Scientists at the James Hutton Institute, in collaboration with the Division of Plant Sciences at the University of Dundee and the Fujian Agricultural and Forestry University of China, have discovered that the pathogen responsible for the devastating crop disease potato blight manipulates the plant's growth and development to boost its infection process.

Late blight played a major role in the historical Irish potato famine, and is still a huge problem for farmers today - causing massive crop losses and proving difficult to manage by chemical control and traditional breeding methods.

The fungal-like pathogen, Phytophthora infestans, secretes a protein into the plant called AVR2 which targets the plant's mechanisms responsible for normal growth and development. This protein, or "effector", can have an impact on the plant's growth and immune response, allowing infection to spread further through the plant.

Dr Eleanor Gilroy, a molecular plant pathologist at the James Hutton Institute and co-author of the study, said: "There are communication signals between growth and immunity systems in plants, allowing the plant to direct resources where they are needed most.

"The late blight pathogen has evolved to exploit this communication link, tipping the balance in favour of growth so that disease can progress while the plant's defences are low.

"This discovery reveals a novel strategy the pathogen uses to suppress the plant's immune system, highlighting a vulnerability in our crops that we could potentially target in the future to protect them from disease."

The role of effectors like AVR2 is not yet fully understood by scientists. Pathogens secrete them into plants during infection, and the interaction between effectors and plants may open further avenues to research crop pests and diseases responsible for enormous global food losses each year.

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Harrison & Hetherington Ltd sold 35 store heifers in Lockerbie on Tuesday to a top of 267p per kg and an average of 219.8p (-6p on the previous sale), while 17 store bullocks peaked at 251p and levelled at 228.4p (-4.5p).