Egg distributions of insect parasitoids: modelling and analysis of temporal data with host density dependence.

A simple numerical procedure is presented for the problem of estimating the parameters of models for the distribution of eggs oviposited in a host. The modelling is extended to incorporate both host density and time dependence to produce a remarkably parsimonious structure with only seven parameters to describe a data set of over 3,000 observations. This is further refined using a mixed model to accommodate several large outliers.

The relationship between dietary specialism and availability of food and water on cannibalistic interactions among predatory mites in protected crops.

The interplay between dietary specialism, the tolerance of food and water stress and level of cannibalism is likely to be important in determining the outcome of biological control using inundative releases of multiple natural enemies, such as phytoseiid mites in protected crops. The dietary specialist, Phytoseiulus persimilis, with a short immature development time (4-5 days) when plentiful food was available had a low ability to survive without food (5 days), even with access to water. The dietary generalists, Neoseiulus californicus, N.

Phytoseiid mites in protected crops: the effect of humidity and food availability on egg hatch and adult life span of Iphiseius degenerans, Neoseiulus cucumeris, N. californicus and Phytoseiulus persimilis (Acari: Phytoseiidae).

The effect of relative humidity on egg hatch success for Iphiseius degenerans, Neoseiulus californicus and N. cucumeris was described by a binomial model with a parallel slope. The shape of the response differed for Phytoseiulus persimilis and a model with separate parameters gave a significantly better fit.