Insecticidal efficacy of Rubus steudneri and Rubus apetalus against Aedes (Diptera: Culicidae) and Culex (Diptera: Culicidae) mosquitoes

Introduction and Aim: Rubus steudneri Schweinf. and Rubus apetalus Poir. belonging to the family Rosaceae is one of the ethnomedicinal plants used widely in Ethiopia as food, for construction and as medicine. To the best of our knowledge, insecticidal activity of R. steudneri and R. apetalus has not been investigated so far. In this study, we report insecticidal efficacy of R. steudneri and R. apetalus in terms of larvicidal effect against II and III instar larvae of Aedes and Culex mosquitoes. Materials and Methods: The shade-dried and powdered leaves were extracted using methanol by maceration process. Insecticidal activity of leaf extract was determined by larvicidal assay against II and III instar larvae of Aedes and Culex species. LC50 and LC90 values were calculated. Results: The leaf extract of both Rubus species exhibited concentration dependent larvicidal effect. II instar larvae were shown to be highly susceptible than III instar larvae. Among leaf extracts, extract of R. steudneri exhibited marked insecticidal activity when compared to extract of R. apetalus as revealed by lower LC50 and LC90 values. Culex larvae displayed marked susceptibility to leaf extracts when compared to Aedes larvae. Conclusion: Marked larvicidal effect was observed against larvae of Culex species when compared to Aedes species as indicated by lower LC50 and LC90 values. It is evident that the leaf extracts of both Rubus contain insecticidal principles.