In vivo polyploidy induction by colchicine in grape cultivar Ekşi Kara' (Vitis vinifera L.)
Polyploidization has been demonstrated as a very effective approach in grape improvement. It is known that grapes with increased ploidy level by mutation breeding have better qualities compared to their original diploids in some properties such as berry size, leaf size, and resistance to pests and diseases. For this purpose, studies on the folding of chromosome numbers have been made by applying chemical mutagen to diploid grape cultivars. In this study, colchicine was applied in vivo in order to raise the level of ploidy to Vitis vinifera L. 'Ekşi Kara' autochthonous grape cultivar seedlings. Seven colchicine dosages (g L‑1) (0.0, 1, 2, 3, 4, 5, 7, 10) were applied to meristematic part of seedling twice a day (in 8.30 and 18:00) during 3 days when first true leaves emerge. The effects of colchicine treatments have been investigated with changes in shoot and stoma size. Ploidy levels of the samples were tested using flow cytometry (FC). Blind seedling formation was determined in all of the 10 g L‑1 colchicine applications. In low-dose colchicine applications, shoot growth continued at various rates. Stomata sizes (density, length, width, and area) were recorded. The stoma properties were significantly affected the applications. FC analysis showed that the treated plants were not different from the original diploids of ploidy levels. It is known that as the level of ploidy increases in plants, the size of stoma increases and the density decreases. In this study, it was determined that the size of the stoma increases and the density of stoma decreases in the colchicine applied seedlings. Some colchicine applications are thought to alter the ploidy level. Chromosome analysis is required for precise detection. 10 g L‑1 colchicine applications cause blind seedling formation entirely. It has been understood that doses lower than 10 g L‑1 are more successful in promoting ploidy in 'Ekşi Kara' grape cultivar seedlings.
Kara, Z. and Yazar, K. (2020). In vivo polyploidy induction by colchicine in grape cultivar Ekşi Kara' (Vitis vinifera L.). Acta Hortic. 1276, 139-146
Vitis vinifera L., table grape, mutation, flow cytometry, improvement