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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Žieminių kviečių spelta agrofitocenozės pokyčių dinamika šiltėjančio klimato sąlygomis / Spelta winter wheat agrophytocenosis changes dynamics at changing climate conditions

Gudauskienė, Aušra 13 June 2012 (has links)
Magistrantūros studijų baigiamajame darbe pateikiami tyrimų duomenys apie piktžolių dygimą, sunykimą ir bendrą jų skaičių žieminių kviečių spelta pasėlyje nuo sėjos iki derliaus nuėmimo. Apie žieminių spelta kviečių piktžolėtumą, piktžolių sausųjų medžiagų masę g m‾², jų rūšinę sudėtį ir dirvos piktžolių sėklų banką 0-10 ir 10-20 cm armens sluoksnyje: Darbo objektas –žieminių kviečių spelta veislės 'Franckenkorn' agrofitocenozės piktžolėtumo dinamika kintančio klimato sąlygomis, sėjos laiko fonuose. Darbo metodai: Piktžolių dygimo ir sunykimo dinamika spelta žieminiuose kviečiuose nustatyta visuose laukeliuose, atsitiktine tvarka įrengus po 3 pastovias piktžolių išdygimo ir sunykimo stebėjimų aikšteles (viso 24 stacionarios piktžolių apskaitos aikštelės). Piktžolėtumo vertinimas nustatytas kiekiniu svoriniu metodu. Piktžolės buvo suskirstytos į rūšis pagal biologinę- agronominę klasifikaciją (Montsvilaitė, 1996). Darbo rezultatai. Piktžolių sudygimas, sunykimas ir bendras jų skaičius esmingai priklausė nuo eksperimento tiriamųjų veiksnių – spelta žieminių kviečių sėjos laiko, piktžolėtumo apskaitos laiko ir jų sąveikos. Vėlyvesnės sėjos pasėlyje nustatytas intensyvesnis piktžolių sudygimas, galimai dėl vėlyvesnio kviečių sudygimo ir lėtesnio pasėlio vystymosi. Tik gegužės mėnesį intensyvėjant piktžolių sudygimui, ankstyvesnės sėjos pasėlyje nustatyta piktžolių sudygimo didėjimo tendencija lyginant su vėlyvesnės sėjos pasėliu. Piktžolių sunykimas nustatytas tik sausio – kovo... [toliau žr. visą tekstą] / Master's thesis presented research data on the germination of weed, the decline and the total number of winter wheat spelta crop from sowing to harvesting. The weediness of winter wheat spelta, weed dry weight g m -², their species composition and soil weed seed bank of 0-10 and 10-20 cm soil layer: Object of the work – weediness dynamics of the winter wheat spelta 'Franckenkorn' agrophytocenoses of different sowing time in a changing climate conditions. Method of the work weed germination and death dynamics of the winter wheat spelta in arranged stacionary plots (total 24 stacionary observation plot side). Assessment of the weed quantitatively weighted method. Crop weedines were assesedby the quantitative-weighing method. Weeds were grouped according to the biologic-agronomic classification of weeds (Mostvilaitė, 1996). The results of work. Weed germination, death and the total number essentialy depende on the experimental factors - winter wheat spelta sowing time, weed ccounting time and interaction of the factors. The more intensive crop weed germination was established in the latersowe drop, possibly due to later wheat germination and slower crop development. In earlier sowed winter wheat spelta crop only in May with increase of weed germination was established intensivification of weed germination comparing it with the crop of later sowing time. Decline of weed number was found in January - March. The higher total weediness of the winter wheat spelta crop was... [to full text]
2

Vyhodnocení efektu vláčení na zaplevelenost, výnosové parametry a jakost pšenice špaldy. / Influence of harrowing of wheat on weeds rate, yield parameters and quality of spelt.

