Evaluation of Nutritional Status of Vineyards in East Azarbaijan Using DOP and CND Methods

Grape is one of the most important agricultural products in East Azarbaijan Province (Iran), which has the third highest production in the country. The nutritional status of high-yield plants can be a real criterion for assessing the growth and favorable nutritional status of the plant. For this purpose, 62 vineyards in Malekan District were selected. In all vineyards, composite soil sampling was carried out at depths of 0-30 and 30-60 cm and over 1364 physical and chemical analyses were done. At flowering time, composite leaf samples were taken of leaves facing the bunch of grapes; then, 682 plant analyses were carried out using suitable laboratory methods. During the harvest, yield was measured and determined by visiting each vineyard. Finally, the Deviation from Optimal Percentage (DOP) and Compositional Nutrient Diagnosis Index (CND) were calculated for each nutrient element. Based on the yields, the studied vineyards were divided into two groups of high and low yield and quality. The results of CND and DOP indices showed that zinc and copper deficiencies were more prevalent among microelements and phosphorous and magnesium deficiencies were observed among macro elements. The results showed that the vineyards of this region faced the deficiency of phosphorus, magnesium, zinc, and copper. These results can be applied to the area's vineyards to enhance the yield and quality of the grapes.