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Ambrozija (Ambrosia artemisiifolia L.) je invazivna korovna vrsta na području Hrvatske, ali i ostatku Europe. Uspješnost prilagodbe na različite okolišne uvjete omogućili su ovoj vrsti visoku rasprostranjenost i visoku brojnost populacije u gotovo svim dijelovima Hrvatske. Inter-populacijska varijabilnost jedna je od karakteristika ove vrste, a ostvaruje se u različitim morfološkim i funkcionalnim svojstvima ambrozije s različitih lokaliteta (populacija). Morfološka varijabilnost sjemena ili sjemenski polimorfizam je pojava formiranja različitog sjemena unutar same biljke ovisno o poziciji sjemena na majčinskoj biljci, između dviju jedinki unutar iste populacije, ali i između jedinki različitih populacija. Na području kontinentalne Hrvatske, promatrana je morfološka varijabilnost sjemena između različitih populacija ambrozije s deset lokaliteta kontinentalne Hrvatske: Badljevina, Nova Bukovica, Bošnjaci, Šljivoševci, Ivankovo, Čazma, Johovec, Dubrovčak Lijevi, Lijeva Martinska Ves i Nevinac, gdje ambrozija redovito zakorovljuje okopavinske usjeve. Za svaku populaciju izračunate su mase 1000 roški (sjemenki) i utvrđena je dimenzija pojedinačnog sjemena. Raspon mase 1000 roški kretao se od 2,39 g do 5,56 g. Duljina roške kretala se u rasponu od 3,65 mm do 4,16 mm, dok se širina roške kretala u rasponu od 1,87 mm do 2,15 mm. Utvrđena je inter-populacijska varijabilnost između populacija. Koeficijent varijabilnosti duljine kretao se u rasponu od 8,8 % do 13,4 %, dok se koeficijent varijabilnosti širine kretao u rasponu od 10,3 % do 14,3 %. Utvrđena je slaba varijabilnost između populacija što potencijalno može značiti i razliku u stupnju dormantnosti i klijavosti. Ova morfološka mjerenja sjemena ambrozije na području Hrvatske pružaju osnovu za daljnja istraživanja morfološke i funkcionalne varijabilnosti kao doprinos boljem poznavanju biologije ove invazivne vrste

Weeds can be one of the most severe threats to crop production, especially when they are widespread and highly adaptable. Part of the adaptive strategy of plants is the ability to germinate in different conditions. Germination is the first developmental phase of plant life and is fundamental for its establishment. In this work, the germination of two populations of

Photocatalytic degradations of tricyclic antidepressive amitriptyline (AMI) in aqueous solutions under UV irradiation were performed using TiO2 and TiO2/WO3 coatings, as photocatalysts. Coatings were formed on a pure titanium substrate using plasma electrolytic oxidation (PEO). The effects of chosen synthesis parameters on structural properties of prepared coatings have been investigated using micro-Raman spectroscopy and non-contact atomic force microscopy. Raman scattering measurements showed that coatings contain different amounts of crystalline anatase TiO2 and monoclinic WO3−x phases, as well as amorphous and/or disordered phases of both oxides. Also, results indicated that coatings’ surface become more disordered and inhomogeneous with increasing duration of the PEO. The coating T/W(45 s) prepared during 45 s of PEO has shown the highest efficiency in the UV-driven removal of AMI. T/W(45 s) showed slightly decrease in photodegradation efficiency after four successive runs. The results showed that the degradation of AMI led to the formation of ionic by-products (nitrite, nitrate, ammonium ion, acetate, and formate), whereas degree of mineralization was the highest (38.8%) using coating T/W(45 s) after 120 min of irradiation. Also, there was no significant toxicity observed after irradiation of AMI solutions using different coatings on four mammalian cell lines: rat hepatoma, mouse neuroblastoma, human colon adenocarcinoma, and human fetal lung.

Background The common weeds Echinochloa crus-galli L. and Setaria glauca L. were studied for their sensitivity to aqueous extracts or dry biomass of the following cover crops (CCs): Brassicaceae (Sinapis alba, Raphanus sativus var. Oleiformis, Camellina sativa), Fagopyrum esculentum and Guizotia abyssinica. Results Treating E. crus-galli with aqueous extracts of mixed CCs or individual brassica CC significantly reduced germination. Treating S. glauca with aqueous extracts of C. sativa or G. abyssinicia reduced germination. Aqueous extracts of all CCs significantly reduced radicle length of E. crus-galli and S. glauca, with C. sativa and mixed CCs showing the greatest effect. Aqueous extracts of nearly all CCs delayed start and middle germination of E. crus-galli and S. glauca, with S. alba and R. sativus showing the strongest effects. Aqueous extracts of Brassicaceae leaf and flower significantly reduced germination, coleoptile length, radicle length and seedling biomass of E. crus-galli and S. glauca. Brassicaceae leaves and flowers contained higher phenolics than other tissues. Adding 4 or 8% S. alba and R. sativus dry powder to soil significantly reduced growth of E. crus-galli and S. glauca; even concentrations of 1% measurably slowed growth of E. crus-galli. Conclusions Brassicaceae may be allelopathic to S. glauca and E. crus-galli. Aqueous extracts of leaves and flowers showed greater phytotoxic activity than other tissues and also contained more phenolics. Therefore Brassicaceae CCs may be most effective against S. glauca and E. crus-galli if incorporated into soil during their flowering stage. © 2020 Society of Chemical Industry.

A size–strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO2)-based nanocomposites with carbon (C) was carried out and the results compared with those of a similar sample free of carbon. The crystal structures and microstructures of anatase and brookite, as well as their relative abundance ratio, have been refined from XRPD data by the Rietveld method (the low amount of carbon is neglected). The XRPD size–strain analysis resulted in reliable structure and microstructure results for both anatase and brookite. The experimental Raman spectra of all the samples in the region 100–200 cm−1 are dominated by a strong feature primarily composed of the most intense modes of anatase (Eg ) and brookite (A 1g ). The anatase crystallite sizes of 14–17 nm, estimated by XRPD, suggest the application of the phonon confinement model (PCM) for the analysis of the anatase Eg mode, whereas the relatively large brookite crystallite size (27–29 nm) does not imply the use of the PCM for the brookite A 1g mode. Superposition of the anatase Eg mode profile, calculated by the PCM, and the Lorentzian shape of the brookite A 1g mode provide an appropriate simulation of the change in the dominant Raman feature in the spectra of TiO2-based nanocomposites with carbon. Raman spectra measured in the high-frequency range (1000–2000 cm−1) provide information on carbon in the investigated nanocomposite materials. The results from field-emission scanning electron microscope (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy and nitrogen physisorption measurements support the XRPD and Raman results.

