Thomas Thekkevilayil George, Rao Sunder, Lal Shiv
National Institute of Communicable Diseases, Delhi 110054, India.
Jpn J Infect Dis. 2004 Aug;57(4):176-7.
Laboratory bioassay of the essential oil extracted from an indigenous plant, Ipomoea cairica, commonly known as 'Railway creeper', was carried out against the larvae of four vector species of mosquitoes in order to evaluate its mosquito larvicidal effect. Bioassay test revealed that the essential oil of the plant possess remarkable larvicidal properties as it could induce 100% mortality in the larvae of Culex tritaeniorhynchus (100 ppm), Aedes aegypti (120 ppm), Anopheles stephensi (120 ppm), and Culex quinquefasciatus (170 ppm) mosquitoes at concentrations rangeing from 100 to 170 ppm. The LC(50) and LC(90) values estimated for Cx. tritaeniorhynchus, Ae. aegypti, An. stephensi, and Cx. quinquefasciatus were 14.8 and 78.3, 22.3 and 92.7, 14.9 and 109.9, and 58.9 and 161.6 ppm, respectively. The essential oil was found to be most highly toxic to the larvae of Cx. tritaeniorhynchus followed by Ae. aegypti, An. stephensi, and Cx. quinquefasciatus mosquitoes.
对一种本土植物——通常被称为“铁路蔓草”的五爪金龙提取的精油进行了实验室生物测定,以评估其对四种蚊虫媒介幼虫的杀幼虫效果。生物测定试验表明,该植物的精油具有显著的杀幼虫特性,因为在100至170 ppm的浓度范围内,它能使三带喙库蚊(100 ppm)、埃及伊蚊(120 ppm)、斯氏按蚊(120 ppm)和致倦库蚊(170 ppm)的幼虫死亡率达到100%。对三带喙库蚊、埃及伊蚊、斯氏按蚊和致倦库蚊估计的半数致死浓度(LC50)和90%致死浓度(LC90)值分别为14.8和78.3 ppm、22.3和92.7 ppm、14.9和109.9 ppm以及58.9和161.6 ppm。发现该精油对三带喙库蚊幼虫毒性最高,其次是埃及伊蚊、斯氏按蚊和致倦库蚊。