Sixteen isolates of Claviceps spp. were analyzed for the production of polysaccharides, oligosaccharides, and sucrose metabolism under conditions of submerged fermentation. Physiological markers calculated by the Verhulst-Pearl law were used for hierarchical cluster analysis. Low correlation was found between physiologically based dendrogram and phylogenetic analysis constructed from an alignment of rDNA sequences. To confirm the intraspecific uniformity of physiological markers three isolates of C. africana from different hosts and locations were included. The influence of genotype, physiological variability, environmental location and habitat on metabolite production is discussed.