Mineral nutrition and plant ontogeny influence both the physiological balance between nutrients in a plant and determine the proper nutritional status of a plant, which is necessary to realize the yielding potential of a cultivated species. The aim of the present study was to assess the effect of nitrogen doses (0, 4, 8, 12, 16 g N·m⁻²) and plant development phases (the beginning and full flowering) on the content of macroelements and changes in ionic ratios occurring in the herb of the summer savory cv. ‘Saturn’. The two-factor experiment was carried out in a random-block design with five replications. The mineral nitrogen nutrition applied increased the concentration of total nitrogen and its mineral forms in the plants. There was a change in ion homeostasis in the individual stages of the ontogenesis process, i.e., a higher content of P, K, Ca, and S in the initial flowering phase as well as Mg and Cl in the full flowering phase. The increase in the availability of mineral nitrogen in the soil solution caused a decrease in total sorption capacity, reducing the potential of the soil for saturation with alkaline cations.

The problem of fluoride toxicity to living organisms is the subject of many studies. Its effect, not always toxic, on the human organism has been well documented. However, although the phytotoxicity of the element has been proved, this issue is still being investigated. It seems to be still relevant due to the progressive pollution of the environment and fluoridation of water. Assuming that the source of food for humans is plants, the content of fluoride in fruits and vegetables is important for human health. In the available literature, fluoride has been demonstrated to be phytotoxic at the level of cell transformations, biometric plant parameters, development of resistance, and biochemical processes in plants. However, several studies have provided information on improvement of certain plant parameters, e.g., the length of roots or shoots, caused by low fluoride doses and improvement of respiratory indices. The aim of this study was to analyze changes caused in plants by exposure to fluoride and to determine its beneficial effects based on the latest literature reports. It was based on the latest knowledge from the last 8 years. Attempts were made to compare earlier research results with contemporary items. In conclusion, the analysis has shown that, although some sources provide information on the positive effect of small fluoride doses, the impact of this element requires further investigations, as has not been fully elucidated.

Background: This study of the large-flowered azalea cv. ‘Anneke’ investigated the impact of two factors, i.e., methods of fertilization and mycorrhization, on the nutritional status of plants during three years of nursery cultivation. Methods: Single mineral fertilizers, a slow-release fertilizer Hortiform pH (SRF), and fertigation in combination with mycorrhization of plants, were applied. Plant roots were inoculated with fungi from the genera Oidiodendron and Hymenoscyphus sp. The nutritional status of the large-flowered azalea in the first three years of cultivation was assessed based on macroelements. Results: The analyses revealed significantly higher content of nitrogen, phosphorus and calcium in the leaves of plants inoculated with fungal mycelium. A beneficial effect of plant mycorrhization on plant nutritional status, i.e., higher levels of nitrogen, phosphorus, potassium, calcium, and magnesium, was noted in the second and third years of azalea cultivation. Conclusions: Significant amounts of the nutrients were utilized in the middle of the growing season and almost fully utilized after the season. Hence, the necessity to supplement nutrients in each subsequent year of plant vegetation was postulated. Fertigation was shown to require further improvement of the nutrient solution.

Climate changes increase environmental stress pressure, limiting the yields of crops, e.g., strawberries. The green transformation introduced in the European Union, eliminating the use of chemical plant protection agents, requires the development of a technology that will simultaneously mitigate stresses and increase plant yields. The basis of this type of technology may be the targeted application of stabilized orthosilicic acid. The validation of this silicon-based technology was carried out through the pot cultivation of strawberries cv. ‘Falco’ in controlled conditions, compatible with their production. The experiment consisted of the foliar and intra-root (A) application of stabilized orthosilicic acid at concentrations of 0, 240, and 360 g Si·ha⁻¹ (B). A significant increase in the total and marketable yield, the weight of single fruits, and the number of fruits in the silicon-treated variants was noted in this study. The intra-root application of silicon had a more potent effect on the yield performance than foliar feeding. The intra-root application of the tested silicon doses significantly reduced the occurrence of gray mold (Botrytis cinerea) during the fruit harvest period. The application of the tested silicon doses in strawberry cultivation exerted a positive effect on the post-harvest shelf life of the fruits. Higher levels of Lascorbic acid, nitrates (V), and TSS were determined in strawberry fruits treated with stabilized orthosilicic acid. The leaves of plants treated with stabilized orthosilicic acid had lower contents of nitrogen, calcium, magnesium, iron, manganese, zinc, and boron and higher levels of potassium and copper.

