Pistachio productivity improvement program (PS17003)
What’s it all about?
Beginning in July 2018, this investment supports improvements in the cultivation of pistachios and the uptake of new and changing production practices through research, development and extension activities.
It supports the role and activities of a pistachio researcher who, in conjunction with other research associates, is tasked with undertaking ongoing field research that builds on the outcomes of earlier project Maintaining and expanding the technical development of the Australian pistachio industry (PS14000), which was funded by industry contributions through the then Horticulture Australia Limited.
Goals of the work include…
- Improving yields, through a better understanding of orchard management issues
- Benchmarking and reporting on quality and yield information to growers
- Assisting in disseminating information to growers, and in the adoption of R&D
- Supporting an increase in pistachio plantings
- Exploring new development areas for pistachio research
- Responding to any changing environmental and seasonal issues that may arise.
Data on the 2019 pistachio harvest has been collated and provided to individual growers as benchmarking reports.
Pistachios are extremely sensitive to lack of cold over winter, with lack of chill resulting in uneven and late harvest. To assist growers with this year’s crop, researchers used temperature data from the Bureau of Meteorology to develop a chill report for various growing areas up to June 2019. The report includes steps for growers to undertake so that they can boost yield should lack of chill be a prediction for the next season.
The research team prepared and completed a pilot trial to see if polymer application on orchard trees modified bud temperatures and assisted with yield. The trial began in August 2018 to test if lower temperatures in the last half of August result in lower blanks at harvest, as well as to ensure no ill effects on tree health from the polymer. Cooling polymer applications did increase nut set, and in one of the trial conditions it decreased the number of closed nuts.
In addition to providing support for the use of polymer, the small-scale trial indicated that nut set can be influenced by localised heat accumulation over winter. The effect is more pronounced in marginal chill districts or in low chill years. This is in line with similar observations in high chill lines of apples, cherries, nectarines and peaches. An extended trial using a larger number of trees will be the next step.
The work program going forward has been agreed upon and work has commenced on sub-projects including…
- Collecting data for a trial of Kerman
- Collecting information on pollen and nut quality
- Establishing data on Australian male trees including assessing pollen from each of the varieties
- A trial with the aim of increasing absorption of zinc.
Read the Chill Newsletter June 2019 to find out more about chill accumulation this season.
In September 2018, Dr Subhashini Abeysinghe was appointed to the role of Pistachio Researcher under this investment. Dr Abeysinghe, known as Subha, is an experienced field-based researcher with a PhD in agriculture from Charles Sturt University, a Masters in environment studies from the University of Melbourne, and many years of experience working with horticultural crops.
Subha was introduced to pistachio growers in November 2018, presenting at the spring Tech Group meetings facilitated by the project Technology transfer for pistachio growers (PS17002), and can be reached at email@example.com.
Research activities in the project have so far included the establishment of small trial looking at the use of polymers. The work is intended to see if applying polymers on pistachio trees can lower bud temperatures, and so assist with yield – also scoping the proposition that lower temperatures in the last half of August result in lower blanks at harvest.
Initial results have shown some benefits, but final results won’t be available until nuts are harvested and checked in 2019.
Other activities in the project have included…
- Reviewing previous research and scoping industry needs, to develop and begin implementing new industry research initiatives to benefit growers, under priority themes. These will grow to include mitigating the lack of chill, research into blanks, chemical work, variety studies, pruning trials and more.
- Communicating with growers, including through the channels of PS17002 and via farm visits, to support beneficial changes in production practices and to collect samples and information to feed into research.
At the time of writing this update, a pistachio researcher was set to be appointed – look out for further information in industry channels as it becomes available. It is expected that areas of research for the investment and potential sub-projects will include research into blanks, boron application, chill hours, the use of the modified central leader tree structure and more.
This project is a strategic levy investment in the Hort Innovation Pistachio Fund