2023, Vol. 21, No. 2

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/8781

Sirvi

Nüüd näidatakse 1 - 20 28

Performance evaluation and variability analysis for morpho-physiological traits of orange fleshed tomato varieties introduced in Nigeria climatic conditions
(Estonian University of Life Sciences, 2023) Esan, V.I.; Sangoyomi, T.E.; Ajayi, O.A.; Christensen, M.; Ogunwole, J.O.
The introduction of orange flesh tomato in Nigeria climatic conditions through characterization is the best way to understand its adaptability and fight against the lack of ß-carotene in the landraces and improved varieties currently cultivated in the country. This study was aimed to evaluate7 tomato varieties comprised of 4orange-fleshed tomato imported from New Zealand and 3 local varieties for their morphological, agronomic and chemical composition and fruit quality characters. Phenotyping was used to assess the morphological and agronomic traits and while biochemical assays was used for fruit quality characters. The four orange fleshed tomato varieties were indeterminate and the 3 local varieties were determinate. There were significant variability and differences in plant height (54.93 cm to 72.23 cm), leaf number (14 to 24), leaf length (24.10 cm to 28.53 cm), length width (15.13 cm to 16.93 cm), internode length (2.41 cm to 3.29 cm), root collar (3.46 cm to 4.53 cm), days to 1% flowering (20 to 23), days to maturity (34 to 42), number of clusters per plant (5 to 10), fruits per cluster (4 to 6), fruit weight (72.64 g to 488.58 g), fruit length (27 mm to54.89 mm), fruit diameter (23.67 mm to 28 mm), transverse fruit section (1 mm to 3 mm), moisture content (92.30 to 95.33%), protein (0.15 to 1.02%), fat (0.15 to 1.02%), fibre (0.92 to 2.37%) and carbohydrate (1.86 to 6.41%). At the time the local varieties senesced they showed higher yields than the introduced varieties, but as indeterminate they were better than the local ones because they continued fruiting after the local ones died off. Flesh color of pericarps and ripened fruit color ranged from orange to red while fruit shape varied from highly rounded to cylindrical (long oblong). Fruit size showed variation from small to moderate size.
The influence of nitrogen fertilization and legume species on the productivity of multi-species swards in four production years
(Estonian University of Life Sciences, 2023) Adamovics, A.; Gutmane, I.
The aim of current research was to investigate forage yield and crude protein content of legume-grass mixtures during four years of sward use, applying three nitrogen (N) fertilisation rates: N0, N60, and N120. Three perennial legume species - red clover Trifolium pratense (Tp), lucerne Medicago sativa (Ms) and fodder galega Galega orientalis (Go) were tested in mixtures with grasses (G). Mixtures were composed of 50% of legumes and 50% of grasses. Lucerne and fodder galega are introduced forage legume species in Latvia, and are raising an ever-growing interest in Latvia. The studies of persistency, quality and yielding ability of these legume species in Latvian agroclimatic condition in comparison with traditionally used red clover are actual. Significant differences in dry matter (DM) yields were found between successive production years, mixtures, and N fertilization rates. The highest average DM yield was found for the mixture with lucerne (Ms+G). The decline in productivity between the first and fourth production years was more expressed for red clover mixture, but a more stable productivity was demonstrated by swards with galega (Go+G). The N rate increase contributed to a significant DM yield increase for all mixtures. The positive effect of the increased N rates on DM yield increase was better expressed for red clover mixture (Tp+G). Red clover mixture (Tp+G) had the lowest average crude protein (CP) content. Mixture with galega had a higher CP content in the third and fourth production years. The CP content of red clover mixtures increased by nitrogen rate.
Application of UAV multispectral imaging for determining the characteristics of maize vegetation
(Estonian University of Life Sciences, 2023) Änäkkälä, M.; Lehtilä, A.; Mäkelä, P.S.A.; Lajunen, A.
