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Overwintering of oilseed rape cultivars
No full textBakalaureusetöö
Põllumajandussaaduste tootmise ja turustamise õppekavalKliimamuutuse tagajärjel on sagenenud ekstreemsete ilmastikuolude esinemine talve, mis mõjutab oluliselt taliviljade talvitumist. Talvekindlus on üks rapsi aretuseesmärkidest ning seejuures on oluline võrrelda erinevaid sorte samades tingimustes.
Bakalaureusetöö eesmärgiks oli uurida erinevate rapsisortide talvitumist. Uurimustöö põhineb 2024-2025 hooajal Lõuna-Eestisse rajatud põldkatsel, kus võrreldi 17 erinevat sorti. Hinnati taimiku biomassi ja juurekaela läbimõõtu sügisel ning kevadel. Viimane biomassi hindamine toimus pärast aprilli öökülmasid. Sügisel oli kõige suurem biomass ning juurekaela läbimõõt sortidel Bernstein, Maverick ja Herakles, kuid kevadeks olid sortidevahelised erinevused kadunud. Kõige paremini talusid kevadist öökülma sordid sordid Dominator, Janosh, Matrix cl, Duke ja Romeo ning kõige kehvemini Texas, Manhattan, Teflon ja Beatrix cl. Uuritud hooaja talvine ilmastik oli talvitumiseks soodne, mis tähendab, et suuremate järelduste jaoks on vaja katset korrata.Climate change has increased the occurrence of extreme weather event during the winter, which has negative impact on overwintering. Winter hardiness is one important breeding aim in oilseed rape breeding programs. However, it is important to compare the varieties in the same conditions.
The aim of the Bachelor thesis was to study the overwintering of different varieties. The thesis is based on field trial conducted in South-Estonia in 2024-2025 season, where 17 varieties were compared. Biomass and the diameter of root collar was measured in the fall and the biomass was measured again in the spring. The last sampling was done after the late frost in April. The highest biomass and thickest root collar was in varieties Bernstein, Maverick ja Herakles in the fall. By the early spring there were no difference among varieties. The best varieties that tolerated late frost were Dominator, Janosh, Matrix cl, Duke and Romeo and the most sensitive were Texas, Manhattan, Teflon and Beatrix cl. Since the conditions of the winter during studied period were relatively mild, then the comparison needs to be repeated to make stronger conclusions
Antibacterial and Antioxidative Activity and Polyphenolic Profile of Extracts of the Tea Plant (Camellia sinensis) and Yerba Mate (Ilex paraguariensis)
No full textLõputöö
Veterinaarmeditsiini õppekavalViimastel aastakümnetel on kasvanud huvi looduslike bioaktiivsete ühendite kasutamise vastu toiduainetes. Tee ja mate koostises leiduvad polüfenoolid võivad aidata kaasa toiduainete säilivusaja pikendamisele, pärssides mikroorganismide kasvu ja oksüdatiivseid protsesse. Lõputöö eesmärgiks oli määrata hiina teepõõsa (Camellia sinensis (L.) Kuntze) ja matepuu (Ilex paraguariensis A.St.-Hil.) lehtede vesi- ja etanooliekstraktide antioksüdantne ja antibakteriaalne aktiivsus ning polüfenoolide profiil. Samuti oli eesmärgiks võrrelda ekstrakte omavahel, et selgitada välja kõige efektiivsemad ekstraktid edasiseks kasutamiseks järgnevates tootekatsetes. Hiina teepõõsa lehtedest valmistatud matcha, musta ja rohelise tee lehtede pulbritest ning matepuu lehtede pulbrist valmistatud vesi- ja 30% etanooliekstraktides analüüsiti polüfenoolsete ühendite profiile ja polüfenoolide kogusisaldus (ingl total polyphenol content – TPC) määrati HPLC-DAD-MS abil. Summaarne antioksüdantne aktiivsus (ingl total antioxidant capacity – TAC) mõõdeti 2,2-difenüül-1-pikrüülhüdrasüül (ingl 2,2-diphenyl-1-picrylhydrazyl – DPPH) ja Folin-Ciocalteu meetodite abil. Puljongi mikrolahjenduse meetodil 96-süvendiga mikroplaatidel vastavalt EVS-EN ISO 20776-1:2020 juhistele, määrati tee ja mate ekstraktide minimaalsed inhibeerivad kontsentratsioonid (MIK) toiduainetööstuses toiduohutuse seisukohalt oluliste bakterite, Listeria monocytogenes’e, Staphylococcus aureus’e, Escherichia coli ja Campylobacter jejuni suhtes. Tee ja mate ekstraktides tuvastati kokku 28 polüfenoolset ühendit, mis kuulusid