GENTECH archive


Re: Rachel #63, archive 747

Have you sent your comments to Peter Montague for his consideration?
Clive Elwell
-----Original Message-----
From: Rick Roush <>
To: <>
Cc: <>
Date: Thursday, 18 February 1999 01:09
Subject: Re: Rachel #63, archive 747

>From .
>. ---February 11, 1999--- .
>. ==========

Among the many comments in this article that are misleading or just plain wrong, the following stand out and require commment.

> The
>new genetically engineered seeds require high-quality soils,
>enormous investment in machinery, and increased use of

Blatantly wrong. The key genes have been introduced into widely used current varieties and require no more special treatment than do the traditional versions of the same varieties. In fact, the insect resistant crops require much less chemical.

>There is evidence that their per-acre yields are
>about 10% lower than traditional varieties (at least in the case
>of soybeans),[1,pg.84] ..

Also wrong, the clearest evidence of which is that growers are so happy with yields that they are planting even more land to the crops.

>The plain fact is that fully two-thirds of the genetically
>engineered crops now available, or in development, are designed
>specifically to increase the sale of pesticides produced by the
>companies that are selling the genetically engineered

Perhaps true but certainly misleading. The farmers may be using more of Monsanto's herbicide but they are using a lot less of the competition's pesticides, which are generally more persistent.

>Monsanto's other major line of genetically engineered crops
>contains the gene from a natural pesticide called Bt.... Farmers who try to
>minimize their use of synthetic chemical pesticides rely on an
>occasional dusting with Bt to prevent a crop from being overrun
>with leaf-eating caterpillars....

Resistance has already evolved to Bt in the diamondback moth in at least 10 countries. Far from "an occasional dusting", Bt is used as often as 3 times a week. Resistance occurred in as little as 4 years. While I was in New York, potato growers used Bt up to 6 times a season.

We have already demonstrated that transgenic crops can actually make Bt last longer than Bt sprays:

Roush, R.T. 1994. Managing pests and their resistance to Bacillus thuringiensis: Can transgenic crops be better than sprays? Biocontrol Sci. Technol. 4, 501-516.

Shelton, A. M., Tang, J. D., Roush, R. T. and Earle, E. D. 1998. Can we manage resistance to Bt-engineered plants? Results of greenhouse and field tests. Proceedings of the Sixth Australian Applied Entomological Research Conference, Brisbane, Australia, October 1998. pp. 258-266.