Effects of PEG-simulated drought stress and selenite treatment on mineral nutrient homeostasis in wheat roots and shoots

Drought stress severely impairs seed germination and early seedling establishment, and disrupts the uptake and distribution of essential mineral nutrients in plants. This study investigated the effects of polyethylene glycol (PEG)-simulated drought and Na2SeO3 application on the accumulation and redistribution of phosphorus (P), potassium (K), calcium (Ca), sulphur (S), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn) in wheat roots and shoots. Under PEG-simulated drought, increasing PEG concentrations resulted in a progressive decline in nutrient concentrations in both roots and shoots, with significant reductions in K, Ca, S, Zn, and Mn in roots, and K, Ca, Mg, and Mn in shoots. However, Na₂SeO₃ application mitigated these adverse effects by enhancing nutrient redistribution during early seedling growth. Specifically, under 15% PEG-simulated drought stress, Na₂SeO₃ treatments significantly increased shoot K, Mg, Fe, and Cu concentrations, highlighting selenium’s role in facilitating the translocation of these key elements. These results demonstrate that Na₂SeO₃ effectively mitigates drought-related nutrient imbalances and promotes ion remobilisation from germinating seeds to developing roots and shoots under water-deficient conditions.