Effect of neutralising substances on the total content of trace elements in soil contaminated with zinc

Trace elements are particularly important not only for plants but also for soil organisms. However, excessive concentrations of trace elements can be toxic to organisms, in which they can cause various disorders. Application of mineral and organic substances increases the soil sorption capacity and reduces the uptake of heavy metals by plants. A study was undertaken to determine the content of trace elements in zinc-polluted soil after an application of some neutralising substances. Soil was polluted with zinc in doses of 0, 150, 300 and 600 mg kg-1 of soil. To reduce the negative impact of zinc, the substrate was amended with compost (3%), bentonite (2%) and zeolite (2% relative to the soil mass). Soil pollution with Zn and application of neutralising substances significantly affected the soil content of trace elements. In the series without neutralising substances, the increasing soil pollution with Zn caused an increase in the content of this metal and Pb, but a decrease in the content of Ni, Cu and Cd, compared with the control treatment (without Zn). Bentonite and compost reduced the content of Zn and Pb, particularly in the treatments most severely polluted with Zn. All the tested substances caused a decrease in the soil content of Ni, Cu and Co compared with the series without neutralising substances. Zeolite had the strongest effect on the content of Cu and Co, whereas compost affected most strongly the content of Ni in soil. Application of bentonite and zeolite contributed to an increase in the soil content of Cr and Fe, but the effect of bentonite was significantly stronger than that of zeolite. Moreover, zeolite resulted in a small significant rise in the soil content of Pb compared with the control

Adherence of Candida sp. to host tissues and cells as one of its pathogenicity features

The ability of Candida sp. cells to adhere to the mucosal surfaces of various host organs as well as synthetic materials is an important pathogenicity feature of those fungi which contributes to the development of infection. This property varies depending on the species of the fungus and is the greatest for C. albicans. The process of adhesion depends on plenty of factors related to the fungal and host cells as well as environmental conditions. The main adhesins present on the fungal cell wall are: Als, Epa, Hwp1, but also Eap1, Sun41, Csh1 and probably Hyr1; for adhesion significant are also secreted aspartyl proteases Sap. Various researchers specify a range of genes which contribute to adhesion, such as: CZF1, EFG1, TUP1, TPK1, TPK2, HGC1, RAS1, RIM101, VPS11, ECM1, CKA2, BCR1, BUD2, RSR1, IRS4, CHS2, SCS7, UBI4, UME6, TEC1 and GAT2. Influence for adherence have also heat shock proteins Hsp70, Mediator Middle domain subunit Med31 and morphological transition. Among factors affecting adhesion related to host cells it is necessary to mention fibronectins and integrins (receptors for Candida sp. adhesins), type of epithelial cells, their morphology and differentiation phase. To a lesser degree influence on adhesion have nonspecific factors and environmental conditions

Effect of neutralizing substances on zinc-contaminated soil on the yield and macronutrient content in yellow lupine (Lupinus luteus L.)

Some trace elements, for example zinc, play both a positive and a negative role in plant life, which requires their content in soil. If soil is excessively contaminated with zinc, an attempt should be made to reduce the negative effect of this element on plants and other living organisms. For this reason, a study was undertaken to determine whether it was possible to alleviate the effect of soil zinc contamination (0, 150, 300 and 600 mg Zn kg-1 of soil) on the yield and macronutrient content of yellow lupine (Lupinus luteus L.). Compost (3%), bentonite (2%) and zeolite (2% relative to soil mass) were used to reduce the effect of soil zinc contamination. Macro- and micronutrients were applied to the soil in the same amounts in all pots: 30 mg N, 30 mg P, 100 mg K, 50 mg Mg, 0.33 mg B, 5 mg Mn and 5 mg Mo per kg soil. Yellow lupine was harvested in the flowering phase and plant material samples were collected for laboratory tests. The induced soil zinc contamination reduced yellow lupine growth and development because a dose of 300 mg Zn kg-1 soil caused plant seedlings to wither. Compost and bentonite reduced the negative influence of soil zinc contamination on yellow lupine yield, especially on aerial parts. The most demonstrable effect of zinc on the macronutrient content of lupine plants was recorded for magnesium and calcium, whose content increased compared to the control in both the aerial parts and roots of yellow lupine. Among the neutralizing substances, the effect of zeolite on the phosphorus, magnesium and calcium content and bentonite on the sodium content in the plants was the most beneficial

Content of some nutrients in Scots pine, silver birch and Norway maple in an urbanized environment

In the late 18th and early 19th c., a drastic reduction in the area of forests due to their excessive exploitation occurred in Europe, which gave rise to the birth of afforestation efforts. The chemical composition of plants, including trees, depends on the many biotic and abiotic environmental factors. The aim of this study was to determine the content of some nutrients in needles and bark of Scots pine (Pinus sylvestris L.), leaves and bark of silver birch (Betula pendula) and Norway maple (Acer platanoides L.), depending on their location. The content of phosphorus, potassium, sodium, calcium and magnesium depended on a plant species, plant organ and the location of sample collection. The leaves of silver birch, compared to its bark, contained ten-fold more potassium and six-fold more phosphorus and magnesium. The content of phosphorus was the highest in silver birch leaves in the center of Olsztyn. The highest potassium content was observed in silver birch leaves and Norway maple bark in the center of Olsztyn. The calcium content was the highest in the leaves and bark of maple trees growing near State Road 51 and in the leaves of this species in the city center. The highest sodium content was detected in the leaves and bark of most tree species growing along State Road 51 and in the center of Olsztyn