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Kila kupusa – da li predstavlja opasnost?
Get PDFThe causal agent of cabbage clubroot, historically is one of the oldest diseases and today is getting more and more important. The reason for this is primarily increase the area under brassicas, short crop rotation or rotation within the same family, as well as the difficulty in pathogen control. In recent years there has been a more intensive appearance of this pathogen at locations where brassicas is traditionally grown, but also on new ones which indicate its spread. Certain control measures slowly lose their importance, while respecting crop rotation as basic measures are often ignored. Everything indicates that cabbage is a threat and that it is necessary to apply all hygienic and sanitary measures in order to stop the pathogen.Kila kupusa, istorijski gledano kao jedno od najstarijih oboljenja, danas dobija sve više na značaju. Tome pre svega doprinosi povećanje površina pod kupusnjačama, kratka rotacija useva ili rotacija u okviru iste familije, kao i otežano suzbijanje patogena. Poslednjih godina dolazi do intenzivnije pojave ovog patogena na lokalitetima gde se tradicionalno gaje kupusnjače, ali i na novim, što ukazuje na njegovo širenje. Pojedine mere u suzbijanju polako gube na značaju, a poštovanje plodoreda kao osnovne mere često se zanemaruje. Sve izneto ukazuje da kila kupusa predstavlja opasnost i da je blagovremeno potrebno primeniti pre svega sve higijensko-sanitarne mere kako bi se patogen zaustavio
Ventili kao upravljačke komponente hidrostatičkih sistema
Get PDFModern agricultural engineering involves the wide application of hydraulic and pneumatic systems for the transmission of power (energy) and control signals. This paper presents the most commonly used types of valves in hydraulic systems. In the literature, more classification of hydraulic valves is reported, according to their construction, purposes, etc., which, even within the same classification criteria, sometimes stronglu differ one from the another. Therefore, this presentation is organized by principled valve assignment into four basic groups based on purpose, although there are other divisions according to the purpose of the valve. Other classifications, although present in the available literature, have not been commented in detail, due to space constraints. In this manuscript, the basic elements of the construction of the most important types of valves are described and analyzed, their most important characteristics are described, the base functional principles and technical limitations described, and the given guidelines and recommendations for their optimal application.Efikasnu, ekonomičnu i samoodrživu savremenu poljoprivrednu tehniku teško je, pored niza drugih agroekoloških, tehničkih ekonomski i drugih zahteva, zamisliti bez širokog uključivanja manuelnih, mehaničkih, hidrauličkih, pneumatskih, električnih, analognih i digitalnih sistema upravljnja, kao i njihovih usklađenih međusobnih aktivnosti vezanih za prenos snage (energije) i upravljačkih signala. U ovom radu su prikazani najčešće korišćeni tipovi ventila u hidrauličkim sistemima. Literatura prikazuje više klasifikacija ventila, prema konstukciji, nameni itd., pri čemu se čak i isti tip ventila nekada svrstava u različite grupe. Zato su nekada i ventili svrstani u okviru istog klasifikacionog kriterijuma, mogu međusobno značajno razlikovati. Iz navedenih razloga, ovaj prikaz je organizovan principijelnim svrstavanjem ventila u četiri osnovne grupe, prema osnovnim namenama, mada postoje i drugačije podele prema nameni ventila. Ostale klasifikacije, prisutne u dostupnoj literaturi, samo su preliminarno komentarisane. U ovom radu su opisani i analizirani osnovni elementi konstrukcije najvažnijih tipova ventila, navedene njihove najbitnije tehničko-operativne karakteristike, opisani bazni funkcionalni principi i tehnička ograničenja, te date smernice i preporuke za njihovu optimalnu primenu u poljoprivrednoj tehnici
Karakteristike krvnih ćelija Sabanejewia balcanica (Cobitidae) iz nekih tekućica slivnog područja rijeke Save
