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Breeding programs for disease resistance were developed from the 19th century on, in both the old (Europe) and new world as a way to promote sustainable viticulture. The main results of breeding, in terms of disease resistance and grape (and wine) quality are described, ranging from the first American hybrids to the most recent varieties. The activity of some representative breeders is discussed and the current situation in Italy is reported. Productive, legislative, and commercial aspects for wine production are considered, especially for European Union where the wine sector is strongly regulated. The perspectives of breeding for disease resistance are discussed, including the new breeding techniques (Nbt) like cis-genesis and genome editing. The importance to interact with the society to make acceptable these innovations is emphasized. While less acceptance problems are expected with table grapes, raisins or rootstocks, more concerns might arise with wine grapes. The role of science is to give the legislator tools to cope with sustainability and to educate the society (from the grape grower to the wine consumer) to a correct understanding. Innovations can be a real advantage only if they are accepted by all the actors of the wine chain.

Floor management in organic viticulture plays a key role as weed suppression and soil health must be warranted through practices that minimise the recourse to extensive tillage and herbicides, while any resident vegetation or sown cover crop should exert moderate competition for water and nutrients towards the consociated vines. Lack of knowledge exists about the fraction of soil cover crop coverage (Scc) which might represent the best compromise between the above needs. A four-year study (2017–2020) was conducted in an organically managed cv. Barbera/420 A vineyard in the North-West of Italy, comparing five floor management treatments each having light tillage as the practice chosen to control the under trellis weed growth. Inter-row treatments were permanent grass (PG), tillage (T), alternate tillage and permanent grass every second mid-row (AGT), a variant of this last treatment, where the tilled mid-row was used for growing a temporary winter cover crop terminated in spring (AGC) and temporary grass (TG) where grass was disked post-harvest (mid-October) until natural growth resumption in late winter (mid-February). An assessment was made for soil profile and physicochemical composition, floristic analyses performed in T, PG, and TG treatments, vegetative growth, yield components, grape maturity at harvest, single leaf gas exchange as well as midday and pre-dawn leaf water potentials. While overall scant, mostly season-related differences were found for leaf function and water status, soil management heavily impacted vine performance. Year-round soil cover crop coverage (Scc) regressed towards total pruning weight/vine and yield/vine showed high linear correlation (R2 = 0.93) for pruning weight/vine (to be reduced by 38% at 75% Scc vs. 0% Scc of the T treatment), whereas yield/vine was quite poorly correlated (R2 = 0.21) showing a 15% decrease in PG vs. T. Regressing Scc vs total soluble solids (TSS), titratable acidity (TA), total anthocyanins and phenolics conc

Breeding technologies exploiting marker-assisted selection have accelerated the selection of new cross-bred pathogen-resistant grapevine varieties. Several genotypes have been patented and admitted to cultivation; however, while their tolerance to fungal diseases has been the object of several in vitro and field studies, their productive and fruit composition traits during ripening are still poorly explored, especially in warm sites. In this study, five white pathogen-resistant varieties (PRVs) listed as UD 80–100, Soreli, UD 30–080, Sauvignon Rytos, Sauvignon Kretos were tested over two consecutive seasons in a site with a seasonal heat accumulation of about 2000 growing degree days (GDDs), and their performances were compared to two Vitis vinifera L. traditional varieties, Ortrugo and Sauvignon Blanc. Berries were weekly sampled from pre-veraison until harvest to determine total soluble solids (TSS) and titratable acidity (TA) dynamics. All tested PRV exhibited an earlier onset of veraison and a faster sugar accumulation, as compared to Ortrugo and Sauvignon Blanc, especially in 2019. At harvest, Sauvignon Blanc was the cultivar showing the highest titratable acidity (8.8 g/L). Ortrugo and PRV varieties showed very low TA (about 4.7 g/L), with the exception of Sauvignon Rytos (6.5 g/L). However, data disclose that Sauvignon Rytos higher acidity at harvest relies on higher tartrate (+1.1 to +2.2 g/L, as compared to other PRV), whereas in Sauvignon Blanc, high TA at harvest is due to either tartaric (+1 g/L, compared to PRV) and malic (+2.5 g/L, compared to PRV) acid retention. Overall, Sauvignon Rytos is the most suited PRV to be grown in a warm climate, where retaining adequate acidity at harvest is crucial to produce high-quality white wines. Nevertheless, canopy and ripening management strategies must be significantly adjusted, as compared to the standard practice employed for the parental Sauvignon Blanc.

