A Modelling Approach

Growers of floricultural crops are still dependent on chemical insecticides because of low consumer tolerance to damaged produce. More knowledge of natural interactions between insects and their host plants would allow insect pests to be controlled in a more environmentally friendly and effective way. This thesis analysed the system of biological interaction between the pest Frankliniella occidentalis (Western Flower Thrips) and its host plant Chrysanthemum x morifolium. Mathematical prediction models were developed to describe the growth and development processes of the plant and the insect population, on the assumption that there is a temperature-dependent interaction between flower growth and development and thrips population growth. An introductory study developed a method for linking flower growth and development that was used in subsequent studies. The second study aimed to predict growth responses of non-infested chrysanthemum flowers to temperature and irradiation, in order to distinguish between temperature and thrips effects on chrysanthemum flower size. Since F. occidentalis feeds on both flowers and leaves, a model constructed in the third study served as