Wiesław Bednarek

The effect of silicon on maize growth under cadmium stress

The effects of silicon (Si) supply (0, 0.1, 0.5, 1.5, 3.0, and 5.0 mM Si) on maize seedling growth, Si and Cd accumulation, and thiol peptide synthesis under Cd stress conditions were studied. The addition of Si to the growth medium resulted in the significantly higher Si accumulation in plant tissues. The average values of growth parameters (root and shoot fresh weights and root net elongation rates) showed a beneficial role of Si on growth of non-Cd-treated plants, while there was no evidence that silicon mitigated Cd toxicity in maize seedlings. Cadmium exposure depressed plant growth and induced phytochelatin (PC) synthesis. The accumulation of Cd and PCs in roots significantly decreased with increasing Si concentrations in the nutrient solution; however, their accumulation in shoots was not changed in the presence of Si.

Effect of cadmium on selected physiological and morphological parameters in metallicolous and non-metallicolous populations of Echium vulgare L.

Cadmium tolerance of three populations of Echium vulgare L., naturally occurring on two Zn-Pb waste deposits (metallicolous populations M1, M2) and on an uncontaminated site (non-metallicolous population, NM) was investigated. The plants were cultivated in hydroponics at 0, 5, 15, 30, or 50μM Cd for 14 days. Although Cd reduced the content of photosynthetic pigments indifferently in the three populations, plant growth parameters and root viability analyses confirmed different Cd tolerances decreasing in the order M1>M2>NM in the populations studied. Organic acids (tartrate, malate, citrate, succinate) were not responsible for the elevated Cd tolerance of the metallicolous populations, although malate and citrate might participate in Cd detoxification in the roots of the M1 and M2. Phytochelatin concentrations were higher in the roots of M1 and M2 populations of E. vulgare, suggesting their role in Cd detoxification and different Cd tolerances.

Selected secondary metabolites in Echium vulgare L. populations from nonmetalliferous and metalliferous areas

The aim of this study was to evaluate the effect of severe environmental conditions prevailing on metalliferous waste heaps and heavy metal-contaminated growth substrates on accumulation of selected secondary metabolites, antioxidant capacity, and heavy metal concentration in two metallicolous (MC, MZ) and one nonmetallicolous (NM) populations of Echium vulgare L. The shoots and the roots of the three studied populations were collected from their natural habitats. Additionally, the plants were cultivated on different growth substrates, i.e. a contaminated substrate obtained from the areas of growth of the MZ and MC populations and an uncontaminated one from the NM population site. Several compounds, i.e. allantoin, rutin, rosmarinic acid, chlorogenic acid, and 4-hydroxybenzoic acid were identified in the shoots. Moreover, rosmarinic acid, allantoin, and shikonin were measured in the roots. The adverse environmental conditions contributed to a ca. 10- and 4-fold increase in the concentration of allantoin in the roots and shoots, respectively, as well as a ca. 4-fold and ca. 3-fold increase in the level of 4-hydroxybenzoic acid and shikonin, respectively, in comparison with the plants from the uncontaminated site. Similarly, a great impact of the contaminated substrate on the compounds was demonstrated in the soil experiment. Regardless of the populations, even ca. 20-fold higher levels of allantoin and shikonin were observed in plants grown on the MC and MZ substrates. In contrast, the chlorogenic acid concentration was lower in plants collected from the metalliferous areas and in all populations cultivated on the contaminated substrates in comparison with plants from the uncontaminated soil. Unambiguous results were obtained in the case of rutin, i.e. decreased accumulation in both metallicolous populations from the natural environment and increased accumulation in plants grown on the contaminated substrates. The high concentrations of heavy metals in the substrates contributed to high HM concentrations in plant tissues. However, some differences were observed between the metallicolous and nonmetallicolous populations - the accumulation of metals was lower in the shoots and higher in the roots of the NM population, compared with the MZ and MC populations.

