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The use of different types of drones in almost all sectors of the global economy is growing rapidly, but the use of drones in agriculture has suddenly increased. According to some data from the literature, the market for different types of drones in agriculture alone is expected to grow from USD 1.2 billion in 2019 to USD 5.5 billion in 2024. A particularly interesting phenomenon is the significant increase in the use of drones (especially various nano-types) in the world and the possibility of some of them being used in agriculture in the Republic of Serbia. The world of drone technology has taken a huge leap forward with the introduction of nano drones. For example, some modern nano drone solutions have dimensions of less than 2 x 2 cm. Nano drones are ultra-small remote-controlled aircraft that can perform a variety of tasks. They are equipped with advanced sensors and functions such as obstacle avoidance and high-speed maneuverability. Some models are even capable of taking aerial photographs, staying in the air for long periods of time and flying autonomously. Nano drones are now more affordable than ever before. Prices range from a few hundred dollars to several thousand, depending on the model and features. Nowadays, nano drones are affordable for everyday users in various fields. This paper introduces nano drone technology (e.g. the type of nano drones and equipment) as a new application for greenhouses: There are some stages that greenhouse growers can consider for the use of nano drones; Safe inspection of the structural components of greenhouses; Pollination processes (e.g. the role of RobotBee); Application of shading composite glasshouses; Crop monitoring/inventory of greenhouses., Upotreba različitih tipova dronova u skoro svim sektorima svetske privrede brzo raste, ali upotreba dronova u poljoprivredi je naglo povećana. Prema nekim podacima iz literature, očekuje se porast tržište različitih poljoprivrednih dronova sa 1,2 milijarde dolara ($USD) u 2019. na 5,5 milijardi dolara ($USD) 2024. godine. Posebno je interesantan fenomen značajno povećanje upotrebe različitih tipova i modela nano dronova u Svetu i mogućnost njihove upotrebe u poljoprivredi (objekti zaštićenog prostora). Svet tehnologije dronova napravio je ogroman korak napred uvođenjem tenologije nano dronova, gde neka moderna rešenja imaju dimenzije manje od 2x2 cm. Nano dronovi su ultra-male letelice sa daljinskim upravljanjem, koje su sposobne da obavljaju mnogo različitih zadataka. Opremljeni su ultra naprednim senzorima sa karakteristikama kao što su izbegavanje prepreka i manevrisanja pri velikim brzinama. Cene se kreću od nekoliko stotina do više hiljada US dolara u zavisnosti od modela, karakteristika opreme i specifičnosti namene. Ovaj rad predstavlja pregled tehnologije primene nekih tipova nano dronova i njihove neophodne opreme i nove primene u staklenicima ili plastenicima (ili slični zatvoreni objekti) kao neke faze koje korisnici staklenika mogu razmotriti za upotrebu, kao što je: Bezbedna inspekcija nekih strukturnih komponenti staklenika/plastenika; Procesi oprašivanja (npr. uloga RobotBee); Primena smeše za osenčenje stakla na svim stranicama staklenika; Monitoring stanja useva/inventar plastenika ili staklenika.

Pšenica je jedna od najvažnijih ratarskih kultura na svetu koja se koristi u ishrani ljudi. U zavisnosti od nivoa zakorovljenosti, korovske biljke mogu dovesti do značajnih gubitaka prinosa, koji prema nekim procenama na svetskom nivou iznose do 10%. Bespilotne letelice (UAV) imaju široku primenu u hemijskoj zaštiti useva, ali je za sada efikasnosti herbicida primenjenih pomoću UAV nedovoljno ispitana. Cilj ovog rada bio je da se ispita mogućnost upotrebe bespilotne letelice za primenu kombinacije herbicida tritosulfuron i florasulam u zaštiti pšenice od korova. Efikasnost navedene kombinacije herbicida ispitana je u slučaju primene pomoću UAV, kao i pomoću rataske prskalice. Kombinacija herbicida tritosulfuron i florasulam primenjena pomoću UAV (norma tretiranja 30 l ha-1) je ispoljila visoku efikasnost u suzbijanju korovskih vrsta Capsella bursa-pastoris, Lactuca serriola, Sinapis arvensis i Viola arvensis, dok je efikasnosti iste kombinacije bila niža u slučaju primene ratarskom prskalicom. Na osnovu rezultata ogleda koji su ukazali na dobru efikasnost herbicida, možemo zaključiti da je sa aspekta uspešnosti zaštite pšenice od korova, upotreba UAV sasvim opravdana.

