Optimizing culture medium ingredients and micrografting devices can promote in vitro micrografting of cut roses on different rootstocks

Abstract

Tissue culture and micrografting techniques are known as effective procedures to produce healthy rose rootstocks and high quality scions. In order to establish successful micrografting protocol for roses, several factors including different concentrations of Benzylamino-purine (BA) (0, 1, 1.5, 2 mg l−1) + 0.1 mg l−1 α-Naphthaleneacetic acid (NAA), sucrose concentrations (30, 50, 70 g l−1), types of grafting devices (aluminium foil, parafilm, paper bridge), and types of rose scions cultivars (Rosa hybrida cv. Red One, R. hybrida cv. Samurai) on two different types of native (Rosa canina) and commercial rose rootstocks (Rosa multiflora cv. Natal Briar) were examined. The high micrografting success (100%) was micrografting R. hybrida cv. Samurai scion on R. mutiflora cv. Natal Briar rootstock with the paper bridge as the best grafting device in the liquid Van der salm (VS) medium containing 2 mg l−1 BA + 0.1 mg l−1 NAA + 300 mg l−1 Casein Hydrolyzate + 2 g l−1 myo-inositol + 50 g l−1 sucrose. Treating the wounded explants (scions and rootstocks) with silver nitrate (50 mg l−1) during the micrografting process, increased the survival of micrografts. The micrografted plants were successfully rooted and well acclimatized. The present results provide the first efficient protocol to produce high successful micrografted rose plantlets in tissue culture. It is the first research protocol for micrografting of native and commercial roses by considering important factors relating to successful micrografting such as plant growth regulators, growth adjuvants, grafting devices, and medium ingredients.