The fight to save Cavendish bananas as farms fall to Panama disease

Growers, researchers and plant breeders are looking for a genetically modified saviour for the world's most popular banana variety after the 11th detection of a soil-borne fungus in Queensland.

The fight to save Cavendish bananas as farms fall to Panama disease

Leon Collins's banana farm south of Cairns is the newest front in the war against a soil-borne fungus threatening global production of Cavendish bananas.

"Some days you think you're fighting a losing battle. It is really hard," the Tully farmer said.

"It's heartbreaking, but it's just what we've got to live through."

For more than a decade, growers along the Tully River have been living with Panama disease tropical race 4 (TR4), which, despite their best efforts, has been slowly spreading down the waterway.

The fungus cannot be eradicated.

Its spores live in the soil for decades, waiting to attack banana plants through their roots and eventually kill them.

It poses a particular risk to the Cavendish variety of banana, which accounts for more than 97 per cent of fruit produced in Australia, and much of the world.

Headshot of Tully banana farmer Leon Collins in front of a yellow brick wall.

The latest incursion of TR4 was detected on one of Leon Collins's farms. (ABC Rural: Sophie Johnson)

As the chair of the Australian Banana Growers' Council, Mr Collins had been leading the fight against TR4, but the latest, and 11th, local detection means he is now also in the trenches. 

"It's a fact of life and sometimes you get dealt the wrong cards," he said. 

But he hoped the rest of the industry would be spared the same battle.

"I believe our saviour is going to be plant breeding,"

Mr Collins said.

Researchers, scientists and plant breeders have been edging ever closer to a new weapon, one growers can deploy ahead of an incursion: a Cavendish banana variety that can withstand the disease.

New frontline, new frontiers

In 2024, researchers at the Queensland University of Technology received federal government approval to commercialise the world's first genetically modified banana, developed specifically to resist TR4.

Named QCAV-4, it looks and tastes the same as a Cavendish, the only difference being the added resistant gene.

The fruit was trialled in the Northern Territory, where Panama disease has been established since the 1990s, but currently no-one is growing it commercially.

But Anthony James from QUT's Centre for Agriculture and the Bioeconomy said growers were showing interest.

"Growers in the Tully Valley would love to see our bananas trialled more extensively so they can understand whether they're comparable to current varieties,"

he said.

"We have a commercialisation department that will work with the industry, growers and retailers in the future to progress the commercialisation."

While the bananas are not currently available to Australian consumers, historically shoppers have been sceptical about genetically modified foods

The Office of Gene Technology Regulator's most recent report on community attitudes (2024) found only 32 per cent of respondents were willing to eat GM fruit and vegetables. 

But Dr James said QCAV-4 had undergone rigorous scientific and regulatory assessment, and that when the banana became available to consumers, they could be confident it was safe to eat.

Three small banana plants in pots.

Queensland University of Technology developed a GM banana resistant to TR4. (Supplied: Queensland University of Technology)

Other projects, like the one led by Naomi Abbott from North Queensland Banana Research, are using more established methods, like crossbreeding. 

"We've commenced plant breeders' rights on a few of our key lines … so we're expecting to have our first Cavendish line available by 2028,"

she said.

"But there's still many other varieties in the pipeline and hopefully some of those will also make it the whole way through our testing process and reach commercialisation."

She said the TR4-resistant breeds were developed in collaboration with FIA, a Honduran banana breeding program.

"In our pipeline now, we've probably got 30 to 40 hybrids that we're working with … we've four that we're dealing with a bit more seriously," she said.

"In terms of Cavendish, there's two we're working with and one clear frontrunner."

More than 16,000 banana plants have been killed by biosecurity officers on a Tully farm.

Outward symptoms of panama disease start with the banana plant's leaves beginning to wilt and go yellow. (ABC Rural: Charlie McKillop)

Queensland's Department of Primary Industries was also working towards introducing TR4-resistant Cavendish varieties, with help from overseas.

Principal Horticulturalist Jeff Daniels said seven Cavendish lines had shown sufficient resistance, but they did not also produce enough fruit to be suitable for the Australian industry.

"They all have a yield penalty ranging from 60 to 90 per cent of the industry standard," he said. 

"We're not there yet and … additional investment is required to develop a better TR4-resistant Cavendish than we currently have available."

Living with Panama disease

So far, the strict biosecurity measures implemented by Tully region growers appear to have contained TR4 to that district. 

"It's a whole approach that we're using all together and it's very hard to slow this thing down," Mr Collins said.

"Innisfail [50km south] is our largest growing area now so we have to protect that and make sure we keep it free of disease."

Bananas being washed in a packing shed.

Banana farmers in the Tully region have employed strict biosecurity measures to slow the spread of TR4. (ABC Rural: Sophie Johnson)

Nearby Tully banana farmer Adrian Crema did not have TR4 on his farm, but said the threat was never far from his mind.

He was encouraged by the progress towards resistant varieties.

"I was really, really happy to hear that the research is getting done and there's possibly some varieties coming on the horizon," he said. 

"To me, that was the most exciting thing I'd heard all year."