Rothamsted Research and Cardiff University develop new scent to repel pests and help crops

A breakthrough at Cardiff University in Wales might change how we think of pest control for crops.

Scientists at Rothamsted Research in collaboration with Cardiff University have developed artificial variations on natural scents that repel aphids, allowing crops to be “perfumed” to repel the pests and reducing the need for traditional pesticides.

However, another breakthrough happened entirely accidentally. One scent actually attracted the aphids. This could be used in trap-and-kill pest control schemes or to simply work in conjunction with the other pest scent to direct the aphids to another location.

“The ability of these new chemical compounds to modify insect pest behavior represents the possibility of moving pests away from crops and into traps or trap crops, in which pests are controlled by natural enemies,” said Michael Brickett, head of Chemical Ecology Research at Rothamsted.

These chemicals that affect the behavior of other organisms are called ‘semiochemicals’.

“I am really excited that this novel rational approach to discovering behavior-modifying substances is already unearthing molecules with unexpected activity,” Brickett said. “This has major implications for practical deployment of semiochemicals in crops.”

While the scents developed specifically targeted aphids, the theories behind them could be applied to other pest insects as well. Many pest insects can be redirected by the process used in enveloping these scents.

“Rothamsted has worked with scientists at the International Centre for Insect Physiology and Ecology in Kenya on devising a low-input, pesticide free system for growing cereals on subsistence farms in sub-Saharan Africa,” said Brickett. “The system, known as push-pull, has been adopted by thousands of African farmers and is being adapted for use in more challenging African climates.”

The next step in the development of these scents, according to Brickett, is to attempt to emulate other chemicals that affect insect behavior such as pheromones.

The work is published in the journal Chemical Communications.