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2021, Vol. 32, No. 1

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  • Kirje
    Potato yield forecast by using guttation test method in household laboratory conditions
    (Estonian Academic Agricultural Society, 2021) Nugis, Edvin; Kuht, Jaan; Komarov, Аleksei; Estonian University of Life Sciences
    This paper aims to present the use of the guttation test method to establish the relationship between guttation and potato (Solanum tuberosum L.) yield. The laboratory tests (in vitro L.) under household conditions were carried out. To assess the state of the potato (variety 'Ando') yield the field (0.07 ha) of the family farm "Miili" were used. Assessment of the state of guttation plant barley (Hordeum vulgaris L.) variety 'Anni' by using of hydro-thermostat in conditions adapted hose hold laboratory (according to the generally known a bad epidemiological situation) were carried out. The test sites were located on a light sandy loam of Molli-Calcaric Cambisol (WRB) with areas of the field in the presence of soil samples No. 1 and 2. We have found that the maximum yield of potato 'Ando' on a plot of soil sample No. 1 (15 900 kg ha–1 or 1.00 of relative units) was obtained. At the same time, the minimum yield of soil sample No. 2 of the potato tubers was 3900 kg ha–1 (0.25 of relative units). To ranking score of the soil fertility level of the studied potato field, additional laboratory experiments were carried out, with extremely humus-rich soil (the guttation droplet imprint on the filter paper was 117.6 mm2 to that was equated to 1.00 of relative units) and with sand the guttation droplet imprint – 37.0 mm2 and 0.31 of relative units, respectively. The results of laboratory tests by using of guttation method with barley (variety 'Anni') carried out. The soil samples have been taken from the same areas of the field. In this case, for soil sample No. 1 the average area of the guttation droplet imprint on the filter paper was 55.1 mm2 to that was equated to 0.47 of relative units and for soil sample No. 2 – 42.9 mm2 or 0.36 of relative units, respectively. The results of the research have shown that concerning cultivating potatoes (variety 'Ando') and guttation experiments with barley (variety 'Anni') under conditions of soil samples No. 1 and 2 of the potato field a quite reliable relationship between guttation and the yield of potato tubers (P <0.001, R2 = 0.98) was obtained. To assess the different levels of soil fertility for soil samples No. 1 and 2 in the potato field taking as a reference soil with the highest possible fertility (humus-rich soil) and with the lowest possible fertility (clean sand) it was revealed that guttation of soil sample No. 1 of the potato field was 1.6 times inferior according to the results of guttation of the humus-rich soil. Analytical calculations have shown that if we are dealing with a humus-rich soil where potato 'Ando' cultivation would be carried out under the conditions of classical organic farming then the yield of potato tubers would be 22 880 kg ha–1 or 30 Mg ha–1 rounded. The novelty of our research was the development of a method for assessing the yield of potato by using the guttation test method.
  • Kirje
    Research into the parameters of a potato harvester's potato heap distributor, and the justification of those parameters
    (Estonian Academic Agricultural Society, 2021) Olt, Jüri; Adamchuk, Valerii; Korniushyn, Viktor; Melnik, Viktor; Kaletnik, Hryhoriy; Ihnatiev, Yevhen; Ilves, Risto; Estonian University of Life Sciences. Institute of Technology
    The low levels of efficiency and general quality when it comes to the use of potato harvesters in difficult soil and climatic conditions substantiate the relevance of the problem which is faced in terms of research by technologically advanced equipment and tools. They are looking to increase the efficiency of potato harvesters. This paper serves to justify the formation of the design and technical parameters of the V-type distributor, which directly acts on the undermined mass to increase the ability of the potato harvester to separate the soil. Preliminary experimental studies have shown that to achieve efficient technological processing in terms of the distribution of the general soil and potato heap, the distributor must possess the appropriate technological and design parameters. Calculations which have been carried out by using as a basis the theoretical dependencies that have been obtained serve to allow us to determine the optimum speed of progress through the heap, using the following design and kinematic parameters: Vel = 2.0 m s–1, А = 0.35 m, hv = 0.22 m, Δ = 0.08 m, bel = 1.2 m. The allowable speed for heap movement will be [V] = 1.62 m s–1, which will ensure the prevention of any heap clogging in front of the distributor. An analysis of the dependencies which have been obtained during the work shows that rational values for the distributor wing’s fitting angle fall within the range of α = 40°.
