2021, Vol. 19, No. 2

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/6854

Sirvi

Nüüd näidatakse 1 - 20 28

Influence of humic acids, irrigation and fertilization on potato yielding in organic production
(2021) Kołodziejczyk, M.
The study aimed at determining the impact of organic fertilization, humic acids and irrigation on potato yielding in organic production system. Fertilization variants included: Humac Agro; manure; vermicompost; Fertil Bioilsa C-N 40-12.5; manure + Humac Agro; vermicompost + Humac Agro; Fertil Bioilsa C-N 40-12.5 + Humac Agro. Irrigation was carried out using drip lines. The highest tuber yield was determined on treatments fertilized with vermicompost. The combined application of organic fertilizers and humic acids resulted in increased total yield between 6 and 9%, whereas commercial yield from 5 to 10%. Application of fertilization resulted in increased total yield of tubers in individual fertilizer variants from 1.9 to 10.8 t ha-1 , and commercial yield from 1.6 to 12.3 t ha-1 . Water-use efficiency remained in the range from 35.2 to 113.1 kg mm-1 , whereas irrigation water-use efficiency from 9.9 to 166.3 kg mm-1 . Humic acids used in the study enhanced fertilizer and water-use efficiency.
The food security concept as the state support basis for agriculture
(2021) Zhichkin, K.A.; Nosov, V.V.; Zhichkina, L.N.; Ramazanov, I.A.; Kotyazhov, I.A.; Abdulragimov, I.A.
The article discusses the problem of the country (territory) food security formation and its relationship with the state support size for agriculture. The work purpose is to determine the features of the food security formation in the Samara region and the relationship with the state support size for agricultural production in the region. Within this study framework, it is necessary to solve the following tasks: - study the features of the food security concept and its application in the Samara region conditions; - the optimal parameters of the region's self-sufficiency determination in food products; - establishing a link between food security and the optimal amount of state support for the agro-industrial complex. Taking into account only the data on the region self-sufficiency, the region produces a sufficient amount of potatoes and vegetables. Comparing these indicators with rational consumption rates, it can be seen that the residents' demand for agricultural products is provided mainly by potatoes, the consumption of which is 1.5 times higher than the rational. The subsidies existing system in the Samara region is not optimal from the point of view for ensuring food security, which indicates either the underfunding of the production for both these and other product groups. In 2017–2018 the amount of state support, based on the above calculations, had to be increased by at least 100–500 million rubles.
Fatty oil accumulation in vegetable soybean seeds and its thin-layer chromatography
(2021) Shafigullin, D.; Kask, Sergey; Gins, M.; Pronina, E.; Demyanova-Roy, G.; Soldatenko, A.
This paper studies the accumulation of crude oil (triacylglycerides, monoacylglycerides, diacylglycerides, free fatty acids, phospholipids, tocopherols, pigments, sterols, waxes) in soybean vegetable samples. Samples were taken from two groups: grown in an experimental field and in protected ground of the Federal Scientific Center for Vegetable Growing in the Moscow Region. Both groups were observed in the phase of technical ripeness and in the phase of complete biological ripeness (finally ripe seeds). Soxhlet method as arbitration in analysis was used as suitable for the extraction of lipophilic substances. It was determined that the fat content in the technical ripeness phase in most soybean samples averaged 10.5%. In the phase of biological ripeness, the highest accumulation of fatty oil was observed in Hidaka and Nordic (17.6%). The oil content in vegetable forms of soybeans was consistently lower than that of grain varieties: in the phases of technical and biological ripeness by 55.6% and 22.0% (in relative values) respectively. Thus, he accumulation of oil in seeds is determined mainly genetically. The refractive index of vegetable and oil soybean was established equal on average 1.4755. According to this finding the soybean oil can be classified as semi-drying. Thin layer chromatography (TLC) was used to study the lipophilic components of soybean fatty oil. It was found experimentally that the best separation of the components is achieved using an eluent system: carbon tetrachloride: chloroform in a 2: 3 ratio. It was found that the main fatsoluble compounds are the following (in order of increasing Rf in the chromatogram): phospholipids, monoacylglycerides, triacylglycerides, tocopherols, fatty acid esters. As a finding of the research vegetable soybean cultivated at 55 °N in both technical and biological ripeness phases significantly accumulate crude oil in the seeds. This crude oil contained ω-6, ω-3, phospholipids, and vitamin E.
