SCREENING OF PHYTOPHAGOUS INSECTS FOR BIOLOGICAL CONTROL OF WEEDS

Abstract

AbstractIt is necessary to demonstrate the host specificity of an exotic phytophagous insect before introducing it for the biological control of a weed. The widely-used "starvation test" made on economic plants is considered inadequate for this purpose and we propose that studies should be broadened to include the following: (1) study of the insect’s biology, including host–plant records, with particular attention to adaptations likely to restrict the host range, (2) review of the plants attacked by related insects, (3) determination of the laboratory host range of the insect, (4) investigation of the chemical or physical basis of host–plant recognition, (5) starvation tests on economic plants to confirm the limits of the previously established host range, (6) establishment of the insects’ potential effectiveness for weed control. A limited amount of feeding on economic plants in the laboratory is not reason for rejection, if other criteria show the insect has a high degree of specificity.