Aphidicidal potential of Azadirachta indica, Adhatoda vasica, Vitex negundo, Parthenium hysterophorus and Lantana camara against mustard aphid, Lipaphis erysimi Kaltenbach (Hemiptera:Aphididae)

Abstract

Use of eco-friendly naturally occurring plant products in the management of the mustard aphid, Lipaphis erysimi Kaltenbach (Hemiptera:Aphididae) under laboratory conditions was carried out. The results revealed that the nymphs and adults mortality of mustard aphid varied significantly with three different concentrations (0.5, 1.0 and 2.0%) of five plant products. The mortality was high with seed kernel extracts of neem, Azadirachta indica killed nymphs and adults of L. erysimi (70.82 %) followed by leaves extracts of lagundi, Vitex negundo Linn. (69.40 %), leaves extract of Parthenium hysterophorus Linn. (65.38 %), leaves extract of arusa, Adhatoda vasica Nees. (55.81%), aerial parts of aripple, Lantana camara Linn. (51.70%) and untreated control (1.5 %), respectively. The seed kernel extracts of A. indica differed significantly from the remaining ones except V. negundo from which it does not differ significantly to one another. The effects of carrot grass, P. hysterophorus was recorded moderate aphidicidal action while L. camara caused the lowest mortality of nymphs and adults of L. erysimi among all treated natural products. Of the five plant products tested A. indica performed better under all the experimental conditions where as untreated control gave only 01.5% aphid mortality. The concentrations 2.0% are superior to concentration 1.0% and 0.5% concentrations. Similarly maximum aphid mortality was observed after 24 hours of exposure and minimum after 6hours. The exposure periods of 24 hours was significantly superior to 12 hours and 6 hours in both control and plant products.