vegetable fields in Egypt. Studies were undertaken to compare the impact of different insecticides in low-rate and normal applications on populations of B. tabaci and their associated parasites and pretadors on cucumber.
Eggs of the cotton whitefly proved to be less susceptible to insecticides with a maximum reduction of 66%. Larvae and pupae treated with ethiofencarb, diafenthiuron and chlorpyrifos methyl were reduced by 67%, 50% and 68% (for larvae) and 68%, 69% and 75% (for pupae), respectively. However, all tested insecticides and dosage rates caused severe suppression of emergence of adult parasitoids as well as decreasing longevity of adult parasitoids.
Sources
El-Ghany, A.; El-Sayed, M.; El-Ghar, G.E.S.A. (1992) The influence of normal and low-rate application of insecticides on populations of the cotton whitefly and melon aphid and associated parasites and pretadors on cucumber.
Anzeiger für Schädlingskunde, Pflanzenschutz, Umweltschutz 65, 54-57.