2019

Selle valdkonna püsiv URIhttp://hdl.handle.net/10492/5382

Sirvi

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Typology of small producers in transition to agroecological production
(2019) Escobar, N.; Romero, N.J.; Jaramillo, C.I.
Agroecology is now emerging as the fundamental science to guide the conversion of conventional production systems to more diversified and self-sufficient systems. The agroecological transition is defined as the gradual change that farmers undergo to adapt and move from more conventional towards agroecological farming principles, encompassing technological, societal, institutional and organisational changes in the food system. To analyze a transition process, it is initially necessary to understand how agroecosystems work (their structure and processes), and the different ways human beings intervene an ecosystem in order to transform it for productive purposes.Farm systems typology and classification techniques are used to guide strategic lines of research, sectorial policies, and promote sustainable development in response to farmer’s needs. Determining multidimensional classification methods in agricultural systems is necessary, considering both the variables inherent to the production system and those of an external nature that indirectly impact the development and long-term sustainability of production systems. One of the purposes of this research was to characterize agricultural production based on sustainability systems and environmental, social, and economic indicators. The study was carried out based on data collected from 71 farm surveys, considering the social, economic, environmental, and technological dimensions. Multiple correspondence and cluster analysis were done. Three types of production systems were obtained: Group I, organic producers in transition; Group II, conventional producers in transition to organic production; and Group III, conventional producers interested in organic production. Producers need to focus on processes that allow them to improve their skills to develop human talent and social capital in terms of integration, collaborative work, trust, political and cultural capital, so that they can make progress easily and start implementing agroecological, infrastructure, and natural resources management practices, while improving their living standards. The information yielded by a typology process allows for us to know the current state of agricultural production systems based on the implementation of agroecological practices; thus facilitating the preparation and implementation of participatory plans and/or integrative proposals that promote agrofood sustainability.
Effective control and battery charging system of an island PV power plant
(2019) Papez, V.; Papezova, S.
The paper presents a new concept of an autonomous PV power plant regulatory system with LiFePO4 batteries, which was functionally verified. The hardware system is significantly simpler and more operationally reliable. It also shows higher efficiency and lower acquisition costs than conventional commercial systems. The proposed control system was optimized for charging a multi-cell battery by PV electric energy. The system automatically maximizes the power supplied by the photovoltaic source and minimizes the power loss caused by balancing the individual cell charging processes. The problem of charge balancing is solved without the balancers. Battery cells are recharged from the separate converters supplying the PV power. The converters are controlled to observe a LiFePO4 battery charging mode while controlling the photovoltaic generator (PVG) load resistance based on an MPP monitoring. PVG power is not supplied to the charged cells, which are in this way protected from overcharging. The entire PVG power is fed to the cells to be charged. The transmission from the converters is controlled in order not to exceed the voltage and current limits at the terminals and to minimize the actual voltage deviation from the control voltage at the PVG output. The control voltage is generated as an MPP voltage approximation according to the load character-istics and the actual PVG operating conditions.
Possibilities of monitoring cattle via GSM and A-GPS
(2019) Sirotek, A.; Hart, J.
Nowadays, people and things can be localized using GNSS (Global Navigation Satellite System) or GSM technology. Devices using Differential Global Positioning Systems may not be suitable for they computing and energy intensity. The GSM and A-GPS systems have certain limitations and disadvantages. They are different in accuracy, energy intensity and therefore they are suitable for different applications. Trackers can’t be effectively used to locate animals, monitor their movements, and observe their behaviour. They can also be used to search for stolen pets and farm animals. Unguarded herds of cattle are often the target of thieves. For reasons of crime, localization was tested by devices using GSM and A-GPS technology. Specifically, the quality of these localization methods has been tested. Has been addressed above all, accuracy, reliability, speed and consistency of individual methods. In addition, further measurements were made. Localization has been tested in different well-defined environments. This makes it possible to judge the quality of individual localization technology and to suggest the best use of individual technologies and their link.
Pericarp of colored-seeded common bean (Phaseolus vulgaris L.) varieties a potential source of polyphenolic compounds
(2019) Nurzyńska-Wierdak, R.; Łabuda, H.; Buczkowska, H.; Sałata, A.
