The aim of the study was to evaluate the effect of nitrogen nutrition on the content of fatty acids and selected qualitative parameters (nitrogenous substances, ash, crude fiber) in winter oilseed rape (Brassica napus L.). The experiment was carried out at the Vígľaš—Pstruša Research and Breeding Station in 2008–2009 and 2009–2010 by complete block design with four repetitions. Nitrogen fertilization was applied at four levels, plus an untreated control (after agrochemical soil analysis) by DAN 27 (Dolomite Ammonium Nitrate): 100, 120, 140, and 160 kg/ha N. Application date was in BBCH scale phase 59–60. The fatty acid contents (MUFA—monosaturated fatty acids; PUFA—polyunsaturated fatty acids) were determined by gas chromatography in the extracted fat, which is determined by extraction method. Within the result evaluation, statistically significant increases in the contents of linoleic and linolenic acids were recorded in all variants treated by nitrogen fertilizer, which is positive in terms of the use of rapeseed oil for food and energy purposes. The statistically significant decrease of oleic acid after the application of nitrogen fertilizers is negative for industry use of rapeseed oil.

Selenium effect on wheat grain yield and quality applied in different growth stages | Alexandra Zapletalová, Ladislav Ducsay, Marek Slepčan, Mária Vicianová, Peter Hozlár, Rastislav Bušo | Agricultural Journals

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, the scientific journal of the Mendel University in Brno, Czech Republic

Drought and high temperatures are among most dangerous attributes of climate change, which negatively affects the quantity and quality of sugar beet production. One of the most effective tools for eliminating unwanted effects is the application of biostimulants during the growing season. In this study, a 4 × 3 factorial scheme was adopted: Two biostimulant treatments, namely (i) pure extract from brown seaweed Ascophylum nodosum (B1) and (ii) concentrate from the seaweed Ascophylum nodosum and humus substances (B2), were compared to a control treatment (B0) in an experiment with four sugar beet varieties (Fischer, Fabius, Nicolaus, Lucius). The two-year research proved the significant influence of biostimulants on all monitored physiological and production parameters of sugar beet, with the exception of potassium content. Biostimulants positively influenced the results of root yield, polarized and white sugar yield, and the values of LAI (leaf area index), NDVI (normalized difference vegetation index), and PRI (photochemical reflectance index), while the positive effect on sugar content was only in the case of B1 treatment. The production potential fluctuated significantly depending on the observed interaction, but it can be concluded that the most limiting factor of production is the course of weather conditions. However, after treatment with biostimulants, an increased root yield (B2) and sugar content (B1) were found. Moreover, in this experiment, a strong positive relationship between root yield and physiological parameters (NDVI and PRI) and LAI was proven, while the relationship of sugar content to these parameters was weak. Monitoring of the physiological response to biostimulant application shows a high potential from the sustainability perspective in the context of sugar beet production. In addition, the impact on the height and quality of production was evident.

Sunflower (Helianthus annuus L.) is grown in Slovak growing conditions for edible oil of high quality, its composition of unsaturated fatty acids affects the human health positively. Influence of year, hybrids (Marbelia CS and Reasun DS-5) and biostimulating preparations (Florone and Fertisiline) on yield, oil content, and amount of selected fatty acids (oleic, linoleic, palmitic, and stearic acids) was find out in this study. Also evaluate the relationship within the achieved yield and oil content with the obtained amount of selected fatty acids. Field small-plot experiments were established by randomized split plot method during the growing years of 2018 and 2019. The experimental field is situated in a warm maize production area, while the course of weather conditions during individual growing seasons was different. On an average for experimental period of 2018-2019, more favorable course of temperatures and precipitation was recorded in 2018. Significantly higher achene yield (3.29±0.35 t/ha) and a higher amount of selected fatty acids (oleic acid 62.11±4.33%; linoleic acid 45.32±4.62%; palmitic acid 5.26±0.33%; stearic acid 4.21±0.20%) were found in Reasun DS-5 hybrid. Both biostimulating preparations had a significant effect on the yield and oleic acid content, when both biostimulators were applied in BBCH 15 and BBCH 55. The amount of linoleic acid decreased by both biostimulating applications in BBCH 15 (Florone 33.88±10.57%; Fertilisine 34.11±13.37%) and BBCH 15, 55 ((Florone 34.08±12.34%; Fertisiline 34.26±13.40%) compared by control treatments (38.43±6.01%). The contents of linoleic acid on treated variants by both preparations in BBCH 55 (Florone 38.26±9.47%; Fertisiline 39.03±8.95%) were statistically non-significant with comparison to untreated control. The height of yield was negatively correlated (r= -0.310; P<0.01) with the oil content in the average of 2018 and 2019. A significant positive correlation was found in the relationships between the yield and palmitic acid (r=0.35; P<0.01), linoleic acid and palmitic acid, and stearic acid (r=0.51; P<0.01) (r=0.86; P<0.01), palmitic acid and stearic acid (r=0.45; P<0.01).

The soil application of essential trace elements, such as selenium and its various agrochemical species, presents a real challenge for modern agriculture. However, unknown exceeding threshold concentrations could target potential toxicity within the soil–plant–organism. When applied at optimal levels and combined with the common buckwheat—a crop of the future known for its high nutritional value—this poses a novel academic approach. Therefore, the aim of this research is to examine the effect of three concentrations (150, 300, and 600 g/ha) of selenium species (sodium selenite and sodium selenate) on mobility and distribution within the common buckwheat plant, including its impact on the biofortification. The research was carried out during the 2022 and 2023 seasons through pot experiments in semi-regulated conditions located in the Central European agronomic region. Following manual harvesting, chemical analysis was conducted using methods such as atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS), along with yield determination. The results confirmed the positive effect of Se⁶⁺ 150 g/ha and Se⁴⁺ 150 g/ha and 300 g/ha on seed yield. Oppositely, Se⁶⁺ 600 g/ha caused a decrease in seed yield of 23.87%. For biofortification of common buckwheat is most suitable Se⁶⁺ in a dose of 150 g/ha, where the Se content in seeds, 3.30 ± 0.46 mg/kg, was achieved. The soil fertility index, based on PCA, indicated that Se⁶⁺ at 150 g/ha exhibited the highest biofortification efficiency without compromising yield.