266 



Mineral Nutrition of Plants 



2000- 



1750- 



1500- 



o 

 E 



4> 



C 

 3 



o 

 o 



1250- 



1000- 



7 50 



CM 



°- 500- 



250- 



12 3 4 5 6 



Position of Leoves on stem ( base : tip = left irighP 



Figure i. The amount of radiophosphorus acquired plotted against the 

 position of the leaves on the stem for ten bean plants grown in the same 

 nutrient tank. Oldest (opposite) leaves on extreme left; youngest leaves 

 on right. 



