Page 13 - Volume 1, Issue 2, July 2008

New plant pests and weeds in Greece 65
first appeared in 1983. The insect devel-
ops at high numbers especially on young
trees on which it may feed on the leaves
causing a complete defoliation.
1.8. Concluding remarks
More than 70 insect species, mostly
Hemiptera-Homoptera, have been record-
ed for the first time in Greece since 1990.
The woolly whitefly Aleurothrixus floccosus
and the citrus leaf-miner Phyllocnistis citrel-
la, both serious citrus pests of worldwide
importance, are invasive species and their
control relied on clasical biological control
programmes by introducing exotic parasi-
toids that were proved to be highly effec-
tive. Other species of the newly reported
pests that are considered important are:
the thrips Pezothrips kellyanus and Franklin-
iella occidentalis , the red palmweevil Rhyn-
chophorus ferrugineus, the gall inducing
wasps Ophelimus maskeli and Leptocybe in-
vasa and the asparagus pests Parahypopta
caestrum and Hexomyza simplex. Several of
the new recorded species are of palearc-
tic origin but their presence in Greece had
not been documented so far. It is impor-
tant in concluding to note that, because of
the serious threats imposed by the inva-
sive species, there is always the need for a
thorough survey to early detect potential
new invaders and for an organized rapid
reaction upon their detection.
2. Phytophagous mites
New records of phytophagous mites be-
longing to the families of Tetranychidae,
Eriophyidae and Tenuipalpidae have been
reported from Greece, during the period
1990-2007, and are summarized in this ar-
ticle. Three species, namely Aculus olear-
ius Castagnoli (Papaioannou-Souliotis,
1982), Eriophyes (Aceria) paradianthi (Keif-
er) (Papaioannou-Souliotis, 1987) and Phy-
tocoptella yuccae (Keifer) (Papaioannou-
Souliotis, 1993), although recorded before
1990, are also included here because an
outbreak of their population has been re-
cently observed and they are now consid-
ered to cause high economic damage. The
reported species are discussed arranged
by family in the text and listed alphabet-
ically with their hosts in Table 2.
2.1. Tetranychidae
The citrus brown mite Eutetranychus
orientalis (Klein) was first recorded in
Greece, in the area of Helleniko (Prefec-
ture of Attica), on lemon and orange trees,
in autumn 2001 (Papaioannou-Souliotis &
Markoyiannaki-Printziou, 2002). E. orien-
talis is a serious pest of citrus, more detri-
mental than Tetranychus urticae Koch and
Panonychus citri (Mc Gregor). It mainly af-
fects lemon and orange trees and to a less-
er extent mandarins. Feeding generally
starts on the upper side of the leaf along
the midrib and then moves to the lateral
veins. As a result, leaves become chlorot-
ic and yellow streaks develop along the
veins. Heavy infestationmay cause leaf fall,
die-back of branches and defoliation. Until
now there are no data on chemical control
or other kind of management measures.
The red spider mite Tetranychus evansi
Baker and Pritchard is of South American
origin and has been introduced into oth-
er parts of the world (Northern and South-
ern Africa, Spain, Portugal). T. evansi tends
to prefer solanaceous crops: tomato, au-
bergine (eggplant), potato, tobacco, but it
can be found on several other crops (e.g.
beans, citrus, cotton, castor bean) and or-
namental plants (e.g. Rosa sp.), as well
as on many weed species. It was first re-
corded in Greece, in the area of Tympa-
ki (South-Central Crete) on Solanum ni-
grum in September 2006 (Tsagkarakou et
al., 2007). Damage is similar to that caused
by other spider mites. Feeding punctures
lead to whitening or yellowing of leaves,
followed by desiccation and eventual-