Potato growers can now be alerted to confirmed local blight outbreaks and Smith Periods, after the launch of the British Potato Council’s new combined Fight Against Blight (FAB) and Blightwatch service.
This will allow fungicide programmes to be better tailored to actual blight risk, says BPC agronomist Mark Prentice. “Early warning is a crucial part of keeping this devastating disease under control and reducing the annual £20m fungicide bill growers pay.”
There have already been a couple of blight outbreaks in crops under polythene in the south west and a number of Smith Periods have also been recorded, he says. “We don’t tend to get much traditional blight until most crops are through. Not many are yet and there’s not much inoculum about [due to the dry weather], but it’s early days, so there is no need to take your eye off the ball.”
Mr Prentice urges growers to stay alert for signs of the disease and control any volunteer potatoes or growth on outgrade piles. Outbreaks should be reported to your local agronomist, or email firstname.lastname@example.org
Trials aim to better target fungicides
A new set of BPC trials aims to improve blight control by more effectively targeting fungicide doses and timings. The trials will test how blight develops on three varieties with different resistance ratings, under a range of fungicide programmes.
Symphonia, which has good resistance, Maris Piper (moderate) and Shepody (susceptible) will be tested using spray programmes containing different rates of Dithane (mancozeb), Shirlan (fluazinam) and Infinito (fluopicolide) at seven and 10-day intervals.
“The products we have chosen represent the three new Europe-wide star ratings that fungicides are given – a standard which reflects their effectiveness and mode of action,” explains the BPC’s Rob Clayton. They also represent a range of costs, which will be built into the results, he notes.
Findings from the trials will be made available to growers as they progress. Last year’s fungicide trials can be found at www.potato.org.uk