Differentiated application of nitrogen fertilizers based on optical sensor readings
(2021) Shchuklina, O.; Afanasiev, R.; Voronchikhina, I.; Klimenkova, I.; Komkova, A.
The article considers the method of variable rate application of top dressing with nitrogen fertilizers in spring barley crops in the system of precise agriculture. The principle of is based on the in-process diagnosis of plants state in key phases of development and the introduction of necessary dose of top dressing in specific field areas. To assess the plants state, a GreenSeeker optical sensor, which measures the NDVI (Normalized Difference Vegetation Index). The tailored application of top dressing increases the yield of spring barley grain by 14.2% compared to the application of fertilizers with one calculated rate for the entire plot or field (Skudra, 2017, Hamann, 2020).
The effect of succinic acid on the productivity of Lactuca sativa L. in artificial agroecosystems
(2021) Knyazeva, I.V.; Vershinina, O.V.; Gudimo, V.V.; Grishin, A.A.; Dorokhov, A.S.
The research of the effect of the biostimulant on the growth and development of plants of the ‘Robin’ lettuce variety was carried out in 2019–2020 in the department of closed artificial agroecosystems for crop production on the basis of the Federal State Budgetary Scientific Institution «Federal Scientific Agroengineering Center VIM», Moscow (VIM, Russia). Succinic acid was used at the stage of inoculation of seed and with constant drip irrigation of plants throughout the growing period. Lettuce plants were grown using a low-volume technology in a climatic chamber produced by VIM (Russia). According to the studies carried out, inoculation of seeds stimulates the development of plants at the initial stages, reducing the period from sowing to germination and increasing the rate of plant growth. As the lettuce plants grew, the leaf surface area increased from 221.0 to 1511.9 cm² with the addition of succinic acid to the hydroponic nutrient solution. The use of succinic acid under controlled growing conditions of ‘Robin’ lettuce plants allowed to increase the performance of the leaf apparatus in relation to the control. It was experimentally established that productivity directly depended on the value of photosynthetic potential and net productivity of photosynthesis, which is confirmed by a strong degree of dependence with a correlation coefficient of 0.98 and 0.77, respectively. Seed treatment and adding succinic acid to the hydroponic solution increases the accumulation of dry matter in lettuce plants. With this method of using succinic acid, significant differences in the accumulation of dry mass of plants were established. The share of the effect of the factor of inoculation of seeds with succinic acid was 17.5%, the addition of hydroponics to the nutrient solution was 50.1%. The use of succinic acid increases the accumulation of plant biomass, increases the total leaf surface area, and also contributes to an increase in the parameters of photosynthetic activity of the leaf apparatus of the ‘Robin’ lettuce plants under controlled conditions of the climatic chamber.
Analysis of the Foeniculum vulgare Mill. collection by the complex of features in the conditions of the Crimea foothills
(2021) Zolotilova, O.M.; Nevkrytaya, N.V.; Zolotilov, W.A.; Ametova, E.D.; Scipor, O.B.; Kravchenko, G.D.
