Vitis vinifera is one of the most sensitive species to climate-change induced stresses, such as drought. Whether on one side it is crucial to understand how grape cultivars physiologically perceive and react to adverse climate conditions, on the other side it is necessary to improve existing breeding platforms using sustainable techniques allowing the selection of resilient genotypes. Somatic embryogenesis (SE) (i.e. the initiation of embryos from somatic tissues) represents a powerful green biotechnological tool for genetic improvement purposes. SE can spontaneously generate new genetic variability, called somaclonal variation, which results from genetic mutations, changes in epigenetic marks altering transposon activity and/or gene expression, or phenotypic alterations. This study was tailored to demonstrate whether vines in vitro regenerated through SE, namely somaclones, can endure water stress conditions better than the mother plant. A severe water deficit treatment was thereby imposed on a population of different somaclone lines of Vitis vinifera 'Nebbiolo' and on the corresponding mother plant line. During the trial, the main ecophysiological parameters (e.g. gas exchanges, relative water content, stem water potential) were monitored. Changes in biometric and anatomical traits were also inspected. Collected data allowed to identify those lines with improved tolerance to water stress. To deepen the mechanisms underlying the observed tolerance, biochemical and molecular analyses are ongoing to profile changes in the content of defense secondary metabolites and hormones and in the transcription of stress-responsive genes. In parallel, the genomes of the best and worst performing lines have also been sequenced.

Plasmopara viticola, the agent of grapevine downy mildew, causes enormous economic damage, and its control is primarily based on the use of synthetic fungicides. The European Union policies promote reducing reliance on synthetic plant protection products. Biocontrol agents such as Trichoderma spp. constitute a resource for the development of biopesticides. Trichoderma spp. produce secondary metabolites such as peptaibols, but the poor water solubility of peptaibols limits their practical use as agrochemicals. To identify new potential bio-inspired molecules effective against P. viticola, various water-soluble peptide analogs of the peptaibol trichogin were synthesized. In grapevine leaf disk assays, the peptides analogs at a concentration of 50 mu M completely prevented P. viticola infection after zoosporangia inoculation. Microscopic observations of one of the most effective peptides showed that it causes membrane lysis and cytoplasmic granulation in both zoosporangia and zoospores. Among the effective peptides, 4r was selected for a 2-year field trial experiment. In the vineyard, the peptide administered at 100 mu M (equivalent to 129.3 g/ha) significantly reduced the disease incidence and severity on both leaves and bunches, with protection levels similar to those obtained using a cupric fungicide. In the second-year field trial, reduced dosages of the peptide were also tested, and even at the peptide concentration reduced by 50 or 75%, a significant decrease in the disease incidence and severity was obtained at the end of the trial. The peptide did not show any phytotoxic effect. Previously, peptide 4r had been demonstrated to be active against other fungal pathogens, including the grapevine fungus Botrytis cinerea. Thus, this peptide may be a candidate for a broad-spectrum fungicide whose biological properties deserve further investigation.

Flavescence doree is an economically important vector-borne disease of grapevine in Europe caused by phytoplasmas belonging to the 16SrV ribosomal group. Expression profiles of 11 genes of the Flavescence doree phytoplasma (FDp) were analysed over time following infection of natural (Vitis vinifera and the leafhopper vector Scaphoideus titanus) and experimental (Vicia faba and Euscelidius variegatus) hosts. Infected and symptomatic grapevine plants (Chardonnay) were sampled under natural field conditions in a productive vineyard in north-western Italy. Broad bean samples were assayed after the experimental inoculation with infectious E. variegatus. Adults of both vector species were analyzed following FDp acquisition from infected broad bean plants. The selected FDp genes were grouped according to their putative functions within different categories, namely 'Membrane proteins' (imp), 'Regulative elements' (spoVG, rpoD), 'Protein metabolism, transport and secretion' (tldD, ysdC, ftsY), 'Stress response' (comp83, osmC), 'ABC transporters' (CoABC) and 'Unknown' function (contig12, comp115). All analyzed genes were expressed in the four different host species suggesting their crucial role during the FDp infection cycle. Moreover, some of them (contig12, CoABC, comp83, and imp) might be considered essential for phytoplasma survival irrespective of the host, while comp115 seems to be required for insect infection. We showed that FDp is metabolically more active in insects than in plants, at least according to the pool of selected genes for this study, indicating that FDp behaves differently in the two hosts compared to other phytoplasma species/strains.

