Aggregative Distribution Pattern of the Japanese Beetle, Popillia japonica Newman (Coleoptera: Scarabaeidae), and the Role of Former Occupants in the Formation of an Aggregation

Abstract

The spatial distribution pattern of the Japanese beetle, Popillia japonica Newman was analyzed by the m-m method and it was shown that the beetles were aggregative on a vine. The ratios of males to females on vines and shoots were 1.794 and 1.732, respectively. Experimental analyses showed that either sex tethered on a leaf attracted males, resulting in their accumulation. The attraction was also observed with ether extracts of the body surface of both sexes. This suggests that an airborne substance from the former occupants is responsible for the participation of males in the formation of an aggregation. However, the cause of female participation could not be determined. © 1983, JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY. All rights reserved.