Strategie di controllo di Bactrocera oleae (Rossi) con metodi alternativi agli interventi convenzionali in oliveti biologici della Sicilia occidentale

This work reports studies on the population dynamics and safe control strategies of Bactrocera oleae in four unsprayed olive groves of western Sicily from 2007 to 2010. The main management tools for B. oleae evaluated were the“Attract and Kill” lures (Ecotrap Vioryl), the use of sardines (traditional practice) and Nu-lure (innovative) and the spinosad (innovative) which is a selective insect control product produced by the fermentation of a naturally occurring soil bacterium, Saccharopolyspora spinosa. Flies trend were carried out by pheromone traps and the level of infestation counting the number of fruits with pest eggs, larvae and pupae and hole hatching. Results showed that in all olive groves and during three years of observation, the number of males caught by pheromone traps and infestation levels in the control areas were often higher than in the treated areas with baits. The lowest values were always detected in areas with sardine and Nu-lur baits. The infestation was always lower in the area treated with spinosad than in untreated area (control). The number of healthy olives from the areas treated with spinosad was on average 70%. The assessment of these ecological methods induces their application as control strategies with the aim of reduce the olive fruit fly population below economic threshold considering the low environmental impact.