Cryopreservation of shoot-tips of Aloe fievetii , an endangered species from madagascar, by droplet-vitrification

BACKGROUND: Aloe fievetii is endemic to Madagascar and is assessed as endangered by the IUCN Red List. Cryobiotechnology tools, such as micropropagation and cryopreservation, are valuable tools for propagating and preserving essential plants, including rare and endangered species. OBJECTIVE: This work aimed at developing a droplet-vitrification procedure designed explicitly for shoot tips from Aloe fievetii , that will allow the conservation of type plants. MATERIALS AND METHODS: Shoot tips from 6-week-old tissue-cultured plants were excised and subjected to a droplet-vitrification method. Two cryopreservation trials, in conjunction with the PVS2 treatment duration test, assessed the effectiveness of sucrose preculture and of pretreatment of shoot tips and donor shoots, respectively. RESULTS: After rewarming, optimal results were achieved after 30 min of exposure to PVS2. The highest recovery of plants (83%) was observed 12 weeks after rewarming of shoot-tips dissected from sucrose-treated plants. CONCLUSIONS: The treatment of donor plants with sucrose-enriched medium enhanced the regeneration of cryopreserved explants. This method represents the first reported protocol for cryopreserving shoot tips from an Aloe species .