Fumigant Toxicity of Lamiaceae Plant Essential Oils and Blends of Their Constituents against Adult Rice Weevil Sitophilus oryzae

Abstract

Abstract:To find a new and safe alternative to conventional insecticides, we evaluated the fumigant toxicity of eight Lamiaceae essential oils and their constituents against the adult rice weevil Sitophilus oryzae. Of the eight species tested, hyssop (Hyssopus offcinalis), majoram (Origanum majorana), and Thymus zygis essential oils showed strong fumigant toxicity against S. oryzae adults at 25 mg/L air concentration. Constituents of active essential oils were analyzed by gas chromatography coupled to flame ionization detector (FID) and gas chromatography-mass spectrometry. A total of 13, 15, and 17 compounds were identified from hyssop, majoram, and Thymus zygis essential oils, respectively. Pinocamphone and isopinocamphone were isolated by open column chromatography. Among the test compounds, pinocamphone and isopinocamphone showed the strongest fumigant toxicity against S. oryzae. Sabinene hydrate, linalool, α-terpineol, and terpinen-4-ol exhibited 100% fumigant toxicity against S. oryzae at 3.9 mg/L air concentration. The measured toxicity of the artificial blends of the constituents identified in hyssop, majoram, and Thymus zygis oils indicated that isopinocamphone, terpine-4-ol, and linalool were major contributors to the fumigant toxicity of the artificial blend, respectively.

Biocidal Potential and Chemical Composition of Industrial Essential Oils from Hyssopus officinalis, Lavandula × intermedia var. Super, and Santolina chamaecyparissus

“…littoralis ( EC 50 = 49 μg/cm 2 ), but inactive against the other pests ( Table ). The essential oil of this species has proven activity against Thrips palmi and Sitophilus oryzae , [ ][ ] and against adults and nymphs of the mite Tetranychus urticae …”

Chemical composition, insecticidal and biochemical effects of Melaleuca alternifolia essential oil on the Helicoverpa armigera

“…Essential oils from aromatic plants, and their major constituents, are considered to be an alternative to conventional pesticides for controlling many insect pests, due to several advantages over synthetic pesticides, including rapid degradation, low residual and not easily generated cross-resistance (Mc Donnell et al, 2016;Werdin González, Stefanazzi, Murray, Ferrero, & Fernández Band, 2015;Wollinger et al, 2016). Moreover, plant essential oils are high volatile and a rich source of bioactive chemicals (Kim, Lee, Jang, Jung, & Park, 2016). Acting on the nervous system of insects is one of the important modes of action of high volatility, which lead antifeedant and repellent effect to insects (Abdullah et al, 2015;El-Wakeil, 2013).…”

Biological activity of some essential oil constituents in four Nepeta L. species against Sitophilus oryzae L.

“…So S. oryzae is considered a major and cosmopolitan insect pest because of adults (male and female) and larvae are insatiable feeders and vary of grains mass. (Park et al 2003;Kim et al 2016).…”