Generic distinction in the Helminthosporium-complex based on restriction analysis of the nuclear ribosomal RNA gene

The DNA sequences coding for the nuclear 28S rRNA, 5.8S rRNA, and the internal transcribed spacers (ITS1 and ITS2) for 36 representative fungal species from Bipolaris, Cercospora, Corynespora, Curvularia, Drechslera, Exserohilum and Helminthosporium were amplified using the polymerase chain reaction. The amplified products were digested using restriction endonuclease Rsa I, and the electrophoretic patterns compared. With the exception of Bipolaris and Curvularia, cluster analysis of the restriction phenotypes clearly separated the genera. Bipolaris and Curvularia appeared to be more heterogeneous than the other allied genera within the Helminthosporium-complex.link_to_OA_fulltex