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Grapevine-downy mildew interaction is one the most challenging biotic stresses. In order to avoid undesirable features of non-vinifera species, usually used for resistance breeding, the resistance of cultivated (V. vinifera) varieties to the main diseases is in the spotlight again. Aiming to find differences among Croatian native grapevine varieties in susceptibility to downy mildew, whose causal agent is Plasmopara viticola, an experiment has been conducted. Young leaves of 14 Croatian native grapevine varieties, together with Chardonnay (susceptible control variety), Solaris (partially resistant variety) and Vitis riparia (resistant genotype) were sampled and used in this research. A leaf disc bioassay was applied according to the OIV descriptor 452-1 whereby the genotypes were ascribed to corresponding OIV classes 1, 3, 5, 7, and 9 from the most susceptible to the totally resistant ones. Polyphenolic compounds were quantified by high-performance liquid chromatography (HPLC). The results were analysed using one way ANOVA and the differences between the means were evaluated by Duncan’s multiple range test at a confidence level of 95 % (p < 0.05). Principal component analysis was performed to show the differences in the polyphenolic composition of grapevine leaves between non-inoculated and inoculated varieties belonging to OIV classes 1, 3 and 5 in different terms (24, 48 and 96 hpi) upon inoculation. Majority of evaluated native varieties (≈80 %) are highly susceptible or susceptible to P. viticola belonging to OIV classes 1 or 3, respectively. However, scarce sporulation (21-40 %) developed on leaf discs of the following varieties Malvazija istarska, Ranfol and Teran placed them to the OIV class 5. PCA clearly distinguished diverse classes of susceptibility among evaluated V. vinifera varieties based on their polyphenolic composition. Nonetheless, their polyphenolic composition in terms upon inoculation was not significantly different. Methods applied in this research proved to be reliable and complement one to another. Early changes in polyphenolic profiles upon inoculation were not found, although they served as a decisive feature for distinguishing classes of susceptibility which were previously obtained by artificial inoculation. Less susceptible grapevine varieties that belong to the class 5 could be of interest to use in breeding programs.

Graševina je gospodarski najvažnija i najraširenija bijela sorta vinove loze u Republici Hrvatskoj. Pored svih vrijednih spojeva, vino sadrži i teške metale koji u povišenoj koncentraciji mogu utjecati na kvalitetu vina. Njihov sadržaj u grožđu i vinu ovisi o sorti, klimi, tlu te primjeni poljoprivredne prakse u vinogradu i tehnoloških procesa u proizvodnji. Istraživanjem je analizirano 10 vina berbe 2017 godine sorte 'Graševina' iz vinogradarske podregije Hrvatsko Podunavlje (vinogorje Baranja, Srijem i Erdut). ICP-MS i ICP-OES metodama određene su koncentracije teških metala. Rezultati pokazuju da sva analizirana vina udovoljavaju propisanim standardima Pravilnika o proizvodnji vina.

Grožđe sorte ´Babić´ s položaja Jadrtovac u vinogorju Šibenik, korišteno je u istraživanju utjecaja različitih vrsta i sojeva Saccharomyces i ne-Saccharomyces sp. (Lachancea thermotolerans i Torulaspora delbrueckii) kvasaca, nakon čega su uspoređeni sastav i svojstva proizvedenih vina. Osnovna fizikalno- kemijska analiza provedena je prema metodama O.I.V.-a, pojedinačne organske kiseline i ukupni fenolni spojevi analizirani su spektrofotometrijski, a pojedinačni fenolni spojevi uz pomoć tekućinske kromatografije visoke djelotvornosti (HPLC). Utvrđene su značajne razlike u koncentracijama svih osnovnih parametara, s posebnim naglaskom na pojedinačne organske kiseline, ukupnu kiselost i ukupne fenole.

Sorte vinove loze (Vitis vinifera L.) osjetljive su na plamenjaču, no ipak postoje razlike u razini njihove osjetljivosti na navedenu bolest. U svrhu određivanja razina osjetljivosti unutar bogate hrvatske germplazme vinove loze, provedeno je istraživanje tijekom 2018. i 2019. godine. Reznice 50 genotipova (46 autohtonih sorata te 'Cabernet sauvignon' i 'Rizling rajnski' kao osjetljive kontrole, a 'Solaris' i Vitis riparia kao otporne kontrole) posađene su u posude i uzgajane na vlastitom korijenu u poljskim uvjetima. Praćenje simptoma bolesti započelo je kad su mladice bile u stadiju od 10 razvijenih listova. Evaluacija pomoću modificiranog OIV deskriptora 452 (razina otpornosti listova) provedena je u četiri termina u dvotjednim intervalima tijekom svake vegetacije. Genotipovi su razvrstani u kvartile prema postotku listova sa simptomima bolesti. Genotip, termin evaluacije, kao i interakcija navedena dva faktora statistički se značajno razlikuju tijekom obje godine evaluacije. Iako su gotovo sve autohtone sorte postale potpuno zaražene do kraja vegetacije, kod nekih, kao što su 'Malvazija istarska', 'Teran', 'Trojišćina', 'Ranfol', bolest je sporije napredovala. Naredna istraživanja provodit će se s ciljem definiranja mogućih reakcija na kemijskoj razini koje su odgovorne za obrambeni mehanizam kod različitih genotipova.

