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Przeprowadzono analizę zawartości wybranych makroelementów i mikroelementów w twarogu kwasowym o różnej zawartości tłuszczu. Materiał badawczy stanowił twaróg kwasowy chudy (0% tłuszczu), półtłusty (4% tłuszczu) i tłusty (8% tłuszczu), pochodzący od jednego producenta. W badanym twarogu oznaczono zwartość suchej masy oraz popiołu całkowitego. Próbki twarogu poddano mineralizacji na mokro, a następnie oznaczano w nich zawartość wybranych makroelementów (P, Ca, Mg, K, Na) i mikroelementów (Zn, Fe, Cu, Mn). Zawartość Ca, Mg, Zn, Fe, Cu i Mn oznaczono techniką płomieniowej spektrometrii absorpcji atomowej (płomień acetylen – powietrze). K i Na oznaczano techniką emisyjną (płomień acetylen – powietrze). Do oznaczenia zawartości P zastosowano metodę kolorymetryczną. Badany twaróg kwasowy chudy, półtłusty i tłusty różnił się istotnie pod względem zawartości suchej masy. Twaróg kwasowy chudy charakteryzował się istotnie większą zawartością popiołu całkowitego niż twaróg kwasowy półtłusty i tłusty. W przeprowadzonych badaniach wykazano istotne różnice między badanym twarogiem kwasowym w zawartości P, Ca, K, Na, Zn, Fe, Cu i Mn, nie wykazano natomiast istotnych różnic w przypadku zawartości Mg. Bez względu na zawartość tłuszczu w badanym twarogu kwasowym w największych ilościach spośród oznaczonych makroelementów (około lub powyżej 100 mg · 100 g–1 produktu) występował: fosfor, potas i wapń, natomiast spośród mikroelementów (w ilości powyżej 600 μg · 100 g–1 produktu) – cynk.
This study presents the results of studies on the chemical composition of rhizomes of Nuphar lutea which were carried out from July 2006 to November 2007 (the samples were collected at two-week intervals from March to November 2007). The first indication of the start of the growing season was the growth of leaves in the apical part of the rhizomes. Clearly visible signs that marked the beginning of the growing season were unfolding of leaves, which became arrow-shaped. The leaves had already unfolded and were arrow-shaped (saggitate) on April 10th when the temperature of the bottom water layer was 7oC. It may be assumed, therefore, that the growing season began between the 28th March and 10th April 2007. The phosphates, nitrates, sodium, calcium, total iron and sulphates levels in the rhizomes declined just after the growing season had started. The total nitrogen content remained at a constant level whereas the amount of dissolved silica increased. Considerable changes in the macroelement contents were noted when Nuphar lutea was in full bloom (10th-24th June). The macroelement contents presented in the tables and diagrams were expressed on a dry matter basis. An additional table illustrates the macroelement contents expressed on a fresh matter basis. The problem of collecting rhizomes of polycormic plants is discussed.
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A large area trial involving four methods of soil fallowing (goat’s rue, traditional fallow, goat’s rue + brome grass, brome grass) was established in the spring 1996. This paper contains the results of our investigations concerning the content of macroelements in plants in the years 2000-2004. The weakest accumulation of nitrogen, potassium and magnesium by mono- and dicotyledonous plants occurred in the traditional fallow field; slightly richer concentration of the macroelements was determined in plants growing on the object sown with brome grass. Goat’s rue, both in a monoculture and mixed with brome grass, stimulated plants to accumulate more nitrogen, phosphorus, potassium and magnesium. Using goat’s rue to raise the content of macroelements in plants can prevent transfer of those elements to lower soil layers.
The processes of growth and development as well as the yield quality of crops depend on the abundance of soil nutrients and the ability of the plants to uptake nutrients. Nutrients can be taken up more efficiently after application of a biostimulant. The effect of biostimulants depends on the content of their active substance as well as the dose, timing and frequency of their application. In 2009-2011, a controlled field experiment was conducted in the Kuyavian-Pomeranian Province (53°13′N; 17°51′E). The objective was to analyse the effect of the timing and doses of foliar application of the biostimulants: Kelpak SL (seaweed extract containing phytohormones) and Asahi SL (a mixture of phenolic compounds) on the content of macroelements: Mg, P, Ca, N, Na and K in the storage roots of carrot directly after harvest and after storage (for 6 months in chambers with controlled conditions: temp. +1°C, Rh 95%). Kelpak SL was applied once in a dose of 3 or 2 dm3 ha-1, twice in doses of 3+2 dm3 ha-1 or 2+2 dm3 ha-1 at intervals of two or four weeks, as well as three times in doses 3+2+2 dm3 ha-1 or 2+2+2 dm3 ha-1, every two weeks. Asahi SL was applied twice in doses 0.5+0.5 dm3 ha-1,at a two-week interval. The first application of biostimulants was always performed at the 4-leaf stage. The study showed that the biostimulants Kelpak SL and Asahi SL, irrespective of the dose and frequency of application, increased the N concentration in the carrot roots. An increase in the Mg, P, Na and K concentrations was observed after a single application of Kelpak SL in a dose of 2 dm3 ha-1, and in the Ca concentration after a dose of 3 dm3 ha-1. Asahi SL did not affect the Mg, P, Ca and Na concentrations but increased the K content in the roots. After storage, the content of Mg, Na and K decreased, whereas the concentration of P, Ca and N did not change. Directly after harvest and after storage, positive correlation between N and K and between N and Na, as well as between Na and K was indicated.
