Journal of Agricultural Research 



Vol. XII. No. 4 



p. 187) were employed and conditions governing the preparation and 

 incubation of the cultures were similar in the case of each strain. The 

 only variation was the periods used in incubating the cultures. Counts 

 were made after one and two weeks' incubation with strain A and after 

 one, two, and three weeks with strain B. 



Table I. 



-Influence of potassuim nitrate on the growth of Azotohacter {strain A) in 

 sterilized soil 



Table II. — Influence of sodium nitrate on the growth of Azotobacter {strain A) in 



sterilized soil 



