© Benaki Phytopathological Institute
Abstracts - 16th Hellenic Phytopathological Congress
73
and D. G
OUTOS
1
1
Laboratory of Plant Pathology,
2
Laboratory of solid waste and wastewater
management School of Agricultural Technology, Technological Educational
Institute of Crete, Stavromenos, GR-710 04 Iraklio, Crete, Greece.
3
Laboratory of Plant
Pathology, Plant Protection Institute of Iraklio, Hellenic Agricultural Organization
“Demetra”, Mesa Katsampas, GR-710 03 Iraklio, Crete, Greece
Evaluation of the suppressive effect of six composts (A, B, C, D, E and Z) against verticillium
wilt of eggplant was carried out. The sup-
pressive action of the compost, on the ba-
sis of its phenolic composition was further
investigated. Results showed that composts
C, D, E and Z reduced verticillium wilt symp-
toms, as well as the fungal biomass in the
xylem vessels, despite the high inoculum
density (45 microsclerotia g
-1
soil) which was
applied. Composts E and Z (originating from
plant residues and olive leaves, olive mill ex-
tracted press cake, and olive mill waste wa-
ter, respectively) showed the highest sup-
pressive effects, reducing significantly the
disease severity, disease incidence and rel-
ative area under disease progress curve (rel-
ative AUDPC). The observed decrease in
symptom severity was associated with sig-
nificant reduction of
V. dahliae
biomass in
the vascular tissues as well as with a low-
er total phenol content in plant stems, in-
dicating lower levels of pathogen infection.
The total phenol content of the pure com-
posts as well as of mixtures (consisting of
20% compost - 80% substrate) where the
plants grew with differing disease severity,
was also assessed. Results showed that the
total phenol content of composts with sig-
nificant suppressive effect against
V. dahliae
(C, D, E and Ζ) was significantly higher that
that of the non suppressive composts. In ad-
dition, the total phenol content of mixtures
(20% compost - 80% substrate) with a sig-
nificant suppressive effect was about 400%
higher than those of the pure substrate and
the non suppressive compost A, indicating
the importance of these compounds for dis-
ease suppression mechanisms.
Comparative study of phytopathogenic fungi growth in two greenhouse
tomato farming systems
M. P
APADOPOULOU
Technological Educational Institution (TEI - K) Antikalamos, GR-241 00, Kalamata,
Greece
Soil microorganisms significantly affect
plant growth, but in agricultural ecosystems
their growth, diversity and activity depend
to a large degree on the management of the
soil. The purpose of this study was to inves-
tigate the effect of different cultivation tech-
niques on the development of soil microor-
ganisms and phytopathogenic fungi. Soil
samples were collected (2009-2010), from
three greenhouses (Triphylia area, Kyparis-
sia) sown with different tomato varieties,
and exposed to different regimes of appli-
cation of fertilizer and pesticides. Soil mi-
crobial biomass was determined using the
Chloroform Fumigation Extraction Meth-
od (CFE), the respiratory activity of micro-
organisms (Rbasal) was examined, and the
total number of soil fungi (phytopathogen-
ic or not) was determined
in vitro
by the
method of successive dilution and colony-
forming units (CFU) assay. The nutrient me-
dia used for the isolation of fungi were PDA,
oatmeal agar, corn meal agar, strep RBA,
Botrytis
sporulation agar, Czapek (Dox) agar,
and
Fusarium
medium. A comparative eval-
uation of the samples showed that the var-
iation in soil species biodiversity depends
on the addition of organic matter and im-
