Nano-priming of pea (Pisum sativum L.) seeds with CuO nanoparticles: Synthesis, stabilization, modeling, characterization, and comprehensive effect on germination and seedling parameters

CuO nanoparticles (NPs) can boost germination and seedling development of agricultural crops. However, it is either extremely contradictory or difficult to compare in terms of doses, dimension, nature, stability of CuO NPs and activity of stabilizing agents. This study focused on synthesis and characterization of CuO NPs stabilized with various polysaccharides. CuO NPs-hyaluronic acid complex was the most energetically favorable and stable. 0.1 mg/L CuO NPs led to the highest germination energy, germinability, and root and seedling lengths, while higher concentrations had growth suppression or inhibition effect on seedling and root development. Histological studies showed noticeable structural changes caused by intense Cu translocation and accumulation: Cu content reached 56.01 mu g/L at 100 mg/L CuO NPs, which affected antioxidant activity and photosynthesis indicators. Interestingly, the growth-stimulating effect of CuO NPs stabilized with hyaluronic acid at a concentration of 0.1 mg/L, contrasted with a pronounced toxic effect observed at 100 mg/L.