Influence of Soil Chemical Features on Aromatic Profile of V. vinifera cv. Corvina Grapes and Wines: A Study-Case in Valpolicella Area (Italy) in a Calcareous and Non-Calcareous Soil

In the Valpolicella area (Verona, Italy) one of the most important Italian wines is being produced: Amarone, predominately made by Vitis vinifera cv. Corvina. This wine is subjected to a specific postharvest process, namely, withering, which aims to increase alcohol content and/or high residual sugars while retaining richness in aromas and organoleptic compounds. In accordance with guidelines and strict Amarone protocol set by the Consorzio of Amarone-Valpolicella, withering must be carried out by setting the grapes in a suitable environment. In our study, the withering process was performed following the traditional methods, i.e., in open-air, natural environmental conditions, as generally performed by winegrowers, leading to a weight loss in grapes of up to 30%. Whilst the effect of different postharvest conditions is clear and studied, it is interesting to know how soil can affect both grapes and wine profile, in terms of aromas, which are of great importance for this crafted wine. For this purpose, for two study years, the influence of two different sites (with regards to the carbonates’ content) on aromas were investigated. Furthermore, microvinifications and the sensory profile of the resulting wines were analysed. Our results clearly indicated that different soils’ characteristics, particularly differences in carbonate content, had an important effect, not only on the aromatic compounds of grapes and wines, but on the sensory profile as well. This information will help winegrowers and winemakers in the process of determining site selection for future vineyards in order to obtain a final optimum Amarone wine, in terms of its aromatic composition—one that is able to respond to the market demand

Fertigation affects photosynthesis, modulation of secondary metabolism and sensory profiles of Vitis vinifera cv. “Schioppettino” withered grapes and wines

Nowadays a balance in plant production is required, especially in terms of nutrition, yield and for an optimal aroma and sensory profile of resulted wines. In this research, we compared two different methods of plant nutrition: one-single application (single-fertilization-SF) and two applications with the same amount adopting the fertigation (split fertigation-SpF), including a control not-treated, in a specific Italian region where grapevine Schiopettino cv. is being cultivated and this practice was not investigated yet. SpF promoted the photosynthesis parameters compared to a SF and to the non-treated vines (NTC). On these basis, the biological and physiological activity of the whole plant was enhanced. SpF treatment tendentially and significantly improved the qualitative, productive, physiological, and oenological parameters of “Schioppettino” wine

Compost application boosts soil restoration in highly disturbed hillslope vineyard

A field trial was carried out to investigate the effects of compost application on a young Cabernet sauvignon vineyard located in a hilly area in the North-East of Italy and subjected to land terracing before plantation. The use of a compost based on manure, pruning residues and pomace at a rate of 65 t ha-1 was compared to the mineral fertilization regime recommended for the vineyards in the area (NPK: 80, 50, 200 kg ha-1). A multi-factorial approach that considered soil chemical properties, microbial community structure and function, vine nutritional and vegetative indexes, yield and quality parameters was applied in the attempt of depict interrelated effects of compost on all these factors. Results of this study show that the application of compost for three consequent years greatly increased soil organic matter content and improved the mineral nutrient availability in the soil. Soil biological fertility showed a slow but significant response to compost addition as from the second year of treatment microbial growth and enzyme activity were increased compared to those of the inorganic fertilization, with special regard to enzymes involved in P cycle. A shift in the soil microbial community structure was also observed in compost-treated soil, with higher presence of copiotrophic bacteria, indicators of soil quality, and phosphorus solubilizing bacteria. A decrease of pathogenic fungal strains was also observed. Organic fertilization increased plant nutrient uptake and vegetative growth compared to those observed in chemically fertilized vines. A trend toward increased yield and improvements for some grape quality parameters such as acidity and pH were observed in the first year of production. These results provide evidence that compost can boost soil fertility restoration in vineyard disturbed by land terracing, allowing for agronomic performances comparable or even improved than those of chemically fertilized vines