Bioactive substances produced by plants are defined as secondary metabolites causing different pharmacological effects in human organism. Various plant raw materials, some known as vegetables or spices, are their source. Pericarp of white-seeded common bean varieties is a pharmacopoeial product traditionally used as an antidiabetic agent. The object of this study was to evaluate the biological value of pericarp of colored beans (cultivars: ‘Małopolanka’, ‘Nida’, ‘Rawela’, ‘Tip Top’, and ‘Nigeria’) compared to the reference white-seeded cultivar (‘Laponia’). Bean pericarp was characterized by a high level of polyphenolic compounds and antioxidant activity. Its phenolic acid content (expressed as caffeic acid equivalents) was at a similar level, at least 0.1 mg g -1 (0.01%). The highest amount of flavonoids was accumulated by the cultivars with dark blue and black seeds, respectively 0.138 and 0.139 mg g -1 DW, as well as by the whiteseeded cultivar (0.132 mg g -1 DW). The highest antioxidant activity (AA) was found for bean extracts of the cultivars ‘Laponia’ and ‘Małopolanka’, respectively 12.35 and 12.10%. Phenolic acid content was significantly positively correlated with AA of the bean extracts tested. This study indicates that pericarp of the colored-seeded bean cultivars is characterized by high biological value and can be used as a source of polyphenolic compounds.
Selenium in nanosized form as an alternative to microfertilizers
(2019) Chernikova, O.; Mazhayskiy, Yu.; Ampleeva, L.
Nowadays, it is an obvious fact that it is necessary to look for new approaches to agriculture, which would ensure the maximum reduction in the dependence of the volumes and quality of the crop on external factors. The use of nanopreparations in crop production is the most promising. The development of new technologies and techniques using nanomaterials, which would ensure high yields and quality of potato products, is relevant and has great practical importance. The research in recent years has established the important role of selenium in the regulation of plant activity.The purpose of this work was to research the effect of selenium nanoparticles and selenium in the form of micronutrient fertilizers on early-maturing varieties of potatoes for table use: adaptive capacity and nutritional value. Selenium nanopowder in the form of a solution contained the optimum nanoselenium concentration applied–0.13 g per hectare seeding rate. The potato tubers were soaked in distilled water 30 minutes before seeding. The treatment of potato tubers with selenium micronutrient, the dose of which amounted to 400 g per 1 hectare, was also carried out before planting. The soil preparation and agrotechnology cultivation generally accepted in the Ryazan region.The research results showed that presowing treatment of potato tubers with selenium nanopreparation had the most favorable effect on the adaptive capacity of plants (heat resistance, water-holding properties), as well as on yield increase, than treatment of tubers with selenium in the form of microfertilizer. The use of Se nanoparticles leads to an increase in the protein and vitamin C content. The Udacha potato variety showed great responsiveness to the entering of various forms of selenium in comparison with others. The use of selenium in the form of microfertilizer leads to an increase in the accumulation of starch and dry matter. These figures were the highest in potato tubers of the Zhukovskiy Ranniy variety.
Properties of soil and peat humic substances from Latvia
(2019) Klavins, M.; Purmalis, O.; Grandovska, S.; Klavina, L.
The acidity, elemental, functional and spectral (UV, fluorescence, IR spectra) characteristics of humic substances isolated from soils of different origin and peat in Latvia are described and compared with values common for humic substances of different origin, to evaluate the character of processes during humification. Substantial dependence of properties of humic substances on the humification conditions are found.
The course of drying and colour changes of alfalfa under different drying conditions
(2019) Kic, P.
One of the conditions for successful livestock breeding and efficient livestock production is to ensure quality feed. High quality feed for livestock is alfalfa, which has a very high nutritional value and its cultivation is also important for crop production in terms of improving the soil structure and nitrogen enrichment. The aim of this paper is to inform about the experimental investigations of alfalfa drying and colour changes under different drying conditions. The results of natural convection at 27.5 °C and 40% relative air humidity are compared with forced convection at 1.2 m s -1 air flow velocity at the same air temperature and with results of drying by natural convection at 50 °C. The dry matter content was measured gravimetrically after drying in a hot air dryer at 105 °C. Higher drying rates shorten the time required for drying and earlier preservation and storage in the hayloft or in the hay bales. This reduces the risk of wetting of feed such by rain and degradation by fungi, etc. A shorter drying time is also important in terms of energy savings. The precise knowledge of the drying process and drying curves allows also to determine the appropriate time for storage and conservation for production of another type of fodder e.g. haylage or silage. The measurement results show a positive effect of higher drying speeds as well as increased air temperature. Higher drying air temperature during convection led to the partial lightening and greater yellowing of the feed.