BERÁNEK, Jaroslav January 2019 (has links)
The diploma thesis deals with harrowing of spelt wheat (Triticum spelta L.) by the weeding harrows and its influence on weed frequency, yield and quality parameters of wheat. In the literature review there are described general cultivation principles for the growing of spelt (Triticum spelta L.) used in current agricultural practice. There is overview of the general principles of spelt wheat cultivation in the organic farming, available varieties in the Czech Republic and brief description of agricultural technology suitable for its cultivation. We also describe the types of weeds, their brief description and the possibility of reducing their frequency in the organic farming growing system. The literature review provides also information about the technology of harrowing cereal crops as a measure to control weeds and other positive aspects of harrowing on grain crops. In the practical part, data from a field trial were collected, where the effect of harrowing on the weed frequency, the influence of harrowing on spelt wheat tillering and other parameters were statistically evaluated and compared with results in the literature. At the end of the thesis, given the results evaluated in the practical part, it was determined whether it is appropriate to use harrowing as protection of spelt wheat (Triticum spelta L.), its number, influence on weed infestation and its influence on both the quantitative and qualitative properties of spelt wheat (Triticum spelta L.).
3

Identifikacija Alternaria spp. na zrnu spelte i uticaj zaraze na komponenete prinosa, sadržaj mikotoksina i tehnološki kvalitet / Identification of Alternaria spp. on spelt kerenels and impact of infection on yield parameters, mycotoxins content and technological quality

