MONITORING ANNUAL FLIGHT PATTERNS OF THE POTATO APHID MACROSIPHUM EUPHORBIAE (HOMOPTERA: APHIDIDAE), IN SOUTHERN ONTARIO

Abstract

AbstractPopulations of flying potato aphids (Macrosiphum euphorbiae (Thomas)), available to initiate new infestations on crops, were measured by plant trapping from 1966 to 1971 and by suction trapping from 1967 to 1978 at Harrow, Ontario. Yearly total catches were extremely variable and in some years there were periods of 2 weeks without catches during the summer. The long term annual flight pattern was a unimodal curve with a peak in August. Counts by plant trapping correlated with those obtained by suction trapping, and catches on Brussels sprouts, tomatoes, and peppers were all positively correlated. Plants exposed on a background of bare soil attracted more alatae than those exposed on a background of mowed weeds. The first female alatae were caught in the suction traps on 21 June ± 5 days each year and the first male alatae on 22 October ± 2 days. The last female alatae were caught on 21 October ± 5 days and the last males on 6 November ± 2 days.