# Insecticidal Activity of Angelica archangelica Essential Oil and Transcriptomic Analysis of Sitophilus zeamais in Response to Oil Fumigation

## TL;DR

Angelica archangelica essential oil shows strong insecticidal effects against the maize weevil, impacting survival and gene expression, offering a potential eco-friendly pest control solution.

## Contribution

The study identifies the insecticidal activity and transcriptomic response of S. zeamais to Angelica archangelica essential oil, supporting plant-based pesticide development.

## Key findings

- AAEO significantly reduced S. zeamais survival with LC50 values decreasing over time.
- AAEO inhibited detoxification enzyme activities in S. zeamais.
- RNA-seq identified 3718 differentially expressed genes in response to AAEO fumigation.

## Abstract

The maize weevil, Sitophilus zeamais, is a globally distributed stored-grain pest that causes significant losses to cereals, posing a serious threat to food security. We investigated chemical composition and fumigation activity of Angelica archangelica root essential oil (AAEO) against S. zeamais. The main components of AAEO and its median lethal concentration (LC50) for fumigation against this pest were identified. The enzymatic activities of acetylcholinesterase, glutathione-S-transferase, and carboxylesterase were measured when fumigated by AAEO LC50. The study demonstrates that AAEO exhibits strong insecticidal activity against S. zeamais, affecting survival, detoxification enzymes, and gene transcription. The present study provide a scientific basis for the development of effective plant essential oil-based insecticide against S. zeamais.

Sitophilus zeamais is one of the most destructive pests of stored grains. Both adults and larvae penetrate and consume the grains, thereby diminishing the grain quality and nutritional value. We determined the chemical composition of Angelica archangelica essential oil, its fumigation toxicity against S. zeamais, and its effects on the activities of detoxification enzymes in the insects. RNA-seq was performed to analyze the impact of the essential oil on the transcriptional level of S. zeamais, and qRT-PCR was conducted to validate the differentially expressed genes. Chemical analysis identified 35 components in essential oil, including δ-3-Carene (24.26%), Limonene (19.81%), and α-Pinene (14.96%). A significant positive correlation was observed between the fumigation activity of the essential oil and the applied dose. The median lethal concentrations (LC50) values were 164.38, 132.62, and 90.35 mg/L air at 24, 48, and 72 h, respectively. Fumigation significantly inhibited the activities of the three detoxification enzymes. RNA-seq revealed a total of 3718 significantly differentially expressed genes (DEGs). qRT-PCR confirmed that the expression patterns of the DEGs were consistent with the RNA-seq data. This study comprehensively evaluates the control efficacy of A. archangelica essential oil against S. zeamais and provides data support for developing novel, eco-friendly, plant-based pesticides.