2017, Vol. 15, No. 5
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Sirvi
Sirvi 2017, Vol. 15, No. 5 Märksõna "articles" järgi
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Kirje The advantage of Decision Support System for managing spring barley disease in Estonia(2017) Sooväli, Pille; Koppel, Mati; Lauringson, Enn; Talgre, LiinaA Decision Support System (DSS) I - Taimekaitse focusing on use of timely applied and reduced fungicide rates in control of cereal diseases has been tested in field trials since 2003 . We compared the conventional treatment and the DSS - based spray practices in 18 field trials in five agricultural locations over 7 - year period. Efficacy of the control of net blotch caused by Pyrenophora teres (Drechsler, am Drechlera teres Sacc. Shoem), the main fungal disease in spring barley has been tested to determine the economic advantage of DSS use. Compared with the conventional spray practices, the advantage I - Taimekaitse resulted in reduction of application doses by 30 to 60% of the registered rate. According to I - Taimekaitse , the fungicides were applied mainly between heading and flowering growth stages (GS 55 – 65), whereas traditional routine spraying is commonly made at booting (GS 37 – 49) . The experiment clarifies the cost - benefit of using DSS - based approach in barley disease management with average yield increase above the control in 12.8% and above the conventional treatment in 14.1%. I - Taimekaitse gave competitive disease control and average yield output reduction compared with conventional practice by 9%. In general the Treatment Frequency Index applied in conventional treatment was 0.65 and in DSS 0.41. Although the cost of treatment expense in DSS was 20% less compared with conv entional practice, the performance of conventional used spray practices was outstanding in economic return.Kirje AFLP-analysis of genetic diversity in soybean [Glycine max (l.) Merr.] cultivars Russian and foreign selection(2017) Zargar, M.; Romanova, E.; Trifonova, A.; Shmelkova, E.; Kezimana, P.Genetic diversity of 11 cultivars of soybean (Glycine max) from a VIR (N.I. Vavilov Institute of Plant Genetic Resources) collection was analyzed by the AFLP (amplified fragment length polymorphism) technique. From 18 tested primer combinations, both of them were selected for further analysis. From these two primer combinations (E32/M60 and E32/M59), 90 DNA fragments were obtained, 39 (43%) of them were polymorphic. Unique DNA fragments were found in accessions SibNIISHoz 6, Soer-4, Determinant. The Jaccard's similarity indices varied from 0.79 (between Sonata and Ugra) to 0.94 (between Ugra and Garmoniya) with an average of 0.775. Cluster analysis placed the cultivars into the several groups but separation in groups was not related to their origin or biological characteristics, even though cultivars Nordik and Soer-4 (cultivars recommended for Central Black Earth region of Russia) clustered together on the dendrogram. The obtained high values of Jaccard genetic similarity index and low level of polymorphism and differentiation illustrated a relatively low genetic diversity in our studied cultivars, which correlated with different other studies on soybean genetic diversity with AFLP-analysis.Kirje Anaerobic co-digestion of oil refinery wastewater and chicken manure to produce biogas, and kinetic parameters determination in batch reactors(2017) Mehryar, E.; Ding, W.M.; Hemmat, A.; Hassan, M.; Bi, J.H.; Huang, H.Y.; Kafashan, J.In order to improve the anaerobic fermentation of oil refinery wastewater (ORWW) via an appropriate nutrients pool for microbial and buffer capacity growth, a study was carried out on related anaerobic co-digestion (AcoD) with a rich organic carbon source, namely chicken manure (CM). The kinetic parameters were investigated (including cumulative biogas production, bio-methane content, retention time, and soluble chemical oxygen demand stabilisation rate) of batch AcoD experiments related to six ORWW:CM-ratio treatments (5:0, 4:1, 3:2, 2:3, 1:4, and 0:5) under mesophilic conditions. The highest soluble chemical oxygen demand removal rate was obtained for the 4:1-ratio treatment. However, the highest biogas production and bio-methane contents were achieved for the 1:4-ratio treatment. When taking into consideration the highest oil refinery wastewater portion in the AcoD mixtures and the statistical test results (LSD0.05) for the kinetic parameters, it can be seen that the 4:1-ratio treatment provided the maximum biogas production levels.Kirje Analysis of Arabidopsis defensin-like genes and ovule development during fertilization and Fusarium infection(2017) Spalvins, K.; Blumberga, D.Defensins are small, highly stable antimicrobial peptides. Many defensin-like (DEFL) peptides found in flowering plant Arabidopsis thaliana are believed to have role in either natural immunity or cell-to-cell communication during fertilization. However, little is known about the DEFL peptides and their functions during these events. The goal of this work is to investigate the genes encoding selected DEFLs by observing their expression patterns during fertilization and Fusarium graminearum infection. According to the results 4 selected genes of interest (GOI) are downregulated after fertilization and infection and mock treatments are causing degradation and delay of development in treated ovules.Kirje Assessment of different growing conditions for enhanced postharvest quality and shelf-life of leaf lettuce (Lactuca sativaL.)