Genetic variation in Drechslera teres populations as indicated by RAPD markers

Random amplified polymorphic DNA (RAPD) was used to assess genetic variation among 48 isolates of Drechslera teres originating from different sites in Finland. RAPD profiles were generated with five arbitrary 10-mer primers and revealed polymorphisms suitable for screening differentiation in this fungal population. Using UPGMA clustering analysis, a similarity coefficient of approximately 63% was observed between all D. teres isolates studied. The variation was, however, distributed on a small scale as different genotypes were found from the same plant. The isolates could not be grouped according to geographic origin, aggressiveness, growth rate or morphological features, indicating that the primers used in this study were neutral markers for these characters. The primers were, however, able to differentiate between isolates of Helminthosporium species (D. teres, Drechslera graminea and Bipolaris sorokiniana).