/l/ Refers to the ratio of the volume of COg released to the volume of Og absorbed. /2/ Data 

 applicable to root slices. /5/ At 0° C, 2.5; at U.50 c, U.J. /h/ At 0° C, 2; at U.50 c, 3.3; 

 at 15.5° C, 8.6. /5/ At 250 c, 56-U3. /6/ Value applicable to primary root tip, 3 days after 

 germination. For adventitious root portions (root tips not included), 2 weeks after germina- 

 tion, 82. /7/ At U. 50 c, 2-5. /8/ At 0° C, 0.2; at U. 50 c, 1.3. /9/ Value applicable to 

 root tip. For rootlet. In growth zone, 1,200; for rootlet, in root hair zone, 3OI-625. /lO/ 

 At 150 c, 2-3. /ll/ Immature tuber at 20O c, I6.8. /l2/ At 0° C, 2.0; at 10° C, h. /15/ 

 At 250 C, 9 cu mm O2 absorbed. 



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