Antitoxic Action of Certain Bases 



137 



TABLE 2. Series 1. Experiment with Canada Field 



Pea. Duration, Thirty Days- 







Data for 



Ten Plants 







Composition of 



Green 



weight 

 of 



tops 

 (grams) 



Green 



weight 



Total 



Average 

 length 



Average 

 length 







solution 

 (nutrient solution 



of 



roots 



(grams) 



green 

 weight 



of 

 tops 



of 



roots 



Color of tops 



Remarks 



as the solvent) 



(grams) 



(centi- 

 meters) 



(centi- 

 meters) 







N/25 CaCl2 + 















Lateral roots good 



N/50 IMgCl2. . . . 



12.85 



9.00 



21.85 



20 



14 



Light at tips 



length 



N/25 CaCl2 + 















Lateral roots good 



N/100 MgCl2... 



14.15 



8.25 



22.40 



20 



12 



Light at tips 



length 



N/25 CaCl2 + 















Lateral roots good 



N/200 MgCb. . . 



14.30 



8.85 



23.15 



19 



12 



Good 



length 



N/100 CaCl2 + 















Lateral roots medium 



N/100 MgCl2. . . 



10.25 



6.50 



16.75 



14 



12 



Good 



length 



N/500 CaCl2 + 

















N/100 MgCb. . . 



8.45 



4.60 



13.05 



12 



10 



Good 



Lateral roots fair 



N/1,000 CaCl2 + 

















N/100 MgCl2. . . 



10.70 



5,60 



16.30 



15 



14 



Good 



Lateral roots short 



N/50 MgCl2 



10.55 



5.90 



16.45 



15 



12 



Good 



Lateral roots short 



N/100 MgCb 



9.65 



5.50 



15.15 



14 



11 



Good 



Lateral roots medium 



N/200 MgCl2 



10.40 



5.70 



16.10 



11 



9 



Good 



Lateral roots medium 



N/25CaCl2 



11.85 



6.65 



18.50 



20 



14 



Pale green 



Lateral roots medium 



N/100 CaCl2 



13.50 



7.90 



21.40 



17 



9 



Light green 



Lateral roots good 



Nutrient solution. 



10.40 



5.20 



15.60 



13 



10 



Good 



Lateral roots fair 



Toxic strengths of magnesium were used in these experiments. It 

 is to be noted that in this nutrient solution N/10 MgCl2 prevents 

 growth of roots, and solutions of N/50 are injurious. The leaves of 

 the plants grown in solutions of N/10 CaCl2 are pale green in color, 

 and those in N/100 CaCl2 are sorriewhat lighter than in the control 

 cultures. 



The toxicity of N/10 MgCl2 (Table 3) is greatly reduced, although 

 not entirely prevented, by the same concentration of calcium chlorid. 

 It is also to be noted that the harmful action of either N/20 or N/50 

 MgCl2 is completely counteracted by solutions of N/10 CaCl2. No injury 

 results from the magnesium in cultures composed of this nutrient solu- 

 tion + N/100 CaCls + N/50 MgCla. 



In this series of experiments the addition of magnesium to the solutions 

 of calcium has not resulted in an appreciable increase in the gro"wth of the 

 plants. It is to be observed, however, that the chlorotic condition induced 

 by the calcium is prevented by the magnesium. A summary of the data 

 obtained appears in Table 3. 



