NUTRIENT REQUIREMENT OF THE POTATO 



335 



The size of the plants was far below normal and their color, 

 in general, was a light green or yellow. At the end of the experi- 

 ment the roots were much discolored and in several cases had 

 rotted off. It is evident that normal healthy plants can not be 

 grown by this method. There was, however, some growth as is 

 shown by the increase in green weight. Three sprouts similar 

 in size and appearance to those placed in the solutions were dried 

 and weighed at the beginning of the experiment. Their dry 

 weights were 0.56, 0.64 and 0.62 gram, giving an average of 0.61 



TABLE 1 



* Two plants in average, 

 t One plant in average. 



gram. When the dry weights as given in the table are compared 

 with this average initial dry weight there is further evidence of 

 growth. The plants of the cultures R1S6 and R2S4, where the 

 total osmotic pressure is mostly due to calcium nitrate, seem to 

 have grown best as indicated by percentages of increase in green 

 weight and by their greatest total dry weights. These plants 

 also usually transpired more than the others. Three plants 

 grown in distilled water died before the end of the period. 



CONCLUSIONS 



The growing of cuttings from potato vines was an unsatisfac- 

 tory method of obtaining uniform potato plants. 



Normal potato plants were not produced either in good gar- 

 den soil or in nutrient solutions from sprouts separated at an 

 early developmental stage from their tubers. 