  • Kirje
    The impact of nutrition optimization on crop yield and grain quality of spring barley varieties (Hordeum vulgare L.)
    (Estonian Academic Agricultural Society, 2021) Panfilova, Antonina; Gamayunova, Valentina; Potryvaieva, Natalia
    The research is aimed to determine the yield and quality of spring barley grain depending on the varietal characteristics and optimization of nutrition. Methods. The experimental studies were conducted during 2013–2018. on the research field of Mykolayiv National Agrarian University (Ukraine). Results. The highest grain yield of spring barley varieties in all years of research is determined to be formed by growing the crop on the background of applying N30P30 and carrying out two foliar top dressing of crops with Escort-Bio or Organic D2 preparations. So, on average, over the years of research on the variety factor, the grain yield was 3.41 and 3.37 t ha–1, which exceeded its level in the non – fertilized control by 26.7–28.2%. The optimization of nutrition affected the grain quality indicators of the studied varieties of spring barley significantly as the maximum values of grain nature (606.2 up to 611.2 g l–1, depending on the variety) were reached by applying N30P30 before sowing and double applying of Escort-bio to the crops. The protein content in the grain and digested protein in this nutrition option was also determined to be the maximum as 12.5 up to 13.1% and 61.0 up to 63.8 g kg–1, respectively, depending on the variety. Slightly higher grain quality indicators among the spring barley varieties taken for the study were formed by the 'Aeneas' variety. The highest protein content in the spring barley grain of 'Stalker' and 'Vakula' varieties was accumulated in 2018, and the last one was in 2016. The amount of protein in both varieties increased under the influence of nutrition optimization and, on average, it increased from 10.8% in the control up to 11.3–11.6% in the variants with fertilizing in ‘Stalker’ variety and from 10.7 up to 11.3–11.6% in 'Vakula' variety during three years.
  • Kirje
    Antifungal assessment of plant extracts, biocontrol agents and fungicides against Fusarium verticillioides (Sacc.) causing ear rot of maize
    (Estonian Academic Agricultural Society, 2021) Subedi, Subash; Neupane, Saraswati
    Ear rot is a prominent biotic threat of maize causing significant yield loss and poor quality of grains. The antifungal activity of aqueous extract of Acorus calamus L., Xanthoxylum armatum DC., Azadirachta indica A. Juss., Lantana camera L. and Artemisia indica Willd at three different concentrations (1, 2 and 3% W/V), four chemical fungicides viz., Dithane M-45 (Mancozeb 75% WP), SAAF (Carbendazim 12% + Mancozeb 63% WP), ACME-COP (Copper oxychloride 50% WP) and Bavistin (Carbendazim 50% WP) at (500, 1000 and 1500 ppm) and three biocontrol agents (BCA) namely Trichoderma viride, Trichoderma harzianum and Trichoderma koningii were investigated against Fusarium verticilliodes (Sacc.) causing ear rot of maize. The experiment was carried out by poisoned food and dual culture techniques in a completely randomized design with five replications under laboratory conditions at National Maize Research Program, Rampur, Chitwan during the summer season of 2019. F. verticillioides showed significant growth inhibition in all the treatments compared to control. The A. calamus even at a lower dose (1% W/V on PDA) was able to check completely the growth of pathogen (4.00 mm). The mycelial growth inhibition per cent of A. calamus, L. camera, X. armatum, A. indica, and Artemisia indica at 3% W/V was 95.50, 51.13, 45.50, 42.12 and 35.36% respectively. In the case of fungicides, at 1500 ppm, the maximum antifungal potential was observed with SAAF (86.32%) followed by Dithane M-45 (80.27%), Bavistin (64.80%) and ACME-COP (59.42%). Antagonist Trichoderma viride completely overgrows F. verticillioides and covers the entire medium surface and exhibit more than 60% inhibition on the 7th day of incubation. The antifungal components from these plant extracts, fungicides and antagonists explored in this study need to be tested further in field experiments to control the ear rot of maize.