Interest in forage maize (Zea mays L.) cultivation for livestock feed has grown in northern conditions. In addition, it is important to develop methods and tools to monitor crop development and other characteristics of the crop. For these purposes UAVs are very efficient and versatile tools. UAVs can be equipped with a variety of sensors like lidar or different types of cameras. Several studies have been conducted where data collected by UAVs are used to estimate different crop properties like yield and biomass. In this research, a forage maize field experiment was studied to examine how well the aerial multispectral data correlated with the different properties of the vegetation. The field test site is located in Helsinki, Finland. A multispectral camera (MicaSense Rededge 3) was used to take images from five spectral bands (Red, Green, Blue, Rededge and NIR). All the images were processed with Pix4D software to generate orthomosaic images. Several vegetation indices were calculated from the five spectral bands. During the growing season, crop height, chlorophyll content, leaf area index (LAI), fresh and dry matter biomass were measured from the vegetation. From the five spectral bands, Rededge had the highest correlation with fresh biomass (R2 = 0.273). The highest correlation for a vegetation index was found between NDRE and chlorophyll content (R2 = 0.809). A multiple linear regression (MLR) model using selected spectral bands and vegetation indices as inputs showed high correlations with the field measurements.
Technological properties of wheat flour with additives
(Estonian University of Life Sciences, 2023) Kostetska, K.; Ulianych, O.; Shevchuk, K.
The research was carried out on the possibility of using potherbs in bakery industry. Powder of plants were used to replace 0.5%, 2%, 5%, 10% and 15% of wheat flour: Chenopōdium quīnoa L.; Cyperus esculentus L.; Physalis tomentous L.; Cosmos sulphureus Cav.; Pycnanthemum virginianum L.; Pycnanthemum trifolium L.; Agastache rugosa (Fisch. & C.A. Mey.) Kuntze; Agastache urticifolia (Benth.) Kuntze, cv. Weide Kerze; Mentha spicаta L. ‘Moroccan’; Achillea setacea Waldst. Et Kit.; Isodon japonicus var. Glaucocalyx (Maxim.) H. W. Li; Satureja montana L.; Teucrium scorodonia L.; Ruta montana L.; Népeta argolica Bory et Chaub.; Népeta grandiflora L.; Népeta mussinii Spreng. Ex Henckel., cv. Posviata Meisu; Népeta nepetelia L. In order to develop an effective technology for its use, creating new types of products with properties that meet current needs of consumers in Ukraine and the world, it is necessary to clarify the relation of potherbs with other components. Baking properties determine the behavior of flour in technological process, namely, they form the quality of bread and depend on the state of carbohydrate-amylase, protein-proteinase, lipidlipolytic complexes, as well as the content of compounds that cause darkening of flour during the process of bread making. Use of herbs in bakery is promising. The data obtained allows manufacturers to recommend the use of herbs during the production of bread.
Parametric and nonparametric stability of grain yield and grain protein content in durum wheat genotypes with various origins
(Estonian University of Life Sciences, 2023) Dragov, R.; Taneva, K.; Bozhanova, V.
Identification of genotypes that can maintain a good yield and quality performance under climatic variability is critical for ensuring future food security. The aim of this study was to determine the stability of fifty-four durum wheat varieties with different geographical origins conceming the traits grain yield and grain protein content by parametric and nonparametric assessments. The varieties were tested in three consecutive years 2019–2021 in a randomized block design in three replications. Four nonparametric stability assessment, four parametric stability assessment, the coefficient of variation and the simulated assessment of yield and stability by Kang were determined. The analysis of variance revealed a significant influence of genotypes, environment and the genotype and environment interaction (GxE) on the expression of both studied traits. The environment showed a greatest influence on the variation of both traits. Eleven genotypes achieved average yield above 6.00 t ha-1 . The genotypes with a high average yield and grain protein content and high stability as determined by the most stability assessments were identified as Melina (BG), Raylidur (BG) and Beloslava (BG) - for grain yield and varieties as Cesare and Beloslava (BG) - for grain protein content. The Bulgarian variety Beloslava was the most valuable combination high yield and grain protein content along with high stability for both traits across different seasons. Beloslava can be recommended for involvement in durum wheat breeding programs for simultaneously improvement of productivity and grain quality and to develop new durum wheat varieties well adapted to changing climate conditions.
