Comparison of DOP and DRIS Methods for Leaf Nutritional Diagnosis of Vitis vinifera L., Cv. Tempranillo

Deviation from optimum percentage (DOP) and Diagnosis and Recommendation Integrated System (DRIS) are methodologies for leaf analysis interpretation. DOP calculates the deviation as a percentage for each essential element while DRIS calculates the average deviation for different ratios that include each element. A vine survey was undertaken for 11 years in La Rioja, northeastern Spain, to establish nutritional references for cv. ‘Tempranillo’ (Vitis vinifera L.). Diagnosis of nitrogen, phosphorus, potassium, calcium, and magnesium were performed by DRIS and DOP on the dataset for leaf blade and petiole, at both flowering (n = 684) and veraison (n = 801) with a moderate-yield criterion (3,800–10,000 kg·ha). Important differences between DOP and DRIS were found when a diagnosis using the same dataset was performed. In spite of the differences, the regression equations obtained are an acceptable adjustment between both methods for phosphorus (P) and magnesium (Mg) in blades and petioles, and for potassium (K) in blades.This study was supported by the National Institute of Agricultural Research (Spain), the European Social Fund, and the Regional Government of La Rioja (Spain) Projects INIA-SC00-016, PR-01-03, PR-01-04, and PR-03-05, among others.Peer Reviewe