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We elucidate grapevine evolution and domestication histories with 3525 cultivated and wild accessions worldwide. In the Pleistocene, harsh climate drove the separation of wild grape ecotypes caused by continuous habitat fragmentation. Then, domestication occurred concurrently about 11,000 years ago in Western Asia and the Caucasus to yield table and wine grapevines. The Western Asia domesticates dispersed into Europe with early farmers, introgressed with ancient wild western ecotypes, and subsequently diversified along human migration trails into muscat and unique western wine grape ancestries by the late Neolithic. Analyses of domestication traits also reveal new insights into selection for berry palatability, hermaphroditism, muscat flavor, and berry skin color. These data demonstrate the role of the grapevines in the early inception of agriculture across Eurasia.

Background and Aims Condensed tannins, responsible for berry and wine astringency, may have been selected during grapevine domestication. This work examines the phylogenetic distribution of condensed tannins throughout the Vitaceae phylogenetic tree. Methods Green berries and mature leaves of representative true-to-type members of the Vitaceae were collected before ‘véraison’, freeze-dried and pulverized, and condensed tannins were measured following depolymerization by nucleophilic addition of 2-mercaptoethanol to the C4 of the flavan-3-ol units in an organic acidic medium. Reaction products were separated and quantified by ultrahigh pressure liquid chromatography/diode array detection/mass spectrometry. Key Results and Conclusions The original ability to incorporate epigallocatechin (EGC) into grapevine condensed tannins was lost independently in both the American and Eurasian/Asian branches of the Vitaceae, with exceptional cases of reversion to the ancestral EGC phenotype. This is particularly true in the genus Vitis, where we now find two radically distinct groups differing with respect to EGC content. While Vitis species from Asia are void of EGC, 50 % of the New World Vitis harbour EGC. Interestingly, the presence of EGC is tightly coupled with the degree of leaf margin serration. Noticeably, the rare Asian EGC-forming species are phylogenetically close to Vitis vinifera, the only remnant representative of Vitis in Eurasia. Both the wild ancestral V. vinifera subsp. sylvestris as well as the domesticated V. vinifera subsp. sativa can accumulate EGC and activate galloylation biosynthesis that compete for photoassimilates and reductive power.

Microbial diversity in vineyards and in grapes has generated significant scientific interest. From a biotechnological perspective, vineyard and grape biodiversity has been shown to impact soil, vine, and grape health and to determine the fermentation microbiome and the final character of wine. Thus, an understanding of the drivers that are responsible for the differences in vineyard and grape microbiota is required. The impact of soil and climate, as well as of viticultural practices in geographically delimited areas, have been reported. However, the limited scale makes the identification of generally applicable drivers of microbial biodiversity and of specific microbial fingerprints challenging. The comparison and meta-analysis of different datasets is furthermore complicated by differences in sampling and in methodology. Here we present data from a wide-ranging coordinated approach, using standardized sampling and data generation and analysis, involving four countries with different climates and viticultural traditions. The data confirm the existence of a grape core microbial consortium, but also provide evidence for country-specific microbiota and suggest the existence of a cultivar-specific microbial fingerprint for Cabernet Sauvignon grape. This study puts in evidence new insight of the grape microbial community in two continents and the importance of both location and cultivar for the definition of the grape microbiome.

The Eurasian grapevine (Vitis vinifera), a species cultivated worldwide for high-quality wine production, is extremely susceptible to the agent of downy mildew, Plasmopara viticola. Nevertheless, germplasm from Georgia (Southern Caucasus, the first grapevine domestication centre), characterized by a high genetic variability, showed resistance traits to P. viticola. The cultivar Mgaloblishvili exhibited the most promising phenotype in terms of resistance against P. viticola. Its defence response results in: i) low disease intensity; ii) low sporulation; iii) damaged mycelium; iv) production of antimicrobial compounds such as volatile organic compounds (VOCs), whose effectiveness on the pathogen was evaluated by leafdisc assays. At the transcriptomic level, its resistance mechanism is determined by the differential expression of both resistance and susceptible genes. The resistance genes are related to: i) pathogen recognition through PAMP, DAMP and effector receptors; ii) ethylene signalling pathway; iii) synthesis of antimicrobial compounds (VOCs) and fungal wall degrading enzymes; iv) development of structural barriers (cell wall reinforcement). The first putative susceptible gene was the transcription factor VviLBDIf7 gene, whose validation was carried out by dsRNA (double-stranded RNA) assay. In this work, these unique results on plant-pathogen interaction are reviewed with the aim of developing new strategies to control the disease.

