The present study was aimed at evaluating fluorine contamination of the eggs of free-ranging laying hens in Northern Poland, in the Central Pomerania region, in relation to the distance from the emission sources. Fluorine levels in the soil, feed, and the shells, and contents of the eggs were assayed with the potentiometric method using an ion-selective electrode from ORION Ion Meter. The sampled eggs were subjected to pressure microwave digestion with the use of a Milestone MLS-1200 microwave. All the samples were digested in 5 ml of supra-pure grade concentrated HNO₃ from Merck. The mean level of fluorine in the studied soils ranged from 3.79 mg kg⁻¹ of DM in typical river alluvial soil to 126.19 mg kg⁻¹ of DM in lessive soil. The study revealed an average fluorine content in the feeds administered to the hens on the farms in zone 1 (17.29 mg kg⁻¹ of DM), it being 3.5 times higher than the corresponding content in zone 2 (4.92 mg kg⁻¹ of DM). A statistically significantly higher mean fluorine level was identified in the eggshells of hens on zone 1 farms, located closer to the pollution emission sources (17.52 mg kg⁻¹ of DM), the value being more than 3-fold higher than that in zone 2 (5.47 mg kg⁻¹ of DM). The present study revealed an almost twice as high fluorine mean content in the hen eggs collected on farms in zone 1 (1.488 mg kg⁻¹ of DM) compared with the hen egg contents in the experimental zone 2 (0.640 mg kg⁻¹ of DM), the difference being statistically significant.

Background: The impact of light on the content of undesirable substances is particularly important in the case of potatoes available in store where the tubers are exposed to continuous light access. Both washed and unwashed potatoes are available, hence the hypothesis that the amount of harmful substances stored in tubers depends not only on the time of their exposure to light, but also on whether they were washed or not. Methods: In order to verify the hypothesis, laboratory tests were carried out on the tubers of five potato varieties originating from a univariate field experiment. The aim of the study was to analyse the change in the content of total glycoalkaloids (TGA) and nitrates (V) in tubers of five potato varieties depending on the time of light exposition (0, 7, 14 days) and pretreatment of tubers. Results: It has been demonstrated that the content of glycoalkaloids and nitrates in potato tubers depended significantly on the variety, time of exposure to light and pretreatment. Most glycoalkaloids were accumulated in the tubers of the Lord (89.67 mg·kg⁻¹) and Irga (89.05 mg·kg⁻¹) varieties. The time of light exposure significantly influenced the increase in glycoalkaloids and nitrates in the studied potato tubers. The increase in TGA after 14 days ranged from 20.67 mg∙kg⁻¹ for variety Vinieta to 54.67 mg∙kg⁻¹ for variety Irga. The increase in nitrates ranged from 11.67 mg∙kg⁻¹ for variety Bellarosa to 27.50 mg∙kg⁻¹ for variety Irga. Exposure time affected the content of glycoalkaloids in a parabolic manner and the content of nitrates in a linear manner.

Background: Soybean is one of major crop plants cultivated in numerous parts of the world, which is due to an increasing demand for plant protein. Both in Europe and Poland, much attention is paid to enhancing the production of their own fodder protein, as to reduce the import of soybean meal produced from genetically modified plants. Climate warming and breeding progress have made it possible to grow soybeans in central Europe. The yield potential of plants, including soybeans, can be enhanced by an application of biostimulants, which alleviate negative effects of stresses disturbing the life processes of plants. The objective of the present work was to evaluate, under the climatic conditions of central-eastern Poland, the yielding of three non-modified soybean cultivars treated with biostimulants. Methods: A field experiment was conducted in the years 2017–2019 in eastern Poland (central Europe). The soil of the experimental field belonged to the Haplic Luvisol group. The experimental factors included three non-GMO soybean cultivars (Abelina, Merlin, and SG Anser) and two biostimulants (Asahi SL and Improver). Results: Soybean seed yields were affected by the climatic conditions during the growing season, cultivars, and biostimulant applications. Regardless of cultivars and biostimulants, the highest yields were produced by plants grown in 2017 (on average, 3.41 Mg∙ha⁻¹), them being slightly lower in 2019 (on average, 3.0 Mg∙ha⁻¹) and the lowest in the dry 2018 (on average, 2.48 Mg∙ha⁻¹). Significant differences were recorded between cv. SG Anser (the average yield 2.73 Mg∙ha⁻¹) and Merlin (the average yield 3.31 Mg∙ha⁻¹). An application of biostimulants resulted in a significant increase in soybean seed yield compared with the control. Biostimulants contributed to a significant increase in the values of the remaining characteristics, i.e., 1000-seed weight, seed number per pod, and average number of seeds per pod.

