Heterorhabditis bacteriophora is a cruiser strategist that exhibits long distance ranging searches for insect hosts in soil. We characterised age-based variations in constituent behaviours and total lipid reserves of laboratory-aged H. bacteriophora infective juveniles. Individuals demonstrated extensive behavioural variability within the first 7 days, followed by accentuated ranging behaviour during the next 14 days and, finally, a decline in activity during the last 15 days. Frequency, bout duration and total time investment decreased almost 50% for forward crawling but almost doubled for backward crawling and curling. Both pausing and head waving frequency, a theoretical correlate of searching intensity, varied considerably without relation to age. Lipid content declined steadily, decreasing by 56% after 28 days. Behavioural changes became apparent after a 20% reduction in total lipid, and performance continued to decline with further lipid depletion. These findings emphasise the combined influences of environmental and physiological factors on behavioural plasticity in entomopathogenic nematodes.
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Agronomy and Crop Science
- Entomopathogenic nematode