44 



BOTANICAL GAZETTE 



[JULY 



well as again showing the influence of the potassium fertilizers as 

 above described. In this experiment the green weight in the 



normal 



The 



results for the mainly phosphatic, mainly nitrogenous, and mainly 

 potassic fertilizers are 76, 77, and 85, respectively, again showing 

 the relative greater efficiency of the potash fertilizers in this 

 quinone experiment. 



These quinone experiments indicate clearly the harmful influence 

 of quinone on growth, and the effect of potassium in counteracting 

 this action of the quinone. In the second experiment the cultures 

 were analyzed for phosphate, nitrate, and potassium, and it is, 

 therefore, interesting to inspect these data, as was done with the 

 cumarin results. Only the 36 cultures having the combinations 

 of all three fertilizer salts are considered. 



The amount of total P 2 5 +NH 3 +K 2 removed from solution 

 by the growing plants in the total number of 36 cultures was 1568 

 milligrams in the normal set and 1327 milligrams in the quinone 

 set, showing a decrease in the sum total of P 2 s , NH 3 , and K 2 

 removed when auinone is oresent. 



In table III are given the 



results for the P 2 O s , NH 3 , and K a 

 conditions and in the quinone set. 



TABLE III 



« 



Total milligrams of p 2 o s , nh 3 , and k 2 o removed from the 36 culture solutions 



containing all three of these ingredients 





Total absorption in milligrams 



Normal 



PA 



NH 3 

 K,0 



300 



S7i 

 696 



•4 

 ■5 

 •5 



Quinone 



173-6 

 506.8 



646.5 



Relative 



58 



93 



Percentage of 



quinone cultures 



above normal 



8 

 II 



36 



An inspection of these figu 



more normal 



than the other two nutrient elements. 



shown 



relative absorption in the 

 quinone cultures showing 

 NIL, and K 2 0, respectively, in the last column 



column and bv the number 



normal 



