22 November 1996

Experts meet to tackle blight

MORE effective blight control leading to reduced grower costs and less active ingredient use is the aim of a new pan-European effort to investigate the disease.

Some 30 experts from across the EU met in Holland last month to establish ways of producing a decision support system to help growers time sprays more effectively.

"Blight remains the major fungal disease of potatoes," says the Central Science Laboratorys Nigel Hardwick. "We have a handle on its control, but it can still ravage crops if it gets into tubers."

Farmers are understandably very cautious, so fungicide use is high, he adds. "Growers have little confidence in current Smith period forecasting systems. Often the stations used to obtain data are remote from potato-growing areas.

"Our three-year survey shows that crops were sprayed on average 6-7 times a season, though actual application numbers ranged from 1-17. Once the disease gets into a crop, you cant control it. Farmers tend to start very early and spray frequently."

A better forecasting system will allow better timing, reducing costs and the amount of active ingredient used, says Dr Hardwick. &#42