Unusually high brown rust pressures affecting winter barley crops in Scotland should be factored into fungicide decisions this season, says Syngenta area manager in Scotland, Iain Lindsay.
Brown rust can be found in several varieties, he says, with weather conditions and crop growth having fuelled the fungal disease.
“Winter barley crops are much further forward than last season, and the thick crop canopies have created a microclimate that favours brown rust,” Lindsay explains.
“The weather wasn’t wet enough for high levels of the usual diseases of Rhynchosporium and net blotch early in the season, but this hasn’t been a problem for brown rust.
“Now that brown rust is in crops, it will be important to be on guard against it for the rest of the season.”
As well as being alert to brown rust in winter barley, growers should also consider the risks in spring barley crops, says Lindsay, particularly if the weather remains conducive.
He estimates that about 5-10% of spring barley crops were planted early in Scotland this season, during the dry February.
“Being in the ground for longer will make these early-drilled spring barley crops more exposed to disease.
“It would be prudent to consider all potential disease risks when planning spring barley fungicide programmes this season,” Mr Lindsay suggests. “Warmer conditions will help brown rust pressure during the summer.”
Source: Syngenta UK