In the cultivation of herbal plants, besides the size of the crop, the quality of obtained raw material is extremely important, which is proven not only by the appearance and taste, but also biological value. Factors that affect these parameters include plant nutrition. The main nutrient affecting the correct course of metabolic processes in a plant is potassium. To obtain high yield in terms of quantity and quality, the nutritional requirements of plants must be met. The aim of the study was to determine the effect of potassium nutrition on the quality of basil herb. The experiment was established in a two-factor scheme, in which the factors were: potassium dose (0.5, 1.0, 1.5 g K·dm–3) and the type of potassium fertilizer (KCl, K2SO4, KCl + K2SO4). The yield of basil plants was influenced by the dose and type of potassium fertilizers used (0.5 g K·dm–3 – 92.5; 1.0 g K – 67.3; 1.5 g K – 69.75 g·plant–1). The highest content of L-ascorbic acid was found in basil plants fed with the average potassium dose (65.9 mg·100 g–1 FW). The least nitrates (V) were contained in basil fertilized with KCl in the highest dose of K (63 mg·100 g–1 FW). No effect of the dose and type of potassium fertilizer on the content of phosphorus and sulfur in the plant material, was recorded. The content of Ca and Mg was influenced by both the potassium dose and the type of potassium fertilizer. The most of these components was revealed by plants fed with KCl, and with the increase of the dose, the content of both these mineral components decreased. Chlorine content in the herb increased with the applied potassium dose, the effect on the concentration of chlorine in the plant material was exerted by the type of potassium fertilizer applied – the highest concentration of this element was recorded. The content of macroelements in the substrate from basil cultivation was influenced by the dose and type of potassium fertilizers used. The best quality parameters of basil were obtained after application of 1.0 g K·dm–3 substrate in the form of KCl + K2SO4.

Fluorine is a common element in nature; however, the difference between a beneficial dose and a toxic dose for the organisms is small. The main source of fluoride for humans is water in addition to food. The aim of this study was to estimate the degree of severity of pathological changes, namely, caries or fluorosis, in the mineralized tooth tissue of 15-year-old adolescents with respect to their hygienic and nutritional habits, and the content of fluorine in drinking water, soil and plant products. 100 adolescents aged 15 from schools in Sosniłka, L'viv region, were examined. The condition of mineralized tooth tissue was evaluated by the caries severity, expressed by the mean number D3MFT, caries frequency and value of the SIC index. Fluorine in plant material and soil were determined according to the PN-G-04543:1982 standard, and water according to the PN-EN ISO 10304 - 1: 2009+ AC: 2012 standard. Severity of caries disease expressed by the D3MFT number in the examined group of 15-year-olds was 3.39; in the group of girls - 3.08, and in the group of boys - 3.76. In the examined group, the average number of teeth with fluorosis was 7.59. Value of the SIC index among the examined population of students (n-31) was 6.26: 5.89 (n-18) for girls and 7.31 (n-13) for boys. Fluorine concentration in the water was 0.78 - 1.25(mg·dm-3). In the soil, it also did not vary across the sampled areas and amounted, on average, to 176 mg·dm-3. The biggest fluorine content noted in the dry mass of beetroots was 3.50 (mg F· kg), and the lowest - 3.34 (mg F· kg). Close to optimal fluorine content lowers caries severity and frequency of fluorosis. Optimal fluorine content in drinking water and food does not require additional diet supplementation.