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The effect of seston on mortality of Simulium vittatum (Diptera: Simuliidae) from insecticidal proteins produced by Bacillus thuringiensis subsp. israelensis.

Authors :
Iburg JP
Gray EW
Wyatt RD
Cox JE
Fusco RA
Noblet R
Source :
Environmental entomology [Environ Entomol] 2011 Dec; Vol. 40 (6), pp. 1417-26.
Publication Year :
2011

Abstract

Water was collected from a site on the Susquehanna River in eastern Pennsylvania, where less-than-optimal black fly larval mortality had been occasionally observed after treatment with Bacillus thuringiensis subsp. israelensis de Barjac insecticidal crystalline proteins (Bti ICPs). A series of experiments was conducted with Simulium vittatum Zetterstedt larvae to determine the water related factors responsible for the impaired response to Bti ICPs (Vectobac 12S, strain AM 65-52). Seston in the water impaired the effectiveness of the ICPs, whereas the dissolved substances had no impact on larval mortality. Individual components of the seston then were exposed to the larvae followed by exposure to Bti ICPs. Exposure of larvae to selected minerals and nutritive organic material before ICP exposure resulted in no significant decrease in mortality. Exposure of larvae to silicon dioxide, cellulose, viable diatoms, and purified diatom frustules before Bti ICP exposure resulted in significant reductions in mortality. Exposure of larvae to purified diatom frustules from Cyclotella meneghiniana Kützing resulted in the most severe impairment of mortality after Bti ICP exposure. It is postulated that frustule-induced impairment of feeding behavior is responsible for the impairment of larval mortality.

Details

Language :
English
ISSN :
1938-2936
Volume :
40
Issue :
6
Database :
MEDLINE
Journal :
Environmental entomology
Publication Type :
Academic Journal
Accession number :
22217757
Full Text :
https://doi.org/10.1603/EN11167