Ceratophyllum demersum L. Extract as a Botanical Insecticide for Controlling the Maize Weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

Insecticidal activities of methanol and water extracts, obtained from in vitro propagation of Ceratophyllum demersum L. on maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) were laboratory studied. In vitro whole plant regeneration was obtained from nodal explants of C. demersum cultured on liquid Murashige and Skoog medium (MS) treated with various combinations of 6-Benzylaminopurine (BAP) and 1-Naphthaleneacetic acid (NAA). Different, concentrations (2.5, 5, 10 and 20 mg/ml) of C. demersum extracts were tested. The highest mortality (100%) caused were determined by both extracts at the concentrations of 10 and 20 mg/ml after 96 h of exposure. LC50 of methanol and water extracts after 96 h were 1.720 and 1.015 mg/ml, respectively. It was detected that mortality was correlated with concentration and exposure time. These findings suggest that C. demersum extract could be considered as an effective biocontrol agent and could be used as an alternative to chemical insecticides.