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Prirodno pjenušavo ružičasto vino od autohtonog kultivara vinove loze Teran (Vitis vinifera L.) proizvedeno je metodom vrenja u boci uz primjenu inkapsuliranog kvasca ProElif® (Saccharomyces cerevisiae) i komercijalnog suhog kvasca Fermol Blanc (Saccharomyces bayanus). Tijekom istraživanja uspoređivana je aktivnost korištenih kvasaca s obzirom na brzinu razgradnje šećera tijekom fermentacije u boci te njihov utjecaj na osnovna fizikalno kemijska svojstva i fenolni profil gotovog pjenušavog vina te parametre pjene i iskrenja. Brža razgradnja šećera, kao i veći udio pojedinačnih i ukupnih fenolnih spojeva utvrđen je u pjenušavim vinima proizvedenim primjenom inkapsuliranog kvasca ProElif®. S druge strane, vina proizvedena kvascem Fermol Blanc odlikovala su se višim suhim ekstraktom te većom kvalitetom pjene i iskrenja. Uočene senzorske razlike u vinima nisu imale negativnih implikacija pri definiranju njihove sveobuhvatne kakvoće, The influence of encapsulated yeast ProElif® (Saccharomyces cerevisiae) in comparison with the yeast Fermol Blanc (Saccharomyces bayanus) in the production of naturally sparkling rosé wine by bottle fermentation produced from the indigenous grape cultivar Teran (Vitis vinifera L.) was investigated. During the research, the following were monitored: the length of sugar decomposition during fermentation in the bottle, and in the finalized sparkling wines, physicochemical parameters, foam and sparkling parameters and phenolic profile. Faster breakdown of sugars, as well as a higher proportion of individual and total phenolic compounds have been recorded in wines with ProElif® yeast. On the other hand, wines produced with Fermol Blanc yeast were characterized by a higher dry extract and higher quality of foam and sparkling. Sensory differences were observed in wines without negative implications for their final quality.

Anecdotal observations have shown that there is often incoherence between sugar accumulation and evolution of grape flavour during later ripening stages. For this reason, an experiment with Malvazija istarska (Vitis vinifera L.) was conducted to investigate the relationship between harvest date and changes in the abundance of wine volatile aroma compounds. Malvazija grapes were harvested and subsequently vinified at three harvest dates (H1 – H3) separated from each other by approximately 10 days, with grape quality parameters at each date suitable for production of standard still white wines. Wine volatile aroma compounds were analysed by comprehensive two- dimensional gas chromatography with time-of-flight mass spectrometry combined with conventional one- dimensional GC/MS and were statistically elaborated. Various terpenes and alcohols were found in the highest concentration in wines from the grapes harvested at H3. Most of fermentation aroma compounds showed no significant differences. The exceptions were ethyl-2-methylbutyrate, ethyl propanoate and isobutyl decanoate found in the highest concentrations in wines from H3 and isopropyl acetate and isoamyl decanoate in wines from H1. The obtained results confirmed that by choosing the harvest date it is possible to significantly influence the composition of volatile aroma compounds in white wine. This study was funded by Croatian Science Foundation under the projects IP-2020-02-4551 and DOK2021-02-5500.