Procenjeno je da će do 2050. godine svetska populacija dostići 9,8 milijardi ljudi, što će uticati i na povećanu potražnju hrane, a što će biti teško zadovoljiti sa trenutim proizvodnim sistemom. Faktor koji otežava proizvodnju hrane su klimatske promene, a jedan od glavnih izazova za povećanje proizvodnje predstavlja upravljanje korovima. Korovi uzrokuju značajne gubitke prinosa useva širom sveta, a primena herbicida je trenutno primarna mera za njihovo suzbijanje. Razvoj dronova (bespilotnih letelica) u značajnoj meri je olakšao upravljanje korovima. Glavna prednost primene dronova u hemijskoj zaštiti useva jeste smanjenje štetnog uticaja pesticida na životnu sredinu, ali i na samog rukovaoca. Takođe, jedna od prednosti je i smanjena norma tretiranja, koja može biti smanjena i do deset puta u odnosu na ratarsku prskalicu. Cilj ovog rada je bio da se ispita efikasnost herbicida Biathlon 4D primenjenog dronom novije generacije u suzbijanju korova u usevu pšenice. Tokom 2022. godine ispitivan je efekat dve tehnike primene herbicida u suzbijanju korova u usevu pšenice. Prva tehnika je podrazumevala primenu dronom (DJI Agras T30) pri normi tretiranja od 30 l ha-1 dok je druga tehnika podrazumevala primenu traktorske prskalice pri normi tretiranja od 200 l ha-1. Osim toga, u ogled je bila uključena i kontrolna parcela bez primene herbicida. Ogled je izveden u usevu pšenice sorte Sofru-RWA, na lokalitetu Ugrinovci (opština Zemun), u fenofazi početak vlatanja (BBCH 29-31). Isti herbicid, preparat Biathlon 4D (tritosulfuron (714 g kg-1) + florasulam (54 g kg-1), WG, BASF, Nemačka) je primenjen u oba tretmana, u količini od 0,05 kg ha-1 uz dodatak okvašivača ES Plus (izodecil alcohol etoksilat (900 g l-1), SL Chemical Agrosava, Srbija) u količini od 0,2 l ha-1.Ogled je postavljen prema standardnoj EPPO metodi. Neposredno pred primenu herbicida utvrđena je zastupljenost korovskih biljaka na eksperimentalnoj parceli. Ocena efikasnosti je obavljena 16. i 31. dan nakon primene

Maintaining modern intensive plantations requires the latest practical and theoretical knowledge, the application of which achieves top-quality production results. In recent years, more and more attention has been paid to both energy efficiency and environmental aspects as the ultimate goal of the sustainability of each production. The sustainability of a process can limit reaching the maximum of said process. In the technologies of soil maintenance in perennial plantations in recent years, it becomes imperative that the chemical treatment of the soil, immediately adjacent to the plant and within the row, be replaced by mechanical processing. This need is primarily aimed at minimizing the use of pesticides in order to respond to the environmental requirements. Regular land cultivation is a technically complex problem. The given area is made up of up to 25% of the total land area of the plantation. The paper presents the results of testing a rotary harrows with a deflection, which in one pass achieves the processing of a part of the inter-row surface and half of the protective zone. The results of the research show that the optimal speed of movement of the aggregate carried out in the plantation of the orchard is 1,56 m/s, and in the plantation of the vineyard 1,23 m/s. Productivity of aggregates in the orchard 0,24 ha/h, in the vineyard 0,19 ha/h. Fuel consumption in the vineyard 7,2 l/ha, and in the orchard 6,8 l/ha. Productivity of the aggregate is largely conditioned by the technical solution of the aggregate and the technology of plantation cultivation.

