2021, Vol. 19, No. 3

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/7130

Sirvi

Nüüd näidatakse 1 - 20 27

Morphology of Camellia Sinensis L. leaves as marker of white tea authenticity
(Estonian University of Life Sciences, 2021) Durnova, N.; Simakova, M.; Isaev, D.; Simakova, I.; Simakov, A.
Tea is one of the most common drinks in the world. Classic tea is obtained by brewing the leaves of the Camellia sinensis L plant in hot water. However, even the leaves collected from the same branch of the same tea bush can have completely different anatomical, biochemical and taste characteristics. White tea is the youngest, immature apical leaves of the tea bush (fleshes) together with leaf buds (tips) which are is considered the most valuable parts of teaplant. The chemical composition of tea is studied in sufficient detail, however, there are still no uniform criteria for determining the authenticity of white tea leaves, which creates great preconditions for falsifying this most valuable type of raw material. The aim of this study was to study the macroand microstructure of white tea leaves from different manufacturers and to determine the morphological markers of the authenticity of white tea leaves. The objects of research were white tea from the Nandana Tea Factory (Sri Lanka) and white tea from an unknown manufacturer, purchased from a local tea shop. The study of raw materials was carried out in accordance with the requirements of GF XIV OFS 1.5.1.0003.15 ‘Leaves’ and OFS 1.5.3.0003.15 ‘Technique of microscopic and microchemical examination of medicinal plants and herbal medicinal products.’ The work was carried out on the basis of the laboratories of the Department of Food Technologies of FGBOU VO Saratov GAU named after N.I. Vavilov, and the Department of General Biology, Pharmacognosy and Botany, Saratov State Medical University named after V.I. Razumovsky Ministry of Health of Russia. Studies of the structure of white tea leaves from various manufacturers have shown that the structure and presence of morphological elements of leaves, such as hairs, stomata, leaf edge, druses, sclereids, differ markedly and can serve as reliable markers for identifying the variety of tea.
Woodworking wastewater biomass effective separation and its recovery
(Estonian University of Life Sciences, 2021) Vitolina, S.; Shulga, G.; Neiberte, B.; Reihmane, S.
The aim of the study was to develop a new Al-based hybrid coagulant that was effective in removing wood biomass from the wastewater formed in water basins of plywood plants during hydrothermal treatment of birch wood. The organic-inorganic coagulant was prepared by interaction of high molecular polyethyleneimine (PEI) with the inorganic polyaluminium chloride-based composite coagulant (KHPAC) in aqueous medium. Owing to the hybrid nature, the developed coagulant could simultaneously perform both the coagulation and flocculation function. The influence of a hybrid coagulant composition, its dosage, pH and a temperature on the efficiency of wastewater biomass separation was investigated. The best coagulationflocculation efficiency was achieved with the hybrid coagulant having a mass ratio of PEI/KHPAC equal to 0.3–0.5 and at the optimal dosage of 70–80 mg L -1 , reaching 97% yield of the total wood biomass and 60% yield of the lignin recovery. The efficient dosage of PEI and KHPAC in hybrid coagulant was about 1.4–1.8 and 1.7–2.2 times lower than if these coagulants/flocculants were used alone. As a result of the coagulation-flocculation process, wood biomass sludge is formed, which is a sufficiently large source of renewable organic matter, with the potential to obtain value-added products. The components of the biomass sludge were found to have surface activity and binder properties, as well as cation exchange capacity. Based on these properties, its ability to structure dusty soil particles with the formation of mechanically resistant soil aggregates was studied.
The biological basis for the use of acrylic hydrogel and protein growth stimulant in the soft wheat and triticale cultivation
(Estonian University of Life Sciences, 2021) Kolesnikov, L.E.; Uspenskaya, M.V.; Kremenevskaya, M.I.; Orlova, A.G.; Razumova, I.E.; Kolesnikova, Yu.R.
