DOSE TRANSFER OF BACILLUS-THURINGIENSIS FROM CABBAGE TO THE DIAMONDBACK MOTH - A GRAPHICAL SIMULATOR

The application of agrichemicals is a highly inefficient process and o ne of the main causes of the environmental and health risks currently associated with pesticide usage. Efforts to mitigate this inefficiency have largely been unsuccessful, due principally to the poor understan ding of the processes involved in the spray application of pesticides, from atomization to biological effect. A generalized model of the app lication system for pesticides from atomization to biological result i s described in this overview. The model allows the investigation of th e biological consequences of altering the application parameters for t he bacterial insecticide Bacillus thuringiensis when used against the diamondback moth (Plutella xylostella L.) with cabbage as the substrat e. Parameters input into the model include the in-flight droplet size frequency distribution of the spray cloud, spatial distribution of the deposit, spread and subsequent environmental degradation of the depos it, and behavioral and toxicological effects. It is hoped that such a modelling approach can afford insights into the application process, a nd, through a better understanding of the inefficient but still highly effective hydraulic application systems used worldwide, reduce that i nefficiency to tolerable levels.