Insectifuge Biopotency of Chrysanthemum cinerariifolium, Cichorium intybus, Inula racemosa and Tagetes minuta extractives against okra aphid, Aphis gossypii Glover (Hemiptera: Aphididae)

Abstract

In the present investigation alcoholic extract of ten indigenous naturally occurring asteraceous plants viz., aerial parts of Acmella paniculata (Wall ex DC.) R.K.Jansen, Cichorium intybus (L.), Chromolaena odorata Linn., Chrysanthemum cinerariifolium (trev.) Vis., Inula racemosa Hook. F., Mantisalca duriaeri Birq. Et Cavill., Rechardia tingitana (L.) Roth, Rhaponticum acaule (L.) DC, Scorzonera undulate Vahl, and Tagetes minuta Linn. Extractives were prepared under the laboratory conditions. For testing the repellent effect on okra leaves were used as food against nymph and adults of Aphis gossypii Glover. After four hours nymph and adults of A. gossypii were release and the data was collected on the number of nymph and adults of A. gossypii reached and repelled at each treated food. All the comparisons were made with control. It is evident from the results of repellent test against nymph and adults of Aphis gossypii Glover that all the asteraceous extractives showed a good repellent property, when compared with the control. The repellent properties were observed based on their minimum EC50 values as: C. intybus (0.1359) > I. racemosa (0.1531) > T. minuta (0.1833) > M. duriaeri (0.3208) > S. undulate (0.4123) > A. paniculata, (0.6365) > R. acaule (0.6469) > R. tingitana (0.7124) > C. odorata (0.9025), respectively. The relative EC50 values of the above extracts are in descending order, 6.6409 > 5.8948 > 4.9236 > 2.8132 > 1.4179 > 1.3951 > 1.2668 > 1.2161 > 1.1668 > 1.0000 times as repellents, whereas A. paniculata was taken as a unit. C. intybus and I. racemosa extract significantly reduced the population of treated nymphs and adults of Aphis gossypii on okra vegetable compared to the untreated control.