Sexual reproduction has contributed to a significant degree of variability in cultivated grapevine populations. However, the additional influence of spontaneous somatic mutations has played a pivotal role in shaping the diverse landscape of grapevine agrobiodiversity. These naturally occurring selections, termed 'clones,' represent a vast reservoir of potentially valuable traits and alleles that hold promise for enhancing grape quality and bolstering plant resilience against environmental and biotic challenges. Despite their potential, many of these clones remain largely untapped.In light of this context, this study aims to delve into the population structure, genetic diversity, and distinctive genetic loci within a collection of 138 clones derived from six Campanian and Apulian grapevine varieties, known for their desirable attributes in viticulture and winemaking. Employing two reduced representation sequencing methods, we extracted Single-Nucleotide Polymorphism (SNP) markers. Population structure analysis and fixation index (FST) calculations were conducted both between populations and at individual loci. Notably, varieties originating from the same geographical region exhibited pronounced genetic similarity.The resulting SNP dataset facilitated the identification of approximately two hundred loci featuring divergent markers (FST >= 0.80) within annotated exons. Several of these loci exhibited associations with essential traits like phenotypic adaptability and environmental responsiveness, offering compelling opportunities for grapevine breeding initiatives. By shedding light on the genetic variability inherent in these treasured traditional grapevines, our study contributes to the broader understanding of their potential. Importantly, it underscores the urgency of preserving and characterizing these valuable genetic resources to safeguard their intra-varietal diversity and foster future advancements in grapevine cultivation.

Along with the ongoing climate change, drought events are predicted to become more severe. In this context, the spray-induced gene silencing (SIGS) technique could represent a useful strategy to improve crop stress resilience. A previous study demonstrated that the Arabidopsis mutants for a glutathione S-transferase (GST) gene had increased abscisic acid (ABA) levels and a more activated antioxidant system, both features that improved drought resilience. Here, we used SIGS to target a putative grape GST gene (VvGST40). Then, ecophysiological, biochemical and molecular responses of 'Chardonnay' cuttings were analysed during a drought and recovery time-course. Gas exchange, ABA and t-resveratrol concentration as well as expression of stress-related genes were monitored in not treated controls, dsRNA-VvGST40- and dsRNA-GFP- (negative control of the technique) treated plants, either submitted or not to drought. VvGST40-treated plants revealed increased resilience to severe drought as attested by the ecophysiological data. Analysis of target metabolites and antioxidant- and ABA-related transcripts confirmed that VvGST40-treated plants were in a priming status compared with controls. SIGS targeting an endogenous gene was successfully applied in grapevine, confirming the ability of this technique to be exploited not only for plant protection issues but also for functional genomic studies.

Scaphoideus titanus (Ball) is a Nearctic leafhopper (Cicadellidae: Deltocephalinae), monophagous on Vitis spp., naturalized in European vineyards since the 20th century. Following its introduction and establishment in Europe, S. titanus became the main vector of Flavescence dorée phytoplasma (FDp) to grapevine. FDp causes heavy economic losses to viticulture in Europe. The control of the disease mainly relies on insecticide applications against the vector and on the removal of infected plants. The exploitation of plant resistance or tolerance against pathogens and pests can represent a valuable tool for a more sustainable viticulture. The first step in identifying resistance traits in grapevine varieties towards S. titanus is the evaluation of insect fitness parameters on different grapevine genotypes. Therefore, in this work, nymph mortality and developmental time, adult survival and prolificacy of S. titanus have been studied on three grapevine varieties, characterized by different susceptibility to FD. Scaphoideus titanus showed highest fitness when reared on Barbera, whereas the worst performances were recorded on Moscato, with a significant reduction in nymph and adult survivals, a slowed nymph development, and a decreased number of available eggs. On Brachetto, S. titanus showed an intermediate level of fitness parameters. Consistently with previous studies on feeding behaviour, Barbera is the most suitable host for the FD-vector. The high suitability of Barbera for S. titanus may partly explain the high susceptibility to FD of this variety. On the contrary, the low suitability of Moscato, poorly susceptible to FD, may be due to antibiosis and antixenosis defence mechanisms that act against S. titanus.