Precision viticulture allows identifying vineyard zones of similar performance and select fruit at harvest to enhance the overall quality. If selective harvesting (SH) does not exclude handpicking operations, it is undoubtedly more feasible on larger scale when performed mechanically. Although SH profitability has been already demonstrated in extensive viticulture, little information is available within the Italian context that covers small vineyards often featuring large orographic variability, soil heterogeneity and varietal diversity. Based on a pre-trial remotely-sensed vigor map (5 m resolution), the study was performed in a mature 1.5 ha Vitis vinifera L. 'Barbera' vineyard located in the Colli Piacentini wine district. NDVI values allowed identifying three vigor classes (LV = low, MV = medium and HV = high) with ground-truthing being performed over three years. Vine growth, yield, leaf nutritional status and fruit composition were measured while soil properties were also assessed in parallel. Experimental wines were made in triplicate and sensory analysis was performed by comparing vigor classes; an additional sample was made by mixing wines in different proportions according to yield per hectare to simulate traditional harvest. Results showed that HV was associated to heavier soils with higher fertility and water holding capacity, leading to higher leaf area (3.99 vs. 2.67 m2 vine‐1 recorded in LV), excessive crop load (6.99 vs. 3.37 kg vine‐1) and incomplete or delayed ripening (TSS: 20.7 vs. 24.9 °Brix; TA: 9.72 vs. 7.71 g L‐1; anthocyanins: 0.82 vs. 1.60 g kg‐1). LV wines were more colored with higher purple hues compared to HV; LV wines were also fuller body, more balanced and, occasionally, even more astringent than HV. SH can boost exploitation of vineyard variability in the Colli Piacentini area and grapes from the same parcel, used for producing young sparkling and barrel-aged still wines. Seasonal feasibility and economic convenience of SH need to b

Three vigor zones, identified in a Barbera vineyard by remote sensing at full canopy, were carefully ground-truthed to determine, over 2 years, the relative weight of soil factors in affecting within-field variability, and to investigate vigor zone influence on dry matter (DM) and nutrient partitioning into different vine organs. Regardless of season, high vigor (HV) achieved stronger vine capacity as total vegetative growth and yield while resulting in markedly less ripened fruits than low vigor (LV) vines. PCA analysis carried out on ten different soil and vine variables clearly separated the three vigor levels and the correlation matrix highlighted that the factors mostly contributing to HV were soil depth, soil K and P concentration, total available water, clay fraction and Nleaf concentration. Conversely, sand fraction was the main marker for LV. When annual DM retrieved in clusters, canes, leaves, and shoot clippings was calculated for each vigor level and expressed as content (i.e. kg/ha) there was a general decreasing trend moving from HV to LV. However, when DM partitioned to each organ was given on a relative basis (i.e. percentage over total) results were similar across vigor levels. Similarly, when nutrients were given as content (e.g. kg or g/ha) out of 120 within-vigor combinations (12 nutrients, 2 seasons, 5 organs), 65 showed a significant difference between HV and LV. Conversely, with data expressed on a concentration basis (i.e. % DM) the number of significant differences between the vigor level means fell to 15. The study strengthens the causal link between soil properties and intra-vineyard spatial variability and clarifies that patterns of dry matter and nutrient partitioning to different vine organs are mildly affected by vine vigor when referred on a relative basis.