Agriculture represents the traditional and least digitized industry, both in the Republic of Serbia and in the world. This situation presented an opportunity for the emergence and accelerated development of the AgTech industry, which is currently one of the fastest growing industries in the world, and is among the three most represented in the Serbian startup ecosystem. AgTech is a new generation industrial field that improves agriculture and the food industry, where the use of modern technologies to develop innovations, new business models and processes, as well as digitization and digital transformation of the industry. AgTech refers to hardware, software, business model, new technologies, new technical solutions, which are directed towards the digital space based on data collection, processing and analysis, as well as decision support tools. This paper presents the results of research conducted on a sample of 106 companies from the AgTech ecosystem in the Republic of Serbia during 2023., among which 85.7% of companies developed their innovations in cooperation with scientific institutions. The analysis of the needs of AgTech companies presented in this paper can be very important for the improvement and development of cooperation between the economy and scientific/research organizations in the Republic of Serbia, as well as the acceleration of scientific research and further commercialization of innovations and the successful transfer of technologies in this area.

Modern management of sustainable agriculture requires fast information about the condition of cultivated plants and a quick response to unwanted phenomena such as the appearance of pests in crops. According to the areas on which it is grown wheat occupies the first place in Serbia while the European Union is the world’s largest producer of wheat. However, the technology of wheat production is demanding, especially in extreme climatic conditions such as large oscillatory changes in temperatures and rainfall during the year. The appearance of insects in wheat crops can cause significant crop damage and yield reduction, especially if protection measures are not implemented in a quality manner, in a timely manner, i.e. in the initial stages of insect development. A pest that can cause a significant reduction in wheat yields is the cereal leaf beetle (Oulema melanopus). The cereal leaf beetle feeds on leaves that remain bitten in the form of stripes while the larvae bite only the upper layer, which leads to the appearance of white elongated lines. Due to the decrease in leaf mass, there is also a decrease in the yield of wheat. In Serbia, chemical protection of wheat is most often applied using field sprayers, which recently often show insufficient effectiveness in protecting wheat. Modern pesticide application techniques involve the use of unmanned aerial vehicles (UAVs). Their main advantage compared to conventional field sprayers is the achievement of higher performance as well as better distribution of pesticides on the targeted surface, which results in greater efficiency and flexibility. The aim of this research was to examine the effectiveness of insecticides in controlling the cereal leaf beetle using two different techniques, unmanned aerial vehicles and field sprayer. The insecticide that was used in this research with an unmanned aerial vehicle showed a high efficiency, namely 3 DPT - 94.67%, that is, 97.46% - 9 DPT.

Evaluating maize genotypes under different conditions is important for identifying which genotypes combine stability with high yield potential. The aim of this study was to assess stability and the effect of the genotype–environment interaction (GEI) on the grain yield traits of four maize genotypes grown in field trials; one control trial without nitrogen, and three applying different levels of nitrogen (0, 70, 140, and 210 kg ha−1, respectively). Across two growing seasons, both the phenotypic variability and GEI for yield traits over four maize genotypes (P0725, P9889, P9757 and P9074) grown in four different fertilization treatments were studied. The additive main effects and multiplicative interaction (AMMI) models were used to estimate the GEI. The results revealed that genotype and environmental effects, such as the GEI effect, significantly influenced yield, as well as revealing that maize genotypes responded differently to different conditions and fertilization measures. An analysis of the GEI using the IPCA (interaction principal components) analysis method showed the statistical significance of the first source of variation, IPCA1. As the main component, IPCA1 explained 74.6% of GEI variation in maize yield. Genotype G3, with a mean grain yield of 10.6 t ha−1, was found to be the most stable and adaptable to all environments in both seasons, while genotype G1 was found to be unstable, following its specific adaptation to the environments.