(2017) Lee, J.-S.; Nath, U.K.; Goswami, G.; Nou, I.S.Lettuce is the most important leafy vegetable. It is exclusively used as freshly raw form but sometime also as cooked. However, its quality depends on several pre- and postharvest factors. The effects of growing conditions and cultivars on the postharvest quality of leaf lettuce were investigated. In this experiment the interaction of variable factor; like growing conditions and fixed factor; cultivars are also observed. The leaf lettuce cultivars ‘Cheongchima’, ‘Cheongchuckmyeon’, ‘Geockchima’ and ‘Geockchuckmyeon’ were grown under favourable (natural condition) and unfavorable growing condition (with excess soil water and 50% shading) to evaluate their shelf-life and postharvest qualities. Plant height and the number of leaves were significantly varied in different growing conditions and by cultivars. In addition, fresh weight was affected by only growing condition, whereas leaf thickness was influenced by cultivars, growing conditions and the cultivars influenced the degree of fresh weight loss and respiration rate during postharvest storage. However, the postharvest storage qualities differed with cultivars and in combination with growing conditions.Leaf thickness and quality of leaf lettuce before and after harvest were also varied by cultivars and growing conditions. It could be concluded that postharvest leaf lettuce quality remains acceptable when growing under excess soil water with 50% shading.Kirje Band structures for binding and holding of objects made from recycled metallic materials(2017) Mironovs, V.; Boiko, I.; Lisicins, M.; Zemcenkovs, V.The aim of the present research is the investigation of the possibility and effectiveness of using the band structures made from recycled metallic materials for binding and holding of objects (in particular, tubular objects as pipelines or shells). The using of band elements and structures as such is a perspective way to increase the safety and bearing capacity of the pipelines and vessels. Nowadays during repair works the outer surfaces of the mentioned objects are braided by the steel tapes, i.e. the objects are strengthened by the binding. The mentioned steel bands are specially produced for binding purpose. From the other hand after stamping of smallsize details (like the elements of supply chains for different apparatus) the metallic waste in the shape of perforated metallic tapes are received and needs to be reused in compliance with the good practice in effective resource using and recycling. The band structures for binding and holding of tubular objects, produced from the perforated metallic tape by the longitudinal profiling, multilayer and spiral winding are presented. It is proposed to apply in industry the composite band structures made from perforated metallic materials and epoxy matrix for binding and holding of tubular objects as pipelines or shells, which allows simplifying and speeding up the repair works especially in the cases of the local damages.Kirje Carbon content of below–ground biomass of young Scots pines in Latvia(2017) Jansons, Ā.; Bārdulis, A.; Ķēniņa, L.; Lazdiņa, D.; Džeriņš, E.; Kāpostiņš, R.Forest ecosystems play crucial role in global carbon cycling, therefore, increasing afforestation of agricultural land in Europe has been recognized as important contribution of carbon sequestration. In carbon reporting systems, root carbon content (CC) default value has been set to 50%. The study aimed to estimate CC in below–ground biomass and in relation to tree age in young Scots pine stands on forest and former agricultural land. The below–ground CC of young (8 to 40 years) managed Scots pine (Pinus sylvestris L.) stands growing on nutrient poor mineral soils in Latvia was carried out. In total 62 sample trees (43 in forest land, 19 in former agricultural land) were randomly selected for destructive sampling to estimate the CC within below–ground biomass. Below–ground biomass weighted mean CC was 49.7 ± 0.4%, being slightly lower than the default CC value used to calculate carbon budgets. Root fractions stump, small roots (diameter 2–20 mm), coarse roots (diameter > 20 mm)) differed (p < 0.001) in their CC. Stumps (50.6 ± 