Chemical toolbox reduction…what’s the effect?

Steven Kildea – senior researcher in plant pathology – at the Teagasc Crops Research Centre in Oak Park – explained that fungicides are essential in Irish cereal production to control disease, while our climate allows for high-yielding crops which also results in high-disease levels.

“Our Irish climate gives potential for some of the highest yields in Europe, but it also results in ideal disease weather on these plants.”

What is chlorothalonil’s role?

Chlorothalonil is a multi-site fungicide – and is currently under review at EU Commission level – and Steven explained how it is used in Irish conditions.

“It’s important from two real aspects. The first aspect is control. It’s a very specific fungicide and it’s very effective at controlling diseases such as septoria on wheat and ramularia on spring and winter barley.

Winter barley at Oak Park

“From its second aspect, in terms of importance, it’s very important as an anti-resistance measurement.

It’s included with those higher risk resistance fungicides such as your SDHIs and azoles.

“We call it a multi-site, because it’s more than likely targeting a number of different targets within the pathogen, which means that it’s at a lower risk of resistance development.

If we’re not able to control these diseases as well as we possibly can they will reduce the capacity of the plant to capture sugars, so there would be a hit on yield.

Using trial data from a number of years Steven explained that the hit on yield could potentially be 17%.

“Depending on grain prices this could have a very significant effect on the net margin for the farmer,” he added.