Australia’s wheat producers are facing growing yield pressure as climate variability reshapes production decisions and expands the risk of frost damage, according to new research from the Commonwealth Scientific and Industrial Research Organisation.
The study found changing climate conditions are extending and intensifying the period when wheat crops are vulnerable to frost, adding another challenge for growers already balancing heat and drought stress.
CSIRO said frost can account for as much as $360 million in annual wheat production losses in Australia. The research, supported by the Grains Research and Development Corp., found late spring frost and earlier heat events continue to affect crop performance across the country’s wheatbelt.
Wheat is Australia’s primary winter crop, typically planted in autumn and harvested in spring and summer.
Researchers examined how current management practices are holding up under increasingly variable weather patterns. Those strategies include cultivar selection and adjusting planting dates so crops flower during the optimal flowering period, when the balance of frost, heat, water stress and nitrogen availability is most favorable for yield.
To evaluate those practices, the research team ran long-term simulations at 83 sites across the Australian wheatbelt using climate data dating to 1970 and multiple wheat cultivars.
The findings showed frost remains a major constraint on yields, even when crops flower during the optimal period. Researchers said this highlights the limits of current management approaches as seasonal conditions become more unpredictable.
The study also found growers often face difficult trade-offs. Adjusting production to avoid heat and drought can increase frost exposure during sensitive growth stages, while the combination of frost and heat stress can create the most severe yield losses.
Researchers said the findings reinforce the importance of phenology, the study of recurring plant life cycle events, as a key management tool. However, they noted it may no longer be enough on its own to offset the growing effects of climate variability.
The research suggests reducing crop sensitivity to frost could provide measurable yield gains, especially during difficult growing seasons.
Over the past two years, CSIRO researchers have focused on building frost tolerance in wheat by evaluating genetically diverse lines across multiple environments in New South Wales, South Australia and Western Australia.
The work also aims to improve understanding of environmental conditions linked to frost events, including humidity and dew formation, which researchers said are important factors in determining frost type and severity.
The study identified a gap in current frost management practices, which often rely on air temperature alone and may not fully account for canopy-level conditions where crop damage occurs.
Researchers said improving that understanding could help producers better assess frost risk and support the development of wheat varieties with lower sensitivity during critical growth stages.
Source: CSIRO, "Frost a challenge shaping Australian wheat production"