Besides its hedonic nature, wine is a natural beverage with certain health-related properties, which is why the consumer’s interest towards wines with a higher concentration of bioactive compounds has increased over recent years. Extracted from grapes, antioxidants and vitamins are naturally present in wines but their concentrations differ according to the applied winemaking technique. The maceration process is less frequently carried out for the production of white wines in relation to red wines for several reasons, but its application may be suggested to increase wine antioxidant capacity and nutritional value. The aim of this study was to investigate the effect of applying different maceration processes on antioxidant capacity and vitamin content of wines produced from an autochthonous Croatian white grape variety, Malvazija istarska (Vitis vinifera L.). Vinification took place in vintage 2019 at the Institute of Agriculture and Tourism (Poreč, Croatia) where six vinification treatments were carried out: non-maceration control treatment (C), pre-fermentative two days cryomaceration treatment at 8 °C (CRYO), seven days maceration treatment at 16 °C (M7), and prolonged post-fermentative maceration treatments at 16 °C for 14 days (M14), 21 day (M21), and 42 days (M42). The antioxidant capacity of the wines was determined by the ferric reducing/antioxidant power, FRAP (mM Fe2+) assay and the oxygen radical absorbance capacity, ORAC (mM Trolox) assay. Chromatographic analyses were performed on a liquid chromatography system with a DAD and single quadrupole mass detector equipped with electrospray ionization interface. Identification of five vitamins (B1, B2, B3, B6 and C) was carried out by comparison to the retention times of authentic standards and their spectral properties. Statistical data analysis was performed using one-way analysis of variance (ANOVA) and Fischer’s least significant difference (LSD). According to both FRAP and ORAC assay, antioxidant capacity increased proportionally with the maceration duration, with control treatment wine having the lowest, opposed to M42 treatment wine having the highest values. Such results indicate that the antioxidant properties are mostly related to phenolic compounds which are mainly present in prolonged maceration treatments such as M42. Contrary results were noted for vitamin C content that showed a decreasing trend as maceration progressed. Vitamin C was not detected in M42 treatment wine while the highest concentration was reported in control treatment wine. When observing total B-group vitamins, a significant difference was noted between treatments. Prolonged post-fermentative maceration treatment M42 resulted with the highest concentration of total B-group vitamins in relation to other treatments. The increase in total B-group vitamin was proportional with maceration time, while CRYO and M7 treatments did not significantly differ from control treatment wine. Regarding the concentrations of each individual vitamin, vitamin B3 reached the highest values, and its concentration was significantly the highest in M42 treatment wine. A similar trend was noted in the concentration of vitamin B6. Obtained results showed that prolonged maceration significantly affects both the antioxidant capacity of the wines and their vitamin content, particularly B-group vitamins. Such information may serve producers for choosing the adequate technological practice for improving wine quality and its nutritional value. The study was funded by the Croatian Scientific Foundation under the projects VINUM SANUM (IP 2018-5049) and DOK-2020-01-1901.

The aim of this work was to determine the relationship between some aroma sensory descriptors and wine quality scores of white wines made from cv. Malvazija istarska (Vitis Vinfera L.). Six different vinification techniques were carried out: control treatment – fast grape processing without maceration (BP), fast grape processing with the addition of oenological tannin (BPT), pre-fermentative cold 1-day maceration (MM1), 7 days maceration (MM7), 21 days maceration (MM21) and vinification of dried grapes (MP) of cv. Malvazija istarska. Sensory profile of wine samples was obtained using both quantitive descriptive analysis (QDA) and 100 points O.I.V/U.I.O.E. evaluation method. The results showed a positive correlation between the presence of fruit and floral aroma attributes and overall wine impression. All observed treatments contributed to the positive effect on fruit and floral aromatic profile and overall wine impression in respect to control treatment.

The aim of this study was to establish the relationship between some sensory attributes and the overall impression of native Croatian red wine variety Teran (Vitis vinifera L.). Wines were produced with four different vinification techniques: control (7-days maceration, TM7), prolonged maceration 10 and 21 days (TM10, TM21 respectively), and pre- fermentation heating treatment (TPHT). The sensory profile of wine samples was obtained using quantitative descriptive analysis (QDA) and 100 points O.I.V/U.I.O.E. evaluation method. Five panelists rated the intensity of body/fullness, astringency, viscosity, aftertaste quality, and varietal typicity of taste. The results showed a positive correlation between the intensity of most taste attributes and the overall wine impression. A strong negative correlation was observed for astringency. All observed treatments, highlighting post-fermentative prolonged 21-day maceration and pre-fermentation heating treatment, contributed to the positive effect on taste profile and overall wine impression regarding control treatment.

