The larvicidal activity of powders and aqueous-extracts different parts of four plant species fruits against Anopheles arabiensis Paton (Diptera: Culicidae) larvae from Wad Medani, CentralSudan

摘要

According to WHO, populations of Anopheles arabiensis Paton (Diptera: Culicidae) from the Gezira state, central Sudan, produced strains showing resistance to a wide range of insecticides. Natural products are substances or combinations of substances and elements found in nature, and used for the purpose of maintaining or improving health, treating or preventing diseases and control of vectors. In the present work, the larvicidal potentialies of four different local plants fruits were investigated using different morphological parts (seeds, whole fruit, pericarp) and in the forms of powders or aqueous -extracts. These plants were: orange (Citrus sinensis L.), Pomegranate (Punica granatum L.), bitter apple (Citrullus colocynthis Schrad). and pepper (Capsicum annuum L.).The standard methods of WHO for rearing and assesment of mosquitoes susceptibility were carefully followed. The results revealed that the LD50 for bitter apple fruit powder was 144.2 mg/L, for pepper fruit 165.3 mg/, for orange seeds powder 255.9 mg/L, for pomegranate seeds powder 718.7 mg/L, for orange pericarp powder (980.7 mg/L and, lastly for pomegranate pericarp powder was 1266.9 mg/L. The effects of the treatments on the larvae showed significant differences in their persistence in water. Pepper fruit powder killed 50-80% within the first 3 days, whereas orange seeds powder killed 35-100% within the first 6 days. The bitter apple powder effect persited for 2 days only (85 and 55% for days 1 and 2, respectively) and, then drastically declined (15 and 10% for days 3 and 4, respectively). More investigations are needed to isolate the active ingredients of each powder and subject them to bioassay.