Exploring the influence of soil salinity on microbiota dynamics in Vitis vinifera cv. “Glera”: insights into rhizosphere, carposphere, and yield outcomes

In a world grappling with the severe effects induced by climate change, one of the most significant concerns affecting agriculture is the gradual decline in water quality for irrigation associated to reduced rainfalls, and the consequent increase in soil salinity. This issue is particularly crucial for grapevine cultivation (Vitis vinifera L.) and the associated winemaking industry. The aroma of resulting wines and yield parameters can be influenced both directly by water quality and indirectly due to the effects exerted by salinity on the microbiota, which directly impacts plant health. To gain insights into this topic, our study aimed to analyse the changes induced in the microbiota of both the rhizosphere and carposphere due to salt stress using a metabarcoding approach, focusing on Vitis vinifera cv. Glera. Control plants were irrigated with rainwater, while treated plants were irrigated with water containing salt (NaCl). Our findings revealed significant differences in the microbiota (both fungi and bacteria) of the rhizosphere and carposphere between the two treatments. For instance, the Shannon diversity index (i.e., alfa-diversity) was lower in the treated plants compared to the control not-treated, whilst the beta-diversity did not show any differences. Several microbial phyla exhibited better resilience to this abiotic stress (e.g., Ascomycota, Saccharomycetes, Acidobacteria, Proteobacteria, Bacteroidetes), shedding light on their impact on crucial bacterial and fungal groups essential for subsequent winemaking stages. Additionally, the salt stress negatively affected yield parameters. This study contributes valuable insights to the viticultural community, providing a deeper understanding of the complex interplay between soil characteristics, microbial communities, and their influence on productivity

Tuning Potassium Fertilization to Improve pH and Acidity in Glera Grapevine (<i>Vitis vinifera</i> L.) under a Warming Climate

Potassium concentration in grape berries can affect acidity and pH in must and wines. Under the current warming scenario, where preserving equilibrated value for these grape parameters is increasingly challenging, K fertilization could represent a tool to manage grape composition. In this study, the effect of potassium fertilization was investigated over 4 years (2013–2016) in field-grown grapevines (Vitis vinifera cv. Glera). Four different potassium rates (0, 15, 30, 60 kg K2O ha−1 year−1) were tested and agronomic responses, grape quality as well as K concentration in the berry were recorded over the four years. At harvest, yield parameters and total soluble solids were unaffected by potassium fertilization. On the contrary, the titratable acidity of the musts was increased by the higher rate of potassium (K60), and both tartaric and malic acids showed higher values when the K rate was higher. K fertilization did not affect the pH, as all the treatments displayed comparable pH values and in an optimal range for winemaking. Overall, in our experimental conditions, medium potassium inputs showed better results on Glera grape quality compared to low K rates, by promoting higher titratable acidity levels without altering the pH in musts

Tuning Potassium Fertilization to Improve pH and Acidity in Glera Grapevine (Vitis vinifera L.) under a Warming Climate

Potassium concentration in grape berries can affect acidity and pH in must and wines. Under the current warming scenario, where preserving equilibrated value for these grape parameters is increasingly challenging, K fertilization could represent a tool to manage grape composition. In this study, the effect of potassium fertilization was investigated over 4 years (2013&ndash;2016) in field-grown grapevines (Vitis vinifera cv. Glera). Four different potassium rates (0, 15, 30, 60 kg K2O ha&minus;1 year&minus;1) were tested and agronomic responses, grape quality as well as K concentration in the berry were recorded over the four years. At harvest, yield parameters and total soluble solids were unaffected by potassium fertilization. On the contrary, the titratable acidity of the musts was increased by the higher rate of potassium (K60), and both tartaric and malic acids showed higher values when the K rate was higher. K fertilization did not affect the pH, as all the treatments displayed comparable pH values and in an optimal range for winemaking. Overall, in our experimental conditions, medium potassium inputs showed better results on Glera grape quality compared to low K rates, by promoting higher titratable acidity levels without altering the pH in musts

