2018, Vol. 16, No. 5

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/5378

Sirvi

Nüüd näidatakse 1 - 20 32

Volatile combustible release in biofuels
(2018) Vitázek, I.; Majdan, R.; Mojžiš, M.
Plant biomass consists of varied materials. Biomass is used for different purposes, but it is most frequently burnt in modern combustion devices for heat production. The quality of solid biofuels depends on the total content of combustibles while the volatile combustible content affects the combustion process. The aim of the paper is to determine the exact content of the biofuel components by the means of the gravimetric method – namely volatile combustible, ash and moisture content – and to evaluate the process of volatile combustible release as a function of temperature during the experiment. The device Nabertherm L9/11/SW/P330 type with accessory was used to carry out the experiments. Various biofuel samples were examined, namely wood (9 kinds), wood cuttings and wood chips (2 kinds), pellets (4 kinds), sawdust (1 kind), compared to less traditional fuels (DDGS and RME – 2 kinds) and wood coal (1 kind). The tables and graphs present the experimental results, which allow evaluation of the components content in different biofuels and provide characteristics of the process of volatile combustible release in analysed fuels. Spruce wood without bark showed the highest content of combustible (99.89%). Sawdust of fruit trees contains the highest proportion of volatile combustible (93.978%) and releases the combustible at the highest rate (15.25 mg h-1).
Environmental risk assessment studies on new plant protection products which have been elaborated from coniferous tree bark
(2018) Jankevica, L.; Polis, O.; Korica, A.; Samsone, I.; Laugale, V.; Daugavietis, M.
Nowadays there are still various chemical pesticides being applied in the course of ensuring plant protection. Since 2010, we have been working on the development of new, environmentally-friendly plant protection products which will provide an effective tool against pathogenic fungi and bacteria which cause disease in crop plants. The specific aim of this study was to evaluate a risk assessment for new plant protection products that have been elaborated on the basis of coniferous tree bark. Various products were tested which are extracted during the processing of wood bark from pine (Pinus sylvestris L.) and spruce (Picea abies (L.) Karst.). Ethanol extracts were formulated and applied during these experiments. Two formulations, which showed anti-fungal activity in vitro and in field trials on fruit crops (involving strawberries and raspberries) were selected for the risk assessment studies. The impact was studied of formulation treatment on crop plants and soil biological activity, and the accumulation of residues of active substances in crop plants and soil. The application of new formulations did not show any negative effect on the chlorophyll content and the chlorophyll fluorescence of plant leaves. The results showed that pine and spruce bark extract formulations contain active compounds (coumaric acid, quercetin, epicatechin, and ferulic acid) within the range of 5.1–5.9 mg kg-1 and 11.1– 443.9 mg kg-1 respectively. The amount of active substances which were determined in most cases was higher in the spruce bark extract formulation when compared to the pine bark extract formulation. Our results confirmed the presence of active compounds – epicatechin, quercetin, and coumaric acid – in strawberry fruits which remained untreated and in those that were treated with spruce ethanol extract formulation. Untreated raspberry fruits contained all four active substances within the range of 81–5,300 µg kg-1. We observed a significant increase of coumaric acid and quercetin in raspberries after their having been treated with spruce bark extract formulation in a 2% concentration, P < 0.05, and did not find any negative impact for spruce bark extract formulations when used on soil microbial biomass.
Determination of the tension limit forces of a barley malt and a malt crush in correlation with a load size
(2018) Hromasova, M.; Vagova, A.; Linda, M.; Vaculik, P.
This article deals with determination of selected parameters of barley malt (whole grain and crushed grain). The barley malt is besides water, hops and brewer's yeast, one of the basic ingredients necessary for the production of traditional Czech pilsner type of beer. The aim of this research is to determine limit force and internal friction angle with depending on the size of the load. The assessed malt crush was produced using a 2-roller malt mill. The 2-roller malt mill is based on the principle of grinding the material in a milling gap between two milling rollers, which is a very commonly used production of the malt crush. By determining the tension limits of the barley malt and the malt crush in correlation with the load, we can obtain very important parameters that inform us of the bulk material behavior, particularly with respect to the storage method (storage shape, height of the stored material layer, and the removal method from the storage, etc.), and to the transport (route gradient, transport speed, etc.). The determination of the tension limits has a direct link with cohesion of the bulk material and thereby contributes to establishing of the basic parameters of the bulk material, such as - the friction angle. The measurement for the angle of internal friction determination were performed on a prototype device. The principle of measurement on a mobile prototype devices is, the upper square chamber slides down the lower square chamber. Barley malt (whole grain and crushed grain) were loaded from 100 g to 5,000 g. The results of measuring were statistically analyzed with software Statistica 12.
