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Response of Pulses to Seed or Soil Application of Rhizobial Inoculants

Abstract

In micro-plot experiments growth, nodulation and seed yields of pea, yellow lupine and soybean grown in a soil colonized by high populations of pea and lupine rhizobia and low population of soybean rhizobia as influenced by seed or soil application of rhizobial inoculants were studied. The studied inoculation method had no significant effects on root nodule numbers, plant growth at the flowering stage and on seed yields of pea and yellow lupine in comparison to uninoculated control treatments. In the case of soybean seed and soil inoculation with soybean rhizobia (Bradyrhizobium japonicum) resulted in a significant increase of nodulation intensity, fresh and dry mass of shoots at the flowering stage as well as pod numbers and soybean seed yields at harvest. Soybean grown on plots in which soil was inoculated with the symbiotic bacteria gave seed yield by about 57 % higher as compared to that of soybean grown from seed inoculated with the rhizobia and by 169 % higher than when this crop was grown on the control (uninoculated) plots.

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Surfactants in Klodnica River (Katowice, Poland). Part II. Quaternary Ammonium Compounds

Abstract

The paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative determination of analytes phase - ion chromatography technique (combined with a conductivity detector (CD)). The determined concentrations were in the range below the determined method detection limit (MDL) or method quantification limit (MQL) figures up to 0.142 ±0.023 mg/dm3 or 2014 ±10 μg/kg (liquid and solid samples, respectively). Comparing concentrations of individual analytes found in liquid and solid environmental samples we may notice that surfactants containing a shorter alkyl chain in their molecules were found in higher concentrations in liquid samples (hydrophobicity increasing with the chain length).

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Sustainability of Waste Materials in Affinity with Ecologically Sustainable Development: A Case Study of Kosovo

Abstract

Using our natural resources, we produce much waste that can be recycled as a useful resource, which further contributes to climate change. Kosovo, generally produces a huge amount of waste, particularly Prishtina as the capital its capital city. The study presented in this paper investigated the high-rise buildings in Ulpiana neighbourhood of the city of Prishtina and waste disposals in Kosovo, focusing on the challenges of urban waste management, particularly on the recycling of high-rise urban generated waste. The research methods consist of empirical observation through urban spatial zone. Researched model of high-rise buildings, surveyed the land use, and recycling process of a total generated waste of 778.8 kg daily/per one structure. According to the conceptual and calculated findings strengthened with awareness for sustainable consumption, and proper urban strategy for implementing the recycling waste materials, it is indicated that the waste amount can be decreased and recycled for about 25 % from the total waste generated daily.

Open access
The Variability of the Concentration of Bioaerosols Above the Chambers of Biological Wastewater Treatment

Abstract

The article presents the results of research over microorganisms (psychrophilic and mesophilic bacteria and microscopic fungi) found in wastewater in denitrification and nitrification chambers and specifies the proportion of these microorganisms in bioaerosol at various levels above wastewater level (20, 50 and 100 cm). In the denitrification chamber (anoxic) in 1 cm3 of sewage there were on average 30.35 · 106 CFU of mesophilic bacteria, 72.88 · 106 CFU of psychrophilic bacteria, and 37.3 · 105 CFU of microscopic fungi. In the nitrification chamber, where the oxygen concentration ranged from 0.37 to 2.32 mg O2·dm−3 of wastewater, the number of microorganisms was lower. In 1 cm3 of wastewater there were on average 20.2 · 106 CFU of mesophilic bacteria, 51.76 · 106 CFU of psychrophilic bacteria, and 15.22 · 105 CFU of microscopic fungi. In sewage bioaerosols above these chambers, higher numbers of psychrophilic bacteria than mesophilic ones and microscopic fungi were reported. At the same time differences in the number of microorganisms at different heights above the surface of wastewater could be observed in bioaerosol, as well as between the chambers of the bioreactor. It was found that most frequently the amount of microorganisms decreased with height. The percentage emission ratio (ER) of microorganisms in bioaerosols coming from wastewater accounted for only a fraction of a percent and ranged from 1.13 · 10−8 % (microscopic fungi over the denitrification chamber) to 24.53 · 10−9 % (psychrophilic bacteria over the denitrification chamber). It was found that the process of mixing, aeration of wastewater, have an effect on the emission of microorganisms.