The environmental noise level in the rejuvenation pruning on centuries-old olive tree
(2019) Abenavoli, L.M.; Zimbalatti, G.; De Rossi, A.; Papandrea, S.; Proto, A.R.
In the Italian agricultural economy, olive cultivation plays a fundamental role, and this is especially true for the southern regions where almost all cultivation is spread. In Calabria, in particular, olive cultivation has seen over the last few decades significantly improve the quality of production also as a result of investments aimed at the creation of new mechanizable plants and/or the modernization of existing ones; today some areas have got both PDO and PGI certification. In the ‘Piana di Gioia Tauro’, located north-west of the Reggio Calabria metropolitan area, olive growing extends over 20,000 hectares and the presence of centuries-old olive tree is still widespread. The olive varieties mainly belong to the local cultivars of ‘Sinopolese’ and ‘Ottobratica’, characterized by a remarkable rusticity and high development, perhaps unique in the world; they reach 20–25 meters high, forming what is called a ‘forest of olive trees’. The pruning operations are carried out by means of chainsaws of different power and size whereby, in addition to the previously described difficulties, operators are exposed to prolonged periods of noise levels. The purpose of this study is precisely to assess the exposure of operators to this particular olive grove. The aim is to identify the acoustic levels generated by the two pruning and cross-cutting activities, the risk thresholds and the exposure to which the individual workers of the two work sites are subjected, giving indications on the appropriate safety distances to maintain (according to current regulations) compared to noise sources.
Content of malondialdehyde and activity of enzyme glutathione-S-transferase in the leaves of emmer wheat under the action of herbicide and plant growth regulator
(2019) Karpenko, V.; Pavlyshyn, S.; Prytulіak, R.; Naherniuk, D.
The article presents the results of vegetation experiment on the influence of different rates of herbicide Prima Forte 195 – 2-ethylhexyl ether 2.4-D + aminopyralid + florasulam (0.5; 0.6 and 0.7 L ha-1 ) under different application methods of plant growth regulator of a natural origin Wuxal BIO Vita (Ascophyllum nodosum extract + microelements) on the content of malondialdehyde (MDA) as an important indicator of the intensity of peroxide oxidation of lipids in plants and on the activity of enzyme glutathione-S-transferase (GST) in the leaves of emmer wheat. Experimental scheme included 16 experimental variants: 1 – without application of preparations and pre-sowing treatment of seeds (control); 2, 3, 4 – Prima Forte 195, applied to vegetative plants at the rates 0.5, 0.6 and 0.7 L ha-1 ; 5 – Wuxal BIO Vita at the rate of 1.0 L ha-1 , applied to vegetative plants; 6, 7, 8 – Prima Forte 195 at the rates of 0.5, 0.6 and 0.7 L ha-1 in tank mixtures with Wuxal BIO Vita at the rate of 1.0 L ha-1 , sprayed on vegetative plants; 9 – pre-sowing treatment of seeds with Wuxal BIO Vita at the rate of 1.0 L t -1 (background); 10, 11, 12 – Prima forte 195, applied to vegetative plants at the rates of 0.5, 0.6 and 0.7 L ha-1 at the background of pre-sowing treatment of seeds with Wuxal BIO Vita at the rate of 1.0 L t -1 ; 13 – Wuxal BIO Vita at the rate of 1.0 L ha-1 (applied to vegetative plants, treated before sowing with Wuxal BIO Vita at the rate of 1.0 L t -1 ); 14, 15, 16 – Prima Forte 195 at the rates of 0.5, 0.6 and 0.7 L ha-1 respectively, in tank mixture with Wuxal BІО Vita at the rate of 1.0 L ha -1 – spraying of plants and pre-sowing treatment of seeds with Wuxal BІО Vita 1.0 L t -1 . It has been found that under the application of Prima Forte 195 the redox state in the leaves of emmer wheat increased considerably in the direction of increasing the content of MDA. It has also been proved that herbicide Prima Forte 195 and its mixtures with plant growth regulator (PGR) Wuxal BIO Vita caused the changes in the activity of enzyme glutathione-S-transferase, which slightly increased in the initial period in the variants of integrated application of herbicide and plant growth regulator. However, later the GST activity in the variants of integrated application of herbicide and PGR decreased, which indicates stabilization and a positive influence of integrated application of preparations on the detoxification processes in the crops of emmer wheat.