Analysis and forecast of performance characteristics of combine harvesters
(2018) Zubko, V.; Roubik, H.; Zamora, O.; Khvorost, T.
This article presents results of an experimental research of qualitative indicators of the modern combine harvesters (Case IH Axil Flow 8230, MasseyFergusonMFT7, JohnDeereS680i, ClaasLexion760, NewHolland CR9.80) used for winter wheat harvesting. Based on the results obtained, determination was made regarding the productivity of combine harvesters on the field, fuel consumption, and field conditions influence the grain loss and grain damage caused by a harvester. When conducting the experimental research of a combine's performance on the field a study of the effectiveness of the combine JohnDeereS680i was made on different modes. A program 'Machine Unit', designed by the authors, was used for the determination of productivity, fuel consumption and quality indicator for harvesting.
The characteristics of wheat collection samples created by Triticum aestivum L/Triticum spelta L hybridisation
(2018) Diordiieva, I.; Riabovol, L.; Riabovol, I.; Serzhyk, O.; Novak, A.; Kotsiuba, S.
The aim of our research was to create, analyzes, and systematise wheat collection samples for the selection of valuable initial forms, to involve them in breeding process, and to create new productive cultivars. For this purpose the hybridisation of soft and spelt wheat was carried out, along with an evaluation of the hybrids that were obtained, between 2006 and 2018 (F5–F10). A collection of wheat samples, containing more than a thousand numbered items, was formed from the obtained diversity of samples. The economically-valuable and morphological characteristics of newly-developed materials were analysed. According to the results of our research, we selected forms of spelt, soft wheat, and speltoid samples which have high levels of productivity and high gluten and protein contents in grains. Spelt wheat sample 1817 contains 45.2% gluten, 22.3% protein, and has a yield capacity of 6.55 t ha-1 . Soft wheat sample 1689 has 32.4% gluten, 15.8% protein, and a yield capacity of 7.19 t ha-1 . These samples were submitted for state scientific and technical expert evaluation in 2018. The created varieties of European spelt wheat and Artemisia soft wheat were included in the ‘State Register of Plant Varieties Suitable for Distribution in Ukraine’. The varieties, Artaniia and Artaplot, were submitted for state scientific and technical expert evaluation.
Split water application for a water supply reduction in Callistemon Citrinus pot plant
(2018) Militello, M.; Sortino, G.; Talluto, G.; Gugliuzza, G.
Irrigation management in Greenhouse Nursery Production (GNP) is based on empiric methods based on farmer personal experiences with over-irrigation results. The effects of irrigation volume and daily application were studied in a pot experiment carried out on rooted cuttings in a greenhouse The irrigation volume treatment was performed on Full and reduced Treatment. The treatment of water application was carried out with split supply and unsplit supply. The effects of the treatments were evaluated in terms of biomass accumulation and partitioning, leaf area, photosynthesis and stomatal response, chlorophyll content, and water productivity. Callistemon showed a good adaptation to the different treatments tested during the experiment. A positive relation was found between biomass accumulation and irrigation volume, moreover split water application increased plant Dry Weight. Therefore, the highest biomass accumulation was registered in full irrigation volume in split application treatment, and this behavior was confirmed by the photosynthetic rate. No statistical differences were found, in terms of Relative Water Content (RWC), between the treatments. Stem water potential and stomatal conductance values suggest in Callistemon an anysohidric water stress response behavior. Our results evidenced that, in Callistemon potted plants, an irrigation volume reduction is possible when a split application occurs during the daytime. A full irrigation volume amounts to10.8 L per plant during the trial period of 90 days while the reduced volume amounts to 8.2 L per plant. Therefore, an increased water productivity can be obtained if the daily water requirement is split on two applications during the daytime. Our results highlighted a possible reduction in environmental impact of Callistemon greenhouse pot production, through the 25% reduction of the volume irrigation.