'Belina starohrvatska’ je sorta koja se projektom revitalizacije autohtonih sorata vraća u proizvodne nasade Hrvatskog zagorja. Kako bi se omogućio komercijalni uzgoj potrebno je definirati ampelotehničke zahvate koji će osigurati kvalitetu grožđa. Cilj ovog istraživanja je bio utvrditi tijekom dvije godine utjecaj djelomične defolijacije na prinos i kvalitetu grožđa ove sorte. Rana defolijacija je provedena u dva termina: neposredno prije cvatnje i neposredno poslije cvatnje. Tretmani defolijacije u prvoj godini nisu značajno utjecali na kemijski sastav grožđa dok je tretman defolijacije prije cvatnje rezultirao nešto većim prinosom. Međutim kod kontrolne varijante došlo je do potpune zaraze grožđa sivom plijesni. U drugoj godini ponovljena je usporedba dvije varijante defolijacije, sa istim rezultatima, te je uz njih provedena i redukcija cvatova, koja također nije značajno utjecala na kemijske parametre grožđa.

Zlatarica vrgorska i Trnjak hrvatske su autohtone sorte koje se uzgajaju u podregiji Dalmatinska Zagora, posebice u vinogorjima Vrgorac i Imotski. Klonska selekcija spomenutih sorata započela je 2018. godine provedbom masovne pozitivne i sanitarne selekcije. Selekcija je provedena na deset lokacija unutar vinogorja Vrgorac te je izdvojeno 97 klonskih kandidata sorte Zlatarica vrgorska i 27 sorte Trnjak. Odabrani su pozitivni mutanti bez vizualnih simptoma zaraženosti virusima. Bazalni uzorci rozgve uzeti su 2019. godine tijekom zime sa svakog pojedinačno odabranog matičnog trsa. Prikupljeni uzorci testirani su na prisustvo četiri gospodarski najvažnija virusa serološkom metodom ELISA (enzyme linked immunosorbent assay): virus lepazatsog lista vinove loze (GFLV), virus mozaika vinove loze (ArMV), virusi uvijenosti lišća vinove loze 1 i 3 (GLRaV-1 i GLRaV-3). Prema dobivenim rezultatima, u pet uzoraka sorte Zlatarica vrgorska i 6 Trnjka crnog nije utvrđena prisutnost analiziranih virusa. Najrašireniji virus GLRaV-3 pronađen je u 69, 07 % biljaka kod sorte Zlatarica vrgorska te u 37, 04 % kod sorte Trnjak. Slijedi ga virus GLRaV-1 koji je prisutan u 55, 67 % biljaka sorte Zlatarica vrgorska i 62, 96 % sorte Trnjak. Prisustvo drugih virusa je značajno rjeđe pa tako nalazimo GFLV u 11, 34 % uzorka sorte Zlatarica vrgorska i u 37, 04 % sorte Trnjak. Virus ArMV nije pronađen u populaciji sorte Trnjak, dok je kod Zlatarice vrgorske pronađen u 13, 4 % analiziranih uzoraka.

Fenolni spojevi predstavljaju sekundarne biljne metabolite koji imaju vrlo važnu fiziološku i morfološku ulogu u rastu i reprodukciji biljke pružajući joj i zaštitu protiv patogena i predatora. Cilj ovoga istraživanja je dobiti pregled promjena u sastavu i sadržaju fenolnih spojeva odnosno flavonola, flavanola, hidroksicimetnih i hidroksibenzojevih kiselina prisutnih u listovima četiri različite crne sorte vinove loze. Ekstrakti su analizirani tekućinskom kromatografijom visoke djelotvornosti. Dobivenim rezultatima utvrđena je značajna varijabilnost u masenim udjelima fenolnih spojeva između sorata po pojedinim terminima uzorkovanja, kao i značajna varijabilnost u sadržaju fenolnih spojeva unutar iste sorte tijekom različitih termina uzorkovanja.

