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Maize is important agricultural crop that is susceptible to infections by various phytopathogenic fungi. Maize grain as a rich source of nutrients represents a very good medium for the development of toxic fungi from the different genera. Synthetic fungicides are generally used to protect plants from various pathogenic fungi. However, this practice increases the risk of fungicide resistance and environmental degradation of agroecosystems. The use of Trichoderma isolates in biological control is an alternative strategy, particularly for the problems of resistance and environmental pollution, thus improving the economic and biological sustainability of agroecosystems. In this paper, the effect of medium composition on the production of Trichoderma harzianum biocontrol agent effective against maize pathogens, Helminthosporium carbonum and Penicillium sp., was examined. Results of Scheffe multiple range test showed that the best medium for production of T. harzianum bioagent effective against H. carbonum and Penicillium sp. contains soluble starch as carbon source and soybean meal as nitrogen source. By applying this medium formulation, maximal inhibition zone diameters of 54.33 mm and 24.67 mm was registered in vitro for H. carbonum and Penicillium sp., respectively. Production of Trichoderma bioagent was further tested on the selected medium in a ten times larger volume, Woulff bottle, in which the success of this bioprocess was confirmed. The results obtained in an increased volume on a selected medium showed that this bioprocess can be shortened to 84 h, which contributes to the economy of the bioprocess.

The increasing usage of chemicals for plant protection in recent years has become a serious problem. One of the possible solutions is use of beneficial microorganisms instead of synthetic fungicides, which will contribute to the protection of the environment and human health. Since the fungi Aspergillus flavus and Fusarium graminearum are the most important pathogens that cause maize diseases and produce mycotoxins, the potential of Trichoderma harzianum for biocontrol of both phytopathogens was examined in this paper. The aim of this paper was to study the influence of different carbon and nitrogen combinations in the medium for T. harzianum production. T. harzianum was cultivated in Erlenmeyer flasks and the effect of cultivation broth against selected maize pathogens was tested using well diffusion method. The results of this study showed that the combination of different carbon and nitrogen sources in the T. harzianum cultivation medium statistically significantly affects the production of Trichoderma cultivation broth effective on two tested phytopathogens. Dextrose as a carbon source and soybean flour as a nitrogen source proved to be the best combination in the medium for production of T. harzianum cultivation broth effective on A. flavus and F. graminearum. Maximal inhibition zone diameters of 31 mm and 56.33 mm were registered in those medium formulations for A. flavus and F. graminearum, respectively. These researches represent an important step for further research in which a medium of low market value would be selected. This would reduce the price of the production process but also the final product.

Maize is one of the most important field crops with broad genetic and phenotypic variations. It occupies an important place in agricultural production in the world as in Serbia. The main aim of maize breeding is to obtain new inbred lines, i.e. to identify new hybrid combinations that will surpass existing hybrids in terms of grain yield and other important traits. The aim of this study was to examine the phenotypic variability of 10 NS maize hybrids of different genetic bases and maturity groups in agroecological conditions in Rimski Šančevi, to consider the interdependence of grain yield and other tested traits using PCA and correlation analysis. The obtained results indicate a significant variation of all examined properties except for the ear length. The significance of the difference indicated by the F test was confirmed by the Duncan test. Correlation coefficients indicate a significant positive interdependence between the mass of 1000 grains and the ear length (r = 0.698). PCA analysis provided a more complex analysis of the interdependencies of the examined traits and grain yield. The highest yields were achieved by hybrids that simultaneously showed high values of several yield components. Yields ranged from 11,210 kg ha-1 in the G-10 hybrid (FAO 600), to 14,790 kg ha-1 in the G-3 hybrid (FAO 400). In this study, hybrids of earlier maturity achieved higher grain yields, mainly due to drought tolerance. Therefore, the goal is to create drought-tolerant maize hybrids that will successfully endure the negative consequences of global warming.