Đisalov Jovana 11 December 2015 (has links)
<p>Savremeni trendovi na trži&scaron;tu utiču na sve veću potražnju za speltom (Triticum aestivum ssp. spelta), alternativnom, plevičastom formom p&scaron;enice visoke nutritivne vrednosti, koja doprinosi održavanju agroekolo&scaron;kih sistema gajenja. Smatra se da prisustvo plevičastih omotača pruža za&scaron;titu zrna od različitih bolesti i &scaron;tetočina, &scaron;to je od naročitog značaja za organsku proizvodnju gde upotreba hemijske za&scaron;tite nije dozvoljena. Rod Alternaria obuhvata veliki broj izrazito varijabilnih i &scaron;iroko rasprostranjenih saprofitnih i fitopatogenih vrsta. Značaj Alternaria spp. se ogleda ne samo u smanjenju prinosa i naru&scaron;avanju kvaliteta zrna p&scaron;enice, već i u tome &scaron;to mnoge vrste ovog roda produkuju toksične metabolite, koji su &scaron;tetni za zdravlje ljudi i životinja. U cilju preduzimanja blagovremenih i efikasnih mera suzbijanja fitopatogenih vrsta roda Alternaria i monitoringa dominantnih toksigenih vrsta, veoma je značajna njihova pouzdana i prezicna identifikacija.<br />Istraživanja su obuhvatila identifikaciju i molekularnu karakterizaciju Alternaria spp. na zrnu spelte u Republici Srbiji uz analizu intenziteta zaraze posebno plevičastih i olju&scaron;tenih zrna spelte kako bi se ispitala efikasnost plavičastih omotača u za&scaron;titi zrna spelte. Istovremeno je određen sadržaj najznačajnijih Alternaria toksina (alternariol-AOH i alternariol monometil-etar-AME), kao i sveobuhvatni uticaj ovih gljiva na komponente prinosa, zdravstvenu bezbednost i tehnolo&scaron;ki kvalitet spelte. Izolovano je ukupno 25 Alternaria spp. sa zrna spelte roda 2011. god. iz različitih regiona Vojvodine i na osnovu morfolo&scaron;kih, patogenih i molekularnih karakteristika utvrđeno je prisustvo dve vrste: A. tenuissima (22 izolata) i A. infectoria (3 izolata). Dobijeni rezultati predstavljaju ujedno i prvo naučno saop&scaron;tenje od vrstama roda Alternaria na spelti u Srbiji. Ve&scaron;tačkom inokulacijom tri različita genotipa spelte (Nirvana, Austria i Ostro) odabranim Alternaria izolatima u 2011. i 2012. god. uočena je značajna razlika u intenzitetu zaraze Alternaria spp. na zrnima sa plevičastim omotačima gde se intenzitet infekcije kretao od 87-100% dok je na olju&scaron;tenim zrnima iznosio od 16-72% u 2011. god., odnosno od 95-100% na plevičastim zrnima i 42-68% na olju&scaron;tenim zrnima u 2012. god. Efekat hemijske za&scaron;tite fungicidom se pokazao značajan za redukciju Alternaria spp. u obe istraživačke godine kako na plevičastim tako i na olju&scaron;tenim zrnima spelte. Kolorimetrijskim merenjima intenziteta zaraze plevičastih omotača i olju&scaron;tenih zrna inokulisanih biljaka u 2011. i 2012. god. potvrđena su standardna vizuelna fitopatolo&scaron;ka ispitivanja, &scaron;to ukazuje na to da se metoda instrumentale ocene zaraze može koristiti kao efikasna i brza metoda detekcije tamnokličnih zrna, gde uz dodatne verifikacije postoji mogućnost primene i u praksi. AOH i AME detektovani su u proseku četiri puta većoj koncentraciji u plevičastim omotačima nego u olju&scaron;tenim zrnima, &scaron;to potvđuje efikasnost plevičastih omotača u za&scaron;titi zrna spelte, ne samo od prodiranja Alternaria spp. već i od njihovih toksičnih metabolita. Najmanja koncentracija Alternaria toksina zabeležena je na olju&scaron;tenim zrnima bijaka tretiranih fungcidom (AOH - 84 &mu;g/kg i AME - 153 &mu;g/kg). Ispitivanja prometnog i tehnolo&scaron;kog kvaliteta spelte zaražene Alternaria spp. su pokazala da tamnoklična zrna značajno naru&scaron;avaju parametre prometnog i tehnolo&scaron;kog kvaliteta spelte, negativno utičući na nalivanje i sazrevanje zrna kao i sintezu skroba i proteina.<br />Prikazani rezultati ukazuju na to da plevičasti omotači predstavljaju efikasnu barijeru u za&scaron;titi zrna od infekcije vrstama roda Alternaria, &scaron;to ima izuzetan značaj za otpornost spelte naročito u uslovima gajenja u sistemu organske proizvodnje gde upotreba hemijske za&scaron;tite nije dozvoljena. Međutim, uprkos prirodnoj otpornosti i genetskoj predodređenosti spelte za organsku proizvodnju, rezultati efikasne primene fungicida u suzbijanju Alternaria spp. opravdavaju adekvatan hemijski tretman u dobroj poljoprivrednoj praksi i proizvodnji zdravstveno bezbedne hrane. Multidisciplinarni pristup ove doktorske disertacije, ukazuje na neophodnost komplementarnog sagledavanja agronomskih i tehnolo&scaron;kih aspekata u poljoprivrednoj i prehrambenoj industriji, kao jedinstvenog modela koji omogućava praćenje savremenih tendencija u proizvodnji zdravstveno bezbedne hrane visokog nutritivnog kvaliteta.