  • Kirje
    Experimental research into operation of potato harvester with rotary tool
    (Estonian Academic Agricultural Society, 2021) Ihnatiev, Yevhen; Bulgakov, Volodymyr; Bonchik, Vitaliy; Ruzhylo, Zinoviy; Zaryshnyak, Anatoliy; Volskiy, Volodymyr; Melnik, Viktor; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
    The experimental research was carried out on a specially designed laboratory-and-field test unit with the use of a hydraulic vertical rotor drive and strain-gauge equipment mounted on a tractor as well as the set of interchangeable coupling pieces for setting the machine's operating duty. Research into the process of breaking two adjacent potato row beds with the vanes of a vertical rotor has been undertaken. A design and process schematic model has been proposed for the operation of the potato harvester. Experimental research into the geometrical parameters of the potato row has been carried out to select the design parameters of potato harvesters. Based on the results obtained during the experimental investigations, the rational ranges have been established for the work process of the rotary potato harvester, the methods of engineering clod breaking tools have been developed. Following the completion of the full factorial experiment, regression functions have been generated. Their analysis has proved that the following factors have the greatest impact on the optimisation parameters: the rotor diameter and the clearance between the rotor and the spherical discs. The following parameters have been optimised based on the response surface analysis: soil separation ratio S = 93.5%, tuber damage rate Pb = 0.97%, total power consumption by unit operation Nа = 18.27 kW, at the following pre-set values of the factors: nр = 77 min–1, Vm = 2.2 m∙s–1, dр = 0.825 m, l2 = 0.3 m. The maximum discrepancy between the results of the theoretical and experimental investigations for determining the design and process parameters of the potato harvester does not exceed 15%. The completed economic testing has proved the advantages of the experimental potato harvester as compared to the existing ones. That said, the separation ratio of the pilot machine is equal to S = 91.4%, which is 23% higher than in the reference case, while its tuber damage rate is equal to 1.14%, which is 5.0% better than in the reference case. The recommendations for the selection of the rational operation duty of the rotary potato harvester as well as the methods for the engineering analysis of the design and process parameters of clod breaking tools have been developed.
  • Kirje
    Genetic diversity analysis and DNA fingerprinting of tomato breeding lines using SSR markers
    (Estonian Academic Agricultural Society, 2021) Al-Shammari, Aziz Mahdi Abd; Hamdi, Ghassan Jaafar; Al-Mahdawi, Muthanna Abdulkhader Salh; Mohammed, Noora Khalifa
    There is a need to expand the information on genetic relationships between tomato (Solanum lycopersicum L.) lines to improve hybridization breeding. The genetic diversity and relationships among 24 tomato lines were evaluated by simple sequence repeat (SSR) markers. A total of 65 bands were generated with 15 SSR primers, of which 64 bands were polymorphic. The mean polymorphic information content was 0.356. There was a high degree of polymorphism between tomato cultivars. The mean marker index and heterozygosity were 0.045 and 0.454, respectively. Cluster analysis grouped cultivars into 6 main clusters. The cvs. Mo. H. P, 'C. C. Orange', and 'Marb' had the greatest genetic distance from other cultivars and is suitable for hybridization to achieve maximum variability for selection in segregating populations. The data can be used to select appropriate parents in tomato hybridization breeding.
  • Kirje
    Review: The influence of genotypic and phenotypic factors on the comfort and welfare rates of cows during the period of global climate changes
    (Estonian Academic Agricultural Society, 2021) Borshch, Oleksandr O.; Ruban, Serhii; Borshch, Oleksandr V.
    The study of the influence of weather phenomena on behavioural and physiological processes plays an important role in the development of highly effective methods of dairy farming management. Climate and weather factors have important signification in the system of interaction "organism-environment". One of the main factors of cows’ comfort improvement in different types of premises, on ground runs and pastures is the creation of such indicators of microclimate that would best meet the biological needs of dairy cows, depending on the season and productivity. Due to the constant metabolic processes, the body of cattle is very hurtable to ambient temperature. This is especially felt during periods of prolonged low or high-temperature shocks. Disorders of metabolic and thermoregulatory processes directly affect the duration and nature of behavioural and physiological reactions and cause stress in animals. Prolonged temperature stress is the reason for fluctuations in productivity, quality of milk and problems with reproduction and together significantly affect the profitability of production. To reduce the impact of temperature stress on the body of dairy cows, scientists have proposed management strategies during periods of high and low-temperature shock. These strategies are divided into genotypic: the selection of heat-resistant individuals of different breeds and phenotypic: the use of microclimate control methods and modernization of feeding management methods. The effect of temperature stress on the body of dairy cows can be minimized due to genotypic (breeding of heat-resistant breeds) and phenotypic factors (water irrigation systems, ventilation, and the use of shade shaded shelters in summer and insulation of side curtains in winter), or a combination thereof. The purpose of this article is to summarize existing knowledge about the effects of temperature stress on the health, productivity and comfort rates of cows and to discuss management strategies that would mitigate the effects of these factors.
