Evaluation of nutritional status of squash by Compositional nutrient diagnosis (CND) method in Khoy region

Compositional nutrient diagnosis (CND) are important methods for interpretation of the results of chemical analysis and diagnosis of nutritional status of plants. In order to evaluate the nutritional status of squash (Lagenaria Vulgaris) through CND and to determine nutrient norms for this crop, 122 leaf samples were collected from squash fields of Khoy region and N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and B were analyzed. The squash fields were divided into two high and low yielding groups, based on mathematical and statistical methods and by additive function of variance ratio, then CND indices and norms were calculated. Results showed that there were significantly differences between high and low yielding fields in terms of nutrients concentration. Based on CND indices, potassium and zinc nutrients had the most negative indices. CND nutritional balance index of low yielding fields were greater than zero indicating nutritional imbalances in these fields.