Maturity bronzing

Maturity bronzing - stretching the limits on fruit quality

By Ingrid Jenkins and Jeff Daniells

Several growers have reported a higher incidence of fruit affected by maturity bronzing in early 2023. In response to grower enquiries regarding what causes maturity bronzing and how to reduce its impact, it seems timely to give an overview of past research and recap on the best management options available to growers.

Maturity bronzing has been a long-term problem for Australian commercial banana producers, with research into the disorder dating back to the early 1970s in Australia. Much of the research was undertaken in Far North Queensland over 30 years ago by Jeff Daniells and other state government researchers at the time and has provided some interesting insights into what has proved to be a complex disorder. 

What we know:

Maturity bronzing is not caused by a disease or insect but is a more complex physiological disorder due to certain environmental conditions.

Figure 1: Maturity bronzing damage seen on top and fifth hands of the bunch.
Figure 2: Severe banana rust thrips' damage on all hands throughout the bunch

The disorder blemishes the peel of banana fruit close to maturity and appears as bronze-red/brown streaks or blotches usually on the outer curved surface of the fruit and is more prominent in the top hands (Figure 1). The blemish can first appear when a bunch is three-quarters to full maturity stage and worsens as the fruit continues to fill. The damage is to the peel only and does not affect the yield and eating quality of the fruit. In severe cases, it can cause corking/cracking of the peel. Its appearance makes the fruit unmarketable and can account for significant losses for growers.

The disorder is associated with periods of heavy rainfall, high humidity and overcast weather conditions leading up to harvest and is therefore worse at certain times of the year. In Far North Queensland the disorder is usually more prevalent in the latter half of the wet season from March to June. Water stress at the time of bunch emergence has been shown to increase the severity of maturity bronzing.

Research by Dr Michelle Williams from the University of Sydney has shown that the high growth rates in the wet season lead to the stretching of the epidermis (outer surface of fruit peel) which exceeds its elastic limit, leading to cracks and cell disruption in the peel surface. Disruption of the cells causes the release of the enzyme called polyphenol oxidase. Oxidation of this enzyme leads to the production of melanin, which results in the bronze-red/brown markings within the peel. It is the same process in many fruits; for instance, when you cut open an apple and get brown discolouration of the cut surface.

Dr Williams’ research also found low levels of calcium in the fruit peel and low cell number in the peel epidermis have been linked to the disorder. They also found low calcium levels present in fruit suffering from water stress near bunch emergence. This stressed fruit had more severe maturity bronzing. Subsequent trials looking to increase calcium in the fruit peel to lessen maturity bronzing were unsuccessful.

There have been several trials looking into the effects of different agronomic practices on the disorder.

Trials looking into the effect of bunch covering found that normal bunch covering does not worsen the disorder but, the disorder is made worse by fruit from sealed bunch covers.

Both bunch trimming and de-belling (removal of the male bud) increase the severity of the disorder.

It is possible to reduce the severity of the disorder by reducing the leaf number to seven or less from bunch emergence. However, this is counterproductive as bunch weight and fruit green life are reduced at the same time.

How to manage and reduce the impact of maturity bronzing:

• Maintain good soil moisture levels, particularly in the period within 2 weeks of bunch emergence. The critical         period is October to January, special attention should be paid to irrigation during this time. A high moisture           level should be maintained during bunch emergence.

• Maintain even growth in the plant and the bunch, particularly from 2-3 weeks prior to bunch emergence up           to harvest.

• Depending on market specifications, bunches can be harvested early before the disorder becomes severe.             Blemished fruit losses are minimised but there is a trade-off with lower bunch weight. For every week that a           bunch is harvested earlier, 7–10 % in bunch weight is lost.

• Improve drainage and light within your paddock to ensure bunches don’t take so long to reach a harvestable         grade. Waterlogging can be minimised by mounding rows and the construction of deep drains on alluvial soils       and light penetration can be improved by planting at moderate densities.

• Ensure bunch covers are not too long and not prone to sealing at the bottom of the bunch. If this occurs                 maturity bronzing will worsen.

