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Uticaj spoljašnjih faktora na klijavost semena ratarskih useva
No full textSeed germination is a complex biological process influenced by a combination of internal and external factors. This paper analyzes the impact of key environmental factors: temperature, water availability, light, pH value, and storage conditions on seed germination, with a particular focus on field crops. Temperature plays a crucial role in enzymatic activity and metabolic processes, with both excessively high and low temperatures negatively affecting germination due to oxidative stress and enzyme inhibition. Water availability is essential for seed rehydration and metabolic activation, while excess moisture can lead to anaerobic conditions that hinder germination. Light influences germination through photoreceptors that regulate hormonal balance, affecting dormancy and growth initiation. Soil pH affects nutrient availability and enzyme activity, with extreme pH levels inhibiting seed metabolism. Finally, storage conditions determine seed viability over time, with high humidity and temperature, accelerating biochemical degradation. Understanding these factors is crucial for optimizing seed germination and improving agricultural productivity, particularly in the context of climate change.Klijanje semena je složen biološki proces koji zavisi od kombinacije unutrašnjih i spoljašnjih faktora. Ovaj rad analizira uticaj ključnih ekoloških faktora - temperature, dostupnosti vode, svetlosti, pH vrednosti i uslova skladištenja na klijavost semena, sa posebnim osvrtom na ratarske useve. Temperatura ima ključnu ulogu u enzimatskoj aktivnosti i metaboličkim procesima, pri čemu i previsoke i preniske temperature negativno utiču na klijanje usled oksidativnog stresa i inhibicije enzima. Dostupnost vode je neophodna za rehidrataciju semena i aktivaciju metabolizma, dok višak vlage može dovesti do anaerobnih uslova koji ometaju klijanje. Svetlost utiče na klijavost putem fotoreceptora koji regulišu hormonalnu ravnotežu, utičući na dormanciju i početak rasta. pH vrednost zemljišta utiče na dostupnost hranljivih materija i aktivnost enzima, pri čemu ekstremne pH vrednosti mogu inhibirati metabolizam semena. Na kraju, uslovi skladištenja određuju dugoročnu vitalnost semena, pri čemu visoka vlažnost i temperatura ubrzavaju biohemsku degradaciju. Razumevanje ovih faktora ključno je za optimizaciju klijanja semena i unapređenje poljoprivredne produktivnosti, posebno u uslovima klimatskih promena
Essential Oils and Weed Management – Bioherbicides Potential of Essential Oils
No full textEssential oils are products of specialized plant cells or are produced in the intercellular space and represent a mixture of different compounds such as aldehydes, ketones, alcohols and fatty acids. Due to their chemical composition, essential oils from numerous plants release allelopathic compounds of high phytotoxcicity and can be used in weed control. During the last decades, the interest in using essential oils as a safe alternative to the application of herbicides in crop protection against weeds has been increasing. Essential oil-based herbicides have become a topic of interest for agriculture of the new age due to increasing concerns about the adverse effects caused by conventional pesticides. However, despite well-documented research around the world in which the effectiveness of numerous plant essential oils has been proved, little is currently known about their mechanism of action as herbicides at the molecular level. Furthermore, there are a few commercially used preparations on the world market. This should be the focus of future research and the spectrum of action should be expanded
Садржај фотосинтетских пигмената у органски и конвенционално произведеном семену кукуруза и соје