Zlatarica vrgorska je hrvatska autohtona sorta koja se uzgaja na području vinogorja Vrgorac i Neretva. Klonska selekcija Zlatarice vrgorske počela je 2018. godine provedbom masovne pozitivne selekcije na području vinogorja Vrgorac. Masovna pozitivna selekcija je provedena na 10 lokacija unutar vinogorja te su ukupno izdvojena 124 matična trsa. Masovna pozitivna selekcija obuhvatila je vizualnu ocjenu zdrastvenog stanja i ampelografsku evaluaciju (morfološke, fenološke i gospodarske kakakteristike). Na svakom matičnom trsu utvrđeni su broj grozdova i prirod (kg/trs) te osnovni kemijski pokazatelji kakvoće mošta (sadržaj šećera, ukupna kiselost, pH vrijednost). Srednje vrijednosti za sadržaj šećera u moštu kretale su se od 43, 67 do 96, 67 0Oe, dok je interval sadržaja ukupne kiselosti iznosio od 2, 75 do 7, 25 g/l. Raspon srednjih vrijednosti pH vrijednosti mošta iznosio je od 3, 2 do 3, 78. Utvrđene srednje vrijednosti priroda matičnih trsova kretale su se u rasponu od 0, 18 do 17, 98 kg/trs, a raspon srednjih vrijednosti broja grozdova po trsu je iznosio od 2 do 53 grozda. Rezultati su pokazali značajnu varijabilnost utvrđenih kvantitavnih i kvalitativnih svojstava. Spomenuto ukazuje na značajnu unutarsortnu varijabilnost populacije sorte Zlatarica vrgorska što je iznimno važno za nastavak postupka selekcije zdravstvenom i individualnom klonskom selekcijom.

Cultivar Moslavac is considered as Croatian native cultivar. Because of its thin skin, soft berries and high vigour, the cultivar is susceptible to Botrytis, thus it should be planted on suitable vineyard sites and the canopy management operations should be used to control yield and vine microclimate. The aim of this work is to determine the effect of canopy management operations, early defoliation and grape thinning, on grape quality of cultivar Moslavac. The research was conducted in experimental vineyard in Sveti Urban (region Zagorje- Međimurje) with two treatments, control with none canopy management operations conducted and treatment with conducted early defoliation and grape thinning. Both operations were carried out at the same time, just after flowering. The defoliation was carried out removing all leaves in the fruiting zone, while grape thinning was carried out leaving just one grape bunch per shoot. After vérasion the ripening was monitored by measuring content of sugar and total acidity, while in full ripeness the yield and organic acids were determined. The higher content of sugars was determined at the treatment with early defoliation and grape thinning. Furthermore, the mentioned treatment did not show symptoms of Botrytis. There was no significant difference between treatments considering total acidity and the content of organic acids. It can be concluded that early defoliation and grape thinning had the greatest impact on sugar accumulation and very small impact on total acidity.

Numerous grapevine breeding programs are carried out in the world with the aim of getting varieties resistant to fungal diseases. The basics are often native varieties in order to preserve the authenticity of a certain area. Croatia counts more than a hundred native varieties but there is no research on their downy mildew susceptibility, which is essential for further breeding. The aim of this study is to compare the two most widely used methods for estimating the susceptibility of grapevine varieties: in vivo (field trial) and in vitro using the leaf disk assay. The research was conducted on nine genotypes: seven native varieties, Cabernet Sauvignon and Vitis riparia. In vivo disease symptoms were monitored after flowering four times in two-week intervals, and the leaf disks were evaluated once on the leaves of different developmental stages (from the 1st to 7th leaf from the shoot tip). Significant differences in susceptibility between the examined genotypes were found using both methods. By using the in vivo method significant differences were noticed during the initial terms, while the differences were reduced later on suggesting that the rate of disease development is peculiar to the genotype. In vitro method showed, together with differences between the genotypes, significant differences between the leaves of different developmental stages. The highest level of correlation between the results of these two methods (r>0, 5) was determined between the third term in vivo and the 3rd to the 6th leaf (from the shoot tip) in in vitro conditions.

Sve veći značaj ekološke poljoprivredne proizvodnje i potreba smanjenja upotrebe pesticida polako postaje trend i u vinogradarskoj proizvodnji. U najrazvijenijim europskim vinogradarskim zemljama sorte vinove loze selekcionirane na otpornost na gljivične bolesti dobivaju na važnosti. Na Agronomskom fakultetu Sveučilišta u Zagrebu od 2005 do 2015.-te godine na Zavodu za Vinogradarstvo i vinarstvo provodila su se sustavna višegodišnja praćenja gospodarskih svojstava dvadesetak registriranih sorata tolerantnih na bolesti. Najbolje gospodarske pokazatelje u većini karakteristika kod bijelih sorata imala je sorta Bianca. Od ostalih sorata vrlo dobre otpornosti i dobrih gospodarskih svojstava svakako valja izdvojiti Panoniju, sortu selekcioniranu na vinogradarskom pokušalištu u Sremskim Karlovcima i sortu Johanniter selekcioniranu u vinogradarskom institutu u Freiburgu u Njemačkoj. Od crnih sorata najbolju kvalitetu vina imala je sorta Cabernet Cortis.

