This is the true concern about GMO, since people royally suck at introducing new species into ecosystems, an action that often cannot be undone.
Also... where else would you plant it?
I definitely prefer the Big Ag corps answering that question... and until they have an answer don't f*ck with the one environment we live in.
Definitely not. Its genome differs from its wild ancestor in many respects. To name just one, like most domestic grains it's resistant to "shattering" (i.e., the seeds tend to remain attached to the plant, rather than falling off and/or being scattered when the plant is blown by the wind). That is a great feature for farmers, but means that the plant would likely go extinct in short order if left to itself (because the seeds wouldn't be scattered on the ground).