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Abstract In Egypt, grape (Vitis vinifera L.) occupies the second rank fruit acreage and production after citrus, but some of grape cultivars are ungrafted plants and these are highly sensitive to fungal diseases, nematodes, active lime 20% and insects, in specific phylloxera which cause high losses of both grape‟s yield and quality. Abiotic and biotic stresses could stand as an obstacle in face of conventional propagation of grapevine cultivation in vivo using hard- or soft- wood cuttings, layering, budding, or grafting between cultivars and rootstocks. Traditional grafting is the best alternative to overcome this constraint. Generally, for several grafting methods, nursery operators in many nurseries, using traditional grafting methods for grapevine, face a large difficulty for obtaining a high rate of successful grafts, therefore, failure rate of grafting is higher than desired, thus failure of grafting means loss of one year for the production of grafted seedling because it is season dependent. Also, the succeeded grafted seedling has to be incubated in a nursery about 1–2 year(s) to be ready for planting, so traditional grafting methods of grapevine is considered to be an expensive , needs highly skilled labour to achieve it and a time- consuming production method. In order to overcome some of these obstacles, different techniques, have been developed such as, micrografting process, through plant tissue culture technology, safely, rapidly in shorter time, and for large scale production. It decreases effort and costs as well as increase the percentage of successful micrografting transplants. So producing micrografted transplants by plant tissue culture techniques for grapes is considered to be a successful alternative avenue compared with traditional methods and a superior technology for the benefit of each of technicians, researchers, and commercial tissue culture laboratories, Nevertheless, the survival percentage of micrografting outcomes is limited.The practical aspect of this study was carried out in the Tissue Culture Laboratory of the Plant Production Department, the Faculty of Agriculture (Saba Bacha), Alexandria University in cooperation with the Tissue Culture Lab, Pharmaceutical Bio products Research Department. City of Scientific Research and Technological Applications in Burg El Arab during the period of 2016 till 2019. Three highly consumed important and well recognized grapevine (Vitis vinifera L.) cultivars viz „Superior Seedless, Flame Seedless and Crimson Seedless‟ were selected as examples for this species as scion explant donors. Those grapevine cultivars were, as one of the most widely grown in Egypt, whose commercial crops are traded both at the local and export levels. Also, three grape rootstocks as „Freedom, Paulsen 1103 and Salt Creek (Ramsey)’ were selected as rootstocks for micrografting procedures, they are considered of the most widespread and widely known rootstocks for grafting in vivo with its strong hairy roots and its ability to tolerate many pathogenic, soil pathogens such as fungal diseases or nematode as well as its ability to overcome the various physiological problems caused by soil chemical components such as calcium carbonate in the Calcareous soil. Therefore, the main goal of this study was undertaken by using in vitro grafting (micrografting) to cross-over the above mentioned obstacle. |