A relatively mild winter and more recent damp conditions have favoured development of powdery mildew, which has been identified in crops throughout the country.
Growers are being advised to incorporate a mildewicide in with the T0 fungicide, to avoid the infection spreading onto new growth.
Nigel Riches, arable technical specialist at Certis says: “With crops establishing well, we’re seeing thicker, lush canopies, which creates a microclimate for disease. What we’re starting to see is a lot of older crops heavily infected with powdery mildew, which then infects new leaves.”
“If we continue to see warm and damp conditions it could be a disease to really watch out for this year, particularly in coastal areas, in the north and west of the country.”
According to North East agronomist, Andrew Roy, Glacier, Tower, Infinity and Cassia are currently among the most severely infected barley varieties, while Leeds is one of the worst affected wheat varieties, although the disease is present in nearly all crops.
He says: “With this level of active disease, the case for a T0 fungicide application in barley is strong and plans are being drawn up as we speak.
“There is less urgency to act now with wheat, but as we get towards the T0 timing it may be sensible to add a mildewicide on lush crops with active disease, to prevent its progress up the plant onto yield forming leaves.”
For growers looking to control the disease at the T0 timing, Mr Riches advises using a fungicide that delivers both protectant and eradicant activity, in order to keep one step ahead of the disease.
High levels of the disease have forced some growers to consider a T0 application, even where the T1 is normally the first fungicide application.
Aberdeenshire grower, Graham Kindell has seen severe infection in a crop of KWS Tower, prompting him to apply a T0; something which he has rarely had to consider.
“If I don’t apply a mildewicide in the next couple of weeks, I can’t see the crop recovering and if I wait until T1, I think I would be chasing a lost cause and I would never really get on top of the disease.
“We get very cold winters up here and so there has only been a handful of times when I have had to resort to an early fungicide application, but this year, it is definitely justified,” he says.
While mildew is not considered the most damaging disease, growers are assured there is a lot to be gained from providing adequate control.
Mr Riches says: “Although the impact to yield is generally not as costly as we see with the likes of septoria, powdery mildew infection can still impact the bottom line, so it’s worth investing in an effective mildewicide.
“We always say that prevention is better than a cure, and making T0 applications a priority for the control of powdery mildew could be the difference between a good and a great crop this year.”