In a message dated 2/14/2011 7:46:05 P.M. Central Daylight Time,  
[log in to unmask] writes:


NOTE: Chemical/GM company Dow has come up with a 'solution' to the  problem 
of glyphosate-resistant weeds, which are fast making GM Roundup Ready  
technology redundant. The company has identified a gene that, when engineered  
into maize plants, makes them tolerate being doused with 2,4-D and related  
herbicides, as detailed in a study by Dow employees (abstract below). This is 
 touted as an important advance that "can help preserve the productivity 
and  environmental benefits of herbicide-resistant crops". The authors claim 
in  their study that 2,4-D is safe - citing two non-peer reviewed  sources.
---
---
Wright, T. R., G. Shan, et al. (2010). "Robust crop  resistance to 
broadleaf and grass herbicides provided by aryloxyalkanoate  dioxygenase 
transgenes." Proc Natl Acad Sci U S A 107(47):  20240-20245.

Free in full:   http://www.pnas.org/content/107/47/20240.full.pdf+html

Engineered  glyphosate resistance is the most widely adopted genetically 
modified trait in  agriculture, gaining widespread acceptance by providing a 
simple robust weed  control system. However, extensive and sustained use of 
glyphosate as a sole  weed control mechanism has led to field selection for 
glyphosate-resistant  weeds and has induced significant population shifts to 
weeds with inherent  tolerance to glyphosate. Additional weed control 
mechanisms that can  complement glyphosate-resistant crops are, therefore, 
urgently needed.  2,4-dichlorophenoxyacetic acid (2,4-D) is an effective low-cost,  
broad-spectrum herbicide that controls many of the weeds developing 
resistance  to glyphosate. We investigated the substrate preferences of bacterial  
aryloxyalkanoate dioxygenase enzymes (AADs) that can effectively degrade 
2,4-D  and have found that some members of this class can act on other widely 
used  herbicides in addition to their activity on 2,4-D. AAD-1 cleaves the  
aryloxyphenoxypropionate
family of grass-active herbicides, and AAD-12 acts  on pyridyloxyacetate 
auxin herbicides such as triclopyr and fluroxypyr. Maize  plants transformed 
with an AAD-1 gene showed robust crop resistance to  aryloxyphenoxypropionate 
herbicides over four generations and were also not  injured by 2,4-D 
applications at any growth stage. Arabidopsis plants  expressing AAD-12 were 
resistant to 2,4-D as well as triclopyr and fluroxypyr,  and transgenic soybean 
plants expressing AAD-12 maintained field resistance to  2,4-D over five 
generations. These results show that single AAD transgenes can  provide 
simultaneous resistance to a broad repertoire of agronomically  important classes of 
herbicides, including 2,4-D, with utility in both monocot  and dicot crops. 
These transgenes can help preserve the productivity and  environmental 
benefits of herbicide-resistant  crops.

................................................................
Website:  http://www.gmwatch.org
Profiles:  http://www.powerbase.info/index.php/GM_Watch:_Portal
Twitter:  http://twitter.com/GMWatch
Facebook:  http://www.facebook.com/pages/GMWatch/276951472985?ref=nf

This email  should only be sent to those who have asked to receive it.
To unsubscribe,  contact [log in to unmask], specifying which list you wish 
to unsubscribe  from.


 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
To unsubscribe from the IOWA-TOPICS list, send any message to:
[log in to unmask]

Check out our Listserv Lists support site for more information:
http://www.sierraclub.org/lists/faq.asp

Sign up to receive Sierra Club Insider, the flagship
e-newsletter. Sent out twice a month, it features the Club's
latest news and activities. Subscribe and view recent
editions at http://www.sierraclub.org/insider/