Bioefficacy of essential oil from Polygonum hydropiper L. against mosquitoes, Anopheles stephensi and Culex quinquefasciatus

The biological activity of essential oil extracted from the leaves of Polygonum hydropiper and a compound, confertifolin, isolated from this plant was bioassayed against larva of mosquitoes, Anopheles stephensi and Culex quinquefasciatus. The essential oil showed the LC50 values of 189 and 243 ppm; 217 and 242 ppm, confertifolin (6,6,9a-trimethyl-4,5,5a,6,7,8,9,9a-octahydronaphtho[1,2-c]furan-3(1H)-one) showed the LC50 values of 2.40 and 3.09 ppm; 4.07 and 4.18 ppm against the second and fourth instar larvae of An. stephensi and Cx. quinquefasciatus, respectively. At 10 ppm confertifolin showed ovicidal activity of 100, 98.6 and 86.4% against An. stephensi and 100, 100 and 75.2% against Cx. quinquefasciatus on 0-6, 6-12 and 12-18 h old eggs; the repellent activity persisted for 314.6 and 319.0 mm; oviposition deterrent activity was 97.2 and 99% and adulticidal activity was 100 and 100% against An. stephensi and Cx. quinquefasciatus, respectively. The results were statistically significant. Confertifolin could be considered for use in the control of human vector mosquitoes. (C) 2013 Elsevier Inc. All rights reserved.