Grapevine Vitis Vinifera Research Articles

Prevalence and pathogenicity of fungi associated with grapevine trunk diseases in Jordan

Grapevines (Vitis vinifera) are important fruit producers in Jordan, and grapevine trunk diseases (GTDs) are suspected to cause problems in many Jordanian vineyards. This study aimed to estimate GTDs incidence and severity in selected vineyards, and to isolate and identify the causal agents associated with GTDs in this country. Field surveys were carried out and representative samples of diseased vines showing GTDs symptoms were collected to isolate and identify the causal organisms. Molecular analyses of DNA sequences of the Internal Transcribed Spacer (ITS) regions of fungal ribosomal DNA (rDNA) were used to confirm the morphological identifications of the fungal isolates. GTDs were present in all the surveyed vineyards. Mean GTD incidence was 44% across all the fields evaluated, ranging from 9 to 69% in individual vineyards. Disease severity ranged from 52–74% (mean = 62%) across all vineyards and locations. A total of 325 fungal isolates were recovered from infected grapevines. The most prevalent pathogens identified were those associated with Botryosphaeria dieback, including Diplodia seriata, Lasiodiplodia theobromae and Neofusicoccum parvum, followed by the Esca disease pathogens Phaeoacremonium parasiticum, P. aleophilum, P. rubrigenum, and Fomitiporia spp. Ilyonectria liriodendri and I. spp., known to be associated with black foot of grapevines, were also isolated. Plant pathogens causing vascular wilts and root rots, including Fusarium proliferatum, F. oxysporum, Verticillium spp., and Rhizoctonia solani, were also identified from diseased plant samples, and were found in mixed infections with GTDs pathogens. Most of the identified pathogens, except those associated with vascular wilt and root rot, are reported for the first time in Jordan. Results of this study indicate that GTDs are widespread in Jordan, and that there is urgent need to adopt a “national strategy” for GTD management in this country.

Diverse spectra of virus infection identified through high throughput sequencing in nursery plants of two Indian grapevine cultivars

Grapevine (Vitis vinifera L.) is a valuable fruit crop known to be infected by more than 80 viruses and viroidal pathogens globally. In view of absence of indexing system for viruses and lack of information on viruses and viroids in grafted grapevine nursery plants in India, high throughput sequencing (HTS) based virome analysis of four libraries from sample pools and single plants from grafted nursery plants of two commonly grown grapevine cultivars namely Super Sonaka and Anushka was undertaken. RNA sequencing and analysis revealed the infection of 18 viruses and 5 viroids. Grapevine virus A and grapevine virus L (vitiviruses), grapevine leafroll-associated virus-3 (GLRaV-3) and GLRaV-4 (ampeloviruses) were the most predominant in all the grafted nursery plants based on the number of contigs, depth of coverage and copy number. Presence of grapevine virus D, grapevine virus H, and GLRaV-7 have been recorded for the first time in the Indian grapevine. Infection of these viruses obtained in HTS data was confirmed through RT-PCR and sequencing. Using de novo assembly and reference-based mapping, 43 complete or near complete genomes of the identified viruses and viroids were reconstructed from the sequenced grapevine samples. The phylogenetic analysis indicated the possible introduction of identified viruses through the import of infected planting materials which probably escaped quarantine procedure. The study showed the importance of HTS in detection of known and unknown viruses in plant propagules of clonally propagated perennial crops.

Foliar application of chitosan-putrescine nanoparticles (CTS-Put NPs) alleviates cadmium toxicity in grapevine (Vitis vinifera L.) cv. Sultana: modulation of antioxidant and photosynthetic status

