Efficiency of phosphate and potassium solubilizing bacteria on growth, yield, essential oil yield, and economics of davana ( Artemisia pallens Wall. ex. DC)

Sustainable agriculture depends on eco-friendly practices to ensure long-term productivity and environmental well-being. Phosphate and potash-solubilizing bacteria enhance nutrient availability, enrich soil health, and reduce chemical fertilizer dependency. To evaluate their effectiveness, field experiments were conducted in 2022–23 and 2023–24 at the CSIR-Central Institute of Medicinal and Aromatic Plants Research Center, Bengaluru. The study examined the impact of Bacillus megaterium and Frateuria aurantia on the agronomic performance and nutrient use efficiency of Artemisia pallens. The objective was to promote sustainable nutrient management while reducing chemical fertilizer reliance. The results of the field experiment state that, statistically superior growth parameters, herbage yield, and essential oil yield were recorded in treatment receiving 100% RDF+PSB+KSB followed by 75% RDF+PSB+KSB over the sole application, RDF, control treatments. Microbial consortia (PSB+KSB) with RDF are more significant in improving bacterial population than sole applications with RDF indicating synergism between different species of bacteria. Further application of 100% RDF combined with PSB and KSB resulted in the maximum AUE (Agronomic Use Efficiency) of 132.70% and a maximum microbial response of 35.25%, leading to a yield increase of 135.25% compared to other treatments. The maximum net returns (US$ 10.81) and the higher benefit-to-cost ratio of 3.95 were achieved with the application of 100% RDF+PSB+KSB. Overall, incorporating 75% RDF with both PSB and KSB together is highly beneficial to amplify the davana crop performance, bacterial population, and mineralization of nutrients in the soil and reduce the demand for chemical fertilizers thereby minimizing the environmental hazards.