Search Results (142)

The present study was undertaken for six years to appraise the responses of four-year-old established grapevines (Vitis vinifera L., cv. Perlette) to saline–sodic groundwater irrigation in relation to different amendments in a field experiment on non-saline, non-sodic calcareous sandy loam soil under a semi-arid climate at the research farm of Punjab Agricultural University, Regional Research Station, Bathinda, Punjab, India. Different water quality treatments, viz., canal water or good-quality water (GQW), poor-quality saline–sodic groundwater (PQW), alternate irrigation of canal water and groundwater (GQW/PQW), PQW with 50% gypsum (CaSO₄·2H₂O) requirement (PQW + GR₅₀), PQW with 100% gypsum requirement (PQW + GR₁₀₀), and PQW with sulphitation pressmud (by-product of sugar industry) @ 6.6 t ha⁻¹ on a dry weight basis (PQW + SPM), applied in furrows, were imposed in quadruplicate with a randomized block design. PQW with an electrical conductivity (EC) of 2.2–2.4 dS m⁻¹, residual sodium carbonate (RSC) content of 6.21–6.44 mmolc L⁻¹, and a sodium adsorption ratio (SAR) from 23.1 to 24.8 (mmolc L⁻¹)^0.5 was used during the course of experimentation. The pooled mean 6-year data showcased that the treatments GQW/PQW, PQW + GR₅₀, PQW + GR₁₀₀, and PQW + SPM improved the berry yield by 28.3%, 11.3%, 21.2%, and 31.0%, respectively, when compared with PQW. Use of amendments, i.e., gypsum, sulphitation pressmud, and practice of GQW/PQW for irrigation in a cyclic mode, helped in reducing the pH, SAR, and bulk density (BD) of surface soil (0–15 cm) and enhancing the final infiltration rate (FIR) of soil and berry yield. A maximum water use efficiency (WUE) of 3.99 q ha⁻¹-cm was recorded in the GQW treatment, followed by 3.93, 3.72, and 3.68 q ha⁻¹-cm in the PQW + SPM, GQW/PQW, and PQW + GR₁₀₀ treatments, respectively. Application of amendments alongside PQW evidenced a significant enhancement in total soluble solids (TSSs) and a decrease in the acidity of berries as compared to PQW. These results suggest that table grape yield (cv. Perlette) on calcareous sandy loam soil under saline–sodic groundwater irrigation can be sustained with the application of PQW + GR₁₀₀, sulphitation pressmud, and GQW/PQW in already-established grapevines with minimal detrimental effects on soil health. Full article

Grapevine (Vitis vinifera L.) cultivation is an important agricultural sector worldwide. Its expansion into new areas, like Kazakhstan, brings significant phytosanitary risks. Viroids, such as grapevine yellow speckle viroid 1 (GYSVd-1) and hop stunt viroid (HSVd), are RNA pathogens that threaten vineyard productivity. They can cause a progressive decline through latent infections. Traditional diagnostic methods are usually targeted and therefore not suitable for thorough surveillance. In contrast, modern high-throughput sequencing (HTS) methods often face challenges due to their high costs and complicated sample preparation, such as ribosomal RNA (rRNA) depletion. This study introduces a simplified diagnostic workflow that overcomes these barriers. We utilized the latest Oxford Nanopore V14 cDNA chemistry, which is designed to prevent internal priming, by substituting a targeted oligo(dT)VN priming strategy to facilitate the sequencing of non-polyadenylated viroids from total RNA extracts, completely bypassing the rRNA depletion step and use of random oligonucleotides for c DNA synthesis. This method effectively detects and identifies both GYSVd-1 and HSVd. This workflow significantly reduces the time, cost, and complexity of HTS-based diagnostics. It provides a powerful and scalable tool for establishing strong genomic surveillance and phytosanitary certification programs, which are essential for supporting the growing viticulture industry in Kazakhstan. Full article