Pravac razvoja poljoprivredne proizvodnje utiče na ubrzani razvoj mašina za hemijsku zaštitu bilja. Primena savremene tehnike za hemijsku zaštita bilja ogleda se u povećanju održivosti poljoprivrede, proizvodnji zdravstveno bezbedne hrane i bezbednosti ljudi uz težnju da se smanji zagađenje životne sredine. Trenutno, navedeni trend razvoja prate bespilotne letelice (UAV), koje imaju sve veću upotrebu u hemijskoj zaštiti bilja. Cilj ovog rada bio je da se ispita mogućnost upotrebe bespilotne letelice za aplikaciju insekticida u zaštiti pšenice od ekonomski značajne štetočine, Oulema melanopus. Tokom 2022. godine ispitivali smo efekte dve tehnike aplikacije alfa-cipermetrina u suzbijanju žitne pijavice (O. melanopus). Prva tehnika aplikacije podrazumevala je tretiranje bespilotnom letelicom (DJI Agras T30) pri normi tretiranja od 30 L/ha. Druga tehnika izvedena je primenom traktorske prskalice pri normi tretiranja od 150 L/ha. Ogled je izveden u usevu pšenice sorte Sofru-RWA, na lokalitetu Ugrinovci (opština Zemun), u fenofazi početak cvetanja (BBCH 61). Alfa-cipermetrin (Fastac 10 EC, 100 g a.s./L), primenjen je u 76 preporučenoj količini primene od 150 ml/ha preparata. Ogled je postavljen prema delimično prilagođenoj standardnoj EPPO metodi PP 1/236 (1). Veličina ogledne parcele iznosila je 20 m x 60 m, sa izolacionim pojasom između tretmana od 10 m. Ocene brojnosti larvi žitne pijavice vršene su u 3 termina i to: neposredno pre tretiranja, tri dana posle tretiranja (3 DPT) i devet dana posle tretiranja (9 DPT). Efikasnost insekticida utvrđena je prema Henderson-Tiltonovoj formuli. Alfa-cipermetrin je ispoljio veoma slabu efikasnost (17,70% 3 DPT; 8,97% 9 DPT) u suzbijanju O. melanopus, kada je primenjen traktorskom prskalicom pri smanjenoj normi tretiranja od 150 L/ha. Međutim, primenjen pomoću bespilotne letelice, iako u višestruko manjoj normi tretiranja (30 L/ha), ovaj insekticid je ispoljio visoku efikasnost u suzbijanju žitne pijavice i to 3 DPT – 94,67%, odno

Chemical protection is an indispensable agro-technical step in all segments of conventional agricultural production. The significance of proper chemical protection is large for the quality and yield of cultivated culture, as is the financial costs that this measure has in the structure of total costs. The established technique of control, monitoring the quality of work and the efficiency of plant protection machines in crop production has numerous shortcomings. Different techniques of precision agriculture enable us to record and detect critical points in various production processes, so similar techniques can be applied in the control of chemical protection of barley. In this paper, a location database of actual flows of sprinklers that used chemical treatments in barley was used. On a plot of 52 ha, the deviation from the specified treatment rate by more than 10% was performed at 3.61 ha. It was found that the achieved norm of treatment when using the same aggregate, depends significantly on the operator itself, where the deviations in individual treatments and over 100%. Significant deviations in treatment standards have been identified that also significantly affect the cost of consumed chemicals, where the recommended standards have been exceeded in the chemical protection of barley production on over 454 ha, which increased the cost of used chemicals by 10.33%., Hemijska zaštita je nezaobilazna agrotehnička mera u svim segmentima konvencionalne poljoprivredne proizvodnje. Značaj pravilnog izvođenja hemijske zaštite na kvalitet i prinos gajenih useva je veliki, isto kao i finansijski troškovi koja ova mera ima u strukturi ukupnih troškova. Ustaljena tehnika kontrole, praćenje kvaliteta rada i efikasnosti mašina za zaštitu bilja u ratarskoj proizvodnji ima brojne nedostatke. Različite tehnike precizne poljoprivrede NAM omogućavaju evidentiranje i detekciju kritičnih tačaka u različitim proizvodnim procesima, pa se slične tehnike mogu primeniti u kontroli hemijske zaštite ječma. U ovom radu je korišćena lokacijski notirana baza podataka ostvarenih protoka prskalica koje su radila hemijski tretmane u ječmu. Na parceli veličine 52 ha, odstupanje od zadate norme tretiranja, za više od 10%, je obavljeno na 3,61 ha. Utvrđeno je da ostvarena norma tretiranja, prilikom korišćenja istog agregata, u značajnoj meri zavisi od samog rukovaoca, gde su odstupanja u pojedinim tretmanima i preko 100%. Utvrđena su značajna odstupanja u normama tretiranja koja značajno utiču na cenu koštanja utrošenih hemijskih sredstava, gde su u hemijskoj zaštiti ječma na preko 454 ha prekoračene zadate norme, što je povećalo troškove upotrebljenih hemijskih sredstava za 10,33%.