Productivity, quality and economics of four spring wheat (Triticum aestivum L.) cultivars as affected by three cultivation technologies
(2018) Zargar, M.; Polityko, P.; Pakina, E.; Bayat, M.; Vandyshev, V.; Kavhiza, N.; Kiselev, E.
Managing farming inputs in wheat production technologies is an issue of paramount importance to attain optimum profitable production. To examine how varying the farming inputs affects the nutrients uptake and productivity of spring wheat (Triticum aestivum L.) cultivars and to determine the economic efficiency of various cultivation technologies, three-year field experiments were laid out at the Russian Research Institute of Agriculture, during the 2015–2017 growing seasons. Experiments were conducted once a year using randomized complete block arranged in a split plot experimental design with three replications, with the cultivation technology treatments (basic, intensive and high intensive technology) as the main plots, and spring wheat cultivars (Zelata, Lubova, Liza and Ester) as the sub-main plots. The highest grain yield (10.8 t ha-1), harvest index (42.9%), gluten content (39.45%) and gluten index (71.17%) observed for spring wheat cultivar Lubova with the moderate application of farming inputs as an intensive cultivation technology. Highest protein content (18.02%) was attained for both intensive and high intensive cultivation technology with the cultivar Lubova, and the highest 1,000 grains weight (46.32 g) was recorded by cultivar Lubova in basic cultivation technology. Applying moderate amount of inputs as an intensive cultivation technology resulted in highest wheat yield and net income.
The effect of starter cultures on the qualitative indicators of dry fermented sausages made from poultry meat
(2018) Zinina, O.; Merenkova, S.; Soloveva, A.; Savostina, T.; Sayfulmulyukov, E.; Lykasova, I.; Mizhevikina, A.
Changes in physicochemical, rheological and microbiological properties occurring throughout the ripening (on days 0, 7, 14, 21, and 28) of dry fermented sausages made from poultry meat were studied. The effect of starter bacteria on the microstructure and sensory attributes of dry fermented sausages has also been determined. The results of physicochemical analysis of dry fermented sausage shows no significant difference (P < 0.05) between the test (inoculated) and the control sausages in the protein, fat, moisture, salt, ash and nitrite content. However, the significant difference (P > 0.05) between the control and inoculated batches in lowering the pH level, changing the critical shear stress, growth of viable microorganisms, accumulation of amine nitrogen during ripening was established. The results show, that inculcation of starter cultures accelerates biochemical processes during fermentation and thereby provides the necessary functional and technological properties of minced meat. Sensory profiling showed a more significant (P < 0.05) acidic and spicy flavour and intensity of acidic and smoked meat aroma; and increased firmness and cohesiveness in inoculated sausage. The results of microstructural analysis showed that the dry fermented sausages that ripened with the starter bacteria (Lactobacillus curvatus, Staphylococcus carnosus, Pediococcus pentosaceus), differ from the control sample compacted as a thin surface layer which is formed during the drying, smoking and maturation, and that indicates more uniform moisture removal.
A comparative analysis of functional traits in semi-natural grasslands under different grazing intensities
(2018) Targetti, S.; Messeri, A.; Argenti, G.; Staglianò, N.
The reduction of traditional management practices is a major threat for the conservation of permanent grasslands in many European marginal areas. The ecological importance of grasslands is acknowledged by the European Habitats Directive 92/43/EEC (1992) which includes many natural or semi-natural grassland types, and by the growing attention of society towards functions and services provided by these ecosystems. Nonetheless, the efficiency of conservation policies is questioned also for the lack of local-scale information on trends and state of grasslands hampers the definition of local-tailored schemes. The main objective of this work is to assess the potential of a set of functional traits in discriminating between different management intensities and their capacity to describe the dynamics occurring in semi-natural grasslands. The research was carried out in a hilly area of Tuscany (Italy) on four grassland sites characterized by similar environmental features (soil, climate, topography), and by different management practices for 10 or more years. The survey concerned collection and analysis of different functional traits related to foliar features, litter and botanical composition. The functional traits were able to differentiate the four sites under different management practices, but their effectiveness was different. Results support the possibility to perform a rapid appraisal of grassland successional stages based on leaf functional traits of dominant species and by the assessment of presence of a reduced number of species among those occurring in the community.
