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This paper presents the results of an analysis of influence of the “light” steaming process on conventional drying and colour of beech timber. A stack consisting of steamed and unsteamed boards was dried. Moisture content and moisture content profiles were recorded, and at the end of drying final moisture content, moisture content difference across thickness, case-hardening and colour were determinated. No statistically significant difference between steamed and unsteamed timber was established in any of the examined parameters (MC, ΔMC, gap). The results indicate that equal (or even) better drying quality can be expected with steamed beech timber than with unsteamed timber, given the same drying schedule. Dry steamed timber was darker and more reddish than the unsteamed one. An imprecision of measurement by probes in the kiln was noticed in measuring steamed and unsteamed beech timber having a moisture content of between 7% and 15%, and a solution for overcoming this problem was given. [Projekat Ministarstva nauke Republike Srbije, br. TR 31041]

The goal of this word was to examine the parameters of color of beech wood before and after thermal treatment, and to determine if there is a difference in color between sapwood and red heartwood before and after application of high temperature. Samples were treated at temperatures of 170°C, 190°C and 210°C, respectively, during 4 hours. Color coordinates (CIEL*a*b* system) were measured before and after treatment by using the following parameters: ΔL, Δa, Δb and ΔE - color change. Color was assessed at four spots on the radial and cross-section surfaces of wood and their mean values were taken for further calculations. Acquired results show that the applied heat treatment of sapwood did not significantly influence the change of color difference between cross-section and radial surfaces. The difference between cross-section and radial surfaces, in nontreated red heartwood was smaller than that measured in sapwood. The color difference of nontreated sapwood and red heartwood was more pronounced on the radial than on the cross-section surface. Application of high temperature caused a significant decrease of this difference. Temperature of 210°C caused the smallest color difference between these two parts of wood which was in this research determined on the radial surface. It was concluded that the applied thermal treatment almost equalized the colors of sapwood and red heartwood, especially on the radial surface, and from this aspect it can be concluded that these two parts of beech wood were completely equalized. It should also be noted that in the case of equalized properties, sapwood and red heartwood can be equally applied in a final product made of thermally treated beech wood. [Projekat Ministarstva nauke Republike Srbije, br. TR 37008 i br. TR 31041]

Growing demand for better quality and cheaper products put on the need to industry to balance between the two kinds of needs, which are the reduction of production costs and to ensure a high quality product. This is the case with dried sugar beet pulp as a byproduct of sugar refining process. One of the possibilities to reduce energy consumption is savings in the process of thermal dehydration in the process of the conventional drying of pulp. Pulp drying is one third of total energy consumption in the sugar factory. Acidification of water extraction result in pulp that could be pressed better and in other hand in the juice with less non-sucrose compounds. Keeping the extraction process under certain conditions, directly affects on the quality of the extracted pulp and on effects of their further processing. This paper examines the impact of the extraction parameters of sugar from sugar beet and agents of acidification for water extraction (sulphurous acid, hydrogen peroxide) on the quality of dried sugar beet pulp. Extraction of sugar from sugar beet cossettes by hydrogen peroxide at pH 5.5 to 8.5 does not cause changes in mechanical properties of sugar beet cossettes and in water retention coefficient, but increases the brightness of dried sugar beet pulp for about 5-7 units, which solubility in water does not depend on the applied concentration of extracting agents, but increases in dependence on the duration of the extraction. Sugar beet pulp extracted at pH 11.0 has reduced strength, they are highly hydrated, and under the force they lose their shape, binding a larger amount of water thus reducing the effect of their pressing. The changes in microstructure were probably accompanied by segmenting the linear parts of macromolecules and are reflected in the increase of water retention capacity and increase the solubility of dried sugar beet pulp for two to three times. Under the same conditions of extraction, sulphurous acid produces similar but relatively mild changes in the characteristics of extracted and dried sugar beet pulp compared to conditions when hydrogen peroxide is used. From the point of the quality of the product of extraction, the most favorable results are obtained when the extraction is carried on at pH 5.5 for a period of 1 h at 70 °C, using water for extraction with sulphourus acid with the addition of 5% hydrogen peroxide. Under these conditions no significant degradation of sugar beet tissue is detected, do not change the physical, chemical and mechanical properties of the extracted pulp. But there is an average increase of lightness of dried noodles for about 7 units, which represents a significant improvement of their quality, since there is difficult to sell on the market the dried sugar beet pulp with increased colour.

This paper presents the results of an analysis of the existing seed sources managed by SE ?Srbijasume?. A proposal has been given for new seed sources to be designated in forest areas. This paper highlights the significance of seed sources as a form of in situ conservation, as well as the necessity of establishing seed orchards as a form of ex situ conservation of forest genetic resources, which improves the mass production of reproductive material of forest trees characterized by good genetic quality.

The data on forests shown in this paper which are general useful functions determine the main way of managing, because these forests are marked as water protective and especially significant for the water supply of the Vrnjacka Banja area from 1985. These are forests of beech and beech mixed with fir of the highest quality located in the river Zagrza basin on mountain Goc and they represent more than 85 % of the basin and provide the hydrological and water protective functions at the highest level. For that reason, they have a special protective status. In the river Zagrza basin, there is the management unit "Seliste" of particular importance and the accumulation Seliste was built there with about 380 000 m3 volume and its primary task is water supply of the Vrnjacka Banja area during critical months without water. The aim of this scientific paper is to emphasize the need of increasing and protecting the water potential using adequate ways of forest vegetation management, which means overall basin organization. The final result should be related to the optimal use of natural sources in that area.

Carvacrol is an active ingredient of essential oils from different plants, mainly from oregano and thyme species. It poseses biocidal activity agains many artropodes of the importance for veterinary and human medicine. Carvacrol acts as repelent, larvicide, insecticide and acaricide. It acts against pest artropodes such as those that serve as mechanical or biological vectors for many causal agents of viral, bacterial and parasitic diseases for animals and humans. Therefore, it may be used not only in pest arthropodes control but in vector borne diseases control, too. In the paper carvacrol bioactivity against mosquitoes, house flies, cockroaches, ticks and mites are described. Potencial modes of carvacrol action on artropodes are given, too. Carvacrol reachs its biotoxicity against arthropodes alone or in combination with other active ingredients from the same plant of its origin, such as tymol, cymen or others. The paper explains reasons for frequently investigations on essential oils and other natural products of plant origin to their biotoxicity against food stored pest or pest of medicinal importance, as well as, needs for their use in agriculture, veterinary and human medicine. Karvakrol je aktivni sastojak esencijalnih ulja različitih biljnih vrsta, a uglavnom vranilove trave i timijana. Ima biocidno dejstvo u odnosu na mnoge artropode od značaja za veterinarsku i humanu medicinu. Karvakrol deluje kao repelent, larvicid, insekticid i akaricid. Ispoljava toksičnost u odnosu na štetne artropode koje predstavljaju mehaničke ili biološke vektore za mnoge uzročnike virusnih, bakterijskih ili parazitskih bolesti životinja i ljudi. Zato je moguće da se koristi, ne samo u kontroli štetnih artropoda već i u kontroli bolesti koje prenose insekti i akarine. U radu je opisana biološka aktivnost karvakrola u odnosu na komarce, kućne muve, bubašvabe, krpelje i grinje. Takođe su opisani i verovatni načini delovanja karvakrola na insekte i akarine. Karvakrol ostvaruje svoje insekticidno i akaricidno delovanje ili sam ili u kombinaciji sa drugim sastojcima esencijalnog ulja u kojem se i sam nalazi, kao što su na primer timol, cimen i drugi sastojci. U radu su objašnjeni i osnovni razlozi učestalih istraživanja esencijalnih ulja i drugih prirodnih proizvoda biljnog porekla na biotoksičnost u odnosu na štetočine uskladiš tene hrane, štetočine od zdravstvenog značaja kao i potrebe za njihovu primenu u poljoprivredi, veterinarskoj i humanoj medicini.

