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2021, Vol. 19, No. 1

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  • Kirje
    Algae processing for energy production: development of waste pyrolysis technology : [Retracted]
    (Estonian University of Life Sciences, 2021) Bisters, V.; Kalviss, J.; Burlakovs, J.; Klavins, M.
  • Kirje
    Molecular discovery of new allele associated with loose smut resistance gene Ut-X in spring wheat
    (2021) Draz, I.S.; Darwish, A.K.; Abou-Elseoud, M.S.; Elassal, A.A.; Komeil, D.A.
    Genes of resistance to loose smut incited by the fungus Ustilago tritici (Pers.) Rostr. are still unknown in the Egyptian spring wheat. Loose smut incidence (LSI) was assessed in ten wheat cultivars through a two-year field trial during 2018–2020. All of the tested cultivars exhibited various percentages of susceptibility (> 10–70% LSI) to the disease except cultivar Misr-3 which exhibited resistance. The most susceptible cultivars were Sakha-93 (60%), Giza-168 (42.1%), and Misr-2 (34.28%). However, the resistant cultivar Misr-3 recorded the least LSI amounting to 5%. The wheat cultivars were screened by the SCAR marker (Xcrc4.2) to identify the presence/absence of loose smut resistance gene Ut-X. Molecular data revealed that the SCAR marker (Xcrc4.2) generated two alleles in cultivars with PCR fragments size of 800-bp and ≃200-bp. The favorable allele 800-bp was generated only in the resistant Egyptian cultivar ‘Misr-3’ and the resistant check cultivar ‘Biggar’, indicating the presence of the gene. Meanwhile, another allele ≃ 200-bp was generated in seven Egyptian cultivars, Giza-168, Giza-171, Misr2, Sakha-93, Gemmeiza-12, N-95, and Shandweel-1, indicating the absence of the resistant gene. This is the first study to report resistance genes to loose smut in Egyptian spring wheat, by detecting Ut-X in cultivar Misr-3. In addition, the study documented the first report of another allele ≃200-bp associated with SCAR marker (Xcrc4.2). Findings also revealed that the race-specific resistance gene Ut-X confers effective resistance to local U. tritici races, including race T10 which could be widely incorporated in breeding programs to control the disease.
  • Kirje
    Zinc content in different muesli samples
    (2021) Lignicka, I.; Balgalve, A.; Zīdere-Laizāne, A.M.
    There is no specialized zinc storage system in the body, therefore there must be a daily intake of zinc to achieve a steady state. Long-term zinc deficiency due to inappropriate nutrition may result in immunological or autoimmune diseases. The aim of this study was to develop muesli with naturally high zinc content. Zinc is found in various plant-based foods as grain flakes and seeds which often are one of the raw materials for muesli. Muesli is one of the grain-based food trends nowadays as people`s life habits are changing due to fast-paced life, still, it is important to obtain all nutrients. According to zinc content in raw materials five different muesli samples were prepared, from all samples, muesli with the highest zinc content with 3.80 mg 100 mg-1 was chosen for further analysis. Zinc bioavailability is assessed through the determination of absorbability. The kinetic in vitro intestinal digestion suggests how much zinc is released during digestion and could be absorbed in the small intestine. The results show that during digestion approximately 22% of zinc was absorbed in the small intestine. Such characteristics of in vitro digestion test shows that by one meal (50 g of muesli) it is possible to replenish our body zinc level by 0.42 mg. To check additional nutrient content in selected muesli samples different mineral and vitamin analyses were done. Mineral and vitamin content in the muesli sample was calculated according to their content in raw materials. Per portion, muesli is source of iron, magnesium, phosphorus, zinc, vitamin B1, vitamin B2, vitamin B3, vitamin B6 and vitamin E.
