Elango G, Bagavan A, Kamaraj C, Abduz Zahir A, Abdul Rahuman A.
Unit of Bioactive Natural Products, P.G & Research Department of
Zoology, C. Abdul Hakeem College, Vellore District, Melvisharam, 632
509, Tamil Nadu, India.
Insecticides of botanical origin may serve as suitable alternative
biocontrol techniques in the future. The leaf acetone, ethyl acetate,
and methanol extracts of Aegle marmelos (Linn.) Correa ex Roxb,
Andrographis lineata Wallich ex Nees, and Cocculus hirsutus (L.) Diels
were tested for oviposition-deterrent, ovicidal, and repellent
activities against Anopheles subpictus Grassi (Diptera: Culicidae).
The percentage of effective oviposition repellency of 92.60 , 93.04,
95.20, 88.26, 92.80, 94.01, 95.77, 96.93, and 92.54 at 500 ppm and the
lowest repellency of 47.14, 58.00, 56.52, 64.93, 71.09, 66.42, 50.62,
57.62, and 65.73 at 31.25 ppm in acetone, ethyl acetate, and methanol
extracts of Aegle marmelos, Andrographis lineata, and Cocculus
hirsutus, respectively. The oviposition activity index (OAI) value of
acetone, ethyl acetate, and methanol extracts of Aegle marmelos,
Andrographis lineata, and Cocculus hirsutus at 500 ppm were -0.86,
-0.87, -0.90, -0.78, -0.87, -0.86, -0.91, -0.94, and -0.86
respectively. The OAI values revealed that the solvent plant extracts
have deterrent effect, and they caused a remarkable negative response
resulting in oviposition of very few eggs. Mean percent hatchability
of the ovicidal activity was observed 24 h after treatment. The
percent hatchability was inversely proportional to the concentration
of extract and directly proportional to the eggs. Mortality of 100%
with ethyl acetate extract of Aegle marmelos, methanol extracts Aegle
marmelos, Andrographis lineata, and Cocculus hirsutus were exerted at
1,000 ppm. The maximum repellent activity was observed at 500 ppm in
methanol extracts of Aegle marmelos, Andrographis lineata, and ethyl
acetate extract of Cocculus hirsutus, and the mean complete protection
time ranged from 90 to 120 min with the different extracts tested.
These results suggest that the leaf extracts of Aegle marmelos,
Andrographis lineata, and Cocculus hirsutus have the potential to be
used as an ideal ecofriendly approach for the control of the Anopheles
subpictus. Therefore, this study provides first report on the
oviposition, ovicidal, and repellent activities against malaria
vector, Anopheles subpictus of plant extracts from Southern India.
PMID: 19707789 [PubMed - as supplied by publisher]
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