Appropriate characterization of intra-parcel variability is a key element for the effective application of precision farming techniques. Nowadays there are many platforms available to end users differing for pixel spatial resolution and the type of acquisition (remote or proximal). A challenging aspect pertaining to remote sensing image acquisition in the vineyard ecosystem is that, in a large majority of cases, vegetation is discontinuous and single rows alternate with strips of either bare or grassed soil. In this paper, four different satellite platforms (Sentinel-2, Spot-6, Pleiades, and WorldView-3) having different spatial resolution and MECS-VINE® proximity sensor were compared in terms of accuracy at describing spatial variability. Vineyard mapping was coupled with detailed ground truthing of growth, yield, and grape composition variables. The analysis was conducted based on vigor indices (Normalized Difference Vegetation Index or Canopy Index) and using the Moran Index (MI) to assess the degree of spatial auto-correlation for the different variables. The results obtained showed a large degree of intra-plot variability in the main agronomic parameters (pruning weight CV: 33.86%, yield: 32.09%). The univariate Moran index showed a log-linear function relating MI coefficients to the resolution levels. Comparison between vigor indices and agronomic data showed that the highest bivariate MI was reached by Pleiades followed by MECS-VINE® which also did not exhibit the negative effect of the border pixel owing to the proximal scanning acquisition. Despite WorldView-3′ s high resolution (1.24 m pixel) allowing very detailed data imaging, the comparison with ground-truth data was not encouraging, probably due to the presence of pure ground pixels, while Sentinel-2 was affected by the oversized pixel at 10 m.

In zone frequentemente soggette a stress multipli estivi e per la combinazione con vitigni particolarmente sensibili alla carenza idrica, viti innestate su M4 hanno dimostrato di poter mantenere uno stato idrico migliore, una migliore funzionalità della chioma e una maggior efficienza di uso dell’acqua rispetto a viti innestate su portinnesti tradizionali

Nei mesi estivi caldi e siccitosi si può preservare l’integrità di foglie e acini in modo semplice ed economico con l’uso dell’argilla bianca caolino, meglio se calcinato. Per aumentare la permanenza in seguito alle piogge è utile addizionare opportuni adesivanti

In many viticulture regions, multiple summer stresses are occurring with increased frequency and severity because of warming trends. Kaolin-based particle film technology is a technique that can mitigate the negative effects of intense and/or prolonged drought on grapevine physiology. Although a primary mechanism of action of kaolin is the increase of radiation reflection, some indirect effects are the protection of canopy functionality and faster stress recovery by abscisic acid (ABA) regulation. The physiological mechanism underlying the kaolin regulation of canopy functionality under water deficit is still poorly understood. In a dry-down experiment carried out on grapevines, at the peak of stress and when control vines zeroed whole-canopy net CO2 exchange rates/leaf area (NCER/LA), kaolin-treated vines maintained positive NCER/LA (~2 µmol m−2 s−1) and canopy transpiration (E) (0.57 µmol m−2 s−1). Kaolin-coated leaves had a higher violaxanthin (Vx) + antheraxanthin (Ax) + zeaxanthin (Zx) pool and a significantly lower neoxanthin (Nx) content (VAZ) when water deficit became severe. At the peak of water shortage, leaf ABA suddenly increased by 4-fold in control vines, whereas in kaolin-coated leaves the variation of ABA content was limited. Overall, kaolin prevented the biosynthesis of ABA by avoiding the deviation of the VAZ epoxidation/de-epoxidation cycle into the ABA precursor (i.e., Nx) biosynthetic direction. The preservation of the active VAZ cycle and transpiration led to an improved dissipation of exceeding electrons, explaining the higher resilience of canopy functionality expressed by canopies sprayed by kaolin. These results point out the interaction of kaolin with the regulation of the VAZ cycle and the active mechanism of stomatal conductance regulation.

