Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme IV: POPULATION DYNAMICS AND ECOLOGY Posters
952 - Ecological specificity of Laboulbenia
(Laboulbeniales, Ascomycetes) through transmission
experiments and artificial infections
A. De Kesel
National Botanic Garden of Belgium, Domein van
Bouchout, B-1860 Meise, Belgium. - E-mail:
dekesel@br.fgov.be
Host specificity of Laboulbenia slackensis, and congeneric
taxa, was studied on living hosts and under controlled
conditions. From abiotic factors, soil composition and
relative humidity have the strongest impact on the fungus
population growth. The best growth conditions are close to
natural conditions. Transmission of L. slackensis is affected
by copulation, host population density and spore longevity.
Direct transmission is promoted by host copulation and
increasing host population density. It surpasses indirect
infection as spores are short-lived and soilborne infections
rare. Both transmission types enhance isolation and
promote specialization as they reinforce intraspecific and
obstruct interspecific transmission. Successful artificial
infections with L. slackensis, L. flagellata, L. giardii, L.
vulgaris and L. pedicellata were obtained on new carabid
hosts, providing that optimal growth conditions are met.
Hosts from non-carabid families could not be infected,
suggesting that physiological barriers are present, but
active on higher taxonomic levels. The specialization of
Laboulbenia species, with a narrow natural carabid host
range, is explained by (1) a physiological dependence and
obligate ectoparasitism to Carabidae, (2) a certain degree of
isolation due to the lack of interspecific transmission (time
and space) between potentially suitable carabid hosts and
3) the adaptation of the ectoparasite to a specific
environment which is rigorously chosen by the host.
953 - Fungal biodiversity in truffle beds in Navarra
(Spain): Ectomycorrhizae and hypogeous fungi
A.M. de Miguel * , M. de Román, M.L. Etayo & V. Clavería
Dep. Botany. University of Navarra, C/Irunlarrea s/n
31080 Pamplona, Spain. - E-mail: amiguel@unav.es
Since 1993 we have been studying the ectomycorrhizae of
truffle beds in order to know more about the evolution of
mycorrhizal colonization in plantlets artificially inoculated
with Tuber melanosporum. The richness of the
ectomycorrhizal community increased considerably during
the first sampling years, and we realised soon how
important the process of natural colonization was. Apart
from monitoring the permanence of the inoculated
mycorrhizae of Tuber melanosporum in field conditions,
we have recorded other Tuber mycorrhizae, as well as
mycorrhizal morphotypes belonging to the genera Genea,
Scleroderma, Hebeloma, Pisolithus and many Tomentellalike
morphotypes. Although the identity of most of the
mycorrhizal morphotypes is still unknown, the detailed
morphological and anatomical descriptions carried out will
probably enable us to identify the fungus forming the
mycorrhiza in future studies. On the other hand, we have
also studied the sporocarps, paying special attention to
hypogeous fungi and gasteromycetes due to their special
importance as ectomycorrhizal species. The
ectomycorrhizal morphotypes characterized and the
sporocarps collected in truffle beds will be presented,
together with some comments about the possible link
between them.
954 - Above- and below-ground views of tomentelloid
fungi in a Quercus ilex stand in northern spain
M. de Román * , A.M. de Miguel & V. Clavería
Dep. Botany. University of Navarra, C/Irunlarrea s/n
31080 Pamplona, Spain. - E-mail: mderoman@unav.es
Since autumn 1998 we have carried out seasonal samplings
of ectomycorrhizae in a Quercus ilex stand located in
Navarra (N Spain). The ectomycorrhizal morphotypes
found have been described and identified when possible,
yielding a total of 43 morphotypes. After three years of
study, one of the most outstanding facts is the great amount
of Tomentella-like ectomycorrhizae found, which account
for ca. 30% of the total mycorrhized root tips analysed.
Apparently, the situation changes considerably when we
consider the above-ground community. Few studies have
paid attention to resupinate fungi when collecting
ectomycorrhizal carpophores, thus inducing a mismatch
between the species composition above- and below-ground.
Nevertheless, a closer look at the ectomycorrhizal
carpophores, considering especially the resupinate
basidiomata, shows there is not such a big mismatch in our
study site. Tomentelloid fungi seem to be well-adapted to
survive in dry environments, such as the Mediterranean
region in which our study site is located, thus occurring
abundantly both as ectomycorrhizae and as carpophores. A
preliminary catalogue is presented, including the list of
tomentelloid fungi found both in the above- and belowground
communities as well as descriptions and pictures of
the ectomycorrhizal morphotypes and the basidiomata.
955 - Biosorption of copper by Auricularia polytricha
F. Di Mario * , E. Galli & P. Rapanà
IBAF-CNR, Via Salaria Km.29,300 00016 Monterotondo
Scalo (RM), Italy. - E-mail: francesca.dimario@mlib.cnr.it
The biosorption of copper ions has been studied using
lyophilised mycelium ofAuricularia polytricha (SMR 0055
of International Bank of Edible Saprophytic Mushrooms of
National Council of Research) in a batch system. This
isolate was chosen for its ability of producing large
amounts of biomass able to adsorbe metal ions.
Experiments were performed in a pH range 2 - 6 at
temperature within 15 - 35 °C, using different amounts of
mycelium (100, 200, 300, 400 mg) in the presence of 1, 5,
Book of Abstracts 287