М30 М34 Structural and microstructural properties of TiO2-based nanocomposites with carbon black (C), synthesized by sol-gel-hydrothermal method, have been studied by XRPD and Raman scattering. Detailed size-strain analyses of XRPD and Raman scattering results are presented in order to investigate the influence of C content on brokite and anatase phase formation. The XRPD size-strain analyses have resulted in reliable structure and microstructure results for both anatase and brookite and their relative abundance ratio has been refined by Rietveld method. The brookite and anatase crystallite sizes are estimated by XRPD at ~ 27–29 and 14–17 nm, respectively. The Raman spectra of all samples are dominated by the most intensive modes of anatase (Eg) and brookite (A1g). The analysis of anatase Eg mode by PCM (Phonon Confinement model) has revealed partial compensation of phonon confinement due to anatase nanocrystallite size and tensile deformation of anatase lattice. The refined unit cell parameters obtained from XRPD have shown that C atoms did not enter in the significant amounts into brookite and anatase crystal structures. On the other side, the Raman spectra have revealed features assigned to carbon. The results of both analyses imply that the presence of carbon could influence the formation of brookite and anatase phase in the TiO2-based nanocomposites synthesized by the hydrothermal method.

The formation of the crystalline organic polymer (OP) islands on top of double perovskite ferromagnetic La2Ni1–xMn1+xO6 (x = 0.4) thin films by RF sputtering is reported. The presence of randomly ramified organic polymer islands for film grown on top of SrTiO3 and LaAlO3 substrates suggest the fractal growth. The stability of fractal OP islands is tested by an in-situ oxygen annealing process as function of the annealing temperature. The evolution of the fractal structure of OP islands is followed in parallel with the evolution of structural and magnetic properties of LNMO thin films. The modification of the manganese valence state due to the presence of organic polymer fractals is studied by means of X-ray photoemission microscopy., This work has received funding from the European Union's Horizon 2020 research and innovation under the Marie Sklodowska-Curie grant agreement No. 645658 (DAFNEOX Project). A.P. and Z.K. thank Senzor-INFIZ (Serbia) for the cooperation provided during their respective secondments. E. P.-M. acknowledge financial support from the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centers of Excellence in R&D (CEX2019-000917-S), and project MAT2015-71664 and SPINCURIOX (RTI2018-099960-B-I00). M. Š. and Z. K. acknowledge the support of the Serbian Ministry of Education, Science and Technological Development (Projects No III45018). This work has been performed in the framework of the PhD program of the Universitat Autonoma de Barcelona (UAB).

The surface morphology and structure of zinc oxide thin films play a key role in many applications such as chemical sensors and photocatalysts. In this study, ZnO thin films are prepared on Si/SiO2 substrates by spin-coating sol–gel technique. New element in the films preparation is the application of drying with hot air flow (Th= 90–95 °C), as first step of the drying procedure, followed by furnace drying as second step. It is shown that hot air drying has significant influence on the films properties. It reduces the internal stress, strongly affects the films surface morphology, gives assistance to the effusion of organic remains and results in a better crystallinity and lower defect density in the as-prepared films when compared with the films prepared by furnace drying only. Besides, first data on the modification of sol–gel ZnO films by post-deposition irradiation with a nanosecond infrared laser are obtained, giving an alternative to the standard furnace annealing. They indicate that laser irradiation of as-prepared ZnO films gives rise to certain improvement in crystal structure and slight increase in crystallite size, followed by the increase of micro-strain. It also reduces the number of defects playing role of non-radiative recombination centers, as well as the size and density of small cracks and pores on the surface of as-prepared films.

A size-strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO

Photocatalytic activity of titania–based photocatalysts doped with 1% La has been tested in UVA radiation-induced degradation of two β-blockers – metoprolol tartrate (MET) and propranolol hydrochloride (PRO). Photocatalysts have been synthesized by sol–gel process followed by calcination at various temperatures in the range of 450–750 °C. The great impact of calcination temperature on the structural, compositional and morphological properties of prepared catalysts has been revealed by XRPD, SEM, BET and Raman scattering measurements. Doped catalysts calcined at 450–650 °C, with dominant anatase phase and developed mesoporous structure, have displayed higher photocatalytic performance than much less porous samples calcined at 700–750 °C, with sodium hexatitanate as dominant phase. Also, La-doped anatase sample has shown higher efficiency in degradation of MET and PRO in comparison with the efficiency of undoped TiO2 nanopowders calcined at same temperatures. The quenching effects of various scavengers suggest that the major role in degradation of MET may be attributed to reactive radicals, whereas photogenerated holes are mainly responsible for degradation of PRO. Applying density functional theory (DFT) calculations, we analyzed fundamental structural and electronic properties (total and polar surface areas, frontier molecular orbitals, optoelectronic properties and average local ionization energy surfaces) of MET and PRO molecules, which are of significance for the understanding of more effective degradation of PRO in comparison with MET. Keywords: β-blocker, Photocatalysis, Anatase, La-doping, Density functional theory (DFT), Average local ionization energy (ALIE)

Homogeneous films from SiOx (x = 1.2, 1.3) were deposited on crystalline Si substrates by thermal evaporation of silicon monoxide in vacuum. A part of the films was further annealed at 1000 °C to grow Si nanocrystals in a silicon dioxide matrix. Homogeneous and composite films with initial x = 1.2 were irradiated by 20-MeV electrons at a fluence of 3.6 × 1015 electrons/cm2 and the effect was compared with that caused by irradiation of films with x = 1.3 at much lower fluence of 2.4 × 1014 electrons/cm2. Transmission electron microscopy, infrared transmission and Raman spectroscopies and spectroscopic ellipsometry were used to get information about the SiOx films composition, nanoparticle crystallinity and space distribution as well as for electron-beam induced changes in the nanocrystal size. The infrared data have indicated that electron irradiation with 3.6 × 1015 electrons/cm2 induced phase separation in the homogeneous films with x = 1.2. Not only silicon nanocrystals but also a small amount of amorphous silicon phase have been detected in the composite films before and after electron irradiation. Nanocrystallite size decrease induced by the electron beam irradiation at a fluence of 3.6 × 1015 electrons/cm2 has been assumed on the basis of the observed changes in the effective refractive index, extinction coefficient and nanocrystallite volume fraction in the composite films.