No full textФотосинтетски пигменти у семену имају важну улогу као индикатори физиолошке зрелости, виталности и потенцијала за клијање, као и одраз услова производње. Циљ овe студије био је да испитају разлике у садржају хлорофила а и б и укупних каротеноида у семену кукуруза (сорта Руменка) и соје (сорта Каћа) из органске и конвенционалне производње. Узорци су прикупљени у периоду од 2015–2017. године са поља Института за кукуруз „Земун Поље“ (кукуруз) и Института за ратарство и повртарство у Новом Саду (соја). Садржај пигмената одређен је применом технике УВ/ВИС спектофотометрије, очитавањем апсорбанци добијених екстраката на 663 nm, 646 nm и 470 nm и изражен у µg/g суве материје. Хлорофил а код кукуруза показао је високе сезонске варијације (0,53–7,39 µg/g), са значајно вишим вредностима код органског кукуруза у 2016. и 2017. години (3,6 пута, односно 6,6 пута) у односу на конвенционални. Хлорофил б није показао разлике 2015–2016. године, док је 2017. године детектован само код конвенционалног кукуруза (5,5 µg/g). Каротеноиди нису измерени у већини узорака. Код соје, хлорофил а је варирао у опсегу од 3,6–23,8 µg/g (2016. године био је већи код органске соје 1,7 пута, а 2017. године код конвенционалне - 6,3 пута). Хлорофил б је варирао од 0,132–42,7 µg/g: 2016. године виши је био у органској (2 пута), а 2017. године у конвенционалној соји (323 пута). Каротеноиди су утврђени само код конвенционалне соје 2016. године. Добијени резултати указују на значајан утицај начина производње и сезонских услова на садржај фотосинтетских пигмената у семену, што може послужити као индикатор квалитета и физиолошког стања семена
The contribution of organic agriculture to preservation and protection of genetic resources
No full textConservation genetics as an interdisciplinary scientific field has become almost
compulsory in biodiversity preservation and in providing sustainable and successful
farming, particularly in terms of global changes in climate and considerable increase in
food demand. In Serbia, with the great potential of agroecology, organic cropping and
breeding is a very useful approach to the preservation and protection of genetic
resources. Organic agriculture, which disallows the application of any chemicals,
including artificial manures and fertilisers, and which promotes natural procedures and
processes, contributes to the preservation of plant and animal landraces that are
commonly adjusted to specific local agroecological conditions. The present paper
focuses on the performed studies related to organic farming, which significantly
contributed to the conservation of genetic resources. This was done through the analyses
of practices including the preservation of landraces (indigenous varieties), alternate
cropping (crop rotation), the application of compost and green manure, and the
prevention of the use of GMO technologies. Thanks to the application of these
techniques, organic agriculture improves the soil fertility, decreases risk of the depletion
of genetic resources, provides better resistance of flora and fauna to changes in climate.
In comparison with the conventional production, putting organic farming into practice
is confronted with many obstacles including higher investments, lower yields, technical
and educational limitations. In order to cope with these problems, agricultural
legislation has to be improved, education of farmers should be supported in order to
motivate them to transfer from conventional to organic farmin
Genetic characterization of maize landraces using SSR markers: Insights for breeding applications.
No full textThis study aimed to evaluate the genetic diversity of traditional maize landraces and identify
promising germplasm for breeding by performing molecular characterization of 31 maize
landraces and 5 testers using Simple Sequence Repeat (SSR) markers. Of the 33 SSR primers
initially tested, four were excluded due to monomorphism or low amplification efficiency,
while the remaining 29 revealed a total of 139 alleles, with an average of 4.8 alleles per locus.
The highest number of alleles (7) was observed with primers phi087 and phi080, whereas four
primers (umc1265, umc1282, phi075, and umc1310) each detected the lowest number (3).
Genetic distance analysis based on the Nei method revealed a high level of variability. Among
the landraces, genetic distances ranged from 0.11 (AN2249 vs. AN2047) to 1.97 (AN1509 vs.
AN1267). Population AN1509 exhibited the highest average genetic distance (1.643),
suggesting strong divergence potential, while AN1945 had the lowest (0.478), indicating
greater genetic similarity. For the five testers (L217, L73B013, L255/75-5, F2, and Polj17),
genetic distances ranged from 0.43 between L217 and L73B013 to 1.54 between L217 and
L255/75-5. Intermediate values were observed for F2 vs. L255/75-5 (0.64), Polj17 vs.
