In Vitro Regeneration and Somaclonal Variation of Catharanthus roseus Don. Using Leaf and Internodal Explants

This work was done at the Tissue Culture Laboratory of the Floriculture Department, Faculty of Agriculture, Alexandria University, Egypt, during the period from 2010 to 2012, to determine the effect of cultivar (Rosea and Alba), explant (leaf and internode) and different concentrations of two growth regulators (PGR) (IAA and  BA) on plant regeneration of Catharanthus roseus. The collected data were: callus induction, number of formed shoots, root induction and survival. Calluses developed from both leaf and intermodal explants of both cultivars when cultured on MS with PGRs. All the measured data were significantly influenced by the differences in cultivar, medium constituents and kind of explant. These differences were appeared in the interaction among them. Rosea was always superior to Alba. Internodal explant was better than leaf explant in all tested data. The medium which gave the highest average of callus induction was MS supplemented with 1.0 mg/l IAA+4.0 mg/l BA, while the medium without growth regulators did not produce any callus. The internodal explant of Rosea produced the highest mean value of shoot formation by MS medium supplemented with 0.0 mg/l IAA+4.0 mg/l BA. In vitro cuttings of regenerated Catharanthus roseus rooted easily. The highest rooting rate was recorded by MS supplemeted with 1.0 mg/l IAA+4.0 mg/l BA. 70% of the acclimatized plants survived and bloomed. Somaclonal variations were reported, show leaf variegation in color and morphology of some leaves. In this study different types of variants were obtained in leaf shape (28.5%).