Identification Of Genes Deficient In Barley Mutants

Mutants are excellent tools for gaining insights into biochemical pathways, enzymatic reaction mechanisms, signaling networks and molecular processes in general. The Scandinavian barley (Hordeum vulgare L.) mutant collection located at the Nordic Genetic Resource Center, Sweden, is one of the largest barley mutant collections. With more than 11,000 entries, it is a fantastic resource for molecular studies connected to traits of applied and basic scientific interest.

In our research, we are especially interested in mutants with differences in day-length response, maturity, ripeness, chloroplast development, general plant size, culm length, culm stiffness and kernel size. The talk will focus on our recent results related to identification of genes causing a dwarf or semi-dwarf phenotype. Mutations in these genes are of importance for breeding of lodging resistant crop plants, an issue of growing importance in times of global warming.

Brassinosteroids effect cell elongation. Therefore, mutants deficient in genes encoding brassinosteroid receptors and brassinosteroid biosynthetic enzymes show a short-culm phenotype. We screened a collection of dwarf and semi-dwarf barley mutants for their response to exogenous brassinolide in a so-called leaf-unrolling test. We identified novel alleles of Uzu as well as new barley genes deficient in brassinosteroid mutants, which might be of importance for breeding of robust and lodging resistant barley cultivars.