It affects the economically important crop species barley, oats, wheat, maize, triticale and rice.

This process requires significant metabolic input from the plant, and causes the symptoms of barley yellow dwarf disease.

The symptoms of barley yellow dwarf vary with the affected crop cultivar, the age of the plant at the time of infection, the strain of the virus, and environmental conditions, and can be confused with other disease or physiological disorders.

The heads of affected plants tend to remain erect and become black and discoloured during ripening due to colonization by saprotrophic fungi.

By non-migrant wingless aphids already present in the field and which colonise newly emerging crops.

Insecticide sprays in this instance are therefore aimed at killing the aphids before significant spread can occur.