This study presents the results of monitoring studies carried out to determine the chemical composition of Nuphar lutea in two phytocoenoses of Nupharo-Nymphaeetum albae Tomasz. 1977 occurring in two lakes of different trophic types (eutrophic Lake Łaśmiady and oligo-humotrophic Lake Pływające Wyspy). The leaves (collected starting in May), rhizomes and roots of Nuphar lutea as well as water and sediment samples were collected from March to November in the above phytocoenoses (for 3 years in Lake Pływające Wyspy and for 4 years in Lake Łaśmiady). The samples were analysed for several parameters including: phosphate, nitrate, total nitrogen, potassium, sodium, calcium, total iron, sulphate and silica dissolved. In addition the manganese, cadmium, zinc and lead contents were determined in the leaves, rhizomes and roots of the plants collected in July (at the height of the growing season). It was found that the differences in the chemical composition of water and sediments between the lakes studied were more pronounced than in the case of leaves, rhizomes and roots of Nuphar lutea.
Eggplant fruits are abundant in potassium, the amount of which ranges from 200 to 600 mg K⋅100 g-1 FM, depending on a variety. They are also a rich source of phosphorus, magnesium, calcium, and iron. As there are no fertilization recommendations for eggplant cultivation under cover, this study been undertaken to evaluate the vegetable’s requirements. The aim was to test how the type and dose of potassium fertilizer influences nitrogen, phosphorus, calcium, and magnesium levels in eggplant fruits. The experiment on cv. Epic F1 eggplant was carried out in unheated polyethylene tunnel in 2004-2005. The eggplant was cultivated on peat subsoil in 10 dm3 capacity cylinders made of rigid plastic. The experiment was set up in a two-factor, completely randomized design. The influence of two factors was examined: I – type of potassium fertilizer (KCl, K2SO4, KNO3), and II – potassium rate (8, 16, 24 g K⋅plant-1). Fruit samples for laboratory determinations were collected in mid-August, in the middle of fruiting stage. Fruits were harvested at the stage of technological maturity and the following were determined: Ntot, P, K, Ca, Mg. The results were processed by variance analysis. Significantly higher total nitrogen and potassium concentrations in fruits of plants fertilized with potassium nitrate as compared to the other two fertilizer types were recorded. Increasing potassium doses, regardless the fertilizer type, considerably increased the element content in eggplant fruits and widened the K:Ca ratio value. The diversification of potassium fertilization did not have significant influence on phosphorus and magnesium concentrations in eggplant fruits. No significant changes in calcium content in fruits were observed when applying potassium sulfate or nitrate, while higher potassium chloride rates significantly decreased the concentration of this element in fruits.
The study was carried out in 2002 and 2003. The experimental material was basil plants cultivated in the field for a bunch harvest, using for plant covering perforated foil and polypropylene unwoven cloth. The control object was basil grown without covering. The covers tested in the experiment had a significant influence on the yielding of basil cultivated for a bunch harvest. The highest yield was obtained when polypropylene unwoven cloth was used. Basil plants grown under polypropylene unwoven cloth were the highest (18.2 cm), had the biggest diameter (13.4 cm) and the largest leaves (5.9 cm long and 3.3 cm wide). Using covers (perforated foil and polypropylene unwoven cloth) caused a decrease of dry matter content in the yield of basil, in comparison with the plants grown without covering.The covers used in the study caused a decrease of nitrogen, potassium, calcium and magnesium in the basil yield, but did not decrease phosphorus and sodium content.
