Comparative evaluation of formulated and Gracilaria edulis derived seaweed extract in enhancing growth, yield, quality and economics of Artemisia pallens Wall. ex. DC

Seaweed-based bio stimulants have emerged as promising, eco-friendly inputs for enhancing crop performance. However, their comparative efficacy on medicinal and aromatic plants like Artemisia pallens remains underexplored. Therefore, a field experiment was conducted at CSIR-Central Institute of Medicinal and Aromatic Plants, Bengaluru, India, during 2023–2024 to evaluate the effect of Gracilaria edulis seaweed extract (GLE) on the growth, yield, and essential oil quality of Artemisia pallens under semi-arid tropical conditions. The field experiment was laid out in a randomized complete block design with eight treatments, including five concentrations of GLE ranging from 2.5 % to 15 % along with the recommended dose of fertilizers (RDF), a commercial seaweed formulation (Sagarika) at 0.25 % (SKG) with RDF and Sole RDF as a control treatment. GLE was applied as a foliar spray at 30-day intervals from 30 days after transplanting. Application of 10 % GLE significantly enhanced the growth and yield traits of A. pallens compared to the control, with effects comparable to those of 0.25 % SKG. Notably, 10 % GLE resulted in higher herbage yield (17.78 t ha⁻¹) and essential oil yield (39.00 kg ha⁻¹) than the control (13.32 t ha⁻¹ and 27.27 kg ha⁻¹), and was statistically similar to the 0.25 % SKG treatment. Highest agronomic nutrient efficiency and economic return, with a benefit-cost ratio (B:C ratio) of 3.38 was also recorded in 10 % GLE application. The essential oil recovery remained unaffected by GLE application, ranging from 0.19 % to 0.23 %. Furthermore, the GLE application exhibited marginal increases in the concentrations of cis-Davanone, davana ether (Isomer-1), and bicyclogermacrene. However, the influence of seaweed extract on the essential oil composition was not statistically significant. In conclusion, the application of 10 % GLE offers a sustainable and effective strategy to enhance the growth, yield, and profitability of A. pallens without significantly altering essential oil composition.