Biological spectrum of the weed flora in the Vršac vineyards (Serbia)

Agrotechnical measures are the main factor defining the vineyard weed flora structure and composition, while adequate weed control measures simultaneously ensure that vineyards are being well-managed, thus securing good grapevine health and high quality of wine. Given that the biological spectrum of weeds affects the choice of weed control measures, the aim of this study was to determine the biological properties of the weed flora in Vršac vineyards, by assessing dominant life forms and phenology of the identified weeds. The floristic analysis was conducted during the 2016 vegetation season (March-November) at 60 plots (1 m2), at three field sites. The presence of 97 plant taxa, belonging to 26 families, was determined. The biological spectrum of the vineyards weed flora has shown a thero¬phyto-hemicryptophyte character (therophytes: 57.73% and hemicryptophytes: 34.02%). The scapose herbaceous plants with summer-flowering phenology were dominant within the therophytes and hemicryptophytes. The obtained results have shown a higher weed diversity in vineyards, when compared to previous research of the weed flora in the study area, but similar to more recent studies conducted in the neighbouring countries. Furthermore, the dominant presence of therophytes in the vineyard weed flora was expected, bearing in mind the primarily mechanical weed control measures traditionally applied in vineyard

Riparijalne oblasti kao koridori invazije Xanthium strumarium u Srbiji

Xanthium strumarium L., also known as common cocklebur, is a potentially invasive weed species in Serbia. It is one of the most competitive weeds, strongly affecting the yield of some crops, such as maize, soybean, sunflower, sugar beet, etc. Since watercourses act as important transportation routes for the long-distance dispersal of weeds and the fruit of X. strumarium is easily dispersed by water, our aim was to analyse the degree of X. strumarium invasion in riparian areas of Serbia and examine the role of rivers and canals as its potential invasion corridors. The field research was carried out during the summer months of 2013,2014, and 2015, along the course of 35 rivers and five major canals of the Danube- Tisa-Danube Hydrosystem (HSDTD) in Serbia. Fieldwork was conducted along 100 m long transects of 500 m long river stretches (chosen following the RHS methodology), where the invasive alien weed species presence and abundance were recorded. Over the period of three years, the presence of X. strumarium was recorded along the course of 33 rivers (94.25%), while it was documented along 66.85% of the total number of river stretches. However, along the canals, it was recorded in only 12% of the localities. The data on the distribution ofX. strumarium expand the existing knowledge on the distribution of this economically harmful weed species in our country, while at the same time highlighting riparian areas of rivers as potentially important corridors of its spread.Xanthium strumarium L. u narodu poznat kao obična ili zelena boca, je potencijalno invazivna korovska vrsta na području Srbije. Jedna je od najkompetitivnijih korovskih vrsta, koja jako utiče na prinos nekih kultura, kao što su kukuruz, soja, suncokret, repa, itd. Imajući u vidu činjenicu da vodotokovi predstavljaju značajne transportne puteve za disperziju korovskih vrsta na veće razdaljine, naš cilj je bio da analiziramo stepen invazije X. strumarium u riparijalnim područjima Srbije i ispitamo kakva je uloga reka i kanala kao njegovih potencijalnih koridora invazije. Terenska istraživanja obavljena su u periodu letnjih meseci 2013, 2014. i 2015. godine, duž toka 35 reka i pet glavnih kanala hidrosistema Dunav-Tisa-Dunav u Srbiji. Istraživanja su vršena na 100m dugim transektima u okviru 500 m dugih deonica rečnog toka (odabranih u skladu sa RHS metodologijom), gde su beleženi prisustvo i pokrovnost stranih invazivnih biljnih vrsta. Tokom trogodišnjeg perioda istraživanja, prisustvo X. strumarium zabeleženo je duž toka 33 reke (94,25%), a duž 66,85% od ukupnog broja rečnih deonica. Međutim, duž toka kanala, ova potencijalno invazivna vrsta registrovana je na samo 12% lokaliteta. Podaci o rasprostranjenju vrste X. strumarium proširuju postojeće znanje o rasprostranjenju ove ekonomski značajne korovske vrste u našoj zemlji, dok u isto vreme ističu riparijalne oblasti reka kao potencijalno značajne koridore njenog širenja

