Monitoring οlive fly Bactrocera oleae (Diptera: Tephritidae) activityin an organic table olive orchard in Crete, Greece

Abstract: The activity of Bactrocera oleae and other invertebrate groups were monitored in atable olive orchard in the Messara plain, southern Crete, Greece throughout the olive seasons2006, 2007 and 2008 using McPhail traps. Sampling was carried out weekly between Februaryand November, with a total of 120 samples being collected over the 3 years. In addition, 2 bottlebased(Pepito and Elkofon) and one envelope type (Vioryl) mass trapping systems werecompared with respect to (a) their efficacy of controlling the olive fly between May andNovember and (b) impacts on non-target invertebrates.Multivariate analyses were carried out using a range of climatic factors (temperature,rainfall, humidity and wind direction) as drivers and the activity of olive fly and the main groupsof flying invertebrates as response variables. Temperature, west and north wind, rainfall andhumidity were identified as significant drivers for the main flying insect groups caught inMcPhail traps. Results are discussed in the context of production practices, vegetation typessurrounding commercial olive orchards and climatic conditions in the Messara plain. There wasalso a trend towards south wind being a driver, while east wind was not identified as a significantdriver. When the bottle-based mass trapping systems were compared, the Pepito trap showedsimilar activity with respect to olive fly, but had a greater impact on non-target invertebratescompared to the Elkofon trap.