A five-year, $4.74 million study by La Trobe University will offer Australian growers sustainable alternatives to chemical-based weed management.
The project — led by Dr Ali Bajwa, senior lecturer in Weed Science and Agronomy in the Department of Ecological, Plant and Animal Sciences and the La Trobe Institute for Sustainable Agriculture and Food — will investigate the usefulness of Anaerobic Soil Disinfestation technology in Australia.
ASD involves the use of plant-based carbon sources, moisture and plastic soil coverings to create an oxygen-deprived — or anaerobic — environment that is hostile to weeds and soil-borne pathogens, causing them to die.
Once weeds are controlled, the soil microbiome can be returned to an optimal, oxygen-rich aerobic environment for growing crops, enhancing harvest quantity and quality.
ASD is in use in other countries but has not been trialled in Australia.
In the US it has seen a significant reduction in weed and disease pressure in horticultural crops and is being widely adopted.
The study will draw on this experience through a collaboration with researchers from Clemson University in South Carolina.
The project will analyse the effectiveness of ASD on a number of target crops grown on plastic mulch such as strawberries, capsicums and melons in Victoria and the Northern Territory, and determine the most effective carbon sources, treatment durations and application timing for the Australian environment.
Ali Bajwa said ASD was a low-cost yet sustainable, eco-friendly way of controlling weeds and soil-borne pathogens that had the potential for farmers to reduce weed infestations without the use of damaging chemicals.
“Fumigation with nasty chemicals is the main approach for controlling certain weeds and soil-borne pathogens in plasticulture-based horticulture crops in Australia at the moment,” he said.
“As more of these damaging chemicals get banned for use in horticulture due to environmental safety concerns, we will need a reliable alternative weed control approach that is good for the environment and achieves circular economy benefits by putting farm by-products to a great use.
“Our project will investigate the use of a broad range of carbon sources, including biowaste products such as chicken manure, rice bran, sugarcane molasses and cottonseed meal to create the anaerobic conditions needed for effective weed seed destruction.
“Ultimately, our goal is to determine the optimal combinations of bio-amendments and treatment strategies that would achieve the best weed control outcomes.
“We will work closely with growers, industry partners and extension groups to share our findings and drive adoption of this technology.”
The project is supported by funding from Hort Innovation, with co-investment by La Trobe University and the Northern Territory Department of Agriculture and Fisheries.
Hort Innovation research and development manager Dr Araz Solomon highlighted the significance of the project for the future of horticulture in Australia.
"This project represents an important investment in sustainable horticultural production,” he said.
“It forms part of a broader series of initiatives led by Hort Innovation, all aimed at improving weed management outcomes and delivering practical, science-based solutions that ensure the long-term success of the horticulture industry.”
La Trobe professor director Tony Bacic said the university was delighted to be partnering with Hort Innovation Australia to introduce new solutions to horticultural production systems.
“This program offers the opportunity to utilise sustainable and environmentally friendly solutions to weed control, as well as enhancing the profitability of growers by reducing input costs of production,” he said.
