No. TR4 does not affect other fruit crops; however, it infects most banana varieties including the main commercial variety, Cavendish.

Plants affected by TR4 rarely produce marketable bunches. Once established, the fungus persists in the soil for many years, making the production of susceptible banana varieties such as Cavendish economically unviable.

Panama disease enters via the roots. Fungal spores germinate and use their filaments (hyphae) to enter the roots through natural openings or wounds, spreading through the corm and into the stem.

Until the fungus blocks the vascular tissues carrying the water and nutrients, there might not be any signs that the plant is infected. It might take weeks or a few months for signs to show depending on the environmental conditions (such as wet, dry, or extremely hot), and the plant’s age.

As blockage of the vascular tissue develops the plant yellows, wilts and eventually dies.

The disease does not affect the fruit so bananas are still good to eat.

TR4 cannot be eradicated by any biological or chemical controls.

Early detection, rapid destruction of infected plants and on-farm restrictions are the only way to control and contain the disease.

Reporting symptomatic plants immediately to Biosecurity Queensland on 13 25 23 safeguards farm viability and protects the wider industry.

• Yellowing leaf edges in the early stages

• Brown or black leaf edges

• Yellowing across the whole leaf

• Wilted, collapsed and dying older leaves forming a “skirt” around the stem

• Young leaves possibly still green and upright while older leaves and the stem are affected

• Split stem base (but not always) through two or three layers initially – later, deeper and higher up.

If you see signs of TR4, contact Biosecurity Queensland on 13 25 23 immediately.

Early detection, rapid destruction of infected plants and on-farm restrictions are the only way to control and contain the disease.

If TR4 is left unchecked on a farm, the disease can spread rapidly through people and vehicle movement.

It is a legal requirement to report suspicious plants, within 24 hours, under the Biosecurity Act 2014 that classifies Panama TR4 as a Category 1 restricted matter.

No. Cutting stimulates the fungus promoting spore production and increases the risk of the disease spreading on and off the property. It can also make it harder to get samples for diagnostic testing.

If you have cut down a symptomatic plant, contact Biosecurity Queensland immediately on 13 25 23.

Good on-farm biosecurity measures are critical to not only protect farms from TR4 but to also contain the disease if it is detected on the farm.

Managing the movement of soil, water and plant material entering and exiting farms is the key to effective on-farm biosecurity. Some on-farm biosecurity measures can include:

• Zoning. It can provide simple and cost-effective biosecurity layers to manage disease risk pathways onto and off a farm.

• Footwear exchange stations and foot baths.

• Cleaning and disinfecting all vehicles and machinery.

• Setting up a clean access road.

More information see the Grower Kit.

Yes, there are different races of the Fusarium oxysporum f. sp. cubense fungus which cause Panama disease, but not all are present in all the banana growing areas of Australia. The different races affect different banana varieties.

Race 1 infects a range of varieties Lady Finger, Sugar and Ducasse, but not Cavendish.

Race 2 infects cooking bananas like Bluggoe and Blue Java.

Race 3 infects only Heliconia species not bananas.

Race 4 infects most varieties including Cavendish, Lady Finger and Ducasse.

There are two important strains of Race 4.

Tropical race 4 occurs in tropical growing regions, like Far North Queensland.

Subtropical race 4 occurs in subtropical regions and usually only produces signs in Cavendish after a period of cold stress. Subtropical race 4 has been under quarantine control in south east Queensland, northern New South Wales and Western Australia for some time.

TR4 does not affect the fruit, so bananas are safe to eat.

There is currently no way to test for TR4 in soil or water. Early identification of plants showing signs of the disease and subsequent sampling and laboratory testing of these plants are the only way to know if the disease is present.

Surveillance is conducted by experienced authorised ABGC surveillance officers under the ABGC Grower Support (Biosecurity) Program.

This involves a pre-arranged/booked day and time through the Grower Support (Biosecurity) surveillance coordinator.

