Good News for Bees as Fungus Could be a Viable Pesticide

Investigating insect pathogenic fungi as a safe and natural alternative to chemical pesticides scientists from Swansea University, along with colleagues in Russia and Germany, have carried out studies* on a species of moth which is a pest in bee hives. This involved exposing 25 successive generations of the moth to a fungus called Beauveria bassiana.  They analysed the moths’ reactions to see if they built up resistance, but they also looked at other factors such as stress.

Dr Miranda Whitten from the Institute of Life Science at Swansea University said: “The big question with any pest control is whether insects will become resistant. Our research with fungi clearly shows that while insects do build up resistance, there is a very big price to pay.  Most importantly, they can’t breed as well.  Having their immune system on a high state of alert may be damaging to them, plus there is some evidence that they are more vulnerable to other infections.  Also the increased resistance applies only to that one fungus.   

All of these factors strengthen the case for fungus as a natural alternative to chemical pesticides.” 

“Although our experiments were on moths, it gives us an indication of what would happen in other organisms.  It provides a useful model to test things on. One of the key findings is that insect resistance isn’t just about the immune system.  The stress management system also plays a key role.  That’s why it’s important to look at the whole picture, not just immunity.” added Professor Tariq Butt from the university’s College of Science.

Dr Ivan Dubovskiy, from the Institute of Systematics and Ecology of Animals at the Russian Academy of Sciences in Novosibirsk, who was visiting his colleagues in Swansea, commented: “The research can help us make biological pesticides more efficient.  If we know more about how insects develop resistance to natural pesticides, it can help us unlock their defences.” 

*Published in PLoS ONE and the Proceedings of the Royal Society.