The progressive reduction in the quantities of copper regulated by the European Union is focusing the research on new formulations with a reduced copper content but equally effective. In this regard, the activity of an Italian copper chabasite-rich zeolitite, which proved to be effective against grapevine grey mold and sour rot, was assessed against downy mildew. A two-year study was carried out in the Abruzzo region, Italy, in a cv. Montepulciano vineyard. The applications of the copper zeolitite showed the same good results obtained by a standard integrated/conventional strategy based on contact and systemic fungicides. At harvest, in both trial years, the plants with infected bunches in the untreated control ranged from 86.25% to 100%, compared to 15-30% of the treated plants. Furthermore, infected bunches and berries of the untreated control vines were 70-100% while treated ones never exceeded 2.32%. Furthermore, an increase in the polyphenol content and color intensity in wines made from vines treated with copper zeolitite was confirmed and appeared to be particularly evident in hot and dry seasons. The activity of copper zeolitite towards downy mildew, the potential use against grey mold and sour rot and the protection of grapes from high temperatures indicate that this product is a promising tool for a viticulture environmentally friendly control strategy.

Grapevine is one of the most cultivated fruit plant among economically relevant species in the world. It is vegetatively propagated and can be attacked by more than 80 viruses with possible detrimental effects on crop yield and wine quality. Preventive measures relying on extensive and robust diagnosis are fundamental to guarantee the use of virus-free grapevine plants and to manage its diseases. New phenotyping techniques for non-invasive identification of biochemical changes occurring during virus infection can be used for rapid diagnostic purposes. Here, we have investigated the potential of Raman spectroscopy (RS) to identify the presence of two different viruses, grapevine fan leaf virus (GFLV) and grapevine rupestris stem pitting-associated virus (GRSPaV) in Vitis vinifera cv. Chardonnay. We showed that RS can discriminate healthy plants from those infected by each of the two viruses, even in the absence of visible symptoms, with accuracy up to 100 and 80% for GFLV and GRSPaV, respectively. Chemometric analyses of the Raman spectra followed by chemical measurements showed that RS could probe a decrease in the carotenoid content in infected leaves, more profoundly altered by GFLV infection. Transcriptional analysis of genes involved in the carotenoid pathway confirmed that this biosynthetic process is altered during infection. These results indicate that RS is a cutting-edge alternative for a real-time dynamic monitoring of pathogens in grapevine plants and can be useful for studying the metabolic changes ensuing from plant stresses.

In grapevines, as in other plants, sucrose and its constituents glucose and fructose are fundamentally important and carry out a multitude of roles. The aims of this review are three-fold. First, to provide a summary of the metabolism and transport of sucrose in grapevines, together with new insights and interpretations. Second, to stress the importance of considering the compartmentation of metabolism. Third, to outline the key role of acid invertase in osmoregulation associated with sucrose metabolism and transport in plants.

Aims: Soil microbiome roles in agriculture is becoming more and more important. This importance is also reflected on the way plants are seen: complex organisms formed by the plant itself plus the microbes inhabiting its tissues, including the ones on the surface of every organ and the ones adhered or in proximity to the roots. In addition, as already demonstrated, the microbial community associated with a specific soil is able to predetermine the health status of crops. For all the above mentioned reasons, defining the microbial composition of agricultural soils and the factors driving the assemblage is pivotal to achieve more sustainable agriculture and viticulture. Methods: We aimed to investigate how the soil geological characteristics influence the microbiome composition associated with close geographically related vineyards. Moreover, we studied both the top (15 cm in depth) and deep (120 cm in depth) soil layers as anthropically influenced and almost-undisturbed soil, respectively. Results: We observed slightly different microbial communities despite the close geographical proximity of the two vineyards, which is considered one of the main determinants of the soil microbiome composition. In addition, we found that the geological characteristics of the two soils influence both the root distribution and the accumulation of pathogen- and symbiont-related genera. Sensory profiles of the Grillo wines from the two different soils confirmed the tight link between soil origin and wine traits. Conclusions: In the present study, we highlight that the geological characteristics of soil can influence soil microbial composition and assemblage in close geographically related vineyards, with a potential effect on wine features.

