Relative transcript abundances of Les.564.1.S1- heat shock protein 90 in leaves (A), Les.49.1.S1- TDR3 protein in roots (B), and LeAqp2 protein in roots (C) of tomato seedlings exposed to AC, CNTs in concentrations 50, 100, and 200 μg/mL), and seedlings not exposed to carbon materials (CNT 0). Expression of genes was analyzed by real-time RT-qPCR. Results are shown as the average of three independent biological replicates. Relative expression levels were normalized to an internal standard (actin transcript) for each treatment. Bars represent standard error (SE) of means.