Evidence of cell deterioration in winterfat seeds during refrigerated storage

Abstract

Effective storage of wildland seeds helps alleviate supply shortages and mitigates variable production associated with annual weather patterns. The storage environment is critical for seeds like winterfat [Eurotia lanata (Pursh) Moq.] that rapidly lose viability under ambient conditions. Defining seed response to storage conditions is basic to effective seed storage programs. We used electron micrographs of freshly collected, and of stored winterfat seeds, with vigor tests to compare seedling vigor and to relate seed performance to seed cell biology as influence by; (a) seed age under known storage conditions, and (b) imbibition temperatures. We found that imbibition temperatures had little influence on the vigor of fresh seeds but significantly influenced aged seeds. Mitochondrial deterioration was evident in winterfat seeds stored 5-6 years at 5 degrees C, and in fresh, but incompletely hydrated seeds held at 20 degrees C. We recommend seeds be held at -18 degrees C or colder for long-term storage and that field seedings be done during the cold season to reduce the chance that incompletely hydrated seeds will be exposed to warm temperatures.