If you would like more detailed information on past research into maturity bronzing, please contact the Better Bananas team at betterbananas@daf.qld.gov.au.


This information has been compiled as part of the National Banana Development and Extension Program (BA19004). This project has been funded by Hort Innovation, using the banana research and development levy, co-investment from the Department of Agriculture and Fisheries and contributions from the Australian Government. Hort Innovation is the grower-owned, not-for-profit research and development corporation for Australian horticulture.
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Richard Piper

Richard Piper

A career exploring the big world of tiny things

Richard is the man to talk to if you want information on insects in Bananas. Richard is a familiar face to many banana growers in Far North Queensland, having worked in the industry both in a private and government capacity for over 30 years. 

Over the past 5 years, Richard has worked as an entomologist with the Department of Agriculture and Fisheries (DAF) at South Johnstone. His work has encompassed screening of new chemistry for the control of bunch pests. These include synthetic as well as biological products such as fungi, bacteria and beneficial nematodes and botanical chemistries. Currently, he is continuing research on bunch pest management and spider mites, with a focus on integrated 

Meet a researcher
Richard Piper
Entomologist
Department of Agriculture and Fisheries
Centre for Wet Tropics Agriculture
South Johnstone

pest and disease management (IPDM) practices using a combination of existing chemistry with softer biological options.

Richard’s expertise is not only limited to bananas. He is often out in the field talking with growers about insect related problems in other crops grown in the wet tropics.

It’s not all about bugs though. The interaction between grower, industry and colleagues is what Richard enjoys most about his work. He is excited about the future in gaining a better understanding of the relationship between insects and plants. Richard considers finding biological options for control of banana bunch pests as an important part of his role, seeing an increasing need for softer alternatives for future management strategies.

Richard was born and raised at Manly on Moreton Bay and completed his early schooling there. He attended the University of Queensland, where he completed a science degree, majoring in entomology and botany and then completed his honours in entomology. He also completed a post graduate diploma at Gatton College in plant protection.

In 1984 he moved to Far North Queensland to take up a position working as a medical entomologist with Queensland Department of Health on the Dengue Program for four years, then took work with the Australian Army’s Malaria Research Unit for four years where he was based at Cowley Beach and employed as a mosquito collector. In 1990 he started work with the Department of Primary Industries on an integrated pest management (IPM) project which he did for four years before starting his own business, assisting growers to monitor and manage pest insects and other problems in the many crops in Far North Queensland. Twenty seven years later he returned to DAF at South Johnstone taking up the role of entomologist in 2017.

Richard’s favourite way of eating bananas is by mashing a banana, preferably lady finger, on toast and sprinkling it with brown sugar.

In his spare time, Richard likes to tend his extensive garden of tropical fruit and vegetables.

Sarah Williams

Sarah Williams

Bringing passion to bananas

Sarah Williams is a recent addition to the National Banana Development and Extension team. Having moved to the Cairns region, Sarah has taken up the role with the Department of Agriculture & Fisheries and is based at South Johnstone. Sarah will be working to assist growers by shaping research to address their concerns. Currently, she is focusing on determining methods to improve bunch pest management practices to reduce fruit damage, waste, and raise the bottom line for growers.

Sarah Williams
Development Horticulturalist
Department of Agriculture and Fisheries
Centre for Wet Tropics Agriculture, South Johnstone, Qld

Completing her university degree in Environmental Science at the University of Technology Sydney, Sarah spent her final honours year focusing on using natural rooting hormones from plant extracts to improve planting establishment, to reduce dependencies on fertilisers. After finishing university, Sarah knew that she wanted to work to bring science to the people, equipping them to make decisions with the most recent research. Moving from NSW to Ayr, Sarah began her career in extension working at an independent agronomy firm with the sugar industry, working on projects that focused on precision agronomy, herbicide efficiency usage and alternative fallow cropping. Here, Sarah discovered her love for working with local growers and helping them get the best crop possible.

