To identify Stagonospora avenae genetically, 53 isolates
from Europe and North America were assessed by RFLP analysis and internal
transcribed spacer (ITS) sequence polymorphisms in comparison with isolates
of
S. nodorum, S. arenaria and Septoria tritici.
Our results
also provided insight on possible phylogenetic divergence within the species
currently identified by characteristic conidial morphology
as S. avenae. Isolates from Europe, Canada, Minnesota and North
Dakota
showed little genetic variation. In RFLP and ITS sequence
analyses, S. avenae isolates from New York and ATCC 12277 (origin
unknown) had a closer relationship with barley-biotype
S. nodorum, and S. avenae f. sp. triticea isolates
of ATCC 26370 and ATCC 26377 from Minnesota were closely associated with
wheat-biotype S. nodorum. Enzyme restrictions of ITS PCR-amplified
products
could facilitate the identification of Stagonospora on cereals.