Record ID No. |
3504 |
Author(s) |
Corrêa, A., Gurevitch, J., Martins-Loução, M.A., Cruz, C. , 2012 |
Affiliation |
Depto de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, Profesor Albareda 1, ES-18008 Granada, Spain, E-mail: ambcorrea@gmail.com |
Title |
C allocation to the fungus is not a cost to the plant in ectomycorrhizae |
Source. Vol.(no):Page |
Oikos, 121 (3): 449-463p. |
Categories |
Ectomycorrhiza |
Subjects |
Biochemistry |
Host |
Plants |
Organism |
EcM., |
Country |
Spain, Europe |
Abstracts |
Mycorrhizal benefit to plants is most frequently evaluated through growth differences between mycorrhizal (M) and non-mycorrhizal (NM) plants. These growth differences are often considered to be due to differences in belowground C expenditure, or in cost efficiency, i.e. amount of nutrients acquired per C expended. We searched published reports for relations between plant growth and belowground C allocation, C use efficiency, or nutrient uptake, in ectomycorrhizal (ECM) versus non-mycorrhizal plants. We found a similar number of cases of negative, null or positive effects of ECM on plant growth. These effects were not correlated with differences on belowground C allocation or C use efficiency between M and NM plants. In contrast, they were very strongly correlated with mycorrhizal effects on plant N gain. A comprehensive analysis of the published data therefore provided evidence that C is an excess, rather than a costly, resource, and that the outcome of the symbiosis depends only on whether mycorrhizae result in increased or decreased nutrient acquisition compared with NM plants, and not on cost efficiency differences between M and NM plants. Consequences of this finding for the regulation of resource exchange between symbionts and the nature of the symbiosis are discussed. |