Improvement of Growth Regulator Formulation 801 



should continue to do so. The conscious design of more effective 

 plant growth regulators for agricultural use is an ever present chal- 

 lenge to jDCsticide workers and biochemists. 



ACKNOWLEDGMENT 



Much of the work reported here was supported by A.E.C. Con- 

 tract AT(ll-l)-34 Project No. 9 and Project No. 38. 



LITERATURE CITED 



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DISCUSSION 



Dr. Henderson: What form of 2,4-D was used and where was the 

 label? Do you believe that 2,4-D does not enter as the whole molecule? 



Dr. Crafts: We used 2,4-D acid, labeled in the carboxyl position. 

 We're convinced that with this compound the bulk of the labeling 

 in our autograms is 2,4-D. With maleic hydrazide, and some of the 

 substituted benzoic acids we're fairly certain that these molecules are 

 stable enough that our autograms show the distribution of the orig- 