hüdroksübensoehapete, hüdroksükaneelhapete, flavanoolide, flavonoolide ja teepigmentide hulka. Mate ekstraktides domineerisid hüdroksükaneelhapped, kuid tee ekstraktides olid ülekaalus flavanoolid. Polüfenoolide kogusisaldus oli kõrgeim mate ja rohelise tee etanooliekstraktides. Antioksüdantne aktiivsus oli kõrgeim rohelise tee ja matcha tee etanooliekstraktides. Kõik ekstraktid omasid antibakteriaalset aktiivsust S. aureus’e vastu. Kõige efektiivsemad ekstraktid edasistes tootekatsetes kasutamiseks võiksid olla rohelise ja matcha tee etanooliekstraktid nende paremate antibakteriaalsete ja antioksüdantsete omaduste tõttu võrreldes teiste ekstraktidega. Tulemused näitavad, et tee ekstraktidel on potentsiaal olla looduslikeks alternatiivideks sünteetilistele lisaainetele toiduainetööstuses. Käesolev töö on seotud Eesti Maaülikooli säästvat arengut toetavate valdkondadega: tervislik ja ohutu toit ning maismaa ja vee ressursside jätkusuutlik kasutamine, samuti ÜRO SDG-ga nr 12: vastutustundlik tarbimine ja tootmine.Consumers are increasingly more interested in using plant-based additives in food products instead of synthetic ones. Polyphenols found in tea can help extend the shelf life of food products by inhibiting the microbial growth and oxidative processes. The main objectives of this thesis were to find the antioxidant and antibacterial activity of water and ethanol extracts from the leaves of the tea plant (Camellia sinensis (L.) Kuntze) and yerba mate (Ilex paraguariensis A.St.-Hil.), and to determine their polyphenolic profiles. Additionally, the aim was to compare the extracts of the tea plant and yerba mate to identify the most effective extracts for further use in subsequent product trials. The polyphenolic profile and total polyphenol content (TPC) in water and 30% ethanol extracts of matcha, black, and green tea leaf powders made from the leaves of the tea plant, and mate made from yerba mate were analyzed using HPLC-DAD-MS. The total antioxidant capacity (TAC) was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteu methods. The minimum inhibitory concentrations (MIC) of the extracts were determined against bacteria that are prominent in the food industry, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Campylobacter jejuni, using the broth microdilution method on 96-well microplates according to the guidelines of EVS-EN ISO 20776-1:2020. A total of 28 polyphenolic compounds including hydroxybenzoic acids, hydroxycinnamic acids, flavanols, flavonols, and tea pigments were identified in tea and mate extracts. Hydroxycinnamic acids dominated in mate extracts, while flavanols predominated in tea extracts. The total polyphenol content was highest in ethanol extracts of mate and green tea. Antioxidant activity was highest in ethanol extracts of green tea and matcha tea. All extracts showed antibacterial activity against S. aureus. The most effective extracts for further testing in food products could be ethanol extracts of green and matcha tea due to their superior antibacterial and antioxidant properties compared to other extracts. The results of this study show that tea extracts have a potential to be used as alternatives to synthetic additives in the food industry. This work is related to the Estonian University of Life Sciences areas supporting sustainable development: healthy and safe food and sustainable use of land and water resources, as well as UN SDG No. 12: responsible consumption and production
Constructive solution of battery swapping unit in service station for unmanned agricultural robot
