Ždralovac peatland in the karst field Livanjsko polje in southwestern Bosnia and Herzegovina with an area of about 3.500 ha has always been drained and used for the regional people. But drainage, agriculture and climate change cause the peat drying in the summer and create the conditions for frequent fires and serious changes of peat properties. Since 1.000 ha of peatland was used for agriculture (abandoned areas for 25 years that are being cultivated again today), and the extracted peat is used as a raw material for the plant growing substrate. The presence of certain pollutants is a good indicator of the suitability of peat for the plant production. In this paper, the state of peat related to contamination with heavy metals, polycyclic aromatic hydrocarbons - PAHs and pesticide residues was investigated in undrained peat areas, reclamation areas and peat burning sites. The presence of heavy metals in concentrations higher than permitted was not recorded. The presence of combustion products PAHs was recorded on all surfaces, but only naphthalene exceeds the permitted concentrations of organic pollutants. Only pesticide residue of dichlorodiphenyltrichloroethane (DDT) was recorded in abandoned meliorated areas used in agriculture, and the concentration exceeded the level of uncontaminated land.

Many heavy metals (HMs) are essential micronutrients for the growth and development of plants. However, human activities such as mining, smelting, waste disposal, and industrial processes have led to toxic levels of HMs in soil. Fortunately, many plant species have developed incredible adaptive mechanisms to survive and thrive in such harsh environments. As a widespread and ruderal species, Geranium robertianum L. inhabits versatile soil types, both polluted and unpolluted. Considering the ubiquity of G . robertianum , the study aimed to determine whether geographically distant populations can tolerate HMs. We collected soil and plant samples from serpentine, an anthropogenic heavy metal contaminated, and a non-metalliferous site to study the physiological state of G. robertianum . HMs in soil and plants were determined using flame atomic absorption spectrometry. Spectrophotometric methods were used to measure the total content of chlorophylls a and b, total phenolics, phenolic acids, flavonoids, and proline. Principal component analysis (PCA) was used to investigate the potential correlation between HMs concentrations gathered from various soil types and plant samples and biochemical data acquired for plant material. A statistically significant difference was observed for all localities regarding secondary metabolite parameters. A positive correlation between Ni and Zn in soil and Ni and Zn in plant matter was observed ( p <0.0005) indicating higher absorption. Regardless of high concentrations of heavy metals in investigated soils, G. robertianum displayed resilience and was capable of thriving. These results may be ascribed to several protective mechanisms that allow G. robertianum to express normal growth and development and act as a pioneer species.

Vine-leaved kitaibelia (Kitaibela vitifolia Willd.), also known as balkanmalva or chalice flower, is a critically endangered plant species with a high risk of extinction in the wild. A reason given for this is, among others, a low germination rate primarily caused by dormancy. The present study evaluated the seed germination and seedling growth parameters of vine-leaved kitaibelia in response to eight different pre-sowing treatments. The final germination percentage ranged from 0 % to 55 %, depending on the pre-sowing treatment. The most effective method for breaking dormancy and increasing vine-leaved kitaibelia seed germination was the treatment with seeds soaked in H2SO4 for 5 min. The mechanical scarification of vine-leaved kitaibelia seeds also improved germination as compared to control treatment, while treatments with nitric acid and gibberellic acid were not effective in enhancing seed germination. All evaluated seedling growth parameters were not affected by pre-sowing treatments. Considering that successful germination and seedling establishment are crucial for the regeneration of vine-leaved kitaibelia further studies are required in order to identify other pre-sowing treatments that could further enhance seed germination and, consequently, seedling development.

Stress caused by drought induces plant morphology, biochemistry, and physiology changes, leading to considerable reductions in plant growth and productivity. This study aimed to evaluate the antioxidant defence system of impatiens seedlings (Impatiens walleriana L.) under drought. The antioxidant response of impatiens to drought was evaluated using following parameters: the activity of catalase, guaiacol peroxidase, pyrogallol peroxidase and ascorbate peroxidase, total phenolic and flavonoids contents and total antioxidant capacity. The experiment was conducted during 2020 in a greenhouse under controlled conditions. Half of the impatiens seedlings (20 plants), after the acclimation period in the greenhouse, were exposed to drought for a period of five days, while the second half was not (20 plants were regularly watered). The results of the study showed that the exposure of impatiens seedlings to drought increased the activity of enzymatic components, total phenolics and flavonoids contents and total antioxidant capacity of leaves. Greater exposure of impatiens to drought (in the observed period) implied a higher plant enzymatic and non-enzymatic antioxidant defence system activity. These results confirm that impatiens has evolved both enzymatic and non-enzymatic antioxidant defence mechanisms to adapt and survive the short-term drought exposure.

The aim of this study was to compare the yield and fruit quality characteristics of raspberry (Rubus idaeus L.) cultivar ʽMeeker' grown in organic and conventional cultivation systems. The total soluble solids, titratable acidity, ascorbic acid content, total phenolic and flavonoid contents and total antioxidant capacity of raspberry fruits were assessed. The analyses showed that raspberry yields per cane were significantly higher in the conventional cultivation system. In contrast, fruits from organic farming had higher antioxidant levels. The findings of this study indicated that organic farming in the study region increased raspberry quality, but decreased yield, as compared to conventional farming.

Summary The aim of this study was to examine the effects of seaweed extract (Algaren), nettle extract and microbial biostimulant (Slavol) on total phenolics and flavonoids and antioxidant capacity of leaves of lavender ( Lavandula officinalis L.), sage ( Salvia officinalis L.) and basil ( Ocimum basilicum L.). The study was carried out in a greenhouse located in Vitez, Bosnia and Herzegovina. The experimental trial was set up in a randomized block design with four biostimulant treatments in three replications. The first application of biostimulant was carried out immediately after the transplanting of seedlings, and the second and third treatments 15 and 30 days later, respectively. Total phenolic and flavonoid contents and ferric-reducing/ antioxidant power (FRAP) assay were used to evaluate the antioxidant properties of each leaf extract. The nettle extract was found to be the most effective in increasing total phenolics, flavonoids, and antioxidant capacity in leaves of studied plants. In this study, the antioxidant capacity of leaf extracts was in line with total phenolics/flavonoids, regardless of plant species and biostimulant treatments, suggesting that phenolic compounds greatly contribute to antioxidant capacity of studied plants.

The aim of this study was to study the impact of crop load on the yield and grape quality of ‘Merlot’ and ‘Vranac’ (Vitis vinifera L.) in Trebinje vineyard. The crop load levels studied in this trial were 9 buds (V1) and 12 buds (V2) per vine at each variety trained on Lenz-Moser bilateral cordon system. The impact was determined by measurements of yield per vine and grape quality characterized by the contents of total soluble solids, titratable acidity, total phenolics, total flavonoids and by total antioxidant capacity. The measured parameters of grape quality of ‘Merlot’ and ‘Vranac’ were not influenced significantly by crop load levels. V2, compared to the V1, showed the potential for increasing grape yield only for Merlot variety under experimental conditions. The results of this study also showed a positive correlation between total phenolics/flavonoids and total antioxidant capacity of grape berries in both varieties, regardless of crop loads applied.