Proteomic, Biochemical, and Morphological Analyses of the Effect of Silver Nanoparticles Mixed with Organic and Inorganic Chemicals on Wheat Growth

Wheat is vulnerable to numerous diseases; on the other hand, silver nanoparticles (AgNPs) exhibit a sterilizing action. To understand the combined effects of AgNPs with nicotinate and potassium nitrate (KNO(3)) for plant growth and sterilization, a gel- and label-free proteomics was performed. Root weight was promoted by the treatment of AgNPs mixed with nicotinate and KNO(3). From a total of 5557 detected proteins, 90 proteins were changed by the mixture of AgNPs, nicotinate, and KNO(3); among them, 25 and 65 proteins increased and decreased, respectively. The changed proteins were mainly associated with redox and biotic stress in the functional categorization. By immunoblot analysis, the abundance of glutathione reductase/peroxiredoxin and pathogen-related protein three significantly decreased with the mixture. Furthermore, from the changed proteins, the abundance of starch synthase and lipoxygenase significantly increased and decreased, respectively. Through biochemical analysis, the starch contents increased with the mixture. The application of esculetin, which is a lipoxygenase inhibitor, increased the weight and length of the root. These results suggest that the AgNPs mixed with nicotinate and KNO(3) cause positive effects on wheat seedlings by regulating pathogen-related protein and reactive-oxygen species scavenging. Furthermore, increasing starch and decreasing lipoxygenase might improve wheat growth.