Maciej Bosiacki

The primary goal of this study was to assess how two techniques for applying progressively higher doses of zinc and cadmium impact seed germination of selected ornamental plant species. The experiments were conducted in the accredited laboratory of the W. Legutko Breeding and Seed Company in Jutrosin, along with the Department of Plant Physiology at Poznań University of Life Sciences. Seeds from two ornamental species, Eschscholzia californica Cham. and Coreopsis lanceolata, were utilized. Two methods were used to treat the seeds with heavy metal solutions, involving four distinct two-factor experiments, each comprising eight combinations. This methodology adhered to the current ISTA guidelines. Germination energy was assessed after 7 days, while germination capacity was measured after 14 days. The two methods exhibited different effects on germination capacity and energy. The technique for treating seeds with heavy metal solutions and the duration of exposure to the metals play a significant role in germination. Soaking Eschscholzia californica Cham. seeds in increasing doses of zinc and cadmium solutions for 10 min before sowing showed no significant effect on their energy or germination capacity. Likewise, soaking Coreopsis lanceolata seeds in zinc solutions for 10 min before sowing did not significantly influence their energy and germination capacity. However, soaking Coreopsis lanceolata seeds in cadmium solutions for 10 min before sowing did not notably affect their germination capacity but significantly diminished their germination energy. Extended exposure of seeds placed on blotting paper soaked in cadmium sulfate and zinc sulfate solutions across all concentrations reduced energy and germination capacity for Eschscholzia californica Cham. and Coreopsis lanceolata seeds.

Understanding soil properties that govern physicochemical and biological processes is essential for achieving high crop quality and yield. Organic matter is an important element of soil fertility and fertility in vegetable cultivation. In the process of decomposition of organic matter in the soil, humus of various quality is formed. The quality of humus depends on the content of individual acids (fulvic, humic and hymatomalanic acids) in it, which can affect the binding–chelation of heavy metals, limiting their availability to plants. The conducted studies determined the effect of adding organic matter (high peat, brown coal and wheat straw) to mineral soil on nickel detoxification in radish, its yield, nitrogen management and chloroplast pigments. The studies were conducted for three years in a greenhouse in a container system. The tested substrates were contaminated with nickel in the amount of 50, 75 and 100 mg dm⁻³. It was found that introducing organic matter into mineral soil can affect the reduction as well as the increase in nickel content in edible parts of radish. The type of organic material introduced into mineral soil as a source of organic matter has a significant impact on nickel content in radish. It was shown that nitrate reductase activity (NR) depends to a large extent on the substrate in which the plants are grown as well as on the applied dose of nickel. A similar relationship was demonstrated in the case of changes in the level of chloroplast pigments (chlorophyll a, chlorophyll b and carotenoids).

Studies were carried out in order to verify the research hypothesis that “the introduction of organic matter in the form of high peat, brown coal, and wheat straw to the mineral soil contaminated with nickel will reduce the content of this metal in the lettuce”, the main purpose of which was to determine the impact of various organic materials with varying degrees of decomposition on the content of nickel in lettuce leaves. The factors of the experiment were different types of organic material that were added to the mineral soil (loamy sand), such as high peat, brown coal, and wheat straw. The substrates in which lettuce was grown were contaminated with increasing doses of nickel: 0, 50, 75, and 100 mg Ni·dm⁻³ of the substrate. This research shows that the type of organic material introduced into the mineral soil as a source of soil organic meter has a significant impact on the content of nickel in lettuce leaves.

Four taxa of Spiraea were selected for this study: S. × cinerea Zabel ‘Grefsheim’, S. nipponica Maxim. ‘Snowmound’, S. splendens É. N. Baumann ex K. Koch and S. × vanhouttei (Briot) Carrière growing for a minimum of 5 years along heavily trafficked traffic routes. This study included the genus Spiraea due to its popularity in horticultural practice (commercial availability, widespread in urban environments). In addition, the use of ornamental shrubs for phytoremediation in urban green spaces effectively combines the aesthetic needs of residents with those of caring for the urban environment. This study was conducted in Poznań (population 550,000, the fifth largest city in Poland). Soils and foliage were examined in spring and autumn. Soil pH and specific electrolytic conductivity (EC) were determined. The content of micronutrients (Cu, Fe, Mn, Ni, Zn) and toxic heavy metals (Cd, Cr, Pb) in soil dry matter and leaves was determined. The uptake capacity of bioavailable forms of heavy metals by Spiraea from the soil was analyzed by determining the bioconcentration factor (BCF). It was found that the studied taxa meet the basic requirements for plants used for soil phytoremediation processes, especially for chromium phytoextraction. The degree of salinity of the tested soils did not pose a threat to the shrubs growing there, and most of the sites, despite the alkaline reaction, are suitable for their cultivation. S. × cinerea and S. × vanhouttei have BCFs for lead <1. The remaining taxa are characterized by strong concentrations of all analyzed elements. A particularly high BCF, above 10, was recorded for chromium and high for manganese and nickel.