  • Kirje
    Experimental research into uniformity in spreading mineral fertilizers with fertilizer spreader disc with tilted axis
    (2021) Bulgakov, V.; Adamchuk, O.; Pascuzzi, S.; Santoro, F.; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
    Improving the efficiency in the work process of mineral fertilizer dressing is a topical problem in today’s agricultural industry. The authors have developed a design of the fertilizer spreading tool with a tilted axis and carried out field experiment investigations on it. It has been established by the results of the investigations that the non-uniformity in the spreading of mineral fertilizers along the line of their departure from the fertilizer spreading tool with a tilted axis is most strongly affected by the disc rotation frequency. The obtained results provide for selecting the optimum parameters and modes of operation for the tool under consideration in the situation, when it is installed in fertilizer placing machines. Also, it has been established that increasing the spreading disc rotation frequency in such a tool from 600 to 800 rpm results in the growth of the effective range of mineral fertilizer spreading along the placing line at a level of 10.5 m. Increasing the disc’s angle of inclination to the horizontal plane to 20º results in the rise of the effective fertilizer spreading range at a level of the 48th tray (24 m) inclusive as well as the increase of the distance between the tool and the tray that contains the maximum share of the spread fertilizers (5.1%) to 24 trays (12 m). At a constant rotation frequency of the disc in the tilted-axis fertilizer spreading tool, in all its kinematic modes of operation, an increase in the angle of its disc’s inclination to the horizontal plane results in the rise of the indices representing the distribution of the mineral fertilizers over the trays along the line of their placing. The width of the mineral fertilizer spreading can be controlled by adjusting the rotation frequency of the disc in the tilted-axis fertilizer spreading tool, when it is set at an angle to the horizontal plane, similar to how it is done in state-of-the-art fertilizer placing machines with horizontally positioned discs in their centrifugal spreading tools. The rotation frequency of the disc in the tilted-axis fertilizer spreading tool has the most significant effect on the coefficient of variation incidental to the distribution of the mineral fertilizers along the line of their placing.
  • Kirje
    Evaluation of soil properties, irrigation and solid waste application levels on Cu and Zn uptake by industrial hemp
    (2021) Golia, E.E.; Angelaki, A.; Giannoulis, K.D.; Skoufogianni, E.; Bartzialis, D.; Cavalaris, Ch.; Vleioras, S.
    Α three-year experiment was performed to study the alteration of copper and zinc levels in industrial hemp grown in different soils using elevated sewage slurry solid waste applications. Two soil samples, an acidic and an alkaline one, with different soil properties, such as percentage of CaCO3 and cation exchange capacity values, were used. Three treatments of waste solid with provided elevated concentrations of Cu and Zn were combined with two irrigation levels. The application of high doses of the solid residue as well as high irrigation level lead to an increase of the mobility of metals in hemp leaves in acidic soil in contrast to alkaline. On the contrary, in alkaline soil along with a reduced irrigation level, there is a decrease in the mobility of Cu and therefore its accumulation in the roots or stems was observed. Concluding, hemp seem to be a promising plant remediator, after the application of the proper irrigation level and taking into account the physico-chemical soil properties of moderately contaminated (with copper and zinc) soils.
  • Kirje
    Variation of chickpea nodulation in a Mediterranean agroecosystem: relationship with soil characteristics and thresholds for significant contribution to plant growth
    (2021) Chenene, Y.; Blavet, D.; Belalmi, M.; Kaci, G.; Teffahi, M.; Ounane, S.M.
    This study was designed to investigate the influence of some environmental constraints on chickpea (Cicer arietinum L.) growth and nodulation in a reference agroecosystem. This multi-local field experiment, realized in the agroecosystem of Chlef in northern Algeria, involved 24 sites where the local well-adapted genotype Ain temouchent is grown. Determination of soil properties allowed the identification of three clusters of sites. Plant biomass (SDW) varied significantly among sites from 6.7 to 39.4 g SDW plant -1 and was highly correlated with nodule biomass (NDW). The slope of the regression function between NDW and SDW, defined as the efficiency in use of the rhizobial symbiosis (EURS) inside clusters ranged from 67 to 200 g SDW g-1 NDW. Analysis of the EURS highlighted the existence of a low nodulation threshold of 0.1 g NDW plant-1 below which the contribution of nodulation to the host plant growth was not significant and a high threshold above which the nodule biomass increase was not linked with an increase in shoot biomass. Thus, the significant regression of shoot growth as a function of nodulation ranged from 0.10 to 0.35 g NDW plant-1 (R 2 = 0.54, P < 0.001). Moreover, nodule biomass was positively correlated with soil Olsen-P, more particularly in cluster A (R 2 = 0.50, P < 0.05) and B (R 2 = 0.61, P < 0.01). This approach proved to be a rapid and efficient way to identify the major factors affecting nodulation in order to develop strategies to optimize nodule contribution to chickpea growth and yield.
