Disease management in macadamia industry (MC12007)
Status: Ongoing project
What’s it all about? Established in 2012, this project brings together a team with extensive knowledge and contacts to deliver improved, sustainable and efficient disease management strategies for the macadamia industry. It has a broad range of work, from integrated disease management systems for husk spot, to the use of disease-resistant varieties, to investigation of emerging diseases of concern.
What’s the latest update? Disease management programs for husk spot and Phytophthora root rot were a key focus and success story for the project in 2016, with the industry reporting increased adoption of integrated management approaches for Phytophthora diseases in particular, including improved soil health management practices. This was the focus of the July 2016 round of industry MacGroups, and a macSmart video on integrated management of Phytophthora available on the macSmart website.
Recent work towards other project goals has included:
- Husk spot fungicide efficacy trails, with data from three seasons now analysed. Initial results suggest fungicides in the SDHI (succinate dehydrogenase inhibitor) group may serve as alternatives for husk spot control. Information was provided to DuPont Crop Protection Australia, with residue information and further data to be produced to support application for the registration of a new product with the Australian Pesticides and Veterinary Medicines Authority.
- Phytophthora and soil health research, with two large-scale commercial field trials assessing the impact of different soil organic amendments on root rot and tree decline. The researchers report that amendment treatments significantly reduced tree decline and increased average canopy density; adding that the results provide strong evidence to support a reduced reliance on pesticides for Phytophthora control, and a greater focus on key indicators for assessing soil health in orchards.
- Phytophthora susceptibility trials for macadamia varieties, with a wide variation in susceptibility to Phytophthora root rot revealed between species and hybrids of macadamia. Macadamia tetraphylla appeared to be more tolerant than Macadamia integrifolia, while Macadamia ternifolia was observed to be the most susceptible to root rot infection.
- Husk rot trials, which have been looking at the role of various treatments on disease incidence. Initial results suggest the chemical composition of the macadamia husk may play a role in husk rot incidence.
Throughout the project there has also been ongoing laboratory work, analysing disease samples from growers and consultants to identify pathogens responsible for various diseases in macadamia. Diagnostics feedback has been regularly provided to growers, and a presentation on major and emerging diseases was made at the Australian Macadamia Industry Conference towards the end of 2016.
Looking at the severity of Phytophthora root rot decay in different macadamia species and hybrids as part of project MC12007
Time of flowering and pollination relevant to orchard weather conditions in Northern NSW – a growers’ trial group (MC12011)
Status: Completed project
What was it all about? This project investigated the effect of weather events in the orchard on the success of pollination at time of flowering. It used grower-based trials to gather on-farm data in the Northern Rivers region of New South Wales (Newrybar, Knockrow, Rosebank, Alstonville Plateau and Tregeagle).
The final report for this project is due to Hort Innovation in March, and will be summarised in the next edition of Hortlink. When available, the full final report will also be available to order at www.horticulture.com.au/about/resources-publications-final-reports. Final reports are free to Australian horticulture levy payers, registered Hort Innovation members and industry representative bodies.
Biology, species and genetic diversity of macadamia lace bugs (MC13008)
Status: Ongoing project
What’s it all about? Macadamia lace bug (MLB) has a significant impact on the macadamia industry, but the taxonomy, genetics and ecology of the insect remains poorly understood. Established in 2014, this project is investigating key aspects of MLB including lifespan, food sources, where they lay their eggs and the like. The project will look at whether out-of-season flowering is driving outbreaks, and how far individual insects can disperse. It is also examining the genetics of the insect to determine whether there are ‘cryptic’ species infesting macadamias that may be overlooked.
What’s the latest update? The project continues to build a picture of MLB in Australia, collecting specimens to map the number of species and their relationships. Earlier in the project, a significant development had been the identification of two species of MLB new to science – one discovered in the Northern Rivers region of New South Wales and one in Tasmania. Since then, another new species has been identified from the Snowy Mountains.
Recent sampling work in the project has included the collection of MLB samples in Atherton and the Glasshouse Mountains in Queensland.
Importantly, analysis has revealed the MLB species that infests macadamias in Atherton is a completely different species to that found in southern Queensland or in New South Wales. It has never been collected outside of the Atherton region, and no host plant other than macadamia is recorded for it. The researchers note that because macadamias are not native to the region, this means there is potential for MLB to change host plants.
The field visit to the Glasshouse Mountains coincided with an unprecedented MLB outbreak, with some growers experiencing total crop loss within the span of a week. The species involved was found to be the novel Ulonemia “howardii”, whereas heavy infestations in the Northern Rivers were earlier found to be caused by Ulonemia decoris. The project team note this is the first time the undescribed Ulonemia “howardii” species has been recorded in plague proportions.
Other recent work in the project has included continued work to identify host plant species for MLB and continued genetic work, including research to understand the relationship between MLB species and other taxonomic groups.