Color, aroma, and overall sensory quality in red wines are largely influenced by oxygen availability during fermentation. This study evaluated the effects of micro-oxygenation under hyperbaric conditions on the physicochemical, chromatic, volatile, and sensory properties of Vitis vinifera L. cv. Monastrell grape must. Grape clusters were manually harvested and fermented under controlled conditions, applying micro-oxygenation treatments at two fermentation stages (day 3 and day 13) within a hyperbaric chamber. Physicochemical analyses, CIELab color measurements, visible reflectance spectra, GC-FID volatile profiling, and descriptive sensory analysis were performed. Micro-oxygenated samples (M1_MOX and M2_MOX) showed significant increases in lightness (L*), redness (a*), chroma (C*), and reflectance in the 520–620 nm range, indicating enhanced extraction and stabilization of phenolic pigments. Volatile analysis revealed that these samples also contained higher concentrations of key esters and terpenes associated with fruity and floral notes. Sensory evaluation confirmed these findings, with MOX-treated wines displaying greater aromatic intensity, flavor persistence, and varietal character. Control samples (M1_CON and M2_CON) exhibited lower color saturation and volatile compound content, along with diminished sensory quality. These results suggest that hyperbaric micro-oxygenation is an effective strategy for improving color intensity and aromatic complexity during red wine fermentation under controlled, non-thermal conditions. Full article

The commercial production of grapevines (Vitis vinifera L.) relies heavily on rootstocks that are hybrids of non-vinifera parentage. The relatively newly released GRN rootstocks (GRN-1, GRN-2, GRN-3, GRN-4, and GRN-5) were bred from especially under-studied genetic backgrounds. This study aimed to evaluate ungrafted GRN-series grape rootstocks under moderate water-stress conditions and to characterize and compare their physiological performances. Each of the GRN rootstocks had specific physiological characteristics that would make them suitable for a wide range of growing conditions and vineyard management goals. GRN-1 had growth habits which were more vigorous and the highest carbohydrate storage levels, while GRN-2 had the highest level of nitrogen and the largest leaf area, but the lowest levels of carbohydrate storage. GRN-3 was less tolerant to high-salinity soils, and had the longest internodes, while GRN-4 had high boron levels, which supports flowering and fruit set, and short internodes. GRN-5 was consistently moderate across all measured areas, except internode thickness, for which it was the highest. These findings show the variations in physiological growth habits among the ungrafted GRN-series rootstocks and suggest that growth habits, carbohydrate storage, leaf canopy, fruit production, and nutrition vary based on rootstock parentage. Further investigation is needed to determine whether these characteristics persist when grafted onto Vitis vinifera L. scions. Full article

The production of winter wines in Southeastern Brazil represents a relatively recent but expanding viticultural approach, with increasing adoption across diverse wine-growing regions. This system relies on the double-pruning technique, which allows for the harvest of grapes during the dry and cooler winter season, favoring a greater accumulation of sugars, acids, and phenolic compounds. This study aimed to characterize the phenological stages, thermal requirements, yield, and fruit quality of the fine wine grape cultivars ‘Sauvignon Blanc’, ‘Merlot’, ‘Tannat’, ‘Pinot Noir’, ‘Malbec’, and ‘Cabernet Sauvignon’ under double-pruning management in a subtropical climate. The vineyard was established in 2020, and two production cycles were evaluated (2022/2023 and 2023/2024). Significant differences in the duration of phenological stages were observed among cultivars, ranging from 146 to 172 days from pruning to harvest. The accumulated thermal demand was higher in the first cycle, with a mean of 1476.9 growing degree days (GDD) across cultivars. The results demonstrate the potential of Vitis vinifera L. cultivars managed with double pruning for high-quality wine production under subtropical conditions, supporting the viability of expanding viticulture in the state of São Paulo. ‘Cabernet Sauvignon’ and ‘Sauvignon Blanc’ showed the highest yields, reaching 3.03 and 2.75 kg per plant, respectively, with productivity values of up to 10.8 t ha⁻¹. ‘Tannat’ stood out for its high sugar accumulation (23.4 °Brix), while ‘Merlot’ exhibited the highest phenolic (234.9 mg 100 g⁻¹) and flavonoid (15.3 mg 100 g⁻¹) contents. These results highlight the enological potential of the evaluated cultivars and confirm the efficiency of the double-pruning system in improving grape composition and wine quality in non-traditional viticultural regions. Full article

