A Protective Role for Accumulated Dry Matter Reserves in Seeds During Desiccation: Implications for Conservation

  • Hector PérezEmail author
  • Lisa M. Hill
  • Christina Walters


We live in an unprecedented time of plant biodiversity loss. Current extinction rates are three orders of magnitude faster than extinction rates measured over geologic time. Similarly, 30% of plants are threatened with extinction. This information is startling when one considers that humans depend on plants for life. Fortunately, several systems exist to conserve plant genetic diversity. Seed storage within genebanks represents the most widely utilized system for plant conservation. One advantage of genebanking is that seed viability can be maintained for decades to centuries. Seeds must tolerate extensive post-harvest drying (5–10% moisture content) and cold (−18 °C) to maintain shelf-life for these periods. However, many important tropical seeds cannot tolerate drying to these levels thus precluding genebank storage. But what separates desiccation-tolerant from sensitive seeds? Previous hypotheses related to protective roles for certain sugars and proteins or the formation of intracellular glasses are insufficient. For instance, desiccation-tolerant and desiccation-sensitive seeds accumulate the same types and levels of protective molecules. Likewise, desiccation-sensitive seeds form intracellular glasses if dried sufficiently. Alternatively, using seeds of a tropical palm as a model, our work identifies a critical minimum level of cellular dry matter accumulation for appropriate desiccation tolerance. Our model suggests that cells must acquire >35% dry matter reserves to avoid lethal desiccation stress prior to genebanking. This level of dry matter accumulation may serve as a reference point for future breeding efforts or manipulation of the seed developmental program to enhance desiccation tolerance.


Conservation Dry matter Seed desiccation Genebank 



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  1. Berjak, P., & Pammenter, N. W. (2008). From Avicennia to Zizania: Seed recalcitrance in perspective. Annals of Botany, 101, 213–228.CrossRefGoogle Scholar
  2. Bewley, J. D., Bradford, K., Hilhorst, H., & Nongaki, H. (2012). Seeds: Physiology of development, germination and dormancy (p. 408). New York: Springer.Google Scholar
  3. Dickie, J. B., & Pritchard, H. W. (2002). Systematic and evolutionary aspects of desiccation tolerance in seeds. In Desiccation and survival in plants: Drying without dying (pp. 239–260). Wallingford: CAB International.CrossRefGoogle Scholar
  4. FAO. (2014). Genebank standards for plant genetic resources for food and agriculture (p. 182). Rome: Food and Agriculture Organization of the United Nations.Google Scholar
  5. Frankel, O. H., Brown, A. H. D., & Burdon, J. J. (1995). The conservation of plant biodiversity (p. 299). Cambridge, UK: Cambridge University Press.Google Scholar
  6. Kermode, A. R., & Finch-Savage, W. E. (2002). Desiccation sensitivity in orthodox and recalcitrant seeds in relation to development. In M. Black & H. W. Pritchard (Eds.), Desiccation and survival in plants: Drying without dying (pp. 149–184). Wallingford: CAB International.CrossRefGoogle Scholar
  7. Merryman, H. T. (1974). Freezing injury and its prevention in living cells. Annual Review of Biophysics and Bioengineering, 3, 341–363.CrossRefGoogle Scholar
  8. Pérez, H. E., Criley, R. A., & Baskin, C. C. (2008). Promoting germination in dormant seeds of Pritchardia remota (Kuntze) Beck., and endangered palm endemic to Hawaii. Natural Areas Journal, 28, 251–260.CrossRefGoogle Scholar
  9. Pérez, H. E., Hill, L. M., & Walters, C. (2012). An analysis of embryo development in palm: Interactions between dry matter accumulation and water relations in Pritchardia remota (Arecaceae). Seed Science Research, 22, 97–111.CrossRefGoogle Scholar
  10. Pimm, S. L., Jenkins, C. N., Abell, R., Brooks, T. M., Gittleman, J. L., Joppa, L. N., Raven, P. H., Roberts, C. M., & Sexton, J. O. (2014). The biodiversity of species and their rates of extinction, distribution, and protection. Science, 344, 1–10.CrossRefGoogle Scholar
  11. Steponkus, P. L., Uemura, M., & Webb, M. S. (1995). Freeze-induced destabilization of cellular membranes and lipid bilayers. In E. A. Disalvo & S. A. Simon (Eds.), Permeability and stability of lipid bilayers (pp. 77–104). Boca Raton: CRC Press.Google Scholar
  12. Vertucci, C. W., & Farrant, J. M. (1995). Acquisition and loss of desiccation tolerance. In J. Kigel & G. Galili (Eds.), Seed development and germination (pp. 237–272). New York: Marcel Dekker Inc.Google Scholar
  13. Walters, C. (1998). Understanding the mechanisms and kinetics of seed aging. Seed Science Research, 8, 223–244.CrossRefGoogle Scholar
  14. Walters, C., Hill, L. M., & Wheeler, L. J. (2005). Dying while dry: Kinetics and mechanisms of deterioration in desiccated organisms. Integrative and Comparative Biology, 45, 751–758.CrossRefGoogle Scholar
  15. Walters, C., Ballesteros, D., & Vertucci, V. A. (2010). Structural mechanics of seed deterioration: Standing the test of time. Plant Science, 179, 565–573.CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Hector Pérez
    • 1
    Email author
  • Lisa M. Hill
    • 2
  • Christina Walters
    • 2
  1. 1.Department of Environmental HorticultureUniversity of FloridaGainesvilleUSA
  2. 2.United States Department of Agriculture – Agricultural Research Service, National Lab for Genetic Resources PreservationFt. CollinsUSA

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