The paper deals with environmental enrichment for domestic animals at farms, animals in zoos, experimental animals and pet animals. Also, the paper defines and describes different strategies of environmental enrichment. Environmental enrichment is a simple and effective mean of prevention of boredom, behavioral disorders as well as an effective mean of improving animal welfare in farm, zoo, companion and experimental animals. Different items and materials may be used for environmental enrichment. They need to be evaluated for use by taking into account the following: the species of an animal, its needs, habits and capabilities, the type of an enrichment device, the device's ability to stimulate the animal's interest and the safety of the device. Enrichment programmes should always include two forms of enrichment: behavioral enrichment and environmental enrichment. Enrichment comes in many forms such as structural or physical enrichment, sensory enrichment (auditory and olfactory stimulation), dietary enrichment, manipulatable enrichment and social enrichment. U radu je iznet značaj obogaćivanja uslova života za domaće životinje na farmama, životinje u zoološkim vrtovima, kućne ljubimce i ogledne životinje. Data je definicija obogaćivanja uslova života i opisane su različite strategije ovog zahvata. Obogaćivanje uslova života predstavlja jednostavan i efikasan način sprečavanja dosade i poremećaja ponašanja kao i efikasnu meru poboljšanja dobrobiti životinja. Za obogaćivanje uslova života mogu se koristiti različiti predmeti i materijali. Njihova upotreba zahteva poznavanje bioloških karakteristika vrste životinja kod kojih se primenjuje obogaćivanje uslova života, poznavanje njihovih potreba, staništa i sposobnosti, vrste predmeta i materijala koji će se koristiti u programu obogaćivanja uslova života, svrsishodnost primene određenih predmeta i materijala u procesu obogaćivanja sa aspekta sposobnosti da motivišu, odnosno stimulišu životinje na ispoljavanje prirodnih oblika ponašanja i stepen njihove pouzdanosti i sigurnosti, odnosno potencijalni rizik primene određenih predmeta i materijala za životinje. Programi modifikacije uslova života obično obuhvataju dva oblika obogaćivanja, a to su strukturno i bihevioralno obogaćivanje. Obogaćivanje uslova života poseduje mnoge oblike kao što su fizičko, senzorno (auditorno i olfaktorno), hranidbeno, manipulativno i socijalno obogaćivanje uslova života.

Seaweeds are an excellent source of compounds with biological activity. Particularly interesting are the sponges, which suited in medicine reaches into the distant past. The biological effects of extracts and new compounds from sponges have been reported in numbers of scientific papers. Sponges produce a plethora of chemical compounds with widely varying carbon skeletons, which have been found to interfere with pathogenesis at many different points. Due to this, sponges have the potential to provide future drugs against important diseases, such as cancer. All of this makes them particularly interesting to examine the antitumor activity. In this paper for the first time presented a data of investigations of antitumor activity of extract of sponge Acanthella acuta, in vitro. Crude samples of Acanthella acuta (phylum Porifera) were collected from the natural locality in Adriatic Sea, the Bay of Kotor, and subjected to extraction. After that, we examined the cytotoxicity and cell cycle distribution of dichloromethane/methanol (1:1) extract of Acanthella acuta, on two human malignant cell lines, human cervix carcinoma (HeLa)and human colon carcinoma (LS174): and also a normal fetal lung fibroblast cell line (MRC5). The IC50 values in the MTT assay in LS174 and HeLa cells were ranged from 9.92±0.54 to 29.51±μg/ml. Moreover, cytotoxic activity of Acanthella acuta extract on normal MRC5 cells was not observed. Cell cycle distribution was quantified by flow cytometry. In vitro antitumor activites was accompained by an important subG1 accumulation of HeLa cells after treatment of tested cell lines with extract.

By the development and analysis of the model of beech roundwood production and consumption trends in the most important European countries, Serbia and Europe altogether, for the period 1990-2000, the paper identifies the regularities in their trend, based on which the relations in the production and consumption trends are analyzed. Based on the elements obtained in this way, the paper points to the possibilities of selling beech wood offered by the European market.

The paper presents the floristic diversity of the left bank of the Danube and the canal network of Krnjaca and Borca settlements, as well as the factors that endanger it. 216 autochthonous and allochthonous plant species were recorded in the investigated area. A large number of invasive plant species have been observed that spread rapidly and easily forming stable populations that displace native plants. Some of them are: Amorpha fruticosa L., Robinia pseudoacacia L., Ailanthus altissima (Mill.) Swingle, Asclepias syriaca L., Ambrosia artemisiifolia L. and others. The presence of 6 species that are rare and endangered in Serbia is especially significant, as well as 5 relict species. During the investigation, the factors which influence on natural habitats degradation and the reduction of autochthonous floristic diversity were identified. Accordingly, measures for protection and preservation of autochthonous floristic diversity are recommended.

A new motpellier maple (Acer monspessulanum L.) site was described in this paper, located on mountain Boranja, in forest management unit ?Istocna Boranja?, above Roguljski potok, on Glogovita kosa ridge. Montpellier maple occurs on elevations between 460 and 480 m a.s.l., on southwestern and western aspect, on very steep slopes with inclination 45? t? 50?. The site area is 874 m2, ?nd coordinates of site centre are: ?=19?13?49.0? and ?=44?25?21.33?. In this site, Montpellier maple occurs in a plant community of hop-hornbeam and manna ash, and considering that Montpellier maple was recorded in all three layers, and that it occurs abundantly in shrub and ground layers, a subassotiation with montpellier maple was set apart (?stryo carpinifoliae-Fraxinetum orni subass. ?ceretosum monspessulanii). According to floristic composition, most plant species belong to the submediterranean floral type, so this community represents an enclave of submediterranean vegetation in the belt of continental beech forests. The community is of azonal character, orographically-edaphically conditioned, and occurs in warmer aspects, on shallow and skeletal rendzina on oolithic limestones.

Douglas-fir is one of the most common conifer species in the forest plantations of Europe. The provenance test model is based on the analysis of the properties (growth, anatomical, physiological, chemical, mechanical and other properties) of Douglas-fir in order to justify the transfer of seeds from North America to the ecosystems of Serbia. This type of program has been implemented in Serbia on several locations using different Douglas-fir provenances. Given that the analysis of different physiological properties of trees is important for the introduction of specified provenances into habitats in Serbia, in this paper the variability of potassium concentration in young Douglas-fir needles of different provenances was examined in an experimental field in Serbia. Potassium is very important in the physiological processes of plants. It is an essential element involved in a number of biochemical and physiological processes and plays a significant role in the adaptation of plants on biotic and abiotic stress factors. The highest potassium concentration was found in the “Oregon 205-14” provenance - the only provenance in which the potassium concentration was significantly higher than the average value, so it can be characterized as a superior provenance for the uptake and accumulation of this element. It was found that, at this stage of development, the differences in the potassium concentration in trees in the provenance test have no significant effect on growth parameters. Further studies should show whether the concentration of this biogenic element in any way affects other properties important for the selection of provenances during the introduction process, such as resistance to stress factors. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 31070: The development of technological processes in forestry in order to realize the optimal forest cover and Grant no. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation]

This paper presents the structure of well-preserved, mature stands of seed origin and young stands that followed either after planned regeneration or spontaneously in the understory reinitiation stage, in monodominant sessile oak forests (Quercetum petraeae Čer. et Jov. 1953.) from two subassociations, tilietosum and typicum, in the territory of „Đerdap” National Park. The presentation of mature stands is based on the data collected from experimental plots in 1992, in the period characterized by the mass occurrence of sessile oak decline in this area, and across Europe. The stands were around 150 years old in 1992, and consisted only of sessile oak in the tree layer. The canopy closure of the stands was 0.7-0.8, with a large standing volume. There were no major differences between the stands regarding social classes, stem quality, crown development and crown condition. The presentation of young stands is based on the data collected in 2017 from a permanent experimental plot, as well as on the data from other authors. The structure of young stands indicates that different silvicultural measures need to be planned during the regeneration stage for different subassociations of the monodominant sessile oak forest in order to reach sufficient natural regeneration of sessile oak. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31041, Grant no. III43007 and Grant no. III43010]

Weeds are constant companions of plant production. For their control chemical substances, ie herbicides are used. In addition to a number of properties, the use of herbicides has numerous consequences, for the living world and for the environment, as well. Considering their negative effects, there is a need to find alternative methods of weed control. In recent decades, numerous researches have been done within the framework of biologically and eco-friendlier acceptable ways of controlling various pests, including weeds. Bioherbicides are compounds that contain microorganisms (such as bacteria or fungi), products of their metabolism, or plant extracts that have an effect on certain weed species. In this paper, the application of plant extracts that show allelopathic effects, as potential bioherbicides, in modern agricultural production, will be discussed.

