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DISCUSSION 



Dr. Waygood: I'd like to point out that there is no inhibitory 

 effect of gibberellin on a purified lAA oxidase system. The effect of 

 lAA and gibberellin shown in the slide by Brian and Hennning is 

 not a synergistic effect. 



Dr. Housley: Our results do not conflict with Dr. Waygood's first 

 statement that there is no inhibitory effect of gibberellic acid on a 

 pmificd lAA oxidase system. With respect to his second statement, 

 perhaps the use of the term synergistic in the present context is best 

 left for each individual worker to accept or substitute otherwise ac- 

 cording to preference. 



