Page 5 - Volume 1, Issue 1, January 2008

New plant pathogens in Greece 3
terranea M. Fischer also cause esca disease
complex of grapevine.
A dramatic upsurge of esca disease oc-
currs the last years, not only in old but also
in young vineyards and also in other hosts
(olive, citrus, kiwifruit) in Greece (Elena et
al., 2003; Elena et al., 2006; Elena and Pa-
plomatas, 2002; Paplomatas et al., 2006;
Rumbos, 2001; Rumbos et al., 2006).
Fusarium  spp.
Fusarium oxysporum š
New formae speciales of Fusarium ox-
ysporum Schlechtend.: Fr caused severe
diseases to several crops.
Root-stem rot and wilt of cucumber
(Cucumis sativus L.) caused by Fusarium ox-
ysporum f. sp. radicis-cucumerinum Vakal.
were reported for the first time. The dis-
ease caused devastating losses in green-
house cucumber crops and within few
years it gradually spread in the major cu-
cumber producing areas of Crete and the
remaining Greece (Vakalounakis, 1996).
Fusarium oxysporum f. sp. cumini Prasad
and Patel is responsible for early pre-harvest
plant death which has resulted in severe
losses in cumin ( Cuminum cyminum L.) yield
in the island of Chios. The use of seeds from
healthy crops and the avoidance of cultiva-
tion of cumin in severely infested sites were
recommended (Pappas and Elena, 1997).
Mimosa [Albizia julibrissin (Willd.) Durazz.]
was found with symptoms of a wilt disease
caused by Fusarium oxysporum f. sp. perni-
ciosum Hepting and many trees were dying
or dead in Thessaloniki (Northern Greece).
In the more advanced stages of the disease,
dark sap exudations flowed out of bark cracks
(Skarmoutsou and Skarmoutsos, 1999).
Fusarium wilt of sweet basil (Ocimum
basilicum L.) caused by Fusarium oxyspo-
rum f. sp. basilici (Dridrariya) Armst. is now a
serious problem for the commercial crops
in Greece. Of 14 tested commercial basil
cultivars 6 out of 8 large-leaved cultivars
were resistant, while all 6 small-leaved cul-
tivars were susceptible (Biris et al., 2004).
A severe disease was observed on Ca-
nary Island palm (Phoenix canariensis Hort.
Ex Chab.) caused by Fusarium oxysporum f.
sp. canariensis first in Attica (Southeastern
Greece) and then in other counties. First
symptoms began on the mature pinnae at
the base of the plant, which became dry.
Initially the leaflets on one side of the ra-
chis died but eventually the entire plant
died (Elena, 2005).
Leaf yellowing and brown discoloration
caused by Fusarium oxysporum f. sp. nicoti-
anae (J. Johnson) Snyder and Hansen, was
observed in tobacco ( Nicotiana tabacum L.)
plants cv. Burley TN97 in Central Greece.
The pathogen was present in tobacco seed
batches imported in 2000 and 2001, which
indicates that the infected seed was most
probably the primary source of the dis-
ease in Greece (Tjamos et al., 2006).
Fusarium compactum š
Fusarium compactum (Wollenw.) Gor-
don caused foot rot of banana (Musa sp.),
grown under glass in Crete (Frisullo et al.,
1994).
Alternaria  spp.
Different new species or pathotypes of
the genus Alternaria were found to cause
diseases in Greek crops.
Leaf spot disease of cucumber and
melon (Cucumis melo L.) caused by Alter-
naria alternata (Fr.: Fr.) Keissler f. sp. cucur-
bitae Vakal. was recorded for the first time
in Crete (Vakalounakis, 1990a, b).
In the area of Marathon (Southeast-
ern Greece) many chicory (Chichorium sp.)
crops were infected by Alternaria sonchi
J.J. Davis (Grigoriou, 1992b) and severe in-
fection of carnation ( Dianthus caryophyllus
L.) petals by Alternaria dianthicola Neerg.
was observed in open-field crops of car-
nation (Grigoriou, 1996b).
A new proposed pathotype Alternaria
alternata f. sp. helianthina caused leaf spot
disease of sunflower (Helianthus annuus L.)
in Northern Greece (Lagopodi and Thanas-
soulopoulos, 1996).