This paper presents the results of research aimed at finding the possible ways of disposing of ceramic waste material, focusing mainly on the possibility of using it as aggregates in concretes exposed to an aggressive chemical environment (municipal sewage). The research part presents the preparation method and investigation of waste ceramic aggregates (red, glazed and sanitary ceramic aggregates). A suitable ratio of coarse to fine aggregates was selected, and their density, absorptivity and crushing strength were examined. All examined aggregates were also subjected to SEM analysis. Red ceramic aggregate is characterized by a greater degree of crushing compared to glazed and sanitary ceramic aggregate, by 205.7% and 439.4%, respectively. Another part of the research was to compare the properties of concrete with traditional aggregate (gravel, basalt) and with ceramic waste aggregate. The tested parameters included consistency, apparent density, absorptivity, flexural and compressive strengths of concretes. The study proved that the absorptivity of recycled composites is higher than that of traditional composites by 20.8–24.7%. The concrete based on sanitary ceramic waste has the highest strength parameters. Its compressive strength is higher by 10.5% and flexural strength by 5.9% compared with the basalt aggregate concrete. The compressive strength of sanitary ceramics concrete is higher by 42% and by 59% compared with concrete based on glazed ceramic and red ceramic aggregate, respectively. The last part of the research was to examine the resistance of concrete to aggressive environment. The scope of the work included the preparation of the research environment in the form of solutions with an increased concentration of aggressive agents (hydronium, sulfate, magnesium, ammonium ions). Among the concretes with ceramic aggregate, the highest decrease in the compressive strength was demonstrated by the concrete based on red ceramics (128.2%), while the smallest was demonstrated by the concrete based on sanitary ceramics (aggregate from sanitary ceramics (15.4%). The mass loss at different time intervals and compressive strength loss of samples stored in solutions were tested. The smallest weight loss caused by aggressive environment attack was recorded in the concrete based on ceramic sanitary and glazed aggregate (20.2% and 34.5%, respectively, after 120 days of aggressive environment).

Soybean has the ability to live in symbiosis with microorganisms and take up nitrogen from the atmosphere, fertiliser and soil reserves. The amount of nitrogen taken up from these sources depends on many biotic and abiotic factors, e.g., the rhizobium species, cultivar, as well as weather and agricultural conditions. A field experiment was conducted in eastern Poland (central Europe) in two successive growing seasons to examine the uptake of nitrogen from the atmosphere (NDFA—% nitrogen derived from the atmosphere), fertiliser (NDFF—% of nitrogen derived from fertiliser) and soil reserves (NDFS—% of nitrogen derived from the soil) for three non-GMO (non genetically modified organism) soybean cultivars: Abelina, SG Anser and Merlin. Pre-plant fertilisation of plants with nitrogen excess with the ¹⁵N isotope and the isotope dilution method were applied. Soil reserves and the atmosphere were major nitrogen sources for soybean. Soybean roots contained the most atmosphere-derived nitrogen (45.85%), the amount being lower for soil reserves (41.43%) and the lowest for fertiliser (12.72%). Harvest residues and seeds contained the most soil reserve-derived nitrogen, the amount being lower for the atmospheric nitrogen and the lowest for fertiliser-derived nitrogen. The amount of nitrogen derived from different sources in the whole soybean mass significantly depended on cultivars and years’ percentage values being affected by study years only. Less atmospheric nitrogen was accumulated in cv. Abelina roots (2.15 kg N·ha⁻¹) compared with cv. SG Anser (3.07 kg N·ha⁻¹) or cv. Merlin (2.89 kg N·ha⁻¹). More atmospheric nitrogen was recorded in the post-harvest residues and seeds of cv. Abelina and SG Anser than Merlin. The content of soil reserve-derived nitrogen taken up by the whole soybean plants averaged 61.29 kg N∙kg⁻¹, the amounts being 50.95 and 11.38 kgN∙kg⁻¹ for nitrogen taken up from the atmosphere and fertiliser, respectively. Soybean grown in the study year with more favourable thermal and precipitation conditions (2017) took up more nitrogen from all the sources compared with the year 2018.

Parameters of sexual activity were determined in 49 young boars used for artificial insemination, four times at three-month intervals. The parameters included the time from entering the arena until mounting the phantom; the time from mounting the phantom until achieving erection; the time from achieving full erection until the start of ejaculation; duration of ejaculation; and the number of times the boar mounted the phantom. Characteristics of the ejaculates were also assessed. The libido parameter associated with the greatest efficacy of artificial insemination was the effectiveness of artificial insemination service, the time from entering the arena until the start of ejaculation. The significance of this trait for predicting ejaculation performance was analysed. The libido characteristics were classified into three categories: boars with a short reaction time to the phantom, boars with an intermediate reaction time, and boars with a long reaction time. For these groups, the characteristics of ejaculates collected at the start of the period during which ejaculates were collected and after three, six and nine months were determined. The sexual experience of boars was not associated with the expression of sexual behaviour because young boars during their first three months of ejaculate collections required less time to initiate ejaculation. The ejaculates with the greatest utility were obtained after six months of service. These ejaculates had the largest volume (255.22 mL), and the most insemination doses could be prepared from these ejaculates. On average, more than 23 insemination doses were prepared from ejaculates collected after six months of semen collections, which is about four doses more than from ejaculates collected at the start of artificial insemination service (p < 0.01).The time from entering the arena to beginning ejaculation can be used to predict a boar’s future libido. A relationship was shown between the level of libido and ejaculate characteristics. The ejaculates of the boars which needed the longest time to begin ejaculation at the start of semen collections had the greatest sperm concentration and number. In group 3, the boars’ejaculates contained about 6–9 × 10⁹ more sperm than the ejaculates of boars from group 1. After six months of the experimental period, the difference was nearly 15 × 10⁹ sperm (p < 0.05), and after nine months, it exceeded 22 × 10⁹ sperm (p < 0.01).