title: The transfer of a powdery mildew resistance gene from Hordeum bulbosum L to barley (H. vulgare L.) chromosome 2 (2I).
abstract: Hordeum bulbosum L. is a source of disease resistance genes that would be worthwhile transferring to barley (H. vulgare L.). To achieve this objective, selfed seed from a tetraploid H. vulgare x H. bulbosum hybrid was irradiated. Subsequently, a powdery mildew-resistant selection of barley phenotype (81882/83) was identified among field-grown progeny. Using molecular analyses, we have established that the H. bulbosum DNA containing the powdery mildew resistance gene had been introgressed into 81882/83 and is located on chromosome 2 (2I). Resistant plants have been backcrossed to barley to remove the adverse effects of a linked factor conditioning triploid seed formation, but there remains an association between powdery mildew resistance and non-pathogenic necrotic leaf blotching. The dominant resistance gene is allelic to a gene transferred from H. bulbosum by co-workers in Germany, but non-allelic to all other known powdery mildew resistance genes in barley. We propose Mlhb as a gene symbol for this resistance.
authors.affiliation: New Zealand Institute for Crop and Food Research Limited, Private Bag 4704, Christchurch, New Zealand.
authors.forename: R A
authors.initials: RA
authors.lastname: Pickering
authors.forename: A M
authors.initials: AM
authors.lastname: Hill
authors.forename: M
authors.initials: M
authors.lastname: Michel
authors.forename: G M
authors.initials: GM
authors.lastname: Timmerman-Vaughan