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POREĐENJE JESENJEG I PROLEĆNOG PLODONOŠENJA NOVOINTRODUKOVANIH REMONTANTNIH SORTI MALINE GAJENIH U SUPSTRATU
No full textCilj ovog rada bio je da se ispita rodni potencijal i kvalitet ploda šest remontantnih sorti maline (‘Dafne’, ‘Primalba’, ‘Kokanee’, ‘Paris’, ‘Versailles’ i ‘Enrosadira’) gajenih u saksijama u dvogodišnjem proizvodnom sistemu. Istraživanje je izvedeno u kolekcionom zasadu maline na imanju kompanije “Floriva” (opština Ivanjica). Sadnja je izvedena u proleće 2022. godine u saksije zapremine 10 l ispunjene Galuku kokosovim supstratom. Ispitivanja su izvedena merenjem parametara rodnog potencijala, fizičkih i hemijskih osobina ploda na jednogodišnjim izdancima u jesenjoj berbi 2022. godine i na dvogodišnjim izdancima u prolećnoj berbi 2023. godine. Najmanji prosečni broj plodova i prinos po izdanku registrovan je kod sorte ‘Primalba’ (130,2 i 691 g/izd., po redosledu), bez postojanja značajnih razlika između jesenjeg i prolećnog plodonošenja. Najveći prosečni prinos po izdanku imale su sorte ‘Paris’ i ‘Enrosadira’ (1081,3 g i 1116,3 g/izd., po redosledu). Značajno povećanje prinosa je zabeleženo na dvogodišnjim izdancima kod sorti ‘Paris’, ‘Enrosadira’ ‘Dafne’ i ‘Versailles’, dok je sorta ‘Kokanee’ imala 2 puta veći prinos na jednogodišnjim izdancima (1384,7 g/izd.). Najveću prosečnu težinu ploda imala je sorta ‘Dafne’ (6,11 g), a najnižu sorta ‘Kokanee’ (4,14 g). Značajno povećanje težine ploda registrovano je u jesenjem plodonošenju kod četiri sorte (‘Dafne’, ‘Primalba’, ‘Kokanee’ i ‘Versailles’), dok je sorta ‘Enrosadira’ povećala težinu ploda u prolećnoj berbi (6,45 g), a kod sorte ‘Paris’ nisu uočene značajne razlike u težini ploda između jesenje i prolećne berbe. Sorta ‘Versailles’ je imala značajno veću prosečnu čvrstoću ploda 1 i 2 (1,08 i 0,42 g, po redosledu), dok su sorte ‘Paris’ i ‘Enrosadira’ ispoljile značajno veću kohezivnost ploda (0,22 i 0,21, po redosledu) u poređenju sa ostalim sortama. Prosečan sadržaj rastvorljive suve materije se kretao od 8,48% (‘Dafne’) do 10,63% (‘Paris’), pri čemu je sorta ‘Dafne’ imala stabilan sadržaj između jesenje i prolećne berbe, a značajno povećanje u jesenjoj berbi registrovano je kod sorti ‘Kokanee’, ‘Paris’i ‘Versailles’. Sorta ‘Kokanee’ je imala najveći prosečni sadržaj ukupnih fenola (1,25 mg ekv. galne kis. /g sv.m.pl.), a sorta ‘Paris’ najveći sadržaj ukupnih antocijanina u plodu (19,98 mg ekv. c-3-gluk./100 g sv.m.pl.). Najniži sadržaj ukupnih fenola i ukupnih antocijanina registrovan je kod sorte ‘Enrosadira’, koja se ističe po visokom sadržaju vitamina C (33,73 mg/100 g sv. m.pl.). Većina ispitivanih sorti je ispoljila bolje proizvodne performase u dvogodišnjem sistemu gajenja, izuzev sorte ‘Kokanee’, koja se jedina može preporučiti za gajenje u jednogodišnjem ciklusu za jesenju proizvodnju
XRD and XPS analysis of bismuth ferrite ceramics doped with lanthanum and europium
No full textУ овом раду представљени су резултати анализе рендгенске дифракције (XRD) и рендгенске фотоелектронске спектроскопије (XPS) керамике бизмут-ферита (BiFeO3) допиране лантаном и еуропијумом. Серија узорака очекиване стехиометрије Bi1−zLaxEuyFeO3 (z = x + y) добијена је различитим допирањем BiFeO3: лантаном (x = 0,05; 0,10; 0,15), еуропијумом (y = 0,05; 0,10; 0,15) и лантаном и еуропијумом (x = y = 0,025; 0,05; 0,075).
