Plant-Microbe Interactions and Their Role in Sustainable Agriculture

https://doi.org/10.5281/zenodo.20625415

Abstract

Plant growth-promoting microbes (PGPMs) play a pivotal role in enhancing crop productivity, nutrient uptake, disease resistance, and soil health, offering sustainable alternatives to chemical fertilizers and pesticides. This study evaluated the effects of individual microbial inoculants Rhizobium sp., Azotobacter sp., Pseudomonas fluorescens, and arbuscular mycorrhizal fungi (AMF) and a consortium combining all strains on crop growth, yield, nutrient acquisition, disease suppression, soil fertility, and economic returns under controlled greenhouse conditions. Results demonstrated that the consortium significantly increased plant height (58.7 cm), shoot biomass (20.3 g plant⁻¹), root biomass (7.6 g plant⁻¹), total biomass (27.9 g plant⁻¹), grain yield (72.6 g plant⁻¹), and nutrient content (N 30.6 mg g⁻¹; P 6.2 mg g⁻¹), while reducing disease incidence (15.6%) and severity (1.1). Soil health indicators, including organic carbon (2.0%), enzyme activity (26.5 µmol g⁻¹ h⁻¹), microbial biomass (275 mg g⁻¹), and diversity index (3.0), were markedly improved. Economic analysis revealed the highest net return ($1750/ha) and benefit-cost ratio (1.45) for the consortium. These findings highlight the synergistic potential of multi-strain microbial inoculants in promoting sustainable crop production, improving soil quality, mitigating disease, and enhancing economic profitability.