Emamectin benzoate as a candidate for a trunk-injection agent against the pine wood nematode, Bursaphelenchus xylophilus†

In order to develop an effective trunk-injection agent against pine wood nematode, Bursaphelenchus xylophilus, an in vitro assay was used to examine the antinematodal activity of 58 commercially available compounds with known modes of action. Among compounds tested, the GABA receptor agonists had better anti-nematodal activity than compounds influencing glutamate, N-methyl-D-aspartate, β-adrenergic, dopamine, muscarinic acetylcholine and nicotinic acetylcholine receptors, as well as those inhibiting acetylcholinesterase, monoamine oxidase, 5-hydroxytryptamine uptake and Ca2+, K+, Na+ and Cl− channels. Avermectins and milbemycins strongly inhibited propagation of the nematode. Emamectin benzoate proved to be the most active (IC95 0.050 µM) being over 140 times more active than the active ingredient of conventional trunk-injection agents. It is concluded that emamectin benzoate is a strong candidate for an anti-nematodal trunk injection agent. © 2000 Society of Chemical Industry