The effective implementation of chemical protection in fruit and grapevine production is possible with use of technically correct orchard sprayer. The paper presents the results obtained during the control testing of 41 different models of orchard sprayers, with different period of exploitation in agricultural holdings across Serbia that are used in intensive fruit and viticultural production. During the control testing, a large number of parameters were monitored, using standardized methods and test procedures. What is specifically analyzed in this paper is the technical correctness of the manometer as a corrective device of the Measuring regulatory system of the orchard sprayer. Checking the correctness of the manometer ensures the appropriate working pressure of the liquid in the designed range, which significantly improves the quality of chemical protection and extends the life of the nozzle. Out of the total number of investigated orchard sprayers, 31% are in exploitation for less than three years, while the largest number of orchard sprayers ie. 44% is in exploitation for seven years or more. The technical correctness of the manometer group 1 is at a high level (Cta= 0.80) compared to other groups of tested orchard sprayers. Group 2 and group 3 have an identical coefficient of technical accuracy of the manometer (Cta = 0.66 - 0.68). Low coefficient of technical accuracy of the orchard sprayers manometer (Cta = 0.38) occurs in group 4, which shows the direct dependence of the technical correctness of the manometer on the period of exploitation of the orchard sprayer.

The application of precision agriculture in chemical plant protection enables the realization of high yields while preserving natural resources. The quality of chemical applications depends on the type of technical system that performs for this job. The task of the technical system is to protect the cultivated crop precisely, economically and while preserving the environment, and all that depends on the precission and the quality of application of the protective liquid. The use of UAV´s in chemical plant protection enables precise application of protective liquid, so their application is increasing in the protection of numerous crops. The same trend has been observed in field production, where the use of UAV´s is on the rise. The paper compares the exploatational and technological characteristics of the field sprayer (FS) and unmanned aerial vehicle (UAV) in the chemical protection of wheat. The amount of deposited protective liquid on plants and losses of deposited on the surface of the earth were monitored. Using UAV (T4: V = 3 m·s-1 , H = 1 m), the amount of protective liquid on the plant was determined to be 0.185 mg·l-1 compared to 0.037 mg·l 1 at FS, while the losses were 0.01 mg·l-1 at FS and 0.085 mg·l-1 at UAV. The presence of Fusarium (Fusarium spp.) after chemical protection was analyzed according to the compared technical systems and set treatments. It was recorded for 20% higher efficiency in protection against Fusarium (Fusarium spp.) using UAV (T5: V = 3 m·s-1 , H = 2 m) compared to FS. The values of wheat yield were measured according to the compared technical systems and set treatments, where the highest wheat yield was achieved using UAV (T5) with 10,667.7 kg·ha-1 , while using FS, 14.84% lower yield was achieved. The application of UAV´s in the segment of chemical plant protection enables us to effectively protect crops, economical and optimized production, while preserving the environment in a way that has been completely new and unknown until no