We asked Sarah what she’s most excited about in her new role ‘ I’m really excited to provide the industry with research that’s relevant, practical, and address’ growers’ concerns and limitations within the industry.’

Outside of work, Sarah enjoys hiking, camping and playing with her dog. Her favourite banana recipe is rum-soaked BBQed bananas.

Steven Norman

Steven Norman

From vineyard to banana patch

Steve is supporting the NSW banana industry, working in the National Banana Development & Extension project with growers in the Tweed Valley, Coffs Harbour and Nambucca regions.

Steven’s experience in agriculture spans over a decade in several agricultural industries. Most of his experiences are in winemaking and vineyard production. His past work involved vineyard floor management, soil preservation, and viticultural techniques to produce unique flavour profiles.

Steven Norman
Sub-Tropical Horticulture Development Officer
NSW Department of Primary Industries
Wollongbar Primary Industries Institute
Wollongbar

In 2021, Steven took up a position as an Extension Agronomist with Farmacist in conjunction with Queensland Farmers Federation. Based in Mackay, he assisted in research looking at alternate plant varieties within sugar cane fallow crops, multispecies interrow companion planting, and investigations into different ways to capture and measure sediment runoff.

Steven is passionate about horticulture and seeing solutions to problems being found.

‘I see myself continuing in a position where I can listen to growers, plan and collaborate with them to deliver solutions. My motivations will always be to improve social, economic and environmental aspects within my focused industries’. In his role Steven is also working with other industries in NSW including blueberries.

A focus will be understanding where the growers in NSW are having difficulties or better understanding their challenges’

Steven enjoys a good banana bread, and his favourite recipe includes maple syrup to give it that extra sweetness.

Carole Wright

Carole Wright

Number crunching to help researchers understand their trials

Carole Wright plays a vital role in many of the banana trials conducted by Department of Agriculture and Fisheries. She works with researchers in trial design and helps make sense of their data. As a biometrician she develops and applies mathematical or statistical theory and methods to collect, organise, interpret, and summarise data to provide insight and meaningful interpretation of results. Carole is based in Mareeba and has been involved in banana research since 2008. She has applied her biometry knowledge to analyse a 

Meet a researcher

vast range of banana research including variety trials, bunch pest trials, nutrient rate trials, soil biology trials and crop timing, just to name a few. Carole also works with other industries and is currently developing a model to predict the meat fullness of mud crabs using near-infrared spectroscopy.

‘I get excited when I find something unexpected in the data that the researcher wasn’t necessarily looking for.  I enjoy the variety of work that comes my way and the satisfaction of extracting interesting conclusions from the data that excites the researcher’, Carole said.

Carole grew up in Hastings, New Zealand and attended Waikato University in Hamilton, completing a bachelor degree and Masters of Computing and Mathematical Science.  She worked in agricultural research for 5 years, before returning to university to complete a PhD. Her doctorate involved developing an algorithm to generate resolvable row-column designs which are often used to evaluate large scale field trials. She worked in Victoria, Northern Territory and England, prior to moving to Far North Queensland in 2008.


Carole says she is not renown for her cooking but finds banana and bacon cooked on the BBQ delicious.

In her free time Carole enjoys scuba diving and always looks forward to minke whale season.

Why is Banana Bunchy Top Disease so hard to eradicate?

Why is banana bunchy top disease so hard to eradicate?

By Dr. Kathy Crew and Dr. John Thomas

Banana bunchy top disease (BBTD) occurs in many locations throughout northern NSW and southern Queensland. The disease was first recognised in Australia in 1913 and by the mid-1920s had devastated the Australian industry, which was based in this region at that stage, causing losses of 90 to 95% of production. The research work of Charles Magee at the time revealed that the disease was caused by a virus (banana bunchy top virus, BBTV) which was transmitted by the banana aphid and in infected planting material. He devised a successful control program which enabled the resurrection of the industry. His strategy of inspection, destruction of infected plants, use of clean planting material, and quarantine remains the basis of BBTV control to this day. 