Background and purpose: Abutilon theophrasti Medik (velvetleaf) is an invasive plant well spread in Croatia as noxious weed species. The aim of this study was to provide morphological, phenological and reproductive information of velvetleaf grown under various densities: 2, 5, 10 and 20 plants m-2. Material and methods: The field experiment was conducted in 2014 at University of Zagreb Faculty of Agriculture as complete randomized blocks design. Throughout the vegetation morphological (hypocotyl and epicotyls length, number of leaves and branches, plant height, shoot dry weight and diameter), phenological (beginning of flowering end of flowering and first capsule formation; GDD to beginning of flowering end of flowering and first capsule formation) and reproductive (capsules plant-1, seed capsules -1, seeds plant-1, seeds m-2, 1000 seeds weight and germinability) characteristics were measured. Results and conclusion: Mostly all morphological and reproductive characteristics were significantly affected by plant density. Increase of velvetleaf competition from 2 to 20 plants m-2 hasreduced number of capsule and consequently almost five fold decreased seed production per plant. However, plants which have been growing at densities > 5 plants m-2 produced in average 50% more seeds per land area than plants at the lowest density. Low germinability at harvest (2%) and six month later (15%) indicate on primary dormancy and possibility for longevity in soil if plants are left uncontrolled in the field. In contrast to morphological and reproductive changes, plants in high density did not showed increasing growing degree days requirements.

The anodic oxidation method is applied for preparation of TiO2 nanotube (NT) arrays on Ti6Al4V alloy substrates. The NTs were of four different diameters (60, 65, 80 and 120 nm) and wall thicknesses in the range 8–14 nm. The as-prepared samples were characterized and then annealed at 450 °C in air for 2 h. The surface morphology of the samples is characterized by field emission scanning electron microscopy which reveals uniformly distributed nanotube arrays over the substrate. Raman scattering measurements show that the NTs in as-prepared samples are amorphous. In annealed samples rutile phase and a small amount of anatase phase are detected by both Raman scattering and X-ray diffraction methods. It is assumed that the rutile phase is related to a TiO2 film with rutile structure formed during the annealing between NTs and alloy substrate. The retarded formation of anatase phase is connected with inclusion in the TiO2 nanotubes of external atoms coming from the substrate. The amount and crystallinity of anatase phase decreases with decreasing nanotube diameter and/or wall thickness which is assigned to size-induced increase of the NT crystallization temperature. Investigations of the optical response of the samples to ethanol vapors at room temperature reveal relations between the NT size and their ethanol sensitivity. The response of as-prepared nanotube arrays increases with decreasing nanotube diameter while in the annealed samples an opposite trend is observed. The size dependence seen for as-prepared samples is related to an increase of the total adsorbing surface with decreasing NT diameter. The result obtained for the annealed samples is assigned to annealing induced changes in the morphology and composition of the internal surface of NTs.

Mesoporous anatase nanopowders were doped with 0.05−0.5 mol% of W6+, in order to obtain more efficient photocatalyst than TiO2 Degussa P25 in the degradation of amitriptyline (AMI) under simulated solar irradiation (SSI). Dominant XRPD peaks were ascribed to anatase phase, with additional peaks which could correspond to brookite, TiO2 bronze and sodium titanate, Na2Ti9O19. The Raman scattering measurements have confirmed anatase as dominant phase, with broad Raman feature at ~270 cm−1 possibly related to Ti–O–Na stretching vibration. All W-doped nanopowders have shown enhanced adsorption and higher efficiency in photodegradation of AMI in comparison to TiO2 Degussa P25 under the same conditions. The catalyst doped with 0.4 mol% of W6+, which has shown the highest efficiency in degradation of AMI under SSI, has also been tested in degradation of alprazolam (ALP). The effect of substrate type (AMI and ALP), catalyst loading, and initial substrate concentration on photocatalytic degradation using SSI was examined. The identification of the species responsible for the photocatalytic degradation of AMI and ALP by the catalyst doped with 0.4 mol% of W6+ was performed in the presence of various scavengers under SSI. The major role in degradation of AMI may be attributed to hydroxyl radicals, whereas superoxide anion radicals, singlet molecular oxygen and hydroxyl radicals contribute to degradation of ALP.

Nitrogen (N)-doped SrTiO3 /pristine SrTiO3 powders were synthesized by three different methods namely hydrothermal, sol-gel route and solid state reaction respectively. The influence of synthesis route, thermal treatment atmosphere and N doping on the properties and photo-catalytic efficiency of the prepared samples was analyzed. The investigation shows that N doping causes the narrowing of the band gap with about 1 eV. The synergy of the structure, texture and morphology and especially N doping explains high methyl orange (MO) degradation efficiency of 100% within 1 h of irradiation for the N doped SrTiO3 obtained by sol-gel route with the aid of non-ionic triblock copolymer (Pluronic P123) as a structure-directing and thermally treated under nitrogen atmosphere.

Several cover crops (CCs) exert allelopathic effects that suppress weed growth. The aim of the present study was to evaluate the effects of aqueous extracts containing different concentrations [0, 0.5, 1, 2.5, 5, 7.5 and 10% (w/v)] of Brassicaceae CCs (Sinapis alba, Raphanus sativus, Camellina sativa) and of the CCs Fagopyrum esculentum and Guizotia abyssinica on germination and early growth of Ambrosia artemisiifolia L. The allelopathic effects were species and concentration-dependent. C. sativa, for example, caused the greatest potential to inhibit germination, shoot, radicle length and fresh seedling weight, whereas S. alba and R. sativus inhibited germination and early growth of A. artemisiifolia only at concentrations ≥ 7.5%. In contrast, no inhibition was observed when aqueous extracts of F. escultneum and G. abyssinica were added at any of tested concentration. Liquid chromatography-tandem mass spectrometry detected 15 phenolic compounds in Brassicaceae CCs with the highest content (µg/g) of vanillin (48.8), chlorogenic acid (1057), vanilic acid (79), caffeic acid (102.5) and syringic acid (27.3) in C. sativa. Our results suggest that C. sativa is the most allelopathic CCs and that the fruits of C. sativa are the plant organs richest in allelochemicals.

