Influence of Auxin (2.4-D,NAA and TDZ) on callus induction from different explants of Hibiscus sabdariffa

The production of Hibiscus sabdariffa (Roselle) in Sudan has increased during the last few years mainly by increasing the area under production. The crop is sold in both domestic and foreign markets. It is also important as a natural coloring material for drugs and many other products. In addition, it is used as traditional medicine while oil from its seed is used as a lubricant is for lighting, making soap, paints, and varnishes. Seeds are also used for animal feeding. The crop is still produced by traditional methods under rainfed conditions and is thus affected by the uncertainty and fluctuation of rainfall. The high cost involved in implementing modern production techniques discourages adoption of improved practices. Due to these conditions, Roselle yields in Sudan are far below the potential of the crop. In this study we investigated the ability of different explants of Roselle and hormone type and concentration to induce callus to develop an efficient and reproducible regeneration protocol. Results showed that callus can be induced from Hibiscus sabdariffa. The best Clorox concentration for seed sterilization was 40%, the best Murashige & Skoog’s medium (MS) concentrations suitable for seeds germination is full MS medium. The highest weight of callus obtained was from cotyledon explants grown in full MS media supplemented with 4mg/l of naphthalene acetic acid (NAA) hormone. Key words: Hibiscus sabdariffa, regeneration protocol, roselle, Sudan, tissue culture technique