The Mycorrhizal Status of Plants at Alexandra Fiord, Ellesmere Island, Canada, a High Arctic Site

ABSTRACT

On the eastern coast of central Ellesmere Island, adjacent to Alexandra Fiord (78°53′N, 75°55′W) is a lowland arctic oasis with relatively lush and diverse vegetation compared to the polar desert and ice fields that cover most of the surrounding area. Twenty-four species of plants were sampled at this site and their roots examined for fungal colonization. Although 19 species showed some irregular, interor intracellular colonization by rhizosphere fungi or endophytes, only 11 species could, by the morphology and extent of the fungal colonization, be classified as mycorrhizal. Dark-walled, septate endophytes and Cenococcum-type mycorrhizal infections were not observed in our samples. Colonization classified as ectomycorrhizal was observed in Salix arctica, Dryas integrifolia, Pedicularis capitata, Saxifraga oppositifolia, Cassiope tetragona, and Kobresia myosuroides. Colonization classified as ericoid mycorrhizal was observed in Vaccinium uliginosum, Cassiope tetragona, and possibly in Carex nardina and Silene acaulis. Arbutoid mycorrhizae were observed in Pyrola grandiflora. Endomycorrhizae, with non-septate hyphae and arbuscles, but no vesicles, were observed in only one species, Dryopteris fragrans. The paucity of VA-mycorrhizal colonization in herbaceous species was notable at this site, especially when compared to reports for the same species from other arctic and alpine sites.

Key Words:

• Mycorrhizae
• arctic plants
• Ellesmere Island