The SA Government has extended the moratorium on commercial plantings of Genetically Modified Canola for a further 2 years, the main reason given being that this will allow SA to remain clean and green. The Victorian and NSW government are now permitting their farmers to grow GM Canola. Presumably, this will allow comparisons so that it becomes clear whether SA gets an advantage in some markets for its Clean and Green image.

Seems to me, however, that this image is somewhat imaginary. When thinking about the possibility of growing GM canola, one rarely asks questions about what kind of canola the GM canola would replace.

My research for the UEA forum on GM crops turned up the information that most canola currently grown in Australia is herbicide resistant (called TT canola, it is tolerant of triazine herbicides). The idea is that this reduces the amount of environmentally damaging tilling required for the crops - weeds are controlled by the use of herbicides to which the crop is resistant. Just like canola which has been genetically engineered to be resistant to herbicide, except that the resistance was bred into the TT canola by traditional breeding methods.

An article entitled Biotechnology and Weed management by R.T.Roush of the Waite Institute contains the following paragraph:

Is classically bred resistance safer or more environmentally friendly than genetically engineered? Just for comparison, atrazine is used on triazine tolerant canola at 1-2 kilograms active ingredient per hectare. Atrazine has a history of ground and surface water contamination, especially in North America. In contrast, glyphosate would probably be used at about 1 kg/ha on the Round-up Ready canola. Rarely cited as an environmental contaminant, the US National Academy of Sciences in 1987 rated glyphosate as among the least risky pesticides to human health. Both canolas offer similar threats from outcrossing to weeds and weedy volunteers. [My emphasis]

In my opinion, the introduction of GM crops should be considered on a case by case basis. And GM crops are not necessarily more damaging to the environment than the varieties they replace.

A useful website about Genetically Modified Organisms is GMO Compass. It takes a European view, with information from round the world.