Morphological and physiological responses of beech (Fagus sylvatica) seedlings to grass-induced belowground competition

We examined morphological and physiological responses of beech (Fagus sylvatica L.) seedlings to grass-induced belowground competition in full-light conditions. Two-year-old beech seedlings were grown during two growing seasons in 160-l containers in bare soil or with a mixture of five grass species...

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Detalles Bibliográficos
Autores: Coll Mir, Lluís, Balandier, Philippe, Picon-Cochard, Catherine
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2004
País:España
Institución:Universitat de Lleida (UdL)
Repositorio:Repositori Obert UdL
OAI Identifier:oai:repositori.udl.cat:10459.1/68271
Acceso en línea:https://doi.org/10.1093/treephys/24.1.45
http://hdl.handle.net/10459.1/68271
Access Level:acceso abierto
Palabra clave:Leaf gas exchange
Seedling architecture
Soil water content
Descripción
Sumario:We examined morphological and physiological responses of beech (Fagus sylvatica L.) seedlings to grass-induced belowground competition in full-light conditions. Two-year-old beech seedlings were grown during two growing seasons in 160-l containers in bare soil or with a mixture of five grass species widely represented in semi-natural meadows of central France. At the end of the second growing season, beech seedlings in the presence of grass showed significant reductions in diameter and height growth, annual shoot elongation, and stem, root and leaf biomass, but an increase in root to shoot biomass ratio. Grasses greatly reduced soil water availability, which was positively correlated with daily seedling diameter increment. Beech seedlings seemed to respond to water deficit by anticipating stomatal closure. There was evidence of competition for nitrogen (N) by grasses, but its effect on seedling development could not be separated from that of competition for water. By labeling the plants with 15N, we showed that beech seedlings absorbed little N when grasses were present, whereas grasses took up more than 97% of the total N absorbed in the container. We conclude that, even if beech seedlings display morphological and physiological adaptation to belowground competition, their development in full-light conditions may be strongly restricted by competition from grass species.