Inadequate choice and application of control measures for agricultural pests, ectoparasites of livestock and domestic animals, vectors and reservoirs of various diseases of human medicine and veterinary importance in urban areas has caused the resistance occurrence and cross-resistance in a large number of arthropods. Their control is becoming increasingly difficult and challenging. For example, the use of acaricides is indispensable in the control of European red mite (Panonychus ulmi, Acari: Tetranychide), but also for other species from this family that are all significant pests in agricultural production, horticulture and forestry. The resistance occurrence and maintenance and cross-resistance in arthropods is a global phenomenon. The aim of this paper was to present the resistance factors and mechanisms in Panonychus ulmi control and to list the active substances for which there was an evidence that resistance has been acquired, all with the goal of pointing out the problem of resistance in this species and highlight the ways to prevent it. The occurrence and evolution of resistant arthropod populations could have multiple consequences that can be observed from an agricultural, economic, health, and environmental perspective.

Seed health testing aims to ensure a healthy crop and to prevent the spread of plant diseases. The need to study and apply both essential oils and plant extracts against seed diseases is growing and becoming more important. Coriander (Coriandrum sativum L.) is an annual herbaceous, aromatic, spicy and medicinal plant from the Apiaceae family, known for its seeds with a characteristic and pleasant odour. In human medicine, coriander is a part of various medicines for the treatment of digestive organs. Phytopathogenic fungi and bacteria are the most common and significant causes of coriander seed disease. The aim of this study was to assess coriander seed health and investigate the possibility of seed disinfection using peppermint (Mentha x piperita) essential oil. The health of the seeds was examined by the filter paper laboratory standard method. Different concentrations (1, 2, 5 and 10%) of peppermint essential oil were used for seed disinfection. The composition of the essential oil was determined by gas chromatographic analysis. The results of seed health analysis showed the presence of a fungus after seven days of incubation in a humid chamber at room temperature. The fungus was identified as Alternaria sp. (sect. Alternaria) based on the symptoms and macroscopic and microscopic features of the fungus (on seed and potato dextrose agar). Immersion treatment of infected seed in peppermint essential oil reduced the presence of Alternaria sp. on coriander seeds. The highest disease inhibition, 69,33%, namely 58,93% without the influence of the emulsifier, was shown by oil solution of 5%. Stagnation in inhibition was observed with a further increase in oil concentration. The results of this study show the possibility of disinfecting coriander seeds with peppermint essential oil to reduce infection with Alternaria sp.

The production of beans and green beans in our country takes place in relatively small areas, and it is additionally reduced by the presence of various harmful agents (pests and diseases). Economically significant diseases of beans and green beans are gray rot (Botrytis cinerea), white rot (Sclerotinia sclerotiorum), seedling rot, and seedling blight (Pythium sp.), Fusarium wilt (Fusarium oxysporumf. sp. phaseoli), bean rust (Uromyces phaseoli), anthracnose (Colletotrichum lindemuthianum), gray leaf spot (Mycosphaerella pinodes), brown leaf spot or bacterial blight (Xanthomonas campestris pv. phaseoli), and bean mosaic virus. Five plant protection products (PPPs) based on four active substances have been registered in our country for the control of pathogens in beans and green beans. Signifi cant pests of beans and green beans in our country are black aphid (Aphis fabae), thrips (Kakothrips robustus), plant aphids (family Aphididae), cotton bollworm (Helicoverpa armigera), as well as red spider mite and Atlantic (strawberry) spider mite (Tetranichus urticae and Tetranichus turkestani). Eight PPPs, based on seven active substances, have been registered for the control of pests in the crop of beans and green beans. This paper aimed to present the registered PPPs in the Republic of Serbia for the control of the most economically important pathogens and pests of beans and green beans, classified according to the mode of action.

The paper presents the seed production technologies of maize sown on three different sowing dates. Seeds of three maize inbred lines (L1, L2, L3) were used as a seed material in the location of Zemun Polje in 2018. The objectives of the present study was to determine the importance of different sowing dates as a method to overcome stressful conditions caused by unfavourable environmental factors, as well as to point out to a significance of the seed size in sowing. Effects of the following factors were observed in relation to emergence and the maize grain yield: sowing date (SD), seed fraction (LF, SF and PF) and genotype (L). The gained results indicate that the lowest percentage of emergence was determined in the variant L2/SD2/SF (34%), while the highest grain yield was determined in the variant L3/SD1/ PF 8.86 t/ha. The standard deviation of the yield is the largest for variants with the highest yield U radu je prikazana tehnologija semenske proizvodnje kukuruza sa tri različita datuma setve. Kao semenski materijal koriščeno je seme tri smooplodne linije L1, L2, L3 na lokaciji Zemun Polje u 2018 godini. Cilj rada je bio utvrđivanje značaja primene različitih datuma setve kao način prevazilaženja stresnih uslova nastalih nepovoljnim ekološkim činiocima, kao i ukazati na značaj krupnoće semena u setvi. Efekti faktora :datum setve (SD), frakcija(LF, SF, PF) i genotip(L) posmatrani su u odnosu na broj k lijalih semena posle setve i prinos zrna kukuruza. Rezultati ukazuju da je najniži procenat niklih semena bio u primenjenoj varijanti L2/SD2/SF (34%) i najveći prinos za varijantu L3/SD1/PF 8.86 t/ha. Standardna devijacija prinosa najveća je za varijante sa najvećim prinosom dok je varijansa nicanja semena obrnoto proporcijonalna. Efekti faktora na nicanje u proizvodnim uslovima i prinos zrna kukuruza su različitog značaja. Rok setve kao tehnološka mera u proizvodnji semenskog kukuruza ali i u merkantiln oj proizvodnji zrna vrlo je značajna za procenat niklih semena, kao i njegova interakciji sa frakcijom i genotipom. Ukupan doprinos faktora u varijansi nicanja semena je preko 50% R=0,678. Na varijansu prinosa efekat je slabijeg intenziteta i iznosi R=0,490. Razlike dobijene primenom različitih varijanti u proizvodnji semenskog materija ukazuju na značaj delovanja faktora i njihovo dalje istraživanje.

Variability of introduced tree species can be assessed through provenance tests. Their genetic and ecological adaptability can be confirmed by investigating the variability of anatomical traits, analyzed in this research study. The aim of the paper was to determine whether there are differences in the width of transfusion parenchyma of Douglas-fir needles in different provenance in different habitats in Serbia. In Serbia, 2 provenance tests of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), whose seed originated from North America, were established with the aim of testing the species. A 2-factor analysis of variance of the thickness of needle transfusion parenchyma was carried out in order to study the effects of the interactions between site-specific conditions of the locations where the provenance tests were set. The role of this parenchyma is to support conductivity of water and mineral matters from xylem bundles and organic matters from chlorenchyma to phloem bundles. The analysis of variance shows that there are statistically significant differences in the values obtained for the studied anatomical traits between the provenances. LSD test shows that the provenances are homogeneous, i.e. there are no statistically significant differences in the mean values between them. The smaller range of variation in the properties of these provenances in comparison to other provenances can be partially explained with their genetic similarity which led to similar phenotypic expressions in the interaction with the external factors of the experimental sites. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31070: The development of technological processes in forestry in order to realize the optimal forest cover” and Grant no. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation]

This paper presents the possibilities of using medicinal plants in the territory of the ?Kursumlija? Forest Administration. The research was carried out within the ?Sagonjevska Crna Cuka? Management Unit, with an area of 2578,67 ha, where 20 sample plots were established (5 in each compartment). These sample plot circles were arranged into a network through compartments 42, 43, 44 and 46 at a distance of 100 m, in the north-south, east-west directions. The radius of each circle is 1.80 m, with an area of 10 m?. The environmental conditions were determined in each of the marked sample plots. The medicinal plants were identified and their number was determined, while the cover and association of medicinal plants were also calculated. After that, samples of different medicinal plants were taken for measurement, both fresh and dry, to determine the potential of the biomass of medicinal herbs in the investigated area. The research results showed that the total estimated amount of medicinal herbs biomass in the investigated area was 186.67 kg per hectare. The estimated amount of dried medicinal plants has a significant potential and should be thoroughly examined and used in the future.

