An international team of scientists say disrupting the ability of insects to smell the scent of food and potential mates may offer a way to protect humans from deadly diseases such as malaria and agricultural crops from pests.

Lead researcher Faisal Younus from The Australian National University (ANU) and CSIRO said insects’ sense of smell played a critical role in the transmission of disease to hundreds of millions of people and the damage to food crops worth billions of dollars each year.

He said the research improved understanding of how insects process odours to find food and suitable mates.   

“The findings could help us to design better insecticides and find more efficient ways to reduce insect populations so they spread less disease and destroy fewer crops,” said Mr Younus, a PhD candidate from the ANU Research School of Chemistry who is funded by a CSIRO scholarship and based at CSIRO.

“The research will allow us to better understand fruit fly species like Drosophila suzukii, a major invasive agricultural pest that Australian government officials label as a serious biosecurity threat or ‘megashock’ if it ever enters Australia. These fruit flies have the potential to cause millions of dollars of damage in the fruit industry.”

Fruit flies like Drosophila suzukii lay their eggs inside fresh fruit and vegetables. The eggs hatch into maggots, which rapidly feed on the flesh of the fruit and vegetables, rendering them unsuitable for human consumption.

Mr Younus said insects had evolved a highly sophisticated olfactory system to smell odours.

“An insect’s sensory neurons are being cleared constantly at a very fast rate, ensuring their brain is not overloaded with odours,” he said.

“For the first time, we have confirmed the involvement of an enzyme that breaks down food odour molecules to help insects smell efficiently, and described the structure of this enzyme. Our study has also shed light on the crucial role the enzyme plays in re-priming the sensory neurons of an insect at a neurological level.”

Mr Younus said the research provided a highly promising molecular target to disrupt insects’ ability to sniff out potential mates, consequently reducing their populations so they spread less disease and destroy fewer crops.

ANU and CSIRO conducted this research with scientists at Université Pierre et Marie Curie (UPMC) and Institut National de la Recherche Agronomique (INRA) in France.  

The research is published in Scientific Reports.