Abstract

L. K. Olofintoye

The molluscicidal activities of ethanoic and methanoic extracts of the leaf, stem bark and root of Securidaca longepedunculata (Polygalaceae) and Tephrosia brateolata (Fabaceae) against bred Bulinus globosus measured 0.50 - 0.90 mm in size, were investigated. The snails were exposed to a serial dilution of 0.1, 0.2, 0.5, 1.0, 2.0, 3.0, 5.0, 7.5 and 10.0 ppm of the ethanoic and methanoic extracts of the leaf, stem bark and root of S. longepedunculata and T. bracteolata for 24 h. All tested extracts showed varied snail mortality rates with the concentration of ethanoic and methanoic extracts of the plants parts from 0.0 - 100.0%. The lethal concentration LC50 values ranged from 0.15 - 0.60 ppm and LC90 values from 0.80 - 6.90 ppm for both ethanoic and methanoic extracts of S. longepedunculata for 24 h. The two plants showed significant difference (p < 0.05) in the mortality rates of the snails (B. globosus).