Spatial distribution of thermal variables, acoustics and lighting in compost dairy barn with climate control system
(2019) Damasceno, F.A.; Oliveira, C.E.A.; Ferraz, G.A.S.; Nascimento, J.A.C.; Barbari, M.; Ferraz, P.F.P.
The main objective of this research was to evaluate the spatial distribution of the thermal variables, acoustics and lighting in climate controlled compost dairy barn. The experiment was conducted in October 2017, in a farm located in the west of Minas Gerais state, Brazil. For the study, the interior of the animal facility was divided into 120 meshes equidistant points, in which air temperature (tdb), relative humidity (RH), noise, illuminance, and air speed (Vair) were manually collected. The technique of geostatistics was used to evaluate the distribution and spatial dependence of variables. Spatial distribution maps showed the occurrence of high variability of attributes and content within the animal facility. Thermal environment variables showed alert situations throughout practically the entire facility. The noise and luminance levels were within the recommended values.
Particle size and shape characterization of feedstock material for biofuel production
(2019) Chaloupková, V.; Ivanova, T.; Krepl, V.
Particle size and shape are key factors influencing the properties of particulate and agglomerated materials, and having an impact on a quality as well as utilization of a final product. In case of plant biomass particle morphology is greatly irregular. Large errors at most determinations of biomass particle sizes are caused by simplification on a single parameter of size, assuming particle sphericity or circularity. Thus, the aim of a present research was to determine the particle size in a complex way. Pine sawdust as an experimental material and typical biofuel feedstock was ground by a hammer mill to a fraction size of 12 mm. The dimensional features of such ground sawdust particles were identified for all particles individually via photo-optical analysis, a method based on a digital image processing that is sensitive to irregular particles’ shapes. The particles were described mainly by variables of length, max width, equivalent diameter, max and min feret diameter, sphericity, roundness, circularity together with length/width ratio and aspect ratio. Data were analysed by descriptive statistics, i.e. by arithmetic means, medians, minimum and maximum values, variance and standard deviation. The obtained results may contribute to a better knowledge of material properties needed for designing an optimal technology for the production of quality biofuels.
Geostatistics applied to evaluation of thermal conditions and noise in compost dairy barns with different ventilation systems
(2019) Oliveira, C.E.A.; Damasceno, F.A.; Ferraz, P.F.P.; Nascimento, J.A.C.; Ferraz, G.A.S.; Barbari, M.
The objective of this work was to evaluate the spatial distribution of thermal conditions and bed variables in compost dairy barns with different ventilation systems, through the technique of geostatistics. The experiment was conducted in April 2017, in farms located in Madre de Deus, Minas Gerais, Brazil. Three facilities were evaluated with different ventilation systems: natural (NV); mechanical of low volume and high speed (LVHS); and mechanical of high volume and low speed (HVLS). The interior of the premises was divided into 40 meshes equidistant points, in which air temperature, relative humidity and air speed were manually collected. Geostatistics technique was used to assess the spatial dependence of the variables. The results showed the occurrence of dependence and spatial variability of the variables evaluated. Based on thermal comfort indexes, it was concluded that dairy cows were under stress conditions during the hottest hours of the day in the three animal facilities evaluated. The results obtained allow us to understand that the thermal environment is more influenced by the ventilation system adopted.
Computational fluids dynamics (CFD) in the spatial distribution of air velocity in prototype designed for animal experimentation in controlled environments
(2019) Vilela, M.O.; Gates, R.S.; Martins, M.A.; Barbari, M.; Conti, L.; Rossi, G.; Zolnier, S.; Teles Junior, C.G.S.; Zanetoni, H.H.R.; Andrade, R.R.; Tinôco, I.F.F.