The objective was to assess the effect of chemical desiccation on seed germination and storability in three sunflower female inbred lines and to point at possible indicators for optimal performance time. Desiccation was performed with Diquat (2 l ha-1) applied at 7-day intervals from the end of flowering to harvest maturity. There were 6 treatments and control (untreated). Germination was tested 2 and 21 months after harvest. The highest germination was recorded when the desiccation was performed 35 days after flowering. Results showed that optimal moment for applying chemical desiccation when there is no negative effect on the seed germination is specific for each sunflower genotype. Seeds with a high level of germination (>90%) can be stored for 19 months without significant loss in germination, namely, it was not negatively affected by chemical desiccation. Seed moisture and growing degree-days can be used as reliable indicators for optimal desiccation time.

The aim of this study was to investigate whether different priming treatments could affect emergence, speed of emergence and yield of freshly produced and aged maize seeds sown at different depths. Two lots of parental maize line A634 produced in the previous season were used as seed source, and twenty-year-old seed. After priming with distilled water and 0.5% KNO3 solution, the seed was sown at four depths. Results showed that freshly produced seeds did not benefit from priming treatments. Reaction of the aged seeds differed depending on the priming treatment. Results indicated that priming with KNO3 should be avoided in aged seeds of A634 because of its detrimental effect on the emergence and yield. Hydropriming induced higher percentage of emerged plants and faster emergence, but with no effect on yield. Reaction to priming treatments varied with sowing depth, which should not exceed 5.0 cm for parental line A634 according to this study.

This review paper discusses the content of natural ( 40K, 238U, 226Ra, and 232Th) and artificial (137Cs) radionuclides in the soil of the mountains of Maljen, Tara and Kopaonik in the Republic of Serbia over 2002-2015. In addition, the paper gives radiation hazard parameters, i.e., radium equivalent activity, absorbed dose rate, annual effective dose equivalent, external hazard index, annual gonadal dose equivalent, and excess lifetime cancer risk outdoors that we calculated from the obtained content of the natural radionuclides in the soil samples. We compared the parameters to previously published results for different parts of the country and looked into the radioecological status of the investigated areas.

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Introduction/Objective. Chronic obstructive pulmonary disease (COPD) exacerbation is mostly triggered by infectious agents and seriously compromises the patient’s quality of life and predicts a poor outcome of the disease as well. If the signs of the probable bacterial cause of COPD exacerbation are presented in an intubated patient, initial antimicrobial management must be launched. Depending on the results of the respiratory system sample cultures, the initial antimicrobials can be changed or continued. The objective of this study is to present in-hospital suggestions regarding the use of the initial antimicrobial management of urgently intubated COPD adults with the probable bacterial cause of exacerbations, considering the source of bacterial acquisition (i.e. facility- or community-acquired bacteria). Methods. The cross-sectional study covered 51 patients urgently intubated on admission to the medical Intensive Care Unit of the Zemun Clinical Hospital Center during 2015/2016. The patients were divided into two groups: community-acquired (n = 26) and facility-acquired infection group (n = 25). The respiratory system samples were processed in the Microbiology Laboratory. Results. Acinetobacter and Pseudomonas spp. were the most frequently isolated bacteria in both groups, followed by Staphylococcus aureus and Klebsiella spp. as the third most frequent bacteria in the community- and facility-acquired group, respectively. The parallel use of tigecycline and aminoglycosides proved to cover a sensitive microbial spectrum in 52% of examinees of the community-acquired and 32% of examinees of the facility-acquired group. Conclusion. The present study suggests the initial management of intubated adults with probable bacterial infection-induced COPD exacerbation by the parallel use of tigecycline and aminoglycosides. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 173033]

Introduction. The aim of this study was to determine the content of radionuclides and toxic elements in samples feedstuffs and food of animal origin collected between 2007- 2017 from two suburban areas of Belgrade, the municipalities of Palilula and Surčin, both areas with intensive agricultural production. Materials and Methods. Radionuclides (40K and 137Cs) and toxic elements (As, Cd, Cu, Ni, Pb and Zn) were determined in samples of corn, hay, meat, milk and eggs, by gamma ray spectrometry and inductively coupled plasma spectrometry (ICP-OES, Spectro Genesis). Results and Conclusions. The obtained results showed that natural 40K was present in all investigated samples. The average activity concentration of 40K was 94 Bq/kg in corn, 117 Bq/kg, 108 Bq/kg and 95 Bq/kg in beef, pork and chicken meat, respectively, as well as 61 Bq/kg in cow’s milk and 48 Bq/kg in eggs. Anthropogenic radionuclide 137Cs was not detected. The trend for toxic element levels according to the average concentrations found in the studied feed samples (corn and hay) was as follows: Zn>Cu>Pb>As>Ni>Cd. Arsenic was detected in animal feed in both Belgrade municipalities, with the average concentration being 1.08 mg/kg (0.5-1.37 mg/kg), and in corn, the As content was higher than in hay samples. In food of animal origin, only Zn and Cu were detected. It is concluded that the presence of radionuclides and toxic elements in feedstuffs and foods of animal origin does not pose a health risk for either humans or animals. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31003 and Grant no. 173018]

