EICHHORNIA CRASSIPES-BASED HYDROPONIC GROWTH MEDIUM: A SUSTAINABLE APPROACH TO PLANT CULTIVATION AND RESOURCE VALORIZATION

The increasing demand for sustainable food production has intensified the search for biodegradable and cost effective alternatives to conventional hydroponic growing substrates. The present study investigated the potential of Eichhornia crassipes (water hyacinth) biomass incorporated with carboxymethyl cellulose (CMC) as a biodegradable hydrogel substrate for the cultivation of Vigna radiata L. An aqueous extraction method was employed to recover polymer from E. crassipes, yielding approximately 10% polymer with a pH of 6.0. The extracted polymer was incorporated with CMC to develop an Eichhornia-CMC hydrogel, and its performance was compared with CMC hydrogel and conventional soil. Seed germination, seedling vigour, shoot and root growth, leaf development, chlorophyll content, water retention, biochemical composition, mineral accumulation, and endogenous auxin content were evaluated. The Eichhornia-CMC hydrogel promoted rapid seed germination and superior seedling development, with a Seed Vigour Index of 382 compared with 287 and 370 in CMC hydrogel and soil, respectively. Plants cultivated on the Eichhornia-based hydrogel exhibited higher shoot and root lengths, leaf area (4.0 cm²), chlorophyll content (0.872 mg g⁻¹), ash content (3.65 g), and water content (53.33%). Enhanced carbohydrate (0.045 mg g⁻¹), protein (0.050 mg g⁻¹), and lipid (0.003 mg g⁻¹) contents were also recorded. The extracted polymer contained detectable endogenous auxin ranging from 4.2 to 4.6 µg mL⁻¹, suggesting additional plant growth-promoting potential. Overall, the findings demonstrate that Eichhornia-CMC hydrogel can serve as a promising biodegradable hydroponic substrate while simultaneously valorizing invasive aquatic biomass and supporting circular bioeconomy approaches in sustainable agriculture.