Development and Survival of Japanese Beetle Larvae on Carrot and Other Foods

Abstract

Third-stage larvae of the Japanese beetle, Popillia juponica Newman (Coleoptera: Scarabaeidae), were collected in the field at Rutherfordton, N. C, held in storage at 7°C for about 20 days, and then exposed to raw carrot, grass sprouts, skim milk, wheat germ, soybean protein, or brewer's yeast in a soil medium of Michigan peat and sassafras sandy loam soil (2:1 by volume) at 30°C. After 30 days, the weight gains of larvae fed a 1% concentration of skim milk (in grams per 100 grams of soil), 1% wheat germ, or 13% carrot were not significantly different from the standard (2% grass seed). Concentrations of soybean protein, skim milk, or wheat germ of less than 0.1% and brewer‗s yeast at concentrations of 0.01–1.0% did not increase the weight of the larvae beyond the increase of larvae held without food. Adult emergence from larvae fed grass sprouts, carrot, or 1% wheat germ were 15, 12, and 3%, respectively. No larvae exposed to the other foods emerged as adults.