Synergistic Molluscicidal Efficacy of Averrhoa bilimbi and Cardiospermum halicacabum Against Pomacea canaliculata

Abstract

The golden apple snail (Pomacea canaliculata) remains one of the most damaging pests of rice in the Philippines, feeding on young seedlings and cutting yields. This study examined whether ethanolic leaf extracts of Averrhoa bilimbi (kamias) and Cardiospermum halicacabum (balloon vine), applied alone and in combination, could kill this snail under laboratory conditions. An experimental design, laid out as a Completely Randomized Design, was used. Snails were exposed to 25%, 50%, and 75% concentrations of the individual and combined extracts, with distilled water (0%) serving as the negative control; each treatment had three replicates of ten snails, and mortality was recorded at 24, 48, and 72 hours. Qualitative phytochemical screening of the combined extract confirmed the presence of tannins, saponins, flavonoids, coumarins, steroids, cardiac glycosides, alkaloids, and carbohydrates. Mortality climbed with both concentration and exposure time. The combined extract killed every snail within 24 hours at the 75% and 50% concentrations, and the 25% treatment reached complete mortality by 48 hours, while the negative control recorded no deaths at all. Taken together, the results point to the combined ethanolic extracts as a strong botanical molluscicide and a promising, environmentally friendlier option for managing golden apple snails in rice fields.