ABSTRACT
An applicable in vitro callus initiation and shoot regeneration of commercial sugar beet breeding lines was investigated. Procedures are described for producing different types of callus and competent callus formation able to produce shoots. Leaf, cotyledon and hypocotyl explants taken from in vitro grown seedlings were subjected to Murashige and Skoog (MS) medium containing different combination of plant growth regulators. The leaf explants of genotype 436 showed the highest competent callus production able to form shoot when 0.1 mg L-1 α-Naphthaleneacetic (NAA) acid was used in combination with 1 mg L-1 thidiazuron (TDZ). Hypocotyl explants of IC genotype showed the highest callus formation when 0.1 mg L-1 NAA was combined with 0.3 mg L-1 6-Benzylaminopurine (BAP). Cotyledon explants of IC genotype showed the high callus production when 0.3 mg L-1 TDZ was combined with 0.1 mg L-1 NAA. The result evaluation demonstrated that cotyledon explants of genotype 436 produced more callus than IC genotype which able to produce shoot and the best callus induction medium was MS medium in combination with 0.1 mg L-1 NAA and 1 mg L-1 TDZ. In conclusion, TDZ was more effective cytokinin than BAP and NAA was more efficient auxin than both Indol-3-Acetic Acid (IAA) and 2, 4-Dichlorophenoxyacetic acid (2, 4-D).