Alopecurus myosuroides Huds. is an important pinoxaden-resistant grass weed in many countries of Europe. Recently, the low efficacy of pinoxaden was reported in winter cereals in Croatia, but a preliminary dose–response trial showed no herbicide resistance for the investigated weed population. Therefore, a two-year experiment was conducted under greenhouse conditions to determine the efficacy of various pinoxaden doses (20, 40 and 80 g a.i. ha−1) on weed visual injuries and biomass reduction after herbicide application at different growth stages. As expected, the maximum weed biomass reduction (97.3%) was achieved by applying the highest dose (80 g a.i. ha−1) at the earliest growth stage (ZCK 12–14). A pinoxaden dose of 20 g a.i. ha−1 resulted in satisfactory weed biomass reduction (88.9%) only when applied at ZCK 12–14. The recommended dose (40 g a.i. ha−1) also provided sufficient weed control up to the growth stage ZCK 21–25. Slightly delayed (ZCK 31–32) application of the recommended dose brought about a low weed biomass reduction (60.1%). Double than the recommended dose also failed to provide satisfactory weed control at the advanced weed growth stages (ZCK 31–32 and ZCK 37–39). Thus, reported low efficacy of pinoxaden is most likely because of delayed herbicide application when A. myosuroides is overgrown.

The efficacy of weed management depends on the correct control timing according to the seedling emergence dynamics. Since soil temperature and soil moisture are two main factors that determine weed germination, the hydrothermal time model can be used to predict their emergence. The aim of this study was to estimate the base temperature (Tb) and base water potential (Ψb) for germination of Chenopodium album, Amaranthus retroflexus, Setaria pumila and Panicum capillare collected from fields in continental Croatia and then to compare these values with those of Italian populations embedded in the AlertInf model. Germination tests were performed at seven constant temperatures (ranging from 4 to 27°C) and eight water potentials (0.00 to - 1.00 MPa). Estimated Tb and Ψb were 3.4°C, -1.38 MPa for C. album, 13.9°C, -0.36 MPa for A. retroflexus, 6.6°C, -0.71 MPa for S. pumila and 11.0°C, -0.87 MPa for P. capillare, respectively. According to the criterion of overlap of the 95% confidence intervals, only Tb of C. album, and Ψb of A. retroflexus were similar between Croatian and Italian populations. Further field experiments should be conducted in the Croatian field to monitor weed emergence patterns of C. album and to calibrate the AlerInf equation parameters.

Echinochloa crus-galli (L.) P. Beauv. is the most common monocotyledonous weed in maize crops in Croatia. Crop–weed interference is influenced by weed emergence patterns, and knowledge of the timing of weed emergence is crucial for the development of an efficient integrated weed-management program. Therefore, two-year field experiments were conducted in a maize crop sown in early May in continental Croatia to determine the emergence pattern of E. crus-galli from natural seedbank. In laboratory studies, the estimated base temperature and base water potential for the Croatian ecotype of E. crus-galli were 10.8 °C and −0.97 MPa, respectively. Then, the estimated germination parameters were compared with the values embedded in the AlertInf model from Italy (Veneto) to calibrate this hydrothermal model. The estimated hydrothermal units were around 28 for the onset (10%) and 93 for the middle (50%) emergence of E. crus-galli. Our findings showed that the AlertInf model satisfactorily simulated the emergence of E. crus-galli in maize crop in Croatia (EF = 0.97 in 2019 and 0.98 in 2020), indicating its potential use in other geographical areas

The common weeds Echinochloa crus-galli L. and Setaria glauca L. were studied for their sensitivity to aqueous extracts or dry biomass of the following cover crops (CCs): Brassicaceae (Sinapis alba, Raphanus sativus var. Oleiformis, Camellina sativa), Fagopyrum esculentum and Guizotia abyssinica.Treating E. crus-galli with aqueous extracts of mixed CCs or individual brassica CC significantly reduced germination. Treating S. glauca with aqueous extracts of C. sativa or G. abyssinicia reduced germination. Aqueous extracts of all CCs significantly reduced radicle length of E. crus-galli and S. glauca, with C. sativa and mixed CCs showing the greatest effect. Aqueous extracts of nearly all CCs delayed start and middle germination of E. crus-galli and S. glauca, with S. alba and R. sativus showing the strongest effects. Aqueous extracts of Brassicaceae leaf and flower significantly reduced germination, coleoptile length, radicle length and seedling biomass of E. crus-galli and S. glauca. Brassicaceae leaves and flowers contained higher phenolics than other tissues. Adding 4 or 8% S. alba and R. sativus dry powder to soil significantly reduced growth of E. crus-galli and S. glauca; even concentrations of 1% measurably slowed growth of E. crus-galli.Brassicaceae may be allelopathic to S. glauca and E. crus-galli. Aqueous extracts of leaves and flowers showed greater phytotoxic activity than other tissues and also contained more phenolics. Therefore Brassicaceae CCs may be most effective against S. glauca and E. crus-galli if incorporated into soil during their flowering stage. © 2020 Society of Chemical Industry.

Poljska ljubica (Viola arvensis Murr.) jednogodišnja je vrsta koja zakorovljuje usjeve gustog sklopa te nasade bobičastog voća i povrćarskih kultura. Potječe s prostora Euroazije, a zbog svojstva adaptibilnosti proširila se i na ostale kontinente. Često je moguća zamjena s vrstom V. tricolor L. (maćuhica) od koje se razlikuje po boji cvjetova i obliku gornjih listova. Razmnožavanje V. arvensis generativno je. U laboratorijskim uvjetima najveća klijavost ostvaruje se pri temperaturi od 15 °C u trajanju od 8 sati te pri temperaturi od 5 °C u trajanju od 16 sati. Preferira pjeskovita tla reakcije od blago kisele do lužnate. Tolerantna je na zasjenjivanje i sušu. Prezimljuje u formi rozete, a visinom biljka može dosegnuti prosječno 30 cm. Zbog niskog habitusa izravne štete uzrokovane korovnom vrstom V. arvensis nisu toliko značajne koliko neizravne koje se javljaju nakon žetve usjeva kada biljno tkivo zahvaćeno pri žetvi usjeva može utjecati na povećanje vlage sjemena usjeva. V. arvensis vrsta je koja se prilagodila utjecaju čovjeka te se uspješno razvija na obrađivanim tlima. Forma rozete smatra se tolerantnom prema primjeni herbicida te je zbog toga otporna na primjenu kemijskih mjera suzbijanja.