The content of radionuclides (40K, 238U, 226Ra, 232Th, and 137Cs) and heavy metals (As, Cd, Cu, and Pb) was determined in samples of soil, vegetables and medicinal plants collected in the period 2007-2017, from two suburban areas of Belgrade – the municipalities of Palilula and Surčin, and Pančevo – the 'Dr Josif Pančić' Institute for the Study of Medicinal Herbs. During the research period, activity concentration of 137Cs in soil decreased from 16 Bqkg–1 to 3.9 Bqkg–1 (Palilula, Belgrade) and from 18 Bqkg–1 to 12 Bqkg–1 (Surčin, Belgrade). Mean activity concentrations of natural radionuclides in the soil were higher than the global aver- age. Trend for heavy metal levels, according to the average concentrations found in the soil, were as follows: Cu >Pb >As >Cd for Palilula, Pb >Cu >As >Cd for Surčin and Dr Josif Pančić' Institute, Pančevo. The obtained results indicate that the industrial pollution has no impact on food production in the study area and that the main anthropogenic source of radionuclides and heavy metals in soil are mineral phosphorous fertilizers, often used in agricultural fields. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31003 and Grant no. 173018]

Kopaonik is the highest mountain in Serbia with excellent conditions for breeding large and small ruminants. It has many natural and cultural opulences and it's one of largest tourist center in Serbia. The aim of our research was to analyse specific concentration of 137Cs and 40K in environment of Kopaonik mountain, and to compare results with those mesured one year after the chernobyl accident on a same locations. Samples of soil, mosses, hay and milk were collected on a diferent altitude from six locations in townships Raška and Brus. Results have show that radioactive 137Cs is still present in environment of Kopaonik in samples of soil and mosses. The highest specific concentration of 137Cs in a soil has been mesured in Jošanička banja (142 Bq/kg), and in a mosses in Lisina (228 Bq/kg). In most samples of soil specific concentration of 137Cs was half lower compared with obtained values from 1987. and it matches its physical half-life period of 30 years. In the samples of hay and milk specific concentration of 137Cs was below detection limit, and it indicate that this radionuclide is not included in the food chain. [ABSTRACT FROM AUTHOR]

Introduction. Bilateral abdominoscrotal hydrocele is a rare entity in childhood. The etiology of abdominoscrotal hydrocele has not been fully clarified. The diagnosis is based on clinical examination, ultrasound and magnetic resonance imaging. The treatment is surgery. Case outline. This paper presents an eight-month-old boy who was admitted at the department of pediatric surgery due to bilateral swellings in the scrotum area. The changes were first noticed when he was three months old and the diagnosis of bilateral abdominoscrotal hydrocele was confirmed after the scrotum ultrasound examination. When the patient was six and eight months old, the symptoms have significantly increased, the magnetic resonance of the abdomen and the lesser pelvis was performed, and the bilateral abdominoscrotal hydrocele was successfully treated with inguinal surgery. The operative and postoperative course was uneventful. Conclusion. In this paper, we presented a rare form of hydrocele in children, as well as diagnostic evaluation that involved ultrasound and magnetic resonance examination. Surgical treatment by inguinal approach is also presented.