However, despite the generally low incidence of BBTD in the region today, occasional flare-ups still occur, and the virus has rarely been eradicated from a district. Despite the low incidence in many subtropical plantations, the virus remains a potential threat to the banana industry. Why is this so?

BBTV symptoms in an infected plant. Symptoms include stunted, upright, “bunched” leaves with upcurled, yellow margins and discontinuous dark green lines/dots and dashes are visible on the underside of leaves when viewed with transmitted light. Photo: K.Crew, DAF.

In his research, Magee was only able to transmit the virus by aphids when they fed on a symptomatic leaf. Excellent subsequent epidemiological and computer modelling work by Rob Allen predicted that aphids were only likely to spread the virus after about four new leaves had been formed on the newly infected plant. This allowed enough time for the infected plant to develop symptoms and for the aphid vector to acquire enough virus to be infective. The BBTD control program is based on inspection intervals timed to allow the location and eradication of most infected plants within this window.

The strategic levy investment project “Understanding the role of latency in Banana Bunchy Top Virus symptom expression” (BA19002) is part of the Hort Innovation Banana Fund. As part of BA19002, we have been studying an outbreak of BBTD on a plantation in northern NSW where the disease persists at a high level, despite the control program.

The banana aphid, Pentalonia nigronervosa. Adult aphids are about 1 mm long. Photo: J. Thomas, UQ.

By selecting “hot spot” areas in the plantation and carefully inspecting all plants in the area individually, stem by stem, we have shown that the inspectors’ high rate of positive identifications (>80%) is being maintained here. However, using laboratory tests on leaf samples from these plants, we found that BBTV was detectable in some recently infected plants before they showed symptoms. In other plants, the virus was detected in the symptomless leaf formed immediately prior to the first leaf to show symptoms.

This should not be a concern for disease spread if the virus was not transmitted from these symptomless, but infected, leaves. However, to our surprise, when we fed aphids on these leaves, the virus was transmitted to healthy banana plants. Furthermore, the rate of virus transmission was similar regardless of whether the aphids fed on infected leaves with symptoms or without symptoms.

The map shows a survey area where symptomatic (red) and pre-symptomatic (yellow) plants were located amongst the healthy (green) plants. We found that the virus was transmitted from thirteen symptomless leaves, eight of which remained symptomless over the whole three-week observation period.

Our next step is to determine whether these infectious, asymptomatic leaves are produced by BBTV-infected plants year-round or in a seasonally dependent pattern.

This plantation was poorly managed, with limited de-leafing, providing a sheltered environment for the banana aphids to multiply. De-suckering was also limited, thus providing more susceptible young plants (favoured by the aphid) that are often obscured by the dead leaf skirts. We suspect that the higher aphid numbers along with the higher number than expected of infection sources present as symptomless, infected leaves and obscured, infected suckers, combine to promote and prolong the epidemic.

Map of plants assessed in this study.
Checking the youngest leaf of each stem for symptoms. L-R: Dr Nga Tran, A/Pro John Thomas, Dr Mona Moradi Vajargah. Photo: K. Crew, DAF.
The laboratory testing team subsampling field samples. L-R: Dr Kathy Crew, Dr Nga Tran, A/Prof John Thomas, Dr Mona Moradi Vajargah, Dr Megan Vance. Photo: D. Baker.

Remember

•   BBTV-infected plants can be infectious prior to development of leaves with symptoms.
•   Removing newly infected plants promptly slows the spread of the virus.
•   Four-week inspection cycles during the summer months in high disease pressure situations can reduce but may not         completely suppress the outbreak.
•   Any reductions in inspection frequency will allow the epidemic to take off.
•   Plantations need to be well-maintained to limit aphid vector numbers.
•   Grower participation in detection and eradication between formal inspections is likely to have a significant beneficial 
     impact on control.     

More information

This research has been funded as part of the Improved Plant Protection for the Banana Industry Program (BA19002), which is funded by Hort Innovation, using the banana research and development levy, co-investment from the Department of Agriculture and Fisheries and contributions from the Australian Government. Hort Innovation is the grower-owned, not-for-profit research and development corporation for Australian horticulture. 
Support for the establishment of research sites and identification of infected plants has also been provided through Hort Innovation Project BA21003 “Multi-pest surveillance and grower education to manage banana pests and diseases”.

