Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme IV: POPULATION DYNAMICS AND ECOLOGY Posters
related to salinity and inundation levels and positively with
species diversity and nitrogen content of the sediments.
None of the 46 species of micro-fungi isolated was
halophile, only adaptive halotolerance was observed in
most of them. While population of most halotolerant
species declined with increasing salinity, the same for some
remained constant and for a few increased. Although ED50
salinity concentration for in vitro growth retardation of the
isolates varied between 8.2 - 14.5 dSm-1, they differed in
growth dynamics from their mesic counterparts between
3.0-5.5 dSm-1, suggesting a lower salinity tolerance limit
for physiological function than for their ecosystem
presence. Comparison of the population fraction of
cellulose decomposer and insoluble phosphate solubilizer
fungi, their diversity and distribution, in vitro
decomposition-solubilization ability and limits of salinity
tolerance with that of sediment bacteria indicated that the
fungi were no less significant as a population group of
carbon and phosphorus cycling microorganisms in the
extreme saline environment.
946 - Comparison of the post-fire dynamics of the
ectomycorrhizal community in two Quercus ilex stands
in northern Spain
V. Clavería * , A.M. de Miguel & M. de Román
Dep. Botany. University of Navarra, C/Irunlarrea s/n
31080 Pamplona, Spain. - E-mail:
vclaver@alumni.unav.es
A comparative study of the post-fire recolonization of
ectomycorrhizae in a evergreen oak stand (Quercus ilex L.
subs. ballota (Desf.) Samp.) has been carried out in two
Quercus ilex stands located in Nazar and San Cristóbal
(Navarra, Spain) respectively. The research in our group
has been focused during the last three years on the
description and identification of ectomycorrhizae in burnt
Quercus ilex stands, and in adjacent areas which were not
affected by fire and act as control plots for the study. In
1993 a stand in Nazar burnt, but it was not until 1998 that
the study started. On the contrary, the study in San
Cristóbal started immediately after the stand had burnt (in
the year 2000), thus enabling us to analyse the mycorrhizal
communities in the first stages after the fire. Therefore we
have been able to compare the regeneration in both stands
and the species composition five years after the fire and
immediately after the fire. The sampling of
ectomycorrhizae has been done in Nazar seasonally for
three years while in San Cristóbal the monitoring of the
mycorrhization has been done according to the same
methodology during one and a half years so far. The
description of several of the most important morphotypes
of ectomycorrhizae found in both stands are provided,
including photographs of different macroscopic and
microscopic features of the mycorrhiza.
947 - Influence of mycorrhizal inoculum on clonal
propagation in Epacris impressa Labill.
M. Conomikes 1 , C.B. McLean 1* , M.C. Starrett 2 & A.C.
Lawrie 3
1 University of Melbourne, Institute of Land and Food
Resources, School of Resource Management, Burnley
College 500 Yarra Boulevard, Ricmond, Victoria, 3121,
Australia. - 2 University of Vermont, College of Horticulture
and Life Sciences University of Vermont, Burlington,
Vermont, U.S.A. - 3 RMIT University, Department of
Biotechnology & Environmental Biology, GPO Box 71,
Bundoora, Vic, 3083, Australia. - E-mail:
cmclean@unimelb.edu.au
Members of the Epacridaceae are traditionally difficult to
propagate and are in decline in parts of Australia. Attack by
soil-borne fungi has led to some species of Epacridaceae in
Western Australia being listed as endangered. Seed is
nearly impossible to germinate and cuttings often have a
strike rate as low as 10%. Previous studies have shown that
introduction of soil collected from beneath adult plants
showed improved health and survival of cuttings of several
epacrid species. In this study cuttings were grown in either
potting mix alone or potting mix containing either
mycorrhizal inoculum or soil from beneath adult plants
collected in the wild. Plants were grown under glasshouse
conditions for 20 weeks and monitored for health and
survival before harvesting. Strike rate and mycorrhizal
status was then determined. Statistical analysis of results
showed no significant difference between treatments and
no mycorrhizas present in the roots of any cutting in any of
the treatments.
948 - The development and use of co-dominant SNPs
and SSRs in the study of gene flow in Scottish late
blight populations
D.E.L. Cooke * , A.K. Lees, S. Hussain, L. Sullivan, N.A.
Williams & J.M. Duncan
Host Parasite Co-evolution, Scottish Crop Research
Institute, Invergowrie, Dundee, DD2 5DA, U.K. - E-mail:
dcooke@scri.sari.ac.uk
Potato blight is the most serious diseases of the potato
industry worldwide. Infecting both the foliage and tubers, it
reduces yield and quality of ware and seed potato crops. A
survey of Scottish potato blight (Phytophthora infestans)
populations from 1995-1997 yielded 500 isolates from over
80 disease outbreaks. The isolates were characterised by
mating type, fungicide sensitivity and AFLP fingerprinting.
These data were examined alongside cropping details to
determine the population structure in the context of
existing disease management. Both mating types were
found and considerable AFLP diversity observed. Three
sub-populations were identified with higher ratio of the A2
mating type within one group. Evidence of occasional
sexual recombination, and thus gene flow was observed.
Book of Abstracts 285