Vol. 7, Issue 5, Part A (2025)

Agrochemicals including synthetic herbicides are being applied intensively by farmers in Benue State. The aim of this study was to investigate the biosorption potentials of duckweed (Lemma minor) and water lettuce (Pistia stratoites) in the treatment of water contaminated with herbicide. The complete randomized design (CRD) was used. Experimental water samples containing test plants were analyzed for heavy metals (Pb, Cr, Mn), nutrient enrichment (N, P, K) and physicochemical parameters while test plants were evaluated for growth features. Indices of aquatic phytoremediation were computed including HPI (heavy metal pollution indices), PRI (phytoremediation index) and PE (phytoremediation efficiency). Data analysis was done using multivariate analysis tool while mean separation of ANOVA was done using Fisher LSD at p≤005. Plant-herbicide interaction showed that only duckweed had a reducing effect where Cr (0.01 ppm) and Pb (0.009 ppm) concentrations were very low in water. Hence, duckweed treated water had HPI <1, with higher PE in Pb (90%) and Cr (85.7%) than water lettuce, but the two test plants had high PE (99%) for Mn. Levels of nutrients (N, P, K) were reduced in duckweed treatment. Test plants demonstrated potentials in improving physicochemical parameters of herbicide contaminated water except the pH. Only water lettuce showed an increase in stem diameter and leaf sizes while duckweed recorded a decrease in all growth parameters. Duckweed is recommended for herbicide polluted water. The two adaptable test plants demonstrated capacity to improve physicochemical properties of water contaminated with herbicide.