Effects of growth regulators on in vitro shoot regeneration and rooting of F1 hybrid (between Cymbidium aloifolium (L.) Sw. 1799 and Cymbidium finlaysonianum Lindl. 1833)

Abstract

This study evaluates the effects of plant growth regulators on in vitro shoot regeneration and root formation of the F1 hybrid between ♀ Cymbidium aloifolium and ♂ Cymbidium finlaysonianum. Experiments were conducted on MS medium supplemented with cytokinin group (Kinetin, TDZ, BAP) to assess shoot multiplication and auxin group (IBA, NAA, IAA) to evaluate root formation. The results showed that 2.0 mg/L BAP was the optimal concentration for shoot multiplication, producing 4.30 shoots per explant, a shoot length of 7.73 cm, and a fresh weight of 323.05 mg. During the rooting phase, the combination of 2.0 mg/L NAA and 2.0 g/L activated charcoal resulted in 5.20 roots per explant, a root length of 6.35 cm, and a fresh weight of 355.05 mg, surpassing other treatments. The findings provide a scientific basis for refining the in vitro propagation protocol of F1 hybrid orchids, contributing to the development of valuable new propagation materials for the conservation and commercialization of potential orchid varieties.