Applicazioni di metodi biotecnici per il controllo della carpocapsa in frutteti a conduzione biologica nel Parco dell’Etna

Semiochemical applications for the control of the codling moth in organic fruit orchards in Etna Park The results of experiments conducted in 2006-2008 in pear and apple orchards situated in the territory of the Etna Park are reported. The main objective of the trials was to evaluate, in this particular ecological context, the feasibility and effectiveness of two techniques of mating disruption: the false-trail-following and the auto-confusion for the control of the codling moth, Cydia pomonella L., key pest of these crops. Tests were conducted in two organic farms in Ragalna and Zafferana municipalities, in the province of Catania; the experimental fields had different agronomic and ecological characteristics. For the false-trail-following technique, 2500 pheromone dispensers were applied for each field; as for the application of the auto-confusion technique, special traps have been installed at the rate of 30 units/ha. The surveys carried out have shown infestation levels in the two orchards varying from 6 to 35.5%. Overall analysis of data confirms the applicability of the false-trail-following technique in the orchards of Etna Park but it highlights the need, in unfavorable agro-ecological conditions and in the case of high-density, of integration with microbiological (granulosis virus) control aimed at reducing initial populations of the pest. In the orchard treated with the auto-confusion technique, in spite of the relative reduction of adult captures in the control trap, infestation ranged from 12.7% to 37.8%. Therefore, this technique has not produced acceptable results, despite being integrated with microbiological interventions. During the trials, occasional infestations of the apple aphid Dysaphis plantaginea (Passerini), were recorded; to control the apple small ermine moth, Hyponomeuta malinellus Zeller, widespread pest in the investigated fields, it was necessary to apply specific microbiological treatments. No infestations of other pests such as pear psylla, spider mite and leaf rollers were recorded.