The development of technologies for the environmentally friendly biopreparations production and use including biopreparations based on acrylic hydrogel and protein growth stimulant, which is obtained by chemical hydrolysis from by-products of slaughtered animals processing is carried out as part of the optimization of the phytosanitary condition of wheat crops and creation of favourable agro-ecological conditions for its cultivation. An important feature of acrylic hydrogel is the ability to retain and release water to plants when needed. At the same time, protein hydrolysate can provide plants with an additional source of nitrogen which is a component of plant proteins, chlorophyll and it is necessary for normal growth and development of plants during the vegetation. The addition of the protein growth stimulant to acrylic hydrogel expands the potential application of Super Moisture Absorbent (SMA) due to the long-term growthstimulating effect on plants. The acrylic hydrogel and protein growth stimulant were added to the soil when wheat sowing in the certain concentrations and proportions. Wheat productivity was studied by the indicators complex, characterized the plants morphological features and the yield structure. Assessment of the degree of plant affection caused by pathogens was carried out both according to the generally accepted phytopathological indicator - conditional intensity of development, and using additional parameters. In the research, it was found that acrylic hydrogel and protein growth stimulant provide an increase in wheat yield and reduce the pathogens harmfulness. In combined application, they can be used in agriculture for wheat cultivation as a low-cost and environmentally friendly soil conditioner.
Identification of the effectiveness of associative rhizobacteria in spring wheat cultivation
(Estonian University of Life Sciences, 2021) Kolesnikov, L.E.; Belimov, A.A.; Kudryavtseva, E.Y.; Hassan, B.A.; Kolesnikova, Yu.R.
The maximum increase in wheat yield (by 67% to the control), associated with a decrease in the root rot development by 19%, an increase in the productive bushiness by 18%, the spike weight by 26%, in the grains number per spike by 8% was noted when using the Bacillus subtilis strain 124-11; the strain effect on leaf diseases was insignificant (2–5%). The plants differed in the maximum changes (to control) in the total bushiness by 59%, the plants vegetative part weight by 27%, the flag leaf area by 21%, the pre-flag leaf area by 28%, the roots numbers and weight by 20% and 62%. After plants treatments with the Pseudomonas fluorescens strain SPB2137, the wheat maturation period was reduced by 9% (to the control), wheat yield increased by 58% due to a decrease in the development of root rot and septoria by 18%, the yellow rust pustules area by 44%; the productive bushiness and plant height increased by 25% and 19%, the plant vegetative weight by 21%, the spike length by 4%. The most expressed protective and growth-stimulating effect was shown by the Sphingomonas sp. K1B, which caused a maximum decrease (to the control) in the root rot and yellow rust development by 22% and 7%, the strips length by 22%, the pustules number in the strip by 29%, brown rust by 10%, septoria by 11%. Wheat plants were characterized by a large number and length of roots by 17% and 13%, root weight by 49%, a maximum increase in the nodal roots number and length by 15% and 17%; total bushiness by 34.5%; a maximum increase in plant vegetative weight by 37%; the spike length by 3%.
Theoretical research into directional stability of trailed tandem- type disk harrow
(Estonian University of Life Sciences, 2021) Bulgakov, V.; Olt, Jüri; Nadykto, V.; Volskiy, V.; Polishchuk, S.; Aboltins, A.; Beloev, H.; Estonian University of Life Sciences. Institute of Technology
Disking is one of the methods of soil cultivation, provides its effective crumbling, loosening, partial mixing and soil inversion. This ensures that crop residues on the soil surface are shredded and intermixing with loosened soil particles. Since, in addition to crop stubble, weeds are also counted as crop residues, soil disking, along with the use of herbicides, is often regarded as the most effective method of controlling the weediness of the agricultural background. Despite the fact that numerous studies on the disk harrow working process are available, insufficient attention has been paid to the study of the stability of harrow machine-tractor units, especially trailed ones. The purpose of this study is to establish the theoretical patterns that would provide for selecting the trailed disk harrow parameters that ensure the desired directional stability of the implement, which, in its turn, helps to achieve the desired qualitative performance of the disk harrowing machine-tractor unit. The principles of the theory agricultural machine, analytical mechanics, higher mathematics, as well as methods of PC-assisted numerical calculations have been used. According to the results of the study, it has been established that sufficient directional stability of the trailed disk harrow can be ensured if its working width B, the distance from the hitch point to the centre of resistance (parameter d) and the operating speed 𝑉𝑜 are properly selected. Determining the above-mentioned parameters of the disk harrow with the use of the obtained new analytical relations ensures achieving just their optimal combination, which provides for the maximum field productivity of the harrow machine-tractor unit with the satisfactory stability of disk harrow movement in the horizontal plane.
