AUSTRALASIAN MYCOLOGICAL SOCIETY CONFERENCE
ABSTRACTS 2001

PAPERS

POSTERS

PAPERS

1. FRESHWATER LIGNICOLOUS FUNGI-FACT, FUNCTION AND FUTURE
Kevin D. Hyde

Centre for Research in Fungal Diversity, Department of Ecology and Biodiversity, The University of Hong Kong, Pokfulam Road, Hong Kong SAR.

Fact: Fungi on submerged wood in streams are a diverse group, comprising taxa from various families. The fungi are mostly relatives of terrestrial taxa and are not a separate taxonomic group. Ascomycetes and their asexual stages are dominant in tropical and subtropical freshwater habitats, while discomycetes are rare. Many ascomycetes particularly in the tropics have appendaged spores, which are ejected from the asci. Fungal communities on submerged wood from tropical, subtropical and temperate streams and lakes appear to be distinct. Highest diversity is found in subtropical streams as this includes temperate and tropical taxa, while the lowest diversity occurs in temperate streams. Still-water bodies such as lakes and ponds also have a lower diversity. Over 1000 lignicolous fungi have been recorded from freshwater habitats.

Function: The main role of lignicolous fungi is in the degradation of dead plant material, especially those containing lignocellulose. Most produce soft rot cavities in wood, most appear capable of digesting cellulose and hemicelluloses, but surprisingly few are capable of degrading lignin.

Future: We are still along way off establishing what factors effect the composition of fungal communities in streams and lakes and carefully designed experiments should be set up to test various parameters. The effects of pollution on such communities is also poorly understood. The use of freshwater fungi as bio-monitors of stream health needs investigation.

2. THE PANDANACEAE-DOES IT HAVE A DIVERSE AND UNIQUE FUNGAL BIOTA?
Eric McKenzie 1, Stephen Whitton 1 & Kevin Hyde 2

1 Landcare Research, Private Bag 92170, Auckland, New Zealand.
2 Centre for Research in Fungal Diversity, Department of Ecology and Biodiversity, University of Hong Kong, Pokfulam Road, Hong Kong.

The Pandanaceae, a predominantly tropical plant family, contains three genera and approximately 900 species-Freycinetia (200 species), Pandanus (600-700 species), Sararanga (two species). A widely cited calculation of world fungal diversity is based on a ratio of six species of fungi for every vascular plant. If this ratio is correct, the Pandanaceae should have about 5,000 species of 'unique' fungi. Approximately 450 species of fungi are known on the family; many are ubiquitous, less fastidious saprobes. The family does not form mycorrhizas, and monocotyledonous plants, in general, support few basidiomycetes. Of 65 mitosporic fungi and 61 ascomycetes recorded on Freycinetia, 32 have been described with Freycinetia as the type substratum and 21 are putatively new to science. Currently, 37 of these are unique to a single species of Freycinetia. Likewise, of 198 mitosporic fungi and 117 ascomycetes recorded on Pandanus, 60 are unique to a single species of Pandanus. Only seven fungi, including one unique species, are known on Sararanga. It is likely that many of the unique species will be found on other Pandanaceae, or host families. In New Zealand there are about 150 fungi recorded on the endemic Freycinetia banksii, although only five species are thought to occur exclusively on this plant. In Hong Kong where two species of Pandanus occur, 45 species of microfungi have been recorded on P. furcatus and 35 on P. tectorius, with 10 species in common. On a world basis 61 species are reported on P. tectorius, only eight of these also occur in Hong Kong. Current knowledge of microfungi on the Pandanaceae is incomplete, and it is impossible to say if the 1:6 ratio of fungi to plants will be proved. However, there is a challenge to find, delimit, and describe the as yet undiscovered fungal treasures associated with the Pandanaceae.

Keywords: Ascomycetes, biodiversity, Freycinetia, mitosporic fungi, Pandanus.

3. NEW ZEALAND SUBANTARCTIC FUNGI
P.R. Johnston

Landcare Research, Private Bag 92170, Auckland, New Zealand.

A recent NSF-funded expedition to the subantarctic Campbell Island, has made this one of the most intensively surveyed areas for fungi in New Zealand. Data will be presented which compares species occurrence and diversity for selected groups of ascomycetes from Campbell Island, the Auckland Islands, Stewart Island and the Chatham Islands, with the mainland South Island. Biogeographic explanations for island biotas often invoke relationships between species diversity and land area, degree of isolation, latitude, and habitat diversity. Patterns of diversity amongst fungi will be compared to those of vascular plants from the same islands.

Keywords: Biogeography, Campbell Island, Auckland Islands, Stewart Island, Chatham Islands.

4. ASPECTS OF THE ECOLOGY OF ARBUSCULAR MYCORRHIZAL FUNGI IN SOILS USED FOR CROPPING
Peter Allan McGee

School of Biological Sciences A12, University of Sydney, N.S.W. 2006, Australia.

Much of our understanding of arbuscular mycorrhizal (AM) fungi has been developed from studying isolates obtained from soils used for cropping. This knowledge has been applied widely to soils despite the clear knowledge that in undisturbed habitats, a different biology may exist. This became important when studying soils in which structure had declined to the point where inoculation with AM fungi became an economically viable option for remediation. The fungi from one cropping soil were found to grow rapidly down the root system, which is common. However, the fungi lacked spread into the soil phase. Secondly, the fungi formed blastospores rapidly. Thus fungal energy appears to be directed towards rapid formation of reproductive units and immediate acquisition of energy, an 'r' life history strategy. In contrast, AM fungi from undisturbed habitats spread away from roots immediately and form reproductive units slowly. The widespread research of fungi that have 'r' life history strategies has implications for developing our understanding of the function of AM fungi environments with lower levels of disturbance. Indeed, use of research must be tempered by our understanding of the applicability of the strategies of those fungi.

