title: Effect of Entomopathogenic Nematode Concentration on Survival during Cryopreservation in Liquid Nitrogen.
abstract: Entomopathogenic nematodes are used for biological control of insect pests. A method for improved cryopreservation of infective juvenile stage nematodes has been developed using Steinernema carpocapsae and Heterorhabditis bacteriophora. Optimum survival for both species was achieved with 12,000 infective juveniles/ml in glycerol and 7,500/ml in Ringer's solution. For S. carpocapsae, maximum survival also was observed with 60,000 infective juveniles/ml in glycerol and 25,000/ml in Ringer's solution. These concentrations resulted in 100% post-cryopreservation survival of S. carpocapsae and 100% retention of original virulence to Galleria mellonella larvae. This is the first report of achieving 100% survival of an entomopathogenic nematode after preservation in liquid nitrogen. Maximum survival of H. bacteriophora following cryopreservation was 87%.
authors.forename: Cheng
authors.initials: C
authors.lastname: Bai
authors.forename: David I
authors.initials: DI
authors.lastname: Shapiro-Ilan
authors.forename: Randy
authors.initials: R
authors.lastname: Gaugler
authors.forename: Shuxia
authors.initials: S
authors.lastname: Yi