  • Kirje
    Study of influence of heat stress on some physiological and productive traits in Holstein-Friesian dairy cows
    (2021) Penev, T.; Dimov, D.; Marinov, I.; Angelova, T.
    The aim of the research was to study the effect of heat stress (HS) on some physiological and productive traits in Holstein-Friesian dairy cows. The study included 22 cows on different parities. In the building where the cows were housed, the temperature-humidity index (THI) was reported at 10:00 and 15:00 h, at the same time the rectal temperature (RT) and respiratory rate (RR) were reported for each of the examined cows. The daily rumen activity was taken from the SCR system by Allflex. The average THI values in May were 71, in June - 75, in July - 74, and in August - 77, from which it follows that in the summer months the cows were in conditions of mild to moderate heat stress throughout the day. The average daily milk yield of the cows increased from May to June and reached 41.44 kg day-1 , then decreased in July and August to 37.2 and 32.48 kg day-1 , respectively. With an increase in the THI values, an increase in the RR and RT was registered, as in THI above 79 the RR was 56.54 per min, and the RT was 39.33 °C. With increasing the THI values, the rumination of the cows decreased from 563 per day at THI < 72 to 542.5 at THI > 79. In cows with high daily milk yield, a higher RT was registered, and in cows with more than 50 kg per day, the RT was 39.09 °С. A more intense rumination was found in cows with higher daily milk yield. In cows with an average daily milk yield of 33.26 kg, an average of 450 ruminations per day were reported, and in those with an average milk yield of up to 42.89 kg - 650 ruminations per day. From the research conducted it was found that the studied physiological traits - rectal temperature, respiration rate and rumination are influenced by HS and the intensity of this effect depend on the daily milk yield of cows and THI levels.
  • Kirje
    Biochemical contents of highbush blueberry fruits grown in the Western Forest-Steppe of Ukraine
    (2021) Shevchuk, L.M.; Grynyk, I.V.; Levchuk, L.M; Yareshcenko, O.M.; Tereshcenko, Ya.Yu.; Babenko, S.M.
    The study of the physical and consumption qualitative indices of the highbush blueberries (the cultivars ‘Reca’, ‘Elizabeth’ and ‘Bluegold’) in the Western Lisosteppe of Ukraine has shown that the biggest fruit mass was accumulated by the berries of two last mentioned vs (1.54–1.50 g respectively). ‘Bluegold’ has this indicator as the least variable (V = 10.6%). The accumulation of fruit mass of all studied cultivars was facilitated by a moderately humid period of their development in 2018 with a hydrothermal coefficient of 1.1–1.2. The favorable year for the intensive synthesis of the dry matter and soluble solids was 2017 when the precipitation amount did not exceed 44 mm. The biggest number of the mentioned substances during the research period was accumulated by fruits of ‘Reca’ - 17.48 and 13.24%, respectively. It was established that the dry matter content had high level of stability (V = 8.2%), and middle was for soluble solids (V = 19.5%). The amount of monosaccharides from which glucose and fructose were investigated in fruits varied from 6.11 (‘Bluegold’) to 7.85 (‘Reca’), it was slightly lower in ‘Elizabeth’ berries - 7.78%. ‘Bluegold’ fruits were characterized by high stability (B = 9.6%) of the biggest content of titrated acids among the studied cultivars (2.42%). The dry weather with low number of precipitation in 2017 (hydrothermal coefficient 0.3–0.4) was favourable for the accumulation of both the mentioned acids and vitamin C in fruits of highbush blueberries in the period of their formation and growth. The amount of ascorbic acid in fruits in the specified year varied from 20.00 mg 100 g -1 WM (‘Reca’) to 27.00 mg 100 g -1 WM (‘Elizabeth’) with an intermediate value of 22.50 mg 100 g -1 WM (‘Bluegold’). The latest of the mentioned varieties had the most constant index (V = 7.0%). The content of polyphenolic substances was slightly dependent on weather conditions during the period of fruit growth, the coefficients of variation were 6.2% (‘Reca’), 7.0% (‘Elizabeth’) and 5.8% (‘Bluegold’). The fruits of the last mentioned cultivars were characterized with the biggest anthocyanins and chalcones content (68 and 13 mg 100 g -1 WM, respectively). The substantial indirect dependence of the content of the nutritive substances and anthocyanins on the berry mass was revealed in the ‘Reca’ fruits.