5. MONITORING THE SPREAD AND IMPACT OF ENTYLOMA AGERATINAE, A WHITE SMUT FUNGUS INTRODUCED TO NEW ZEALAND FOR THE BIOLOGICAL CONTROL OF MIST FLOWER (AGERATINA RIPARIA)
J. Fröhlich & A.F. Gianotti

Landcare Research, Private Bag 92170, Auckland, New Zealand.

Entyloma ageratinae (Ustiginales: Basidiomycotina) was released in New Zealand in November 1998 as a biological control agent for the environmental weed mist flower (Ageratina riparia: Asteraceae). Since then the fungus has established and quickly spread (up to 92 km in two years). At eight of the nine sites where the fungus was released, monitoring 13-14 months after introduction revealed that (1) mist flower plants had suffered on average 40% defoliation; (2) the weed had responded with strong regrowth (regrowth at c. 40% of nodes); and, (3) about half of the regrowth was infected with the fungus. Further monitoring about two years after release recorded less defoliation (27.4%) and regrowth (27.6%), but a similar level of infection on regrowth (53.3%). Successive defoliation and regrowth events should be costly for the plant, and we expect that the ability of mist flower to recover from leaf-loss will decrease with time. As well as the impacts of E. ageratinae on mist flower, we are interested in the 'flow-on' effects of biological control on the surrounding vegetation. If, as we anticipate, mist flower cover gradually declines, will the native plant community revert to what it was before the weed invaded? To address this question, species were identified and plants counted in vegetation plots, half with and half without mist flower, in the summers of 1999/2000 and 2000/2001. In both years, significantly more native plant species were found in plots without mist flower, than in plots with the weed. During the year between assessments, mist flower cover decreased significantly (by c. 25%) within the study plots. Over the same period, native plant diversity significantly increased in plots containing mist flower, while it remained stable in plots without the weed. Measurements will continue annually and we hope to see further recovery in native species diversity.

6. THE MYCOFLORA OF EUCALYPTUS IN NEW ZEALAND
G.S. Ridley & M.A. Dick

New Zealand Forest Research Institute, Private Bag 3020, Rotorua, New Zealand.

Eucalyptus species form a significant component of New Zealand's urban and rural landscape as both amenity and plantation trees, although no members of the genus are native. Since the official beginning of European colonization of New Zealand in 1850 some 180 species of Eucalyptus have been introduced. Of these, 19 species have become fully naturalised, that is established as self-maintaining populations in the wild. A further seven are considered to be casuals, that is either found only infrequently in the wild or present in the wild in close proximity to parental trees in cultivation. Although lists of pathogens have been published there has not been any attempt to document or assess all the records of fungi associated with eucalypts in New Zealand. This report is a first attempt to do so.

7. THE GENUS INONOTUS (HYMENOCHAETALES) IN AUSTRALIA
J. A. Simpson

Research and Development Division, State Forests of N.S.W., P.O. Box 100, Beecroft 2119.

The Hymenochaetales comprises Holobasidiomycetidae with basidiomata resupinate to pileate, annual or perennial, typically lignicolous and causing white rots, monomitic or dimitic, lacking clamp connections, and often with hymenial setae. The genus Inonotus P. Karst. has been used in recent years for species of Hymenochaetales with poroid, stipitate or sessile, monomitic and usually rather soft, annual basidiomata. In Australia, as elsewhere, the genus includes a number of economically important root, butt and heart rot fungi. The circumscription of the genus has in practice been confused with no consensus between workers. The delimitation from Aurificaria D.A. Reid, Coltricia S.F. Gray, Cyclomyces Fr., Phaeolus (Pat.) Pat. and Phellinus Quél. for example has been in dispute. The Australian taxa of Inonotus will be reviewed and generic limits discussed.

Keywords: Inonotus, Australia.

8. CRYPTOCOCCUS NEOFORMANS: GLOBAL MOLECULAR EPIDEMIOLOGY
Wieland Meyer

Molecular Mycology Laboratory, Centre for Infectious Diseases and Microbiology, The University of Sydney at Westmead Hospital, Westmead, N.S.W., Australia.

Cryptococcus neoformans is a basidiomycetous yeast with three suggested varieties: var. grubii (serotype A), var. neoformans (serotype D) and var. gattii (serotypes B and C). Varieties grubii/neoformans infect immunocompromised patients while variety gattii mainly infects immunocompetent hosts. The global genetic distribution of C. neoformans was studied by PCR-fingerprinting with single primers specific to minisatellite or microsatellite DNA. Clinical/environmental isolates obtained from around the world grouped into eight major molecular types (VNI and VNII = serotype A, VNIII = serotype A/D, VNIV = serotype D and VGI, VGII, VGIII and VGIV = serotypes B and C). VNI and VGI were the most common genotypes. VGIII was geographically restricted to India/U.S.A. and VGIV to India/South Africa. Unique, strain-specific patterns were found for most of the U.S. isolates, indicating a high degree of genetic diversity compared with isolates obtained from other areas in the world. Non-U.S. isolates were highly genetically homogeneous or even clonal. When analysed with GelComparII the strains clustered broadly according to their country of isolation. Some strains were common to different countries. The overall global similarity between strains was 60 per cent. Our findings support a division of C. neoformans into three varieties or even three separate species. Isolates obtained from the same patient at different time points and different body sites had identical banding patterns indicating a single source of infection. Regional profiles of eucalypt-derived and clinical isolates were concordant, supporting an epidemiological association between these trees and human infection. An automation of the methodology is currently underway.

Keywords: Cryptococcus neoformans, global molecular epidemiology, PCR-fingerprinting.

9. MOLECULAR TYPING OF LATIN AMERICAN/SPANISH CRYPTOCOCCUS NEOFORMANS ISOLATES AS PART OF THE GLOBAL EPIDEMIOLOGY SURVEY
Alexandra Castaneda^{1, 2} Elizabeth Castaneda ² & Wieland Meyer ¹

1 Centre for Infectious Diseases and Microbiology, Molecular Mycology Laboratory, The University of Sydney, Department of Medicine at Westmead Hospital, ICPMR, Level 3, Room 3114A, Darcy Road, Westmead, N.S.W. 2145, Australia.
2 Grupo de Microbiologia, Instituto Nacional de Salud, Avenida Eldorado, carrera 50 Bogota, Colombia.

