The nutraceutical response of two globe artichoke cultivars to contrasting NPK fertilizer regimes

Globe artichoke contributes to the healthiness of the Mediterranean diet, but its nutraceutical value in response to its agronomy has not been investigated in any detail to date. Here, the effect of two contrasting fertilizer regimes (one balanced and the other excessive) on the sugar, ascorbic acid and total polyphenol content, the polyphenol profile and the antioxidant activity of the two cultivars 'Apollo' and 'Tema 2000' were monitored in plants grown in three locations in Sicily ('Landolina', 'Iannarello' and 'Zotto'), which contrasted for soil type. The balanced fertilizer regime favored the content of sucrose, inulin, ascorbic acid and polyphenols (in particular that of 1,5-di- and 5- O-caffeoylquinic acid, along with apigenin 7- O-glucuronide). It was also more supportive of a high antioxidant activity. There was a pronounced cultivar and trial location effect, especially in terms of the accumulation of antioxidant compounds. Plants grown at 'Landolina' responded more strongly than at the other two locations to the fertilizer regime with respect to both ascorbic acid and total polyphenol content. The conclusion was that providing a balanced supply of nitrogen/phosphorus/potassium (NPK) via fertilizer application can enhance the nutraceutical value of globe artichoke, although the effect is modulated by both genetic factors and soil type.