Utilisation of phytochemicals against stored product insects.

Abstract

Plants modify insect behaviour by the production of attracting or repelling odours. Integrated stored product protection may utilise plant extracts and purified or synthesised compounds in the following ways: 1. Repelling odours for pest prevention in the vicinity of packed goods or around doors and openings in a storage, 2. Attractant odours for early pest detection, the monitoring of control techniques or mass trapping, 3. Toxic compounds for pest control. Recent research projects in these fields are described. Instead of testing plant extracts with a large number of active ingredients it may be advantageous to study the mode of action of one pure compound and its effect on stored product pests first. Data are given on a number of pure compounds tested for repellence and toxicity. Once removed from plants and the context of co-evolution, phytochemicals should be regarded as biodegradable chemicals and thus may be just as useful or harmful to man as other chemicals. Continuous application of doses sublethal to a part of a pest population is prone to elicit pest resistance sooner or later. Nevertheless, phytochemicals could play a major role in future integrated stored product protection.