Effects of explants types and plant growth regulators on in vitro propagation of Kalanchoe beharensis

Abstract

Donkey’s ears (Kalanchoe beharensis Drake), a succulent plant in the Crassulaceae family, is commonly grown as an ornamental species. Traditional propagation methods using seeds and stem cuttings are insufficient to meet market demand. In this study, optimal in vitro propagation methods for K. beharensis were investigated. The objectives were to examine the effects of explant types and plant growth regulators (PGRs) on explant regeneration. In the explant type experiment, leaves, distal leaf blade, basal leaf blade, shoot, and stem segments were cultured on Murashige and Skoog (MS) medium. Results showed that leaf explants produced the highest number of regenerated shoots with a 95% shoot regeneration rate, whereas shoot explants produced the highest number of regenerated roots with a 100% root regeneration rate. To evaluate the effects of PGRs, 6-benzylaminopurine (BAP) and thidiazuron (TDZ) were applied at concentrations of 0, 0.1, and 0.5 mg/L. BAP at 0.1 mg/L induced the highest number of shoots, whereas higher concentrations reduced shoot production. In shoot explants, no significant differences were observed between the BAP concentrations. TDZ was more effective for callus induction than for shoot regeneration. Overall, the results demonstrated an efficient method for the in vitro propagation of K. beharensis using plant tissue culture techniques. Furthermore, microscopic examination revealed distinctive xerophytic anatomical features and histological responses of leaf and shoot explants under different cytokinin treatments, representing the first anatomical characterization of this species and providing baseline data for future comparative and tissue culture studies.