Identification of Kenyan Armillaria isolates by cultural morphology,intersterility tests and analysis of isozyme profiles

Three groups of morphologically distinct isolates were observed among nine Kenyan Armillaria isolates based on their mycelium and rhizomorphs characteristics. Seven of the isolates were interfertile with testers of North American biological species III, VII and IX. However, tests with benomyl segregants BEN 433, BEN 157-10 and BEN AVK were intersterile with the same testers and also with the European A. mellea, A. lutea and A. ostoyae. The analysis of isozyme profiles showed that morphologically similar isolates had similar isozyme profiles of esterases. Their profiles however differed from those of the European A. mellea, A. lutea and A. ostoyae. On the basis of intersterility tests and analysis of isozyme profiles, the Kenyan isolates should be considered different.