March 2008 - Mycological Society of America

Henkel, Terry W. Department of Biological Sciences, Humboldt State
University, Arcata, CA 95521, USA. twh5@humboldt.edu. The importance
of primary tropical forests for fungal biodiversity.
Guyana is fast becoming unique among tropical countries in having the
majority of its primary forest estate intact, including biodiversity at all
trophic levels. Mycological inventories have historically been wanting
in Guyana. Recent explorations have revealed a diverse macromycota
in Guyana’s Pakaraima Mountains. Forests dominated by ectomycorrhizal
(EM) trees, a relative rarity in lowland Neotropical regions, exist
in a patch mosaic in the Pakaraima Mountains and appear to be regionally
exclusive habitats for a large assemblage of endemic EM
fungi. While ecological threats to Guyana’s ectotrophic forests are currently
minimal due to the remoteness of the region, the majority of the
landscape known to house these systems has no formally protected status.
The likelihood of these Gondwanan relictual ectotrophic forests
and their apparently unique fungal constituents persisting into the future
will be discussed. Symposium Presentation
Hernandez Roa, Jonatan* and Cafaro, Matias J. Department of Biology,
University of Puerto Rico, Mayaguez Campus, Mayaguez, PR 00681.
jonatan.her@gmail.com. Biodiversity of trichomycetes associated
with marine arthropods in Puerto Rico. The increasing interest in biodiversity
has raised an effort to define it, to characterize it and to understand
how it is lost. There are few studies about trichomycete diversity in
coastal ecosystems in general and even less in tropical coasts. Puerto
Rico is an ideal place to conduct the current research on such diversity
due to the variety of habitats and ecological zones available for trichomycete
hosts, especially marine crustaceans. Only three surveys for
trichomycetes in Puerto Rico exist in which Amoebidium, Genistellospora,
Parataeniella, Harpella, Leidyomyces, Paramoebidium, Stachylina,
Smittium, Asellaria, Enterobryus and Taeniellopsis are reported, the last
three being associated to marine crustaceans in the isopod Ligia sp., the
crab Uca sp., and the amphipod Orchestia sp., respectively. More recently,
we have discovered Enterobryus halophilus in the mole crab
Emerita portoricencis, which is a new record for this trichomycete for
both its host species and distribution. Currently, we are conducting prevalence
and abundance studies in beach populations of this organism in
Puerto Rico. In this report, we present data of trichomycetes distributions
for the Caribbean, which broadens their geographic distribution, adding
new information about host range and specificity as well as their ecological
preferences reflecting the potential of trichomycetes in terms of their
biodiversity. Symposium Presentation
Herrera, Jose. 100 E. Normal, Division of Science, Truman State University,
Kirksville, MO 63501, USA. jherrera@truman.edu. The
sporocidal and sporostatic effect of sodium polyborate-treated cellulose
insulation on common indoor fungal species. Continuing interest
in mold and mold-related health problems within indoor environments
has spurred the building industry to develop
ecologically-friendly, cost-effective, safe and useful antifungal additives
for building materials. Treated cellulose insulation, made from recycled
newsprint and amended with a variety of chemical compounds,
has gathered attention and interest from a wide variety of sources including
the building industry, environmentalists, and occupational hygienists.