No full textReceived: June 10th, 2024 ; Accepted: March 10th, 2025 ; Published: March 26th, 2025 ; Correspondence: [email protected] fully automated battery swapping unit is an essential part of unmanned agricultural robot service, ensuring the continuous operation of the robot by allowing the agricultural vehicle to replace its depleted battery with a fully charged one without human intervention, enabling it to continue its work cycle in the field. Thus, the battery swapping unit is part of service station systems, along with fertilizer filling, water supply, energy generation, and storage systems. This article describes a unique prototype of a battery swapping unit that safely replaces a depleted battery with a fully charged one in 223.5 seconds. The main role is played by the moving battery cart, which transports the battery between the charging and robot positions using a gripper equipped with an electric lock, attached to the actuator, and a V-belt transmission driven by an electric motor. The selection of the optimal rotation frequency of the motor is also discussed in this article
Lammaste heaolu võrdlev hindamine erinevates pidamissüsteemides
No full textA Thesis for applying for the degree of Doctor of Philosophy in Agricultural Sciences.Väitekiri filosoofiadoktori kraadi taotlemiseks põllumajanduse erialal.ABSTRACT. The welfare of animals in livestock production is of importance for the animals, the general public and the sustainability of animal agriculture. Ways of assessing welfare for sheep have been developed, but those available are complex, time-consuming and may not be appropriate for the different ways of keeping sheep, different sheep breeds and different climatic conditions. This doctoral thesis examines some welfare problems of sheep farming, including issues related to weather conditions, and devises and tests a simplified welfare evaluation system for sheep that is reliable, easy-to use and is focussed on actual problems. Findings include: Sheep prefer to be outside even in the winter, and even in the cool winters of Estonia, so we should allow sheep to have access to the outdoors, even in winter. In the summer, even in the relatively cool summers of northern Europe, sheep can suffer from heat stress. If sheep are at pasture during warm days they will use shade if it is available, and if they do not have access to shade they are more likely to suffer from the heat. So we should ensure that sheep have access to shade while at pasture. Sheep panting score was used to assess heat stress. This is a simple measure to observe and could be included in sheep welfare assessment protocols. The importance of different welfare indicators for sheep of different interest groups was investigated. In brief, farmers thought that body condition (too thin sheep) was the most important welfare indicator, whereas the general public thought that lameness was the most important. Female respondents thought that welfare issues were more significant than male respondents. A simplified protocol to assess the welfare of sheep was developed, using inputs from welfare scientists and from farmers themselves. This was demonstrated to be practical and easy to use. This could be used by welfare assessors but also by farmers to easily check the welfare of their own sheep themselves.LÜHIKOKKUVÕTE. Loomade heaolu loomakasvatuses on oluline nii loomadele, laiemale üldsusele kui ka loomakasvatuse jätkusuutlikkusele. Lammaste heaolu hindamise viise on arvukalt välja töötatud, kuid sageli on need keerulised, aeganõudvad ega pruugi sobida erinevate lammaste pidamisviiside, erinevate lambatõugude ja erinevate kliimatingimuste jaoks. Käesolevas doktoritöös vaadeldakse mõningaid lambakasvatuse heaoluprobleeme, sh ilmastikuoludega seotud küsimusi ning töötatakse välja ja testitakse lammaste heaolu hindamise lihtsustatud süsteemi, mis oleks usaldusväärne, hõlpsasti kasutatav ja konkreetsele probleemile keskenduv. Uurimistulemused: Lambad eelistavad viibida õues ka talvel ja ka Eesti jahedatel talvedel. Seega peaksime võimaldama lammastel ka talvel õues viibida. Suvel, isegi Põhja-Euroopa suhteliselt jahedatel suvedel, võivad lambad kannatada kuumastressi all. Kui lambad on soojadel päevadel karjamaal, otsivad nad päikesepaiste eest varju, kui see on saadaval. Kui neil pole varjumisvõimalust, kannatavad lambad suurema tõenäosusega kuumuse käes. Seega peaksime tagama, et lammastel oleks karjamaal juurdepääs varjule. Kuumastressi hindamiseks määrati lammastel hingeldusskoor. Seda on lihtne määrata ja selle võiks lisada lammaste heaolu hindamise protokollidesse. Uuriti