Lethal and pre-lethal effects of a fungal biopesticide contribute to substantial and rapid control of malaria vectors

Simon Blanford, Wangpeng Shi, Riann Christian, James Harold Marden, Lizette L. Koekemoer, Basil D. Brooke, Maureen Coetzee, Andrew Fraser Read, Matthew Brian Thomas

Research output: Contribution to journalArticle

56 Citations (Scopus)

Abstract

Rapidly emerging insecticide resistance is creating an urgent need for new active ingredients to control the adult mosquitoes that vector malaria. Biopesticides based on the spores of entomopathogenic fungi have shown considerable promise by causing very substantial mortality within 7-14 days of exposure. This mortality will generate excellent malaria control if there is a high likelihood that mosquitoes contact fungi early in their adult lives. However, where contact rates are lower, as might result from poor pesticide coverage, some mosquitoes will contact fungi one or more feeding cycles after they acquire malaria, and so risk transmitting malaria before the fungus kills them. Critics have argued that 'slow acting' fungal biopesticides are, therefore, incapable of delivering malaria control in real-world contexts. Here, utilizing standard WHO laboratory protocols, we demonstrate effective action of a biopesticide much faster than previously reported. Specifically, we show that transient exposure to clay tiles sprayed with a candidate biopesticide comprising spores of a natural isolate of Beauveria bassiana, could reduce malaria transmission potential to zero within a feeding cycle. The effect resulted from a combination of high mortality and rapid fungal-induced reduction in feeding and flight capacity. Additionally, multiple insecticide-resistant lines from three key African malaria vector species were completely susceptible to fungus. Thus, fungal biopesticides can block transmission on a par with chemical insecticides, and can achieve this where chemical insecticides have little impact. These results support broadening the current vector control paradigm beyond fast-acting chemical toxins.

Original languageEnglish (US)
Article numbere23591
JournalPloS one
Volume6
Issue number8
DOIs
StatePublished - Aug 29 2011

Fingerprint

Biological Control Agents
biopesticides
Fungi
malaria
Malaria
Insecticides
Malaria control
Culicidae
fungi
insecticides
Spores
Mortality
spores
Beauveria
Tile
Insecticide Resistance
Pesticides
vector control
tiles
insecticide resistance

All Science Journal Classification (ASJC) codes

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

Cite this

Blanford, Simon ; Shi, Wangpeng ; Christian, Riann ; Marden, James Harold ; Koekemoer, Lizette L. ; Brooke, Basil D. ; Coetzee, Maureen ; Read, Andrew Fraser ; Thomas, Matthew Brian. / Lethal and pre-lethal effects of a fungal biopesticide contribute to substantial and rapid control of malaria vectors. In: PloS one. 2011 ; Vol. 6, No. 8.
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Lethal and pre-lethal effects of a fungal biopesticide contribute to substantial and rapid control of malaria vectors. / Blanford, Simon; Shi, Wangpeng; Christian, Riann; Marden, James Harold; Koekemoer, Lizette L.; Brooke, Basil D.; Coetzee, Maureen; Read, Andrew Fraser; Thomas, Matthew Brian.

In: PloS one, Vol. 6, No. 8, e23591, 29.08.2011.

Research output: Contribution to journalArticle

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