 

 

Banana bunchy top disease

Banana bunchy top disease

Banana bunchy top is considered the most serious viral disease of bananas worldwide

Banana bunchy top disease (BBTD) reduces the growth of banana plants and causes bunching of newly emerged leaves (Figure 1). Infected plants rarely produce fruit and are a source of inoculum for further spread, which can lead to serious commercial losses if not promptly eradicated. The disease is caused by a virus (banana bunchy top virus, BBTV) and affects all banana varieties. Unfortunately, there is no cure for the disease, once a plant becomes infected it must be destroyed as all parts of the clump/stool/mat are also infected. 

BBTD_Advanced BBTV symptoms
Figure 1 Banana plant infected with BBTV. Image shortening and bunching up of new leaves with yellow margins (photo courtesy of Australian Banana Growers Council)

BBTV is spread two ways, by banana aphids and infected plant material

BBTV is transmitted by a small black insect (1.5–2.0 mm long) called the banana aphid Pentalonia nigronervosa (Figure 2 & 3). Aphids that feed on infected plants can carry the virus spreading it to healthy plants as they feed. Aphids can carry the virus for several weeks and may cover large distances when blown by the wind. The virus can also be spread to new areas from infected planting material. It’s important to note that plants can be infected with the virus without showing symptoms. It’s always recommended that you source tissue cultured planting material from a Quality Approved Banana Nursery (QBAN) to minimise the risk of introducing serious pests and diseases onto your farm, such as Panama disease, BBTV, banana weevil borer and many more. Click here for a list of QBAN accredited nurseries. 

New research discovers new findings on virus transmission and explains why this disease is so hard to eradicate.
Click here for more information. 

Figure 2 The banana aphid, Pentalonia nigronervosa. Adult aphids are about 1 mm long. Photo: J. Thomas, UQ.
Banana aphids on banana leaf petioles
Figure 3 Banana aphids on banana leaf petioles.
BBTV_Ants and aphids
Figure 4 Ants and aphids living and feeding together. Image also shows numerous white cast skins of banana aphid (photo courtesy of Australian Banana Growers Council)

Control and containment activities continue to play an important role in limiting the spread of BBTV within Australia.

Banana bunchy top disease was first discovered in Australia over a century ago in the Tweed River region, located on the New South Wales and Queensland border. To date the disease has been successfully contained within the Bunchy top zone of South East Queensland and northern New South Wales. The banana growing regions of Far North Queensland, Northern Territory and Carnarvon in Western Australia remain free of the virus. However, it’s important for banana growers across all production regions to be on the lookout for BBTD symptoms. 

What to look out for?

Early symptoms of BBTD can be difficult to detect to the untrained eye. If you have stunted or unthrifty banana plants, examine the leaf lamina of the newest banana leaves for short dark green on lighter green dot-dash lines starting from, and sometimes extending or ‘hooking’ into, the mid-rib (Refer to photos below). You can see them best if you hold the leaf up to the light and look through from the underside of the leaf. There may also be dark green stripes running along the mid-rib. Plants with advanced infection have stunted looking leaves and a bunched appearance (bunchy top). If bunches are present, they may be small and deformed. 

Do not cut or disturb plants or move plant material off your property as this can spread the disease. 

Key symptoms

  • Dark green on lighter green, dot-dash flecks (sometimes called Morse code streaking/patterning) on leaves.
  • Dot-dash flecks are initially visible along the lower edge of the leaf’s midrib, then progress to the leaf veins adjacent to the midrib, and gradually becoming more prominent across the leaf blade. 
  • Eventually dot-dash flecks can form into irregular streaking. 
  • Leaf flecks and streaking are most visible when viewed from the underside of leaves.
  • Flecks in veins can form a characteristic ‘hook’ shape at the point where the midrib meets the leaf blade.
  • Vein-flecking can also be seen on the petioles and in the leaf sheaths of stems.
  • Growth of the whole plant is reduced and emerging leaves develop a choked or ‘bunched” appearance.
  • Affected leaves often appear more upright with pale yellow margins, and may have wavier leaf edges than normal.
 