L255/75-5 (0.57), and Polj17 vs. F2 (0.74), reflecting their differing genetic backgrounds and
pedigrees. These results align with the known pedigree and origin of the testers. Principal
Coordinate Analysis (PCoA) explained 35.9% of the total variation across the first two axes
and revealed clear differentiation between the testers and most local populations. Population
structure analysis (K=4) grouped the genotypes into four distinct clusters. The testers formed
a homogeneous group, while the local populations exhibited greater intra-population
diversity. These findings highlight the broad genetic base of the maize landraces and identify
highly divergent genotypes. Among them, AN1509, with its pronounced genetic divergence,
stands out as a valuable resource for future breeding programs
The Effects of Pre-Fermentative Treatments on the Aroma of Krstač and Žižak Wines
No full textPre-fermentative treatments are essential in winemaking, as they significantly influence the quality and stability of white wines in particular. The synthesis of many compounds obtained from yeast, such as higher alcohols and esters, is influenced by the type and concentration of aromatic precursors present in the must, especially amino acids. Clarification has a positive effect on wine quality, mainly by improving organoleptic properties, with flavour being the most affected. In this study, the influences of different static settling times, different pressures during must extraction and the addition of different bentonite concentrations to the must on the aroma of wines from the autochthonous grape varieties Krstač and Žižak were investigated. The identification of aromatic compounds in the wine was performed using GC/FID-MS analysis. Wine subjected to the longest static settling time (30 h) showed the highest concentration of esters. Krstač wine, which underwent a 30 h of settling, was characterised by an increased concentration of esters, such as isoamyl acetate, ethyl decanoate and ethyl hexanoate, while Žižak wine was characterised by the presence of 2-phenylethyl acetate and isoamyl acetate. The total fatty acid content in Krstač wine obtained by pressing was higher (14.90 mg/L) than in wine produced from free-run juice (8.04 mg/L)
Dietary exposure and health risks of acrylamide in Serbian market foods: Bread, biscuits, snacks, and potato chips
No full textThis study investigated acrylamide (AA) levels in various bread types, bread parts (crust/ crumb), toast bread at various toasting durations, and non-bread products (biscuits, snacks, potato chips) on the Serbian market, integrating local dietary habits with health risk assessments. AA quantification was performed using hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS), with 95.0 % average recovery and 3.7 % precision. While 91 % of bread samples complied with Serbian regulatory benchmarks, health risk assessment revealed concerns. Analysis showed consistently higher AA levels in bread crust, especially in wholegrain bread with seeds. The analysis of toast bread demonstrated a direct correlation between toasting duration and AA formation. Carcinogenic margin of exposure (MOEc) for even untoasted bread was below 10,000, decreasing with toasting time. Among non-bread products, potato chips contained the highest AA concentrations (295.00–670.00 µg/kg). Mutagenic risk values (Rm) exceeded 1.00E-6 for all samples, with potato chips and toast bread (>5 minutes) showing Rm values above 1.00E-4. According to MOEc only specific bread varieties, three biscuit, and two snack samples demonstrated satisfactory safety levels (MOEc > 10,000). These findings provide valuable insights for food manufacturers and public health authorities in Serbia for developing effective AA mitigation strategies
Bacterial Antimicrobial Resistance in Meat Products—Current Concepts
No full textThis paper presents the main trends in antimicrobial resistance (AMR), as well as their health and other consequences; current knowledge about the emergence, spread, and mechanisms of AMR; and the progress to date in understanding possible pathways of resistance through the food chain and the role of food as a vector of antibiotic-resistant bacteria. We have reviewed the main approaches to the prevention and control of the development, selection, and spread of AMR in food-producing animals (FPAs) and the meat industry; bacterial AMR in FPA; the most significant and dangerous pathogens that show AMR; transmitted by meat and meat products; strategies to prevent the occurrence of AMR microorganism infections; and, recently, AMR monitoring and surveillance programs in meat production and processing. This study reviews the results of various studies, as well as inspiring and motivating reviews, that address the state of the art of AMR in targeted diverse niches that are integrated by the multidisciplinary “One Health” approach, as well as future strategies for reducing AMR. To successfully address the challenges associated with AMR, it is necessary to integrate monitoring and surveillance across the environment–raw materials–food (meat)–people continuum. It is necessary to permanently improve and expand the NCBI Pathogen Detection Isolate Browser (NPDIB) database and supplement it with the results of future research to identify and investigate genes that coordinate stress response and AMR
