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Grapevine (Vitis vinifera L.) is one of the most virus prone crop with more than 80 viruses described for this host (Fuchs, 2020). Arbuscular mycorrhizal fungi (AMF), on the other hand, tends to form stable association with the grapevine and contribute to its stress alleviation (Trouvelot et al., 2015). However, influence of AMF on the ability of the grapevine host to cope with virus induced stress is under-investigated. Therefore, in order to get the first look into the grapevine – AMF – virus interplay, we explored the physiological changes in the grapevine connected to the photosynthesis processes. Mixture of different virus combinations (GRSPaV - grapevine rupestris stem pitting virus, GLRaV-3 - grapevine leafroll associated virus 3, GPGV - grapevine pinot gris virus), and two different AMF inoculum (“mono” - Rhizophagus irregularis and “multi” - Rhizophagus irregularis, Funneliformis mosseae and Funneliformis caledonium) was used. The parameters used were net photosynthesis rate, conductance to H2O, transpiration and intercellular CO2 concentration of leaves during three measuring points of one growing season. The effect of AMF resulted in induction of net photosynthesis rate, transpiration and conductance to H2O. The beneficial role of AMF was especially seen in treatments with GRSPaV or GRSPaV coinfection with GLRaV-3. The presented results on photosynthesis point out that AMF can be beneficial for grapevine facing viral infection.

Grapevine leafroll disease (GLD) is one of the most significant grapevine viral diseases, and grapevine leafroll-associated virus 3 (GLRaV-3) is one of the main causes of this disease. The aim of this work was to investigate the effect of GLRaV-3 strains (genetic variants) on physiological parameters on three standard red cultivars Merlot, Cabernet Franc and Pinot Noir and an indigenous Croatian wine grape variety Tribidrag. Total soluble proteins, superoxide dismutase (SOD) activity, hydrogen peroxide, photosynthetic pigments and plant growth were evaluated following 6 and 18 months of inoculation with individual GLRaV-3 strains. The results showed different degree of sensitivity of the tested cultivars to the infection caused by GLRaV-3 strains. After 6 months, we determined that Tribidrag was the most susceptible to infection with GLRaV-3 compared to other cultivars (especially compared to Cabernet Franc and Pinot Noir). Longer infection (18 months) with GLRaV-3 strains singled out Merlot as the most sensitive grape variety as evidenced by decreased growth and photosynthetic pigments. Considering the relative scarcity of this type of research, findings obtained in this study can be used as a guideline for future studies of the impact of virus infections on grapevine.

With more than 80 viruses and virus-like agents described, grapevine is a perennial plant species seriously affected by virus diseases. Mixed infections occur naturally in grapevine host plants and contrary to the well-known grapevine viruses (leafroll and infective degeneration causal agents), limited information is presented on relative expression of grapevine fleck virus (GFkV), grapevine virus A (GVA) and grapevine pinot gris virus (GPGV). In this study, grapevine indicator plants were green grafted with 4 inoculums containing GFkV, GVA and GPGV in different combinations. Cortical scrapings were collected in 3 sampling periods: at dormancy phenological stage (5 and 16 months post inoculation) and the beginning of bud swelling (8 months post inoculation). Total RNA was extracted using commercial kit followed by cDNA synthesis. Using SYBR green based qPCR, relative expression of the virus genes was determined by normalizing their Ct values with those of housekeeping genes. This study showed that relative expression of GVA was decreasing continuously in all three sampling periods. Relative expressions of GPGV and GFkV significantly decreased in bud swelling stage compared to the first dormancy stage, but not from the second. In conclusion, relative expression of virus genes varied significantly in different sampling periods and it was virus dependent.

Background: Grapevine performance can be impacted by more than 80 viruses and virus-like agents, with grapevine leafroll-associated virus 3 (GLRaV- 3), as one of the most dangerous viruses affecting grapevine performance. Mixed infections occur naturally in grapevine populations and GLRaV-3 is usually accompanied by other viruses. Impact of grapevine viruses on GLRaV-3 replication is still unknown due to lack of studies on this subject. Objectives: Relative GLRaV-3 quantification in grapevine of different phenological stages inoculated with GLRaV-3 in combination with other grapevine viruses. Materials and methods: Four different inoculums containing GLRaV-3 accompanied by different combination of other economically important grapevine viruses were inoculated by green grafting on 41 indicator plants during the summer season. Phloem tissue was collected in two different phenophases: the dormancy which occurred five months post inoculation, and the beginning of bud swelling which occurred eight months post inoculation. Total RNA was extracted using a commercial kit followed by the synthesis of cDNA. By using SYBR green qPCR, relative concentration of two genomic GLRaV-3 regions: ORF1a and CP was assessed by normalizing their Ct values with those of housekeeping genes. Results: Relative concentration of GLRaV-3 was generally higher during the dormancy stage, but did not depend on the inoculum composition. It varied significantly in the bud swelling stage where inoculum harbouring the highest number of viruses (six in total) showed significant differences in comparison to other inoculums. The GLRaV-3 concentration at this stage appears to depend more on inoculum composition and infection duration than on sampling phenophase.

