© Benaki Phytopathological Institute
Hellenic Plant Protection Journal - Special Issue
20
ple, quick, and reproducible method which
allows both the identification of seven
F. ox-
ysporum
formae
speciales
and at the same
time their screening for variants. Our geno-
typing assay uses the combined information
of simultaneously acquired HRM data from
an unlabeled probe and the full-length am-
plicon. Finally, the completion of both reac-
tion and analysis in a closed tube saves time
by eliminating the separate steps and re-
duces the risk of contamination.
Molecular and phytopathological investigation of the role of the global
regulator of secondary metabolism
AcLaeA
in the mycotoxigenic fungus
Aspergillus carbonarius
M. I
LIADI
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
The filamentous fungus
Aspergillus car-
bonarius
is considered one of the main fungi
responsible for sour rot in grapes and for the
production of the carcinogenic mycotoxin
ochratoxin A. Recently, a novel gene named
laeA
that operates as a global regulator of
secondary metabolism was discovered in
several species of
Aspergillus
and
Fusarium.
Inactivation of the
laeA
gene leads to dis-
ruption of mycotoxin biosynthesis. The gene
laeA
encodes a nuclear methyltransferase
protein that is required for the expression of
secondary metabolite genes, while its pres-
ence is considered indispensable for myco-
toxin, antibiotic and mycelial pigment bio-
synthesis. BLAST analysis of the genome of
A. carbonarius
with the
laeA
gene of
A. nid-
ulans
resulted in the identification of an or-
thologous gene named
AclaeA
. The goal of
this study was to investigate the role of the
regulatory gene
AclaeA
in the physiology,
virulence and ochratoxinA production by
A.
carbonarius
in grapes by deleting this gene
from the genome of two wild types of the
fungus. Using PCR with specific primers, two
genome sequences located about 1000 bp
before the start and stop codon of
AclaeA,
respectively, were amplified and subcloned
into the vector pBluescript. Between these
two regions the geneticin cassette was sub-
cloned in order to replace the
AclaeA
gene
after transformation. The
AclaeA
deletion
construct was transferred to the binary vec-
tor pGKO2 and then introduced using the Ti
plasmid of
Agrobacterium tumefaciens
via a
double recombination event, into two wild
type strains of
A. carbonarius
. The evalua-
tion data on the morphological character-
istics and virulence experiments in red and
white grape varieties of
ΔAclaeA
mutants is
presented.
First report of
Diaporthe neotheicola
as pathogen causing shoot blight in
kiwifruit
T
H
. T
HOMIDIS
and E. E
XADAKTYLOU
Alexander Technological Education Institute of Thessaloniki, Department of Crop
Production, GR-574 00 Sindos, Thessaloniki, Greece
Kiwifruit is an important crop in Greece. Al-
though it is considered to be a crop with few
pests and diseases, new diseases have been
identified in the last few years.
In June 2009, shoots of the kiwifruit plants
(cvs “Hayward” and “Tsechelidis”) were
found to be wilted and blighted in many or-
chards of Episkopi, Naoussa (Imathia Prefec-
ture, Greece). Close examination of these
shoots revealed distinct dark cankers. Fun-
gal isolations were made on acidified potato
dextrose agar, and the species responsible