BackgroundCadmium (Cd) stress displays critical damage to the plant growth and health. Uptake and accumulation of Cd in plant tissues cause detrimental effects on crop productivity and ultimately impose threats to human beings. For this reason, a quite number of attempts have been made to buffer the adverse effects or to reduce the uptake of Cd. Of those strategies, the application of functionalized nanoparticles has lately attracted increasing attention. Former reports clearly noted that putrescine (Put) displayed promising effects on alleviating different stress conditions like Cd and similarly chitosan (CTS), as well as its nano form, demonstrated parallel properties in this regard besides acting as a carrier for many loads with different applications in the agriculture industry. Herein, we, for the first time, assayed the potential effects of nano-conjugate form of Put and CTS (CTS-Put NP) on grapevine (Vitis vinifera L.) cv. Sultana suffering from Cd stress. We hypothesized that their nano conjugate combination (CTS-Put NPs) could potentially enhance Put proficiency, above all at lower doses under stress conditions via CTS as a carrier for Put. In this regard, Put (50 mg L− 1), CTS (0.5%), Put 50 mg L− 1 + CTS 0.5%” and CTS-Put NPs (0.1 and 0.5%) were applied on grapevines under Cd-stress conditions (0 and 10 mg kg− 1). The interactive effects of CTS-Put NP were investigated through a series of physiological and biochemical assays.ResultsThe findings of present study clearly revealed that CTS-Put NPs as optimal treatments alleviated adverse effects of Cd-stress condition by enhancing chlorophyll (chl) a, b, carotenoids, Fv/Fm, Y(II), proline, total phenolic compounds, anthocyanins, antioxidant enzymatic activities and decreasing Y (NO), leaf and root Cd content, EL, MDA and H2O2.ConclusionsIn conclusion, CTS-Put NPs could be applied as a stress protection treatment on plants under diverse heavy metal toxicity conditions to promote plant health, potentially highlighting new avenues for sustainable crop production in the agricultural sector under the threat of climate change.

Anthocyanin Accumulation and Its Corresponding Gene Expression, Total Phenol, Antioxidant Capacity, and Fruit Quality of ‘Crimson Seedless’ Grapevine (Vitis vinifera L.) in Response to Grafting and Pre-Harvest Applications

The color of grapevine berries is one of the most important quality parameters that define the appearance, attracts the consumer, and determines the price, especially in red grape cultivars. Some grape varieties show less color development due to many factors such as temperature, light intensity, and agricultural management. The present study aimed to evaluate diverse phytohormones coupled with grafting on quality and fruit coloration of ’Crimson Seedless‘ grapes. Pre-harvest foliar treatments of abscisic acid (ABA) at 400 mg L−1, methyl jasmonate (MeJ) at 1 mM L−1, ethephon (Eth) at 480 mg L−1, and melatonin (Mel) at 100 μmol were applied after 7 days and repeated after 21 days of ‘Veraison’ (beginning of the coloring phase). The results exposed that the ABA application provided the best anthocyanin accumulation with grafted grapevines whereas Eth displayed the maximum anthocyanin accumulation with ungrafted grapevines. Moreover, the expression of anthocyanin biosynthesis genes (chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), and flavanol 3-O-glucosyl transferase (UFGT)) was consistent with the anthocyanin concentration in berry peel. Moreover, Eth treatment revealed the highest total phenols and antioxidant capacity for both grafted and ungrafted grapevines. MeJ phytohormone exhibited the largest total yield, whereas the treatment of Eth increased the weight of 50 berries and the bunch. Furthermore, ABA induced the uppermost firmness and removal force. Regarding the chemical attributes, the Mel treatment revealed the minimum value of titratable acidity (TA) and the highest polyphenol oxidase (PPO) activity, while the MeJ treatment recorded the superior soluble solids content (SSC), in addition to phenylalanine ammonia-lyase (PAL) and catalase (CAT) enzymes activities. Eth treatment produced the highest activity of the peroxidase (POD) enzyme. Finally, the grafting treatment improved most of the studied fruit attributes.

Rapid leaf xylem acclimation diminishes the chances of embolism in grapevines.

