Phosphorus dependence in seedlings of a tropical pioneer tree: the role of arbuscular mycorrhizae

In general, according to previous studies, pioneer species do not require arbuscular mycorrhizal fungi (AMF) to increase their growth and survival in tropical systems. The aim of this study was to determine the dependence response to AMF of Heliocarpus appendiculatus, a pioneer species, at different...

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Detalhes bibliográficos
Autores: Guadarrama-Chávez, María Patricia, Álvarez-Sánchez, Francisco Javier, Estrada-Torres, A
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2004
País:México
Recursos:Universidad Nacional Autónoma de México
Repositório:Sistema de Información de la Facultad de Ciencias, UNAM
OAI Identifier:oai:repositorio.fciencias.unam.mx:11154/141189
Acesso em linha:http://hdl.handle.net/11154/141189
Access Level:Acceso aberto
Palavra-chave:Arbuscular mycorrhizae
Heliocarpus appendiculatus
Mycorrhizal dependency
Pioneer species
Tropical rain forest
Descrição
Resumo:In general, according to previous studies, pioneer species do not require arbuscular mycorrhizal fungi (AMF) to increase their growth and survival in tropical systems. The aim of this study was to determine the dependence response to AMF of Heliocarpus appendiculatus, a pioneer species, at different phosphorus (P) levels. In a greenhouse experiment, H. appendiculatus seedlings were grown in pots with a sterile vermiculite-sand mixture (1:1). Two sets of pots were set up: One set was inoculated (150 spores per pot) with indigenous AMF from a tropical rain forest at “Los Tuxtlas” (Veracruz, Mexico); the other set was not inoculated. To each set, 0, 0.02, 0.2, and 2 g L?1P was added. All pots were watered with 250 mL of nutrient solution. Mycorrhizal plants showed a higher total dry weight and relative growth rate in 0.02 g L?1P concentration, while nonmycorrhizal plants responded positively at 0.2 g L?1P; a decrease in plant responses at higher P levels was observed in both treatments. H. appendiculatus showed to have higher relative dependence at lower P concentration (?50%). As levels of P increased, mycorrhizal colonization decreased. Successful growth of pioneer species during succession process may be improved if there is AMF content in soils, prior to disturbance.