Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme II: SYSTEMATICS, PHYLOGENY AND EVOLUTION Posters
Fusarium isolates. 318 isolates identified as the genus
Fusarium were collected from different areas and hosts.
Species of the isolates were identified based on
morphological characters. The pectic enzyme solution was
prepared for each isolate using liquid media containing
citrus pectin as a sole carbon source. Electrophoresis was
performed using pectin acrylamide gel. Several zymogram
phenotypes were obtained for polygalacturonase and pectin
esterase. In total, 12 zymogram patterns were determined
for 318 isolates tested. The results showed that there is a
considerable intraspecific variation for Fusarium species.
There were 3, 5 and 2 zymogram electrophoretic patterns
for Fusarium oxysporum, F. solani and F. culmorum
respectively. However, there were only one zymogram
pattern for F. subglutinans and also one for F. equiseti.
Although the intraspecific variation based on zymogram
was not correlated to the form species of Fusarium, the
species of Fusarium were distinguished using this
technique and there was no common zymogram pattern
among species.
630 - The lichen genus Caloplaca on Svalbard
L. Balschmidt * & U. Søchting
Botanical Institute, Department of Mycology, University of
Copenhagen, Øster Farimagsgade 2D, 1353 Copenhagen
K, Denmark. - E-mail: lineb@bot.ku.dk
The Svalbard Archipelago hosts a highly diverse flora of
high Arctic Caloplaca species with more than 40 species
growing primarily on rock, soil, lignum and bone. A
comprehensive study of the Caloplaca flora adds to the
understanding of Arctic species distribution and clarifies
the species concept of several formerly poorly understood
species, e.g. Caloplaca invadens.
631 - Molecular phylogeny of North American species
of Laetiporus and related genera
M.T. Banik 1 , D.L.L. Czederpiltz 2* & J.A. Micales 1
1 Center for Forest Mycology Research, USDA Forest
Service, Forest Products Laboratory, One Gifford Pinchot
Drive, Madison, WI 53705-2398, U.S.A. - 2 University of
Wisconsin-Madison, Dept. of Plant Pathology, 1630
Linden Dr., Madison, WI 53706, U.S.A. - E-mail:
dlindner@facstaff.wisc.edu
Relationships among species in the genera Laetiporus,
Phaeolus, Pycnoporellus, Wolfiporia, and Leptoporus were
investigated using nuclear 25S and ITS rDNA and
mitochondrial 18S rDNA sequences. Members of these
genera have poroid hymenophores and simple septate
hyphae, and cause brown rots in a variety of substrates.
Results based on parsimony and maximum likelihood
analyses indicate that the genus Laetiporus as currently
defined is not monophyletic. The ITS regions of all
Laetiporus species examined were easily aligned, with the
exception of L. persicinus. Analyses suggest that L.
persicinus is no more closely related to other Laetiporus
species than to species of Phaeolus, Leptoporus or
Pycnoporellus. The six other Laetiporus species examined
(L. cincinnatus, L. conifericola, L. gilbertsonii, L.
huroniensis, L. sulphureus, and an undescribed species
from the Caribbean) appear to make up a well-supported,
monophyletic group. Results confirmed that L. conifericola
and L. huroniensis, two species that occur on conifers, are
very closely related but distinct species. The existence of a
previously undescribed yellow-pored species from the
Caribbean was also confirmed. This species may be more
closely related to L. gilbertsonii than to any other species
of Laetiporus. Two varieties of L. gilbertsonii, which are
compatible in mating tests and differ only in pore color,
were indistinguishable in these analyses.
632 - Using parsimony networks, migration estimates
and coalescence approaches to resolve the
phylogeography of Mycosphaerella graminicola
S. Banke * & B.A. McDonald
Institute of Plant Sciences, Phytopathology, ETH,
Universitaetstr. 2 / LFW-B28, CH-8092 Zurich,
Switzerland. - E-mail: soren.banke@ipw.agrl.ethz.ch
DNA sequences of nuclear-encoded loci can be used to
determine the phylogeographical history of fungal
populations. Four nuclear loci were sequenced in the fungal
wheat pathogen M. graminicola. Two neutral non-coding
RFLP loci and two nuclear single copy genes were
selected. The coding genes were β-tubulin and 3isopropylmalate
dehydrogenase (LeuC). A total of 300 M.
graminicola isolates originating from 14 wheat fields
around the world were sequenced. All sequence loci
showed useful diversity. The RFLP locus STS2 had 29
polymorphic sites in a 490 bp region, while STL10 had 31
polymorphic sites in a 1265 bp region. For the β-tubulin
locus, 24 polymorphic sites were found among 366 bp
sequenced. The leuC gene contained 65 polymorphic sites
within the 870 bp region sequenced. Gene genealogies
were generated for all sequenced loci following clonecorrection
for each locus/population. Trees were rooted
using Septoria passerinii, the closest known relative of M.
graminicola. Parsimonious networks were constructed
using a nested cladistic approach, and migration rates
between populations were estimated. A coalescence
approach was used to determine the temporal scale of
historical migration events among populations. All loci
were also tested for neutrality and intergenic
recombination. Our results suggest that the centre of origin
for this pathogen is most likely in the Fertile Crescent, and
that migration occurred first into the European continent
and later into the New World.
Book of Abstracts 191