Blightcast warnings (UK) adapted to more aggressive blight strains

Potato growers and agronomists in he United Kingdom will be better prepared to cope with more aggressive blight strains this season, with a new BlightCast warning tailored to focus on infections now typically occurring earlier in the season at cooler temperatures.

The new forecasting model has been developed by Syngenta agromet specialists, to more effectively reflect the changing dynamics of today’s blight populations. The highly popular BlightCast five-day blight forecasting service, updated hourly on the Syngenta website and delivered direct to growers by email, will now feature a ‘New Criteria ‘ forecast, alongside a traditional Smith Period forecast.

The ‘New Criteria’ pinpoints forecast temperature to hit over 8°C and more than 11 hours at 90% humidity over two consecutive days to trigger a Blight Period, or a Near Miss where conditions occur for a shorter period. Syngenta Potato Manager, Andrew Curtis, highlighted that leading independent blight researchers are currently assessing these new cooler parameters as the conditions where they believe today’s blight strains may already be active.

“Whilst it is still subject to evaluation and further research, we wanted to make growers easily and quickly aware of these conditions, when hitherto risk was considered low but, in fact, blight may be infecting crops,” he said.

“It will enable them to time sprays more effectively and make better informed decisions on appropriate fungicide choice to prevent infection.”

The existing recognised Smith Period five-day forecast remains the primary information on the BlightCast website, with the secondary ‘New Criteria’ forecast and a five-day spray application window forecast – all based on the grower’s local postcode. “Using these tools in combination, growers can now assess the potential risk facing their crops and alter product choice of spray scheduling accordingly to ensure effective protection is in place,” advised Mr Curtis.