Anthracnose, caused by Colletotrichum sublineolum, has been one of the most destructive diseases affecting sorghum crops in Brazil. This study aimed to characterize wild and mutant strains through morphological and cultural characteristics, conidiation, and mating-type. A high variability was observed among strains when evaluated through radial growth and type of conidia produced. Spontaneous release of sectors by some strains was also observed, confirming the high genetic instability of this pathogen. Mating type genes amplified through PCRs using the primers, SKCM1, NcHMG and HGMgram demonstrated that both idiomorphs are present in this species. All the strains analyzed were self-sterile. It was not possible to correlate the auxotrophic mutant phenotype with the morphological characteristics evaluated.