BACKGROUND AND AIMS: The growth and development of grapevine is constrained by temperature, affecting the bulk of physiological processes of the plant. The aim of this study was to evaluate the effects of climate change on thermal resources and limitations in the context of Georgia, one of the oldest viticultural areas in the world. METHODS AND RESULTS: The analysis on daily series of temperature for the time period 1974–2013 for the main viticultural areas of Georgia shows that an abrupt change to warmer temperature occurred in 1994, leading to a decline in low temperature stress and an increase in high temperature stress, associated with more frequent heat waves. The availability of thermal resources for grapevine growth remained unchanged. CONCLUSIONS: In Georgia, the shift to warmer temperature did not affect the availability of thermal resources for grapegrowing. Although some attention should be paid to possible damage due to an earlier budburst and increased frost risk. Furthermore, it is important to highlight the strong increase of summer heatwaves with potential negative impacts on grape composition and phenolic maturity, when combined with severe water stress. SIGNIFICANCE OF THE STUDY: Quantitative studies of the effects of climate change on Georgian viticulture are essential to develop adaptation strategies based on either germplasm (e.g. rootstocks and cultivars) and agronomical practices (e.g. pruning, trellis systems, soil and water management).

International audience; The Near East and the Caucasus are commonly regarded as the original domestication centres of Vitis vinifera (grapevine), and the region continues to be home to a high diversity of wild and cultivated grapevines, particularly within Georgia. The earliest chemical evidence for wine making was recorded in Georgian Neolithic sites (6000-5800 bc) and grape pips, possibly of the domesticated morphotype, have been reported from several sites of about the same period. We performed geometric morphometric and palaeogenomic investigations of grape pip samples in order to identify the appearance of domesticated grapevine and explore the changes in cultivated diversity in relation to modern varieties. We systematically investigated charred and uncharred grape pip samples from Georgian archaeological sites. Their chronology was thoroughly assessed by direct radiocarbon dating. More than 500 grape pips from 14 sites from the Middle Bronze Age to modern times were selected for geometric morphometric studies. The shapes of the ancient pips were compared to hundreds of modern wild individuals and cultivated varieties. Degraded DNA was isolated from three pips from two sites, converted to Illumina libraries, sequenced at approximately 10,000 single nucleotide polymorphism (SNP) sites, and compared to a large public database of grapevine diversity. The most ancient pip dates from the Middle Bronze Age (1900-1500 cal bc) and the domesticated morphotype is identified from ca. 1000 bc onwards. A great diversity of domesticated shapes was regularly seen in the samples. Most are close to modern cultivars from the Caucasian, southwest Asian and Balkan areas, which suggests that the modern local vine diversity is deeply rooted in early viticulture. DNA was successfully recovered from historic pips and genome-wide analyses found close parental relationships to modern Georgian cultivars.

The discovery of new mechanisms of resistance and natural bioactive molecules could be two of the possible ways to reduce fungicide use in vineyard and assure an acceptable and sustainable protection against Plasmopara viticola, the grapevine downy mildew agent. Emission of volatile organic compounds (VOCs), such as terpenes, norisoprenoids, alcohols and aldehydes, is frequently induced in plants in response to attack by pathogens, such as P. viticola, that is known to cause a VOCs increment in cultivars harboring American resistance traits. In this study, the role of leaf VOCs in the resistance mechanism of two resistant cultivars (Mgaloblishvili, a pure Vitis vinifera cultivar, and Bianca, an interspecific hybrid) and the direct antimicrobial activity of four selected VOCs have been investigated. The leaf VOCs profiles, analyzed through solid-phase microextraction gas chromatography-mass spectrometry analysis, as well as the expression of six terpene synthases (TPSs), were determined upon pathogen inoculation. In both cultivars, the expression pattern of six TPSs increased soon after pathogen inoculation and an increment of nine VOCs has been detected. While in Mgaloblishvili VOCs were synthesized early after P. viticola inoculation, they constituted a late response to pathogen in Bianca. All the four terpenes (farnesene, nerolidol, ocimene and valencene), chosen according to the VOC profiles and gene expression analysis, caused a significant reduction (53-100%) in P. viticola sporulation. These results support the role of VOCs into defense mechanisms of both cultivars and suggest their potential role as a natural and eco-friendly solution to protect grapevine from P. viticola.

Grapevine domestication took place in the Caucasus area known as the Cradle of Viticulture, within or near the geographical area known as the Vavilov Triangle. The phytogenetic resources of Vitis sylvestris C.C.Gmel. have been previously collected and characterized, but the study on micro vinifications of wild grapevines from the Caucasus is new. In the present document, seven grape samples from female individuals of wild grapevine growing in the South Caucasus region were investigated to assess their oenological profile. Wine samples were obtained from the grapes collected from various populations of Armenia, Azerbaijan and Georgia in October 2013 and fermented by the native yeasts. Parameters determined in the wines were, among others, the concentration of ethanol (3.63 % - 10.15 %), pH (3.30 - 4.20), total acidity (1.2 - 10.7 g/L of tartaric acid), total polyphenol index (1.81 - 89.8) and colour intensity (2.59 - 20.76). This wide range of values is due to the different environmental conditions, the level of ripeness of harvested grapes and their genetic diversity. These data were compared with those obtained in micro vinifications of wild grapevines in Western Europe and wines of several international cultivars. The results of our research demonstrated, that the must of wild grape could be used to improve traditional wines giving them more colouration. This work was carried out under the project COST FA1003 Action “East–West Collaboration for Grapevine Diversity and Exploration and Mobilization of Adaptive Traits for Breeding” (2014-2018).

