Mating-disrupting spray – a natural way to control crop pests
A naturally occurring mineral, zeolite, mixed with artificial bug pheromones, which are chemicals emitted by females to attract males, and other additives can inhibit pest mating behaviour when sprayed on crops. “This is a natural and sustainable way to protect plants against harmful pests because the pheromones the female pests use to attract the males are put on these carriers and dispensed over time,” explains Franz Reitbauer, coordinator of the project, Micro Dispensers for sustainable plant protection and founder and CEO of Lithos Crop Protect(opens in new window), based in Austria. “The zeolite carrier slowly releases the pheromones. The confused males can’t find the females, so fertilisation and reproduction are significantly reduced.” It does not kill the target pest but prevents them multiplying and harming field crops. “It is completely harmless for all other organisms, especially bees and other insects, but also harmless for humans and the environment for air, water, soil,” he adds. “Even natural pesticides create pest resistance, rendering them less and less effective. The only method known today that does not create resistance is mating disruption,” remarks Reitbauer. Mating-disruption pest control using synthetic pheromones is already in use in some vineyards and fruit orchards. But the plastic dispensers are manually distributed and attached to the plant. This is not economically viable for large-scale arable farming and row crops which are also the target of other EU-funded projects on pheromone-based crop protection such as PHERA. “We made mating disruption sprayable, so it is affordable, effective and easy to use,” says Reitbauer.
Micro dispensers using zeolite
The patented micro dispenser uses a finely milled zeolite as a carrier. “Zeolite acts like a sponge and it is able to bind cations [positive ions] so the pheromones stick to the fine zeolite particles. These two properties enable it to be used as a pheromone carrier,” he notes. “You can put it in water and spray it with normal field sprayers or drones.” “The fine 2-3 micron particles stay on the leaves and act like a dispenser for the pheromones,” Reitbauer explains, adding the sharp-edged particles are not easily washed off the leaves. A challenge for the project team was to ensure pheromone release for as long as possible. They succeeded in making the micro dispenser active for seven to eight weeks, increasing mating disruption and improving the product’s effectiveness.
Towards registration of a plant protection product
The project’s aim was to scale up the micro dispenser technology to a marketable product and develop new applications. The company already achieved proof of concept under the EU-funded CORNPROTECT project for use against the western corn rootworm (Diabrotica virgifera virgifera), an invasive leaf beetle that attacks maize roots, devastating the plant. The company’s formulation with the female rootworm pheromone as the active ingredient has been registered as a plant protection product, with regulatory approval expected in mid 2025. A distribution contract for Europe(opens in new window) has already been secured with Switzerland-based agri-tech company Syngenta(opens in new window).
More applications for different pests
The technology has also been shown to be effective against the fall armyworm (Spodoptera frugiperda), a moth larva that causes billions of euro of damage worldwide to crops, including corn, rice and cotton. Another formulation has been developed against Ostrinia or European corn borer, which affects corn. “We want to extend the technology in future to additional pests where mating disruption is possible based on their biology and behaviour, as well as identifying pheromones that can be adsorbed and slowly released,” Reitbauer says.
Keywords
Micro Dispensers for sustainable plant protection, Lithos Crop Protect, pheromones, PHERA, pesticides, zeolite, crop spray, western corn rootworm, fall armyworm, European corn borer