0.6%) had highest (p < 0.001) CC in the below–ground biomass, followed by coarse (49.5 ± 0.4%) and small (49.1 ± 0.4%) roots, which did not differ from each other in their CC. Results demonstrated age–dependent increase of CC (p < 0.001) from 48.2 ± 0.3% to 51.7 ± 0.5%, indicating overestimation of the default value during the first two decades, but underestimation for older trees (24 to 40 years).Kirje Chemical composition of seeds and green beans of common bean varieties, breeded in Omsk State Agrarian University under conditions of southern forest-steppe zone of Western Siberia(2017) Kazydub, N.; Pinkal, A.; Marakayeva, Т.; Kuzmina, S.; Korobeinikova, M.; Kotsyubinskaya, O.The article considers the biochemical composition of green beans and seeds of common beans varieties, breeded in Omsk State Agrarian University named after P.A. Stolypin (OmSAU). The research was conducted in 2014–2016. Varieties of locally breeded beans, in comparison with the standards, have advantages in the content of protein, zinc, iodine, calcium, iron, sugar; green bean technological properties and tenderizing of seeds during cooking, which becomes an indispensable component of the diet.Kirje The content of weed seeds in the soil based on the management system(2017) Kuht, Jaan; Eremeev, Viacheslav; Talgre, Liina; Madsen, Helena; Toom, Merili; Mäeorg, Erkki; Loit, Evelin; Luik, Anne; Estonian University of Life SciencesIn 2008 an experiment was set up on the field in Eerika experimental station (Estonian University of Life Sciences) as a 5-field crop rotation: barley (Hordeum vulgare L.) with undersown red clover, red clover (Trifolium pratense L.), winter wheat (Triticum aestivum L.), pea (Pisum sativum L.), potato (Solanum tuberosum L.). The objective of the study was to measure the content of weed seeds in the soil and to evaluate the diversity of the species at the beginning of the period of organic production in 2011. In conventional farming systems without fertilizer (Con I) and conventional farming with mineral fertilizer (Con II) herbicides were used for weed control. All the crops in Con II system received P 25 kg ha-1 and K 95 kg ha-1 , but the application rates of mineral nitrogen fertilizer differed. In organic systems (Org I – organic farming based on winter cover crop and Org II – organic farming based on winter cover crop and manure), the winter cover crops (ryegrass after winter wheat, winter oilseed rape after pea, winter rye after potato) were sown after the harvest and were ploughed into the soil as green manure in spring. Organic farming systems (Org II) had a negative effect on the content of weed seeds in the soil (2.0–22.7% less seeds than in other variants). The seeds of Chenopodium album were the most abundant among summer annual weeds and the seeds of Viola arvensis among winter weeds in the soil. Organic farming measures increased the domination of Chenopodium album – the dominance index D’ was increased by 0.09–0.14 compared to conventional variants. The content of seeds of winter weed Viola arvensis in Org II variant was decreased by 82%. The index of species evenness J’ and Shannon Wiener diversity index H’ were lower in organic plots by 0.10– 0.18 and 0.60–0.19, respectively. Org II variants showed the best results based on the decrease of soil weed seed bank and distribution of the weed species.Kirje Determination of mechanical properties of poppy waste pellets(2017) Kažimírová, V.; Kubík, Ľ; Chrastina, J.; Giertl, T.The work deals with evaluation of mechanical properties three types of pellet samples produced fro m poppy waste. The pellets were submitted to compressive loading. The compressive loading curves of dependencies of force on strain and force on time were realised. Certain mechanical parameters were determined, namely the diameter of the sample, length of the sample, force at 10% of strain, force in the first maximum of the force – strain curve, strain in the first maximum of the force – strain curve, modulus of elasticity, force in the inflex point of the force – time and force – strain curves and strain and stress in the inflex point of the force – time and force – strain curves. The work lists correlations of mechanical parameters of individual pellet types. The pellet type 1 made only of ground poppy head mass has shown the best results, the pellet type 3 consisting of ground poppy heads after harvest and waste from sieving of poppy seeds in mass proportion 1 : 1 has shown the worst results.Kirje Dimethyl ether as a renewable fuel for diesel engines(2017) Zeman, P.; Hönig, V.; Procházka, P.; Mařík, J.The area of automotive fuel, or fuel components, which can be produced from biomass also includes dimethyl ether, otherwise known as DME. The issue of the use of DME as a fuel is one which has been monitored until recently. Biomass can also be used as the raw material for the