Methanol-HVO blends for efficient low-temperature combustion: analytical research on fuel properties
(Estonian University of Life Sciences, 2023) Wang-Alho, H.; Sirviö, K.; Hissa, M.; Mikulski, M.; Niemi, S.
Next-generation low-temperature combustion (LTC) engines can accommodate ultra-high efficiency with near-zero NOx and PM emissions. Reaction kinetics is the governing mechanism in LTC. Onboard fuel reactivity control is, thus, becoming an interesting concept that ultimately provides pathways toward a fully fuel-flexible engine. No matter the technical realisation - in-cylinder blending or pre-blending/emulsification - the reactivity control requires fuels with complementary properties. Methanol and hydrotreated vegetable oil (HVO) seem to be one of the most promising, yet under-studied combination for LTC engines. They are both renewable and can be mixed together. Methanol’s high knock resistance and large latent heat of evaporation enable a wide engine load range, with a propensity to reduce NOx emissions and mitigate thermal or mechanical stress. The same properties on the other hand require highly reactive fuel to enable the mixture to self-ignite controllably in LTC conditions. HVO is amongst the most reactive renewable alternatives and its clean paraffinic structure further mitigates particle matter formation. - Importantly, in pre-blending HVO emulsification can resolve the lubricity issues of methanol. In this paper, the aim was to study the engine-relevant properties of HVO-methanol fuel blends. The analysed properties were the distillation properties, density, kinematic viscosity, cetane index, and flash point. Based on the results, the suitability of the chosen blend shares for LTC concepts was evaluated.
Obtaining compostable composites from secondary raw materials of crop production
(Estonian University of Life Sciences, 2023) Nikolaev, E.; Molodkina, N.; Shanin, V.; Saparbekova, A.
Proceeding from the goals of sustainable development of the United Nations and the active introduction of the principles of the circular economy's concept, the possibility of using the secondary raw and material resources in the production processes is relevant. At the UN Environment Assembly in 2022 representatives of 175 countries approved a resolution and called for a joint effort of states to reduce plastic pollution. Biodegradable plastics are a well-known alternative to traditional plastics with a long natural decomposition period. Among biodegradable materials, compostable materials are especially interesting due to the possibility of absolute degradation to biomass, CO2 and water. The problem of obtaining compostable materials is related to the possibility of using secondary material resources and achieving certain quality parameters of the final product. In this research, the criteria and technological solutions for obtaining compostable materials for single use are reviewed. The requirements to the raw plant material and the final product were analyzed, various ways of obtaining such materials and raw material processing methods were investigated. As a result of the work, the ratios of the mixture components were selected, the particle sizes of the plant component were determined, the use of a hot press machine was validated and the technological parameters for obtaining the finished form of the material were determined. The obtained results of the study are planned to be used for the development of production technology of compostable bio-composites and its further scaling for their mass production of bio-composite materials for consumer and industrial needs.
Amino acid composition of milk from Finnish Ayrshire cows and their crossbreeds with the Norwegian Red breed
(Estonian University of Life Sciences, 2023) Ruban, S.; Merzlov, S.; Matvieiev, М.; Borshch, O.V.; Borshch, O.O.; Bilkevich, V.; Lykhach, V.; Fedorchenko, M.; Bondarenko, L.
The purpose of this work was to study the effect of crossing of Finnish Ayrshire cows with Norwegian Red breed under the conditions of the temperate climate of Ukraine on indicators of the qualitative composition of milk, the content of essential amino acids (EAA) and their biological value. The research was conducted at a commercial farm in the Poltava region (50°02′39″ n.l., 33°51′09″ e.l.) using Finnish Ayrshire cows and their crosses with the Norwegian Red breed. According to the indicators of fat, protein and lactose content in the group of crossbred firstborns, purebred counterparts prevailed by: 0.22; 0.09 and 0.07%, respectively, and the energy value of 1 kg of milk by 0.053 Mcal kg-1 . For milk protein of Finnish Ayrshires, the first limiting EAA (lower than the recommended content in the reference protein) was methionine + cystine (affects the rate of clot formation during cheese making), the content of which was 96.3%. In the protein of crossbred cows EAA in which amino acid score (AAS) was less than 100%, were not detected. Phenylalanine + tyrosine - 143.7% and leucine - 122.1%, which are aromatic amino acids and affect the taste properties of milk, were the most excessive. The protein of crossbreds was characterized by a slightly higher value of the total utilitarian coefficient, compared to purebred counterparts (by 12.77%). Also, the aminogram of the crossbred group was closer to ‘ideal’.
