Tipo
Artigos em Revista
Tipo de Documento
Artigo Completo
Título
Testing the trade‐balance model: resource stoichiometry does not sufficiently explain AM effects
Participantes na publicação
A Corrêa (Author)
N Ferrol (Author)
C Cruz (Author)
Dep. Biologia Vegetal
CE3C
Resumo
\\n Variations in arbuscular mycorrhizae (AM) effects on plant growth (MGR) are commonly assumed to result from cost : benefit balances, with C as the cost and, most frequently, P as the benefit. The trade-balance model (TBM) adopts these assumptions and hypothesizes that mycorrhizal benefit depends on C : N : P stoichiometry. Although widely accepted, the TBM has not been experimentally tested.\\n We isolated the parameters included in the TBM and tested these assumptions using it as framework. Oryza sativa plants were supplied with different N : P ratios at low light level, establishing different C : P and C : N exchange rates, and C, N or P limitation. MGR and effects on nutrient uptake, %M, ERM, photosynthesis and shoot starch were measured.\\n C distribution to AM fungi played no role in MGR, and N was essential for all AM effects, including on P nutrition. C distribution to AM and MGR varied with the limiting nutrient (N or P), and evidence of extensive interplay between N and P was observed.\\n The TBM was not confirmed. The results agreed with the exchange of surplus resources and source–sink regulation of resource distribution among plants and AMF. Rather than depending on exchange rates, resource exchange may simply obey both symbiont needs, not requiring further regulation.\\n
Data de Publicação
2023-11-27
Instituição
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Suporte
New Phytologist
Identificadores da Publicação