MOLECULAR PHYLOGENY AND EVOLUTION OF MONILINIA (SCLEROTINIACEAE) BASED ON CODING AND NONCODING RDNA SEQUENCES

The nuclear internal transcribed spacers, the 5.8S subunit, approximat e to 560 bp of the small subunit, and approximate to 320 bp of the lar ge subunit of the nuclear ribosomal DNA repeat from 17 species of Moni linia and eight species of closely related genera were sequenced. Phyl ogenies were constructed using maximum parsimony. The results support the hypothesis that Monilinia is not monophyletic. A fundamental disti nction was found between the section Junctoriae and the section Disjun ctoriae. Four evolutionary lineages were identified within the Disjunc toriae: one species on Crataegus, one group of species on dry stone fr uits of rosaceous hosts, one group of species on capsular fruits of er icaceous hosts, and one group of species on sweet berry fruits of eric aceous hosts. Comparisons between branching topologies of hosts and Mo nilinia species suggest that although cospeciation among hosts and par asites has been the rule, several host jumps have taken place. Sclerot inia pirolae was determined to be a true member of the Disjunctoriae. The closest taxon groups to the Junctoriae were found to be Botrytis a nd Sclerotinia, with Ciborinia being the closest taxon group to the Di sjunctoriae. There is evidence of an increased rate of ssrRNA evolutio n in the lineage of species that attack ericaceous berries.