Larvicidal, repellent, and histopathologic effects of Citrullus colocynthis against the malaria vector.

This research is conducted to determine the larvicidal, repellent and pathological effects of fruit extracts of C. colocynthis on malaria vector mosquito, Anopheles stephensi Liston, 1901. The fruit water and ethanol extract of C. colocynthis were concentrated for larvicidal and repellent activities on human volunteer against An. stephensi. The temephos larvicide was tested as the positive control. A concentration of 300 mg/L had full-scale mortality and the most toxic effect. The LC₅₀ and LC₉₀ values of C. colocynthis water and ethanol extracts were 180and 283 mg/L, respectively. The LC₅₀ and LC₉₀ values of temephos were 0.2706 and 1.6932 mg/L, respectively. The ED₅₀ and ED₉₀ values of the plant extract were 0.2 and 1.3 mg/cm², respectively. Thin sections from treated larvae exhibited gross histopathologic effects of C. colocynthis fruit extracts on gut epithelial cell layer by vacuolization of foregut cuboidal and midgut columnar cells. This study suggested that the fruit extracts of C. colocynthis had significant larvicidal and repellent activity to be used as an ideal approach to control the malaria vector mosquito. [ABSTRACT FROM AUTHOR]