Abundance of <i>Lygus</i> spp. (Heteroptera:Miridae) in canola adjacent to forage and seed alfalfa


  • H. A. Cárcamo Agriculture And Agri-Food Canada Lethbridge Research Centre PO Box 3000 Lethbridge, AB T1J 4B1
  • J. Otani Agriculture And Agri-Food Canada Beaverlodge Research Farm Box 29 Beaverlodge, AB T0H 9C0
  • J. Gavloski Manitoba Agriculture and Food 65 - 3rd Ave. NE Carman, MB R0G 0J0
  • M. Dolinski Alberta Agriculture, Food and Rural Development 7000 B 113 Street Edmonton, AB T6H 5T6
  • J. Soroka Agriculture and Agri-Food Canada Saskatoon Research Centre 107 Science Place Saskatoon, SK S7N 0X2


Lygus bugs, canola, alfalfa, forage harvest


Our objectives were to document the abundance of lygus bugs (Miridae) in canola after the cutting of adjacent alfalfa hay fields and to document their seasonal activity in canola plots grown in close proximity to alfalfa seed. Cutting alfalfa did not increase abundance of lygus bugs in nearby canola in sites near Barrhead, Alberta (1998-1999), in the Peace River area of British Columbia (2000) or near Carman, Manitoba (2001). In Saskatoon, from 1993-1995, lygus bug numbers remained at low levels in seed alfalfa and canola and there was no indication that the pest species (L. lineolaris) in canola moved in significant numbers from the adjacent alfalfa seed field. We conclude that alfalfa forage harvesting generally does not result in massive movement of lygus bugs to nearby canola.


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