Vitis vinifera represents an important and renowned source of compounds with significant biological activity. Wines and winery bioproducts, such as grape pomace, skins, and seeds, are rich in bioactive compounds against a wide range of human pathogens, including bacteria, fungi, and viruses. However, little is known about the biological properties of vine leaves. The aim of this study was the evaluation of phenolic composition and antiviral activity of Vitis vinifera leaf extract against two human viruses: the Herpes simplex virus type 1 (HSV-1) and the pandemic and currently widespread severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). About 40 phenolic compounds were identified in the extract by HPLC-MS/MS analysis: most of them were quercetin derivatives, others included derivatives of luteolin, kaempferol, apigenin, isorhamnetin, myricetin, chrysoeriol, biochanin, isookanin, and scutellarein. Leaf extract was able to inhibit both HSV-1 and SARS-CoV-2 replication in the early stages of infection by directly blocking the proteins enriched on the viral surface, at a very low concentration of 10 ?g/mL. These results are very promising and highlight how natural extracts could be used in the design of antiviral drugs and the development of future vaccines.

Background: Grapevine reproductive development has direct implications on yield. It also impacts on berry and wine quality by affecting traits like seedlessness, berry and bunch size, cluster compactness and berry skin to pulp ratio. Seasonal fluctuations in yield, fruit composition and wine attributes, which are largely driven by climatic factors, are major challenges for worldwide table grape and wine industry. Accordingly, a better understanding of reproductive processes such as gamete development, fertilization, seed and fruit set is of paramount relevance for managing yield and quality. With the aim of providing new insights into this field, we searched for clones with contrasting seed content in two germplasm collections. Results: We identified eight variant pairs that seemingly differ only in seed-related characteristics while showing identical genotype when tested with the GrapeReSeq_Illumina_20K_SNP_chip and several microsatellites. We performed multi-year observations on seed and fruit set deriving from different pollination treatments, with special emphasis on the pair composed by Sangiovese and its seedless variant locally named Corinto Nero. The pollen of Corinto Nero failed to germinate in vitro and gave poor berry set when used to pollinate other varieties. Most berries from both open- and cross-pollinated Corinto Nero inflorescences did not contain seeds. The genetic analysis of seedlings derived from occasional Corinto Nero normal seeds revealed that the few Corinto Nero functional gametes are mostly unreduced. Moreover, three genotypes, including Sangiovese and Corinto Nero, were unexpectedly found to develop fruits without pollen contribution and occasionally showed normal-like seeds. Five missense single nucleotide polymorphisms were identified between Corinto Nero and Sangiovese from transcriptomic data. Conclusions: Our observations allowed us to attribute a seedlessness type to some variants for which it was not documented in the literature. Interestingly, the VvAGL11 mutation responsible for Sultanina stenospermocarpy was also discovered in a seedless mutant of Gouais Blanc. We suggest that Corinto Nero parthenocarpy is driven by pollen and/or embryo sac defects, and both events likely arise from meiotic anomalies. The single nucleotide polymorphisms identified between Sangiovese and Corinto Nero are suitable for testing as traceability markers for propagated material and as functional candidates for the seedless phenotype.

Irrigation with saline water is practiced in countries prone to water scarcity, in arid and semi-arid climates. In a Mediterranean climate (Sicily, southern Italy), transpiration and canopy resistance were determined in a vineyard (Syrah grafted on Paulsen 1103) irrigated with water at two salinity levels. One section of the experimental plot was irrigated with water of low salinity (electrical conductivity ECw = 0.6 dS m-1); the other section received irrigation water at higher salinity level (ECw = 1.6 dS m-1). Actual vines transpiration was measured by a thermal dissipation sap flow method, in two growing seasons (2008 and 2009). Canopy transpiration (Tr) and resistance (rc), the latter calculated using the Penman-Monteith equation, were analyzed on hourly and daily time scale. Moreover, the trends in canopy resistance were evaluated in relation to main micrometeorological variables (global radiation and vapor pressure deficit). In the ECw 1.6 treatment, canopy transpiration was lower and its values, cumulated through the experimental period, were 20% and 16% lower than in the ECw 0.6 treatment, in 2008 and 2009, respectively. A rudimentary estimate of the relationship between cumulated canopy transpiration and soil salinity was also made, and a threshold value of relative transpiration was identified at soil electrical conductivity (ECe) = 1.4 dS m-1. Hourly values of rc in ECw 1.6 were higher than in ECw 0.6 and the response patterns of rc to global radiation and to vapor pressure deficit were different at different salinity levels.

