Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme IV: POPULATION DYNAMICS AND ECOLOGY Posters
939 - Mycology within the Georgia Coastal Ecosystems
Long-Term Ecological Research Project (GCE/LTER),
subproject Decomposer Consortia Experiments (DCE)
A. Buchan 1 , J.I.L. Moreta 1 , S.Y. Newell 2* & M.A. Moran 1
1 Department of Marine Sciences, University of Georgia,
Athens, GA 30602-3636, U.S.A. - 2 Marine Institute,
University of Georgia, Sapelo Island, GA 31327-0032,
U.S.A. - E-mail: newell@uga.edu
The GCE/LTER focuses on potential effects of alteration
of the quantity and quality of freshwater flow from the
Altamaha River into Georgia (USA) saltmarshes.
Ascomycetes are major secondary producers within
Georgia saltmarshes (about 550 g m -2 y -1 ). One goal of the
DCE subproject is seasonal measurement of ascomycetous
and prokaryotic biodiversity in/on the decaying shoots of
smooth cordgrass (Spartina alterniflora), using both direct
microscopy (ascospores) and DNA technology (base
sequences in rDNA/ITS, using ascomycete-specific PCR).
The DCE subproject also includes examination of genes for
lignocellulose-degrading enzymes of prokaryotes and
ascomycetes - the ascomycetous enzyme targeted is
laccase. Selected findings follow. 1) We found no rDNA of
major, cryptically occurring ascomycetes - the same three
species that are the principal ascomatal producers were also
the major rDNA sources (Phaeosphaeria spartinicola,
Mycosphaerella sp.2, P. halima). 2) The species with the
highest rates of ascospore expulsion (P. spartinicola) may
not be the species with the highest biomass yield -
Mycosphaerella sp.2 exhibited the greatest rDNA-detection
peaks (T-RFLP). 3) All major and minor ascomycete
species examined had one or more laccase genes (15
distinct types total), and laccase genes of the three
predominant ascomycetes (+ two unidentified laccase
genes) were found within naturally decaying leaf blades,
with the greatest % of clones belonging to laccases of P.
halima.
940 - The diversity of mycophagous diptera and their
macrofungi hosts
B.A. Bunyard 1* & B.A. Foote 2
1 Ursuline College, Dauby Science Center, Pepper Pike,
Ohio 44124, U.S.A. - 2 Kent State University, Department of
Biological Sciences, Kent, Ohio, U.S.A. - E-mail:
bbunyard@ursuline.edu
Despite their ubiquity in nature, few studies have been
conducted worldwide to determine the ecological
importance of mycetophagous diptera (fungi-feeding flies).
For this study 134 species from 30 families of
Basidiomycetous fungi and 19 species from 11 families of
Ascomycetous fungi were collected from different sites in
northeastern Ohio. Different sites were selected to obtain a
diversity of mushroom substrate, as well as biotic and
abiotic conditions, and consisted of mature forest, mixed
mesophytic forest, urban forest, and urban residential.
Adult flies were reared from 87 different fungal
collections. Families of Diptera that seem to include
mycophagous species are: Drosophilidae, Chloropidae,
Phoridae, Mycetophilidae, Sciaridae, Tipulidae,
Cecidomyiidae, and Platypezidae. Several other dipteran
families are probably scavengers (Anthomyiidae,
Sarcophagidae), occurring only infrequently in decaying
mushrooms. Many mycetophagous flies are poorly known;
several have larval stages that remain completely
undocumented. While some fungal species seem to host a
single fly species per mushroom, most do not. How
mycophagous dipteran species can avoid competition is
uncertain. Unless factors are in operation to prevent it
(niche partitioning, predation, parasitism), mycophagous
diptera may pose a challenge to the competitive exclusion
principle. Preliminary evidence suggests parasitism by
species of parasitic wasps and predation by ants and beetles
may play a role.
941 - r DNA ITS-sequence analysis of ericoid
endophytes from Australia and the USA
S.C. Burns 1 , C.B. McLean 1* , M.C. Starrett 2 & A.C.
Lawrie 3
1 University of Melbourne, Institute of Land and Food
Resources, School of Resource Management, Burnley
College 500 Yarra Boulevard, Ricmond, Victoria, 3121,
Australia. - 2 University of Vermont, College of Horticulture
and Life Sciences University of Vermont, Burlington,
Vermont, U.S.A. - 3 RMIT University, Department of
Biotechnology & Environmental Biology, GPO Box 71,
Bundoora, Vic, 3083, Australia. - E-mail:
cmclean@unimelb.edu.au
One hundred and seventeen slow-growing, sterile root
endophytes were isolated from Leucopogon parviflorus
Lind. (Epacridaceae) collected at two coastal sites in
southeastern Australia in Autumn, 2001. Twelve isolates
were then selected for the sequencing study along with four
root endophytes isolated from Pieris floribunda (Ericaceae)
collected in the southeast of the United States. All sixteen
sequences along with sequences from the Northern
Hemisphere mycorrhizal fungi Hymenoscyphus ericae and
Oidiodendron maius and the closest GenBank matches
were aligned using programs made available by the
Australian National Genomic Service. Most Australian
sequences from this study clustered with unnamed, sterile,
isolates from previous studies of the Epacridaceae, not
related to H. ericae. Three of the Australian sequences
matched closely (96%) with O. maius and conidia
produced confirmed them as Oidiodendron spp. Two of the
fungi isolated from P. floribunda were 99% similar to H.
ericae sequences in the GenBank the other two fungi
clustered with Australian dark sterile isolates.
Book of Abstracts 283