Abstract: In this paper, the activities of acetylcholinesterase (AChE) and esterase in kidney bean seedlings and their sensitivity to pesticides were analyzed. Results indicated that the activities of AChE and esterase were varied during different germination and growth periods of kidney bean seedlings. The specific activity of AChE was the highest after 6 days of germination, which was up to 0.969 U/mL, and the esterase activity reached up to 1.9433 U/mL after 2 days of germination. The AChE from 6-day-old kidney bean seedlings was more sensitive to pesticides than the esterase from 2-day-old kidney bean seedlings, and the detection limits for dichlorvos, oxidized dimethoate and methomyl were 0.025, 0.07 mg/kg and 0.07 mg/kg, respectively, which were all below the maximum allowable residue limits. Therefore, AChE derived from kidney bean seedlings can meet the requirements for rapid detection of organophosphorus and carbamate pesticide residues.

Key words: acetylcholinesterase, esterase, kidney bean, organophosphorus pesticides, carbamate pesticides