Gerbera jamesonii is one of the most popular cut flowers in the world and micropropagation is the commercial way for its propagation. This method allows for obtaining large amounts of healthy homogenous plants. Thus, it is necessary to establish efficient micropropagation protocols. The objective of this study was to evaluate the organogenic response of G. jamesonii, orange and pink cultivars, under in vitro culture. Different levels of Gamborg s medium (BA) (2, 4 and 6 mg/l) and thidiazuron (TDZ) (0.2, 0.4 and 0.6 mg/l) in combination with indole-3-acetic acid (IAA) (0 and 0.1 mg/l) in MS medium were evaluated for shoot induction. For proliferation, regenerated shoots in TDZ were subcultured in medium supplemented with 0.2, 0.4 and 0.6 mg/l TDZ, 2 mg/l BA or 2 mg/l Kin and regenerated shoots were subcultured onto BA in induction medium. In the second phase, media of MS, 1/2 MS, MS with 1/2 NH4NO3 and KNO3 concentration (MS-1/2N), MS with 1/2 micro and iron elements (MS- 1/2MI), B5 and 1/2 B5 on shoot induction and proliferation, were evaluated. In order to induce shoot rooting, different levels of IAA (1, 2 and 3 mg/l) and 1-Naphthaleneacetic acid (NAA) (1, 2 and 3 mg/l) in combination with sucrose (30 and 40 g/l) were evaluated. Maximum shoot induction (88.8 and 44.4% for orange and pink cultivars, respectively) and multiplication rate per transplant (7.6 shoots/explant for orange cultivar and 1.33 shoots/explant for pink cultivar) were obtained in media with 4 mg/l BA and 0.1 mg/l IAA. The most efficient media for shoot induction and proliferation were MS-1/2N and MS, respectively. The best rate of shoot rooting in orange (4.6 roots/explants with 4.83 cm length) and pink cultivars (5.13 roots/explants with 6.2 cm length) was obtained in media with 3 mg/l IAA and 30 mg/l sucrose. The establishment of plantlets was done successfully with 92% of survival in the glasshouse.

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