Shared compatibility of ectomycorrhizae on Pseudotsuga menziesii and Betula papyrifera seedlings grown in mixture in soils from southern British Columbia

Seedlings of Pseudotsuga menziesii (Mirb.) France and Betula papyrifera Marsh. were grown in the greenhouse in monoculture and dual culture in soils collected from a young mixed species plantation in the southern interior of British Columbia. The objectives of the study were (i) to evaluate the ability of P. menziesii and B. papyrifera to share compatible ectomycorrhizal fungi in order to assess their potential for hyphal linkages and (ii) to study the influence of neighboring seedlings on ectomycorrhizae occurrence. Eleven ectomycorrhizal morphotypes were recognized, seven of which P. menziesii and B. papyrifera seedlings shared in common over 90% of their root tips. The abundance and frequency of Rhizopogon, E-strain I, and Tuber on P. menziesii, and the frequency of Lactarius, Hebeloma, and Cenococcum on B. papyrifera, were affected by the presence of a neighboring seedling. The number of ectomycorrhizal morphotypes shared in common and colonization of root tips by common types were slightly greater when P. menziesii and B. papyrifera were grown in dual culture rather than in monoculture.