EFFECT OF RICINUS COMMUNIS EXTRACTS ON WEIGHT AND MORTALITY OF SCYPHOPHORUS ACUPUNCTATUS (COLEOPTERA: CURCULIONIDAE).

Abstract

The agave snout weevil Scyphophorus acupunctatus is considered the major insect pest of the tequila agave Agave tequilana Weber var. azul and other agavaceae. The effect of hydroethanoholic extracts from leaves and seed of wild (WV) and Mirante variety (MV) castor bean Ricinus communis L. on adults mortality and weight was assessed. When extracts were applied on agave tissue, mortality was not significant at concentrations of 0.1 to 100,000 ppm and at the tested frequencies. In the acute application, extracts from MV leaves and seed caused the largest weight loss. Within the second application, insect weight decreased even more with all of the extracts tested, however, this did not occur with the third application of the extracts where weight gains and losses of adult weevils were recorded. It is concluded that these extracts do not have toxic activity on adult weevils, but they do have an effect on weevil weight.