Repellent activity of nanoencapsulated essential oil of Artemisia sieberi Besser on Plutella xylostella L. larvae

Recent research has focused on insecticidal property of essential oil plants in biological control of insects. Controlled release by nanoencapsulated essential oil seems to be the best choice for increasing the efficiency and minimization of environmental damage. In this work, efficiency of nanoencapsulated essential oil of Artemisia sieberi Besser was tested on repellent activity of Plutella xylostella L.. Several concentrations were prepared and then third instars larvae were introduced into each treatment. Then, repellent activity was determined after 1, 3, 6, 12 and 24 h from commencement of exposure. Results showed that at 1.9 ppm the nanocapule of Artemisia oil was shown here to possess more repellent activity (80%) to P. xylustella compered to Artemisia oil (62%) before formulation after 24h. The repellent activity varied with application method and concentrations and exposure time. The results showed higher repellent rates in nanocapsule than in essential oil due to controlled-release formulations allowing smaller quantities of essential oil to be used more effectively over a given time interval. The reasons for nanocapsulating the essential oil have been to improve its stability to reduce side effects or to reduce dosing frequency and total dosing amount, to obtain better repellent activity, and for sustained (long-lasting) release. Therefore the nanocapsulation of A. sibeiri might provide a new method for the management of P. xylostella.