Mycorrhizal inoculation of Pinus ponderosa in Patagonia, Argentina: rootlets colonization, morphotypes descriptions and seedling growth in nursery

Abstract

Selection of ectomycorrhizal species to inoculate seedlings of exotic Pinaceae is a necessary step to ensure establishment, survival and growth in the forests. The use of spores as inoculum source has proven to be efficient, accessible and low-cost. In this paper we pursued the following objectives: a) to evaluate the effectiveness of inoculation with spores of Rhizopogon roseolus, Suillus luteus Hebeloma mesophaeum and Tricholoma muricatum on Pinus ponderosa seedlings, b) to determine the effect of mycorrhization on the morphometry of seedlings at planting time and c) to describe the mycorrhizal morphotypes of each individual association. We verified the success of mycorrhization with spores of S. luteus, R. roseolus and H. mesophaeum; the first two present the highest values of colonization, thus validating this technique of inoculation as successful for these species. Inoculation with T. muricatum was not successful, which excludes this species as a possible source of inoculum. The morphology of morphotypes developed by S. luteus and R. roseolus was constant, though very variable in H. mesophaeum. Morphometric parameters of inoculated seedlings did not differ from those of non-inoculated control, corroborating results from other parts of the world.