Inoculum 56(4) - Mycological Society of America

one new IGS1 RFLP banding pattern for each of A. mellea and A. gallica. Armillaria
mellea is widely represented in the stump populations in our plots, raising
concern that models of stump sprout regeneration may be optimistic, especially in
stands experiencing oak decline. Stump sprout regeneration can result in the establishment
of crop trees on previously infected root systems. Our study also focuses
attention on the disparity between stem age and the age of their root systems
including existing Armillaria infections, in stands managed using stump sprout regeneration.
poster
Bruns, Thomas D.*, Boynton, Primrose, Shamieh, Karimeh, Szaro, Timothy M.
and Kennedy, Peter G. Department of Plant & Microbial Biology, University of
California, Berkeley 94720-3102, USA. pogon@berkeley.edu. Spatial and temporal
structure of Rhizopogon sporebanks.
Rhizopogon species are ectomycorrhizal associates of the Pinaceae. In
young, disturbed pine forests they are often among the dominant fungi colonizing
seedlings and saplings. This dominance is due to abundant sporebanks that are
produced by deposition of spores in place and by dispersal through mammal mycophagy.
We have used rodent baiting, bioassays, spore burial, and PCR-based
analyses to examine the distance and frequency of dispersal from forest to nonforested
borders and the longevity of spores. We then compared these parameters
to the spatial distribution of sporebanks. We found Rhizopogon is efficiently dispersed
at distances of 40 meters from a border in a single year, and that the distances
and quantity of spores dispersed are greatest from young post-fire forests.
Current dispersal appears to be sufficient to account for the spatial pattern of the
sporebank for the four most common species. However our results suggest that
longevity of the spores may be substantial, and we think that longevity is likely to
be important at greater spatial and temporal scales. symposium presentation
Burdsall, Harold H. Jr. USDA - FPL - Cntr. Forest Mycol. Res., Madison, WI and
Fungal & Decay Diagnostics, LLC, Black Earth, WI, USA. burdsall@fungaldecay.com.
Cyphellaceae in the Arctic and subantarctic islands.
Members of the family “Cyphellaceae” in the traditional sense are now
known to be distributed among several families of the homobasidiomycetes.
However, they are recognizable in the field as a “morphological group”, unnatural
as it may be. Collecting in the subantarctic islands of New Zealand and near
and above the Arctic Circle in Alaska has provided a number of specimens for
comparing the occurrence of these fungi from opposite ends of the globe. Species
of Lachnella, Henningsomyces and Cyphellopsis were collected. Species of Lachnella
were common on the subantarctic islands while Henningsomyces and
Cyphellopsis were lacking. The reverse was true in the Arctic collecting sites. Differences
in types of substrate may explain this difference, there being more wood
in the Arctic collecting sites than on the subantarctic islands. However, the lack of
Lachnella specimens from the Arctic may be a result of collecting bias and collecting
on forbs and ferns on the Arctic sites may provide more specimens of
Lachnella species. These comparisons are continuing. symposium presentation
Burgess, Joshua W. 1 , Schwan, William 2 and Volk, Thomas J. 2 *. Departments of
1 Microbiology and 2 Biology, University of Wisconsin-La Crosse, La Crosse WI
54601, USA. volk.thom@uwlax.edu. Detection of Blastomyces dermatitidis
DNA from natural samples using rapid PCR-based methods.
Blastomyces dermatitidis is the dimorphic fungal agent of blastomycosis, a
disease that primarily affects humans and dogs. The clinical appearance of this
mycosis is well characterized, but there is still little known about its environmental
niche, having been isolated from nature only 21 times. We have developed a
PCR-based assay to detect B. dermatitidis from soil samples using primers specific
to a portion of the promoter region of the virulence gene BAD1. An internal
standard control, pTJV2-2, was designed to ensure that negative results from soil
samples were not the result of PCR failure due to soil inhibitors. The lower detection
limit of the plasmid, using Blastomyces specific primers (BSP), was 0.1
femtograms. With chromosomal DNA, the lower detection limit is 500 fg. To test
the assay for cross reactivity, the BSP were tested successfully against many
fungi, bacteria, and actinomycetes, especially those genetically related or found in
the same geographic areas. This method is sensitive to 304 copies when detecting
pTJV2-2 DNA spiked directly into the soil extraction. When extracting live Blastomyces
yeast, this newly developed method can detect as few as 8,450 live cells.
We plan on using this method to screen soils to better determine the environmental
niche of Blastomyces. contributed presentation
Buyck, Bart 1 *, Parrent, Jeri Lynn 2 and Vilgalys, Rytas J. 2 . 1 Dépt. Systématique et
Evolution, Muséum National d’Histoire Naturelle, 75005 Paris, France, 2 Dept. of
Biology, Duke University, Durham, NC 27708-0338, USA. buyck@mnhn.fr.
The Russula virescens-crustosa species complex (Russulales, Basidiomycotina)
from eastern North America.
The type species of the subsection Virescentinae, R.virescens Fr. was originally
described from Europe, but is common throughout most of the northern hemisphere,
including the eastern US. R. crustosa Peck and R. heterosporoides Murrill
are currently the only other North American species placed in this subsection.
