Inoculum 63(3) - Mycological Society of America

morphological and molecular (nrITS) data. Two taxa are currently under revision
and probably represent undescribed species: (i) Lepiota novae-angliae, nom.
prov., recorded from Massachusetts and New Hampshire closely resembles L.
clypeolaria in morphology but it’s ITS sequences do not match those of L. clypeolaria
or any of the species of sect. Lepiota currently available in GenBank; (ii)
Leucoagaricus allochthonus, nom. prov., was recorded in an indoors (greenhouse-like)
garden in central Massachusetts and is probably a tropical alien
species. Microscopically, it is characterized by the presence of pleurocystidia, a
feature only shared by 3-4 other species in the very diverse Leucoagaricus/Leucocoprinus
lineage (> 100 described species). Molecular data confirmed the presence
of widespread cosmopolitan species in our area (e.g. Lepiota cristata, Leucoagaricus
leucothites) but also revealed molecular differences between isolates
of northeastern lepiotaceous fungi (e.g. Leucoagaricus rubrotinctus, Lepiota felina)
and GenBank sequences deposited under the same name but with a different
geographic origin.
Kaffenberger, Justin T and Jonathan S Schilling. Department of Bioproducts
and Biosystems Engineering, University of Minnesota, 2004 Folwell Avenue, St.
Paul, MN 55108. Insights into the potential diversity of the brown rot decay
mechanism provided by substrate compositional analysis
Wood-degrading fungi are typically designated by the type of decay that
they produce: the two main types being brown rot and white rot. While much effort
has been put into understanding the biochemical mechanism by which brownrot
occurs, the process remains poorly understood. Evidence suggests that brownrot
fungi incorporate a Fenton reaction-based oxidation to rapidly de-polymerize
substrate components and several mechanisms incorporating Fenton chemistry
have been proposed. These proposed mechanisms have been based largely on
studies performed on only a few brown-rot species. The polyphyletic nature of
brown-rot, however, suggests that there may be several routes to brown rot decay.
While these fungi all ultimately produce brown decay residues, details regarding
the chemical composition of these residues over the course of degradation have
not been explored. Details regarding this chemistry may elucidate similarities and
differences in the nature of underlying decay mechanisms. To this end, one representative
from each of the known seven clades of brown rot fungi (Gloeophyllum
trabeum, Fomitopsis pinicola, Ossicaulis lignatilis, Serpula lacrymans, Fistulina
hepatica, Wolfiporia cocos, and Dacryopinax sp.) were used to decay
representative hardwood (Populus tremuloides), softwood (Pinus radiata), and
grass (Zea mays) species. Compositional analyses of the residues were performed
at six time points over the course of 4 months of exposure. Details of these compositions
and their implications are discussed.
Kauserud, Håvard 1 , Einar Heegaard 2 , Ulf Büntgen 3 , Simon Egli 3 , Rune
Halvorsen 4 , and Lynne Boddy 5 . 1 Microbial Evolution Research Group (MERG),
Department of Biology, University of Oslo, PO Box 1066 Blindern, NO-0316
Oslo, Norway, 2 Norwegian Forest and Landscape Institute, Fanaflaten 4, N-5244
Fana, Norway, 3 Swiss Federal Research Institute for Forest Snow and Landscape
(WSL), Birmensdorf, Switzerland, 4 Department of Research and Collections,
Natural History Museum, University of Oslo, PO Box 1172 Blindern, NO-0318
Oslo, Norway, 5 Cardiff School of Biosciences, Biomedical Building, Museum
Avenue, Cardiff CF10 3AX, UK. Temporal patterns of fungal fruiting reveal
ongoing climate change effects
Effects of climate change on fungi may manifest in various ways. Time
of fruiting may change, yields of fruit bodies can be altered and distributional
ranges of species may shift. We are studying these three aspects using statistical
analyses of time series data and digitized field and herbarium records. We show
that the annual fruiting period across Europe has changed during the last 50 years.
In Austria, Norway, Switzerland and the UK, the average annual fruiting time of
autumn fruiters has been delayed. Moreover, the start and end of the annual fruiting
period, using the 5 and 95 percentiles as proxies, have changed towards earlier
and later, respectively. Changes in fruiting time have been especially dramatic
in the UK, which deviates from the other regions by a more oceanic climate. Time
series data from a Swiss forest plot indicates that the annual yields of ectomycorrhizal
fruit bodies has increased dramatically during the last 40 years. We hypothesize
that changes in the regional climate, including higher temperatures and
more precipitation, can be linked to the increased fruit body yields. In another ongoing
study we are exploring the extent to which fungi in the UK have shifted distributional
ranges during the last 50 years and whether this can be linked to climate
change.
Kepler, Ryan M 1 , Jonathan Shao 2 , and Stephen A Rehner 1 . 1 Systematic Mycology
2
and Microbiology Laboratory, USDA, ARS, Beltsville, MD, 20705,
Molecular Plant Pathology Laboratory, USDA, ARS, Beltsville, MD, 20705.
