Page 11 - Volume 6, Issue 1, January 2013

© Benaki Phytopathological Institute
Eriophyoids in Greek orchards and grapevine 9
Fruits that are fully developed before the
mites become abundant do not show much
damage. The species overwinters under the
stellate hairs of the leaves and migrates ear-
ly in spring in the flowers where it stays until
the fruit is formed.
In Greece, this mite appears very fre-
quently in high population densities main-
ly in regions with mild winters and humid
summers. In many cases it is found associ-
ated with A. benaki, D. athiasella , T. hassani
(Hatzinikolis and Kolovos, 1985), and it is
considered an occasionally serious pest.
Aceria olivi (Zaher and Abou-Awad) [Erio-
phyes olivi Zaher and Abou-Awad]
Damage: The mite forms characteristic
concave patches on the undersides of the
leaves, and may cause malformation to the
succulent terminal leaves (Zaher and Abou-
Awad, 1979). It is not considered of impor-
tance in Greece as its distribution is quite
limited (Hatzinikolis and Kolovos, 1985).
Aculops benakii (Hatzinikolis) [Aculus
benakii Hatzinikolis]
Common name: olive yellow spot mite
Damage: It lives on the underside of olive
leaves under the stellate hairs. As a result
the stellate structures drop off, making yel-
low leaf spots.
In Greece it has been found mainly in
coastal areas, with mild winters and relative-
ly cool and humid summers. It attacks leaf
and flower buds, flower and young fruits.
It is of great economic importance in olive
growing locations in Western Greece, Crete
and Lesvos (Hatzinikolis and Kolovos, 1985).
Aculus olearius Castagnoli
Damage: It is found only in the inflorescenc-
es from the emergence of the flower buds to
the setting of the fruit. It causes the brown-
ing and withering of the flower and small
fruits. It is not considered of importance in
Greece as its distribution is quite limited (Pa-
paioannou-Souliotis et al ., 1994).
Ditrymacus athiasella Keifer
Damage: It produces some leaf pitting, de-
formation and discoloration. It is usually
found on the upper surface of young leaves,
the flowering buds and small fruits (Hatz-
inikolis, 1982) and for a short period of time
on flowers (Castagnoli and Papaioannou-
Souliotis, 1982) and older leaves (Castagno-
li and Pegazzano, 1986). It usually coexists
with the other eriophyids and it is difficult to
estimate the damage caused by this single
species. Hatzinikolis (1982) reported defor-
mation of leaves and flower and young fruit
dropping due to the bud infestations.
Ditrymacus athiasella attacks on the
buds causing malformed leaves and inflo-
rescences that fall off before full develop-
ment. On the leaves, mite attack is evident
from the appearance of yellow-white spots
on their upper surface which correspond
with swellings on the lower surface. Attacks
on the flowers result in drying and fall of
flowers together with the secondary axes of
inflorescences. Infestation of the fruits takes
place only during the first stages of devel-
opment, leading to premature drop of the
fruits (Hantzinikolis, 1984). It has caused
economic problems in Argolis and Arcadia
(Hatzinikolis, 1991) and reported to occur in
great population densities causing econom-
ic damage in the olive oil producing areas of
Peloponnese and central Greece.
Oxycenus maxwelli (Keifer) [Oxypleurites
maxwelli Keifer]
Common name: olive leaf and flower mite
Damage: O. maxwelli feeds preferentially on
the upper surface of terminal leaves, but in
high infestations it also feeds on the lower
leaf surface, buds, new shoots, flowers and
stems (Jeppson et al., 1975). Heavy infesta-
tions may cause premature flower drop as
well as leaf spotted discoloration and dis-
tortion. High infestation of the mite on
young leaves can cause silvering and distor-
tion, which reduces light absorption and de-
creases photosynthesis. Another problem
attributed to infestations by O. maxwelli is
the reduction in internodal length, leading
to the formation of overbudding (bunch-
top). In young plants, bud infestation can
lead to deficient plant growth (Castagno-