The 23rd nz fungal foray, waikanae, May 2009 Petra White Introduction

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Peter Johnston, Landcare Research, started the day with a talk on accumulating and managing the DNA sequence data for New Zealand fungi. In-house projects at Landcare Research are generating a lot of sequence data and users want access to that data. Information is delivered through the NZ Fungi database but it would be a much more powerful resource if we could add DNA information to the database. Such data for instance could benefit the Department of Conservation (DoC) data deficient fungi.

Professor Brandon Matheny, University of Tennessee, then spoke of the evolution of Australasian Inocybaceae. In the Paleogene, 65-24 million years ago, there was a dramatic climate change, a cooling down and eventual isolation of Australasia. Egon Horak described 17 species of Inocybe, but this genus deserves more work, as there are a lot more species than we think.

Kentaro Hosaka, from Japan’s National Museum of Nature and Science, described some preliminary results from multigene analysis of truffle-like fungi (Hysterangiales) and earthstars (Geastrales), two of the four major groups within Phallomycetidae, to understand the comparative biogeography of closely related but ecologically distinct groups. Earthstars grow above ground, are saprotrophic and spores are wind-dispersed, whereas the truffle-like fungi grow below ground, are ectomycorrhizal and small animals disperse the spores. The other two groups in Phallomycetidae are stinkhorns (Phellales) and coral and club fungi (Gomphales). Comparative biogeography of these four closely related groups will provide exciting incite into the fungal biogeography, still in a developing stage compared to plant and animal studies.
Next was Judy Gardner from Scion, who described her work on stream baiting for Phytophthora spp. as a surveillance toll in New Zealand. The genus Phytophthora is an Oomycete, which was previously included in the fungal kingdom but is now in kingdom Chromista. Phytophthora spp., commonly known as water moulds, produce motile zoospores and require water for dispersal. They are responsible for some of the most destructive plant diseases known to man. Examples include European potato famine of the 19th century (caused by P. infestans and P. cinnamomi), sudden oak death (P. ramorum) in western USA, and kauri dieback in New Zealand (P. taxon Agathis). To enable the evaluation for conditions in New Zealand and investigate the presence of Phytophthora spp. a series of traps were set up in six streams on the Volcanic Plateau. During a 12-month period over 300 cultures were collected for further evaluation.
Katrin Walbert, also from Scion, described her work on ectomycorrhizal fungi (ECM) in plantation forests of New Zealand. ECMs increase root spread by more than 40 times so that there is more uptake of nutrients by plants. The presence of these fungi can reduce the need for fertiliser. An examination of a nursery and four Pinus radiata stands of varying age in Kaingaroa Forest revealed 18 ECM species growing above ground and 19 ECM species growing below ground. The overall species richness and diversity was found to be low compared to similar forests in the Northern Hemisphere but similar to other exotic plantations in the Southern Hemisphere. ECM species identified in the nursery survived the first year of outplanting but were found to be completely replaced by forest ECMs after seven years, with the first non-nursery species appearing after six months. An earthball, Rhizopogon rubescens, was the most persistent and abundant ECM species.
Benjamin Myles, University of Otago, then spoke about his molecular phylogenetic work on the genus Menegazzia, which he described as New Zealand’s “holiest” (most perforated) lichen. Menegazzia is a genus of around 70 lichenised ascomycete species found throughout Australasia and South America. They are characterised by the easily noticeable perforations found throughout their upper thallus (apart from M. eperforata, which has none). They belong in the family Parmeliaceae, containing over 2000 species. There are 20 species in New Zealand, 12 being endemic. With Benjamin present our display tables were a little more diverse than usual with lichens appearing among the fungi.
Next Michael Lucas, University of Otago, presented work he and David Orlovich were doing on the genetic diversity of Cortinarius rotundisporus in Australia and New Zealand. Cortinarius is the most diverse ECM genus and very common in these two countries. C. rotundisporus has a blue-green pileus with a variable yellow central region and brown spores. It associates with Eucalyptus, Casuarina, Leptospermum and Kunzea spp. A study of genetic variation in C. rotundisporus (Sawyer et. al. 1999) found three phylogenetically distinct internal transcribed spacer (ITS) types (RFLP Types I, II and III), but the relationships of these ITS types to other described species was not investigated. Their preliminary results revealed 2 mostly Australian clades and 2 exclusively New Zealand ones in Type I, whereas Type II was related to C. tessiae and Type III was not related to the other two but rather to Cortinarius subgen. Dermacybe.
The next talk, entitled “The Time to Foray”, was by David Ratkowsky, University of Tasmania. He told us that the Aborigines had a different idea of seasonology. They knew a lot about the edibility of fungi but did not necessarily used fungi as an indicator of seasons. In Tasmania they had three seasons – wegtellanyta (December-April), tunna (May-August) and pawenya peena (September-November). Lists of macrofungi species from three separate studies in the Warra long-term ecological research site in southern Tasmania, where fortnightly visits were made over a 12-month period, show that the majority of species recorded were during the tunna season. David’s conclusion was that tunna is the best season to foray for fungi, particularly May-June.
