Moringa dried leaf extract as bio-foliar fertilizer for revitalizing performance and nutritional status of soybean

Naturally occurring plant based biostimulants can be used to improve crop productivity and quality as an eco-friendly approach. Moringa oleifera, known as the miracle tree, is a rich source of essential nutrients and beneficial compounds that can act as a potent growth enhancer. Its leaves are nutrient dense that contain rich blends of essential vitamins (A, C, K, and E), riboflavin, iron (Fe) and diverse range of phenolics. The current work (pot experiment) aimed to appraise whether moringa dried leaf extract (MDLE) could improve growth, physiology, seed nutritional and quality attributes of soybean (Glycine max). The designed study followed a completely randomized design with factorial arrangement having four replications examining various MDLE concentrations [water spray as control, 0.5%, 1.0%, and 1.5% (w/v)] and growth stages [vegetative (V4, four leaf stage) and reproductive (R1: onset of flowering)] of soybean. The results revealed that foliar application of 1.5% MDLE during the reproductive stage of soybean showcased statistically significant improvements in growth, yield and seed nutritional attributes. Notably, seedling growth attributes, photosynthetic pigments, leaf area, gas exchange parameters, yield attributes, seed nutritional and quality attributes were significantly boosted. The observed improvements in soybean growth, physiology, and yield can be attributed to the bioactive compounds in MDLE. Cytokinins promote cell division and delay senescence, antioxidants mitigate oxidative stress, and essential minerals enhance nutrient uptake and enzymatic activity. These interactions collectively enhance photosynthesis, biomass accumulation, and seed development, leading to improved crop performance. Overall, increments in seedling growth metrics (22%), leaf area (16.12%), carotenoids (photosynthetic pigment) (8.33%), gas exchange attributes (18%), yield components (37%) and seed nutritional attributes (18%) were observed with 1.5% MDLE application during the reproductive stage. This underscores the potential of MDLE foliar application during reproductive stage in improving soybean growth, quality and seed nutritional contents. Compared to other biostimulants, MDLE offers a cost-effective and environmentally friendly alternative with multiple benefits, including enhanced nutrient efficiency, reduced dependency on synthetic fertilizers, and potential resilience against abiotic stress. Its scalability in large-scale agriculture is promising due to its easy preparation, affordability, and compatibility with existing farming practices, making it an attractive option for sustainable intensification. Future research should uncover how MDLE works and its potential in stressful environments in field as well as in controlled conditions, advancing sustainable agriculture.