Analysis of the power balance of a solar catamaran
(Estonian University of Life Sciences, 2023) Berjoza, D.; Jurgena, I.; Einstals, A.
Significant changes are expected in the percentage distribution of vehicles in the world over the next decade. It is planned to gradually replace conventional internal combustion vehicles with electric drive ones, thereby reducing environment impacts and the production of gases contributing to the greenhouse effect. It is necessary to foster similar trends regarding watercraft, replacing the internal combustion engines with electric motors. An experiment used a solar-powered catamaran equipped with a standard electric motor Minn Kota Endura 34, a 450 W monocrystalline solar cell and a 40 Ah lithium iron 12 V battery. A pyranometer was used to measure solar energy. The experiment used a data logger GL 220 that measured the energy flow to the battery and the electric motor. The experiment was conducted in Jelgava on 5 July 2022, with the maximum altitude of the sun reaching 56.7°. The experiment identified that at an average solar intensity of 500 W m-2 on a sunny day, the solar catamaran could be moved by means of solar energy without discharging the batteries at all power settings.
Knowledge of packaging waste among czech university students
(Estonian University of Life Sciences, 2023) Altmann, V.; Zhao, S.
The residential sector generates around 14% of the overall waste production in the Czech Republic. This essential share requires special attention to analyze with particular emphasis for citizen education, especially on young people. Thus, this research is dedicated to citizens' awareness about packaging waste to increase their knowledge. The experiment was conducted in the form of a survey, and students from a Czech university were asked to estimate the weight of the packaging waste presented to them in term to verify their knowledge about packaging waste. This experiment featured different groups of students over time. The result showed no difference in knowledge between these student groups over time. The long-term home study caused by COVID-19 did not appear to have affected students' knowledge of packaging waste. This study showed students' actual knowledge about packaging waste and highlighted the gap and importance of education in waste management.
Large building facilities towards energy transition
(Estonian University of Life Sciences, 2023) Karapidakis, E.; Markaki, M.; Yfanti, S.
Large buildings complexes present significant amounts of energy consumption. Sport centers compose a more special case of large volume buildings, compared to other facilities. This is related not only to the specific requirements of the thermal environment regarding the type of activities taking place as well as the considerable loads enforced by the presence of people. The aim of this paper is to evaluate the energy consumption of a Sports center, through energy audits, extract energy baselines and propose energy-saving interventions and RES utilization. More precisely, a cost-benefit analysis will be carried out to assess the energy production and the relevant contribution of the potential energy interventions. As a result, the priority list of proposed measures will be extracted, with all the data regarding energy gains, capital costs, and cash flows. Particularly, a capital budgeting analysis of each measure will support the final decision of a holistic energy approach at the specific building facilities.
Psychrophilic plug-flow digester with assisted solar heat – small-scale system feasibility
(Estonian University of Life Sciences, 2023) Ivanovs, K.; Blumberga, D.
Paper discusses using a low-temperature biogas reactor with a solar support system technology as a management tool of biodegradable waste in small scale. A feasibility study looks at primary factors affecting anaerobic digestion process and solar heat production, design examination of a solar heating for anaerobic digester and possible technology application, also defines the multilocality of biogas, illustrates diffusion of innovation for diversification of biogas production. Analysis confirms solar heat increases efficiency and production of biogas, decreases costs and toxicity of digestate. Results show that for implementation of technology in rural areas further research in socio-economic, sourcing of feedstock and customization is needed.
