In Vitro Callus Formation and Shoot Regeneration from Hypocotyl and Cotyledon Explants of Tomato (Lycopersicon esculentum Mill.)

In this study, the effects of various plant growth regulators and culture conditions on the callus induction and shoot regeneration in m-28 hybrid cultivar of tomato have been evaluated. the seeds were germinated in half strength (½) murashige-skoog (ms) medium and the cotyledon (5x5 mm) and hypocotyl (5 mm) segments of the 10 day old seedlings were cultured on semi-solide ms medium containing different concentrations and combinations of plant growth regulators. the best result on callus formation, both explants (cotyledon and hypocotyl) and both culture conditions (photoperiodic condition at 16 hours light-8 hours dark ve 25 days dark condition after photoperiodic condition), was found ms medium supplemented with 1 mg/l bap+1 mg/l naa (%100 callus formation). at the adventitious shoot induction, under dark condition after photoperiodic condition, the best results were obtained from ms medium supplemented with 2 mg/l kin+0.2 mg/l iaa, only 2 mg/l bap and only 3 mg/l tdz and both explants (regenerated explant from %72 to %100). the highest number of shoots regenerated per explant (17.30±5.72 number), was found under dark condition after photoperiodic condition at ms medium supplemented with tdz of cotyledon explants. the highest adventitious shoot length (33.00±0.57 mm) and the number of leaf in shoot (3.00±0.00 number) were obtained at ms supplemented with 1 mg/l bap+1 mg/l naa of hypocotyl explants and photoperiodic conditions.