Figure 2.

Root (a) and shoot (b) growth relative to control (condition Ctl) of maize plants watered (blue bars) or drought (brown bars) grown at different conditions. Ctl—no addition of graphene oxide nanosheets, no bacterial inoculation; R—no graphene oxide nanosheets addition, inoculation with Rhizobium strain E20-8; GO—addition of graphene oxide nanosheets, no bacterial inoculation; R + GO—addition of graphene oxide nanosheets and inoculation with Rhizobium strain E20-8. Values are means of at least six replicates ± standard error. Different uppercase letters indicate significant differences (p < 0.05) among conditions in watered plants, different lowercase letters indicate significant differences among conditions in drought plants, and asterisks indicate significant differences between drought and watered plants for the same condition.