سمیت تماسی نانوفرمولاسیون اسانس زیره سیاه (Bunium persicum) روی شته ‌مومی کلم، Brevicoryne brassicae (L.)

Biopesticides based on essential oils are considered a complementary or alternative method for chemical insecticides in integrated pest management programs. Controlled release by nano-encapsulated formulation has some advantages, to exemplify using more effectively over a time interval, improving the way of application, and reducing environmental damage. In the current study, the essential oil of Bunium persicum (Boiss.) B.Fedtsch. (Apiales: Apiaceae) was obtained by hydrodistillation and analyzed using gas chromatography (GC) and GC/mass spectrometry (MS). In situ polymerization technique was used to prepare nanocapsules of urea-formaldehyde loaded with essential oil extracted from B. persicum. Transmission electron microscopy (TEM) was performed to determine the morphology of the nanocapsules. Also, the diameter and poly-dispersity index (PDI) of nanocapsules were determined through the dynamic light scattering (DLS) technique. Subsequently, the contact toxicity of B. persicum essential oil and oil-loaded nanocapsules was assessed against the adult stage of Brevicoryne brassicae (L.) (Hemiptera: Aphididae). The adult aphids were exposed to different concentrations of the mentioned compounds at the standard environmental conditions (25±1℃, 65±5% RH, and a photoperiod of 16:8 h L:D). The chemical composition of B. persicum essential oil was measured and totally 28 components were identified. The main components of the essential oil were γ-Terpinen (36.62%), ρ-Cymene (18.41%), Carvacrol (13.60%), and Cuminaldehyde (13.50%). Characterization of nanocapsules using dynamic light scattering (DLS) and transmission electron microscopy (TEM) showed that the nanocapsules were nearly spherical with sizes between 8.11 to 14.62 nm, the median diameter (x50) of 10.88 nm, and a polydispersity index of 0.057. Based on the relative toxicity ratios, there were significant differences between non-formulated and B. persicum oil-loaded nanocapsules. After 96 h, the LC50 and LC90 values of contact toxicity of nanocapsulated formulation (365.43 and 1908.46 ppm, respectively) were significantly smaller than non-formulated essential oil (1030.40 and 3977.08 ppm, respectively). The results showed that nanoformulation of B. persicum essential oil could be considered as an efficient candidate in control of B. brassicae. Moreover, further studies are recommended to investigate the efficiency of the compound under field conditions.