The Demarcated Region of Madeira (DRM) is one of the oldest wine regions in Portugal, where the famous Madeira Wine (MW) is produced by spontaneous fermentation using endogenous yeasts. Several studies reported the role of endogenous Saccharomyces cerevisiae strains in the regional identity of wines, but only a few studies have been published in the DRM. The PCR-Interdelta (Polymerase Chain Reaction-Interdelta) analysis is a reliable method for S. cerevisiae strain identification. Here, we report the S. cerevisiae strains isolated from six Vitis vinifera grape varieties, namely, Tinta Negra, Boal, Sercial, Verdelho, Malvasia de São Jorge, and Complexa, which are widely used in MW production. During the 2020 campaign, eleven samples were collected from licensed vineyards and a winery, and submitted to spontaneous microfermentations and yeast isolation. Of the 1452 isolates counted, 1367 (94.2%) presented morphological characteristics of S. cerevisiae. We randomly selected 330 isolates from the positive colonies for strain identification. First, the PCR-Interdelta was optimized in ten commercial strains, using δ2–δ12 and δ12–δ21 pairs of primers, and δ2–δ12 primers were selected to screen the 330 isolates. We detected three fermentative profiles and a total of 25 PCR-Interdelta patterns were obtained, representing 7.6% of intraspecific variability, starting with the first non-official collection. The findings underscore the pivotal role of S. cerevisiae strain diversity in shaping the regional identity and quality of wines, with molecular tools like PCR-Interdelta analysis proving essential for monitoring intraspecific variability. Full article

Semi-arid viticultural regions globally are experiencing severe and frequent growing-season heat waves that negatively impact grapevine (Vitis vinifera L.) physiological performance and productivity. At the leaf level, heat stress can photodamage both Photosystem I (PSI) and Photosystem II (PSII). In order to study the self-protection mechanism of grapevine leaves, in this study, 3-year-old potted ‘Merlot’ and ‘Muscat Hamburg’ grapevines were exposed to a 5-day simulated heatwave (45/25 °C day/night) and compared to vines maintained at 25/18 °C. After heat exposure, ‘Merlot’ demonstrated superior thermotolerance and superior physiological performance as measured by gas exchange, oxidative parameters, chlorophyll loss, and photoinhibition of PSI and PSII. Additionally, non-photochemical quenching (NPQ) dissipated the excess light energy in the form of heat. Y(NPQ) progressively rose from 0 to 0.6, signaling the start of the grapevine leaves’ self-defense against temperature stress. Furthermore, the stimulation of cyclic electron flow (CEF) under high temperatures contributed to the energy balance of PSI. The CEF of ‘Muscat Hamburg’ under high light intensities increased dramatically from 1 to 4. NAD(P)H dehydrogenase-dependent CEF around PSI increased markedly, suggesting its role in self-protection. These results demonstrate that both NPQ and CEF play key photoprotective roles by generating a proton gradient under heat stress. Full article

High temperatures significantly impact grapevine growth and development and lead to severe losses in grape quality and production. To minimize the impact of those environmental constraints, the application of biostimulants (BSts) has emerged as one of the most interesting strategies. BSts application derived from cactus species has been described as a successful approach to enhance tolerance to biotic and abiotic stresses. In this study, an aqueous extract prepared from the cladodes of Opuntia ficus-indica was applied through foliar spraying to grapevine plants (Vitis vinifera L.) ’Aragonez’ already under heat stress. The effect of the extract application on protecting grapevine plants against heat stress was assessed in an experiment running during 15 days after extract application by determining several physiological parameters and detecting the changes in the whole proteome profile by comparing non-treated and extract-treated samples. Results show that physiological parameters directly related to photosynthesis showed a positive effect of the extract in mitigating heat stress in grapevines. Proteomic analysis indicated that the extract significantly upregulated proteins associated with photosynthesis and stress responses. This study provides new insights about the effect of O. ficus-indica extract in grapevines, offering a valuable strategy for future applications under field conditions. Full article

Red wines produced with interspecific grape cultivars tend to have low tannin concentration and are therefore unbalanced. Extended maceration (EM) is a common winemaking technique which can promote the extraction of tannins from grape skins and seeds. The goal of this study was to evaluate the effect of EM on the tannin concentration, color intensity and other chemical properties of red wines made from cold-hardy grape cultivars. The wines were made from two cold-hardy interspecific grape cultivars (Marquette, and Petite Pearl) for either 7 days (control) or 21 days (EM) before pressing. Chemical analysis of the wines was conducted to determine their tannin concentration and color parameters at different stages of the process and after 14 months of aging. EM resulted in an improvement in the iron-reactive phenolic content of Marquette red wines (from 582 to 969 mg/L at bottling in control and EM wines, respectively), but no significant improvement in tannin content. The hue of Petite Pearl wines increased following EM only at pressing, and color intensity of those wines decreased at pressing and bottling by 43% and 52%, respectively. This study was the first one conducted on non-Vitis vinifera grapes which showed a lack of impact of EM on the phenolics and tannin concentration in the red wines made in 2022. Full article