Cryptococcus neoformans, the etiological agent of cryptococcosis, is a heterobasidiomycetous yeast. It has been subdivided into three varieties: C. neoformans var. grubii (serotype A), var. neoformans (serotype D), and C. neoformans var. gattii (serotypes B and C). The serotype AD isolates seem to be genetic hybrids between the serotype A and D. Human infection is acquired by the inhalation of infectious propagules (basidiospores or yeast cells) from the environment. It primarily affects the lung and the central nervous system. The yeast form of var. neoformans has been isolated worldwide from soil contaminated with avian excreta and more recently, certain trees have been proposed as environmental habitat. In contrast var. gattii is geographically restricted to tropical and subtropical regions. To date, specific host trees have included eucalypt and almond trees. Several molecular typing methods have been applied to the epidemiology of C. neoformans isolates, these include DNA sequencing, karyotyping, random amplification of polymorphic DNA (RAPD), DNA hybridisation, amplified fragment length polymorphism (AFLP) and PCR-fingerprinting. The aim of this study was to investigate the Latin American/Spanish genotypes and to incorporate these data in the global epidemiological database of C. neoformans. More than 700 clinical and environmental cryptococcal isolates from Argentina, Brazil, Chile, Colombia, Guatemala, Mexico, Peru, Spain and Venezuela have been analysed by PCR-fingerprinting using single primers, specific to minisatellite (core sequence of the wild-type phage M13 (5' GAGGGTGGCGGTTCT 3')) and to microsatellite (GACA)4 sequences. The results of this study have permitted the determination of the genotypes and their distribution within each participating country and to study the relationship between clinical and environmental isolates. Serial isolates have been investigated to answer the question if a single patient is infected by one or more strains and also if a recurrent infection is caused by the same or a new strain.

Keywords: Cryptococcus neoformans, molecular epidemiology, Polymerase chain reaction fingerprinting.

10. ARE RHIZOMORPHS OF ARMILLARIA LUTEOBUBALINA ORGANS OF TRANSLOCATION OR ABSORPTION?
Mamta Pareek, Louise Cole & Anne E. Ashford

Mycorrhizal Research Group, School of Biological Sciences, University of New South Wales, Sydney 2052, Australia.

Armillaria luteobubalina is one of the most serious pathogens in Australian ecosystems causing much damage particularly in dry sclerophyll eucalypt forests. Armillaria luteobubalina produces rhizomorphs like other Armillaria species but at many sites they do not to travel for long distances in soil, and disease spread is caused by mycelial systems via root contact. The aim of this research was to compare the growth rate and structure of A. luteobubalina rhizomorphs grown aerially and submerged on agar and in liquid culture, using light and scanning electron microscopy. They differed in growth rate, amount of mucilage, extent of peripheral hyphae, degree of pigmentation and in the structure of inner cortex; otherwise they had similar internal structure comprising 4 radial zones, namely, peripheral hyphae, outer cortex, inner cortex and medulla. The central medullary space appeared to be a gas-filled cavity and the zone of inflated hyphae interspersed with narrow hyphae which developed at the interface between inner cortex and medulla resembled higher plant aerenchyma. There was no evidence of translocatory hyphae such as vessel hyphae. A vital probe DFFDA accumulated in the vacuoles of peripheral hyphae suggesting they are permeable. The data support the view that these rhizomorphs are adapted to survive anaerobiosis and in moist conditions they can function as organs of absorption and play a role in nutrient uptake.

Keywords: Armillaria luteobubalina, rhizomorph, DFFDA.

11. EXTRACELLULAR PROTEOLYTIC AND LIPOLYTIC ACTIVITY OF UBIQUITOUS MARINE FUNGI
Sarah Morrison-Gardiner

Australian Institute of Marine Science, P.M.B. 3, Townsville Mail Centre, Townsville, Qld 4810, Australia.

Naturally produced enzymes, particularly those secreted by many bacteria and fungi are becoming more important in biotechnology, particularly if they are operational at extremes of salinity, pH or temperature. By their nature, fungi contribute to the decomposition of marine substrata in order to survive, and therefore they must have the ability to produce exoenzymes that would convert complex substrata into a form easily utilised for nutrition. A total of 100 ubiquitous marine fungi collected from sites offshore the Australian coast were identified to genera, and screened for active proteases and lipases. Genera included multiple representatives of Aspergillus spp. (25), Penicillium spp. (23), Cladosporium spp. (8), Alternaria spp. (5), Fusarium spp. (2), Mucor spp. (2), and Torpedospora spp. (2). Eleven isolates could not be identified (NID) while 23 produced sterile mycelia. The remaining 13 samples were representatives of single genera. All isolates were screened for extracellular proteolytic and lipolytic activity on selective agar and in a 96-well plate assay. Selective agar proved more sensitive to proteolytic activity, with 85 per cent of the fungi showing evidence of proteolytic activity, compared with only 18 per cent showing lipolytic activity. Screening of 15 isolates in a 96-well plate bioassay found a higher sensitivity to lipases, and less sensitivity to proteases. Four isolates showing high proteolytic/lipolytic activity were screened at 4°C, 27°C, 37°C, 45°C and 55°C. Acremonium sp.85 and Oidiodenron sp.1218 were found to have proteases active at 55°C, while Aspergillus sp.53 and NID1308 produce lipases active at 4°C. Results of this study indicate that screening of fermentation cultures using microplate assay is highly quantitative and specific. Commercially it is also advantageous, as the active enzyme may be easier to culture and separate than one active in solid phase fermentation processes only.

Keywords: Marine fungi, enzymes, protease, lipase.

12. OCCURRENCE OF TRITERPENOIDS AND POLYSACCRARIDES ON GANODERMA TROPICUM WITH GANODERMA LUCIDUM AS A REFERENCE
Nyoman P. Aryantha ¹ Andi Adinda ² & Suswini Kusmaningati ²

1 Dept. of Biology ITB, Jalan Ganesha 10 Bandung 40132, Indonesia.
2 IURC Life Sciences ITB, Jalan Ganesha 10 Bandung 40132, Indonesia.

