Hannah Gail S. Lavente, Rea Faye Joy S. Guiloreza (March 2010)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Infestation of Golden apple snails (Pomacea canaliculata) posed a serious threat to agricultural sector not only in the Philippines but worldwide. A number of control methods were developed however, none were deemed as the most effective. This study used Asiatic bitter yam (Dioscorea hispida) as a possible molluscicide source against Golden apple snails. The mortality of Golden apple snails in relation to the different concentrations (20 ppm, 40 ppm, 60 ppm, 80 ppm, 100 ppm, 200 ppm, 400 ppm, 600 ppm, 800 ppm, 1000 ppm) of Asiatic bitter yam crade extract was determined. A total of 300 Golden apple snails were used in the study, with ten snails per concentration per replicate. A reference molluscicide Niclosamide was used as standard and dechlorinated water was used as untreated control. An exposure period of 24 hours was given. After the exposure period, snails were transferred to dechlorinated tap water for a recovery period of 24 hours. Reaction of the snails on coming in contact with the test medium is either shock or distress. The distress reaction started with retraction of tentacles and ended in some cases with death. Shock reaction results when snails are immersed in a more concentrated crude water extract which usually resulted in the death of the snails. In general, Asiatic bitter yam extracts have molluscicidal activity against Golden apple snails.