adwright at adwright at
Fri Sep 11 13:57:10 EST 1992

In <1992Sep11.162916.3759 at> browns at (Stuart Brown) writes:

>I found Steve Modena's discourse on Information-Based Farming quite interesting.
>However, I do not think that this type of pragmatic "forget the philosophy, its
>a high-tech competitive world out there" approach adequately addresses the very
>real issues raised by Ricardo.  

>I am "just" a Plant Molecular Biologist, so I don't have a lot of professional
>standing from which to pontificate on Agro-informatics or the Social Justice
>aspects of Agricultural Economics, but I do think about these things quite a

>For example, some of the first genetically engineered plants that will
>become commercially available will be herbicide resistant varieties.  This is
>clearly a contentious issue between the pragmatists and the Social Justice
>types. These resistant varietites will be sold at a premium price in a package
>with the herbicide that they resist.  The net effect will be a slight increase
>in yield with a higher net input cost (big research dollars must be recovered
>from profits).  Very large scale farmers will achieve some benefit from the
>economy of scale while smaller farmers will either benefit less from the input
>to yield ratio, or else forgo the yield increase and avoid the engineered seed.

>The net result of applying this new technology to agriculture will be a slight
>yield increase and a greater consolidation of agricultural production.  I also
>have some worries about the long term ecological soundness of this strategy.
>First, resistance to the herbicide will develop in weed species at a rate 
>proportional to the acreage sprayed with the herbicide.  Second, there may be
>an incentive to use higher herbicide doses when planting a known resitant crop
>variety - also less worries about carryover in the soil.

I wonder about that. If we can spray with impunity our resistant corn, we could
wait till the corn (and weeds) are up and then spray . I am not a weed
 scientist but i would think under such conditions we could use less herbicide
as well as one that "breaks down" more quickly. I think being able to forget
about preemergence spraying would bee a real benefit. 

 Third, since the 
>genetic engineering necessary to produce resistant crop varieties is costly,
>only one (or a very few) varieties of a given crop are likely to be produced
>with this resistance, so if this is widely accepted, then the germplasm base
>present in the fields will be very narrow.  Huge acreage planted to a single 
>variety is an ideal situation for a disease epidemic.

Resistant varieties can be backcrossed into other varieties in a few 
generations with marker-assisted selection. 

Resistance has been produced by simple induced mutation of corn, a relatively 
easy and cheap thing to do. Suicide screening would be easy and you can find
your resistant variety in less than 100,000 M2 Families.(if you did even a half
way decent job of inducing mutation). I do not know how (biochemically) these
 resistant lines deal with the herbicide but a possibility is that one of
  glucosyltransferase enzymes gets less "fussy" about its substrates and takes
on the herbicide too. 

>Anyway, I'd like to see new tecnologies of genetics and information sciences 
>used to stabilize agriculture and help small farmers at least as much as large
>ones. Perhaps you economists and theorists can come up with some ways that 
>these technologies can be used to increase profits by lowering input costs
>rather than raising them.  And perhaps we need to think of ways to fund
>agricultural research that do not require huge profits to be made from the sale
>of farm inputs in order to recover development costs.

>I'm personally interested in engineering disease and insect resistance in 
>order to reduce pesticde use and increse the stability of yield - but I do worry
>that these engineered plants will be sold as high cost inputs and contain a
>narrow gentic base.

>I like the idea of using bionet for these deeper debates, rather than always
>focusing on narrow methodological questions.  Which is not to say that the
>facutal question/answer function is not valuable too.  Its just that I've been
>at so many seminars where all of the questions were about "How?" and no one
>ever asked "Why?" or Where will this lead?"

>	Cheers  -Stu

>Stuart M. Brown                             If you can remain cool when all 
>U. of Manitoba, Dept. Plant Science         Around you are in panic,
>Winnipeg, Manitoba, CANADA
>browns at            Then you surely misunderstand the situation

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