Comparative characteristics of antioxidant capacity of some forage plants of the Baltic Sea Region (a case study of the Kaliningrad Region and Estonia)
(2018) Chupakhina, G.N.; Shansky, Merrit; Parol, Argaadi; Chupakhina, N.Y.; Feduraev, P.V.; Skrypnik, L.N.; Maslennikov, P.V.
In this paper, we investigate changes in the antioxidant levels (anthocyanins, leucoanthocyanins, catechins) and the total water-soluble antioxidants capacity in forage plants in relation to their geography, i.e. proximity to northern or coastal areas. We demonstrate that the antioxidant content increases in unfavorable conditions, being higher in plants growing closer to the sea and in northernmost plants. Thus, since the total water-soluble antioxidants capacity is influenced by ecological factors, it may be used as one of the indicators in complex environmental assessment.
Film agents as an effective means of reducing seed shattering in Festulolium
(2018) Obraztsov, V.; Shchedrina, D.; Kadyrov, S.
In the conditions of the forest steppe of the Central Chernozem region, methods were studied to reduce shatter losses in the pre-harvesting period for Festulolium during the period 2009–2011, applying the film forming agents, Elastik (0.8–1.2 L ha-1), Bifaktor (0.8–1.2 L ha-1), and Metylan Universal Premium (1.4–3.8 kg ha-1). The agents were used at seed humidity levels of between 60–65%. Following anti-shattering treatment, seed moisture content gradually decreased. The application of film forming agents prevented seed shattering, and seeds were harvested by direct combining at a humidity of between 20–25% without heavy losses being suffered. Moreover, decreased seed losses due to film forming agents significantly reduced the cost of seed heap drying. In the control treatment, the seed yield amounted to 214.8 kg ha-1, and 360.7 kg ha-1 was lost as a result of natural seed shattering in the process of ripening. The Elastik and Bifaktor preparations prevented seed shattering and contributed to the preservation of a seed yield of between 522.1–563.5 kg ha-1. The application of film forming agents contributed to a reduction in losses during harvesting within the range of 9.7–16.8%. Application of the Metylan Universal Premium glue in the studied doses provided a significant increase of seed yield. The highest seed yield (490.1–495.2 kg ha-1) was obtained in the treatment which used a Metylan application at a dose of 3.0–3.4 kg ha-1, where seed shattering was reduced by 14.8–17.6%.
Particle size distribution analysis of pine sawdust: comparison of traditional oscillating screen method and photo-optical analysis
(2018) Chaloupková, V.; Ivanova, T.; Muntean, A.
Particle size and particle size distribution (PSD) are crucial parameters which affect properties of particulate and agglomerated materials, and have an impact on a quality and utilization of a final product. The aim of this paper was to determine PSD as well as to assess dimensional features of pine sawdust fractions via mechanical sieve analysis and photo-optical analysis. The first one is a traditional and standard method taking into account only one parameter of particle shape and the second one is a modern method based on a digital image processing that considers also irregular shapes of biomass particles. Pine sawdust was grinded into three fractions: 4, 8 and 12 mm and analysed using two mentioned methods. A horizontal vibrating sieve shaker comprising 11 sieves and a bottom pan was used, and the obtained data of retained particles on each sieve were evaluated. For comparison, a computerized photo-optical particle analyser was applied with max Feret’s diameter as a measurement algorithm for a particle length, and PSD was analyzed by grouping the particles according to their distinct lengths adjusted to the sieves’ sizes used in the screening method. Moreover, additional results in dimensions and parameters of PSD were obtained and evaluated through the photo-optical method. Pine sawdust particles can be described as non-uniform, mainly prolonged, finer particles dominated in all fraction samples. The study showed differences in the results, inaccuracy and other drawbacks of the conventional sieving method such as clogging and falling-through phenomena as well as the limitations of the machine vision. Strong sides of both methods were discussed, too. Overall, the results contributed to a better knowledge of the material properties and different methods of PSD analysis.
