Larvicidal and oviposition activity of Cassia obtusifolia Linn (Family: Leguminosae) leaf extract against malarial vector, Anopheles stephensi Liston (Diptera: Culicidae).
The ethanolic leaf extract of Cassia obtusifolia was investigated for their larvicidal and oviposition deterrence effects against Anopheles stephensi. Concentrations ranging from 25 to 125 mg/l were assessed at 24 h post-treatment against late third instar larvae. The leaf extract had significant larvicidal effect with LC(50) and LC(90) values were 52.2 and 108.7 mg/l, respectively. In oviposition behaviour study, four different concentrations ranging from 100 to 400 mg/l were studied against gravid female mosquitoes. The results of oviposition study indicated that the leaf extract showed concentration dependent oviposition deterrent activity. At higher concentration (400 mg/l) showed 92.5% effective repellency against oviposition, followed by 300, 200 and 100 mg/l showed 87.2%, 83.0% and 75.5%, respectively. The larvicidal and oviposition deterrent effect of C. obtusifolia against A. stephensi make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.
Rajkumar
S
S
Department of Zoology and Wildlife Biology, A.V.C. College, Mannampandal, 609 305 Tamilnadu, India. drrajvec@rediffmail.com
Jebanesan
A
A
D000818:Animals; D000852:Anopheles / Q000187:drug effects*; D002366:Cassia / Q000737:chemistry*; D007302:Insect Repellents / Q000302:isolation & purification / Q000494:pharmacology*; D007306:Insecticides / Q000302:isolation & purification / Q000494:pharmacology*; D007928:Lethal Dose 50; D010058:Oviposition / Q000187:drug effects; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D016019:Survival Analysis
D007302:Insect Repellents; D007306:Insecticides; D010936:Plant Extracts