Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme III: PATHOGENS AND NUISANCES, FOOD AND MEDICINE Posters
817 - Dimmeric naphtoquinone metabolite aurofusarin
- new mycotoxin produced by Fusarium graminearum
J. Dvorska
Sumy State Agrarian University, Kirova Str 160/5 Fl 91,
Sumy 40021, Ukraine. - E-mail: ppdvorska@rs.net.ua
Fusarium species of fungi produce a range of mycotoxins
(trichothecene, zeralenone and fumonisins). There is a
group of pigments which are produced by Fusarium
species and they have been ignored until recently. A
comprehensive work conducted by Kotyk (1999) with such
a pigment, aurofusarin, clearly has shown that this
compound could be included into the list of important
Fusarium mycotoxins. A series of our experiments on
effect of aurofusarin on quails showed that there was no
toxicity signs when the compound was fed at a level of
26.4 mg/kg. Egg production was decreased, but body
weight egg weight and yolk/albumin proportions did not
change. There were negative changes in immune system of
quails (titre antibody to Newcastle disease significantly
decreased and the spleen was reduced in size). Antioxidant
system of the adult quails was compromised as a result of
aurofusarin consumption. Histochemical studies revealed
degenerative changes in kidney (degeneration and
resorption of the glomeruli). The ovary was brown in
colour with a decreased weight and number of follicles,
and liver was enlarged with haemorrhages. The egg yolk
colour was changed from yellow-orange to browngreenish.
Aurofusarin decreased DHA proportion in egg
yolk lipids and increased linoleic acid concentration.
Concentrations of vitamin E, carotenoids and vitamin A in
the egg yolk also decreased as a result of aurofusarin
supplementation. Fertility and hatchability of aurofusarin
enriched eggs was decreased.
818 - Traumatic oil glands induced by pruning in the
wound-associated phloem of Eucalyptus globulus:
chemistry and histology
A. Eyles 1* , N.W. Davies 2 & C. Mohammed 3
1 Co-operative Research Centre for Sustainable Production
Forestry., GPO Box 252-12 Hobart, Tasmania, 7001,
Australia. - 2 Central Science Laboratory, University of
Tasmania, GPO Box 252-74, Hobart, Tasmania, 7001,
Australia. - 3 CSIRO Forestry and Forest Products, GPO
Box 252-12, Hobart, Tasmania, 7001, Australia. - E-mail:
Alieta.Eyles@ffp.csiro.au
The natural occurrence of oil glands in various organs such
as bark and leaves is well established as a characteristic of
Myrtaceae, but this is the first reported case of traumatic oil
glands induced in response to wounding. The new phloem
enveloping the wound, which was formed in the two years
following pruning in 5-year-old Eucalyptus globulus, was
morphologically distinct from healthy stem phloem.
Histological examinations revealed this wound-associated
phloem to be largely composed of secretory cavities similar
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Book of Abstracts
in appearance to oil glands. Subsequent analysis of the
wound-associated phloem extracts by GC-MS confirmed
the presence of volatile terpenes and phenols. The total oil
content determined for wound-associated phloem extracts
was significantly higher (>50 times) than for healthy stem
phloem extracts. The identities of twenty-six components
of the oil extracts and their approximate relative
abundances are presented. Implications of the role of
terpenes as an inducible secondary metabolite in tree
wound responses are discussed.
819 - Host response to natural infection by a stem
canker (Cytonaema sp.) in the aerial bark of Eucalyptus
globulus: a preliminary report
A. Eyles 1* , N.W. Davies 2 , Z.Q. Yuan 1 & C. Mohammed 3
1 Co-operative Research Centre for Sustainable Production
Forestry., GPO Box 252-12 Hobart, Tasmania, 7001,
Australia. - 2 Central Science Laboratory, University of
Tasmania, GPO Box 252-74, Hobart, Tasmania, 7001,
Australia. - 3 CSIRO Forestry and Forest Products, GPO
Box 252-12, Hobart, Tasmania, 7001, Australia. - E-mail:
Alieta.Eyles@ffp.csiro.au
The chemical and anatomical host responses to natural
infection by a Cytonaema sp. in the aerial bark of 3-yearold
E. globulus plantation trees were examined for the first
time. The lesion margin (LM) of the canker-infected bark
was characterized by the formation of a layer of dark
extractives visible to the naked eye. Chemical analysis of
the LM by GC-MS, HPLC-UV and HPLC-MS using
negative ion electrospray ionisation indicated the presence
of a range of compounds including hydrolyzable tannins,
proanthocyanidins, flavonone glycoside, formlyated
phloroglucinol compounds and volatile terpenes. These
compounds were either undetectable in healthy tissue or
else present at significantly lower concentrations than in
the LM. The LM of the canker-infected bark was
morphologically distinct from healthy phloem, its
characteristics varying depending on severity of canker
infection. In superficial infections (in which only the
phloem was affected), three types of LMs were observed i).
a continuous ligno-suberized boundary zone of multiple
layers positioned between polyphenolic parenchyma cells
ii). a boundary zone comprising of only polyphenolic
parenchyma cells derived from the de-differentiation of
pre-existing parenchyma cells iii). a combination of i and
ii. In cases of severe canker infections in which the
vascular cambium had been killed, the new phloem formed
subsequently contained traumatic oil glands in addition to
the responses observed for superficial canker infections.
820 - Breeding bread wheat with multiple resistance
and high yield for Ethiopia
H. Fehrmann 1* , S. Assefa 2 & A. Badebo 2
1
Institute für Pflanzenpathologie und Pflanzenschutz,
University of Göttingen, Germany. -
2
Ethiopian