Effect of different pruning methods on growth, yield and quality of the Hazelnut cultivar “Tonda Gentile Romana"

In Central Italy (Latium region) the pruning of hazelnut is done during the winter when trees are dormant, and it is limited to little interventions of cleaning of the canopy and removal of old branches and suckers. In order to study the effect of different pruning methods on cv. “Tonda Gentile Romana”, two thesis, respectively based on low (thesis A) and high (thesis B) intensity pruning, were carried out and compared whit an un-pruned thesis from 2004 to 2006. Wood removed, vegetative growth, light infiltration at the base of the plots, yield and nut traits, defects and kernel quality were measured, in order to quantify plant response to different intensity of pruning in a medium-vigour cultivar. The results indicate good productivity and vegetative growth in the thesis B at the end of the three years, and yield per hectare slightly decreased only in the first year with respect to thesis A. Light infiltration at the base of the plants was low in un-pruned plots, whereas thesis B was characterized by better light penetration. The intensity of pruning had only a slight effect on nut traits and content and profile of oil, sugars and organic acids.