Fig 2. Effects of ZnO NPs and MWCNTs, alone or in combination, on chlorophyll content of Arabidopsis seedlings at 10 DAG.

(a) Relative total chlorophyll content. (b) Relative chlorophyll-a content. (c) Relative chlorophyll-b content. ½ MS medium without NPs was used as control. Data are the means ± standard errors of three replicates. Different letters indicate a significant difference between treatments (P < 0.05, Duncan test).