Cadmium (Cd) contamination in soil poses a significant environmental threat, reducing crop yields and compromising food safety. This study investigates the potential of selenium nanoparticles (Se-NPs) synthesized using wheat extract to mitigate Cd toxicity, reduce Cd uptake and mobility, and recover grain nutrient composition in wheat (Triticum aestivum L.). A pot experiment was conducted following a completely randomized design (CRD) with three replications. Treatments included control, four Se-NPs concentrations (10, 25, 50, and 100 ppm), four Cd stress levels (25, 50, 75, and 100 ppm), and their combined interactions. Various physiological, biochemical, and agronomic parameters were analyzed to assess the mitigation potential of Se-NPs against Cd toxicity in wheat. Se-NPs (36.77 nm) were characterized using FTIR, confirming functional groups for stabilization, XRD verifying crystallinity and size via the Scherrer Equation, SEM revealing spherical morphology, and EDX confirming selenium as the predominant element with minor trace elements. Under 50 ppm Cd stress, Se-NPs at 25 ppm reduced days to anthesis by 8.16 % and mitigated a 45.13 % decrease in plant height. Grain yield, which declined by 90.86 % under Cd stress, was restored by 90.86 % with 10 ppm Se-NPs. Additionally, Se-NPs improved thousand kernel weight by 32.71 %, counteracting a 25.92 % reduction due to Cd stress. Antioxidant enzyme activities, including SOD and CAT, increased by up to 333.79 % in roots with Se-NP treatment, while oxidative stress markers decreased by 28 %. Moreover, Se-NPs effectively mitigated Cd uptake and reduced its mobility within the plant. Grain protein content improved by 16.89 %, and carbohydrate levels were maintained at 4.61 % despite Cd exposure. These findings indicate that Se-NPs enhance crop resilience, supporting sustainable food production in Cd-contaminated environments.

Drought is a serious environmental challenge that reduces the productivity of valuable crops, including wheat. Brassinosteroids (BRs) is a group of phytohormones that have been used to enhance wheat drought tolerance. Wheat cultivars with different adaptation strategies could have their own specific drought tolerance mechanisms, and could react differently to treatment with growth regulators. In this work, the effect of seed pretreatment with 0.4 mu M 24-epibrassinolide (EBR) was investigated in two wheat (Triticum aestivum L.) cultivars contrasting in drought behavior, tolerant Ekada 70 (cv. E70) and sensitive Zauralskaya Zhemchuzhina (cv. ZZh), in early ontogenesis under dehydration (PEG-6000) or soil drought conditions. EBR pretreatment mitigated the stress-induced inhibition of seedling emergence and growth, as well as membrane damage in cv.E70 but not in ZZh. An enzyme-linked immunosorbent assay (ELISA) revealed substantial changes in hormonal balance associated with ABA accumulation and a drop in the levels of IAA and cytokinins (CKs) in drought-subjected seedlings of both cultivars, especially ZZh. EBR-pretreatment reduced drought-induced hormone imbalance in cv. E70, while it did not have the same effect on ZZh. EBR-induced changes in the content of wheat germ agglutinin (WGA) belonging to the protective proteins in E70 seedlings suggest its contribution to EBR-dependent adaptive responses. The absence of a detectable protective effect of EBR on the ZZh cultivar may be associated with its insensitivity to pre-sowing EBR treatment.