Background: Hydrophilic compounds, such as amino acids, organic acids and sugars, among others, are present in large amounts in plant cells. The analysis and quantification of these major hydrophilic compounds are particularly relevant in plant science because they have a considerable impact on the quality of plant-derived products and on plant–pathogen relationships. Our objective was to develop and validate a complete analysis workflow combining a water-based extraction procedure with a fast separation using hydrophilic interaction liquid chromatography coupled to high-resolution mass spectrometry (HILIC-HRMS) for quantitative analysis of hydrophilic compounds in plant tissues. Results: Water-based microwave-assisted extraction (MAE) methods for hydrophilic compounds were compared using HILIC-HRMS. The newly developed method involved 20 s MAE time followed by a 10 min HILIC-HRMS analysis. This bioanalytical method was validated for 24 polar metabolites, including amino acids, organic acids, and sugars, to ensure the reliability of analytical results: selectivity, limits of detection and quantification, calibration range and precision. Depending on the compounds, quantification limit was as low as 0.10 µM up to 4.50 µM. Between-run RSDs evaluated on Vitis vinifera and Arabidopsis samples were all below 20% except for three compounds. Conclusions: A water-based MAE method, coupled with HILIC-HRMS, was developed for the absolute quantification of free amino acids, organic acids, and sugars in plant tissues. Its effectiveness was demonstrated in both lignified plants, such as Vitis vinifera, and non-lignified plants, such as Arabidopsis. This method is suitable for medium- to high-throughput analysis of key polar metabolites from small amounts of plant material. Full article

Extracting high-quality RNA from grape (Vitis Vinifera) berry skins is challenging due to their high levels of polysaccharides, phenolic compounds, sugars, and organic acids, which can negatively impact RNA purity and yield. Indeed, polyphenols can bind to RNA, polysaccharides may co-precipitate, and sugars and organic acids can interfere with the pH and ionic properties of the extraction buffer. Commercial kits offer a quick extraction method but are often ineffective for grape berry skins. Similarly, protocols that work well for other vegetal tissues are also inefficient and time-consuming for this tissue. To overcome these limitations, we optimized the RNA isolation by adding a sorbitol pre-wash step to both a non-commercial protocol and a commercial kit. Our results show that it significantly improves the RNA yield and quality from grape berry skins, increasing the RNA purity and integrity, as evidenced by higher RIN (RNA Integrity Number) values and better Qubit and Nanodrop measurements. The strategy’s efficacy was further validated through RNA sequencing, yielding high-quality reads with low error rates, suitable for gene expression studies. Thus, incorporating a sorbitol pre-wash step improves the RNA yield and quality from grape berry skins making it suitable for high-throughput sequencing, and provides a reliable tool for advancing grapevine research. Full article

Maratheftiko (Vitis vinifera sp.) is a prestigious grape variety native to Cyprus, but wines originating from this variety have not been examined with respect to the effect of aging on major quality determinants, such as their aromatic and polyphenolic composition. Following a previous work on the impact of prefermentation treatments on Maratheftiko wines, this work was carried out with the objective of studying the effect of barrel aging on Maratheftiko wines, produced on industrial scale with different prefermentation technologies. These technologies includes combinations of the saigneé process, cold maceration, and enzyme and tannin addition. The influence of these treatments was illustrated by determining the pigment, non-pigment polyphenols, and volatiles from two consecutive harvests. The predominant non-pigment polyphenol for the 2021 vintage was quercetin 3-O-glucuronide, accompanied by a ferulate derivative, but for the 2022 vintage, quercetin 3-O-glucuronide predominated along with caftaric acid. The principal anthocyanin in all samples examined was malvidin 3-O-glucoside, followed by its p-coumarate derivative. The primary aromatic substances determined were isoamyl alcohol, followed by 2-phenylethanol. Principal component analysis showed that there was discrimination based on prefermentation treatments; however, distinction was more pronounced based on vintage. This investigation provided heretofore unreported data and revealed novel insights into the effect of aging on Maratheftiko wines. Full article

