CHRIS Preston has been studying weed resistance and dry-land farming in South Australia for decades, and says the world’s changing climate means more and more farmers across the globe will need to know the lessons he has learned.
The Associate Professor of Weed Management at the University of Adelaide sees the changing climate as a challenge for grain production in Australia, particularly changing rainfall patterns and shorter growing seasons.
“In comparison to farmers overseas, ours are at the forefront of managing dryland farming systems and there is much that overseas farmers could learn from a trip to Australia,” Preston says. “Longer term, there remain large areas of South America that can still be brought into crop production and significant production increases can occur in parts of the former Soviet Union.”
Preston says he recognised quite early in his career that herbicide resistance in weeds was going to be a significant driver of farm operations into the future.
The focus was on learning more about resistance and resistance management, so the researchers would know everything they could and be better positioned to advise farmers how to tackle the problem.
“One of the more enjoyable parts of the job is the appreciation provided by farmers for the work you are doing,” Preston says.
The results of his team’s work are now used extensively throughout south-eastern Australia. Some tactics they helped develop have been adopted in Western Australia and Queensland.
New Zealand has also looked at how Australia is addressing glyphosate resistant weeds and is adopting some of the approaches Preston has pioneered.
Preston also works in the United States on glyphosate and dicamba resistant weeds and says the work in South Australia has influenced the approaches taken to address these weed problems in America.
“Today herbicide resistance is dictating how many farmers grow crops. It influences crop rotations, weed management tactics and the focus on stopping seed set,” Preston says.
“It is one of the more important factors in decision making on farms.”
Preston is now working on emerging issues such as integrated management for multiple resistant grass weeds, including ryegrass and brome grass, glyphosate-resistant weeds and broadleaf weeds with multiple resistance.
He says their work on glyphosate resistance underpins much of the management of these weeds both in agricultural and non-agricultural systems throughout Australia and is being increasingly taken up in New Zealand.
“Our work with understanding the behaviour of pre-emergent herbicides in no-till systems has resulted in new chemical registrations in Australia, has been adopted by farmers in several areas and is now of interest to companies in Canada,” Preston says.
“Our work with integrated management of herbicide resistant ryegrass is also being adopted here in Australian cropping zones,” he says.
Collaboration with farming systems groups in South Australia and Victoria helps him get more trials in the ground.
As a result of their expertise in resistance and herbicide behavior, Preston does a variety of work with global chemical companies.
“Some of this is to provide advice about the development of resistance-management plans but we also work with new and old products – our interest is to try and get as much out of these products as possible,” he says.
With the soaring global population demanding more and more food every year, the pressure is on agriculture to get more - a lot more - out of less land.
Chris Preston and his team are the front line in that fight.