AUSTRALASIAN MYCOLOGICAL SOCIETY CONFERENCE
ABSTRACTS 2003
Molecular data reveal
ongoing speciation within the Cryptococcus neoformans species complex
Meyer W1,
Boekhout T2, Kwon-Chung KJ3, Castaneda E4,
Wanke B5, Lazera M5, Theelen
B2, Kidd S1, Latouche N1, Jackson
S1,6, Castaneda A4, Siafakas R1,6, Marszewska
K1, Huynh M1 & South American/ Spanish Cryptococcal
Study Group
1Molecular
Mycology Laboratory, Centre for Infectious Diseases and Microbiology, The University
of Sydney at Westmead Hospital, Sydney, Australia; 2 Centraalbureau
voor Schimmelcultures, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands; 3Laboratory
of Clinical Investigation, NIH, Bethesda, Maryland, U.S.A.; 4Grupo
de Microbiologia, Instituto Nacional de Salud, Bogota, Colombia; 5 Servico
de Micologia, Instituto de Pesquisa Cl'nica Evandro Chagas - Fundacao
Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil; 6School of Science,
Food and Horticulture, College of Science, Technology and Environment, University
of Western Sydney,
Campbelltown Campus, Australia
Taxonomy within C. neoformans is
an open question. Based on morphology two anamorph species had originally been
described: C. neoformans and C. gattii. Subsequent mating experiments resulted in the establishment of a new teleomorph
genus: Filobasidiella. New molecular
and epidemiological data have recently established a separate variety for serotype
A isolates, leading to the currently recognised 3 varieties und 5 serotypes. C.n. var. grubii (serotype
A), C.n. var. neoformans (serotype D) and the hybrid serotype AD corresponding to the teleomorph Filobasidiella
neoformans var. neoformans and C.n. var. gattii (serotypes B, C) corresponding to the teleomorph F.
n. var. bacillispora. AFLP and sequencing data have suggested that C.
neoformans var. gattii is sufficiently distinct to be classified as a new species, C.
bacillisporus. Recently C. gattii was proposed
as name for the serotype B and C strains in order to conserve this clinically
relevant name over C. hondurianus and C. bacillisporus. An ever increasing number of molecular studies, e,g,
PCR-fingerprinting with a minisatellite specific primer (M13), AFLP, RFLP analysis
of the orotidine monophosphate pyrophosphorylase (URA5) and phospholipase (PLB1) genes, sequence analysis of a number of genes including
the ITS and IGS regions of the rDNA, mtrRNA, URA5, PLB1 have shown that these varieties belong to diverging phylogenetic
lineages. Furthermore PCR-fingerprinting
has divided more than 1000 global clinical, veterinary and environmental isolates
into 8 molecular types: VNI + VNII = serotype A (var. grubii);
VNIII = serotype AD hybrid; VNIV = serotype D (var. neoformans); VGI, VGII,
VGIII and VGIV = serotypes B and C (var. gattii). AD hybrid isolates (VNIII) revealed two URA5- and PLB1-RFLP
patterns one corresponding to VNI, VNII and VNIV and the other to VNII and
VNIV suggesting different recombination events between var. grubii and var. neoformans leading to diploid or triploid strains, which each having
two or three different copies of the respective genes. The genotypic variation
found between those molecular types lies within a range comparable to that
between established species in other fungal genera, indicating that evolution
and speciation within the cryptococcal complex is an ongoing process.
