2. Materials and methods
2.1. Insects
All insects used in our experiments were taken from a
T. granarium stock culture reared on pesticide-free wheat
grains in 3-l glass jars covered with mesh. Cultures were
kept in continuous darkness at a temperature of 3174 1C
and at 30–50% r.h. Insects used in experiments were kept
in an incubator in continuous darkness at a temperature of
3171 1C.
For different age larvae and pupae, eggs were allowed to
hatch and newly hatched larvae were designated ‘‘1-day
old’’. Larvae were tested at ages of 1–9 days, 10–18 days,
and 19–27 days. Newly-formed pupae were designated the
age ‘‘0’’ h and pupae were tested at 0, 24 and 48 h.