Effect of copper oxide and zinc oxide nanoparticles on photosynthesis and physiology of Raphanus sativus L. under salinity stress

• Published in: Plant physiology and biochemistry 2024-01, Vol.206, p.108281-108281, Article 108281
• Main Authors: Mahawar, Lovely, Živčák, Marek, Barboricova, Maria, Kovár, Marek, Filaček, Andrej, Ferencova, Jana, Vysoká, Dominika Mlynáriková, Brestič, Marián
• Format: Article
• Language: English
• Subjects: Antioxidants; Chlorophyll fluorescence; Foliar spray; Metal oxide nanoparticles; NaCl stress; radish
• ISSN: 0981-9428; 1873-2690; 1873-2690
• DOI: 10.1016/j.plaphy.2023.108281

The study evaluates the impact of two metal oxide nanoparticles: copper oxide (CuO) and zinc oxide (ZnO) on the growth and physiology of Raphanus sativus L. (radish) under salinity stress. Fifteen days old seedlings of R. sativus were subjected to different concentrations of salt stress (0 mM, 150 mM, and 300 mM NaCl) alone and in interaction with 100 mgL−1 metal oxide nanoparticle treatments (CuO and ZnO NPs via foliar spray) for 15 days. The results confirmed the severe effects of salinity stress on the growth and physiology of radish plants by decreasing nutrient uptake, leaf area, and photosystems photochemistry and by increasing proline accumulation, anthocyanin, flavonoids content, and antioxidant enzyme activities which is directly linked to increased oxidative stress. The foliar application of CuO and ZnO NPs alleviated the adverse effects of salt stress on radish plants, as indicated by improving these attributes. Foliar spray of ZnO NPs was found efficient in improving the leaf area, photosynthetic electron transport rate, the PSII quantum yield, proton conductance and mineral content in radish plants under NaCl stress. Besides, ZnO NPs decreased the NaCl-induced oxidative stress by declining proline, anthocyanin, and flavonoids contents and enzymatic activities such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (GOPX). Thus, our study revealed that ZnO NPs are more effective and have beneficial effects over CuO NPs in promoting growth and reducing the adverse effects of NaCl stress in radish plants. •Salinity stress adversely affects the growth and physiology of radish.•Salinity stress decreases the nutrient uptake, photosystems photochemistry, leaf area and increases oxidative stress in radish plants.•Foliar application of copper oxide (CuO) and zinc oxide (ZnO) nanoparticles reduces the negative effects of salt stress.•ZnO nanoparticles are more effective in improving photosynthesis and growth, and declining oxidative stress in salt stressed plants.