The efficacy of polydimethylsiloxane (aquatain) mosquito formulation on the immature stages of Aedes aegypti (primary vector of dengue) and non-target organism poecilia reticulate (GUPPY)
Date
2013-07-04
Authors
Mudalige, Malka P. S.
Kusumawathie, P.
Jayasooriya, G. A. J. S. K.
Journal Title
Journal ISSN
Volume Title
Publisher
The University of Peradeniya
Abstract
Polydimethylsiloxane (Aquatain), a silicon based compound which produces a monomolecular surface film has been proposed and investigated as a potential mosquito control agent, reducing water surface tension and restricting the ability of mosquito larvae to attach respiratory tube to the water surface. The main objective of this study was to evaluate the efficacy of Aquatain Mosquito Formulation (AMF) on immature stages of primary vector of dengue, Aedes aegypti and the fish Poecillia reticulate (guppy) under laboratory conditions.
Several replicates of different immature stages of field collected Ae.aegypti were exposed to <value> and <value> AMF and the mortalities were observed for 5-7 days. Early stages of Aedes aegypti larvae obtained from eggs collected using ovitraps were introduced to <value> AMF to determine the mortality and further development for 15 days. Six experimental tanks with ten healthy guppies were also treated with <value> AMF and monitored daily for a month to assess the toxicity effect on guppy. All these experiments were carried out as case-control studies.
Mortalities on day 1 for late and early larvae with <value> concentration were 75% (n=100) and 0% (n=50) while day 5 mortalities were 84% and 14% respectively. Mortalities on day 1 for late and early larvae with <value> concentration were 59% (n=100) and 64% (n=50) while the day 5 mortalities were 71% and 74% respectively. 100% pupal mortality was observed within 24 hours of exposure to <value> AMF. The experiment with early larvae exposed to <value> for 15 days duration (n=80) verified the mortality of 3.8% on day 1 and 98.8% on day 15. In control experiments, pupation was initiated on day 5 and adults emerged on day 6 onwards. None of the treated larvae were pupated within 15 days, however only one larva (1.25%) developed into mature larvae after 8 days of exposure. None of the fish exposed to <value> AMF or in control tanks were dead even after one month.
While 100% immediate pupal mortality of Aedes aegypti was achieved the larval mortality was 71 -74% after one week of exposure. A significant retardation of larval development and delayed mortality of early stage larvae after exposure to <value> AMF show that polydimethylsiloxane can be used as an effective control agent against the primary vector of dengue under laboratory conditions. <value> AMF can be recommended as the effective dosage on all immature stages of Aedes aegypti.
Description
Keywords
Polydimethylsiloxane (Aquatain) , Dengue fever , Aedes aegypti , Poecilia reticulata (GUPPY) , Aquatain Mosquito Formula (AMF
Citation
Peradeniya University Research Sessions PURSE - 2012, Book of Abstracts, University of Peradeniya, Sri Lanka, Vol. 17, July. 4. 2012 pp. 284