Ultrastructural damage in coffee seeds exposed to drying and to subzero (°C) temperatures



During drying and freezing, protective mechanisms act to maintain seed physiological quality. Some of these mechanisms contribute to the integrity of cell membranes. The damage caused to cell membranes due to cell stress can be seen in ultrastructural studies. The aim of this study was to investigate ultrastructural changes in endosperm cells of coffee seeds brought about by drying and by exposure to low temperatures. Seeds of Coffea arabica  were dried in silica gel to moisture contents of 40, 20, and 5 % (wb) and brought to equilibrium at temperatures of 10, -20, and -86oC. Germination, vigor, and tetrazolium tests were performed for evaluation of seed physiological quality. Ultrastructural damage was analyzed by scanning electron microscopy. Coffee seeds with 40% moisture content have whole, swollen, and expanded cells, with a filled lumen and without signs of damage. The physiological and ultrastructural quality of seeds exposed to below zero temperatures with 40% moisture content is compromised. They have null germination and empty cells, indicating leakage of cell content. Drying of coffee seeds leads to uniform contraction of inner cell content. Drying of coffee seeds to 5% moisture content leads to intense contraction of cell volume, with physiological and ultrastructural damage.

Key words: Scanning electron microscopy; desiccation tolerance; Coffea arabica L.


BERJAK, P.; PAMMENTER, N. W. Implications of the lack of desiccation tolerance in recalcitrant seeds. Frontiers in plant science, 22(4):1-9, 2013.

BHANDARI, K.; NAYYAR, H. Low temperature stress in plants: An overview of roles of cryoprotectants in defense. In: AHMAD, P.; WANI, M. (Eds.). Physiological Mechanisms and Adaptation Strategies in Plants Under Changing Environment. Springer, New York, NY, p.193-265, 2014.

BLACK, M.; PRITCHARD, H. W. Glossary. In: BLACK, M.; PRITCHARD, H. W. (Ed). Desiccation and survival in plants: Drying without dying. New York: CAB International, p.373-382, 2002.

BORÉM, F. M. et al. Qualidade do café submetido a diferentes temperaturas, fluxos de ar e períodos de présecagem. Coffee Science, 1(1):55-63, 2006.

BRASIL. Ministério da Agricultura, Pecuária e Abastecimento. Secretaria de Defesa Agropecuária. Regras para análise de sementes. Brasília, DF: MAPA: SDA, 2009. 395p.

CLEMENTE, A. C. S. et al. Preparo das sementes de café para a avaliação da viabilidade pelo teste de tetrazólio. Revista Brasileira de Sementes, 33(1):38-44, 2011.

COELHO, S. V. B.; ROSA, S. D. V. F.; FERNANDES, J. S. Cryopreservation of coffee seeds: A simplified method. Seed Science and Technology, 45(3):638-649, 2017.

DUSSERT, S. et al. Biologie de la conservation des semences de caféiers: Aspects fondamentaux et conséquences pratiques: une revue. Cahiers Agricultures, 21(2-3):106-114, 2012.

ELLIS, R. H.; HONG, T. D.; ROBERTS, E. H. Na intermediate category of seed storage behaviour?: I. Coffee. Journal of Experimental Botany, 41(9):1167-1174, 1990.

FARIA, J. M. et al. Changes in DNA and microtubules during loss and re-establishment of desiccation tolerance in germinating Medicago truncatula seeds. Journal of Experimental Botany, 56(418):2119-2130, 2005.

FERREIRA, D. F. Sisvar: A guide for its bootstrap procedures in multiple comparisons. Ciência e Agrotecnologia, 38(2):109-112, 2014.

FIGUEIREDO, M. A. et al. Exploratory studies for cryopreservation of Coffea arabica L. seeds. Journal of Seed Science, 39(2):150-158, 2017.

JONES, L.; MCQUEEN-MASON, S. A role for expansins in dehydration and rehydration of the resurrection plant Craterostigma plantagineum. FEBS Letters, 559(1-3):61-65, 2004.

JOSÉ, A. C. et al. Effects of drying rate and storage time on Magnolia ovate Spreng. seed viability. Seed Science and Technology, 39(2):425‑434, 2011.

MARCOS-FILHO, J. Fisiologia de sementes de plantas cultivadas. 2. ed., Londrina: ABRATES, 2015. 660p.

MOORE, J. P.; FARRANT, J. M.; DRIOUICH, A. A role for pectin-associated arabinans in maintaining the flexibility of the plant cell wall during water deficit stress. Plant Signaling & Behavior, 3(2):102-104, 2008.

PAMMENTER, N. W.; BERJAK, P. Physiology of desiccation-sensitive (recalcitrant) seeds and the implications for cryopreservation. International Journal

Plant Science, 175(1):21-28, 2014.

SAATH, R. et al. Microscopia eletrônica de varredura do endosperma de café (Coffea arabica L.) durante o processo de secagem. Ciência e Agrotecnologia, 34(1):196-203, 2010.

SANTOS, M. A.; CHALFOUN, S. M.; PIMENTA, C. J. Influência do processamento por via úmida e tipos de secagem sobre a composição, físico-química e química do café (Coffea arabica L.). Ciência e Agrotecnologia, 33(1):213-218, 2009.

SHIGA, T. M.; LAJOLO, F. M. Cell wall polysaccharides of common beans (Phaseolus vulgaris L.): composition and structure. Carbohydrate Polymers, 3(1):1-12, 2006.

SILVA, P. A. et al. Análise fisiológica e ultra-estrutural durante o desenvolvimento e a secagem de sementes de soja. Revista Brasileira de Sementes, 29(2):15-22,

UMARANI, R.; AADHAVAN, E. K.; FAISAL, M. M. Understanding poor storage potential of recalcitrant seeds. Current Science, 108(11):2023-2034, 2015.

VICRÉ, M.; FARRANT, J. M.; DRIOUICH, A. Insights into the cellular mechanisms of desiccation tolerance among angiosperm resurrection plant species. Plant, Cell & Environment, 27(11):1365-3040, 2004.

WALTERS, C. Orthodoxy, recalcitrance and in-between: Describing variation in seed storage characteristics using threshold responses to water loss. Planta, 242(2):397-406, 2015.

WESLEY-SMITH, J. et al. Why is intracellular ice lethal? A microscopical study showing evidence of programmed cell death in cryo-exposed embryonic axes of recalcitrante seeds of Acer saccharinum. Annals of Botany,115(6):991-1000, 2015.

WESLEY-SMITH, J. et al. Intracellular ice and cell survival in cryo-exposed embryonic axes of recalcitrant seeds of Acer saccharinum: An ultrastructural study of factors affecting cell and ice structures. Annals of Botany, 113(4):695-709, 2014.



How to Cite

COELHO, S. V. B.; ROSA, S. D. V. F. DA; LACERDA, L. N. C. .; CLEMENTE, A. DA C. S.; SILVA, L. C.; FANTAZZINI, T. B.; RIBEIRO, F. S. .; DE MELO CASTRO, E. . Ultrastructural damage in coffee seeds exposed to drying and to subzero (°C) temperatures. Coffee Science - ISSN 1984-3909, v. 15, p. e151760, 11 Aug. 2020.