The obtention of tetraploid watermelon (Citrullus lanatus (Thunb.) matsum ve nakai) plants by in vivo and in vitro methods

This study was planned to produce tetraploid watermelon plant which is the main production material of seedless watermelon. In this study watermelon cultivar Crimson Sweet was used and the effects of 2 in vivo and 2 in vitro methods on the obtention of tetraploid plant were investigated. In the first in vivo method, 7 different colchine solutions (0.0 %, 0.1 %, 0.2 %, 0.3 %, 0.4 %, 0.5 % ve 0.6 %) were applied by droping to the apical growing point at the first true leaf stage in the other technique, the apical growing points of the greenhouse grown plants were immersed in to (0.0 %, 0.5 % and 1.0 %) colchine solution. In the first experiment of in vitro methods, the cotyledons were regenerated in MS medium containing 4 different concentrations (0, 1, 2, 4 mg/l) of BA were added. In the other technique, 3 different colchicine solution (0.0 %, 0.5 % and 1.0 %) were applied to the in vitro diploidmicrocuttings. According to the results, the most succesful method to obtain tetraploid plants of C. Sweet watermelon cultivar was the regeneration in MS medium containing 4 mg/l BA was added and the duplication rate was 60.4 %. The second successful method was the in vitro colchicine application (0.5 %) with rate of 36.4 % tetraploid plants. The duplication rate of in vivo methods was 5 % that was not found enough successful. The ploidy level of the plants which obtained by in vivo and in vitro methods was analysed with flow cytometry. Morphological and cytological observations were also done to determine tetraploid plants