  • Kirje
    Effect of surface drip irrigation and cultivars on physiological state and productivity of faba bean crop
    (Estonian Academic Agricultural Society, 2021) Ulyanych, Olena; Poltoretskyi, Serhii; Liubych, Vitalii; Yatsenko, Anatolii; Yatsenko, Viacheslav; Lazariev, Oleh; Kravchenko, Vitalii
    Lack of water is one of the main abiotic factors that affect the change of plant production processes by imposing certain morphological, physiological and biochemical changes. The aim of the research conducted in 2019–2020 was to study the change in the productivity and yield of green beans of different cultivars of Vicia faba L. var. Major and the formation of a symbiotic system on surface drip irrigation. The results of the biometric analysis showed that the cultivation of faba beans under irrigation contributes to an increasing in plant height by 4.7–12.2%, the number of branches per plant increased by 17.3–30.0%, the leaf area of faba bean crops increased by 21.2–24.9%. The content of total chlorophyll increasing by 16.9–40.5%. Antioxidant enzymes activity decreased depending on the cultivar Catalase activity by 10.6–22.5%, Guaiacol peroxidase – 19.4–25.9%, Superoxide dismutase – 19.3–24.4%. The yield of green faba beans (Vicia faba L.) increased by 31.3–39.2%. Growing faba beans on irrigation helped to reduce the protein content by 1.4–2.1 %, but to reduce the dry matter content by 1.3–2.0%, which was significant in both indicators. In general, drip irrigation contributed to the improved development of bean-rhizobial symbiosis of faba bean plants. The mass of the nodules on the drip irrigation increased by 0.3 g plant–1 regardless of the cultivar, and their number is 1.5–9.0 pcs plant–1 . The presented results give an idea of the functioning of the legume agrocenosis and the impact of irrigation on the main quality indicators of the product. Further research is to study the regimes (rates, timing, and multiplicity) of irrigation.
  • Kirje
    Factors of increasing alfalfa yield capacity under conditions of the Forest-Steppe
    (Estonian Academic Agricultural Society, 2021) Kvitko, Maksym; Getman, Nadiia; Butenko, Andrii; Demydas, Grygory; Moisiienko, Vira; Stotska, Svitlana; Burko, Lesya; Onychko, Viktor
    It was found that southern ecotype alfalfa (Medicago sativa) of variety 'Angelica' adapted to the soil and climatic conditions of the Forest-Steppe and was not inferior in yielding capacity to variety 'Rosana' which provided maximum indices in the phase of the beginning of budding at sowing rates of 6.0 million pcs ha–1 and ordinary row sowing method with row spacing 12.5 cm. It was discovered that with the increase of alfalfa sowing rate from 4.0 to 8.0 million ha–1 the dry matter content of varieties increased by 0.11–0.20% for sowing with row spacing of 25.0 cm. compared to row spacing of 12.5 cm. (22.62–22.83%). The average crude protein content in variety 'Rosana' was 20.68–21.37 and 'Angelica' 20.67–21.07%. Narrowing of row spacing contributed to an increase in crude protein content by 0.55–0.58%. The highest content NDF and ADF were observed in the second year of alfalfa grass life, respectively 30.72– 34.91 and 23.02–24.60%. During the third year of alfalfa grass usage, the indices decreased to 27.09–33.03 and 19.53–24.18%, respectively. Thus, during three years of life at different geographical origins, alfalfa in the phase of budding provided a stable dry matter output of 27.45–27.81 and crude protein output of 5.86–5.87 t ha–1 for sowing with row spacing of 12.5 cm. and sowing rate of 6.0 million pcs ha–1.
