Genetic structure of populations of Fusarium proliferatum in soils associated with Livistona mariae palms in Little Palm Creek, Northern Territory, Australia

Abstract

Fusarium proliferatum (Matsushima) Nirenberg (teleomorph = Gibberella intermedia) is a member of a group of closely related and agriculturally important fungal plant pathogens known as the 'Gibberella fujikuroi species complex'. The genetic structure of populations of F. proliferatum in non-agricultural soils collected from Finke Gorge National Park, Northern Territory, Australia, was investigated. F. proliferatum was isolated from soils from the root zone of Livistona mariae palms. Amplified fragment length polymorphism (AFLP) analysis of 77 isolates distinguished 73 unique haplotypes with an overall genetic similarity of 0.94. Cluster and bootstrap analysis indicated the population was composed of two well supported groups, possibly of clonal origin. Statistical analysis of the distribution of genotypes in the study area showed there were clear spatial subdivisions of genotypic diversity (P < 0.001) indicating limited mixing of genotypes.