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

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F. KARAMAOUNA ET AL.
cultural practices. Conservation of aphidophagous insects is achieved mainly by
avoiding the use of selective insecticides, especially in overall cover-spray
treatments (Katsoyannos, 1996a).
2.6. The Citrus Flower Moth, Prays citri
The citrus flower moth Prays citri usually completes three generations in Greece
whereas development time is estimated to range from 15 to 19 days in the region of
Achaia-Peloponnese (Buchelos et al., 1963; Tzanakakis & Katsoyannos, 2003).
The adults of the first generation appear in August and those of the second
generation in October–November. Maximum infestation on lemons is observed at
the end of their main florescence whereas the next generations of the pest infest the
flowers and fruits of the subsequent florescences of multiple-flowering lemon trees
(Buchelos, Sueref, & Tsoka-Thanasoulopoulou, 1963). The major damage concerns
the citrus flowers and the newly formed fruits and it is more severe in lemons and
citrons. In addition, serious damages have been reported on new overgraftings at
warm regions in autumn (Tzanakakis & Katsoyannos, 2003).
Control of the pest depends largely on cultural practices and methods directed
against the adult moths, since the larvae mining within the flower tissues are not
normally vulnerable to insecticides and insect pathogens.
2.6.1. Sampling and Monitoring
Monitoring of infestation is possible by sampling and examination of flowers and
newly formed fruits (Cavalloro & Protta, 1983). Synthetic sex pheromone Z-7-
tetradecenal is available in the US for monitoring (Mineo, Mirabello, del Busto, &
Viggiani, 1983; Benfatto, 1984) or mass-trapping (120 traps/ha) of males
(Sternlicht, Barzakay, & Tamim, 1990).
Although no correlation exists between trap catch and level of flower damage
(Mineo et al., 1983; Benfatto, 1984) as males of overlapping generations of the
pest are caught throughout the growing season, both samples and trap captures are
taken into account for accurate timing of chemical application on citrus (mainly
lemon and citron) when required.
The threshold of flower damage by P. citri for chemical control is estimated at
>50% of flowers infested whereas in the case of fruits when 3% are affected
(Cavalloro & Protta, 1983). A percentage of 20–30% of healthy flowers is
sufficient for a satisfying production in lemons (Katsoyannos, 1996b).
2.6.2. Biological Control and Cultural Practices
Prays citri has several natural enemies, principally parasitoids e.g. Ageniaspis
fuscicollis (Dalman) subsp. praysincola Silvestri (Hymenoptera: Encyrtidae) and
Elasmus flabellatus Boyer de Fonscolombe (Hymenoptera: Eulophidae), which are
not always effective in contoling the pest (Tzanakakis & Katsoyannos, 2003).