Variable rate technologies allow site-specific management of parcels characterized by different levels of vigor and/or yield. N-fertilization based on actual plant needs is one of the most promising applications of precision farming aiming at improving efficiency, optimizing yield-to-quality relationship as well as limiting environmental impact. Although this strategy appears suitable for developing new viticultural models, few experiences validating this hypothesis are available in literature. Based on a pre-trial remotely sensed vigor map (NDVI-derived, 5 m resolution) a four-year study was performed in a Vitis vinifera L. 'Barbera' vineyard situated in the Colli Piacentini wine district. Vigor level (L = low, M = medium and H = high) and fertilization strategy (standard, variable rate application, and unfertilized control) were the main factors in a randomized block design. For each vigor level the study compared no N-supply (0 kg ha-1), standard supply (60 kg ha-1) and VRA supply delivering 0, 60 and 120 kg ha-1 to H, M and L, respectively. Post-trial effects were assessed by remote and proximal sensing considering a 5 m multispectral image and a very high resolution characterization of the canopy growth, respectively. Vine growth, yield, leaf nutritional status and fruit composition were assessed. Results show that variability among vigor levels was significantly reduced over year 3 and 4, whereas effects related to fertilization strategy were often non-significant. The canopy index calculated by proximal sensing proved that VRA was able to reduce variability among vigor levels (CV=1.42%) vs. standard fertilization at 60 kg ha-1 (8.20%). Leaf area did not vary among strategies while N-fertilization affected yield and vine balance. Despite VRA increased yield as compared to Standard, technological and phenolic maturity was similar in both fertilization strategies. The VRA reduced N waste in H while vines from L blocks showed a low sensitivity to increased N-supp

Land is variable and vine performances reflect such variability. Precision viticulture, based on remote sensing and variable rate technologies, is a valuable tool for its description and management. Because vineyard monitoring can be accomplished through different platforms, a wide array of solutions is now available combining different spatial and spectral resolutions, revisit time and cost. Challenge is selecting the most sensitive and cost-effective solution for facing specific technical issues. The research aims at comparing the sensitivity of four different remote and proximal sensing platforms in detecting within-field vigor variability of a 'Barbera' vineyard established in the Colli Piacentini wine district (NW of Italy). A panel of 8 vines was selected for each of three vigor classes (LV = low, MV = medium and HV = high) as previously identified by a 5 m resolution vigor map referred to July 2014. In 2016, physiological, agronomical and enological parameters were measured. Remote (satellite and UAV acquisitions at 10, 6 and 5 cm resolution) and proximal images (approximately one reading per vine) acquired in July 2016 were processed by calculating vigor indices and validated according to field data. Seasonal trend of Sentinel-2 derived NDVI values was described for each vigor class. Results show LV and HV vines always demonstrated different growth, yield and ripening patterns. This variability was successfully detected by satellite imagery and close correlations between Sentinel-2 and SPOT6-derived NDVI values with vegetative, yield and grape composition parameters were found. Canopy Index provided by proximal sensor MECS-VINE® was highly sensitive to vigor variation at the single plant scale. Open source Sentinel-2 allowed separating HV and LV areas over season suggesting potential suitability for vineyard monitoring and management under the experimental conditions. More consistent results require long-term confirmation.

A novel bud-forcing technique aimed at obtaining two crops (primary and forced) within the same season was tested on potted Pinot noir grapevines. Removing young, vegetative organs from primary shoots trimmed to six nodes in early summer allows dormant buds to break para-dormancy, leading to a delayed, second crop. Meanwhile, the primary crop is left untouched. In our study, bud-forcing was applied at three different timings (full flowering, fruit-set, groat-sized berries) and compared with an unforced control (UC). Vegetative growth, yield components, shoot and vine balance as leaf area-to-yield ratios, leaf gas exchange, and grape composition were determined. Regardless of the timing of application, forcing was effective at unlocking either apical or sub-apical dormant buds on the trimmed shoot, whereas the more basal nodes stayed dormant. The additional crop present on forced shoots was 40%–50% of primary crop, which equated to approximately 1 kg/vine for all treatments. Fruitfulness on newly formed forced shoots varied from 0.8 to 1.1 clusters/shoot. Primary clusters in vines subjected to forced treatments reached target maturity with a delay of 7–12 days compared to UC, whereas forced-crop, picked at the latest available date (October 7) showed higher total soluble solids, anthocyanins and phenolics than the primary crop while retaining higher acidity. This ripening behavior was reflected in the higher A rates measured in late season on the basal leaves of forced shoots versus those of primary shoots. Forcing did not compromise fruitfulness of the basal primary nodes, which set at about 1.2 inflorescence primordia/shoot. This is the first report supporting the feasibility of double cropping in Vitis vinifera L. in warm viticulture regions.

