Incidence of Natural Ectomycorrhizal Infection of Pine and Eucalypt Seedlings in Three KwaZulu-Natal Nurseries

SYNOPSIS A survey of the incidence of natural ectomycorrhizal infection on selected species of pines and eucalypts was conducted in three commercial timber nurseries near Pietermaritzburg in 1990. A follow-up survey was conducted on one of the nurseries in 1995. The main objective was to determine whether the incidence differed significantly between nurseries and tree species, and whether any differences could be explained. The eucalypt seedlings had a low incidence of ectomycorrhizal infection, while the ectomycorrhizal status of pine seedlings increased with age, sometimes to high levels, but varied with tree species and nursery. The results for the pine seedlings were modelled by fitting logistic regression models. The significance and implications of the survey results are discussed.