INTRODUCTION: Peptic ulcer is a group of upper gastrointestinal ulcer diseases in which the aggressive effect of hydrochloric acid and pepsin on the mucous membrane of this system plays the most significant role. The two most common causes of peptic ulcer are Helicobacter pylori eradication and overuse of non-steroidal anti-inflammatory drugs. In this paper is presented the patient with duodenal ulcer treated at the University Hospital Foca in the Department of Gastroenterology. VIEW OF THE PATIENT: Patient aware, oriented, acting exhausted, shortness of breath, moderately nourished, afebrile, acyanotic, pronounced general weakness and languor, gait instability and dizziness. Pulse 100/min,TA 160/100mmhg. The troubles began with a feeling of nausea, and three days before admission he threw up dark contents. After that he had a dark excrement on a couple of occasions. The problems became more and more acute, and after the laboratory analyzes he was sent to the University Hospital in Foca. States that he has been drinking a lot of pain medication for 4-5 months because of the severity of his spine pain(isialgia). Receives hypertension medications. The patient's mother had stomach problems, denied allergies, and food or medication. The patient gave us information that he is a non-smoker and occasionally he consumed alcohol. Chronic cough and thick cough expectoration are present, lasting for a long period. After a thorough history, a physical examination of the findings of the esophagogastroduodenoscopy, the gastroenterologist made the diagnosis - Ulcer of the duodenum. CONCLUSION: After the completion of hospitalization, the patient's physical and mental condition improved significantly. The patient expressed satisfaction with the quality of health services, information received, health care and hospital treatment.

This paper presents the results of testing the compression of Serbian spruce wood from plantations and natural stands. Compression perpendicular to grain in radial and tangential direction was tested. A dilatation of 1% was taken for a conditional boundary dilatation, and the appropriate strength for the conditional limit strength was taken. Six trees from plantations and nine trees from natural stands were analyzed. In total, 309 samples were tested. The regression analysis examined the dependence of these mechanical properties on the width of the annual rings, the percentage of late wood and wood density.

This paper shows the results of the analysis of the fruit morphometric characteristics of 29 trees of sycamore maple (Acer pseudoplatanus L.) and red - leaf sycamore maple (Acer pseudoplatanus ??tropurpureum? Sp?th.) in Novi Sad area. Based on the test trees, it can be concluded that the analyzed secondary population of sycamore maple has a high level of intra - populations variability, based on different degrees of variability of measured parameters and statistically significant differences of all analyzed parameters within the analysed genotypes. The results indicate that there are certain differences between fruit of sycamore maple and its red - leaf variety. Given that there is no statistically significant difference between sites and different urban spaces, it can be concluded that stress factors caused by a high degree of urbanity do not affect the morphometric characteristics of fruits in the analyzed test trees. Testing the symmetry of fruits indicates a high level of genetic variability within the analyzed population.

In order to cope with all the natural phenomena and survive on different types of soil and in different climatic conditions, plants have perfected their means of propagation. Weed seeds are characterized by high diversity in all segments, both physical and chemical. Knowledge of the morphological characteristics of seeds and fruits of weed plants (mass, size, shape, colour, luster, odor, appearance of surface structures) is of great importance in the planning of weed control measures. The subject of this study were the seeds of the species Chenopodium album, C. hybridum, Anagallis arvensis, Veronica hederifolia and Amaranthus retroflexus, which were isolated during the weed seed bank assessment in the soil. After the physical extraction from the soil samples, the seeds were separated from the admixture, determined and then photographed with a stereomicroscope. The dimensions (length, width, seed thickness and length of the navel) were measured and any changes in the seed coat produced as a result of physical damage were monitored. The aim of this research was to expand the database, which should contribute to a more efficient determination of weed seeds. It was found that the seeds of the species studied in this paper were often broken and damaged, although in most cases with similar morphological features, as indicated by the literature data. The seeds of the species C. album were an exception, with dimensions significantly different from the data available in the literature. This occurrence can be explained by the diversity of seed anatomy in the Chenopodiaceae family and also by the fact that during their stay in the soil, permanent changes in the seed surface structures are possible. Da bi se izborili sa svim pojavama prirode i opstali na različitim tipovima zemljišta i različitim klimatskim uslovima biljke su usavršile svoje načine širenja. Seme korova se odlikuje velikom raznolikošću u svim segmentima, kako fizičkim tako i hemijskim. Poznavanje morfoloških osobina semena i plodova korovskih biljaka (masa, veličina, oblik, boja, sjaj, miris, izgled površinskih struktura) ima veliki značaj u planiranju mera za suzbijanje korova. Predmet istraživanja ovog rada bila su semena vrsta Chenopodium album, C. hybridum, Anagallis arvensis, Veronica hederifolia i Amaranthus retroflexus izdvojena tokom procene rezerve semena korovskih biljaka u zemljištu. Nakon fizičke ekstrakcije iz zemljišnih uzoraka semena su odvojena od primesa, urađena je determinacija semena a zatim su semena slikana stereomikroskopom. Izmerene su dimenzije (dužina, širina, debljina semena i dužina pupka) a praćene su i eventualne promene na semenjači koje su nastale kao posledica fizičkih oštećenja. Cilj ovog istraživanja je proširivanje baze podataka koja bi trebalo da doprinese efikasnijoj determinaciji semena korovskih vrsta. Ustanovljeno je da su semena vrsta koja su bila predmet proučavanja u ovom radu često bila polomljena i oštećena, mada u većini slučajeva sličnih morfoloških osobina kao što ukazuju podaci iz literature. Izuzetak su bila semena vrste C. album, čije su se dimenzije značajno razlikovale od podatka dostupnih u literature. Ova činjenica se može objasniti raznolikošću anatomske građe semena vrsta iz familije Chenopodiaceae ali i saznanjem da je tokom boravka semena u zemljištu moguća trajna promena površinske strukture.

The paper examines the influence of three clonal rootstocks ('Pixy', 'Fereley' and 'St. Julien A') along with seedlings of Myrobalan (control) on the growth, yield and fruit quality of the plum cultivar 'Čačanska Rana'. Research was conducted in the area of the Belgrade Danube basin for the six-year period (2013-2018). In comparison to control, all three clonal rootstocks have shown a significant effect on the decrease of vigor expressed as a trunk cross-sectional area. The lowest vigor was found in trees on the 'Pixy' rootstock, then on 'Fereley' and 'St. Julien A' rootstocks. Regarding the rootstocks 'Fereley' and 'St. Julien A', significantly higher fruit set and yields were achieved in comparison to control. Clonal rootstocks induced an increase in the yield per hectare ranging from 72% to 93% compared to Myrobalan. The highest yield efficiency was found in the trees on the 'Fereley' rootstock, followed by the yields observed in the trees on the 'Pixy' and 'St. Julien A' rootstocks. Significantly higher fruit weight compared to control was obtained in the trees on the 'Fereley' rootstock. Rootstocks did not show any significant effect on the soluble solids and total acid contents of the fruit. Based on the results obtained, it can be concluded that all three clonal rootstocks showed better results than Myrobalan, and can be recommended for establishing intensive plum plantations with higher planting density. The best results in terms of yield and fruit quality were obtained with the 'Fereley' rootstock. U radu je ispitivan uticaj tri vegetativne podloge (Pixy, Fereley i St. Julien A) i sejanaca džanarike (kontrola) na rast, rodnost i kvalitet ploda sorte šljive Čačanska rana. Istraživanje je obavljeno na području beogradskog Podunavlja u periodu od šest godina (2013-2018). U odnosu na kontrolu, sve tri vegetativne podloge su ispoljile značajan uticaj na smanjenje bujnosti izražene preko površine poprečnog preseka debla. Najmanja bujnost je bila kod stabala na podlozi Pixy, zatim Fereley i St. Julien a. Na podlogama Fereley i St. Julien a dobijeno je značajno veće zametanje plodova, kao i prinos po stablu u odnosu na kontrolu. Na vegetativnim podlogama prinos po hektaru bio je veći za 72% do 93% u odnosu na džanariku. Najveći koeficijent rodnosti imala su stabla na podlozi Fereley, a za njom slede Pixy i St. Julien a. Značajno veća masa ploda u odnosu na kontrolu dobijena je kod stabala na podlozi Fereley. Podloge nisu ispoljile značajan uticaj na sadržaj rastvorljive suve materije i ukupnih kiselina u plodu. Na osnovu dobijenih rezultata, može se zaključiti da su sve tri vegetativne podloge dale bolje rezultate u odnosu na džanariku i mogu se preporučiti za podizanje intenzivnih zasada šljive sa većom gustinom sadnje. Najbolji rezultati u pogledu rodnosti i kvaliteta ploda dobijeni su kod podloge Fereley.

