Seasonal variations in the environment (e.g. of temperature and light intensity) can lead to the excess production of reactive oxygen species and oxidative stress, inducing changes in the permeability of the plant cell membrane and the structure and function of cellular molecules. To address these deleterious effects, plants activate various non-enzymatic and enzymatic antioxidants. This study seeks to detect the influence of seasonal variation in Hedera helix (ivy) leaves, collected in Banj brdo (Banja Luka, Republika Srpska, Bosnia and Herzegovina) between December 2017 and November 2018, on oxidative (hydrogen peroxide and malondialdehyde) and antioxidant (superoxide dismutase, catalase, Class III peroxidases, and phenolic compounds) parameters. During the winter-early spring months (a temperature range of 0.7 to 5.4?C), we detected an increase in the values of all the oxidative and antioxidant parameters, whereas during the spring, summer, and autumn months (a temperature range of 15 to 25?C), the values of most of these parameters fell. However, a peak in the parameter values was detected during June and July 2018, which might be attributable to the influence of the changes in both light intensity and temperature and to the effects of intensive shoot growth. Our results highlight the importance of the antioxidant protection system of H. helix for its acclimation to seasonal variations in the environment, especially temperature.

This study focused on a landfill flotation tailing pond of the “Ljubija” iron ore mine, which is habitat covered by sparse vegetation consisted by specific plant groups. The following plant species were selected: Rumex hydrolapathum, Silene vulgaris, Tussilago farfara, Arabis hirsuta, Acer pseudoplatanus and Populus alba. The plants were collected and processed for the determination of the content of toxic metals (Fe, Zn, Cu, Mn, Ni, and Cr) aiming to evaluate their phytoremediation potential. At the same time, the content of toxic metals in the soil was analyzed to determine the degree of loading and the possibility of cleaning the area with phytoremediation techniques. The sequence of bioaccumulation in the tissue of all examined species decreased in the order Fe > Mn > Zn > Cu > Ni > Cr. The values of phytoaccumulation factors BCF and BAC for all investigated elements were below 1, except for Fe and Mn, which indicates a medium to poor accumulation potential of the investigated species. An exception was recorded in the plant A. hirsuta where BCF > 1 for Cr. The translocation coefficient (TA > 1) for Cu and Mn was determined for R. hydrolapathum, for Cu and Zn in A. pseudoplatanus, for Cu, Zn, and Ni in T. farfara, and Zn in A. hirsuta, which classifies these species as effective in techniques of phytostabilization of the researched area. These data are the first research in the area of the Iron Ore Mine Ljubija, which is of great interest to determine the level of contamination of soil and plants with toxic metals, and to remediate the same with phytoremediation techniques.

In this study, changes in Class III peroxidase (POX) and polyphenol oxidase (PPO) activity in Phragmites australis (Cav.) Trin. Ex Steud. Utricularia vulgaris L. and Salvinia natans (L.) from the Bardača wetland during one vegetation season (June-October) were monitored. The highest activities of soluble and ionic cell wall bound peroxidases (solPOX and ionPOX, respectively) were measured for Phragmites communis (leaf > root > rhizome), followed by Utricularia vulgaris (whole plant), then Salvinia natans (whole plant). The results showed that during the vegetation period (August-September) the activity of solPOX, ionPOX and PPO in Phragmites communis increased, but the activity decreased drastically in October. For Salvinia natans and Utricularia vulgaris, a different seasonal distribution was obtained in the PPO activity, i.e. with a maximum activity during July and a minimum one during September. Different seasonal trends in enzyme activities are probably the result of abiotic stress caused by changing physic-chemical environmental conditions and different adaptive capacities of the studied species to habitat conditions. Correlations between physicochemical environmental parameters and enzyme activities indicate the possibility of using POX and PPO activities as an important bioindicatos of environmental status.

In the study, the morphological and structural properties of bunches and berries, as well as the chemical characterisation of three interspecific grapevine cultivars—‘Bronner’, ‘Muscaris’, and ‘Morava’—were studied. Sugars and organic acids in the grapes were analysed using high-performance liquid chromatography (HPLC), while phenolic compounds were analysed by HPLC–mass spectrometry. ‘Morava’ and ‘Muscaris’ showed higher Hue angle values, indicating a greener skin coloration compared with ‘Bronner’, which exhibited a more yellow skin colour. ‘Muscaris’ and ‘Bronner’ had higher bunch weights than ‘Morava’, while the 100-berry weight did not differ significantly among the varieties. ‘Bronner’ must had the highest titratable acidity, and ‘Muscaris’ had the highest sugar content. Flavanols were the main phenolic compounds in the grapes, accounting for 76–88% of the total phenolic content. The highest concentrations of flavanols and caftaric acid were found in ‘Bronner’ and ‘Muscaris’ berries, while ‘Morava’ had the highest flavonol content. All studied varieties achieved good grape and must quality and are therefore recommended for wine production. ‘Bronner’ and ‘Muscaris’ stood out for their high bunch weight and high concentrations of flavanols and total phenolics, which contribute significantly to wine taste and overall quality. ‘Muscaris’ berries had a high sugar content, making this variety suitable for producing wines with higher alcohol content. In contrast, ‘Bronner’ is recommended for wines requiring higher acidity levels.