| Title: | Conspecific and allospecific larval extracts entice mosquitoes to lay eggs and may be used in attract-and-kill control strategy |
| Author(s): | Faierstein GB; Lu W; Sena A; Barbosa RMR; Leal WS; |
| Address: | "Department of Entomology, Instituto Aggeu Magalhaes, Fundacao Oswaldo Cruz, Recife-PE, 50740-465, Brazil. Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA. Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA. wsleal@ucdavis.edu" |
| DOI: | 10.1038/s41598-019-50274-1 |
| ISSN/ISBN: | 2045-2322 (Electronic) 2045-2322 (Linking) |
| Abstract: | "One of the strategies of integrated vector management is to lure gravid mosquitoes for surveillance purposes or to entice them to lay eggs in water containing toxins that kill the offspring (attract-and-kill or trap-and-kill). Typically, the major challenge of this approach is the development of a lure that stimulates oviposition plus a toxin with no deterrent effect. Bacillus thuringiensis var. israelensis (Bti) satisfies the latter criterion, but lures for these autocidal gravid traps are sorely needed. We observed that gravid Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus laid significantly more eggs in cups with extracts from 4th-stage larvae (4 L) of the same or different species. No activity was found when 4 L were extracted with hexane, diethyl ether, methanol, or butanol, but activity was observed with dimethyl sulfoxide extracts. Larval extracts contained both oviposition stimulant(s)/attractant(s) and deterrent(s), which partitioned in the water and hexane phases, respectively. Lyophilized larval extracts were active after a month, but activity was reduced by keeping the sample at 4 degrees C. In the tested range of 0.1 to 1 larvae-equivalent per milliliter, oviposition activity increased in a dose-dependent manner. In field experiments, Ae. aegpti laid significantly more eggs in traps loaded with larval extracts plus Bti than in control traps with water plus Bti" |
| Keywords: | Aedes/*drug effects Animals Bacillus thuringiensis/drug effects Biological Factors/*pharmacology Culex/drug effects Female Larva/*chemistry Mosquito Control/*methods Mosquito Vectors/*drug effects Oviposition/drug effects; |
| Notes: | "MedlineFaierstein, Gabriel B Lu, WeiYu Sena, Andrea K L S Barbosa, Rosangela M R Leal, Walter S eng R01 AI095514/AI/NIAID NIH HHS/ R21 AI128931/AI/NIAID NIH HHS/ Research Support, N.I.H., Extramural England 2019/09/26 Sci Rep. 2019 Sep 24; 9(1):13747. doi: 10.1038/s41598-019-50274-1" |