  • Kirje
    Bottle gourd (Lagenaria siceraria L.) crop response to different planting densities under both drip and widespaced furrow irrigation methods
    (Estonian Academic Agricultural Society, 2021) Mubarak, Ibrahim; Janat, Mussaddak
    Although bottle gourd (Lagenaria siceraria L.) is an important vegetable crop in rural communities in the arid Mediterranean region, still no sufficient information regarding its cultivation practices is available. A two-year field experiment (2019 and 2020) was carried out to assess the effects of planting density and irrigation method on bottle gourd yield, following a split-plot experimental design with two planting densities of about 11 111 and 5555 plant ha–1 , and two irrigation methods (drip irrigation and wide-spaced furrows as surface irrigation), with three replicates. Significant effects of both factors on bottle gourd fruit characteristics, dry matter, fresh marketable yield, water productivity (WP), and irrigation water use efficiency (IWUE) were found. Seasonal evapotranspiration and irrigation water amounts were considerably reduced by about 20% under drip irrigation as compared with surface irrigation. Moreover, dry matter, fresh marketable yield, WP, and IWUE were doubled. Combining drip irrigation with the lower planting density was the most favourable practice for the bottle gourd crop productivity under the studied context. These findings of high fresh marketable yield and water productivity suggest that bottle gourd crop could be considered as an alternative crop for food security and economic prosperity of rural communities. Adopting drip irrigation can effectively address the water shortage issue and sustain crop production in the arid Mediterranean area.
  • Kirje
    Rähkmuldade seisund ja levik Eesti põllumajandus- ning metsamaastikes
    (Estonian Academic Agricultural Society, 2021) Kõlli, Raimo; Tõnutare, Tõnu; Eesti Maaülikool. Põllumajandus ja keskkonnainstituut. Mullateaduse õppetool
    In the overview nomenclature, properties, distribution, productivity and usage of ryhky soils, as the Year 2021 Soil of Estonia, are treated. As synonyms of the name ryhky soils, also the names pebble rendzina and gravelly soils have been used in Estonian Soil Classification (ESC). In overview, the main attention is paid to dry, fresh and moist rich in coarse calcareous material mild-humuous (mull-type) soils. After WRB these soils may be characterized by prefix qualifiers as calcaric or eutric, skeletic or hyperskeletic and rendzic or mollic CAMBISOLS, LITHOSOLS or REGOSOLS, whereas all of them have endogleyic versions as well. The wet and eroded ryhky soils have been excluded from the overview as their properties depend not so on the coarse calcareous earth content as on feeding their soil water or water erosion. The area of ryhky soils forms 6.3% from whole Estonian soil cover and 11.1% from the arable land. The main criteria of ryhky soil species' determination are calcareousness, content and shape of coarse soil fragments, and water regime of soil cover. By ESC six soil species have been determined, from which three ones have endogleyic character. The fine earth texture of ryhky soils is mainly loam. From the coarse fractions, the indicative role belongs to the small stones (ryhk, pebble and shingle). The morphology, humus status and suitability of ryhky soils for management are treated on the level of soil species independence of land use (arable, forest or grassland).
  • Kirje
    Efficacy and selectivity of PRE-em herbicide on dependence of soil types and precipitation in sunflower crop
    (Estonian Academic Agricultural Society, 2021) Pacanoski, Zvonko; Mehmeti, Arben
    During the growing seasons in 2018 and 2019, two field trials were conducted to estimate how precipitation affects the efficacy of PRE-em herbicides in sunflower crop grown on different soil types. Both regions were naturally infested with a high population of Polygonum aviculare L., Solanum nigrum L., Chenopodium album L., Amaranthus retroflexus L., Portulaca olearacea L. and Echinochloa crus-galli (L.) P. Beauv. Efficacy of PRE-em herbicides varied among weed species, treatments, periods of efficacy estimation, regions and years, respectively. Overall performances of the PRE-em herbicides were correlated with the weather and soil properties. Humid April in Bitola region in 2018, particularly the first week after application (34 mm) before weed emergence caused herbicide leaching from the soil surface, which probably was the most likely reason for the lower efficacy of PRE-em herbicides in 2018, compared to their application in 2019. In 2018 precipitation above 30 years average were recorded in the Titov Veles region as well, but due to their equal occurrence particularly during the first and second week after application, as well as soil type properties (higher content of clay and organic matter) leaching did not occur and efficacy was good to excellent. Contrary, the limited precipitation after PRE-em application (five, nine, and eight mm during the first week before application, first and second week after application) may have contributed to the poor performance of PRE-em herbicides in the Titov Veles region in 2019 compared with 2018. Heavy precipitation directly following PRE-em application caused sunflower injury in the Bitola region in 2018, which ranged from 9–28% across PRE-em treatments seven days after application. Injures of oxyfluorfen and dimethenamid were more serious (24 and 28%, respectively). Sunflower yields for each treatment in both region s generally reflected overall weed control and crop injury.
