In vitro short-term storage of Stanhopea tigrina Bateman ex Lind.

Stanhopea tigrina is a plant endemic to Mexico, listed as threatened in national and international standards because of the fragmentation of its habitat and the overexploitation of its natural populations. Therefore, programs for the conservation and propagation of this genetic resource should be implemented. This study aimed to establish an efficient protocol for the in vitro conservation of S. tigrina. To this end, three plant growth inhibitors were evaluated: abscisic acid (ABA), paclobutrazol (PBZ), and ancymidol (ACD), at concentrations of 0, 0.5, 1.0, and 2.0 mg L−1. In addition, an osmoregulator, polyethylene glycol (PEG), at 0, 10, 20, and 30 g L−1, was evaluated. Subsequently, the conserved material was regenerated using 2 mg L−1 of 6-benzylaminopurine (BAP). After 180 days of in vitro conservation, growth and development variables (survival rate, number of shoots and roots, shoot length) were evaluated. For in vitro conservation 2 mg L−1 ABA generated, the lowest shoot height (1.6 cm), the lowest number of shoots (4.3), and the lowest number of roots (3.7). In contrast, with the control treatment, in which shoots of 7.2 cm height, 4.5 shoots per explant, and 6.95 roots were obtained. Regeneration of 3.2 shoots per explant was achieved with 2 mg L−1 BAP, in addition to root growth during the multiplication phase. During the acclimatization process, 80% plant survival was observed. That according to the results obtained, this study contributes to conservation studies on this species, which is currently threatened with extinction.