An aqueous extract prepared from Kernels of the fruit of
Thevetia peruviana (Pers.) Schumann (Family : Apocynaceae)
was found under experimental conditions, to be toxic to the slug
Laevicaulis alte (Ferussac) and the snail Achatina fulica
Bowdich, the important agrihorticultural pests of Indo-Pacific
countries. Concentrations as low as 1% (w/v) killed all the slugs
exposed in less than 981.00 (+/- SD 22.76) min, and 2% of the
extract killed 100% of the slugs L. alte and 50%, 50% and
30% of the snail A. fulica in between 92.34 (+/- SD 6.63) -
321.33 (+/- SD 4.14) and 271.20 (+/- SD 17.54) - 298.26 (+/- SD
16.69) min respectively. The most effective concentration of the
extract was 20%; it killed 100% of exposed slugs and snails within a
short time (40-50 and 90-1440 min respectively) when the extract was
exposed on the soil in experimental trays or when it was applied to
potato slices offered as food to the gastropods.