  • Kirje
    Body condition effects on dry matter intake and metabolic status during the transition period in Holstein dairy cows
    (Estonian Academic Agricultural Society, 2021) Karis, Priit; Jaakson, Hanno; Ling, Katri; Runin, Maksim; Henno, Merike; Waldmann, Andres; Ots, Meelis; Chair of Animal Nutrition, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences; Chair of Animal Breeding and Biotechnology, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences
    The objective was to evaluate dry matter intake, metabolite concentrations and milk production of cows with different dry period body condition score (BCS). In addition, to support these results with previously reported insulin resistance and adipose tissue mRNA data on the same cows. Multiparous Estonian Holstein cows (n = 42) were assigned to three experimental groups on the basis of BCS 28 days before expected calving (d –28) as follows: BCS ≤ 3.0 (2.25–3.00; thin (T), n = 14); BCS = 3.25–3.5 (optimal (O), n = 14); BCS ≥ 3.75 (3.75–4.50; over-conditioned (OC), n = 14). Blood samples were taken between d –21 and d 42 in relation to calving, milk production data were collected throughout lactation. The OC cows' adaptation to the demands of lactation was the worst based on the comparison of dynamics of blood parameters between BCS groups. They had the most unbalanced metabolism and used more stored lipids compared to T and O cows. Fatty acids concentrations in the first week of lactation, related to insulin resistance status in the dry period and DMI in the first days of lactation, describe most of the variation (R2 = 0.55) in BCS loss during the first 42 days of lactation.
  • Kirje
    Response of onion growth and yield grown in soils of semi-arid regions to foliar application of iron under water stress conditions
    (Estonian Academic Agricultural Society, 2021) Gar, Laith Farhan; Bader, Basem Rahem; Al-Esawi, Jabbar Shihab Eyada; Abood, Mohammed Ali; Sallume, Mohammed Obed; Hamdi, Ghassan Jaafar
    Iron (Fe) is one of the major micronutrient crucial for plant growth, yield and quality. A field experiment was conducted in Fallujah, Iraq during the autumn season in 2019 to study the effects of foliar appli-cation of iron and irrigation levels on growth characteristics and yield of onion (Allium cepa L.). A two-factorial experiment arranged as a rando-mized complete block design with three replications was conducted in loamy sand soil. The two factors were water stress (50, 75, and 100% con-sumptive use of water) and iron concentrations (0, 100 and 200 mg L–1). The results show a significant decrease in plant height, number of bulbs, total chlorophyll content, dry mass, iron content in the leaves, the average weight of bulbs and total yield of bulbs by reducing irrigation levels from 100 to 50% of the water supply. Application of iron by foliar spraying significantly increased most of the aforementioned traits. The interactions between iron and irrigation levels were significant in most of the measured traits. The interaction between 100% water supply and 100 mg L–1 of iron achieved the highest total yield value (4 332 Mg ha–1) while the combina-tion of 75% of water supply and 100 mg L–1 of iron gave the highest value of water use efficiency (84.7%).