A prospecting of habitats and mechanical support host species for the climber Eurasian wild grapevine, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi, was carried out on 13 natural populations situated along river bank forests, floodplains and colluvial positions in Georgia (Marneuli, Mtskheta and Gori districts, Gardabani Protected area and Lagodekhi Reserve), Armenia (Akhtala and Tavoush regions) and Azerbaijan (Quba region) during survey of 2013. The research demonstrated that Eurasian wild grapevine (Vitis vinifera subsp. sylvestris) is found in Southern Caucasus in a wide variety of habitats always linked to water availability. Punica granatum trees are the commonest mechanical support for wild grapevine in the South Caucasus and Hedera helix often shares the same support trees. However we documented wild grapevines climbing on other 24 different species of trees and large shrubs and, further, 32 associated species. We determined, four different clusters of localities using Structure software and the Weighted Neighbor Joining tree. These clusters are characterized by specific mechanical support and accompanying species. Other vines competing for host with Eurasian wild grapevine belong to the genera Clematis, Hedera, Humulus, Smilax and Vitis ssp. Keywords: Armenia, Azerbaijan, Georgia, Lianas, Vines, Wild grapevines

A survey carried out in Georgian vineyards, located in the Khaketi region, in September 2013, showed the presence of vines of the cultivar Chardonnay with typical grapevine yellows (GY) symptoms including leaf discoloration and curling, berry shriveling, and irregular maturation of wood. In the same vineyards, bindweed (Convolvulus arvensis L.) plants showing shoot proliferation and leaf yellowing were found, suggesting the involvement of phytoplasmas in the disease etiology. Total DNA was extracted by a CTAB method from leaf veins of 18 symptomatic and two asymptomatic grapevines, and from four symptomatic and two asymptomatic bindweeds, and analyzed by PCR assays. Moreover, DNA extracted from ‘Candidatus Phytoplasma asteris’ strain SAY (group 16SrI), ‘Ca. P. solani’ strain STOL (group 16SrXII), and ‘Ca. P. ulmi’ strain EY1 (group 16SrV) were used as positive controls. DNA extracted from healthy periwinkle and a reaction mixture without template were employed as negative controls. Nested PCRs targeting the 16S rDNA, carried out using the primer pairs P1/P7 followed by R16F2n/R16R2 (1), produced a band of the expected size (1,250 nt) in all the symptomatic grapevine and bindweed plants, and in the positive controls. No amplification was observed with DNA from asymptomatic plants nor the negative controls. PCR products were sequenced by a commercial sequencing service (Primm, Milan, Italy). The 16S rDNA nucleotide sequences of phytoplasmas identified in all grapevines and in two bindweed samples shared >99.5% sequence identity with ‘Ca. P. solani’ reference strain STOL (GenBank Accession No. AF248959), and carried identical STOL-unique signature sequence and distinguishing sequence blocks (3). Moreover, nucleotide sequences of phytoplasmas identified in the other two bindweed samples shared >99.6% sequence identity with ‘Ca. P. convolvuli’ reference strain BY-S57/11 (JN833705) (2). RFLP and phylogenetic analyses confirmed the affiliation of the phytoplasma strains identified in grapevine and bindweed plants in Georgia to the species ‘Ca. P. solani’ (subgroup 16SrXII-A) and ‘Ca. P. convolvuli’ (subgroup 16SrXII-H). Representative 16S rDNA nucleotide sequences were deposited in NCBI GenBank website with accession nos. KF996535 and KF996536 (‘Ca. P. solani’ from grapevine and bindweed, respectively), and KF996537 (‘Ca. P. convolvuli’). Future studies will focus on investigating the spread and impact of ‘Ca. P. solani’-associated bois noir (BN) in Georgia. In particular, the identification of ‘Ca. P. solani’ in bindweeds suggested the presence of the insect Hyalesthes obsoletus, a polyphagous cixiidae responsible for BN phytoplasma transmission in vineyards in Europe. Accurate surveys and molecular analyses will be performed for identifying the insect vector(s) of the BN associated phytoplasma strains in Georgia. Additional studies will be performed to study the spread and impact of ‘Ca. P. convolvuli,’ identified only in Italy, Germany, Serbia, and Bosnia and Herzegovina (2), throughout the Caucasian countries. References: (1) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) M. Martini et al. Int. J. Syst. Evol. Microbiol. 62:2910, 2013. (3) F. Quaglino et al. Int. J. Syst. Evol. Microbiol. 63:2879, 2013.

