5 - 



A 



UJ 



>- 



Q 



a: 

 d 



I- 

 o 

 < 



o 

 u. 

 o 



LU 

 Q. 



cn 



TOTAL 



J. 



4 



ROOT IMMERSION 



0.5 - 



2 3 4 



LEAF AGE, POSITION 



2 4 7 



GROWTH STAGE, NUMBER OF LEAVES 



Fig. 2. A. Radioactivity in cotton leaves after absorption by roots immersed to 

 different depths. B. Influence of leaf age on ethylene-C" fixation in cotton. C. Ab- 

 sorption of ethylene-C" by leaves and stems of cotton plants at three growth stages 

 from yoimg vegetative (2-leaf) to young fruiting (7-leaf). 