The digital database of aquatic and semiaquatic vegetation in Serbia

Despite the absence of a centralized national phytocoenological database of Serbia, over 16,000 relevés of all vegetation types have been gathered and stored in the database “Phytocoenosis of Serbia” as a result of the Project “Habitats of Serbia”. However, as the data on aquatic and semiaquatic vegetation comprise only 5% of the collected relevés, the aim of this paper is to expand on this, complete the database and present the data on these vegetation types in Serbia. The work included the expansion of the existing database with the addition of relevant sources, their digitalization, using Flora and Turboveg programs, and their subsequent georeferencing, using OziExplorer and DIVAGIS softwares. Consequently, the phytocoenological database on aquatic and semiaquatic vegetation in Serbia now stores 1,720 relevés from 243 phytocoenological tables, collected and published by 24 authors during the period of 70 years (1940–2010), with the majority of the relevés collected over the last decade (56.40%). Phragmito-Magno-Caricetea Klika in Klika et Novák 1941 (Syn: Phragmitetea communis R. Tx. et Prsg. 1942), Potametea Klika in Klika et Novák 1941 (Syn: Potametea R. Tx. et Preising 1942) and Lemnetea de Bolós et Masclans 1955 (Syn: Lemnetea minoris W. Koch et R. Tx. 1955) have proven to be the most represented classes, while Scirpo-Phragmitetum W. Koch 1926 (nomen ambiguum) and Salvinio natantis-Spirodeletum polyrrhizae Slavnić 1956 are associations with the highest number of relevés in the database. Accordingly, the most common species (>500 relevés) are Ceratophyllum demersum L. subsp. demersum, Lemna minor L. and Spirodela polyrhiza (L.) Schleiden

The influence of integral and organic growing systems on sugar content in selected tomato types and cultivars

Interest in production of protected crops has grown significantly over the past decade. Different cultivation systems (conventional, integral, and organic) affect the biological activity, which is ultimately reflected in the high quality of the fruits of different vegetable crops. In accordance with the requirements for health-safe products without residues of harmful substances in fruits, there is an increasing need for the production of tomatoes in integral and organic production systems. One of the most important features of these vegetables is their high quality and health safety, high nutritional and biological value. Agricultural production systems and growing practices are critical factors in determining the nutritional quality of tomato fruits [1]. In tomato, the sugar content is one of the important factors and one of the most significant parameters from the aspect of food quality [1]. Therefore, the aim of this work is to monitor fluctuations in sugars content, as parameters that determine the nutritional value in tomato cultivars, induced by growing under integral and organic conditions. For this purpose, a set of sixteen samples of four types of tomatoes - beef, grapolo, mini and midi plum, and cherry - was analyzed. Each type of tomato included two varieties, grown in two agricultural systems - integral and organic. The sugars profile was obtained using High-Performance Anion Exchange Chromatography with Pulsed Amperometric Detection (HPAECPAD). The content of eleven sugar components was determined. Fructose and glucose were the major sugar compounds [2], while the sugar microcomponents were trehalose, arabinose, melibiose, sucrose, isomaltose, gentiobiose, raffinose, maltose, and panose. The results showed differences between samples produced in integral and organic growing systems, primarily in microsugar components. Higher content of trehalose and melibiose was found in samples obtained from organic production. Fig.1. Principal Component Analysis (A)- The difference between integral (I) and organic (O) type of production; score plot (1a) – tomato samples: integral samples (I) 9-14, organic samples (O) 1-8, and loading plot (1b), and results of the Mann-Whitney U test (B) - sugar markers of type of production. Acknowledgments: The authors would like to thank the Zeleni hit d.o.o. from Belgrade, Serbia, for field trials and support. This work has been supported by the Ministry of Science, Technological Development and Innovation of Republic of Serbia, Contract number: 451-03- 47/2023-01/200168, 451-03-47/2023-01/200288 and 451-03-47/2023-01/ 200045. References: [1] E. Rosa-Martínez, M. D. García-Martínez, A. M. Adalid-Martínez, L. Pereira-Dias, C. Casanova, E. Soler, M. Rosario Figas, M. Dolores Raigon, M. Plazas, S. Soler, J. Prohens, Food Research International, 147 (2021) 110531. [2] C. Agius, S. von Tucher, B. Poppenberger, W. Rozhon, MethodsX, 5 (2018). 537-550