A local strain of Ganoderma tropicum has been analyzed for the appearance of triterpenoids and polysaccharides with a commercial Ganoderma lucidum as a reference. Ganoderma tropicum was isolated from a Delonix regia tree, an ornamental tree locally known as Flamboyant, on December 1999. The fungus is quite an aggressive parasite killing the tree within 1-5 years. The fruiting bodies of both G. tropicum and G. lucidum were obtained by growing them in sawdust after a 3 month incubation. Analysis for triterpenoids was conducted by using silica gel-thin layer chromatography (TLC) with eluent of chloroform:methanol (10:1) and Carr-Price as well as Lieberman-Burchard as banding agents and observed under UV light (l366 nm). The same technique, except for the eluent n-buthanol:acetic acid:eter:water (9:6:3:1) and banding agent of aniline ftalate, was also used for detecting polysaccharides in the form of their monomers (glucose, galactose, xylose and rhamnose) under normal light. Both triterpenoids and polysaccharides were detected on G. tropicum and G. lucidum, indicating that the local strain of G. tropicum also possesses medicinal value.

Keywords: Ganoderma tropicum, Ganoderma lucidum, triterpenoids, polysaccharides, medicinal mushroom.

13. RESEARCH AT HERBARIUM BRIP
Roger Graham Shivas

Plant Pathology Herbarium (BRIP), Department of Primary Industries, 80 Meiers Road, Indooroopilly, Qld 4068, Australia.

The Queensland Department of Primary Industries Plant Pathology Herbarium (BRIP) houses about 40,000 specimens, mostly plant pathogenic microfungi. Two mycologists and five part-time technical staff maintain the collection. The mycologists comprise a full-time curator, Dr Roger Shivas, and a part-time post-retirement associate, Dr Sivanesan, formerly of the International Mycological Institute. The former and now retired curator of the collection, Dr John Alcorn, continues his mycological studies at BRIP. The technical staff have responsibilities for the care of the herbarium specimens and associated living culture collection as well as update of the specimen collection database.

BRIP provides support for the Cooperative Research Centre for Tropical Plant Protection through a project which aims to amalgamate collections of tropical plant pathogens in Australia; produce a unified database and catalogue of plant pathogenic fungi in northern Australia and establish a collection of DNA of important exotic and endemic pathogens. It is anticipated that the BRIP database will eventually be available on the Web in a modified form.

BRIP provides support for the Australian Quarantine and Inspection Service in the form of pest risk analyses and information regarding the status (presence and distribution) of plant pathogenic microfungi in Queensland. This information is critical in meeting phytosanitary and market access requirements of trading partners. Recently some BRIP staff developed and ran a training course in plant health for agricultural officers in Irian Jaya, Indonesia.

Taxonomic research at BRIP has centred on Dr Sivanesan's studies of Australian ascomycetes and Dr Kálmán Vánky's studies of Australian Ustilaginomycetes. These on-going studies have resulted in the discovery and description of several new taxa.

Keywords: BRIP, ascomycetes, Ustilaginomycetes.

14. A PRELIMINARY STUDY OF THE DISTRIBUTION OF PROTEACEAE FOLIAR PATHOGENS
J.E. Taylor ¹ & P.W. Crous ²

1 Department of Biological Sciences, University of Botswana, Private Bag UB0022, Gaborone, Botswana.
2 Department of Plant Pathology, University of Stellenbosch, Private Bag X1, Stellenbosch 7602, South Africa.

The Proteaceae are distributed predominantly in the Southern Hemisphere occurring in Australia and the South Pacific, the Americas including Mexico, Central and South America, Africa, India and South East Asia. The centres of diversity of this family are Southern Africa and particularly Australia. Proteaceae are becoming important in the cut-flower industry and in horticulture, and therefore research is developing in the study of their pathogens. The pathogens, and most notably the foliicolous pathogens, tend to be unique to these Proteaceae hosts. However, it appears that pathogens associated with Proteaceae in the various regions where members of the family occurs differ, and it is possible that the divisions in the family are reflected in the host and geographic range of the foliar pathogens. In this study an attempt is made to investigate this observation, and although much research has been carried out verifying herbarium specimens in South Africa, the same cannot be said in Australia and South America. Research has been carried out on Phyllachora with species recorded on Proteaceae in Australia and unverified accounts in South America (where all of the Proteaceae genera are in the subfamily Grevilleoideae). In addition epiphytic and biotrophic taxa have been recorded from these regions, such as species of Meliolales, and members of the family Asterinaceae and unverified accounts of species in Microthyriaceae, Schizothyriaceae, Parodiopsidaceae and Chaetothyriaceae. These have been recorded in Australia, Asia and South America, but none have been recorded in South Africa. South Africa and Australia share some proteaceous fungal taxa such as Vizella interrupta and Verrucisporota proteacearum, and species of Clasterosporium and Cercostigmina. By reinvestigating herbarium specimens and collecting Proteaceae pathogens in all regions it may be possible to demonstrate an interesting example of fungal biogeography.

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POSTERS

1. PUFFBALLS IN ARID SOUTH AUSTRALIA
Pam Catcheside ^1,2 & David Catcheside ²

1 Plant Biodiversity Centre, Hackney Road, Hackney, S.A. 5069.
2 Flinders University, School of Biological Sciences, P.O. Box 2100, Adelaide, S.A. 5001.

In the drier sandy parts of South Australia, puffballs predominate amongst the epigeous fungi. This may represent adaptations to the dry environment. The more or less spherical puffball presents a reduced surface area to volume ratio compared with that of an agaric mushroom, a factor expected to reduce the rate of water loss. Puffballs have a range of ways of releasing their spores. In many, the spore case is raised on a stipe or by the bending back of the exoperidium (outer casing). In Tulostomas, small to medium-sized stalked puffballs (6-24 mm diameter), the stipe is usually buried with only the peridium exposed. In a number of species, including T. readerii, the exoperidium, with sand particles adhering, forms a collar at the base of the endoperidium (inner casing), helping to keep the puffball upright if the stipe rots or the peridium becomes detached.

