A Metabolomic and HPLC-MS/MS Analysis of the Foliar Phenolics, Flavonoids and Coumarins of the Fraxinus Species Resistant and Susceptible to Emerald Ash Borer.

Sohail S Qazi,Domenic A Lombardo,Mamdouh M Abou-Zaid

doi:10.3390/molecules23112734

Sohail S Qazi, Domenic A Lombardo + Show 1 more

Open Access

https://doi.org/10.3390/molecules23112734

Copy DOI

Abstract

The Emerald Ash Borer (EAB), Agrilus planipennis, Fairmaire, an Asian invasive alien buprestid has devastated tens of millions of ash trees (Fraxinus spp.) in North America. Foliar phytochemicals of the genus Fraxinus (Oleaceae): Fraxinus pennsylvanica (Green ash), F. americana (White ash), F. profunda (Bush) Bush. (Pumpkin ash), F. quadrangulata Michx. (Blue ash), F. nigra Marsh. (Black ash) and F. mandshurica (Manchurian ash) were investigated using HPLC-MS/MS and untargeted metabolomics. HPLC-MS/MS help identified 26 compounds, including phenolics, flavonoids and coumarins in varying amounts. Hydroxycoumarins, esculetin, esculin, fraxetin, fraxin, fraxidin and scopoletin were isolated from blue, black and Manchurian ashes. High-throughput metabolomics revealed 35 metabolites, including terpenes, secoiridoids and lignans. Metabolomic profiling indicated several upregulated putative compounds from Manchurian ash, especially fraxinol, ligstroside, oleuropin, matairesinol, pinoresinol glucoside, 8-hydroxypinoresinol-4-glucoside, verbenalin, hydroxytyrosol-1-O-glucoside, totarol and ar-artemisene. Further, dicyclomine, aphidicolin, parthenolide, famciclovir, ar-turmerone and myriocin were identified upregulated in blue ash. Principal component analysis demonstrated a clear separation between Manchurian and blue ashes from black, green, white and pumpkin ashes. The presence of defensive compounds upregulated in Manchurian ash, suggests their potential role in providing constitutive resistance to EAB, and reflects its co-evolutionary history with A. planipennis, where they appear to coexist in their native habitats.

Highlights

The Emerald Ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive wood-borer indigenous to Asia that has caused widespread mortality of North American ash (Fraxinus spp.) [1]
Because of the intricate nature of the foliar chemistry of the genus Fraxinus, the use of HPLC-MS/MS and autonomous untargeted metabolomics provided the necessary means for investigating the issue
The current study presents the first report on the High-throughput metabolomic analysis of the foliar chemistry of the six Fraxinus spp

Summary

Introduction

The Emerald Ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive wood-borer indigenous to Asia that has caused widespread mortality of North American ash (Fraxinus spp.) [1]. Since its accidental introduction in North America, that can be traced back to 1990 [2], EAB infestations have been identified in twenty-five American states and two Canadian provinces. In the majority of cases, ash trees are killed within six years of EAB infestation or detection [1]. The Genus Fraxinus (Oleaceae, Olive family) has sixty species, of which sixteen of them are native to North America, and amongst them four species are native to Canada [3]. In North America, the EAB is a major invasive pest threatening all of the North American species, including Fraxinus pennsylvanica var. In North America, the EAB is a major invasive pest threatening all of the North American species, including Fraxinus pennsylvanica var. subintegerrima (Vahl) Fern. (Green ash), F. americana L. (White ash), F. pennsylvanica Marsh

Objectives

Methods

Results

Conclusion