Content area
Full text
Abstract
A new delivery system was used to control the black cutworm Agrotis ipsilon (Hub.) (Lepi., Noctuidae) based on incorporation of geranium essential oil into solid lipid nanoparticles (SLNs) in a controlled-release formulation using ultrasonic solvent emulsification technique. The morphology of geranium oil nanoparticles after loading (GO-SLNs) was characterized and visualized using transmission electron microscopy (TEM). The abundance and percentage content of major components did not show any significant difference between free and nano-encapsulated oil when analyzed by (GC-MS). The results of geranium essential oil bulk form were compared with that of oil post loading solid nanoparticles and tested in the laboratory and field for their efficiency on larval development, pupal mortality and adult longevity. Laboratory bioassay indicated that (GO-SLNs) was more effective on both larval and pupal development as well as the adult longevity and female fecundity accordingly the percentage of hatchability. Field-laboratory experiments were conducted to show direct and residual effects of the tested oil free and post loading using two concentrations (5.0 and 2.5%), in terms of speed of mortality, toxicity and stability. (GO-SLNs) was more stable under field conditions and gave a high percentage of mortality at the two concentrations used.
Keywords: Geranium oil, nanoparticles, Agrotis ipsilon, pest management
INTRODUCTION
The black cutworm A. ipsilon is one of the most destructive insects attacking different field crops, such as cotton, clover, corn, soybean, potatoes and tomatoes not only in Egypt but also in several countries throughout the year. Great losses occurred in yield due to A. ipsilon infestation special at seedling stage (Atwa et al. 2016). Control of this pest relies heavily on the use of many chemical insecticides; these chemicals caused different problems such as ozone depletion, resistant behavior and environmental pollution, toxicity to non-target organisms (Desneux et al. 2007).
Biopesticides based on essential oils appear to be a complementary or replace synthetic insecticides method in crop production and integrated pest management. and the deleterious effects of the natural products extracted from different plants of different families acted as ovicidal and larvicidal against different pests can be manifested in several manners including mortality, antifeedant, growth inhibitor, suppression of reproduction behavior accordingly fecundity and fertility (Isman 2006, Sharaby and El-Nujiban 2015). On the other hand the secondary metabolites (allelochemicals) from these...