The effect of soil conditioner on the spatial variability of soil environment
(2018) Urbanovičová, O.; Krištof, K.; Findura, P.; Mráz, M.; Jobbágy, J.; Križan, M.
The aim of the study was to assess and evaluate the effect of soil conditioner on the spatial variability of soil environment. Activator PRP-SOL conditioning soil properties was selected as a field of study. Assessment of soil environment was done through the evaluation of selected soil properties, namely, tensile resistance of the soil and soil infiltration ability. Two dose of PRP-SOL application was done twice in year 2015 (Autumn and Spring) and once in 2016 (Spring) with application rates 150 kg ha-1 and 140 kg ha-1 , respectively. The area was divided into blocks where stimulators were applied and none treated as a control. The evaluation of recorded values showed that treatability and tillage itself was significantly better on the area which was treated by application of PRP-SOL activators. In addition, tensile resistance was decreased by 5.71% in comparison with non-treated area of experimental field. Since the infiltration ability is among the very important soil properties which have an effect on soil moisture regime as well as surface runoff and therefore soil erosion. The evaluation of recorded values has revealed the effect of treatment by PRP-SOL activators on soil infiltration ability and therefore it results in increases infiltration of precipitation as well. Overall increase of infiltration was recorded at value 2 mm h -1 . It can be concluded that application of soil activators may increase the soil conditions and therefore not only conserve soil fertility but even increase it from the long term perspective.
Can sustainability match quality citrus fruit growing production? An energy and economic balance of agricultural management models for ‘PGI Clementine of Calabria’
(2018) Di Vita, G.; Stillitan, T.; Falcone, G.; De Luca, A.I.; D’Amico, M.; Strano, A.; Gulisano, G.
This paper analyses energy and economic balances for different growing methods (conventional, integrated and organic cultivation) for Protected Geographical Indications (PGI) Clementine of Calabria, a quality-oriented citrus species in South Italy. Through a double methodological approach, the economic and energy sustainability of each production system was assessed by accounting for the farm net value (FNV) of farms. The energy employment in terms of direct (D) and indirect (I) sources and in terms of renewable (R) and non-renewable (NR) energy sources was also analysed. Regarding FNV, the results show that in the presence of European subsidies, organic farming (with 6.06 k€ ha-1) is more profitable than other systems (4.33 k€ ha-1 for integrated farming and 4.99 k€ ha-1 for conventional farming) due to the higher sales price of organic PGI clementines, which allow producers to obtain the highest remuneration for their capital (1.65 B/C organic, 1.48 B/C integrated, 1.61 B/C conventional). In addition, from an energy perspective, the organic farming systems showed better performances than conventional and integrated systems because they required the lowest average energy employment (49.5 GJ ha-1 year-1) compared with the integrated (57.2 GJ ha-1 year-1) and conventional scenarios (59.1 GJ ha-1 year-1).
Effects of Dormex (Hydrogen Cyanamide) on the performance of three seedless table grape cultivars grown under greenhouse or open - field conditions
(2018) El Masri, I.Y.; Rizkallah, Jad; Sassine, Y.N.
Greenhouse cultivation of table grapes is still limited to some experimental trials at Lebanese coast. One major constraint facing this type of cultivation is the lack of enough chilling hours causing irregular bud - break and yield reductions. Dormex, with Hydrogen Cyanamide as active ingredient, is an effective mean for dormancy release adopted in warm winter regions. The work investigated separate and combined effects of two factors: greenhouse cultivation and Dormex application on vine buds (following win ter pruning) on three - year old seedless cultivars (ARRA15, ARRA18, and ARRA19). Control consisted of non - treated plants grown in open - field. Results showed that Dormex application under greenhouse induced budburst uniformity, increased budburst percent (by 60%), number of flowers and fruits per shoot (by 83%) and vine productivity (by 90%) in all cultivars compared to control. Bud formation was increased under greenhouse and was reduced by Dormex treatment. Under greenhouse, elongation of current season sho ots was delayed and shoot length was reduced in treated plants, harvest was earlier by 7, 14, and 30 days in non - treated plants of ARRA18, ARRA19 and ARRA15 respectively and full fruit set (100%) occurred for all plants. Dry weight of shoots was improved b y Dormex application in both cultivation systems. All ARRA cultivars responded similarly to experimental factors except ARRA 19 under greenhouse where shoot length was enhanced in all plants while bud formation only in treated plants. Finally, treating vin e by Dormex under greenhouse was found as efficient tool to improve bud break and advance harvest under the specific Lebanese coastal conditions.