Bolest uvijenost lista vinove loze (GLD) jedna je od najznačajnijih virusnih bolesti vinove loze, a virus uvijenosti lista vinove loze 3 (GLRaV-3) jedan je od glavnih uzročnika te bolesti. Dosadašnja istraživanja vezana za GLRaV-3 u Hrvatskoj i svijetu uglavnom su bila usmjerena na proučavanje epidemiologije bolesti i razvoja pouzdanih metoda detekcije, dok su uloga različitih genomskih varijanti GLRaV-3 u etiologiji GLD i odgovor biljke na prisutnost ovog virusa u velikoj mjeri nepoznati.Jedan od glavnih ciljeva istraživačkog projekta GRAPE-PATH3 (u tijeku) podržanog od strane Hrvatske zaklade za znanost, je primjenom molekulranih metoda detekcije istražitidistribuciju ekonomski štetnih virusa vinove loze u autohtonim sortama jadranske Hrvatske, s posebnim osvrtom na GLRaV-3 i njegove genomske varijante U cilju što boljeg razumijevanja promjena koje ovaj patogeni virus uzrokuje u osjetljivim domaćinskim biljkama, različite kombinacije varijanti GLRaV-3 u samostalnoj zarazi i koinfekciji s drugim ekonomski značajnim virusima, su biološki okarakterizirani na setu indikatorskih biljaka. Morfološkim, fiziološkim i biokemijskim metodama istražili smo odgovor na zarazu pri čemu su mjerene promjene primarnog metabolizma, nutrienata i oksidativnog stresa. Potvrđena je dominantna pojavnost GLRaV-3 u odnosu na ostale detektirane viruse i prisutnost genomskih varijanti I i II. Preliminarna analiza rane infekcije ukazuje na značajne razlike između zdravih biljaka, onih zaraženih GLRaV-3 u samostalnoj zarazi i u koinfekciji s drugim virusima. Odgovor loze varira ovisno o sorti i virusnom inokulumu. Ovi rezultati će omogućit bolje razumijevanje patogenosti GLRaV-3 te posljedica koje ovaj virus ima na vinovu lozu u Hrvatskoj i šire, osim okom vidljivih simptoma uvijenosti lista, po kojemu je virus i dobio ime.

Grapevine viruses pose a significant threat to vineyard production by causing damaging effects on plants’ vital processes. Research related to grapevine response to the viruses is still largely unknown. The main objective of the study was to determine changes in vines as a consequence of plant-virus interaction. We initiated this kind of interaction, by graft-inoculating susceptible grapevine varieties (Cabernet Franc, Merlot, Pinot Noir) with different virus inoculums which necessarily contained grapevine leafroll- associated virus 3 (GLRaV-3) in coinfections with other economically important viruses. A Croatian autochthonous variety Tribidrag was also included in the experiment. Morphological, biochemical and physiological parameters related to primary metabolism, nutritive status and oxidative stress were determined. Six months post inoculation, significant differences in measured parameters were found between healthy control plants and those infected, in all varieties except Cabernet Franc. Plant response within each variety varied depending on virus inoculum composition. Data analysis pointed out the varietal specificity in some responses and necessity to observe each variety separately. Finally, parameters as superoxide-dismutase, hydrogen-peroxide, soluble proteins and Fe were changed in all varieties as some kind of common indicators of virus infection. The results obtained in this study enable a better understanding of the virus pathogenicity in grapevine and can be interpreted on three levels: (i) different variety responses to virus infection (ii) specific intravarietal responses in relation to virus composition, (iii) specific physiological parameters are found to potentially serve as general indicators of the studied interaction irrespective of the virus composition or of the grapevine variety.

Background Grapevine leafroll-associated virus 3 (GLRaV-3), the main causal agent of leafroll disease, is one of the most important grapevine virus pathogens worldwide, as also proved for the Mediterranean vineyards in Croatia. There, it is continuously detected mostly in mixed infections with other viruses, but always as the most predominant one (Vončina et al., 2019 ; Hančević et al., 2021). Since the first report on GLRaV-3 population structure (Turturo et al., 2005), genetic variability has been brought to the wider attention, so new divergent variants are continuously discovering all around the globe. Objectives and Material In order to identify and characterize GLRaV-3 variants present within each isolate, thirty-three selected GLRaV-3 positive samples from most widespread native grapevine varieties were analyzed on a molecular basis. Samples included sixteen varieties from Croatian Adriatic coast, now present in the germplasm collection vineyard located at the Institute for Adriatic Crops in Split, Croatia. Methods and Results A fragment (545 bp) of the HSP70h gene of GLRAV-3 was amplified using LC1F and LC2R primer pairs (Turturo et al., 2005) to detect GLRaV-3 presence in all grapevine varieties tested. The PCR conditions were as reported by Turturo et al., except for the final extension, which in our case was prolonged to 15 min. To separate different genomic variants presumably present in each isolate, amplicons were cloned in the in E. coli competent cells. Whenever possible, 20 transformed colonies per sample (in total 586 clones) were randomly selected and analyzed by single-stranded conformational polymorphism (SSCP ; Černi et al, 2008) and sequenced. The phylogenetic analysis of all 139 sequenced variants obtained showed clustering into GLRaV-3 phylogenetic groups I and/or II supported by high bootstrap values. Genomic variants from 55% analyzed samples clustered into phylogenetic group II, while those from 27% samples clustered into phylogenetic group I. Approximately one fifth of samples, 18%, were mixed infected with both variants clustering into both phylogenetic groups I and II. This study emphasizes the predominant presence of GLRaV-3 phylogenetic groups I and II, in indigenous vines in Mediterranea Croatia, either individually or in combination.