Acoustic analysis of cement composites with lignocellulosic residues
(Estonian University of Life Sciences, 2021) Ferraz, P.F.P.; Abreu, D.H.S.; Huallpa, B.N.; Santana, L.S.; Cecchin, D.; Rabelo, G.F.; Rossi, G.; Barbari, M.
The concept of environmental sustainability has been seeking a way to develop projects that reduce the impacts provided by agricultural development and the excessive consumption of natural resources. However, there is still little knowledge about the acoustic insulation/absorption behaviour of lignocellulosic materials. Hence, this study aimed to evaluate the acoustic properties of five cement panels reinforced with the following lignocellulosic materials: eucalyptus, sugarcane bagasse, coconut shell, coffee husk, and banana pseudostem, which ones have as a reference a commercial plaster used as sealing in civil constructions. The proposed panels were produced with each lignocellulosic material residue. It was produced three replicates for each type including plaster (being 18 panels in total). The sound insertion loss (SIL) measurement of the above-mentioned panels have been performed using an acoustical treated inexpensive facility developed based on the literature. The characterization of the acoustic behaviour of the studied materials were analysed according to the IEC (61260-1). The acoustic measurements have been done in the range of 20 Hz to 20 kHz and the analysis in octave bands have been performed. To make the analysis easier, the overall range of frequencies mentioned above was divided as ‘low’, ‘middle’ and ‘high’ ranges. Additionally, the measurement of thickness, density and porosity structure parameters of the lignocellulosic samples have been performed. According to the results and doing a trade-off analysis, the eucalyptus presented the overall best performance considering the overall range of analysis, being the banana pseudostem and sugarcane bagasse materials as good competitors.
Application of pineapple fiber in the development of sustainable mortars
(Estonian University of Life Sciences, 2021) De Azevedo, A.R.G.; Rocha, H.A.; Marvila, M.T.; Cecchin, D.; Xavier, G.C.; Da Silva, R.C.; Ferraz, P.F.P.; Conti, L.; Rossi, G.
Due to the great worldwide increase in pineapple production, countries like Brazil and India have problems regarding the correct disposal of residues from the production of this fruit. One of the possibilities is the reuse of these residues in the form of fibers in cementitious materials, as is the case with mortars. As a result, the objective of this work is to evaluate the application of pineapple fibers in mortars in the proportion of 1: 4 (cement: sand) with addition of fiber treated in NaOH in the proportion of 3 and 6%. The properties of mechanical resistance, water absorption, mass density and adhesion were evaluated, aiming to apply the mortar in coatings of rural environments. The results indicate that the fibers reduced the mortar density and increased the mechanical strength. However, there was a reduction in adherence, especially with the use of 6% fiber, in addition to an increase in water absorption. Based on the results, it is concluded that it is feasible to use 3% of pineapple fiber for the production of coating mortars in rural environments because the results obtained in the investigation are compatible with this application and with the established normative limits.
Comparison of spatial-temporal analysis modelling with purely spatial analysis modelling using temperature data obtained by remote sensing
(Estonian University of Life Sciences, 2021) Dos Santos, L. M.; Ferraz, G.A.S.; Alves, H.J.P.; Rodrigues, J.D.P.; Camiciottoli, S.; Conti, L.; Rossi, G.
