Phytotoxic effect of silver nanoparticles in Triticum aestivum: Improper regulation of photosystem I activity as the reason for oxidative damage in the chloroplast

Abstract

Silver nanoparticles (AgNPs) are used in several industries and their continuous release into environment can damage the ecosystem. Our study observed the impact of two concentrations of AgNPs (1 and 5 mM) on wheat seedlings. In this study, the treatment of AgNPs was found to have a significant impact on growth parameters, such as root and shoot length of wheat seedlings, in addition to that biochemical parameters, such as activity of catalase, glutathione, flavonoid, and chlorophyll concentrations, were also affected. AgNPs apparently suppressed the photosynthetic activity of the seedlings, with a clear destruction of photosystems at 5 mM concentration. The result also indicated an improper regulation of PSI electron transport, resulting in a damage to chloroplast structure, including photosystem itself. Our study presents a mechanism of the AgNPs action of on photosynthetic processes in plants.

Keywords

• antioxidants; chlorophyll fluorescence; jip test.