  • Kirje
    Comprehensive study on wheat flour quality attributes as influence by different agrotechnical factors
    (2021) Magyar, Z.; Pepó, P.; Gyimes, E.
    The present polyfactorial long-term experiment was conducted to determine the role of different agrotechnical factors, like fertilization, forecrop, year and cultivar on the quality and yield attributes of a classical and a modern winter wheat genotypes. The research gives a complex view of the alteration of the most quality parameters (32) that are rarely done together in a single experiment (n = 96). All the studied factors had a significant effect on some tested properties. First growing season with fair water supply was beneficial for yield (+21.7%) however, the 2nd one with mild weather in spring and average annual precipitation was favourable for quality parameters (HFN: +3%, GI: +19%, GS: -51%, DDT: +22.4%, ST: +24.6%, DS: -14%, PDR: +37.6%, PD: +6%, PMR: +51.5%, PE: +52.7%, W: +25.8%, LV: +16.3%, HI: +13.3%). The optimal fertilizer demand of the different parameters varied to realize the potential of the varieties (N90P68K80 for Y, VWA, PWA, PMR, PE, LV, Mavg, KW and HI; meanwhile N150P113K133 for CP, WGC, ZI, VQN, ST, W and P/L). In the case of suboptimal nutrient supply, the effect of fore crops was significant (Y, CP, DGC, ZI, FE, VQN, DDT, ST, DS, PDR, PMR, PE, Mavg and all alveographic values). Comparing the varieties, GK Öthalom had better fertilizer response attribute (NUECP) and quality parameters, till then Mv Ispán possessed significantly better natural nutrient utilizing property (+22.9%), NUEY and yield (+31.7% in 2019). Summarizing the results, there is a need to put great emphasis on the selection of adapted cultivar and variety-specific agrotechnology practices, also these data contribute to a better understanding of the relationships between the quality parameters.
  • Kirje
    Copper modulates the biochemical and enzymatic activity and growth of tomato cultivars grown in vitro
    (2021) Comar, C.G.; Queiroz, M. dos S.; Andrade, M.M. de; Trettel, J.R.; Magalhães, H.M.
    Copper (Cu) is a micronutrient that is neglected for tomato growth. This study sought to identify the effects of exposure to Cu on the growth and biochemical activity of two tomato cultivars. Tomato seeds of ‘Carolina’ and ‘Cereja’ cultivars were disinfected and inoculated in MS medium plus copper sulfate concentrations (CuSO4) (default MS, 25, 50, and 100 µm) and had their growth monitored for 30 days. It was estimated that the growth and biomass accumulation of tomato plants ‘Carolina’ and ‘Cereja’, both from the aerial part and the roots, were benefited by 25 e 50 µm of CuSO4. However, it was observed that these concentrations were inefficient in controlling hyperhydricity and leaf deformation. There was a reduction of these phenomena in the treatment with 100 µm, in both cultivars. Tomato of ‘Carolina’ cultivar subjected to 100 µm showed an increase in anthocyanins and superoxide dismutase (SOD) activity in the root system. There was a reduction of catalase (CAT) activity in shoots exposed to Cu. ‘Cereja’ tomatoes subjected to 100 µm showed an increase in CAT and SOD activity in shoots and roots, respectively. It was concluded that the ‘Carolina’ and ‘Cereja’ tomatoes have their growth impaired when exposed to 100 µm CuSO4. Concentrations higher than 50 µm of CuSO4 cause an increase in the antioxidant activity in the shoot of tomato plants from the ‘Carolina’ cultivar. Concentrations higher than 50 µm CuSO4 increase SOD activity in the root system of tomato plants from the ‘Cereja’ cultivar.
