Role of Movement in Evaluation of Area-Wide Insect Pest Management Tactics

Abstract

Insect management tactics can be divided into three groups according to the influence of insect movement on their evaluation: (1) the use of insecticides and antibiotic host plant characters directed against immatures, (2) the use of trap crop, trap out, adulticides, and antixenotic host plant characters directed against mobile adults and augmentative biological control relying on mobile control agents, and (3) wild host management and the use of autocidal genetic controls applied on an area-wide basis. A simulation model of insect movement is subjected to a sensitivity analysis based on average parameter values derived from the literature. It is used to explore the process of reinvasion of an area in which a pest population has been suppressed. It is estimated that suppression of Heliothis virescens (F.) over an area 25 km in diameter would be necessary to prevent substantial infiltration into the treated area by the wild population within two generations. Given such potentially large treatment areas, eight experimental designs that reduce the size and number of areas required to test the efficacy of area-wide control tactics experimentally are explored. The best designs require two smaller areas for 6 yr or two larger areas for 2 yr. The latter requires extensive sampling effort because it depends on measuring spatial gradients of insect density