Variations in climatic elements directly affect the productivity of agricultural activities. Temperature is one of the climatic elements that varies in space and time.Therefore, understanding spatial variations in temperature is essential for many activities. Given the above, the objective of this work was to compare the performance of the proposed spatiotemporal analysis model with that of purely spatial analysis using temperature data obtained by remote sensing. The experimental data were arranged in a grid with 403 spatial locations, with 22 samples collected in a 24-hour period. The statistical software R Core Team (2020) was used to perform the analysis. The packages used in the analyses were ‘geoR’, ‘CompRandFld’, ‘scatterplot3d’, and ‘fields’. For making the maps, the software ArcGIS was used. The behavioural analysis of spatiotemporal dependence indicated, through the covariogram graph of the data, that there is a strong spatial dependence. For the cases of purely spatial analysis of phenomena, a separate spatial model for each time is justified because this type of model presents a smaller prediction error and requires simpler processing than the space-time model. It was possible to compare the space-time analysis with the purely spatial analysis using temperature data obtained by remote sensing images. The data modelled with the purely spatial analysis had, on average, lower error than those with the space-time model.
Slow-release fertilization and Trichoderma harzianum-based biostimulant for the nursery production of young olive trees (Olea Europaea L.)
(Estonian University of Life Sciences, 2021) Di Vaio, C.; Testa, A.; Cirillo, A.; Conti, S.
Valorization of local olive cultivars is a key factor for the medium-term development strategy of the Italian olive agroindustry. This involves enhancements in both, cultural practices and nursery techniques. The aim of this research was the evaluation in nursery, on vegetative growth and root development of young olive plants, of two different treatments: substrate enrichment with Osmocote®, a slow-release fertilizer, and Trianum-P a Trichoderma harzianum based biostimulant applied as foliar spray. The trial was carried out on Rotondella and Salella, two autochthonous olive cultivars from the Campania region (southern Italy). Central axis height, number and length of lateral shoots, leaf number and trunk base diameter were monitored during the experiment. Eight months later, all plants were uprooted, and further parameters were measured: total leaf area, trunk cross sectional area (TCSA), fresh and dry weight of the leaves, shoots, trunk, roots, and total dry matter. The canopy/root ratio (C/R) was also determined. Overall, the Osmocote® treatment caused a significant increase in the vegetative growth parameters for both cultivars, with a more evident effect on the development of the canopy organs. The observation reported in the present work can represent a convenient piece of information particularly in relation to stress resilience in nursery production.
Enrichment of the winter triticale gene pool under intergeneric hybridization
(2021) Diordiieva, І.; Kochmarskyi, V.; Riabovol, Ia.; Riabovol, L.; Serzhyk, O.
The purpose of the research was to expand the genetic diversity of winter triticale under intraspecific and remote hybridization and to obtain new valuable forms for their involvement in the breeding process of creating high-yielding crop varieties. For this purpose interspecific and remote hybridization of different species of wheat, rye, triticale, Elimus arenarius L. and evaluation of obtained hybrids were carried out from 2013 to 2020. According to the results of our research it is proved that the species Triticum spelta L. and Triticum petropavlovskyi Udacz. had dominant genes of incompatibility with rye. Crossing Triticum compactum Host. and Triticum sphaerococcum Perciv. species with rye allowed obtaining a higher level of seed setting, but the grain obtained with the participation of Triticum sphaerococcum Perciv. species was not viable. Compatibility of triticale with spelt and Elimus arenarius L. was low. The level of seed formation in F1 hybrids under artificial pollination was higher than under spontaneous pollination. Seed germination obtained from pollination of F1 hybrids by fertile forms of triticale - was low. It was found that hybridization of three-species triticale with spelt had a positive effect on grain quality indicators in the offspring. Crossing triticale with Elimus arenarius L. led to ear elongation, but caused a significant reduction in all indicators of grain quality in the offspring. As a result of remote hybridization of three-species triticale and spelt wheat, winter triticale varieties Navarra and Strateh were created and included in the State register of plant varieties suitable for distribution in Ukraine since 2018.
Biological effectiveness of a new multifunctional biopesticide in the protection of organic potatoes from diseases
(2021) Novikova, I.I.; Minin, V.B.; Titova, J.A.; Krasnobaeva, I.L.; Zaharov, A.M.; Perekopsky, A.N.
