Figure 1.

Colony forming units (CFU) in watered (blue bars) and drought (brown bars) sand where maize plants grew for 28 days at different conditions. Ctl—no addition of graphene oxide nanosheets, no bacterial inoculation; R—no addition of graphene oxide nanosheets, 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 three replicates + standard error. Different uppercase letters indicate significant differences (p < 0.05) among conditions in watered sand, different lowercase letters indicate significant differences among conditions under drought, and asterisks indicate significant differences between watered and drought for the same condition.