Radio frequency observations supplement optical studies and in some cases they are the only way of obtaining information on the physical conditions for radio waves and their propagation. Solar radio emission appears in two forms, “quiescent” and “sporadic.” Their distinctive features are well known. Solar radio observations at meter wavelengths (λ = 1.43 m, ν = 210 MHz) have been made at the Abastumani Astrophysical Observatory using a solar radio telescope throughout five solar cycles (since 1957). This article is a study of the long-term observations of solar radio bursts and sunspots. It is found that there is a correlation between the amplitudes of the radio bursts, the number of spots, and the regions of the spots.

Evidence from a preliminary survey highlighted that ‘Candidatus Phytoplasma solani’, the etiological agent of bois noir (BN) disease of grapevine, infects grapevine varieties in Georgia, a country of the South Caucasus. In this study, field surveys were carried out to investigate the BN symptom severity in international and Georgian native varieties. ‘Ca. P. solani’ was detected and identified by polymerase chain reaction-based amplification and restriction fragment length polymorphism analysis of 16S ribosomal DNA, and further characterized by multiple gene typing analysis (vmp1 and stamp genes). Obtained data highlighted that the majority of Georgian grapevine varieties showed moderate and mild symptoms, whereas international cultivars exhibited severe symptoms. Molecular characterization of ‘Ca. P. solani’ from grapevine revealed the presence of 11 distinct phytoplasma types. Only one type (VmGe12/StGe7) was identical to a strain previously reported in periwinkle from Lebanon; the other ‘Ca. P. solani’ types are described here for the first time. Phylogenetic analyses of vmp1 and stamp gene concatenated nucleotide sequences showed that ‘Ca. P. solani’ strains in Georgia are associated mainly with the bindweed-related BN host system. Moreover, the fact that ‘Ca. P. solani’ strains are distributed in grapevine cultivars showing a range of symptom intensity suggests a different susceptibility of such local cultivars to BN.

Background The mountainous region between the Caucasus and China is considered to be the center of domestication for grapevine. Despite the importance of Central Asia in the history of grape growing, information about the extent and distribution of grape genetic variation in this region is limited in comparison to wild and cultivated grapevines from around the Mediterranean basin. The principal goal of this work was to survey the genetic diversity and relationships among wild and cultivated grape germplasm from the Caucasus, Central Asia, and the Mediterranean basin collectively to understand gene flow, possible domestication events and adaptive introgression. Results A total of 1378 wild and cultivated grapevines collected around the Mediterranean basin and from Central Asia were tested with a set of 20 nuclear SSR markers. Genetic data were analyzed (Cluster analysis, Principal Coordinate Analysis and STRUCTURE) to identify groups, and the results were validated by Nei’s genetic distance, pairwise FST analysis and assignment tests. All of these analyses identified three genetic groups: G1, wild accessions from Croatia, France, Italy and Spain; G2, wild accessions from Armenia, Azerbaijan and Georgia; and G3, cultivars from Spain, France, Italy, Georgia, Iran, Pakistan and Turkmenistan, which included a small group of wild accessions from Georgia and Croatia. Wild accessions from Georgia clustered with cultivated grape from the same area (proles pontica), but also with Western Europe (proles occidentalis), supporting Georgia as the ancient center of grapevine domestication. In addition, cluster analysis indicated that Western European wild grapes grouped with cultivated grapes from the same area, suggesting that the cultivated proles occidentalis contributed more to the early development of wine grapes than the wild vines from Eastern Europe. Conclusions The analysis of genetic relationships among the tested genotypes provided evidence of genetic relationships between wild and cultivated accessions in the Mediterranean basin and Central Asia. The genetic structure indicated a considerable amount of gene flow, which limited the differentiation between the two subspecies. The results also indicated that grapes with mixed ancestry occur in the regions where wild grapevines were domesticated. Electronic supplementary material The online version of this article (10.1186/s12870-018-1351-0) contains supplementary material, which is available to authorized users.

The objective of this work is to investigate the Holocenic climate cycles that may have influenced the domestication of grapevine in the Subcaucasian area and its subsequent spread in Eurasia. The analysis covered the longitudinal belt ranging from the Iberian Peninsula to Japan, seen as the preferential pathway for the Holocenic spread of grapevine and many other crops in Eurasia. Spectral analysis was considered as the criterion of investigation and the Holocenic cycles were analyzed considering different geochemical and biological proxies, of which seven are directly referred to vine. In this context the relation of the abovementioned proxies with spectral peaks of possible causal factors like Solar activity (SA), North Atlantic oceanic factors (Atlantic Multidecadal Oscillation - AMO and North Atlantic Oscillation - NAO), and subtropical oceanic factors (El Nino Southern Oscillation - ENSO) was also analyzed. In order to acquire a sufficiently wide number of proxies sensitive to the causal factors, we referred to a latitudinal belt wider than the one colonized by vine, also acquiring proxy from the Scandinavian area, notoriously susceptible to North Atlantic forcings. The analysis of the proxy spectral peaks, considering 20 classes with a 50-years step in the 0–1000 years range, showed that the 50% of the classes have a higher frequency of peaks at East than West, the 20% a higher frequency at West than East and the 10% an equal frequency, showing the efficiency of the propagation of Western signals towards the center of Eurasia. The search of the causal factors spectral peaks in the proxy series showed that AMO, NAO and SA acted with a certain regularity on the entire belt investigated both latitudinally and longitudinally, while spectral peaks linked to ENSO underwent a considerable attenuation moving northward. Finally, the specific analysis on viticultural proxies showed common peaks with causal factors.

