Effect of Silver Nanoparticles on Growth of Wheat Under Heat Stress

Abstract

The present study was conducted to investigate the effect of AgNPs in the regulation of growth of wheat under heat stress. Plant extract of Moringa oleifera was used for AgNPs synthesis followed by characterization through UV–Vis spectroscopy, XRD, SEM and AFM. Different concentrations of AgNPs (25, 50, 75 and 100 mg/l) were applied to wheat plants at trifoliate stage. Heat stress was applied in range of 35–40 °C for 3 h/day for about 3 days. Exposure of heat stress alone reduced plant fresh mass (1.2%), dry mass (0.16%), root length (2.5%), shoot length (6.2%), root number (1.8%), leaf area (12.1%), leaf fresh mass (0.02%), leaf dry mass (0.01%) and leaf number (2%), respectively. However, application of AgNPs protects wheat plants against heat stress and improve plant root length (5 and 5.4%), shoot length (22.2 and 26.1%), root number (6.6 and 7.5%), plant fresh weight (1.3 and 2%) and plant dry weight (0.36 and 0.60%) in 50 and 75 mg/l AgNPs, respectively, compared to control. Similarly, remarkable increase in leaf area (18.3 and 33.8%), leaf number (4 and 4.8%), leaf fresh weight (0.09 and 0.15%) and leaf dry weight (0.06 and 0.18%) has been noticed in 50 and 75 mg/l AgNPs over respective value of control under heat stress. Although, AgNPs increase morphological growth at all tested combinations, but significant results were observed at 50 and 75 mg/l AgNPs under heat stress. In conclusion, application of AgNPs may protect wheat plants against heat stress by improving morphological growth.