Biological Control of Hazelnut Weevil (Curculio nucum L., Coleoptera, Curculionidae) Using the Entomopathogenic Fungus Beauveria bassiana (Balsamo) Vuill. (Deuteromycotina, Hyphomycetes)

The need to biologically control phytophagous insects has led researchers to consider using microorganisms to control insect pests in the field. On this basis, we decided to conduct field tests to determine the effectiveness of a commercial product made of Beauveria bassiana (Bals.) against the key hazelnut pest Curculio nucum L. Trials were carried out in a hazelnut orchard in the province of Viterbo (Italy). Three untreated control cages and three cages treated with the fungus entomopathogens were used during the tests. The cages were located under the hazelnut canopy and buried to half their height. 200 mature C. nucum larvae were placed in each cage and allowed to burrow naturally. After the larvae had buried themselves, a commercial product was applied to the three treated cages. Mortality was monitored during the following spring. The treated cages showed 99.5% C. nucum mortality as opposed to 63.5% for the untreated cages. These data show the effectiveness of the B. bassiana biological control on key insect pests for hazelnut trees in central Italy.Research partially financed by Mi.P.A.F. Project “Studio e ottimizzazione della filiera coricola dell’area Cimino-Sabatina” D.M. 564/7303 10/11/2003