The findings, now being studied closely in Whitehall, will keep the pressure on the Government over its GM policy. There is already a row over the significance and credibility of tests suggesting GM potatoes can harm rats, and other scientists have suggested that pollen from GM crops can cause contamination over great distances. The latest study, led by Dr Nicholas Birch of the Scottish Crop Research Institute, Dundee, will encourage campaigners wanting a ban on commercial growing of GM crops until detailed research on their effects on the environment are completed. It may also prompt new questions about the food chain for birds.
None is known to eat ladybirds, but several, including bluetits and warblers, feed on aphids.
Ladybirds are traditionally regarded as gardeners' and farmers' best friends and their well-being is a prime indicator of environmental stability. Environment Minister Michael Meacher has said he will extend a one-year voluntary moratorium on commercial growing indefinitely until he is confident there is no damage to the countryside or wildlife. The scientists involved in the latest research fed genetically modified potato plants to aphids which were in turn fed to ladybirds. Females were apparently affected more seriously than males and a change of diet to aphids not exposed to GM plants seemed to reverse the process. The researchers, who published their findings in the scientific journal Molecular Breeding, were funded by the Scottish Office, and included academics from Cambridge and Durham Universities.