Tolerance of the planarian Dugesia tigrina (Tricladida: Turbellaria) to pesticides and insect growth regulators in a small-scale field study.

Two insect growth regulators, methoprene and a benzyl-1,3,benzodioxole (J-2931), had no detrimental effects on Dugesia tigrina under field conditions. Three other compounds, resmethrin, temephos, and cyromazine, had only minimal effects. Asexual multiplication among these planarian predators exceeded 68% when combined with Culex quinquefasciatus larvae and methoprene at different concentration levels. Also, this combined treatment with D. tigrina and methoprene resulted in high level (98.9%) reduction of Cx. quinquefasciatus populations through the 7-wk field study.