Na području Ozaljsko-vivodinskog vinogorja nalazi se očuvan veliki broj vinograda starijih pedeset pa i 100 godina. Sustavna identifikacija sortimenta toga područja nije nikada rađena a povijesnih zapisa nema. Cilja istraživanja bio je ampelografskim i genetičkim metodama utvrditi sortiment i pronaći unikatne genotipove i sorte na tome području. Od 61. uzorka za DNA analizu utvrđeno je 45 različitih genotipova. Od toga broja čak 18 unikatnih genotipova prisutnih samo na ovom području.

Context and purpose of the study – Croatia has rich grapevine genetic resources with more than 125 autochthonous varieties preserved. Coastal region of Croatia, Dalmatia, is well known for wine production based on autochthonous grapevine varieties. Nevertheless, only couple of these are widely cultivated and have greater economic importance. Grape seeds are sources of polyphenols which play an important role in organoleptic and nutritional value of grape and wine. Hence, the aim of this study was to evaluate the simple polyphenols from grape seeds in 20 rare autochthonous grapevine varieties. Material and methods – Samples were collected during two consecutive years (2011. and 2012.) from germplasm collection in Split (Dalmatia). Grape samples were constituted of five bunches of fully ripe grapes. Seeds were manually separated, freeze-dried, grounded and stored at a low temperature until analyses. Polyphenolic compounds were analysed using HPLC analysis. Results – Eight polyphenolic compounds, galic acid, monomeric flavan-3-ols (catechin, epicatechin, gallocatechin and epicatechin 3-O-gallate) and procyanidin dimers (B1, B2 and B4) were detected. According to the investigated polyphenolic compounds significant differences between investigated varieties were found. Gallic acid content ranged from 91.0 to 245.08 total monomeric flavan-3-ols from 619.2 to 13539.6 mg kg-1 and total procyanidin dimers from 975.3 to 4140.2 mg kg-1 of seed. Catechin (263.2 to 8124.2 mg kg-1 seed) was found as main monomeric flavan-3-ol, epicatechin 3-O-gallate, gallocatchin and epicatechin varied between 0-164.31, 37.19-155.07 and 277.5-5224.4 mg kg-1 seed, respectively. Procyanidin B2 (420.2 to 2207.8 mg kg-1 seed) was found as a main procyanidin dimer. Procyanidin B1 and B4 amount varied between 401.80-165.19 and 276, 7-1539.4 mg kg-1 seed, respectively. Gegić had lowest and varieties Plavac mali and Babić highest amount of all investigated polyphenolic compounds. This study presents the first evaluation of Croatian grapevine varieties by characterization of seed polyphenolic compounds and it shows huge variability among them. More detailed analysis of polyphenolic compounds in selected varieties are carry out in our further research activities.

Numerous volatile compounds of grape berries play a major role in the aroma of the future wine. Despite the significant effect of different environmental conditions and management practices, grapevine cultivar has a dominant impact on content and composition of volatile compounds in white wines. The significant attention given to the local grapevine cultivars could present a new wine market trend which would help their promotion and revitalization. Since wine aroma largely affects the quality and value of white wines it is necessary to perform detailed aromatic characterisation of neglected cultivars before the final assessment of their potential for modern wine production. So far, 125 autochotonous grapevine cultivars were found in Croatia. Dalmatia, the costal part of Croatia, is especially rich in autochthonous grapevine cultivars. However, only a couple of these have a greater economic value. The aim of this study was to evaluate the volatile compounds in 24 rare white autochthonous grapevine cultivars for the first time. The volatile compounds represented by monoterpenes, norisoprenoids and C6-compounds were detected and quantified using GC-MS method. According to the investigated compounds, highest content of monoterpenes was determined in cvs. Silbijanac (27, 59 µg/kg), Prc (22, 63 µg/kg) and Gegic (21, 30 µg/kg) compared to the other investigated varieties. The content of the norisoprenoids analyzed was higher in Silbijanac (1, 1µg/kg), Trisnjavac (0, 99 µg/kg) and Marastina (0, 95 µg/kg) than in other varieties investigated. The highest content of C6-compounds was detected in Malvasija dubrovacka (32, 38 µg/kg) and Marastina (22, 53 µg/kg). Based on these results, most varieties showed good potential for white wine production. This study presents a step-in characterization of Croatian autochthonous grapevine varieties. However, these results showed that these rare varieties can become a good alternative to the most prevalent grapevine varieties used in Croatia.