Malolactic fermentation (MLF) is a complex biochemical process playing an important role in the production of red wines. The main reasons for its implementation are the reduction of titratable acidity and the consequent increase of pH, microbiological stability of wine, and changes in aromatic and sensory properties of wine. The aim of this study was to determine the compatibility of yeast and bacteria used by different malolactic fermentation techniques and their influence on the fermentation duration, concentration of individual organic acids, aroma compounds, and on chemical and sensory properties of Teran wines. The experiment included control treatment (without MLF), spontaneous MLF, induced MLF at the beginning of alcoholic fermentation with simultaneous inoculation of yeast and bacteria (coinoculation) and induced MLF after alcoholic fermentation (sequential MLF). In the co-inoculation treatment MLF had no negative effect on the alcoholic fermentation kinetic. Alcoholic fermentation was complete in all treatments. Coinoculation resulted in a significantly shorter duration of the MLF process. In all MLF treatments, significant reduction of titratable acidity and the increase of pH values was noted. Wines of the spontaneous MLF treatment obtained the highest concentration of volatile acidity and ethyl acetate. In all MLF treatments a complete consumption of malic acid and a decrease in concentration of citric acid, total amount of higher alcohols, and acetaldehyde were observed. Furthermore, significantly higher concentrations of ethyl esters, diacetyl, acetoin, and 2,3 butanediol were present in wines from all MLF treatments., Jabučno-mliječna fermentacija (JMF) složen je biokemijski proces koji ima važnu ulogu u proizvodnji većine crnih vina. Glavni učinci primjene JMF su snižavanje ukupne kiselosti uz rast pH vrijednosti, mikrobiološka stabilnost vina te promjena aromatskih senzornih svojstava vina. Cilj ovog istraživanja bio je utvrditi utjecaj različitih načina jabučnomliječne fermentacije na kompatibilnost kvasca i bakterija, duljinu trajanja fermentacije, koncentraciju pojedinačnih organskih kiselina i spojeva arome te senzorna svojstva vina sorte ´Teran´ (Vitis vinifera L.). Pokus je obuhvaćao kontrolni tretman (bez JMF), spontanu JMF, induciranu JMF u početku alkoholne fermentacije (koinokulacija) te induciranu JMF po završenoj alkoholnoj fermentaciji. U svim tretmanima alkoholna fermentacija je u potpunosti završila, bez zastoja ili usporavanja. Koinokulacija je utjecala na značajno kraće trajanje JMF. Svi tretmani s JMF značajno su utjecali na sniženje koncentracije titracijske kiselosti i povećanje pH vrijednosti. Najviše koncentracije hlapive kiselosti i etil acetata utvrđene su u vinima spontane JMF. U svim tretmanima s JMF zabilježena je potpuna razgradnja jabučne kiseline te sniženje koncentracije limunske kiseline, ukupnih viših alkohola i acetaldehida. Nadalje, značajno više koncentracije etilnih estera, diacetila, acetoina i 2,3-butandiola zabilježene su u svim tretmanima s JMF.

The aim of this work was to study the influence of different vinification techniques on stilbenes and total polyphenolic content in red wines made from cv. Teran (Vitis vinifera L.). Four different vinification techniques were carried out: control (7 days maceration), prolonged maceration (10 and 21 days), and thermovinification. Four stilbenes were determined by high-performance liquid chromatography (HPLC), and total polyphenols were determined by spectrophotometric methods. The results showed the treatment of extended maceration (21 days) had a significant effect on the increase of total (35.74 mg/L) and individual stilbenes (trans-piceid, cis-piceid, trans-piceatannol, trans-resveratrol), as well as total polyphenols (2702.88 mg GAE/L). Treatment of thermovinification resulted in significant increase of the total polyphenolic content by nearly 20% in relation to control.

Cilj ovog istraživanja bio je utvrditi utjecaj duljine trajanja i temperature maceracije na koncentraciju slobodnih i ukupnih antocijana te parametre boje u vinima sorte ‘Teran’. Provedena su četiri različita vinifikacijska tretmana: 7 dana maceracije (TM7, kontrolni tretman), 10 dana (TM10) i 21 dan maceracije (TM21) pri temperaturi od 24°C, te 10 dana maceracije uz zagrijavanje masulja na 45°C prvih 48 sati (pred-fermentacijsko zagrijavanje masulja, TPHT). Koncentracija ukupnih i slobodnih antocijana, te intenzitet, nijansa i kompozicija boje određeni su spektrofotometrijski. Koncentracija ukupnih antocijana kretala se od 334, 3 mg/L do 444, 73 mg/L (TPHT, TM21), a slobodnih antocijana od 76, 73 mg/L do 113, 57 mg/L (TM10, TM21), tretman produljene maceracije (TM21) imao je značajan utjecaj na povećanje koncentracije ukupnih i slobodnih antocijana. Intenzitet boje kretao se u rasponu od 1, 59 do 1, 69 (TM10, TPHT), a nijansa boje od 0, 52 do 0, 54, pri čemu je kontrolni tretman imao signifikantno najnižu izmjerenu vrijednost nijanse boje. Unatoč nižoj koncentraciji slobodnih i ukupnih antocijana, kod pred-fermentacijskog tretmana zagrijavanja zabilježen je signifikantno najveći intenzitet boje, što je vjerojatno posljedica procesa kopigmentacije, odnosno tvorbe polimernih pigmenata. Iz dobivenih rezultata može se zaključiti da duljina trajanja i temperatura maceracije značajno utječu na sastav vina. Poduljena maceracija vodi ka povećanju koncentracije slobodnih i ukupnih antocijana, dok pred-fermentacijsko zagrijavanje utječe na povećanje intenziteta i stabilnosti boje, stoga oba tretmana mogu imati praktičnu primjenu u proizvodnji crnih vina.

