Vol. 2, Issue 1, Part A (2020)

In the present study, the Larvicidal activity of biosynthesized silver nanoparticle using leaf extracts of Andrographis alata was used against Culex quinquefasciatus in order to carry out larvicidal activity. Methanolic leaf extract of Andrographis alata along with AgNPs was significantly inhibits the adult emergence. The percentage of adult emergence inhibition were 08.0±1.3, 14.0±1.3, 30.0±1.5, 45.5±1.5, 58.0±3.2, 76.0±2.4 and 96.0±2.3 % at different concentration viz., 0.1, 0.2, 0.3, 0.4 and 0.5 ppm against the larvae of Cx.quinquefasciatus. The LC₅₀ values of the methanolic leaf extract of Andrographis alata along with silver nanoparticle was 460.05 ppm against late third larva Cx. quinquefasciatus. The chi-square value 0.25 was significant at p<0.05 level. In AgNPs, the LI₅₀ value was 623.12 ppm and the EI₉₀ value was 1254.35. The chi –square value 0.03.65 was significant at p<0.05 level. From the result it is concluded that the plant extract and silver nanoparticles were effectively inhibit the emergence of adult from larvae of C. quinquefasciatus.