Identification of wet areas in forest using remote sensing data
(2018) Ivanovs, J.; Lupikis, A.
Aim of this study is to evaluate different remote sensing indices to detect spatial distribution of wet soils using GIS based algorithms. Ar ea of this study represents different soil types on various quaternary deposits as well as different forest types. We analyzed 25 sites with the area of 1 km 2 each in central and western part of Latvia. Data about soil characteristics like thickness of pea t layer and presence of reductimorphic colors in soil was collected during field surveys in 228 random points within study sites. ANOVA test for comparing means of different soil wetness classes and binary logistic regression analysis for evaluating the ac curacy of different remote sensing indices to model spatial distribution of wet areas are used for analysis. Main conclusion of this study is that for different quaternary deposits and soil texture classes different algorithms for soil wetness prediction s hould be used. Data layers for predicting soil wetness in this study are various modifications and resolutions of digital elevation model like depressions, slope and SAGA wetness index as well as Sentinel - 2 multispectral satellite imagery. Accuracy of soil wetness classification of soils on moraine, fluvial and eolian sediments exceeds 94%, whereas on the clayey sediments it is close to 80%.
Experimental study of an improved root crop cleaner from admixtures
(2018) Bulgakov, V.; Ivanovs, S.; Nowak, J.; Bandura, V.; Nesvidomin, A.; Ihnatiev, Ye.
One of the ways to raise the quality of sugar beet harvesting is the use of improved digging tools that are able to dig out root crops from the soil without any loss and considerable damage, as well as cleaners of the heap from admixtures. Perspective are the root crop harvesting machines, built according to the modular principle, where, depending on the state of the beet plantation, the composition of the cleaning tools, and the kinematic and technological modes of their operat ion are determined. To carry out experimental studies, experimental equipment was made which, under laboratory and field conditions, made it possible to obtain qualitative separation indicators of the heaps of sugar beet roots with wide variation in the ra nge of kinematic and design parameters of the improved cleaner. As the results of the laboratory and field experimental studies showed, in each of the two stages of cleaning the beet heap, a sufficiently high degree of removal of the soil admixtures and pl ant residues is ensured. Thus, at the first, preliminary stage of cleaning, the removal of admixtures amounted to 65.5 – 75.8%. After the second, basic stage of cleaning, the transported heap contained no more than 1.9% of admixtures. The results of the laboratory and field tests indicate that the proposed design of an improved sugar beet root cleaner from admixtures is prospective.
The effect of herbicides on seed productivity of Festulolium
(2018) Obraztsov, V.; Shchedrina, D.; Kadyrov, S.
An artificially developed intergeneric hybrid Festulolium (+Festulolium F. Aschers, et Graebn.) is the best forage crop with high energy and protein nutrition value which can be used for green fodder when creating cultural haylands and pastures. The advantages of this crop are high regrow capacity, high content of sugars and good winter hardiness. Wide use of this new crop in fodder production is constrained, firstly, because the crop is yet new and little known and, secondly, because there is a lack of seeds due to imperfections in the production technology. There are still very few scientific studies on the biology and technology of Festulolium cultivation in the forest-steppe of the Central Chernozem Region of Russia. In our works we were the first to study the biological features of Festulolium and develop the main technological methods of growing and harvesting its seeds. The work was carried out in long-term studies of the Department of Crop Science, Forage Production and Agricultural Technologies of Voronezh State Agrarian University in 2009 2011. The soil in the experimental plot was leached medium loamy chernozem. The experiments involved the VIK-90 Festulolium variety with the preceding crop being the vetch-oat mixture harvested for green fodder. The soil preparation was conventional for seed herbage of perennial grasses in the Central Chernozem Region. The associated records and observations were made according to conventional methods adopted in the seed production of perennial grasses. A high efficiency of the Aurorex (0.55 L ha -1 ) and the Dicamba (0.15 L ha -1 ) herbicides in the suppression of annual and perennial dicotyledonous weed plants has been identified. The application of these herbicides has significantly reduced (by 40-73%) the weed infestation of seed herbage in the first year of vegetation and, as a result, has improved its structure and crop quality. The use of the developed agricultural techniques allows reducing the energy costs and receiving an average of 433 496 kg ha -1 of certified seeds.
