Plant Growth and Population Dynamics

This chapter covers the following: predictors of yield reduction (symptoms of nematode infestation, pre-plant nematode density, and nematode multiplication) due to nematode infestation; mathematical models for the prediction of crop reduction based on the relationship between nematode density at planting and average weight of single plants at harvest (demonstrated for Ditylenchus dipsaci on onion and root-invading nematodes, such as Pratylenchus spp.); mechanisms of growth reduction in perennial plants due to nematode infestation; tolerance limit (T) and minimum yield (m) as measures of crop tolerance, and the effects of nematicides (nematistatics and contact nematicides) on these parameters; and a mathematical model for the prediction of the population densities of nematodes with one generation or several generations per season.