Foeniculum vulgare Mill. is a valuable essential oil plant, which raw materials and derived products, and, above all, essential oil, are widely used in the perfume and cosmetics, liquor, paint and varnish industries, in the food industry and medicine. The source material for cultivated plants selection, including F. vulgare, is the collections of the gene pool. The objective of this study was a comparative study of F. vulgare samples collection by the complex of features to clarify the possibility of identifying sources of economically valuable characteristics for creating promising breeding material. The study of the F. vulgare collection supported by the Research Institute of Agriculture of Crimea, which includes 75 samples rom 28 countries, was conducted in 2017–2019 at an experimental base located in the Crimea Foothills (Krymskaya Roza village, Belogorsky district). The collection samples were analyzed according to morphobiological parameters and productivity indicators. The work was guided by generally accepted methods, including those developed for essential oil plants. Statistical processing of the obtained data was carried out. The wide variability of the collection is shown, according to individual indicators (variation coefficients - from 8.3 to 54.4%). In this way, the mass fraction of essential oil (one of the most important indicators) varies within a wide range in the collection - from 1.09 to 3.86% (of absolutely dry mass) in whole plants and from 4.16 to 8.53% in fruits. The composition of the essential oil depends on the raw material. The anethole content reaches 80% in fruit oil, and the content of fenchone and terpene compounds is increased during the plant processing. The results of the collection analysis are basic, allowing preliminary sampling with high productivity indicators for inclusion in breeding studies.
Productivity of winter wheat in the northern Steppe of Ukraine depending on weather conditions in the early spring period
(2021) Mostipan, M.; Vasylkovska, K.; Andriienko, O.; Kovalov, M.; Umrykhin, N.
The objective of the research was to develop scientific and methodological bases for adapting the technology of growing winter wheat depending on weather conditions in early spring. Winter wheat was grown at different sowing dates. It is established that the reserves of productive moisture in the soil at the time of renewal of spring vegetation are crucial for the formation of winter wheat harvest. After worse forecrop, the impact of moisture on productivity reaches 49.7–66.4%. The later the renewal of spring vegetation of winter wheat is, the lower the productivity of the crops. The shorter the period from the date of transition of the average daily air temperature above 0 °C to the beginning of active vegetation of plants is, the higher the productivity of winter wheat crops. Therefore, depending on weather conditions of early spring period and the time of renewal of spring vegetation of plants, it is necessary to adjust the technology of growing winter wheat during the spring-summer period.
Fixed nitrogen in agriculture and its role in agrocenoses
(2021) Tanchyk, S.; Litvinov, D.; Butenko, A.; Litvinova, O.; Pavlov, O.; Babenko, A.; Shpyrka, N.; Onychko, V.; Masyk, I.; Onychko, T.
On typical low-humus black soils in short crop rotations with legumes (25–33%) and without them, it was found that depending on the set of crops in crop rotation and application of fertilizer rates, nitrogen yield per crop is from 355 kg ha-1 to 682 kg ha-1 . The recommended fertilization system provided nitrogen compensation for crop yields by only 31–76%. Hence, in the plant-fertilizer system nitrogen deficiency varies from 161 to 370 kg ha-1 . The greatest nitrogen deficiency in the soil is observed in crop rotation without the use of fertilizers with the following crop rotation: peas-winter wheat-grain maize-spring barley. The main source of nitrogen for plants is soil nitrogen. In crop rotations with legumes, biological nitrogen is supplied from the air, which in quantitative terms per rotation in crop rotations with peas is 109–288 kg ha-1 , with soybeans 264–312, and with alfalfa 486 kg ha-1 . Biological nitrogen in crop rotations with peas and soybeans is reimbursed from 25 to 62%, in crop rotation without legumes - 9% (non-symbiotic nitrogen fixation), and in crop rotation with alfalfa - 89% of the total nitrogen removal with the crop.
Effect of superabsorbent on soil moisture, productivity and some physiological and biochemical characteristics of basil
(2021) Havrilyuk, M.; Fedorenko, V.; Ulianych, O.; Kucher, I.; Yatsenko, V.; Vorobiova, N.; Lazariev, O.
