Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme I: BIODIVERSITY AND CONSERVATION Posters
frustulosus (22/22), etc. The following species were
frequent on Fagus spp.: Fomes fomentarius L type (7/7),
Fomes fomentarius S type (19/21; 1 on Styrax obassia, 1
on an undetermined tree), Protodaedalea hispida (13/14; 1
on Quercus sp.), etc. Fomitopsis cf. cajanderi was always
on Prunus spp. (4/4). Melanoporia castanea was usually
on huge trees with more than 50 cm diam or on branches of
huge trees. It is suggested that loss of old growth forests
may reduce diversity of wood-decaying basidiomycetes
such as those restricted to Fagus spp. and huge Quercus
spp.
518 - The discovery of Cryphonectria cubensis on native
Syzigium spp. from South Africa
R.N. Heath * , M.V. Gryzenhout, J. Roux & M.J. Wingfield
University of Pretoria, Department of Microbiology and
Plant Pathology, Forestry and Agricultural Biotechnology
Institute, 74 Lunnon road, Hillcrest, Pretoria, 0002, South
Africa. - E-mail: Ronald.Heath@FABI.up.ac.za
Cryphonectria cubensis is a pathogen on Eucalyptus
species and Syzigium aromaticum in tropical and
subtropical regions worldwide. The pathogen has also been
reported from Tibouchina species (Melastomataceae) in
Colombia and South Africa. A previous hypothesis has
been that C. cubensis was introduced into South Africa
from South America. However, sequence data derived from
β-tubulin, histone H3 genes and disease symptoms have
been used to show that South African isolates of C.
cubensis are different to those from South America, Central
Africa and South East Asia. During disease surveys in
indigenous forests of South Africa, fruiting structures
resembling the anamorph of C. cubensis were found on
native S. cordatum and S. guanennsi. Teleomorph
structures were found on samples from the Northern and
KwaZulu Natal provinces. The fungus from these native
Syzigium spp. was broadly identified as C. cubensis based
on morphology. Comparisons of β-tubulin sequence data
showed that collections from the native Syzigium spp.
group together with South African isolates from
Eucalyptus. Results of this study indicate that the
Eucalyptus pathogen in South Africa, currently known as
C. cubensis, occurs on native Syzigium spp. in this country.
Furthermore, they add convincing evidence to the view that
C. cubensis in South Africa, is a species different to that
occurring elsewhere in the world and that it is native to
South Africa, where it has infected exotic Eucalyptus.
519 - What does rare wood-associated fungi really
want?
J. Heilmann-Clausen 1* & M. Christensen 2
1 Forest and Landscape Research Institute, Denmark. -
2 Royal Veterinary and Agricultural University, Denmark. -
E-mail: jhc@kvl.dk
158
Book of Abstracts
Based on studies in Danish deciduous forests, we examine
the importance of environmental conditions and wood
quality for macro-fungal diversity (as sporocarps) in
decaying wood, in order to provide practical conservation
guidelines for this group. Although we found species
richness to increase with wood volume, threatened species
did not appear in general to prefer large logs. Rather, we
found small logs to host more threatened species per
volume unit than larger logs. Similarly, branches (diam.
>10 cm) appeared to be richer in species than logs. Logs in
intermediate stages of decay were found to be most species
rich, especially with respect to threatened species. By
analysing modified data sets we found that even a short gap
in the supply of dead wood might significantly decrease the
number of threatened fungi at forest level. Tree species
diversity was found to be partly reflected in the diversity of
wood associated fungi. However, some tree species appear
to have rather similar fungal species assemblages and does
not independently add to overall species richness at local
scale. Local variation in microclimate was found to have
limited importance for fungal diversity. Among localities,
however, we found huge variation in the frequency of
threatened species, which seem to be partly reflected by
variation in microclimatic stress levels, partly by
differences in forest history. Selecting the right sites for
forests reserves is crucial for an efficient protection
strategy.
520 - Molecular analyses of arbuscular mycorrhizal
fungal species communities
I. Hijri 1 , F. Oehl 1 , K. Ineichen 1 , P. Mäder 2 , A. Wiemken 1 &
D. Redecker 1*
1 Institute of Botany, University of Basel, Hebelstr.1, 4056
Basel, Switzerland. - 2 Institute of Organic Agriculture
(FIBL), Ackerstr., 5070 Frick, Switzerland. - E-mail:
dirk.redecker@unibas.ch
Species communities of arbuscular mycorrhizal fungi
(AMF) were studied using a set of primers specifically
targeted at the ribosomal RNA genes. Small subunit and
Internal Transcribed Spacer sequences were amplified from
colonized roots and analyzed phylogenetically. Soil and
roots were sampled from field sites under organic or
conventional agricultural management widely differing in
input intensity as well as from semi-natural grassland. Trap
cultures set up from the respective field soils were also
characterized. All sites are situated in the three-countrycorner
France/Switzerland/Germany, most of them on
Loess soils. A wide range of fungi was detected in the trap
cultures, comprising Glomus, Acaulospora and
Archaeospora. The occurrence of generalist AMF and
specialists for specific field sites or types of agricultural
management was analyzed, as well as the spatial structure
of AMF communities.