Phytotoxic metabolites by nine species of Botryosphaeriaceae involved in grapevine dieback in Australia and identification of those produced by Diplodia mutila, Diplodia seriata, Neofusicoccum australe and Neofusicoccum luteum

Abstract

Botryosphaeria dieback is one of the main trunk diseases of grapevine caused by several species of Botryosphaeriaceae. Twenty-four fungal isolates representing the eight most widespread and most virulent Botryosphaeriaceae were tested for their ability to produce phytotoxic metabolites. The chromatographic profiles of their culture filtrates organic extracts showed the ability of all isolates to produce several and different metabolites. When tested on grapevine leaves and tomato cuttings the organic extracts phytotoxicity varied among isolates and species. To our knowledge, this is the first study on phytotoxic compounds produced by Botryosphaeriaceae species found in Australian vineyards. The phytotoxic metabolites produced by Diplodia seriata, Diplodia mutila, Neofusicoccum australe and, for the first time, by Neofusicoccum luteum were isolated and chemically identified essentially by spectroscopic methods.

Keywords:

• Grapevine Botryosphaeria dieback
• Australian vineyards
• fungal phytotoxins
• melleins
• tyrosol

Acknowledgements

This manuscript was in part supported by academic grants from the Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Italy and the National Wine Grape Industry Centre, Charles Sturt University, Australia. Antonio Evidente is associated with ‘Istituto di Chimica Biomolecolare del CNR’, Pozzuoli, Italy.

Disclosure statement

No potential conflict of interest was reported by the authors.