Zaraženost vinove loze virusima predstavlja limitirajući faktor u proizvodnji grožđa i vina. Spoznaje o štetnom djelovanju virusa na samu biljku i na kvalitetu grožđa naglašavaju važnost kontrole ovih patogena te primjene kvalitetnog bezvirusnog sadnog materijala. U ovom radu testirano je 16 autohtonih sorti vinove loze na prisutnost 10 ekonomski važnih virusa: Virusa lepezastog lista vinove loze (GFLV), Virusa mozaika gušarke (ArMV), Virusa uvijenosti lista vinove loze -1, -2 i -3 (GLRaV-1, GLRaV-2 i GLRaV-3), Virusa Ai B- vinove loze (GVA, GVB), Virusa pjegavosti vinove loze (GFkV), Rupestris stem-pitting virusa (RSPaV) i Virusa Pinota sivoga (GPGV). Ukupno je analiziran 101 trs primjenom dvije dijagnostičke metode: ELISA (Enzyme linked immunosorbent assay) te RT-PCR (Reverse transcription-polimerase chain reaction). Nije utvrđena nijedna loza bez virusa. Najveća pojavnost zabilježena je kod GLRaV-3 (91, 09 %) i GVA (82, 18 %), a slijedili su RSPaV (67, 33 %), GPGV (54, 46 %) i GLRaV-1 (40, 59 %). Pojavnost ostalih virusa bila je redom: GFkV (16, 81 %), GLRaV-2 (13, 86 %), GFLV (11, 89 %), GVB (10, 89 %) i ArMV (8, 91 %). Najviše trsova imalo je barem 4 virusa (28, 71 %). Nešto manje bilo ih je s 5 (25, 74 %) i 3 virusa (16, 83 %), dok je najmanja zastupljenost bila onih trsova sa 7 virusa (0, 99 %). Visoka pojavnost virusa u promatranoj populaciji i nedostatak adekvatnog programa mjera suzbijanja i kontrole patogena doprinijet će daljnjem širenju virusa u dalmatinskim autohtonim sortama vinove loze.

Plavac Mali is the most important Croatian grapevine cultivar used for red wine production. A direct descendant of Tribidrag also known as Zinfandel and Primitivo, this cultivar is highly appreciated for viticultural practice due to particular adaptation to drought and resistance to various pathogens. Grapevine itself can be affected by more than 70 viruses, some of which are considered to be particularly dangerous to the plant and therefore included in the certification programs of many countries. In this study 35 vines of cv.Plavac Mali from collection vineyard of Institute for Adriatic Crops originating from 13 different locations, were tested for the presence of 10 economically important viruses. Detection for Grapevine leafroll associated virus -1, -2, -3, (GLRaV-1, -2, -3), Grapevine virus A (GVA), Grapevine virus B (GVB), Grapevine rupestris stem-pitting associated virus (GRSPaV), Grapevine fanleaf virus (GFLV), Arabis mosaic virus (ArMV) and Grapevine fleck virus (GFkV) was performed using a RT-PCR multiplex reaction (Gambino and Gribaudo 2006). Grapevine pinot gris virus (GPGV) was tested in individual PCR reaction as described by Saldarelli et al. 2015. The highest occurrence of individual virus was the one of GLRaV-3, detected in 85.71% of samples. The following were GVA with 77.14% and GRSPaV with 40 % and the lowest occurrence was the one of GVB (5.71 %). As for coinfections with multiple viruses plants infected with four and five viruses represent the majority of plant population (more than 50% of population tested). Further investigation was performed on GLRaV-3s HSP70h sequence variants (Turturo et al., 2005). Nine vines were chosen for SSCP analysis and phylogenetic groups I and II were detected showing rather low GLRaV-3 genetic diversity. Monophyletic infections (77.78%) prevailed over polyphyletic (22.22%) and in monophyletic infections Group II was dominant over Group I. This study confirms deteriorating sanitary status of Croatian most valuable red indigenous variety and low genetic diversity of GLRaV-3 isolates.