Maintaining a comfortable and productive thermal environment is one of the major challenges of poultry farming in tropical and hot climates. The thermal environment encompasses a number of factors that interact with each other and reflect the actual thermal sensation of the animals. These factors characterize the microclimate inside the facilities and influence the behaviour, performance and well-being of the birds. Thus, the objective of this study is to propose and validate a computational model of fluid dynamics to evaluate the spatial distribution of air velocity and the performance of a system designed to control air velocity variation for use in experiments with birds in controlled environment. The performance of the experimental ventilation prototype was evaluated based on air velocity distribution profiles in cages. Each prototype consisted of two fans coupled to a PVC pipe 25 cm in diameter, one at each end of the pipe, with airflow directed along the entire feeder installed in front of the cages. The contour conditions considered for the simulation of airflow inside the cage were air temperature of 35 °C at the entrance and exit of the cage; air velocity equal to 2.3 m s -1 at the entrance of the cage; pressure of 0 Pa. The model proposed in this study was representative when compared to the experimental measurements, and it can be used in the study of air flow behaviour and distribution for the improvement of the prototype design for later studies.
Effects of nitrogen, phosphorus and vermicompost fertilizers on productivity of groundnut (Arachis hypogaea L.) in Babile, Eastern Ethiopia
(2019) Bekele, G.; Dechassa, N.; Tana, T.; Sharma, J.J.
Though groundnut (Arachis hypogaea L.) is a main cash crop for smallholder farmers in several districts of eastern Ethiopia, its yield is very low. Farmers apply little or no fertilizers to grow the crop possibly because no generic or recommended fertilizers rates available for farmers. Therefore field experiments were conducted for two consecutive cropping seasons in Babile district, to prove the hypothesis that one of the major factors that severely reduce the yield of the crop was lack of nutrients in the soil with the objective of investigating the effects of applying mineral NP fertilizers and vermicompost on the productivity of improved groundnut variety ‘BaHa-Gudo’. The experiment was 3 × 3 × 3 factorial with three replications laid down in a randomized complete block design comprising nitrogen (0, 23 and 46 kg N ha-1 ), phosphorus (0, 46 and 92 kg P2O5 ha-1 ) and vermicompost (0, 2.5 and 5 t vermicompost ha-1 ). The data on crop growth, nodulation and yield were collected and subjected to analysis of SAS 9.2 software. Means separation were made using Duncans Multiple Range Test (DMRT) at 5% level of significance. The results revealed that growth, yield attributes, and yields were significantly (P < 0.01) affected by the main and interactions effect of the treatments. The pod yield obtained from combined application of 46: 46 kg N: P2O5 ha-1 and 2.5 t vermicompost ha-1 exceeded the pod yield produced from nil application of fertilizers by about 100%. The economic analysis also indicated that the highest marginal rate of return (671%) and net benefit ($ 1,830) ha-1 were obtained from combined application of 46: 46 kg N: P2O5 ha-1 and 2.5 t vermicompost ha-1 . From the results it could be concluded that applying the aforementioned doses of fertilizers combination would enable farmers increase productivity of groundnut so as to enhance farmers’ income and livelihoods.
Farm health and safety adoption through engineering and behaviour change
(2019) McNamara, J.; Griffin, P.; Phelan, J.; Field, W.E.; Kinsella, J.
The agriculture sector is one of the most hazardous occupations worldwide. The EU farming population is predominantly self-employed, who are largely outside the scope of EU occupational safety and health (OSH) legislation. Utilising effective communications approaches to transmit clear messages is a possible way of motivating farmer OSH adoption. The Public Health Model (PHM) of accident causation conceptualises an accident as occurring due to multiple interacting physical and human factors while the Social-Ecologic Framework enhances the PHM by defining various levels of the social environment which are influential on persons’ OSH actions. A knowledge gap exists in how farmers conceptualise accident causation. The aim of this study is to report findings of a Score Card exercise conducted among Irish farmers (n = 1,151) to reveal knowledge on farmers’ conceptualisation of accident causation where farmers ranked in order of importance up to five causes of farm accidents. First ranked items related to ‘machinery/ vehicles’, ‘organisational’ and ‘livestock’ as accident causation factors (92%). Overall rankings for up to five ranked causes identified six causes: ‘machinery/ vehicles’, ‘organisational’, ‘livestock’, ‘slurry related’, ‘trips, falls, buildings-related’ and ‘electrical’ (96.5%). The study data indicated that farmers’ perceptions of accident causes were inaccurate when compared with objective fatal farm accident data. The study concluded that communicating accurate and contemporary OSH messages to farmers has potential to assist with farm accident prevention. Based on the multiple and interacting risk factors arising in agriculture it is suggested that more elaborate study of farm accident prevention is warranted.