Кристална структура узорака је утачњена у просторној групи R3c коришћењем XRD података и софтвера Fullprof и SmartLab Studio (Rigaku Со.). Фазни прелаз из ромбоедарске (П.Г. R3c) у ромбичну β-BiFeO3 фазу (П.Г. Pnma) примећен је у узорцима допираним са 15 mol.%. Праћена је промена параметара решетке, ah и ch, и релативна промена запремине јединичне ћелије, (V−V0)/V0, са допирањем. Јединична ћелија се скраћује дуж [001] правца (ch се смањује) на скоро исти начин за исти степен супституције, z, без обзира на врсту катјона (La3+ и/или Eu3+). Приметно је и линеарно смањење параметра решетке ah, али је оно одређено типом катјона. Највеће смањење запремине јединичне ћелије испољено је у керамици бизмут-ферита допираној са 15 mol% еуропијума. Допирање јонима лантана мање утиче на смањење средње величине кристалита керамике бизмут ферита, него допирање јонима еуропијума. Снимљени XPS спектри су доказали присуство јона Bi3+, Fe3+/Fe2+, као и ваканција кисеоника у кристалној решетки узорака. Допирање лантаном и еуропијумом у концентрацијама x = 0,10 и y = 0,10 довело је до смањења концентрације ваканција кисеоника.Here, we presented the results of X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis of bismuth ferrite (BiFeO3) ceramics doped with lanthanum and europium. A series of samples with the expected stoichiometry Bi1−zLaxEuyFeO3 (z = x + y) were obtained after doping with different concentrations of lanthanum (x = 0.05, 0.10 or 0.15), europium (y = 0.05, 0.10 or 0.15) and both, La and Eu, (x = y = 0.025, 0.05 or 0.075).
The crystal structure of the samples has been refined in R3c space group, using XRD data and the Fullprof and SmartLab Studio (Rigaku Co.) tools. The phase transition from the rhombohedral (S.G. R3c) to the orthorhombic β-BiFeO3 phase (S.G. Pnma) has been observed in the samples doped with 15 mol%. Evolution of the unit cell parameters, ah and ch, and relative unit cell volume changes (V−V0)/V0 were followed upon doping relative to the unsubstituted BiFeO3. The unit cell is shortened along [001] direction (ch was decreased) in almost the same way, for the same degree of substitution (z = x + y), regardless of the type of substitutional cations (La3+ and/or Eu3+). The linear decrease of the unit cell parameter ah is also found, but its decreasing rate is determined by the cation type. The highest decrease in the unit cell volume was observed in the bismuth ferrite doped with 15 mol% Eu3+. In addition, the lanthanum doping had a little less effect on the reduction of the average crystallite size of bismuth ferrite ceramics than doping with europium ions. XPS spectra showed the presence of Bi3+, Fe3+/Fe2+, as well as oxygen vacancies in the crystal lattice of the samples. Doping with 10 mol% lanthanum ions or 10 mol% europium ions led to a decrease in the concentration of oxygen vacancies in their crystal lattices
Signaling function of NH4+ in the activation of Fe-deficiency response in cucumber (Cucumis sativus L.)
