Grassland fungi project

Systematics, barcoding and ecology of fungi from waxcap grasslands

A research project funded by DEFRA and Scottish Natural Heritage

Waxcap grasslands are fragile ecosystems known to contain a high diversity of fungi.

Fungi are uniquely challenging organisms for recognition, monitoring and conservation management. Apart from the sheer number of species, many are small and ephemeral [short lived], and need specialist knowledge and equipment for their identification. Some of their most obvious features (colour, size, shape etc.) vary immensely, causing further concerns for the field mycologist. Nevertheless, fungi play absolutely critical roles in ecosystem function, especially in carbon and nutrient cycling, root function in plants, and as a food source for a very wide range of organisms. Their study should therefore be a high priority, and modern methods should be explored to improve recording and monitoring techniques.

Accordingly, DEFRA and Scottish Natural Heritage (SNH) have come together to fund research into the classification and ecology of fungi from unimproved grassland habitats (so-called “waxcap grasslands”), which are fragile ecosystems known to contain a high diversity of fungi. They are especially vulnerable as “improvements” in the form of agricultural fertilizers cause the loss of many fungal species, with populations failing to recover for decades even after cessation of fertilization. The research is being carried out by a partnership between CABI, the Royal Botanic Gardens, Kew and the University of Aberystwyth with support from a large number of local fungal recording groups and expert individuals.

The fungal species of unimproved grasslands have not been studied in any detail using molecular methods. A key requirement for these and many other fungi of conservation concern in the UK is the need for molecular diagnostic tools, to assist species definition, identification and recognition of cryptic taxa. Bearing in mind the critical nature of morphological species definition for many of these fungi, the existence of cryptic species [hidden species that can't be differentiated visually] might be expected, and phylogenetic studies [relationship between species based on differences in their DNA] may also lead to detection of morphological traits that will improve the robustness of traditional identification methods. Identification of diagnostic (barcoding) DNA sequences will also allow detection of non-fruiting populations, a particularly important task bearing in mind the ephemeral and irregular fruiting events of many fungi.

Hygrocybe species from unimproved grasslands, collected as part of the project

Collections of the common species Hygrocybe conica, demonstrating the great range of variation within the species as currently accepted.

We intend to focus on two genera from the grassland system, the waxcaps themselves (Hygrocybe spp.) and the earthtongues (Geoglossum and relatives). Both groups have been the subject of long-term monitoring exercises, they have excited the attention of non-specialists, their presence has led to some of the few SSSIs in the UK designated for their non-lichenized fungi, and are included in sites analyzed in the Important Fungus Areas survey. Three species are included in the UK Biodiversity Action Plan (Hygrocybe spadicea, Geoglossum atropurpureum and Microglossum olivaceum), with a further 11 taxa placed on the provisional UK Red Data List for fungi – two of which have been proposed for inclusion in Schedule 1 of the Bern Convention. All four national statutory conservation bodies have funded survey and monitoring of these fungi. Despite all of this interest, neither group has been the subject of a modern systematic revision using molecular methods. Few authentic sequences are available, and the work to identify diagnostic barcode sequences has not been carried out.

Links with the field mycology community are critical to the project's success.

The project is based firmly in the laboratory, but effective links with the field mycology community are critical to its success. This is not just because the laboratory scientists need fresh material for analysis; field mycologists will be one the the primary beneficiary groups for the research and their needs and opinions will be fully taken into account. We have already received samples, images and collection data from 27 different vice-counties in England, Scotland and Wales. These freshly gathered samples will be combined with authentic material from Kew’s incomparable fungarium [the mycological equivalent of a herbarium], and from other key collections including those at the Royal Botanic Garden, Edinburgh and the University of Aberystwyth.

There will be two workshops in 2011 at which interim results will be discussed and guidance sought from stakeholders, in September (Mar Lodge Estate, Perthshire) and October (Plas Tan y Bwlch, Snowdonia; in collaboration with the British Mycological Society). These will allow work in the final year of the project to be more effectively targeted. The Mar Lodge workshop will be on the 24/25th September; for more information see the flyer or register your interest directly online.

The project will give us the capacity to develop novel monitoring methods, as recommended in the UK Strategy for conservation of fungi "Saving the Forgotten Kingdom". Next-generation sequencing approaches allow us to analyze fungal populations extracted directly from soil cores. This makes it possible not only to identify which species are present but also to study their relative abundance. This allows the analysis of non-fruiting fungal communities and can potentially reduce substantially the need for multiple field surveys to detect all the species that may be present. The work may also lead to more robust methodologies for selection of grassland SSSIs. Whilst issues of sampling intensity and the heterogeneous distribution of grassland fungi make it likely that traditional field surveys will still be useful, the ability to generate a species inventory by genetic means holds huge potential for fungal conservation.

This project will allow us to (a) define species using more objective criteria, using a combination of morphological and molecular methods; (b) recognize cryptic species that may need to be considered for conservation management; (c) gain a better understanding of the ecology of waxcap fungi, (d) designate barcode sequences to allow development of novel monitoring tools for non-fruiting populations, and (e) further improve the partnership between the scientific and lay communities to study these beautiful species.

For more information, contact:

Dr Paul Cannon

CABI and Royal Botanic Gardens, Kew

Richmond

Surrey TW9 3AB

email p.cannon<at>cabi.org