After lunch Rytas Vigalys, Duke University, talked about the work he did probing fungal diversity using DNA sequence libraries, which revealed a diverse community of eukaryotic microorganisms in soils from southeastern USA Peidmont forests. These communities are dominated by fungi, but also include protistan, chorophyte and metazoan lineages. Using phylogenetic analysis and ITS sequences from basidiome surveys and environmental sources, identification to species level was possible for many common Agaricomycetes such as Russula, Suillus, Mycena and Gymnopus. This sequence data is being used to study how fungal communities respond to environmental perturbation. Examples include study of community shifts in response to CO2 enrichment and community response to long-term land use histories with different recover histories.
Then Teresa Lebel from the Royal Botanic Gardens, Melbourne spoke on the demise of the sequestrate genus Endoptychum, truffle-like forms of Agaricales where the spore mass is enclosed. This genus is now known to be an assemblage of species that are not closely related. The type E. agaricoides was found to be more closely related to the genus Chlorophyllum and is now listed as C. agaricoides. Endoptychum depressum was found to be more closely related to Agaricus and is now known as A. inapertus. Finally Chlorophyllum was conserved against the name Endoptychum, which left several European and all Australian species of Endoptychum in nomenclature limbo. Examination of hundreds of collections revealed the presence of eight Australian species, which analysis of DNA sequences suggests has affinities with several lineages of Agaricaceae, including Macrolepiota, Agaricus and Chlorophyllum.
Dee Carter, University of Sydney, gave a talk on the basidiomycete yeast genus Cryptococcus, a true fungal pathogen acquired from the environment and established first in the lungs. The fungus is not returned to the environment unless the host dies. It is capable of causing life-threatening diseases in mammals, including humans. Cryptococcus neoformas, found in high numbers in pigeon guano, causes a severe form of meningitis and meningo-encephalitis in people with AIDS. Cryptococcus gattii affects otherwise healthy people, is more restricted in distribution and is associated with decaying wood.
The next talk, from Bevan Weir, Landcare Research, concerned the ascomycete genus Colletotrichum (teleomorph: Glomerella), a plant pathogen affecting cereals, grasses, legumes, vegetables and fruit. Typical disease symptoms are characterised by sunken necrotic lesions with orange conidia. Colletotrichum gloeosporioides causes quince (Cydonia oblonga) and apple (Malus domestica) bitter rot, anthracnose on many fruit and vegetable species such as mango (Mangifera indica) or cultivated plants like St. John’s wort (Hypericum perforatum), and rubber leaf spot on Hevea brasiliensis. Multiple gene sequences from a global collection of vouchered specimens were used to identify genetically distinct groups within C. gloeosporioides. He concluded that multiple gene sequences, appropriately analysed, can be used in conjunction with other characteristics to define biologically meaningful species and subspecies.
Pam Catcheside, Flinders University, then told us how she and her husband David had 10 years previously started to document the fungi of South Australia, including Kangaroo Island. A number of “fungal hotspots” (high species diversity, high numbers of fruiting bodies, fungi of conservation importance) have been identified from surveys in parks in seven regions of the State since 1997. One hotspot, Stringybark Walking Trail in Deep Creek Conservation Park, has remnant vegetation of Australian oak (Eucalyptus obliqua) and an understory of tufted grass tree (Xanthorrhoea semiplana subsp. semiplana). The number and diversity of fungal species in this small area exceeds that at all other locations surveyed, with the exception of the much larger and ecologically more diverse Flinders Chase National Park on Kangaroo Island. Australia lags behind other countries in assessing the conservation status of fungi. A recent study (Grgurinovic and Simpson 2001) assessed 443 fungi for rarity but this was based only on the collections of J. B. Cleland. The Catchesides want to get fungi on the threatened species lists for South Australia. One example is Mucronella pendula, which is only known from one rotting log.
Genevieve Gates, University of Tasmania, followed with a talk entitled “A Bunch of No-Good Rotters.” Sustainable forestry in Tasmania aims to retain all elements of a natural forest cycle in its management plan. In the wet Australian oak forests of southern Tasmania, wildfire at different intervals has produced a mosaic of multi-aged stands with a successional climax of temperate rainforest after 400 years in the absence of fire. There are several heart rot polypores (Fomes hemitephrus, Australoporus tasmanicus, Phellinus wahlbergii) found in these forests that appear to be either host-specific or confined to fruiting on large diameter eucalypts. Such trees are found in the older forests (>250 years) or as legacies of wildfire disturbance in the younger stands. The logging of old growth forests, the silviculture treatment of clearfell, burn and sow, and current rotation lengths of 80-100 years will see the loss of large diameter trees and the consequent risk of local disappearance of these polypores.
The last speaker for the day was Peter Johnston, Landcare Research. He was getting together a revised list of threatened fungi that he hoped to have compiled by the end of the year and then published. The initial list of 2002 only had macrofungi. Lichens were not included in the threatened species list. The previous year the DoC had asked for an update but nothing eventuated except one submission from Pat Leonard.

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