Control of dieback ("Moria") of Corylus avellana in central Italy using copper compounds

Bacterial dieback of hazelnut (Corylus avellana), commonly called moria is the most serious problem in hazelnut orchards in Central Italy. Various copper compounds (copper oxychloride, tribasic copper sulphate with or without addition of a leaf fertilizer, and copper sulphate pentahydrate) were tested in areas affected by the disease, and all gave effective control. Copper oxychloride and tribasic copper sulphate, in combination with a leaf fertilizer performed best, but copper sulphate pentahydrate containing a very low concentration of copper (55 g/l), still gave sufficient protection.