Bio-fertilizers as a sustainable alternative to chemical fertilizers: an assessment of growth, nutrient uptake and soil health in fenugreek cultivation

Abstract

Fenugreek (Trigonella foenum-graecum L.) is cultivated for its edible leaves and seeds, making reliable growth and nutrient supply important to both vegetable and seed production. Bio-fertilizers containing beneficial microorganisms have been proposed as a means of improving nutrient availability while reducing dependence on chemical fertilizers. This article evaluates that proposition through three connected outcomes: fenugreek growth, nutrient uptake, and soil health. Rhizobial inoculants can support biological nitrogen fixation in compatible root nodules, while phosphate-solubilizing bacteria can mobilize some poorly available phosphorus. Other plant-growth-promoting bacteria may influence root development and nutrient acquisition. Fenugreek field studies in Rajasthan and Gujarat report benefits from selected microbial treatments, including combined Rhizobium and phosphate-solubilizing bacterial inoculation. They also reveal variation: one Jobner study recorded its highest seed yield and returns from inorganic nitrogen alone, while other studies favoured integrated organic, microbial, and mineral nutrient treatments. Bio-fertilizers therefore have potential as part of a sustainable nutrient-management strategy, but their capacity to replace a particular fertilizer input cannot be assumed. Evidence of soil health requires measurements extending beyond crop yield, including soil organic carbon, available nutrients, microbial activity, and the performance of subsequent crops. The article concludes that locally adapted inoculants, sound organic-matter management, soil testing, and replicated field evaluation offer a more defensible route to reducing unnecessary chemical inputs than a universal claim of complete replacement.