Hrvatska ima bogate izvore germplazme kultivirane loze. Veliki broj autohtonih sorata je u komercijalnom uzgoju zahvaljujući dugoj tradiciji uzgoja, povoljnom geografskom položaju, te povjesnoj cirkulaciji materijala. Nasuprot kultiviranoj lozi, divlja loza (Vitis vinifera subsp. sylvestris Gmel Hegi) nije bila zanimljiva za komercijalnu proizvodnju pa je vremenom potpuno zanemarena što je rezultiralo s vrlo slabim poznavanjem ovih genetskih izvora u Hrvatskoj. Unutar istraživačkih aktivnosti projekta WI.GRA.GENE podržanog od strane Hrvatske zaklade za znanost istražene su prirodne populacije divlje loze u Hrvatskoj tijekom 2015. - 2018. godine. Određene istraživačke aktivnosti su nastavljene u okviru drugih projekata i nakon formalnog zatvaranja HRZZ projekta. Glavni ciljevi WI.GRA.GENE projekta su bili identificirati preostale populacije divlje loze u Hrvatskoj, te istražiti njene fenotipske i genetske karakteristike. Korištene su moderne metode DNA genotipizacije, kemijske metode za determinaciju specifičnih fenolnih sastojaka u grožđu, te standardni morfološki deskriptori. Rezultati sugeriraju značajnu genetsku vrijednost hrvatske germplazme divlje loze, te pružaju potrebne informacije za njeno očuvanje, te upotrebu u oplemenjivanju i modernom vinogradarstvu.

The wild grapevine (Vitis vinifera subsp. sylvestris Gmel. Hegi) is a dioecious subspecies considered as ancestor of the cultivated grapevine (Vitis vinifera L.). Due to high human pressure to natural plant resources in the last hundred years accompanied with pest, diseases and global climate change, the wild grapevine is highly threatened. The diversity of wild grapevine is poorly represented in gene banks while their habitats constantly declining. The wild grapevine in Slovenia, Croatia and Bosnia and Herzegovina are poorly known. Therefore, current study inventoried remaining populations of wild grapevine in this territory and evaluated their morphological and genetic traits. The inventory started in 2015 confirming several historical populations in eastern Adriatic regions but also finding some new ones not recorded up to now. During prospecting, wild grapevines were found at eight geographically distant locations in this territory. Each observed individual was considered to meet truly morphological criteria (dioecism and leaf morphology) for sylvestris. Ninety-eight sylvestris individuals belonging to 8 populations have been genotyped at 20 nuclear simple sequence repeats (SSR) loci to detect genetic diversity. Distance- and model-based cluster analysis differentiated among samples highlighting at least three different groups. The results showed the existence of considerable level of genetic diversity of wild grapevine but also hidden alleles that could be of interest for breeding programs. The study provides necessary information for conservation management and further characterization of wild grapevine.

The grape germplasm collection in Institute for Adriatic Crops and Karst Reclamation (IAC, HRV048) Split is one of core collections in Croatia. In line with the wider endeavours of long-term conservation and utilization of plant genetic resources in Europe, it places special importance on maintaining genetic diversity of predominantly native Dalmatian varieties. Although IAC collection is already being largely genotyped, 20 accessions maintained in the field collection had unknown or unconfident cultivar status and needed verification of trueness to type. These unknown accessions were accessed from different academic and non- academic sources. Morphological validation was done by standard OIV descriptors encompassing shoot, leaf and cluster characteristics. A standard set of 9 simple sequence repeats (SSR) were amplified and genetic diversity indices were calculated. The allelic data of 20 unknown genotypes were compared with reference SSR profiles from the European database Vitis International Variety Catalogue (VIVC, http://www.vivc.de/) and grape germplasm collection of the United Kingdom. Three accessions proved to be mislabelled and identified as known European grapevine cultivars (Blaufraenkisch, Chardonnay, Merlot), two unknown accessions showed identical genotypes matching Chasselas blanc and Chasellas rose, while 12 unknown genotypes confirmed their declared status. Finally, 3 unknown genotypes of interspecific crosses (Ljana, Orginal, Nero) were not found in VIVC database nor in published literature revealing novel SSR profiles to our knowledge. This study presents necessary information to establish cultivar status (true to type) of 20 unknown accessions from IAC Split grape collection providing clear identity of accessions that is essential for further collection management and achieving maximum genetic diversity in a limited collection capacity.

