Developing a Hazomalania voyronii Essential Oil Nanoemulsion for the Eco-Friendly Management of Tribolium confusum, Tribolium castaneum and Tenebrio molitor Larvae and Adults on Stored Wheat

Abstract

Most insecticides commonly used in storage facilities are synthetic, an issue that generates concerns about food safety and public health. Therefore, the development of eco-friendly pest management tools is urgently needed. In the present study, a 6% (w/w) Hazomalania voyronii essential oil-based nanoemulsion (HvNE) was developed and evaluated for managing Tribolium confusum, T. castaneum, and Tenebrio molitor, as an eco-friendly wheat protectant. Larval and adult mortality was evaluated after 4, 8, and 16 h, and 1, 2, 3, 4, 5, 6, and 7 days, testing two HvNE concentrations (500 ppm and 1000 ppm). T. confusum and T. castaneum adults and T. molitor larvae were tolerant to both concentrations of the HvNE, reaching 13.0%, 18.7%, and 10.3% mortality, respectively, at 1000 ppm after 7 days of exposure. However, testing HvNE at 1000 ppm, the mortality of T. confusum and T. castaneum larvae and T. molitor adults 7 days post-exposure reached 92.1%, 97.4%, and 100.0%, respectively. Overall, the HvNE can be considered as an effective adulticide or larvicide, depending on the target species. Our results highlight the potential of H. voyronii essential oil for developing green nanoinsecticides to be used in real-world conditions against key stored-product pests.

Synthetic and Natural Insecticides: Gas, Liquid, Gel and Solid Formulations for Stored-Product and Food-Industry Pest Control

“…Recently, Kavallieratos et al [ 224 ] tested an essential botanical oil-based nanoemulsion (HvNE) (isolated from Hazomalania voyronii (Jum.) (Hernandiaceae)) applied as a wheat grain protectant against three storage Coleoptera species.…”

Essential Oil Coating: Mediterranean Culinary Plants as Grain Protectants against Larvae and Adults of Tribolium castaneum and Trogoderma granarium

“…The founding individuals of T. castaneum and T. granarium have been collected from Greek storage facilities since 2003 and 2014, respectively. The selected insect individuals of both species and developmental stages, as well as the conditions they were cultured in, were adapted from previous studies [40,59].…”

“…Essential oils have been studied in relation to their fumigant toxicity [30][31][32] and their contact toxicity [33][34][35], but only recently has there been a focus on novel application methods of EOs [36,37]. This research interest became fruitful by providing a solid methodological approach for the application of volatile compounds as stored grain coatings in the form of nanoemulsions (NE) [38][39][40][41]. Microemulsions (ME), on the other hand, are kinetically stable, oily droplets in water, with a Surfactant-to-Oil Ratio (SOR) usually higher than 2 [42].…”

Origanum vulgare Essential Oil against Tenebrio molitor (Coleoptera: Tenebrionidae): Composition, Insecticidal Activity, and Behavioral Response

“…Figure 1. Gas chromatogram profiles of peak retention of components of oregano essential oil: α-thujene (1), α-pinene (2), camphene (3), β-pinene (4), β-myrcene (5), α-phellandrene (6), α-terpinene (7), p-cymene (8), eucalyptol (9), γ-terpinene (10), cis-sabinene hydrate (11), terpinolene (12), linalool (13), camphor (14), borneol (15), terpinen-4-ol ( 16), α-terpineol (17), thymol methyl ether (18), carvacrol methyl ether (19), cuminaldehyde (20), thymol (21), carvacrol (22), aromandrene (23), β-bisabolene (24), and caryophyllene oxide (25).…”

“…The biological activity on insects caused by EOs varies according to plant species, and their efficacy has been demonstrated in coleopteran stored product pests [12,15,23]. Previous studies showed that Cymbopogon citratus essential oil is lethal to Ulomoides dermestoides Fairmaire (Tenebrionidae) [16], Hazomalania voyronii essential oil to Tribolium confusum (du Val) (Tenebrionidae) [24], and Zingiber pupureum essential oil to Lasioderma serricone Fabricius (Anobiidae) [25], favoring an effective approach toward Integrated Resistance Management (IRM). In this context, EOs from Amarydillaceae [26], Annonaceae [20], Lauraceae [27], Meliaceae [28], and Poaceae [29] are the most promising for causing toxic effects in insects.…”