</p> / <p>There is an increasing market demand for alternative crops such as spelt wheat (Triticum aestivum ssp. spelta), an ancient, hulled with high nutritional values which<br />6<br />encourages agroecogical production systems. Accodrding to literture overview, it is considered that hulls protect kernels aginst different pests and pathogens, which is of great importance in organic production where chemical treatment is forbidden. Alternaria is a ubiquitous fungal genus that includes saprobic, and pathogenic species associated with yield losses and reduction of technological quality of small grains. Moreover, some of Alternaria spp. has high toxigenic potential and can be harmful for human and animal health. In order to conduct efficient disease control and monitoring of toxigenic Alternaria species, precise and reliable identification is highly important issue.<br />This study include identification and molecular characterisation of Alternaria spp. isolated from spelt kernels in the Republic of Serbia, followed by assessing of level of infection of hulled and dehulled kernels, separately. Additionally, the content of the most important Alternaria toxins (alternariol-AOH and alternariol monomethyl-etar-AME) is analysed, as well as the overall impact of infection on yield parameneters, food safety and technological quality of spelt wheat. Out of 25 Alternaria strains isolated from spelte kernels harvested in 2011. from different regions of Vojvodina and according to morphological, pathogenic and molecular characteristics, the most dominant species was A. tenuissima (22 isolates) followed by A. infectoria (3 isolates). This is the first report of Alternaria spp. detected on species level on spelt wheat in Serbia. After artificial inoculation of three different spelt genotypes (Nirvana, Austria i Ostro) with Alternaria isolates in 2011. and 2012., the sighnificant difference in the level of infection on hulled and dehulled kernels is noted. On the hulled kernels infection was in the range of 87-100%, while on the dehulled kernels was from 16 to 72% in 2011., and from 95 to 100% on hulled kernels and from 42 to 68% on dehulled kernels in 2012., respectivelly. Chemical treatment showed positive effect in the reduction of Alternaria disease in both years, on hulled and dehuled kernels as well. Colorimetric measurements of the level of infection proved conventional phytopatholoical analyses, which indicates that such instrumental method can be efficiently used in rapid detection of black point kernels and with additional verifications might be use in practise. AOH and AME were detected in four time higher concetrations in hulls compared to dehulled kernels, which confirms that hulls act as barriers against fungal infection and their toxic metabolities. The minimum concetration was detected on dehulled kernels treated with fungicide (AOH - 84 &mu;g/kg i AME - 153 &mu;g/kg). In the technological quality analysis of infected kernels, it was found that black point disease reduced tecnhnological quality, due to negeative impact of infection on maturation of grains and sinthesis of proteins and starch.<br />Presented results indicate that hulls on spelt kernels act as efficient barrires in the protection of kernels against Alternaria spp. and their toxic metabolities, which is of great importance for the resistance of spelt wheat particulary in the organic farming where chemical treatment is forbidden. Inspite of the fact that spelt is suitable for organic production, adequate fungicide application against Alternaria spp. is justified from the aspect of the good agriculture practise and food safety. Multidisciplinary approach of this doctoral dissertation points to necessity of complementary perception of agronomic and technological aspects in agriculture and food industry, as the unique model that supports contemporary trends in the production of food safety products with high nutritional value.</p>
4

