Consequently, the application by CMC... to field test recombinant DNA plants 
should be transferred to Agracetus, and all information previously submitted by 
CMC in support of its attempt to get approval for such field testing should be used 
to obtain approval for Agracetus." 
Agracetus has used a modified T-DNA from Agrobacterium tumefaciens to induce, 
in tobacco, resistance to crown gall disease. They have examined, in greenhouses 
and growth chambers, over one thousand genetically engineered tobacco plants 
spanning five generations and did not observe any changes that would indicate that 
the proposed field test poses any significant risk to health or the environment. 
When the T-DNA of A. tumefaciens is made avirulent by insertional mutation of 
the T-DNA cytokinin gene, tobacco plants containing this modified T-DNA are 
significantly more resistant to crown gall disease than those plants not genetically 
engineered. The genetically engineered plants are no different in growth rate, 
seed yield, growth habits, etc., than control tobacco plants without the modified 
T-DNA. So far, these tests have all been performed in greenhouses and growth 
chambers. There are, however, many examples of plant phenotypes expressed 
under field conditions that are not expressed in greenhouses. Field conditions 
have stresses that are not encountered in greenhouses; for example, water 
scarcity, water excess, temperature fluctuations, etc. For these reasons, 
Agracetus would like to field test these genetically engineered tobacco plants to 
be sure that incorporation of the modified T-DNA into plants does not debilitate 
them in some unexpected way. 
Environmental Assessment 
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