In Canada, the virus has occasionally been detected in pedigree seed, but losses caused by BSMV have been rare in recent years. Barley is the main host. On occasions it has been found in wheat and several grass species. The virus is seed-borne and is transferred from plant to plant when crop leaves rub against one another. Experimentally the virus can be transmitted by pollen, but since barley is self-pollinated this method of spread is generally of no consequence.
Infected seeds produce infected plants.
Seed from virus-infected plants is generally infected to a 60 per cent level. Disease builds up when infected seed is planted year after year. Damage Description Symptoms may vary with the virulence of the BSMV strain and time of infection. Infections appear as chlorotic mottling with spots or stripes of a yellowish color. Infected plants may be stunted and may mature later than healthy plants.