A simple model of host‐parasitoid interaction with host‐feeding

Abstract

SummaryA simple mathematical model of host‐parasitoid interaction with host‐feeding was presented with special reference to the system of the greenhouse whitefly and the parasitoid Encarsia formosa. In the model, when a parasitoid encounters a host, it has a choice between feeding the host and ovipositing one egg in the host. It was shown that an intermediate value of the feeding ratio of all attacks gives the minimum equilibrium host density and the minimum amplitudes of fluctuation in the densities of the two species. Computer simulations of a modified model with time lags also gave the similar results. The model suggested for natural enemy introduction program that parasitoid species with host‐feeding habits are promising agents for effective controls for pest insects and that the timing of introduction is very important. By an evolutionary analysis, it was shown that the feeding ratio evolves to minimize the host density under natural selection among parasitoids.

Comparison of thermal tolerance of seven native species of parasitoids (Hymenoptera: Eulophidae) as biological control agents against Liriomyza trifolii (Diptera: Agromyzidae) in Japan

“…All of the eulophid parasitoids examined here kill hosts not only by parasitization, but also by host-feeding. Host killing by host-feeding is promising for the effective control of pest insects (Yamamura and Yano, 1988;Kidd and Jervis, 1989). Hence, an evaluation of efficient parasitoids should be based not only upon parasitization, but also upon hostfeeding (van Lenteren, 1986).…”

Dynamical consequences of optimal host feeding on host-parasitoid population dynamics

“…In Yamamura and Yano (1988) effects of host-feeding on population dynamics were studied in the framework of the Lotka-Volterra model with intraspecific competition in host population. They showed that for a positive intraspecific competition trajectories of the model converge to equilibrium while for zero intraspecific competition ecological equilibrium is neutrally stable.…”

“…Traditionally, host-parasitoid interactions were modeled by the discrete-time NicholsonBailey model, but continuous-time models based on the Lotka-Volterra like dynamics were also used (Briggs et al 1995, Yamamura and Yano 1988, Murdoch et al 1992, Murdoch and StewartOaten 1989. Inclusion of optimal host-feeding behavior of parasitoids lead in this article to nonsmooth differential equations and differential inclusions.…”

“…It is believed that behavioral decisions of parasitoids may have a strong impact on host-parasitoid population dynamics. The effects of various behavioral decisions of parasitoids on host-parasitoid population dynamics were recently studied: searching for food versus ovipositing , searching for healthy hosts versus superparasitizing ), ovipositing versus host-feeding (Jervis and Kidd 1986, Yamamura and Yano 1988, Kidd and Jervis 1991a, Kidd and Jervis 1991b, Murdoch et al 1992, Briggs et al 1995, Jervis and Kidd 1995. Since host-feeding (i. e., the consumption of host haemolymph by the adult female parasitoid) may have a major impact on host mortality, host-feeding parasitoid species may prove to be good biological control agents (Kidd and Jervis 1989).…”

“…Moreover, the input of nutrients from a non-host source has a stabilizing effect while the use of host material for maintenance is destabilizing. In Yamamura and Yano (1988) the Lotka-Volterra continuous type model with time delay was considered. In this model host-feeding increased the speed of convergence of trajectories to an equilibrium.…”