Under most conditions tight stomatal regulation in grapevines (Vitis vinifera) avoids xylem embolism. The current study evaluated grapevine responses to challenging scenarios that might lead to leaf embolism and consequential leaf damage. We hypothesized that embolism would occur if the vines experienced low xylem water potential (Ψx) shortly after bud break or later in the season under a combination of extreme drought and heat. We subjected vines to two potentially dangerous environments: (i) withholding irrigation from a vineyard grown in a heatwave-prone environment, and (ii) subjecting potted vines to terminal drought 1 month after bud break. In the field experiment, a heatwave at the beginning of August resulted in leaf temperatures over 45 °C. However, effective stomatal response maintained the xylem water potential (Ψx) well above the embolism threshold, and no leaf desiccation was observed. In the pot experiment, leaves of well-watered vines in May were relatively vulnerable to embolism with 50% embolism (P50) at -1.8 MPa. However, when exposed to drought, these leaves acclimated their leaf P50 by 0.65 MPa in less than a week and before reaching embolism values. When dried to embolizing Ψx, the leaf damage proportion matched (percentage-wise) the leaf embolism level. Our findings indicate that embolism and leaf damage are usually avoided by the grapevines' efficient stomatal regulation and rapid acclimation of their xylem vulnerability.

Land Use Suitability Model for Grapevine (Vitis vinifera L.) Cultivation Using the Best Worst Method: A Case Study from Ankara/Türkiye

The product of grapes with the highest added value is wine. Wine grapes play an important role in the evaluation of barren lands, where no other plants generally grow. Viticulture in Türkiye is generally conducted on small areas of agricultural land. In order to develop viticulture, it is important to determine suitable areas. This study presents a model for assessing land suitability for cultivation of grapevines (Vitis vinifera L.) in the Ankara region (Türkiye). The aim is to provide a spatial decision support system based on geographic information system multi-criteria assessment, taking into account the perspectives of expert agricultural engineers and local product growers. In this study, 11 criteria were evaluated to determine the most suitable locations for grapevine cultivation. The best worst method was used to calculate the weights of the determined evaluation criteria. When the spatial distribution of the areas suitable for grapevine cultivation was examined from the resulting map produced, it was seen that 1879.29 km2 (7%) of highly suitability areas, 5062.03 km2 (20%) of medium suitability areas, 4706.20 km2 (18%) of low suitability areas, and 8355.36 km2 (33%) of unsuitable areas were detected. According to the results obtained, the southern parts of the study area are more suitable for grapevine cultivation. This study will be an important and useful regional guide for agricultural land use planning and the cultivation of grapevines.

GRAPEVINE CROWN GALL: CURRENT DATA AND RESEARCH PERSPECTIVES

Grapevine (Vitis vinifera L.) is one of the most widespread and economically important fruit crops in the world based on its capacity to produce high yields of quality fruit, hectares cultivated and its ability to grow in a wide range of climates and soils. However, it is greatly exposed to a wide variety of pathogens, affecting production and fruit quality. Among the potential threats, Allorhizobium vitis, the causal agent of grapevine crown gall represents a limiting factor in grape production worldwide. It causes vine decline and mortality especially in young vineyards and orchards with important economic losses. Owing of the systemic survival of Allorhizobium vitis in grapevine, copper bactericides and antibiotics are ineffective, and they are able to kill only the bacterium on contact. Therefore, the knowledge of pathogen, effective control and prevention strategies, and sensitive detection methods of pathogen are needed to improve the management of the disease. This review highlights the current state of research and the major acquisitions in this field and provides efficient procedures for isolating from tumors and soil. In addition, this paper discusses the different strategies used for the management of grapevine crown gall along with their drawbacks. Moreover, detection methods for rapid and proper identification of the disease bacteria were provided to enhance the efficiency of control measures and prevent the spread of the pathogen.

Arbuscular Mycorrhizal Fungi Enhance Drought Stress Tolerance by Regulating Osmotic Balance, the Antioxidant System, and the Expression of Drought-Responsive Genes in Vitis vinifera L.

