Bio-fertilizers ameliorate drought tolerance and physio-biochemical attributes of Moringa oleifera plants under different irrigation scheduling

Abstract

Increased drought stress is anticipated to impact crop productivity adversely, mainly in Africa and Southeast Asia. Drought-tolerant plant growth-promoting rhizobacteria (PGPR) have emerged as a ray of hope as an effective bio-enhancer and sustainable strategy for agriculture under water-deficit and recovery conditions to reduce reliance on chemical fertilizers and improve soil fertility. Keeping this in view, a field experiment was conducted to check the effectiveness of commercial bio-fertilizers Phosphorine, Microbine, Potassiumag individually, or in combination with organic fertilizer (compost), and natural mineral rock (rock phosphate), as a substituent of chemical fertilizer. Two drip irrigation schedules W1 (100%) and W2 (60% of field capacity FC) were applied to evaluate growth and biochemical traits of Moringa oleifera under varying biofertilizer inputs. The highest values of plant growth under W1 were recorded in the plants amended with BioMix1 (Microbine mixed with rock phosphate and compost), plant height (150 cm), number of branch plant−1 (19), plant dry weight (203 g). On the other hand, individual application of Potassiumag (Bio3) showed the highest of plant growth under W2 water scheduling, with plant height (130 cm), number of branch plant−1 (17), plant dry weight (137 g). The present work evaluated a broad range of both non-enzymatic antioxidant components including phenolics, proline, ascorbate and carotenoids, in addition to peroxidase (POD), ascorbate peroxidase (APX) and catalase (CAT) enzymes. Microbine with compost and rock phosphate improved Moringa oleifera yield and quality at 100% FC, while Potassiumag followed by Phosphorine sustained growth under drought 60%FC.