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°C, and in fresh, but incompletely hydrated seeds held at 20°C. We recommend seeds be held at-18°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.

Imbibition Temperature Affects on Seedling Vigor: In Crops and Shrubs

“…These results are evidence that imbibition temperature influences (1) moisture uptake, (2) seedweight loss during imbibition, (3) germination, and (4) seedling vigor. Recent work in our laboratory has found that the age of winterfat seeds influences the vigor response to imbibition temperature (Booth et al 1999). This raises the question of the effect of age on studies reported here.…”

Regulatory, Developmental and Tissue Aspects of Mitochondrial Biogenesis in Plants

“…It is then no surprise that mitochondria have been observed in plant embryos in seeds. In electron micrographs, the mitochondria of seeds appear to have a simple organization, with few membrane invaginations and the matrix contents are less dense than in mitochondria of established plants (Booth et al, 1999 [14] ). During imbibition and germination of viable seeds, mitochondria appear more like those in mature tissues (Treffry et al, 1967 [130] ; Booth et al, 1999 [14] ).…”

“…In electron micrographs, the mitochondria of seeds appear to have a simple organization, with few membrane invaginations and the matrix contents are less dense than in mitochondria of established plants (Booth et al, 1999 [14] ). During imbibition and germination of viable seeds, mitochondria appear more like those in mature tissues (Treffry et al, 1967 [130] ; Booth et al, 1999 [14] ). It appears these can arise from maturation of existing mitochondrial compartments, although replication of mitochondria also occurs, the onset of this being species-dependent (Bewley and Black, 1985 [11] ).…”