The study was carried out in 2019–2020, in the conditions of the Right-Bank ForestSteppe of Ukraine. The results on the influence of absorbents in gel and powder forms on the productivity of basil plants (Ocimum basilicum L.) are presented. For research were used field, laboratory, statistical and calculation-analytical methods. Absorbent in the form of a gel was used while transplanting: dip the roots of the plant in the solution and then transplant in the field. Absorbent in the form of a powder - 5 kg ha-1 , application of the absorbent into the soil layer 20–25 cm-1 . Absorbents contributed to a slight decrease of sugar content (-0.86–2.68% in the cultivar of Badioryi, -1.48–2.35% in the cultivar of Rutan), significantly decrease ascorbic acid (-8.6–20.1%) and content of the essential oil (8.0–19.4%) and indirectly increased essential oil yield by increasing fresh weight yield in both varieties. The activity of APX, CAT, SOD, tended to decrease in all variants of the experiment, regardless of the form of the absorbent. APX (-12.8–35.1%), CAT (-10.9–22.0%), SOD (-11.9–17.0%). Higher yields were observed in the version with the introduction of the absorbent in the form of a gel. Thus, the yield of the cultivars of Badioryi and Rutan exceeded the control by 52.67 and 50.05%, in accordance. The productivity of basil is increased with the use of superabsorbent polymers. This practice can be recommended to agricultural producers who grow vegetables, in particular, basil in areas of unstable or insufficient moisture.
Evaluation phenology, yield and quality of maize genotypes in drought stress and non-stress environments
(2021) Horváth, É.; Gombos, B.; Széles, A.
The aim of the study is to examine the effect of agrometeorological indices (growing degree days, GDD; heliothermal unit, HTU; photothermal unit, PTU; hydrothermal unit, HYTU) on the phenology and yield (GY) of the Sushi (FAO 340) and Fornad (FAO 420) maize hybrids. Furthermore, it was also analysed how the amount of nitrogen and its application time affected the productivity and protein content (GP) of maize under drought stress (DS) and non-stress (NS) conditions. There were seven fertilizer treatments in the scope of the field experiment. Non-fertilized treatment (A0) spring basic treatment with 60 and 120 N ha-1 (A60, A120), and following the basic treatments, 30 kg N ha-1 top-dressing was applied in the V6 (V690, V6150) phenophase and then another 30 kg N ha-1 in the V12 (V12120, V12180) phenophase. Based on the GDD and PTU, length of the vegetation period of maize hybrids can be predicted. Under DS, the largest GY and GP was recorded in the same treatment for Sushi (V6150 kg N ha−1 ), and at different nutrient levels under NS: GY (A120) and GP (V6150). The highest GY of Fornad hybrid under DS was achieved with the A120 treatment while the highest GP with the V6150; in the case of NS V6150 kg N ha−1 was the most effective for both GY and GP. The + 30 kg ha-1 N fertilizer applied in the V12 phenophase did not improve GY and GP in either hybrid during the two growing seasons. The findings provide useful help for farmers to prepare for future environmental changes and to operate successfully.
Evaluation of selected soft winter wheat lines for main ear grain weight
(2021) Lozinskiy, M.; Burdenyuk-Tarasevych, L.; Grabovskyi, M.; Lozinska, T.; Sabadyn, V.; Sidorova, I.; Panchenko, T.; Fedoruk, Y.; Kumanska, Y.
Studies to assess the breeding samples of soft winter wheat by weight of grain from the main ear anddetermine the indicators of adaptability were conducted at the Bila Tserkva Research and Selection Station (BTRSS) in 2011–2013. The study revealed significant differences in breeding lines in the range of variability of grain mass from the main ear and identified small, medium and significantcoefficients of variation, which indicates their excellent response to environmental conditions. It was due to genotype, year conditions and their interaction. Line 42 KS had significantly higher than the standard grain weight of the main ear (0.14 g) and the lowest value of the coefficient of variation (8.7%). According to the indicators of adaptability(GAC, σ²(GxE)gi, σ²SACi, σSACi, etc.) the lines 42 KS, 24 KS and 44 KS were distinguished. There was asignificant correlation between the weight of grain from the ear and the weight of 1,000 grains (0.603–0.674) and the direct influence of the weight of grain from the main ear on the weight of grain from the plantand grain yield (0.805–0.942). Selected lines as a result of research (2015–2020) from these populations of soft winter wheat are competitively tested in the conditions of Bila Tserkva Research and Selection Station, forming high grain yields (7.39–8.12 t ha-1 ) and will be transferred to 2021 for the State variety test for inclusion in the Register of plant varieties suitable for distribution in Ukraine.
