Scientists block insects' sense of smell to protect crops
Good news for crop farmers this week with UK scientists discovering molecules they hope will confuse insects’ sense of smell and therefore their ability to detect plants – and each other. The researchers believe this could reduce the damage insects cause to crops and lead to better food security. Roughly one-quarter of the world’s crops are lost annually to pests and disease.
Lead researcher Dr Antony Hooper of Rothamsted Research, an institute of the Biotechnology and Biological Sciences Research Council (BBSRC) which funded the research, said: “One way in which insects find each other and their hosts is by smell, or more accurately: the detection of chemical signals – pheromones. Insects smell chemicals with their antennae; the chemical actually gets into the antennae of the insect and then attaches to a protein called an odorant-binding protein, or OBP. This then leads to the insect changing its behavior in some way in response to the smell, for example, flying towards a plant or congregating with other insects.”
Dr Hooper and his team studied an OBP found in the silkworm moth Bombyx mori, and were able to look at how it and a relevant pheromone interact. They also tested the interaction between OBP and other molecules that were similar to, but not the same as, the pheromone.
“As well as learning about the nature of this interaction we’ve actually found that there are other compounds that bind to the OBP much more strongly than the pheromone,” Dr Hooper said. “We could potentially apply these compounds, or similar ones, in some way to block the insects’ ability to detect chemical signals – the smell would be overwhelmed by the one we introduce. We’d expect the insects to be less likely to orientate themselves towards the crop plants, or find mates in this case, and therefore could reduce the damage.
“There is a lot of work to do from this point. We want to test this idea with important crop pests – we’ll probably start with aphids because they are a serious pest and we have some idea of what the aphid OBPs are like from the genome sequence. We’d also hope to apply our knowledge to insects such as tsetse flies and mosquitoes that carry human diseases. And ultimately we’ll look at developing ways to design suitable compounds to control these pests.”
“Around a quarter of crops are lost to pests and diseases and so if we are to have enough food in the future it is not just a matter of increasing gross yield, said Prof Douglas Kell, BBSRC Chief Executive. "To secure our future food supply we must look for new and innovative ways to prevent and control pests and diseases. This is an interesting finding that could be applied across a number of important insect pests and may have far reaching implications for preventing human disease as well.”
The team’s findings were published this week in Chemical Communication.