production of DME. DME has therefore replaced the previously-used CFCs (chlorofluorocarbons), which are now banned for their role in dangerous levels of ozone depletion. With regard to its physical properties and combustion characteristics, it is currently expected that DME will soon apply significantly as a fuel in the municipal sector and in households, and as an alternative fuel for motor vehicles with diesel engines. DME is a suitable fuel for diesel engines and can be considered as one of the most promising diesel fuel replacements. DME is a suitable fuel for diesel engines mainly due to its low self-ignition temperature and good cetane figures. It is well miscible with most organic solvents and because the polar solvent is water-immiscible. The advantage is its high levels of purity, and its being free of sulphur, nitrogen, or metals. The physical properties of DME are very similar to the physical properties of LPG. DME requires relatively complex and costly fuel accessories, but the original compression ratio of the diesel engine is maintained. A diagram of the fuel system is illustrated in the paper. The paper analyses the dependence of vapour pressure on temperature, the dependence of the density on temperature, kinematic viscosity, the flash point, the boiling point, and the solubility of water. The objective is to evaluate this interesting energy source for applications in diesel engines.Kirje The effect of bedding amount on gas emissions from manure during storage(2017) Šimon, J.; Vegricht, J.; Bradna, J.One of the major agricultural pollutants of environment is manure from livestock. We focused on dairy cows kept in the barns with straw bedding commonly used in the Czech Republic. We tested the hypothesis that the amount of bedding used daily relative to the number and size of animals kept has a significant effect on the emissions of gases from manure stored in a manure pile. In the experiment, a group of 10 dairy cows of Holstein and Czech Red Pied breed was housed in a stable bedded with various amounts of wheat straw (4–10 kg/livestock unit per day). The manure was removed from the stable after 48 h and mixed was stored in cubic containers with drain floor allowing measurement of manure leachate release. For 50 days we measured weight, volume, weight of manure leachate and manure temperature. Decreasing stored manure weight can be attributed to release of manure leachate and emissions of gases, primarily water vapor, as a result of microbial activity and increased temperature in the manure during storage. Using the calculated model, we found that daily production of emissions of water vapor and other gases was related to bedding amount in a statistically significant manner (P < 0.001). The cumulative amount of gas emissions grew rapidly in all treatments. Also total amount of emissions was related to bedding amount in a statistically significant manner (P = 0.004). We also found the relationship between internal manure temperature and the logarithm of the amount of emissions produced to be statistically significant (P < 0.001).Kirje Effect of flame weed control on various weed species at various developmental stages(2017) Mojžiš, M.; Vitázek, I.; Klúčik, J.Physical methods of weed control as solarization, mulching, use of electricity, steam and flame are now an alternative in the organically grown crop. Flame weeder already has a wide range of practical use , particularly in the cultivation of vegetables in alternative form without any chemical treatment. Compared to chemical spraying, the use of flame weeder is more expensive, but we can compensate the costs by the added value of bioproducts. The issue of costs affects the wider use of the method in practice, but it may be offset by increased e fficiency of weed control. The correct parameters of flame weeder, such as burner angle, burner height, the gas pressure, speed of weeder as well as the growth stage of the weed, weed species, climate conditions etc., can increase the effectiveness of weed control. Field and laboratory tests carried out in Canada and Slovakia were aimed at verifying the influence of parameters on the effectiveness of flame weed control.Kirje Effect of slurry lagoon redesign on reduction of ammonia emission during livestock manure storage(2017) Aboltins, A.; Priekulis, J.; Aboltina, B.; Melece, L.In accordance with the international and EU aims to reduce emissions of ammonia and other air pollution substances farm manure management, including its storage, especially for the animal breeding sector, is one of the most essential stages. One of the preventing steps is covering of the slurry lagoons. The most effective – hard covering can be provided only after the lagoon is constructed. The aim of the research: to develop methodology for calculations of emission reducing lagoon design volume and surface area. In