The Italian grape germplasm is characterized by a high level of richness in terms of varieties number, with nearly 600 wine grape varieties listed in the Italian National Register of Grapevine Varieties and with a plethora of autochthonous grapes. In the present study an extended SNP genotyping has been carried out on Italian germplasm of cultivated Vitis vinifera subsp. sativa and Vitis hybrids. Several hundred Italian varieties maintained in the repositories of scientific Institutions and about one thousand additional varieties derived from previous studies on European, Southern Italy, Magna Graecia and Georgian germplasm were considered. The large genotyping data obtained were used to check the presence of homonyms and synonyms, determine parental relationships, and identify the main ancestors of traditional Italian cultivars and closely-related accessions. The parentage among a set of 1,232 unique varieties has been assessed. A total of 92 new parent-offspring (PO) pairs and 14 new PO trios were identified. The resulted parentage network suggested that the traditional Italian grapevine germplasm originates largely from a few central varieties geographically distributed into several areas of genetic influence: "Strinto porcino" and its offspring "Sangiovese", "Mantonico bianco" and "Aglianico" mainly as founder varieties of South-Western Italy (IT-SW); Italian Adriatic Coast (IT-AC); and Central Italy with most varieties being offsprings of "Visparola", "Garganega" and "Bombino bianco"; "Termarina (Sciaccarello)" "Orsolina" and "Uva Tosca" as the main varieties of North-Western Italy (IT-NW) and Central Italy. The pedigree reconstruction by full-sib and second-degree relationships highlighted the key role of some cultivars, and, in particular, the centrality of "Visparola" in the origin of Italian germplasm appeared clear. An hypothetical migration of this variety within the Italian Peninsula from South to North along the eastern side, as well as of "Sangiovese" from South to Central Italy along the Western side might be supposed. Moreover, it was also highlighted that, among the main founders of muscat varieties, "Moscato bianco" and "Zibibbo (Muscat of Alexandria)" have spread over the whole Italy, with a high contribution by the former to germplasm of the North-Western of the peninsula.

Grape canes from Vitis vinifera L. cultivars of Campania region (Italy): "Aglianico", "Fi-ano", and "Greco" were considered in order to valorise them through the extraction of phenolic compounds provided with antioxidant activity. Since many operational parame-ters influence the extraction process, here different extraction conditions were compared. Grape canes (5% w/v) were extracted in water at different temperatures (25, 50, 75 and 100°C) and extraction times (10, 20, 40 and 60 min). The highest yields, in terms of mg/g dry extract, were obtained by "Greco" at 100°C and 20 min: 110.51±5.46 for total phe-nols, 63.29±1.35 for ortho-diphenols, 77.31±3.59 for tannins, and by "Greco" at 50°C and 40 min for flavonoids: 29.37±0.73. The extracts from "Greco" at different tempera-tures showed antioxidant activity comparable to that of butylhydroxytoluene and querce-tin chosen as reference compounds. HPLC analysis revealed that gallic acid and catechin were the most abundant phenolic compounds detected in the extracts.

The early defoliation of the fruiting area is a technique that offers considerable advantages both in relation to the quality of grapes and to pest control; on the other hand, when a very warm summer occurs, the risk of grape sunburn may increase. This paper reports the results of a pre-flowering defoliation trial carried out in the province of Arezzo (Italy) in 2017, an exceptionally hot and dry year. The results confirmed the validity of this technique in limiting yield while achieving a concurrent higher concentration of phenolic compounds without increasing the risk of burns and radiative damages of grapes.

The rise in air temperature due to climate change is causing an increase in the sugar accumulation rate in grape berries, resulting in increased wine alcohol concentrations. Postveraison leaf area removal (defolia-tion, shoot-trimming) is a suitable canopy management strategy to slow carbohydrate accumulation in the berries. However, in late-ripening cultivars, the phenological stage between veraison onset and harvest can be very long. Therefore, it can be hypothesized that the specific timing when leaf area removal is applied during the phenological stage can affect carbohydrate accumulation in the berries and berry composition. A two-year experiment was designed to compare the responses of Aglianico grapevines, a late-maturing cultivar, to shoot-trimming applied at three different stages of berry ripening. The experimental design included: (a) three trimming treatments applied at total soluble solids of 6, 12, and 18 Brix, respectively; and (b) a control treatment (untrimmed vines). Independent of the application timing, shoot-trimming decreased berry total soluble solids at harvest below that of control vines, but the later the shoot-trimming was applied, the lower berry total soluble solids was at harvest. Shoot-trimming did not affect other berry parameters. These results confirm that, at least for late-maturing cultivars, the timing of application of late shoot-trimming plays a key role in modulating the intensity of the effects of this management practice on berry composition.