Herbicidi inihibitori acetolaktat sintaze (ALS) koriste se u većini ratarskim i povrtnih usjeva te višegodišnjim nasadima za suzbijanje jednogodišnjih i višegodišnjih korovnih vrsta. Njihova široka upotreba, kao i povlačenja velikog broja herbicida s tržišta EU-a, doveli su do pojave rezistentnih biotipova korova na ove herbicide. Zbog gorućeg problema rezistentnosti svih štetnika na pesticide, Ministarstvo poljoprivrede financira projekt „Program monitoringa rezistentnosti štetnih organizama na sredstva za zaštitu bilja u Republici Hrvatskoj 2018-2020“ u sklopu kojeg su i u našoj zemlji potvrđene rezistentne populacije dvije korovne vrste: Sorghum halepense i Ambrosia artemisiifolia. Sustavnim provođenjem integriranog suzbijanja korova potrebno je spriječiti daljnje širenje rezistentnih populacija, Acetolactate Synthase Herbicides (ALS) are the most frequently used herbicides in arable and permanent crops to control annual and perennial weed species. Their widespread use and the withdrawal of a large number of herbicides from the EU market have led to the emergence of herbicide-resistant weeds. Due to the urgent problem of resistance of all pests to pesticides, the Ministry of Agriculture is funding the project "Resistance Monitoring Programme Harmful Organisms for Pesticides in the Republic of Croatia 2018-2020", which will confirm the resistance of two weed species Sorghum halepense and Ambrosia artemisiifolia on ALS herbicides. The systematic implementation of integrated weed control requires preventing the further spread of resistant populations.

Rod Panicum obuhvaća veći broj vrsta (370 - 600) raširenih u svijetu, a podrijetlom je iz tropskih i suptropskih krajeva. U RH su prisutne četiri vrste iz ovog roda: Panicum capillare L., Panicum dichotomiflorum Michx., Panicum miliaceum L. i Panicum riparium H. Scholz od kojih se prve tri pojavljuju kao korovi okopavinskih usjeva. Panicum capillare i Panicum dichotomiflorum invazivne su vrste na području RH: P. capillare prvi put zabilježen u RH 60-ih godina, Panicum dichotomiflorum 70-ih, a Panicum miliaceum 90-ih godina prošlog stoljeća. Ovisno o različitom vremenu pojave na prostoru RH, u usjevima je kao korovna vrsta najrasprostranjeniji P. capillare kojeg slijedi P. dichotomiflorum te potom P. miliaceum . Navedene su vrste prema životnom ciklusu jednogodišnje te se šire isključivo sjemenom. Sjeme se najčešće širi poljoprivrednim strojevima i oruđem, ali je znatno prisutna epizoohorija te anemohorija . Za razliku od ostalih monokotiledonih korovnih svojti čije sjeme u banci sjemena brzo gubi klijavost, sjeme P. dichotomiflorum može sačuvati klijavost i do 20 godina, čineći perzistentnu banku sjemena u tlu. Sve su navedene vrste kasnoproljetne s temperaturnim minimumom za klijanje od 10 °C i više te optimumom od 30 °C. Suzbijanje vrsta roda Panicum najčešće se provodi herbicidima. Ipak, zbog kasnog nicanja u usporedbi s drugim korovnim travama u kukuruzu, često izbjegnu aplikaciju herbicida, što se potom pogrešno tumači lošom učinkovitosti. No, poznavanjem biologije i ekologije vrsta moguća je uspješna integrirana zaštita te primjena nekemijskih mjera poput zasjenjivanja, odnosno korištenja pokrovnih kultura, smanjenja razmaka sjetve te korištenja plodoreda i obrade tla.

Ambrosia artemisiifolia L. napasna je korovna vrsta poljoprivrednih i nepoljoprivrednih staništa. Sjeme A. artemisiifolia u trenutku osipanja posjeduje srednji tip primarne fiziološke dormantnosti koja onemogućuje klijanje. U poljskim uvjetima prekid ovog tipa dormantnosti događa se zimi zbog prolaska sjemena kroz razdoblje niskih temperatura i vlažnih uvjeta. Imitacija hladnoga razdoblja u laboratorijskim pokusima prekidanja dormantnosti metoda je koja se primjenjuje za poticanje klijavosti sjemena. Poznavanje promjena u stupnju dormantnosti tijekom hladnog skladištenja može doprinijeti odabiru odgovarajuće metode prekidanja dormantnosti. Cilj je ovoga istraživanja bio odrediti razdoblje unutar kojeg dolazi do prekidanja dormantnosti ambrozije u uvjetima hladnog skladištenja (4 °C). Sjeme ambrozije prikupljeno je s devet lokacija kontinentalne Hrvatske te je na svakoj populaciji proveden test klijavosti u različitim vremenskim intervalima hladnog skladištenja (0, 1, 3, 6 i 11 mjeseci). Rezultati pokazuju da svježe sakupljeno sjeme nije u mogućnosti proklijati. Tek nakon šest mjeseci hladnog skladištenja klijavost se značajno povećala i ovisno o populaciji iznosila od 34 do 67 %. Međutim duže hladno skladištenje (11 mjeseci) u tri od devet populacija ambrozije dovelo je do smanjenja klijavosti od 13 do 21 %, a u ostalih populacija klijavost je ostala jednaka. Samo je u jednoj populaciji hladnim skladištenjem došlo do porasta klijavosti. Rezultati istraživanja pokazuju da je hladno skladištenje sjemena u trajanju od šest mjeseci djelotvorna metoda prekidanja dormantnosti sjemena ambrozije. Kako je ustanovljena značajna razlika u klijavosti između devet istraživanih populacija ambrozije nakon 3, 6 i 11 mjeseci hladnog skladištenja, potrebno je u budućim istraživanjima utvrditi razloge ove interpopulacijske varijabilnosti.

