BYDV Management in Winter Barley
Barley Yellow Dwarf Virus or BYDV, is a virus that is transmitted by aphids and affects various cereal crops, in particular Winter Barley. BYDV is introduced into the crop by aphids flying into the crop & their offspring spread BYDV. Shane Kennedy & John Brophy, Teagasc Louth have more information.
As the name suggests, symptoms include short stunted patches of plants with yellow leaves. Yield losses can be severe and were up to 3.7 t/ha in recent Teagasc trials.
BYDV is introduced into the crop by aphids flying into the crop and their offspring spread BYDV throughout the crop. Once daytime temperature drops below 8ºC aphid flight is reduced and aphid mobility within a crop is reduced when the temperature drops below 3ºC.
BYDV risk is higher with earlier sown Winter Barley crops such as those planted in September. These crops will be exposed to milder temperatures for a longer period of time than those planted in October. Delaying sowing date will lower the risk and may eliminate or reduce the need for insecticide application. Clean stubble is another important IPM measure to eliminate green bridge transmission.
Before an insecticide is applied observe if aphids are present in the crop. If you find aphids or suspect that aphids are present apply a pyrethroid insecticide at the 2-3 leaf stage. After 5-7 days, check the efficacy of the insecticide. Presence of wingless aphids may indicate pyrethroid resistance. If this is the case contact your advisor.