Effect of amino-fertilizer on berries growth of Lebanese traditional table grape

Amino acids can directly or indirectly influence the physiological activities responsible for plant growth and development. The foliar application of amino acid fertilizers on grapevine increased its yield and enhanced the vegetative growth of vines. Consequently, the current study aimed to investigate the effect of amino nano-fertilizer (Biozar Amino Ca) on berries growth of the traditional table grape cultivar ‘Tfiefihi’. Biozar amino fertilizer was applied twice via two concentrations. Experimental treatments were: conventional fertilizer (control), Biozar Amino Ca 3 g L^‑1, and Biozar Amino Ca 5 g L^‑1. Veraison date, average weight and diameter of 20 berries, titratable acidity (TA), pH, and juice content were the recorded indicators. Compared to control, the application of Biozar Amino Ca 3 g L^‑1 delayed veraison dates by 5 days, while Biozar Amino Ca 5 g L^‑1, hastened veraison by 4 days but was not significantly different. Biozar Amino Ca decreased average weight of 20 berries by 13.3 and 8.54 g when applied in 3 and 5 g L^‑1, respectively; however, differences were statistically not different between treatments. Berries’ diameter and titratable acidity were comparable between all treatments. Biozar Amino Ca 3 g L^‑1 recorded the lowest pH (3.87) compared to the control and T3. The absence of significant effect of amino nano-fertilizer could be related to the timing of products applications, which could perhaps have a significant impact if applied maybe earlier during the vegetative stage.