Construction and preliminary evaluation of a simulation model of the population dynamics of the potato cystnematode Globodera pallida

Abstract

A model is constructed to simulate the popuiation dynamics of the potato cyst-nematode, Globodera pal/ida, and its effect on the growth of the potato. Parameters and rate variables are estimated from published data, and a preliminary evaluation is performed. Despite its simplicity, the model can provide realistic predictions of the real system's behaviour: the predicted relation between initial nematode density and the annual multiplication rate, and the effect of nematode density on tuber yield, are simulated well; the effects of early harvesting are similar to those described in the literature; and the predicted seasonal changes in population structure are in reasonable agreement with field observations. The \Veaknesses and potentials of the model, and of the dynamic simulation approach, are discussed.

Effect of crop rotation on Globodera rostochiensis and on potato yield1

“…The above results indicated that, on susceptible potato, the increase of a PCN field population is on average similar to that of other growing areas (Trudgill et al, 1987) and the annual multiplication rate with all initial densities is as described in Ward et al (1985). The average population density in the monoculture plots was a little less than the average (85 larvae g -' ) in the experiment reported by Jones & Parrott (1969).…”

A field study of the relationship between pre‐planting density of Globodera pallida and the growth and yield of two potato cultivars of differing tolerance

“…These range from a straight line relation between yield and initial nematode population density (Brown, 1969), deterministic equations developed by Seinhorst (1965) and Elston, Phillips & Trudgill(1990), in which nematode population density is expressed on a log. scale, to the interactive model described by Ward, Rabbinge & den Ouden (1985). None of these models can be used t o predict satisfactorily yield losses without additional 0 1990 Association of Applied Biologists information on various environmental factors including soil type, the likely yield potential of the site and of the cultivar (Trudgill, 1986a).…”

“…Effective modelling of crop growth and yield losses due to PCN is also required to develop predictive models of PCN population dynamics (Ward et al, 1985). Several models have been described which are based on the observation that, in one season, the multiplication rate of PCN decreases with increasing initial population density.…”

“…Jones & Perry (1978) assumed that all cultivars were equally damaged whereas Seinhorst (1967) allowed for differences between cultivars in their tolerance of damage. Both models are essentially descriptive because, unlike that of Ward et al (1985), neither directly allows for differences in growth potential between sites or cultivars.…”