Open access
Alleviation Effect of Selenium on Manganese Stress of Plants

Abstract

Mn, as Fe, Zn, Cu and Ni is a heavy metal and also a necessary element all the living organisms. Excessive Mn nutrition causes a strong oxidative stress. The aim of the studies was to determination the effect of Se treatment (as sodium selenite Na2O4Se3) to alleviate the Mn stress of plants. Because of its sensitivity to oxidative stress induced by excessive concentrations of Mn a model plant was lettuce (Lactuca sativa L. ‘Sunny’). The studies were conducted in a controlled environment growth room in stable climate conditions: 16 h photoperiod; temperature light/dark 18.0 ±0.5°C/16.0 ±0.5°C; relative humidity 70-80%; quantum flux density 195-205 μmol m−2 s−1. Plants were grown hydroponically in nutrient solution characterized by excessive Mn content (19.2 mg dm−3) and different contents of Se (control; 0.77, 1.05, 1.33 mg dm−3). In all the combination were also tested different foliar sprays (distilled water and a 0.005% Se solution). Plants grown under conditions described above take up and transported Se from nutrient solutions into their leaves with a significant reduction of Mn concentration and changes in the plant nutrient status. With the increase in the concentrations of Se clearly narrowed quantitative relations in the leaves between this element and micro-metallic. Increasing Se levels in nutrient solution has a positive influence on the growth of plants, but Se foliar treatment generally decreases plant yield. The study shown that Se application may lead to alleviation of Mn stress of plants, with simultaneous reduce in Mn concentration in leaves - which may be of practical importance also in the cultivation of more economically important species.

Open access
Antioxidant Phenolic Compounds in Salvia officinalis L. and Salvia sclarea L.

Abstract

The differences in the chemical composition of the phenolic compounds of Salvia officinalis versus Salvia sclarea growing in different habitats, were studied. First, the optimal solvent - methanol - for ultrasonic extraction of phenolic compounds from these plants was chosen experimentally. Total phenolic content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. Total phenolic content was in the range of 63.9 to 134.4 mg GAE/g of plant depending on the studied species. The highest antiradical activity was displayed by the methanol fractions of S. sclarea varieties (83 and 67%). HPLC-DAD analysis of extracts was done in order to identify the presence of individual phenolic compounds. This was done by comparison of their retention times with those observed for 17 commercially available standard compounds. The results showed differences in the phenolics composition, with plants collected on Crimean peninsula accumulating more phenolic acids than Polish varieties. In turn, the Polish varieties of sage contain bigger amount of flavonoids in their tissues.

Open access
Computer Simulation of Chemical Coagulation and Sedimentation of Suspended Solids

Abstract

The computer program ZB2 was used to study simulated coagulation rate for the system containing spherical sol particles and spherical coagulant particles. The system performance was verified to the particle-cluster model of a fast and perikinetic coagulation process that fulfils Smoluchowski and/or Muller equations. The rate of the coagulation process satisfied both the kinetic equation of a first-order reaction and a second-order reaction. However, chosen concepts and models in the theory of bidispersive sol coagulation have been negatively verified. Also, attempts have been made to modify the Muller integral equation for selected boundary conditions.

