Foliar Application of Liquid Micronutrient Formulation for Improving Quality of Panner Grapes

Micronutrient deficiencies play a significant role in impacting the yield and quality of grapes in vineyards. To address the deficiencies, a field study was conducted during the summer, of 2022 by using foliar micronutrient mixtures in three different concentrations (0.5%, 1.0%, and 1.5%), with one spray during pre-fruit set stage and twice at pre-fruit set/berry growth stages. The study aimed to investigate the effects of foliar micronutrient application on the biochemical quality characteristics of the Muscat Hamburg grapevine cultivar. The results of the study showed that the application of micronutrients spray showed a beneficial impact on all the yield parameters, such as number of bunches per vine (ranging from 28 to 44), the yield per vine (varied from 5.56 to 6.55 kg per vine), with overall yield range between 20.7 to 24.2 t ha-1. The biochemical properties of the berries, including sugars (reducing, non-reducing, and total sugars), juice pH and content, TSS (Total Soluble Solids), Titrable acidity, and berry firmness, were found to be high in grapevines sprayed at 1.0% twice. Results showed that total sugars ranged from 15.2% to 10.7%, with a juice pH of 3.47 to 3.94, juice content of 83.5 to 95.5%, and TSS from 15.6 to 17.40º Brix. Regarding the Titrable acidity and firmness of the berries, the outcomes showed a range of 0.92% to 1.14% for acidity and 9.4 to 12.9 N for firmness. Findings from the study clearly showed that applying 1.0% micronutrients twice at fruit-set and berry stages increased yield and improved quality indices of Paneer grapes.