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Optimal parasitization in a size-structured host-parasitoid model. (English) Zbl 0894.92028
Summary: A continuous size-structured model for a host-parasitoid interaction is derived and analyzed. Parasites attack only immature hosts according to a size-specific preference (probability) distribution $$\psi$$. We investigate the problem of how to determine $$\psi$$ so as to minimize the equilibrium level of the adult host (pest) population. It is shown that this problem is equivalent to that of maximizing the expected number of parasitoid emergences (per immature host) of an adult parasitoid over the course of its life time. Under certain further conditions it is shown that this maximization is obtained by (and only by) parasitization that is concentrated on certain specified immature size classes.

##### MSC:
 92D30 Epidemiology 93C95 Application models in control theory 45K05 Integro-partial differential equations