Open access
Effect of Nanoaquacitrates on Physiological Parameters of Fodder Galega Infected with Phytoplasma

Abstract

The laboratory experiments have been found that soaking seeds Galega orientalis L. (Fodder galega) in nanoaquacitrates solutions of Mn (10 and 20 mg/dm3), Mo (4 mg/dm3) and Mg (2 and 4 mg/dm3), has been lead to germination energy rise, while Mn (10 and 20 mg/dm3) and Mo (4 mg/dm3) concentrations has been influenced germinating ability. At the same time, the soaking seeds in solution of nanoaquacitrates Mn (20 mg/dm3) had the biggest stimulatory effect on the accumulation 7 daily sprouts mass (on 18%). It has been shown that soaking seeds in nanoparticles Mn and Mo solutions leads to the increase of catalase activities (especially under the influence of manganese) and peroxidase activities (under molybdenum influence). Applying the method of chlorophyll a fluorescence in the field and greenhouse experiments with Galega orientalis L. plants, artificial infected with phytoplasma Acholeplasma laidlawii var. granulum st. 118 the following changes in the photosynthetic apparatus has been indicated: reduction in the length of the light-antenna, blocking transport of electrons in plastoquinone pool PSII with reducing the pool of electron acceptors. It has also been indicated that photochemical activity resistance of the photosynthetic apparatus decreases while its stability increases, as result of described above effects the concentration of chlorophyll a and b in plants leaves decreases. The above-mentioned negative effects have been deactivated through foliar treatment of infected Galega orientalis L. plants with nanoaquacitrates solution Mo (4 mg/dm3) that allow increasing of photochemical resistance of photosynthetic apparatus as well as chlorophyll content in leaves. The foliar treatment with Mn (20 mg/dm3) solution of the infected plants, in compared with infected plants without treatment, resulted in more significant increase of Ki value (which correlate to the ribulose-1,5-bisphosphate carboxylase/oxygenase activity), which is explaining anti-mycoplasma effect of this solution.

Open access
Effects of Silicate Fertilizer on Seed Yield in Timothy-Grass (Phleum pratense L.)

Abstract

A field experiment was conducted in the years 2012-2014, at the Plant Breeding Station in Polanowice near Krakow (220 m a.s.l.). The aim of the study was to investigate the effect of silicon (Si) on seed yield and quality of timothy-grass (Phleum pratense L.) of “Egida” cultivar. A univariate field experiment in randomized block design was repeated four times, and the area of the experimental plots was 10 m2. The soil on the experimental plots was a loess derived haplic phaeozem of bonitation class I. The experimental factor was spraying with a silicon formulation in the form of Optysil® fertilizer at three doses: 0.2, 0.5 and 0.8 dm3·ha−1. During the growing season, the plants were evaluated for their height, leaf greenness index (SPAD) and general condition. After harvesting, the seed yield and quality were assessed. The study revealed a significant effect of silicon on plant height, general condition and yield and quality of the seeds. The plants treated with silicon showed lower infestation rate with pathogens and pests than the control ones. Foliar fertilization with the highest dose of the silicon formulation (0.8 dm3·ha−1) caused a significant increase in seed yield as compared with control. The effects were also satisfactory in the plants treated with the formulation at 0.5 dm3·ha−1. The seeds obtained from silicon-treated plants were bigger, as revealed by the weight of 1000 seeds, and exhibited higher germination ability than the control seeds.

Open access
Impact of the Solar Irradiation Angle on the Work of Modules with Spherical Cells - Simulation

Abstract

The main purpose of all PV modules is to convert solar energy into electricity, but in the era of building integrated photovoltaics, there are additional opportunities to use them. The use of them as a composite of architectural structures in the form of facade cladding, roofing, stained glass windows or noise barriers on highways, in addition to generating electricity embellish also the aesthetic value of the facilities. However, these atypical their use, cause that the modules should have quite different properties then in the traditional application, which is related to their unusual way of positioning. Particularly for structures such as the modules made of spherical cells with the two active planes of operation. The article presents a comparison of the results of simulation of module with two active surfaces containing spherical solar cells in an open space in relation to a typical flat photovoltaic module. A comparison of its work with different orientation and inclination. Article shows the basic difference in its properties occurring at some settings in relation to a typical module and makes predictions about its future use.

Open access