Gibberellic acid and nitrogen rate affect yield and quality of artichoke

The aim of this study was to evaluate the effect of nitrogen fertilization and GA3 treatment on growth and yield of globe artichoke for spring production. The research was carried out in Salerno’s area (40° 39' N) on vegetative propagated plants, transplanted on October, 6 on clay-loam soil. Four nitrogen rates (0, 100, 200 and 300 kg/ha) and four GA3 concentrations (0, 30, 60 and 90 mg L-1) were compared using the roman artichoke ‘Castellammare’. Nitrogen fertilization promoted the earliness and increased the yield, with remarkable effects on the weight of the main heads as well as on the number and the weight of the secondary heads. The best productive results were obtained using 200 kg/ha (15.0 vs 11.0 t ha-1 in the non-fertilized control). Compared to the control, GA3 treatment determined an earlier production (-7 days in plants under 60 and 90 mg L-1) and higher total yield (from 12.2 to 13.7 t ha-1 under 90 mg L-1), by increasing the number of both secondary and industrial heads, while reducing the weight of main and secondary heads.