  • Kirje
    The effect of synbiotic inulin and enterococcus bacteria on digestive health and weight gain in calves
    (2021) Arne, A.; Ilgaza, A.
    The aim of study was to investigate the effect of a synbiotic containing Enterococcus bacteria and 3 different concentrations of inulin on the performance and health status of calves. Forty randomly selected healthy male Holstein crossbreed calves 23 (+/- 5) days old and weighing 50 kg (+/- 5 kg) were randomly allocated to 4 groups: control group (CoG n = 10) fed only whole milk, and 3 synbiotic supplemented groups: 1) SynG6 n = 10, 2) SynG12 n = 10, 3) SynG24 n = 10, in which calves received various amounts of prebiotic inulin (artichoke powder 6 g, 12 g, and 24 g) with 0.25 g of the probiotic Enterococcus faecium (2×10 9 CFU g -1 ). At the end of this study all three synbiotic group weight gains were significantly greater than the control group (p < 0.01). SynG12 (12 g artichoke powder) group's weight gain was significantly greater than control and the 6g and 24 g synbiotic groups (p < 0.05). The average cold carcass weight results were similar to the live weight results: SynG12 was significantly (p < 0.05) higher than SynG6 and SynG24. Supplementing feedings with this combination of the synbiotic containing 6 g of inulin (produce in Latvia) mixed with Enterococcus (Protexin, UK) bacteria (SynG12) was most effective in achieving the greatest daily weight gain and cold carcass weight.
  • Kirje
    Morphological and morphometric characteristics of Cornelian Сherry (Cornus mas L.) in natural conditions of the Crimean Peninsula
    (2021) Kashirina, N.A.; Bagrikova, N.A.; Zhaldak, S.N.; Pashtetsky, V.S.; Drobotova, E.N.
    Cornelian cherry (Cornus mas L.) is a valuable fruit and ornamental plant in the Cornaceae family. This is a promising frost- and drought-resistant crop, undemanding to growing conditions. Fruits and leaves of plants are rich with biologically active substances which allows them to be used in pharmaceutical, food, liquor, and other industries. In the natural non-cultivated communities on the Crimean Peninsula the species is represented by a wide variety of forms that are promising for study from the point of view of botanical and breeding research. There is practically no information in the scientific literature about the characteristics of cornelian cherry for the most common places of its growth on the Crimean Peninsula, regarding the morphobiological features and patterns of development of cornelian cherry plants, which determines the relevance of research. The purpose of this work was to study the intraspecific variability of cornelian cherry plants within natural coenopopulations under varying ecological conditions in the foothill, mountain, and South Coast of the Crimea in order to identify the most promising forms for further breeding research. The results of a three-year study (2017 to 2019) revealed differences in the life form of plants, in the timing of fruit maturation, in the shape and color of the leaf and fruit, and in their metric parameters. Promising forms of plants with the largest fruits (an average weight from 1.65 g to 1.81 g) and a low percentage of endocarp - from 10% to15% (Form 1 - CP I, CP II, CP V, Form 2 a - CP IV) can be recommended for further breeding research.