Investigating Calotropis Procera natural dye extracts and PDOT:PSS hole transport material for dye-sensitized solar cells
(2021) Alami, A.; Alachkar, A.; Alasad, S.; Alawadhi, M.; Zhang, D.; Aljaghoub, H.; Elkeblawy, A.
In this work, natural dye extracts from Calotropis Procera are used as the main dyesensitizer in solar cells. The Calotropis plant is a non-food item capable of surviving the harsh climate of the United Arab Emirates. Its incorporation into dye-sensitized solar cells is tested by constructing various cells, whose performance was also compared to that of more common chlorophyll-based dye extracts (i.e. spinach) as well as compared against a baseline cell sensitized with a synthetic ruthenium dye. The performance of the Calotropis-based cells was in general better than those with other natural sensitizers, but of course scored lower efficiency results when compared to cells built with synthetic dyes (0.075% compared to 5.11%). The advantage in using a natural sensitizer include facile extraction and preparation, low cost and abundance, since the Calotropis source has no competing applications in terms of food, livestock feed, etc. The figureof-merit of cell output vs. cost for such cells makes them a good contender for further research and development effort to overcome the obvious drawbacks of stability and service longevity. Adding a hole-transport material to the cells in the form of PEDOT:PSS was also attempted to assess the enhancement it could provide to the cells. This did not yield the desired results and more experiments have to be done to better understand the interaction of each added layer to the original cell design.
Evolution of production and forage quality in sown meadows of a mountain area inside Parmesan cheese consortium
(2021) Argenti, G.; Parrini, S.; Staglianò, N.; Bozzi, R.
Sown meadows, encompassing alfalfa and grass-legume mixtures, are the forage crops on which is based Parmesan cheese production system in the mountain area of the Apennines (central Italy). These grassland types experience, during their development, deep changes in terms of production potentiality, botanical composition and forage quality, thus these meadows have to be periodically renewed to guarantee adequate productive and qualitative performances. To have an accurate assessment of this evolution along time, a survey was performed in different mountain farms inside the Parmesan cheese consortium, analysing alfalfa meadows and grass-legumes mixtures of different ages. Grasslands were monitored during 2019, performing three samplings during growing season. Aboveground biomass production, botanical composition and crude protein content were collected during the survey. Results permitted to evaluate the level of production decrease along years, the evolution of analysed parameters among cutting dates and the dependence of productive and qualitative features on botanical composition and presence of sown species in the swards. Results were useful to hypothesize the composition of future mixtures, to improve management issues and to delineate the possible duration of sown meadows for the area with respect to different purposes in terms of desired productive or qualitative objectives.
Apple scab detection using CNN and Transfer Learning
(2021) Kodors, S.; Lacis, G.; Sokolova, O.; Zhukovs, V.; Apeinans, I.; Bartulsons, T.
The goal of smart and precise horticulture is to increase yield and product quality by simultaneous reduction of pesticide application, thereby promoting the improvement of food security. The scope of this research is apple scab detection in the early stage of development using mobile phones and artificial intelligence based on convolutional neural network (CNN) applications. The research considers data acquisition and CNN training. Two datasets were collected - with images of scab infected fruits and leaves of an apple tree. However, data acquisition is a time-consuming process and scab appearance has a probability factor. Therefore, transfer learning is an appropriate training methodology. The goal of this research was to select the most suitable dataset for transfer learning for the apple scab detection domain and to evaluate the transfer learning impact comparing it with learning from scratch. The statistical analysis confirmed the positive effect of transfer learning on CNN performance with significance level 0.05.
