Inoculum 63(3) - Mycological Society of America

phisms, which distinguished only half of the strains. We are now transitioning to
VNTR genotyping and whole genome Illumina sequencing to characterize the diversity
more completely. Lastly, in order to test for formation of ascomata (sexual
structures), we will co-culture ten of our T. rubrum isolates and a T. tonsurans
isolate (MAT1-2) in single, pair-wise and triple combinations on dermatophyte
mating medium. Cultures with extensive hyphal coiling (indicative of early sexual
development) will be dissected and examined for presence of ascomata or ascospores.
Thus far, our results provide no evidence of sexual reproduction and reconfirm
low sequence variation in T. rubrum clinical isolates.
Garbelotto, Matteo M and Todd W Osmundson. Department of Environmental
Science, Policy and Management, University of California, Berkeley, CA 94720,
USA. Is there a “best” unit of conservation for valuable mushroom species?
A scientific approach based on studies on matsutakes, morels and truffles
In the presence of limited economic resources, an approach is needed to
maximize the results of conservation efforts focused on valuable mushroom
species. Although the genomic nature of desirable mushroom phenotypes is still
mostly unknown, we propose that a biogeographical approach combined with
population genetics studies provide a concrete way to enact mushroom conservation
plans. In the absence of precise knowledge of why a specific population
should be protected, we suggest that the unit of conservation should be that of the
“metapopulation” within each broad geographic region. It was first suggested in
the late 1990s that habitat fragmentation was a major driver of speciation in Matsutakes.
That intuition was recently confirmed by formal analysis on the effects
of forest fragmentation on fungal community structure. The logistical advantage
of focusing on habitat conservation, rather than on individual fungal species, is
obvious. We show here that for recently evolved species, distribution of species
tracks the presence of continuous forest cover, and an “isolation-by-distance” approach
can be used to identify valuable conservation units. However, we present
four examples of exceptions that need to be taken into account: a) The presence
of significant geographic barriers, such as high mountain ranges, may accelerate
drift; b) Significant bottlenecks caused by geologically recent events like glaciations
may have led to genetic isolation between populations surviving in different
refugia; c) Natural ecological events such as fires may be triggers of speciation
and of hybridization among mushrooms; and d) Forest management may accelerate
genetic drift by favoring short rotations where gene flow among populations
is hindered.
Gause, Justin W and Merlin M White. Boise State University, Dept. of Biological
Sciences, Boise, ID 83725. Entangled and nearly deceived in a web of gut
fungi: two intermingled, dimorphic Smittium species from Idaho
Since 2007 we have been prospecting for gut fungi near Boise, Idaho. The
Boise River, which runs parallel to Boise State’s campus, sporadically has been a
convenient and favorable system for aquatic insect collection, despite that it runs
through this metropolitan area. Collections have included midges (Chironomidae),
which are hosts of several genera of Harpellales, including Smittium. In
2008, several collections of larval midges revealed an astonishing density of
hindgut dwelling gut fungi. Upon morphometric analysis of vouchered slides, two
species of Smittium, both with dimorphic trichospores, were found to be coexisting
inhabitants in the midge population. In addition to the dimorphic trichospores,
zygospores were also recovered. Zygospores are often the missing “piece of the
puzzle” for taxonomic considerations, and we were fortunate enough to have
them within a few dissections. However, these specimens were remarkably well
developed and presented intermingled thalli, demanding careful scrutiny to tease
apart the key morphological aspects belonging to each. We present our data on the
two species of Smittium and compare them with records of putatively closely related
Smittium species, with suggestions for future efforts with these and other
host populations in pursuit of gut fungi worldwide, perhaps in an area near you?
Geiser, David M 1 , Alejandro P Rooney 2 , Todd J Ward 2 , Takayuki Aoki 3 ,
Seogchan Kang 1 , Stephen A Rehner 4 , and Kerry O’Donnell 2 . 1 Department of
Plant Pathology, Penn State University, University Park, PA 16802, 2 USDA-
ARS-NCAUR, 1815 N. University St., Peoria, IL 61604, 3 MAFF, NIAS, 2–1–2,
Kannondai, Tsukuba, Ibaraki 305–8602, Japan, 4 Systematic Mycology and Microbiology
Laboratory, USDA, ARS, Beltsville, MD 20705. Phylogenetically
marking the limits of the genus Fusarium for post-Article 59 usage
Fusarium (Hypocreales, Nectriaceae) is one of the most important and
systematically challenging groups of mycotoxigenic, plant pathogenic and human
pathogenic fungi. We conducted maximum likelihood (ML), maximum parsimony
(MP) and Bayesian (B) analyses on partial nucleotide sequences of genes encoding
the largest (RPB1) and second largest (RPB2) RNA polymerase II subunits
on 94 fusaria to infer phylogenetic relationships within the genus and 20 of
its near relatives. Our analysis revealed that Cylindrocarpon spp. formed a basal
monophyletic sister to a ‘terminal Fusarium clade’ (TFC sensu Gräfenhan et al.
