DETECTION OF GENETIC-VARIATION IN USTILAGO-MAYDIS STRAINS BY PROBES DERIVED FROM TELOMERIC SEQUENCES

Genetic variation using probes derived from telomeric sequences was an alysed among several Ustilago maydis strains in an attempt to identify discriminative fingerprint patterns. Three groups of wild isolates fr om different geographical areas and one group of standard laboratory s trains were examined. Analysis of the endmost restriction fragments (E Fs) and of the endmost-associated restriction fragments (EAFs) of the chromosomes revealed group differences. Most of the EFs in two groups of strains showed a similar length whereas in the other two groups the y were distributed in classes of different lengths. Furthermore, analy sis of the EAFs permitted possible fingerprint patterns to be predicte d for each group of strains based on the occurrence of amplified bands as well as the presence or absence of distinct bands which were shown to be present in terminal as well as in interstitial sites of the chr omosome. The approach evaluated in this work yielded highly polymorphi c fingerprint patterns and could be used to distinguish groups of fung al isolates; this approach may also be effective for other fungal syst ems.