Konzervacioni status makrofitske vegetacije u kopovima šljunka u plavnom području donjeg toka reke Drine

Human-made aquatic habitats, such as gravel pit lakes could be alternative habitats and biodiversity refugia for aquatic biota. The aim of this study was to determine conservation value of gravel pit lakes in the Drina river floodplain using rarity and naturalness of aquatic macrohytes. Conservation value was calculated for 14 lakes. The obtained results showed that the analyzed gravel pits along the Drina River represent an optimal habitats for rare and endangered macrophytic flora

Značaj riparijalnih područja Srbije u širenju invazivnih biljnih vrsta

Procenjuje se da je oko 13.000 biljnih vrsta širom sveta postalo naturalizovano izvan njihovog prirodnog areala, pri čemu područje Evrope broji skoro 6.000 naturalizovanih alohtonih biljnih vrsta. Smatra se da tip staništa predstavlja najbolji pokazatelj nivoa invazije na regionalnom nivou, pri čemu su riparijalna ili priobalna staništa među onima koja se karakterišu najvišim nivoom invazije. Riparijalne zone karakteriše mozaik različitih tipova vegetacije koji se nalaze pod snažnim pritiskom antropogenih aktivnosti, što dodatno doprinosi invazibilnosti ovih fragilnih područja. Kao posledica toga, riparijalna staništa postaju centri diverziteta stranih i invazivnih biljnih vrsta, a ujedno i potencijalni izvor njihovog daljeg prodora u okolna prirodna staništa i agroekosisteme. Imajući sve navedeno u vidu, cilj istraživanja bio je da se analizira stepen invazije u riparijalne zone na području Srbije. Terenska istraživanja obavljena su u periodu jul-septembar 2013-2016. godine, pri čemu je analizirano ukupno 250 lokaliteta na području Srbije. Od ukupnog broja lokaliteta, u istraživanje je uključeno 217 lokaliteta u riparijalu 39 reka (osam rečnih slivova) i 33 u riparijalu šest deonica kanala hidrosistema Dunav-Tisa-Dunav (HS DTD). Podaci o brojnosti i pokrovnosti 26 analiziranih invazivnih biljnih vrsta beleženi su na obali reke/kanala, u okviru transekata dužine 100 m. Kanonijsko korespodentna analiza (CCA) rađena je u programu CANOCO 5.0. Od 26 taksona čije je prisustvo analizirano, taksoni sa najvećim brojem nalaza su Xanthium strumarium L. subsp. italicum (Moretti) D. Löve, Amorpha fruticosa L., Erigeron canadensis L., Robinia pseudoacacia L. i Echinochloa crus-galli (L.) P. Beauv. Biogeografska analiza pokazala je da su u riparijalnim područjima Srbije dominantno prisutne invazivne vrste poreklom iz Severne Amerike (68% nalaza), praćene južnoameričkim i azijskim vrstama, koje su zastupljene sa 16%, odnosno 14% nalaza. U pogledu biološkog spektra, registrovan je najveći broj jednogodišnjih invazivnih biljnih vrsta (terofite, 60%), dok višegodišnje drvenaste vrste (fanerofite) predstavljaju drugu najviše zastupljenu grupu (16%). Rečni slivovi Dunava, Južne Morave, Zapadne Morave i Timoka se ističu prisustvom invazivnih biljnih taksona, sa 384, 131, 129 i 110 nalaza, redom, pri čemu je, veza pripadnosti vodotoka određenom rečnom slivu i zastupljenosti pojedinačnih istraživanih taksona, dodatno potvrđena rezultatima CCA analize. CCA analiza je ukazala da određeni taksoni pokazuju jaču preferenciju prema rekama pojedinih rečnih slivova, npr. Helianthus tuberosus L. je u većoj meri zastupljen u riparijalu reka sliva Zapadne Morave, dok je Reynoutria x bohemica Chrtek & Chrtková u najvećoj meri prisutna u riparijalnim zonama u okviru slivova Zapadne Morave i Drine. Sa druge strane, vrste Asclepias syriaca L., Solidago gigantea Ait. i Xanthium spinosum L. su u većoj meri zastupljene u riparijalu kanala HS DTD, u odnosu na rečne tokove. Analizom celokupnog seta podataka o distribuciji, brojnosti i pokrovnosti analiziranih taksona, slivovi Dunava, Zapadne Morave i Kolubare se mogu označiti kao glavni koridori širenja većine istraživanih taksona, dok je moguće očekivati da će se u narednom periodu, usled klimatskih promena, slivovi Save, Velike i Južne Morave takođe naći pod snažnim pritiskom daljeg širenja invazivnih biljnih vrsta. Porast u broju i pokrovnosti invazivnih biljnih vrsta moguće je očekivati i u riparijalnim zonama visokoplaninskih predela i na području jugozapadne Srbije (doline Lima, Ibra i njihovih pritoka), takođe kao posledica klimatskih promena

