Enhancing maize drought resilience through combined fertilizer fertilization: a study of two Iranian regions | Enhancing maize drought resilience through integrated fertilizer management: a study of two Iranian regions

English. This study examined the combined effects of drought stress and combined fertilizer on maize yield and physiological features in Iran's Bam and Fahraj regions. The experiment used a split-plot design with randomized blocks in three replications. Irrigation treatments were applied at three levels: control (-3 bar), moderate stress (-7 bar), and severe stress (-11 bar). Fertilizer treatments included control (no fertilizer), chemical fertilizer (300 kg N + 150 kg triple super phosphate ha⁻¹), biofertilizer (phosphate Barvar-2 and Nitroxin 100%), vermicompost, and combined fertilizer treatment (50% chemical fertilizer + 100% biofertilizer).  The results showed that combined fertilizer application under optimal irrigation conditions had the highest impact. Grain yield in Bam region increased from 5,640.6 kg/ha in the control condition to 12,341.2 kg/ha in the combined fertilizer treatment, and in Fahraj region from 4,140 kg/ha to 10,840.6 kg/ha. The harvest index under non-stress and combined fertilizer treatment conditions showed the highest levels in Bam (45.94%) and Fahraj (44.21%). With increasing drought stress intensity, the harvest index decreased, reaching 27.61% in Bam under severe stress. The overall conclusion indicates that combined fertilizer management is an effective strategy for increasing drought tolerance and improving corn performance in arid regions. The combination of chemical and biological fertilizers was able to reduce the negative effects of drought stress and improve crop production efficiency.

Portuguese. This study was developed in order to examinate the combined effects of drought stress and integrated fertilizer management on maize yield and physiological characteristics in Iran's Bam and Fahraj regions. The experiment used a split-plot design with randomized complete blocks in three replications. Drought stress treatments were applied at three levels: no stress (-0.3 MPa), mild drought stress (-0.7 MPa), and severe drought stress (-1.1 MPa). Six fertilizer treatments were evaluated: no fertilizer, chemical fertilizer (300 kg N ha⁻¹ + 150 kg P₂O₅ ha⁻¹), phosphate biofertilizer, nitrogen biofertilizer, vermicompost (5 t ha⁻¹), and integrated fertilizer management, combining 50% chemical fertilizer with both biofertilizers and vermicompost. Integrated fertilizer management under optimal irrigation conditions had the highest impact on crop performance. Grain yield in Bam region increased from 5640.6 kg ha⁻¹ under no stress conditions to 12341.2 kg ha⁻¹ with integrated fertilizer treatment; and in Fahraj region from 4140 kg ha⁻¹ to 10840.6 kg ha⁻¹. The harvest index under no stress and integrated fertilizer treatment conditions reached the highest levels in Bam (45.94%) and Fahraj (44.21%). With increasing drought stress intensity, the harvest index decreased significantly, reaching 27.61% in Bam under severe drought stress conditions. Therefore, integrated fertilizer management is an effective strategy for enhancing drought tolerance and improving maize performance in arid regions. The combination of chemical and biological fertilizers successfully mitigated the negative effects of drought stress and improved crop production efficiency.