No full textNitrogen (N) is present in soil mainly as nitrate (NO3–) or ammonium (NH4+). Although the significance of a balanced supply of NO3– and NH4+ for optimal growth has been generally accepted, its importance for iron (Fe) acquisition has not been sufficiently investigated. In this work, hydroponically grown cucumber (Cucumis sativus L. cv. Maximus) plants were supplied with NO3– as the sole N source under –Fe conditions. Upon the appearance of chlorosis, plants were supplemented with 2 mM NH4Cl by roots or leaves. The NH4+ treatment increased leaf SPAD and the HCl-extractable Fe concentration while decreased root apoplastic Fe. A concomitant increase in the root concentration of nitric oxide and activity of FRO and its abolishment by an ethylene action inhibitor, indicated activation of the components of Strategy I in NH4+-treated plants. Ammonium-pretreated plants showed higher utilization capacity of sparingly soluble Fe(OH)3 and higher root release of H+, phenolics, and organic acids. The expression of the master regulator of Fe deficiency response (FIT) and its downstream genes (AHA1, FRO2, and IRT1) along with EIN3 and STOP1 was increased by NH4+ application. Temporal analyses and the employment of a split-root system enabled us to suggest that a permanent presence of NH4+ at concentrations lower than 2 mM is adequate to produce an unknown signal and causes a sustained upregulation of Fe deficiency-related genes, thus augmenting the Fe-acquisition machinery. The results indicate that NH4+ appears to be a widespread and previously underappreciated component of plant reduction-based Fe deficiency response
Using different receptor models to determine the sources of available forms of potentially toxic elements in Rasina District – A case study
No full textDetermining the sources of potentially toxic elements (PTEs) in soil is one of the basic postulates for dealing with them properly in the future. In addition to total PTEs, it is extremely important to identify sources of available PTEs, for two reasons: 1. to determine their actual impact on the ecosystem, and 2. to establish whether sufficient levels are present in soil if they are necessary for plant development. In this study, two receptor models were used to determine sources of diethylenetriaminepentaacetic acid (DTPA)-extractable PTEs in soil in Rasina District, Serbia in 2017: Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF). Appropriate PCA was used for total forms and the accuracy of the models in determining sources was tested by comparing them. Based on the results, obtained in quite a complex geological environment, the universality and superiority of the PMF model in so-called diffusion systems, which are more prone to change, was confirmed. The PMF model took geological and anthropogenic sources, characteristic of PCA of total PTEs, into account in equal measure, as well as pedological sources, which are more characteristic of PCA of DTPA-PTEs. The accuracy of the model was also confirmed by the greater number of factors, i.e. 5 in the PMF model compared to 3 in PCA. Based on the obtained results, it is clear that the use of the PMF model is justified when determining sources of individual available PTEs in soil
Early Paleozoic Cenerian (Sardic) geodynamic relationships of peripheral eastern north Gondwana affinities: revisiting the Ordovician of the Getic/Kučaj nappe (eastern Serbia)
No full textRegional tectonic synthesis suggests that a segment of the bipartite eastern Gondwana-type Carpathian-Balkan nappe-stacked Getic/Kučaj/Supragetic basement (eastern Serbia) experienced Cambro-Ordovician Cenerian (Sardic) accretionary-type deformation. The Ordovician basement of the Alpine Getic/Kučaj nappe exposes an earlier-mapped shallow-marine transgressive-type Fe-silicate-rich ironstone sequence. The Ordovician ironstone is used as second-order evidence of a hitherto untraceable tectonically-driven unconformity. Early Paleozoic compression is consistent with the controversial latest Cambrian to intra-Ordovician Cenerian (Sardic) interval, documented by (i) a 488 Ma metamorphic event and available detrital zircon data (Serbo-Macedonian gneissic unit), (ii) a deformed Lower Ordovician Getic/Kučaj brachiopod assembly, and (iii) an intra-Ordovician unconformity dividing the Supragetic basement/”Vlasina complex”. The data further imply that mafic gabbro-dominating sills, cropping out in the northern Getic/Kučaj unit, are consistent with Ordovician back-arc activity. The Getic/Kučaj gabbro is Ordovician in age, piercing a Neoproterozoic–Cambrian (Lower Ordovician) Supragetic/”Vlasina complex”, overlain by a transgressive Silurian–Devonian sedimentary sequence. The emergence of Ordovician mafic intrusions reflects submarine volcanism, while deep-water redox conditions were capable of a sustained supply of Fe (similar to Sardinia). In terms of tectono-palaeogeographic reconstructions, the origin of Ordovician shortening and mafic volcanism is often challenged. The latter is broadly analogous with the embryonic eastern Rheic Ocean, corresponding additionally to the Armorican spur and related intra-continental magmatism
