Thanks for the very informative reply from Allen Dick on Canola modified by
traditional methods to be resistant to a particular herbicide.  What happens
the following years when seed spilled in harvesting germinates and is a weed
in other crops?  You can't use the herbicide to get rid of it.  Is there any
transfer of the resistance to closely related weed species such as charlock
(I don't know whether this grows in Canada but it is very common in UK)
Chris Slade