© Benaki Phytopathological Institute
Abstracts - 16th Hellenic Phytopathological Congress
87
Strobilurins have rapidly become an impor-
tant class of agricultural fungicides. Their
activity is due to their ability to inhibit mi-
tochondrial respiration, thus disrupting the
energy cycle within the fungus. In addition
to serving as potent fungicides, they have
been reported to offer protection to plants
by increasing their capacity to activate cel-
lular defence responses and promote plant
growth (greening effect). The strobilurin
class fungicide pyraclostrobin is registered
for use in several crops across Europe. In this
work, we present the efficacy evaluation
of pyraclostrobin against bacterial and vi-
ral diseases. Specifically, the incidence and
development of bacterial speck disease,
caused by
Pseudomonas syringae
pv.
tomato
,
in tomato plants treated with pyraclostrobin
was assessed in three independent experi-
ments. Moreover, the effect of pyraclostrob-
in against
Cucumber mosaic virus
(CMV) and
Potato virus Y
(PVY) was assessed in an en-
vironmentally controlled greenhouse, as
well as in field trials in commercial (toll type)
greenhouses. Disease incidence and devel-
opment was affected by pyraclostrobin ap-
plication in all experiments conducted so far
and further verification of results and analy-
sis is in progress. In a second set of experi-
ments, the elicitation of defence responses
by pyraclostrobin, as indicated by a poten-
tial increase in the transcription of systemic
acquired resistance (SAR)-linked genes, was
assessed.
Chemical control of grey mould on lettuce grown in hydroponic systems
and fungicide residues at harvest
M. C
HATZIDIMOPOULOS
1
, I. L
IGAS
2
and A.C. P
APPAS
1
1
University of Thessaly, Department of Agriculture Crop Production and Rural
Environment GR-384 46 N. Ionia Volos, Greece.
2
Cadmion Analytical Laboratory, E.
Antistaseos 153, GR-202 00 Kiato Korinthias, Greece
For two consecutive years (2010, 2011) the
effectiveness of various fungicide spray ap-
plications against grey mould on lettuce
grown in hydroponics, was evaluated. Two
standard applications were made at seed-
ling stage followed up by one or two more
sprays after transplanting, at 15-day inter-
vals. The last application was made at least
4 weeks before harvest. Applications at
the seedling stage with each of Daconil SC
(chlorothalonil 50%) 3ml/lt, Teldor WG (fen-
hexamid 50%) 1.5g/lt, Signum WG (boscalid
26.7% + pyraclostrobin 6.7%) 1.5 g/lt, Switch
WG (fludioxonil 25% + cyprodinil 37.5%)
0.5g/lt and Ortiva Οpti SC (azoxystrobin 8%
+ chlorothalonil 40%) 2.5ml/lt, reduced sig-
nificantly the disease incidence and severity,
compared to untreated controls. The fungi-
cides Switch WG and Signum WG provided
the best control, whereas Teldor WG and Da-
conil SC were the least effective. The level of
the disease was further reduced with one or
two more fungicide applications after trans-
planting. To avoid the development of re-
sistance, alternative fungicide applications
were found necessary. With the exception
of applications of Daconil SC (chlorothalonil
50%) after transplanting, in all other treat-
ments either no fungicide residues or resi-
due levels below acceptable European MRLs
were detected at harvest.
Biological activity of the succinate dehydrogenase inhibitor fluopyram
against
Botrytis cinerea
and fungal baseline sensitivity
T. V
ELOUKAS
and G.S. K
ARAOGLANIDIS
Plant Pathology Laboratory, Faculty of Agriculture, Aristotle University, Thessaloniki,
Greece
