Gene silencing pesticides are pesticides that use
gene silencing, and
RNA interference (RNAi) in particular to target individual species while leaving other species unharmed.
[EOS magazine, June 2010]
History
In 1998, it was found that double-stranded RNA, injected to worms influenced the natural gene sequence in such a way that it was silenced. Equally surprising was that the genes were also silenced when the worms ingested the dsRNA.
Steven Whyard, working for CSIRO Entomology at that time, then also tried it with insects. To his surprise, this also worked, and they just invented something that had huge implications. They then patented the technology and by 2006, it was used in pesticides. Two articles were then also published that confirmed that the effect was powerful enough to protect plants from pests.
Examples
* Monsanto and Devgen developed a gene silencing pesticide against ''
Diabrotica virgifera
''Diabrotica virgifera'' is a species of beetle in the family Chrysomelidae. It is an agricultural pest species that attacks maize
Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North Ameri ...
''
* A team, led by Xiao-Ya Chen fed gossypol with dsRNA targeting the gene for cytochrome P450 to
bollworm
Bollworm is the common term for a moth larva that attacks the fruiting bodies of certain crops, especially cotton.
The most common moths known as bollworms are:
* Red or Sudan bollworm, '' Diparopsis castanea''
* Rough bollworm, '' Earias perhuege ...
larvae to kill them off
* Devgen has developed a gene silencing pesticide against the
Colorado beetle
The Colorado potato beetle (''Leptinotarsa decemlineata''), also known as the Colorado beetle, the ten-striped spearman, the ten-lined potato beetle, or the potato bug, is a major pest of potato crops. It is about long, with a bright yellow/o ...
Application
Besides directly killing the pests by poisoning the food of insects with RNAi, there are also other ways on how gene silencing pesticides can kill a pest. For example, a research study by
Michael Scharf
Michael P. Scharf (born April 25, 1963 in Shaker Heights, Ohio) is co-dean, Joseph C. Hostetler – BakerHostetler professor of law, and the director of the Frederick K. Cox International Law Center at Case Western Reserve University School of ...
found that it was possible to eradicate termites by using RNAi which disables the Hex-2-gene; this transforms worker termites into soldier termites. A colony with too many soldier termites (apparently more than about 10%) does not have enough remaining worker termites to adequately feed the colony.
References
{{pesticides
Biopesticides
Plant toxin insecticides
Garden pests