Micropropagation of Rosa damascena Mill. through transverse thin cell layer culture

Abstract

A basic factor underlying the success of large‐scale micropropagation and genetic transformation of any plant species is regeneration. In order to regenerate propagules of Rosa damascena Mill. on a large scale, an efficient and improved in vitro propagation system has been established using transverse thin cell layer culture (tTCL). By optimizing the position of the tissue and applying an improved selection procedure, in vitro shoots were elongated in 8 weeks of culture. Modified Murashige and Skoog (1962)(MS) medium fortified with 4.0 mg l‐1 6‐benzylaminopurine (BAP) and 0.4mg l‐1 anaphthalene acetic acid (NAA) gave optimal shoot regeneration. The explant was inoculated on this medium in the upright position and exhibited a high frequency of shoot regeneration (~96.66%), and it also gave the highest number of shoots (22.33/explant). The horizontally placed explant on an average 7.66 shoots/explant. Our experiments indicate that explant orientation strongly influences the organogenesis response. The frequency of shoot initiation and the number of multiple shoots produced from each explant were significantly dependent on the plant source, concentration of plant growth regulators and the orientation of the explants and contributed significantly to in vitro regeneration. Rooting of well developed shoots was achieved on hormone free ¼ strength MS medium with 4% sucrose.