the result of the theoretical research the possibilities of reducing the reflection surfaces at the same capacity of the lagoon have been discovered, as well as the changes of the reflection surface area, if instead of one lagoon several lagoons with less volume are installed and sequential filling of these lagoons is ensured. The article presents the calculation algorithms obtained during the research and recommendations for construction of low emission lagoons.Kirje Effects of irrigation applied at different growth stages on chickpea yield(2017) Kirnak, H.; Varol, I. S.; Irik, H. A.; Ozaktan, H.This study was conducted over the experimental fields of Erciyes University in 2016 to investigate the effects of irrigations applied at different growth stages on chickpea yields. Experiments were conducted in randomized blocks design with 3 replications. There were 7 irrigation treatments as of I1: rainfed, I2: pre-bloom single irrigation, I3: single irrigation at the beginning of blooming, I4: single irrigation at 50% pod set, I5: two irrigations at 50% bloom and 50% pod-set, I6: two irrigations at pre-bloom and 50% pod-set, I7: full irrigation. The amount of applied irrigation water varied between 85.6–323 mm. Plant water consumptions varied between 262 – 569 mm. The greatest yield was obtained from I4 treatment with 273 kg da-1 and the lowest yield was obtained from I1 treatments with 146 kg da-1. It was concluded for chickpea cultivation under deficit water resources conditions that water deficits may be applied at different growth stages except for 50% pod-set period.Kirje Effects of Irrigation water salinity on evapotranspiration and spinach (Spinacia oleracea L. Matador) plant parameters in Greenhouse Indoor and Outdoor Conditions(2017) Ünlükara, A.; Yurtyeri, T.; Cemek, B.Response of spinach to irrigation water salinity under greenhouse indoor and outdoor conditions was investigated in this study to reveal different weather conditions on salinity tolerance of the plant. For this purpose, saline waters at six different salinities (0.65, 2.0, 3.0, 4.0, 5.0 and 7.0 dS m-1 ) were applied to spinach (Spinacia oleracea L. Matador) grown in pots. Soil salinity increased linearly with increasing salinity of irrigation water. Threshold salinity is 2.35 dS m-1 and yield lost slope after this threshold is 3.51% for indoor and threshold salinity is 2.83 dS m-1 and yield lost slope is 3.3% for outdoor. Salinity harmful effect on spinach yield is higher for indoor conditions than for outdoor conditions because of higher indoor temperatures. These results apparently showed that spinach salinity response could change with changing weather conditions especially for temperature. Yield response factors (ky), which is the ratio of relative evapotranspiration decrease to relative yield decrease, were close in the cases of irrigation water salinity in greenhouse outdoor and indoor (ky = 2.4 and 2.1), respectively. Considerable water consumption decreases because of salinity were determined. Every 1 dS m-1 increment in soil salinity caused about 1.35% water consumption decrease for spinach. Therefore, depressing effect of salinity on water consumption should be considered in irrigation and salinity management to prevent excess saline water application and to protect environment.Kirje Evaluation of smart economy development in the RIGA planning region (LATVIA)(2017) Rivža, B.; Āzena, L.; Rivža, P.To evaluate the potential development of smart economy in the Riga planning region (henceforth – RPR), it is important to understand the present situation in the region, its specificity, and role in the context of provisional future trends. Two approaches have been employed in the present study to evaluate the situation on a regional level. One includes the collection and comparison of the basic economic development indicators, whereas AHP method has been used in the second approach, where 5 experts expressed their opinion on the options of potential development of smart specialisation in the RPR. RPR as a capital city region is pronouncedly monocentric, with Riga city as its socioeconomic core that develops a wide network of functional ties, and creates a home for the part of the society that works in Riga, but lives in the adjacent suburban territories – Pieriga. Traditionally the basic indicators of development include only the demographic and economic indicators. Sometimes these results are not objective, do not describe the potential for development, but clearly show the inequal social and economic situation in the region. To characterise the economic development in the RPR, we will include the economic profile data, statistical data and expert opinions on the population, regional government, state and EU influence on the development of the Pieriga region smart specialisation.Kirje Influence of chemical composition on