The aim of the research was to determinate the degree of variation in morphological (seed weight) and functional polymorphism (final germination, dormancy, seed mortality and germination dynamic) within two seed populations of Ambrosia artemisiifolia L. Seeds were collected separately from 20 plants/population in Jastebarsko (45°40'18˝N; 15°39'03˝E), population-J and Popovača (45°34´1˝N; 16°40´43˝E), population-P in 2014. Seed weight of J and P populations had weak variability (CV-J = 18.2%, CV-P= 29.8%) with an average of 4.05 g (J) and 4.54 g (P). Estimated variability was strong for amount of death seeds in the J (CV = 67.6%), but weak for geminated (CV = 4.9%) and moderate for dormant seeds (CV = 51.0%). Variability within P population was moderate for both germinated and dead seeds (CV = 34.5%; 34.1%), while variability within amount of dormant seeds was weak (CV = 14.2%). Variability in medium germination (T50) was relatively low for both experimental populations (CV – J = 12.0%; CV – P = 22.4%). Despite determined intrapopulation variation, degrees of variability between researched parameters (final germination, dormancy and medium germination – T50) were weak or moderate and therefore acceptable for further experiment base on seed testing., Cilj istraživanja bio je utvrditi stupanj morfološke (masa sjemena) i funkcionalne (klijavost, dormantnost, smrtnost sjemena i dinamika klijanja) varijabilnosti unutar dvije populacije sjemena korovne vrste Ambrosia artemisiifolia L. (ambrozija) sakupljene u sjeverozapadnom dijelu Hrvatske: Jastrebarsko (45 ° 40'18˝N; 15 ° 39'03˝E), populacija-J i Popovača (45 ° 34´1˝N; 16 ° 40´43˝E), populacija-P. Prikupljeno je sjeme s 20 biljaka/populaciji u listopadu 2014. Rezultati istraživanja ukazuju na slabu varijabilnost (CV-J = 18,2%, CV-P = 29,8%) mase 1 000 sjemenki s prosječnom masom od 4,05 g (J) i 4,54 g (P). Intrapopulacijska varijabilnost bila je relativno visoka za udio mrtvog sjemena u populaciji-J (CV = 67,6%), ali vrlo slaba za udio klijavog (CV = 4,9%) te umjerena za udio dormantnog sjemena (CV = 51,0%). Varijabilnost unutar populacije-P bila je umjerena za udio klijavog i mrtvog sjemena (CV = 34,5%; 34,1%), a relativno slaba za udio dormantnog sjemena (CV = 14,2%). Dinamika klijanja (T10, T50 i T90) obje populacije bila je slabo ili umjereno varijabilna. Sredina klijanja (T50) bila je relativno slabo varijabilna za obje istraživane populacije (CV - J = 12,0%; CV - P = 22,4%).

Bijela loboda (Chenopodium album L.) jednogodišnji je širokolisni korov iz porodice lobodnjača (Chenopodiaceae). Podnosi vrlo različite klimatske uvjete i različite tipove tala zbog čega se ubraja među pet najrasprostranjenijih korovnih biljaka u svijetu. U Hrvatskoj je treći najučestaliji korov okopavinskih usjeva. Loboda je kozmopolitska vrsta s arealom rasprostranjenosti od 70° sjeverne do 50° južne geografske širine. Sposobna je prilagoditi se različitim klimatskim uvjetima pa biološki temperaturni minimum (Tb), ovisno o klimatu, varira od 2,0 do 6,0°C. Za područje kontinentalne Hrvatske Tb iznosi 3,4°C. Može nicati u uvjetima visokog vodnog stresa kao i u širokom rasponu pH tla vrijednosti od jako kiselih do alkalnih. Svojom prisutnošću u usjevu,ovisno o vremenu nicanja, gustoći i razvojnom stadiju kulture, znatno utječe na prinos okopavinskih kao i povrtlarskih kultura. Važan je korov u oko 40 poljoprivrednih kultura, a najčešće u šećernoj repi, krumpiru, soji, kukuruzu, suncokretu i jarim žitaricama. Glavna štetnost lobode, ogleda se u direktnim štetama. Važne su i indirektne štete kao npr. otežana žetva, kontaminacija uroda i tla sjemenjem, prenošenje virusnih bolesti na kultivirano bilje i dr. Pelud bijele lobode kod osjetljivih ljudi uzrokuje jake alergijske reakcije.

In this work, Zn(CH3COO)2 ? 2H2O with AgNO3 content from 0 to 6mol% was solvothermally treated at 120?C for 18 h in the presence of poly(vinyl pyrrolidone), ethylene glycol and sodium hydroxide. The structural, microstructural and photocatalytic properties of the unmodified and Ag modified ZnO powders have been investigated by the XRPD, FESEM, TEM, UV-vis, Raman and BET techniques. The Ag modified samples consist of ZnO nanocrystals and metallic Ag on the surface. The average crystallite size of all samples was about 20 nm. The FESEM revealed the uniformity in size and approximately spherical shape of ZnO nanoparticles. The BET data suggest that all prepared samples are mesoporous. All prepared samples showed higher photocatalytic efficiency in the degradation of the Reactive Orange 16 (RO16) azo dye than the commercial ZnO. In addition, Ag modified ZnO powders, especially those with 1.5 and 0.75mol%of Ag, were more efficient than the unmodified one.