Proizvodnja industrijske rajčice u Hrvatskoj prevladava u Istri na crvenici 'Terra rossa' koju karakterizira prirodno niska razina organske tvari i nedovoljna količina biološki dostupnog fosfora. Fosfor je neophodan element za postizanje optimalnih prinosa i kvalitetu plodovitog povrća. Stoga u proizvodnim uvjetima često prevladava prekomjerna mineralna gnojidba koja može imati nepovoljan utjecaj na okoliš. Industrijska rajčica posjeduje visok afinitet prema simbiozi s arbuskularnim mikoriznim gljivama (AMG) pa one predstavljaju jedno od inovativnih i ekološki prihvatljivih rješenja za povećanje produktivnosti industrijske rajčice na crvenici. Cilj ovog rada bio je istražiti utjecaj primjene AMG (Glomus intraradices i Glomus mosseae) na prinos, kvalitetu i mineralni sastav ploda industrijske rajčice u proizvodnim uvjetima. Presadnice industrijske rajčice inokulirane s AMG (M) pokazale su veću koncentraciju fosfora, arsena i vanadija te manju koncentraciju olova u plodu u odnosu na presadnice koje nisu bile inokulirane s AMG- kontrola (K). Koncentracije navedenih elemenata bile su značajno ispod maksimalno dozvoljenih koncentracija za ljudsku prehranu. Prilikom berbe, K biljke pokazale su veliki stupanj mikoriziranosti korijena prirodno prisutnim AMG u tlu, no u odnosu na M biljke stupanj mikoriziranosti bio je značajno manji. Između tretmana nije bilo značajnih razlika u prinosu i kvaliteti ploda rajčice.

Reactions that occur when the plant is subjected to Citrus tristeza virus infection often results in triggering numerous defence mechanisms to fight the infection.To understand such kind of infection, changes in nutrient status, total proteins, enzyme activities involved in scavenging stressed conditions, photosynthetic and transpiration rates, membrane permeability and relative water content were analysed in lime plants inoculated with different CTV strains and healthy plants.Clear physiological changes were found between infected and non-infected plants but none between the plants inoculated with different CTV strains. Results suggest that the most of the defence mechanism investigated here were supressed due to the continuous and long-term pressure of CTV biotic stress

The aim of this study was to compare AMF abundance and diversity between cultivated grapevine and its wild relative Vitis vinifera subsp. sylvestris. AMF abundance and diversity were explored in 21 wild grapevine plants in the wide area of Neretva River in southwestern Bosnia and Herzegovina and in eight production vineyards in the neighbouring southern Croatia, whole area with (sub) Mediterranean climate. AMF colonisation was 90-100% in the wild grapevine versus 40%-50% in conventionally cultivated grapevine or up to 70% in organic vineyards, on V. berlandieri×V. rupestris rootstock. Vesicular and arbuscular colonisation of wild grapevine reached 54% and 69% respectively, compared to 21% and 25% in vineyards. AMF spore abundance was similar for both relatives, ~100-1300 per 100 g of soil. In the wild grapevine the majority of the AMF sequences were similar to unidentified Glomus species, with only G. iranicum iden-tified. In vineyards G. intraradices/G. fasciculatum, G. sinuosum/G. coremioides, G. vis-cosum, G.indicum/G. iranicum, and a group of unidentified sequences were found. The wild grapevine was determined as highly AMF receptive with colonisation levels well above the levels found for cultivated grapevine in the same region. Data on AMF diversity in wild grapevine remain preliminary at this stage, with only G. iranicum identified. Inter-estingly, some unidentified Glomus species both from wild grapevine and from organic vineyards grouped together and further wider sets of sequences will show whether these AMF sequences could be characteristic for grapevine, as to date they have not been rec-orded for other plant species.

The eastern Adriatic region which includes Croatia and Bosnia and Herzegovina is considered to be a suitable habitat for survival of wild grapevine Vitis vinifera L. subsp. sylvestris (Gmel.) Hegi. The earliest description of wild grapevine in this region dates back to 1879. It is well known that cultivated grapevine was domesticated from wild grapevine and genetic similarity between them is very high (including sexual compatibility). Natural hybridization is possible between these two subspecies but also with other Vitis species, so wild populations found in natural habitats is either a mixture of wild forms, naturalized cultivated forms and rootstocks escaped from vineyards or hybrids derived from spontaneous hybridizations. This raises the question of identity of native populations of wild forms, their genetic diversity and the presence of hybrids, what is also the first step towards the protection and possible exploration of wild grapevines in modern viticulture. Just recently we started prospection of wild grapevines in the Adriatic karstic region and detected four native populations of wild grapevine in different hydrographic basins in the coastal Croatia and neighboring Bosnia and Herzegovina. The ecological features of discovered sites were described, and individuals were characterized by standard phenotypic OIV descriptors and molecular markers (20 SSR markers). Morphological characteristics of ripen clusters were determined in female individuals. Morphological characteristics specific to wild grapevines such as dioecism (presence of male and female plants) in the population, small round black berries and small clusters in female individuals suggest that the investigated individuals are true sylvestris. STRUCTURE software was used to identify hybrids and to analyze genetic structure of native populations. IDENTITY software was used to identify potential parents for F1 hybrids. According to phenotypic and genetic results several individuals have been detected who do not belong to native populations and can be considered as hybrids or escaped cultivated vines and rootstock. Results improve our knowledge of phenotypic and genetic constitution of wild grapevines on the east Adriatic coast and suggest their necessary conservation.

