Effect of Fertilization on Phenolics of Rapeseeds and Their Antioxidant Potential.

Three varieties of rapeseed (Castilla, California, and Nelson F1) were cultivated using medium-intensive (control), intensive, and economical (spare) technologies with different nitrogen and sulfur fertilization techniques. The antioxidant potential of rapeseeds was investigated using ABTS, FRAP, and DPPH assays. The content of total phenolic compounds was determined using the Folin-Ciocalteu phenol reagent. The profile of phenolic compounds was determined using high-performance liquid chromatography (HPLC). Diversifying fertilization in various ways influenced the content of phenolic compounds in extracts of rapeseed. In extracts from the Nelson F1 rapeseeds, intensive cultivation resulted in a lower content of phenolic compounds compared to the control group. Economic fertilization reduced the content of phenolic compounds in seeds from the California variety. HPLC chromatograms of the extracts were characterized by the presence of five (California and Castilla) and six (Nelson F1) main phenolic compounds. Two compounds were identified as sinapine and sinapic acid; others were classified as derivatives of sinapic acid. The effect of fertilization on the antioxidant activity of the seeds and their extracts varied depending on the plant variety and antioxidant assay. For the Castilla and California varieties, no differences were found in the results of the ABTS assay. The antiradical activity against ABTS•+ of extracts from the Nelson F1 intensive and spare cultivated seeds was higher than that of extracts from control seeds. The FRAP values of extracts/seeds from the Castilla variety cultivated using different methods did not differ significantly. The results of the DPPH assay were not affected by fertilization in the case of extracts from the California and Castilla varieties. However, the extracts from spare cultivated seeds of Nelson F1 exhibited stronger antiradical activity against DPPH•. These findings highlight the complex relationship between fertilization practices, phenolic compound accumulation, and antioxidant activity in rapeseed. Integrating varietal traits and cultivation practices is crucial for optimizing the nutritional benefits of rapeseed.

The effect of fertiliser treatments on the severity of Fusarium head blight and mycotoxin biosynthesis in winter rye.

The fungi of the genus Fusarium cause Fusarium head blight (FHB), a devastating disease that reduces grain yield and quality. They also produce mycotoxins which may pose a serious threat to human and animal health. This study investigated the effects of NPK fertilisation, foliar application of Cu, Zn, and Mn, applied separately and in combination, and of the Nano-Gro® organic growth stimulator on the occurrence of FHB in cultivar Dankowskie Diament rye based on the mycological analysis of kernels and on the concentrations of Fusarium mycotoxins in grain. The severity of FHB caused by seven species of the genus Fusarium was influenced by weather conditions in the analysed growing seasons. The applied fertilisation and the Nano-Gro® organic growth stimulator exerted varied effects on FHB development and the biosynthesis of Fusarium mycotoxins (deoxynivalenol, nivalenol, zearalenone and fumonisins) in grain. The greatest reduction in deoxynivalenol and nivalenol concentrations was noted in 2013, and the levels of moniliformin were lower in treated samples than in absolute control (untreated) samples in both years of the study. The severity of FHB positively correlated with the concentrations of zearalenone, deoxynivalenol, nivalenol, and moniliformin in the grain samples. Greater accumulation of ergosterol was noted in the rye grain harvested in 2013 than in 2012, and fertiliser treatment led to higher ergosterol concentrations than did control treatment.

Comparison of the phenolic compounds, carotenoids and tocochromanols content in wheat grain under organic and mineral fertilization regimes.

A field study was performed to evaluate the effect of mineral (NPK) and organic-based fertilizers such as compost (C), manure (FYM) and meat and bone meal (MBM) on the appearance (dimensions and color) of spring wheat kernels and on the total content in grain of main its phytochemicals (polyphenols, carotenoids and tocochromanols) and phenolic acids composition. Total phenolic compounds were determined using the Folin-Ciocalteu assay after alkaline hydrolysis of grain and carotenoids were analyzed spectrophotometrically. Composition of tocochromanols and phenolic acids was determined using RP-HPLC techniques. Only insignificant differences in the appearance of kernels and small changes in the content and composition of grain phytochemicals were noted between the studied fertilization systems. Among the analyzed phytochemicals the greatest variation was observed in the group of polyphenol compounds, with a stated increase of their total content of 6.7 and 11.2% in grain fertilized with MBM and compost, respectively. Simultaneously the grain from organic fertilization contained significantly less phenolic acids, and the decrease in their content ranged from 10.0% for FYM to 24.8% for MBM+EM-1. Organically and conventionally fertilized grain had similar amounts of tocochromanols and carotenoids. Comparison of MBM and MBM+EM-1 variants showed that application of effective microorganisms decreased carotenoids and tocochromanols content by 8.5 and 9.7%, respectively.