A FRESH approach to providing potato blight risk information, should mean that this year’s Syngenta BlighCast will give growers a better opportunity to predict blight risks and tailor fungicide programme better.
Launched for the 2017 season on Monday, the web-based advice centre uses local weather forecasts and sophisticated disease modelling algorithms to predict blight risk for up to five days ahead.
But it also has three prediction models – one for conventional Smith Periods; a new criteria of blight development at lower temperatures and, new for 2017, a forecast using the Hutton Criteria, which models blight capability during shorter periods of 90% relative humidity.
Syngenta’s potato technical manager, Douglas Dyas, pointed out that websites or information systems that simply report historical data of weather conditions, when blight might have already infected, have a limited role in proactive disease management.
“With BlightCast you get prediction of blight risks with the chance to select appropriate strategies to prevent infection,” he said. “It has always been a forward-thinking system and has continued to improve to reflect developments in our understanding of the disease.”
He said frequent reports in recent seasons of blight incidence occurring in crops, even when weather conditions had indicated no Smith Periods. BlightCast is designed to be better equipped to reflect in-field conditions, where temperatures and humidity within a dense irrigated crop canopy, for example, could be significantly more conducive to infection and development.
“An improved understanding of risk allows growers to target fungicide timings for Revus to offer the best and longest protection from each application,” he advised. “It also remains crucial to stay fully aware of blight risk when attention turns to alternaria treatments.”
To further aid practical blight treatment programmes, BlightCast can also be used in combination with Syngenta’s spray window forecast – which indicates potential opportunities for in-field application over the next seven days.
“In recent years, many growers’ blight programmes have been severely disrupted by persistent strong winds or prolonged wet weather that has prevented application,” said Syngenta’s application specialist, James Thomas.
“If the spray window forecast sees problems arising, it can be the trigger to get preventative treatments on earlier and better utilise the long-lasting effects of Revus if future treatments are delayed.”
This also provides a guide to utilising low-drift nozzle technology to increase application opportunities in catchy conditions and get blight fungicides onto the crop.
Growers and agronomists can sign-up for the free Syngenta BlightCast at www.syngenta.co.uk/blightcast and if you are are covering large geographic areas, you can now register multiple postcodes for warnings.