Genome-enabled marker development for evolutionary studies of the insect
pathogen Metarhizium
Genome sequence resources for fungi enable development of custom genetic
markers scaled to specific evolutionary inferences that improve greatly on
26 Inoculum 63(3), June 2012
information derived from the more limited set of generic legacy genetic markers.
Using recently available genome sequences for M. anisopliae and M. acridum, we
have developed a suite of novel genetic markers for investigating cryptic speciation,
phylogeography and population genetics within Metarhizium s.l. To exploit
the inherent variability of nuclear intergenic (nucIGS) regions we have created a
simple graphical approach to visually scan for variable nucIGS regions flanked by
conserved gene sequences that can serve as anchors for robust primer development.
Using pairwise alignments of selected genomic scaffolds from the two
species created in the Mummer 3.0 genome alignment program, a simple script
was developed that tabulates the number of SNPs via a scalable sliding window
function, facilitating visualization of trends in nucleotide substitutions and similarity
between syntenic genomic regions among pairs of sequences. We describe
the development of novel markers developed using this approach and demonstrate
their utility to infer cryptic phylogenetic partitions previously missed or poorly resolved
by pre-existing phylogenetic markers. We demonstrate the superior performance
of these new versus preexisting markers by comparison of their phylogenetic
informativeness using PhyDesign and Genealogical Sorting Indices. In
addition we: 1) summarize the numbers, types and genomic distribution of microsatellite
markers and compare these to those developed by enrichment methods,
and 2) discuss the mating locus and development of improved mating type
assignment PCR assays. Through selected examples we illustrate the improvements
in evolutionary inference achieved with these newly developed genetic
markers.
Kerekes, Jennifer F 1 , Michael Kaspari 2 , Bradley S Stevenson 3 , and Thomas D
Bruns 1 . 1 111 Koshland Hall, Dept. of Plant and Microbial Biology, UC Berkeley,
Berkeley CA 94720, USA, 2 Graduate Program in EEB, Dept. of Zoology,
University of Oklahoma, Norman, OK 73019, USA, 3 Graduate Program in EEB,
Dept. of Botany and Microbiology, University of Oklahoma, Norman, OK 73019,
USA. Nutrient enrichment increased species richness of leaf litter fungal
communities in a diverse lowland tropical forest
We explored leaf litter fungal diversity in a diverse lowland tropical forest
in which a replicated factorial N, P, K, micronutrient fertilization experiment
of 40 x 40 m plots had been on going for nine years. Fertilized plots were compared
with control plots that did not receive fertilization to evaluate possible nutrient
effects on leaf litter fungal communities. We extracted DNA from leaf litter
samples collected on the Gigante peninsula, Barro Colorado Nature Monument
(BCNM), Republic of Panama and used fungal-specific amplification and a 454
pyrosequencing approach to sequence two loci, the nuclear ribosomal internal
transcribed spacer (ITS) region and the nuclear ribosomal large subunit (LSU) D1
region. Overall, both the ITS and LSU gene regions had similar results. The use
of two separate gene regions for the analysis provided a complimentary look at
the data. Ascomycota (including approximately 29 orders, 44 families, and 88
genera) are the dominant phylum among the leaf litter fungi, followed by Basidiomycota
(including approximately 31 orders, 38 families and 52 genera). The
long-term addition of nutrients increased species richness relative to the control
plots, and had an effect on the taxonomic composition of the leaf litter fungal
communities at lower taxonomic levels (i.e. family, genus and species), but not at
higher taxonomic levels (i.e. phylum, class and order). Nitrogen has the largest effect,
followed by phosphorus and potassium.
Kerrigan, Julia and Virginia Waldrop. School of Agricultural, Forest, and Environmental
Sciences, 114 Long Hall, Clemson University, Clemson, SC 29634-
0310. Biofilm formation by Aspergillus niger, Aureobasidium pullulans, and
Cladosporium cladosporioides
A biofilm is an aggregate of microorganisms adhered together, to each
other and to a substrate, surrounded by an extracellular matrix. Biofilms are ubiquitous,
occurring in natural and artificial water systems, and are of great concern
because of their persistence in industrial, medical, and household environments.
Although bacterial biofilm research is well established, fungal biofilm research is
comparatively new and the vast majority of the research has been conducted on
yeasts. This research was undertaken to develop a repeatable system for studying
biofilm formation by different types of filamentous fungi and to document their
phenotypic changes throughout biofilm development. Aspergillus niger, Aureobasidium
pullulans, and Cladosporium cladosporioides were studied because
they are cosmopolitan, commonly found in biofilms, and have characteristic culture
morphology allowing for easy detection of contaminants. We established a
method for engineering biofilms in a controlled reactor that models those growing
under low sheer. This method can be modified for different types of filamentous
fungi and other microbes. The first stage of filamentous fungal biofilm formation
involves spore attachment and germination. Hyphal tip growth produces
an extracellular polysaccharide that helps the fungus grow and allows for attachment
within the liquid environment. Hyphae form an interconnected network that
attaches to itself and other surfaces. As hyphal proliferation continues, spores are
produced, germinate, and give rise to additional biofilm mass. A mature biofilm
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