Recent studies on the potential for biological control of bracken using fungi

Abstract

SynopsisCurl-tip disease of bracken (Pteridium aquilinum) is recorded from many sites in Great Britain. Evidence is presented which corroborates the findings of earlier workers that more than one organism is associated with the disease. Three fungi (Phoma aquilina, Ascochyta pteridis and Septoria sp.) are commonly isolated, even from the first visible necroses, suggesting that synergism may operate in pathogenesis. However, Phoma aquilina Sacc. and Penz. is more pathogenic than the others when used independently in inoculations via wounds into bracken raised in growth cabinets or the greenhouse. Field trials of a formulation of spores of P. aquilina, suspended in a dilute solution of the herbicide ioxynil with broth and glycerol, are reported. The potential of such a mycoherbicide for bracken control is considered.