Influence of genotype, explant source, and gelling agent on in vitro shoot regeneration of chrysanthemum

The capacity for shoot regeneration of leaf, petiole, and stem explants of eleven chrysanthemum cultivars was examined on the MS medium containing 1 μM naphthaleneacetic acid and 10 μM 6-benzyladenine solidified with 0.8% Agar, 0.4% Agarose, or 0.25% Gelrite. Significant differences in frequency of callus formation and regeneration from the different explants were observed among the different cultivars when grown on the media solidified with the different gelling agents. Gelrite was found to be the most effective gelling agent in promoting of the shoot. Of the different explants used, in general, stem exhibited the highest frequencies of shoot organogenesis and mean number of shoots per explant regardless of cultivar and gelling agent. However, the highest frequency of regeneration (11.67 shoots per explant) was noted from leaf explants of cv. Borami followed by (4.33 shoots per explant) from stem explants of cv. Yes Nuri. Shoots were directly developed from the surface of explants, not through callus formation. Low frequencies of shoot organogenesis were observed for the remaining cultivars except for cvs. Yes Time and Yes Star, which exhibits no shoot formation at all. In this study, we have developed an efficient in vitro protocol for cvs. Borami and Yes Nuri from suitable explant.