Abstract:

Armillaria spp. can have a very wide host range including eucalypts, pine, apples, peaches, citrus, litchis and many indigenous forest tree species. This fungus is, therefore, economically important to a number of industries. Very little is known concerning the identity of Armillaria spp. in South Africa. The species A. heimii is believed to be present although this must be confirmed. Other species with defined host ranges might also be present. In forestry situations, Armillaria root rot has been recorded on both pines and eucalypts although there is some doubt as to whether the disease is serious in eucalypts. There is some evidence to suggest that where, eucalypts are planted in pine infection centres, the eucalypts will not be affected by this disease. This might imply that at least one of the species of Armillaria present, displays some level of host specificity. This aspect of the biology of Armillaria in South Africa deserves further consideration.