  • Kirje
    In vitro shoot growth performances and responses of potato (Solanum tuberosum L.) 'Muhzoto' under different treatments and explant types
    (Estonian Academic Agricultural Society, 2021) Winarto, Budi; Cempaka, Intan Gilang; Jatuningtyas, Ratih Kurnia; Budisetyaningrum, Sri Catur; Hartoyo, Budi
    Finding optimal shoot growth performances under different treatments and revealing different growth responses of different explant types as main objectives were assessed in the research. Different treatments of 5 000; 8 000 and 11 000 lx in light intensities; 0, 25, 50, 75 and 100 ml l–1 in coconut water (CW) concentrations; culture media (CM) of Murashige and Skoog (MS) medium supplemented with 1.5 vitamin strength in the medium in combination with 100 mg l–1 myoinositol, 1 mg l–1 calcium pantothenate (CaP), and 0.1 mg l–1 gibberellic acid-3 (GA3) (CM-1); 200 mg l–1 myoinositol, 1 mg l–1 CaP dan 0.1 mg l–1 GA3 (CM-2); 1 mg l–1 CaP and 100 ml l–1 CW (CM-3); and MS medium supple-mented with 1.5 total vitamin strength in the medium (CM-4 as control) and shoot tip, first, second, third, fourth and fifth nodes as explant types were gradually tested in the research. Virus-free Solanum tuberosum L. 'Muhzoto' explants and MS medium containing 1.5 strength of vitamin were used as explant source and basic medium. Four experiments were arranged in a completely randomized design (CRD) with 6–9 replications. Maximal shoot growth performances indicated by shoot height, stem diameter, internode length, greener leaves per shoot, leaf length and width were established in explants incubated under 11 000 lx light intensity applied continuously. Adding different concentrations of CW could not improve the growth of shoots, but they induced high contamination. Though MS medium containing 1.5 vitamin strength with 200 mg l–1 myoinositol, 1 mg l–1 CaP and 0.1 mg l–1 GA3 slightly improved shoot growth, there was no significant difference compared to control. Exploring shoot growth responses derived from different types of explants revealed that the shoot tips, 1st and 2nd nodes regenerated high branched shoots with the higher length of internodus; while 3rd, 4th and 5th nodes stimulated low branched shoots with higher stem diameter and the number of leaves per shoot. The branched shoots were a serious problem in preparing high-quality regenerants for 'Muhzoto' explants and significantly overcome by choosing, selecting and applying the right time on subculturing of the 'Muhzoto' explants.
  • Kirje
    Chemotactic responses of sweet flag (Acorus calamus L.) root exudates and evaluation of inoculation effects on its growth
    (Estonian Academic Agricultural Society, 2021) Prakash, P.; Karthikeyan, Balathandayutham; Joe, Manoharan Melvin
    Root exudate is an important source of nutrients for microorganisms in the rhizosphere and it plays a major role in the early colonization including chemotactic responses and adsorption of rhizospheric bacteria. In this study, we characterized the root exudates from sweet flag under hydroponic conditions and assessed their effect on plant growth. In the present study, the crude root fractions of sweet flag recorded a maximum yield of 520.6 μg plant–1 followed by cationic, anionic and neutral fractions. Among the qualitative and quantitative analysis of different fractions, the cationic fraction recorded a maximum of 90 μg plant–1 for glutamic acid, followed by aspartic acid, glycine, serine and proline. In the anionic fraction, malic acid recorded a maximum of 78.0 μg plant–1 followed by oxalic, succinic, citric and glutamic acid fractions. The neutral fractions included different saccharides, among which, fructose recorded a maximum of 42.5 μg plant–1, followed by glucose, maltose, ribose and arabinose. The relative chemotactic response (RCR) of PGPB (plant growth-promoting bacteria) strains towards different root exudate fractions of Acorus calamus was recorded and it was observed that the combination of Anionic + Cationic + Neutral fraction recorded maximum chemotactic response for PGPR strains. The adsorption of PGPR strains in the root of the Acorus calamus was recorded in three different phases of growth and among these, Log phase bacterial cells exhibited maximum colonization of 7.65 × 10–6 cells g–1 with A.venilandii (ACAzt-2). Inoculation effect of PGPB strains on the root exudate of Acorus calamus and its growth was evaluated and it was observed that the treatment T5 – Consortium recorded maximum plant height and root growth of Acorus calamus, followed by T2. Our results indicate that sweet flag root exudates induce chemotactic responses of PGPR strains and promoted their growth.