2011), which comprised 20 strongly informally named clades. Inclusion of the
basal most divergences within the TFC received strong support only from the
18 Inoculum 63(3), June 2012
Bayesian analysis (posterior probability (B-PP) = 0.99-1), with clades including
F. ventricosum and F. dimerum forming the two earliest diverging lineages. An
internode supporting the remaining TFC, however, was strongly supported by MP
and ML boostrapping (ML-BS 100%, MP-BS 87%) and a B-PP of 1. This contrasts
with the published analysis of a phylogeny based on RPB2 and acyl citrate
lyase gene sequences, which did not yield significant support for this clade. Diversification
time estimates were made to infer the origins of the genus and its
clades. Because 1) the TFC includes all economically important fusaria, 2) virtually
all of its members produce a recognizable Fusarium anamorph, 3) the Fusarium
anamorph names are widely used compared to the associated teleomorphs;
applied mycologists rarely if ever see the latter, and 4) it corresponds most closely
to a fairly stable concept of the genus that has existed for nearly a century, herein
we formally combine several teleomorph genera within the TFC and their types
into Fusarium. The present study provides a robust framework to guide future
comparative phylogenetic and phylogenomic analyses, including work to test and
extend the hypotheses developed herein.
Geml, Jozsef 1 , Eduardo R Nouhra 2 , Christian Y Wicaksono 1 , Nicolas Pastor 2 ,
Lisandro Fernandez 2 , and Alejandra G Becerra 2 . 1 Nationaal Herbarium Nederland,
Nederlands Centrum voor Biodiversiteit Naturalis, Universiteit Leiden, P.O.
Box 9514, 2300RA Leiden, The Netherlands, 2 Instituto Multidisciplinario de Biología
Vegetal (CONICET), Universidad Nacional de Córdoba, cc 495, cp 5000
Córdoba, República Argentina. Mycota of the Andean Yungas forests: assessments
of fungal biodiversity and habitat partitioning in a threatened ecosystem
The Yungas, a system of subtropical montane forests on the eastern slopes
of the Andes, reach their southern limit in northwestern Argentina. These forests
are extremely diverse and, despite covering only 2% of the country’s area, they
harbour about 50% of Argentina’s biodiversity. Unfortunately, the Yungas are
among the ecosystems most threatened by anthropogenic pressure and climatic
changes. Previous mycological works in the Yungas focused on wood-decay
fungi (e.g., polypores) and mycorrhizae in Alnus acuminata cloud forests, while
diverse Yungas communities still remain virtually unexplored. We carried out
massively parallel pyrosequencing of ITS rDNA from soil samples to provide the
first kingdom-wide fungal biodiversity assessment for the Yungas. Samples were
taken in the three major forest types along an altitudinal gradient: the piedmont
forest (400-700 m asl), the montane forest (700-1500 m asl), and the montane
cloud forest (1500-3000 m asl). Using a 97% similarity cut-off value, we delimited
1839 fungal operational taxonomic units (OTUs) in total. The majority belonged
to the phylum Ascomycota (52.49%), followed by Basidiomycota
(18.85%), Glomeromycota (0.012%), and various zygomycete lineages (0.02%),
while 24.91% showed highest similarity to other unidentified environmental sequences
and could not be assigned to phylum. The distribution of the total 1839
OTUs among the major altitudinal vegetation types were as follows: 909 OTUs
in the piedmont forest, 826 in the montane forest and 929 in the montane cloud
forest. Fungal communities were significantly different among all three forest
types, with many OTUs showing strong habitat preference for a certain altitudinal
zone. Our data offers an unprecedented insight into the fungal biodiversity of
the Yungas and into the zonal changes in fungal community structure, with potential
applications in conservation strategies to preserve the unique biodiversity
of the Andean forests.
Gonzalez, Maria C 1 , Anthony E Glenn 2 , Edmundo Rosique-Gil 3 , Kevin D
Hyde 4 , and Richard T Hanlin 5 . 1 Departamento de Botánica, Instituto de Biología,
Universidad Nacional Autónoma de México, Mexico City, DF 04510,
Mexico, 2 Russell Research Center, Toxicology & Mycotoxin Research Unit,
USDA, ARS, Athens, GA 30605, USA, 3 División Académica de Ciencias Biológicas,
Universidad Autónoma Juárez de Tabasco, Villahermosa Tab 86039,
Mexico, 4 5
School of Science, Mae Fah Luang University, Chiang Rai, Thailand,
Museum of Natural History Annex, University of Georgia, Bogart, GA 30622,
USA. A new species of Aliquandostipite from an urban lagoon of Tabasco,
Mexico
During a continued survey of Ascomycota diversity from different lentic
freshwater habitats, we recorded several interesting fungi from a lagoon located
in the urbanized area of the Villahermosa City, capital of the State of Tabasco. An
uncommon specimen was obtained using a submerged wood-baiting technique.
This Mexican microorganism shows some of the typical characteristics of Aliquandostipite
type species, A. khaoyaiensis i.e. subglobose, ostiolate ascomata; 8spored,
bitunicate, asci; bi-celled, multiguttulate, sheated ascospores and pigmented
hyphae up to 40 µm wide. However, in addition, it has other relevant
features such as the presence of very long, subcylindrical, contorted, branched, ascomatal
neck that when young is covered with hyaline, straight, attenuated, 20-50
µm x 2-4 µm hairs, a characteristic is not described in Aliquandostipite species.
Other characteristics that the new fungus exhibits include different average size of
mature ascomata, asci and ascospores, the distinctly bitunicate, thin-walled, deli-
Continued on following page