The present study estimated the cracking phenomenon in as-plasma-sprayed hydroxylapatite coatings (HACs) after they were being subjected to the severe cutting conditions in the direction perpendicular to the coating/substrate interface. In order to evaluate the effects of substrate preheating on the occurrence of micro-cracks, the HACs were deposited at different initial substrate temperatures (TS = 20, 100 and 200°C). The changes in phase composition and HA splat morphology with TS were observed and were correlated with the cracking occurrence. The results showed that severe cutting conditions introduced a localized cracking in the regions of HACs dominantly attributed to the brittle hydroxyl-deficient amorphous calcium phosphate (ACP) phase. This effect was particularly observable in the HACs deposited without preheating of substrate. On the other hand, the preheating of substrate reduced the presence of micro-cracks and caused insignificant changes in the average local phase composition. In HACs deposited with preheating of substrate, the HA splats (of which HACs are composed) were thinner and recrystallized HA regions seemed smaller in size and more evenly distributed. These results implied potentially important roles of the HA splat formation mechanism on the distribution of ACP and recrystallized HA regions in the as-plasma-sprayed HACs and the cracking resistance of HACs. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 34022]

Abutilon theophrasti is a weed that is spreading worldwide and that has had to adapt to different combinations of environmental conditions. Wide interpopulation variability has been reported regarding dormancy and germination. This variability, controlled by the interaction of genetic diversity and maternal effect, could hinder the adoption of Integrated Weed Management (IWM) tools. A collaborative project was conducted to compare emergence dynamics of 12 European and North American populations under diverse environmental conditions. The main aim was to assess interpopulation variability and explain this according to environmental conditions in the seed collection sites. Seeds were sown at six experimental sites, and seedling emergence was monitored. The AlertInf model was tested to evaluate its ability to predict emergence dynamics of the different populations. A wide interpopulation variability was observed for emergence percentage and dynamics with consistent trends across sites and related to different seed dormancy levels. Populations from Catalonia, Iowa and Minnesota reached higher emergence percentage with earlier and concentrated emergence flushes probably due to low dormancy level, while populations from Croatia, Serbia and Hungary, given their low average emergence percentage, presented high dormancy levels. Good predictive accuracy of AlertInf model was obtained at the different sites, confirming the possibility of adopting it across a wide range of environmental conditions. Achieving a better knowledge of interpopulation variability can allow specific control strategies to be designed, facilitating the replacement of solely herbicide- based management with true IWM.

Sivi muhar (Setaria glauca L. P. Beauv.) uskolisna je korovna vrsta koja se redovito javlja u svim okopavinskim usjevima Hrvatske. Uspješnost ove vrste ogleda se u brzu plodonošenju, velikoj produkciji i dugovječnosti sjemena. Sivi muhar kozmopolit je u područjima umjerenog pojasa s arealom rasprostranjenosti između 55° sjeverne pa sve do 45° južne geografske širine. Sposoban je prilagoditi se različitim klimatskim uvjetima, pa u toplijim klimatima razvija veći, a u hladnijim klimatima manji biološki minimum (Tb). Za područje kontinentalne Hrvatske (Šašinovec) Tb iznosi 6,6 °C, a biološki vodni potencijal (Ψb) iznosi ‐0,71 MPa. Teže podnosi vodni stres, pa se javlja u godinama i područjima s većom količinom padalina. Sivi muhar niče iz plitkog sloja tla, odnosno iz dubine 1 – 5 cm. Odgovaraju mu različiti tipovi tala s pH vrijednošću od 6,1 do 8,0. Kao korovna vrsta na poljoprivrednim površinama Setaria glauca može uspostaviti veliku gustoću po jedinici površine i time uvelike utjecati na prinos poljoprivrednih kultura. Osim direktnih šteta, i indirektno šteti jer se povećavaju troškovi čišćenja uroda, a može biti i alternativni domaćin patogena, uzročnika bolesti usjeva., Yellow foxtail (Setaria glauca L.) is a narrow‐leaved weed species that occurs regularly in all row crops in continental Croatia. The success of this species may be attributed to rapid fruiting, large production of seeds and their longevity. This species is cosmopolitan in temperate zones with an area of distribution ranging from 55 °N to 45 °S latitude. It is able to adapt to different climatic conditions, so in warmer climates it develops higher, while in colder climate lower biological minimum (Tb). For the area of continental Croatia (Šašinovec) estimated Tb is 6.6 ° C, while biological water potential (Ψb) is ‐0.71 MPa. Yellow foxtail hardly tolerates water stress which is why it occurs in years and areas with higher rainfall. This species grows from a shallow layer of soil, ie from a depth of 1 ‐ 5 cm. It grows on different soil types with a pH of 6.1 to 8.0. As a weed species on agricultural land, Setaria glauca can establish a high density per unit area and thus greatly reduce the yield of cultivated crops. In addition to direct damage, this species is also responsible for increasing cleaning costs and may be an alternative host to crop diseases.

Alopecurus myosuroides Huds. (mišji repak) učestala je jednogodišnja uskolisna korovna vrsta u usjevu ozimih žitarica. Povećanim brojem rezistentnih populacija u zapadnoj Europi na različite mehanizme djelovanja herbicida sve se veća važnost pridaje poznavanju biologije i ekologije ove vrste. Nicanje mišjeg repka odvija se u jesen i u proljeće. Veći dio populacije (80 %) ponikne ujesen te je suzbijanje mišjeg repka usmjereno na to razdoblje. Jedinke koje poniknu ujesen naprednije su u razvoju te razvijaju veći broj izbojaka, posljedično i veći broj klasova koji nose sjemenke. Proljetne jedinke češće su alternativni domaćini opasnog patogena Claviceps purpurea. Mišji repak dobro podnosi niske temperature, a niče već na 0 °C (biološki minimum). Biološki vodni potencijal (minimalna količina vode u tlu potrebna za nicanje) za ovu vrstu iznosi ‐1,50 MPa. Za razliku od vrste Apera spica‐venti koja se također pojavljuje u usjevu ozimih žitarica, Alopecurus myosuroides najčešće se pojavljuje na teškim, glinastim tlima s visokim sadržajem vode, a Apera spicaventi niče na lakšim i pjeskovitim tlima. Optimalna je dubina za nicanje mišjeg repka 0 do 2 cm. Zbog toga vrsta predstavlja veći problem u no‐till sustavima obrade, gdje se nerijetko pojavljuje u većoj gustoći. Obrada je jedna od najučinkovitijih nekemijskih mjera suzbijanja mišjeg repka, ali ipak ne i najpouzdanija. Varijabilnosti u učinkovitosti nekemijskih metoda suzbijanja kao što je obrada tla, povezuju se s biologijom vrste (različit stupanj dormantnosti), klimatskim uvjetima i agrotehnikom proizvodnje. Pouzdano i učinkovito suzbijanje postiže se kombinacijom nekemijskih mjera s herbicidima različitog mehanizma djelovanja (antirezistentna strategija)., Alopecurus myosuroides Huds. (black‐grass) is annual weed species in winter cereal crops. With an increasing number of resistant populations in Western Europe on various herbicides mode of action, interest in the biology and ecology of this species has increased. The black‐grass emergence is divided in two phases: autumn and spring emergence. The majority of the population (80 %) emergences in the autumn and the control of blackgrass is focused on this period. Plants emerged during the autumn develop more tillers and consequently a larger number of seed heads with seed. Spring individuals are more likely to be alternative hosts of the pathogen Claviceps purpurea. Blackgrass is a typical winter species and is well adjusted to low temperatures and its base temperature is estimated to 0 °C. The base water potential (the minimum amount of water in the soil needed to promote the germination) for this species is ‐1.50 MPa. Unlike the morphologically similarity to Apera spicaventi which also occurs in winter cereals, Alopecurus myosuroides occurs most in heavy, clay soils with high water content, while Apera spica‐venti emerges in lighter and sandy soils. The optimum soil depth for the black‐grass emergence is 0‐2 cm (surface layer of soil). For this reason, the species is a bigger problem in no‐till processing systems, where it often occurs at higher density. Ploughing is one of the most effective non‐chemical measures to suppress the blackgrass, but is not the most reliable. Variability in the effectiveness of nonchemical methods such as ploughing is associated with the biology of the species (different degree of dormancy), climatic conditions and farming practices. Reliable and effective suppression is achieved by combining nonchemical measures with chemical measures using herbicides with different mode of action (anti‐resistant strategy).

