抄録
A comparison of the seasonal changes in the numbers of foxglove aphid alates, Aulacorthum solani, caught in yellow water pan traps between a potato field (no control) and a weedy field (hibernaculum) was conducted from 1986 to 1989 in the Tokachi district of Hokkaido. A low number of A. solani alates were trapped in June that had migrated from the hibernaculum. A high number of alates that appeared on host plants around traps trapped from mid-July. The time of first trap catch differed each year, but the peaks of trap catch coincided.