BACKGROUND: Leaf removal is a viticultural practice that promotes the biosynthesis of several important grape constituents by improving fruit zone microclimate. The purpose of this study was to assess the effects of hand and mechanical leaf removal, applied at the pea‐size stage of berry development, on fruit zone microclimate, volatile aroma compounds, hydroxycinnamates and sensory characteristics of Istrian Malvasia (Vitis vinifera L.) wines. Three different sunlight exposure conditions were applied: hand leaf removal (HLR), mechanical leaf removal (MLR) and untreated control (UC). RESULTS: Both leaf removal treatments, and especially the more intense HLR, significantly increased the concentration of varietal thiol 3‐sulfanylhexan‐1‐ol, monoterpenes, β‐damascenone and esters. The higher concentration of these aromas contributed to the improvement of wine sensory quality, as expressed by more enhanced floral, fruity and tropical sensory attributes in leaf removal treatments. Hydroxycinnamates were increased only by HLR, a treatment with a greater degree of fruit exposure to sunlight than MLR. CONCLUSION: Leaf removal applied at the pea‐size stage of berry development in a season characterized by abundant rainfall improves both the chemical composition and sensory quality of Istrian Malvasia wine, even when performed by machine, implying that this technique might be successfully applied in large‐scale viticultural production.

Information on the content and composition of phenols in monovarietal wines is of fundamental importance for adequate wine quality management and control, it is useful for predicting wine sensory properties and oxidative stability, and may indicate wine age and production technology. It may also be used for authentication of varietal origin, as well as a strong point in marketing. To investigate the possibility of wine varietal differentiation based on phenol composition despite the existing heterogeneity, almost 200 samples produced from grapes of various red and white varieties grown in various terroirs in three Croatian regions were subjected to targeted profiling of phenols by ultra-performance liquid chromatography-triple quadrupole mass spectrometry. Descriptive sensory analysis was performed, including evaluation of varietal typicity, to investigate if there is a relation between variety-typical sensory profiles and certain phenols. Many of identified phenols were attributed as discriminators between wines. Plavac mali was characterized by the most distinguished anthocyanin profile, with generally the lowest concentrations among the investigated red wines. On the other hand, the wines from this variety were generally the most abundant in non- anthocyanin phenols. Cabernet Sauvignon wine stood out with the highest values of acetylated to p-coumaroylated anthocyanins ratio and the percentage of the sum of the acylated anthocyanins. Teran wine was characterised by the highest concentration of anthocyanins in general, while Merlot exhibited the least distinguished profile. As for white wines, those from the region of Dalmatia made from Pošip and Maraština varieties were generally more abundant in phenols than others. Malvazija istarska wines contained the lowest concentration of the majority of flavonols and hydroxycinammates, while Graševina was distinguished by the lowest amounts of flavan-3-ols. The highest concentrations of hydroxycinammates were found in Muscat blanc wines. Linear discriminant analysis resulted in successful differentiation, with peonidin 3-(6”- acetyl)-glucoside and taxifolin as the most potent differentiators among red, and cis-piceid among white wines. Particular varietal typicity concepts were partially confirmed by tentatively relating the concentrations of certain phenols and their possible sensory effects. This work has been supported by the UIP-2014-09- 1194 (Croatian Science Foundation) and ADP 2017 (Trento, Italy) projects.

In the past few decades a significant increase in the alcohol content of red wines in many regions of the world was observed: wines with high alcohol content became a frequent problem of oenology which is the indirect effect of global climate change. The increase in the daily average temperature and in the number of sunshine hours results in the advance in vine phenology and faster sugar production in berries, which culminates in higher sugar concentration in grapes. However, the formation of phenolic and aromatic components and changes in acidity profile is differently influenced by the temperature. In order to develop a viticulture technology which is adapted to the current challenges concerning the climate change, the aim of this study was to investigate the possibilities of adjusting vineyard canopy management practices to reduce the accumulation of sugar during the maturation phase without reducing the accumulation of secondary metabolites in grapes. Four factors which affect grape maturation and its final composition were investigated: the height of shoot trimming, crop level obtained by different number of shoots per vine, cluster thinning, and the date of harvest. The research was conducted on Merlot variety in two climatically different regions ; in Istria (Croatia), under the Mediterranean climate and in Eger (Hungary) under continental climate conditions. The investigated factors differently affected the accumulation of sugar and the secondary metabolites in grapes and wines, and the best growing practices to mitigate the effects on climate change were proposed.

