Journal of Applied Genetics 45(2), 2004, pp. 145-159

Molecular markers in breeding for virus resistance in barley

Frank ORDON, Wolfgang FRIEDT, Konstanze SCHEURER, Bettina PELLIO, Kay WERNER, Gisela NEUHAUS, Winfried HUTH, Antje HABEKUSS, Andreas GRANER

Abstract: The soil-borne barley yellow mosaic virus disease (BaMMV, BaYMV, BaYMV-2) and the aphid-transmitted barley yellow dwarf virus (BYDV) are serious threats to winter barley cultivation. Resistance to barley yellow mosaic virus disease has been identified in extensive screening programmes and several recessive resistance genes have been mapped, e.g. rym4, rym5, rym9, rym11, rym13. In contrast to barley yellow mosaic virus disease, no complete resistance to BYDV is known in the barley gene pool, but tolerant accessions have been identified and QTL for BYDV-tolerance have been detected on chromosomes 2HL and 3HL. The use of resistance and tolerance in barley breeding can be considerably improved today by molecular markers (RFLPs, RAPDs, AFLPs, SSRs, STSs, SNPs), as they facilitate (i) efficient genotyping and estimation of genetic diversity; (ii) reliable selection on a single plant level independent of symptom expression in the field (iii) acceleration of back crossing procedures; (iv) pyramiding of resistance genes; (v) detection of QTL and marker-based combination of positive alleles; and (vi) isolation of resistance genes via map-based cloning.

Key words: barley, barley yellow mosaic virus disease (BaMMV, BaYMV, BaYMV-2), barley yellow dwarf virus (BYDV), resistance, breeding, molecular markers.

Correspondence: F. ORDON, Institute of Epidemiology and Resistance, Federal Centre for Breeding Research on Cultivated Plants, Theodor-Roemer-Weg 4, 06449 Aschersleben, Germany