© Benaki Phytopathological Institute
Abstracts - 16th Hellenic Phytopathological Congress
29
O
RAL
& P
OSTER
P
RESENTATIONS
Potato blackleg in Greece caused by
Dickeya
sp. biovar 3 (
D. solani
)
M.G. P
AGOULATOU
, P.F. S
ARRIS
*, E.A. T
RANTAS
, D.S. S
TAVROU
, K.B. S
IMOGLOU
, F.N. V
ERVERIDIS
and D.E. G
OUMAS
Technological Educational Institute of Crete, School of Agricultural Technology,
Department of Plant Sciences, P.O.Box 1939, GR-710 04 Heraklion, Greece. *Present
Address: The Sainsbury Laboratory, John Innes Centre, Norwich Research Park,
Norwich NR4 7UH, UK
During the years 2007 and 2011, significant
bacterial infections were observed in pota-
to crops (
Solanum tuberosum
cv. Spunta) on
the island of Crete in Greece. Similar infec-
tions were observed at Nevrokopi, Drama,
during the spring period of 2012 (cvs. Ban-
ba and Safari). Affected plants had black-
leg and rotting symptoms at the stem base,
brown discolouration of vascular tissues,
wilting and soft rot in daughter tubers. Dis-
ease incidence varied from 5%-50%. The
aim of this study was to identify the patho-
gen responsible for the blackleg disease iso-
lated from both of the above mentioned
regions. Isolations were made from symp-
tomatic tissues onto CVP (crystal violet pec-
tate) and NAG (nutrient agar glucose) media.
Single bacterial colonies having characteris-
tic pectinolytic activity (CVP) and/or “fried
egg” colonies (NAG) were sub-cultured, pu-
rified, and used for further characterisation.
Twenty five isolates were characterized as
Dickeya
sp. biovar 3 (syn:
Erwinia chrysan-
themi
,
Pectobacterium chrysanthemi
) based
on standard biochemical tests. These strains
were biochemically identical to the refer-
ence strain
Dickeya
sp. IPO2222, while bio-
chemically distinct from the related refer-
ence strain
Dickeya dianthicola
BPIC2098, a
pathogen of potato. Molecular analysis with
a) repPCR (BOX and ERIC fingerprinting), b)
specific primers for the PCR amplification of
the
pel
(pectate lyase) gene, and c) sequenc-
ing of the
dnaX
gene, revealed identical pro-
files among the isolated strains and the ref-
erence strain
Dickeya
sp. IPO2222; which
were clearly distinct from the those of relat-
ed species
D. dianthicola
BPIC2098,
P. caro-
tovorum
TEIC3036,
P. atrosepticum
TEIC3211
and other
Erwinia
spp. Koch’s postulates
were fulfilled by inoculation onto pota-
to plants and tubers and re-isolation from
the sites of observed typical disease symp-
toms. This is the first report of potato black-
leg caused by
Dickeya
sp. biovar 3 (
D. solani
)
in a region outside of Crete (Nevrokopi, Dra-
ma). As
D. solani
, species include very infec-
tious strains, further spread of the pathogen
in potato production in Greece is expected
to have a high economic impact.
Molecular characterization of
Pseudomonas viridiflava
strains from
several hosts
E.E. M
PALANTINAKI
, P.F. S
ARRIS
*, E.A. T
RANTAS
, F.N. V
ERVERIDIS
and D.E. G
OUMAS
Technological Educational Institute of Crete, School of Agricultural Technology,
Department of Plant Sciences, P.O.Box 1939, GR-710 04 Heraklion, Greece. *Present
Address: The Sainsbury Laboratory, John Innes Centre, Norwich Research Park,
Norwich NR4 7UH, UK
The pectinolytic species
Pseudomonas virid-
iflava
is characterized as a weak opportunis-
tic plant pathogen, with a wide host range,
causing foliar and stem necrotic lesions
and basal stem and root rots. In Greece this
pathogen has been reported as a disease
causal agent in a wide range of host plants
including celery, blitum, eggplant, acanthus,