Global warming is endangering maintenance of optimal grape composition in white varietals aimed at sparkling wine making due to difficulties to maintain adequate acidity and fresh aromas. These troubles are being faced by the main white varietal of the Colli Piacentini district, named Ortrugo. Its vegetative and reproductive behavior was compared over 3 years with that of other minor autochthonous white varietals. Criteria set for adequate grape composition under sparkling vinification (total soluble solids at 20–21 Brix) and titratable acidity (TA)≥ 6.5 g/L combined with Principal Component Analysis (PCA) on the measured variables allowed a thinnning down of the initial group of 17 to 7 varietals including Ortrugo, Bucalò, Barbesino, Lecco, Melara, Santa Maria and Molinelli. PCA isolated Ortrugo’s behavior for inadequacy to maintain sufficient TA at harvest mostly due to extremely low malic acid concentration

Variable rate technologies allow site-specific management of parcels characterized by different levels of vigor and/or yield. Fertilization based on actual plant needs is one of the most promising applications of precision farming aiming at improving efficiency, optimizing vine balance, as well as limiting environmental impact. Although this strategy appears suitable for developing new vineyard management models, few experiences validating this hypothesis are available in the literature. Based on a pre-trial remotely sensed vigor map (NDVI-derived, 5 m resolution), a three-year study was performed in a Vitis vinifera L. cv. Barbera vineyard situated in the Colli Piacentini area. Vigor level (L = low, M = medium and H = high) and fertilization technique (Standard, Variable Rate Application, and unfertilized Control) were the main factors in a randomized block design. The controlled release fertilizer MulticoteTM Agri ([NPK fertilizer 13-5-21 + 7MgO+14SO3 (Controlled Release Nitrogen >46% on the total nitrogen, with longevity 2÷4 months), low in chloride] was used and the input rate calculated according to the N-supply. For each vigor level the study compared no fertilization (0 kg/ha), standard supply (40 kg of N /ha) and Variable Rate Application (VRA) supply delivering 0, 40 and 80 kg of N/ha to H, M and L, respectively. Vine growth, yield, leaf nutritional status and fruit composition were assessed. Results show that the classified L vigor plots had significantly less growth (i.e leaf area or pruning weight per vine) than M and H vigor plots, whereas yield components and grape composition followed a linear variation with vigor. There was a large prevalence of vigor x technique interactions suggesting that VRA had a differential impact on vine behavior depending upon the initial level of vigor. For vegetative and yield parameters, in the L vigor vines, increased MulticoteTM Agri dosage delivered as control (0 kg of N/ha), standard (40 kg of N/ha) and VRA (80 kg

Context and purpose of the study - Precision nutrient management in viticulture can be addressed on the basis of a spatial characterization of within-vineyard vine nutritional status derived from proximal or remote spectral observations. However, a key challenge is the discrimination between mineral deficiencies and water stress related issues, often coexisting under low vigor conditions. In addition several mineral disorders are associated to a decrease in chlorophyll concentration in leaves resulting in a wide array of symptoms classified as chlorosis. Despite clearly associated to their origin, visible symptoms appear too late for supporting an efficient mineral management; thus, non-destructive early detection of either asymptomatic excess or deficient status become a challenging task of precision viticulture. This work evaluates the Vis-NIR reflectance spectra and the sensitivity of the derived-spectral indices to detect nitrogen deficiency in grapevines. Material and methods - Well N-fertilized vs. unfertilized vines were compared over two seasons (2016 and 2017) on Vitis vinifera L. cv. Barbera potted vines. For each treatment, 24 leaves from eight representative vines were tagged in order to collect, at different phenological stages, contact Vis-NIR spectra and perform physiological measurements. The performance of several spectral vegetation indices sensitive to different biophysical (i.e. chlorophyll and carotenoids content, leaf area index) and physiological parameters (light use efficiency) was measured by means of a sensitivity (signal to noise ratio) analysis. Leaf greenness index was monitored with a handheld chlorophyll meter SPAD 502 whilst single-leaf gas exchanges were assessed by using a handheld analyzer. Multispectral analysis was associated to a rigorous ground-truthing as it concerns shoot growth, yield, fruit composition and pruning weight. Results – In both years the differential fertilization increased leaf N concentration of N+ vines at v

