Toxicity of Some Essential Oils Constituents against Oriental Fruit Fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)

Abstract

The massive use of synthetic pesticides to manage agricultural pests results in environmental pollution and health hazards. The secondary plant metabolites, which are majorly dominated by terpenoids, have the potential to be developed into novel alternatives to synthetic chemicals. Therefore, in our current investigation, six majorly dominated essential oil constituents were evaluated for their toxicity against adults and immature stages of oriental fruit flies, Bactrocera dorsalis, a worldwide fruit pest. The results indicated that carvacrol was the most toxic essential oil constituent (EOC) to adult flies, with LC50 of 19.48 mg/mL via fumigant assay, followed by thujone 75% mortality via ingestion toxicity test against adult fruit flies. Similarly, when larvae were dipped in different concentrations of EOCs, carvacrol appeared as the most toxic EOC with the lowest LC50 (29.12 mg/mL), followed by (−)-alpha-pinene (26.54 mg/mL) and (R)-(+)-limonene (29.12 mg/mL). In the oviposition deterrence tests, no egg was observed on oranges seedlings treated with 5% of each EOC (100% repellency). Regarding the repellency assay, a significantly higher number of flies (77%) were repelled from the Y-tube olfactometer arm containing (−)-alpha-pinene, followed by carvacrol (76%). Our results showed that the selected essential oil constituent has the potential to be developed as an alternative to synthetic pesticides against B. dorsalis. However, further research is required to assess the activities of these EOCs under open-field conditions.

Olfactory receptors in Bactrocera species for sustainable fruit fly management: A review and future perspectives

“…Plant volatiles as an alternative to synthetic chemicals in pest management has been emphasized in several studies (Figure 3) (Ameye et al, 2018, 2015; Isman, 2020; Jaffar & Lu, 2022). For example, studies have shown that the plant volatiles, such as methyl salicylate, linalool, carvacrol, limonene and β‐caryophyllene, can enhance the effectiveness of IPM programs.…”

“…In addition, numerous studies have investigated the role of plant volatiles in reducing pest population damage to crops. For instance, 2‐undecanone, limonene, α‐pinene, β‐pinene and trans‐β‐farnesene have shown potential in repelling pests from fruit and crops (Cui et al, 2012; Jaffar & Lu, 2022; Ntalli et al, 2016; Zapata & Smagghe, 2010). Furthermore, plant volatiles have been demonstrated to be highly effective in monitoring and detecting pest populations (Conboy et al, 2020).…”

“…Several studies have demonstrated the potential of plant essential oils in controlling Bactrocera species (Ali, 2018; Jaffar & Lu, 2022). For example, essential oils and their constituents of Citrus sinensis , Eucalyptus obliqua and Mentha arvensis can significantly reduce the fly populations.…”

D-Limonene: Promising and Sustainable Natural Bioactive Compound

“…Interestingly, D-limonene was present in salivary gland extracts of Ceratitis capitata [145] and D-limonene had an attractive effect on H. irritans irritans at concentrations below 0.1%, indicating that D-limonene has potential application in trapping these insects [144]. In addition, D-limonene not only inhibited the fecundity activity of Bactrocera dorsalis but also showed a significant toxic effect on adults and pupae and exhibited a dose-dependent killing effect on larvae [146]. However, Papanastasiou et al [147] found that D-limonene exhibited acute toxicity to the insect at high concentrations but promoted its survival and reproduction at low concentrations, probably due to the hormetic-like effect of D-limonene.…”

Non-consumptive effects mediated by fire ant footprints mitigate fruit damage by Bactrocera dorsalis (Hendel)

“…These ndings highlight the potential of non-consumptive pest control strategies in reducing pest populations and impacting population dynamics.Several repellent chemicals have been assessed for their effectiveness against B. dorsalis, such as botanicals from Seriphidium brevifolium, Piper nigrum, Azadirachta indica, and quercetin, as well as various oils. These compounds have shown promising results in repelling B. dorsalis and reducing crop damage(Liu et al 2019;Jaleel et al 2020;Jaffar et al 2022). However, their e cacy in natural environments remains uncertain.…”