Efficacy of Methoprene for Control of Five Species of Psocids (Psocoptera) on Wheat, Rice, and Maize

The insect growth regulator methoprene was evaluated for control of Liposcelis bostrychophila Badonnel, Liposcelis decolor (Pearman), Liposcelis entomophila (Enderlein), Liposcelis paeta Pearman (Psocoptera: Liposcelididae), and Lepinotus reticulatus Enderlein (Trogiidae) at application rates of 1, 5, and 10 ppm on maize, wheat, and rice. Methoprene did not completely suppress progeny production during the 40-day test period, but did cause a significant reduction in adult progeny in all psocid species at the application rates of 5 and 10 ppm. At I ppm, numbers of adults were reduced for all species on wheat and maize, but only for L. paeta on rice. Nevertheless, the numbers of nymphs present after 40 days generally were not reduced, relative to the controls. Methoprene applied at rates of 1 to 10 ppm to stored grain would not provide adequate control of psocids.