A simple protocol for somatic embryogenesis in Rosa hybrida L. cv. Apollo

Abstract

SummaryA successful regeneration system from in vitro-derived leaves of Rosa hybrida cv. Apollo, via somatic embryogenesis, has been established. The influence of different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and zeatin on the induction of embryogenic calli was evaluated. The highest percentage of embryogenic callus induction (48.3%) was obtained on full-strength MS medium containing 1.0 mg l–1 2,4-D, while at higher concentrations (4.0 or 5.0 mg l–1 2,4-D) no embryogenic calli were observed. The induction of embryogenic calli also occurred on MS media containing 0.5, 1.0, 2.0, or 4.0 mg l–1 naphthaleneacetic acid (NAA). The lowest concentration of NAA (0.5 mg l–1) showed the highest rate of production of embryogenic calli. For maturation, embryogenic calli were transferred onto MS media containing different concentrations of 6-benzyladenine (BA), thidiazuron (TDZ), or abscisic acid (ABA) alone, or in various combinations. The highest rate of embryo maturation (85.0%) was observed on MS medium supplemented with 1.0 mg l–1 ABA alone. Mature embryos showed the highest rate of germination on full-strength MS medium containing 2.0 mg l–1 BA alone. After rooting, well-developed plantlets were maintained under greenhouse conditions. The morphological characteristics and flower colours of somatic embryo-derived plants were the same as the donor parent.