Get PDFThe research deals with the analysis of the morphological characteristics of the blood cells and the differential leucocytes count in the Balkan spined loach (Sabanejewia balcanica) from eight locations of the Sava River. In the study, 39 blood smears of individuals collected from the Turija, Gostelja, Oskova, Brka, Suturlija, Suha, Tinja and Trebačka Rivers were analyzed. The blood smears were stained by the Pappenheim method and were analyzed at the magnification 100x. The information on the hematological characteristics of this species is scarce. Thus, this research will serve as a basis for further and more complicated hematological researches. Taking into account the fact that in many countries the investigated species is described as a sensitive or endangered species, it is necessary to establish and preserve its natural habitats and to know their ecological characteristics whose effects can be determined by studying their hematological status.Ovo istraživanje obuhvatilo je analizu morfoloških karakteristika krvnih ćelija, kao i diferencijalnu krvnu sliku balkanskog zlatnog vijuna (Sabanejewia balcanica) sa osam lokaliteta slivnog područja rijeke Save. Analizirano je 39 krvnih razmaza jedinki prikupljenih iz rijeke Turije, Gostelje, Oskove, Brke, Suturlije, Suhe, Tinje i Trebačke. Preparati su bojeni metodom po Pappenheim-u i mikroskopirani pod imerzionim objektivom. Hematološke karakteristike ove vrste su nedovoljno proučene, tako da sprovedeno istraživanje može poslužiti kao osnova za dalja i kompleksnija hematološka istraživanja. Istraživana vrsta je u mnogim zemljama opisana kao osjetljiva ili ugrožena vrsta. Zbog toga je potrebno je utvrditi i sačuvati njena prirodna staništa i upoznati njihove ekološke karakteristike čiji efekti se svakako mogu konstatovati proučavanjem njihovog hematološkog statusa
Content of Phosphorus in Arable Land on the Teritory of the City Of Nis
Get PDFPhosphorus has the status of an essential element for plant growth and development because it is contained in numerous compounds which are of the crucial significance for the physiological –biochemical processes. The aim of this paper was to examine the saturation of the soil with easily available phosphorus forms on the territory of the city of Nis in 2015. The total of 284 samples from 110 farms were collected. The analysis showed that that the soil of this area is well provided with easily available phosphorus. 40.8% samples belong to the class of supplied or even well-supplied soil, with the phosphorus content from 7% to 15% whereas only 5% of the samples belong to the class of the soil low in phosphorus
Mikrobiološki kvalitet mesnih prerađevina i analiza radnih površina
Get PDFThe microbiological safety and quality of meat products are important to producers and consumers and involve microbial contaminants on the final products. The swabs were obtained from workers hands, plank for meat cutting, and knifes in January and February 2016. Beef and sheep prosciutto and Sudžuk sausage sampling was also performed at the same locations in the same time as swabs sampling. In these meat products, aerobic mesophilic bacteria, yeast, molds, E. coli, Salmonella spp., and clostridia were determined. Higher level of contamination was obtained in January. Workers hands were highly contaminated with all examined bacteria, while in knife swabs lowest contamination level was detected. Higher level of meat products contamination was also noticed in January 2016. Aerobic mesophilic bacteria were most abundant in Sudžuk sausage samples, E. coli, yeasts and molds in sheep prosciutto, while Salmonella spp. and clostridia were not detected in any sample. Good microbiological quality of meat products was noticed.Mikrobiološka bezbjednost i kvalitet mesnih prerađevina su veoma značajni za proizvođače i potrošače, s obzirom na potencijalnu opasnost od njihove mikrobiološke kontaminacije. Brisevi su uzimani sa ruku radnika, dasaka za sječenje i noževa u januaru i februaru 2016. godine na pijaci Vogošća-Sarajevo. Uzorci pršute, stelje i sudžuka su uzeti iz istih objekata i u isto vrijeme kad i brisevi iz tih objekata. U ovim mesnim prerađevinama, određeno je prisustvo aerobnih mezofilnih bakterija, kvasaca, gljiva, E. coli, Salmonella spp. i klostridija. Veći stepen kontaminacije radnih površina zabilježen je u januarskom uzorkovanju. Ruke radnika su bile veoma kontaminirane svim ispitivanim bakterijama, dok su noževi za sječenje bili najmanje kontaminirani. I mesne prerađevine su bile više kontaminirane u januaru 2016. godine. Aerobne mezofilne bakterije su bile najzastupljenije u sudžuku, E. coli, kvasci i gljive u stelji, a Salmonella spp. i klostridije nisu detektovane ni u jednom uzorku, pa se može zaključiti da je sigurnost mesnih prerađevina dobra