  • Kirje
    Characterization of different wood species as potential feedstocks for gasification
    (2021) Sulg, Mari; Konist, Alar; Järvik, Oliver
    This paper provides an extended overview of the chemical characteristics of 19 different wood species originating from Estonia. The variation of chemical composition in wood and bark was investigated using a variety of analytical techniques including WD-XRF, ICP-MS, and elemental analysis. Principal component analysis (PCA) was used to observe clustering in the sample set. It revealed a clear data clustering in terms of the wood and bark samples. Wood characteristics exhibit quite narrow ranges, on the other hand the composition of wood bark samples is significantly different and more distributed. The correlations and associations among 27 chemical parameters, including 16 ash-forming elements, were studied. Several significant positive correlations between Cr-Ni-Fe, Ca-Sr, Al-Na-Si-Ti, K-Mg-P, Fe-Zn-Cr-Ni-Cu, Ash-Ca, N-S-P and O-volatile matter were found. Most of the metallic components are negatively correlated with volatile matter, C, H, O and heating value and are positively related to each other, or no significant correlation was identified. Results are compared to literature data and technical quality standards for biomass. Biomass feedstocks availability and composition for gasification process was discussed. Wood samples had higher volatiles content than in bark which is an indication that higher conversion rate and lower gasification temperature can be used. Spruce, pine and black alder barks have higher fixed carbon content than other common species that may increase biochar yield. Commonly available woods like Scots pine, Norway spruce, aspen, birch, black alder and grey alder may considered as suitable feedstocks for gasification because of their low N, S, Cl, and ash content together with high volatile matter, however, relatively high total heavy metals content were found from birch and grey alder barks compared to other hardwoods.
  • Kirje
    Matrix quality variability of oilseed radish (Raphanus sativus L. var. oleiformis Pers.) and features of its formation in technologically different construction of its agrophytocenosis
    (2021) Tsytsiura, Ya.H.
    Overview of the formation of matrix variability of oilseed radish seeds at two levels: within a single pod and within the generative part of the plant, given the presence of vertical layering in the placement of fruit elements. The peculiarities of formation of variation component of morphological parameters of seeds from different zones of inflorescence were estimated, basing on their electrical scanning for oilseed radish agrophytoconosises of different technological construction and sowing rate against the background of four options of mineral nutrition (without fertilizer to the level 90 kg ha-1 with an equal interval of 30 kg ha-1 of the primary material). The results of the value of matrix variability in morphological and weight characteristics were grounded on the basis of the analysis of the structure of selected seed fractions and their intra-group variation. The main features of formation of morphometric variability of seeds from different zones of inflorescence depending on different technological construction were formulated.
  • Kirje
    Anatomical traits and structural components of peduncle associated with lodging in Avena sativa L.
    (2021) Silveira, D.C.; Pelissoni, M.; Buzatto, C.R.; Scheffer-Basso, S.M.; Ebone, L.A.; Machado, J.M.; Lângaro, N.C.
    Lodging dramatically reduces the yield of cereals and increases the difficulty of mechanical harvesting. Because it is a complex phenomenon, new cultivars with genetic resistance to lodging is a sustainable alternative in agricultural production systems. This resistance is associated with a combination of factors, such as stem thickness and stiffness, being closely linked to anatomical traits and structural carbohydrates present in the stem. In the present study we compared, under field conditions, eight contrasting oat cultivars in terms of lodging resistance. Our aim in this study was to investigate the association of anatomical traits and structural components of the peduncle with resistance to lodging, aiming to assist in the plant selection process. In addition, a second objective was to understand the genetic dissimilarity among oat cultivars according to the characters studied. Some characteristics for potential indirect selection were studied in this work and if correlated with lodging can be used to identify superior genotypes. From the anatomical point of view, the correlation obtained between the internal vascular bundle and the lodging resistance factor allowed us to confirm that this trait can be used in indirect selection to lodging resistance. The structural components of peduncle, in the two ways explored in the present study, comparison of mean and correlation, did not demonstrate the potential to be used exclusively as plant selection characters traits for lodging resistance. There is noticeable variability in oat cultivars for most stem traits.
  • Kirje
    Features of bird-cherry that inhibits the breeding of the population Rhopalosiphum padi (L.) (Hemiptera: Sternorrhyncha: Aphididae)
    (2021) Gandrabur, E.S.; Vereschagina, A.B.
