Inoculum 63(3) - Mycological Society of America

and amenity areas. The population dynamics and dispersal pathway of this
pathogen in the US have not been well studied. In attempt to elucidate this, we
isolated eight promising microsatellite markers from an enriched genomic library
of Wcc. Seven of these markers were used to study the population diversity of
eastern and western US populations of Wcc and the association with phenotypic
characteristics. In general, the microsatellite markers were highly polymorphic,
with an observed heterozygosity of > 0.5. The eastern population was differentiated
from the western population but both populations showed the presence of immigrant
individuals across boundaries. Analysis of population structure with geography
revealed a significant clinal expansion, r 2 = 0.11, P = 0.01, of Wcc within
a radius of about 150 km. However, it became more stochastic with increase in
distance. No host specific clusters were observed based on UPGMA clustering,
suggesting a lack of association between host and pathogen genotypes.
Norvell, Lorelei L 1 and Scott A Redhead 2 . 1 Mycotaxon, PNW Mycology
Service, Portland OR 97229-1309 USA, 2 National Mycological Herbarium, Eastern
Cereal & Oilseed Research Centre C.E.F., Agriculture & Agri-Food Canada,
Ottawa, ON K1A 0C6 Canada. A mycologist’s guide to the Melbourne Code.
The International Code of Nomenclature for algae, fungi, and plants
(ICN) replaced the International Code of Botanical Nomenclature (ICBN) during
the 2011 International Botanical Congress (IBC) in Melbourne. The new ICN permits
diagnoses/descriptions in English (no longer requiring Latin) and electronic
publication of fungal names (via PDFs in ISSN/ISBN numbered publications).
With registration of fungal names required for valid publication in 2013, the IBC
Nomenclature Committee for Fungi (NCF) is now moving to approve one or
more nomenclatural registries. The ICN also excludes names of microsporidians
and organisms treated in other Codes, refines typification procedures and spelling
of sanctioned names, and recommends how to designate type cultures. The Melbourne
Congress also referred mechanical typification issues and governance of
fungal nomenclature to special committees and approved NCF recommendations
on the conservation and rejection of notable fungal names. The new ICN does not
permit multiple names for fungi with pleomorphic life cycles, which the ICBN
(under Art. 59) previously allowed for non-lichenized ascomycetes and basidiomycetes.
After 2013, alternative new names will be either illegitimate or not
valid, although alternatives published through 2012 may be valid or legitimate.
Although teleomorph- and anamorph-typified names will compete equally for priority,
the ICN dictates delay in adopting anamorph-typified names with priority
over commonly used teleomorph-typified names. To buffer the effects of this
major change regarding alternative names, NCF-sanctioned subcommittees will
compile and adjudicate lists of conserved/rejected names of non-lichenized fungi
(not restricted to the Ascomycota and Basidiomycota) for approval by the IBC.
The NCF and International Commission on the Taxonomy of Fungi (ICTF) - collaborating
to issue joint guidelines, updates, and advice - recognize that mycological
opinion over the Art. 59 change is still deeply divided and must be considered.
Nuhn, Mitchell, Roy E Halling, Manfred Binder, David S Hibbett, and Todd W
Osmundson. Department of Biology, Clark University, 950 Main St, Worcester,
MA 01610. The Boletineae of Queensland, Australia
The Boletineae is a group of mushrooms with many species highly sought
after by both animals and humans as food. The majority of Boletineae species are
ectomycorrhizal with woody plants, making them important members of forest
ecosystems. This study will provide the first biodiversity inventory of the Boletineae
in Queensland, Australia, including three of Australia’s Biodiversity
Hotspots and World Heritage listed sites. To accomplish the inventory, modern
molecular and phylogenetic techniques will be used, in combination with traditional
taxonomic methods. A sequence dataset of nuclear ribosomal large subunit
(nuclsu) and translation elongation factor 1-alpha (tef1) sequences has been generated
for the systematic overview of the Boletineae of Queensland. The study has
already resulted in one publication, designating a new cosmopolitan genus and at
least two species for a previously described species, Sutorius eximius and S. australianses
(previously Tylopilus eximius). Further study is ongoing, providing an
overview of amorphologically distinct, cosmopolitan taxon, Tylopilus chromapes,
that appears to be polyphyletic based on preliminary results. An overview of additional
Boletineae species occurring in Queensland, Australia and their relationships
in the context of a worldwide phylogeny of Boletineae is in progress.
Olarte, Rodrigo A 1 , Bruce W Horn 2 , Carolyn J Worthington 1 , and Ignazio Carbone
1 . 1 Department of Plant Pathology, North Carolina State University,
Raleigh, NC 27695, 2 National Peanut Research Laboratory, Agricultural Research
Service, U.S. Department of Agriculture, Dawson, GA 39842. Matingtype
heterokaryosis and population shifts in Aspergillus flavus
Aspergillus flavus is a fungal pathogen of many agronomically important
crops worldwide. We sampled A. flavus strains from a cornfield in Rocky Mount,
NC. This field was planted in 2010 and plots were inoculated at tasseling with either
AF36 or NRRL 21882 (=Afla-Guard) biocontrol strains, both of which are
36 Inoculum 63(3), June 2012
mating type MAT1-2. Subsequently, toxigenic strain NRRL 3357 (MAT1-1) was
applied to all plots, including control plots not inoculated with biocontrol strains.