The paper presents the testing results during seed processing of natural seed of red clover and alfalfa, with different initial purity. Because of their exceptional importance in the production of animal feed in the Republic of Serbia, a large number of perennial leguminous plants are grown. The most important leguminous fodders in Serbia are alfalfa and red clover. This is because of the areas they occupy, as well as the nutritional quality for domestic animals. The seed used for the crop establishment of these plants must be clean, with high germination and genetic value. Many of these requirements could be accomplished by seed processing and removing all impurities and seeds of poorer quality. The aim of this study was to show the parameters of efficiency of processing machines of these two perennial legumes seed. The basic indicators of the parameters of efficiency of seed processing are the quality and quantity of the obtained seed. All relevant parameters which define the characteristics of seed processing machines are presented: pure seed (%), weed and other seed crops (%), inert matter (%), amount of processed seed (kg), seed losses (%) and processing output (%). The obtained results enable the selection of suitable equipment and their proper adjustment for seed processing, depending on the quantity and type of weeds and other ingredients presented in the natural seed.

The paper shows results of analysis of influences of oscillating parameters of drying on measuring wood moisture content in the kiln, rate and quality of drying. For this analysis, we used a conventional drying cycle, a cycle with oscillating equilibrium moisture content (EMC), and a cycle with oscillating temperatures. A special software tool was created for managing the oscillations. It was shown that oscillations of EMC and temperatures result in cyclic changes in wood MC, but also in the additional inaccuracies of MC measurements in the kiln. The drying process of the cycle with oscillating EMC lasted somewhat shorter than the other two cycles. Drying quality was the same or better in the cycles with oscillations as compared to the conventionally dried cycle, and the smaller tensions in the wood confirmed the activation of the additional mechano-sorptive effect during cyclic changes of MC in surface layers. [Projekat Ministarstva nauke Republike Srbije, br. TR 31041 i br. TR 37008]

The paper presents the results of an analysis of morphometric characteristics of Norway spruce seedlings in the progeny tests in Bosnia and Herzegovina, localities: Drinic and Srebrenica. Progeny tests were established by using seedlings originating from six natural populations from Bosnia and Herzegovina. Seedling height, root collar and whorl distance from the ground, which represents seedling heights in 2011, 2012 and 2013 were measured. The results indicate statistically significant differences between the analyzed characteristics of the observed population. Especially interesting are the populations Potoci and Olovo, which showed the highest growth during the observed period in both progeny tests. The impact of the drought in 2013 can be seen in the progeny test in Srebrenica where height growth in 2013 was lower by more than 50% in comparison to 2012. The impact of drought in the progeny test in Drinic was not observed. The research provides the baseline when selecting the starting population, where the rapid growth of seedlings is set as the main goal.

Mastitis in dairy cows is an economically important disease because it makes up 38% of all diseases that occur in intensive cattle breeding. Mastitis affects milk production, either temporarily or permanently, depending on the course of infection and type of pathogen agent. Regular and timely therapy of mastitis based on the application antimicrobials, apart from prophylaxis, is very important for good health of breeding stock. This paper presents the case of repeated mastitis in a cow, Holstein-Friesian breed, 5 years old, which did not respond to antibiotic therapy. Milk samples from each separate quarter of the udder were collected under aseptic conditions and sent to the laboratory for further bacteriological tests, for isolation and identification of pathogens, as well as to test pathogen resistance to some antibiotics. On the basis of bacteriological examinations, there was confirmed the presence of Streptococcus dysgalactiae, which showed sensitivity to ampicillin, cloxacillin and augmentin, intermediate resistance to tetracycline and resis­tance to kotrimeksazol.(cotrimoxazole-proveriti). Mastitis goveda predstavlja oboljenje koje izaziva najveće ekonomske gubitke kod mlečnih krava i čini 38% od svih oboljenja koja se javljaju u intezivnom uzgoju mlečnih krava. Mastitisi utiču na proizvodnju mleka, privremeno ili stalno u zavisnosti od toka infekcije i vrste uzročnika. Pravilna i pravovremena terapija supkliničkih mastitisa, zasnovana je na primeni antimikrobnih lekova i pored profilakse je ključna za dobro zdravstveno stanje zapata. U ovom radu je prikazan slučaj hroničnog mastitisa krave holštajn frizijske rase, starosti 5 godina, koja nije reagovala na antibiotsku terapiju. Uzorci mleka su uzeti u aseptičnim uslovima, iz svake četvrti pojedinačno, i poslati u laboratoriju radi izolacije i identifikacije uzročnika i ispitivanja osetljivosti uzročnika na antibiotike. Na osnovu detaljnih bakterioloških ispitivanja potvrđeno je prisustvo Streptococcus dysgalactiae (Strep. dysgalactiae) koji je pokazivao osetljivost na ampicilin, kloksacilin i augmentin, intermedijarnu osetljivost na tetraciklin, i rezistenciju na kotrimoksazol.

High intensity of infection with ascaridida Parascaris equorum can lead to intraluminal obstruction of the ileum in foals, especially during the first dehelmintisation (during and after weaning), more rarely in older ones. Bowel obstruction is followed by strong colic pain and shock, which inevitably leads to death, especially in cases when an adequate therapy is not taken on time. The paper describes four cases of small intestine obstruction with ascarididae in foals of American trotter race, provoked by an antiparasitic agent. The first symptoms appeared about twenty hours after the treatment with antiparasitic. Two of the foals have been cured with medicament therapy, one died, and in one case there was taken surgery in field conditions. Visok intenzitet infekcije askarididom Parascaris equorum može da dovede do intraluminalne opstrukcije ileuma kod ždrebadi, naročito tokom prve dehelmintizacije (u vreme i nakon odbijanja), ređe kod starijih jedinki. Opstrukciju creva prate jaki količni bolovi i šok, koji neminovno dovodi do uginuća, naročito u slučajevima kada adekvatna terapija nije preduzeta na vreme. U radu su opisana četiri slučaja opstrukcije tankog creva askarididama kod ždrebadi rase američki kasač, koja je bila isprovocirana antiparazitikom. Prvi simptomi su se pojavili dvadesetak sati od tretmana antiparazitikom. Dva ždrebeta su izlečena uz medikamentoznu terapiju, jedno je uginulo, pri čemu je u jednom slučaju preduzeta hirurška intervencija u terenskim uslovima.

This paper presents the results of research of efficacy of the lightweight low power chainsaw Stihl MS 260 in the operations of juvenile thinning in preserved even-aged mixed stands of pedunculate oak with hornbeam, ash and other hard hardwoods. The investigations were carried out in the territory of FE “Sremska Mitrovica” in three sample plots of different ages. It is the first research of this kind based on the choice of optimal technological solution for the cleaning cuts of oak stands. Technology of work is based on cutting unwanted species at a certain height in order to favor pedunculate oak as the main species. In sample plot 1 the cutting through of undesirable species was carried out in one place and then third parties carried out their processing and transportation. In sample plots 2 and 3 workers cut the unwanted species in several places and stacked the timber on the ground so as not to interfere with the growth of pedunculate oak which does not tolerate shading. In this study, we applied time and work study. Group system of work was recorded. The group typically consisted of 4 workers and a foreman. Fuel consumption was recorded by the method of tank refuelling. The research results show that operating conditions have a significant impact on the effects of work with a chainsaw, as well as on the consumption of fuel and lubricants. The differences are mainly caused by different structures of cut timber.