Phylogenetic placement of orchid mycorrhizal Ceratobasidium from
Australia and Puerto Rico
J. Tupac Otero
CSIRO Plant Industry, Centre
for Plant Biodiversity Research, Australian National Herbarium, GPO
Box 1600,Canberra ACT 2601, Australia
tupac.otero@csiro.au
Ish Sharma
Centre for Plant Biodiversity
Research, GPO Box 1600, Canberra ACT 2601, Australia
ish.sharma@csiro.au
Mark Clements
Centre for Plant Biodiversity
Research, GPO Box 1600, Canberra ACT 2601, Australia
mark.clements@csiro.au
All orchid species depend on mycorrhizal fungi for seed germination. Most
orchid mycorrhizal (OM) fungi are Rhizoctonia-like
fungi, a group of basidiomyces that are classified in several families, and includes
binucleate genus Ceratobasidium and Tulasnella; and multinucleate
genera Thanatephorus and Sebasina. Ceratobasidium is one of the most common OM fungi and has been reported
from Europe, North America, Tropical America and Australia. Ceratobasidium from tropical orchids were placed in four clades, but
the placement of those fungi among the general phylogeny of Ceratobasidium is not yet clear. The primary aim of this study is to
place Ceratobasidium isolates from
Australian and Puerto Rican orchids in the general phylogeny of Ceratobasidium based on ribosomal internal transcribed spacer (ITS). The
phylogeny of the ITS region shows that Ceratobasidium cornigerum,
a species frequently reported as orchid mycorrhizal, is polyphyletic. Three of
the four clades of mycorrhizal Ceratobasidium isolated from the epiphytic Puerto Rican orchids Tolumnia
variegata, Ionopsis utricularioides,
and I. satyrioides are closely
related to Ceratobasidium AGS and Ceratobasidium AGQ, a group of fungi isolated from soil in Japan. One
isolate ffrom the terrestrial Puerto Rican orchid Erythrodes plantaginea was
related to Ceratobasidium AGA. Australian fungi from terrestrial orchids tested
so far (Hymenochilus cygnocephalus and Pterostylis nutans) are
related to Ceratobasidium AGH and Ceratobasidium AGD.
Population ecology
of Amanita muscaria as determined
by random amplified microsatellites (RAMS)
Scott J. Bagley
Department of Botany,
University of Otago, PO Box 56, Dunedin, New Zealand
bagleyscott@hotmail.com
David A. Orlovich
Department of Botany,
University of Otago, PO Box 56, Dunedin, New Zealand
david.orlovich@botany.otago.ac.nz
The ectomycorrhizal fungus Amanita muscaria is a relatively common symbiont of introduced trees throughout
New Zealand, including silver birch (Betula pendula) and Monterey pine (Pinus radiata). It was first recorded in the North Island of New
Zealand in 1934 and the South Island in 1940. However, in 1962, it was
still absent from the lower half of the South Island, where it is now widespread,
indicating that its spread is extremely rapid. The spread is likely to
have co-occurred with the planting of Pinus radiata for
commercial wood production. The potential for A. muscaria to form ectomycorrhizas with Nothofagus, and the rapid spread of the species in the last 45 years,
indicates a potential threat to the native ectomycorrhizal fungi, which are
particularly diverse in Nothofagus forests in New Zealand.
We used genetic fingerprinting to assess population structure
in Amanita muscaria. We studied
an established population of Amanita muscaria in
association with silver birch (Betula pendula)
in a Dunedin park using random amplified microsatellite (RAMS) analysis. We
obtained RAMS profiles using three primers for 108 of the 170 fruit bodies collected. We
scored each band in each profile as either present or absent, and used cluster
analysis to aid in identifying fruit bodies with identical profiles. On
the basis of three identical primer profiles, we determined that there were 28
genetically identical colonies (genets) in an area of 40 x 40 m. The level
of variation detected varied widely between the three primers used. Fingerprint
patterns are likely to be comprised of a mixture of homologous and non-homologous
bands, and we found that some of the individual primer profiles are likely to
reflect population history, while other fingerprint profiles were polyphyletic. In
any given area, detected genet number might increase, and genet size decrease,
with the use of more primers.
Professor Alan Johnson
A preliminary review of the molecular relationships between
Russula and Lactarius and their truffle-like gastroid relatives
J Tonkin
A preliminary review of the molecular relationships between Russula and Lactarius
and their truffle-like gastroid relatives
How different are a pink gilled and a brown capped Amanita at
the microscopic level?
J. McGurk and E. M. DavisonDepartment of Environmental Biology, Curtin University,
GPO Box 1987, Perth, Western Australia 6845
Amanita carneiphylla O.K.