Grape condensed tannins (proanthocyanidins) are phenolic substances of utmost importance in the sensory characteristics of wine. Not only does their final concentration affect the fermentation process, but their structure also greatly influences the negative attribute of astringency. Determining the exact amount of proanthocyanidins in the grape pericarp is a real challenge, and a prerequisite in any breeding research program aimed at the improvement of the quality of grape berry tannins. We analyzed pericarp condensed tannins in four species of Asian and American wild grape vines in comparison with four accessions of the domestic grape vine, Vitis vinifera. The mass of tannins per berry ranged from 0.1 to 1.2% FW; however, the relative mole percentage of epigallocatechin in Asian species was 10 times lower than in American species and the domestic grape vine, while the tannin galloylation degree of American vines was 4 and 10 times higher than in domestic and Asian vines, respectively.

Georgia is a traditional country of viticulture and winemaking but only a few studies have been focused on wines originating from this area. In this study, we compared antioxidant effect, total sulfite content and concentration of 14 phenolic compounds of some native Georgian red and white wines with wines commonly produced in Central and Western Europe. Georgian red wines exhibited higher antioxidant capacity in DPPH, ORAC and total phenolic content assay. Further, Georgian red wines were richer in quercetin, kaempferol and syringic acid content, while the concentration of trans -resveratrol was lower than in Central and West European red wines. While differences among red wines from different origins and cultivars were observed, winemaking technology was the most important factor in the case of white wines. Kakhetian method increased antioxidant effect and levels of some phenolic compounds in comparison with white wines prepared by common European method. Our findings suggest that Georgian wines deserve further attention because of their high content of phenolics and high antioxidant capacity.

The peach is a traditional and well known stone fruit in Georgia, considering that it was introduced from China and Iran and has been cultivated here since ancient time. Actually Prunus persica (L.) Batsch is spread in Georgia for commercial purposes. There are grouped local varieties according of pedoclimatic condition: Kakheti peaches (large, yellow flesh fruits), Kartli peaches (crisp white flesh, good aroma and taste), West Georgia peaches (small fruits, with tolerance to humidity). The peach production basically is located in East Georgia – Kakheti and Shida kartli region. The principal production area is Kakheti, mostly Gurjaani district. The peach orchards plantation comprised on 3,100 ha commercial orchards and scattered trees on 1,600 ha. The average production of peach varies from 19,100 Mt (2009) till 5,300 Mt (2006) per year. The common practice of planting commercial orchards of peach – 500-600 trees/ha with training method of Vase. The late spring frosts during blossom is a major limiting factor for increasing peach production in country. The peach leaf curl (Taphrina deformans), San Jose scale (Quadraspidiotus perniciosus (Comstock), peach twig borer (Anarsia lineatella) and the Oriental fruit moth (Grapholita molesta) are main troubles for the industry. The important commercial features of peaches which are produced in the country – attractive view, large size and distinguished taste and aroma – gives marketing advantages in the local and export market. A number of research works (Kvaliashvili, Maghradze, Vashakidze) have been done during last several decades in direction of peach improvement in Georgia. As a result of this work several new varieties of peach (‘Tsedisuri Pink’, ‘Tsedisuri Flat’, ‘Albest’, ‘Atenuri Yellow’ and others) have been released, which are distinguished by productivity, good aroma and taste. Research work for trial and evaluation of performance over 50 new introduced cultivars is in progress (Bobokashvili).

Significance The earliest biomolecular archaeological and archaeobotanical evidence for grape wine and viniculture from the Near East, ca. 6,000–5,800 BC during the early Neolithic Period, was obtained by applying state-of-the-art archaeological, archaeobotanical, climatic, and chemical methods to newly excavated materials from two sites in Georgia in the South Caucasus. Wine is central to civilization as we know it in the West. As a medicine, social lubricant, mind-altering substance, and highly valued commodity, wine became the focus of religious cults, pharmacopoeias, cuisines, economies, and society in the ancient Near East. This wine culture subsequently spread around the globe. Viniculture illustrates human ingenuity in developing horticultural and winemaking techniques, such as domestication, propagation, selection of desirable traits, wine presses, suitable containers and closures, and so on., Chemical analyses of ancient organic compounds absorbed into the pottery fabrics from sites in Georgia in the South Caucasus region, dating to the early Neolithic period (ca. 6,000–5,000 BC), provide the earliest biomolecular archaeological evidence for grape wine and viniculture from the Near East, at ca. 6,000–5,800 BC. The chemical findings are corroborated by climatic and environmental reconstruction, together with archaeobotanical evidence, including grape pollen, starch, and epidermal remains associated with a jar of similar type and date. The very large-capacity jars, some of the earliest pottery made in the Near East, probably served as combination fermentation, aging, and serving vessels. They are the most numerous pottery type at many sites comprising the so-called “Shulaveri-Shomutepe Culture” of the Neolithic period, which extends into western Azerbaijan and northern Armenia. The discovery of early sixth millennium BC grape wine in this region is crucial to the later history of wine in Europe and the rest of the world.

