© Benaki Phytopathological Institute
Hellenic Plant Protection Journal - Special Issue
70
time for sclerotia within the soil paste was
found to be fifteen days. If, by stereoscop-
ic examination nematodes or mites were de-
tected on the sclerotia, the affected plates
were then placed in an oven at 80° for four
hours. Under these conditions both nema-
todes and mites were killed while the sclero-
tia and any mycoparasites present were not
adversely affected. Subsequently, the plates
were incubated for a further 24-48 hours at
100% humidity until the appearance of ei-
ther phytopathogenic microbes or myco-
parasites was detected.
The presence of mycoparasites of sclerotia of the phytopathogenic
ascomycete
Sclerotinia sclerotiorum
in cultivated lands and a possible
relationship with organic matter
F.A. T
SAPIKOUNIS
*
Department of Biology, University of Patras, GR-265 00 Rio, Patra, Greece. *Present
address: Agiou Nikolaou 48, GR-270 52 Varda, Ilia, Greece
More than 80 soil samples from all over
Greece, from tree crops, open field vege-
tables, greenhouse vegetable crops, vine
crops and raisins, and gardens, were collect-
ed in order to identify sclerotia and to iso-
late mycoparasites. Cultivation was either
by conventional or organic methods. For the
detection of sclerotia two metal sieves with
holes of 4 and 7 mm, respectively were used.
For the isolation of sclerotial mycoparasites
using as traps sclerotia and pH, the texture
and organic matter were determined in soil
samples. Sclerotia were detected in 22.4% of
the samples, mainly on vegetables crops, re-
gardless of whether cultivation system was
organic or conventional. Hundreds of candi-
date mycoparasites were isolated and pre-
liminary evaluation showed that the major-
ity had mycoparasitic qualities or abilities.
From each soil sample 5 candidate myco-
parasites were isolated on average. Most
of them belonged to the genera of
Gliocla-
dium
,
Fusarium
,
Trichoderma
,
Coniothyrium
and the class of
Phycomycetes
. Mycopara-
site presence was directly proportional to
the concentration of organic matter. Also, in
organically-cultivated vegetable crops, the
presence of parasitized sclerotia was great-
er. It seems that the parasitism of sclerotia
and the overall presence of mycoparasites
is higher in soils where the concentration of
organic matter is increased. Mycoparasites
were also isolated from soil samples where
only traces of organic matter were present.
The treatment of organic matter should be
a top priority for all crops and basic fertiliza-
tion should be rational and based on analy-
sis of the soil.
Evaluation of surfactants in activation of the innate immune system of
the plant
Arabidopsis thaliana
F. A
GGELOPOULOU
, P.P. A
NTONIOU
, E.C. T
JAMOS
, J. K
UC
* and D.I. T
SITSIGIANNIS
Laboratory of Plant Pathology, Department of Crop Science, Agricultural University
of Athens, 75 Iera Odos Str., GR-118 55 Athens, Greece. *ex. Emeritus Professor, 5502
Lorna St., Torrance, CA 90503, USA
Verticillium wilt caused by the soilborne
pathogen
Verticillium dahlia
and bacteri-
al speck caused by
Pseudomonas syringae
pv.
tomato
are two very serious diseases of
crop plants. Management of these diseases
is mainly based on prevention, thus the dis-
covery of alternative means for their control
is essential. Induction of systemic acquired
resistance (SAR) could be an alternative
strategy of these diseases since there are
data of successful control of various plant
diseases with this method. The aim of this
