Wax moth (Galleria mellonella) is serious pests of beeswax worldwide. These study was conducted to
estimate the effectiveness of three plant oils (Lemongrass oil, Moringa oil and Pumpkin oil), argon gas and
conjunction of them to develop alternative method of controlling the 4th larval instar of G. mellonella. Potential
activities of active ingredients on mortality percentage and duration of exposure to wax moth at four concentrations
(3, 1.50, 0.75and0.37%v/w) were estimated. Data cleared that the mortality effect depends on applied material type
and concentration. Lemongrass oil was recorded (100%) larval mortality 7 days post-treatment, being of highest
activity comparing with the two other materials and control. Results showed that after 3 days post-treatments by
Lemongrass oil, the LC50 value was 2.18 % (v/w). The LT50 values against the 4th larval instar of G. mellonella
were 22.48, 45.09 and 68.04 hr. for Argon 100, 80 and 60%, respectively. In general, the larval mortality was
higher in binary treatments (plant oils (LC50) mixed with Aragon gas) than individual treatments only by the oil. It
was the best treatment Lemongrass oil (LC50 2.18) +Ar.(100) where the full mortality (100.0%) of larvae was
achieved 24 hours after treatment, treatment with this combination Lemongrass oil (LC50 2.18)+Ar.(100)increased
AchE and decreased Cytochrome P-450, GST, α- amylase and invertase when compared to the control. However,
these results clarified the necessity to more research in order to affirm their effect in the field