author(s)
Mangla Ram Bajiya and Dharam Pal Abrol

abstract
The present studies on effect of insecticides on foraging behaviour of honey bees (Apis mellifera L.) on mustard (Brassica napus) were conducted. Five insecticides methyl-demeton >acetamiprid >imidacloprid >diamethoate >thiamethoxam were sprayed on the mustard field during blooming and checked the pollinator visiting rates and compared with no-treatment control. Honeybee visitation rate was lower in insecticide treated plots with different degree. The repellent effect of Apis mellifera L. was observed after 24 hrs of spraying followed by methyl-demeton (79.4, 85.6, 86.6, 85.6 per cent), acetamiprid (75.5, 79.5, 80.6, 81.0 per cent), imidacloprid (73.7, 79.6, 75.0, 71.4 per cent), diamethoate (70.3, 73.4, 76.3, 77.1 per cent) and thiamethoxam (66.1, 70.7, 67.0, 64.5 per cent) during 2014-15 and 2015-16 respectively. However, the repellent effect of honey bees was not observed in treatment of control. The order of repellency due to different insecticides was methyl-demeton provide average values of (79.4, 85.6, 86.6, 85.6 per cent) >acetamiprid (75.5, 79.5, 80.6, 81.0 per cent) >imidacloprid (73.7, 79.6, 75.0, 71.4 per cent) >diamethoate (70.3, 73.4, 76.3, 77.1 per cent) >thiamethoxam (66.1, 70.7, 67.0, 64.5 per cent). Only after 7 days after treatment, honeybee visitation rates were recovered relative to the control. It is thus evident that methyl-demeton followed by acetamiprid, imidacloprid, and diamethoate were more repellent effect of the honey bee forager and thiamethoxam having insecticidal properties was found to be less repellency of honey bee forager.