EXPLOITING THE LARVICIDAL PROPERTIES OF Parthenium hysterophorus L. FOR CONTROL OF DENGUE VECTOR, Aedes albopictus

The larvicidal properties of invasive weed Parthenium hysterophorus L. extract was compared with that of other natural plant extracts; Stevia, Chrysanthemum and Neem extract oil. The extracts obtained from these respective plants under test were dissolved independently to get 20% stock solutions, which was diluted to lower concentrations with tap water. Various doses (0.5, 1.0, 1.5, 2.0, 2.5 and 3%) were tested as per standard dose-response larvicidal bioassays for determining the toxicity in term of LC50/LC90. The results revealed highest LC50 value (2.086 to 2.815 %) and LC90 value (5.836 to 8.533 %) for Stevia extract and the least LC50 (0.849 to 1.455%) and LC90 (1.875 to 2.638 %) for Parthenium extract against Aedes albopictus respectively. Parthenium extract proved superior to the other plants extracts against 3rd and 4th instars larvae of Ae. albopictus in both the exposure periods. The overall, high values of LC50 LC90 for Stevia extract indicating its low toxicity while the minimum LC50 LC90 values by Parthenium extract exhibit its high toxicity against the 3rd and 4th instars larvae of Ae. albopictus in both the 24 48 hours exposure periods. The five tested plants, in terms of efficiency against 3-4 instars mosquito larvae were ranked as Parthenium Chrysanthemum Neem extract neem oil Stevia. These results are helpful in exploiting the use of crude extract obtained from invasive weed (Parthenium) in dengue vector control strategies as effective and safe larvicides in the public health program of dengue vector control. This will not only help in control of the deadly disease but will also be utilized in mechanical control of the invasive weed i.e. P. hysterophorus.