Salinity is one of the most critical crises worldwide that ultimately compromises future food security. Brassinosteroids including brassinolide (BL) are a class of polyhydroxy steroids phytohormones, that play a crucial role in several plant metabolic pathways and boost plants’ stress tolerance, but less data is accessible on its function in salt-affected grapevine. The experiment was conducted throughout the 2019 and 2020 experimental seasons at EL-Baramon experimental farm, Horticulture Research Institute, Mansoura, Egypt, to recognize the remediation potential of BL (1 and 2 mg L⁻¹) in lightening salinity (NaCl at 1000, 2000, and 3000 mg L⁻¹) injury on Thompson seedless grapevine seedlings (H4 strain) growth and physio-anatomical attributes. Data advocated that while salinity reduced growth attributes, BL applications substantially improved the overall salt-affected plant performance. Salinity stress significantly decreased photosynthetic pigment, relative water content, and ions percentage (nitrogen, phosphorus, potassium, potassium/sodium ratio). Alternatively, BL spraying significantly (p ≤ 0.05) increased the photosynthetic pigment, maintaining a favorable potassium/sodium ratio and increasing the ions percentage. Additionally, increasing salinity levels significantly boost plant sodium percentage and induce a membrane malfunction associated with increased membrane permeability; conversely, the application of BL decreased the sodium percentage associated with decreasing membrane permeability relative to non-treated salinized plants. Moreover, salinity and/or BL significantly improved the antioxidant capacity associated with rising proline accumulation and antioxidant enzyme activities. Anatomically, salinity stress considerably modified leaf structure; meanwhile, the spraying with BL drastically mitigates the harmful effects of salinity on leaf anatomy. Additionally, salt-affected plant cells explained various obvious organelles ultrastructural modifications and cellular damage; meanwhile, BL spraying to salt-affected plants repealed the ultrastructural modifications of cell organelles. Taken together, BL, especially 2 mg L⁻¹, has a great potential to boost the salt tolerance of Thompson seedless grapevine seedlings (H4 strain). It improves salt tolerance by sustaining higher photosynthetic pigment concentrations, maintaining ion homeostasis, regulating water status, and stimulating antioxidant capacity as well as maintaining leaf anatomical attributes.

THIS STUDY was achieved out during two successive seasons (2015 & 2016) The experiment was conducted on 16-year-old Thompson seedless grapevines. The vines were grown in a clay soil under surface irrigation system. Three material namely Chitosan, Salicylic acid and Fulvic acid applied at rate (500 ppm) were used as a spray application either single or in combination of them on the vine for three times, at growth start, one week after berry set and at veraison as an attempt to develop growth, berry quality and enhancement storage shelf life period of Thompson seedless grapevines. The Results appeared that single applications of Chitosan ,Salicylic acid and Fulvic acid or in combination of them were effective in improving shoot length, leaf surface area, total chlorophyll in the leaf and total protein in the canes in addition percentages of N, P and K in the leaves as well as enhancing yield per vine, cluster weight, berry weight, soluble solids content and total phenols while reducing total acidity, cluster weight loss% ,berry shatter % and berry decay% and total loss in cluster weight percentages during storage shelf life period. Also, enhanced berry adherence strength as compared with control in both seasons of study. Application of Chitosan + Salicylic acid + Fulvic acid was superior to using applications of Chitosan, Salicylic acid and Fulvic acid alone. In addition, the best results with regard to net profit of Thompson seedless grapevines were obtained when vines were sprayed with salicylic acid + fulvic acid.

This study was achieved out during two successive seasons (2018 & 2019) on 12 year-old Red Roumy grapevines. The chosen vines were grown in a clay soil under surface irrigation system in a private vineyard at El-deer hamlet, Aga, Dakahlia region, Egypt. Three amino acids namely tryptophan, proline and tyrosine were used as foliar application at rate 100 and 200 ppm on the vines for three times, at vegetative growth start, at full bloom stage and at verison stage. Results appeared that using tryptophan, proline and tyrosine were effective in improving shoot length, leaf area, total chlorophyll and total amino acids in the leaves in addition percentages of N, P, K and Mg in the leaves as well as enhanced yield per vine, cluster weight, berry weight, berry set, SSC content, total sugars, total anthocyanin and total phenols, also enhanced pruning wood weight, ripening wood, internode length and thickness while reduced titratable acidity in berries as compared with control in two seasons. Application of tryptophan at 200 ppm and tyrosine at 200 ppm gave the significant highest of vegetative growth parameters, yield and its components. While, proline at 200 ppm increased SSC% and SSC acid ratio, total anthocyanin, total phenols and total sugars while these reduced titratable acidity. The best net profit of Red Roumy grapevines was obtained with tryptophan at 200 ppm.

THIS study was carried out during two successive seasons (2016 and 2017) in a private vineyard orchard at Boktares village, Agacenter, Dakahlia Governorate, Egypt. The experiment was conducted on 5-years-old Crimson seedless grapevine cultivar. The vines were grown in a clay soil under surface irrigation system and cane trained using pergolla trellis system. The aim of work was study effects of jasmonic acid and girdling on yield andfruit quality of Crimson seedless grapevine. Jasmonic acid wasused as a foliar application at rate (10, 20, 40 ppm) at two times: after berry set and begging berry color (at veraison stage) alone or combination with girdling begging berry color at) veraison stage). The Results showed that applications of jasmonic acid + girdling were effective for improving yield per vine, cluster weight, berry weight, volume, berry length and width, redberries & pink berries (as a visual assessment) soluble solids content, totalsugar, total anthocyanin in berry skin and total phenols while decreased total acidity and greenberry. Moreover, enhanced pruning wood weight, ripening wood and total carbohydrates in canes as compared with the controlduring both seasons. In addition increment internode length, internode thickness and trunk thickness.The promising results in this respect were obtained when the vines were sprayed with jasmonic acid 40 ppm+ girdling.

The fruit quality of grapevines is a great importance for local consumption and export. Shoots and clusters thinning are substantial agricultural practices in grapevines to improve the berries quality. Herein, 10-years-old King Ruby grapevines were examined in two successive seasons. Four different levels of shoots number were applied (48, 42, 36, and 30, shoots/vine) with two different levels of clusters (30 and 24 clusters per vine). Results showed that the gradual decrease of shoots and clusters/vine improved vegetative growth parameters (shoot length and leaf surface area), total chlorophyll content, and microclimatic characteristics (light intensity, air temperature, and relative humidity); however, decreased yield/vine was observed. Consequently, enhanced chemical properties of berries (SSC, SSC/acid ratio total sugars, total anthocyanins, and total phenols) were obtained. In addition, an improved coefficient of wood ripening and total carbohydrates in canes was recorded. Moreover, the progressive increase in the number of shoots/vines in parallel with the decreased number of clusters/vine raised the cluster weight, cluster length, width, berry weight, length, and width. The thinning application of 30 shoots + 24 clusters per vine collectively achieved the significant highest values of vegetative growth, microclimatic parameters and berries quality, therefore, it could be recommended for application in King ruby vineyards under the Egyptian climatic.