Teagasc entomologist Dr. Louise McNamara is encouraging growers to check their crops for the presence of pests, including grain aphids.

Speaking on the Tillage Edge podcast, she said that disease pressure can vary from different locations and between different fields.

McNamara said: “When Teagasc gives advice on these matters, it is general in nature – farmers must get to know their own fields and the disease pressures that can come to bear within them.

“It’s also important for farmers to know if a specific treatment has been effective. And the only way of finding this out is to walk crops on a regular basis.”

Checking crops for grain aphids

When it comes to monitoring cereal crops for the presence of grain aphids, a number of options are available.

Checking with the native eye is an obvious starting point. Another is the use of a small paint brush, which will pick up aphids as it is passed through a growing crop.

“Aphids can be identified using a suitable lens,” confirmed McNamara.

“Sticky traps and water bowls can also be used. But there are no thresholds in place to allow a grower discern the scale of the disease risk that exists, if aphids are found within a specific crop.

“The only conclusion to be arrived at is that the presence of any aphids at all represents a discernible BYDV threat.”

BYDV-related trials

In autumn 2021, Teagasc carried out a number of BYDV-related trials at Oak Park in Co. Carlow and at sites in Co. Cork.

Invariably, crops grown in the south of the country are more predisposed to the risk of BYDV.

“Significantly, the trial plots in Carlow had lots of BYDV, while those in Cork were pretty clear of the disease,” McNamara outlined.

“However, the other fields in the vicinity of the Cork trial were badly infected with the virus. The land used for the Cork trial was on a slight hill.

“We have had trial plots on hills before. However, on this occasion, the angle of the slope relative to the wind direction may have come into play. This is why it is so important for farmers to look at what’s happening in their own fields on a regular basis.”

Weather permitting, it is envisaged that significant acreages of winter wheat, oats and barley will be sown out over the coming days.