Dehydrins as stress proteins related to frost tolerance of barley

Dehydrins are stress proteins related to frost and dehydration tolerance. The aim of the paper was study of the polymorphism of the dehydrin genes (Dhn) in relation to the frost tolerance in barley. Primers specific for Dhn4 and Dhn7 gene sequences were used for length polymorphism analysis in 30 varieties. PCR products showed two different matrices; the first (O type sequence) was specific for six-rowed winter and intermediate varieties characterised by high frost tolerance and was typical of the Okal variety. The second type (A type sequence) was found only in two-rowed winter and spring varieties (e.g. Akcent) and was related to a lower level of frost tolerance. The length of the main polymorphic products corresponded to different alleles of the Dhn4 and Dhn7 genes. This difference in length was caused by the coincident presence of two specific mutations, i.e., an insertion of 6 bp in Dhn4 and a deletion of 30 bp in Dhn7 in O type barley varieties.