Impact of changing weather on the crops yield stability in different cropping systems
(Estonian University of Life Sciences, 2023) Viikoja, Ragnar; Alaru, Maarika; Keres, Indrek; Lillak, Rein; Voor, Ivo; Loit, Evelin; Estonian University of Life Sciences. Institute of Agricultural and Environmental Sciences. Chair of Crop Science and Plant Biology
Changes in weather conditions make it possible to change the schedule of agricultural works and introduce new crops and crop rotations in Northern Europe. It is important that the yield of the crops in the rotation are stable under highly variable weather conditions, which would ensure a high total yield for the rotation. One of the goals of this long-term field experiment (2008–2022) was to study the effect of weather conditions on the total yield and stability in the crop rotation; crops of the given crop rotation were grown in organic and conventional cropping systems. Compared to the pre-experimental period 1964‒2007, the annual average air temperature of the test period 2008‒2022 was higher by 1.1 degrees, whereas the increase in the annual average temperature was primarily due to the increase in winter and June–July temperatures. In the 3rd cropping cycle (2018–2022) the total yield of crop rotation as an average of fertilizer variants and experimental years was 21% and 24% lower than in the 1st (2008–2012) and 2nd (2013–2017) cropping cycles, respectively, which was mainly caused by the decrease in field pea yield. The effect of weather on yield stability was greatest for field pea. Fertilization with mineral fertilizers improved the stability of the total yield in the conventional cropping system. Correlation, factorial analyses of variance (ANOVA) and two-factor ANOVA were used to test the effect of cropping systems and climatic conditions on total and average DM yield of crop rotation, also each crop’s DM yield. Despite the negative impact of the weather, most of the yield loss can be prevented or the damage can be eased by careful planning and detailed knowledge about the influence of different weather factors. Further investigation is required to determine the change in growing season length, sowing dates and harvesting to provide farmers more detailed tools to predict and plan their actions.
Relation between organizational identification, employee burnout and mental well-being
(Estonian University of Life Sciences, 2023) Geidelina-Lugovska, M.; Cekuls, A.
In this study, relation between employee organizational identification, employee burnout and mental well-being was explored. The main aim of this research was to investigate, whether higher level of organizational identification cause employee burnout, jeopardizing mental well-being. An online survey was created using Qualtrics and participants were recruited via Facebook and LinkedIn in May-July 2022 to measure organizational identification, burnout and mental well-being of employed people (n = 138). Results reveil that even if there is a risk of burnout, mental well-being and organizational identification are quite high. Therefore, mental well-being is not being jeopardized.
Genotype by yield × trait (GYT) biplot analysis for the identification of the superior winter and facultative barley breeding lines
(Estonian University of Life Sciences, 2023) Hudzenko, V.M.; Lysenko, A.A.; Tsentylo, L.V.; Demydov, O.A.; Polishchuk, T.P.; Khudolii, L.V.; Buniak, N.M.; Fedorenko, I.V.; Fedorenko, M.V.; Petrenko, V.V.; Yurchenko, T.V.; Suddenko, Y.M.; Ishchenko, V.A.; Kozelets, H.M.
In the present study, in a panel of promising winter and facultative barley (Hordeum vulgare L.) breeding lines, the peculiarities of yield performance and its combination with resistance (tolerance) to the most common under conditions of the Ukrainian Forest-Steppe abiotic and biotic stresses have been determined. In 2016-17–2018-19 the breeding lines were differentiated based on grain yield, thousand kernel weight, frost resistance, leakage of electrolytes, relative drought tolerance, lodging resistance, and resistance to powdery mildew (caused by Blumeria graminis (DC.) E. O. Speer, f. sp. hordei emend. É. J. Marchal (anamorph Oidium monilioides Link)), spot blotch (caused by Cochliobolus sativus (anamorph Bipolaris sorokiniana [Sacc.] Shoem.)), and leaf rust (caused by Puccinia hordei Otth.). GYT (genotype by yield × trait) biplot model was used for comprehensive evaluation of the breeding lines by a combination of yield with a complex of traits. As a result, the winter breeding line ‘Pallidum 5096’ and facultative breeding line ‘Pallidum 5110’ superior to others in terms of yield × traits combinations have been identified. These breeding lines as new varieties ‘MIP Atlas’ and ‘MIP Yanus’ accordingly have been submitted to the Ukrainian Institute for Plant Variety Examination for further State Qualification Examination. The winter (‘Pallidum 5134’, ‘Pallidum 5097’, ‘Pallidum 5024’, ‘Pallidum 5090’, and ‘Pallidum 5130’) and facultative (‘Pallidum 5153’, ‘Pallidum 5102’, ‘Pallidum 5126’, and ‘Pallidum 5131’) breeding lines can be used as valuable genetic sources in breeding programs in Ukraine and some other Central a nd Eastern European countries.