ABGC have produced the following video on how to detect Banana Bunchy Top Virus symptoms in commercial plantations. 

How to report

It’s important for banana growers across all production regions to be on the lookout for BBTD symptoms.
Growers or members of the public that suspect BBTD must immediately notify their state’s biosecurity agency or through the bunchy top hotline 1800 068 371. Early detection and destruction are critical to limit its spread. Strict quarantine restrictions remain in place to prevent the movement of contaminated planting material.

Surveillance and containment work within the known bunchy top zone is continuing as part of Hort Innovation’s ‘Multi-pest surveillance and grower education to manage banana pests and diseases’ project, led by the ABGC. This important work is aimed at controlling and containing the disease within the known BBTV zone, supporting the commercial industry within this zone and aims to prevent its spread to other commercial growing regions within Australia. Click here to read more information about this project.

Currently, there is no cure for BBTV and there are no known resistant banana varieties. Control is only achieved through the destruction of infested plants and banana aphids. Early detection and destruction are critical to limit the spread of BBTD.

Latest research update

Click here to read about the latest new research that helps explain why banana bunchy top disease is hard to eradicate.

More information

In collaboration with ABGC, this information has been compiled by the National Banana Development and Extension Program (BA19004). This project has been funded by Hort Innovation, using the banana research and development levy, co-investment from the Department of Agriculture and Fisheries and contributions from the Australian Government. Hort Innovation is the grower-owned, not-for-profit research and development corporation for Australian horticulture.

Grower case study. Bagging technique improves fruit quality for Sellars Bananas

Grower case study

Bagging technique improves fruit quality for Sellars Bananas

Experienced premium Cavendish grower Naomi Brownrigg is confident that their bagging technique which leaves a ‘flue’, has improved fruit quality by reducing fungal and mould issues.

Naomi continues to see the benefit of this technique, implementing it on their family farm over 20 years ago.

Naomi says the flue bagging technique has dramatically reduced fungal and mould issues. ‘From that moment on (leaving a flue in the bag) we haven’t really had an issue. It will only be if the flue closes up you might get a mouldy bunch, after that we were free of it,’ Naomi said.

‘We’ve adopted that technique on our family farm for 20 years now and it’s so easy to do.’

Tianara Takai and Naomi Brownrigg from Sellars Bananas

Sharing lessons learnt for the benefit of industry

Naomi is passionate about helping other growers improve their fruit quality and is willing to share her knowledge and experience of lessons learnt. 

Sellars Bananas transitioned from bunch dusting with chlorpyrifos and talc to using a bunch spray with chlorpyrifos. This was to eliminate the risk of fruit being rejected at market due to talc residue. When they made the switch Naomi said they experienced significant decline in fruit quality due to increased fungal and mould issues. ‘At first we weren’t leaving any air hole (flue) in the bag. The bags did have perforated holes in them and we were just tying them up like normal and putting the spray in,’ Naomi said. It was her husband Dave who first noticed they had an issue ‘he said we have a huge problem out there. He said I can see all the fruit sweating and the mould starting,’ Naomi said. 
Naomi said the type of bags they used at the time also contributed to the problem, as they didn’t hold their shape and instead closed around the fruit. Naomi explained it’s important for growers to ensure the bags they use don’t close up. 
With chlorpyrifos currently under review by the Australian Pesticides and Veterinary Medicines Authority (APVMA), the permit to apply chlorpyrifos mixed with talc may be cancelled or not renewed once the current permit expires. This will leave only spray application of registered insecticides to control banana bunch pests. 

