Foliar humic acid and salicylic acid application stimulates physiological responses and antioxidant systems to improve maize yield under water limitations

Background Humic acid (HA) is an organic that naturally present in soil matter and improves nutrient availability the mechanisms involved plant growth development. Likewise, salicylic (SA) important hormone regulation of A pot experiment was carried out to determine effects individual or combined HA SA application on yield maize (Zea mays L.) under drought stress conditions. Two hybrids, namely, 30T60 (drought tolerant) 75S75 sensitive), were grown semi-controlled conditions foliar applied with (1 mM), (100 mg L−1) their combination (HA + SA). The plants exposed at tasseling stage (R1, 60 days after sowing) for 2 weeks, while control given normal irrigation. Results results showed applications significantly enhanced gas exchange characteristics (photosynthetic rate, transpiration stomatal conductance), antioxidant activity (catalase, guaiacol peroxidase, superoxide dismutase) water stressed plants. Foliar spray increased photosynthetic efficiency enzymatic antioxidants closely followed by ultimately improved net benefit cost ratio deficit Conclusion Our findings suggest spraying initiation reproductive a cost-effective strategy obtain high limited