Naturally derived insecticides: Prospects for forestry use

Abstract

Much interest exists in using natural chemicals as insecticides. Plants manufacture a vast array of chemicals that help protect them against insect attack. These could serve as sources or models for future insecticides with novel modes of action that are highly effective and safe. Three compounds that are currently receiving much attention are examined for their potential for forestry use in Canada. These compounds are alpha-terthienyl from members of the flowering plant Family, Asteraceae; MK-244, a semi-synthetic analogue of abamectin, which is a natural avermectin compound from the soil microorganism, Streptomyces avermitilis, and neem seed extract and its principal active ingredient, azadirachtin, from the neem tree. Their potential is assessed against seven criteria that must be met for successful development: effectiveness against major forest pests; safety for non-target organisms; degradability in the forest environment; availability in large quantities; economical cost; development by the chemical industry; and acceptability to the public. All three compounds are in early phases of development and although each shows promise by meeting certain criteria, not enough information is available yet to determine their overall suitability. Nevertheless, these examples demonstrate the great potential for finding future insecticides from natural chemicals or their derivatives.