Crop disease control is of particular importance in organic crop production, as the use of chemical pesticides is prohibited there. A new multifunctional biofungicide Kartofin was selected and used to optimize the phytosanitary state of organic potatoes ecosystems. Previously of studies indicated the prospects of using the biofungicide to control numerous fungal and bacterial diseases during the potato growing season and storage of tubers. The crop rotation field experiment was carried out in 2017–2020 at the Experimental Station of the IEEP - BRANCH OF FSAC VIM near Saint-Petersburg (59°65 N and 30°38 E). The soil of experimental plots is sod-podzolic light loamy. In the potatoes (variety Udacha) field, a 2-factor field experiment was established which studied:  the action of biofungicide Kartofin;  the effect of the compost. The experiment was established on the plots with the size 61.6 m2 each. The experiment had four replications. Three doses of the compost were used which corresponded to different levels of the potato productivity. Potatoes were treated with biofungicide at the time of planting and by foliar spray during the growing season. The combined use of compost at a dose of 4 t ha-1 and biofungcide made it possible to achieve the yield of standard tubers of 27.3–28.2 t ha-1 with their low incidence of fungal diseases. The biological effectiveness of the biofungicide Kartofin in reducing the prevalence and development of a complex of fungal diseases (alternariosis, late blight, stem form of rhizoctoniosis) on potato plants of the Udacha variety reached 82.2–89.9%.
A justification of the choice of parameters for the picking reel tooth on a lowbush blueberry harvester
(2021) Arak, Margus; Liivapuu, Olga; Maksarov, V.V.; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
The functional working tool on the blueberry harvester is its rotating picking reel. Its working element is the picking rake which is attached to the picking reel. A total of four rakes are attached to the picking reel. A picking rake includes an axis which is attached in an articulated manner between the reel’s end discs, and pin-shaped teeth which are rigidly attached to it. The picking rake’s tooth must be made of a fully flexible material to prevent damage to the blueberry plant. The aim of this research was to determine the flexure of test specimens (plastic rods) which have been constructed from a fully flexible material of different conditions, along with the suitability for use of such flexible material as the teeth on the picking rake. As a result of this study, it became clear that, based on the results from flexure, durability, and residual deformation tests, it is more expedient to choose Ertacetal C (POM-C) as the material for the picking reel’s tooth, with a diameter of 4.3 mm.
Bibliometric analysis on the use of natural fibers in construction materials
(2021) Ferreira, G.M.G.; Cecchin, D.; Azevedo, A.R.G.; Valadão, I.C.R.P.; Costa, K.A.; Silva, T.R.; Ferreira, F.; Amaral, P.I.S.; Huther, C.M.; Sousa, F.A.; Castro, J.O.; Ferraz, P.F.P.; Teixeira, M.A.
Due to the increasing interest of the population in the sustainability theme, there was a consequent growth in publications related to the theme in the area of civil construction. Agroindustrial waste has become an environmental problem, and with that natural fibers have found space in the reuse of waste due to its characteristics and possibilities of improving the mechanical properties of its products. In order to achieve sustainable construction demand, along with the need to reuse waste, studies have begun to analyze the application of natural fibers in construction materials. The documents provided by the Web of Science (WOS) database through research carried out with the search for the terms ‘Natural Fibers’ and ‘Building materials’ restricted to the period 2010–2020 in the main WOS collection. The institutions involved with the publications, the countries of origin of the documents, the year of publication, the keywords used by the authors and the number of citations for each document were analyzed using bibliometrics in the VOSVIEWER (VOS) software. The result of the analysis shows an increase in documents related to the theme over the years, and that the countries with the most studies in the area are China (16), USA (14) and Brazil (11), respectively. The results presented after analysis of the keywords show that natural fiber (61 occurrences), mechanical properties (44 occurrences) and composites (31 occurrences) are the words with the highest occurrence among the analyzed documents. The present study shows the growth of research related to the theme, in addition to discriminating countries, institutions and authors, which allows monitoring the scientific expansion of the theme and guiding future studies.
