Artículo
Low-temperature resistance in Polylepis tarapacana, a tree growing at the highest altitudes in the world
Rada, Fermín; García Núñez, Carlos; Boero, Cecilia; Gallardo, Miriam Rosa Angela; Hilal, Mirna Beatriz; González, Juan Antonio; Prado, Fernando Eduardo
; Liberman Cruz, Máximo; Azócar, Aura
Fecha de publicación:
12/2001
Editorial:
Wiley Blackwell Publishing, Inc
Revista:
Plant, Cell and Environment
ISSN:
0140-7791
Idioma:
Inglés
Tipo de recurso:
Artículo publicado
Clasificación temática:
Resumen
The Polylepis tarapacana forests found in Bolivia are unique with respect to their altitudinal distribution (4200-5200 m). Given the extreme environmental conditions that characterize these altitudes, this species has to rely on distinct mechanisms to survive stressful temperatures. The purpose of this study was to determine low-temperature resistance mechanisms in P. tarapacana. Tissue was sampled for carbohydrate and praline contents and micro-climatic measurements were made at two altitudes, 4300 and 4850 m, during both the dry cold and wet warm seasons. Supercooling capacity (-3 to -6 °C for the cold dry and -7 to -9 °C for the wet warm season) and injury temperatures (-18 to -23 °C for both seasons), determined in the laboratory, indicate that P. tarapacana is a frost-tolerant species. On the other hand, an increase in supercooling capacity, as the result of significant increase in total soluble sugar and praline contents, occurs during the wet warm season as a consequence of higher metabolic activity. Hence, P. tarapacana, a frost-tolerant species during the colder unfavourable season, is able to avoid freezing during the more favourable season when minimum night-time temperatures are not as extreme.
Palabras clave:
Cold Resistance
,
Freezing Avoidance
,
Frost Tolerance
,
Tree Line
,
Tropical Andes
Archivos asociados
Licencia
Identificadores
Colecciones
Articulos(CCT - NOA SUR)
Articulos de CTRO.CIENTIFICO TECNOL.CONICET - NOA SUR
Articulos de CTRO.CIENTIFICO TECNOL.CONICET - NOA SUR
Citación
Rada, Fermín; García Núñez, Carlos; Boero, Cecilia; Gallardo, Miriam Rosa Angela; Hilal, Mirna Beatriz; et al.; Low-temperature resistance in Polylepis tarapacana, a tree growing at the highest altitudes in the world; Wiley Blackwell Publishing, Inc; Plant, Cell and Environment; 24; 3; 12-2001; 377-381
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