Barbara Filipek-Mazur

Legumes play an important role in agriculture by enriching soil with nitrogen, drawing water and nutrients from deeper soil layers, and supplying organic matter. They are also a valuable source of food for humans and animals. Protecting these plants from pests usually involves the use of synthetic products, whilst non-chemical methods remain poorly understood. The use of plant-based extracts is one possible approach. There is limited data in the available literature on the use of aqueous extracts (which is an easy and potentially low-cost solution) to protect legumes from pests. In particular, there is a lack of long-term studies conducted under field conditions. Accordingly, the aim of the three-year field studies was to determine the effect of aqueous tarragon extracts, prepared from dried and fresh plant material at concentrations conventionally defined as 2% (D2), 5% (D5) and 10% (D10) for the dried material, and 10% (F10), 20% (F20) and 30% (F30) for fresh material, on the control of two serious legume pests: Sitona spp. weevils and the broad bean weevil (Bruchus rufimanus Boh.). Aqueous extracts of tarragon reduced the area of losses and the percentage of leaf blade losses caused by adult Sitona spp. There were no significant differences between extracts using dry or fresh material as well as between different concentrations of the extracts. The effect of extracts was visible particularly during the early stages of plant growth in two out of three study seasons; this is especially significant given that these insects cause the worst damage during this period. No significant effect of the most studied extracts on the feeding of Sitona spp. larvae was observed. In D10 and F10 there was a significantly lower proportion of damaged nodules than in the control; however, this effect was markedly weaker than when Ch was used. All extracts from the dried plant material and F30 proved to be effective in reducing seed damage caused by B. rufimanus. However, the percentage of damaged seeds remained high, indicating that weekly application of tarragon extracts is not sufficient to protect broad beans against this pest. Taking into account the effect on the plants’ morphological parameters, the aqueous extract prepared from dried material at a concentration of 10% (D10) should be considered the most effective in practice. The damage caused by adult Sitona spp. and B. rufimanus differed significantly between years of the study.

The optimization of crop production in the context of agricultural land use and production inputs is a strategic element of sustainable development. Fertilization and irrigation are vital components of agricultural engineering, driving crop quantity and quality. The objective of the study discussed here was to assess greenhouse gas emissions from carrot cultivation depending on the variant of the fertilization and irrigation processes. One tonne of marketable carrot yield was selected as the functional unit. A controlled field experiment in a split-plot configuration was carried out to deliver the objective. Calculation of the total quantity of greenhouse gases emitted from the crop was carried out according to ISO 14040 and ISO 14044. Boundaries of the system encompassed the production and use of fertilizers and pesticides, the consumption of energy for agro-engineering activities and irrigation, as well as GHG emissions from soil resources and crop residue. The reference unit for the study was an object (plot) irrigated according to production practice in the area where the study was conducted. Under those conditions, greenhouse gas emissions totaled 75.68 kg CO² ⸱ t⁻¹ of the commercial product. Optimization, involving precise irrigation and fertilization using slow-release fertilizers, reduced the carbon footprint to 54.33 kg CO² ⸱ t⁻¹ of the commercial product. GHG emissions were thus reduced by 30%. The use of slow-release fertilizers resulted in a reduction of total greenhouse gas emissions per unit of marketable yield by 15% for non-irrigated crops and by 17% for irrigated crops. Irrigation, in turn, resulted in a reduction of total GHG emissions by 8% for conventional fertilization and by 11% for slow-release fertilization.

This study evaluated the response of two winter wheat lines: hypoallergenic wasko.gl− and control line wasko.gl+ to nitrogen (N) and sulfur (S) fertilization under field conditions in southern Poland during 2019–2021. A split-split-plot design with six N doses (0–120 kg ha⁻¹) and three S doses (0, 20, 40 kg ha⁻¹) was applied to assess grain yield, nitrogen agronomic efficiency (NAE), vegetation indices (LAI, NDVI), and grain protein content. Grain yields ranged from 3.92 to 6.08 Mg ha⁻¹, with the hypoallergenic line producing on average 16.6% more than the control one. Nitrogen fertilization significantly increased yields up to 80–100 kg N ha⁻¹, while sulfur application showed no consistent yield effect. The highest NAE was achieved at 80 kg N ha⁻¹, reaching 13.7 kg grain kg⁻¹ N for hypoallergenic and 19.6 kg grain kg⁻¹ N for the control wheat line. Remote sensing indices correlated with fertilization intensity; LAI and NDVI increased up to 80–100 kg N ha⁻¹, with optimal values differing between lines, confirming distinct nitrogen-use efficiencies. Grain protein content increased systematically with higher N inputs, exceeding 145.6 g kg⁻¹ DM at 120 kg N ha⁻¹; sulfur fertilization modified protein levels, with the optimal dose being 20 kg S ha⁻¹ for the hypoallergenic line and 40 kg S ha⁻¹ for the allergenic line. Results demonstrate that nitrogen supply strongly influences yield and quality traits, whereas sulfur plays a secondary role, particularly in modifying protein content in grains. Differences in genotype responses to fertilization emphasize the importance of taking an individualized approach to nitrogen and sulfur fertilization strategies, which are tailored to specific lines of wheat. This optimizes fertilization, yield, and quality, while maintaining environmental sustainability.