Background and Aims. Drought harms the growth and productivity of grapevines; it thus poses a major threat to the development of viticulture in the background of ongoing climate change. Arbuscular mycorrhizal fungi (AMF) can be used to enhance the resistance/tolerance of plants to environmental stress. The effects of AMF on the osmotic regulation, antioxidant substances, and expression of drought-responsive genes in the grapevine Vitis vinifera L. cv. Ecolly were studied. Methods and Results. The experiment was conducted in a greenhouse in a completely randomized block design with four treatments: AMF colonization, well-watered; non-AMF colonization, well-watered; AMF colonization with drought stress; and non-AMF colonization with drought stress. The concentration of sucrose and proline in the leaves was higher in mycorrhizal grapevine than in nonmycorrhizal grapevine under drought stress. The concentration of malonaldehyde, hydrogen peroxide, superoxide anion, and glutathione and the activity of superoxide dismutase and peroxidase activity in leaves were higher in mycorrhizal grapevine than in nonmycorrhizal grapevine under drought conditions. AMF inoculation affected the expression of drought-responsive genes. Mycorrhization upregulated the expression of VvNCED, VvP5CS, VvSIP, VvPIP1;2, and VvTIP2;1 genes under drought stress. Conclusions. AMF could reduce the harm caused by drought stress by regulating osmosis, antioxidant activities, and the expression of key drought-responsive genes and aquaporin genes. Significance of the Study. This work provides insights into the physiological and biochemical activities influenced by AMF on grapevine under drought stress.

Effects of fungicide application on physiological and molecular responses of grapevine (Vitis vinifera L.): a comparison between copper and sulphur fungicides applied alone and in combination with novel fungicides.

Chemical products against fungi and oomycetes pose serious environmental issues. In the last decade, the use of less impacting active ingredients was encouraged to reduce chemical inputs in viticulture. In this study, the effect of different antifungal compounds on grapevine agronomic, physiological, and molecular responses in the vineyard was evaluated in addition to protection against powdery and downy mildews. In two years and in two Vitis vinifera cultivars (Nebbiolo and Arneis), a conventional crop protection approach, based on traditional fungicides (sulphur and copper), was compared to combined strategies. A well-known resistance inducer (potassium phosphonate), Bacillus pumilus strain QST 2808 and calcium oxide, both active ingredients whose biological interaction with grapevine is poorly characterized, were applied in the combined strategies in association with chemical fungicides. Despite a genotype effect occurred, all treatments optimally controlled powdery and downy mildews, with minimal variations in physiological and molecular responses. Gas exchange, chlorophyll content and photosystem II efficiency increased in treated plants at the end of season, along with a slight improvement in the agronomic performances, and an activation of molecular defence processes linked to stilbene and jasmonate pathways. The disease control strategies based on potassium phosphonate, Bacillus pumilus strain QST 2808 or calcium oxide combined with traditional chemical compounds did not cause severe limitations in plant ecophysiology, grape quality and productive yields. The combination of potassium phosphonate and calcium oxide with traditional fungicides can represent a valuable strategy for reducing copper and sulphur inputs in the vineyards, including those organically managed. This article is protected by copyright. All rights reserved.

An automated accelerated salting-out assisted solvent extraction (A-ASASE) of stilbenoids from Vitis vinifera L. branches: False proof or a proof of concept?

An automated accelerated salting-out assisted solvent extraction (A-ASASE) was developed. This approach made full use of the advantages of both the accelerated solvent extraction (ASE) technique and salting-out assisted liquid-liquid extraction (SALLE), without any modifications at the level of the ASE machine. The A-ASASE combined an automated extraction at high temperature/pressure and an enrichment step using eco-friendly solvents (e.g., water and ethanol) in a fully integrated and simple way that required only low volumes of solvents. The A-ASASE was successfully applied to extract three stilbenoids, namely E-resveratrol, E-ε-viniferin and E-vitisin B, present in grapevine (Vitis vinifera L.) by-products as a proof-of-concept compound. First, factors affecting the yield of stelbenoids by SALLE were investigated by means of a design of experiment model (DOE). The SALLE was then incorporated into ASE. Various ASE operational parameters such as temperature and number of cycles were also investigated. The highest yield was obtained using a mixture of ethanol-water, 70:30 (v/v) at 60 °C, using three extraction cycles and with 5 min of contact each. The highest yields of stilbenoids were 5.87 ± 0.28 g kg−1 dry weight, 3.27 ± 0.72 g kg−1 dry weight and 1.81 ± 0.2 g kg−1 dry weight for resveratrol, E-ϵ-viniferin and vitisin B, respectively. The A-ASASE was then successfully applied to extract the same stilbenoids from the roots of Vitis vinifera L. These results highlight the applicability of A-ASASE methodology to the extraction and enrichment of the extract in compounds of medium-high polarity in an easy and fully automated way.

