Comprehensive polyphenolic profiling in promising resistant grapevine hybrids including seventeen novel breeds in Northern Italy

Background: A promising way to overcome the susceptibility of Vitis vinifera L. against fungal diseases is the integration of genetic resistance by the interspecific crossing between V. vinifera varieties and resistant species. However, products of such hybrids are still missing acceptance by customers particularly due to their organoleptic characteristics, not least influenced by their polyphenolic profile.

Results: Fifty-eight resistant breeding lines, forty-one from international programs and seventeen new progeny individuals, were grown in one untreated vineyard to exclude any variances by climatic and pedologic conditions or vine yarding practice. Sixty polyphenols, including acids, anthocyanins, flavonols, flavan-3-ols and stilbenoids, were determined in grapevine berries by Ultra High-Performance Liquid Chromatography - Mass Spectrometry (UHPLC-MS/MS) in two consecutive years. The overall profiles were rather consistent (variation p>0.05) within the two harvests, with exception of epicatechin and caftaric acid. Anthocyanin-diglucosides were found in ten of the red breeding lines, malvidin-3,5-O-diglucoside being predominant in nine of them. Total polyphenol content was comparable of the unknown progeny individuals and international breeding lines with exception of significantly increased amounts of gallic acid and some flavonoids.

Conclusion: The hereby reported comprehensive study of the polyphenolic profile of hybrids from international breeding programs but also of new breeds from private initiatives, all cultivated in the same vineyard, shall support the selection of promising candidates for further breeding programs to overcome the impairment due to undesired sensory characteristics of new highly resistant varieties. This article is protected by copyright. All rights reserved.

Keywords: UHPLC-MS/MS; Vitis; grapes; polyphenols; resistant varieties; targeted metabolomics.