Disease threat spreading to East Anglia
16:21 17 August 2012
A serious threat to maize crops is spreading on the wind from the western half of England.
East Anglian-based maize specialist Neil Groom said that severe levels of disease have been detected in crops about a month earlier than usual.
The yield losses from maize eyespot could be the highest ever, said Mr Groom, technical director of Grainseed, of Langton Green, near Eye.
Significant levels of innoculum from last year combined with the poor growing season could lead to total crop loss in high risk areas unless rapid preventative action is taken,” he said.
“All maize growers should go and check their crops now to assess the presence of eyespot lesions in their crops,” he added.
“We’re seeing lesions a month earlier than expected in these areas and last year where no fungicide was used the eyespot came in before starch was laid down in the grain and the crop rapidly died off. Growers in these areas must spray now regardless of whether they think they have the disease.”
Even moderate levels of the disease can have a dramatic affect on maize production with 30pc reductions in yield not uncommon. “Infected plants show small roundish translucent spots with a light brown centre that merge together to form dead areas which reduce overall plant photosynthesis. And given the weather conditions and reduction on maize heat units this year, it is more critical than ever for producers to maximise green leaf area in the crop for as long as possible into the autumn to ensure optimum production of sugars and ultimately starch.”
There was a limited range of products available but most have used flusilazole successfully and it can be applied up to a month before harvest.
“Don’t worry about damaging the maize plants with the sprayer,” he added. “Many treatments will be carried out earlier than last year and the maize plants will be correspondingly smaller with younger, springier stems and the two rows which you drive over will come back up and not remain damaged on the ground. Obviously in tall crops it’s a job for a high clearance self propelled sprayer to get the booms high enough to get coverage across the field.”
Work done by the Maize Grower Association in 2009 proved the benefit of the recommended fungicides in keeping the crop green. “Eyespot is a growing threat to all UK maize producers and this year is an almost ‘perfect storm’ for its rapid expansion. All growers must be vigilant – it simply isn’t worth gambling with such an aggressive and financially damaging disease,” he added.