The increasing level of hazardous residues in the environment and food chains has led the European Union to restrict the use of chemical fungicides. Thus, exploiting new natural antagonistic microorganisms against fungal diseases could serve the agricultural production to reduce pre- and post-harvest losses, to boost safer practices for workers and to protect the consumers' health. The main aim of this work was to evaluate the antagonistic potential of epiphytic yeasts against Botrytis cinerea, Aspergillus carbonarius, and Penicillium expansum pathogen species. In particular, yeast isolation was carried out from grape berries of Vitis vinifera ssp sylvestris populations, of the Eurasian area, and V. vinifera ssp vinifera cultivars from three different farming systems (organic, biodynamic, and conventional). Strains able to inhibit or slow the growth of pathogens were selected by in vitro and in vivo experiments. The most effective antagonist yeast strains were subsequently assayed for their capability to colonize the grape berries. Finally, possible modes of action, such as nutrients and space competition, iron depletion, cell wall degrading enzymes, diffusible and volatile antimicrobial compounds, and biofilm formation, were investigated as well. Two hundred and thirty-one yeast strains belonging to 26 different species were isolated; 20 of them, ascribed to eight species, showed antagonistic action against all molds. Yeasts isolated from V. vinifera ssp sylvestris were more effective (up to 50%) against B. cinerea rather than those isolated from V. vinifera ssp vinifera. Six strains, all isolated from wild vines, belonging to four species (Meyerozyma guilliermondii, Hanseniaspora uvarum, Hanseniaspora clermontiae, and Pichia kluyveri) revealed one or more phenotypical characteristics associated to the analyzed modes of antagonistic action.

The distribution and survival of trees during the last glacial maximum (LGM) has been of interest to paleoecologists, biogeographers, and geneticists. Ecological niche models that associate species occurrence and abundance with climatic variables are widely used to gain ecological and evolutionary insights and to predict species distributions over space and time. The present study deals with the glacial history of walnut to address questions related to past distributions through genetic analysis and ecological modeling of the present, LGM and Last Interglacial (LIG) periods. A maximum entropy method was used to project the current walnut distribution model on to the LGM (21-18 kyr BP) and LIG (130-116 kyr BP) climatic conditions. Model tuning identified the walnut data set filtered at 10 km spatial resolution as the best for modeling the current distribution and to hindcast past (LGM and LIG) distributions of walnut. The current distribution model predicted southern Caucasus, parts of West and Central Asia extending into South Asia encompassing northern Afghanistan, Pakistan, northwestern Himalayan region, and southwestern Tibet, as the favorable climatic niche matching the modern distribution of walnut. The hindcast of distributions suggested the occurrence of walnut during LGM was somewhat limited to southern latitudes from southern Caucasus, Central and South Asian regions extending into southwestern Tibet, northeastern India, Himalayan region of Sikkim and Bhutan, and southeastern China. Both CCSM and MIROC projections overlapped, except that MIROC projected a significant presence of walnut in the Balkan Peninsula during the LGM. In contrast, genetic analysis of the current walnut distribution suggested a much narrower area in northern Pakistan and the surrounding areas of Afghanistan, northwestern India, and southern Tajikistan as a plausible hotspot of diversity where walnut may have survived glaciations. Overall, the findings suggest that walnut perhaps survived the last glaciations in several refugia across a wide geographic area between 30° and 45° North latitude. However, humans probably played a significant role in the recent history and modern distribution of walnut.

Grape skin color is among the most important qualitative traits on which selection is based in wine and table grape breeding programmes. Skin color is determined by the quantity and composition of anthocyanins. In prior work on cultivated forms, it was shown that polymorphisms in the grape transcription factor family VvMYBA are responsible for anthocyanin content variation in the berries of cultivated grapevine (Vitis vinifera subsp. vinifera). Wild grapevine (V. vinifera subsp. sylvestris) is the ancestor of the cultivated V. vinifera subsp. sativa and has black-colored berries. The purpose of this study was to determine how the VvmybA1 and VvmybA2 polymorphisms emerged and affected the genetic diversity of wild grapevines in the Mediterranean basin by examining samples from the Iberian Peninsula, Italian Peninsula and Caucasian region. Our observations provide evidence that variation in the two transcriptional regulators generated a novel allele series via length polymorphisms in VvmybA1 and a point mutation in VvmybA2, which is lacking in cultivated grapevine. Further, correlation was detected between allele composition and anthocyanin contents. According to polymorphisms in both VvMYBA genes at the color locus, we were able to identify several haplotypes. The most ancestral haplotype (HapN) was found in wild grapevine in the western Mediterranean region and corresponded to wine grape cultivars, whereas recent haplotypes were detected in eastern regions. These eastern zones showed the most diverse haplotypes, which appeared in table cultivars where intense breeding practices may have replaced the original haplotype diversity. These findings provide information about the evolution of grapes since their domestication and have direct implications for wine quality. © 2014, Springer-Verlag Wien.

