FEARS that climate change will seriously affect crop yields in Britain by encouraging diseases are unfounded, scientists at Harpenden's Rothamsted Research have discovered.

Oil seed rape, the crop which carpets much of Hertfordshire in yellow in the summer, suffers from a disease that affects yield known as phoma stem canker, predicted to spread as the climate warms with with more carbon dioxide in the atmosphere.

But newly-published research by Rothamsted scientists shows that another disease, light leaf spot, will retreat with climate change, while yield loss from stem canker can be countered by treatment.

Overall, the new research predicts, yield will drop only slightly, and, through the use of disease prediction systems, could even improve.

Neal Evans of Rothamsted Research said: "Phoma stem canker is a global disease which is actually most severe in hot, dry countries such as Australia so one would expect the disease to be favoured by global warming. 

"In contrast, light leaf spot is favoured by cooler, moist conditions and so would not be expected to fare so well in the future.”