Evaluating the Larvicidal Efficiency of Selected Botanical Plant Extracts against Dengue Vector Aedes sp.

Growing numbers of mosquito-borne diseases worldwide, especially dengue fever, demand sustainable and environmentally friendly control measures. This study compared the larvicidal effects of five medicinal plant extracts-Nicotiana tabacum (Tobacco), Acorus calamus (Sweet flag), Pongamia pinnata (Pungam), Calotropis sp., and Aristolochia bracteolata (Worm killer)—against Aedes sp. larvae. Methanolic extracts were tested at concentrations ranging from 25 to 500 ppm, and larval mortality was recorded after 24 h of exposure. Acorus calamus exhibited the highest larvicidal efficacy, with 98.00 ± 2.45% mortality at 500 ppm and the lowest lethal concentration values (LC₅₀ = 58.07 ± 0.80 ppm; LC₉₀ = 557.82 ± 0.75 ppm; LC₉₉ = 1103.22 ± 0.75 ppm). Calotropis sp. showed moderate activity with an LC₅₀ of 97.27 ± 0.75 ppm. One-way ANOVA revealed significant differences in larval mortality among plant extracts (p < 0.05), and Tukey post hoc analysis indicated that Acorus calamus differed significantly from Pongamia pinnata and Aristolochia bracteolata (p < 0.05). Regression analysis showed a significant dose–response relationship for all extracts, with the highest regression coefficient for Acorus calamus. Phytochemical screening identified phenols, terpenoids, and alkaloids as major bioactive components. Overall, Acorus calamus demonstrates strong potential as a natural larvicide for mosquito control programs.