We carried out micropropagation and initiated somatic embryogenesis in grapevine (Vitis vinifera L.). For micropropagation, nodal segments of four grapevine varieties; 'Refošk', 'Laški rizling', 'Zeleni sauvignon' in 'Malvazija' were inoculated on four different media. Each culture medium was inoculated with 15 nodal explants of the varieties 'Refošk' and 'Zeleni sauvignon', 10 nodal explants of the variety 'Laški rizling', and four nodal explants of the variety 'Malvazija'. Media M1 and M2 were based on Murashige and Skoog medium supplemented with vitamins, whereas M3 and M4 were based on McCown Woody Plant medium. Media M1 and M3 were additionally enriched with the cytokinin BAP (2 mg/L). Nodal segments on M1 and M3 developed more numerous but shorter shoots with fewer internodes and a compact appearance, while those on M2 and M4 produced fewer shoots, which were longer and had more nodes. The highest number of new nodes was recorded for the cultivar ‘Zeleni sauvignon’ on M1 medium. After 58 days, the resulting nodal segments were subcultured on hormone-free medium to evaluate their potential for further propagation. Subculturing was successful for plants originating from M2 and M4, while most plants from M1 and M3 declined. For somatic embryogenesis, leaf explants and petioles were inoculated to observe callus formation. We used Nitsch and Nitsch basal medium supplemented with hormones 2,4-D (2 mg/L) and BAP (2 mg/L in SE1 and 1 mg/L in SE2). Leaf explants exhibited better callus induction than petioles, and more callus was produced on SE2 medium. Based on the results, we recommend the use of the cultivar 'Zeleni sauvignon' in future studies, as it showed the best response in micropropagation. The best results were obtained on medium M3 (2 mg/L BAP), where nodal explants produced the highest number of shoots, while for the initial steps of somatic embryogenesis, medium SE2 with 1 mg/L BAP proved to be the most effective, also in the cultivar 'Zeleni sauvignon'.
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