Dry-freezing infective juveniles for robust preservation of stocks.

Cryopreservation allows strains to be stored, eliminating genetic drift and maintenance costs. Existing cryopreservation methods for the economically-important entomopathogenic nematode involve multiple incubation and filtration steps to precondition the animals. The standard protocol for freezing the model organism in buffer is simpler, and a recent dry-freezing protocol allows stocks to survive multiple freeze-thaws, a possibility during a power failure. Here we report the efficacy of cryopreservation protocols adapted for . We show that dry freezing with disaccharides, but not glycerol-based or trehalose-DMSO-based freezing buffer, allows reliable recovery of infective juveniles.