Strukturiranje ekološki prihvatljivih elastomernih kompozitnih materijala
Get PDFFor the waste rubber recycling, it is obligative to know the chemical composition of the waste products, if it is to be used in the new composite elastomeric material formulation. The composite elastomeric materials obtained from the waste rubber powder have a very diverse application (farm floors, sports stadiums, tyres production, in construction as a vibration protection material). The aim of this work was to prepare elastomeric composites based on recycled elastomer powder (REP). A few types of elastomeric materials were synthesized based on natural rubber, polybutadiene rubber, styrene-butadiene rubber, (NR/BR/SBR, 40/40/20 phr), carbon black and recycled elastomer powder were synthesized. It was assessed that composites NR/BR/SBR/REP have shorter optimum curing time tc90 than samples without REP. By increasing the REP content the tc90 value and tensile strength are decreasing, but the abrasion resistance is increasing.Kod recikliranja otpadne gume neophodno je poznavati hemijski sastav otpadnog proizvoda, ukoliko će se on koristiti u recepturama za nove hibridne elastomerne materijale. Kompozitni elastomerni materijali dobijeni od praha otpadne gume imaju veoma raznovrsnu primenu (podovi na farmama, sportski stadioni, dobijanje pneumatika, u građevinarstvu kao materijali za zaštitu od vibracija itd). Cilj ovog rada je bio da se dobiju elastomerni kompoziti na osnovu reciklirane gume. Sintetisano je nekoliko tipova elastomernih materijala na osnovu prirodnog kaučuka, stiren-butadienskog kaučuka i polibutadienskog kaučuka (NR/BR/SBR, 40/40/20 phr), čestica čađi i recikliranog gumenog praha. Ustanovljeno je da kompoziti NR/BR/SBR/REP imaju kraće optimalno vreme umrežavanja u poređenju sa uzorcima NR/BR/SBR bez REP. Porastom količine REP smanjuje se vreme optimalnog umrežavanja i prekidna črstoća, a povećava se otpornost na abraziju
Optimizacija uslova mikrotalasne ekstrakcije fenolnih jedinjenja ploda divlje trešnje (Prunus Avium L.)
Get PDFThe aim of this study was to optimize the conditions of microwave extraction for determining the content of the total flavonoids of wild cherry fruits (Prunus avium L.). The conditions that are optimized are the percent of methanol, solvent to liquid ratio, the time and temperature of the extraction. Based on the experimental design and software package Design Expert 7.0.0, the optimal conditions for this type of extraction were determined: methanol percentage 70%, solid to liquid ratio 0.03 g / mL, extraction time 1.80 min and temperature 78 ° C. Using the DPPH method, the antioxidant activity of the extract obtained under optimal conditions was determined (IC50 = 5.14 mg mL-1).Cilj ovog rada bila je optimizacija uslova mikrotalasne ekstrakcije za određivanje sadržaja ukupnih flavonoida ploda divlje trešnje (Prunus avium L.). Uslovi koji su optimizovani su procenat metanola, odnos mase uzorka i rastvarača, vreme i temperatura ekstrakcije. Na osnovu eksperimentalnog dizajna i softverskog paketa Design Expert 7.0.0., određeni su optimalni uslovi ove vrste ekstrakcije i to su: procenat metanola 70%, odnos mase uzorka i rastvarača 0,03 g/mL, vreme ekstrakcije 1,80 min i temperatura 78 °C. Primenom DPPH metode ispitana je antioksidativna aktivnost ekstrakta dobijenog pod optimalnim uslovima (IC50 = 5,14 mg mL-1)
Đorđe Radić (1839–1922) prvi Srbin koji je stekao doktorat iz poljoprivrede
Get PDFDr. Đordje Radić, one of the most educated Serbs of the 19th century, laid the foundations of scientific and educational literature in the field of agriculture, founded three agricultural schools, and in many ways improved agronomy in Serbia and Montenegro. He was an outstanding expert, who was well-informed about the agricultural situation not only in Serbia, but also in the most developed European countries. In his writing, he mostly relied on the works of German agronomists, and succeeded in writing about 50 professional books and textbooks, which served both for the education of elementary and vocational school students and as manuals for farmers. The aim of the paper is to present, through the biography of Đordje Radić, the comprehensiveness of his professional, scientific and social creativity and significance. As the first Serb to earn a Doctorate in the field of Agriculture, he was a pioneer of many branches of agronomy in Serbia. The