Maturation of berries located in different portion of the cluster is not synchronized, thus potentially impacting fruit quality at harvest. Based on this assumption, an experimental trial was performed to evaluate the effect of selective cluster thinning on the phenolic maturation of Refosco dal peduncolo rosso grapes, an autochthonous variety grown in Friuli Venezia Giulia region (North-Eastern Italy). The trial was conducted in a vineyard of the Scarbolo farm, located Southern of Udine during two consecutive growing seasons. The experiment was carried out with a completely randomized block design with three treatments and 3 replicates of 12 vines each. The treatments were: UN, untreated control ; CT, Cluster Thinning (removal of entire cluster) ; WT, Wing and Tips thinning (removal of the cluster wings and tips in each cluster). All treatments were applied at full veraison and involved a similar reduction of fruits (about 40%). After the treatments, 2 sets of berries were randomly collected and used for basic fruit chemistry parameters and metabolites measurements, respectively. Skins and seeds were separated and grinded under liquid nitrogen, and anthocyanin profile (Sivilotti et al. 2016), skin and seed tannins (Herrera et al. 2015) and their structural characteristics (mDP, %G, %P) (Kennedy & Jones, 2001) were assessed. As expected, both CT ad WT thinning treatments increased soluble solids in grapes at harvest. Moreover, skin tannins were reduced, in particular in the WT treatment, while total anthocyanin concentration was significantly increased in both treatments. In detail, CT and WT treatments resulted in a significant increase of the proportion of hydroxylated and methoxylated forms of anthocyanins, and in a significant reduction of the proportion of the p-coumarated forms when compared with control. The effect of selective cluster thinning and the related changes in grapes composition are discussed, also with regard to a possible impact on wine properties.

Ampelotehnički zahvati reza u zeleno se redovito primjenjuju u vinogradarskoj proizvodnji budući da mogu u znatnoj mjeri utjecati na tijek dozrijevanja i sastav grožđa. Defolijacija kao mjera reza u zeleno ima poseban značaj u uvjetima visoke bujnosti, gdje zona grozda može biti u velikoj mjeri zasjenjena, dok se prorjeđivanje grozdova uobičajeno provodi kod sorata koje karakterizira visoka rodnost. Cilj ovog rada bio je istražiti utjecaj rane defolijacije i prorjeđivanja grozdova na komponente prinosa i sastav grožđa sorte Teran (Vitis vinifera L.) tijekom dvije godine u uvjetima Vinogorja Zapadna Istra. Oba istraživana tretmana utjecala su na smanjenje prinosa u odnosu na kontrolu, a to je smanjenje bilo izraženije kod prorjeđivanja grozdova. Kod oba istraživana tretmana dobiveno je značajno povećanje udjela šećera i ukupnih fenola u grožđu, dok je povećanje udjela antocijana u grožđu postignuto samo primjenom rane defolijacije. Unatoč većem prinosu i nižem omjeru lisne površine i mase grožđa u odnosu na prorjeđivanje grozdova, rana defolijacija je postigla veći udio antocijana i ukupnih fenola u grožđu, temeljem čega se može zaključiti kako je u svrhu povećanja kvalitete grožđa sorte Teran prikladnije primjenjivati ranu defolijaciju nego prorjeđivanje grozdova.

The aim of this study was to assess the impact of three different sunlight exposure conditions, obtained by hand and mechanical leaf removal at pea-size berry stage, on photosynthetic active radiation in the cluster zone, cluster temperature, on volatile aroma compounds, hydroxycinnamic acids and sensory characteristics of Istrian Malvasia (Vitis vinifera L.) wines. The exposure of clusters to photosynthetic active radiation was considerably increased by leaf removal, while only a mild effect on cluster temperature was obtained. The concentration of monoterpenes, β-damascenone, varietal thiol 3-sulfanylhexan-1-ol and esters in wines were significantly increased by both leaf removal treatments as compared to the non defoliated control, and especially by the more severe hand leaf removal. The differences in wine aromas were reflected on the improvement of wine sensory quality, and more intense positive odor notes, such as fruity, floral and tropical, as well as better aftertaste and overall quality, characterized wines obtained by leaf removal treatments. Hydroxycinnamic acids in wines were increased only by hand leaf removal treatment, which is characterized by increased cluster exposure to the sunlight compared to mechanical defoliation.