In spite of being a small country, Croatia presents an important source of grapevine biodiversity which can be interesting for wine industry and breeding. In last two decades our research activities are focused on preservation, genotyping and evaluation of production characteristics of native varieties. To define full potential of native varieties there is a need to define the level of their susceptibility to fungal diseases. The aim of this research was to define the level of susceptibility/resistance of Croatian grapevine varieties to downey mildew (Plasmopara viticola) using modified field screening method. Altogether 57 genotypes/varieties were included in the research: 52 Croatian native varieties, two susceptible international V. vinifera L. cultivars (Cabernet Sauvignon, Riesling), 2 resistant cultivars (Solaris, Regent) and 2 Vitis species (Vitis ripara, Vitis amurensis). Own-rooted cuttings were planted in drip irrigated pots in field conditions close to the production vineyard at experimental station “Jazbina”, Department of Viticulture and Enology, Faculty of Agriculture Zagreb. After initial growing of shoots to the certain stage the monitoring of disease symptoms was carried out according to OIV descriptor 452 (degree of resistance on leaves). Results showed small difference among native varieties and majority of them have very low and low level of resistance to downy mildew, as expected.

Vinova loza jedna je od poljoprivrednih kultura na kojoj je utvrđena zaraza velikim brojem virusa. Da bi se pristupilo biotehnološkim postupcima ozdravljivanja od virusa (kultura meristema, termoterapija, krioterapija, potrebno je materijal uvesti u kulturu in vitro, a zatim ga multiplicirati kako bi se dobila dovoljna količina na kojoj bi se provelo ozdravljivanje. Poznato je da sorte vinove loze različito reagiraju na sastav hranjive podloge i da virusna zaraza uvelike utječe na preživljavanje i regeneraciju u in vitro uvjetima, te na daljnje manipulacije istima. Cilj ovog rada je utvrditi razlike među sortama korištenim u istraživanju (Cabernet franc, Cabernet sauvignon, Grenache, Merlot, Babić) zaraženih različitim virusima u in vitro kulturi, te usporediti preživljavanje i regeneraciju sa kontrolnom sortom Portan, nakon provedenog potencijalnog postupka ozdravljivanja smrzavanjem krioprezervacije. Pojedine sorte nisu preživjele niti u in vitro kulturi, a samo na jednoj sorti je provedena krioprezervacija. Postotak preživljavanja je bio podjednak kod nesmrzavanih eksplantata, dok su smrznuti eksplantati dali znatno lošije rezultate. Smrznuti eksplantati su jako loše regenerirali, što upućuje na potrebu za daljnim definiranjem protokola in vitro kulture i krioprezervacije za takav tip zaraženog materijala.

Biosynthesis of anthocyanins is one of the most important biochemical processes, which occur during the growth and development of grape of red cultivars. Anthocyanins are water-soluble pigments present in the vacuoles of the skin cells responsible for the red colour of berry and wines. Increased sunlight exposure enhances the biosynthesis of flavonoids especially anthocyanins during grape ripening. Different timing of partial fruit zone leaf removal can have significant effect on dynamics and total content of anthocyanins in grape. Cv. Merlot was introduced in North Dalmatia by the end of 20th century. This area is characterised by Mediterranean climate, but grapes from some sites with deep fertile soils can result in low level of grape anthocyanins. The aim of this research was to identify the effect of two different timing of fruit zone leaf removal performed (1) during flowering and (2) during veraison on dynamics of anthocyanins accumulation in grapes of Merlot cultivar in comparison to undefoliated control. Berries samples were collected every 10 days starting from veraison to full maturity. Identification and quantification of anthocyanins were conducted by HPLC method. The total anthocyanin content (TAC) ranged from 60.90 to 192.62 mg/100 g berries and from 52.02 to 183.39 mg/100 g berries at the flowering and veraison defoliation, respectively. In control samples TA ranged from 35.12 to 215.14 mg/100 g. The statistical analysis showed that different defoliation time had significant impact on the anthocyanin concentrations of ‘Merlot’ cultivar grown in North Dalmatia.

Graševina je najvažnija sorta vinove loze u Hrvatskoj sa udjelom od 23% u ukupnim površinama pod vinogradima, u proizvodnim nasadima je najčešće cijepljena na dvije podloge Kober 5BB i SO4. Cilj ovog rada bio je utvrditi postojanje razlika u sadržaju organskih kiselina uvjetovanih utjecajem lozne podloge. Organske kiseline direktno utječu na fizikalnu, biokemijsku i mikrobiološku stabilnost vina, kao i na senzorna svojstva vina. Istraživanje je provedeno u pokusnom nasadu klonskih kandidata cv. Graševina izdvojenih u kutjevačkom vinogorju u postupku individualne klonske selekcije cijepljenih na dvije podloge Kober 5BB i SO4 kroz dvije godine berbe 2015. i 2016. Analiziran je sadržaj tri najvažnije organske kiseline u grožđu: vinske, jabučne i limunske spektrofotometrijskim metodama. U 2015. godini koja je bila izuzetno sušna nisu utvrđene signifikantne razlike između sadržaja organskih kiselina na dvije promatrane podloge. U 2016. godini sa prosječnim vremenskim uvjetima utvrđen je signifikantno viši sadržaj jabučne kiseline na podlozi Kober 5BB.