NITRATE NITROGEN IN THE SOILS OF EASTERN POLAND AS INFLUENCED BY TYPE OF CROP, NITROGEN FERTILISATION AND VARIOUS ORGANIC FERTILISERS

This paper describes the influence of nitrogen and organic fertilisation and the type of crops on the contents of NO3-N in arable land. The large-scale environmental research was carried out in 2004-2006. Soil samples were taken from 411 places throughout the Lublin region in two seasons: spring and autumn. The concentration of nitrate(V) depended on fertilisation and crops. It was found that application of N-fertiliser above 121 kg N ha-1 caused a significant increase in the nitrate(V) concentration in the surface soil layer. The distribution of NO3-N in the soil profile indicated a possibility of nitrate(V) leaching during winter and early spring. On fields treated with a liquid organic fertilizer, the content of NO3-N was considerably higher than on the other fields. The lowest NO3-N was observed in straw treatments. A higher content of NO3-N was noted in sugar beet and vegetable objects, while fallow, rye or rough grazing decreased accumulation of nitrate(V) in the soil profile.

Effects of Soil Properties and Nitrogen Fertilization on Distribution of NO3-N in Soils of Eastern Poland

The effects of anthropogenic (nitrogen fertilization) and natural [soil texture, pH content of humus, ammonium nitrogen (N-NH4), and the available forms of phosphorus (P), potassium (K), magnesium (Mg)] factors on nitrate nitrogen (NO3-N) content and distribution were shown. The dependencies between these factors and the content of NO3-N in soil were estimated in three soil layers: 0–30 cm; 31–60 cm; 61–90 cm. The research was carried out in 2004–2006, and the soil samples were taken from 411 places throughout eastern Poland in two seasons: spring and autumn. The concentration of NO3-N significantly depended on the year of investigation, season of the year, and depth of sampling. Distribution of NO3-N in the soil profile indicates possibility of NO3 leaching during winter and early spring. The results also provide evidence that application of more than the optimum N rate considerably increases NO3-N, especially in soil with low humus content.

Relationship between assimilable-nutrient content and physicochemical properties of topsoil

Abstract In the years 2008-2011, an environmental study was conducted for Polish soils, focusing on the south-eastern Poland soils, as they exhibit significant acidification. This study aimed at assessing the current pHKCl and the supply of basic macro- (P, K, Mg and S-SO4) and microelements (B, Cu, Fe, Mn and Zn) in the collected soil samples, and also at determining their relationship with the soil agronomic category, humus content and pH class. Soil reaction and humus and macronutrient content were positively correlated with the amount of colloidal clay and particles < 0.02 mm. In the majority of cases, the macro-element content in the soil was positively correlated with soil pH and humus content. As for microelements, a usually significant and positive correlation was found between the soil agronomic category and the content of manganese, iron and zinc, whereas for the content of boron and copper, no such relationship was observed. A significant and positive correlation between soil reaction and the content of manganese, iron and boron was also found. Such correlations were not observed in relation to copper and zinc content. Statistical analysis indicated that the content of boron and manganese depended to the greatest extent on the investigated physicochemical properties.

Estimation of the macro- and micronutrient status of raspberries grown in the Lublin region

Abstract Environmental monitoring was conducted in the Lublin region in 2009-2012 aimed at the assessment of the supply of several macro- and micronutrients in raspberries plants. The plantations studied were located in eight main regions for the growing of raspberries (Bełżyce, Chodel, Godziszów, Kraśnik, Lublin, Międzyrzec Podlaski, Opole Lubelskie and Urzędów). The contents of nitrogen (N), potassium (K), phosphorus (P), magnesium (Mg), calcium (Ca), iron (Fe), manganese (Mn), zinc (Zn), copper (Cu) and boron (B) were determined in raspberry leaves. Furthermore, the impact of select soil properties on the content of essential elements in the leaves was assessed. The results obtained revealed the suitable N, P, K, Mg, B, Zn and Cu supplies in the plants. However, the mean content of Mn greatly exceeded the optimal level recommended for this species. Also, the content of Fe in some regions was above the optimal value. The calculated correlation coefficients between soil properties and the content of the elements in raspberry leaves suggest that these variables were interdependent in only a few cases.

ESTIMATION OF THE STATUS OF SUPPLY OF TOMATOES GROWN IN THE LUBLIN REGION IN CERTAIN MACRO- AND MICROELEMENTS

In the years 2009–2011, in the Lublin Region, an environmental study was conducted with the objective of estimation of the supply of tomato plants with macroand microelements. The estimation was conducted after performing chemical analyses of leaves of those plants. Inzynieria Ekologiczna vol. 38, 2014, 35–41 DOI: 10.12912/2081139X.31