The cytokinin 6-Benzylaminopurine improves the formation and development of Dryadella zebrina (Orchidaceae) in vitro shoots

Plant micropropagation comprises biotechnological tools used for the conservation and mass propagation of orchid species. However, there are few reports of its use for orchids of the subtribe Pleurothallidinae. The present study evaluated the effects of 6-benzylaminopurine (BAP) on shoots formation and development of Dryadella zebrina (Porsch) Luer. For this, seeds were in vitro germinated, and the plantlets were submitted to different concentrations of BAP (0, 3, 6, 9, 12, and 15 µM). The plantlets derived from the treatments 0, 6, and 15 µM of BAP were collected after 60 days in culture and subjected to light microscopy analysis. Our results indicated that BAP increased the formation of the new shoots of D. zebrina , especially in treatment with 6 µM, and its use is indicated for the in vitro multiplication phase. The anatomical analyses of the roots showed a deleterious effect of 15 µM BAP on the meristematic region, with the presence of more vacuolated cells in this zone. Our results represent the first successful report of in vitro propagation for the genus Dryadella and may serve as a basis for further studies of in vitro propagation of phylogenetically related species.