Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme IV: POPULATION DYNAMICS AND ECOLOGY Posters
RFLP of the ITS region of the fungal rDNA. The ECM
community changed along the investigated transect. A
Russula sp., Tylospora spp., a Tomentella sp., and
Cenococcum geophilum were the most commonly found
ECM taxa along the transect. Species not producing
conspicuous sporocarps constituted a high proportion of the
belowground ECM community. Tylospora asterophora,
Amphinema byssoides and all taxa identified as Cortinarius
spp. were associated with the nutrient-rich end of the
transect, whereas the Russula sp. and Piloderma spp. were
associated with the nutrient-poor section of the transect.
Nitrogen availability, pH and supply of base cations
appeared to be the most important soil factors controlling
the ECM community structure in the O horizon of the
Betsele site.
985 - The impact of ash fertilization on the biomass of
roots and ectomycorrhiza of coniferous trees
H. Jokinen 1* , R. Strömmer 1 , A. Holma 1 & H.M. Potila 2
1 University of Helsinki, Department of Ecological and
Environmental Sciences, Niemenkatu 73 FIN 15140 Lahti,
Finland. - 2 Forest Research Institute, Parkano Research
Station, FIN 39700 Parkano, Finland. - E-mail:
hanna.k.jokinen@helsinki.fi
Wood ash from the forest industry constitutes a
considerable waste problem, and recycling it back to the
forest is of great interest. Ash could be seen as a valuable
resource since it contains most of the elements needed for
plant nutrition and growth. The environmental issue
concerning ash is that it stimulates nitrogen mineralization,
increases soil pH and also contains heavy metals. Several
aspects concerning ash fertilization have been studied for
these reasons, especially the processes in forest soil, like
microbial activities, nutrient mineralization and responses
of various soil organisms. We studied the biomasses of the
roots and ectomycorrhiza in a dry, nutrient poor Scots pine
(Pinus sylvestris) forest in Muhos, northern Finland before
and after fertilization with wood ash. The results after the
first season were unexpected, as both these biomasses
slightly increased due to strong ash application, 9000 kg
ha -1 . For getting more thorough picture and long term view,
the sampling repeated three years later. Another field
experiment started in Evo, in Southern Finland in a more
nutrient rich Norway spruce (Picea abies) forest. We also
established a microcosm experiment for estimating the
capacity of mycorrhizal root tips and extramatrical
mycelium in storing N and thus alleviating the high spatial
and temporal variation in nitrogen mineralization in forest
soil after ash fertilization.
986 - Effect of grassland plant species on soil fungal
communities: a microcosm study
N. Kennedy * , E. Brodie & N. Clipson
Dept. Ind. Microbiology, UCD, Belfield, Dublin 4, Ireland.
- E-mail: nabla.kennedy@ucd.ie
Grasslands are the main vegetational class in Ireland and
are of major significance in agriculture. Although
intensification has been central to increased productivity in
Ireland, there is concern globally and within the EU about
the sustainability of such practices and a need to
understand at a basic level how grasslands function. It is
known that fungi play a major role in grassland ecosystem
processes such as carbon, nitrogen and other nutrient
cycles. In this study, microcosms were planted with seven
grassland species representing the most commonly found
plants in both unimproved, species-rich grasslands, and in
improved, fertilised grasslands, which are typically
dominated by only a few plant species. After harvest, shifts
in the fungal community structure of the rhizosphere soil of
each plant species were assessed. The ergosterol content of
each soil sample was measured in order to get an indication
of fungal biomass. In addition, samples were analysed
using TRFLP (terminal restriction fragment length
polymorphism). The resulting profiles, which indicated the
number of fungal species per sample, were compared
between plant species. In general, fungal communities were
not significantly altered by plant species. The similarity of
fungal profiles was even more striking when compared to
bacterial profiles for the same soils, which differed
significantly according to plant species type.
987 - Dynamics of VA mycorrhizal fungi in burned
Japanese red pine forests in the Setouchi Destrict in
Western Japan
S. Kinugasa 1 , M. Fujiyoshi 1 , T. Satomura 1 & T.
Horikoshi 2*
1 Graduate School of Biosphere Sciences, Hiroshima
University, Higashi-hiroshima 739-8521, Japan. - 2 Faculty
of Integrated Arts and Sciences, Hiroshima University,
Higashi-hiroshima 739-8521, Japan. - E-mail:
takao@hiroshima-u.ac.jp
Many large forest fires have occurred in the Japanese red
pine forests of the Setouchi District in Western Japan. We
investigated the seasonal changes of infection rate,
numbers of spores and sporangiocarps, and composition of
spore types of VA mycorrhizal fungi at the burned and the
vegetation naturally recovered sites (BNR sites,7 and 22
yrs after the fires) and the burned and planted site (BP site,
7 yrs after). 1. Infection rate is about 90% irrespective of
the sampling months at the BNR-22 yrs site. Infection rates
at the BNR-7 and BP-7 yrs sites showed the similar trends,
70-90% in July-September, and then gradually decreased to
50-60% in January. 2. Number of spores at the BNR-22 yrs
site is always higher (400-900/10 g dry soil) than those at
Book of Abstracts 297