AN INSECT HOST–PARASITE POPULATION

Abstract

Eight populations of Trialeurodes vaporariorum and Encarsia formosa were propagated on tomato plants in the greenhouse for about eight months. Although there was some variation in the growth-forms of host and parasite among the experiments, the general trend in each experiment was one of fluctuations of slightly, but distinctly, increasing amplitude. As extraneous sources of variation had only a slight influence on the growth-forms, the fluctuations resulted from host–parasite interaction. The T. vaporariorum – E. formosa system, is well suited for an investigation of the principles of host–parasite interaction.