Investigations into the use of flame and the herbicide, paraquat, to control peppermint rust in north-east Victoria, Australia

Abstract

Autumn flaming, spring flaming, and combinations of both were compared with the use of the fungicide propiconazole for their effect on growth, disease levels and oil yields of peppermint growing at the Ovens Research Station near Myrtleford, north-east Victoria in 199415. Spring flaming severely disrupted plant growth, resulting in reduced oil yields despite low levels of disease. Autumn flaming promoted high oil yields, but cannot be recommended to growers due to current legal constraints in Victoria. The contact herbicide, paraquat, is used by peppermint growers in autumn as a clean-up measure; it substantially reduced viability of urediniospores of P. menthae and although not as effective as autumn flaming, its use may help to reduce the level of inoculum carried over into the winter from the previous crop.