The trade-off between breaking of dormancy of caryopses and revival ability of young seedlings of wild barley (Hordeum spontaneum)

Abstract

The relationship between breaking of dormancy of wild barley (Hordeum spontaneum C. Koch) caryopses and revival ability of young seedlings from a long period of desiccation was studied using barley caryopses stored for 2 years at 5°C and freshly harvested caryopses from a semiarid population in Israel. The 2 years of storage at 5°C significantly enhanced the germination percentages, but dramatically decreased the revival ability of the young seedlings from drought stress. There was a negative correlation between the breaking of dormancy of caryopses and revival ability. There were no significant changes in the effects of storage at a high temperature for periods longer than 5 days. The earlier germination occurred, the higher the revival ability of young seedlings from drought. The results suggest that breaking of dormancy might be at the expense of lowering the subsequent revival ability of young seedlings. The general premise is that a trade-off is expected between dormancy release of caryopses and revival ability of seedlings from drought stress, and that a treatment that aims at breaking dormancy must reach some compromise that optimizes the balance between the two traits based on the specific circumstances.Key words: dormancy breaking, caryopses, revival ability, seedlings, Hordeum spontaneum, wild barley.