Reduction of moisture and thermal conductivity of wet walls by special plaster
(2019) Topol, M.; Kic, P.; Neuberger, P.
This paper is focused on the problems of moisture reduction in old buildings. Wet walls are very common problem of old buildings, but it can appears also in new buildings as well. The moisture in the wall influence the insulation quality; bigger heat losses continuously cause problems of worse heat balance, higher consumption of energy for heating and it can result in not sufficient indoor conditions in such a room or building. Old rural residential buildings and also agricultural buildings for housing of animals, storage of different materials, workshops etc. could be repaired and reconstructed by the used of some special methods. The application of special plaster can reduce the walls moisture as well as improve the thermal properties of the buildings by reduction of thermal conductivity. This paper includes the results of laboratory experiments focused on research of plaster properties (temperature, moisture and thermal conductivity) and tests provided in the real building. Different measuring principles, enabling mutual comparison of results were used for this research. The measurement results showed a significant effect of high wall moisture on the heat losses. Differences between the walls improved by new tested plaster and old untreated walls are discussed in this paper. Obtained results from this measurements and findings may be useful for further research in this issue as well as for the practical solutions for similar problems in many old buildings.
Effect of concentrate supplementation on fattening performance and carcass composition of finished meat-goat kids
(2019) Aplocina, E.; Degola, L.
A study on the effective usage of the concentrated feed supplement to Boer meat goat kids was carried out within the framework of the project ‘Zootechnical and economic efficiency of feeding of fodder pulses to ruminant’s meat production’. Since the Boer goat breed in Latvia is still very rare, there is a lack of experience in the feeding and production of meat goat for better carcass traits and meat quality. This study was arranged in autumn period, using the Boer cross breed male kids born in 2018. In control group (OG) four kids were kept together with mothers till finishing and were fed by oats as concentrated feed supplement. In research group (BG) four goat kids were weaned from mothers and placed in shed to explain influence of mix of 85% of oats and 15% of fodder beans as protein supplement to the fattening outcomes. In the trial kids were weighed at the starting and ending of the trial. Carcass quality is assessed according to the European standard for the classification of carcasses of sheep, where EUROP letter designations have been used to denote musculature development, and the fat deposition level is indicated by numbers 1–5. The length of the carcass and the circumference of the hips were measured using the tape measure. The carcasses were analyzed by type of tissue: muscle, bone, fat. The fastest growing rate during the fattening period of 72 days was given to BG kids with a mean daily live weight gain of 72 g, while the OG kids achieved 69 g. After slaughter, the carcass yield of OG kids was from 42.5% to 51.4%, but for BG kids was 38.5% to 42.5%. The quality of the obtained carcasses was an average, and score for musculature was from R to P class, but the average score for fat deposition was from 2.25 to 2.75 points and higher fat cover was observed in BG kids. Higher proportion of lean meat (59.1%) and fat tissues (16.3%) were observed to OG kids, but higher proportion of bone (25.9%) was in BG kid’s carcasses. The consumption of concentrated feed for 1 kg of live weight gain indicates the conversion of feed nutrients. The consumption of oats per kilogram of live weight gain was 3.21 kg for OG kids, but the consumption of the feed mix of oats and beans for BG kids was 2.83 kg. Based on physical parameters of goat kid carcass and high level of lean meat, fattening of Boer cross breed goat kids by using of oats or feed mix can be an ideal choice for farmers, which try to find new products and free market for consumers.
Influence of organic and inorganic fertilization on soil properties and water infiltration
(2019) Stehlík, M.; Czako, A.; Mayerová, M.; Madaras, M.
