EFFICACY OF HETERORHABDITIS-BACTERIOPHORA (STRAIN OLI) IN RELATION TOTEMPERATURE, CONCENTRATION AND ORIGIN OF THE INFECTIVE JUVENILE

The effects of temperature and inoculum density on the biocontrol effi cacy of Heterorhabditis bacteriophora were studied. Efficacy of infect ive juveniles from hermaphroditic females and amphimictic females were compared using Galleria mellonella as hosts. The infective juveniles were placed in contact with insects at concentrations of 2, 4, 8, 16 a nd 32 individuals per host. Temperatures varied between 12 degrees C a nd 36 degrees C at intervals of 2 degrees C. Temperature, concentratio n of infective juveniles and origin of juveniles had significant influ ences (p less than or equal to 0.01) on host mortality. Highest mortal ity was recorded at 26 degrees C. Infective juveniles of the hermaphro dites killed more G. mellonella than did those of the amphimictic fema les.