Signaling Cross-Talk between Salicylic and Gentisic Acid in the 'Candidatus Phytoplasma Solani' Interaction with Sangiovese Vines.

"Bois noir" disease associated with 'Candidatus Phytoplasma solani' seriously compromises the production and survival of grapevines (Vitis vinifera L.) in Europe. Understanding the plant response to phytoplasmas should help to improve disease control strategies. Using a combined metabolomic and transcriptomic analysis, this work, therefore, investigated the phytoplasma-grapevine interaction in red cultivar Sangiovese in a vineyard over four seasonal growth stages (from late spring to late summer), comparing leaves from healthy and infected grapevines (symptomatic and symptomless). We found an accumulation of both conjugate and free salicylic acids (SAs) in the leaves of 'Ca. P. solani'-positive plants from early stages of infection, when plants are still asymptomatic. A strong accumulation of gentisic acid (GA) associated with symptoms progression was found for the first time. A detailed analysis of phenylpropanoids revealed a significant accumulation of hydroxycinnamic acids, flavonols, flavan 3-ols, and anthocyanin cyanidin 3-O-glucoside, which are extensively studied due to their involvement in the plant response to various pathogens. Metabolomic data corroborated by gene expression analysis indicated that phenylpropanoid biosynthetic and salicylic acid-responsive genes were upregulated in 'Ca. P. solani-positive plants compared to -negative ones during the observed period.

Variation in Susceptibility to Downy Mildew Infection in Spanish Minority Vine Varieties.

Downy mildew is one of the most destructive diseases affecting grapevines (Vitis vinifera L.). Caused by the oomycete Plasmopara viticola (Berk. and Curt.) Berl. and de Toni, it can appear anywhere where vines are cultivated. It is habitually controlled by the application of phytosanitary agents (copper-based or systemic) at different stages of the vine growth cycle. This, however, is costly, can lead to reduced yields, has a considerable environmental impact, and its overuse close to harvest can cause fermentation problems. All grapevines are susceptible to this disease, although the degree of susceptibility differs between varieties. Market demands and European legislation on viticulture and the use of phytosanitary agents (art. 14 of Directive 128/2009/EC) now make it important to know the sensitivity of all available varieties, including minority varieties. Such knowledge allows for a more appropriate use of phytosanitary agents, fosters the commercial use of these varieties and thus increases the offer of wines associated with different terroirs, and helps identify material for use in crop improvement programmes via crossing or genetic transformation, etc. Over 2020-2021, the susceptibility to P. viticola of 63 minority vine varieties from different regions of Spain was examined in the laboratory using the leaf disc technique. Some 87% of these varieties were highly susceptible and 11% moderately susceptible; just 2% showed low susceptibility. The least susceptible of all was the variety Morate (Madrid, IMIDRA). Those showing intermediate susceptibility included the varieties Sanguina (Castilla la Mancha, IVICAM), Planta Mula (Comunidad Valenciana, ITVE), Rayada Melonera (Madrid, IMIDRA), Zamarrica (Galicia, EVEGA), Cariñena Roja (Cataluña, INCAVI), Mandrègue (Aragón, DGA) and Bastardo Blanco (Extremadura, CICYTEX). The highly susceptible varieties could be differentiated into three subgroups depending on sporulation severity and density.

Rhizosphere-inhabiting fungi isolated from native plants of the atacama desert affect leaf traits of ‘chardonnay’ grapevines (Vitis vinifera L.).

