Ovicidal and repellent properties of Coccinia indica Wight and Arn. (Family:Cucurbitaceae) against three important vector mosquitoes.
OBJECTIVE
To determine the larvicidal and repellent activities of Coccinia (C) indica Wight and Arnold (Family:Cucurbitaceae) extract against Culex (Cx.) quinquefasciatus, Aedes (Ae.) aegypti and Anopheles (An.) stephensi.


METHODS
The ovicidal activity was determined against three mosquito species to various concentrations ranging from 50-300 ppm under the laboratory conditions. The hatch rates were assessed 48 h post treatment. The repellent efficacy was determined against three mosquito species at three concentrations viz., 1.0, 2.5 and 5.0 mg/cm2 under the laboratory conditions.


RESULTS
Among five solvent extracts tested, the methanol extract have most promising ovicidal activity. The methanol extract exerted zero hatchability (100% mortality) at 150 ppm for Cx. quinquefasciatus, at 200 ppm for Ae. aegypti and An. stephensi. The methanol extract of C. indica found to be more repellency than the other extracts. A higher concentration of 5.0 mg/cm2 provided 100% protection up to 270 min against Cx. quinquefasciatus and 210 min against Ae. aegypti and An. stephensi, respectively. The results clearly show that repellent activity was dose dependent.


CONCLUSIONS
From the results it can be concluded the crude extract of C. indica was an excellent potential for controlling Cx. quinquefasciatus, Ae. aegypti and An. stephensi mosquitoes.
Division of Vector Biology and Phytochemistry, Department of Zoology, Annamalai University, Annamalainagar, India. drgovind1979@rediffmail.com
M
M
Govindarajan
D000330:Aedes / Q000187:drug effects; D000818:Animals; D000852:Anopheles / Q000187:drug effects; D019662:Cucurbitaceae; D003465:Culex / Q000187:drug effects; D009033:Culicidae / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D007302:Insect Repellents / Q000737:chemistry / Q000494:pharmacology*; D007306:Insecticides / Q000737:chemistry / Q000494:pharmacology*; D007928:Lethal Dose 50; D009032:Mosquito Control / Q000379:methods*; D010063:Ovum / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves; D012997:Solvents / Q000737:chemistry; D013997:Time Factors
D007302:Insect Repellents; D007306:Insecticides; D010936:Plant Extracts; D012997:Solvents