Mosquito larvicidal activity of some common spices and vegetable waste on Culex quinquefasciatus and Anopheles stephensi

Abstract

Objective To investigate the larvicidal activities of crude and chloroform: methanol (1:1 v/v) extracts of some common spices ( Cuminum cyminum, Allium sativum, Zingiber offinale, Curcuma longa) and vegetable waste ( Solanum tuberosum germinated tuber) against Anopheles stephensi and Culex quinquefasciatus mosquito larvae. Methods Larval mortality of above mosquito species were observed after 24, 48 and 72 h of exposure to five concentrations of aqueous extract (0.1%, 0.2%, 0.3%, 0.4% and 0.5%) and four concentrations (25, 50, 75 ppm) of chloroform: methanol (1:1 v/v) extract. The lethal concentration of individual spices or vegetable waste was determined by log-probit analysis (at 95% confidence level) and effect of crude and chloroform: methanol (1:1 v/v) extracts were recorded on non target organisms. Results Relative mortality rate of both larval mosquito species were recorded in the following sequences: Cuminum cyminum > Allium sativum > Zingiber offinale, Curcuma longa > Solanum tuberosum germinated tuber for crude extract, and efficacy of chloroform: methanol (1:1 v/v) extract were as follows: Curcuma longa > Zingiber offinale > Solanum tuberosum germinated tuber > Cuminum cyminum > Allium sativum. Conclusions Crude and chloroform: methanol (1:1 v/v) extract of Cuminum cyminum, Allium sativum, Zingiber offinale, Curcuma longa and Solanum tuberosum germinated tuber can be recommended effectively in mosquito control programmes at very low concentrations. No mortality and other abnormalities were noticed on non target organisms and further studies are needed to investigate the chemical structure of active principal which are responsible for larvicidal activity.