Sclerotia were harvested from infected corn ears approximately 4.5 months after
planting (2.5 months after biocontrol treatment); ninety single-ascospore isolates
were isolated from ascocarps originating from plots treated with AF36 and NRRL
21882. In addition, eighty A. flavus isolates were collected from soil one month
after planting (before biocontrol application) and one year after biocontrol application,
for a grand-total of 250 isolates. Aflatoxin (AF) and cyclopiazonic acid
(CPA) production were determined using standard thin-layer chromatography
and HPLC. Three distinct toxin classes were identified: AF-/CPA-, AF+/CPA+
and AF-/CPA+. PCR amplification revealed grouping of isolates into three distinct
mating-type classes: MAT1-1, MAT1-2 and MAT1-1/MAT1-2. A significant
proportion (54%) of isolates sampled prior to biocontrol treatments were heterokaryotic
for mating type (MAT1-1/MAT1-2), and 39% of isolates obtained
from ascospores were heterokaryotic as well as 9% of isolates from soil after biocontrol
treatments. The vertical transmission of MAT1-1/MAT1-2 to progeny ascospore
isolates suggests that heterokaryosis can be maintained in subsequent
generations. The population genetic structure before and after the application of
biocontrol treatments will be discussed. Further characterization of heterokaryons
and their frequency in A. flavus populations may be important in understanding
the adaptation of these fungi to changing environmental conditions.
Oliver, Jason P and Jonathan S Schilling. University of Minnesota, 320 Kaufert
Laboratory, 2004 Folwell Avenue, St. Paul, MN 55108-6130. Manure gas eating
microbes: Effect of fungal and bacterial biomass on biofiltration of livestock
production emissions
Though specific data is only just being analyzed, scientists and regulators
are beginning to recognize the significant emission of particulate matter, odor,
hazardous and greenhouse gases from livestock production and manure management.
Biofiltration - use of a biologically active porous media to capture and degrade
gaseous pollutants - is a low-cost and adaptable mitigation technology suitable
for manure storage emissions. Improving the design and management of
biofilters (and ultimately adoption by producers) rests on our ability to understand
the microbial ecology of the filter media, the underpinnings of biofilter effectiveness
and efficiency. Studying biofilters at multiple scales, we are beginning to resolve
the effect of fungal and bacterial biomass on reductions of gases generated
by long-term storage of livestock manure.
Orwin, Kate H 1 , Miko U F Kirschbaum 2 , Julie R Deslippe 2 , and Ian A Dickie
3 . 1 Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ,
United Kingdom, 2 Landcare Research, Private Bag 11052, Palmerston North
4442, New Zealand, 3 Landcare Research, Box 40, Lincoln 7640, New Zealand.
The impact of mycorrhizal fungal traits on ecosystem responses to global
change: a modeling approach
Ecosystems are currently being subjected to multiple global change factors,
from nitrogen deposition to increasing CO2 concentrations and changes in
temperature. Understanding the consequences of these effects on ecosystem
processes such as carbon cycling is of prime importance, as this will determine
whether ecosystems are likely to cause positive or negative feedbacks to climate
change. Current evidence suggests that carbon cycling can be strongly affected by
the traits of the plant community, with most studies focusing on litter quality and
plant growth rates. However, recent modelling work has demonstrated that the
traits of plant symbionts can also play a significant role in determining ecosystem
carbon storage. In particular, the ability of mycorrhizal fungi to directly access organic
nutrients can be as important as a major shift in litter quality for carbon storage.
The two main mechanisms behind this effect were direct access to organic
nutrients causing i) an increase in plant nutrition resulting in enhanced photosynthetic
rates and subsequent carbon inputs to the soil and ii) a reduction in microbial
access to nutrients, which reduced the rate of soil organic matter decomposition.
We have little understanding of the way in which such interactions among
mycorrhizal symbionts, their hosts and other soil decomposers may modify the effect
of global change factors on ecosystem carbon dynamics. Here, we use a
newly developed model (MySCaN: Mycorrhizal Status, Carbon and Nutrient cycling)
to examine the impact of global change factors on carbon storage, and how
these trends can be affected by mycorrhizal traits. We show that global change effects
on carbon storage are not universal, but are modified by the interaction between
plants and their mycorrhizal symbionts.
Osmundson, Todd W and Matteo Garbelotto. Forest Mycology and Pathology
Laboratory, Department of Environmental Science, Policy and Management,
University of California, Berkeley, CA 94720, USA. Fire drives habitat specialization,
speciation, and hybridization of Morel mushrooms in western
North America
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