Essential Oil Composition of Three Native Persian Plants and Their Inhibitory Effects in the Cabbage Looper, Trichoplusia Ni Publisher



Khanavi M^{1, 2} ; Laghaei P¹ ; Isman MB¹ Show Affiliations
Source: Journal of Asia-Pacific Entomology Published:2017

Abstract

Essential oils of Thymus kotschyanus, Pistacia atlantica and Bunium persicum were analyzed by GC–MS. Growth inhibitory and insecticidal effects of all oils were evaluated in the cabbage looper. Also, Bunium persicum essential oil and its major compounds were chosen for topical and fumigant applications. All essential oils were characterized by high levels of monoterpenoids with thymol and carvacrol as major constituents of T. kotschyanus, α-pinene as the main component of P. atlantica and ρ-cymene, limonene, γ-terpinene and cuminaldehyde as the main constituents of B. persicum essential oil. The oil of B. persicum and cuminaldehyle showed the most inhibition and toxicity on larval growth. In a contact toxicity assay, cuminaldehyde exhibited the highest activity (LD50 = 68.8 and LD95 = 196.2 μg larva− 1) and a notable additive interaction with other main compounds of the oil. ρ-Cymene was the most toxic component via fumigation (LD50 = 39.8 and LD95 = 96.2 μg/ml). Also, a binary solution of ρ-cymene and γ-terpinene was synergistic in terms of fumigation toxicity with a synergy ratio of 1.6. Our results indicate that B. persicum essential oil merits further consideration for use in pest management. Also, the additive and synergistic activity of major compounds provides an opportunity to formulate a promising green pesticide. © 2017