Fig. 1

Effect of biochar and sodium hydrosulfide (NaHS) on maize growth and biomass under drought stress. Treatments: T0 = control, T1 = 3% biochar mixed with pot soil, T2 = 0.05 mmol L⁻¹ NaHS, T3 = 0.1 mmol L⁻¹ NaHS, T4 = biochar + 0.05 mmol L⁻¹ NaHS, T5 = biochar + 0.1 mmol L⁻¹ NaHS. Stress levels: MDS = moderate drought stress, SDS = severe drought stress. Traits: plant height, ear diameter, and ear length.