    Long-term studies (2012–2018) of the formation of the Rhopalosiphum padi (L.) heteroecious population (number of remigrants, oviparae and eggs in autumn, number of perished eggs, fundatrices larvae, timing of flight of emigrants in spring) on the two samples of primary host Padus avium Mill. and P. avium x P. virginiana (L.) characterized by various morphophysiological features have been carried out. By the methods of mathematical statistics, it has been proved that this formation occurs under the significant influence of the year conditions (A), host plant characteristics (B) and these factors interaction (AB). The most visible was their highly significant impact on the number of wintering aphid eggs (A = 200.42; B = 142.6; AB = 25.612). Plant characteristics such as significantly larger leaf area from the middle part of the shoot on P. avium x P. virginiana, than on P. avium (t = 8.37; р0.01 = 2.85) was important for attracting remigrants and the prone buds on P. avium x P. virginiana - for oviposition and survival of eggs. Correlation between the period of leaf fall and number of aphid eggs on both bird-cherry samples is presented. The effect of weather conditions on R. padi and primary hosts relationships is discussed. Correlation (r = 0.76; p = 0.0048) between average temperature of October and eggs number on P. avium is given. R. fundatrices.
  • Kirje
    Effects of retained fetal membranes treatments and dry period length on the subsequent lactation in cows - milk yield and somatic cell count
    (2021) Skuja, S.; Antāne, V.; Lūsis, I.
    Different treatment strategies in cows with retained fetal membranes (RFM) may affect subsequent lactation in various ways. Also, excessively short or long dry periods (DP) can decrease milk yield (MY), increase the risk of poor udder health, and increase the risk of RFM. This study aimed to evaluate how different treatment strategies of RFM affect subsequent lactation in cows, i.e., MY and udder health determined on the somatic cell count (SCC) bases in milk, expressed as somatic cell score (SCS). A secondary but equally important objective was to analyse the dry period length (DPL) effect on the subsequent lactation in cows. The cows from two herds were divided into three groups: group 1–healthy control; group 2–cows with RFM, removed manually and treated with intrauterine (IU) antibiotics (AB); group 3–cows with RFM, not removed, but treated IU with AB. The DP of cows was divided post factum into shortened (up to 46 days), traditional (47 to 70 days), or prolonged (over 70 days). Statistical analyses were performed using linear multiple regression and multivariate analyses. Differences were statistically significant when P <0.05. The effect of different RFM treatment strategies on MY and SCS was evaluated. There were no statistically significant effects of RFM treatments on the MY in the subsequent lactation. However, there was a tendency (P = 0.07) for SCS in standard lactation to be higher in cows in group 2. The highest economic losses, calculated from the decrease in MY, were detected in the same group. Significantly lower MY was observed in cows with a shortened DPL during the first 30 days PP (P <0.05). The DPL did not affect the SCS.
  • Kirje
    Dynamics of tuber weight in early potato varieties in the contrasting weather conditions of the Northwestern Russia
    (2021) Novikova, L.Yu.; Chalaya, N.A.; Sitnikov, M.N.; Gorlova, L.M.; Kiru, S.D.; Rogozina, E.V.
    Under climate changes, it is particularly important to search for characteristics of varieties that are steady in contrasting weather conditions. The aim of the present research was to study the relationship between the growth of tubers and haulms in early potato varieties in the Northwestern Russia. Fourteen early potato varieties were studied in the field experiments conducted in 2017–2019 in the vicinities of St. Petersburg. The results of three intermediate digs on the 45th, 60th and 75th day from the planting date were analyzed. The correlation analysis, ANOVA, and regression were used. The average haulm and tubers weight significantly differed in the years of the study, while the number of tubers per plant and the haulm to tubers weight ratio did not differ. The relative growth rate of tubers weight from day 45 to 60 and from 60 to 75 did not differ significantly between 2018 and 2019, the years contrasting in terms of weather conditions. On the average, the tubers weight increased 2.6–2.8 times from day 45 to 60, and 1.4 times from day 60 to 75. It has been established that the early prediction of productivity in early potato varieties can be based on the haulm weight on the 60th day after planting; its coefficient of correlation with productivity was 0.72–0.79. Every 100 grams of the haulm weight on day 60 ensures a 100–200 g increment in the tubers weight by the time of harvest on day 80. The obtained results can be used in the development of a morphometric indicator-based automated system for monitoring the growth of potato plants.
