Repellent and Attractant Effect of the Nettle Plant Urtica dioica on the Larvae of the Greater Wax Moth Galleria mellonella L. (Lepidoptera: Pyralidae)

The results of the study on the repellent and attractant effect of the nettle plant Urtica dioica on the larvae of the greater wax moth Galleria mellonella showed a variation in the average percentage of repellency and attraction of the insect larvae. The results of the statistical analysis confirmed that all treatments had a repellent effect on the third and fifth generation larvae of the greater wax moth, but at different rates. The percentage increased gradually with increasing concentration. The alcoholic extract was distinguished by giving the highest percentage of repellency and the lowest percentage of attraction, and the balance values were negative, which confirms that the alcoholic extract was repellent for the third generation larvae with an average of (86.67, 13.33, and -73.33%), respectively, and for the fifth generation larvae with an average of (96.67, 3.33, and -93.34%), respectively. The results of the study also showed that the aqueous extract of the nettle plant also had a good repellent effect on the third and fifth generation larvae and did not differ significantly from the alcoholic extract in the average percentages of repellency and attraction and the balance values, which were negative. The average for the third generation larvae was (80.00, 20.00, and -60%), respectively, and for the fifth generation larvae it was (93.33, 6.67, and -86.66%), respectively. On the other hand, the dry powder of the nettle plant gave lower percentages of repellency and attraction and balance values than the alcoholic and aqueous extracts, but the results were satisfactory. The dry powder was repellent for the third and fifth generation larvae with an average of (76.67 and 80.00%), respectively.