Genetic control of cold hardiness and vernalization requirement in rye
Rye (Secale cereale L.) is recognized as the most cold-tolerant winter cereal species. However, little is known of the genetic control of cold hardiness and its interaction with vernalization requirement in rye. In the present study, the modes of inheritance of cold hardiness and vernalization requirement were investigated in crosses among one spring and two winter rye cultivars that represented a wide range of winter survivability. Differences in growth habit were found to be determined by a single dominant gene for the spring growth habit. Multiple alleles, or modifiers, for this major gene may also have been present. Cold hardiness was controlled by genes with mainly additive effects, but other factors may also have been involved. Cytoplasmic effects were not detected. Broad-sense heritability estimates were generally high (48–82%), indicating that selection for cold hardiness should be effective in breeding programs.Key words: Secale cereale L., dominance, additive gene action, heritability, cytoplasmic effects.