Studying new alternatives for promoting plant growth is crucial to face a changing climate. This study aimed to determine the beneficial effect of fungal strains isolated from the rhizospheric soil of two native plants from the Atacama Desert on physiological leaf traits of inoculated ‘Chardonnay’ grapevines. Rhizosphere fungi were isolated from Baccharis scandens and Solanum chilense and tested in vitro for plant growth-promoting traits, including indole acetic acid, phosphate solubilization, siderophore production, and polyamine production. Aspergillus niger, Microdochium bolleyi, and Westerdikeya centenaria were isolated, showing plant growth-promoting attributes and high salt tolerance in almost all tested isolates. Then, the fungi were stabilized and co-inoculated in pot-grown ‘Chardonnay’ plants (Vitis vinifera L.) growing in outdoor conditions to evaluate gas exchange variables, chlorophylls (as SPAD value), water potential, proline and sugar content, and lipid peroxidation in leaves. Inoculation of the fungal strains significantly increased the photosynthesis rate, which was associated with higher mesophyll conductance and SPAD values. The co-inoculation also induced an enhanced protective condition for oxidative damage. Increased carbon assimilation resulted in higher soluble sugars and intrinsic water use efficiency in leaves without altering the water status of treated plants. Our results demonstrated the beneficial effects of co-inoculating rhizosphere-inhabiting fungi isolated from native plants from the Atacama Desert on physiological traits of ‘Chardonnay’ grapevines.

The Effects of Grapevine (Vitis vinifera L.) Leaf Extract on Growth Performance, Antioxidant Status, and Immunity of Zebrafish (Danio rerio)

An 8-week feeding trial was carried out to evaluate the effects of grapevine (Vitis vinifera) leaf extract (GLE) on the growth, oxidative enzymatic activities, immunity, and expression of antioxidant genes in zebrafish (Danio rerio). Three hundred and sixty zebrafish were supplied and fed with different levels of GLE: 0, 0.5, 1, and 2 g kg−1. The dietary administration of 1 g kg−1 of GLE significantly increased growth parameters in fish. Fish fed diets with GLE showed increased total protein. The total Ig and lysozyme activity significantly changed in the whole-body serum, but not in skin mucus. GLE significantly increased Catalase (CAT), Superoxide Dismutase (SOD), and Glutathione Peroxidase (GPx) activities compared to the control diet. GLE treatments caused a significant decrease in the malondialdehyde (MDA) content. In the skin mucus, only CAT and SOD activities significantly increased. The highest expression of Toll-like receptor-1 (TLR-1) and Tumor Necrosis Factor-α (TNFα) genes was achieved in fish fed 2 g kg−1 of GLE. CAT and SOD gene expressions were significantly higher in fish fed 1 and 2 g kg−1 of GLE. GPx gene expression was significantly higher in fish fed 1 g kg−1 of GLE. In conclusion, the results of the present study revealed that GLE affects growth performance and regulates antioxidant and immune gene expression. The determination of the optimum dosage merits further research.

Multigenic resistance to Xylella fastidiosa in wild grapes (Vitis sps.) and its implications within a changing climate

Xylella fastidiosa is a bacterium that infects crops like grapevines, coffee, almonds, citrus and olives. There is little understanding of the genes that contribute to plant resistance, the genomic architecture of resistance, and the potential role of climate in shaping resistance, in part because major crops like grapevines (Vitis vinifera) are not resistant to the bacterium. Here we study a wild grapevine species, V. arizonica, that segregates for resistance. Using genome-wide association, we identify candidate resistance genes. Resistance-associated kmers are shared with a sister species of V. arizonica but not with more distant species, suggesting that resistance evolved more than once. Finally, resistance is climate dependent, because individuals from low ( < 10 °C) temperature locations in the wettest quarter were typically susceptible to infection, likely reflecting a lack of pathogen pressure in colder climates. In fact, climate is as effective a predictor of resistance phenotypes as some genetic markers. We extend our climate observations to additional crops, predicting that increased pathogen pressure is more likely for grapevines and almonds than some other susceptible crops.

