Hazelnut is one of the most important orchards in central Italy (Viterbo province). More than eighty phytophagous insect pests adversely affect hazelnut orchards, but only a few of these, such as Anisandrus dispar F. (Coleoptera, Scolytidae), induce severe damage.
A bacterial disease (called moria) constitutes one of the main phytopathological problems of hazelnut plants in central Italy.
Two years ago, the Lazio Regional Government and local hazelnut cooperatives supported a research into the bio-ethology of A. dispar and its possible association with moria disease on hazelnut plants in Viterbo.
In 2003 and 2004 two experimental hazelnut areas were selected in the Capranica and Caprarola districts (Viterbo), where eighteen chemio-chromotrophic traps were installed to study the dynamic population of A. dispar and to catch live Scolytidae females.
Representative samples of live A. dispar females were used to isolate and identify the bacterial populations present both outside and inside the insects.
After two years 5,726 A. dispar females had been caught.
Of more than 1,400 live A. dispar females, 10% were submitted to microbiological analyses by morphological, physiological, biochemical and molecular techniques.
The populations of the main bacteria (by outside and inside) associated with the phytophagous were identified as Erwinia billingae, Brenneria quercina, Pantoea cedenensis and Pseudomonas spp.
Studies are currently in progress to: i) clarify the biological cycle of A. dispar; ii) identify the role (direct and/or indirect) of the insect respect to the epidemiology of moria disease; iii) carry on pathogenicity tests on bacterial isolates to prove their involvement in bacteriosis; iv) develop specific primers to identify the presence of these bacteria when associated with the insect and with asymptomatic hazelnut plants; v) verify the influence of environmental parameters on the biology of both the insect and the disease.
Bucini, D., Balestra, G.M., Pucci, C., Paparatti, B., Speranza, S., Proietti Zolla, C. and Varvaro, L. (2005). BIO-ETHOLOGY OF ANISANDRUS DISPAR F. AND ITS POSSIBLE INVOLVEMENT IN DIEBACK (MORIA) DISEASES OF HAZELNUT (CORYLUS AVELLANA L.) PLANTS IN CENTRAL ITALY . Acta Hortic. 686, 435-444
insect, scolytidae, bacteria, orchard, damage, plant pathology