Author
Winton, Loretta | |
LEINER, ROSEANNE - UNIVERSITY OF ALASKA | |
Krohn, Andrew |
Submitted to: Phytopathology
Publication Type: Abstract Only Publication Acceptance Date: 5/18/2006 Publication Date: 7/20/2006 Citation: Winton, L.M., Leiner, R.H., Krohn, A.L. Hybridization and recombination in exotic and endemic Sclerotinia species in Alaska. Phytopathology 96:S124 Interpretive Summary: Technical Abstract: White mold is the major disease problem limiting vegetable production in Alaska. Initial diagnoses and isolations of the pathogen implicated Sclerotinia sclerotiorum. However, ribosomal DNA sequences and microsatellite markers revealed two sympatric Sclerotinia species involved in disease on various hosts. Fourteen multilocus genotypes of S. sclerotiorum, a cosmopolitan pathogen, were found as non-recombining clonal lineages on 54% of 219 diseased plants. Forty-six percent of diseased plants were colonized by Sclerotinia 'species 1', a putative endemic previously found on wild plants in Norway. Both species produced apothecia abundantly in the field but only those of 'species 1' provided evidence of outcrossing and produced sibling ascospores of different genotypes. Five hybrid isolates were identified that possess ribosomal sequences identical to 'species 1' and microsatellite profiles that characterize sclerotiorum. Genotypes of 'species 1', S. sclerotiorum, and hybrid isolates differ in growth rate and oxalic acid production in culture. |