Drug discovery based on development of selective ligands for a specific target intended to modulate its activity and revert pathophysiological process is now recognized as too simplistic to design effective agent for complex multifactorial diseases, characterized by diverse physiological dysfunctions caused by deregulations of complex networks of proteins. Major challenge in modern drug discovery is to rationally design multitarget drugs able to specifically modulate only a group of desired targets while minimizing interactions with off-targets. Multifactorial cerebral mechanisms implicated in mental (psychiatrics) and neurodegenerative diseases and interactions of the neurotransmitter systems are two main reasons for applying polypharmacology ('multi-target') strategy in drug discovery for these complex brain diseases. In this paper we review polypharmacological profile and potential therapeutic application of dopamine D1-like receptor antagonists. Istraživanje novih lekova koji deluju kao selektivni ligandi za određeno ciljno mesto i tako usporavaju ili zaustavljaju patofiziološki process danas se smatra nedovoljno efikasnim u razvoju lekova za kompleksna oboljenja nastala usled više patofizioloških procesa i promena u nekoliko signalnih puteva. Najveći izazov predstavlja razvoj lekova koji specifično modifikuju aktivnost nekoliko izabranih ciljnih mesta dejstva, a istovremeno minimalno stupaju u interakciju sa ostalim biomolekulima. Kompleksni patofiziološki procesi psihijatrijskih i neurodegenerativnih oboljenja i interakcija neurotransmiterskih sistema su dva ključna razloga za primenu strategije polifarmakologije (strategije multiplih ciljnih mesta) u razvoju efikasnih lekova koji deluju na centralni nervni sistem. U ovom radu dat je pregled polifarmakoloških profila i potencijalne terapijske primene antagonista receptora koji pripadaju D1 familiji dopaminskih receptora.

The paper presents the results of four seed lots produced in Serbia and Belarus in two years, and examines the influence of their quality on 1000 seed mass, germination energy and total germination. There was no impact of the region or the year on the studied seed quality parameters. There was high variability of 1000 seed mass (CV = 20.3 %) taken from different seed lots of Italian ryegrass. Lower variability was found for germination energy and total germination (CV = 9.88 % and CV = 7.98 %). Ryegrass seed lots had lower variability for 1000 seed mass (CV = 8.34 %), germination energy and total germination (CV = 4.80 % and CV = 3.70 %). In the seeds of both species there was no significant correlation dependence of seed mass regarding germination energy and total germination. Significant influence was determined in both species between germination energy and total germination (P≤0.001 and P≤0.05). Italijanski i engleski ljulj su značajne krmne i/ili ukrasne trave. U proizvodnji stočne hrane uglavnom se koriste u smeši sa leguminozama. Seme ovih vrsta se u Srbiji koristi delom iz proizvodnje u Srbiji, delom iz proizvodnje izvan Srbije (iz uvoza). Belorusija I Ukrajina se značajni proizvođači semena trava. Ma gde se proizvodnja semena odvijala kvalitet semena je od presudnog značaja za uspešno zasnivanje travnjaka i/ili travno-leguminoznih useva. U radu su prikazani rezultati ispitivanja po četiri partije semena proizvedenog u Srbiji I Belorusiji tokom dve godine I uticaj regiona proizvodnje na masu 1000 semena, energiju klijanja I klijavost. Nije utvrđen jasan zaključak o uticaju regiona proizvodnje (Srbija i Belorusija) I godine u kojoj se odvijala proizvodnja (2014 i2015) na ispitivane parameter kvaliteta. Između partija semena italijanskog ljulja je utvrđena visoka varijabilnost za masu 1000 semena (CV=20.3%), dok je za energiju klijanja I ukupnu klijavost utvrđena niža varijabilnost (CV=9.88% I CV=7.98%). Između partija semena engleskog ljulja je utvrđena niža varijabilnost za masu 1000 semena (CV=8.34%), kao I za energiju klijanja I ukupnu klijavost (CV=4.80% I CV=3.70%). Na semenima obe ispitivane vrste nije postojala značajna korelativna zavisnost mase semena sa energijom klijanja I ukupnom klijavošću. Takođe na obe vrste je utvrđena značajan (P≤0.001 i P≤0.05) pozitivna korelacija između energije klijanja i ukupne klijavosti.

The aim of this paper was to provide an overview of the recent research concerning truffle biology, ecology and cultivation in Serbia and worldwide. Truffles are ectomycorrhizal fungi, primarily from to the genus Tuber (Ascomycota: Pezizales) which form underground fruiting bodies. Unless they form a symbiotic relationship with plant roots, truffles do not produce fruiting bodies. Survival and reproductive success of truffles is affected by numerous ecological factors (climate, soil characteristics and vegetation). They emit aromatic volatile organic compounds to attract free living organisms such as insects and mice that serve as vectors for truffle dispersal. Truffles use volatile signaling molecules throughout their life cycle to regulate interactions with microorganisms and plant roots. The most cultivated species of truffles in the world is the species T. melanosporum, followed by T. aestuvum. Inoculation with spores is the most common method for production of plants colonized with truffle mycorrhizas. It is recommended to plant seedlings with a high degree of truffle colonization in order to increase the production of fruiting bodies in plantation. Truffle plantations should be established using local genetic resources. In order to preserve natural truffle populations in Europe, the focus should be shifted from searching for truffles in nature to the establishment of plantations with mycorrhized seedlings.

This paper presents an overview of the results achieved in the laboratory for molecular studies of the Institute of Lowland Forestry and Environment, University of Novi Sad, in the field of biotechnology, mainly in molecular genetics, genomics and functional genomics. Researches are designed to serve as a breeding tool. The aim was to clarify the processes of classical genetics by applying modern methods and enable a qualitative and rapid progress in understanding the processes that occur at the level of genes in the genome of forest plant species and thus help the processes of conservation of valuable taxa at the time of global climate change. The results are presented within various research fields and by type of forest trees that were given priority by importance in forest ecosystems. Studies have in most cases been of applicative character with the aim of solving the major problems in forestry, but also of fundamental nature when they were necessary to elucidate the response of forest species to the induced stress, which is an inevitable component of the time characterized by tolerance and adaptation as keywords. [Projekat Ministarstva nauke Republike SRbije, br. III 43002: Biosenzing tehnologije i globalni sistem za kontinuirano istraživanje i integrisano upravljanje ekosistemima i br. III 43007: Istraživanje klimatskih promena i njihovog uticaja na životnu sredinu - pracenje uticaja, adaptacija i ublažavanje i IPA - OXIT]

In this paper are presented the analyzes of some morphometric properties, leaves area stomata density and the intensity of leaves transpiration of white poplar, Populus alba L. and canadian poplar, Populus x canadensis Moench ‘I 214’ in populations at (1) flooded (wet) and (2) unflooded (dry) habitats on the Ada Ciganlija river island during the growing season. Six trees of each species from both habitats were selected, with similar height, age and physiological condition. The morphometric analysis of the analysed poplar species show that the type of habitat did not influence tree height and trunk as well as the leaves area. However, crown width and trunk diameter were greater in the wetter habitat. It was found that the intensity of transpiration of Populus x canadensis ‘I 214’ trees had higher average values (0,73 gH2Odmˉ²hˉ¹) than white poplar (0,68 gH2Odm ˉ²hˉ¹). Transpiration of both taxa was more intensive on the drier than on the flooded habitats. By analyzing the number and size of stomata on leaves of the investigated Populus x canadensis ‘I 214’ trees, it was found that stomata are more numerous but of smaller size on the leaves from drier habitats. It could be concluded that both species could have impact on microclimate conditions by increasing air moisture content and decreasing air temperature but Canadian comparing to white poplar, slightly greater. Increasing air temperature is a consequence of evident global climate change. Through transpiration plants reduce summer air temperature indirectly, by increasing its relative humidity. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation]