Macadamia lace bug is the subject of study in project MC13008
Macadamia crop forecasting 2015-18 (MC15009)
What’s it all about? This project is responsible for producing macadamia crop forecasts each year, designed to be accurate to within 10 per cent of the actual final crop. It provides a tool for improved decision-making for macadamia businesses and the wider industry, and maintains an informed, viable and sustainable industry. Long-term forecasts will also allow planning for adequate infrastructure and industry marketing well in advance.
What’s the latest update? Work towards this year’s forecast continues, including surveys of macadamia growers and pest scouts, which are to be integrated into regional and overall totals for a growers’ forecast.
In 2016, the 52,000 tonnes in-shell (at 10 per cent moisture) crop was slightly higher than the project’s forecast of 50,000 tonnes, and represented an eight per cent increase on the previous year’s crop.
Benchmarking the macadamia industry 2015-18 (MC15005)
Status: Ongoing project
What’s it all about? This project supplies on-farm benchmarking information for the macadamia industry. By collecting planting, production, quality and other data and analysing trends across the industry, its ultimate goal is to allow informed decision-making and help facilitate improved farm productivity and profitability for macadamia growers and other stakeholders.
What’s the latest update? Work towards the 2016 benchmarking report continues. At the time of last reporting in Hortlink (Spring 2016), the Macadamia industry benchmark report 2009-2015 had been produced after analysis of data from the 2015 season together with yield, quality and other data dating back to 2009. The report remains available to download from Hort Innovation’s resource centre here.
Video case studies have also been in development, to highlight farm businesses where significant productivity gains have been achieved through investment in soil/tree health and orchard floor management.
Review of macadamia orchard nutrition (MC15012)
Status: Ongoing project
What’s it all about? This project has a focus on improving the quality of soil and plant-nutrition advice for the industry. It has involved the investigation of current literature on and approaches to soil health and macadamia nutrition, and the development of guidelines and protocols involving soil sampling, soil analysis, and nutrition timing, amounts and frequency.
What’s the latest update? The project was originally due to conclude in 2016, after its review of macadamia orchard nutrition was presented to industry. Following industry feedback, the project was extended into 2017 to facilitate a number of training workshops to further knowledge and understanding of soil and nutrition management. Provided to macadamia industry consultants and advisors, this training will ultimately improve the accuracy and consistency of advice provided to growers. The workshops will offer region-specific advice.
For growers, the key message is to work with your consultant to put an effective integrated orchard nutrition program in place to increase production and profitability. A full list of industry consultants is available on from the Australian Macadamia Society website here.
Macadamia regional variety trials – series 3, phase 2 (MC11001)
Status: Ongoing project
What’s it all about? This project is involved in the evaluation of new macadamia varieties previously established in earlier industry work. The information it generates will ultimately help guide growers in making decisions about new varieties for orchard expansion, development and possible replanting in key growing regions. The varieties it commercialises will have benefits including higher and more consistent production of high-quality kernel, resulting in a more profitable and prosperous industry in Australia, based on internationally competitive exports.
What’s the latest update? The project continues to maintain a number of trial sites, collecting and analysing data annually.
In 2016, eight regional variety trial (RVT) sites were harvested from March through to September, representing 30 blocks and close to 4900 trees. A 2kg sample was taken from every tree, with varieties in the trials comparatively assessed for 2016 kernel yield, cumulative kernel yield and 2016 nut-in-shell yield.
Kernel characteristics (including kernel recovery, size and quality, and pest, disease and environmental disorders), shelf life, roasting, oil profiles were also recorded as part of evaluations, as were tree size, flower characteristics and the use of Ethrel at trial sites.
Information collected through the trials is being used in the preparation of data sheets for the new varieties. The data sheets detail variety performance in the trials, compare characteristics to industry standards, and provide information of suitability for growing in various regions.
With results of the 2016 harvest discussed in December by members of the Macadamia Industry Variety Improvement Committee, four varieties – G, J, P and R – were deemed suitable candidates for commercial release. Their data sheets are available here:
Growers are now encouraged to submit an expressions of interest (EOI) for a limited release of budwood for early-adoption plantings of these varieties G, J, P and R. The Department of Agriculture and Fisheries (DAF) advises that preference will be given to growers who have access to rootstocks for immediate grafting and the two industry support nurseries (Ray Norris and Kim Wilson) for this first round offer. EOI’s should be submitted via email to email@example.com no later than March 6, 2017 for growers in Queensland and March 20, 2017 for growers in New South Wales.
In your email, state the number of trees of each variety you would like to plant, supply all business contact details including ABN, and who will be grafting/producing the trees.
DAF advises the cost will be $1.25 per stick. A royalty will also be payable as part of the commercialisation process. Growers can opt for a split payment of $2 per tree on planting and an additional $2 per tree on the sixth anniversary, or a $4 upfront payment. Growers will also be required to enter inter a non-propagation licence. If you have any questions about the process, please call Jodie Campbell at DAF on (07) 3708 8565.
Australian macadamia industry innovation and adoption program (MC15004)
Status: Ongoing project
What’s it all about? Beginning in 2016, this project aims to enhance the adoption of innovation and technology, and facilitate capacity building, in the Australian macadamia industry. It involves the work of a macadamia industry productivity development manager (MIPDM), Robbie Commens, who is responsible for a range of activities including:
- Regular grower meetings and annual consultants’ meetings
- MacGroup workshops
- Field days
- The production of communication materials such as videos and content for industry publications.
