Growers can help combat fungicide resistance by diversifying their disease control tactics to include strategies such as stubble management, according to researchers from the Centre for Crop and Disease Management (CCDM).
Researcher Mike Ashworth says a CCDM project has quantified how much time and heat is required to kill fungal pathogens on wheat stubble.
Research agronomists Mike Ashworth and Leon Hodgson have carried out the research, supported by Curtin University and the Grains Research and Development Corporation (GRDC).
Dr Ashworth said that, following fungicide treatment of diseased crops, growers needed to ensure that any fungicide-resistant pathogens did not get a chance to infect following crops.
“Experience has shown that fungal pathogens, as well as weeds and insects, are rarely controlled using a single tactic and that fungicide over-reliance leads to resistance,” he said.
“The use of additional fungal disease management tactics will help prevent resistance from becoming an increasing problem and will also optimise crop yields.”
Dr Ashworth, who has conducted research into stubble management as a strategy to reduce disease loads, said laboratory work had recently quantified how much time and heat was required to kill fungal pathogens on wheat stubble.
“For example, pathogens will be killed by burning stubble for 40 seconds at 200°C,” he said.
“I have also used temperature probes to compare heat levels in windrows with those in standing stubble.
“This work has found that the burnt windrows retain high heat levels for much longer than burnt standing stubble, where the heat drops soon after burning begins.
“This research suggests that growers can effectively reduce the amount of disease inoculum between seasons by windrowing crop residues and burning these windrows,” he said.
CCDM research is also measuring disease levels in WA crops and finding that wheat grown on tall retained stubble is showing the highest amount of leaf area infected by fungal diseases.
Growers are not always able to cut low at harvest and CCDM aims to determine the ideal height to cut stubble in order to best reduce pathogen levels.
The CCDM was set up at Curtin University in 2014 to conduct cutting-edge crop disease research into genetics, breeding and fungicides, and to improve agronomy and farm management practices.
The GRDC has committed $30 million over five years to the $100 million CCDM as part of its long-term bilateral agreement with Curtin University signed in April 2014.
Dr Ashworth has returned to the Australian Herbicide Resistance Initiative (AHRI), based at The University of WA, taking up the GRDC-funded position of AHRI research agronomist, focusing on agronomic and technological opportunities aimed at achieving ‘more crop less weeds’.
Leon Hodgson, CCDM
08 9266 4818
Megan Meates, CCDM
08 9266 4818, 0437 538 541
Natalie Lee, Cox Inall Communications
08 9864 2034, 0427 189 827
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