This study reports an assessment of antifungal properties of
treated cellulose insulation (as a whole) and one of the most common
principal active ingredients, sodium polyborate. Boron-treated cellulose
and untreated paper homologs (controls) were challenged with a
suspension containing a high concentration of fungal spores of six
species of common molds. Results suggest that (a) paper entering processing
facilities does not harbor large concentrations of mold; (b)
treated cellulose insulation is sporocidal to the six species of fungi used
in this study, and possibly many other fungal species; and (c) unilateral
exposure to sodium polyborate, the principle active ingredient in the
samples of treated cellulose, is sufficient to preclude spore germination
of these same species (actually killing spores of some). Poster
Hesse, Cedar N. 1 *, Dunham, Susie M. 2 and Spatafora, Joseph W. 2
1 Oregon State University, Department of Botany and Plant Pathology,
20 Inoculum 59(2), March 2008
2082 Cordley Hall, Corvallis, Oregon 97331, USA, 2 Oregon State University,
Department of Forest Science, 3200 SW Jefferson Way, Corvallis,
Oregon 97331, USA. hessec@science.oregonstate.edu. Eukaryotic
community structure of mat-forming ectomycorrhizal
fungi from the H.J. Andrews Experimental Forest. Mat-forming ectomycorrhizal
(EM) fungi are known to colonize significant portions of
the soils of temperate conifer forests and form beneficial symbioses
with forest trees. While it is relatively easy to identify the major matforming
fungi, little is known about the biotic communities associated
with these mats. To better understand the ecology and evolution of EM
mats the “Microbial Observatory at the H. J. Andrews LTER” has been
investigating the diversity, structure and function of EM mats in the
Cascade Mountains of Oregon, USA. Research focused in late seral
Douglas-fir stands has identified two major EM mat types, which exhibit
different abiotic soil properties. Phylotyping studies identified the
mat-forming species as belonging to the genera Piloderma and Ramaria.
Piloderma mats tend to form in the organic horizon and are conspicuously
rhizomorphic, whereas Ramaria mats tend to form in the
mineral horizon and are hydrophobic. Here, we report preliminary findings
on the eukaryotic community structure in the two different mat
soils using ribosomal DNA clone libraries. This research, coupled with
a complementary study designed to assess the prokaryotic community
structure, will provide a framework for future transcriptomic or
metagenomic research on these EM mats. Contributed Presentation
Higgins, K. Lindsay 1 *, Arnold, A. Elizabeth 2 , Kursar, Thomas 1 and
Coley, Phyllis D. 1 1 Department of Biology, University of Utah, Salt
Lake City, UT 84112, USA, 2 Department of Plant Sciences, University
of Arizona, Tucson, AZ 85721, USA. higgins@biology.utah.edu.
Diversity and ecological interactions of fungal endophytes in tropical
grasses. Tropical fungal endophytes are extremely diverse, but the
extent to which environmental factors such as rainfall, light availability,
host phylogeny, or host origin (native or exotic) affect endophyte
community composition has been not been well characterized. In addition,
nearly all studies examining the diversity and abundance of tropical
endophytes have been conducted in dicots. In this study, tropical
grasses were sampled at three sites across the Panamanian isthmus in
order to describe patterns of endophyte abundance and diversity, and
determine the extent to which environmental factors or features of the
plant host affect endophyte community composition. Cultures of 1127
isolates were obtained from healthy, asymptomatic leaves of 19 grass
species sampled across a rainfall gradient. Sequences of the nuclear internal
transcribed spacer (nrITS) region were obtained for 244 isolates,
yielding 43 unique genotype groups conservatively delimited by 90%
sequence similarity. Sequenced endophytes displayed BLAST affinity
to diverse lineages of Ascomycota. Asymptomatic genotype accumulation
curves revealed high endophyte diversity, and ecological analyses
indicated that light and moisture environment, as well as host origin
(i.e. native or exotic) play important roles in shaping the structure
of grass endophyte communities. Poster
Horn, Bruce W. 1 * and Peterson, Stephen W. 2 1 National Peanut Research
Laboratory, Agricultural Research Service, U.S. Department of
Agriculture, Dawson, GA 39842, USA, 2 National Center for Agricultural
Utilization Research, Agricultural Research Service, U.S. Department
of Agriculture, Peoria, IL 61604, USA. bhorn@nprl.usda.gov.
Host specificity of Eupenicillium ochrosalmoneum, E. cinnamopurpureum,
and two new Penicillium species associated with the conidial
heads of Aspergillus. The genus Penicillium comprises species
that mostly colonize plant matter. However, early reports suggest that
several species are capable of parasitizing Aspergillus. More recently
Eupenicillium ochrosalmoneum and E. cinnamopurpureum, both with
Penicillium anamorphs, have been observed sporulating on the heads
of Aspergillus species belonging to section Flavi during the colonization
of peanut seeds. Little is known about the host specificity underlying
these Aspergillus–Penicillium associations. In this study, Aspergillus
species representing nine taxonomic sections were paired in
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