Abstract

The Chilean rhizomatous geophyte Alstroemeria pelegrina (A. pelegrina), a species endemic to the Coquimbo (31°45′ S) and Valparaíso (33°12′ S) regions, is currently classified as vulnerable and experiencing population decline due to loss of habitat. This heightened threat underscores the need to develop effective mass propagation techniques to support its conservation efforts. Consequently, the present study aimed to establish an optimized in vitro propagation protocol tailored specifically for A. pelegrina to facilitate its large-scale propagation and promote the preservation of this vulnerable geophyte. In our experiment, explants obtained from in vitro germination were used. These explants were then cultured on a Murashige and Skoog (MS) medium solidified with agar (6 g L−1) and supplemented with 2.22 μM 6-Benzylaminopurine (BAP) and 30 g L−1 sucrose. The results indicated an average of 4.6 new shoots produced per initial explant. The implementation of light-emitting diode (LED) illumination with a red:blue ratio of 3:1 and 2.22 μM BAP resulted in an average shoot length of 6.2 cm. For rhizome induction, the addition of either 5.37 μM 1-naphthaleneacetic acid (NAA) or 5.37 μM indole-3-butyric acid (IBA) resulted in average rhizome lengths of 1.9 cm and 1.7 cm, respectively, with fresh weights of the vitroplants ranging from 2.9 g to 3.1 g, and rooting percentages between 100% and 96%, respectively. Notably, the survival rate of rooted plants obtained through in vitro propagation was 90% after a 4-week acclimatization period in a cold greenhouse, indicating the efficacy of the developed protocol for mass propagation and conservation efforts of this vulnerable geophyte species.