Field Performance of Metarhizium anisopliae Against Popillia japonica (Coleoptera: Scarabaeidae) and Listronotus maculicollis (Coleoptera: Curculionidae) Larvae in Turfgrass

Abstract

Japanese beetle, Popillia japonica Newman, and annual bluegrass weevil, Listronotus maculicollis Kirby, larvae damage turfgrasses in the northeastern U.S. from April to October. Insecticides from several classes are extensively used to manage both species; however, inappropriate use has led to the development of insecticide resistance in both species and has negatively impacted nontarget predators of P. japonica, thus warranting research on alternative insect control options. We studied the effects of liquid and granular formulations of Metarhizium anisopliae (Metschnikoff) Sorokin strain F52 against P. japonica and L. maculicollis larvae under field conditions. The liquid formulation provided 31 - 46% control of L. maculicollis larvae, but did not control P. japonica larvae. The granular formulation provided 49% control of P. japonica larvae on aerated turf, but did not control these larvae in nonaerated turf nor did it control L. maculicollis larvae. Whereas the overall effectiveness of M. anisopliae F52 for controlling turfgrass–infesting larvae of P. japonica and L. maculicollis ranged from none to moderate, it may be useful in areas where insecticide use is restricted.