Occurrence of Vesicular-Arbuscular Mycorrhizal Fungi in Alberta, Canada

S. M. Boyetchko* and J. P. Tewari Department of Plant Science, University of Alberta, Edmonton, Alberta, Canada T 6 G 2 P 5 Z. Naturforsch. 48c , 923-929 (1993); received April 6,1993 Vesicular-Arbuscular Mycorrhizae, Taxonomy, Calcium, X-Ray Microanalysis Three VA mycorrhizal fungal species were isolated from soils in Alberta, Canada and ex­ amined by scanning electron microscopy and energy-dispersive X-ray microanalysis. Mature spores of Glomus aggregatum developed an outer hyaline wall which contained lower levels of calcium than the middle wall. Examination of G. pansihalos spores revealed a lower level of calcium in the outer evanescent wall as compared to the ornamented wall. When spores of Entrophospora infrequens were examined, the wall of the vesicle was found to contain simi­ lar levels of calcium as the ornamented wall of the spore. The significance of the results con­ cerning the presence of calcium in mycorrhizal spore walls is discussed, as is the occurrence of the mycorrhizal species.