Repeated expeditions across various regions of Georgia in the early 2000s led to the identification of 434 wild grapevine individuals (Vitis vinifera L. subsp. sylvestris (C.C. Gmel.) Hegi) across 127 different sites, with 45% of these sites containing only a single vine and only 7% more than 9 vines. A total of 70 accessions were propagated in a germplasm collection, 41 of them were descripted from the ampelographic point of view and 32 from the phenological one. The geographical and ecological analysis confirmed that wild grapevines primarily grow in humid environments with warm and fully humid climates, often near rivers. They favor deep, fertile, and evolved soils, mainly alluvial and cinnamonic types (80%), with a marginal presence on strongly eroded soils. Their main natural vegetations are forests and open woodlands, with some individuals in the Southeast found in steppes. The altitudinal range spans from 0 to 1200 m, with 80% of vines distributed between 400 and 900 m. The phenological analysis revealed significant differences among the accessions but no difference among populations, with only a slight variation in bud-break timing, indicating a high level of synchronicity overall. Flowering timing proved to be the most uniform stage, suggesting minimal environmental pressure on genetic adaptation. The mature leaf morphology exhibited significant polymorphism, though leaves were generally three- or five-lobed, weak-wrinkling, and -blistering, with a low density of hairs. Bunch and berry morphology were more uniform. Bunches were consistently very small, cylindrical, and never dense or winged. Berries were also very small, mostly globular, always blue-black in color, and non-aromatic. A striking feature was the frequency of red flesh coloration, which ranged from weak to strong, with uncolored flesh being rare. The Georgian population of wild grapevines was found to be fragmented, often consisting of scattered single individuals or small groups. Therefore, we believe it is urgent for Georgia to implement specific protection measures to preserve this vital genetic resource. Full article

Grapevine red blotch is an emerging disease that threatens vineyard productions in North America. Grapevine red blotch virus (GRBV, species Grablovirus vitis, genus Grablovirus, family Geminiviridae), the causal agent of red blotch disease, is transmitted by Spissistilus festinus (Hemiptera: Membracidae) in a circulative, non-propagative mode. To gain new insight into GRBV-S. festinus interactions, we delved into vertical transmission and documented a lack of transovarial transmission. In addition, we investigated S. festinus sex differences in the horizontal transmission of GRBV by creating small arenas with 30 detached trifoliates of common snap bean, an experimental host of GRBV, and a preferred feeding host of S. festinus. Tracking the movement of viruliferous males, females, or a combination of the two sexes over two weeks in replicated experiments demonstrated that male S. festinus dispersed more than females with specimens of both sexes predominantly grouping together on trifoliates spatially surrounding the trifoliate onto which they were released. These behaviors resulted in a greater rate of GRBV transmission by S. festinus males (17%, 20 of 120) than females (4%, 5 of 120) or mixed-sex cohorts (9%, 17 of 180). In arenas with aviruliferous S. festinus and one (single) or four (hotspot) GRBV-infected trifoliates out of 30 total trifoliates, a higher GRBV transmission rate by males was confirmed in both single infection (50%, 30 of 60) and hotspot infection (83%, 50 of 60) arenas than by females in single infection (35%, 21 of 60) and hotspot infection (67%, 40 of 60) arenas. These findings highlighted sex-associated differences in the transmission of GRBV by S. festinus and a positive correlation between the initial virus prevalence and the rate of transmission. Finally, the secondary spread of GRBV resulted primarily from S. festinus dispersal by walking or jumping. Together, these unique GRBV transmission features support the need to characterize dispersal behaviors of S. festinus in vineyard ecosystems. Full article

Plant cation–chloride cotransporters (CCCs) are proposed to be Na⁺-K⁺-2Cl⁻ transporting membrane proteins, although evolutionarily, they associate more closely with K⁺-Cl⁻ cotransporters (KCCs). Here, we investigated grapevine (Vitis vinifera L.) VvCCC using 3D protein modeling, bioinformatics, and electrophysiology with a heterologously expressed protein. The 3D protein modeling revealed that the signatures of ion binding sites in plant CCCs resembled those of animal KCCs, which was supported by phylogenomic analyses and ancestral sequence reconstruction. The conserved features of plant CCCs and animal KCCs included predicted K⁺ and Cl⁻-binding sites and the absence of a Na⁺-binding site. Measurements with VvCCC-injected Xenopus laevis oocytes with VvCCC localizing to plasma membranes indicated that the oocytes had depleted intracellular Cl⁻ and net ⁸⁶Rb fluxes, which agreed with thermodynamic predictions for KCC cotransport. The ⁸⁶Rb uptake by VvCCC-injected oocytes was Cl⁻-dependent, did not require external Na⁺, and was partially inhibited by the non-specific CCC-blocker bumetanide, implying that these properties are typical of KCC transporters. A loop diuretic-insensitive Na⁺ conductance in VvCCC-injected oocytes may account for earlier observations of Na⁺ uptake by plant CCC proteins expressed in oocytes. Our data suggest plant CCC membrane proteins are likely to function as K⁺-Cl⁻ cotransporters, which opens the avenues to define their biophysical properties and roles in plant physiology. Full article