In the present study four types of plant extracts were used to affect three gastropods in Egypt. These plants
were Calotropis procera, Pelargonium graveolens, Ethulia conyzoides and Euphorbia milii.The treated
snails were the land snail or garden snail Eobania vermiculata and the two freshwater ones Lymnaea
caillaudi and Biomphalaria alexandrina.
Traditionally, the land snails demands very high concentrations in comparison with those for the
freshwater snails. There was no effect to the extract of E. milii . The ethanol extract of E. conyzoides was
highly more active than others on the snail E. vermiculata. While, the effect of E. conyzoides and E. milii
on L. caillaudi and B. alexandrina were the most active according to the used concentrations. In
comparison, the extract of E. milii exhibits the highest molluscicidal activity as it caused 50% or more
mortality of L. caillaudi and B. alexandrina with the least concentrations. Moreover, the mortality rate of
L. caillaudi was significantly higher than that of B. alexandrina , demonstrating a deffrential susceptibility
to the ethanol extract of E. milii.