Some mechanisms of winter resistance in apricot flower buds in the period of ecodormancy
(2021) Golubev, A.M.; Alyoshina, N.A.; Anfalov, V.E.; Kulikov, A.A.; Vdovenko, V.S.
The accelerated development of flower buds during the thaw in apricots and almonds during the ecodormancy period leads to significant damage to the flower elements during return frosts and loss of future crops. The aim of the research was to identify the mechanisms of delay in the rate of development of flower buds during the ecodormancy period, their relationship with the degree of frost resistance and the timing of flowering in apricots. The following indicators of flower buds were analyzed: the degree of exit from endodormancy, frost resistance at temperatures of -18 °C and -31 °C, the degree of morphological development of flower elements, the activity of α-amylases at temperatures of + 15 °C and + 60 °C, total content water, phenolcarboxylic acids, flavonoids and free proline. A significant positive correlation was revealed between the percentage of death of flower buds at a temperature of -18 °C and the percentage of buds emerging from endogenous dormancy (0.64*), the percentage of death of buds at a temperature of -31 °C and the degree of development of flower elements (0.70*), water content and the degree of development of flower elements (0.76**), amylase activity at +60 °C and amylase activity at +15 °C (0.76**), the content of phenolcarboxylic acids in the bark of shoots and flower buds (0.61*). For the first time, psychrophilic forms of α-amylases have been discovered in apricot flower buds.
Technical and economic pre-feasibility study for the construction of septic tank-filter-sinkhole with alternative material
(2021) Martins, P.H.N.; Cecchin, D.; Azevedo, A.R.G.; Carmo, D.F.; Danagemma, R.A.; Waite, R.M.M.; Rodrigues, N.F.; Sousa, F.A.; Amaral, P.I.S.; Hüther, C.M.; Pereira, C.R.; Cruz, V.M.F.
The study of the different materials used in the construction of septic tanks aims to facilitate and spread the use of this sewage treatment system in places that are not assisted by municipal sewage systems and in the rural area, which despite having a smaller number of inhabitants compared to the urban area This study aims to carry out a technical and economic evaluation of the concrete and tires using in the construction of septic tanks-filter-sinkhole. The wastewater treatment systems were built according to the recommendations in NBR 7229/93 and 13969/97. To evaluate the efficiency of each system built, the following parameters were analyzed: chemical oxygen demand (COD), the potential of hydrogen (pH), alkalinity, acidity, and temperature. In the economic evaluation, the materials and labor required to install the systems were considered using the Brazilian cost database (SINAPI), and an economic and financial feasibility study was carried out. According to the technical and economic analysis of construction, both systems showed the same technical performance, however, the concrete design proved to be more advantageous than the tire design, considering the difficulty in acquiring the tires and the high cost if it is necessary to buy them, in addition to the greater difficulty in handling and installing the tire system compared to the concrete one.
Marginal abatement cost curve for an ammonia reduction measure in agriculture: the case of Latvia
(2021) Lenerts, A.; Naglis-Liepa, K.; Popluga, D.; Kreišmane, Dz.; Aplociņa, E.; Bērziņa, L.; Frolova, O.
With the production of grain and livestock–derived agricultural commodities increasing, the agricultural sector has become one of the main sources of ammonia (NH3) emissions in Latvia. In 2018, the agricultural sector contributed to 83% of the total NH3 emissions originated in Latvia (15.46 kt) (LIIR 2020). The EU has already put in place measures to control NH3 emissions. This includes the EU target of reducing ammonia emissions by 21% by 2030 and sets out emission reduction commitments for Latvia. Considering Latvia’s indicative reduction target, the NH3 emission reductions need to be achieved by 2030 (Directive 2016/2284) so that the emissions do not exceed the 2005 level (11.33 kt). Implementing no mitigation measures, Latvia has projected agricultural sector NH3 emissions to be 32.4% higher than those in 2005, and therefore the mitigation of the NH3 emissions from agriculture is important. The research aims to estimate cost-effective NH3 emission reduction measures in agriculture in Latvia. The results of the research represent a marginal abatement cost curve (MACC) analysis, in which we have quantified the potential for reduction for selected NH3 emission mitigation measures in Latvia. A list of the measures has been established taking into account the experience of good agricultural practices in the reduction of NH3 emissions (UN, 2014) and of other European countries as well. The calculations carried out allowed us to group the measures according to their priorities: measures that are cost-effective and with high potential for reduction of NH3; measures that are cost-effective but with low NH3 emission reduction potential; measures that are not cost-effective but with high potential for reduction of NH3; measures that are not cost-effective and with low potential for reduction of NH3. The estimated cumulative (total) reduction of NH3 emissions in Latvian agriculture by 2030, with the implementation of the measures analysed, is equal to 20.08 kt.
