This research was conducted during 2019 & 2020 seasons in Afak farm located at Balat district, New Valley Governorate. To evaluate the effect of some horticultural practices treatments to tolerant heat stress on vegetative growth, yield and berry quality of Flame Seedless grapevines. The experiment was set up in a complete randomized block design with eleven treatments, using three replicates, two grapevines each.
It could be summarized the current results are as follow:
- The weight of pruning wood and leaf area as well as leaf potassium and proline contents were significantly increased due to spraying any potassium or amino acids sources or vine shading and clusters pagging comparison with untreated ones (check treatment). In most studied traits no significant differences were recorded between using any treatment compared to other.

- Also, using any previous treatments or cluster pagging increased yield and improved berry quality compared to untreated ones. In general, using thiosulfate or amino acids gave the highest values of these studied traits.
- The foregoing results indicated the vegetative growth and fruiting traits significantly improved du to potassium and amino acids sources spraying, as well as , it minimized the harmful effects of heat stress.