Tithonian limestone as a marker of early contraction of NeoTethyan Vardar Ocean: structural constraints on the latest Jurassic–earliest Cretaceous “docking” (Dobroljupci, Kuršumlija, Jastrebac Mt., Serbia)
No full textThe Jurassic–Cretaceous East Vardar Zone (EVZ) is a NNW–SSE-directed NeoTethyan back-arc crustal amalgamation that passes through Romania, Serbia, Bulgaria, North Macedonia, and Greece. This somewhat elongated Jurassic back-arc ocean underwent early compression, “docking” and nappe-stacking in the latest Jurassic–earliest Cretaceous. The Tithonian(Berriasian) limestones, which stratigraphically overlie the Middle Jurassic oceanic crust, are not only crucial markers of the latest Jurassic contraction and exhumation but also bear significant implications for the NeoTethyan Vardardevelopments (evidence of paleokarstification). During the latest Jurassic–earliest Cretaceous compressional event, the oceanic crust belonging to the EVZ interacted with the Dacia Mega-Unit and its Serbo-Macedonian continental margin. Byintroducing new structural observations, this study covers the interference character between the EVZ periphery and thewestern Serbo-Macedonian Unit. Supported by previous mapping results, new structural data are extracted from several keyoutcrops distributed across central Serbia (Dobroljupci, Kuršumlija, Jastrebac Mt.). The analyses of geodynamic implica-tions related to the NeoTethyan Vardar contraction have outlined the latest Jurassic-earliest Cretaceous accretionary-typedeformation embedded in the peripheral units (Tithonian-Berriasian limestones, mélanges, Serbo-Macedonian gneiss). Thesefindings are significant as they provide a deeper understanding of the geological processes that shaped this region duringthe mid-Mesozoic. Despite Late Alpine overprinting, the latest Jurassic arc-type “soft collision” or “docking” (no evidenceof significant crustal thickening with a very limited obduction) produced the newly observed NNE-SW oriented folds. Thefolds are observed within the Jurassic carbonate rocks and greenschist-facies rocks of likely similar age and origin (train ofsteeply plunging synforms, D1). The tectonic resetting and initiation of post-collisional progressive subduction remobilizedthe stalled remnant of the Vardar marine corridor after the short-term Berriasian exposure and palaeokarstification. Suchtectonic developments triggered a foreland-type subsidence and accumulation of the clastic-carbonate Lower Cretaceous“paraflysch” on top of the EVZ ophiolites/mélange/Tithonian limestones. However, the new depositional cycle and the oldestLower Cretaceous paraflysch sequence remain devoid of ophiolite inclusions
Phenolics and Sesquiterpene Lactones Profile of Red and Green Lettuce: Combined Effect of Cultivar, Microbiological Fertiliser, and Season
Get PDFThe main goal of our study was to find an optimal combination of tested factors to achieve lettuce rich in bioactive compounds sustaining its pleasant taste. We examined three red and three green cultivars in a greenhouse using two microbiological fertilisers (EM Aktiv and Vital Tricho), and their combination. Plants were grown in three consecutive growing seasons (autumn, winter, and spring). Lactones accumulated in autumn, whereas phenolics’ concentration rose during winter. Red cultivars showed higher phenolics and lactone content, where chicoric acid and luteolin-7-glucoside were the most abundant in the ‘Gaugin’ winter trial. Lactucopicrin was the predominant lactone among tested cultivars with the highest value in the red cultivar ‘Carmesi’. Solely applicated, the fertiliser EM Aktiv and Vital Tricho led to significantly higher phenolic acid and dihydrolactucopicrin content, while combined, there were notably increased levels of all detected lactones. Application of single fertilisers had no effect on flavonoid content, while the combination even reduced it. A sensory analysis showed a negative correlation between overall taste and total sesquiterpene lactones, lactucopicrin, caffeoylmalic, and chlorogenic acid, indicating a less bitter taste with decreasing content of these compounds. Our findings indicate that the cultivar, fertiliser, and growing season jointly affected all of the tested parameters, highlighting the differences in the application of EM Aktiv, Vital Tricho, and their combination