Optimizacija procesa ekstrudiranja spelte za kreiranje funkcionalnih proizvoda sa dodatkom betaina / Optimization of the extrusion process in creation of snack products from spelt wholegrain flour with added betaine

Kojić Jovana 15 September 2018 (has links)
<p style="text-align: justify;">Betain je bioaktivno jedinjenje, koje ima značajne fiziolo&scaron;ke funkcije u čovekovom organizmu kao osmolit i donor metil grupa za mnoge biohemijske procese. Endogena sinteza betaina je uglavnom nedovoljna da zadovolji potrebe organizma te je zbog toga neophodan njegov unos preko hrane. Žitarice predstavljaju glavni izvor betaina u ljudskoj ishrani. Jedan od načina da se poveća unos betaina u ljudskoj ishrani je preko funkcionalne hrane obogaćene betainom. Prema regulativi evropskog udruženja cerealija za doručak (European Breakfast Cereal Association) iz 2012. god. (Commission Regulation (EU) No 432/2012) dozvoljeno je deklarisanje zdravstvene izjave za prehrambene proizvode koji sadrže najmanje 500 mg betaina po porciji (40g flips proizvoda) uz navođenje napomene da se zdravstveni efekti mogu očekivati ukoliko se dnevno unese 1500 mg betaina. Zdravstvena izjava glasi: &bdquo;betain doprinosi normalnom metabolizmu homocisteina&ldquo;. Povećano interesovanje za zdravu ishranu dovelo je do veće potražnje za alternativnim žitaricama, gde spelta zbog svojih biolo&scaron;kih, agronomskih, prehrambenih i medicinskih karakteristika kao i bogatih nutritivnih svojstava, zauzima značajno mesto. Glavni cilj ove teze je bila optimizacija ekstrudiranja i proizvodnje funkcionalnog flips proizvoda od speltinog integralnog bra&scaron;na sa dodatkom betaina na dvopužnom ekstruderu. Prvi put je u procesu prehrambenog ekstrudiranja primenjena analiza vi&scaron;eciljne optimizacije u kombinaciji sa neuronskim mrežama i genetskim algoritmom kako bi se dobio maksimalan sadržaj betaina u flips proizvodu pri minimalnoj potro&scaron;nji specifične mehaničke energije. Definisan je nov funkcionalni proizvod sa betainom koji bi potencijalno pro&scaron;irio asortiman flips proizvoda na trži&scaron;tu i utvrđene su njegove fizičke, funkcionalne, teksturalne, reolo&scaron;ke i senzorske osobine. Sadržaj betaina i potro&scaron;nja specifične mehaničke energije su ključni izlazi koji predstavljaju konkurentne ciljeve u procesu ekstrudiranja. Za proizvodnju flips proizvoda pobolj&scaron;anog nutritivnog kvaliteta i funkcionalnog profila koji sadrži od 1601,6 do 1764,7 mg betaina u 40 g (čime se i zadovoljava preporučeni dnevni unos betaina) i kome odgovara potro&scaron;nja specifične mehaničke energije od 97,4 do 114,1 Wh/kg optimalni su sledeći procesni parametri: protok materijala od 20,45 do 24,04 kg/h, vlaga materijala od 18,6 do 19,44 % i brzina obrtanja pužnice od 250 obrtaja u minuti. Da bi se dobili pouzdani rezultati za sadržaj betaina u spelti i flips proizvodima razvijena je, optimizovana i validovana metoda tečne hromatografije visokih perfomansi. Metoda je uspe&scaron;no primenjena i u analizi betaina u žitaricama, pseudožitaricama i njihovim proizvodima.</p> / <p>Betaine is a bioactive compound that has significant physiological functions in the human organism as an osmolite and methyl group donor for many biochemical processes. The endogenous synthesis of betaine is generally insufficient to satisfy the requirements of the organism, therefore its intake is necessary through the food. Cereals are the main sources of betaine in human nutrition. One of the ways to increase betaine intake in human nutrition is through betaine enriched functional foods. In the 2012 European Union Regulation (Commission Regulation (EU) No 432/2012), it is permissible to declare a health statement for foods containing at least 500 mg betaine per portion (40g of extruded product), stating that the health effects can be expected if 1500 mg of betaine are consumed on a daily basis. The health statement states: &quot;Betaine contributes to the normal metabolism of homocysteine.&quot; Increased interest in healthy food has led to the higher demand for alternative cereals, where spelt takes a significant place due to its biological, agronomic, nutritional and medical characteristics, as well as its rich nutritional properties. The main goal of this work was the optimization of extrusion and production of the functional snack product from spelt wholegrain flour with the addition of betaine which is performed on twin-screw extruder. According to our best knowledge, there was no investigation in which the multi-objective optimization (MOO) analysis coupled with artificial neural network and genetic algorithm was applied to the extrusion cooking process in order to achieve simultaneously maximum betaine content and minimum energy consumption in the snack spelt product. A new functional snack product that can potentially expand the range of snack products and its physical, functional, textural, sensory and rheological properties were defined. The betaine content and specific mechanic energy are the key outputs that represent competing objectives in the extrusion proces. To produce snack product with improved nutritive quality and functional profile which contains betaine content from 1601,6 to 1764,7 mg/40g, which would contribute to the recommended daily intake of betaine, correspond to specific mechanical energy from 97,4 to 114,1 Wh/kg, following optimal parameters were obtained: feed rate from 20,45 to 24,04 kg/h, moisture content from 18,6 to 19,44 % and screw speed at 250 rpm. Also, optimization, development and validation of the high pressure liquid chromatographic method for measuring betaine content in spelt and snack products was also designed and applied.</p>
5