An experiment was conducted to compare the effect of applying half a dose of a mineral fertiliser combined with a foliar treatment with four biostimulants and two fertilisers in relation to a full dose of a mineral fertiliser. The M.9 rootstock stoolings were sprayed four times during their growth. Each year of the experiment, the height, the diameter, the fresh weight of leaves and the leaf surface area of all stoolings were measured. The efficiency of rootstocks from one mother plant was assessed. Some parameters of physiological processes as well as the content of micro- and macronutrients in the leaves were also assessed. The research results showed that the reduced dose of the mineral fertiliser with foliar treatment did not significantly decrease the growth parameters of the M.9 rootstock stoolings. Some foliar treatments, especially Bioamino Plant and Bispeed, resulted in higher fresh weight and larger leaf area of the stoolings. The treatment with the Bioamino Plant biostimulant and two foliar fertilisers resulted in parameters of the physiological processes of stoolings that were the same as or better than those in the control plants. After the foliar application of two fertilisers, the content of macronutrients in the leaves of the stoolings was usually the same as in the control. The treatment with the biostimulants resulted in a lower content of most macronutrients in the plants (N, K and Ca). The only exception was the higher magnesium content than in the control after the treatment with all biostimulants and the same phosphorus content after the treatment with most of the biostimulants. The Aminoplant and Bispeed biostimulants increased the accumulation of iron in the leaves, whereas the Basfoliar 6-12-6 fertiliser resulted in higher zinc and copper content than in the control plants.

The influence of selected fertilizer within a 6-month period of operation was assessed: Basacote Plus ^6M, Osmocote Plus ^6M, Plantacote Plus ^6M. Plants grown in the substrate without slow-release fertilizer, which were supplied with nutrients only for top dressing, were the control. Two cultivars of the Maxi type of cyclamen were grown in greenhouse in pots during the period from the 25th to the 50th week of the year. While planting the seedlings, 2 g of slow-release fertilizer were added to the substrate directly under the roots. From the third week of cultivation, the plants of each combination were fertilized with top dressing every week. Plant height and diameter, number of leaves, weight of the above-ground part, tuber diameter, earliness of flowering, number of flowers and buds, as well as the content of macro and micronutrients were assessed. The addition of Osmocote ^6M or Plantacote ^6M into the substrate resulted in plants with a larger fresh weight and larger diameter and earlier flowering with more flowers and buds at the end of the experiment than with Basacote ^6M or with only top dressing. The applied slow-release fertilizers had an effect on the content of K, Ca, and Fe in the leaves of Persian cyclamen. The cultivar ‘Rainier White F1’ had significantly more leaves, buds, and flowers and a higher content of P, K, Cu, Zn, and Mn than the cultivar ‘Halios Pure White Compact F1’.

The aim of the study was to analyse the quality of soil in urban allotment gardens in the context of the production of home-grown vegetables. The study was conducted on six allotment gardens (31 individual plots) in Gorzów Wielkopolski, a medium-sized Polish city with an average level of industrialisation. The following soil characteristics were analysed: pH, electric conductivity, organic matter, organic carbon, humus, total nitrogen, C:N ratio, NH₄⁺-N, NO₃-N⁻, P, K, Ca, Mg, SO₄⁻-S, Cl, Na, Fe, Cu, Zn, Mn, Ni, Cr, Cd, Pb. The analyses showed that the soils were abundant in necessary nutrients for vegetable growing. They had high content of calcium, magnesium, and phosphorus. However, the soil pH in areas of vegetable cropping was too high. The content of toxic heavy metals—cadmium (0.22–0.59 mg∙kg⁻¹ d.m.) and lead (3.46–16.89 mg∙kg⁻¹ d.m.)—was within the acceptable limits. Nevertheless, the chemical analysis of carrots used as test vegetables showed that the permissible limits of cadmium and lead content in their roots were exceeded. The excessive uptake of these toxic metals can be reduced by lowering the soil pH and applying organic carbon to the soil.

Cultivation of sweet cherry trees is growing in popularity in Poland thus there is an increasing demand for good quality nursery material. The growth of maiden sweet cherry trees of ‘Vanda’ depending on three rootstocks was compared within three years of the nursery experiment. Also the nutritional status as well as photosynthetic activity of maiden trees after the use of four foliar preparations were in the scope of interest. On the basis of the size of the trunk diameter and weight of maiden sweet cherry tree fresh mass as well as on the basis of dry mass of leaves, the strongest vigor of growth was observed on Colt rootstock, contrary to the vigor on GiSeLa 5 rootstock, in which it was the weakest. Maidens produced on Colt rootstock formed more lateral shoots in comparison to other rootstocks. After foliar fertilization, maiden sweet cherry trees growing on Colt rootstock did not show better parameters of growth, except for Maxi Grow Excel preparation that caused better results of growth. The influence of preparations used on the content of macro and microelements was differentiated. A positive effect of all preparations was noted as far as gas exchange parameters were concerned, especially in the case of Maxi Grow Excel.

PAHs belong to persistent organic pollutants (POPs) found in the natural environment. They eventually accumulate in the highest quantities in soil. The purpose of this study has been to determine quantities of PAHs in soil depending on the method applied to control weeds in rows of a 4-year plantation of hazel (mulch fabric, bark chips, sawdust, manure compost, bare fallow, chemical fallow, grass sward). The highest concentration of PAHs (16 PAHs) was found in soil kept as bare fallow. The second most abundant concentration of these compounds was determined in soil under grass sward, followed by soil under sawdust, chemical fallow, and fabric. Less of these compounds accumulated in soil mulched with bark chips. The best method for protection of orchard soil against the accumulation of unwanted and toxic PAHs was mulching with manure compost. In most cases, lower concentrations of PAHs (total 16) were found in the subsoil (30–60 cm) than in the topmost soil layer, except the soil covered with mulch fabric, where fourfold more PAHs accumulated.