National and local spread of barley yellow mosaic virus in the United Kingdom¹

Abstract

Barley yellow mosaic virus was first reported in the United Kingdom in 1980. Since then cumulative records of reports of disease, confirmed at the laboratory of the Agricultural Development and Advisory Service of the Ministry of Agriculture, Fisheries and Food, show how infection has spread from the east of England where it first occurred in quantity, to the west. Areas of concentrated infection appear to relate to areas of intensive winter‐barley cultivation. Records suggest that infection may have occurred as early as 1976. Patterns of local spread in fields as defined in aerial photographs reflect the means by which the viruliferous vector may be passively moved in the soil. Other patterns reflect previous cropping. The higher frequency of infection on the sites of long‐removed hedgerows is not explained.