Qld farm gets third Panama result

A devastating fungal disease has been found at a Queensland banana farm for the third time this year.

The Department of Agriculture on Thursday confirmed one plant had tested positive for the soil-borne Panama TR-4 at the Robsons' Tully banana farm.

Experts will now determine how many crops will need to be destroyed at the property, which was already operating under strict biosecurity measures.

The affected area has been closed off but the department says the disease could still spread.

About 16,000 plants were destroyed and the farm closed for eight weeks after the disease was first detected in March.

An extra hectare was also earmarked for clearing after a second positive test in August.

Panama disease, which can survive in earth for up to 40 years, wiped out the Northern Territory's banana industry in the 1990s.

It cannot be cured or controlled by any known chemical, however it does not pose any human health risks.

Another positive result at a farm near Mareeba in April was later proved false.