The spores of Schizostoma laceratum, a rare stalked puffball, are released by the opening of the peridium into a number of irregular lobes. The peridium of the stilt puffball, Battarraea stevenii, has a dome-shaped lid which falls off to expose the spore mass. The exoperidium of Podaxis pistillaris falls away like a cast off eggshell. The spores of Chlamydopus meyenianus are released through a wide apical gash in the puffball, elevated on a broad, vertically channelled stipe. In these three larger stalked puffballs the spore mass is copious and adheres to all surfaces it contacts. In Geastrum, Earthstars, the exoperidium splits into a number of stellate rays. These form a base under the endoperidium which keeps the fruit body upright. The exoperidium of G. fornicatum splits transversely forming a hollow, windowed egg, thus raising the endoperidium with its spore mass.

2. BASIDIOMYCETES ISOLATED FROM ESCA-LIKE HEART ROTS OF GRAPEVINES IN AUSTRALIA
Jacqueline Edwards ^1,2 Ian Pascoe ^1,2 Natalie Laukart ^1,2 James Cunnington ² & Michael Fischer ³

1 CRC for Viticulture, P.O. Box 154, Glen Osmond, S.A. 5064.
2 Agriculture Victoria - Knoxfield, Private Bag 15, Scoresby Business Centre, Vic. 3176.
3 Institut fur Botanik, Universitat Regensburg, D-93040 Regensburg, Germany.

Esca is one of the most destructive diseases of grapevines in Europe, reducing both productivity and longevity of the vines. When the trunk of an esca-affected vine is cut open, the internal symptom is a soft white heart rot bordered by black necrotic wood. At least two pathogens are thought to be associated with esca: a mitosporic fungus, Phaeomoniella chlamydospora, responsible for the black necrosis and a basidiomycete, Fomitiporia punctata, responsible for the white heart rot. Certainly, F. punctata is the predominant basidiomycete isolated from white heart rot of grapevines in parts of Europe such as Italy, but there have also been reports of other basidiomycetes, such as Phellinus ignarius and Stereum hirsutum, associated with esca-like heart rots. Over the past two years, we have isolated at least five different basidiomycete species from esca-like heart rots of grapevines in Australia, and have found several basidiocarps on vines in the field. At this stage, it is thought that one of the basidiomycetes is F. punctata, but the others are possibly Inonotus spp., perhaps unique to Australia. Further morphological examination and DNA sequencing is underway in order to confirm the identity of these fungi associated with white heart rot of grapevines in Australia.

Keywords: Esca, Fomitiporia punctata, Inonotus spp., white heart rot.

3. PHYSIOLOGICAL RESPONSES OF THREE FUSARIUM SPECIES TO ENVIRONMENTAL WATER STRESS
Sandrine Makiela & Keith M. Harrower

School of Biological & Environmental Sciences, Central Queensland University, Rockhampton, Qld 4702.

A recent study was undertaken investigating the effect of physiological water stress on resource partitioning in three Fusarium species. The main emphasis of this study was on growth dynamics and the partitioning of resources into the various conidial types produced. It was shown that as water stress increases, resources are partitioned away from linear growth and the production of the meso- and macroconidia, and was partitioned towards branching and the production of microconidia. Microconidia were also found to be more resistant to desiccation than other spore types. The significance of these findings for the ecology of these fungi is discussed.

4. VICTORIA'S PLANT PEST AND DISEASE REFERENCE COLLECTIONS
Catriona J. Moors, Linda Semeraro, James H. Cunnington, Kyla J. Finlay, Kerry L. Thomas, Mali B. Malipatil, Ian G. Pascoe

Institute for Horticultural Development, Private Bag 15, Scoresby Business Centre, Vic. 3176.

The Institute for Horticultural Development-Knoxfield holds the most comprehensive reference collections of plant pests and diseases in Victoria. The two collections are the Plant Disease Herbarium (VPRI), comprising specimens of fungi, bacteria, nematodes, viruses and phytoplasmas; and the Victorian Agricultural Insect Collection (VAIC), comprising specimens of both beneficial and pest insects and arachnids. Agricultural pests and diseases predominate, but the collections also contain pests and diseases of weeds and native plants. Both collections are of historical significance, established in the late 1800s by Daniel McAlpine and Charles French, pioneers in Australian plant pathology and entomology. These collections together contain approximately 100,000 specimens. The VAIC consists of 80,000 specimens, pinned, stored in alcohol or mounted on microscope slides. The collection also includes photographic and digital images. Herbarium VPRI consists of 22,500 specimens, mostly dried or pressed symptomatic plant material, but also including microscope slides, living cultures, dried cultures, photographs, digital images and notes. There are 2000 living cultures of fungal and bacterial pathogens. The collection databases are currently being upgraded. As the records are verified and the database edited, the information will be made available to a web page. The plant disease herbarium is also part of the National Collection of Fungi, which comprises the plant disease herbaria of Victoria, New South Wales and Queensland. The collections represent a tangible record of the pests and diseases present in Victoria, as required by the World Trade Organisation, and are often referred to by Plant Standards and the Australian Quarantine and Inspection Service. They also serve as reference specimens for diagnostic services and are a valuable resource for scientists involved in plant health and integrated pest management research. Specimens are available for conditional loan and database information useful for research projects may also be requested.

Keywords: Herbarium, plant diseases, plant pests, databases, Victoria.

5. FUNGI OF THE FOREST GIANTS: FRIEND OR FOE?
Felicity Adams ^1,2 Mike Webb ¹, Warren Shipton ² & Paul Reddell ³

1 CSIRO Land and Water, P.M.B. Aitkenvale, Qld 4814.
2 James Cook University, Douglas, Qld 4811.
3 CSIRO Land and Water, P.O. Box 780, Atherton, Qld 4883.

