Abstract

Mohmed S. Khalil, Mohmed A. Abdel-Sattar, Ibrahim N. Aly, Kamel A. Abd-Elsalam and Joseph A. Verreet

Random amplified polymorphic DNA (RAPD) analyses was used in combination with pathogenicity assays to study the taxonomic kinships among five Fusarium species. A total of 46 isolates of Fusarium spp. obtained from diseased cotton seedlings showing typical root rot and dampping-off symptoms were characterized. Of 10 primers tested, four primers produced polymorphic amplification patterns with taxon-specific bands, in addition to individual- specific bands. Genetic analysis indicated into 2 main clusters, with the minor cluster included all F. moniliforme and F. solani at the genetic similarity of GS=57.82%. The major cluster consisted of all F. oxysporum, F. avenaceum and F. chlamydosporum clustered at 71% similarity. There was no clear-cut relationship between clustering in the RAPD dendrogram, pathogenicity test and geographic origin of tested isolates. The results suggest that RAPD-PCR is a useful method for analysing genetic variation within and between Fusarium spp.