Interaction effects of nitrogen and potassium fertilization on anthocyanin composition and chromatic features of tempranillo grapes

Abstract

A factorial experiment (3 nitrogen and 3 potassium fertilization doses) was carried out in a Tempranillo vineyard located in the 'Ribera del Duero' Apellation d'Origine area (Spain) in 2000. N and K supplies caused decreases in delphinidin and petunidin monoglucoside content in grape skins. High nitrogen doses increase L* coordinate and chroma of the skins. High potassium with unbalanced nitrogen supplies enhances hue and yellow component of colour. Possible effects of N and K fertilization on the copigmentation of anthocyanins are discussed. ©Vigne et Vin Publications Internationales.