Screening of Five Lamiaceae Essential Oils as Repellents for Sweet Potato Weevil, Cylas Formicarius (F.) (Coleoptera: Brentidae)

Abstract

In this research, the repellent activity of five Lamiaceae essential oils, Agastache rugosa, Elsholtzia blanda, Elsholtzia ciliata, Elsholtzia penduliflora, and Plectranthus ovatus, was evaluated against sweet potato weevil, Cylas formicarius using a two-choice test between the essential oil-treated filter paper and the control. E. blanda and A. rugosa essential oils have some sweet potato weevil attractant properties at low dose (<47.16 nl/cm2),while N,N-diethyl-3-methylbenzamide (DEET), P. ovatus, E. penduliflora, and E.ciliata essential oils have repellent properties at doses ranging from 15.72 nl/cm2 to 196.49 nl/cm2. The effect of type of essential oil and their dose were interactively associated with repellent efficacy. There was a increase in repellent efficacy as the dose increased for all essential oils. The repellent activities of P. ovatus essential oil and E. penduliflora were higher than the others, and the repellent effects of E. ciliata essential oil and DEET were more dose-dependent than others, indicating that at low dose, P. ovatus and E. penduliflora essential oils have stronger repellent efficacy, but at higher dose DEET and E. ciliata have greater effects. Our findings clearly demonstrate that P. ovatus, E. penduliflora, and E. ciliata essential oils are candidate materials for future investigation as repellent compounds against sweet potato weevil control.

Tailoring IPM plans to fight a cloaked pest: helping smallholder farmers combat the sweetpotato weevil in sub-Saharan Africa

“…Research on pest-controlling botanicals is still a field of interest. Examples of the botanicals which have shown some promise for SPW control are extracts from plant parts, and especially nuts, of the tropical tree Page 12 of 20 Keyser et al CABI Agriculture and Bioscience (2024) 5:28 Melia volkensii (Jaoko et al 2021), yam bean seed extract, karanj oil (Prasad et al 2022), neem oil (Leng and Reddy 2012;Prasad et al 2022), and essential oils from various plant sources (Mai et al 2021). Although many studies on the effects of essential oils are limited to laboratory experiments and have yet to demonstrate effectiveness in the field, this area is continuing to be explored.…”

Acute and Sub-Chronic Intraperitoneal Toxicity Studies of the Elsholtzia ciliata Herbal Extract in Balb/c Mice

“…Notably, moderate doses of Elsholtzia plants have not been linked to adverse effects in humans [30]. While a recent acute toxicity study [31] conducted on female white nonlinear mice yielded no observable behavioral changes, there is evidence suggesting toxic effects on food storage pests [20,21,32].…”