Since their original description, revisions of these taxa did not reveal major identification
problems, although microscopic observation was needed to separate
green forms of R. crustosa and R.virescens . Recent field work by the senior au-
MSA ABSTRACTS
thor and several American amateur mycologists suggests additional taxa are likely
to belong in Virescentinae. In this study we have combined morphological and
molecular data generated from over 100 north American, as well as some selected
Asian, African and Australian collections to examine the virescens-crustosa
complex. This work is part of a complete revision of the genus Russula in the eastern
US by the senior author. Detailed morphological study revealed that commonly
used characters for identifying Russula species, spore ornamentation and
form of hyphal extremities, are too variable within the virescens-crustosa complex
to discriminate among taxa, except for R. parvovirescens sp.nov. Results
from the multilocus molecular analysis confirm the placement of several undescribed
north American taxa in thevirescens-crustosa complex, highlight the speciose
nature of this subsection, and allow for a firm placement of these species in
a more worldwide phylogenetic dataset. Poster
Cafaro, Matias J. 1 and Lichtwardt, Robert W. 2 *. 1 Department of Bacteriology,
University of Wisconsin, Madison, WI 53706, USA, 2 Department of Ecology and
Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA. cafaro@wisc.edu.
Unveiling cryptic relationships of the Eccrinales.
The order Eccrinales includes a diverse group of arthropod-associated organisms,
most of which present relatively simple morphology. Unbranched, nonseptate,
multinucleate thalli and sporangiospores that are formed basipetally from
the thallus apex have been used as characters to relate the group to the class Trichomycetes.
No member of the Eccrinales has been cultured. In order to address
the phylogenetic relationships of the group, DNA was extracted from material
collected from different arthropods and ribosomal genes were amplified using
specific primers. Twelve sequences for the 18S gene and five for the 28S gene
were generated. Maximum parsimony, maximum likelihood and Bayesian analyses
confirmed the monophyly of the Eccrinales as well as their close relationship
to the Amoebidiales in the protist class Mesomycetozoea rather than the fungal
class Trichomycetes. The classification of the Eccrinales in three families is not
supported and needs revision. There is some phylogenetic structure that indicates
that Eccrinales associated with crustaceans are a monophyletic group different
from those species associated with millipedes. At a more refined scale, three
species associated with isopod hosts (Palavascia patagonica, Alacrinella linmoriae
and Astreptonema sp.) form a well supported clade. Future addition of taxa
and other genes may improve patterns presented in these analyses. symposium
presentation
Cai, Lei*, Jeewon, Rajesh and Hyde, Kevin D. Centre for Research in Fungal Diversity,
Department of Ecology & Biodiversity, The University of Hong Kong,
Hong Kong, SAR, China. leicai@hkusua.hku.hk. Phylogenetic relationships of
Podospora and allied genera based on multi-gene sequences and morphology.
Podospora and allied genera were investigated for phylogenetic relationships.
Multiple gene sequences (partial nuclear 28S ribosomal DNA, nuclear
ITS/5.8S ribosomal DNA and partial nuclear beta-tubulin) were analyzed using
maximum parsimony and Bayesian analysis with Markov Chain Monte Carlo algorithms.
Analyses of different gene datasets were performed individually and
then combined to generate phylogenies. In all analyses, Podospora was found to
be a highly polyphyletic genus, consisting of a group of morphologically heterogeneous
and phylogenetically distant species. Podospora species possessing ascomata
adorned with swollen agglutinated hairs or prominent protruding peridial
cells formed a strongly supported monophyletic clade in all analyses. The generic
name Schizothecium is reintroduced to accommodate species possessing above
morphological characters. Zopfiella is restricted to species having ascospores with
septum in the dark cell. Other species lacking spore septum in the dark cell (socalled
Tripterospora species) should be transferred to other genera. The redefined
Zopfiella becomes a natural group. Cercophora is also found to be a polyphyletic
genus and should be restricted to a few species bearing morphological similarity
to the type species. The family Lasiosphaeriaceae was found to be polyphyletic
based on morphological and molecular data. poster
Cantrell, Sharon A. Science & Technology, Universidad del Turabo, P. O. Box
3030, Gurabo, PR 00778, USA. scantrel@suagm.edu. Fungal inventory of the
discomycetes of the Greater Antilles.
The Greater Antilles (Cuba, Hispaniola, Puerto Rico & Jamaica) are considered
a diversity hotspot of the world. Discomycetes, particularly inoperculate, have
been poorly studied in the GA. A total of 117 Pezizales, 171 Helotiales, 28
Rhytismatales and 451 Ostropales have been reported from 11,268 fungal species.
For Dominican Republic and Puerto Rico, 75 % of the species are characteristic of
the tropics and 25 % are temperate. A study in the Dominican Republic revealed
the lack of information on this group where 17 % of the taxa recorded were new
species and 38 % were new reports. Many species of discomycetes are very small
and tend to be habitat and substrate specific. This helps to explain the lack of information
on the inoperculate discomycetes. The fungal inventories that have been
conducted in the region have not incorporated systematic and standardized methods.
Because of this, a study was conducted to develop an optimal sampling
method for discomycetes. In summary, the sampling method should select study
areas based on diversity and distribution of plant species, be conducted along transects
with a minimum of 10 plots of 1 m 2 at 5-10 m intervals and be conducted for
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