Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme IV: POPULATION DYNAMICS AND ECOLOGY Posters
968 - Adaptive spatiotemporal distribution of soil
microfungi in 'Evolution Canyon' II, Lower Nahal
Keziv, Western Upper Galilee, Israel
I. Grishkan * , E. Nevo, S.P. Wasser & A. Beharav
Institute of Evolution, University of Haifa, Mount Carmel,
Haifa 31905, Israel. - E-mail:
grishkan@research.haifa.ac.il
We describe and interpret spatiotemporal micromycete
community structure and adaptive complexes to xeric and
mesic contrasting microclimates in the soils of 'Evolution
Canyon' II, western Upper Galilee, Israel. A total of 192
species belonging to Zygomycota (9 species), Ascomycota
(13 species), and mitosporic fungi (170 species) were
isolated. The fungal communities on the xeric south-facing
slope (SFS) demonstrated significantly greater diversity
(species richness, Shannon index, and evenness) than on
the mesic north-facing slope (NFS). Seasonally, winter
slope communities were less heterogeneous. Forest
localities on the NFS and in all seasons and the shady
locality on the SFS in the winter were overwhelmingly
dominated by mesophilic Penicillium species. The sunny
locality on the SFS was characterized by a dominance of
melanin-containing fungi that was most pronounced in the
summer and by high occurrence and abundance of
thermotolerant Aspergillus and Fusarium species.
Ascomycetes and zygomycetes were the minor components
in all local mycobiota studied; sexual ascomycetes, being
stress-selected fungi, were more abundant than 10 fold in
the soil of the SFS, with the peak of abundance in the
sunny summer community. The results demonstrated a
microscale adaptive spatiotemporal inter- and intraslope
divergence in soil mycobiota structure. Microclimatic
natural selection appears to be the major factor affecting
soil fungi diversity patterns and spatiotemporal dynamics.
969 - Structural diversity of fungal populations in soil
under the influence of different farming management
systems
A. Hagn * , K. Pritsch & M. Schloter
GSF-Research Centre for Environment and Health, Insitute
of Soil Ecology, Ingolstädter Landstraße 1, 85758
Munich/Neuherberg, Germany. - E-mail:
alexandra.hagn@gsf.de
Although it is known that fungi play a vital role for
ecosystems, only few studies were published so far
showing fungal diversity and dynamics in soil. Mainly in
agricultural ecosystems fungi are essential for the soil
quality, as many species are able to degrade complex
organic compounds, supply plants with nutrients and serve
as biocontrol organisms against plant pathogens. However
some strains can also act as plant pathogens. Therefore we
investigated the influence of precision farming (a new
agricultural technique, focusing on the heterogeneity of a
field site and adapting the amount of fertilizer given to the
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Book of Abstracts
yield expected in a particular plot). For comparison
samples were also taken from plots, where fertilizers were
applied using conventional techniques. To access the
different fungal populations culture-dependent and cultureindependent
methods were used. Fungal cultures were
isolated on three different media and examined by means
of microscopy and a genetic fingerprinting method
(interLINE, PAGE). Additionally DNA was directly
extracted from the soil samples and clone libraries of the
18S rDNA were established. Yet the data of the culturedependent
and the culture-independent methos show a
seasonal influence as well as an influence of the high- and
low-yield areas. Besides also a direct influence of the
agricultural management systems on the structure of the
fungal populations was detected.
970 - Microbial companions of an introduced tree:
needle endophytes of Siberian larch (Larix sibirica) in
Finland
J. Hantula 1* , M. Kauhanen 1 , E.J. Vainio 1 & P. Niemelä 2
1 Finnish Forest Research Institute, PO Box 18, 01301
Vantaa, Finland. - 2 University of Joensuu, Faculty of
Forestry, PO Box 111, 80101 Joensuu, Finland. - E-mail:
jarkko.hantula@metla.fi
Endophytes are organisms inhabiting plant tissues without
causing symptoms. The distinction between pathogens and
endophytes is not clear as some endophytes are pathogenic
for other plants. Some pathogens also show periods of
latency. In single hosts pathogenicity or endophytic
behavior may be determined by only one gene. Plants are
frequently introduced to novel geographic areas in the
modern world. It is not known how commonly endophytes
are co-introduced with their plant hosts. This information
should, however, be available as nonindigeneous plants
may transport fungal endophytes pathogenic to native
plants. We analysed needle endophytes of Siberian larch in
its natural distribution area in Russia and in old or young
stands in Finland, where the tree does not occur naturally.
880 isolates were collected, and identified to species level
based on colony morphology and DNA-analyses. The cointroduction
frequency of endophytes turned out to be high;
only one common (in Russia) endophyte was missing from
one Finnish stand. In contrast, several rather common
endophytes observed in Finland lacked from the natural
stand in Russia. We also analysed genetic variation in one
endophyte species.
971 - Interspecific fungal interactions and recognition
in decayed wood
J. Heilmann-Clausen 1* & L. Boddy 2
1 Danish Forest and Landscape Research Institute,
Hørsholm Kongevej 11, 2970 Hørsholm, Denmark. -
2 Cardiff University, School of Biosciences, Museum
Avenue, PO Box 915, Cardiff CF10 3TL, Wales, U.K. - Email:
jhc@kvl.dk