[Edited_by_A._Ciancio,_C.N.R.,_Bari,_Italy_and_K.(Bookos.org)

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F. KARAMAOUNA ET AL.
Alexandrakis, 2007). Results of the second release site differ. Th e exoti c parasitoids
C. phyllocnistoides and S. petiolatus were recovered whereas Quadrastichus sp. was not
recovered (Tsagarakis et al., 1999). Although the population of C. phyllocnistoides
increased with time after the release, the exotic parasitoid did not displace the native
species N. formosa and P. pectinicornis. Neochrysocharis formosa was the most
abundant parasitoid for a period of 3 years after the release (Tsagarakis & Lykouressis,
2002; Tsagarakis, Kalaitzaki, Lykouressis, Michelakis, & Alexandrakis, 2003).
Citrostichus phyllocnistoides has been found in almost all citrus producing areas in
Greece (Kalaitzaki, 2004).
The parasitoids Pnigalio sp., Cirrospilus sp., N. formosa and C. phyllocnistoides
were collected at the areas of Marathonas-Attiki, Galatas-Trizinia and Skala-Lakonia in
1999–2000 (Anagnou-Veroniki, Doukas, & Kontodimas, 2002), Pnigalio pectinicornis
and Cirrospilus sp. were collected on the islands of Lesvos and Chios and in western
mainland, as were N. formosa and C. phyllocnistoides (Papanikolaou, 2005).
The list of native parasitoids expanded with the first recording of Pnigalio soemius
(Walker) (Hymenoptera: Eulophidae) (Papanikolaou, 2005; Papanikolaou,
Kavallieratos, Kontodimas, & Tomanovic, 2006) and Semielacher silvicola Boucek
(Hymenoptera: Eulophidae) in Attica, in 2005 (Vamvakas, Anagnou-Veroniki, &
Kontodimas, 2005).
2.4.3. Cultural Practices
Cultural measures advised involve some changes of the standard management practices
in order to prevent or make the environment less favorable for the pest reproduction,
dispersal and/or survival. Decrease of fertilization and irrigation inputs should moderate
the susceptibility of the new flush to the citrus leafminer during summer when the pest
is very active. Moreover, fertilization, irrigation and pruning should be regulated to
enhance discrete flush patterns over large areas, breaking generations overlap
(Anagnou-Veroniki, Volakakis, & Gianoulis, 1995; Michelakis & Vacante, 1997).
2.4.4. Chemical Control
The application of insecticides to control the citrus leafminer is proved to be a
short term solution especially for plant nurseries and newly grafted trees which
suffer more from the pest infestation.
The insecticides (active substances) which were initially recommended were
fenoxycarb and diflubezuron in combination with summer oils. Only the external part
of the trees, where the flushes and hence the citrus leafminer infestation occurs,
should be sprayed with the solutions. Fenoxycarb showed no killing effects on
C. noacki, the parasitoid of A. floccosus (Buchelos & Foudoulakis, 2000). Later on
more selective insecticides i.e. chlorfenapyr, abamectin, flufenoxuron, azadirachtin,
summer oils etc. were used (Michelakis & Vacante, 1997).
Other insecticides added in the list were acephate, diazinon, dimethoate,
methomyl, phospanidon, fenvalarate whereas their side effects on the natural
enemies of the pest were illustrated (Anagnou-Veroniki et al., 1995).