Due to the significance of grapevine as a crop plant and a cultural heritage, it is very desirable to understand the genetic and hybridization events which led to today’s cultivars development and distribution. The knowledge about pedigree can reveal its geographical origin and genetic composition and help to establish and understand cultivars migration routes and historical importance. Based upon previous research, it was expected that genitors of the most Croatian varieties were traditional local varieties. To examine their origin, all presumable Croatian varieties preserved in national grape collections were subjected to parentage reconstruction via microsatellite markers. This was carried out using 20 SSR markers common to INRA’s Vassal collection, and further 14 tri- and tetra- nucleotide SSR markers which served as further confirmation set. In addition, to dissect maternal origin, chlorotypes were defined also via cpSSR markers. Unlike presumed, in many cases one of the parents was a foreign variety - that is a genotype that was not recorded in any of the Croatian grape collections. This refers the most to Bombino bianco, high- yielding variety from Italian region Apuglia which turned out to be the mother of several Dalmatian varieties. It is also the case for nowadays in situ rarely found cultivars like Blank blauer (syn. Vulpea) and Alba imputotato. The reconstructed kinship group of Gouais blanc, consisting of varieties grown in northwestern part of Croatia, but also in Primorje and Istria (coastal area) gives support to the alternative hypothesis about its Pannonian origin.

Flavescence dorée (FD) is a vector-transmitted phytoplasma disease that causes important economic losses in European winegrowing regions and currently applied control strategies are only partially efficient. Practices applied in FD management were identified within Horizon 2020 WINETWORK project with the aim to contribute to a more efficient and environmentally responsive FD control. An interview survey was conducted in ten winegrowing regions within seven European countries. Interview questions were designed to collect winegrowers’ knowledge and innovative practices in FD management. At least 20 experienced winegrowers per region were selected and interviewed (in total 219 interviews), which had been selected according to their active participation in wine producing sector, good knowledge on FD, implementation of innovations and significant interest in disease management strategies. Collected data was analysed and practices that were recognized as useful were selected for further dissemination. Our findings indicate that timely and accurate vector monitoring is crucial to prevent spatial phytoplasma transmission and epidemic disease spread. In areas where FD is present, collective management, which includes both vector control and removal of phytoplasma-infected vines, efficiently limits or decreases disease spread. Innovative strategies identified were primarily oriented to biological vector control with natural compounds (clay, pyrethrum, orange essential oils and extracts), while no completely effective practice to control phytoplasma in grapevine or vector has been identified. Hot water treatment was identified as a potential measure for phytoplasma eradication in plant material in nurseries. It is concluded that large variation in overall FD knowledge between regions and implementation of practices with different efficiency rates may contribute to phytoplasma spread in new viticulture areas. It has been identified that producers efficiently recognize FD symptoms in a higher rate in regions with FD presence than in regions where phytoplasma has not yet been identified. Furthermore, in regions where FD is not present control strategies are not implemented in large scales, which could lead to rapid disease spread in case of phytoplasma introduction.

Grapevine trunk diseases (GTD) encompasses several fungal diseases and numerous fungal species, that induce wood deterioration and lead to reduced yield and grape quality, causing efficient application of control strategies challenging. The main objective of Horizon 2020 project WINETWORK was to identify and collect knowledge on common and innovative control practices that winegrowers have recognized as efficient in overall GTD management. In order to answer winegrowers’ needs on GTD management and collect information significant for scientific research a survey of 219 interviews was conducted, in the framework of project WINETWORK, in ten European winegrowing regions (within seven countries). The questionnaire was compiled of general questions related with viticultural production and GTD-specific questions. Our findings indicate that winegrowers in most cases adopt practices for GTD management after initial development of leaf symptoms or when increased disease distribution is observed in vineyard. Preventative disease management is oriented to either minimization of infection rates as a result of reduced number and size of pruning wounds present in innovative pruning systems or protection of pruning wounds with biological control agents and chemical fungicides. Reduction of negative disease impact is obtained with extirpation and replantation of symptomatic vines, trunk ‘cleaning’ and trunk renewal (remedial surgery). Control strategies in grapevine nurseries are oriented to disinfection of tools and soaking of grafted vines in fungicide solution. Singularly applied treatments for trunk pathogen control had resulted as low efficient, time-consuming or expensive. The survey has identified the level of winegrowers’ general knowledge on GTD that will contribute to more specific and end-users adapted dissemination activities. It is concluded that the actual disease management consolidates different practices that minimize the development of new infections and reduce fungal inoculum in vineyard, with the aim to avoid the negative impact of GTD on vineyard sustainability, yield and grape quality. Further research is needed in order to find highly effective measures against GTD.

