BYDV: The growth of a serious barley problem in the south-east

Most spring barley fields in the Wexford area are affected, to some degree, by barley yellow dwarf virus (BYDV) this year, according to Teagasc tillage advisor Ciaran Hickey.

“It can be as low as 5% of the field affected in some areas. But the average is more like 15%, with some fields up to 30%. At this level, there is an obvious yellow cast across the area.”

Hickey said that the scale of the BYDV challenge is set to grow.

The problem is now a real talking point with both feed and malting barley growers.

“The reality is that we now have a grain aphid population that is resistant to the pyrethroid aphicides that are currently available.”

The Teagasc advisor added that the BYDV challenge is more apparent in later-sown crops and those sown-out in sheltered, coastal areas.

“Farmers are now seeing the real scale of the problem as they drive through crops in their tractors. And they are deeply concerned that matters are only going to get worse.

“And this could very well happen if we were to have a late spring and April-planting was the order of the day.”

Hickey said that new chemistries to control aphids had failed to materialise. His feeling was that this may be due to the longer registration periods that are required to get new products onto the market.

“BYDV is a real yield-robber. The launch of a new aphicide had previously been expected for 2017. But this has now been put back. And I cannot say with any certainty when this new chemistry will come on to the market.”

Hickey confirmed that, in general terms, spring barley crops in the Wexford area are looking well at the present time.

“The scale of the BYDV problem is not large enough, as yet, to severely reduce barley yields. But the potential is there for serious problems to be created down the line.

“Tillage margins are tight enough. And the last thing growers need is to be confronted with another pest or disease-related challenge that can hit yields.

“Cereal growers are a pretty resilient bunch. They are always up for any challenge that confronts them. But, where BYDV is concerned, this is a battle which they cannot win at the present time, as they do not have the required tools in their lockers.”