Soil aggregate stability (SAS) belongs to the most important parameters determining the quality of soil and fertilizer influence on soil aggregation. We evaluated the relationship between SAS, hydro–physical soil properties and infiltration rates in three long–term field experiments founded in 1956 on different soils. Soil properties under three fertilization regimes– no fertilization, farmyard manure, farmyard manure and mineral fertilization–were evaluated at silty loam Chernozem, silty loam Phaeozem and sandy loam–loam Cambisol. A significant impact of fertilization on SAS was found, even though the differences in SAS were rather low. The lowest SAS was recorded at plots with manure and mineral fertilization (25.1%) compared with plots without fertilization (28.7%) and plots with manure–only fertilization (28.2%). The highest SAS (36.5%) and the highest semi–capillary porosity (SP; 11%) were observed at sandy loam–loam soil. Hydro–physical soil properties were more favourable at fertilized plots (SP 9.6% and bulk density ρb 1.31 g cm-3 ) compared with unfertilized ones (SP 8.8% and ρb 1.35 g cm-3 ). The lowest SP (8.32%) and the highest ρb (1.37 g cm-3 ) were recorded at Phaeozem, which corresponded with the lowest SAS (19.4%). Chernozem had similar soil texture to Phaeozem, but SAS (24.7%), SP (9%) and ρb (1.27 g cm-3 ) were more favourable. Despite the low level of statistical significance due to the large variation of infiltration measurements, a higher infiltration rate was recorded at fertilized plots (45 mm hour-1 ) compared to unfertilized ones (35 mm hour-1 ).
Assessment of wild plants for phytoremediation of heavy metals in soils surrounding the thermal power station
(2019) Murtic, S.; Jurkovic, J.; Basic, E.; Hekic, E.
The present investigation was carried out to evaluate the phytoextraction potential of three main wild plant species: annual nettle (Urtica urens L.), daisy fleabane (Stenactis annua (L.) Ness.) and yarrow (Achillea millefolium L.) that grow spontaneously in heavy metal contaminated areas near the thermal power station in Kakanj, Bosnia and Herzegovina. Analyses of the heavy metal content (Ni, Fe, Cr, Cu, Zn, Cd, Pb, Mn) in soil and plant samples taken from the examined area were performed using atomic absorption spectrophotometry. The results obtained revealed that the examined soils are polluted by Ni and Pb and contain relatively high value of Cr and Fe. Annual nettle, daisy fleabane and yarrow have not shown high efficiency in the absorption and accumulation of heavy metals from polluted soils, and therefore these plants are not be considered as potential phytoremediators of soils on the examined area. Furthermore, the results of the study undoubtedly confirm the fact that the total content of heavy metals in soils is not a sufficient parameter for estimating the toxicity of heavy metals in soils and consequently for their transfer and accumulation in plants.
Possibilities for the biological control of yellow rust (Puccinia striiformis f. sp. tritici) in winter wheat in Latvia in 2017–2018
(2019) Feodorova-Fedotova, L.; Bankina, B.; Strazdina, V.
Yellow rust, caused by Puccinia striiformis f. sp. tritici, is a significant wheat disease worldwide. In Latvia, the distribution of yellow rust has increased recently and new aggressive races have been identified. The aim of this research was to investigate the possibilities for the biological control of yellow rust in winter wheat. A field trial was established in a biological field of winter wheat in Latvia in 2017 and 2018. Biological products that contained Bacillus spp., Pseudomonas aurantiaca, Brevibacillus spp., Acinetobacter spp., and chitosan were used for treatments, and one variant was left untreated. The efficacy of products was evaluated by the AUDPC (area under the disease progress curve) comparison. Differences in the severity of yellow rust between the trial years were observed. In 2018, the severity of yellow rust was lower than in 2017. In untreated plots, on flag leaf, the severity varied from 10.9% to 32.5% in 2017 and from 1.4% to 6.5% in 2018. In 2017, the severity of yellow rust reached its maximum on 05.07. at wheat growth stage (GS) 79, and in 2018 – on 20.06. GS 79. Both in 2017 and 2018, no significant differences (p > 0.05) were found in AUDPC values among the variants. After two years of investigations, the results were not convincing; therefore, further research is needed.

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