Evaluation of artificial agricultural landscapes biodiversity in Stavropol Botanical Garden
(2021) Grechushkina-Sukhorukova, L.A.; Peshchanskaya, E.V.
The meadow steppes recreated in the Stavropol Botanical Garden, Russia, by planting sod blocks after more than 40-year period of cultivation have preserved species composition similar to zonal steppes. The aim of our research is to evaluate the restored artificial cultivated land biodiversity. A parallel measurement of species saturation per 100 m², yield, botanical analysis by crops was conducted on model experimental sites and in nature. Systematic and biomorphological flora study, analysis of variance were carried out. Useful plant species were identified. The restored steppes represent a multispecies community including 236 species, 149 genera, and 36 families. It consists of 5 biomorphs which comprise 2.9% of phanerophytes, 3.0% of chamephytes, 74.6% of hemicryptophytes, 14.4% therophytes that have a high degree of similarity in quantity to the steppes of Central Fore-Caucasus. The cenoses are dominated by plants having life cycles of perennial ones which accounts for 81.0%, annuals, and biennials make up 19.0%, cereals and sedges amount to 32 species (13.5%), legumes represent 28 speies (11.9%), mixed herbs are 176 (74.6%). The projective cover of grass stand is 80.0–100.0%, that corresponds 73–109 species per 100 m². An average yield of the restored steppes grass stand is 2.8–3.8 t ha-1 . It exceeds the productivity of natural cenoses by 2.1–3.3 t ha-1 . The botanical analysis by crops demonstrated that in the grass stands samples of cereals (19.6–43.9%) and mixed herbs (18.3–31.2%) dominated. 18 rare plants are preserved in the cenoses. 171 species have useful properties. The site of the restored meadow steppe is an exposition and serves for sightseeing and educational purposes. Lately, sod blocks planting was widely used in experimental phytocenology and landscape design. Its implementation for natural vegetation restoration on the large areas is time-consuming and expensive compared to the method of cultivated lands, therefore it can be used in small sites as a component of combined options.
Wheat cultivars exposed to high temperature at onset of anthesis for yield and yield traits analysis
(2021) Goher, R.; Akmal, M.
Temperature fluxes at some critical growth stages adversely affect the crop yield. Heat stress (HS) of limited duration shows mild to marked effects on crop yield. The study focused on evaluating HS of limited durations on wheat crop effective from anthesis. Four wheat cultivars (Pirsabak-2005, Pakhtunkhwa-2015, Pakistan-2013, and DN-84) and three advanced lines (P-2, P-12, and P-18) were subjected to HS for 48, 72, and 96 h evaluating changes in the yield and yield contributing traits. The experiment was conducted in a randomized complete block design during 2017–18 and 2018–19 at Agronomy Research Farm, the University of Agriculture Peshawar Pakistan. At the onset of anthesis, plants were exposed to HS in the plastic tunnel for limited durations. The temperature inside and outside tents was recorded periodically. The mean across the years showed a significant effect on yield traits by HS imposition at anthesis stage. The mean data across the two years showed a significant effect of HS on yield and yield contributing traits. In comparison with control, spike weight (g) reduced by 29, 40, and 49% under limited HS of 48, 72, and 96 h, respectively. Grains per spike were decreased by 45, 61, and 69% and grain weight by 29, 36, and 45% from control to imposed HS of 48, 72, and 96 h, respectively. Overall grain yield decreased by 44, 61, and 70% upon exposed to 48, 72, and 96 h of HS, respectively. The differences among the cultivars for yield and yield contributing traits were different under various HS conditions. The study concluded that HS effective from anthesis has an adverse effect on grain weight and number and hence the grain yield. Among the cultivars, Pakistan-2013 showed better resistance to HS of limited duration when exposed at the anthesis stage of the crop growth.