Introduction: Grapevine (Vitis vinifera L.) varieties are susceptible to fungal diseases like powdery mildew (Uncinula necator) and downy mildew (Plasmopara viticola) which are responsible for huge amount of pesticides used in grape production. Climatic conditions in Croatia are suitable for the development of fungal diseases, and that issue is even more severe in the northwestern part. Fungus resistant varieties are currently the only alternative for significant reduction of pesticides used in viticulture production. In order for them to become used for modern wine production, it is necessary to evaluate resistant varieties in different production conditions. Aim: The aim of this paper is to present the results of experiment conducted on twelve fungus resistant grape varieties in the conditions of the northwestern part of Croatia. Materials and methods: The varieties included in this experiment are Merzling, Phoenix, Staufer, Johanniter, Solaris, Regent, Cabernet Cortis, Bianca, Leon Millot, Monarch, Marechal Foch and Chancellor. As far as methods are concerned, the yield quality was determined by analyzing the chemical composition of must which includes the concentration of soluble solids and total acidity. The level of susceptibility to fungal diseases for each variety was determined. The microvinification and wine sensory analyses were performed. Secial focus was given to methyl alcohol content in the produced wines, organic acids composition of grape juice and polyphenolic composition of the berry skin and wine from red grape varieties. Results: The given results showed the level of susceptibility to fungal diseases comparable to other authors. The significant differences among investigated cultivars were noticed in all quality parameters evaluated. Based on these results, the resistant varieties Merzling, Phoenix, Staufer, Johanniter, Solaris, Regent and Cabernet Cortis were added to the list of recommended cultivars for wine production in the wine region West continental Croatia. Conclusion: All parameters determined among all the varieties in this experiment showed that some of them can be considered as a wine variety and become recommended in the northwestern part of Croatia. Even though most of varieties are not completely resistant to the fungal diseases in the given conditions, the application of fungicides could be reduced to minimum. They are specially interesting for organic wine production in this area.

Introduction: Croatia has very long viticultural history and more than 120 native grapevine cultivars. Among them there are cultivars that showed very good viticultural and enological potential, thus being in production for a long time. Due to the lack of clonal and sanitary selection in past, native cultivars in Croatia are having high level of intravarietal variability and virus infections. Modern viticulture requires stabile and uniform production characteristics and virus free planting material which can only be obtained through process of clonal selection. The clonal selection in Croatia started with cv. Škrlet in 2000 and was continued on other most important native cultivars from different wine regions. Currently, 12 cultivars are under the selection. Aim: The aim of this paper is to present the results of clonal selection in Croatia which was focused on improvement of productional characteristics of native grapevine cultivar, improvement of planting material quality and sanitary status. Materials and methods: The cultivars included in clonal selection are: Škrlet, Moslavac, Kraljevina, Graševina, Plavac mali, Maraština, Grk, Debit, Plavina, Pošip, Vugava and Žlahtina. The clonal selection was divided into three stages: 1) selection of initial material from old vineyards and virus testing (using ELISA) ; 2) establishment of experimental sites of vegetative progeny of virus free mother plants which were located depending on cultivar production region 3) final evaluation and registration of selected clones. Evaluation of clonal lines in stage two included evaluation of: yield level, cluster characteristics (compactness, mechanical composition, size and weight), chemical composition of must, vigor and susceptibility to pests. During final evaluation of selected clones in stage three, additional micorvinifications was performed including wine chemical and sensory analyses. Selected clones have also undergone analysis of grape aromatics (white cultivars) and polyphenols (red cultivars). Results: High level of intravarietal variability within populations of native cultivars allowed us to select sufficient number of virus free divergent clone candidates in first stage of selection despite the high level of virus infection detected. Vegetative progenies of all virus free mother vines were planted in second phase of selection, to preserve intravarietal variability for potential selection of new clones in future. Considering the importance of specific varieties, as well as divergency detected during process we decided to register different number of clones per variety: Plavac mali 5, Plavina 4, Pošip 4, Graševina 4, Kraljevina 4, Maraština 3, Škrlet 3, Vugava 2 and Debit 1. Three clones of cv. Škrlet are already registered while registration of others is planned during this year. Conclusion: The introduction of new clones will contribute to a sustainable grape and wine production, which can ensure better quality of wine. Moreover, it will contribute to production sustainability of native grapevine varieties in Croatia.

