Development of the entomopathogenic nematode Heterorhabditis bacteriophora strain HP88 was studied in vivo with larvae of the greater wax moth, Galleria mellonella, as host and in vitro. At 25 C in vivo, the duration of the life cycle from egg hatch to egg hatch was 96 hours. Juvenile development took 48 hours, with the duration of each juvenile stage ranging from 8 to 12 hours. Under crowded conditions, development proceeded to the infective juvenile (IJ) stage instead of the third juvenile stage (J3). Life-cycle duration and proportion of the various developmental stages in the population were similar in in vitro and in vivo cultures. When in vivo or in vitro development was initiated from the IJ stage, only hermaphrodites developed in the first generation and males appeared only in the second generation. The average (+/-SD) number of progeny per hermaphrodite was 243 +/- 98. The ratio of males to hermaphrodites in the second generation was 1:9.4 +/- 6.8.
Keywords: Heterorhabditis bacteriophora; development; life cycle; nematode; reproduction; sex ratio.