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Many ectomycorrhizal fungi (EMF) are generalists, but most plant genera that form ectomycorrhizas have at least some fungal partners that are specific to that host genus. Because shared mycorrhizal fungi mediate plant community interactions, host preference has implications for plant succession and competition. We studied the EMF of oaks ( Quercus spp.) and pines ( Pinus spp.) in a forest in northern Florida, USA, focusing on symbionts shared with longleaf pine ( Pinus palustris Mill.). Longleaf pine is an important species in the southeastern USA, both for timber plantations and for restoring savanna and woodland habitat. However, we found no research on the composition of naturally occurring EMF on longleaf pine roots. A lower proportion of EMF operational taxonomic units (OTUs) were found colonizing both oaks and pines than expected, providing evidence of host preference within the community. Although most EMF were detected only on either oaks or pines, the OTUs found on both tended to be frequently occurring and abundant. Cenococcum OTUs were found to be significantly associated with oaks, an unexpected finding as this genus is widespread, with a broad host range. These results suggest that host preference of EMF may structure EMF communities and therefore influence ecosystem effects of mycorrhizal networks. [ABSTRACT FROM AUTHOR]

Common ecological restoration treatments such as thinning trees and prescribed burning could result in changes to soil fungal communities and changes to the function of those communities. Ectomycorrhizal fungi are especially likely to be affected as they are symbionts on plant roots and exhibit host and niche preferences. Ectomycorrhizal fungi also produce extracellular enzymes that are important in soil nutrient cycling. We conducted a community survey of ectomycorrhizal fungi and assayed ectomycorrhizal root tip enzyme activity using substrate plugs in northern Mississippi upland oak–pine woodland plots differing in restoration history to explore the influence of woodland restoration on ectomycorrhizal fungal community composition and function. Restoration treatment was significant in explaining the occurrence of the most common fungal species (Russula xerampelina) and the most common family (Thelephoraceae) in the ectomycorrhizal fungal community survey. Highest potential laccase, peroxidase, and N‐acetyl‐β‐d‐glucosaminidase enzyme activity were found in a prescribed burn plot, and the lowest enzyme activities at a wildfire plot, where richness of ectomycorrhizal fungi was also lower. Different fungal families displayed significantly different enzymatic capabilities, with Hydnangiaceae having the highest laccase activity and Tuberaceae having significantly higher peroxidase and chitinase activity than several other families. These results suggest that restoration treatments can affect ectomycorrhizal fungal community composition and function, and better understanding these changes can aid understanding of the niches of ectomycorrhizal fungi and the impacts of restoration. [ABSTRACT FROM AUTHOR]