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Abstract PremiseSeed longevity is critical for successful genebanking, but it is hard to detect or predict. We examined survival of genebanked seeds from species native to the United States to estimate longevity. We tested whether RNA integrity (RIN) can be used to detect aging and predict mortality. MethodsDry seeds from >100 species were stored for 28 ± 7 yr at −18°C. A recently harvested sample (cohort) from the same population provides a zero‐time reference. Germination and RIN were assessed and differences between cohorts were used to distinguish short‐lived seeds from long‐lived seeds. ResultsNo differences in germination or RIN were detected between cohorts in about one‐fourth of the species. Viability and/or RIN was lower in the stored cohort than in the recently harvested cohort in most species, and the size of the difference was used to infer aging rates. Differences in germination and RIN were correlated among the 100 samples tested; moderate correlation coefficients indicate that additional factors are involved in seed aging and its detection. ConclusionsOverall, longevity in the genebank appears to be similar for seeds from wild and domesticated species. We identified species that appeared to produce quite long‐lived and short‐lived seeds. Seeds from wild species tend to germinate slowly and asynchronously, and this confounds comparisons across storage times; deterioration is detected mostly after severe mortality. By contrast, RIN values decline before viability loss is detected and appear to be unaffected by wild seed traits. RIN tests during early storage can help predict seed longevity.
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Assessing the RNA integrity in dry seeds collected from diverse endangered species native to the USA
IntroductionDry seeds do not show obvious signs of life and so testing for viability, health and life expectancy can be challenging. Usually testing seed quality involves adding water and measuring metabolic capacity or growth potential by vital staining or germination assays. Importantly, most laboratory seed tests are intended to assay immediate viability, while most genebanks need tests that predict seed performance in the distant future. All currently available assays require considerable a priori knowledge of germination conditions and seeds large enough to dissect. Germination conditions are often unknown for seeds produced from wild species and are an important criterion for seed testing. MethodsUsing standardized methods (i.e., commercially available kits) we tested the feasibility of adapting a new seed quality assay that measures RNA integrity and is promising for cultivated species, to seeds from wild species. Most of the 100 wild species we include are rare or endangered and in need of preservation through genebanking. To determine the feasibility of measuring RNA integrity in seeds from wild populations, we compared the quality of RNA extracted from seeds that were recently harvested to those of the same species that have been genebanked for 16 to 41 years, with various seed traits examined for interference with RNA extraction and characterization. ResultsWe demonstrate reliable characterization of RNA quality across a diverse group of plants, despite variation in germination requirements, seed morphology or composition. RIN (RNA Integrity Number) values were usually high across all samples and variables, attesting to both the quality of newly collected material as well as its maintenance under genebanking conditions. This study conclusively demonstrates the feasibility of reliably extracting and characterizing RNA from dry seeds collected from wild populations, regardless of a variety of seed traits and morphologies. Relationships between RNA quality and seed age and viability require further exploration.
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- Award ID(s):
- 2419923
- PAR ID:
- 10681658
- Publisher / Repository:
- Frontiers in Plant Science
- Date Published:
- Journal Name:
- Frontiers in Plant Science
- Volume:
- 16
- ISSN:
- 1664-462X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3389/fpls.2025.1585631