This is a study of the development of sixteen chromospheric flares observed at the Abastumani Astrophysical Observatory in 1973. Hα filtergrams and radio bursts at a frequency of 210 MHz (λ=1.43 m) are examined. The Hα filtergrams were obtained using a chromosphere-photosphere telescope with the aid of an interference polarization filter and the radio bursts were detected using the radio telescope at the Abastumani Observatory. The main purpose of this work is to detect radio signals associated with the flares. In most cases the area of the flare and its intensity reached their maxima almost simultaneously. As for the peak energy release, in most cases it reached a maximum at almost the same time or slightly earlier in the meter radio wavelength band than in the Hα line. The sequence of events in the optical and radio bands during the flares is obtained by using the method of epoch superposition.

International audience; The South Caucasus area is considered one of the main centers of origin and domestication for the cultivated grapevine V. vinifera L. sativa. The aim of this work is to study the genetic structure of Georgian grapevines by analyzing 135 Georgian grapevine accessions using 20 SSR molecular markers and to verify the contribution of Georgian germplasm to the European viticulture. Among the 135 selected samples 112 are representatives of the traditional wine making Georgian varieties and 23 were collected from several Georgian woodlands and, after visual inspection, were considered representatives of Vitis vinifera sylvestris subspecies. Molecular fingerprints (20 SSR loci) of all the 135 accessions were compared with data from the 2300 accessions conserved at the Institut National de la Recherche Agronomique (INRA) grape germplasm repository of Domaine de Vassal. Nei’s genetic distance was calculated among the Vassal and Georgian samples and a dendrogram was built to verify the presence of synonyms and to have an overview of the structure of Georgian grapevine germplasm compared with the ones belonging to other countries. Results highlighted that most of Georgian viticulture is quite isolated from elsewhere. These results seem to confirm that the Georgian typical varieties didn’t spread to other European countries and, on the other hand Georgian viticulture did not have gene flow from elsewhere. To verify the existence of parent-offspring relationships, the software MLrelate and Famoz were used to analyze the dataset (Domaine de Vassal and Georgian accessions). Interesting relationships were identified especially between Georgian samples and among Georgian and neighbor countries. The apparent isolation of Georgian germplasm makes this viticulture particularly interesting to be investigated, and for this reason we used Identity and Microsat software to describe the structure of these samples and to perform a study on allele frequencies and characterization. The results suggest that the Georgian viticulture is still strongly correlated to its geographic origin, allowing us to clearly distinguish groups of accessions belonging to different regions of the country. In the wild samples, the molecular fingerprint has revealed very few mistakes or inter-specific crossings in the pool of collected samples and highlighted that, as already verified for other regions, there is diversification among the wild and cultivated compartments, even if this separation doesn’t seem to be, in the Georgian case, as robust as seen in other viticultural areas.

One of the results of the “Research Project for the Study of Georgian Grapes and Wine Culture” promoted by the National Wine Agency of the Republic of Georgia was the production of a bilingual handbook for modern viticulture. The first sections of the handbook were devoted to the agrometeorological analysis of environmental resources and limitations, comprising a general analysis of Georgian climate and agrometeorological features, followed by detailed regional cards. The agrometeorological analysis of Georgia was based on daily data collected by National and International networks for the period 1974-2013. Several agrometeorological indexes were calculated in order to define resources and limitations for viticulture for each viticultural region of Georgia, providing fundamental information for grape-growing and wine-making.

International audience; This communication will provide the latest information about the progress of the "Research Project for the Study of Georgian Grapes and Wine Culture", managed by the National Wine Agency of Georgia since 2014. Local and foreign institutions continue to work together with the aim of stimulating multidisciplinary scientific research activity on Georgian viticulture and viniculture and to reconstruct their development from Neolithic civilizations to the present. The project is multidisciplinary in nature, merging contributions from archaeology, history, ethnography, molecular genetics, biomolecular archaeology, palaeobotany, ampelography, enology, climatology and other scientific fields.

Introduction The colour of fruit is an important quality factor for cultivar classification and phenotyping techniques. Besides the subjective visual evaluation, new instruments and techniques can be used. Objectives This work aims at developping an objective, fast, easy and non-destructive method as a useful support for evaluating grapes' colour under different cultural and environmental conditions, as well as for breeding process and germplasm evaluation, supporting the plant characterization and the biodiversity preservation. Materials and Methods Colours of 120 grape varieties were studied using reflectance spectra. The classification was realized using cluster and discriminant analysis. Reflectance of the whole berries surface was also compared with absorption properties of single skin extracts. Results A phenotyping method based on the reflectance spectra was developed, producing reliable colour classifications. A cultivar-independent index for pigment content evaluation has also been obtained. Conclusions This work allowed the classification of the berry colour using an objective method. Copyright © 2013 John Wiley & Sons, Ltd.