Bolesti drva i zlatna žutica vinove loze se posljednjih godina sve više šire vinogradima diljem Europe, pritom dovodeći do odumiranja trsova, smanjenja dugovječnosti vinograda i značajnih ekonomskih šteta u proizvodnji. Projekt WINETWORK temelji se na suradnji europskih zemalja u svrhu razmjene i prijenosa inovativnog znanja između vinogradarskih regija te povećanja proizvodnosti i održivosti vinogradarsko-vinarskog sektora. Tijekom 3 godine, 11 partnera iz 7 europskih zemalja razmijenit će rezultate istraživanja i praktična iskustva na temu ovih značajnih bolesti vinove loze. Mreža suradnika na projektu poticat će interakciju između znanstvenika i proizvođača u svrhu identifikacije aktualnih problema koji se tiču ovih bolesti, prikupljanja i prijenosa znanja i iskustava različitih dionika europskih vinogradarskih regija te utvrđivanja najboljih rješenja u suzbijanju bolesti drva i zlatne žutice vinove loze. U projekt WINETWORK uključeno je oko 180 osoba u prikupljanju, obradi i širenju rezultata istraživanja i dobrih proizvodnih praksi. Projekt je financiran sredstvima Europske unije putem programa za istraživanja i inovacije Obzor 2020, ugovor broj 652601.

Flavescence dorée (FD) is a grapevine disease that spreads epidemically if not managed properly and implementation of control strategies is mandatory in most European winegrowing regions. Overall accepted strategies applied in FD management are based on vector monitoring, insecticide application and removal of infected vines and secondary hosts. Grapevine trunk diseases (GTD) involve a large number of xylem-inhabiting fungal species predominantly associated to botryosphaeria dieback, esca and eutypa dieback. Control strategies for GTD management are based on preventive techniques that minimize new infections. Both FD and GTD cause significant economic losses in European vineyards. Innovative practices and good management practices developed by scientists and winegrowers need to be disseminated and adapted to regular control strategies to maintain vineyard sustainability. Project WINETWORK is developing the innovation-driven methodology, which promotes the exchange of knowledge between science and practice. This network is implemented in ten winegrowing regions, within seven European countries. The methodology is built on a network of winegrowers and regional experts gathered in regional Technical Working Groups, Scientific Working Groups (one for each disease), and regional Facilitator Agents that stimulate their interaction. Bottom-up approach applied in WINETWORK includes surveys, conducted and synthesised by Facilitator Agents, to identify winegrower’s innovative practices, while scientists revise scientific data and adapt it to dissemination and practical use. Dissemination is adapted to different stakeholders and includes a summary of relevant practical and scientific knowledge available through the knowledge reservoir, newsletters, workshops, video clips, technical presentations, multimedia tools, etc. Overall objective of WINETWORK is to foster the exchange of scientific and practical knowledge to increase the productivity and sustainability of the sector and identify needs from the field and innovative solutions for future research agenda.

Grapevine trunk diseases (GTD) involve a large number of xylem-inhabiting fungal species mostly associated to botryosphaeria dieback, esca and eutypa dieback. Management of GTD is based on preventive control measures in order to minimize new infections and measures that reduce the existing fungal inoculum (vine removal, etc.). Flavescence dorée (FD) is a quarantine grapevine disease caused by a phytoplasma ‘Candidatus Phytoplasma vitis’ and spread by a Vitis specific vector, leafhopper Scaphoideus titanus Ball (Cicadellidae). Despite mandatory control measures FD is still a threat to the sustainability of European viticulture. Management of FD predominantly relies on the use of insecticides (vector control) and removal of infected vines and secondary hosts. Consequently, development of integrated approach in disease control is required. Both GTD and FD cause significant economic losses in European vineyards, referring to the necessity of finding alternative strategies to restrain their spread and negative impact on grape production. Project WINETWORK is developing the innovation-driven methodology based on multi-actor approach, which promotes the exchange of knowledge between science and practice in order to increase the productivity and sustainability of the sector and identify needs from the field and innovative solutions for future research agenda. This network is implemented in ten winegrowing regions, within seven European countries. The methodology is built on a network of winegrowers and regional experts gathered in ten regional Technical Working Groups, Scientific Working Groups (one for each disease), and regional Facilitator Agents that stimulate their interaction. Bottom-up approach applied in WINETWORK includes surveys, conducted and synthesised by Facilitator Agents, to identify winegrower’s innovative practices, while scientists revise scientific data and adapt it to dissemination and practical use. Dissemination is adapted to different stakeholders and includes a summary of relevant practical and scientific knowledge available through knowledge reservoir, newsletters, seminars, workshops, video lectures, technical presentations, etc. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No°652601.

