Dr Tim March (left) from the University of Adelaide and Dr Ben Biddulph from the Department of Agriculture and Food, Western Australia (DAFWA), pictured at the GRDC-funded frost screening nursery in Loxton (SA).
Grain growers in Victoria, South Australia and Tasmania will this year, for the first time, be able to factor frost susceptibility of wheat and barley varieties into their cropping programs.
Through the Grains Research and Development Corporation (GRDC) National Frost Initiative, most commercial wheat and barley varieties have been ranked for their relative susceptibility to spring radiation or reproductive frost, which occurs in late winter to early spring.
The rankings for frost susceptibility are being made available to growers and their advisers through the use of an interactive tool on the National Variety Trials (NVT) website at www.nvtonline.com.au.
With frost costing the Australian grains industry about $400 million annually in direct and indirect yield losses, particularly in the southern and western cropping regions, development of the rankings has been welcomed by growers and the broader industry.
Details about the new rankings have been delivered to growers and their advisers at recent GRDC Grains Research Updates.
Speaking at the Updates, Dr Tim March from the University of Adelaide said benchmarking current wheat and barley varieties for sterility at flowering under frost conditions in trials over recent years had enabled researchers to develop a ranking system in which varieties can be compared for their susceptibility to frost during the reproductive phase of development.
Dr March said the three years of data from the trials at GRDC-funded frost screening nurseries in Loxton (SA), Wickepin (Western Australia) and Narrabri (NSW) had shown that overall, barley was more tolerant to frost than wheat and that variation in susceptibility levels did exist between varieties under mild frost events.
“It is important to note that no varieties are completely frost tolerant,” he said.
Dr March said the new rankings were based on sterility measurements and not yield loss.
“So until we can get that data you should first select varieties for local adaptation, yield, optimal flowering time and other key target traits and criteria important for your farming system, and then use the frost rankings to fine tune your risk management of the selected varieties.
“In some cases, it may be that the more frost susceptible varieties are your best option. You don’t want to be on the back foot with yield before you get hit by frost.”
Dr March pointed out that the data used to determine the rankings was based on each variety’s relative susceptibility to reproductive frost at flowering, and not stem frost which occurs early in the growing season.
Assessment of the frost susceptibility of 72 wheat and 48 barley varieties has been carried out under the collaborative Australian National Frost Program (ANFP) which is a key component of the GRDC’s National Frost Initiative – an integrated program addressing genetic, management and environmental approaches to mitigate the effects of frost.
Dr March said breeding new cereal varieties with improved frost tolerance will be one of the solutions to minimising the economic losses resulting from frost, and ongoing research was focused on this goal.
“The GRDC’s investment in the ANFP is an example of a significant pre-breeding project which is developing industry capacity and methodologies that will enable not only the independent screening of newly-developed cultivars from commercial breeding companies, but also introduced germplasm to identify increased levels of frost tolerance for Australian growers,” Dr March said.
Dr March said it was important to combine genetic, management and environment strategies to overall reduce risk to frost.
“As frost exerts a complex production constraint in cropping systems, it requires a package of risk management strategies.”
To support growers and their advisers in their frost risk management efforts, the GRDC has just released a Managing frost risk – tips and tactics publication which is now available via the Managing Frost Risk page.
The publication offers advice on pre-season management tactics, management tactics within season, post-frost event management tactics, harvesting and marketing frosted grain, retaining seed from frosted crops and recovering from frost. It also provides links to other useful resources.
More information on GRDC’s National Frost Initiative and the new frost susceptibility rankings can be found via Ground Cover TV www.grdc.com.au/GCTV15-FrostRatings, the Ground Cover Frost Supplement, at www.grdc.com.au/GRDC-Video-NationalFrostInitiativePlaylist and the NVT website www.nvtonline.com.au.
Tim March, University of Adelaide
08 8313 6700
Sharon Watt, Porter Novelli