Molecules found in cholesterol medication could replace glyphosate to tackle herbicide-resistant weeds

A laboratory breakthrough could save the future of food production globally as weeds become resistant to current herbicides.

Farmers are battling increasing weed resistance to common broad-spectrum herbicides such as glyphosate, but Australian research could be a game changer.

The research by Western Australia's Curtin University Centre for Crop and Disease Management has focused on using molecules found in fungi, the same ones found in cholesterol medication, which could be as effective as mass-produced glyphosate.

Joel Haywood is the lead author of the research and has been working on the project for more than five years.

"As weed resistance increases, there are more issues for farmers and in yields and therefore we need new chemical compounds to overcome this resistance in weeds," Dr Haywood said.

Statins have been found to have a herbicide mode of action.(Wikimedia Commons: Malcolm Koo (CC-BY-SA-4.0))

How it works

The compounds that were found to work as a herbicide are called statins, and eradicate weeds by inhibiting an enzyme called HMG-CoA reductase.

When the enzyme is inhibited, it can kill the plant as it reduces cholesterol levels, lipids, vitamins, and other hormones.

"What we found is a very low dose or equivalent level to what you would spray glyphosate on crops, will kill plants by inhibiting that enzyme," Dr Haywood said.

The research found that statins worked well as a post-emergent herbicide when the leaves emerged from weeds.

Dr Haywood said there was potential for the molecules to be even more effective than glyphosate.

Glyphosate is one of Australia's most common weedkillers.(ABC Rural: Rose Grant)

Importance of new mode of action

The development would be a game changer according to growers like Ray Harrington who is a farmer from Cordering, 250km south-east of Perth.

He said a new mode of action was "imperative" for farming.

"If it is another glyphosate, that would be an absolute boom for world food production," he said.

"If it's successful, it will be a game changer."

There has not been a broad-spectrum herbicide mode of action introduced since glyphosate was first introduced nearly 50 years ago.

Certain plants have become resistant over time, and Mr Harrington said if this new herbicide was a glyphosate lookalike it could give the industry another 40 years.

Food production could be at risk without a new mode of herbicide action.(ABC Rural: Sophie Johnson)

"If we look 15 years down the track, I'm absolutely sure we'll have glyphosate resistance," he said.

He predicted that, with glyphosate resistance and no new mode of action, farmers would have to go back to cultivating the land for weeds.

He said WA's 15 million tonne grain average could drop back to 6 or 7 tonnes.

Hitting the market

It could take up to 15 years for the chemical compounds to get to market, however, Dr Haywood hoped to find more organic compounds, making the product available sooner.

"It could take a while for the new synthetic compounds to get through regulatory hurdles, however, if we find a new, natural statin, it could potentially be on the market within five to 10 years," he said.

"There's a lot of concern obviously, synthetic chemicals, just through perception on the general public.

"We're really excited about the potential for new natural products to come to market."