UK: Smith Period blight alert set to be replaced

Now 60 years old, the current methodology for predicting blight pressure, known as the Smith Period, is set to be replaced by an improved alert system expected to be in place before the 2017 blight risk period. Following research undertaken by the James Hutton Institute and funded by AHDB Potatoes, the newly developed ‘Hutton Criteria’ was described as ‘a significant advancement’ over the previous system. John Sarup, agronomist and specialist potato adviser for SPUD Agronomy, said: “Late blight is a concern for potato growers every single year and a tool for identifying high risk periods of disease development is crucial to help us protect our crops and give us the confidence to schedule control activities at the right time, to the right level. “However, in recent seasons, blight has been found on crops even before any conventional Smith Periods had been recorded, meaning the current tools and systems just weren’t reliable enough to support precision decision-making.” AHDB-funded research by PhD student Siobhán Roísín Dancey, at the James Hutton Institute, examined relationships between reported outbreaks and recorded Smith Periods, and conducted experiments to determine new thresholds indicative of high blight risk. More