Today, in vitro culture is of the great importance in both scientific investigation of under-researched plant species and plant production. In this paper, a review of development and methods of in vitro culture is presented. The main principles are given and the most commonly used methods are described. Special attention was paid to the propagation of Dianthus spp. Tissue culture of commercially important taxa is described in detail, and the review of propagation of other decorative Dianthus spp. that can be used as ornamental plants is also given. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanje klimatskih promena na životnu sredinu - pracenje uticaja, adaptacija i ublažavanje]

This paper presents morphological indicators of the quality of one-year-old seedlings of wild cherry (Prunus avium L.) with special reference to their correlations. The examined parameters were: length, diameter, weight of the aboveground and underground parts, number of buds, root volume, root length and leaf area. The ratio of heights was determined on the basis of the parameters derived: diameter, and the ratio of aboveground and underground parts of a seedling and the Quality Index. Height and diameter have proven to be good indicators of quality. Root volume has proven to be a better indicator of the quality of seedlings than root length. The weight ratio of the aboveground and underground parts of broadleaved trees in the dry state must be defined in advance, both when the measurements are carried out with and without leaves. The Quality Index has proven to be the most comprehensive morphological indicator of quality.

This paper presents the results of an analysis of the morphometric characteristics of the leaves of 14 test black poplar (Populus nigra L.) trees, from the region of Great War Island, indicating a satisfactory degree of intrapopulation genetic variability. The knowledge of the extent and nature of variability in natural populations is a starting point for the breeding and conservation of genetic resources of forest trees. To this end, it is necessary to begin with the implementation of appropriate measures of in situ and ex situ conservation that will enable long-term preservation and enhancement of the ecological adaptability and the evolutionary potential of the populations of black poplar on Great War Island.

Bovine herpesvirus 1 (BHV-1) is one of the most siginificant causes of infections of the respiratory tract of cattle and immunoprophylaxis has a key role in curbing this infection. The intensity of the immune response against BHV-1 following immunization using inactivated commercial vaccines varies depending on the type of vaccine, but it is generally believed that they provide good protection from the development of the clinical form of the infection, and that they are safe. The paper present the development of the humoral immune response in fattening calves that were immunized against bovine herpesvirus 1 (BHV-1) at different time intervals between the primary and the secondary immunization. Calves were administered a commercial vaccine, and then they were divided into two groups which were revaccinated on days 14 or 21. Over a course of the 120 days of the duration of the experiment, blood and nasal mucus were sampled 11 times. The blood serum samples were examined for antibodies to BHV-1 using the virus neutralization (VN) test, and the nasal mucus samples were analyzed using the VN test and the ELISA method. Following revaccination, it was established that there was an increase in the antibody titer in blood of all experimental animals, and it was maintained at a high level up until the very end of the experiment (day 120). In the blood serums, maximum mean values for the antibody titer were determined on day 30 in the group that was revaccinated on day 14, and on day 45 in the group of calves revaccinated on day 21. In nasal mucus, antibodies were established at the earliest, using the virus neutralization test, on day 14 following vaccination, and using the ELISA method only after revaccination. The highest antibody titer in nasal mucus was established on day 45 in the group revaccinated on day 21, and on day 120 in the group revaccinated on day 14. Based on the established antibody titer values, calves can be revaccinated using the inactivated BHV-1 vaccine already on day 14. [Projekat Ministarstva nauke Republike Srbije, br. 31084]

Propagation by cuttings is one of the most successful methods of vegetative propagation of floral crops. In addition to applications in interior decoration, ficuses belong to the group of plants that will potentially be used in green spaces of Belgrade due to global climate changes. In this paper, the possibility of rooting stimulated by adding different concentrations of the indolbytric acid phytohormone was investigated in the commonly cultivated species Ficus benjamina L. and Ficus elastica Roxb.. This is the most commonly used phytohormone in the propagation of ornamental plants due to its stability and stimulation of the rooting process, i.e. its favourable impact on the formation of adventitious roots, their size, number and weight. In this research, the rooting percent of cuttings was 100 % in F. benjamina and 77.66 % in F. elastica. It was found that the highest dose (2 %) of the phytohormone significantly increased all indicators of rooting success in F. benjamina and that the application of weaker concentrations also showed good success. The rooting of F. elastica cuttings was not successful without phytohormones, and the best results were achieved at the phytohormone concentration of 2 %, which increased the dry weight of the roots of this ficus about 4 times. It would be useful to examine higher concentrations of this phytohormone and also some combinations with other rooting stimulators, to be able to make sound recommendations on the optimal dose for the mass production of these ficuses. [Projekat Ministarstva nauke Republike Srbije, br. 43007]

Biofilm formation is one of the main characteristic of Pseudomonas aeruginosa strains. This ability provide bacteria to survive in different, usually restrictivesss environmental conditions. In the same time, biofilm forming is a risk in a many field of industry, mainly in food industry. It is known that diverse P. aeruginosa strains from various environmental sources have different potention to form biofilms. In this paper it is examinated the potention to form biofilm four isolates of P. aeruginosa and based of this results, tested isolates have classificated into four groups. Biofilm formation tested in microtitar plates during the 24 hours at changed conditions of temperature (37°C and 22°C), pH (6 and 7) and concentration of NaCl (1% and 2%). Obtained results have shown that isolated P. aeruginosa have unsimilar ability to form biofilms. Biomass of formed biofilm was greater at 22°C than at 37°C. Also, acid conditions and higher concentration of salt had no inhibitory effect to biofilm forming process. Stvaranje biofilmova predstavlja jednu od glavnih osobina Pseudomonas aeruginosa koja omogućava ovoj bakteriji preživljavanje u različitim, često nepovoljnim uslovima životne sredine. Međutim, formiranje biofilmova predstavlja i faktor rizika u mnogim oblastima industrije, posebno prehrambene, pošto prisustvo čvrstih površina pruža dobre uslove za formiranje biofilma. Kako je poznato da izolati P. aeruginosa koji potiču iz različitih uzoraka poreklom iz životne sredine imaju različit potencijal da formiraju biofilmove, u ovom radu je ispitana sposobnost formiranja biofilmova četiri izolata ove bakterije i izvršena njihova klasifikacija u odnosu na ovu osobinu. Primenjen je statički test u mikrotitar pločama u trajanju od 24 sata u različitim uslovima temperature (37°C i 22°C), pH (6 i 7) i koncentracije NaCl (1 i 2%). Dobijeni rezultati su pokazali da izolati P. aeruginosa imaju različitu sposobnost da formiraju biofilmove, da je masa formiranih biofilmova bila veća na 22°C, kao i da promenjeni uslovi sredine nisu inhibirali stvaranje biofilmova.