The Holocene history of grapevine (Vitis vinifera) and viticulture in France retraced from a large-scale archaeobotanical dataset

Grapevine and wine have deeply shaped the landscapes, economy and cultures of Europe and the Mediterranean. In France, it is considered that viticulture started in the south via contacts with Mediterranean populations (Greeks, Etruscans, Phoenicians), during the second half of the 1st millennium BCE, and spread further with the Romans. Wild grapevines were nevertheless present in various areas of the country all through the Holocene. No archaeological or historical source allows us to follow the history of grapevine and viticulture over the entire Holocene period and over the whole territory.In this paper we investigate the potential of archaeological plant macroremains (seed/fruits and wood) to trace the history of the vine on a large scale. We have assembled the largest possible database of published and unpublished archaeobotanical data, comprising 4449 site-phases for seed and fruits and 1356 site-phases for wood remains. In spite of taphonomic discrepancies and imbalances in the datasets, the different types of macroremains and modes of preservation produce consistent patterns. They provide the first comprehensive picture of the spread of grapevine, fluctuations in the economic role of viticulture and grape uses over time, although some periods and regions are less documented.Grapevine remains are regularly recorded from the Mesolithic to the Iron Age in most regions showing that human societies were already familiar with the wild plant and its fruits, especially in the Mediterranean. In this region, Vitis remains become considerably more frequent and numerous during the Iron Age, from around 500 BCE onwards, testifying to the rapid and strong implantation of viticulture. Grapevine macroremains confirm that the spread of viticulture outside the Mediterranean area occurred mainly during the Roman period. However, this expansion was limited and mainly focused on the South. The main expansion into the temperate zone took place during the Middle Ages. However, the more detailed fluctuations of viticulture, particularly in relation to climate oscillations are still difficult to follow. Pip remains are mainly associated with urban sites. This is a consequence of the actual consumption of grapes and may be evidence of a viticulture centered around urban areas.

Vitamin content and MDA levels of certain white grape varieties from different altitudes in Turkey

Grapevine (Vitis vinifera L.) is regarded as one of the world's most important fruit crops in terms of acreage and commercial worth. Grapes are used to make not only wine but also fresh fruit, dried fruit, and juice. The quality of grapes or wine is significantly affected by environmental factors such as altitude, soil type, and climate. In this study, the 5 white grape varieties (Ağın beyazı, Tahannebi, Kabarcık, Şilfoni, and Besni) grown at different altitudes (800 m, 1000 m and 1200 m) in Turkey were investigated for their vitamin, and phytosterol concentrations as well as lipid peroxidation content. Şilfoni grape harvested at 800 m was found to possess the lowest lipid peroxidation content. High altitudes, were found to reduce lipid peroxidation contents in the Ağın beyazı, Tahannebi, and Kabarcık strains. The highest stigmasterol (98.34 µg/g), and beta-sitosterol (86.90 µg/g) concentrations were found within Şilfoni grape variety harvested at 800 m. The highest vitamin D-2 and D-3 levels were found in Ağın beyazı (1.39 µg/g) and Kabarcık (4.13 µg/g) grape varieties, both harvested at 1200 m. Kabarcık grape, however, revealed the highest concentrations of R-tocopherol (63.09 µg/g) and alpha-tocopherol (24.13 µg/g) at 1200 m within the samples. The highest vitamin K-2 level was determined within the Tahannebi grape (15.44 µg/g) from 1200 m. It was observed that the vitamin and phytosterol concentrations of white grape varieties tended to increase, while the lipid peroxidation values tended to decrease at high altitudes, especially at 1200 m. This study also exhibited a strong relationship among Vitamin D3, R-tocopherol, and alpha-tocopherol in the studied white grape cultivars. Keywords: Vitis vinifera; White grape; Vitamin; MDA; Altitude

A Tunisian wild grape leads to metabolic fingerprints of salt tolerance.

Soil salinity is progressively impacting agriculture, including viticulture. Identification of genetic factors rendering grapevine (Vitis vinifera L.) resilience that can be introgressed into commercial varieties is necessary for safeguarding viticulture against the consequences of global climate change. To gain insight into the physiological and metabolic responses enabling salt tolerance, we compared a salt-tolerant accession of Vitis sylvestris from Tunisia, "Tebaba", with "1103 Paulsen" rootstock widely used in the Mediterranean. Salt stress was slowly increased, simulating the situation of an irrigated vineyard. We determined that "Tebaba" does not sequester sodium in the root but can cope with salinity through robust redox homeostasis. This is linked with rechanneling of metabolic pathways toward antioxidants and compatible osmolytes, buffering photosynthesis, such that cell-wall breakdown can be avoided. We propose that salt tolerance of this wild grapevine cannot be attributed to a single genetic factor but emerges from favorable metabolic fluxes that are mutually supportive. We suggest that introgression of "Tebaba" into commercial varieties is preferred over the use of "Tebaba" as a rootstock for improving salt tolerance in grapevine.

