Fungal functional ecology: bringing a trait‐based approach to plant‐associated fungi

Abstract

Fungi play many essential roles in ecosystems. They facilitate plant access to nutrients and water, serve as decay agents that cycle carbon and nutrients through the soil, water and atmosphere, and are major regulators of macro‐organismal populations. Although technological advances are improving the detection and identification of fungi, there still exist key gaps in our ecological knowledge of this kingdom, especially related to function. Trait‐based approaches have been instrumental in strengthening our understanding of plant functional ecology and, as such, provide excellent models for deepening our understanding of fungal functional ecology in ways that complement insights gained from traditional and ‐omics‐based techniques. In this review, we synthesize current knowledge of fungal functional ecology, taxonomy and systematics and introduce a novel database of fungal functional traits (FunFun). FunFun is built to interface with other databases to explore and predict how fungal functional diversity varies by taxonomy, guild, and other evolutionary or ecological grouping variables. To highlight how a quantitative trait‐based approach can provide new insights, we describe multiple targeted examples and end by suggesting next steps in the rapidly growing field of fungal functional ecology.

Trait‐based aerial dispersal of arbuscular mycorrhizal fungi

“…Further research identifying variation in functional trait space and how it relates to ecological processes like dispersal will improve our understanding of mycorrhizal ecology (Zanne et al ., 2019). Unlike spore size, variation in melanization or spore ornamentation were not related to aerial AM fungal dispersal in our study and could not be compared broadly to all Glomeromycota due to a lack of available trait data for all described species.…”

“…Because the outcome of AM symbioses can vary as fungal communities shift, studying AM fungal dispersal in cities has implications for efforts to improve urban sustainability (Chaudhary et al ., 2019). We also compare the measured traits of aerial spores to known traits for all described AM fungi present in the FUN FUN fungal functional trait database (Zanne et al ., 2019). We predict that aerial AM fungal spores will possess traits more conducive to wind dispersal, such as a smaller diameter than the average for all AM fungal species (Hypothesis 1).…”

Species and intra-specific competition affect growth in greenhouse more than mycorrhizal colonization onQuercus rubraandAcer rubrumseedlings

“…Experimental results also underline this EM trait of organic N enzymatic processing (Bödeker et al, 2014) especially in those ectomycorrhiza descended from white rot as opposed to brown rot saprotrophic fungi (Stuart & Plett, 2020). Trait-based experimental design and analysis is increasingly recognized as a valuable method for characterizing guild differences (Lustenhouwer, Maynard, Bradford, Lindner, & Oberle, 2020;Mcgill, Enquist, Weiher, & Westoby, 2006;Zanne et al, 2020). Considering current projections of atmospheric CO2 increase, nitrogen deposition, phosphorus limitations, and the degradation and loss of forests worldwide (Crowther et al, 2016;Fitter, Heinemeyer, & Staddon, 2000;IPCC, 2014), clarifying the ecological function of mycorrhizal symbiosis is timely and relevant.…”

Explorative Meta-Analysis of 377 Extant Fungal Genomes Predicted a Total Mycobiome Functionality of 42.4 Million KEGG Functions

“…Here, we demonstrate that the difference in lifestyle between endophytic and ectomycorrhizal fungi could derive from functional diversity and genome content, respectively, despite both being associated with plants. Admittedly, the importance of the genome content of mycorrhizal fungi is questionable as the convergent evolution of the mycorrhizal habit occurred via the repeated evolution from saprotrophic ancestors (Kohler et al, 2015) but genomic sequencing revealed substantial variation between species from the same functional guild resulting in the analysis of trait-based approaches for understanding fungal activity instead of continuous classifications (Zanne et al, 2019). A trait-based approach to measure enzyme activity directly will be necessary when taxa do not fit into functional guilds (Peay et al, 2016).…”