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dc.contributor.advisorTuran, Jan
dc.contributor.otherRadivojević, Dušan
dc.contributor.otherĐokić, Dragoslav
dc.contributor.otherBokan, Nikola
dc.contributor.otherBalalić, Igor
dc.creatorKoprivica, Ranko
dc.date.accessioned2018-12-27T12:16:20Z
dc.date.available2018-12-27T12:16:20Z
dc.date.available2020-07-03T15:01:50Z
dc.date.issued2018-09-07
dc.identifier.urihttp://eteze.kg.ac.rs/application/showtheses?thesesId=6071
dc.identifier.urihttp://nardus.mpn.gov.rs/handle/123456789/10516
dc.identifier.urihttps://fedorakg.kg.ac.rs/fedora/get/o:1016/bdef:Content/download
dc.description.abstractU tehnološom procesu proizvodnje uljane repice, najveći problem je određivanje pravog momenta berbe. Nepravovremena berba i nepravilna primena mašina za žetvu, pruzorkuju velike gubitke prinosa, lošiji kvalitet zrna i ulja, što umnogome umanjuje uspeh proizvodnje ove veoma značajne uljarice. Vreme berebe je povezano sa morfološkim osobinama sorti i opštim stanjem useva na proizvodnim parcelama. Pored toga, neujednačeno sazrevanje i veoma kratak period do nastupanja prezrelosti plodova, otežava određivanje pravog vremena početka, trajanja i završetka berbe. Osnovni problem u berbi uljane repice su gubici zrna koji nastaju otvaranjem ljuski, uglavnom zbog njenih nepovoljnih mehaničkih osobina, odnosno nedovoljne čvrstoće ploda na otvaranje i kršenje. U toku istraživanja ispitivane su razlike između sorti Banaćanka, Jasna i Slavica u fizičkim (dužina, širina, debljina, broj zrna i njihova masa, masa prazne ljuske, ukupna masa ljuske sa zrnom) i mehaničkim osobinama ljuski (sile kršenja i otvaranja ljuski). Merenje sile otpora otvaranja ljuski obavljeno je testom pritiska u horizontalnom položaju, kada sila deluje po poprečnoj osi normalno na širinu ljuske, kao i vertikalnom položaju, kada sila deluje po uzdužnoj osi ljuske. Maksimalne granične vrednosti sile kršenja ustanovljene su povlačenjem grančice suprutno od pravca rasta ljuske, sve do momenta odvajanja peteljke ljuske od grančice. Za potrebe eksperimenta projektovan je i realizovan uređaj sa merno akvizicionim sistemom za određivanje sile kršenja i otvaranja ljuski u horizontalnom i vertikalnom položaju. Određivanje vrednosti sile kršenja i otvaranja ljuski ispitivanih sorti uljane repice obavljeno je pri sadržaju vode u zrnu od 14,39% do 16,07% u prvom i od 9,33 % do 10,56% u drugom roku-vremenu berbe. U cilju povećanja mehaničke otpornosti na otvaranje i kršenje ljuski, tri nedelje pre berbe uljane repice folijarno je primenjen Elastiq sredstvo na bazi polimera lateksa. Vreme berbe je značajno uticalo na veličinu sile otvaranja u vertikalnom i horizontalnom položaju ljuski, pri čemu su ljuske ubrane u prvom roku berbe u proseku bile otpornije na otvaranje u odnosu na ljuske iz drugog roka berbe. Sve ispitivane sorte su u proseku imale jednaku otpornost na otvaranje u horizontalnom položaju ljuske. U vertikalnom položaju sorta Banaćanka (2,99 N) je bila otpornija na otvaranje ljuski u odnosu na sorte Jasna (2,63 N) i Slavica (2,45 N). Sila otvaranja u vertikalnom položaju ljuski povezana je sa masom prazne ljuske sa pregradom, sa širinom i debljinom ljuski, a u horizontalnom položaju ljuske sa masom zrna. Smanjenjem sadržaja vode u zrnu, odnosno sazrevanjem ljuski, sila kršenja svih sorti je opadala, jer pri tome dolazi do slabljenja spoja između peteljke ljuske i centralne grančice. Sile kršenja u vertikalnom i horizontalnom položaju ljuski u prvom roku su bile veće u odnosu na njihovu veličinu u drugom roku berbe samo kod sorti Banaćanka i Slavica. U prvom roku berbe najveća sila kršenja ljuski po vertikalnoj osi utvrđena je kod sorta Banaćanka (1,56 N) a u horizontalnom položaju, pored nje (1,38 N) i kod sorte Slavica (1,33 N). U drugom roku berbe, kod prezrelih biljaka nije bilo značajnih razlika u vrednostima sile kršenja ljuski između sorti. Vrednosti sile otvaranja ljuski su veće od sila kršenja