Dalmatia is rich in germplasm of cultivated grapes (Vitis vinifera L.), possibly thanks to the great tradition of wine growing and favorable geography position where the historical circulation of grapevine was occurring. In the past the genetic resources of wild grapevine (Vitis vinifera subsp. sylvestris) were not of interest to commercial production and application resulting in their complete abandonment with very scarse literature data. The first step towards the exploitation of genetic resources of cultivated and wild grapevines includes study of genetic variability. Here we describe the application of modern DNA genotyping methods, chemical methods of identification of specific phenolic compounds and standard morphological descriptors in order to provide detailed information of the value of germplasm in Dalmatia. In an effort to protect genetic variation of Dalmatian grapes, germplasm collection were established at the Institute for Adriatic Crops and Karst Reclamation in Split, Croatia. The collection contains around 230 accessions of cultivated grapevines, and will be enlarged to the recently collected accessions of wild grapevines. Morphological characteristics and phenolic profiles of cultivated and wild accessions were analyzed. Genetic identification was carried out using microsatellite markers resulting in certain synonyms, homonyms, and assessment of genetic relationship between cultivated and wild grape germplasm. The results improve our knowledge of genetic constitution of cultivated and wild grape germplasm in Dalmatia and suggest possible directions for further conservation and use of these resources.

Ova knjiga predstavlja i opisuje već pomalo zaboravljenu divlju lozu (Vitis vinifera subsp. sylvestris), danas vrlo rijetku i ugroženu šumsku vrstu. Kroz više različitih tematskih cjelina ova knjiga objedinjuje sva prikupljena znanja o divljoj lozi na ovim prostorima ali i šire. Nudi odgovore na brojna pitanja, između ostalih, kakva je to biljka uopće, kako je prepoznati, u kakvim staništima i biljnim zajednicama je možemo očekivati, kako je morfološki razlikovati od svojeg najbližeg srodnika plemenite (kultivirane) loze, kolika je genetska sličnost između njih, pojašnjava zajednice divlje loze i mikoriznih gljiva iz tla, bavi se pitanjem njezine gospodarske zanimljivosti i perspektive za budućnost. Divlja loza je predak plemenite vinove loze stoga je u jednom poglavlju predstavljeno vinogradarstvo Herecegovine kao područja gdje su još uvijek najbrojnije populacije divlje loze.

U ovom radu koncentrirali smo se na utvrđivanje prisustva divlje loze (Vitis vinifera subsp. sylvestris) na području rijeke Krke u Nacionalnom parku Krka. Divlja loza je ugrožena biljna vrsta, a staništa u Europi su joj vrlo ograničena. Divlja loza je jedina autohtona biljna vrsta iz roda Vitis u Europi. Determinirali smo pet lokacija na kojima raste divlja loza. Putem GPS koordinata izrađena je karta rasprostranjenosti divlje loze. Svih pet lokacija se nalaze u neposrednoj blizini rijeke. Fenotipske karakteristike divlje loze istražene su koristeći međunarodne deskriptore za vinovu lozu. Rezultati istraživanih individua sugeriraju prilično veliku bioraznolikost unutar divlje loze. Relativna blizina kontakne zone poljoprivrede i određeni fenotipovi divlje loze upućuju na mogućnost introgresije od strane kultivirane loze. Šumska biljna zajednica u neposrednoj blizini divlje loze vrlo je raznolika i sastavljena je od tipičnih mediteranskih biljnih vrsta i vrsta koje su karakteristične za riječne obale. Ukupno smo determinirali 66 različitih biljnih vrsta, u sloju drveća i grmlja, uz divlju lozu. Smokva (Ficus carica L.) je evidentirana na svim lokacijama što upućuje na njihove slične zahtjeve staništa. Rezultati ovoga istraživanja upućuju na prilično široku rasprostranjenost divlje loze uz obale rijeke Krke te nastavak istraživanja upotrebom molekularnih markera radi sigurnije identifikacije i procjene stupnja introgresije od strane kultivirane loze.

Shoot tip cultures coupled with thermotherapy was used the production of virus-free clones of the Croatian autochthonous and most important red-berried grapevine cultivar Plavac mali. The procedure was successful for the elimination of Grapevine leafroll-associated virus 3 (GLRaV-3) and Grapevine fleck virus (GFkV), but not Grapevine leafroll-associated virus 1 (GLRaV-1). Results showed that a selective virus eradication occurred depending on the initial composition of the viral population of treated samples. When the in vitro growth of cv. Plavac mali explants harbouring different viruses was compared, it was found that, similarly to virus elimination, tissue proliferation was virus composition-dependent. This is a first report on virus elimination in cv. Plavac mali and, by and large, from grapevines in Croatia.

