Late sown spring barley crops are more prone to disease outbreaks such as Barley Yellow Drawf Virus (BYDV), according to Teagasc’s Michael Hennessy.

Speaking to Agriland, the Teagasc Crop Specialist said that 60-70% of spring barley crops have been sown in the last couple of weeks and are only starting to emerge.

“Basically all of the spring cereals have been sown, with the exception of a few stragglers,” he said.

BYVD is spread by the grain aphid and a disease outbreak can impact greatly on the yield of spring sown barley crops.

He said that these crops are emerging at the point of peak aphid activity and as a result are more prone to suffer from a BYDV outbreak.

A BYDV outbreak could result in a 40% drop in spring barley yield.

The Teagasc specialist said farmers should spray the crop with a suitable pesticide within four-to-five days of spotting the grain aphids on the barley plant.

However, resistance to chemical treatments is growing in the aphid population, he said and if the first treatment does not work farmers should change the pesticide used to control the grain aphid.

Fall in spring barley sowings

Hennessy estimated that the area of spring barley sown this year is down by between 5-10% on last year.

He continued to say that spring barley plantings have dropped, as winter barley plantings have increased.

Hennessy said that the area of winter barley has increased from 30,000 hectares to 80,000 hectares over the past 10 years.

Some farmers have also moved away from spring barley because of the low margins he said, and have sown grass and oil seed rape in its place.

The Teagasc specialist also suggested that the three-crop rule has impacted on the area of  spring barley sown, as farmers who had previously grown spring barley only had to change their cropping system to stay within the rules.