Several narrow or broadband spectral indices can be calculated at varying spatial and spectral resolution, which can then be correlated with the physiological and nutritional status of the leaves. In a three-year trial carried out on fruiting, potted cv. Barbera grapevines subjected to full (N+) or no (N0) nitrogen supply, seasonal evolution of different leaf spectral indices were correlated with non-destructive chlorophyll readings (Minolta SPAD meter), leaf gas exchange, and vine performance. Throughout the entire trial, N starvation resulted in greater-than-proportional limitation of vine yield as compared to vegetative growth (55% compared to 26% less than values measured on N+). Indices calculated within the red-edge spectral domain had highest sensitivity to relative change between N+ and N0, also indicating that the promptest response was recorded at the median shoot zone level. Twelve broadband indices were linearly correlated with leaf blade N concentration at veraison, indicating that N values ≤ 1.8% of dry matter identify a limiting N status. Any of these indices collected at the leaf level can be reliably used as a non-destructive predictor of N availability, albeit due to significant between-year variation in their absolute values at a given N level, readings should always include a well-supplied N treatment.

This paper follows a first contribution on the long-term effects of variable rate nitrogen application on vegetative growth and leaf nutritional status of a small Barbera vineyard, where three vigor levels classified as low, medium, and high (L, M, H) were identified pretrial from normalized difference vegetation index (NDVI) values determined by remotely sensed imagery (5 megapixel resolution). Variable rate fertilization supplying no N (0 kg/ ha; C), standard rate (60 kg/ha; S), and variable rate application (VRA) of 60 or 120 kg/ha to H, M, and L over four consecutive seasons showed that variability among vigor levels was significantly reduced in years three and four, while mean effects related to fertilization strategy were not significant. In this companion paper, L vines were most balanced, suggesting a change in fertilization strategy to no N application in M and H areas, and for maintenance supply in L plots. However, significant vigor level × year interactions indicated that within-vigor variability for total yield and berry weight was considerably reduced, while concomitant seasonal accumulations of sugar and color in 2014 and 2015 were much less variable within dates across vigor levels, suggesting the efficacy of the VRA approach. While the main effects of fertilization supply were mostly non-significant, seasonal accumulation of total soluble solids and anthocyanins in 2014 and 2015 showed that plots receiving 60 kg N/ha had lower within-date values than C (no N), suggesting increasing sensitivity over years. However, the L vines had an almost negligible response to increased N supply, and most observed responses were primarily due to reduced vine capacity.

In conclusione, l’utilizzo di biostimolanti a base dell’alga bruna Ascophyllum nodosum può essere una soluzione utile da adottare nei casi in cui le condizioni ambientali rappresentano un ostacolo per il raggiungimento di una adeguata maturazione fenolica. Tali composti sono infatti capaci di stimolare la biosintesi di antociani e polifenoli nelle bucce, senza modificare la concentrazione di zuccheri e acidi organici nelle uve, permettendo di ottenere vini con un miglior profilo cromatico e fenolico, a parità di titolo alcolico.

