Sensorial potential of new fungi-resistant varieties in modern oenology

Context and purpose of the study – The introduction into the Italian wine supply chain of the latest generation of fungi-resistant grapevine varieties, endowed with a greater or lesser strong resistance to downy and powdery mildews, represents a valid tool of making viticulture more sustainable, particularly in northern regions of the peninsula, where climatic conditions accentuate the pressure of fungal diseases However, the affirmation of resistant varieties is a function of their agronomic value, as well as of their oenological and sensorial value. The purpose of this study was to evaluate in detail the sensory potential of the new resistant varieties, in order to understand their real possibility of inclusion in the modern global enological context. Material and methods – The research involved the sensory analysis of 29 resistant wines from two vintages (2019 and 2020), plus 2 control wines (Pinot bianco and Pinot noir), carried out by a trained panel. Samples were anonymized with numerical codes, to ensure anonymous evaluations, and randomized. Additionally, a replicate sample was introduced into each block. The work plan envisaged a first step in which a special file was created to identify the salient qualitative and quantitative characteristics of wines from resistant grape varieties. The descriptors usually used in the sensory cards have been integrated with the dominant descriptors identified by the panelists, in particular floral, fruity, vegetable, spicy and the foxy note characteristic of the non-noble breeding parent. The sensory analysis data were processed with descriptive and parametric techniques in order to identify specificities with significant and potentially usable differences for the creation of new brands or blends with traditional varieties. Results – An analysis of the sensory characteristics of wines obtained from the latest generation of resistant varieties was carried out. The general characteristics typical of each resistant wine have been highlighted, yet interesting sensory potential for both white and red wines was found, at any rate variability between varieties arose. In general, results obtained are promising and can be used to define the criteria for a gradual diffusion of these new varieties. In particular, the identification of some dominant descriptors for the olfactory part will be used to manage the viticultural and oenological techniques, in order to optimize the most interesting sensory characteristics of the resistant varieties, limiting the perception of the Volpino flavour, that has been perceived. The sensory data can also be used to define the possibilities of vinification in purity, or in blends, of the new generation resistant varieties. In general, the results confirm the possibility of using the new resistant varieties as a tool for a real low-impact viticulture

Grapevine red blotch virus is sporadically present in a germplasm collection in Northern Italy

Limited information is available on the distribution of grapevine red blotch virus (GRBV) in grape-growing regions outside North America. In this study, the presence of GRBV was investigated in 596 grapevine samples coming from different sources in Northern Italy, including rootstock and table grape accessions from ampelographic collections, and commercial varieties with red blotch-like symptoms. Only ‘Queen’ and ‘Incrocio Dalmasso VIII-5’ accessions, collected from the CREA-Viticulture and Enology repository of table grape varieties, tested positive for GRBV. Sequencing of fragments from replication and coat protein genes revealed that the two accessions were infected with GRBV isolates belonging to two distinct lineages. While the American origin of ‘Queen’ could explain the GRBV presence in this accession, the viral infection of the Italian ‘Incrocio Dalmasso VIII-5’ remains an unsolved mystery