The Irish Farmers’ Association (IFA) has voiced its concern for the future of weed control after the first case of glyphosate-resistant grass weed in Irish cropping systems was confirmed.

The tests were completed based on both glasshouse assessments and a molecular analysis of the confirmed Italian ryegrass population.

Dr Vijaya Bhaskar, a researcher at Teagasc crops research department in Oak Park, published his findings on Tuesday 15 April.

IFA dairy chair Martin McElearney said: “It’s a concern for reseeding and down the line for all weed control.”

"Reseeding old pasture is a costly but important exercise on dairy farms. We need weedkillers that are effective at killing the old sward so that new swards have the best chance at establishment.

“We will work closely with Teagasc to assess the magnitude of this threat and provide guidelines for farms which may be affected."

This is the first confirmed case in Ireland, more than 50 years after the introduction of glyphosate.

Over 50 weed species worldwide have developed glyphosate resistance. However, this is mainly seen in orchards and vineyards.

In January, the UK weed resistance action group confirmed the first case of resistance to glyphosate in a UK weed species.

The resistance was also identified in a single field population of Italian ryegrass.