Efficacy of essential oils of thymbra capitata l. and mentha pulegium l. collected in tunisia on larvae of Galleria mellonella L.

Abstract

The wax moth is one of the honeybee pests that cause a lot of damage and loss for the beekeepers in Tunisia. The use of insecticides is more and more used although they are known to contaminate wax and honey. This study aims to test the essential oils of two North African common plants Thymbra capitata L. and Mentha pulegium L. efficacy as alternative method by fumigation on instars of Galleria mellonela L. We also determined the duration of the development stages of the great wax moth (GWM) presented in Tunisia. Results showed that under a temperature ranged between 30 and 33°C, the total duration from eggs to adults of GWM lasted 51 days. The fumigant test showed the toxicity of both oils on larvae instars tested. The second larvae instar was more susceptible than the 4th instar. Moreover, M. pulegium was more toxic against the 2nd larvae instar than T. capitata with an LC50 at 48h of 41.82 and 456.27 µl/L air, respectively. The essential oils present a good alternative to the insecticides to control wax moths.

The wax moth is one of the honeybee pests that cause a lot of damage and loss for the beekeepers in Tunisia. The use of insecticides is more and more used although they are known to contaminate wax and honey. This study aims to test the essential oils of two North African common plants Thymbra capitata L. and Mentha pulegium L. efficacy as alternative method by fumigation on instars of Galleria mellonela L. We also determined the duration of the development stages of the great wax moth (GWM) presented in Tunisia. Results showed that under a temperature ranged between 30 and 33°C, the total duration from eggs to adults of GWM lasted 51 days. The fumigant test showed the toxicity of both oils on larvae instars tested. The second larvae instar was more susceptible than the 4th instar. Moreover, M. pulegium was more toxic against the 2nd larvae instar than T. capitata with an LC50 at 48h of 41.82 and 456.27 µl/L air, respectively. The essential oils present a good alternative to the insecticides to control wax moths.