Christine Kyarimpa Mugumya
Kyambogo University, Uganda
Title: Essential oil and composition of Tagetes minuta; A larvicidal assay on Anopheles gambiae
Biography
Biography: Christine Kyarimpa Mugumya
Abstract
As the search for alternatives to synthetic medicine goes on, several plants have been identified as possible natural insecticides, among which is Tagetes minuta. In this study Essential oil from Tagetes minuta was obtained by Hydrodistillation. It was tested against the 3rd and 4th instar Anopheles gambae to determine the larvicidal activity. Six different concentrations of this essential oil were studied and compared with that of Methyl Parathion, a synthetic organophosphorus insecticide for 24 hours. GC-MS results indicated the presence trans-ocimen 15.90%, I-verbanone 15% of limonene 8.02%, tegetone 3.56%, and 2-pinen-4-one 7.84% as the major compounds in the essential oil. The LC50 was 2.9mg/l while the LC90 was 3.29mg/l after 2 hours of exposure. After 6 hours of exposure, the LC50 and LC90 were 2.31mg/l and 2.68mg/l, respectively, while after 12 hours, it was 1.49 and 1.82mg/l, respectively. After 24 hours, the LC50 and LC90 were not determined because the mortality was 100%. Therefore effectiveness of essential oil from Tagetes minuta is comparable to that of synthetic insecticides and can be studied further in lieu of becoming a possible alternative.