Effects of different nutrient media on the gynogenesis induction in onion (Allium cepa L.) breeding materials

In this thesis, gynogenic responses of five onion genotypes (three breeding lines produced at Pamukkale University, one open pollinated domestic line and one open pollinated variety) collected from different regions of Turkey were observed. In this thesis, five onion genotypes with superior quality features collected from different regions of turkey were observed for their gynogenic responses. 29010 surface sterilized unopened flower buds of onion genotypes were cultured in BDS and MS based six different medium containing different sucrose concentration (30 g/l and 100 g/l) and plant growth regulators (2 mg/l BAP and 2 mg/l 2,4-D). Approximately half of the buds were subcultured after 21 days. The subculture medium contains 30 g/l of sugar, without plant growth regulators. Approximately two months after bud cultivation and subculture, gynogenic responses started to be observed. It was observed that the gynogenic plants obtained from the subcultured buds developed healthier and stronger. When the response rates of different onion genotypes to ginogenesis were compared, it was showed that DELFOS (0.98%) genotype was the highest and obtained from subculturing MBDS-1 medium to MBDS-2 medium. 76 of the obtained gynogenic plants were analyzed by flow cytometry. In total, 48 (63.10%) of them were haploid; 18 (23.70%) of them were diploid, and 10 (13.10%) of them were mixoploid. Key words: Allium, Gynogenesis, Tissue culture, Haploid