Možnosti identifikace pšenice špaldy pomocí mikroskopických a molekulárních metod

Vlašínová, Martina January 2017 (has links)
Common wheat and spelled wheat are one of the most important agricultural crops. Their use is mainly in the food industry and also in the feed industry. There is a strong interest in the differentiation of the common wheat from the spelled wheat in the last tens of years. This trend is especially in the food industry because of the adulteration of the spelled flour. This dissertation was focused on the differentiation of the common wheat from the spelled wheat by using the microscopic methods and on the detection of variability in the gene for gamma wheat gliadin by the molecular markers (RFLP method). Through the molecular analysis of the 15 tested varieties of the spelled wheat and one variety of the common wheat were obtained the results which make us able to detect the proportion of the spelled wheat in the common wheat.
6

Wheat taxonomy and cultivar identification using molecular markers

Cao, Wenguang 01 January 1997 (has links)
Molecular markers were used in an attempt to determine the phylogenetic relationships of hexaploid wheats within Triticum aestivum L. and to identify wheat cultivars. Random amplified polymorphic DNA (RAPD), restriction fragment length polymorphism (RFLP), gliadin protein and cytological analyses were used to assess phylogenetic relationships among five morphological groups of hexaploid wheat, namely, macha, common wheat, spelta, vavilovii and semi-wild wheat (SWW). RAPD and gliadin data were analysed using the NTSYS-pc computer program to generate Jaccard genetic similarity coefficients. Coefficients of genetic similarity in the cytological study were calculated based on the number of chiasmata in hybrids. Dendrograms were constructed based on these coefficients. The dendrogram based on RAPD analysis grouped 15 accessions into five distinct clusters which were in agreement with the morphology-based classification. The results indicated that common wheat was closely related to vavilovii. Spelta was less related to the common and vavilovii wheat cluster. SWW was distantly related to common wheat. Macha was the least related to the previous clusters. These results were consistent with those based on cytological analysis. The results of gliadin analysis were not completely consistent with those based on RAPD and cytological analyses. RFLP data showed that it was difficult to determine phylogenetic relationships among the five groups of hexaploid wheat based on variation in the intergenic spacer region of the 18-25S rRNA unit. Polymerase chain reaction analysis of the 5S rRNA unit and the internal transcribed spacer of the 18-25S rRNA unit did not show any polymorphism among and within the five groups of hexaploid wheat. Twelve mis-classified Triticum accessions were found in macha and vavilovii wheat collections and investigated using RAPD and cytological analyses. A dendrogram based on RAPD analysis classified the 12 accessions into either T. monococcum, T. turgidum spp. dicoccum or T. timopheevii. The results were in agreement with cytogenetic data and morphological observations. The genetic diversity of spelta and macha wheat was also investigated using RAPD analysis and the results were generally consistent with geographic origins. Macha wheat germplasm was found slightly more diverse than spelta wheat although macha has a restricted geographic origin. In addition, duplicate accessions of macha and spelta were identified based on RAPD analysis. In the study of wheat cultivar identification and pedigree assessment, 29 cultivars were investigated using RAPD analysis. Cultivar specific markers were found, and at least eight cultivars could be identified using these specific markers. Cultivar relationships based on genetic similarity values were consistent with knownpedigrees. The study demonstrated that RAPD analysis can be used for estimating the phylogenetic relationships among the five groups of hexaploid wheat, reclassifying misclassified wheat germplasm, surveying the genetic diversity of spelta and macha wheat and identifying common wheat cultivars and duplicated accessions in wheat germplasm collections.

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