HOST RANGE AND GEOGRAPHIC-DISTRIBUTION OF ARMILLARIA ROOT-ROT PATHOGENS IN THE CANADIAN PRAIRIE PROVINCES

A survey to identify Armillaria root rot pathogens, their host range, and geographic distribution was conducted in the Canadian prairie provinces. Collections of basidiocarps and isolates from the wood of symptomatic or dead trees were made. Armillaria species were identified by interfertility testing and by the L-DOPA method. Three Armillaria species, A. ostoyae (Romagn.) Herink, A. sinapina Berube & Dessureault, and A. calvescens Berube & Dessureault, were identified. Armillaria ostoyae was the most common species in both the subalpine and boreal forests and was found on a wide variety of coniferous and deciduous host species. Armillaria sinapina was in both the boreal and subalpine forests but occurred primarily on deciduous host species. Armillaria calvescens was rare and was found only in the boreal forest on both coniferous and deciduous host species.