Underground plant to plant communication is a complex and dynamic continuum of exchange of different chemical compounds, having a range of effects from inhibitory to stimulatory ones. This influences also the arbuscular mycorrhizae. We experimentally tested the influence of two selected weeds from Mediterranean Croatian vineyards on mycorrhizae development in neighbouring grapevine (Vitis vinifera L. cv. Plavac mali). The mycorrhizal parameters were compared between pots where there was only grapevine or Plantago lanceolata L. or Tanacetum cinerariifolium (Trevir.) Sch.Bip. alone and the pots with all combinations. Results during six months period showed that plant specie factor significantly influenced development of mycorrhizal intra- and extraradical mycelium and sporulation. Not only that different plant species differed but also grapevine mycorrhizal characteristics differed when combined with different neighbours. Grapevine and T. cinerariifolium individually and in combination generally enabled greater development of arbuscular mycorrhiza comparing to P. lanceolata individually and in combination with grapevine. This was visible in spores’ production, extraradical mycelium length and arbuscular mycorrhizal fungi (AMF) root colonization. Additionally, it was experimentally confirmed that Vitis vinifera L., Plantago lanceolata L., Taraxacum officinale Weber and Trifolium repens L. considerably differed in the composition of AMF community. These results showed that neighbouring plant species significantly influence grapevine’s arbuscular mycorrhizal symbioses establishment in pot cultures. It has implications for understanding real agroecosystems especially when it concerns the choice of appropriate cover crops. Results obtained here pose questions for our future research - Is the reason for observed differences the different AMF community promoted by different plant species or root exudation of stimulatory/inhibitory chemicals when in combination with other plant species or both? And what is the role of signalling compounds (SLs) in recognizing “suitable” neighbours?

Divlja loza je, kao i veliki broj ostalih biljnih vrsta koje rastu u Nacionalnom parku Krka, u prirodnim uvjetima razvila bogatstvo prilagodbi u sklopu samoodrživog ekosustava. Jedna od njih je i podzemna povezanost s micelijem mikoriznih gljiva, koje u svoje netaknute mreže uključuju različite biljne vrste u jednu cjelinu. Kroz takve mreže biljke razmjenjuju hranjiva i informacije i na neki način žive kao jedan veliki organizam.

Divlja (šumska) loza (Vitis vinifera subsp. sylvestris) datira iz vremena Pleistocena (prije više od 10000 godina). Unikatna je i genetski različita od kultivirane vinove loze (Vitis vinifera subsp. sativa). Sadašnja populacija europske divlje loze predstavlja davnu šumsku formu od koje su u procesu domestikacije nastale sve danas poznate moderne sorte vinove loze. Dvodomna je biljna vrsta. U pravilu, divlja loza nastanjuje netaknute šume u Mediteranu sa puno vode u blizini. Tijekom više tisuća godina razvoja civilizacije, divlja loza je doživjela drastične promjene i danas je njezina egzistencija ozbiljno ugrožena. U ovom radu istražili smo prisutnost divlje loze na obalama rijeke Krke kao potencijalno dobrom staništu za divlju lozu. Pronašli smo pet lokacija gdje još uvijek raste divlja loza. Putem GPS koordinata izrađena je karta rasprostranjenosti divlje loze. Svih pet lokacija se nalaze u neposrednoj blizini rijeke. Morfološke karakteristike divlje loze istražene su koristeći međunarodne deskriptore za vinovu lozu. Determinirana je dvodomnost unutar istraživanih individua kao evidentan morfološki marker za divlju lozu. Okolna šumska vegetacija sastavljena je od tipičnih mediteranskih biljnih vrsta. Ukupno smo determinirali 66 različitih biljnih vrsta uz divlju lozu. Primijećen je vrlo jaki stupanj povezanosti divlje loze i smokve (Ficus carica L.) što upućuje na njihove slične zahtjeve staništa. Rezultati ovoga istraživanja upućuju na prilično široku rasprostranjenost divlje loze uz obale rijeke Krke te nastavak istraživanja upotrebom molekularnih markera radi sigurnije identifikacije i procjene stupnja introgresije od strane kultivirane loze.

There are limited numbers of scientific publication regarding genotypic differences which exist among olive cultivars concerning nutrient uptake. For that purpose, the object of our study was to determine possible differences between leaf mineral content of six selected olive cultivars since leaf nutrient analysis is consider being the best method for diagnosing olive tree nutritional status. Plant material was obtained from an olive collection, grown on calcareous soil maintained at Institute of Adriatic Crops and Karst Reclamation, Split, Croatia. The study was conducted with two Croatian autochthonous olive cultivars (Istarska bjelica, Lastovka), two Italian cultivars (Pendolino, Leccino), one Spanish cultivar (Hojiblanca) and one Greek cultivar (Koroneiki). Completely randomized design was applied. Selected olive cultivars in our experiment demonstrated different nutrient leaf concentration, which is of particular importance for fertilization requirements and fertilization practice in Croatian orchards grown on calcareous soil. This study has shown questionably low Mg concentration in all olive cultivars with exception for Hojiblanca cultivar. Also, only Croatian cultivars Istarska bjelica and Lastovka as well as Spanish cultivar Hojiblanca recorded sufficient levels of iron leaf mineral content. Regarding other elements studied (P, K, Ca, Zn, Mn, Cu) all cultivars were above literature cited thresholds for possible deficiencies.