The paper analyzes the application of silvicultural measures in young stands in the area of National Park 'Fruška gora', which occurred after the clear-cutting and rep- resent the final stage in the process of regressive succession of zonal communities in the southern peripheral area of the Pannonia (Quercetum cerridis virgilianae B. & Jovanović Vukićević 1977). After clear-cutting the largest share in stands has a lime, coppice origin. Colonization and undisturbed development of invasive neophytes, tree of Heaven (Ailanthus altissima Swingle /Mill./), is a factor of their further degradation. Tree of heaven suppresses a lime from the stand structure, usually the only remaining species from natural communities that has a biological potential to sustain the further development of degraded stands. The aforementioned processes are most intense so far undermines diversity of natural forest communities. The study was conducted in the peripheral area of NP 'Fruška gora' (MU 'Gvozden-jak-lice', division 54, section g) in a stand with different participation of tree of heaven in the structure. In two permanent sample plots were measured the diameter at breast height of all trees and the height of a number of trees for the construction of height curves and calculation of wood volume of represented tree species. On the experimental plot 1 (OP-1), in the upper part of stand (170 m a.s.l.), at the age of 17 years there were seven tree species with a total of 6518 trees ha-1, with basal area of 26.24 m2ha-1 and wood volume of 219.13 m3ha-1. The most represented tree species is white lime, with 65.0% in the number of trees and 83.5% by volume, other types of natural communities are represented with 32.7% in the number of trees and 9.7% by volume, and the tree of heaven is represented with 2.3% in the number of trees and 6.8% by volume. On the experimental plot 2 (OP-2), in the lower part of stand (130 m a.s.l.), at the age of 20 years there were eight tree species with a total of 4045 trees ha-1, with basal area of 34.68 m2ha-1 and wood volume of 338.55 m3ha- 1. The most represented tree species is white lime, with 45.5% in the number of trees and 13.2% by volume, other types of natural communities are represented with 16.5% in the number of trees and 1.2% by volume. Tree of heaven is represented with 35.9% in the number of trees and 80.5% by volume and black locust with 1.9% by trees and 4.9% by wood volume. Mean and dominant diameters and heights of tree of heaven indicate dominance in growth compared to the mean and dominant diameter and height of the lime. To limit the spread of tree of heaven in the stands and, generally, in colonized edges of the NP 'Fruška gora', where the trees of tree of heaven are in the stage of fruiting, as a selection criterion for their removal is proposed the sexual dimorphism. Recorded ratio of male (without seed) and female (with seed) trees of tree of heaven, and negligible presence of mixed flowers on the male trees, provides an opportunity for the implementation of sexual dimorphism as a selection criteria in thinning to stop the spread of tree of heaven by generative way. The crown canopy of lime, and in this context, the crown canopy of grown male tress of tree of heaven, in parts of stands where it dominate, is a factor of self-thinning of tree of heaven in a lower layer of colonized stands.

This paper succesfully investigated the possibility of modification of the micropropagation protocol of Phalaenopsis sp. with an aim to simplify the procedure and reduce the costs. The obtained results show that some medium components can be succesfully omitted (coconut water, glutamine, 2-morpholinoethanesulfonic acid) and some of them (peptone) can be replaced with a cheaper constituent (soy flour) while preserving the quality of the obtained microplants. The multiplication rate was 7,6 shoots per explant after the period of 150 days of cultivation in vitro. On the same medium 60% of explants were rooted and roots were mostly well developed.

There are only ambiguous data in literature that suggest the presence of Galanthus gracilis Celak. in the flora of Serbia. Throughout its range G. gracilis is often confused with closely related species G. elwesii Hook., with which it shares several morphological characteristics, and in some cases the same name is erroneously used for both species (G. graecus Orph.). Only about a decade ago, the genus was a subject of taxonomic revision by the English author Aaron P. Davis, whose work eliminated confusion created by the previous conflicting divisions. Therefore, further studies are required to determine the exact distribution of this species. In this paper, we officially report the presence of G. gracilis in Serbia, with a description of its habitat and estimation of the threatened status.

The research presented in this paper was aimed at better understanding of the relationship between soil properties and the availability of trace elements in pasture soils. The research was conducted in several localities of Stara Planina mountain (Babin zub, Javor I, Javor II and Prelesje), where the dominant soil type is acid humus siliceous soil (Dystric leptosol) characterized by the presence of the Agrostietumvulgaris (capillaris) community Z. Pavl., 1955. In all localities the soil sampling was performed at fixed depths of 0-5, 5-10, 10 -20 and 20 - 40 cm. The pseudo-total contents of trace elements (Pb, Cd, Cu and Zn) (extracted with aqua regia solution), as well as the available contents (extracted with the DTPA chelating agent) in the soil were measured by AAS. The pseudo- total content of trace elements in the soil studied are lower or within the limits for multifunctional land use. A correlation was established between the content of available trace elements in soil and the content of pseudo-total trace elements, as well as between these contents and the properties of the soils studied.

Dimensional change in wood occurs with the change in hygroscopic moisture content, as a consequence of available hydroxyl groups in wood constituents, allowing for the hydrogen bonding with water molecules. Various pretreatments of wood material are being frequently applied in the wood processing industry. One of the main effects of such processes is the hydrolysis of hemicelluloses, which is the main carrier of the free hydroxyl groups in wood material. Hence, the influence of water treatment and the acetic acid treatment on dimensional stability of narrow-leaved ash (Fraxinus angustifolia Vahl. ssp. Pannonica Soo & Simon) were examined in this paper. Duration of treatments was 1h, 2h, 3h and 4h for both solvents. In addition the acetic acid was separately used in concentrations of 3% and 6%. Dimensional stability of the control (referent) and treated sample groups were tested on oven dried samples which were consequently submerged in the distilled water during 32 days. The increase of dimensional stability of narrow-leaved ash was achieved with all of the three treatments (one treatment with water and the two with acetic acid solutions). Simultaneously, it was noticed that the results of water uptake and tangential swelling were not significantly affected by the duration (length) of the treatments. [Projekat Ministarstva nauke Republike Srbije, br. TP-031041]

Respiratormi sindrom goveda (RSG) je multifaktorijalno oboljenje koje nastaje interakcijom infektivnih mikroorganizama, životne sredine i imunološkog odgovora pojedinačnih životinja u stadu. Respiratorni sindrom goveda je predmet istraživanja u poslednjih 50 godina, ali još uvek nije jasna interakcija faktora životne sredine i infektivnih agenasa u patogenezi oboljenja, kao što jos nisu utvrđeni jedinstveni i efikasni programi imunoprofilakse i oblici vakcine koje bi mogle u potpunosti da spreče pojavu oboljenja. U radu su predstavljene osnovne koncepcije postoje}ih programa vakcinacije kod svih proizvodnih kategorija i uzrasta goveda. Takođe, predstavljene su sve oblici vakcina koje se koriste u imunoprofilaksi RSG.Ukazano je na prednosti i nedostatke postoje}ih vakcina kao i na očekivanja od rekombinantnih DNK vakcina. Bovine Respiratory Syndrome (BRS) is a multifactorial disease caused by the interaction of infective agents, the environment and the individual immunological response of animals in the herd. Despite five decades of research on BRS, no clear understanding of how environmental factors influence pathogenic outcomes of the disease has been defined. As such, the development of immunoprophylaxis and vaccine programmes to prevent outbreaks of BRS in cattle has not been successful. The current paper discusses vaccination programmes for all categories of cattle and presents a review of existing vaccines being used for immunoprophylaxis of respiratory syndrome in cattle and discusses the advantages and disadvantages of the currently used vaccines and vaccination programmes. Lastly, a discussion detailing the design of future perfect vaccines is presented.

Cholinergic receptors of parasitic nematodes are one of the most important possible sites of action of antiparasitic drugs. This paper presents some of our own results of electrophysiological and pharamcological examinations of nicotinic and muscarinic receptors of nematodes, as well as data from literature on a new class of anthelmintics that act precisely on cholinergic receptors. The nicotinic acetylcholine receptor (nAChR) is located on somatic muscle cells of nematodes and it is responsible for the coordination of parasite movement. Cholinomimetic anthelmintics act on this receptor, as well as acetylcholine, an endogenic neurotransmitter, but they are not sensitive to enzyme acetylcholineesterase which dissolves acetylcholine. As opposed to the nicotinic receptor of vertebra, whose structure has been examined thoroughly, the stoichiometry of the nicotinic receptor of nematodes is not completely known. However, on the grounds of knowledge acquired so far, a model has been constructed recently of the potential composition of a type of nematodes nicotinic receptor, as the site of action of anthelmintics. Based on earlier investigations, it is supposed that a conventional muscarinic receptor exists in nematodes as well, so that it can also be a new pharamocological target for the development of antinematode drugs. The latest class of synthesized anthelmintics, named aminoacetonitriles (AAD), act via the nicotinic receptor. Monepantel is the first drug from the AAD group as a most significant candidate for registration in veterinary medicine. Even though several groups of cholinomimetic anthelmintics (imiodazothiazoles, tetrahydropyrimidines, organophosphat anthelmintics) have been in use in veterinary practice for many years now, it is evident that cholinergic receptors of nematodes still present an attractive place in the examinations and development of new antinematode drugs. .