Enzymatic activity of podzolized chernozem contaminated by pollutants during its detoxification
(2021) Chernikova, O.; Mazhayskiy, Yu.; Ampleeva, L.
The soil is an indicator of the general technogenic situation. In terms of the scale of pollution, as well as the impact on biological objects, heavy metals occupy a special place among pollutants. One of the priority pollutants are Pb, Cd, Zn, Cu. In assessing the ecological state of the environment, the study of the soil cover plays an important role. The most informative integral characteristics of the biological activity of the soil is the activity of soil enzymes. In a lysimetric experiment with podzolized chernozem, we studied the change in the biological activity of soil in terms of dehydrogenase, catalase, urease, invertase and phosphatase enzymatic activity under the complex influence of heavy metals under conditions of the use of detoxification agents. The soil at the experimental site had the following characteristics: pHKCl 6.2; humus content - 3.2%, P2O5-229 mg kg-1 , K2O-250 mg kg-1 of soil. Organic and mineral fertilizers in various combinations were used as detoxifiers. According to the obtained data, the redox enzyme - dehydrogenase and hydrolytic enzymes urease and phosphatase are the most sensitive to soil pollution. The best decontamination effect is obtained when using a system of organo-mineral fertilizers, what contributes to an increase in the activity of soil urease by 3.38 times, invertase - by 2.47 times, phosphatase - by 1.48 times, dehydrogenase - by 1.46 times, catalase - by 1.60 times. Changes in the activity of these enzymes can be used to diagnose the effectiveness of the use of various fertilizer systems on soil contaminated by heavy metals.
Comparison of the effect of ultraviolet light, ozone and heat treatment on muesli quality
(2021) Lignicka, I.; Balgalve, A.; Ābelniece, K.; Zīdere-Laizāne, A.M.
Various muesli processing technologies can be used to lower microbiological parameters. It is necessary to find the best treatment technology to ensure that the product can meet various regulatory limits and to increase the shelf life of the product. The aim of this study was to compare the effect of ultraviolet light, ozone treatment and sterilisation on muesli quality. Muesli samples with dried fruits were tested, comparing the change in total plate count, yeast count and mould count. Short-wave ultraviolet (UV-C) light with a wavelength of 254 nm was used for ultraviolet light treatment, and the product was treated for 1, 2, and 5 minutes. As for ozone treatment, the samples were treated with an ozone concentration of 35 ppm for 30 minutes. Heat sterilisation was performed using sterilisation mode 25-30-50 (heating, holding, cooling), 119 °C, 2.2×105 Pa. Ultraviolet light and ozone treatment did not have a significant impact on total plate count, yeast count and mould count. Heat sterilisation had the most significant effect on muesli sample microorganism level, total plate count, yeast count and mould count level were 10 log cfu g -1 .
Activation effect of β-alanine and chitosan derivative on A. glycyphyllos and A. membranaceus seed germination and seedling growth and development
(2021) Khamidullina, L.A.; Cherepanova, O.E.; Tobysheva, P.D.; Rybina, E.A.; Pestov, A.V.
Agricultural cultivation of astragalus is fraught with a number of difficulties caused by both certain requirements for climatic conditions and individual characteristics of plants of this genus. In this study, carboxyalkylated derivative of chitosan was first proposed to use for improvement of astragalus propagation. Effects of N-(2-carboxyethyl)chitosan on in vitro A. glycyphyllos and A. membranaceus seed germination and seedling growth and development in comparing with β-alanine and chitosan acetate were detected. Carboxyethylation of chitosan leads to an increase in hydrophilic properties of the molecule, which enhances a penetration of nutrients inside the plant owing to improved solvating effect and bioadhesive activity. Seed germination assay were performed on Murashige-Skoog growth medium with or without tested compounds. N-2-Carboxyethylated derivative of chitosan was found to demonstrate active stimulating effect on the plant growth and development, contrary to the effect of acetate chitosan, but not to cause an activating effect on seed germination, while β-alanine does.
