INVESTIGADORES
SCHOLZ Fabian Gustavo
artículos
Título:
Freezing avoidance by supercooling in Olea europaea cultivars: the role of apoplastic water, solute content and cell wall rigidity
Autor/es:
ARIAS NS, BUCCI SJ, SCHOLZ FG, GOLDSTEIN G
Revista:
PLANT, CELL AND ENVIRONMENT (PRINT)
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2015
ISSN:
0140-7791
Resumen:
Plants can avoid
freezing damage by preventing extracellular ice formation below the equilibrium freezing temperature
(supercooling). We used Olea europaea cultivars to assess which traits
contribute to avoid ice nucleation at subzero temperatures. Seasonal leaf water relations, non-structural carbohydrates, nitrogen and tissue damage and ice nucleation temperatures in different plant parts were determined in
five cultivars growing in the patagonian
cold desert. Ice seeding in roots occurred at higher
temperatures than in stems and leaves. Leaves of cold acclimated cultivars supercooled down
to -13 ºC, substantially lower than the minimum air temperatures observed in
the study site. During winter, leaf ice nucleation and leaf freezing damage (LT50)
occurred at similar temperatures, typical of plant tissues that supercool. Higher
leaf density and cell wall rigidity were observed during winter, consistent
with a substantial acclimation to sub-zero temperatures. Larger supercooling
capacity and lower LT50 were observed in cold-acclimated cultivars
with higher osmotically active solute content, higher tissue elastic adjustments
and lower apoplastic water. Irreversible leaf damage was only observed in laboratory
experiments at very low temperatures, but not in the field. A comparative analysis
of closely related plants avoids phylogenetic independence bias in a
comparative study of adaptations to survive low temperatures.