Barley yellow dwarf viruses: infection mechanisms and breeding strategies

Barley yellow dwarf virus infection (BYDV) often results in substantial yield losses in susceptible cereal crops. Major symptoms of BYDV infection in cereals include plant dwarfing and colour changes of leaf blades along the vascular bundles, especially of leaf tips. A full understanding of physiological and molecular mechanisms contributing to resistance provides salient information for breeding BYD resistant varieties and developing strategies to address the problem. In this paper, we reviewed BYDV infection mechanisms and summarised current information on known resistance genes, molecular markers and the use of transgenic techniques in breeding of BYD resistant varieties. Cereal yellow dwarf viruses (CYDVs) are also discussed as both BYDV and CYDV belong to the family Luteoviridae.