Seed dormancy responses to temperature relate to Nothofagus species distribution and determine temporal patterns of germination across altitudes in Patagonia

Seeds integrate environmental cues that modulate their dormancy and germination. Although many mechanisms have been identified in laboratory experiments, their contribution to germination dynamics in existing communities and their involvement in defining species habitats remain elusive. By coupling...

Descripción completa

Detalles Bibliográficos
Autores: Arana, María Verónica, Gonzalez Polo, Marina, Martinez Meier, Alejandro, Gallo, Leonardo Ariel, Benech-Arnold, Roberto Luis, Sanchez, Rodolfo Augusto, Batlla, Diego
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Instituto Nacional de Tecnología Agropecuaria
Repositorio:INTA Digital (INTA)
Idioma:inglés
OAI Identifier:oai:localhost:20.500.12123/1301
Acceso en línea:http://hdl.handle.net/20.500.12123/1301
http://onlinelibrary.wiley.com/doi/10.1111/nph.13606/full
Access Level:acceso abierto
Palabra clave:Nothofagus
Dormición
Temperatura
Semillas
Germinación de las Semillas
Dormancy
Temperature
Seed
Seed Germination
Región Patagónica
Descripción
Sumario:Seeds integrate environmental cues that modulate their dormancy and germination. Although many mechanisms have been identified in laboratory experiments, their contribution to germination dynamics in existing communities and their involvement in defining species habitats remain elusive. By coupling mathematical models with ecological data we investigated the contribution of seed temperature responses to the dynamics of germination of three Nothofagus species that are sharply distributed across different altitudes in the Patagonian Andes. Seed responsiveness to temperature of the three Nothofagus species was linked to the thermal characteristics of their preferred ecological niche. In their natural distribution range, there was overlap in the timing of germination of the species, which was restricted to mid-spring. By contrast, outside their species distribution range, germination was temporally uncoupled with altitude. This phenomenon was described mathematically by the interplay between interspecific differences in seed population thermal parameters and the range in soil thermic environments across different altitudes. The observed interspecific variations in seed responsiveness to temperature and its environmental regulation, constitute a major determinant of the dynamics of Nothofagus germination across elevations. This phenomenon likely contributes to the maintenance of patterns of species abundance across altitude by placing germinated seeds in a favorable environment for plant growth.