Bacterial community on ectomycorrhizal roots of Laccaria laccata in a chestnut plantation

This study investigated the bacterial communities present on the ectomycorrhizal roots of Laccaria laccata using culture- and cloning-based methods. One soil core was collected from five locations where sporocarps of L. laccata occurred in a chestnut plantation. A total of 10 and 50 ectomycorrhizal root tips of L. laccata were collected from each soil core and subjected to bacterial isolation and cloning. In total, 223 isolates were classified into 35 molecular operational taxonomic units (MOTUs). The majority of MOTUs were infrequent, whereas one MOTU each of Rhizobium and Bradyrhizobium were common across the sampling locations. In the cloning-based method, 77 MOTUs were detected. The majority of these MOTUs were infrequent, whereas one MOTU each of Bradyrhizobium and one taxon of Gammaproteobacteria was common across the sampling locations. These results indicate that Bradyrhizobium is a common member of bacteria present on the ectomycorrhizal roots of L. laccata in the chestnut plantation.