the biochemical methane potential of agro-industrial substrates from Estonia(2017) Luna-del Risco, M.A.; Orupõld, Kaja; Diaz-Forero, I.; González-Palacio, M.; Estonian University of Life Sciences. Faculty of Agricultural and Environmental SciencesBatch trials were carried out to evaluate the Biochemical Methane Potential (BMP) of 61 different substrates collected from agricultural farms and industrial sites in Estonia. Tests were performed in 500 mL plasma bottles at 36°C. The highest methane yield from all tested substrates was obtained from unconsumed dairy products (557 ± 101 L kg-1 VS) while the lowest was obtained from animal slurries (238 L kg-1 VS ± 42). From tested energy crops, foxtail millet achieved the highest methane yield (320 L kg-1 VS). Silages from different crops presented methane yields from 296 ± 31 L CH4 kg-1 VS to 319 ± 19 L CH4 kg-1 VS. The influence of chemical composition and kinetic rate constants (k) on methane potential was analyzed. Anaerobic digestibility of selected agro-industrial substrates was markedly influenced by their organic content, i.e. total proteins and lignin concentrations. Rate constants were found to correlate negatively with hemicellulose, cellulose and lignin (p < 0.05). Results from this study suggest that an appropriate characterization of the chemical composition of the substrates is important not only for predicting BMP and the kinetics rates, but also for identifying possible inhibitors during the anaerobic digestion process. Results on the BMP and national availability of studied substrates indicate that herbal biomass and agro-industrial residues are promising substrates for biogas production in agricultural biogas facilities in Estonia.Kirje Influence of tied ridging technology on the rate of surface runoff and erosion in potato cultivation(2017) Vejchar, D.; Stehlik, M.; Mayer, V.Water management and securing good condition of soil is becoming an important factor in agriculture one of the reasons being adaptation to the increasingly frequent extremes in weather. Tied ridging technology enables to reduce significantly the loss of water and soil from arable land. The effect of a tied ridger mounted on 2-row planter and effect of 6-row tied ridger on basin renewal was tested in potato cultivation on plots of land with length of 10 m. During entire season lasting 135 days the technology helped achieve 78% of efficiency in reduction of surface water runoff and 88% of efficiency in case of soil loss. In the case of furrows with only tied ridging the water retained represented additional 15% of total water from rainfall (37.5 mm of 250 mm) over untreated furrows. In the case of basins formed in furrows with wheel trails the water retained represented 15% of total water from rainfalls in the trail. This water retained on the land would have otherwise flown off and would not have been utilized without this technology. The renewal of dams after 1/3 of the season increased significantly the efficiency of this technology. The technology of tied ridging significantly contributes to sustainable agriculture management.Kirje Instrumental and sensory evaluation of seven apple (Malus domestica Borkh.) cultivars under organic cultivation in Sicily(2017) Farina, V.; Gianguzzi, G.; Mazzaglia, A.; Sortino, G.In this trial we examined the quality of 7 clones belonging to more diffused apple polyclonal varietal groups, using chemical/physical and sensory analyses during two consecutive years. Galaxy, and their ameliorative clones Gala Annaglò® and Dalitoga (Gala clones) that ripen in summer, Erovan* Early Red One® and Scarlet Spur*-Evasni® (Red Delicious clone), Corail Pinova and its ameliorative clone RoHo 3615 * Evelina® that ripen in autumn were studied. Gala Annaglò® is interesting for the fruit size and peel color, Dalitoga for the early ripening and Galaxy for the crunchiness and consistency. All the Gala clones reached very high total solid soluble content confirmed by the panel judgment of the sweetness and acidity descriptors. The Red Delicious clones confirm the larger size and the high colorimetric standard of all covered red fruits; the new clone Scarlet Spur*-Evasni® reached an interesting fruit size and peel colour intensity and uniformity, and the best total solid soluble content to total acidity ratio confirmed by the sensory descriptors of acidity and sweetness. Moreover, it reached very high values of crunchiness, consistency and interesting values of apple flavour, honey flavour and fruit flavour. The ameliorative clone RoHo 3615*Evelina® was characterized by well uniform and intense coloured fruits and a more balanced total solid soluble content to total acidity ratio, and interesting values of crunchiness, consistency, apple flavour, honey flavour and fruit flavour. This study confirms the relationship between instrumental and sensory analysis.