EFFICACY OF SELECTED PLANT EXTRACTS IN THE OKRA PEST, Zonabris pustulata (THUNBERG)

JEYAPARVATHI S.¹, UMAYAL P.M.², BASKARAN S.³, BAKAVATHIAPPAN G.A.^4
1Post Graduate and Research Department of Zoology, Ayya Nadar Janaki Ammal College, Sivakasi - 626 124, TN, India.
²Post Graduate and Research Department of Zoology, Ayya Nadar Janaki Ammal College, Sivakasi - 626 124, TN, India.
³Post Graduate and Research Department of Zoology, Ayya Nadar Janaki Ammal College, Sivakasi - 626 124, TN, India.
⁴Post Graduate and Research Department of Zoology, Ayya Nadar Janaki Ammal College, Sivakasi - 626 124, TN, India.

Received : 06-12-2012     Accepted : 15-07-2013     Published : 06-08-2013
Volume : 1     Issue : 1       Pages : 16 - 20
World Res J Pharmaceut Res 1.1 (2013):16-20

The pesticidal activity of five plant extracts like Azadirachta indica (L.), Ocimum sanctum (L.), Cynodon dactylon (L.), C. gigantea and Acalphya indica (L.)on blister beetle Z. pustulata were studied. The mortality of Z. pustulata varied with varied concentration of plant extract. For instance, high pesticidal activity was recorded from the crude extracts of A. indica, O. sanctum, C. dactylon, C. gigantea and A. indica. During A. indica treatment, the highest mortality was occurs during 48 hrs. and the lowest mortality was occurs during 72 hrs. The percentage of mortality was different and it depended upon time to time from 24 hrs. to 72 hrs. The plant extract of C. gigantea has high insecticidal activity than other plant products. The highest percentage of mortality was occurred when the blister beetle was treated with C. gigantea. The plant extract of A. indica has the lowest pesticidal activity than other plant products. The lowest percentage of mortality occurred, when the blister beetle was treated with A. indica. After 24 hrs., 48 hrs., and 72 hrs., the highest mortality occurs in Z. pustulata. The percentage of death occurred during O. sanctum treatment was after 24 hrs. treatment. The anti-feedant activity of C. gigantea leaf extract was better than that of leaf extract 24 hrs. after treatment; however, 48 hrs. later the effect was vice versa and the leaf extract was more effective as an anti-feedant. The botanical treatments also showed mortality as observed 72 hrs. after treatment until ten days. In conclusion, the three botanical pesticides were effective in the control of Z. pustulata, though they do not match the effectiveness of the synthetic pesticide. These botanical pesticides are affordable to low-income farmers. These natural pesticides have the potential for use in agriculture. In this paper, it has been suggested that botanical insecticides should prove most beneficial for farmers in developing countries.