Hay is a bulky part of the meal that is most often used in the winter period of the year in all types of ruminants, while the role of hay in the meal of high-milk cows is invaluable. The most common way to produce hay is to dry the cut grass on the surface of the land in the field, using the energy of the sun. In the process of hay production, there is a reduction of nutrients in relation to the green mass, where the achieved yield and quality of hay largely depends on the technological operations that are performed during storage. In the baling process, the dried mass is exposed to the mechanical treatment of the working elements of the press, as a result of which the leaf mass decreases. Loss of leaf mass, which contains a large amount of nutrients, can greatly affect the achieved yield and quality of the obtained hay. One of the possibilities to reduce losses is the application of "DewPoint" technology, which involves the use of water vapor in the baling process. The steam produced by the device is injected into the mass-hay after lifting by the pickup device and further until the mass enters the pressing chamber. Mass treatment is achieved by injecting steam through a series of nozzles located inside the press. Water vapor is an extremely efficient medium for the controlled hydration of hay during the baling process, where approximately 450 l of water vapor can be produced from 1 l of water. By applying this technology, water consumption is 5-7 l per 1 t of hay, producing 2250-3150 l of water vapor. This amount of steam enables efficient treatment of individual plants (tree, leaf) in a mass of 1t to the desired humidity level.

Performing works with the land where a lot of mechanical work is engaged, such as making pits for planting fruit, needs to be mechanized. This replaces human labour with a tractor machine aggregate with an increase in productivity and thus makes the process cheaper. For the proper selection of individual means of mechanization, it is important to determine the optimal agrotechnical parameters of their application. Proper selection and use of mechanization tools for planting have a decisive influence on the intensity and progress in cultivation technology. Defining energy and exploitation parameters of tractor-machine aggregates during mechanized construction of pits is the subject of this research. The pits are intended for individual planting of fruit seedlings as well as the installation of trellis poles. The test results of the tractor-machine aggregate show that the lowest driving force engaged for drilling was achieved in the field and was 6.36 kW for the excavated pit with the depth of 885 mm and with a diameter of 520 mm, the number of revolutions of the drill was 93 rpm and drilling was achieved in 27 s. The highest driving force for drilling was engaged in field III, which was 30.8 kW for the excavated pit 780 mm deep with a diameter of 490 mm, the number of revolutions of the drill bit was 111 rpm and drilling was realized in 30 s. The results obtained in these tests show that the consumption of motor power largely depends on the type of soil, the quality of previous soil preparations and the number of revolutions of the tractor PTO shaft. The time required to move the aggregate from one to the next drilling site is crucially influenced by the terrain configuration, the state of soil preparation and the skill of the tractor driver and auxiliary worker.

Agricultural industry is essential for humanity. It provides it with food, fibers, fuel and raw materials that are necessary for a normal living. As the technology advance, it is vital to see how the same technology can be implemented in other industries. With the development of Industry 4.0, many industries are trying to implement new technologies. Industry 4.0 represents the current peak of industry development. Today there are demands in various industries for shorter delivery and production time, more efficient, cost efficient and automated processes. The technology of Industry 4.0 can be applied to agricultural industry as well. Improvements of agricultural machineries in terms of electronic, sensors to enhance their current performances. Using electronics, sensors and drones, supports the data collection of agriculture key aspects, such as crops behaviour, weather, animals etc. The main task is how to implement the right methods in order to enhance agricultural industry with the help of Industry 4.0.