Mill. (subgenus Lepidella, section Lepidella) and A. eucalypti O.K. Mill. (subgenus Lepidella, section Phalloidae) are two distinctive species from Western Australia. A.
carneiphylla has a white cap, volva, ring and stipe and pale pink gills,
while A. eucalypti has
a brown cap, white volva, gills, ring and stipe. How different are they
microscopically? A comparison was made between the microscopic characters
of a fruiting body from six collections of each species which had made over
a number of years. Type material was also examined. Observations
on their micro-morphology were made on cells from the voval cap remnants, cap
pellis, cap margin under-turn, gill margin cells, basidia, basidiospores, subhymenium,
upper and lower side of the ring, stipe pellis, and volva were made for each
fruiting body. Measurements of length and width were made of all of these
cells.
There were distinctive
and consistent differences between these two species in the structure of the
subhymenium, the size and shape of the basidia and the size and shape of the
basidiospores. The cells of the subhymenium, the volval cap remnants,
and the cap pellis showed the greatest difference in Q ratios. Clamp
connections were present in A. carneiphylla but not seen in A. eucalypti.
Discriminant analysis
was conducted using 19 of the 33 variables (L, W, Q ratio) in the dataset. This
confirmed the importance of spores and volval cap remnants in separating the
two species.
Preliminary comparisons
from four Tasmanian vegetation types between vascular plant and macrofungal
communities
Sapphire McMullan-Fisher
Geography and Environment, University
of Tasmania
smcmulla@postoffice.utas.edu.au
Current conservation and management decisions are being considered
for broad vegetation types. However, it is unknown how cryptogam species relate
to communities defined by vascular plants. This project compares vascular plants
(ferns, gymnosperms and angiosperms) with some cryptogams (bryophytes and macrofungi)
to assess community congruence. Four vegetation types were used for community
comparison (wet forest, alpine heath, coastal heath and grassy woodlands) near
Hobart, Tasmania. These were surveyed for macrofungi and vascular plant taxa
from 1999 to 2003. Preliminary presence/absence analysis suggests that many macrofungal
communities show congruence with vascular plant communities. However, the microhabitats,
such as large logs, may have a greater influence on the distribution of some
cryptogamic species than vascular plant species composition. Thus, preliminary
data suggest that broad vegetation types may be a reasonable surrogate for macrofungal
assemblages.
Wood decay fungi
and saproxylic invertebrates in Tasmania's southern forests
Anna JM Hopkins
CRC for Sustainable
Production Forestry, University of Tasmania, Private Bag 12, Hobart 7001
Anna.Hopkins@ffp.csiro.au
Kate Harrison1,2,
Marie Yee1,2, ZiQing Yuan1, Simon Grove3,
Tim Wardlaw3 & Caroline Mohammed1,2,4
1CRC for
Sustainable Production Forestry, 2University of Tasmania, 3Forestry
Tasmania, 4Forestry and Forest Products, CSIRO
Saproxylic communities form a crucial component of the biodiversity
of Tasmania's wet sclerophyll forests. The succession and diversity of these
organisms, particularly of wood decay fungi and associated invertebrates, is
crucial to the formation of habitat features in living trees, including (but
not restricted to) the hollows typical of 'habitat' or 'legacy' trees that are
used by many arboreal mammals and birds. Course woody debris (CWD), such as stags
and large decaying logs on the forest floor, are also an extremely valuable biological
resource, supporting a rich diversity of saproxylic invertebrates and fungi.
A long-term impact of current native forest management in
Tasmania's wet eucalypt forests will be to alter stand age structure across the
managed forest landscape, resulting in the decline of old-growth features. Coarse
wood debris dynamics will also change, resulting in a decline of large diameter
logs. Many studies in the Northern Hemisphere have shown that these are the types
of changes that have had significant negative impacts on saproxylic communities.
As there is a shorter history of intensive native forest management in Australia,
there is still time to reduce any potential ecological impacts. It should be
possible to manage forests to maintain sufficient habitat trees and large diameter
logs to ensure the survival of the saproxylic communities dependent upon them,
through better understanding of saproxylic biodiversity and underlying ecological
processes early in this process of landscape alteration.
This paper describes two ongoing ecological studies of saproxylic
communities. The first examines beetle and fungal diversity associated with large
and small diameter logs on the forest floor; the second looks at fungal and invertebrate
diversity and succession in living trees of different ages.
