Effetti delle epoche e modalità di concimazione su produzione e qualità del finocchio. Effects of time and method of fertilizer application on yield and quality of fennel.

Two field trials were carried out in Sicily during fall-winter and spring season to determine the influence of 9 fertilization treatments, obtained by changing the time (pre-plant and/or post-plant fertilization), and method (broadcast fertilization and/or fertigation) of fertilizer application and the type of fertilizer (mineral, organic, slow release fertilizers) on yield and quality of fennel. An unfertilized treatment (control) was also included. In all fertilized treatments, macronutrients were applied at the following total rates (kg ha-1): N (350), P2O5 (100), K2O (208). In both trials the highest yield and mean bulb weight was obtained by pre-planting application of all mineral fertilizers (51,5 and 78,4 t ha-1 in fall-winter and spring growing cycle, respectively). The lowest nitrate content have been recorded in pre-plant fertilized fennels and in those fertilized with a slow release fertilizer, while the highest value has been observed in fertigated fennels.