  • Kirje
    Use of soil enzyme activity in assessing the effect of No-Till in the South of Russia
    (2021) Mokrikov, G.; Minnikova, T.; Kazeev, K.; Kolesnikov, S.
    The activity of 11 enzymes (catalase, dehydrogenases, peroxydases, polyphenoloxidases, ascorbateoxidase, ferrireductase, β-fructofuranosidase, amylase, urease, phosphatase and protease) was assessed under conditions of steppe zone in the south of Russia when using different tillages. Winter wheat and sunflower are main crops in these soils. Moreover, chickpea, coriander, lint, barley, corn and some other crop are cultivated here in the crop rotation duration 6 years. Enzyme activity was compared in soils of 15 fields with long-term no-till (NT) versus to 15 fields with conventional tillage (CT). The researches were held along the whole Haplic Chernozem Loamic at a depth of 0–65 cm. Special attention was paid to top soil (0–10 cm), which is directly subject to the mechanical effect. The carbon cycle enzyme (β-fructofuranosidase) activity was the most sensitive indication for NT use. In top soil the enzyme activity was greater by 16–35% at NT versus to СТ. Activity of this enzyme reduces by 28–293% when soil depth increasing in both the tillages. Enzymes of different classes had different behaviours in soils depending on season, crops and tillage thanks to biochemical nature. Hydrolases and oxidoreductases were assessed by the indices characterizing soil condition and health. For this purpose geometric mean by hydrolase activity (GMEhd) and geometric mean by oxidoreductase (GMEox), as well as integral index of biological soil condition (IIBC) were used. Index GMEox in soil under sunflower reduced by 16% in summer versus to spring. Thereby, hydrolase index GMEhd reduced by 60%. At NT activity of oxidoreductase was lower by 10 and 13%, and activity of hydrolase was increased by 12 and 14% versus to СТ. Soil IIBS values at NT increased by 18–35% at average within three years (2016–2018). The use of NT technology contributes to an increase in the activity of hydrolases and soil quality due to the conservation of moisture in the soil.
  • Kirje
    Experimental research into new harrowing unit based on gantry agricultural implement carrier
    (2021) Kuvachоv, V.; Bulgakov, V.; Adamchuk, V.; Kaminskiy, V.; Melnik, V.; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
    From the point of view of energy saving, research into agricultural gantry units equipped with new implements specially adapted for operation in such systems and capable of efficiently functioning in controlled traffic (permanent lane) and wide span (gantry) systems is an important and topical issue in soil tillage science. The range of wide span systems includes harrowing units for fallow land tillage. This paper describes the experimental determination of the operating characteristics of the harrowing unit, in which a gantry implement carrier propels harrows for fallow land tillage, for the purpose of establishing the compliance of their parameters with the fundamental principles of the effective implementation of the controlled traffic and wide span soil management. The experimental investigations were done using strain-gauge and control-and-measuring equipment with analogue-to-digital conversion of the signals received from the sensing elements. An agricultural wide span unit with a track width of 3.5 m and harrows for fallow land tillage were investigated. The results show the harrowing unit is well adapted to operation in controlled traffic and wide span soil tillage systems and delivers high quality performance of the harrowing process. The latter effect is also due to the fact that the gantry travels on the compacted tracks which have a few surface irregularities compared to cultivated soil. The coefficient of variation of the draught force applied to the hook of the gantry during harrowing operations did not exceed 10%. This is evidence of the high stability (low variability) of the harrowing process, which has a positive effect on the motion stability of the harrowing unit based on the gantry tractor.