In vitro callogenesis induction of Guarianthe skinneri (Bateman) Dressler and W.E. Higgins (Orchidaceae)

Abstract

Guarianthe skinneri (Bateman) Dressler and W.E. Higgins, is a native orchid from Mexico, considered as threatened species in the NOM-ECOL-059-SEMARNAT-2010, mainly due to the disappearance of its natural habitat and illegal collection during the flowering season. The aim of this research was to induce in vitro callogenesis using different types of explants and phytoregulators, in order to establish a mass production technique as a contribution to the conservation of this species. We evaluated leaf and pseudobulb pith explants growing in semi-solid medium MS, adding BAP, 2, 4-D, Kin, the combination of BAP/2 and 4-D/Kin/Sad and a control without any type of plant growth regulators. Statistical analysis showed that pseudobulb pith explants are more suitable for in vitro callus induction in comparison to leaf explants, because of a lower percentage of contamination (18.8% in pith and 73.2% in leaves). Likewise, the pseudobulb pith explants showed increased callus formation (10.8%) in comparison to leaf explants (7.6%). Regarding the phytoregulators employed, BAP promoted increased callus formation (17%) compared to other phytoregulators (7-10%). This is the first report of the use of pseudobulb pith as an explant for callus induction in G. skinneri.Guarianthe skinneri (Bateman) Dressler and W.E. Higgins., is a native orchid from Mexico, considered as threatened species by NOM-ECOL-059-SEMARNAT-2010, mainly due to the disappearance of its natural habitat and the illegal collection during its flowering season. The aim of this research was to induce in vitro callogenesis from different type of explants, using phytoregulators, in order to look for a massive production technique to contribute to its conservation. We evaluated the leaf and pseudobulb marrow explants growing in semi-solid medium MS adding BAP, 2, 4-D, Kin, the interaction of BAP/2, 4-D/Kin/Sad and a control without any type of plant growth regulators. Statistical analysis showed the pseudobulb marrow explants are more suitable for in vitro introduction in comparison to leaf explants, since they perform a lower percentage of contamination (18.8% in marrow and 73.2% in leaves). Likewise, the pseudobulb marrow explants increased callus formation (10.8%) in comparison to leaf explants (7.6%). Regarding the phytoregulators employed, BAP have allowed to increased callus formation (17%) compared to other phytoregulators (7-10%). This is the first report, which proposes the use of pseudobulb marrow as explant for callus induction in G. skinneri