Researchers fight frost from new fronts
Author: Bill Ryan | Date: 14 May 2014
Frost is the number one research priority that Western Australian growers continue to raise with Grains Research and Development Corporation (GRDC) panellists during our ongoing consultations.
It is a big issue for most parts of the WA grainbelt and can cost the State’s growers more than $100 million in years when frosts occur.
In recognition of production losses caused by frost in WA and other Australian cropping regions, the GRDC has more than doubled its financial commitment to research in this area to $3 million annually.
The GRDC’s frost investment focused until recently on understanding if there are genetic differences in frost tolerance between crop varieties.
To determine this, it was crucial to have a robust and rigorous method which could accurately identify differences in frost tolerance between varieties. Researchers were successful in achieving this.
The pioneering research, involving scientists including the Department of Agriculture and Food’s (DAFWA) Ben Biddulph, established that there are indeed differences in the ability of varieties to withstand milder frosts between -0.5C and -2C.
This has enabled researchers to work towards ‘ranking’ commercial cereal varieties according to their susceptibility to frost.
Dr Biddulph told WA growers attending recent GRDC Pre-Seeding Frost Workshops that they could expect to receive wheat variety recommendations for frost susceptibility in 2015, in the form of a ‘traffic light’ system.
A ranking system for barley is expected to follow later.
Despite these significant achievements in genetic frost research, the delivery of new varieties containing improved frost tolerance is still a number of years away.
Dr Biddulph predicts new barley varieties with improved frost tolerance will be available to growers by about 2020, and wheat by 2030.
The issue for growers in the meantime is whether there are practices they can implement that can reduce the risk of frost damage to their crops.
Subsequently, in addition to continuing to fund vital genetic frost research, the GRDC is investing in research looking at potential agronomic solutions to frost.
Initial work has included GRDC Regional Cropping Solutions Network (RCSN) supported trials which indicated that high stubble loads can increase the severity and duration of frost events.
Reducing stubble loads to about 2t/ha, using burning or raking, can boost wheat yields by 0.6-0.8t/ha in frost prone, low-lying areas.
This year, GRDC supported frost management research will investigate further the impact of stubble loads, with the aim of developing guidelines for frost-prone areas.
Other trials will look at the influence of stubble architecture and wider row spacings.
Even crop row orientation will be investigated. Are crops sown north-south versus east-west more susceptible to frost because of the way in which sunlight penetrates the crop row?
In addition to research focusing on genetic and management solutions, the third component of the GRDC’s frost initiative is looking at environmental factors - what I call the ‘science of frost’.
We don’t fully understand the physics of frost in the landscape - how it forms and where it’s going to hit.
Recognising this, there is a major effort underway to try to improve knowledge in this area.
This research will aim to understand how landscape features – such as shelter belts – affects the severity of frost.
More information about the GRDC’s frost investments is contained in the GRDC Ground Cover Frost Supplement which can be downloaded at www.grdc.com.au/GCS109
Information is also available in a GroundCover TV video at www.grdc.com.au/GCTV12-Frost