Zinc oxide nano-priming fortifies Triticum aestivum L. against salt stress through physio-morphological, biochemical and transcriptomic responses
Ateeq, M (Ateeq, Muhammad) [1] , [2] ; Ashraf, MA (Ashraf, Muhammad Azeem) [1] , [2] ; Dong, QF (Dong, Qingfeng) [1] , [2] ; Ren, H (Ren, Hao) [1] , [2] ; Yasir, TA (Yasir, Tauqeer Ahmad) [3] ; Huang, LZ (Huang, Linzhou) [1] , [2] ; Chen, L (Chen, Liang) [1] , [2] ; Hu, YG (Hu, Yin-Gang) [1] , [2]
DOI:10.1007/s11104-026-08451-5
Abstract
Background and AimsPlants frequently encounter salinity stress throughout their life cycle. This study comprehensively elucidates the role of zinc oxide nanoparticles (ZnO-NPs) priming in regulating long-term salinity tolerance in wheat by modulating physio-biochemical and transcriptional attributes, leading to improved plant biomass.MethodsWheat seeds were primed with ZnO-NPs (0, 50, 100, 150 and 200 mg/l) and grown in control (0 mM) and salt stress (150 mM).ResultsFindings demonstrated that priming with 100 mg/L of nano-sized ZnO maximally allowed it to easily penetrate and translocate throughout the plant tissues and cellular compartments, and reduced sodium (Na+) uptake by 24% in shoot and 21% in root under salt stress. Physiologically, ZnO-NPs priming alleviated salinity damage by improving photosynthesis-related traits such as stomatal conductance (Gs), net photosynthetic rate (Pn), intracellular CO2 concentration (Ci), transpiration rate (E), and maximum photochemical efficiency of photosystem II (Fv/Fm), resulting in enhanced plant growth traits and glutathione content, while reduction in electrolyte leakage (EL) and reactive oxygen species (ROS) production. It also promoted potassium (K+) uptake, stomatal conductance, photosynthetic efficiency, and anatomical structure under saline condition. Additionally, ZnO-NPs upregulated the expression of ZIP gene family and simultaneously modulated the expression of salinity-responsive genes, including SOS, NHX, RN and HKT, which results in the activation of AsA-GSH pathway genes and photosynthesis-related genes, including Psb27, Psb28, PsbQ, PsbP, Lhca5 and Lhca6.ConclusionZnO nano-priming advances our understanding of zinc translocation, accumulation and usage in wheat, and emerged as a most effective strategy for enhancing salt stress tolerance in cereal crops.