The technology developed by researchers at the University of Sydney could revolutionize the management of agricultural losses due to mouse infestation.

In 2021, NSW Farmers predicted that the mouse infestation would cause $1 billion in crop losses in Australia.

The study, published in Nature Sustainability, was led by Ph.D. student Finn Parker, with co-authors from the Sydney Institute of Agriculture and School of Life and Environmental Sciences, Professor Peter Banks, Dr. Catherine Price and Jenna Bytheway.

According to the research team, spraying diluted wheat germ oil on a wheat crop before and after sowing reduces the mice’s ability to successfully steal wheat seeds by 63 percent compared to untreated controls.

Seed loss was reduced by 74 percent when the same solution was applied to the wheat field before planting. They claim the mice have figured out how to ignore the wheat smell by the time the crop is sown.

This disinformation strategy could be effective in other farming systems, as any animal that uses scent to locate food is potentially subject to our ability to manipulate that scent and compromise the animal’s ability to search.

Professor Banks said: “We could reduce the damage to mice, even during infestations, simply by making it difficult for mice to find their food by camouflaging the seed odour. Because they are hungry, they cannot spend all their time looking for food that is hard to find.”

He also said, “If the scent of the seed is all over the place, they’ll just look for something else instead of being encouraged to dig. That’s because mice are precise foragers that can sniff out seeds in the soil and probe exactly where a seed is. However, they can’t because everything smells like seeds. This misinformation tactic could work well in other cropping systems. Indeed, any animal that finds food by smell is potentially vulnerable to us manipulating that smell and undermining their ability to search.”

Finn Parker said: “The camouflage seemed to last until after the seeds germinated, which is the period of vulnerability in which wheat needs to be protected.”

He added that camouflage treatment could be an effective solution for wheat growers given wheat’s short-term fragility.

He said, “Most mouse damage occurs when seeds are sown until they germinate, a little less than two weeks later. Mice also cannot develop resistance to the method because it uses the same scent that mice rely on to find wheat seeds.

Most damage to mice occurs between the time the seeds are sown and germination, or just under two weeks later.

In May 2021, 60 plots on a farm 10 kilometers northwest of Pleasant Hills, New South Wales, served as a testing ground for five treatments.

The other three treatments were controls, while two used the wheat germ oil solution.

Similar results were achieved with all control treatments, which suffered noticeably more significant damage than treated plots.

A fairly affordable by-product of milling is wheat germ oil. The scientists claimed that their solution, consisting of wheat germ oil diluted in water, provides a safe, long-lasting replacement for pesticides and bait.

“If people want to control mice but can’t get the numbers low enough, our technique could be a powerful alternative to pesticides or add value to existing methods.” said Dr. Price.

The research could help wheat farmers at a crucial time.

The number of mice increases and wheat is sown in the middle of autumn.

The Australian wheat market is expected to reach a record high of $15 billion this fiscal year, according to the Department of Agriculture.

Wheat producers can benefit from the research at this critical time. Wheat is sown in mid-autumn and mouse populations increase.

The next step is for the researchers to determine how dilute the concentration can be and still effectively repel mice and how often the solution needs to be sprayed on a crop to maintain its effectiveness.

The Australian wheat market is expected to reach a record high of $15 billion this fiscal year, according to the Department of Agriculture.

Magazine reference:

  1. Parker, FCG, Price, CJ, BTW, JP, et al. Olfactory misinformation reduces wheat seed loss caused by rodent infestations. Nature Sustainability. DOI: 10.1038/s41893-023-01127-3