Plant invasions in riparian areas of the Middle Danube Basin in Serbia

Riparian areas experience strong invasion pressures worldwide and represent important points of spread for invasive alien plants (IAPs) in the European mainland. The Danube Basin is a well-known point of high plant invasion levels. Given that the middle part of the Danube Basin is critically understudied and the general lack of data for Serbia, the study aimed to provide an insight into the spatial patterns of plant invasions in the riparian areas of Serbia (Middle Danube Basin area). A total of 250 field sites, distributed along 39 rivers (nine catchment areas) and six canal sections, were studied during a four-year period (2013–2016) for the presence and abundance of IAPs. At the landscape scale, we studied distribution patterns of IAPs, differences in invasion levels in different catchment areas and between rivers and canals. At the local scale, we investigated how the proximity to roads/railway lines, housing areas, different land-use types (primarily agriculture), and dominant vegetation on site related to invasion patterns. Of the 26 studied IAPs, those with a well-known weedy behavior, long history of cultivation and strong affinity for riparian areas prevailed in the study area. Riparian zones of the Danube catchment exhibited the highest invasion levels in terms of IAPs richness and abundance, followed by the catchment areas of the Timok, Sava and Zapadna Morava rivers. Surprisingly, the Danube-Tisa-Danube canal network had the lowest invasion level. At the local scale, agriculture in proximity of the field site and dominant vegetation on site were observed as significant predictors of the invasion level. On the other hand, proximity to roads/railway lines and housing areas was not related to the invasion level. Finally, our study provides the first systematic overview of IAPs’ distribution data for riparian areas of the Middle Danube Basin in Serbia, which could provide a basis for long-term monitoring of IAPs and development of future management plans

The contemporary records of aquatic plants invasion through the Danubian floodplain corridor in Serbia