Effect of nitrogen fertilization on sorghum for biomass production
(2018) Pannacci, E.; Bartolini, S.
Two field experiments were carried out in 2005 and 2006 in central Italy in order to evaluate the effects of different nitrogen (N) application rates (0, 50 100 and 150 kg ha-1 ) on flowering date, plant height, biomass production and partitioning (leaves, panicles and stems) and biomass quality of a sorghum hybrid (H133). Sorghum showed a high potential in terms of biomass production without N fertilization (18.5 t ha-1 of d.m. in 2005 and 26.6 t ha-1 of d.m. in 2006). The rate that maximized the biomass production was 100 kg ha-1 of N, increasing the biomass dry weight by 23.8% in 2005 and 18.8% in 2006, with respect to unfertilized sorghum; higher N rates are not advisable in order to avoid increasing fertilization costs and environmental impact without benefit of greater biomass production. The two highest N rates when combined with low water availability appeared to increase the rate of plant development, causing earlier flowering and increasing the percentage of panicles in total biomass. Higher heating value (HHV), lower heating value (LHV) and ash concentration of biomass varied among N rates, with values of HHV and LHV lower for unfertilized sorghum (17.6 and 16.7 MJ kg-1 d.m., respectively) than when N was applied (from 19.0 to 19.7 and from 18.1 to 18.8 MJ kg-1 d.m., respectively); on the contrary, ash concentration was greater for unfertilized sorghum (7.5% d.m.) than for fertilized sorghum (from 5.8 to 6.7% d.m.). This research showed the high potential of sorghum in terms of biomass production also when cultivated with limited irrigation and fertilization inputs. The biomass dry yield obtained by one hectare of sorghum crop without N nitrogen fertilization (i.e. 22.6 t ha-1 of d.m., average of 2005 and 2006 values) produces the same energy, by thermal utilisation, of 9.3 toe, that is equivalent to energy produced by 10,385 L of diesel fuel or 11,097 m3 of methane fuel. This aspect increases the certainty of the energetic and environmental sustainability of sorghum crop.
Identification of yeast species involved in fermentation of the Kazakh camel dairy product–shubat
(2018) Nadtochii, L.; Orazov, A.; Kuznetsova, L.; Pinaev, A.; Weihong, L.; Garbuz, S.; Muradova, M.
In certain countries of the world, camel's milk is used for food on a level with cow's milk. Shubat is a traditional food product based on camel milk in Kazakhstan. It is a fermented milk product obtained as a result of spontaneous fermentation of camel's milk under the influence of native microflora. Received dairy product from the southern region of K azakhstan became the object of the investigation of the microflora of the fermented milk product shubat . The aim of the research was to study the microflora of camel milk, which causes its spontaneous fermentation. During the experiment, the dynamics of ac id accumulation by the change in active acidity (pH) and titratable acidity (°T) was studied. In addition to lactic fermentation fermented product ( shubat ), alcoholic fermentation was noted, which has given the finished product an increased acidity and a h igh degree of gassing. To enumerate and identify microorganisms, shubat was sown to the following nutrient media: MRS, Malt wort - agar medium at 36 °C and 30 °C respectively both for 3 days. We suppose that the dominant component of the shubat ’ s microflora was yeasts: Brettanomyces anomalus, Naumovozyma castellii . Pathogenic microorganisms, such as Salmonella, Shigella , were not detected during the research, considering that the shubat is formed as a result of spontaneous fermentation and has poor hygienic c haracteristics in comparison with pasteurized milk. Identification of individual strains of bacteria allows us to simulate a starter microflora for the production of a safe fermented product based on camel milk on an industrial scale in Kazakhstan. The ide ntified microflora, which causes spontaneous fermentation of camel milk and isolated strains of lactic acid bacteria, will make a significant contribution to the improvement of food safety in arid regions.

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