Error Autocorrelation and Linear Regression for Temperature-Based Evapotranspiration Estimates Improvement

Estimates of evapotranspiration on a local scale is important information for agricultural and hydrological practices. However, equations to estimate potential evapotranspiration based only on temperature data, which are simple to use, are usually less trustworthy than the Food and Agriculture Organization (FAO)Penman-Monteith standard method. The present work describes two correction procedures for potential evapotranspiration estimates by temperature, making the results more reliable. Initially, the standard FAO-Penman-Monteith method was evaluated with a complete climatologic data set for the period between 2002 and 2006. Then temperature-based estimates by Camargo and Jensen-Haise methods have been adjusted by error autocorrelation evaluated in biweekly and monthly periods. In a second adjustment, simple linear regression was applied. The adjusted equations have been validated with climatic data available for the Year 2001. Both proposed methodologies showed good agreement with the standard method indicating that the methodology can be used for local potential evapotranspiration estimates.Brazilian National Research Council (CNPq/Brazil)Brazilian National Research Council (CNPq/Brazil

Impronta territoriale di un prodotto alimentare. La ricerca dell’Università di Ferrara in difesa del Made in Italy

L’Università di Ferrara ha lavorato negli ultimi anni su metodologie innovative di analisi geochimiche per la valutazione della qualità dei prodotti agricoli italiani: mele, pere, graminacee e vino. La ricerca è rivolta principalmente alla difesa del made in Italy e alla tutela dei prodotti di origine protetta. Adesso, con il progetto “Territorialità del Prosecco”, il team costituito da: Salvatore Pepi, Luigi Sansone, Diego Tomasi, Patrick Marcuzzo e Stefano Soligo e coordinato dalla professoressa Carmela Vaccaro del Dipartimento di Fisica e Scienze della terra dell’Università di Ferrara ha messo a punto un innovativo metodo di analisi, finalizzato a definire l'unicità di uve e vini, applicato ad uno dei più importanti distretti viti-vinicoli italiani. Il Prosecco è un vino di eccellenza, la cui denominazione fa riferimento a un territorio definito e a un certo numero di cantine e di aziende vinicole. Data la notevole richiesta del mercato, si sono rese necessarie misure di controllo che evitino contraffazioni, tagli delle uve, usi impropri o illeciti della denominazione. In sintesi, attraverso una serie di analisi integrate che riguardano il suolo, la composizione del prodotto (uva e vino) e le sue caratteristiche qualitative, è stato possibile definire “ l’impronta territoriale” del Prosecco, ovvero le caratteristiche che un vino deve avere, se è stato davvero prodotto nel territorio e nelle cantine che fanno parte del distretto. L’analisi del suolo riguarda le caratteritiche geochimiche del terreno, la sua tessitura, l’impronta climatica. L’analisi della composizione chimica consente il riconoscimento del prodotto e l’individuazione delle quantità di elementi minerali (calcio, magnesio, sodio, potassio, ferro, etc.) che lo caratterizzano. La stessa analisi consente di individuare la presenza o l’assenza di componenti con caratteri di tossicità, che contribuiscono a definire la qualità del prodotto. I risultati di queste analisi costituiscono “ l’impronta territoriale ” del prodotto, impronta che non può essere falsificata. Un vino prodotto con uve provenienti da altri territori, o anche solo tagliato con uve diverse, non può avere la stessa composizione chimica del Prosecco originale, anche se solo all’apparenza la qualità è uguale. La metodologia applicata per la definizione dell’impronta territoriale” consente valutazioni molto mirate, al punto che sullo stesso territorio i prodotti di imprese vinicole differenti hanno impronte diverse. Al termine del progetto, dopo una fase di caratterizzazione dei prodotti di ogni cantina, ogni impresa vinicola della zona di produzione avrà la propria impronta territoriale, informazione che potrà in futuro entrare nell’etichetta e tutelare il prodotto finito

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