Eucalyptus grandis, the forest giant, dominates wet sclerophyll forests that fringe tropical rainforest in north-eastern Australia. Plants in these forests rely on specialized root-fungus structures 'mycorrhizae' for nutrient absorption. Mycorrhizae involve the exchange of soil nutrients, especially phosphorus, absorbed by the fungal mycelium, for carbohydrates inside the plant root. Interestingly, rainforests are typically arbuscular mycorrhizal, whereas eucalypts are predominantly ectomycorrhizal but may sometimes form arbuscular mycorrhizae. These two mycorrhizal types involve different fungal partners and structures, but it is not well understood whether both are beneficial for eucalypt growth. The occurrence and relative growth effects of arbuscular mycorrhizae and ectomycorrhizae on E. grandis were investigated in this PhD research. Collection of E. grandis roots from various native forests (29 sites in total) demonstrated that adult E. grandis trees were invariably heavily ectomycorrhizal, whereas seedlings had up to half their root length colonized by arbuscular mycorrhizal fungi and variable levels of ectomycorrhizae. Surprisingly, arbuscular mycorrhizal fungi caused rapid, persistent, and often severe growth depressions of E. grandis seedlings in glasshouse pot experiments conducted using a range of different treatments, despite typically low colonization levels (<5% root length colonized). Growth depressions were particularly evident at low soil phosphorus and under high light conditions. Ectomycorrhizal fungi, in contrast, generally increased growth and phosphorus absorption of E. grandis seedlings. The results demonstrate that formation of arbuscular mycorrhizae on E. grandis does not necessarily indicate beneficial function, and challenges our understanding of the role of arbuscular mycorrhizae and ectomycorrhizae in the ecology and dynamics of tropical eucalypt forests.

Keywords: Eucalyptus, arbuscular mycorrhizae, ectomycorrhizae, growth, phosphorus.

6. PARTICLE FILTRATION-A POSSIBLE METHOD FOR THE RAPID ASSESSMENT OF MICROFUNGAL DIVERSITY IN RAINFOREST LEAF LITTER
Barbara Paulus

James Cook University, Smithfield, Qld 4878.

Traditionally, fungi have been studied by observation of fruiting bodies on substrata. For some substrata, indirect methods have also been employed. These include the addition of a substratum, such as soil suspension or leaf particles, to a medium and the isolation of fungal cultures from outgrowing vegetative hyphae. The particle filtration technique is one of a range of indirect methods and has been tested as a quick method of enumerating fungi on leaf litter substrata. For biodiversity estimates to be reliable, the methodology needs to be tested and standardised. As part of a pilot study, the effects of surface sterilisation and of storage of leaf litter on the recovery of fungal isolates have been investigated. A sampling design has been suggested and an example of the application of this method to a simple ecological question is provided.

7. MYXOMYCETES ASSOCIATED WITH SNOWBANKS IN ALPINE AREAS OF NEW ZEALAND
Steven L. Stephenson ¹ & Peter R. Johnston ²

1 Dept. of Biology, Fairmont State College, Fairmont, West Virginia 26554, U.S.A.
2 Landcare Research, Private Bag 92170, Auckland, New Zealand.

A distinctive ecological group of myxomycetes (plasmodial slime molds) is associated with the melting snowbanks that occur during late spring and early summer in alpine regions of the temperate zone. The species that occupy this rather special and very limited microhabitat are usually referred to as 'snowbank' myxomycetes, since they produce fruiting bodies only during the relatively brief period of time when the special microenvironmental conditions associated with melting snowbanks and apparently required for their growth and fruiting exist. Most species in such genera as Lamproderma and Lepidoderma apparently occur only in snowbank microhabitats. During the period mid-November to mid-December 2000, visits were made to a number of localities in the mountains of New Zealand where snowbank myxomycetes might be expected to occur. Eight different localities, all located between 42° and 45°S latitude in the Southern Alps on South Island, yielded a total of more than 175 collections. This is the largest series of collections of snowbank myxomycetes known for any region in the entire Southern Hemisphere. Because the treeline in New Zealand mountains is relatively low and usually does not extend into the alpine habitats where snowbanks occur, the species of snowbank myxomycetes typically associated with coarse woody debris were not represented among the specimens we collected. (Supported by a grant from the National Science Foundation of the United States.)

Keywords: Ecology, myxomycetes, New Zealand, snowbanks.

8. Communities or Plantations? Microbes and site restoration
P.R. Johnston

Landcare Research, Private Bag 92170, Auckland, New Zealand.

The tea-tree species manuka (Leptospermum scoparium) and kanuka (Kunzea ericoides) are important colonisers of disturbed habitats, and many site restoration projects in New Zealand use nursery-raised seedlings as pioneer species. Typically, seeds are locally sourced, with the seedlings then being raised in nurseries in commercial potting mixes, under high nutrient and watering regimes. In a pilot scale study, two functional groups of fungi (ectomycorrhizal mushrooms and leaf endophytes) were sampled from stands of manuka at both natural and restored sites. Stands of tea-tree established in restoration projects appear to lack much of their natural microbial diversity, the microbial communities being dominated by widespread, weedy generalists. This lack of microbial diversity may have a flow-on effect to other members of the community, such as the invertebrates that feed on the fungi, and the birds that feed on the invertebrates. As yet, we do not know if the diversity in planted stands will increase and become more 'natural' as the stands age. Perhaps the early establishment of highly modified microbial communities will buffer the stands to resist establishment by the diverse group of species normally found within them. Are current methods leading to the establishment of tea-tree plantations rather than tea-tree communities?

Keywords: Kunzea, Leptospermum, fungal endophytes, ectomycorrhizae.

9. RAINFOREST FUNGI OF TROPICAL NORTH QUEENSLAND
Paul Zborowski ¹ & Ceridwen Pearce ²

1 Close-Up Photo Library.
2 Australian Tropical Mycology Research Centre Ltd, P.O. Box 312, Kuranda, Qld 4872, Australia.

