Cryopreservation of banana (Musa spp.) meristem cultures after preculture on sucrose

Abstract A simple cryopreservation method is described for the long term-conservation of banana meristem cultures. It involves preculturing the proliferating meristems for 2–4 weeks on Murashige and Skoog medium, enriched with 0.3–0.5 M sucrose. Surviving meristematic clumps are then excised and transferred to cryotubes and plunged directly into liquid nitrogen for storage. The protocol was initially optimised for meristem cultures of the cultivar Bluggoe ( Musa spp., ABB group) and gave a viability rate of up to 42.5%. A reduction of the moisture content by exposure of the meristematic clumps to the sterile air flow of a laminar air flow bench did not result in an increased survival rate. This cryopreservation method was tested on seven banana cultivars belonging to different genomic groups and resulted in viability rates between 12 and 72% depending on the cultivar. Microscopical observations revealed that only the most meristematic parts of the proliferating clumps survived freezing.