Silver nanoparticles with different concentrations and particle sizes affect the functional traits of wheat

Abstract

The response of functional traits of plants to external environment can influence their competitive ability because these functional traits are required for the acquisition of resources. The overuse of silver nanoparticles (AgNPs) has gained attention due to their environmental toxicity. This study aimed to examine the effects of AgNPs with different concentrations and particle sizes on functional traits of wheat. It was observed that AgNPs significantly reduced the plant height and so decrease its competitive ability. Ag ions decreased leaf chlorophyll and nitrogen content and specific leaf area more than AgNPs, but the opposite was true for leaf length, single leaf fresh mass, and shoot fresh mass. Hence, the toxicity of AgNPs may be higher than that of Ag ions in some cases. In this study, leaf chlorophyll and nitrogen content decreased with increasing concentration of AgNPs (with size 30 nm). The AgNPs with smaller particle size exerted higher toxicity on leaf chlorophyll and N content than those with larger particle size at the same concentration. However, AgNPs with larger particle size reduced more aboveground fresh mass than those with smaller particle size at the same concentration.