# Multivariate Statistical Analysis of Solidago canadensis L. Essential Oil and Its Antifungal Mechanism Against Mulberry Sclerotinia Diseases

## TL;DR

This study explores the antifungal potential of Solidago canadensis L. essential oils against a fungus that harms mulberry trees, offering a natural alternative to chemical pesticides.

## Contribution

The study introduces a green pesticide from Solidago canadensis L. essential oils and reveals its antifungal mechanism through multivariate and transcriptomic analyses.

## Key findings

- Flower-derived essential oils showed the highest antifungal efficacy against Ciboria shiraiana with an EC50 of 0.642 μL/mL.
- α-pinene and myrcene were strongly correlated with antifungal activity.
- SLEOs disrupt fungal cell membranes and induce oxidative stress, leading to cell damage.

## Abstract

Ciboria shiraiana (C. shiraiana), a pathogenic fungus, is a major threat to mulberry trees, causing mulberry sclerotinia diseases. Current control strategies primarily rely on chemical pesticides, whose long-term use leads to adverse effects such as pesticide residues, environmental pollution, and pathogen resistance. This study aimed to develop a green pesticide derived from the essential oil (EOs) of Solidago canadensis L. (S. canadensis L.) and to analyze its antifungal mechanism. SLEOs were extracted from flowers, leaves, and stems of S. canadensis L. via hydro-distillation. Their chemical composition was analyzed by GC-MS. Multivariate statistical analysis was used to assess compositional differences among SLEOs from various plant parts and evaluate the correlation between their chemical components and antifungal efficacy. The antifungal mechanism of SLEOs against C. shiraiana was investigated using an integrated approach combining transcriptomics with physiological and biochemical analyses. The EO yield varied with plant part: flowers yielded the most (1.00% ± 0.07%), followed by leaves (0.76% ± 0.04%) and stems (0.05% ± 0.01%). Flower EOs (FEOs) strongly inhibited C. shiraiana, with an EC50 value of 0.642 μL/mL. α-pinene and myrcene showed the highest correlation with antifungal activity. Transcriptomic and physiological data revealed that SLEOs compromise cell wall and membrane integrity, infiltrate cells, and trigger leakage of intracellular contents. Additionally, SLEOs inhibited activities of antioxidant enzymes (SOD, CAT, and POD), leading to intracellular ROS accumulation, oxidative stress, lipid peroxidation, and DNA damage. SLEOs constitute a promising natural and environmentally sustainable antifungal agent. Their activity is linked to specific components and a multi-target mechanism involving membrane disruption and oxidative stress induction. This study provides a foundation for developing plant-based agents to manage mulberry sclerotinia diseases.