SUSCEPTIBILITY OF BARLEY CULTIVARS TO VESICULAR-ARBUSCULAR MYCORRHIZAL FUNGI

The relative susceptibility of selected barley cultivars produced in w estern Canada to vesicular-arbuscular mycorrhizal (VAM) fungi under fi eld and greenhouse conditions was evaluated in this study. Cultivars t ested under field conditions at the University of Alberta and Lacombe research stations showed no significant differences in VAM colonizatio n of barley roots; colonization was light. Greenhouse trials at the Un iversity of Alberta with eight cultivars inoculated with individual my corrhizal species illustrated significant differences among the barley cultivars in their reactions to Glomus dimorphicum, G. intraradices, and G. mosseae. Distinct differences were observed in the ability of e ach Glomus species to colonize the barley cultivars. The VAM fungi inc reased growth and yield in some cultivars, depending on the Glomus spe cies. This study indicates that a degree of host-specificity exists in VAM fungi and that the host-mycorrhizal fungus genotypes may influenc e the effectiveness of the symbiosis.