Aphid (Homoptera: Aphididae) accumulation and distribution near fences designed for cabbage fly (Diptera: Anthomyiidae) exclusion


  • M. K. Bomford Division of Plant and Soil Sciences West Virginia University P.O. Box 6108 Morgantown, WV 26506-6108
  • R. S. Vernon Pacific Agri-Food Research Centre P.O. Box 1000 Agassiz, BC V0M 1A0
  • Peeter Pats Nordic Academy for Advanced Study Nedre Vollgates Oslo, Norway N-0158


Aphids accumulate near exclusion fences designed to intercept Delia radicum (L.) movement into fields. Aphid accumulations increase with increasing fence height, but are not affected by fence overhang length. Overall aphid levels are higher in small (4.3 m square) enclosed plots than in unenclosed plots. Enclosing large (38 m square) plots does not alter overall aphid catches, but does alter aphid distribution within enclosures. In large enclosures aphid accumulations are higher at enclosure perimeters than interiors, with the highest accumulations near enclosure corners. This concentric distribution is not observed in unfenced areas, and is not altered by the addition of a trap crop outside an enclosure.

Key words: Myzus persicae; Delia radicum; physical control