Accelerated grape ripening with the ensuing high wine alcohol concentration has become widespread problem in various grape growing regions in the recent years. One possibility of adaptation to this emerging problem can be obtained by different canopy management practices in the vineyard. In this study the effects of severe shoot trimming and cluster thinning on grape ripening and grape and wine quality of cv. Teran were investigated, with the aim to find a canopy management practice which will result with lower wine alcohol concentration, without affecting the phenolic composition of grapes and resultant wines. In a Teran vineyard, two different shoot heights (70 and 130 cm), obtained by shoot trimming at the beginning of veraison, were combined with cluster thinning ; with cluster thinning applied at the beginning of veraison (CT) or without cluster thinning (NO CT). At earlier stages of ripening, higher differences in soluble solids among treatments were observed, with severe shoot trimming having larger impact than cluster thinning. With approaching to full maturity, the differences among treatments still remained, but were less pronounced than in earlier stages. The lowest alcohol, total anthocyanins and total phenolics concentrations in wines were achieved with 70 cm/NO CT treatment, while the highest values were achieved with 130/CT treatment. While 70/CT treatment had lower soluble solids in grapes and alcohol concentration in wine than 130/NO CT treatment, the opposite trend was observed with total anthocyanins in grapes and wines, which were higher in 70/CT than in 130/NO CT treatment, and in 70/CT treatment reached almost the same values as in 130/CT treatment. Both severe shoot trimming and cluster thinning can be effectively used in order to manipulate cv. Teran grape and wine quality, taking into account both the desired wine composition and the yield loss as a result of cluster thinning.

Nitrogen fertilization is a regular agricultural practice as it affects vine growth and yield as well as grape and must nitrogen content. It also has an impact on the fermentation rate. Common viticultural practice includes soil application. The aim of this study was to determine the effect of foliar application of three different nitrogen forms on grapevine nitrogen supply, indicated by leaf nitrogen status. Study was conducted on cv. Graševina (clone ISV-1) grafted on SO4 rootstock. It was carried out in 2012 and 2013 on Jazbina trial field of the Faculty of Agriculture in Zagreb (Zagreb winegrowing region) using latin square design. The trial consisted of five treatments: K (no fertilization), NPK (250 kg/ha winter soil application), Drin (NPK soil+foliar 0, 25% Drin), UR (NPK soil+foliar 1% urea) and AN (NPK soil+foliar 0, 25% ammonium nitrate). Foliar fertilization was repeated in four growth stages: 8 leaves separated, before flowering, berries pea-size and after harvest (according to modified E-L system). Prior to every treatment, leaf samples were taken and leaf total N was determined according to Kjeldahl method. Foliar N fertilization positively affected the leaf N status, but its effect depended on N form applied. The highest result was obtained by UR treatment, which significantly increased total leaf N compared to K and NPK treatment. Obtained results indicate positive effect of foliar N application in order to improve grapevine N supply.

Ocuvanje i revitalizacija izvornih sorti vinove loze, aktualna je tema u vinogradarskoj praksi.Publikacija sadrži pregled 125 izvornih i udomaćenih sorata vinove loze, njihove fotografije, opise, rasprostranjenost i klasifikaciju ugroženosti. Izradila ju je grupa autora, među kojima su vodeći domaći stručnjaci za problematiku izvornih i udomaćenih sorti vinove loze. Po prvi puta je za jednu skupinu udomaćenih vrsta izrađena klasifikacija ugroženosti prema modelu za divlje vrste. Također, publikacija daje sveobuhvatan prikaz porijekla, domestikacije i tradicijskog vinogradarstva u Hrvatskoj, kao i pregled regionalizacije vinogradarske proizvodnje i nadležne legislative te utjecaj vinogradarstva na očuvanje bioraznolikosti.

U radu se uspoređuju urodi Malvazije Istarske na trsovima sa 16 pupova (45714 /ha) i 32 pupa (91428 /ha), na podlogama 420A i Kober 5BB, na kordoncu kratkog reza, sa 1 ili 2 pupa po rezniku u 2014. godini. Dobiveni su visoki prinosi po trsu i hektaru, sa manjim sadržajem šećera, visokim kiselinama i dobrim pH. Statističkom obradom podataka utvrđene su razlike između varijanti pokusa u prinosima po trsu i hektaru, broju grozdova i djelomično koeficijentu rodnosti. Razlike nisu utvrđene kod mase grozda, te sadržaju šećera, kiselina i pH u moštu. Iako su istraživani tretmani značajno utjecali na broj grozdova, te prinos po trsu i prinos po hektaru kod obje podloge (420A i K5BB), sastav mošta se nije značajno razlikovao među tretmanima.