Effects of biopesticide Neem EC on the Mamestra brassicae L. (Lepidoptera, Noctuidae)
Estonian University of Life Sciences, Institute of Agricultural and EnvironmentalSciences, Kreutzwaldi Str. 64, 51014 Tartu, Estonia; e-mail: Luule.Metspalu@emu.ee
Third instars larvae of the cabbage moth, Mamestra brassicae L. were exposed to Neem EC (M/S RYM Exports, The Indian Neem Tree Company) by a leaf-dip experiment (concentration of azadirachtin – 100 ppm). The after-treatment parameters studied the duration of the larval stage, mortality, and weight of pupae. Neem EC has shown significant prolongation in the development of larvae of M. brassicae: 18.5 days in the test variant, versus 14.8 days in the control. Neem EC also caused lethal failure of larval-larval and larval-pupal ecdysis, which is typical for insecticides possessing morphogenetic activity commonly referred to as IGR-activity. The mortality of larvae, prepupae and pupae in the test variant was significantly higher than in the control. The experiment in laboratory revealed that Neem EC inhibited larval development, greatly increased mortality, had antifeedant/deterrent effects and acted as a growth regulator for M brassicae larvae and pupae.