Metallic allies in drought resilience: Unveiling the influence of silver and zinc oxide nanoparticles on enhancing tomato (Solanum lycopersicum) resistance through oxidative stress regulation

Abstract

The escalating influence of environmental changes has heightened the physiological challenges faced by plants, with drought stress increasingly recognized as a critical global issue significantly impeding affecting the crop productivity. This study investigates the effectiveness of metal nano particles such as zinc oxide nanoparticles (ZnO NPs) and silver nanoparticles (Ag NPs) in mitigating drought stress in Solanum lycopersicum. The foliar application of ZnO NPs (500 ppm) and/or Ag NPs (500 ppm), individually or in combination, significantly alleviated drought stress-induced. This mitigation was evidenced by enhanced antioxidant enzymes activity viz., catalase (64%), peroxidase (76%), superoxide dismutase (78%), chlorophyll content (31%) & photosynthesis (37%), and protein levels (15%). Furthermore, ZnO NPs and Ag NPs effectively mitigated oxidative stress and lipid peroxidation, as evidence by reduced accumulation of malondialdehyde (11%). Remarkably, the combined application of ZnO NPs and Ag NPs expedited the water-splitting capacity and facilitated electron exchange through redox reactions under drought stress. Consequently, these enhancements positively influenced the morpho-physiological characteristics such as height (28%), fresh weight (31%), dry weight (29%) and net photosynthetic rate (37%) of S. lycopersicum. These findings underscore the promising potential of metal NPs, such as ZnO NPs and Ag NPs, in mitigating drought stress, offering valuable insights for sustainable crop production amidst evolving environmental challenges.