GENTECH archive


reply to archive 1129

Dear Mr Jennings:

I am afraid that I don't share your religious views about the nature of the creator. While I respect your right to hold them, I object to your aim (and that of those who share similar views) to force the rest of us to live by your views, just as I reject the equally extremist and stridently held views of Creationists and religious conservatives who would restrict a woman's right to control her own reproduction.

With respect to "superweeds", I don't know what Barton of Monsanto actually said, only what has been forwarded to this server. However, the comments attributed to Barton confuse insect and herbicide resistance. I presume that what Barton actually said was something like that "some GM crops can cross-breed with native plants, creating hybrids resistant to some weedkillers", but "superweeds" (hybrid plants resistant to HERBicide) were not an issue since they could always be sprayed with other weedkillers to which they were not resistant", and that "insects are capable of developing a resistance to plants genetically engineered to kill them".

I know of only one crop that can outcross to weeds in any of the areas in which it is currently grown, and that is canola. I have invested more than $100,000 of grant funds into testing for this in Australia (tests have now been conducted on more than 50 million seeds) and we cannot find ANY cases of outcrossing under Australian conditions, so not even canola is a universal threat for superweeds. Where outcrossing occurs, the theat must be considered in any plan to release the crop, and I would support the rejection of release of crops for which this risk is significant.

However, outcrossing does not occur for soybeans, cotton, potatoes, or corn (the only crops that I have defended) in the US, Australia, Canada, or Europe. Corn must be used carefully or not at all in some areas of Mexico, potatoes in some areas of the Andean region, etc. Thus I have not recommended "unsafe sex".

With respect to canola, the crop is being sprayed with herbicide anyway, so Barton was correct. If the weeds became resistant to his herbicide Round-up, you could always spray with whatever is being used now. In Australia, canola is grown on 1 million hectares where it is sprayed with 1-2 kg of atrazine per hectare. Atrazine is a noted water contaminant. My vision of the world would be to use something less polluting for control of weeds in canola, even if it only buys a few years toward more durable solutions. I am not so blinded by religious or philosophical views that I will not consider a GE crop to do that. Further, since there is no GE protein or DNA in canola oil (as for cotton), I don't see any possibility of a health threat.

With respect to insect resistance, as I said here last week, insects evolve resistance in short periods even to Bt sprays. In the case of diamondback moth, my experimental work has shown that Bt transgenic crops can actually make Bt last longer than if Bt used as sprays (see citation below). Would you force everyone to use Bt sprays even if it causes Bt to fail sooner?


Roush, R. T. 1997. Managing Risk of Resistance in Pests to Insect-Tolerant Transgenic Crops pp. 259-271 in G. D. McLean, P. M. Waterhouse, G. Evans, and M. J. Gibbs (eds) Commercialisation of Transgenic Crops: Risk, Benefit and Trade Considerations. Proceedings of a workshop, Canberra, 11-13 March 1997. Cooperative Research Centre for Plant Science and Bureau of Statistics, Canberra