Comparison of different chemical-free pretreatment methods for the production of sugars, ethanol and methane from lignocellulosic biomass
(Estonian University of Life Sciences, 2023) Sjulander, Nikki; Rooni, Vahur; Rocha-Meneses, Lisandra; Kikas, Timo; Estonian University of Life Sciences. Institute of Forestry and Engineering. Chair of Biosystems Engineering
Most pretreatment methods for lignocellulosic biomass use strong chemicals, such as sulphuric acid and ammonia, to open up the cellular structure of plant biomass. However, those chemicals are not environmentally friendly and their use leads to safety risks. As a result, different chemical-free pretreatment methods have been developed, which focus on the usage of pressure, high or low temperatures and mild chemicals. Freezing pretreatment and explosive decompression pretreatments, using different operating gases, such as nitrogen and steam, are compared in the context of glucose, ethanol and methane yield in this review. For the methane production, the stillage from bioethanol production is used. The usage of this waste improves the overall valorisation of lignocellulosic biomass. The review also investigates, whether the nitrogen explosive decompression pretreatment is suitable for the treatment of softwoods, hardwoods and herbaceous materials. In the comparison of different chemical-free pretreatment methods, it is concluded that heat and water are the most influential parameters for opening up the lignocellulosic biomass structure. The operating gas and pressure in the pretreatment reactor are less relevant. Steam explosion, nitrogen explosive decompression pretreatment and autohydrolysis pretreatment are the most suitable chemical-free pretreatment methods for lignocellulosic biomass.
Changes in the content of soil organic carbon and total nitrogen in the organic and conventional cropping systems
(Estonian University of Life Sciences, 2023) Kuht, Jaan; Eremeev, Viacheslav; Loit, Evelin; Alaru, Maarika; Mäeorg, Erkki; Talgre, Liina; Luik, Anne; Estonian University of Life Sciences. Institute of Agricultural and Environmental Sciences
Maintaining and increasing the stock of soil organic carbon is of vital importance in maintaining the soil fertility. In present research the changes in the content of organic carbon (SOC) and total nitrogen (Ntot) in the soil are investigated. The data is collected from the long-term field experiment, which compares organic and conventional farming systems in a crop rotation (barley undersown with red clover, red clover, winter wheat, pea, potato) during 2014–2018. Based on the 5-year experiment, it was concluded that the cropping systems have a significant effect on the SOC content and a smaller effect on the Ntot content of the soil. The diversification of organic cropping systems with cover crops and composted cattle manure significantly increases the content of organic carbon in the soil. The results of the experiment indicate that the content of organic carbon was significantly lower (by 7.6–12.6%) in conventional systems, where pesticides had been applied and cover crops and manure had not been used, compared to the organic cropping systems. The correlations between the SOC contents of main crops and precrops were statistically more significant in organic farming system, compared to the conventional system. Highest SOC and Ntot values were observed in organic systems with cover crops and composted manure fertilization. Hence, it can be stated that in order to improve the soil fertility and fix more carbon and nitrogen, high amounts of organic material should be applied into the soil and the activity of soil microbes should be a priority. The organic cropping systems have more advantages for sustainable crop production.
Development of a custom-built RTK-GNSS positioning system for agricultural operations
(Estonian University of Life Sciences, 2023) Lajunen, A.; Pietarinen, J.
