Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: June 2, 1998
Publication Date: N/A
Technical Abstract: Foliar diseases caused by fungal pathogens of maize and sorghum often appear very similar or are incited by species that are difficult to identify definitively. We investigated the use of species-specific nucleotide sequences of 5.8S rDNA/ITS regions for fungal identification. Common fungal pathogens of maize and sorghum were readily identified by the restriction fragments generated from separate digestions with Taq I and Mse I. The effectiveness of the method was demonstrated by distinguishing two taxonomically identical forms of Cercospora causing gray leaf spot of maize. Single lesions were extracted, and the rDNA/ITS was amplified directly by PCR with fungal specific primers and digested. In addition to facilitating studies of pathogen evolution and population structure, this approach allows rapid disease diagnosis without culturing the pathogen and without relying upon taxonomic criteria that are often unreliable or ambiguous.