Insect Growth Regulators: Some Effects of Methoprene and Hydroprene on Productivity of Several Stored Grain Insects.

Abstract

The effects of two insect growth regulators on the productivity of Rhyzopertha dominica, Sitophilus oryzae and S. granarius were studied by exposing insects to wheat treated with methoprene (isopropyl 11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate) or hydroprene (ethyl 3,7,11-trimethyldodeca-2,4-dienoate) at concentrations of 1, 5, 10 and 20 ppm. Parental adult mortality was generally higher on wheat treated with methoprene than with hydroprene, and this effect was usually enhanced under unventilated conditions. The productivity of the three species was markedly reduced, in some instances suppressed, under unventilated conditions, whereas only R. dominica productivity was depressed under ventilated conditions. When progeny were produced, their productivity was, in general, lower than normal.