Suitability of various onion (allium cepa) varieties for drying and long-term storage
(2021) Zavadska, O.; Bobos, І.; Fedosiy, I.; Podpriatov, H.; Komar, O.; Mazur, B.; Olt, Jüri; Estonian University of Life Sciences. Institute of Technology
In the paper, the results are presented obtained in the research into the fresh bulbs and the dried products of 9 onion varieties cultivated in the conditions of the Ukrainian Forest Steppe area with regard to their economical biology, biochemical, marketability and organoleptic indices. The varieties that are most suitable for convection drying and long-term storage have been identified. It has been established that the marketability of both the fresh bulbs and dried products depends on the masses of the bulbs. The Bronze d’Amposta and Harmony varieties deliver the greatest amount of marketable output (94.0 and 93.2%) featuring marketable bulbs with masses of 67.4 g and 70.4 g, respectively (r = 0.82). As the bulb mass increases, the amount of non-standard (r = -0.81) and small (r = -0.76) particles in the dried product decreases substantially. It has been found that the content of solid matter and sugars in fresh bulbs has effect on the yield and quality of the dried and reconstituted products. The Harmony and Skvirskaya varieties, the bulbs of which during the vegetation season build up 12.9% and 13.8% of solid matter, respectively, are distinguished by the highest dry product yield - 17.1 and 16.8%, respectively. Correlation has been established between the contents of solid matter and sugars in fresh bulbs (r = + 0.58). During the tasting of reconstituted onion products, the highest scores were awarded to the samples produced from the Skvirskaya and Harmony varieties - 7.0 points each on the 9-point scale, as their bulbs had accumulated over 7.0% of sugars (total). Judging by the aggregate of the researched indices, the Harmony and Skvirskaya varieties of onions are the most suitable for convection drying. It has been established that the preservation of onions in the conditions of stationary buried storage without artificial cooling depends on the duration of storage and the specific varietal features. Within the five months of the test storage, the preservation of bulbs of all the varieties was high and varied within the range of 80–93%. Longer storage is expedient only in case of the Harmony, Skvirskaya and Gospodinya, for which the bulb preservation rates for a seven month storage period has been shown to be equal to 90.2, 88.4 and 87.2%, respectively. It has been proved that the quantity of healthy bulbs depends to a significant extent on the solid matter content in the bulbs (r = 0.93).
Concentrations of CO₂ from composting under different treatments
(2021) Karandušovská, I.; Hlinka, P.; Páleš, D.; Szabóová, T.
The aim of this study was to analyse the production of CO2 concentrations in relation to the composting technology used. Three loose piles of bio-waste (V1, V2, V3) were created with the same volume. V1 reference pile was without any treatment. The biological preparation containing probiotic bacteria was added to the pile V2. The pile V3 was treated once a week by turning and watering. The degassing shafts were installed in each pile and the Multigas Monitor 1312 gas analyser with the Multipoint Sampler 1309 were used to measure of gas concentrations during the degradation process. Continuous 24-hour measurements of carbon dioxide concentrations from each pile were performed in the first, fourth, and seventh week of the degradation process to compare the amount of concentrations between piles in those weeks. At the beginning of the process, there were no significant differences in the production of CO2 concentrations from the monitored piles V1, V2 and V3. In the fourth week, significantly higher values of CO2 concentrations were recorded from the pile V3 (P < 0.05), which was turned and irrigated, than from V1 and V2. At week 7, significant differences were found between all treatments at the significance level (P < 0.05), with the highest values from the V3 pile. It has been shown that turning and humidifying results in the highest release of CO2 into the air, but in a more rapid decomposition of the microorganisms, that reducing the time required to achieve a stable compost product and increasing the efficiency of the composting plant.

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