INTEGRATED STRATEGIES TO MONITOR AND CONTROL CITRUS FLOWER MOTH, PRAYS CITRI (LEPIDOPTERA: YPONOMEUTIDAE) ON NURSERY TREES OF THE MEDITERRANEAN AREA

Prays citri (Milliere) (Lepidoptera: Yponomeutidae), citrus flower moth (CFM) is regarded as a key pest of nursery trees in Sicily. The larval activity causes damages to flowers and new shoots. In addition, the young larvae can penetrate the small fruits. The growers may spray several times per year prevalently with organophosphate insecticides. Starting from 2006 a new IPM approach was evaluated: we carried out experimental trials of different chemical compounds and tested the possibility of timing the insecticide applications by means of monitoring the male flights with pheromone traps. In the years 2007, 2010 and 2011, the efficacy of fosmet (organophosphate), flufenoxuron (Insect Growth Regulator) and Bacillus thuringiensis var. kurstaki, was evaluated on young lemon trees. The results, previously published, suggested that OPs could be substituted, or at least alternated, with IGRs and Bt for the control of CFM. Starting from 2006, pheromone (Z-7 tetradecenale) traps were placed for six years in two lemon nurseries, and the infestation level on flowers, young fruits and new shoots was recorded. The first plot (nursery located in Messina province) was subjected to an intensive spray program; the second plot (nursery located in Catania province) was submitted to a very low impact spray program. Only the data obtained in the Catania nursery produced a positive linear correlation between male captures and infestation percentage. Depending to economic target pursued, growers can themselves establish a maximum level of captures as an alert threshold.