This oilseed rape (canola, Brassica napa) is genetically modified using Agrobacterium tumefaciens to make it herbicide tolerant against Monsanto's herbicide glyphosate (Roundup). It contains two different transgenes to confer the herbicide tolerance: cp4 epsps as well as goxv247.
It is produced by Monsanto and marketed as "Westar Roundup Ready". GT73 is synonym with RT73, as which it was registerd in the US.
Roundup and the risk assessment of glyphosate tolerant crops has come under scrutiny in the last years because Roundup has stronger adverse effects then the active ingredient glyphosate on its own, especially due to effects of adjuvants and surfactants.
GT73 has been authorized for cultivation first in Canada in 1995, and later as well in the US, Japan and Australia. It was authorized as food in the EU in 1997, and as feed in 2005. The feed authorization is still valid until 2017, but the current (October 2009) renewal process covers both food and feed usage.
GT73 is banned in Austria since 2006.
Austria banned GT73 in January 2006