Ramularia has the potential to reduce yield on winter barley by up to 1t/ha. On spring barley this figure ranges around 0.5-0.7t/ha. It’s a tricky disease that thrives when a few wet days come in a row and warm weather prevails, AgriLand’s Siobhán Walsh explains.
By the time ramularia shows its symptoms, the damage has been done. Preventative control is always best.
However, the chemical that provided the best control of the disease – chlorothalonil – cannot be used after May 19 next year (2020) and must be used up by this period where the product is in store.
This poses a problem for ramularia control. Next season, winter barley may escape the ban. Farmers might get their final spray on before May 19, when the use-up period of the product will end.
Over the past few weeks, AgriLand has seen a number of trials and talks on ramularia post chlorothalonil.
Advice on ramularia control at a recent open day in Ireland was to apply a preventative spray at GS45.
The alternative to chlorothalonil next season will be folpet – another multi-site fungicide – and down the road new chemistry will come on stream, but we also need to look outside the box.
Crop stress results in increased incidence of disease and so keeping on top of crop nutrition will be essential moving forward, as well as looking out for varieties which show some resistance to the disease.
There is no silver bullet to control of the disease, but as harvest draws in look at how your varieties and agronomy practices performed and think – what can you do to future-proof your yields without chlorothalonil?