Biogradska Gora National Park in Montenegro is part of the Bjelasica Mountain which belongs to the montane region of the Dinaric Alps. Biogradska Gora is one of the largest long-term preserved forests in the Southeast Europe. In this paper there were compared the main structural characteristics of the old-growth mixed forest of spruce (Picea abies L.), fir (Abies alba L.) and beech (Fagus moesiaca (Domin, Maly) Czecz.), from the preserved area of the Biogradska Gora, with similar managed forests from the same mountain. Basic insight into the structural characteristics of forests of spruce, fir and beech was obtained by analyzing tree species composition and two basic structural elements - number of trees and wood volume per unit area. The obtained data provides overview of the structural characteristics of these forests. The results revealed the production potential of the studied mixed forests. The average quantity of standing volume in old-growth forests of Biogradska Gora indicates very valuable and productive forest ecosystems. Presented data shows that forest ecosystems of spruce, fir and beech in the protected area of the National Park Biogradska Gora are characterized by structurally irregular forests with presence of old trees with relevant growing stock and optimal balance of beech and conifer species, while in managed forests on the same mountain, growing stock is very low and with structure which is far from optimal.

The aim of this research was to study the impact of application technique and rate of liquid starter fertilizer applied with a novel device on the production of corn. Starter fertilizer was applied in the root system range of freshly germinated plants in the 'belt' and 'point' forms at different quantities (35, 50, 70, and 100 L ha(-1)), which led to intensive plant growth in the initial stages of development. This adapted system was used for sowing and for application of the liquid starter fertilizer at the same time. The field trial was set up at two sites (two different land types), in the conditions of the natural water regime of the soil during the three vegetation seasons in the period 2016-2018. For this purpose, a prototype of the electronic device EUKU-01 was designed. The starter fertilizer was applied at 5 cm laterally from the row where the sowing was performed and 5 cm below the depth at which the corn seeds were sown. Data were statistically analyzed by two-factor analysis of variance, where the influence of mineral fertilizer treatment and the influence of liquid starter fertilizer treatment were observed as factors. The results showed that the optimal choice of the technique of liquid starter fertilizer application can result in fertilizer savings by 30% without reducing yield.

The aim of this research is to study the drying kinetics of vacuum-dried and freeze-dried bee honey produced from two different varieties: Sunflower honey (Helianthus Annuus L.) and Acacia honey (Robinia pseudo acacia L.). Vacuum drying treatments were carried out with the honey samples' initial temperatures of +25 degrees C, -20 degrees C, and -40 degrees C. Water content, total soluble solids, as well as the water activity of fresh and dried honey samples were determined. Freeze-drying of bee honey with initial sample temperature of -40 degrees C has resulted in shorter drying time (7-9 hours), moisture content (10%-12%), water activity (0.405-0.427 aW) and effective moisture diffusivity coefficient (8.26.10-7-9.51.0-7 m(2)/s). The high-performance liquid chromatography method was used when analyzing the impact that drying pre-treatments had on honey quality. The application of pre-treatments has led to an increase in hydroxy-methyl-furfural by 39-71%, and a decrease in diastase activity by 17-36%, all compared to fresh honey samples. The solutions of Verma model proved to be the best fit with the experimental results.