Noble rot is a latent infection of grape berries caused by the necrotrophic fungus Botrytis cinerea, which develops under specific climatic conditions. The infected berries undergo biochemical and metabolic changes, associated with a rapid withering, which altogether offer interesting organoleptic features to sweet white wines. In this paper, we provide RNAseq datasets (raw and normalized counts as well as differentially expressed genes lists) of the transcriptome profiles of both grapevine berries (Vitis vinifera cv. Garganega) and B. cinerea during the establishment of noble rot, artificially induced in controlled conditions. The sequencing data are available in the NCBI GEO database under accession number GSE116741. These data were exploited in a comprehensive meta-analysis of gene expression during noble rot infection, gray mold and post-harvest withering. This highlighted an important common transcriptional reprogramming in different botrytized grape berry varieties and led to the identification of key genes specifically modulated during noble rot infection, which are described in the article entitled "Specific molecular interactions between Vitis vinifera and Botrytis cinerea are required for noble rot development in grape berries" Lovato et al., 2019. (c) 2019 The Authors. Published by Elsevier Inc.

In the table grape (Vitis vinifera) market, seedlessness is greatly prized by consumers of fresh fruits, thus causing an ever increasing demand of seedless varieties in recent years. Two kinds of seedlessness are known in grapevine: the partenocarpy, for which ovary is stimulated to develop without ovule fertilization (small size berries are formed and they are usually used for raisin production), and the stenospermocarpy, in which fertilization normally occurs, but embryo prematurely aborts and seed development stops (normal size berries, compatible with commercial requirement, are able to develop). Seedlessness is the result of complex developmental processes modified by genetic, physiological and environmental factors. Three independent and complementary recessive genes regulated by a dominant locus, named SDI (Seed Development Inhibitor), seem to be involved in the genetic control of the stenospermocarpic seed abortion in commercial grapevine cultivars. A MADS-box locus (VvAGL11) has been proposed as the major functional candidate for grape seedlessness; it also includes a (GAGA)n motif, proposed as the most useful molecular marker in breeding program. The use of this intragenic microsatellite for Marker Assisted Selection (MAS) is an extremely effective method to accelerate and simplify the selection processes of interesting genotypes, especially with regard to traits with tardive phenotypic manifestation as seedlessness. In this research two different strategies for SSR analysis have been compared: I) capillary electrophoresis e II) High Resolution Melting (HRM). Parameters such as simplicity, accurateness, sensitiveness, specificity and costs have been evaluated. Moreover, a CAPS marker, known to co-localized with VvAGL11 and to be fully linked to the presence of seedless haplotype, has been applied for genotyping the analysed cultivars.

"Several research studies were focused to understand how grapevine cultivars respond to environment; nevertheless, the biological mechanisms tuning this phenomenon need to be further deepened. Particularly, the molecular processes underlying the interplay between clones of the same cultivar and environment were poorly investigated. To address this issue, we analyzed the transcriptome of berries from three ""Nebbiolo"" clones grown in different vineyards, during two ripening seasons. RNA-sequencing data were implemented with analyses of candidate genes, secondary metabolites, and agronomical parameters. This multidisciplinary approach helped to dissect the complexity of clone × environment interactions, by identifying the molecular responses controlled by genotype, vineyard, phenological phase, or a combination of these factors. Transcripts associated to sugar signalling, anthocyanin biosynthesis, and transport were differently modulated among clones, according to changes in berry agronomical features. Conversely, genes involved in defense response, such as stilbene synthase genes, were significantly affected by vineyard, consistently with stilbenoid accumulation. Thus, besides at the cultivar level, clone-specific molecular responses also contribute to shape the agronomic features of grapes in different environments. This reveals a further level of complexity in the regulation of genotype × environment interactions that has to be considered for orienting viticultural practices aimed at enhancing the quality of grape productions."