Macro- and microelements in waste can be returned to the soil as fertilizers and their sustainable use can reduce the need to extract natural resources. For example, the use of carbonate-clay flour, sewage sludge and waste sulfate sulfur to improve soil properties enables the natural recycling of the nutrients contained in these materials. Soil physicochemical properties with the application of waste and the bioavailability of nutrients and trace elements were assessed before and after a 3-month incubation period. This study showed that when carbonate-clay flour was applied alone or together with sewage sludge and waste sulfur, it improved the properties of the soil, inducing a reduction in acidification and an increase in the content of available P, K and Mg. Sewage sludge also provided Zn, Cu, Ni and Cr in addition to organic carbon. Sulfate did not cause soil acidification. The results indicate that the use of carbonate-clay flour alone, as well as with the addition of sewage sludge and sulfate sulfur, can be recommended for the deacidification of soil and serve as a remediation tool for, for example, the precipitation of chemical pollutants. The valorization of the waste used fits into the circular economy approach.

One of the assumptions of the circular economy is the introduction of nitrogen (N) fertilizers into soil in the form of by-products, such as urea fatty fraction (UFF). Another recommended sustainable agriculture treatment is to plough post-harvest straw into soil to improve the organic matter (OM) balance. We aimed to verify the efficacy of UFF as a N fertilizer applied with wheat or rape straw by examining its effect on the total carbon and N contents, pH, enzyme activity, OM mineralization and stabilization of soil. For this, we conducted a 120-day-long incubation experiment in which we compared the effect of UFF fertilizer applied with urea (both with and without a Ure inhibitor) on soil properties. Our main findings were that UFF acidified the soil (pH was lowered to 5.93) more than the urea (pH was above 6). Both fertilizers administered with straw slightly increased the soil carbon (to above 14 g kg⁻¹) and N contents (to around 1.4 g kg⁻¹) compared to the control treatment and caused an increase in enzyme activity at the beginning of the experiment, followed by a gradual decrease. The UFF application accelerated the OM decomposition, although urea had a more stabilizing effect on the OM expressed by larger (above 16%) areas occupied by stable, aggregated OM than UFF (below 10%). We concluded that UFF can replace urea as an environmentally friendly N fertilizer, and that it has a similar effect to urea on soil properties.

The study aimed to compare the effect of urea fatty fraction (UFF) and Pulrea^® (urea fertilizer) on plant yield and selected plant and soil parameters determined after the plants were harvested. UFF is a by-product of essential unsaturated fatty acids (UFAs) extraction from fish oil using urea, and Pulrea^® is a commercial urea fertilizer. Both products were applied to the soil and the leaves (foliar application). The effect of Pulrea^® on plant yield was generally stronger than that of UFF but depended on soil properties and plant species. Both fertilizers, but especially UFF, increased the total N content in the plant and effected nitrate accumulation. The plants used 45–90% of fertilizer nitrogen, with the plants generally using more N from Pulrea^® than from UFF. Higher nitrogen production efficiency was achieved using Pulrea^® than UFF and when plants were cultivated on medium soil than on light soil. Fertilizers increased the acidity and electrolytic conductivity of both soils but did not induce soil salinization. They increased the content of mineral nitrogen forms in soils, which was generally the case more in soil with Pulrea^® application than with UFF application. As a rule, the soil dehydrogenases activity did not change significantly or even decrease after fertilizer application. It was visibly higher in medium soil and after foliar Pulrea^® application than after foliar UFF application. This may be due to the content of accompanying substances in UFF that affect nitrogen absorption from this fertilizer. Based on the results, it cannot be clearly stated that one of the tested fertilizers had a better effect on the studied parameters. Generally, the less favorable effects of UFF compared to Pulrea^® may indicate the necessity of removing from UFF the accompanying substances that may adversely affect plants and soil microorganisms. This aspect needs to be investigated under controlled conditions in field experiments.

