Bt resistance

[Lorine S Horvath]

	I would have to agree with the idea that there would be some 
eveolution of insects to Bt (even the really strong ones).  However,
it may be possible to allow the plants to evolve as well.  Recent 
findings point to many disease resistance genes being clustered.  It 
has been proposed that this allows them to undergo recombination with 
members of the gene family that then could lead to new specificities and 
resistances.  Would it not be possible to engineer a plant(s) with 
a cluster of a dozen or so Bt genes with different specificities and under 
different promoters, develop a population from these engineered 
plants and turn them over to the breeders?  This way, as the insects 
evolved, the breeders may be able to identify individual plants/families 
that have enhanced resistance (due to recombination of the various Bt 
genes) to whatever insect that are the problem.  Just a thought!

Dave Horvath
USDA/ARS/NCSL
Fargo, ND 58105