u vertikalnom i horizontalnom položaju ljuske kod svih sorti u oba roka roka berbe na obe varijante primene Elastiq-a. Folijarna primena Elastiq-a, sredstva za poboljšanje mehaničkih osobina ljuski, uticala je na povećanje otpornosti na otvaranje ljuski kod svih sorti u horizontalnom i vertikalnom položaju ljuske. Pored toga, primena Elastiq-a je uticala na povećanje otpornosti na kršenje u horizontalnom položaju ljuski kod svih sorti, a u vertikalnom položaju samo kod sorte Banaćanka. Pored određivanja vrednosti mehaničkih osobina ljuski, ispitivane su i fizičke osobine zrna sorti uljane repice pri različitim sadržajima vode u zrnu (6%,11%,16% i 21). Fizičke osobine: masa 1000 zrna, zapremina, poroznost, statički i dinamički ugao nasipanja i koeficijent statičkog trenja zrna povećavale su se, a vrednosti gustine i nasipne mase zrna su se smanjivale sa porastom sadržaja vode u zrnu. Sorte su se razlikovale u pogledu vrednosti svih fizičkih osobina u obe godine, osim gustine, nasipne mase i poroznosti zrna u 2015.godini. Sorta Jasna je u prvoj godini ispitivanja imala najveću masu 1000 zrna i zapreminu zrna, kao i najmanju poroznost, nasipnu masu i gustinu zrna u obe godine. Najveći statički i dinamički ugao nasipanja zabeležen je kod sorte Slavica. Pri bilo kom sadržaju vode u zrnu, najveći koeficijent statičkog trenja bio je na podlozi od šper ploče, zatim plastike, aluminijumskog, čeličnog i pocinkovanog lima, a najmanji na podlozi od nerđajućeg čeličnog lima. Koeficijent statičkog trenja na svim podlogama i pri svim sadržajima vlažnosti zrna sorte Banaćanka bio je manji u donosu na sorte Jasna i Slavica.sr
dc.description.abstractThe main issue in rapeseed production technology is the proper timing of harvest. Untimely harvest and improper use of harvesting machinery cause huge crop losses and a reduction in seed and oil quality, thus negatively affecting the production of rapessed as a highly important oilseed crop. Harvest date is associated with the morphological properties of cultivars, as well as with the overall state of the crop in the field. Moreover, non-uniform ripening and a very short period before the fruits enter the overripe stage hamper the timing of the onset, duration and termination of harvest. The main rapeseed harvest problem is seed loss due to pod shatter, mostly as the result of unfavourable mechanical properties i.e. insufficient shatter and rupture strength of pods. During the research, cvs. ’Banaćanka’, ’Jasna’ and ’Slavica’ were tested for differences in the physical properties of pods (pod length, pod width, pod thickness, number of seeds, seed weight, weight of pods without seeds, total weight of pods with seeds) and mechanical properties of pods (pod shatter force and pod rupture force). Pod shatter resistance force was measured by the pressure test in the horizontal direction, involving an action of the force along the transverse axis normal to pod width, as well as in the vertical direction, with the force applied along the longitudinal axis of the pod. Maximum pod rupture force values were established by pulling the twig in the direction opposite to that of pod growth until the pedicel was detached from the twig. The experiment involved the design and use of a device comprising a data measurement and acquisition system for the determination of the pod shatter and rupture force applied in both horizontal and vertical direction. Pod shatter and rupture force values for the tested rapeseed cultivars were determined at seed moisture ranging from 14.39% to 16.07% at the first harvest date, and from 9.33 % to 10.56% at the second harvest date. To increase mechanical shatter and rupture resistance, the rapeseed crop was foliarly treated with the polymer latex-based product Elastiq three weeks before harvest. Harvest date had a significant effect on shatter force in both vertical and horizontal pod direction, with the pods harvested at the first harvest date showing