Glassy State and Seed Storage Stability: A Viability Equation Analysis

Dry seeds exist generally in a glassy (or vitrified) state.The high viscosity of the glassy state would be expected tohave a retarding effect on deteriorative reactions in the cytoplasm.Thus the glassy state may be considered to be a biophysicalbarrier for seed deterioration. The present study aims to testthe hypothesis that seed storage stability is associated withthe glassy state. With the equations derived from the seed viabilityequation, we have calculated the maximum temperature (Tmax)for long-term storage of corn, pea and soybeans. The Tmax forlong-term seed storage is found to be in a good agreement withthe glass transition temperature (Tg) in each instance, suggestingthat seed deterioration would be accelerated when seeds arenot in the glassy state. Experiments with soybeans given acceleratedageing show that the loss of glassy state is followed by a rapiddecrease in seed viability. These observations provide indirectevidence that the glassy state may play a significant role inseed storage stability.Copyright 1994, 1999 Academic Press Glassy state, seed longevity, storage stability, viability analysis