Record ID No. |
4313 |
Author(s) |
Rodica Pena, Andrea Polle , 2014 |
Affiliation |
Forest Botany and Tree Physiology, Georg-August Universität Göttingen, Büsgenweg 2, Göttingen, Germany, E-mail: apolle@gwdg.de |
Title |
Attributing functions to ectomycorrhizal fungal identities in assemblages for nitrogen acquisition under stress |
Source. Vol.(no):Page |
ISME Journal 8(2): 321-330p. |
Categories |
Ectomycorrhiza |
Subjects |
Biochemistry |
Sub-subjects |
Nitrogen metabolism |
Host |
Plants |
Organism |
Ectomycorrhiza |
Country |
Germany, Western Europe |
Abstracts |
Mycorrhizal fungi have a key role in nitrogen (N) cycling, particularly in boreal and temperate ecosystems. However, the significance of ectomycorrhizal fungal (EMF) diversity for this important ecosystem function is unknown. Here, EMF taxon-specific N uptake was analyzed via 15 N isotope enrichment in complex root-associated assemblages and non-mycorrhizal root tips in controlled experiments. Specific 15 N enrichment in ectomycorrhizas, which represents the N influx and export, as well as the exchange of 15 N with the N pool of the root tip, was dependent on the fungal identity. Light or water deprivation revealed interspecific response diversity for N uptake. Partial taxon-specific N fluxes for ectomycorrhizas were assessed, and the benefits of EMF assemblages for plant N nutrition were estimated. We demonstrated that ectomycorrhizal assemblages provide advantages for inorganic N uptake compared with non-mycorrhizal roots under environmental constraints but not for unstressed plants. These benefits were realized via stress activation of distinct EMF taxa, which suggests significant functional diversity within EMF assemblages. We developed and validated a model that predicts net N flux into the plant based on taxon-specific 15 N enrichment in ectomycorrhizal root tips. These results open a new avenue to characterize the functional traits of EMF taxa in complex communities. |