Much of the data acquired during the last few decades suggest that climate changes are taking place. These climate changes, in particular increasing temperatures, have important consequences on viticulture and different approaches have been proposed for adaptation. Shifting of grape varieties growth from their traditional sites towards a cooler climate is one of them. In Croatia, there are 125 autochthonous grape varieties including 38 red ones. The great majority of red grape varieties are native to the Costal Croatia region, belonging to the wine growing zone CII and mediterranean climate. The aim of this study was to investigate the content and composition of individual polyphenolic compounds of 11 Dalmatian varieties which were grown in Zone B with continental climate. Since Merlot is used in continental climate for production of high quality red wines, it was used for comparison. Out of 11 cultivars included in this research, highest skin content (based on dry weight) of anthocyanins was determined for ‘Nincusa (63068 mg/kg)’, ‘Trnjak’ (29716 mg/kg), ‘Dobricic’ (24464 mg/kg), ‘Ljutun’ (23695 mg/kg). The content of anthocyanins of ‘Plavac mali’, (cv. with very late ripening) was lower (18740 mg/kg) but almost the same as that of ‘Merlot’ (19334 mg/kg). A similar trend was observed in the case of flavonol-glycosides. The content of flavan-3-ols determined in varieties ‘Nincusa’ and ‘Rudezusa’ was lower than that observed in ‘Merlot’, while the values obtained for ‘Plavac mali’, ‘Dobricic’ and ‘Ljutun’ were higher than for ‘Merlot’. These results suggest that these varieties, based on the content and composition of polyphenolic compounds, have a potential for usage in continental climate wine production.

Chimeras are plants that contain tissues of at least two genotypes in different cell layers, as well as in organs resulting from these layers. Many grapevine cultivars and clones important for viticulture production today are periclinal chimeras which evolved spontaneously because of the mutations in one layer of apical meristem (Pinot gris, Pinot meunier etc.). In comparison with chimeras that have evolved from mutations, there are also so-called intra- and interspecific chimeras, which consist from two different genotypes originating from different cultivars or species. Synthetic chimeras could have huge potential as an alternative breeding method for grapevine since it is vegetatively propagated, but also to investigate cell autonomous vs non-cell autonomous developmental programs and track the movement of non-cell autonomous molecular information. Research on the possible development and detection of synthetic chimeras was conducted using three different grapevine cultivars: Cabernet sauvignon (CS), Chardonnay (C) and Babić (B) using meristematic bulk tissue (MBT) culture. First, conditions for successful MBT development and organogenesis were determined for individual cultivars. After this, organogenesis was induced from mixed MBT developed after contact growth of two pairs of genotypes (CSxC i CSxB), and in this way 260 plants were obtained and acclimatized. After visual evaluation of all plants, seven of them showed some level of tissue (leaves) heterogeneity, while others had a uniform phenotype. All plants were analysed using microsatellite (SSR) markers for grapevine and results for 8 plants suggest that they could be composed of 2 different genotypes, ie. chimeras. Research on stability and type of chimerism in vegetatively propagated chimeras’ progeny is in progress, using combination of phenotyping and genotyping.

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.

Evaluation of differences in yield and quality of grapevine is often based on the random samples of berries harvested on the same date. Due to differences in ripeness of berries from the same cluster, and among berries from different clusters of the same vine, the determined differences among examined treatments (clones, agricultural practices etc.) based on random berry samples may be over- or underestimated. The aims of this study were to determine: (1) differences among three 'Plavac mali' clones in the proportion of berries of different density classes (sugar concentration level) using the flotation method; (2) differences in berry weight and chemical composition among density classes of the same clone, and (3) differences between clones of the same density class. Significant differences were determined for all observed characteristics, among different berries density classes and clones. The results obtained indicate that berry samples used to compare different clones should be, to the greatest possible extent, at the same level of ripeness, as this significantly effects chemical composition. This can be achieved using the density separation of berries with the simple flotation method presented in this study. The presented results could be useful in the future improvement of clonal selection methodology as well as in improvement of sampling strategy for other types of researches., VITIS - Journal of Grapevine Research, Vol 56 No 3 (2017): Vitis

Trenutno jedan od najznačajnijih patogena vinove loze u Europi je fitoplazma koja uzrokuje bolest poznatu pod nazivom zlatna žutica vinove loze („Flavescence dorée“). Prenosi se zaraženim sadnim materijalom i američkim cvrčkom (Scaphoideus titanus). U zadnjem velikom valu sadnje novih vinograda (2004.-2010.) u Hrvatskoj korišten je sadni materijal nedovoljno siguran po pitanju zaražnenosti fitoplamom. U navedenom razdoblju podignuta je polovica današnjih vinogradarskih površina. Od prvotne potvrde prisutnosti zlatne žutice i njezinog vektora u Hrvatskoj bolest se znatno proširila, te je u pojedinim područjima poprimila epidemijske razmjere, izazvala značajne ekonomske štete i zabrinutost proizvođača. U radu je detaljnije opisan uzročnik bolesti zlatne žutice vinove loze, njezin vektor, širenje zaraze na području Hrvatske, mogući uzroci trenutnog stanja te prijedlog mjera za usporavanje i sprečavanje širenja.

