ESimple, non-toxic and apparently effective, spraying a dilute solution of wheat germ oil can drastically reduce mouse damage in wheat fields. Wheat seed losses fell by 63 percent on test plots when the researchers sprayed the solution between sowing and germinating the wheat. If the field was sprayed several days before sowing, the losses even went down by 74 percent. Apparently, the smell of wheat prevents the rodents from being able to specifically track down the seeds, explains the team led by Finn Barker and Peter Banks from the University of Sydney.
Rodents are responsible for the loss of an estimated 70 million tons of grain each year, the group writes in the journal “Nature Sustainability“. So far, however, pesticides and baits have been used – but with limited success and associated damage to the environment. As an alternative, the team is now using wheat germ oil, which is produced when the grain is ground and is inexpensive. It used it to spray wheat fields either during or before sowing.
Actually, mice would dig right where the seeds are
Source: Finn Parker
“This allowed us to reduce damage even during mouse infestations, simply by camouflaging the seed’s scent and making it difficult for the mice to find the food,” says Banks. Mice would rely on their keen sense of smell to locate the seeds in the ground and dig for them right there. “But when the smell of the seeds is everywhere, they move on and look for something else.”
The approach was tested on several plots of a 27-hectare test field – and during a mouse infestation with at least 300 animals per hectare. One hectare equals 10,000 square meters. The team sprayed the area either six days before sowing or just before sowing and then every two to three days until the seedlings appeared after about a week. Control areas either remained untreated or were sprayed with rapeseed oil. The damage after germination was counted based on the number of mouse holes along the seed rows.
More than six percent of the seeds were lost on the control areas, and at least 60 percent less on the areas treated with wheat germ oil, depending on the procedure. The authors emphasize that the amount of wheat germ oil sprayed can probably be significantly reduced. The frequency of the spraying action could also possibly be optimized.
“The misinformation tactic could work well for other crops as well,” says Banks. “In fact, any animal that finds food by scent is vulnerable to us manipulating scent and undermining their ability to forage.” This is a simple and ethical solution to dealing with agricultural pests.
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