The objective of this research is to assess positioning accuracy of a custom-built RTK (Real Time Kinematic) base station. Setting up a RTK base station with open-source tools is rather straightforward process requiring only few components and basic programming skills. The base station and receiver unit were developed by using a SparkFun GPS-RTK2 Board with U-Blox ZED-F9P module. The board was paired with U-blox Multi band GNSS (Global Navigation Satellite System) antenna. The board can use GNSS satellite signals from Galileo, BeiDou, Glonass and GPS systems. The positioning accuracy was evaluated in a fixed position and during operations in agricultural fields. The RTK correction signal was used in connection with soil scanning measurements in different crop fields of the Viikki Research Farm of the University of Helsinki. For accuracy assessment, comparative measurements were carried out with a commercial network RTK (NRTK) correction signal. The vertical and horizontal accuracy of the positioning signal were evaluated based on the accuracy variables calculated by the receiver. The vertical accuracy was also evaluated by mapping the scanned trajectories on the height map which was obtained from NSL (National Land Survey of Finland) open map data service. The custom-built RTK positioning system accuracy was considered generally precise enough for autonomous field work, but the reliability of the observed accuracy should be confirmed with more extensive measurements. The commercial NRTK signal accuracy was considered very good and reliable also for the vertical direction.
The effect of plant growth regulators on productivity of lavender (Lavandula angustifolia Mill.) in the conditions of the Southern Steppe of Ukraine
(Estonian University of Life Sciences, 2023) Manushkina, T.; Kachanova, T.; Samoilenko, M.
The current state of the essential oil industry in Ukraine requires the expansion of areas for essential oil crops. Nowadays, the demand for natural vegetable raw materials and lavender essential oil is growing. Therefore, the aim of the research was to study the morpho-biological features and productivity of lavender plants by treatment with plant growth regulators Radostim and Stimpo during the third-fifth years of the growing season in the Southern Steppe of Ukraine. The research was conducted during 2018–2020. The material for the research work was lavender plants such as Lavandula angustifolia Mill., the varieties of Sinieva and Vdala. The field experiment was done with the method of split randomized blocks. The research was accompanied by phenological, biometric, structural and laboratory observations in accordance with generally accepted methods. Treatment with the growth regulator Stimpo has the greatest stimulating effect on the processes of growth and productivity in lavender plants. Using this method, the highest yield was formed in all years of vegetation from 6.70 to 7.90 t ha-1 at standard humidity, which is by 14.8–21.1% more than in the control. The mass fraction of essential oil in vegetable raw materials is quite high (1.85–2.32%), it differs in lavender varieties and does not depend on treatment with plant growth regulators. The largest harvest of essential oil in all years of vegetation was obtained by treating plants with the growth regulator Stimpo from 137.30 up to 147.36 kg ha-1 , which is by 15.9–16.7% more than in the control.
Physical parameters kinetics during the drying process of quarters and halves cut tomatoes
(Estonian University of Life Sciences, 2023) Mencarelli, A.; Marinello, F.; Marini, A.; Guerrini, L.
Tomato drying is a time-consuming industrial process. Moreover, the prolonged use of high temperatures decreases the quality of tomatoes and increases the environmental footprint of the process. In most cases, drying is performed on halved tomatoes. Alternatively, the use of quarter tomatoes could guarantee a drying times reduction without compromising the final product quality. This work aimed at modelling changes in physical characteristics of half and quarter tomatoes. The drying tests were conducted at 50 and 60 °C. The kinetics of weight loss, colour change, and volume reduction were determined. Colour change was monitored through image analysis, while volume reduction using RGB-D reconstructions. Based on the results, an increase in the drying temperature and the use of quartered tomatoes allow a significant reduction in drying times. The loss of water kinetic allowed the determination of critical moisture. Between initial and critical moisture, loss of water occurred at constant rate (zero-order kinetic), while after that the rate decreased exponentially (first-order kinetic). The colour kinetics showed an initial constant rate followed by a linear increase for brown pixels. The variation of red pixels did not have a clear trend. Increasing the temperature there was no significant reduction in colour quality while quarter tomatoes showed a greater loss of redness than halved tomatoes. Furthermore, the temperature increase does not affect the volume reduction of the tomatoes. Increasing the temperature and the use of quartered tomatoes are simple solutions to reduce drying times. However, quartered tomatoes are less visually appreciable than halved tomatoes.

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