Photo: Colourbox

Pheromones in fight against pests

Food Biotechnology
A new non-toxic technology can prevent harmful insects from multiplying, thus reducing the use of pesticides in agriculture.

When the idea for the start-up—BioPhero—began to form in her mind three to four years ago, DTU researcher Irina Borodina never imagined it might become a commercial success. She simply wanted to make society more sustainable.

The idea behind BioPhero is to develop pheromone-based products that can be used as a substitute for chemical pesticides to combat pest insects in agriculture. The idea is to confuse the male insects with aromas, so they cannot find the female insects and mate.

Pheromones are signal substances secreted by organisms to other individuals of the same species. The eco-friendly pest control, which is based on the fermentation of yeast cells, will help create a sustainable agriculture that benefits our health and the environment.

“I think everyone should play a part in making society more sustainable. This is particularly evident when you talk to children, who ask: ‘Where does oil come from’, ‘why is there plastic in the sea’, and ‘why is fruit sprayed’?” says Irina Borodina, Director at BioPhero and who came to DTU as an exchange student from Lithuania.

Initial field studies
Irina Borodina is one of the female frontrunners at BioPhero. She and the rest of the team have developed the technology at DTU Biosustain in collaboration with researchers from Lund University in Sweden. BioPhero has received funding from Syddansk Innovation and has rented offices space at DTU Science Park. Researchers will now begin initial field studies.

“Our technology is aimed at producing biological pheromones. The pheromones currently available are chemical-based and expensive to make. This means that they are mainly used to combat pests in high-value organic fruit—e.g. grapes, apples, plums, and citrus fruits. When our technology is fully developed, we hope to be competitively priced with pesticides,” she says.

Instead of using chemical synthesis, researchers copy the female insects’ biosynthesis into yeast cells and cultivate them. In this way, yeast cells can produce a sex pheromone that is identical to the one that the female insects secrete to attract the males.

The biological pheromones are then mixed with a wax-like degradable mass which is sprayed onto the fields using ordinary spraying equipment. When the mass lands on the crops, it forms a small clump that quickly dries on the surface, signifying that the substance is protected from UV light and rain while the pheromone is gradually released over a period of several weeks.

The secretion of pheromones confuses the male insects, preventing them from mating with the females. Thus, insufficient larvae are created to destroy the plants.

End up on our dining table
Among other things, BioPhero will use the technology to protect rice paddies in Asia against pests. The insects consume the fledgling rice seedlings from the inside, thereby destroying the rice harvest.
“From a biodiversity perspective, it’s better to use pheromones than insecticides. Pheromones only work on insects of a given species and do not affect other insects. Insecticides, on the other hand, kill all insects and their natural enemies. The more you spray, the harder it is to maintain a balance in nature. If you only disturb a few pests, they don’t spread very much,” says Irina Borodina.

She believes we have exhausted the palette of chemicals that work on insects:

“Pest insects develop rapidly and become immune to insecticides—like the fall armyworm, which has invaded 28 African countries in the space of two years and is now on its way to Europe. The result is that farmers will have to use double and triple doses of toxic insecticides, which eventually end up on our dining table.”