With a shortage of sulfur in the soil and an increasing world population and, thus, food consumption volume, the demand for this important nutrient is likely to increase, both globally and regionally. The purpose of this model incubation study was to evaluate the effect of fertilizer granule applications containing elemental sulfur, halloysite and phosphate rock on the content of the bioavailable form of sulfur and phosphorus, as well as dehydrogenase activity and pH value of two soils differing in granulometric composition and chemical parameters. In addition to the standard procedure of analysis of variance, the authors propose various methods of advanced statistical analysis: regression modeling, including simple regression and multiple regression, or multivariate methods of grouping objects and traits resulting in the creation of heatmaps. With respect to the control, the application of fertilizer granules generally had no significant effect on the content of available phosphorus and the activity of dehydrogenase, and had little effect on the degree of acidity of the soils tested. There was a greater effect of introducing fertilizer granules on the content of sulfate sulfur in heavy soil than in medium soil. Using advanced statistical techniques revealed relationships between the studied soil parameters and changes in their values as affected by the experimental factors.

A two-year pot experiment was set up to determine the ability of Actosol (Act) to improve soil properties and maize yields. The Act effects were compared to those of manure, nitrogen/phosphorus/potassium (NPK) and an additive-free control (Ctr). After years 1 and 2, the pH, sorption properties, total carbon (TC), total N (TN), available P and K contents, dehydrogenase activity (DHA), residuum (Re) and humic acids (HAs) were measured in coarse- and medium-textured soils. Maize yield, N, P and K were also quantified. The plant element uptake and soil quality index (SQI) were calculated. In both soil types, the Act increased the DHA, cation exchange capacity, bioavailable K, P, TC, TN, C HAs and C Re in the soils compared to the Ctr. The maize yield, K and P contents and their uptake by the maize increased in both soil types after Act application. The SQI increased by >50% with a single dose (Act1), almost doubling with a double dose (Act2) compared to the Ctr. With Act1 and Act2, the P and K uptake increased several-fold. The soil properties and maize yield after using Act demonstrated its utility in improving soil organic matter and maize growth and in disposing of waste.

Sulfur is a necessary nutrient for the proper functioning of living organisms, both plants and animals. However, following pro-environmental activities carried out for many years, there is now a deficit of this element in the soils of many countries. The aim of this model study was to determine the effect of the application of waste elemental sulfur and its mixtures with organic materials (cattle manure, digestate and biochar) on the availability of manganese and zinc in soils. In addition to the standard analysis of variance (ANOVA), the authors propose various methods of advanced statistical analysis, e.g., simplified linear or polynomial regression model development, multiple regression analysis, heatmap statistics and principal component analysis (PCA). The presented findings indicate significant relationships between the soil pH value, S-SO₄, Zn and Mn contents, dehydrogenase activity, and experimental duration. The results of regression analysis revealed that the applied materials had a more significant influence on the zinc content than on the manganese content during the incubation period.

Crop fertilization with sulfur is an important part of agricultural practices, as is the systematic increase in soil organic matter content. Materials of waste origin constitute a source of plant-available sulfur, as well as soil organic matter. The study was to verify the hypothesis assuming that combining waste sulfur pulp and its mixtures with organic materials enables simultaneous soil enrichment with readily available sulfur and organic matter. A 240-day incubation experiment was conducted, on two soils: very light and heavy; with two sulfur doses applied to each soil (20 and 40 mg S/kg d.m. for very light soil, and 30 and 60 mg S/kg d.m. for heavy soil). The sulfate sulfur content in the incubated soil material, treated with the addition of sulfur pulp and its mixtures with organic materials, increased significantly up to day 60 and then decreased. The application of these materials significantly increased the content of available sulfur and decreased the pH value of the incubated material. The effect of the introduced materials on dehydrogenase activity depended on soil granulometric composition (the impact of the applied materials on the activity of these enzymes in very light soil was small, and in heavy soil, their activity was usually limited by the presence of introduced materials). Application of the studied materials had little effect on the total organic carbon content in the incubated soil material (a significant change in the value of this parameter, in relation to the control soil, was recorded in some treatments of heavy soil).