A spray made from a biodegradable polymer capable of capturing and redirecting water to crop seeds could be the key to drought-proofing Western Australian farms.

A potential gamechanger for farmers battling declining rainfall, Murdoch University researchers have already demonstrated SMART SPRAYS on WA farms and aim to develop a commercially viable concept over the next few years.

Western Australia is home to a multi-billion-dollar agriculture industry, however, increasing drought due to climate change is wreaking havoc on crops and undermining food security, as well as the livelihoods and mental health of farmers.

Experts from Murdoch University’s Bioplastics Innovation Hub said in the Wheatbelt alone, winter rainfall had reduced by 20% over the past 25 years, foreshadowing real concerns about the region’s ability to produce vital food crops into the future.

Murdoch University Professor of Soil Microbiology and SMART SPRAYS, Maximising the Benefits from Rainfall project lead Daniel Murphy said helping farmers better capture rainfall could be hugely beneficial.

“If we can help increase water availability around plant roots, we could assist farmers in boosting crop productivity,” Professor Murphy said.

“Our drying climate is already presenting a big challenge for farmers and sadly we know this is only going to get worse.

“There is still more work to do, but SMART SPRAYS are showing potential as helpful innovation for farmers and we’re grateful for their interest in this project.”

SMART SPRAYS, Maximising the Benefits from Rainfall research officer, Cheryl Rimmer from Murdoch University’s Bioplastics Innovation Hub, said climate change was now one of the biggest challenges currently facing Western Australian broadacre farmers.

She said the SMART SPRAYS use a polymer derived from naturally occurring bacteria that helps soils capture rainfall that would otherwise be lost due to evaporation.

“WA produces about 45% of Australia’s wheat, and if we do get the declining rainfall duration and intensity that is predicted in the future, we potentially won’t be able to produce wheat,” she said.

“The substance used in the SMART SPRAYS naturally repels water. So, we're using those characteristics to form a spray to allow the rainwater to roll down the mound into the furrow.”

Samantha Viljoen, a PhD student at Murdoch University’s Bioplastics Innovation Hub, said the spray was completely biodegradable.

“They're from a natural product and we're just harnessing nature's ability,” she said.

“We are not putting any synthetic plastics into the soil, leaving no lasting legacy of microplastics or any chemical additives that are traditionally found in plastic mulches.”

Quarry Farms principal farmer Andrew Crook said producers needed to maximise every millimetre of precious rain that fell on their fields.

“Statistically, as most people would know, we are receiving less winter rainfall and more summer rainfall,” he said.

“The challenge has been how to harvest that summer rainfall event and store that moisture to make up the deterioration in winter rainfall, particularly in that transition spring-autumn period, where you're changing from summer to winter and the ideal time to plant our crops.

“That was a big challenge, adjusting all of those to better make use of rainfall events.”

Led by Murdoch University, the SMART SPRAYS, Maximising the Benefits from Rainfall project was supported by the Growers Group Alliance’s South-West WA Drought Resilience Adoption and Innovation Hub (SW WA Hub), through funding from the Australian Government’s Future Drought Fund, the WA Agricultural Research Collaboration (WAARC) and Murdoch University. This funding allowed the team to demonstrate the concept to farmers and confirmed their interest in the project.

Tanya Kilminster from the SW WA Hub said the SMART SPRAYS had the potential to be transformative for farmers.

“We've dropped nearly 20% of our winter rainfall in just this region alone in the last 25 years. So, if we've got technology or an innovation that can harvest more water and reduce evaporation to get the seeding bed right to grow more plants, biomass, and then yield, that's a winner,” she said.

Now that the demonstration phase is complete, Murdoch University researchers, with support from the Grains Research and Development Corporation (GRDC), will begin developing a commercially viable product that can be made available to broadacre farmers.