Mustard oil shows efficient spatial repellency against Anopheles stephensi Liston
Kachhwaha N, Meena G, Rajpurohit A, Nagar P
The aim of the study is to determine the repellent property of active ingredient and dose response relationship of mustard oil against Anopheles stephensi. It is the major vector of malaria in urban as well as rural areas of Rajasthan. Five variables of mustard oil were tested against adults of Anopheles stephensi in laboratory conditions maintaining the temperature of 27±30 °C and 70±80% Relative Humidity. Active ingredient were mixed with acetone in different ratios and tested to identify the effective dose range. The concentration were chosen two showing less than 50% spatial repellency response and two showing greater than 50% spatial repellency response excluding 0% and 100% response. For treated 1.5 ml of the repellent active ingredient (acetone and mustard oil) was applied on Whatman filter paper 1 and in other control only diluents was applied in the spatial repellency assay unit. Twenty 3-4 day old adults of Anopheles stephensi were introduced into the central clear cylinder with the help of aspirator and kept for 30 seconds to acclimatize the environment. Spatial activity index (SAI) for each replicate was calculated using the formula and the mean index of each active ingredient dose was analysed by Probit Plane Regression Analysis from which ED50, ED90, ED99 and Carl Pearson Coefficient of Correlation can be estimated. The utility of the mustard oil against the test insect showed repellent behaviour efficiently.