Cryopreservation of in vitro-grown shoot tips of the medicinal species Cleome spinosa (Cleomaceae) applying vitrification-based techniques

BACKGROUND: Few cryopreservation studies have been reported with the genus Cleome. Due to the use of C. spinosa in traditional medicine and its valuable pharmacological potential, the long-term conservation of the species will allow the safe maintenance of its germplasm. OBJECTIVE: This study compares two vitrification-based techniques on the cryopreservation of shoot tips of C. spinosa. MATERIALS AND METHODS: The effect of sucrose preculture and different vitrification solutions was evaluated using vitrification and V Cryo-plate techniques. The supplementation of recovery medium with BAP was also assessed. RESULTS: The V Cryo-plate proved to be the most efficient technique. Treatment of shoot tips with PVS2 at 0 degrees C resulted in a higher regeneration response after cryopreservation when compared to treatment with PVS2 and PVS3 at 25 degrees C. The highest survival (83.3%) and recovery (76.6%) were achieved for shoot tips exposed to PVS2 for 90 min at 0 degrees C and recovered on MS medium supplemented with 0.5 mg L-1 BAP for 2 weeks. CONCLUSION: Plants regenerated from cryopreserved shoot tips maintained their in vitro multiplication capacity and showed a normal phenotypic aspect, demonstrating the efficiency of the cryopreservation protocol