‘Jekyll and Hyde’ bacteria offer pest control hope

But on certain plants, the relationship between insect and bacteria changes with the microscopic organisms exhibiting a disruptive ‘Hyde’ side. The insects grow and reproduce very slowly, while the bacteria themselves proliferate to very high densities in a short time — almost as if the bacteria were ‘betraying’ their hosts.

Further experiments have suggested that the factor triggering this strange change is the composition of nutrients in the plants where the creatures live.

The results, published in the Proceedings of the Royal Society B, may point the way to new methods to control aphids and other insect pests.

Professor Angela Douglas, of the University’s Department of Biology, said: "We now have the basis to explore precisely how these insect pests control their bacteria — and perhaps to develop ways to make the bacteria ‘turn nasty’ on the insects. These findings offer exciting new opportunities to control aphids and other pests without using insecticides."

ENDS

• The University of York’s Department of Biology is one of the leading centres for biological teaching and research in the UK. The Department both teaches degree courses and undertakes research across the whole spectrum of modern Biology, from molecular genetics and biochemistry to ecology. Its biomedical research includes an Immunology and Infection Unit (jointly with the Hull York Medical School), work on infertility and three research professors funded by Yorkshire Cancer Research and York Against Cancer.