Viticulture in Dalmatia (Croatia) is based on cultivation of native grapevine cultivars. Babic is one of the most important native red cultivars grown in central Dalmatia. It is traditionally grown without irrigation. New vineyards in this area are often established on fields obtained by karst reclamation where water deficit represents one of the major obstacles for sustainable grape production. The effect of two·different levels of deficit irrigation (Tl- 50% and T2- 75% of total evapotranspiration), normal irrigation (T3- 100% of evapotranspiration) and non-irrigated control (K) on grape yield and quality was evaluated in 2015 which was climatologically characterized as an average year in this area. Special emphasis was put on grape polyphenolic composition which was monitored from verasion to full ripeness. In comparison to control, yield increase was noticed in all irrigated variants, from 30% in T1 to 48% in T3. All irrigation levels reflected on higher concentrations of juice soluble solids and the highest was determined in variant T1, followlns by T2 end T3. Tltrable acidity was the highest in variant K and T3, and the lowest in Tl. However, the highest concentration of anthocyanins as well as the other groups of phenolic compounds (flavonols, flavan-3-ols and procyanidins) was determined in non-irrigated control, starting from verasion all the way to full ripeness. In full ripeness, variant T1 had higher concentration of anthocyanins than the other two irrigated variants, but still 30% lower than control. A similar difference was determined between control and irrigation treatments for other groups of phenolic compounds.

Ekstrakti polifenola zbog njihovog pozitivnog učinka na zdravlje, imaju brojne primjene u različitim granama industrije, a ponajviše u farmaceutskoj, prehrambenoj te kozmetičkoj. Njihov se učinak na zdravlje temelji na antioksidativnim, antibakterijskim, antimikotičkim svojstvima kao i na sposobnosti apsorbiranja UV zračenja. Pojedine sorte vinove loze sadrže vrlo visoke masene udjele pojedinih polifenola (antocijanini, flavonoli, flavan-3-oli, stilbeni, hidrokscicimetne i hidroksibenzojeve kiseline) pa potencijalno mogu biti dobra sirovina za ekstrakciju polifenola u komercijalne svrhe. U ovu skupinu sorata mogu se ubrojiti i neke sorte nastale međuvrsnim križanjima vinove loze s drugim vrstama roda Vitis (posebice sorta Regent). Ove sorte imaju otpornost prema gljivičnim bolestima pa se u njihovom uzgoju koristi znatno manje sredstava za zaštitu bilja, što njihovo grožđe čini vrlo vrijednom sirovinom za proizvodnju farmaceutskih i drugih pripravaka, a i njihov uzgoj je ekonomski isplativiji. Tijekom proizvodnje pojedinih industrijskih proizvoda, vrlo se često pojedine sirovine podvrgavaju termičkoj obradi, pa stoga mora biti poznata termička stabilnost njihovih pojedinih sastavnica. Cilj ovog istraživanja je odrediti termičku stabilnost ekstrakata polifenola kožica grožđa nakon zagrijavanja pri različitim temperaturama (40 C, 50 C, 60 C) u različitom trajanju (15 min, 30 min, 1 h, 2 h, 3 h, 4 h). Stabilnost pojedinih polifenolnih spojeva sadržanih u ekstraktima kožica grožđa određena je na temelju promjena u njihovim masenim udjelima u odnosu na iste u ekstraktima koji nisu bili podvrgnuti zagrijavanju. Maseni udjeli pojedinih spojeva određeni su tekućinskom kromatografijom visoke djelotvornosti. Provedeno istraživanje jasno pokazuje da se stabilnost pojedinih spojeva značajno razlikuje. Svi ispitani spojevi izrazito su stabilni tijekom zagrijavanja do 40 C. Od ispitanih spojeva, flavan-3-oli su najstabilniji, dok su antocijanini i flavonoli bili najnestabilniji. Uzimajući u obzir samo stabilnost pojedinih antocijanina, antocijanin-3, 5-O-diglukozidi značajno su termički stabilniji od odgovarajućih monoglukozida.

For the characterisation of grape cultivars, the profile and content of flavonoids are important because these compounds impact grape and wine quality. To determine the correct profile and content of flavonoids, the use of robust, sensitive and reliable methods is necessary. The object of this research is to develop a new ultrasound- assisted extraction (UAE) method for the recovery of flavonoids from grape skins using response surface methodology. Optimisation of UAE was performed using a complementary study combining a Box-Behnken experimental design with qualitative analysis by high-performance liquid chromatography. Optimal extraction conditions were obtained using the extraction solvent composed of acetonitrile:water:formic acid (26:73:1, v/v/v) at an extraction temperature of 50°C, an extraction time of 15 min in a single- extraction step and with a solid-to-solvent ratio of 1:80 g/mL. The calculated relative standard deviations for the optimal extraction method were very low, measuring less than 5%. This study demonstrates that numerous factors have strong effects on the extraction efficiency, including the type of organic modifier and its percentage in the extraction solvent, the number of extraction steps, the solid-to-solvent ratio, the extraction time and temperature and, finally, the particular nature of analyte and their position within the grape skin cell.