Lead has been used extensively for thousands of years. Once introduced into the environment, like any other heavy metal, lead accumulates in soil and sediments. High lead concentrations in river and lake sediments can be harmful to aquatic organisms. At present, uncontaminated water sediments in the northern and central parts of Poland contain below 9 mg of lead per kg. The lakes located within the following lake districts: Greater Poland, Pomeranian and Masurian, provided 409 samples of surface sediments from deep spots (the profundal zone). All the samples were tested for the content of Pb and other selected macroelements. The content of Ca, Mg, Fe, K, Mn, Na, P, Pb and S was determined by ICP-OES and the total organic carbon (TOC) was evaluated by the coulometric titration method. The observed range of lead concentration was from below 3 to 222 mg kg-1. The average content was 37 mg kg-1, the geometric mean 30 mg kg-1, and the median 33 mg kg-1. In the majority of samples, the lead concentration was higher than the geochemical background. Only in 5.77% of the samples, the lead content was lower than 10 mg kg-1. The lead concentration in the sediments was relatively well correlated with the total organic carbon (r = 0.59), aluminium (r = 0.45) and sulphur (r = 0.47), moderately correlated with iron (r = 0.26) and potassium (r = 0.28), very weakly correlated with phosphorus (r = 0.12) and negatively correlated with the calcium concentration (r = -0.28). No correlation was observed for manganese (r = -0.05), magnesium (r = 0.07) and sodium (r = -0.07). Factor analysis revealed the presence of two factors that together accounted for nearly 45% of variation. The first factor included aluminium, potassium and magnesium, and the second one - sulphur and organic carbon. The lead share was low in the first factor (0.343), but very high in the second factor (0.757). Based on the results of the factor analysis, it can be assumed that lead in the organic matter-rich sediments of the profundal zone is deposited mainly in the form of sulphides. Lead concentration varied among the sediments obtained from various lake districts; it was lower in the lakes located within the Pomeranian Lake District than in those from Greater Poland and Masurian Lakes.
The aim of this study was to comparison of chemical components and antioxidant activity in leaves of winter and spring varieties of garlic, obtained from POLAN Company; Krakow, Poland) as well as in leaves of wild (bear’s) garlic. The content of basic chemical components were determined according to the AOAC methods. Selected minerals content was determined according to the PN procedure. Vitamin C and polyphenols were determined using the Tillman’s and Folin-Ciocalteau’s methods, respectively. The ability to scavenging of the ABTS•+ was analyzed by Re et al. method. Leaves of wild garlic had the significantly lowest amount of dry matter (79.0 g·kg⁻¹), proteins (13.7 g·kg⁻¹), total carbohydrates (50.8 g·kg⁻¹), dietary fiber (26.9 g·kg⁻¹), ash (8.9 g·kg⁻¹), vitamin C (956.1 mg·kg⁻¹), and antioxidant activity (25.0 mmol TEAC·kg⁻¹), but the highest level of crude fat (5.6 g·kg⁻¹), potassium (34.6 g·kg⁻¹), magnesium (1.72 g·kg⁻¹), iron (230.3 mg·kg⁻¹) and zinc (58.8 mg·kg⁻¹) as compared to winter and spring varieties. At the same time, there was no unambiguous differences in the level of basic chemical components (proteins 20.9 ÷ 35.7 g·kg⁻¹, fat 1.6 ÷ 2.8 g·kg⁻¹, total carbohydrates 61.3 ÷ 116.5 g·kg⁻¹, fibre 33.7 ÷ 57.0 g·kg⁻¹, ash 8.9 ÷ 14.1 g·kg⁻¹), antioxidants (vitamin C 75.4 ÷ 459.7 mg·kg⁻¹, polyphenols 335.3 ÷ 1895.1 mg·kg⁻¹), antioxidant activity (27.0 ÷ 30.1 mmol TEAC·kg⁻¹) and the amount of minerals (calcium 7.55 ÷ 28.9 g·kg⁻¹, potassium 15.9 ÷ 28.0 g·kg⁻¹, magnesium 0.85 ÷ 1.32 g·kg⁻¹, sulphur 2.41 ÷ 6.22 g·kg⁻¹, iron 34.4 ÷ 85.7 mg·kg⁻¹, zinc 9.32 ÷ 13.8 mg·kg⁻¹) between winter and spring varieties, as well as between winter varieties.
The purpose of this work was to determine the impact of weather conditions during the spring and summer growth of winter triticale on the yield and content of nutrients in its grain. The research results were achieved from a controlled field experiment carried out at the Experimental Station of the University of Warmia and Mazury in Olsztyn, located in Tomaszkowo near Olsztyn (53o42’ N; 20o26’ E). The impact of weather factors during the spring and summer growth of winter triticale on the yield and content of nutrients in its grain was explained by correlation and multiple regression analyses. The duration of the spring and summer growing season (b ́= 0.929**) and the average daily temperatures during the plant growth (b ́= 0.409*) had the strongest, significantly positive impact on winter triticale yield. A significant linear correlation was found only between the content of nitrogen and potassium in winter triticale grain and the selected weather parameters. The nitrogen content depended on the number of plant growing days and average minimum daily temperature, while the potassium content was affected by the number of spring and summer growing days, average daily temperature, total precipitation volume and the number of days with precipitation. Considering the cumulative impact of the examined weather parameters on the content of macroelements in triticale grain, a significant effect was found for phosphorus and potassium, whose levels depended, to the largest extent, on the precipitation volume and number of days without precipitation ≥10 days, respectively. The content of phosphorus and nitrogen in grain was significantly negatively correlated with the yields of winter triticale.
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