Effects of culture methods and plant growth regulators on in vitro propagation of Brassavola nodosa (L.) Lindl. hybrid

Abstract

Brassavola nodosa (L.) Lindl. is an epiphytic orchid with great potential for the ornamental plant industry. The lack of information on propagation and production techniques limits the development of large-scale commercial production. Furthermore, this species is experiencing a reduction in population due to habitat destruction, the impact of climate change, and over-collection from native habitats. This study aimed at developing an efficient protocol for micropropagation of B. nodosa, which could be valuable towards the large-scale commercial production as well as for conservation of this species. Six different concentrations of plant growth regulators (BA or IBA, with or without adenine sulfate) were evaluated in modified Murashige and Skoog (MS) medium for shoot multiplication. In addition, two concentrations of either NAA or IBA were evaluated for rooting. Explants were cultured under three different culture media conditions: semi-solid medium, liquid medium (partial immersion), and liquid medium (complete immersion). Results indicate that B. nodosa could be successfully micropropagated in liquid culture with partial immersion. The modified MS medium supplemented with 2.0 mg L−1 BA and 30.0 mg L−1 adenine sulfate resulted in higher multiplication rates. Rooting was obtained using either 0.5 mg L−1 NAA or 1.0 mg L−1 IBA with no significant differences between both rooting treatments. Plantlets achieved 100% ex vitro survival after 30-d acclimatization.