Aquatic ecosystems are particularly vulnerable to introductions of non-indigenous species, which potentially lead to major disruptions in the functioning of these invaluable habitats. Despite the significance of aquatic systems, there is no collated data available on the aquatic non-native plants in Serbia. Consequently, the aim of this paper is to provide a first overview of the aquatic alien plant species recorded in Serbia, their origins, current distribution, habitat preferences and invasiveness status. This study comprises the results of a comprehensive literature review and extensive field research on lake and river systems over a nine year period (2007-2015), with the addition of data from the IASV database and Joint Danube Surveys 2 & 3. The results of this study show the presence of seven non-indigenous aquatic plant species in Serbia which, despite being a relatively low number when compared to France and Germany, is in line with most of the countries of the region (e.g. Croatia, Bulgaria and FYR Macedonia). The majority of the species are native to the Americas, which concurs with the results of previous studies at the European level, with only one species of Asian origin. The most abundant of the registered non-natives is Vallisneria spiralis, followed by Azolla filiculoides and Elodea nuttallii, while Cabomba caroliniana, as the newest registered aquatic alien in Serbia, has the least number of records. All of the registered non-natives predominantly occur in running waters, including as much as 91% of the records for Elodea canadensis and 85% for Elodea nuttalli. Vallisneria spiralis is present in five different EUNIS habitat types, while Paspalum distichum was recorded predominantly along the River Danube, thereby highlighting it as P. distichum's main corridor of spread in Serbia. The distribution of all the recorded non-indigenous species is primarily linked to the northern, low-lying part of Serbia-i.e. Vojvodina Province. Such a distribution pattern is concordant with the presence of adequate habitat types, the courses of potential international invasion corridors in the Sava and Danube rivers and the position of the elaborate irrigation canal network of the Danube-Tisa-Danube Hydrosystem; but also with the frequency of studies carried out in this region over the years. Of the seven aquatic aliens present in Serbian waterbodies, three are considered to be highly invasive and one potentially invasive, while two have also been included in the list of 150 most widespread alien species in Europe

Catchment area, environmental variables and habitat type as predictors of the distribution and abundance of Portulaca oleracea L. in the riparian areas of Serbia

Portulaca oleracea L. is one of the most widely distributed plant species, invading a host of worldwide regions. Rivers and canals, as corridors connecting neighboring habitats, are known to exhibit high invasion levels. Consequently, the aim of this paper was to show which catchment areas, environmental factors and habitat types can be seen as predictors of the presence of this invasive species in the riparian areas of Serbia. Field research was carried out at 250 field sites, where the cover and abundance of P. oleracea, relevant environmental variables and habitat type were recorded. Redundancy analysis (RDA) and response curves fitted using a generalized linear model (GLM) were used to show the relation of the cover of P. oleracea and the following variables: catchment area, predominant bank material, elevation, and the total number of invasive species on site. A non-metric multidimensional scaling (NMDS) was used to group sites where P. oleracea was found, based on the values of its cover. In general, primarily the rivers in the northern, low-lying part of Serbia can be seen as important corridors of the spread of P. oleracea. Its dominance is especially associated with areas draining into the Danube and Sava rivers and field sites characterized by a high pressure of invasive plants. Of the total number of records, the highest number of invaded field sites was recorded along the Danube, Tisa and Zapadna Morava rivers. Regarding the environmental and habitat predictors, the results have shown that the abundance of P. oleracea is associated with gravelly and sandy banks and grassland habitat types, primarily anthropogenic herb stands

Distribution of economically important weed species in the riparian and roadside vegetation of Serbia

Transportation corridors such as waterways and road networks serve as an entranceway for invasive and economically important weed species. The unstable environment of riparian areas and nutrient enrichment of road verges promotes the establishment and spread of these species, which may have a negative effect on nearby arable land, leading to severe yield reductions. We aimed to register the presence and frequency of five selected weed species (Chenopodium album, Cirsium arvense, Convolvulus arvensis, Cynodon dactylon, and Lactuca serriola) within these linear corridors. Sites along waterways were visited during 2013-2016, and road networks during 2018-2019. At each site, studied weed species were registered along 100 m transects, resulting in 250 localities along waterways and 180 near road networks. The most frequent species is C. arvensis, followed by L. serriola and C. album, while less prevalent species are C. arvense and C. dactylon. The main characteristic of studied species is their preference for roadside habitats, except for Chenopodium album, which is more common in riparian areas