Some growers have reported increased incidence of mould and fungal issues using a bunch spray compared to dusting. It’s suggested that bunch spraying increases the amount of moisture in the bag and combined with high temperatures, may lead to increased humidity and fungal issues. Market agents have also confirmed fruit continues to be rejected due to talc residues. Naomi hopes that sharing their bagging technique will help growers who are currently experiencing fungal issues affecting fruit quality, and those who are looking at transitioning from dusting to bunch spraying in the future.

In light of the APVMA review and continued market rejections due to talc residues, Naomi encourages growers to start trialling it. ‘Now is the time to be trialling these things. People are getting rejected at the supermarket level for talc at the moment and that pressure isn’t going to go away,’ Naomi said.

Flue bagging technique

The term ‘flue’, simply refers to an opening. Its use in this circumstance is designed to increase air flow through the bag and reduce humidity.

The key points to the bagging technique used by Sellars Bananas are:

  ⦁ A liner is applied first to emerged bells and tied tightly around the bunch stalk with no flue (Figure 1).
  ⦁ At pruning, bags are tied with a knot tightly around the stalk, not wrapped. The excess bag is left open (Figure 2).
  ⦁ The bag around the opening is folded down on itself to improve integrity and stop it from closing.
  ⦁ All bracts are removed to further reduce moisture within the bag.

Figure 1 Bells are bagged early with a liner which is tied tightly around the stalk with no flue
Figure 2 Bags are applied at pruning and are tied tightly around stalk leaving a flue to the side

Sellars Bananas achieve control of rust thrips

When the banana extension team discussed this technique with growers, some have raised concern  the flue may provide an avenue for rust thrips to enter the bunch.

Naomi said this has not been their experience and believes that the bag being tied tightly around the stalk, acts as a barrier preventing rust thrips from moving down the stalk. In addition, the use of a liner, also tied tightly around the bunch stalk (without a flue) may help limit movement of rust thrips into the bunch.

Of course it is never one single practice in isolation and other bunch protection practices are also important for control of rust thrips. ‘If it has been injected on time, bagged on time and sprayed properly, we haven’t had a drama. We throw very little fruit away to rust thrips,’ Naomi said.

Figure 3 Sellars Bananas achieve good control of bunch pests and supply premium grade fruit

Every farm has different management practices and pest pressure and it’s therefore recommended that growers trial this bagging technique to make their own assessment before implementing it as a standard practice. 

Watch the video below for a demonstration of the bagging technique

Thank you to Naomi Brownrigg and the team at Sellars Bananas who provided their time and gave permission to use this case study for the benefit of the wider industry.

If you would like further information or assistance with bunch pest practices, please contact the National Banana Development and Extension Team on email betterbananas@daf.qld.gov.au or phone 07 4220 4152.

This case study has been produced as part of project BA19004 the National Banana Development and Extension Program which is funded by Hort Innovation, using the banana industry research and development levies, co-investment from the Department of Agriculture and Fisheries and contributions from the Australian Government. Hort Innovation is the grower-owned, not-for-profit research and development corporation for Australian horticulture.
 

Grower case study. Tiger Mereider has more than just his footbath covered.

Grower case study

Tiger Mereider has more than just his footbath covered

John Mereider, better known as Tiger, has been farming in the East Palmerston area for over 23 years. He is no stranger to biosecurity, having endured Panama disease race 1 on his farm when he grew Ducasse and some Lady Fingers in his early years on the block. Back then he built a drive through vehicle dip to help protect his farm. So, when Panama disease tropical race 4 was detected in Tully in 2015, Tiger didn’t hesitate in quickly putting more on-farm biosecurity practices in place to protect his farm. 

This included converting his existing drive through dip into an automated disinfecting spray down facility for vehicles. Pick-up and delivery trucks accessing the packing shed drive through this automated spray facility and are disinfected with Steri-max. These vehicles movement is restricted to the driveway to the shed and turn around area.

Tiger Mereider showing his covered footbath
Entrance to Tiger's farm showing biosecurity infrastructure

To address the risk of the driver’s footwear, Tiger installed a footbath next to the vehicle spray down. Tiger supplies drivers with a pair of boots to change into prior to using a covered footbath. 

