Physiological and biochemical responses of potato (Solanum tuberosum) to silver nanoparticles and silver nitrate treatments under in vitro conditions

Abstract

A study was carried out to investigate the effects of nano-silver particles (AgNPs) or silver nitrate (AgNO3) supplementation to in vitro culture of potato plant. Results indicated that 2 mg l−1 of AgNPs or AgNO3 treatment resulted in improvement in some growth parameters such as dry weight, root length and leaf area. However, shoot length was significantly reduced. Total chlorophyll and carotenoids in treated explants were significantly increased. Anthocyanin content increased only in AgNO3 treatments in a dose-dependent manner, while AgNPs treatments at 2 mg l−1 and higher levels increased and decreased, respectively. Compared with untreated explants, treated explants exhibited no alteration in proline content at 2 mg l−1 but increased at 10 and 20 mg l−1 treatments. Flavonoids content increased only in explants treated with 2 mg l−1 of AgNPs. Total phenolics were significantly increased under all treatments compared with untreated explants. AgNPs and AgNO3 treatments showed an increase in H2O2 content and lipid peroxidation under 10 and 20 mg l−1. Lipid peroxidation and H2O2 contents in explants treated with AgNPs were remarkably higher than in case of AgNO3. Results showed that AgNPs treatment enhanced growth of potato explants, which could possibly be due to inhibitory effects of silver ion on ethylene perception. Furthermore, AgNPs exhibited stronger toxicity than AgNO3 at 10 and 20 mg l−1 concentrations.