-Twenty-six isolates obtained from soybean crops (Glycine max) with typical anthracnose symptoms were identified as Colletotrichum truncatum (73 %) and C. destructivum (26 %). Their genetic relationships were studied using the AFLP method. A UPGMA phenogram divided the strains into two clusters corresponding with the two species. Genetic distances based on association coefficient were 0.71-0.89 among the 18 C. truncatum strains and 0.67-1 among the eight C. destructivum strains. Genetic variability within species, measured in terms of percentage of polymorphic loci, was high (<90%). Only two isolates showed 100% similarity, suggesting high intraspecific variability.

AFLP methodology was applied to characterize three Coprotus species (C. lacteus, C. niveus, C. sexdecimsporus) so as to estimate the levels of polymorphism within species, to analyze the phenetic relationships among them, and to contrast the AFLP findings to those of a previous RAPD study. The high number of AFLP bands obtained with the six assayed primers allowed us to detect intra-specific variability. The genetic variability within species obtained using AFLP (measured in terms of percentage of polymorphic loci) was two to three times higher than those obtained by RAPD. The phenograms generated by AFLP markers grouped all strains of the same species into three defined clusters, and a higher association between C. lacteus and C. sexdecimsporus was also observed. The AFLP technique could become a powerful tool for genera such as Coprotus, in which a high intra-specific homogeneity does not allow detection of genetic variability using other PCR-based markers.

Amplified restriction fragment length polymorphisms (AFLP) were used to assess the genetic diversity among species and isolates of the genus Saccobolus. Monosporic strains of five Saccobolus species were used throughout. The dendrogram obtained from the analysis of grouping (UPGMA) showed four groups of species. The ordination of isolates through the principal coordinates method exhibited nearly the same relations between isolates as the phenogram. Analysis of six samples identified as Saccobolus versicolor using morphological characters indicated the same diagnostic fingerprints as S. verrucisporus with the primer combinations tested. The isolates identified as S. versicolor may represent an intraspecific variant of S. verrucisporus. The results support the use of AFLP markers to delimit Saccobolus species. This methodology constitutes an additional tool to study the taxonomy of the genus, which has previously used only morphological characters.