Grapevine (Vitis vinifera L.) quality and growth are affected by the foliar fertilization. Algae extract, glutamic acid, and vitamin B
are known as foliar fertilizer but there is little information available about the best combinations of these materials for grapevine.
Here, 2-year field study in a randomized complete block design (RCBD) were conducted to study the influence of foliar
applications of vitamin B, glutamic acid, and algae (Amphora ovalis) extract on Thompson Seedless grapevines (Vitis vinifera
L.) growth and yield. The growth, yield, and quality of grapevine were affected significantly (P < 0.05) by the different treatments. The foliar application of vitamin B, glutamic acid, and algae increased the pruning wood, total chlorophyll, leaf area, and
fruit yield compared with the control. In addition, these treatments induced an increase in the concentrations of N, P, and K. The
berries quality characteristics of the sprayed vines were significantly better than non-treated ones. Based on the obtained results,
the foliar application of glutamic acid, vitamin B complex, and algae besides of their combinations has positive effects on the
growth of grapevine plants and berry quality.