Department of Zoology, Environmental Research Laboratory, S.S.V. (P.G.) College, Hapur - 245 101, U.P., India
All the pesticides reduced the acetylcholinesterase activity in worker bee. Organophosphates showed maximum inhibitory effect on the activity of acetylcholinesterase followed by organochlorines. But neem oil showed insignificant inhibitory effect. Methyl parathion and dimethoate were highly toxic and showed maximum inhibitory action followed by heptachlor, malathion and endosulfan. There was significant reduction in the activity of acetylcholinesterase in respect to concentration level-2 (½ of LC50 at 96 hr.) but concentration level-1 (¼ of LC50 at 96 hr.) did not have so well defined inhibitory effect, except methyl parathion and dimethoate. Maximum inhibition in the activity of the enzyme was in 15 days old bees followed by 25 days old and 5 days old worker bees. Neem oil was found to be nontoxic and was supposed to be bee friendly pesticide. The toxic effect of different pesticides on the activity of enzyme acetylcholinesterase was found as Methyl parathion > Dimethoate > Malathion > Endosulfan > Neem oil.
