Interception and hot water treatment of mites and nematodes on root crops from the Pacific Islands

Root crops are major food crops and export commodities in the South Pacific. However, the presence of mites and nematodes results in rejection or treatment of these crops exported to New Zealand. Current disinfestation methods relying on fumigation result in shorter produce shelf life. This paper summarises the organisms intercepted on root crops from the Pacific Islands and sent for identification in New Zealand, with particular reference to mites and nematodes. Results of a laboratory experiment examining the response of representative mite and nematode species to hot water treatment indicated times of less than 4 min at 48°C or 2 min at 49°C resulted in 99% mortality. The implications of these heat treatments for root crops are discussed. Additionally rearing methods are presented for two mite species: a mould mite and a bulb mite. These species will be relevant for use in future New Zealand and Pacific Island disinfestation studies.