Obtaining grape plants start material by the in vitro method

The objective of the study is to identify the optimal parameters for obtaining healthy grape planting material of the "Initial" category in vitro culture to develop an improved technology for creating basic mother plants. The experimental study was carried out at the breeding and biotechnology laboratory of the Federal State Budgetary Scientific Institution NC FSC HVW, (Krasnodar). The research years were 2021–2024. The following grape rootstocks were taken as objects for study: Berlandieri × Riparia Kober 5BB, Berlandie-ri × Riparia SO4, Berlandieri × Rupestris Ruggeri 140, Riparia × Rupestris 101-14; nutrient media containing mineral salts according to the Murashige and Skoog (MS) prescription, in concentrations of 1/2 MS, 1/3 MS, and 1/4 MS. The generally accepted research methods in the practice of clonal micropropagation of plants were used: sterilization of the source material, introduction into in vitro culture, clonal micropropagation itself, rooting in vitro with subsequent adaptation to in vivo conditions. During the micropropagation of the Berlandieri × Riparia Kober 5BB grape rootstock, a 1/2 MS medium supplemented with 6-BAP (0.5 mg/L) and IAA (0.5 mg/L) was suitable for the rooting or pre-rooting stage. This medium produced the longest shoots, with an average shoot length of 4.37 cm, 3.25 leaves, and a leaf surface area of 3.88 cm2. A medium with a reduced macrosalt content is often used for rooting plants, and in our case, roots also formed well on this medium. The average number of roots was 4.15, with a length of 8.57 cm. The other treatments produced slow-growing shoots with shortened internodes. A nutrient medium consisting of 1/2 MS + 0.5 mg/L IAA + 0.5 mg/L 6-BAP can be used during the propagation of Kober 5 BB, SO4, Ruggeri 140, and 101-14 rootstocks by cuttings, as well as during the elongation and rooting stages.