Selenium (Se) is an essential micronutrient of fundamental importance to human health and the main Se source is from plant-derived foods. Plants mainly take up Se as selenate (SeO₄²⁻), through the root sulfate transport system, because of their chemical similarity. The aims of this study were (1) to characterize the interaction between Se and S during the root uptake process, by measuring the expression of genes coding for high-affinity sulfate transporters and (2) to explore the possibility of increasing plant capability to take up Se by modulating S availability in the growth medium. We selected different tetraploid wheat genotypes as model plants, including a modern genotype, Svevo (Triticum turgidum ssp. durum), and three ancient Khorasan wheats, Kamut, Turanicum 21, and Etrusco (Triticum turgidum ssp. turanicum). The plants were cultivated hydroponically for 20 days in the presence of two sulfate levels, adequate (S = 1.2 mM) and limiting (L = 0.06 mM), and three selenate levels (0, 10, 50 μM). Our findings clearly showed the differential expression of genes encoding the two high-affinity transporters (TdSultr1.1 and TdSultr1.3), which are involved in the primary uptake of sulfate from the rhizosphere. Interestingly, Se accumulation in shoots was higher when S was limited in the nutrient solution.

The continuous growth of the population, along with climate change and the resulting surge in food demand, requires the development of alternative crop cultivation strategies that reduce the excessive use of freshwater for agricultural purposes. Biochar, which is a carbon-rich material made from organic waste through pyrolysis, has been recommended as a potential soil amendment to mitigate the negative effects of salinity. Biochar has unique properties such as high porosity, an ion exchange capacity, and the ability to retain water and nutrients. The purpose of this study was to evaluate the feasibility and effectiveness of using saline water for the cultivation of tomato plants (Solanum lycopersicum L.) and to investigate the potential use of biochar as a mitigation strategy for salinity-related issues in tomato cultivation. The concentration of NaCl during the experiment was 100 mM. We examined the impact of salt stress on plant growth, protein and chlorophyll content, the activation of the antioxidant response, and nutritional status. Our results indicated that salt treatments led to a significant accumulation of Na and Cl in shoots (regardless of the biochar addition) but did not result in a corresponding reduction in plant growth. However, the degree of oxidative damage caused by NaCl treatment, measured as malondialdehyde (MDA) accumulation, was reduced by biochar addition to the growth medium, most likely because of an increased guaiacol peroxidase (GPX) activity, which led to lower MDA accumulation. The strong positive effect of biochar on GPX activity could be reasonably attributed to increased Mo accumulation. In conclusion, the findings of this study represent a valuable starting point for developing crop management strategies based on biochar application to enhance plant performance under unfavorable conditions and reduce freshwater dependence in agriculture.

This study investigated the potential of biogenic ZnO nanoparticles (ZnO-NPs) to alleviate cadmium (Cd) toxicity in durum wheat plants exposed for 14 days to 25 μM CdSO₄. By applying ZnO-NPs at two different concentrations (25 and 50 mg L⁻¹), we observed increased chlorophyll content, beneficially impacting the photosynthetic efficiency, and enhanced sulfur, zinc, and iron accumulation. Moreover, the ZnO-NP treatment reduced the Cd accumulation in shoots, mitigating leaf chlorosis and oxidative damage. This response was clearly mediated by the increased thiol and phytochelatin production, as well as the enhanced sulfate uptake rate, with TdSultr1.3 as the most responsive gene coding for high-affinity transporter to Cd stress. In conclusion, the application of biogenic ZnO-NPs appears to be a promising approach for reducing the uptake of heavy metals by plants. In addition, it could be successfully used in combination with contamination prevention measures and/or remediation of contaminated sites to remove and mitigate the harmful effects of Cd on the environment and human health.

Olive Quick Decline Syndrome (OQDS), caused by the bacterium Xylella fastidiosa, subsp. pauca, has devastated olive groves in Italy’s Apulia region since 2013. Despite significant scientific progress, the solution remains elusive. This study investigated the link between olive tree nutritional status and OQDS severity, aiming to uncover potential mitigation strategies. We analyzed leaf nutrient profiles from olive trees in naturally infected areas, categorizing them as asymptomatic (AS), mildly symptomatic (MS), or severely symptomatic (SS). Distinct nutritional differences were observed across these groups. The integration of univariate statistical analysis, hierarchical clustering, and Principal Component Analysis (PCA) revealed a complex relationship between plant nutritional status and disease progression. Notably, the PCA results highlighted the importance of sulfur metabolism, suggesting its role in olive trees’ defense mechanisms and metabolic responses to OQDS. These results provide promising evidence with potential application for dealing with OQDS, and the question of whether plant nutritional status plays a role in the development of OQDS symptoms deserves to be further examined in depth.

Summary: Reciprocal iron–sulfur regulation in durum wheat converges on a few metabolic hubs that integrate nutrient status with plant growth and performance. Iron and sulfur availabilities were factorially modulated in hydroponically grown wheat to establish how each nutrient and their interaction shape growth, ionome, amino acid and organic acid metabolism, and the expression of key S‐ and Fe‐homeostasis genes. Sulfur availability strongly shaped plant responses to iron availability, determining biomass allocation, ionomic patterns, and the expression of sulfate transporters, sulfur‐assimilatory enzymes, and iron homeostasis genes. Metabolomics highlighted citrate, O‐acetylserine, and methionine as root metabolites most consistently associated with combined Fe × S treatments. Correlation analysis linked these variables with markers of sulfate transport and assimilation, defining a reproducible interaction signature across biological layers. Sulfur deficiency, especially when combined with low iron, also increased free asparagine accumulation in vegetative tissues, indicating a strong reallocation in nitrogen metabolism under dual stress. Sulfur availability is a major modulator of iron‐responsive phenotypic, transcriptional, and metabolic traits in durum wheat and provides a systems‐level framework for future functional studies of Fe/S crosstalk.

Sustainable agriculture increasingly relies on biostimulants like protein hydrolysates (PHs) to enhance crop resilience. This study characterized and compared three plant-derived PHs (PH1, PH2, and PH3) from the Malvaceae, Brassicaceae, and Fabaceae families, respectively, under optimal (40 µM Fe³⁺-EDTA) and iron (Fe)-deficient (4 µM Fe³⁺-EDTA) conditions. Initial assays demonstrated that the PHs possessed significant antioxidant capacity and influenced biological activity: PH2 and PH3 promoted pollen germination, while PH1 exhibited a weaker stimulatory effect. In vivo experiments on tomato plants revealed that PH application effectively modulated root architecture and biomass accumulation. Moreover, PH2 and PH3 significantly mitigated Fe deficiency’s impact, by maintaining biomass and preventing chlorosis. Interestingly, while Fe deficiency typically triggers massive root Fe³⁺-chelate reductase activity, PH treatments, particularly PH2, significantly down-regulated this response. This suggests that PHs may improve internal Fe use efficiency or facilitate alternative uptake pathways. Overall, these findings establish a link between the intrinsic bioactive properties of PHs and their biostimulant action, highlighting their potential as innovative tools for improving nutrient use efficiency and crop resilience in sustainable farming systems.