fungicide, what the major and auxilliary bio- 
chemical processes are in the major plant 
pathogens, how avirus operates biochemically, 
what makes a fungus obligately parasitic or 
what forces of microbial competition operate 
against plant pathogens in the soil, and what 
the genetic code for disease resistance must 
be. If we knew these things, molecules could 
be designed to meet the practical demands of 
agriculture, Possibly molecules would be de- 
veloped that could be more selective in their 
action, less persistent in the environment, and 
less suspect of hazard to man, domestic ani- 
mals, or the environment. The opportunities 
for service lying ahead are exhilarating, but 
they will be realized only by acquiring the basic 
knowledge outlined above, and much more, to 
guide the research effort that is needed. 
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