Basic soil tillage in perennial plantations is still present in agro-ecological conditions of R.Serbia despite the tendency for grassing the inter-row space. The reasons for this include arid climatic conditions, as well as the lack of an irrigation system requiring great investments. Mechanical soil tillage provides some advantages over the procedures of soil grassing. These advantages primarily relate to the rational distribution of moisture in the soil, prevention of the development of harmful rodents, better aeration of soil as well as an effective application of organic fertilizers. The paper presents comparative exploitation surveys in soil tillage with a conventional plough, subsoilers and rotary hoes in perennial plantations. The exploitation testing covered determination of working depth, working speed, pulling resistance, front and rear wheel load, performance and fuel consumption. The results of the survey show that apart of having better tractor static load distribution when it is in aggregate with the rotary hoe, this combination has a potential of lowering the fuel consumption. This aggregate has 17% lower fuel consumption compared to the subsoiler usage and 29% lower consumption compared to the plough usage. The main conclusion is that the performance indicators of the working methods described should be analysed in further research. To-date experience shows that the operation of the rotary hoe compared to the standard plough results in lower intensity of the soli mixing and lower intensity of plant residues incorporation in the soil., Osnovna obrada zemljišta u višegodišnjim zasadima i pored tendencija zatravljivanja međurednog prostora još uvek je prisutna u agroekološkim Republike Srbije. Razlog za to su aridni klimatski uslovi kao i nedostatak tehničkih sistema za navodnjavanje za čije korišćenje su potrebne velike investicije. Mehaničkom obradom zemljišta ostvaruju se određene prednosti u odnosu na postupke zatravljivanja. Te prednosti pre svega se odnose na racionalnim raspolaganjem sa vlagom u zemljištu, sprečavanje razvoja štetnih glodara, bolja aeracija zemljišta, kao i efikasno unošenje organskih đubriva. U radu su prikazana uporedna eksploataciona istraživanja pri obradi zemljišta klasičnim plugom, razrivačem i rotacionim ašovom u višegodišnjim zasadima. Ispitivanjima su obuhvaćeni parametri: dubina obrade, vučni otpor, oterećenje prednjih i zadnjih točkova, brzina kretanja, učinak i potrošnja goriva. Rezultati istraživanja u ovom radu pokazuju da pored bolje statičke raspoređenosti opterećenja traktora u radu agregata traktor - rotacioni ašov u odnosu na obradu oranjem i razrivanjem, značajne su i uštede u potrošnji goriva po jedinici površine. Potrošnja goriva kod obrade rotacionim ašovom je manja za oko 17 % u odnosu na podrivanje i do 29 % u odnosu na oranje klasičnim plugom.

Vegetation cover change in all the river basins leads to the changes of hydrologic response, soil erosion and sediment dynamics characteristics. Those changes are often viewed as main cause of anthropogenic and accelerated erosion rates in short term and one of the main reasons of climate change in long term. The effects of vegetation cover changes on various parts of water balance and hydrological cycle has to be deeply studied because of its important role on mankind future. The aim of present research was therefore to simulate the responses of soil erosion processes by using a process-oriented soil erosion model IntErO, with the different settings of land use for the years 1977, 1987, 1997, 2006 (2007) and 2016 (2017) in Orahovacka Rijeka watershed; a pilot river basin of the Polimlje Region for the northeastern part of Montenegro. For the current state of land use, calculated peak discharge for the Orahovacka Rijeka was 174-175 m(3) s(-1) (the incidence of 100 years) and there is a possibility for large flood waves to appear in the studied basin. Real soil losses, Gyear, were calculated on 2614-2921 m(3) year(-1), specific 229-256 m(3) km(-2) year(-1) (1977-2017). The value of Z coefficient range from 0.444 to 0.478 and indicates that the river basin belongs to III destruction category. The strength of the erosion process is medium, and according to the erosion type, it is surface erosion. According to our analysis the land use changes in the last 40 years influenced the increase of the soil erosion intensity for 11% in the study watershed. Further studies should be focused on the detailed analysis of the land use changes trends with the other river basins at the national level, closely following responses of soil erosion to the changed land use structure. The results and approach also should be used by policymakers in all national natural resources organizations to highlight the role of management.

When it comes to fruit and wine production, one of the serious problems for many producers in Serbia is the frost. Frost occurs in a relatively short period of time and, depending on the timing and intensity, can cause greater or less damage to the cultivated crop. Damage can be reflected in a significant decrease in the crop in the current production year, but in addition, the damage can also have a long-term character., Kada je u pitanju voćarsko - vinogradarska proizvodnja jedan od ozbiljnih problema koji muči mnoge proizvođače u Srbiji jeste mraz. Mraz se javlja u relativno kratkom vremenskom periodu i zavisno od vremena javljanja i intenziteta može naneti veće ili manje štete gajenoj kulturi. Štete se mogu ogledati u značajnom umanjenju roda u tekućoj proizvodnoj godini, ali pored toga štete mogu imati i dugoročni karakter.