Comparative Efficacy of Leaf Extracts of Different Tobacco Varieties Against Mustard Aphid ( Lipaphis erysimi Kalt.)

In this study, field and laboratory experiments were carried out in order to develop a biological control strategy against mustard aphid by using extracts of five tobacco varieties (Beeri wala, Balkhi, Pattay wala, Desi Tobacco and Hazropattar). Two extraction methods were used: extraction through boiling of leaves (ETBL) and extraction through overnight water soaking of leaves (ETOWSL). Mustard variety (Early Mustard) was cultivated with eleven treatments of three replicates each. Laboratory experiments were conducted to confirm the mortality due to the extract of tobacco varieties and the efficient type of extraction. All treatments were found to be effective in field against mustard aphid. Extracts of Pattay wala, Balkhi and Desi tobacco obtained through ETBL remained effective up to a week, whereas the extracts of Hazropattar, Balkhi, Pattay wala and Desi tobacco obtained through ETOWSL were found to be effective up to two weeks after treatment. The highest reduction in aphid population was noted by Pattay wala tobacco and the lowest reduction was seen by Desi tobacco. Almost the same trend of effectiveness was recorded during 2nd spray. In laboratory conditions 100% mortality of aphids was observed within three days under all treatments. The results of this study could be useful in an integrated pest management program for the management of mustard aphid Lipaphis erysimi.