Keeping it simple, Tiger purchased a 70 litre shallow plastic tub and a boot scrubber that he placed in the footbath. Because the footbath is not undercover, he had a stainless-steel lid built with a handle to place over the plastic tub. The lid ensures that the liquid does not evaporate when the weather is sunny or diluted when it rains. All up the covered footbath cost around $300. 

Another important consideration for Tiger was placing the footbath on a concrete surface to reduce contamination and make cleaning easier. He also painted large arrows on the concrete to direct traffic.

Tiger changes the disinfectant in the footbath every 2 weeks to ensure it is effective. He has used Quaternary Ammonium test strips to check the concentration of his footbath solution and is confident that it is doing the job when changed at this frequency. 

Tiger said, ‘The pickup and delivery drivers are good and always use the footbath, but I think it helps that I can see the footbath from the packing shed.’

In addition to his vehicle spray down and footbath, Tiger’s entrance to his farm is gated and clearly signed to limit unauthorised access. 

 

Simple footbath design with lid
Footbath located on hard paved surface

Thank you to Tiger Mereider for providing his time and giving permission to use this case study for the benefit of the wider industry. 

Tips on disinfectants!

  • Use disinfectant products containing Didecyl dimethyl ammonium chloride (DDAC) or Benzalkonium chloride (BZK). These quaternary ammonium (QA) compounds have been tested and solutions mixed as per the label rate do kill the fungal spores that cause Panama disease.

  • It is important to remove all soil and organic matter before applying any disinfectant product.

  • Easy-to-use test strips can be used to regularly test QA concentration of solutions in footbaths, spray shuttles and wash-down facilities. 

Click here for information on disinfectants.

If you would like further information or assistance with setting up or improving biosecurity practices for your farm, please contact the National Banana Development and Extension Team on email betterbananas@daf.qld.gov.au or phone 07 4220 4152.

This case study has been produced as part of project BA19004 the National Banana Development and Extension Program which is funded by Hort Innovation, using the banana industry research and development levies, co-investment from the Department of Agriculture and Fisheries and contributions from the Australian Government. Hort Innovation is the grower-owned, not-for-profit research and development corporation for Australian horticulture. 

Meet a researcher – Tegan Kukulies

Tegan Kukulies

From soil scientist to extension specialist: the focus has always been bananas.

Tegan has worked with the banana industry since graduating from university in 2009. Completing an undergraduate degree at James Cook University in Cairns, Tegan commenced her career with the Department of Agriculture and Fisheries working with renown soil scientist and nematologist Dr Tony Pattison. Under Tony’s mentorship, Tegan’s honours project looked at the effects of ground cover management on the biology of soils in banana production systems. Tegan continued working in the field of soil science for six years. 

Meet a researcher

Tegan Kukulies
Senior Development Horticulturist
Department of Agriculture and Fisheries
Centre for Wet Tropics Agriculture
South Johnstone

With a passion for the banana industry, Tegan decided on a career change taking on an industry development role in 2015, leading the banana industry’s National Development and Extension Project. This decision saw Tegan hitting the ground running, as commencement of her new role coincided with the detection of Panama disease tropical race 4 in Far North Queensland. Tegan played an important role as part of the incursion response, developing information packages and facilitating extension services for the banana industry. This also led to Tegan and the extension team developing an important resource for industry, the on-farm biosecurity best management practices guideline. 

Tegan is a local to the north Queensland area and was lucky enough to call Kurrimine Beach her home, growing up with all the beach and boating experiences the area has to offer. She now loves spending time with her young family, enjoying these and other outdoor adventures.

Tegan suggests you try a dessert pizza with Nutella, banana, and marshmallows.

Further to her experience in biosecurity extension, Tegan also leads key extension activities and initiatives for industry including banana roadshows, field days and workshops, NextGen activities, Better Bananas website, tailored on-farm biosecurity advice and assistance on general banana agronomy for growers.

Tegan Kukulies and Rob Mayers at banana industry field day at South Johnstone research facility.