Researchers Make Moves To Foil Frost

An innovative project at the Wagga Wagga Agricultural Institute is using mobile frost shelters in canola crops to boost the industry’s understanding of how time of sowing recommendations could help reduce frost impacts on yield.

In a bid to help save NSW canola growers a potential $63M a year in lost yield due to frost, a Grains Agronomy & Pathology Partnership (GAPP) pilot project, a co-investment by NSW Department of Primary Industries (DPI) and the Grains Research and Development Corporation (GRDC), aims to use the shelters to accurately quantify the yield losses.

NSW DPI crop physiologist, Rajneet Uppal, said special mobile shelters made from frost protectant cloth have been designed to cover trial plots and insulate plants from frost.

“In the past, we were unable achieve true frost exclusion in the field, now with these shelters we can exclude frost to quantify the direct yield loss and cost to growers,” Dr Uppal said.

“Results will be used to develop a greater understanding of frost impacts on optimum flowering dates and highlight production benefits in establishing canola at recommended sowing times.”

Dr Uppal said frost damage can occur when temperatures are forecast to fall below 2.0 °C.

“Our data loggers show temperatures at canopy level are two or more degrees below Bureau of Meteorology measurements made at 1.2 metres above ground,” she said.

“Frost events are more likely to occur in low-lying paddocks and areas with high stubble loads.”

Validated data on critical growth stages and temperature thresholds for frost damage can be used by growers to identify areas which are prone to frost and allow them to plan crop rotations accordingly.

Weather data indicates frost events are becoming more frequent and occurring later into the season, increasing the risk of frost damage to canola crops which have been sown early to avoid drought stress in spring.

In NSW, frost was estimated to have reduced the 2017 canola yield by close to 0.3 tonnes per hectare, a total of 120,000 tonnes valued at $63M at a farm gate price of $525 per tonne.