Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme II: SYSTEMATICS, PHYLOGENY AND EVOLUTION Posters
758 - Morphotaxonomy and phylogeny of Lentinus and
Panus from the neotropics
T. Rolen * , L. Ryvarden & T. Schumacher
Division of Botany and Plant physiology, P.O. box 1045
Blindern, 0316 Oslo, Norway. - E-mail:
tage.rolen@mycoteam.no
A combined molecular and morpho-taxonomic approach
was used to delineate taxa and infer main evolutionary
lineages in members of Lentinus Fr. and Panus Fr. from
Costa Rica and the neotropics. Previous morpho-taxonomic
studies have resulted in unresolved delineation of
(evolutionary) groups and conflicting classifications in this
diverse and ecologically important group of wood decaying
fungi of the tropics. ITS nrDNA sequences and the
combined use of morphology and ITS sequences always
placed Lentinus and Panus in two distinct clades. Two
evolutionary lineages of Lentinus, and two strongly
supported subclades within the Panus clade, were detected.
The inferred phylogeny suggets that Lentinus is more
closely related to Polyporus than to Panus. Three species
assigned to the L. crinitus-complex (L. crinitus, L. bertieri,
and L. swartzii), e. g. characterized by a continuum of
morphotypes and not easily assigned to a specific taxon,
were particularly focused. Sequences from 7 specimens of
this complex indicated a relatively high level of genetic
variation, distributed among mostly unresolved groups. In
some Lentinus and Panus species parts of sequences were
consistently double-banded, indicating intraindividual ITS
polymorphism. The ITS phylogeny indicates that lamellate
hymenophores and similarity in some ultrastructural
features are not homologous structures in Lentinus and
Panus. The two divergent groups of taxa justify the
recognition of two distinct genera, Lentinus and Panus.
759 - Identification of selected Bipolaris, Curvularia and
Exserohilum species using cultural features, FOIL and
Decision Tree(DT) classification tools
I.H. Rong * , R.P. Rong & O.M. Page
ARC-PPRI, Private Bag X 134, PRETORIA 0001, South
Africa. - E-mail: vrehir@plant5.agric.za
Many closely similar species have been described within
Bipolaris, Curvularia and Exserohilum. Identification of
species is further complicated by the variability of some
morphological features of the group. In other anamorphic
genera, investigation of cultural and biochemical features
as taxonomic criteria to supplement morphology, received
attention for the same reason. The object of this study was
to investigate the potential of simple measurements on
solid media as identification tools in some helminthosporic
fungi. Authentic and representative strains of selected
Bipolaris, Curvularia and Exserohilum species, including
the type species of each genus, were obtained form various
collections. The strains were selected to vary in
geographical origin and host or substrate or origin. Colony
diameters of strains were measured on a variety of media
testing presumptive enzymatic activities, influence of
inhibitory substrates and utilization of different carbon
sources. Data accumulated were processed with two datamining
techniques FOIL and DT. The value of culture
based tests as diagnostic aid was demonstrated. Using
FOIL algorithms and 5 of 25 tests, 79% of the strains
investigated could be placed into the correct species.
Further refinements to some tests could result in an
identification tool or the development of selective media
for some of these species.
760 - Phylogenetic analysis of cetrarioid lichens with
globose ascospores
A. Saag 1* , T. Randlane 1 & A. Thell 2
1 University of Tartu, Lai 38, 51005 Tartu, Estonia. -
2 University of Hamburg, Ohnhorsstrasse 18, 22609
Hamburg, Germany. - E-mail: asaag@ut.ee
The group of cetrarioid lichens (Parmeliaceae,
Ascomycota) with globose ascospores includes 37 species
from eight genera (Ahtiana, Allocetraria, Dactylina,
Esslingeriana, Nephromopsis, Tuckneraria,
Tuckermannopsis, Vulpicida). Phylogenetic analysis was
carried out on two different data sets - morphological (incl.
anatomical and chemical) and molecular characters (ITS1,
5.8S and ITS2 rDNA sequences) - to verify the
correspondence of current taxonomy to the probable
evolution of the taxa involved. For 17 species both
morphological and molecular characters were studied while
14 other species were checked for morphology only. The
paraphyletic nature of the genus Allocetraria in regard to
two species of Dactylina is assumed on morphological
characters. Still, the separation of these genera is strongly
supported by the analysis of molecular data. The genus
Tuckermannopsis should be considered paraphyletic in
regard to Esslingeriana idahoensis and Nephromopsis weii
according to the analysis based on morphological
characters. No doubt that Nephromopsis wei does not
belong to the genus Nephromopsis and a new combination
for this taxon is needed. The analysis of molecular
characters reveals the monophyletic origin of all three
Tuckneraria species included in the analysis. Monophyly
of the genus Ahtiana is not supported by the analysis of
morphological data while the analysis based on ITS
sequences indicates a close relationship between the genera
Ahtiana and Tuckermannopsis.
761 - Systematic approach to pyrenomycete taxonomy
R.A. Shoemaker
ECORC,Agriculture Canada, Research Br., 930 Carling
Avenue, Building 49, Ottawa ON K1A 0C6, Canada. - Email:
shoemakerb@em.agr.ca
Book of Abstracts 229