The objective of this study was to estimate how soil organic carbon influences winter wheat yield in the South Pannonian Basin. The treatments evaluated were: fertilized 3 year and 2 year crop rotation, fertilized wheat monoculture and unfertilized 3 year and 2 year crop rotation in the 38 years of continuous cropping (1970–2007). These treatments showed a declining trend of soil organic carbon in the 0–30 cm soil layer, respectively. On average, the plow-layer of the treatments lost 10% of soil organic carbon found at the beginning of the investigated period. The plow­layer of the unfertilized treatments reached a possible soil organic carbon threshold (1.16%) after balance on decomposition and formation was observed. We found that soil organic carbon preservation coupled with proper management such as crop rotation and fertilization is important for preserving soil productivity, and when soil organic carbon increases it could benefit winter wheat yield. Obtained results are valuable for developing a sustainable cropping technology for winter wheat and soil conservation.

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Marrubium vulgare is a cosmopolitan medicinal plant from the Lamiaceae family, which produces structurally highly diverse groups of secondary metabolites. A total of 160 compounds were determined in the volatiles from Serbia during two investigated years (2019 and 2020). The main components were E-caryophyllene, followed by germacrene D, α-humulene and α-copaene. All these compounds are from sesquiterpene hydrocarbons class which was dominant in both investigated years. This variation in volatiles composition could be a consequence of weather conditions, as in the case of other aromatic plants. According to the unrooted cluster tree with 37 samples of Marrubium sp. volatiles from literature and average values from this study, it could be said that there are several chemotypes: E-caryophyllene, β-bisabolene, α-pinene, β-farnesene, E-caryophyllene + caryophyllene oxide chemotype, and diverse (unclassified) chemotypes. However, occurring polymorphism could be consequence of adaptation to grow in different environment, especially ecological conditions such as humidity, temperature and altitude, as well as hybridization strongly affected the chemotypes. In addition, this paper aimed to obtain validated models for prediction of retention indices (RIs) of compounds isolated from M. vulgare volatiles. A total of 160 experimentally obtained RIs of volatile compounds was used to build the prediction models. The coefficients of determination were 0.956 and 0.964, demonstrating that these models could be used for predicting RIs, due to low prediction error and high r2.

This research studied the copper content of vineyard soils as affected by the long-term use of copper-based fungicides. The soil samples were taken from individual vineyards located in the central region of Serbia, from two depths: 0-30 and 30-60 cm. At the same time, at each site, control samples were collected from a nearby forest in order to determine the background concentrations. The pseudototal (CuT) and available (CuEDTA) copper content were analysed in 60 soil samples in total, 46 of which represented vineyard soils and 14 control samples. The maximum value of copper was 200.1 mg/kg of pseudototal and 82.1 mg/kg of available copper. Comparison of the copper content in vineyards to the background concentrations of control samples clearly confirmed anthropogenic influence. Out of 46 vineyard soil samples, about one half (22 of them) had the CuT concentration above the critical level of 60 mg/kg. Eleven samples had the pseudototal content over the MAC of 100 mg/kg. Anthropogenic influence was also confirmed on the basis of copper bioavailability and copper distribution along the soil profile. Available content of over 50 mg/kg was found in 8 out of 46 analysed samples of vineyard soils. According to the percentage contribution of available CuEDTA to pseudototalCuT, half of the samples were above 36%, which is potentially phytotoxic. The concentration of copper was the highest in the surface layer in the vineyard soil samples. A check of the background Cu levels has shown that the distribution of CuT and CuEDTA is uniform throughout the soil profile. Data from some of the analysed plots indicate that the process of erosion is under way at the site. The soil on lower-lying terrain has been found to be more exposed to copper pollution than the soil of higher terrain. Since copper at the surveyed sites is very persistent and accumulates in a short period of time, focus should be placed on the preventive measures of reducing the use of copperbased fungicides to an optimal level.

Camelina (Camelina sativa L.) is studied mostly as oil plant that can replace oilseed rape in the extensive agriculture. It is a good source of oil (40% oil in seeds) similar to sunflower, soybeans, canola, castor been and other oil crops. Oil of camelina is rich in essential omega 3 fatty acids. In addition, seed protein content is relatively high. Camelina has modest requirements for agro-ecological conditions and it is highly resistant to pathogens. Those features make camelina suitable for human nutrition and animal feed. Its use is related to sustainable agriculture, bio-diesel industry, coldpressed oils and the use of so-called marginal land. Examination of its ability to uptake and accumulate heavy metals (HM) is interesting from the standpoint of 1) food safety and 2) potential for phytoremediation. Hence, the aim of this study was to investigate the effect of HM on uptake and accumulation of some essential macro-and micronutrients and unwanted HM. Experiments were done with Camelina sativa L., cultivar Stepski 1. The seeds were exposed to 1 µM Cd or Cu and 10 µM Ni or Zn since the beginning of germination. Plants were grown in water cultures, in semicontrolled conditions of a greenhouse, on ½ strength Hoagland solution to which were added HM in the same concentrations as during germination. Concentrations and distribution of Ca, Mg, P, K, Fe and Mn in roots and shoots were altered in the presence of increased concentration of Cd, Cu, Ni and Zn.