The aim of this study was to investigate field emergence parameters, number of plants that reached reproductive stage and yield of seed lots with different count of abnormal seedlings. In standard germination test these seedlings are discarded from the count of germinated seed, presuming that they will not develop into normal plants. Five lots of hybrid NS 640 with different percentage of abnormal seedlings were tested. Results showed that in favourable environment conditions, large number of abnormal seedlings emerged, reached reproductive stage and participated in yield formation. However, emergence of seed lots with high percentage of abnormal seedlings was longer than for lots with small number of abnormal seedlings. Laboratory germination and germination energy were more correlated with indicators of field emergence rate, while total percentage of germinated seedlings (normal and abnormal) was more correlated with grain yield. However, it can be expected that in adverse environment conditions, abnormal seedlings are less likely to develop into normal plants.

Instrumental neutron activation analysis is used to determine a content of 47 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Cd, Sb, I, Ba, Cs, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Tm, Yb, Lu, Hf, Ta, W, Au, Hg, Th, and U) in mosses (Homolothecium sp., Hypnum cupressiforme Hedw., and Brachythecium mildeanum (Schimp.) Schimp.) and lichen (Cladonia fimbriata (L.) Fr.) collected in three locations in Eastern Serbia over years 2006-2010. Concentrations of six elements (Zr, Nd, Gd, Tm, Yb, and Lu) in mosses in Serbia are measured for the first time. For other elements, the obtained concentrations fall within the ranges reported for mosses and lichens in Europe, but no declining trend in concentrations of V, Cd, Cr, Zn, Ni, Fe, and Cu, that has been described in the literature, can be inferred from our results. Factor analysis shows that terrigenous and industrial components are the highest contributing factors to the elemental composition and that the most polluted measurement site is in the vicinity of a copper mining and smelting complex. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III43007: Climate changes and their influence on the environment: impacts, adaptation and mitigation and Grant no. III43009: New Technologies in the Environmental Protection]

Plodia interpunctella (Hübner), the Indian meal moth (IMM), is a major lepidopteran storage pest worldwide. IMM larvae can be found in high abundance in stored maize and cause huge losses in seed germination and seed viability. This work aimed to assess the susceptibility of six maize hybrids (NS 6140, NS 640, NS 1090, NS 444 - dent type, NS 620k - pop-corn type, Red-aleurone maize - maize with an altered aleuron color) to IMM attack and suitability for pest's development. Standard laboratory diet (SLD) was used as a positive control. Under laboratory conditions, the following IMM life history parameters were monitored: larval mortality, mean developmental duration (egg to adult), adult emergence, adult lifespan and female fecundity. Kernel susceptibility was determined based on the Susceptibility Index (SI). The highest mortality of IMM larvae was on NS 620k (35.25%) compared to the other maize hybrids (11.2-19.5%). The highest number of emerged adults was on Red-aleurone maize (17.5), and the lowest on NS 620k (4.0). The longest lifespan was recorded for moths reared on NS 6140 and NS 640 (8.5 and 8.7 days, respectively). The highest female fecundity was on SLD (115.8 eggs), on Red-aleurone maize (44.3 eggs), while females reared on NS 620k laid the lowest number of eggs (22.8 eggs). Moths reared on NS 620k had the shortest body sizes (0.9 cm), which indicated reduced moths fitness. SI showed that Redaleurone maize (SI=7.79) was the most susceptible to IMM attack, while NS 620k (SI=3.08) was the least susceptible.

The objectives of this study were to determine the effects of different priming treatments and genotypes on maize germination and early seedling growth traits, as well as to examine the associations among these traits. In addition, the application of genotype by trait biplot methodology in this type of analysis was evaluated. Seed priming treatment was conducted on ten maize inbred lines by soaking seeds in water (hydropriming) or in 0.5% KNO3 solution. Seed was sown in sterile moistened sand and placed at suboptimal (15°C) and optimal temperature (25°C) for seven days. After that, seedling length and seedling weight were measured, final germination, time to 50% emergence and vigour index were calculated. The results showed that seed priming can improve seedling growth traits at both temperatures. There are differences in genotype responses to various seed priming solutions. The observed differences represent useful information for the selection of adapted maize inbred line and adjustment of priming treatment for sowing in different temperature conditions. This study showed that biplot could easily be used for assessing the effect of seed priming, or some other treatment, on seedling growth traits. Moreover, it can be used to understand the associations among the seedling growth traits.