Phytotoxic metabolites produced by Diaportheeres involved in cane blight of grapevine in Italy

Abstract

Grapevine trunk diseases (GTDs) are one of the most serious biotic stresses affecting this important crop. Among them a range of diseases were identified and associated to a plethora of phytopathogenic fungi, including species of Diaporthe. Diaporthe eres was recently identified as one of the species involved in cane blight of grapevine. The ability of a strain of this fungus isolated from infected grapevine plant in Italy to produce in vitro phytotoxic metabolites was investigated. Five phytotoxic metabolites were identified by their physical and spectroscopic properties as 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid, nectriapyrone, p-cresol and tyrosol. When tested on grapevine leaf disks and by leaf absorption, 4-hydroxybenzoic acid induced symptoms on both disks and leaves, 4-hydroxybenzaldehyde and p-cresol showed, respectively, phytotoxicity on leaf disks and on the leaf absorption bioassay.

Graphical Abstract

Keywords:

• Grapevine cane bleach
• Diaporthe eres
• fungal phytotoxins
• 4-hydroxybenzaldehyde
• 4-hydroxybenzoic acid
• p-cresol

Disclosure statement

The authors declare that there are no conflict of interest.

Acknowledgements

This manuscript was supported in part by academic grants from the Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Italy. Antonio Evidente is associated with “Istituto di Chimica Biomolecolare del CNR”, Pozzuoli, Italy.