Variability in the sorghum anthracnose fungus Colletotrichum graminicola in Brazil and USA.

Phenotypic diversity in the pathogen as detected for 10 random amplified polymorphic DNAs (RAPD) and for virulence on 8 differential cultivars was studied using monoconidial isolates (29 from 4 different areas of Brazil and 9 from Texas and Georgia in the USA). Virulence tests were carried out in the greenhouse using the genotypes TX378, SC326-6, SC283, TX623, Brandes, TX398, TX2536 and SC748-5. Greater diversity was found for RAPD markers than for virulence, indicating that this type of marker may be a useful tool in studying plant pathogen variability. There was no relation between geographical and phenotypic distance. Respectively 8 and 5 phenotypic clusters based on RAPD and virulence data were detected by cluster analysis..Proceedings of a Symposium International Agricultural Center in Wageningen, The Netherlands, 1992