# Chemical Composition and Antifungal Activity of Artemisia sieversiana Essential Oil Growing in Jilin Against Black Spot on Yanbian Pingguoli Pear in China

## TL;DR

This study investigates the chemical composition and antifungal properties of Artemisia sieversiana essential oil against black spot disease in Pingguoli pears.

## Contribution

The study identifies the chemical constituents of Artemisia sieversiana essential oil and demonstrates its antifungal efficacy against black spot pathogens.

## Key findings

- Artemisia sieversiana essential oil contains 42 compounds, with 1,8-cineole and trans-caryophyllene as major constituents.
- The essential oil exhibited antifungal activity with MIC and MFC values of 0.10% and 0.12% (v/v), respectively.
- SEM analysis showed morphological damage to fungal mycelia after treatment with the essential oil.

## Abstract

Black spot disease substantially impairs both the aesthetic quality and commercial viability of affected Pingguoli pears. Previous studies have shown that Alternaria alternata and A. tenuissima are the pathogens that cause black spot disease. Essential oils represent novel alternatives to synthetic fungicides to control these pathogens. This study extracted Artemisia sieversiana essential oil (AsEO) by hydro-distillation using a crystal tower pure dew essential oil machine. The chemical compositions of AsEO were analyzed via gas chromatography–mass spectrometry (GC–MS). A total of 42 compounds were detected. 1,8-cineole, trans-caryophyllene, (1R,4S)-1,7,7-trimethylbicyclo [2.2.1] heptan-2-yl acetate, (±)-camphor, and β-myrcene were identified as the five main constituents. Moreover, the antifungal activity of AsEO was assessed against black spot on Yanbian Pingguoli pear in China. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values were determined as 0.10% (v/v) and 0.12% (v/v), respectively. Scanning electron microscopy (SEM) analysis revealed that treatment with AsEO induced significant morphological aberrations in A. alternata and A. tenuissima mycelia, including surface roughening, hyphal collapse, and loss of structural integrity. Concurrently, a marked increase in alkaline phosphatase (AKP) enzyme activity and electrical conductivity was observed, a key indicator of cell wall and plasma membrane permeabilization and damage. When the concentration of AsEO was less than 120 µg/mL, there was no toxicity to keratinocytes (HaCaTs) and skin fibroblasts (NHSFs). In summary, this study provides a theoretical basis for the development of AsEO as a fungicide against black spot disease on Pingguoli pear in China.