Dose-Dependent Application of Silver Nanoparticles Modulates Growth, Physiochemicals, and Antioxidants in Chickpeas (<i>Cicer arietinum</i>) Exposed to Cadmium Stress

The present study was intended to investigate the effects of silver nanoparticles (Ag NPs) on chickpea plants grown in cadmium (Cd)-contaminated soil. Chickpea seeds sown in earthen pots (filled with soil) were subjected to Cd stress (100 μM) in the form of CdCl₂ (10 mL) 10 days after sowing (DAS). Exogenous applications with Ag NP concentrations 50, 100, and 200 μM were used to observe their effects on Cd-stressed plants. Growth, biochemical, and stress parameters were studied. Results showed that Ag NPs positively affected plant growth and ameliorated the toxic effects of Cd stress. Plant height, fresh weight, dry weight, total carotenoid content, rubisco activity, and net photosynthetic rate (<i>P</i> _N) were significantly decreased by Cd stress but enhanced by 28, 29, 31, 30, 33, and 35%, respectively, by foliar application of Ag NPs. Similarly, Ag NPs increased the activity of superoxide dismutase (61%), catalase (58%), and peroxidase (68%) and reduced the malondialdehyde (28%) and hydrogen peroxide (23%) in chickpea plants. Protein content was also increased by the application of Ag NPs (16%). Furthermore, the addition of Ag NPs decreased the plant Cd content. According to the current study, adding Ag NPs to plants under Cd stress improved their growth and photosynthesis by reducing Cd absorption and improving plant stress tolerance.