Dissemination of Beauveria bassiana by Honey Bees (Hymenoptera: Apidae) for Control of Tarnished Plant Bug (Hemiptera: Miridae) on Canola

Large screened cages trials were conducted to assess the potential of honey bees, Apis mellifera L., to vector Beauveria bassiana (Balsamo) to canola, Brassica napus L., against the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois). The bees effectively vectored the inoculum from the hives to the crop. Conidia of B. bassiana was recovered from 100, 64-77, 70-82, and 47-83% of bees, flowers, leaves, and L. lineolaris samples, respectively, collected on four sampling dates in 2002 and 2003. Mean mortalities of L. lineolaris collected from the Beauveria-treated cages in the field were 56 and 48% compared with 9 and 10% in the controls on the first and second sampling dates in 2002, respectively, and 22 and 45% in the treated cages in the field compared with 15 and 22% in the controls on the first and second sampling dates, respectively, in 2003. These results indicate that bees may provide a new novel means for applying B. bassiana to manage L. lineolaris on canola. The benefits are better pollination, reduction in pest pressure of L. lineolaris, and reduced reliance on insecticides.