Abstract:
Zimbabwe embarked on planting Eucalyptus species in the early 1900’s. Based on a robust
breeding programme, it has become a major source of seed for other countries in and outside
Africa. Tree health surveys conducted on Eucalyptus in some east and southern Africa
countries over the past two decades have revealed several important fungal diseases that were
previously not known in the region, but little is known regarding these problems in
Zimbabwe. The aim of this study was to identify important eucalypt diseases across
Zimbabwe’s agro-climatic regions. Morphological characteristics and DNA sequence data
were used to identify pathogens collected to species level. Widespread stem canker diseases,
caused by species belonging to the Botryosphaeriaceae and Teratosphaeriaceae, and leaf spot
diseases caused by fungi in the Capnodiales, were identified. Armillaria root and stem rot was
restricted to a single site in the Eastern Highlands. Fungi that could cause canker or blue stain
of timber were isolated from recently harvested stumps and included species of Ceratocystis
and Ophiostoma. This study is the first to identify Eucalyptus pathogens to species level in
Zimbabwe and we report for the first time the presence of the stem canker pathogen T.gauchensis in southern Africa. The results will provide a foundation for the formulation of
future disease management strategies in the country.
