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

<i>Tenebrio molitor</i> is one of the main stored product pests. This study characterized oregano essential oil (OEO) by gas chromatography (GC/FID and GC/MS) and assessed its insecticidal properties against <i>T. molitor</i>. Mortality, survival, respiration, and behavioral...

Full description

Saved in:
Bibliographic Details
Main Authors: Angelica Plata-Rueda, José Cola Zanuncio, José Eduardo Serrão, Luis Carlos Martínez
Format: article
Language:EN
Published: MDPI AG 2021
Subjects:
Online Access:https://doaj.org/article/b0d9923e31d443a88fc74eac438acc12
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:<i>Tenebrio molitor</i> is one of the main stored product pests. This study characterized oregano essential oil (OEO) by gas chromatography (GC/FID and GC/MS) and assessed its insecticidal properties against <i>T. molitor</i>. Mortality, survival, respiration, and behavioral response in larva, pupa, and adult of this insect were determined. The major components of OEO were carvacrol (25.6%), p-cymene (12.3%), linalool (8.71%), thymol (7.22%), γ-terpinene (7.21%), caryophyllene oxide (4.67%), α-pinene (2.71%), and eucalyptol (2.69%). OEO caused high contact toxicity in larvae (LD<sub>50</sub> = 3.03 µg insect<sup>–1</sup>), pupae (LD<sub>50</sub> = 5.01 µg insect<sup>–1</sup>), and adults (LD<sub>50</sub> = 5.12 µg insect<sup>−1</sup>) of <i>T. molitor</i>. Survival rates were 100% in larvae, pupae, and adults of <i>T. molitor</i> not treated with OEO, declining to 65–54%, 38–44%, 30–23%, and 6–2% in insects treated with LD<sub>25</sub>, LD<sub>50</sub>, LD<sub>75</sub>, and LD<sub>90</sub>, respectively. Low respiration rates of <i>T. molitor</i> at different developmental stages was observed after OEO exposure. Additionally, OEO exposure affects behavioral avoidance response and causes repellency in larvae and adults. These findings show that OEO exerts insecticidal and repellent effects against <i>T. molitor</i>, suggesting a potent alternative to synthetic insecticides for controlling the beetle.