DOI: 10.5061/dryad.mkkwh712p
title: Intraspecific variation in mycorrhizal response is much larger than ecological literature suggests

description: Mycorrhizal response is the most common metric for characterizing how much
 benefit a plant derives from mycorrhizal symbiosis. Traditionally,
 ecologists have used these metrics to generalize benefit from mycorrhizal
 symbiosis in plant species, ignoring the potential for plant intraspecific
 trait variation to alter the outcome of the mutualism. In order for mean
 trait values to be useful as a functional trait to describe a species, as
 has been attempted for mycorrhizal response traits, interspecific
 variation must be much larger than intraspecific variation. While the
 variation among species has been extensively studied with respect to
 mycorrhizal response traits, variation within species has rarely been
 examined. We conducted a systematic review and analyzed how much variation
 for mycorrhizal growth and nutrient response typically exists within a
 plant species. We assessed 26 publications that included 56 individual
 studies testing mycorrhizal response in at least five genotypes of a plant
 species, and we found that intraspecific trait variation for mycorrhizal
 response was generally very large and highly variable depending on study
 design. The difference between the highest and lowest growth response in a
 study ranged from 10% to 350% across studies, and 37 of the studies
 included species for which both positive and negative growth responses to
 mycorrhizae were observed across different genotypes. Phosphorus
 concentration and content were measured in 15 studies and variation was
 similar to variation in growth responses. We also found that plant
 genotype was just as important for predicting mycorrhizal response as the
 effects of fungal inoculant identity. Our analysis highlights not only the
 potential importance of intraspecific trait variation for mycorrhizal
 response but also the lack of research that has been done on the scale of
 this variation in plant species. Including intraspecific variation in
 research on the interactions between plants and their symbionts can
 increase our understanding of plant coexistence and ecological stability.
description: See full text of the article for a description of data collection
 and analysis. A systematic review of published literature identified
 papers that studied mycorrhizal responses in more than five genotypes of
 the same species. The presented data were extracted from these sources and
 used to document variation in mycorrhizal growth response and mycorrhizal
 phosphorus response within plant species. These data were also used in a
 meta-analysis of correlations between growth and phosphorus response, as
 well as to determine the relative importance of plant genotype when
 compared to mycorrhizal isolate/species and phosphorus
 treatments.
description: Data is presented in two forms: raw data (plant biomass,
 phosphorus concentration, and phosphorus content) from each study in
 individual CSV files, and processed data (mycorrhizal growth response,
 mycorrhizal phosphorus response) that includes all studies used in a given
 analysis. The Web of Science search results from the keywords provided in
 the full text of the associated article are also provided.