Citrus tristeza virus (CTV) causes tristeza, one of the most damaging diseases of citrus. CTV isolates can be classified in several phylogenetic groups based on the coat protein (CP) gene sequence. Depending on the genotype, scion/rootstock combination and environmental conditions, CTV may induce the development of three syndromes: quick decline (QD), stem pitting (SP) and seedling yellows (SY). The aim of this study was to investigate the effect of different CTV genotypes on symptoms expression in Satsuma mandarins scions grafted on Poncirus trifoliata rootstock in greenhouse conditions, as this combination of plants is the most common in Croatia. CTV monophyletic isolates were molecularly characterized by SSCP-analysis of CP variants, separated by cloning, and sequenced. Six tested isolates, clustered to six different monophyletic groups (Gp:1, 2, 3a, 4, 5, M), were used for the infection of S. mandarin/P. trifoliata hosts. Infected plants were monitored for all changes that could be related to CTV infection. SP were observed in plants infected with Gp3a and Gp4, while those infected with Gp2 developed chlorosis, retarded growth and shortened internodes. The most severe reactions were associated with Gp3a and Gp4 isolates that displayed SP, and Gp2 that developed SY reactions. Although P. trifoliata is known as CTV resistant rootstock, our findings showed that some CTV isolates are able to break the resistance to symptom expression in S. mandarin/P. trifoliata combination.

Na alkalnim, karbonatnim tlima, zbog formiranja teško topivih spojeva, smanjena je dostupnost cinka (Zn), mangana (Mn), i željeza (Fe). Razlog tomu je pored visokog pH i visoka koncentracija aktivnog vapna u tlu koje blokira primanje navedenih hraniva. Cilj ovog istraživanja bio je utvrditi utjecaj gnojidbe sintetskim zeolitima na mineralni sastav lišća masline Olea europaea L. sorte Leccino uzgajane na alkalnom, karbonatnom tlu. U tu svrhu provedeno je istraživanje, u vegetacijskoj komori, u trajanju od 200 dana. Gnojidba Zn, Mn i Fe obavljena je u obliku sintetskog zeolita A (ZA), u kojem su ionskom zamjenom Na ioni zamijenjeni kationima Zn2+, Mn2+ i Fe2+ (Fe3+). Temeljem rezultata istraživanja vidljivo je da je pri tretmanu zeolitima utvrđena statistički značajno veća koncentracija Mn u listu masline dok koncentracije Fe i Zn u listu masline nisu pokazale signifikantnu razliku između tretmana sa ili bez primjene zeolita.

Genetic diversity of 25 Dalmatian sage populations from Croatia and Bosnia and Herzegovina, each consisting of 20 to 25 plants, was assessed using AFLP markers. Four AFLP primer combinations yielded 559 polymorphic markers. Allelic frequencies at AFLP marker loci in each population were calculated from the observed fragment frequencies assuming Hardy- Weinberg equilibrium. Gene diversity ranged from 0.162 to 0.199 with an average value of 0.178. The overall genetic differentiation among populations was very low, FST = 0.042, ranging from 0.006 to 0.081. The analysis of molecular variance indicated that most of the genetic diversity was attributable to differences among individuals within populations (92%). The Fitch-Margoliash tree based on Nei's genetic distance matrix showed that most of the populations tended to group together in accordance to geographical position of their collecting sites. Spatial analysis of genetic diversity revealed a typical pattern of isolation-by-distance.

In modern times urban pollution is a potentially significant risk to public health. Heavy metals are among the most dangerous substances in the environment and their accumulation is predominantly the result of human activity. In cities, heavy metals can enter the human body by inhalation, digestion, direct contact with skin (Wei and Yang, 2010). Phytoremediation, a practice of removing heavy metals from the air and soil by plants, has been in use for a long time. Plants can absorb various hazardous substances from the air and soil and thereby reduce the residual concentration of these toxicants in the environment. Good phytoremediators are plant species that can withstand high concentrations and are able to accumulate a large amount of pollutants. The phytoremediation ability can be increased by symbiotic mycorrhizal fungi. Mycorrhiza is a kind of symbiosis between microscopic fungi and plant roots, where mycorrhizal fungi provide increased absorption of nutrients to the plant via its roots. In case of phytoremediation this means an increased absorption of heavy metals. (Pongrac et al., 2009 ; Hildebrandt et al., 2007 ; Regvar et al., 2003).