Biological effect of sweet wormwood, Artemisia annua methanol extracts and essential oil against Helicoverpa armigera Hub. (Lepidoptera: Noctuidae)
Neelima Anshul, Alok Kalra and Dwijendra Singh
Methanolic extract of different parts of Artemisia annua, (Leaf, shoot, and seed) and essential oil were evaluated for their effect on growth and development of larvae of Helicoverpa armigera. The experiments were done by the incorporation of different extracts and essential oil in semi- synthetic diet at two percent concentration. Among leaf, stem, seed extract and essential oil treatments the larval weight was reduced by diet containing essential oil (69.71%) and leaf extract of A. annua (60.21%) as compared to control. The prolongation of larval and pupal period and an average more than fifty percent IGR activity was recorded by the treatments of A. annua extract and essential oil. The growth retardation, including reduced weight and prolongation of larvae may possibly interrupt the production of insect hormone- ecdysone level in insect body which also delayed the pupation. Physiological effects found in treated larvae included formation of larva pupa intermediate and adultoids.