Disinfestation of floriculture products with ethyl formate fumigant: Vapormate^®

Rejection of cut flowers in export markets as a result of phytosanitory failure is a major problem for Australian growers and exporters of floriculture products. Biosecurity requirements of importing countries vary, however, most countries require a phytosanitary certificate and an inspection at port of entry to ensure product is free of pests and diseases. Chemical fumigation and insecticidal dipping are commonly used as end point treatments by the floriculture industry for disinfestation prior to export. Cut flowers and foliage vary in their response and tolerance of disinfestation treatments depending on the flower type and chemicals used. Current disinfestation treatments are not fully effective against the range of pests present in cut flowers, so alternative methods need to be investigated. This study assessed fumigant ethyl formate (Vapormate^®) as a suitable method of disinfestation for Australian wildflowers. The aim was to reduce insect loads to undetectable levels with minimal damage to the flowers, while reducing chemical inputs and minimizing environmental impacts compared to current disinfestation methods. Sixteen Australian wildflower species (including 21 varieties) were treated with varying doses of ethyl formate: i) 90 g m^-3 2 h; ii) 90 g m^-3 1 h; iii) 60 g m^-3 2 h; iv) 60 g m^-3 1 h; and v) 30 g m^-3 1 h. Unacceptable phytotoxic effects were evident for the higher dose and treatment time (90 g m^-3 2 h) for 6 of the 10 wildflower products tested during vase life trials. Phytotoxic affects were reduced to undetectable levels at the lowest doses and reduced treatment time (60 and 30 g m^-3 1 h), however, insect mortality rates were unacceptable.