The fungi of tropical north Queensland rainforests are relatively understudied, and yet they are a colourful and vital component of the rainforest floor. This poster illustrates a tiny fraction of the fungal diversity found on wood, and in soil and leaf litter in the rainforests around Cairns. Wood decay fungi illustrated include the conspicuous discomycete, Peziza coccinea, the brightly coloured jelly fungus Tremella mesenterica, and bracket fungi such as Stereum spp., Schizophyllum commune, a common gilled fungus, and oddities such as Cymatoderma elegans, and bioluminescent fungi growing on wood, are also illustrated. In contrast, common fungi growing on rainforest soil and leaf litter include coral fungi; Calocera sinensis and Ramaria sp., and gilled fungi such as Entoloma sp., Hygrocybe sp. ?miniata, Lepiota sp., Macrolepiota konradii, Marasmius elegans and Marasmius sp. Hygrocybe sp. ?miniata produce small, startling red fruiting bodies on the rainforest floor. The mushroom caps sometimes provide shelter for tiny rainforest arthropods. Also on the rainforest floor, the striking but delicate fruiting bodies of Dictyophora utilise a putrid aroma to attract flies, which in turn, aid in dispersal of the sticky spores of the fungus.

10. AUSTRALIAN TROPICAL MYCOLOGY RESEARCH CENTRE LTD
Ceridwen A. Pearce ¹ & K.D. Hyde ²

1 Australian Tropical Mycology Research Centre Ltd, P.O. Box 312, Kuranda, Qld 4872, Australia.
2 Centre for Fungal Diversity, Department Ecology and Biodiversity, The University of Hong Kong, SAR China.

The Australian Tropical Mycology Research Centre Ltd (ATMRC) has been established by an Australian company, which aims to increase understanding of mycology in the Australian tropics by fostering high quality scientific research. The ATMRC supports research into all aspects of fungal biology including taxonomy, ecology, physiology and genetics. We are an independent facility which encourages collaboration with other research and educational institutes throughout Australia and overseas.

The ATMRC is a non-profit company, therefore all revenue raised is reinvested with the aim of achieving our mission statement: supporting research into Australian tropical fungal biology. Current research projects include: a biodiversity survey of fungal saprobes on fallen decayed twigs and logs in Type 1b rainforest of the Atherton Tableland; examination and identification of fungi from senescent tree fern and birds nest fern leaves and fronds using direct and indirect methods; and, a biodiversity survey of fungi from native Australian animal dung.

Collaborative projects include an examination of mycetozoans associated with litter microhabitats in tropical forests of northern Queensland, and support of a PhD student at James Cook University examining methods of biodiversity assessment of microfungi in tropical rainforest leaf litter.

The ATMRC is also involved in the discovery and development of natural resources such as tropical rainforest fungi, for use in biotechnology, including the search for pharmaceutically novel compounds.

The ATMRC is presently based near the rainforest village of Kuranda, c. 37 km west of Cairns. The Centre has been set up in an established house on 5 acres of land, with mixed tropical fruit trees and rainforest. We also have access to a further 77 acres of rainforest at Butcher's Creek on the Atherton Tableland, just behind the tallest mountain in Queensland, Mt. Bartle Frere. Persons interested in collaborating or using the facilities should contact Ceri at ATMRC, P.O. Box 312, Kuranda, Qld 4872, phone (07) 40930096 or email cpearce@tpgi.com.au.

11. THE GROWTH CHARACTERISTICS OF AN AUSTRALIAN STRAIN OF GRIFOLA
Peter Wenzel, Kirsten Schliephake & Greg Lonergan

Centre for Applied Colloid and BioColloid Science, Swinburne University of Technology, P.O. Box 218, Hawthorn, Victoria, Australia, 3122.

For hundreds of years, the 'maitake' mushroom (Grifola frondosa), has been known throughout China and Japan as an important culinary and medicinal fungus. It has traditionally been held in high regard as a broadly acting healing agent. This mushroom is cultivated in a number of countries around the world and the potential medicinal uses for maitake are well documented. Clinical trials suggest that the maitake mushroom has the ability to enhance the function of the immune system. It is used to combat a variety of conditions including cancer, HIV, high cholesterol, chemotherapy side affects, and high blood pressure1, 2.

While Grifola frondosa has a number of applications, other species in this genus have received relatively little attention. A strain of Grifola was recently isolated from forest in Australia. Microscopic characteristics were observed and recorded. Both this strain and a known Grifola frondosa strain were cultured on PDA to determine general growth characteristics over a range of pH and temperature conditions. The two strains were also compared in their laccase activity after culturing on MEB.

This data will facilitate investigation of fruit body cultivation on a variety of substrata. The effect of substratum composition and cultural parameters on polysaccharide production will also be investigated.

12. VARIATION OF PHYTOPHTHORA PALMIVORA, CAUSAL ORGANISM OF ROOT AND FRUIT ROT OF DURIAN
Somsiri Sangchote & Ratiya Pongpisutta

Department of Plant Pathology, Kasetsart University, Bangkok-10900, Thailand.

Twenty-six isolates of Phytophthora palmivora were obtained from diseased leaves, branches, stem and soil from different locations in the east and south of Thailand. Morphological characteristics of asexual structures, presence or absence of chlamydospores, and maximal growth temperature, and colony type were considered as characteristics for identification. Sporangia were variable in shape (such as ovoid, ellipsoid, obpyriform, ovoid-obpyriform, and spherical). Sporangia were caducous, with a short pedicel (2.8-4.2 mm), and conspicuously papillate and variable in size (an average 35 to 90 mm in length and 22 to 62 mm in breadth with a length:breadth ratio of 1.6:2.0). Sporangia are also variable in shape, depending on the isolate, mostly elliptical to ovoid, and prominently papillate. All isolates grown on carrot agar at 25°C after 7 days of incubation, had diameters of growth measuring 9 cm. At the maximum temperature (about 35°C), growth diameters were 8-9 cm except isolate P14 which couldn't grow. Colonies on potato dextrose agar mostly had a stellate growth pattern except P09, P27, P31, and P33 which had radiate, irregular and a bit fluffy, slight petallate, and stoloniferous growth, respectively. These Phytophthora palmivora isolates infected the wounded leaves of durian, pepper and rubber successfully. The severity of isolates of P. palmivora was different.