Heritage grapevines as sources of biological control agents for Botryosphaeria dieback pathogens

Grapevine trunk diseases cause severe damage in grapevines. Management strategies focus on protection of grapevine pruning wounds using chemical fungicides or biological control agents. Botryosphaeria dieback, caused mainly by Lasiodiplodia spp., is one of the main trunk diseases in northwest Mexico. This study obtained endophytic bacteria and fungi from the heritage grapevine Vitis vinifera cv. ‘Mission’ for potential biological control of Botryosphaeria dieback. A collection of 135 bacterial and 37 fungal isolates were obtained and initially tested for antagonistic activity against Lasiodiplodia brasiliensis. The most promising isolates belonging to Trichoderma and Bacillus spp. were selected and characterized to determine their modes of action. Bacillus isolates produced volatile organic compounds that inhibited growth of Neofusicoccum parvum, and diffusible organic compounds with antifungal effects against L. brasiliensis and N. parvum. Trichoderma isolates produced diffusible organic compounds and were mycoparasites. In greenhouse assays, plants inoculated with three Trichoderma asperellum isolates (T20BCMX, EF09BCMX, and EF11BCMX), B. amyloliquefaciens (BEVP26BCMX) or Bacillus sp. (rbES015), applied preventively in soil, gave up to 50% smaller necrotic lesions when compared with the plants inoculated only with L. brasiliensis. In the field, plants inoculated with three Bacillus isolates (BEVP02BCMX, BEVP26BCMX, BEVP31BCMX) or five Trichoderma (T11BCMX, T15BCMX, T17BCMX, T20BCMX, and EF11BCMX) had lesions up to four times smaller than control plants inoculated only with L. brasiliensis. This study has demonstrated the potential of heritage grapevines to provide biological control agents for Botryosphaeria dieback.

Exploring genetic diversity and population structure of a large grapevine (Vitis vinifera L.) germplasm collection in Türkiye.

Grapevine (Vitis Vinifera L.) has been one of the significant perennial crops in widespread temperate climate regions since its domestication around 6000 years ago. Grapevine and its products, particularly wine, table grapes, and raisins, have significant economic importance not only in grapevine-growing countries but also worldwide. Grapevine cultivation in Türkiye dates back to ancient times, and Anatolia is considered one of the main grapevine migration routes around the Mediterranean basin. Turkish germplasm collection, conserved at the Turkish Viticulture Research Institutes, includes cultivars and wild relatives mainly collected in Türkiye, breeding lines, rootstock varieties, and mutants, but also cultivars of international origin. Genotyping with high-throughput markers enables the investigation of genetic diversity, population structure, and linkage disequilibrium, which are crucial for applying genomic-assisted breeding. Here, we present the results of a high-throughput genotyping-by-sequencing (GBS) study of 341 genotypes from grapevine germplasm collection at Manisa Viticulture Research Institute. A total of 272,962 high-quality single nucleotide polymorphisms (SNP) markers on the nineteen chromosomes were identified using genotyping-by-sequencing (GBS) technology. The high-density coverage of SNPs resulted in an average of 14,366 markers per chromosome, an average polymorphism information content (PIC) value of 0.23 and an expected heterozygosity (He) value of 0.28 indicating the genetic diversity within 341 genotypes. LD decayed very fast when r2 was between 0.45 and 0.2 and became flat when r2 was 0.05. The average LD decay for the entire genome was 30 kb when r2=0.2. The PCA and structure analysis did not distinguish the grapevine genotypes based on different origins, highlighting the occurrence of gene flow and a high amount of admixture. Analysis of molecular variance (AMOVA) results indicated a high level of genetic differentiation within populations, while variation among populations was extremely low. This study provides comprehensive information on the genetic diversity and population structure of Turkish grapevine genotypes.