Il cambiamento climatico rende sempre più complicata la contemporaneità della maturazione tecnologica e fenolica. Una prova triennale dell’Università di Piacenza ha verificato l’efficacia della defogliazione alta in pre e post-invaiatura nel rallentare l’accumulo degli zuccheri nelle uve in un vitigno a bacca bianca a maturazione precoce

One of the most dangerous fungal diseases in viticulture is downy mildew. Copper-based active ingredients have been used for a long time to protect vines against Plasmopara viticola and they have always maintained an important role in the defense of vines especially for organic production. On the other hand, copper accumulates in the soil causing toxicity with negative consequences on plants and soil fauna. For this reason, new formulations with lower copper content have been considered. In recent years, foliar fertilizers have been studied, in particular those based on phosphites that, along with the nutritional function, stimulate the production of phytoalexins. Those metabolites cause the induced systemic resistance and act directly in the break of cell membranes of pathogens. This study aims to investigate the efficacy against downy mildew of a commercial product based on phosphites and of a new copper- based foliar fertilizer, where copper is chelated with gluconic acid and aminoacids of plant origin. Based on present results, phosphites significantly reduced the infection, without anyway achieving the defense effectiveness of the copper-based treatment however they ensure a significant reduction of the doses of copper necessary to achieve adequate levels of vineyard protection.

Variable rate application of vineyard inputs in field parcels characterized by different levels of vigor and/or yield is one of the most promising applications of precision agriculture. In a four-year study, we provided ground-truthing of three different vigor levels (L = low, M = medium, and H = high) derived pre-trial from Normalized Difference Vegetation Index (NDVI) values determined by remotely sensed imagery (5 m pixel resolution) in a small Barbera vineyard (0.64 ha). Each vigor level was subjected to three fertilization strategies (S) consisting of no N supply (C, 0 kg/ha), standard supply (S, 60 kg/ha), and variable-rate application (VRA) delivering 0, 60, and 120 kg/ha to H, M, and L vines, respectively. Post-trial effects were assessed by taking another NDVI satellite image at the same resolution and by adding proximal sensing performed with the MECS-VINE sensor yielding the estimation of a canopy index (CI). Ground-truthing was based on recording main vine growth parameters and leaf nutritional status. Results show that vine balance of L vines was optimal. Variability among vigor levels was significantly reduced in years 3 and 4, while mean effects related to fertilization strategy were not significant and very few S × V and S × Y interactions were found. However, when the ground-truthing assessment was compared with the CI index values, it was very clear that VRA was able to reduce variability among vigor levels (CV = 1.42%) versus standard fertilization at 60 kg/ha (8.20%).

Chitosan is a polysaccharide obtained by deacetylation of chitin, and it is involved in defence mechanisms of plants toward diseases. In the present work, V. vinifera L. cv. Ortrugo, grafted on 420A rootstock was grown in pot and treated, at veraison, by 0.03% chitosan solution at cluster level. Just before the treatment (T0) and 24 hours (T1), 48 hours (T2), 72 hours (T3) and 10 days (T4) later, the concentration of stilbenic compounds was detected, and at T1 proteomics and metabolomics analyses were done. Proteomics relies on the analysis of the complete set of proteins existing in a given substrate, while metabolomics relies on the analyses of the complete set of metabolites in a given substrate. The treatment improved the stilbene concentration over the control at T1. Proteomic analysis showed that superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL) were overexpressed in the treated grapes. SOD is known to be an enzyme active against reactive oxygen species (ROS) while PAL is a key enzyme in the phenylpropanoids pathway. Metabolomics analysis highlighted the positive role of the treatment in improving the triperpenoid concentration (betulin, erythrodiol, uvaol, oleanolate); these compounds are known to be effective against microbes, insects and fungi

L’annata vendemmiale 2017 verrà ricordata come piuttosto emblematica del cambiamento climatico che, sempre di più, condiziona rese e qualità delle uve nei vigneti italiani. In particolare, il 2017 lascia strascichi di episodi prolungati di stress idrico spesso associato a eccessi termici e, contemporaneamente, eventi di gelo tardivo (brinate) che, a macchia di leopardo, hanno colpito numerosi distretti viticoli causando danni ingenti che, in un buon numero di casi, sono corrisposti a un azzeramento pressoché totale della produzione.