Surveillance is critical for early detection and treatment of the disease.

Regular checking of plants by growers is critical for early detection and containment. Surveillance can be integrated into regular farming practices through training staff how to identify and report suspect plants.

Read about the signs and symptoms of Panama TR4.

ABGC Grower Support (Biosecurity) conducts a surveillance program and growers check their plants to look for signs of the disease. When a plant showing signs of TR4 is identified, authorised officers visit the property to assess the plant for TR4.

• A visual inspection. Plants are inspected for external signs of TR4 including leaf yellowing, wilting and stem splitting. If found, the grower is advised that suspect plants have been found. The plant is then cut to look for internal signs – a yellow, reddish or brown-black discolouration of the stem or corm’s vascular tissue. Photos are taken of intact and cut plants.

• Collect and send samples. Samples of plant material are taken from any discoloured tissue that is found in the stem or corm as the plant is systematically examined. The plant or the stump is then marked and a sign placed indicating that samples have been taken. Samples are securely packaged, labelled, and sent with a secure chain of custody to a specialised laboratory.

• Laboratory testing. A range of laboratory tests are undertaken which can take up to 6 weeks.

• Give the results. The results of the tests are given by phone and confirmed by a letter and a diagnostic report. If positive for Panama TR4 the grower will be advised how to control and contain the disease. Biosecurity Queensland also notifies key stakeholders of the positive result, without giving away identifying information on the grower or the property.

Read more about diagnosing Panama TR4 in the Grower Kit.

When test results are positive, a Biosecurity Queensland officer calls the grower directly and confirms via a formal letter and diagnostic report.

For commercial banana farms where TR4 has been detected, growers are required to follow the mandatory requirements of the Code of Practice for the management and control of Panama disease tropical race 4 on an infested property in Queensland. This industry initiative was adopted under legislation by the Queensland Government and came into effect 1 July 2023.

AIternative crops may be grown successfully on blocks infested with TR4, however, the spores remain in the soil for decades.

Any movement of infected soil by machinery, equipment, tools, animals or people would still present a risk for other banana farmers in Queensland.

Strict biosecurity measures would still need to be implemented and maintained to prevent the risk of spread of TR4 to other banana farms.

Yes, but their level of resistance varies and most have other characteristics that result in them yielding significantly less than Williams Cavendish, the most popular Cavendish variety in Australia.

Currently there are about 10 Cavendish varieties in Australia with varying levels of resistance to PTR4. Some of these varieties have only recently passed through the quarantine system and are yet to be tested to determine their level of resistance and productivity. All of the varieties that have been tested so far have some deficiencies in yield compared to Williams or are not highly resistant and will eventually succumb to the disease.

There are also a number of nonCavendish banana varieties with varying degrees of resistance however, these varieties have not been fully evaluated for commercial production, post-harvest defects and consumer appeal.

All these varieties have come from overseas breeding programs and their eventual use for commercial production will require a licensing agreement with the agency or institution that conducts the breeding program.

There has been significant investment by the Queensland and Australian governments and the Australian banana industry to progress research and development projects that focus on developing banana varieties that balance resistance to pest and disease with high yield and good eating quality.

Research and breeding trials into genetically-modified varieties are also ongoing, however, it may take many years to identify suitable replacements for today’s commercial Cavendish crops

In Queensland the Biosecurity Act 2014 identifies Panama TR4 as a Category 1 restricted matter.

This means, diseased banana plants or plants suspected of TR4 must be reported to Biosecurity Queensland within 24 hours.

All people and business have a responsibility to protect the industry and limit the spread of the disease.

Read the Grower Kit for more information.

It generally takes two years for new varieties of bananas to pass through Australia’s post-entry quarantine facility, which makes sure exotic pests and diseases are not introduced into Australia.

Once passed by the quarantine facility, new varieties of banana plants are screened for resistance to disease. This process is estimated to take two years, then further research is needed to investigate production requirements, post-harvest issues, supply chain suitability and marketing potential.