Airflow resistance of two hop varieties
(2021) Ziegler, T.; Teodorov, T.
The quality of hops used in brewing is substantially reliant upon the processing step of drying. To ensure effective drying in kiln as well conveyor-belt dryers, homogeneous distribution of air is of particular importance. Uneven air distribution often results in inefficient drying and nonuniform moisture content of the hop cones. The air distribution naturally is governed by the airflow resistances in the individual floors or belts of a dryer. Hence, in order to quantify the airflow resistance of hop cones at different air velocities and bed heights, systematic measurements were carried out. In addition to determining the bulk densities of hops, the investigations included trials with fresh and dried hop samples. Clear differences were observed between hop varieties both in measured pressure drops and in bulk densities. Moreover, in the case of fresh hops, a non-linear increase in pressure drop with bed height was ascertained. Semiempirical equations were developed to describe pressure drop as a function of air velocity. This work will contribute to the design of dryers with optimum airflow distribution and thus enhance the efficiency of drying as well as the product quality.
Relationship between somatic cell count in goat milk and mature Kashkaval cheese parameters
(2021) Balabanova, T.; Ivanova, M.
It is challenging to ensure Kashkaval cheese consistent quality during the production process which is directly correlated to the somatic cell count (SCC) and bacterial presence. This is one of the most popular and widely discussed topic areas in the dairy industry. SCC is used to limit the inflammatory process and to predict the health status of the animal’s mammary glands. The objective of this study was to evaluate the quality characteristics of mature Kashkaval cheese was produced from goat milk with different SCC (below 1,200 thous cells mL-1 - group I (low), above 1,750 thous cells mL-1 - group II (high) and up to 1,600 thous cells mL-1 - group III (medium)) and samples were evaluated on the 1st and 60th day of ripening by chemical, microbiological and sensory profile. The results showed a significant relation (P < 0.05) between the levels of SCC and Kashkaval cheese water content during ripening. For all analysed samples, the total lactic acid bacterial count was the highest between the 15th and 45th day of ripening and reached values up to 6.0 log cfu g -1 . Pathogenic microorganisms (Listeria monocytogenes, Coagulase-positive staphylococci) and coliforms were not detected. The highest number of psychrotrophic microorganisms was observed in Kashkaval samples with high SCC. The sensory evaluation revealed a higher score for cheese samples with low and medium SCC in comparison to the cheese sample with a high SCC.
Some physical and mechanical properties of wood of Fast-growing tree species eucalyptus (Eucalyptus grandis) and radiata pine (Pinus radiata D.Don)
(2021) Iejavs, J.; Podnieks, M.; Uzuls, A.
Fast-growing imported plantation tree species have become an available wood resource for Europe’s wood industry in the last decades. This sustainable alternative may reduce the gap between the increasing demand for and decreasing supply of the local tree species. The aim of the study was to determine and compare basic physical and mechanical properties of eucalyptus (Eucalyptus grandis) wood from Uruguay and radiata pine (Pinus radiata D.Don) wood from New Zealand as an alternative for Scots pine (Pinus sylvestris L.) from Latvia, to produce non– structural semi–finished glued laminated timber members for the manufacturing of windows. Such properties as density, swelling, bending strength, bending modulus of elasticity, compression strength and resistance to impact were determined according to ISO 13061 series standards test methods for small clear wood specimens. As the result of this study it was established that there is not significant difference between the majority of radiata pine and Scots pine properties, with the exception of resistance to impact and radial swelling where radiata pine shows significantly higher values. Not surprisingly all the properties of deciduous eucalyptus wood were significantly higher compared to both coniferous tree species. Higher swelling and density properties of eucalyptus compared to radiata pine and Scots pine should be taken into consideration for the design and production of wooden window elements.

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