higher average shatter resistance than those at the second harvest date. Pod resistance to shatter along the horizontal axis was identical on average in all cultivars. Along the vertical axis, cv. ’Banaćanka (2.99 N) was more resistant to pod shatter than ’Jasna’ (2.63 N ) and ’Slavica’ (2.45 N). Pod shatter force along the vertical axis was dependent on the weight of an empty pod with a septum, as well as on pod width and pod thickness. Along the horizontal axis, it depended on seed weight. As the seed moisture content decreased i.e. as pods ripened, the rupture force in all cultivars decreased due to the weakened union of the pedicel with the central twig. Rupture forces along the vertical and horizontal pod axes were higher at the first harvest date than at the second only in ‘Banaćanka’ and ‘Slavica’. At the first harvest date, pod rupture force along the vertical axis was highest in ‘Banaćanka’ (1.56 N), and the force along the horizontal pod axis was greatest in ’Banaćanka’ (1.38 N), followed by ’Slavica’ (1.33 N). At the second harvest date, overripe plants showed no significant differences in pod rupture force values among the tested cultivars. Pod shatter force values were higher than rupture force values along the vertical and horizontal axes in all cultivars at both harvest dates in both Elastiq treatments. The foliar treatment with Elastiq to improve the mechanical properties of pods increased pod shatter resistance in all cultivars along both the horizontal and vertical pod axis. Also, Elastiq treatment improved pod rupture resistance along the horizontal axis in all cultivars, and along the vertical axis only in ’Banaćanka’. In addition to the mechanical properties of pods, rapeseed cultivars were evaluated for the physical properties of seeds at different seed moisture levels (6%, 11%, 16% and 21%). The physical properties (thousand-seed weight, seed volume, porosity, the static angle of repose, the dynamic angle of repose and the static seed friction coefficient) increased, while true density and bulk density of the seeds decreased with increasing seed moisture content. The tested cultivars differed in all physical properties, in both years, except true density, bulk density and porosity in 2015. ‘Jasna’ had the highest values for thousand-seed weight and seed volume in the first experimental year, and the lowest for porosity, bulk density and true density in both years. The highest static and dynamic angles of repose were determined in ‘Slavica’. At any seed moisture level, the coefficient of static friction was highest against plywood, followed by plastic sheet, aluminium, steel and galvanised steel sheet, and the lowest against stainless steel sheet. The static friction coefficient on all frictional surfaces and at all seed moisture levels was lower in ’Banaćanka’ than in ’Jasna’ and ’Slavica’.en
dc.formatapplication/pdf
dc.languagesr
dc.publisherУниверзитет у Крагујевцу, Агрономски факултет, Чачакsr
dc.relationinfo:eu-repo/grantAgreement/MESTD/Technological Development (TD or TR)/31051/RS//
dc.rightsopenAccessen
dc.sourceУниверзитет у Крагујевцуsr
dc.subjectuljana repicasr
dc.subjectrapeseeden
dc.subjectsadržaj vode u zrnusr
dc.subjectsortasr
dc.subjectmehaničke osobine ljuskisr
dc.subjectsila otvaranja i kršenja ljuskisr
dc.subjectfizičke osobine zrnasr
dc.subjectprimena Elastiq-asr
dc.subjectseed moisture contenten
dc.subjectcultivaren
dc.subjectmechanical properties of podsen
dc.subjectpod shattering forceen
dc.subjectpod rupture forceen
dc.subjectphysical properties of seedsen
dc.subjectElastiqen
dc.titleUticaj sorte i vremena berbe na osnovne fizičke i mehaničke osobine ploda i zrna uljane repicesr
dc.typedoctoralThesis
dc.rights.licenseBY-NC-ND
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/46404/disertacija.pdf
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/46405/Ranko_Koprivica_Agronomski.pdf


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