Solanum nigrum L. (crna pomoćnica) jednogodišnji je širokolisni, proljetni korov okopavina, a može se pojaviti i u šumskim sustavima. Odlikuje se velikom produkcijom sjemena koje ima svojstvo dormantnosti i može biti do 40 godina vijabilno u tlu. Za klijanje zahtijeva alternirajuće temperature, uz izmjenu režima svjetlo / mrak, te je klijanje najbolje ako se sjeme nalazi na dubini od 1 cm. U laboratorijskim uvjetima, klijanje se može potaknuti dodavanjem giberelinske kiseline ili nitrata u supstrat. Ovisno o karakteristikama tla, genetici i uvjetima okoliša u kojima se nalazi, može sintetizirati veću količinu toksičnih spojeva zbog čega može doći do trovanja ljudi ili životinja konzumacijom Solanum nigrum L. Ipak se neki izolirani spojevi iz biljke koriste u farmaceutskoj industriji i medicini. Vegetacija korovne vrste S. nigrum započinje u svibnju i traje sve do listopada. Cvjeta i plodonosi do kraja vegetacijske sezone. Jedna biljka tijekom vegetacije može producirati i do 178 000 sjemenka.

The titanium dioxide (TiO2) nanopowders were produced by sol-gel technique from tetrabutyl titanate as a precursor by varying some parameters of the sol-gel synthesis like the temperature (500 and 550 °C) and the duration of the calcination (1.5, 2, and 2.5 h). X-ray powder diffraction (XRPD) results have shown that all synthesized nanopowders are dominantly in anatase phase, with the presence of a small amount of rutile in samples calcined at 550 °C. According to the results obtained by Williamson-Hall method, the anatase crystallite size was increased with the duration of the calcination (from 24 to 29 nm in samples calcined at lower, and from 30 to 35 nm in samples calcined at higher temperature). The analysis of the shift and linewidth of the most intensive anatase Eg Raman mode confirmed the XRPD results. The analysis of pore structure from nitrogen sorption experimental data described all samples as mesoporous, with mean pore diameters in the range of 5-8 nm. Nanopowder properties have been related to the photocatalytic activity, tested in degradation of the textile dye (C.I. Reactive Orange 16), carbofuran and phenol. [Projekat Ministarstva nauke Republike Srbije, br. III45018 i br. ON171032]

The aim of the present study was to investigate the influence of substrate preheating on the structural properties of hydroxyapatite coatings (HACs) deposited by using the high power (52 kW) laminar plasma jet. The deposition experiments were performed within the 20-200 degrees C temperature range at different stand-off distances. The structural properties in the thickness direction and at the surface of the HACs were investigated by using the micro-Raman spectroscopy, scanning electron microscopy coupled with energy dispersive spectrometry, and X-ray powder diffractometry. The deposition without the preheating of the substrate produced HACs with crystallinity gradient in the thickness direction. At the stand-off distance of 80 mm, the preheating of the substrate at 200 degrees C practically eliminated the crystallinity gradient. At distances from the coating/substrate interface shorter than similar to 100 mu m, the increase of crystallinity with the preheating of the substrate was dominantly attributed to the recrystallization of hydroxyl-rich ACP into HA. At longer distances and higher initial substrate temperatures ( GT 100 degrees C), the crystallinity changes were negligible, whereas the recrystallization of hydroxyl-deficient ACP into oxyapatite (OA) was also possible. The X-ray diffractometry indicated the deposition conditions under which a minimum residual stress was achieved. The results of the present study strongly suggested the relation between the ACP - GT HA remystallization process and the bonding strength of the HACs. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

In this work we report on the controlled fabrication of a self-assembled line network in highly epitaxial BiFeO3 thin films on top of LaAlO3 in the kinetically limited grown region by RF sputtering. As previously shown in the case of manganite thin films, the remarkable degree of ordering is achieved using vicinal substrates with well-defined step-terrace morphology. Nanostructured BiFeO3 thin films show mixed-phase morphology. Besides typical formation following (100) and (010) axes, some mixed phase nanodomains are detected also in-between the regular line network. These particular microstructures open a playground for future applications in multiferroic nanomaterials., This work has received funding from the European Union’s Horizon 2020 research and innovation under the Marie Sklodowska-Curie grant agreement No. 645658 (DAFNEOX Project). A.P., V. F. and Z.K. thank Senzor-INFIZ (Serbia) for the cooperation provided during their respective secondments. E. P.-M. acknowledge financial support from the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015- 0496), and project MAT2015-71664 and SPINCURIOX (RTI2018-099960-B-I00). N. L., M. S., Z. K. and Z.V.P. acknowledge the support of the Serbian Ministry of Education, Science and Technological Development (Projects No III45018).