Cocoa beans are part of the cocoa plant fruit (Theobroma cacao L.) used to prepare various products such as chocolate, cocoa butter, jelly, liqueurs, cosmetics, etc. Dark chocolate is consumed worldwide by different populations and is known for its good taste, making it one of the most favoured food products. This work aimed to determine the content of total polyphenols (TPC), total flavonoids (TFC), and the antioxidant potential measured through the ability to scavenge DPPH free radicals (DPPH), ferric reducing power (FRAP), and total antioxidant capacity (TAC), as well as major and trace elements contained in twelve commercially available dark chocolate samples, with cocoa content ranging from 40% to 99%. The total polyphenols content ranged between 10.55 and 39.82 mg/g GAE, while the total flavonoid content was from 10.04 to 37.85 mg/g CE. All applied antioxidant assays indicate that the sample with the highest cocoa percentage shows the greatest antioxidant activity (DPPH: 48.34% of inhibition; FRAP: 89.00 mg/g GAE; TAC: 83.86 mg/g AAE). Statistical methods were applied to establish the differences between the samples concerning TPC, TFC, DPPH, FRAP and TAC, as well as to differentiate the samples according to the mineral content. The results indicated that the differences in TPC and TFC between different samples depended on the cocoa content and the addition of dried fruit pieces. A good correlation between antioxidant potency composite index (ACI) and declared cocoa content was noticed (R2 = 0.8034), indicating that the declared percentage of cocoa is a reliable indicator for antioxidant activity of analysed dark chocolate samples. The nutritional evaluation proved that the studied chocolate samples were an excellent source of Mg, Fe, Mn and Cu.
The aim of this study was to investigate the effects of different LED lights on the growth of cauliflower microgreens and to determine which combination of LED light best increases tolerance to salt stress and promotes the growth and accumulation of secondary antioxidants in the presence of salt stress in vitro. Plants were grown in a growth chamber under different LED light treatments (red light, blue light, a combination of red and blue light, and cool white light) and in MS media with different NaCl concentrations (0, 50, and 100 mM). The effects of the different light qualities and salt stress conditions on growth, content of photosynthetic pigment, flavonoids, phenol, proline, and antioxidant enzyme activity were measured. The best treatments for microgreen development, according to the data, were those that combined red and blue light. In addition to increasing stress tolerance and enabling plant growth at a lower salt concentration (50 mM NaCl), the combination of blue and red light also enhanced the synthesis and accumulation of secondary metabolites and the antioxidant potential of microgreens grown in vitro, which may have nutritional and pharmaceutical value.
The accumulation of heavy metals in the environment is one of the most significant environmental problems due to the potential risk to human and animal health. The aim of this study was to analyze the influence of the distance from the industrial zone on the heavy metal content in the soil and vegetative parts of wheat. A field experiment with four wheat genotypes was conducted in the area of the city of Pancevo, Serbia, at three locations at different distances from the industrial zone. By atomic absorption spectrophotometry (AAS), concentrations of five heavy metals (Zn, Pb, Cr, Cu, and Cd) were determined in the soil and wheat. The highest total content of Zn, Cr, Cu, and Cd in the soil (72.5, 27.3, 26.2, and 0.3 mg kg−1, respectively) was found at the location closest to the industrial zone, while the highest content of Pb (28.9 mg kg−1) was recorded at a location that is in the immediate vicinity of a road. Heatmap correlations and PCA analysis show a significant relationship between the content of heavy metals in the soil and the plant. Genotype Pobeda had the lowest content of Cr, Cu, and Cd in the root and the lowest content of all the analyzed heavy metals in the stem. The highest translocation factor of heavy metals was found in the genotype Apache, which had the highest content of Pb, Cr, and Cu in the stem. The highest heavy metal bioaccumulation and translocation were established for Cd content (0.86 and 1.93). The obtained results indicate a potential ecological risk in the immediate vicinity of the industrial zone, while the difference in the accumulation of heavy metals between the studied genotypes opens new aspects for breeding programs.
In the face of increasing climate variability, understanding the dynamics of plant-to-plant interactions within crops is becoming increasingly important. This study aimed to examine plant responses to varying intensities of inter-plant competition, induced bz different planting densities, to enhance the accuracy of future yield prediction models. Six hybrids were grown at three planting densities (S1, S4, S7). Grain yield and yield components were estimated at four developmental points during grain filling (V1 to V4). These regression models and machine learning (ML) were applied to predict maize production under variable weather conditions. The factor year was the main source of variability, with less favourable conditions in the second year (G2) reducing yield by approximately 1–2%. Lower planting density (S1) improved individual plant development and yield components, while maximum density (S7) resulted in higher grain yield despite reduced individual performance. Hybrid H5 showed strong tolerance to high density, producing the highest yield under S7 conditions. Machine learning models accurately predicted key seed quality traits—moisture, oil, and protein—with performance metrics exceeding 80% accuracy. Specifically, R2 values reached 0.82 for moisture content and 0.77 for oil concentration, indicating strong predictive capability. These findings support careful selection of hybrids and optimal planting density strategies in future cropping systems to increase yield and maintain seed quality in different environments.
Summary: Considering that agricultural production needs to be adjusted to global climate changes, it is of particular importance to develop bread wheat germplasm with improved tolerance to abiotic stress conditions. Therefore, the aim of this research was to identify stable wheat genotypes with increased salinity stress tolerance. The experiment was conducted with 27 wheat genotypes, at two localities: Kumane (solonetz soil type) and Rimski Šančevi (chernozem soil type) during two growing seasons. A significant influence of genotype and environment, as well as G × E interaction, on the phenotypic expression of yield components was found. The factor of genotype had the largest effect on the variation in plant height (38.7%) and the smallest effect on the variation in the number of grains per spike (8.24%). The greatest influence of the environment (64.7%) and G × E interaction (17.44%) was found in the variation in the number of grains per spike. Salinity conditions contributed the most to the decrease in the number of grains per spike (30%), which is considered the best indicator of the impact of stress on the plant. The smallest decrease in the number of grains per spike was recorded in the genotypes Šumadija (16.0%) and Harmonija (18.8%). However, AMMI and PCA analyses showed that the genotype Harmonija is characterized by a higher value of the number of grains per spike and greater stability. The genotypes Renesansa, Jugoslavija, Bankut 1205, and Harmonija were characterized by the smallest reduction in plant height under salinity conditions, among which Jugoslavija and Renesansa exhibited high stability and lower trait values. The smallest reduction in spike length was found in the genotypes Jugoslavija and Šumadija, which exhibited the specific adaptability to salinity stress. In terms of salinity tolerance, the genotypes Šumadija, Harmonija, and Renesansa are considered valuable genetic resources in breeding programs.