Effect of selected insecticides on natural enemies in cotton: laroratory studies

摘要

We evakyated the tixucutt if severak ubsectucudes (Karate, Tracer, Steward, S-1812) to selected key natural key natural enemies (green lacewing, Chrysoperla rufilabris; big-eyed bug, Geocoris punctipes; insidious flower bug, Orius insidiosus; Trichogramma pretiosum; Cotesia marginiventris) in residual assays. Chrysoperla rufilabris was affected very little by any of the insecticides ealuated. Karate and tracer were generally more toxic to the natural enemies than were the other compounds, although the degree of this difference was quite variable. Steward and S-1812 exhibited good to excellent selectivity to natural enemies, although S-1812 had some toxic effects on Trichogrammapretiosum and Orius insidiosus. Tracer exhibited marginal to good selectivity, but was quite toxic to Trichogramma pretiosum and moderately toxic to Cotesia marginiventris. Tracer is currently a valuable IPM tool because of its selectivity, but does have some toxic effects on parasitoids, at least at the rate tested here. Steward and S-1812 also hold considerable promise as IPM tools as they exhibit good levels of selectivity.