Published: 5 Jun 2020
During a free webinar this month (25 June, 2020), Dr Nigel Swarts will present outcomes for apple and pear growers from the Productivity, Irrigation, Pests and Soils (PIPS II) research project.
“Over the past four years we’ve been working on the PIPS II project with the goal of better understanding how apple trees use nitrogen and water for improved tree and fruit nutrition,” Dr Swarts said.
“The novel thing about this research is how we’ve gone about finding out the information. We applied a tracer that allows us to track the movement of nitrogen through soil and the tree, and then we excavated 28 whole apple trees and broke them up in a lab to determine exactly how nitrogen moves and is stored.”
The trials were conducted on orchards managed by Reid Fruits in the Derwent Valley, and Dr Swarts said the research could not have happened without the incredible support from industry.
“We need to work on commercial crops to conduct this research and Reid Fruits have been extremely generous in allowing us access to so many mature apple trees. It has made a huge difference to the outcomes of the trials,” Dr Swarts said.
As part of the project, the research team studied 31 different orchard blocks and conducted soil characterisation of apple growing regions across the country.
“We found that the way an apple tree uses water depends on the soil type. However, regardless of soil type, apple trees have a peak demand for nitrogen in a period approximately one month after full bloom through to just before the fruit comes off the tree,” Dr Swarts said.
“This means that to achieve better efficiency of uptake, growers can apply nitrogen at relatively low rates more frequently during this period rather than fewer large applications.”
Dr Swarts said that this approach could lead to improved fruit quality outcomes using less nitrogen over a season
“Apple growers are already very responsible users of nitrogen and are interested in these recommendations that could mean they can further reduce the amount of nitrogen they are using,” he said.
Dr Swarts will launch the Strategic Irrigation and Nitrogen Assessment Tool for Apples (SINATA) during the webinar. The user-friendly tool combines all the data collected on nitrogen and water use in apple trees with the soil characterisation work and will assist growers with using their resources as efficiently as possible.
“Growers will be able to use this tool to enter information about their tree age, variety, water availability, nitrogen strategy, and understand how this is likely to influence the orchard over a season. It will help growers to answer questions like ‘can I apply less nitrogen?’ or ‘what will happen if I only have this amount of water?’,” Dr Swarts said.
The webinar series is hosted by Apple and Pear Australia Limited (APAL) and is a substitute to the peak body’s annual industry forum and orchard walks which were cancelled due to COVID-19 shutdowns. The webinars provide an opportunity for producers to hear and question some of Australia’s and the world’s foremost apple and pear technical experts and to virtually visit local and overseas orchards.
Dr Swarts’ webinar will be held on 25 June from 9am - 10:45am. Register online here.
PIPS2 is funded by Horticulture Innovation Australia Ltd using the apple and pear industry levy funds from growers and matching funds from the Australian Government. TIA is a joint venture between the University of Tasmania and the Tasmanian Government.