  • Kirje
    Effect of different substrate sterilization methods on performance of oyster mushroom (Pleurotus ostreatus)
    (Estonian Academic Agricultural Society, 2021) Shrestha, Sanju; Bhattarai, Samikshya; Shrestha, Ram Kumar; Shrestha, Jiban
    Proper sterilization of substrates is an indispensable step in oyster mushroom cultivation. Oyster mushroom growers in Nepal usually follow three different substrate sterilization methods; however, their comparative effectiveness is vastly unexplored. Thus, these experiments were carried out at the Institute of Agriculture and Animal Science (IAAS), Lamjung Campus, Lamjung, Nepal from January to March, in the years 2017 and 2019. The objective of these experiments was to identify the most appropriate method of sterilization. Three different types of sterilization methods viz chemical sterilization (formaldehyde + carbendazim), steam sterilization, and hot-water sterilization were evaluated for the growth parameters and productivity of oyster mushroom cultivated on rice straw. The experiments were laid out on Completely Randomized Design (CRD) with ten replications. The results showed that the spawning rate was 3.2% of the wet substrate. Data were collected until the third flush. A significantly longer duration to colonize the substrate (29.7 days) was observed under chemical sterilization. The oyster mushroom performed best under steam sterilization as it took the shortest time for pinhead formation (34.30 days), fruiting body formation (43.60 days), cropping duration (89.30 days), and produced the highest mushroom yield (1401.9 g per 4 kg bag), and consequently, the highest biological efficiency (101.38%). Average pileus diameter and stipe length were statistically indifferent among the treatments suggesting the significant effect of sterilization methods on the yield of oyster mushroom but not on its morphological attributes.
  • Kirje
    Kasvuregulaatori ja kevadise täiendava lämmastikväetise mõju põldtimuti (Phleum pratense L.) seemnesaagile ja seemnete kvaliteedile
    (Estonian Academic Agricultural Society, 2021) Bender, Ants
    The synergistic effect of the plant growth regulator Moddus 250 EC and nitrogen fertilizer on the seed yield and seed quality of timothy was investigated over a period of four years (2017–2020) in a field trial established with the cultivar 'Tika' in 2016 at the Estonian Crop Research Institute. The trial had three variants: variant 1 – without plant growth regulator (control), variant 2 – plant growth regulator sprayed twice at the rate of 0.4 + 0.4 l ha–1 and variant 3 – plant growth regulator sprayed once at the rate of 0.8 l ha–1 . In all three variants there were five nitrogen fertilizer rates between N 70–140 kg ha–1 . In the trial the lodging resistance of plant cover was monitored, the height of generative tillers was measured, the seed yield was determined by two-phase combine harvesting and the quality of seed was determined. No lodging of timothy was detected in trial variants throughout all trial years. The increase of nitrogen fertilizer rate did not reliably affect the height of generative tillers, the split application of plant growth regulator shortened the height of generative tillers on the average of four years by 7.4%, and one-time spraying by 6.2%. The use of plant growth regulator did not increase the seed yield, the split application of it even reduced the seed yield. The increase of nitrogen fertilizer rate up to N 122 kg ha–1 increased the seed yield reliably only in the first year of production, but not in the following years. The use of plant growth regulator slowed down seed maturation, in our trials it was confirmed by bigger amounts of seed in the second harvest phase. The increase of nitrogen fertilizer rate and the use of plant growth regulator did not have any effect on seed germination. In the first production year, the 1000 kernel weight increased under the influence of plant growth regulator, in the later years there was no effect. The germination energy of seed somewhat decreased under the influence of plant growth regulator.
  • Kirje
    Identification of mathematical description of the dynamics of extraction of oil materials in the electric field of high frequency
    (Estonian Academic Agricultural Society, 2021) Bandura, Valentyna; Kotov, Boris; Gyrych, Sergey; Gricshenko, Volodymyr; Kalinichenko, Roman; Lysenko, Oksana
    One of the most important stages of the technological process of extraction of target components from oilseeds is extraction. This stage lasts the longest, and therefore, it generally determines the speed and cost-effectiveness of the whole process. A promising direction for effective organization of the extraction process is involving microwave technologies, the use of ultra-high frequency electromagnetic field (EHF) microwave energy directly in the technological process. The complex nature of the interaction of the factors that determine the intensity of the extraction process in the microwave field does not allow establishing (create) an exact mathematical model of extraction. We propose a method of parametric identification of the mathematical description of the extraction dynamics. This method allows determining the kinetic coefficients of the process from one experimental experiment on the existing installation. A simplified process mechanism was chosen for the study and a general description of the phenomena of heat and mass transfer in a capillary-porous body was used for the known general description. The parameters of the obtained model were identified according to experimental studies. The thus obtained model of non-stationary processes can be used to optimize the parameters and automate the technical means of extraction of oil materials.