THE GENUS LEPTOGRAPHIUM -- A RE-EVALUATION
K JACOBS1, MJ WINGFIELD1, PW CROUS 2 and BD WINGFIELD3
1Tree Pathology Co-operative Programme, Forestry and Agricultural Biotechnology Institute (FABI), Department of Microbiology and Plantpathology, University of Pretoria, Pretoria, 0002, Republic of South Africa; 2Department of Plant Pathology, University of Stellenbosch, Stellenbosch, 7602, Republic of South Africa; 3 Department of Genetics, University of Pretoria, Pretoria, 0002, Republic of South Africa
Background and objectives
Throughout its taxonomic history, the genus Leptographium has been associated with several different, but morphologically similar genera. The first of these, Scopularia, described in 1851, was synonymised with Leptographium in 1927 because the characters reported for the former genus could not be verified . Verticiciadieiia and Phialocephaia, two genera described in the Leptographium complex, were distinguished from Leptographium based on differences in conidium development. These differences were later shown not to be taxonomically reliable and Verticiciadieiia was reduced to synonymy with Leptographium. Those anamorphs of Ophiostoma, thought to represent Phialocephaia spp., have subsequently been accommodated in Leptographium . Species of Leptographium are morphologically similar and notoriously difficult to distinguish from one another. The lack of an effective key to species has contributed to difficulties in identifying these fungi. In many cases, the Ophiostoma state has been described with only a brief mention of the anamorph. In culture, the Leptographium state is predominant and a teleomorph is seldom found. Forest pathologists are commonly faced with the dilemma of having to identify Leptographium species based on poor descriptions and incomplete data. These problems have emphasised the need to re-evaluate Leptographium and to compile a comprehensive key to described species.
Materials and Methods
Results and conclusions