Barley yellow dwarf is one of the most widespread and damaging viral diseases of grasses and cereal crops in the world. It can cause yield losses ranging from 5% to 80%.

The virus is transmitted by many aphid species including the bird cherry oat aphid, Rhopalosiphum padi, the grain aphid, Sitobion avenae and the rose-grain aphid Metopolophium dirhodum all acting as vectors for the disease.