results of his research and engagement are visible today, in both science and education. Radić's biography, the contribution to the development of education, the impact on the urbanization of Kraljevo and the list of published books are presented in the paper, which is divided into four parts.Dr Đorđe Radić, jedan od najobrazovanijih Srba 19. veka, utemeljio je naučnu i obrazovnu literaturu u oblasti poljoprivrede, osnovao je tri poljoprivredne škole, na više načina unapredivši agronomiju u Srbiji i Crnoj Gori. Bio je izuzetan stručnjak koji je poznavao poljoprivredne prilike u Srbiji, ali i u najrazvijenijim evropskim zemljama. U pisanju se oslanjao na dela uglavnom nemačkih agronoma, uspevši da napiše oko 50 stručnih knjiga i udžbenika, koji su služili i za obrazovanje učenika osnovnih i stručnih škola i kao priručnici poljoprivrednicima. Cilj rada je da se kroz biografiju Đorđa Radića predstavi sveobuhvatnost njegovog profesionalnog, naučnog i društvenog stvaralaštva i značaja. Kao prvi Srbin doktor nauka bio je začetnik mnogih grana agronomije u Srbiji. Rezultati njegovih istraživanja i angažovanja vidljivi su i danas, u nauci i prosveti. U radu, podeljenom na četiri celine, prikazani su Radićeva biografija, doprinos razvoju prosvete, uticaj na urbanizaciju Kraljeva i spisak objavljenih knjiga
In vitro razmnožavanje novih vegetativnih podloga za šlјivu
Get PDFTo determine the effect of successive subculturing on multiplication capacity of shoots, vegetative rootstocks for plum Docera, Dospina and St. Julien A were repeatedly subcultured for 5 subcultures on medium of unchanged composition. As for Docera and Dospina, significan increase in multiplication index and length of axial shoots was observed in the 3. subculture, whereupon their values gradually decreased to the 5. subculture, but remained considerabely higher in comparison with the values in the first two subcultures. Contrary, in St. Julien A shoot multiplication declined over the first three subcultures, then increased and remained at the level of the 1. subculture. Length of axial shoots was changed in the same way as for Docera and Dospina. The highest cacpacity for in vitro rooting was observed in Docera (91.7%), while the lowest was in St. Julien A (44.4%).Vegetativne podloge za šljivu Docera, Dospina i St. Julien A su umnožavane in vitro pet uzastopnih supkultura na medijumu konstantnog sastava u cilju ispitivanja uticaja sukcesivnog supkultivisanja na parametre multiplikacije. Kod podloga Docera i Dospina uočeno je značajno povećanje indeksa multiplikacije i dužine osovinskih izdanaka u 3. supkulturi, posle čega njihova vrednost postepeno opada do 5. supkulture, ali i dalje ostaje značajno veća u odnosu na prve dve supkulture. Suprotno, kod podloge St. Julien A uočen je trend pada indeksa multiplikacije od 1. ka 3. supkulturi, posle čega njegova vrednost ponovo raste i ostaje na nivou 1. supkulture. Dužina osovinskih izdanaka se tokom supkultivisanja menjala na isti način kao kod podloga Docera i Dospina. Najveći kapacitet ožiljavanja in vitro utvrđen je kod podloge Docera (91,7%), a najniži kod St. Julien A (44,4%)
Possibility for Spindle and Solaxe Trees Apple Breeding
Get PDFThe second stage of intensification of apple industry in Europe started during the early of 1970`s with Dutch `Slender spindle` training system for high density plantations. Other systems such as `Verical axis', V and Y - shaped system,`Tatura trellis`,`Solen`, `Solaxe`, `Cone` etc. were developed in different countries of the world.
Apple breeding for resistance to major diseases and for spindle and Solaxe tree architecture aims to significantly lower the total cost of fruit production. At our breeding program for resistance to scab, mildew and the aphids Dysaphis plantaginea Pass. and Aphis pomi De Geer, we selected hybrids with naturally attained spindle and Solaxe trees. In the progenies of cultivars ‘Enterprise’, ‘Freedom’, ‘Avrora’, ‘Generos’, ‘Paulared’, ‘Prima’, ‘Tavria’, ‘Pionier’ o.p. and ‘Akane’ (‘Primrouge’) × ‘Krimskoe’, ‘Akane’ × ‘Florina’, and ‘McIntosh Wijcik’ × ‘Paradox’, we found trees with a habit resembling the characteristics of the spindle training system. Plants with a weeping habit were selected from crosses of ‘Paradox’ × ‘Prima’ and ‘Elize Rathke’ × ‘Florina’, and between those hybrids a further set was selected which exhibited a natural Solaxe, the modern system for training and pruning in apple orchards