The MIPDM is also responsible for undertaking constant engagement with growers and the wider industry, management of emerging issues, and the identification and development of opportunities for new orchard territory and expansion.
What’s the latest update? Notifications for upcoming meetings and events under this project are distributed through Australian Macadamia Society channels, including the monthly e-newsletters.
In December 2016, the latest round of MacGroups included a harvesting strategy workshop as well as updates on pest pressures and integrated pest management. New MacGroup resources to come out of this included a harvest strategy checklist and a harvest strategy tip sheet with grower experiences. Videos of MacGroup presentations, and a harvest trial video, are also available to access here.
National macadamia grower communication program (MC15003)
Status: Ongoing project
What’s it all about? Beginning in 2016, this project is one vehicle through which knowledge and R&D and marketing outcomes are shared with growers and other industry stakeholders. The ultimate goal is to drive the adoption of new practices and technologies, and thereby increase orchard productivity and profitability. It also seeks to promote the Australian macadamia industry and its successes. The project works in conjunction with the Australian macadamia industry innovation and adoption program (MC15004) to form an integrated communications program for the industry.
What’s the latest update? A number of regular communication channels continue to be produced and maintained by this project, including but not limited to:
- The macadamia industry website, australian-macadamias.org/industry
- Quarterly Australian Macadamia Society news bulletins, containing key information and outcomes on levy-funded R&D and marketing outcomes, with issues available to download here
- Monthly industry e-newsletters (if you do not already receive these, you can sign up at the bottom left of the industry website
- A variety of ‘e-blasts’ (short emails) on a range of topics, such as regional updates, MacGroup invites and other urgent information
- Hard copy mail-outs as required, including event invitations
- Production and distribution of media releases promoting industry events and activities
- Biennial Australian Macadamia Industry Conferences.
Determining the extent and causes of abnormal vertical growth (MC15011)
Status: Near-completed project
What’s it all about? This project has drawn together a team of experienced plant scientists and a network of industry agronomists to update and consolidate research information on the threat of abnormal vertical growth (AVG) in the macadamia industry.
It has been looking at the current impact of AVG and potential causes of the disorder – including the role of biotic agents in its development and spread – and will provide recommendations for future research required for management, predictors and diagnostics.
What’s the latest update? The project is due for completion early this year, with a wrap-up of results to be provided in the next edition of Hortlink. Plans for a second stage of the project are also underway.
At the time of last reporting in the Spring 2016 edition of Hortlink, farms in all major growing regions had been surveyed for incidence and severity of AVG, including farms in Baffle Creek, the Bundaberg area, and the Atherton Tablelands in Queensland, and Mountain Top, Jiggi, Caniaba, and Hogarth Range in New South Wales.
The researchers reported that:
- AVG was more widespread and severe than in previous surveys
- Severe AVG symptoms were observed in varieties previously thought to be tolerant or only moderately susceptible to the disorder
- Irrespective of rootstock, HAES 344 trees were the most susceptible at all sites surveyed
- AVG status of 13 additional varieties had been determined, with six tentatively classified as tolerant
- AVG was observed in susceptible trees on various soil types.
Molecular analyses of AVG and non-AVG samples had also revealed the presence of geminivirus, bacteria and fungi in the samples, with initial observations suggesting an interaction between the geminivrus and bacteria in the progression of AVG. Work in this area was being progressed.
Other R&D projects of note…
- Hort Innovation is in the process of establishing an integrated pest management (IPM) program for the macadamia industry. This multi-project program will develop and extend knowledge and practices to support macadamia growers in having pest-resilient farming systems. So far, the project has a coordinator under Coordinator for the IPM program for the Australian macadamia industry (MC16003) and new projects established with three different service providers: The IPM program for the Australian macadamia industry – IPM Technologies (MC16006), The IPM program for the Australian macadamia industry – BioResources (MC16008) and The IPM Program for the Australian Macadamia Industry – NSW DPI (MC16004). Further projects are still to come, with more detail to be provided in the next edition of Hortlink.
- Macadamia second generation breeding and conservation (MC14000), which began in 2015 to progress genetic improvement for the Australia macadamia industry. It is working to produce new cultivars that will provide the industry an advantage over its international competitors. Specifically, the project is evaluating 3555 seedling progeny already established, and aims to increase the second generation population size by 10,000. Other significant activities of the project relate to the genetic control of husk spot disease and abnormal vertical growth, evaluating alternative breeding strategies, screening rootstocks for tree size control and productivity, and determining suitable pollinisers for elite selections.
- Biological husk spot research (MC12008), which is currently focused on the evaluation of biological control agent Macanizer for the control of the disease, and the subsequent production of a registration package for the product.
- Macadamia harvest improvement review (MC16001), for which Hort Innovation is currently appointing a service provider. The project will review harvest systems, processes, machinery and infrastructure in the macadamia industry to identify opportunities for improvement in harvesting.