The molluscicidal activity of seed pods of Swartzia madagascariensis on Marisa cornuarietis.

The molluscicidal potency of ground seed pods of Swartzia madagascariensis was tested in the laboratory against Marisa cornuarietis, a well known competitor and/or predator of pulmonate intermediate hosts of schistosomiasis. Results showed that a minimum concentration of 1.6g ground pods/1 was required to cause 100% mortality in M. cornuarietis. This concentration was by far over and above what is required (ie, 100 mg ground pods/1) to kill 10% of the pulmonate hosts of schistosomiasis. It seems that the application of S. madagascariensis at a concentration inimical to pulmonates (ie, 100 mg ground ponds/1 or slightly higher) in habitats where M. cornuarietis is introduced may not adversely affected to competitor snail population. Hence, the prospect of using S. madagascariensis in conjunction with M. cornuarietis against pulmonate snail hosts is conceived and tentatively recommended.