Effect of Liquid Bio- fertilizers on Enhancing Plant Growth and Development of Mungbean (Vigna radiata L.)

Abstract

Liquid biofertiliser offers a sustainable alternative to chemical fertilisers for enhancing mungbean (Vigna radiata L.) growth and yield amid increasing global food demand. A field trial was conducted during 2024 and 2025 to determine the effects of seed treatments on early establishment, subsequent vegetative growth, phenology, and productivity. The study was arranged in a randomised block design with 11 treatments: an untreated control; seven individual liquid biofertiliser treatments (Rhizobium, PSB, KSB, VAM, Azospirillum, Pseudomonas, and EM); combined Rhizobium + PSB and Rhizobium + KSB treatments; and a chemical treatment (Thiram). The combined Rhizobium + phosphorus-solubilising bacteria (PSB) treatment recorded the highest values for field emergence (88.32%), plant stand (33.00 plants m⁻²), height (27.43 cm), chlorophyll index (51.80), canopy temperature depression (14.23°C), seed yield per plant (12.57 g), total seed yield (1052.20 kg ha⁻¹), straw yield (1653.89 kg ha⁻¹), and total biological yield (3023.34 kg ha⁻¹), while also recording the earliest flowering (36.67 days) and maturity (56.33 days). The synergistic effects of nitrogen fixation by Rhizobium and phosphorus solubilisation by PSB improved nutrient uptake, increased photosynthetic efficiency in mungbean plants, and supported source-sink relationships. All tested biofertilisers produced higher plant-growth parameters than the control, with the combined treatment showing the best overall performance. Rhizobium + PSB was identified as an effective and environmentally friendly option for increasing mungbean productivity, reducing reliance on chemical fertilisers, and maintaining soil quality and health.