Effects of organo-mineral fertilizers on yield characteristics of globe artichoke

The recent widespread availability in Europe of organo-mineral fertilizers would seem to open up new prospects in so far as they can represent an alternative to mineral fertilizers. To study the effects of organo-mineral fertilizers on earliness and yield characteristics of two globe artichoke (Cynara cardunculus L. var. scolymus (L.) Fiori) genotypes, a field experiment was carried out during two growing seasons. Three fertilization treatments, including supply with 222-162-154 kg ha-1 of N, P2O5 and K2O, respectively, utilizing mineral fertilizers (T1) or organo-mineral fertilizers (T2) and nitrogen reduced supply 166-162-154 kg ha-1 of N, P2O5 and K2O utilizing only organo-mineral fertilizers (T3), were studied. Genotypes were the traditional vegetative propagated 'Violet de Provence' and the modern seed-propagated 'Opal F1'. Results show that, compared to mineral fertilizers, organo-mineral fertilizers, above all at nitrogen reduced level (T3), improved earliness, expressed as the number of heads harvested at the end of December, in both genotypes and in both growing seasons. The effect on head yield was cultivar and season dependent. In fact, organo-mineral fertilizers did not show significant differences in 'Violet de Provence', whereas they slightly reduced yield in 'Opal F1'. In addition, they decreased yield by 16% in the first growing season, but increased it by 6% in the second growing season.