Panel:
Ramon Georgis, biosys
Bill McCutchen & Lindsey Flexner, DuPont
Sinthya Penn, Beneficial Insectary
Steven Sims, Monsanto
(prepared from the videotaped session*)
Question: Natural enemies have the desirable properties of 1) killing pests, and 2) reproducing to make more natural enemies. My concern is that the commercialization process, especially of viruses, is compromising the ability of the natural enemies to reproduce. A major reason for this, we are told, is because the wild-type virus doesn't kill pests quickly enough. The recombinant viruses act more quickly, but they don't persist in the field. We've heard from Brazil and other places that epizootics can be easily created, that single sprays of natural viruses can control pests for a whole season via their ability to reproduce, yet we are impairing these natural enemies' abilities to reproduce. We wouldn't think of doing this to predators or parasitoids. It would seem the speed of kill issue is driven by growers' demands, yet I've never heard this expressed.
Also, it seems that by removing the ability to reproduce, biotechnology firms are acquiring ownership of the natural enemies which improves their ability to hold the market and also requires the farmer to buy over and over again which increases sales. It seems the companies are using tunnel vision based on their 40 years of experience in the marketplace when they should be looking at innovative ways of approaching problems.
Bill McCutchen: Your assertion that the recombinant viruses' ability to reproduce is vastly diminished is correct. According to studies we have done, some of our recombinant viruses produce an order of magnitude less occlusion bodies compared to the wild-type virus, so the capacity of the recombinant virus to continue to produce secondary outbreaks is vastly diminished. Also, in competition with the wild-type virus in the field, the transgenic virus is at a clear disadvantage. However, the growers are very demanding and their expectations are very high. They are accustomed to spending $5 to 6$ per acre for pyrethroids, which, in 24-48 hours, deliver a mortality rate of approximately 95%. If we don't offer them quick control, the growers won't change from classical chemicals, especially in large, monoculture settings.
Ramon Georgis: I believe there is a market for both recombinant and wild-type baculoviruses from a marketing point of view. There are two wide host range baculoviruses that are easy to work with and have good potential for being produced by fermentation. But many baculoviruses that are difficult to work with still work well in the field and there is much potential for these to be improved through such techniques as formulation stability, application techniques, and proper introduction into an IPM program. I don't think the companies are making the recombinant viruses less vital reproductively in order to increase sales because even with the common wild-type viruses, reapplication is necessary due to population decline to the point where the pests aren't controlled. A well developed wild-type virus could have great potential. The bottom line is the margin that big companies and small companies, too, are looking for.
Flexner: This question is raising a different angle on this issue. What regulatory organizations are worried about is that the recombinant virus may out-compete the wild-type virus and expand its host range. There are several methods that one could use to prevent this. One approach has been to cripple this virus (eg. trying to incorporate suicide mechanisms as a safeguard to make sure the organisms can't reproduce). The epidemiology and epizoology of these organisms have been poorly studied compared to the volumes of efficacy data that have been generated over the last 25 years.
Thus, we feel much more comfortable putting something out in the field that we know is at a selective disadvantage compared to the wild-type virus. I think that as we go forward in genetically engineering microbials we need to do this in a very safe and responsible way. That means a lot of safeguards and testing. I think that's been the approach of American Cyanimid, of DuPont, and of Monsanto.
Question: I am interested in the resistance management strategy (RMS) proposed for Bt cotton plants. If you were to implement this, would it be mandatory? What about a system where there are small-scale farmers or even medium-scale farmers who might not be able to sign up with the RMS? How would the RMS's be applied in underdeveloped tropical ecosystems where pest dynamics would probably be quite different than here? Cotton is a very important crop outside of the US, so there must be some way to address these issues on an international basis.
Steve Sims: We don't know. Each country would have to be responsible for developing its own RMS through its seed company organizations or grower groups for appropriate climate and growing conditions and pests. The size and type of refugia might be changed. So far it has not been worked out because the plants haven't gotten there, yet. For example, China will have to make its own decisions, regulations, etc. We can only suggest and advise. It will be interesting to see how they do this.
Here we require, as part of our licensing, the growers to set aside a certain portion for refugia - either 4% non-treated/non-Bt plants, or 20% treated, but not with Bt - and they must agree to one of these two strategies.
Question: I've read that Monsanto is considering requiring a technology fee of the growers. How can they justify such a fee when they are also requiring that 4% or 20% of the grower's crop be set aside as a refugia?
Steve Sims: Our policy is based on how the plants are sold. Growers buy the product from distributors. They sign an agreement that says they will pay for biotechnology by the acre. They are not buying a sack of seed. The current price is a $32 per acre license fee. That is very attractive in parts of the country where bollworm and budworm are serious problems and growers would spend much more on control. In other parts of the country, such as Texas, that price is not so attractive. The license fee commits the growers to buy into system management in general and a refuge in particular. We set the two numbers, 4% and 20%, at levels where our studies showed the yield to be not lower than with traditionally managed fields.
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