Author(s): Ethan J Caldwell

Abstract: Plant-based biostimulants are increasingly promoted as tools to enhance crop performance and nutrient-use efficiency while reducing reliance on synthetic fertilizers. A field experiment was conducted for two rabi seasons to assess the effects of selected plant-derived biostimulants on growth and yield dynamics of potato (Solanum tuberosum L., cv. Kufri Chipsona-3). Treatments comprised: T? - 100% recommended fertilizer dose (RDF, control); T? - 100% RDF + seaweed-based biostimulant; T? - 100% RDF + plant-derived protein hydrolysate; T? - 100% RDF + complex plant-based biostimulant; and T? - 75% RDF + integrated biostimulant package (seaweed extract + protein hydrolysate + complex botanical formulation). Biostimulants were applied as a seed-tuber dip and foliar sprays at 30 and 45 days after planting (DAP) in a randomized complete block design with three replications. Biostimulant treatments significantly increased leaf area index (LAI), crop growth rate (CGR), and net assimilation rate (NAR) during the main bulking phase compared with RDF alone (P ? 0.05). The highest LAI at 60 DAP occurred in T? (3.92) and T? (3.78) versus T? (3.21). Total and marketable tuber yields increased by 15-20% under T? and T?, mainly through higher tuber number per plant and increased mean tuber weight. Tuber dry matter, nitrogen uptake, and agronomic nitrogen-use efficiency (AE N) improved, with the greatest AE N observed under T?, indicating that 25% mineral NPK reduction can be achieved without yield penalty when coupled with an integrated biostimulant package. Economic returns increased under all biostimulant treatments, with the highest B:C ratio under T?. Overall, plant-based biostimulants are effective components of integrated nutrient management for potato, enhancing productivity and profitability while lowering dependence on synthetic fertilizers.

DOI: 10.22271/flora.2025.v13.i5b.1039