Molecular “Yin-Yang” Machinery of Synthesis of the Second and Third Fullerene C60 Derivatives
No full textTo overcome the negative effects of the biochemical application of nano-substances in medicine (toxicity problem), using the example of fullerene C60’s first derivative (fullerenol, FD-C60), we show that their biophysical effect is possible through non-covalent hydrogen bonds when around FD-C60 water layers are formed. SD-C60 (Zeta potential is −43.29 mV) is much more stable than fullerol (Zeta potential is −25.85 mV), so agglomeration/fragmentation of the fullerol structure, due to instability, can cause toxic effects. When fullerol in solution was exposed to an oscillatory magnetic field with Re (real) part [250/−92 mT, H(ωt) = Acos(ωt)], water layers around FD-C60 (fullerenol) are formed according to the Penrose process of 3D tiling formation, and the second derivative, SD-C60 (or 3HFWC), is self-organized. However, when Im (imaginary) part [250/−92 mT, H(ωt) = Bisin (ωt)] of the external magnetic field is applied in addition to SD-C60, ordered water chains and bubbling of water (“micelle”) are formed as a third derivative (TD-C60). Fullerol (FD-C60) interacts with biological structures biochemically, while the second (SD-C60) and third (TD-C60) derivatives act biophysically via non-covalent hydrogen bond oscillation. SD-C60 and TD-C60 significantly increased water solubility and reduced toxicity. The paper explains the synthesis of SD-C60 and TD-C60 from FD-C60 (fullerol) as a precursor by the influence of an oscillatory magnetic field (“Yin-Yang” principle) on hydrogen bonds in order to create water layers around fullerol. Examples of biomedical applications (cancer and Alzheimer’s) of this synergetic complex are given. This study shows that the “Yin-Yang” machinery, based on the nanophysics of C60 molecules and non-covalent hydrogen bonds, is possible. The first attempt has been composed to synthesize nanomaterial for biophysical vibrational nanomedicine
The influence of diet on the polyunsaturated fatty acid content in cow‘s milk
No full textDue to the extraordinary importance of polyunsaturated fatty acids (PUFA) for human health (including anti-cancer, anti-diabetic and anti-inflammatory effects), research into increasing the PUFA content in the milk fat of ruminants, especially cows, has gained considerable importance in recent years.
In addition to various genetic and non-genetic factors (such as breed, stage of lactation, pregnancy, seasonal fluctuations), diet has a significant influence on the content and composition of milk fat. The most favourable ratio and the highest PUFA content in milk fat is achieved in animals that graze on pasture or are fed fresh forage on the farm. However, forage production on pasture is unprofitable in lowland regions and this feeding method limits the genetic potential of high-yielding dairy breeds. In many countries, cows are mostly kept on farms and in barns, which requires the use of conserved forage and concentrates throughout the year, regardless of whether the feed is offered separately or as a total mixed ration (TMR).
The nutritional value of the ration can be increased by improving the quality of the roughage (hay, silage, etc.) and/or increasing the proportion of concentrates. Today, silage is almost a standard component of the ration and one of the prerequisites for economically viable milk and meat production in cattle farming. Grass and legume silages have a more favourable effect on milk fat synthesis and the fatty acid profile than corn silage, which lead to trans-10, cis-12 CLA - a very strong inhibitor of milk fat synthesis - during the biohydrogenation of linoleic acid. When certain strains of lactic acid bacteria are used as silage inoculants (e.g. Lactobacillus plantarum AKU 1009a), biohydrogenation of some PUFAs takes place, leading to an increased content of conjugated fatty acids in the silage itself.
An increase in the energy content of the ration can be achieved with starchy feedstuffs or oilseeds. A high starch content in the ration leads to a reduced production of volatile fatty acids (acetic and β-hydroxybutyric acid), which are used for the de novo synthesis of fatty acids (with C atoms <16:0) in the udder. This leads to a decrease in milk fat content and changes the fatty acid profile - the content of saturated fatty acids (SFA) increases and the content of PUFAs and CLA decreases. The use of certain oleaginous feeds significantly increases the PUFA content. Among the varieties tested (soya beans, sunflower, linseed, cottonseed, peanuts), the highest increase in CLA content (by 60%) was achieved with heat-treated soya beans, which also had a higher content of non-degradable proteins