Chemical activation of high volume fly ash binders by selected sodium salts
No full textFly ash (FA), a by-product of coal combustion in thermal power plants, has been widely used in construction industry as partial replacement for Portland cement (PC). Due to environmental protection requirements, it became an imperative to increase the replacement rate of FA. Use of high volume fly ash (HVFA) binders, in which more than 50% of PC is replaced by FA, brings many ecological benefits (reduced pollution and energy consumption related to PC production, reduced waste generation, and preservation of natural resources). However, an increase of FA content in a binder can cause worsening of some of the properties of the binder, and reduction of early compressive strength and prolongation of setting time are of the greatest concern. These properties of HVFA binders can be improved by chemical activation of the binder. In this paper, three selected inorganic activators (Na2SO4, Na2CO3, and Na2SiO3) were used for chemical activation of HVFA binder (70 mas.% of FA and 30 mas.% PC). FA was mechanically activated prior to binder synthesis. Effects of the activators on the hydration of the HVFA binders were examined by isothermal calorimetry, X-ray diffraction, and thermogravimetric analyses. Influence of the chemical activation on the properties of the HVFA binders was analyzed by determination of setting time and compressive strength. The results showed that the chemical activators used in this work accelerated reactions of both PC and FA, which lead to shortened setting times and increased early compressive strength of the binders. The HVFA binder synthesized with sodium silicate as chemical activator had the best properties
Nutrients and soil structure influence furovirus infection of wheat
Get PDFSoil-borne wheat mosaic virus (SBWMV) and Soil-borne cereal mosaic virus (SBCMV), genus Furovirus, family Virgaviridae, cause significant crop losses in cereals. The viruses are transmitted by the soil-borne plasmodiophorid Polymyxa graminis. Inside P. graminis resting spores, the viruses persist in the soil for long time, which makes the disease difficult to combat. To open up novel possibilities for virus control, we explored the influence of physical and chemical soil properties on infection of wheat with SBWMV and SBCMV. Moreover, we investigated, whether infection rates are influenced by the nutritional state of the plants. Infection rates of susceptible wheat lines were correlated to soil structure parameters and nutrient contents in soil and plants. Our results show that SBWMV and SBCMV infection rates decrease the more water-impermeable the soil is and that virus transmission depends on pH. Moreover, we found that contents of several nutrients in the soil (e.g. phosphorous, magnesium, zinc) and in planta (e.g. nitrogen, carbon, boron, sulfur, calcium) affect SBWMV and SBCMV infection rates. The knowledge generated may help paving the way towards development of a microenvironment-adapted agriculture
Size Effect Assessment of KJc Experimental Data Using the Two-Step-Scaling Method
Get PDFThe phenomenon of ductile-to-brittle transition (DBT) in ferritic steels, widely used in design of nuclear reactor pres-sure vessels, has been a pervasive semi-centennial research topic. Due to the extremely pronounced experimental data scatter, the statistical approach to characterization of this problem has become inevitable from the earliest analyses. In the present study, the fracture toughness parameters derived from the EURO fracture toughness dataset for 22NiMoCr37 reactor steel are used with the aim to explore the utility of the recently proposed two-step-scaling method. Two widely different temperatures (-154 °C and -91 °C; belonging to the lower shelf and the DBT transition regions of fracture toughness, in respect) are selected to demon-strate the accuracy of extrapolation and interpolation of the fracture toughness CDF (cumulative distribution function) and the pertinent issues related to the method application. The fracture toughness measure used is the critical value of the stress intensity factor used in the master curve KJc (MPa√m). The obtained predictions are in good agreement with the experimental results and well within the inherent experimental data scatter. The prediction of the fracture toughness CDF obtained by extrapolation using the novel two-step-scaling method is reasonably conservative