Relationship of nutritional balance index (nbi) with yield and quality indices of grape

In order to evaluate the relationship of nutritional balance index (NBI) with yield and quality characteristics of grape, a four year experiment was conducted in Kohgiluyeh-va-Boyerahmad province. The purpose of this study was to determine the nutritional elements balance status and its effect on yield and quality of grape in orchards. In this experiment, DRIS norms were established first for grape. The established norms were then used to calculate DRIS indices and nutritional balance index for those orchards having low yields. Beside, exponential regression analysis was used to evaluate relationship of NBI with yield and quality characteristics of grape. The results showed a negative and significant (at 1% probability level) relationship between NBI and yield. Relationships of NBI with sugar, TSS and TSS/TA were negative that the latest case was significant at 5% probability level. Relationship between NBI and TA was positive but not significant. Based on the obtained results, the amount of NBI was high that expressed the imbalanced status of elements the most important factor in reduced grape yield and quality in orchards