In Georgia, one of the most ancient vine-growing environment, the homemade production of wine is still very popular in every rural family and spontaneous fermentation of must, without addition of chemical preservatives, is the norm. The present work investigated the yeast biodiversity in five Georgian areas (Guria, Imereti, Kakheti, Kartli, Ratcha-Lechkhumi) sampling grapes and wines from 22 different native cultivars, in 26 vineyards and 19 family cellars. One hundred and eighty-two isolates were ascribed to 15 different species by PCR-ITS and RFLP, and partial sequencing of D1/D2 domain 26S rDNA gene. Metschnikowia pulcherrima (F’ = 0.56, I’ = 0.32), Hanseniaspora guilliermondii (F’ = 0.49, I’ = 0.27), and Cryptococcus flavescens (F’ = 0.31, I’ = 0.11) were the dominant yeasts found on grapes, whereas Saccharomyces cerevisiae showed the highest prevalence into wine samples. Seventy four isolates with fermentative potential were screened for oenological traits such as ethanol production, resistance to SO2, and acetic acid, glycerol and H2S production. Three yeast strains (Kluyveromyces marxianus UMY207, S. cerevisiae UMY255, Torulaspora delbrueckii UMY196) were selected and separately inoculated in vinifications experiments at a Georgian cellar. Musts were prepared from healthy grapes of local varieties, Goruli Mtsvane (white berry cultivar) and Saperavi (black berry cultivar). Physical (°Brix) and microbial analyses (plate counts) were performed to monitor the fermentative process. The isolation of indigenous S. cerevisiae yeasts beyond the inoculated strains indicated that a co-presence occurred during the vinification tests. Results from quantitative GC-FID analysis of volatile compounds revealed that the highest amount of fermentation flavors, such as 4-ethoxy-4-oxobutanoic acid (monoethyl succinate), 2-methylpropan-1-ol, ethyl 2-hydroxypropanoate, and 2-phenylethanol, were significantly more produced in fermentation conducted in Saperavi variety inoculated with K. marxianus, whereas other aromatic compounds like 3-methylbutyl acetate, ethyl hexanoate and dihydrofuran-2(3H)-one (γ- butyrolactone) showed a higher content in Goruli Mtsvane variety samples fermented by S. cerevisiae. The selected yeast strains have proved to be promising for enhancing the flavor potential in low aromatic Georgian cultivars. This work intends to be a knowledge contribution for a precision oenology toward the strategic concept of “one grape variety-one yeast”.

In 2014, the National Wine Agency of the Republic of Georgia initiated a three-year "Research Project for the study of Georgian Grapes and Wine Culture. Through collaborative research by Georgian and foreign institutions and researchers, the project aims to: stimulate research of Georgian viticulture and viniculture, through the lens of the country with the earliest tradition of grape domestication and winemaking; and to reconstruct the continuous development of viticulture and wine culture through time. The project advances the study of grape and wine culture by utilizing a multidisciplinary approach, including: archaeology, history, ethnography, molecular genetics, biomolecular archaeology, palaeobotany, ampelography, enology, climatology and other scientific fields. These studies are diachronic in their approach, beginning with the oldest Neolithic civilizations, to present day, creating a holistic understanding of the continuity and complexity of Georgian Wine Culture to help popularize Georgian Wine throughout the global wine market.

Vitis vinifera L. ssp. sylvestris grows principally in well preserved natural habitats. Its survival is threatened mainly by human land use practices. In spite of its importance as a progenitor of cultivated forms, very little research has been devoted to the study of its distribution and genetic structure. During the period 2007-2009 a census was carried out in 9 of the 20 Italian regions with major intensification in 4 of them. Eight hundred and twenty plants corresponding to 165 sites were found. Over 50% of these were localized in two regions only. After collection of the wooden material for greenhouse propagation and after rooting of the cuttings, samples were taken to perform genetic analysis using 10 nuclear SSR markers. Some genetic parameters (Ne, Ho, He, Fis, Fst and I) were calculated on the allelic size, grouping plants once for locus and once for region of origin. The results showed Italian wild grapevine expressed altogether high biodiversity and low rate of isolation. In particular plants from Sicilia, in spite of their low number, stood out for their high heterozigosity and low inbreeding and isolation level. This particularity brought the same plants to have the high genetic distance in the NJ phylogenetic tree. PCA analysis separated in 2 well-defined groups along the first component without correspondence with geographical grouping. AMOVA analysis confirmed that the highest variance was placed within populations (only 5% of the overall variance was placed among populations). SSR marker analysis is still in progress to verify the existence of introgression among wild and cultivated compartments and to comprehend the extent of factors driving the genetic structure and the possible pattern of dissemination of wild grapevine in Italy.