An Evaluation of Several Media for Use in Identification of Some Fusarium Species

Carnation-leaf agar (CLA), low-nutrient agar (LNA) and dichloran-chloramphenicol-peptone agar (DCPA) were compared for their usefulness in the identification of Fusarium species in section Liseola and the species F. oxysporum, F. solani, F. nygamai, F. napiforme and F. beomiforme. Typical macroconidia, microconidia and chlamydospores were produced consistently on CLA which was the most suitable medium for Fusarium identification. The production of typical microconidia and chlamydospores was consistent on LNA, but sporodochia did not form and only a few macroconidia were produced in the aerial mycelium. On DCPA, formation of microconidia was not consistent, sporodochia were not formed, and only distorted macroconidia were formed in the aerial mycelium. Chlamydospores were slow to form and difficult to detect. This medium was not suitable for the reliable differentiation of the species examined. All isolates of F. oxysporum, F. solani, F. beomiforme, F. napiforme and F. nygamai produced chlamydospores after 2 weeks on soil agar (SA), a medium used solely to enhance chlamydospore formation. nt]mis|Contribution No. 1742, Fusarium Research Center, Department of Plant Pathology, The Pennsylvania State University Agricultural Experiment Station. Authorised for publication 4 May 1989 as Journal Series Paper No. 8174.