13. OOMYCETE TUBULAR VACUOLES
William G. Allaway & Osu Lilje

School of Biological Sciences, The University of Sydney, N.S.W. 2006, Australia.

The tip region of oomycete hyphae contains a network of fine, slow-moving tubular structures which have been identified as tubular vacuoles by their ability to accumulate and retain fluorescent probes. We investigated the connections of this tubular network using fluorescence, DIC and confocal microscopy. The large central vacuole is connected to an extensive reticulum of vacuolar tubules in the peripheral cytoplasm, continuous with the tubular vacuole network in the hyphal tip. This reticulate structure provides a large surface area for exchange across the tonoplast both in the growing region and in more mature parts of the hypha.

Keywords: Oomycete, Achlya, Saprolegnia, tubular motile vacuole, fluorescent tracer.

14. THE ROLE OF THE MOTILE TUBULAR VACUOLE SYSTEM IN MYCORRHIZAL FUNGI
Anne E. Ashford ¹ & William G. Allaway ²

1 School of Biological Science, UNSW, Sydney, N.S.W. 2052, Australia.
2 School of Biological Sciences A12, The University of Sydney, N.S.W. 2006, Australia.

Ectomycorrhizal fungi benefit the plant by transferring N, P and other elements from distant soil sites to the fine roots. Mycelium grows out from ectomycorrhizal roots into the soil, extending the effective soil exploitation. Work with an Australian ectomycorrhizal Pisolithus indicates that tubular motile vacuoles are involved in transport. The vacuole system is visualised by loading the vacuoles with fluorescent probes that accumulate in the vacuole lumen: DFFDA (Oregon Green 488 carboxylic acid diacetate, a fluorinated analogue of carboxyfluorescein diacetate) is our preference. Many members of Basidiomycotina, Ascomycotina, Deuteromycotina and Zygomycotina have tubular motile vacuoles, including Paxillus involutus (Batsch : Fr.) Fr. and Suillus granulatus (L. : Fr.) O. Kuntze, important ectomycorrhizal fungi (Rees et al., Mycol. Res. 98: 985-992, 1994). Tubular vacuoles are also seen in hyphal coils of ericoid mycorrhizas in Calluna vulgaris after treating the hair roots with DFFDA. Tubular vacuole systems can readily be demonstrated in synthesised Eucalyptus pilularis/Pisolithus mycorrhizas, but field-collected mycorrhizas have not proved so tractable. In beech and oak ectomycorrhizas we found little uptake of probe, although tubular vacuoles were detectable in cases where it was taken up. We interpret the lack of labelling as being primarily due to failure of the probe to gain access to the hyphal plasma membrane, owing to the impregnation of hyphal walls and sheath interstices with hydrophobic materials. This re-emphasises the likelihood that the mycorrhiza itself functions mainly as an exchange and storage structure. The main uptake-whether of nutrient ions or fluorescent probes-must take place in outlying hyphae.

Keywords: Tubular motile vacuole, mycorrhiza, phosphate, fluorochrome, mycelium.

15. LACCASE GENE AMPLIFICATION IN AUSTRALIAN STRAINS OF THE GENUS PYCNOPORUS
Kirsten Schliephake & Greg Lonergan

Centre for Applied Colloid and BioColloid Science, Swinburne University of Technology, P.O. Box 218, Hawthorn, Victoria 3122.

A study was undertaken to detect laccase in the genomic DNA of six Australian strains of the genus Pycnoporus by using primers designed to detect laccase 1 and laccase 2 gene in Pycnoporus cinnabarinus PB (ATCC 200478). Both laccase-encoding genes of P. cinnabarinus PB have been been cloned and their genomic sequence analysed. After three rounds of amplification only P. coccineus 1096 gave a gene amplification product of the expected size of 2132 base pairs when targeted with specific primers (Pc106s-SP1-3') designed for the laccase 1 gene from P. cinnabarinus PB. In the cases of the remaining fungi, the specificity of the laccase 1 primers resulted in no binding to the target site on the DNA template and hence no amplification of the DNA fragments. Amplification using semi-specific primers (Pc106s-FlCu4N) resulted in products of the expected size of 1986 base pairs for P. coccineus 1096 and P. cinnabarinus QLD. A different combination of semi-specific primers (Pc345s-FlCu4N) amplified products of the expected size of 1523 base pairs for all organisms tested. A further amplification of the laccase 1 gene using a degenerate primer pair (FlCu1Ns-FlCu4N) in the first and fourth copper binding region gave no products for any of the organisms tested. There is evidence of the first copper binding region being blocked by introns in genomic DNAs of many fungal species. The results may therefore suggest that the first copper binding region was also blocked by the presence of an intron, similar to that observed in other fungal laccases.

Amplification using specific primers for a laccase 2 gene identified in P. cinnabarinus PB, gave products of the expected size of 1069 base pairs for P. cinnabarinus VIC (CBS 101046), P. cinnabarinus QLD, P. coccineus 1096, P. coccineus 6004A and P. sanguineus 2256. This result showed a positive presence of a second laccase gene in the above named species. Another laccase producing fungus, Perenniporia tephropora, gave no amplification product using primers for the laccase 2 gene.

Laccases belong to a group of enzymes known as blue copper oxidases and participate in the oxidation of phenolic substructures of lignin. Pycnoporus cinnabarinus PB and P. cinnabarinus VIC have been extensively used in degradation studies of lignin-related compounds and dye molecules and their purified enzymes have previously been shown to have similar physical and chemical characteristics. Structural differences at the molecular level of the laccases point to noteworthy genetic variation between all the Australian isolates. Similarly, the expression of either laccase 1 or laccase 2 is contingent on medium conditions and the presence of inducers and may affect degradative abilities.

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