Fusarium oxysporum and Fusarium avenaceum associated with yield-decline of pyrethrum in Australia

Abstract

Fusarium species were isolated from roots, crowns, basal petioles but rarely from the leaves of infected pyrethrum (Tanacetum cinerariifolium) plants showing poor growth and stunting in yield-decline sites of northern Tasmania and the Ballarat region of Victoria, Australia. Multigene phylogenetic analyses using the internal transcribed spacer (ITS), the polymerase II second largest subunit (RPB2) and the partial translation elongation factor 1-α (EF1) sequences, identified F. oxysporum and F. avenaceum as the most frequently isolated species associated with root and crown diseases of pyrethrum, and F. equiseti and F. venenatum at a low incidence. Pathogenicity trials confirmed that F. oxyspo..