The number of Australian
macrofungi: an estimate and prospects for documentation
Tom W. MayRoyal Botanic Gardens
Melbourne
Tom.May@rbg.vic.gov.au
Estimates for the number of Australian fungi range as high
as 250,000. Such figures are based on multiplication of the vascular plant diversity,
taking into account host range and specificity, with most of the fungi expected
to be microfungi. At the current rate of progress it may be 1,000 years before
such an enormous diversity is fully catalogued. It is necessary to move from
a perception that the fungal kingdom is the great unknown, to realising that
some groups are less poorly known than others. In setting achievable targets
within reasonable human (and political) timeframes, it seems useful to focus
on key groups, one of which should be the macrofungi. These are the larger fungi,
readily visible to non experts. They are often beautiful or unusual in form and
colour, and of great utility (as mutualists, decomposers and food for native
animals). Larger fungi are also suitable for survey by non-specialists, through
mapping and ecological surveys, and tractable for inclusion in current conservation
initiatives. A catalogue of Australian macrofungi is available in the Fungi
of Australia series, covering in full the basidiomycete macrofungi
such as agarics, puffballs, truffles and coral fungi. For Australian basidiomycete
macrofungi there are currently 3072 accepted species. Recent revisions have added
many new names, but the number of additional taxa is only in the order of two
to four times that already known. Estimates of the true diversity must also consider
the removal of misapplied names and the likely synonymy of old names, known only
from the type, with more recently described taxa. Therefore, a figure of 10,000
Australian basidiomycete macrofungi is proposed. It is suggested that 10 mycologists
(with students) could realistically tackle this diversity over one to two decades,
leading to an Australian macrofungal flora complete enough to be of general utility.
Threatened Fungi - progress
in fungal conservation in New Zealand and
Australia
Peter K. Buchanan
Landcare Research,
New Zealand
buchananp@LandcareResearch.co.nz
Tom W. May
Royal Botanic Gardens Melbourne
Tom.May@rbg.vic.gov.au
The need for conservation of fungi is beginning
to gain recognition in New Zealand and Australia. While the importance of fungi
to biodiversity and to the functioning of healthy ecosystems has been well
documented for decades, only recently has their threatened status been considered
relevant by conservation agencies. The New Zealand Department of Conservation,
for example, now recognises 49 species of fungi under the highest threat category
of 'nationally critical'. In Australia, ten species and one community of fungi
are listed under various legislation at the Federal and State level. Case studies
are presented of several of these threatened species. An assessment is also
made of the number of Australasian fungal species known from very few collections;
this often restricts conclusions about their conservation status. We outline
a series of proposals to enhance effective conservation of Australasian fungi.
Turning up the heat:
heat lethality and its biosecurity implication
G.S. RidleyNew Zealand Forest
Research Institute
geoff.ridley@forestresearch.co.nz
E. Allen and P. Koot
Canadian Forest Service
eallen@pfc.cfs.nrcan.gc.ca
Much of our knowledge of the effect of heat on fungi has centred
on optimum growth rate and substrate sterilisation studies. Little is known about
heat lethality, that is at what temperature do particular fungal species die.
Such information would have high biosecurity value, as it would facilitate the
design of specific heat therapies for non-perishable products capable of carrying
forest pests. It is likely that factors other than
temperature alone contribute to the efficacy of heat therapy such as the physiological
condition and life states of the target organism at the time of treatment. The
effect of desiccation on heat tolerance, and comparison of heat tolerance between
survival structures, such as spores, and actively growing hyphae need to be examined.
A range of species commonly intercepted at the border and pests that are unwanted
in New Zealand have been tested, both in vitro and in
vivo, to determine temperature and duration
required to kill these species. Species tested include Armillaria novaezelandiae, Botryodiplodia
theobromae, Fusarium circinatum, Ophiostoma novo-ulmi, Phellinus weirii, Phlebiopsis gigantea, Phytophthora cinnamomi, Schizophyllum commune, and Sphaeropsis sapinea. Data so far indicates that practical heat therapies can
be developed e.g. heat therapy for treating imported motor vehicles. In vitro testing in a related Canadian study identified lethal
temperatures for both decay and stain fungi including Gloeophyllum sepiarium, Armillaria ostoyae, Heterobasidion
annosum, Phellinus noxius, and Leptographium wageneri.
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