MODELS FOR MATING DISRUPTION BY MEANS OF PHEROMONE FOR INSECT PEST-CONTROL

Models are presented to investigate the population dynamic behavior of a pest population with the release of pheromone for mating disruption . Three mechanisms of mating disruption are considered: (i) confusion of males, (ii) competition with female pheromone trails yielding false trail following, (iii) emigration of males prior to mating. In additi on, several refinements to confusion are considered. Confusion and emi gration of males were found to be very similar both quantitatively and dynamically; also, a combination of both mechanisms was very little m ore efficient than either one separately. False trail following is dif ficult to compare with the other two, since competition with wild fema les is involved and thus the total population size enters the equation s. Density dependence of the action of pheromones results in some case s in which mating disruption cannot control the pest population. Simil arly, aggregation of the pest population decreases the efficiency of t he method unless the pheromone action is density independent. Delayed mating of females makes control easier, and may constitute one mechani sm for mating disruption.