erinevate lammaste heaolunäitajate olulisust erinevate huvirühmade suhtumisele heaolu mõjutavatesse teguritesse. Lühidalt öeldes pidasid farmerid kõige olulisemaks heaolunäitajaks lammaste toitumust (lahjunud lambad), laiem avalikkus aga longete esinemist lammastel. Naissoost vastajad võrreldes meesvastajatega pidasid heaoluküsimusi olulisemaks. Töötati välja teadlaste ja farmerite poolt välja pakutud näitajate alusel lihtsustatud lammaste heaolu hindamise protokoll, mida on praktiline ja lihtne kasutada. Seda võiksid kasutada lammaste heaolu hindajad, aga ka loomaomanikud, et ise hõlpsasti oma lammaste heaolu kontrollida
Väinjärv
No full textPhytoplankton biomass, diversity and abundance in samples collected from Lake Väínjärv during the period 1954-2015
Oocyte recovery and maturation rates in Estonian Sport Horses : [presentation]
No full textOvum pick-up (OPU) and intracytoplasmic sperm injection (ICSI) are rapidly gaining interest in the horse industry. The ability to preserve the genetics, efficiently use scarce or expensive semen, and produce embryos out of the breeding season from competing mares has proven attractive to sport horse breeders. Recently, our research group introduced the commercial equine in vitro embryo production system in Estonia, achieving the first commercial ICSI pregnancy. The Estonian Sport Horse breed is a mix of European warmbloods whose success in show jumping and dressage disciplines has gained international interest. Breed has been shown to significantly affect
the efficiency of an OPU-ICSI program (Fonte et al. 2024 Theriogenology 223, 47–52). Thus, the aim of our study was to to evaluate the effect of the seasonality on oocyte recovery rates and the effect of different oocyte holding media on maturation rates in ESH.This study was supported by the EU through the European Regional Development Fund, grant nr 616221790109
Diminished work ability as a contributing factor for farmer’s interest in switching to organic production
No full textReceived: January 31st, 2024 ; Accepted: April 11th, 2025 ; Published: April 14th, 2025 ; Correspondence: [email protected] studies suggest organic producers have diminished work ability, but it is unclear if this is due to pre-existing conditions or work exposures in organic production itself. The current study explored whether diminished work ability is a contributing factor to the interest in switching from conventional to organic production. The study used data from 2018, Finnish farmer questionnaire, analysed by machine learning - based approach and logistic regression modelling. Nearly half (46%) of the survey respondents (n = 2,948) had a diminished work ability score. Seventeen percent (n = 501) of the respondents reported being interested in switching to organic production. Farmers with diminished work ability had greater odds (OR 1.56, 95% CI: 1.26–1.92) for showing interest in switching. Those growing horticulture and special crops (vs. cereals) (OR 0.55) and those age 55+ years (vs. less than 35) (OR 0.51) showed less interest in switching. The interest in starting or expanding organic production was higher among those who already had an organic agreement on part of their farm (OR 5.7) and those who had other business activities on the farm (OR 1.36). In summary, this study suggests that diminished work ability predicts farmer’s interest for switching to organic production. Measures to protect the health and well-being of farmers and workers during and after switching to organic production is critically important in achieving not only policy goals to increase organic production, but also good quality of life of farmers
Viitna Linajärv
No full textPhytoplankton biomass, diversity and abundance in samples collected from Viitna Linajärv during the period 1932-2003
In Memoriam. Rektor emeritus, president Arnold Rüütel (10.05.1928 - 31.12.2024)
No full textEesti Maaülikooli mälestusraamat sisaldab järelhüüdeid president Arnold Rüütlile
Arbi
No full textPhytoplankton biomass, diversity and abundance in samples collected from Lake Arbi during the period 1975-1996