Effects of shoot tip colchicine applications on some grape cultivars

Polyploidization can provide changes in vital features such as growth, development, environmental stress tolerance in plants. Colchicine is one of the most commonly used chemicals as a polyploidization agent. In this study, 2-year-old ‘Ekşi Kara’, ‘Gök Üzüm’ and ‘Trakya İlkeren’ (2x, Vitis vinifera L.) saplings grown on their own roots were used. When the enforced shoots reached about 15 cm length, colchicine applied (0, 2.5 g L-1, 5 g L-1, 7.5 g L-1) 24 and 48 hours to the lateral shoot tips. The effects of treatments were evaluated by shoot tip viability, stoma size and density, chloroplast counts, and flow cytometry (FC) analysis, and ‘Kyoho’ (4x) used as control. The maximum stomatal variations were determined in Ekşi Kara cultivar at 2.5 g L-1 24-h application. Based on morphological differences, FC analysis was performed only in ‘Ekşi Kara’ but, there was no genomic duplication. Since the morphological differences were not sufficient in the diagnosis of polyploid in grape cultivars, FC analysis should be performed to achieve confirmed results.