41 6 MICROBIOLOGY OF SOIL 



physical or chemical condition of the soil itself. The principle of using 

 artificial cultures to be applied with the seed is sound, and if the cul- 

 tures contain large numbers of virile bacteria, there is little reason 

 why they should not prove of benefit when used under soil conditions 

 that would seem to need inoculation. 



Azotobacter Cultures. Some experimental work has been done in 

 the use of cultures of Azotobacter for soil inoculation. The results are 

 contradictory, and more work needs to be done to prove the value 

 of such cultures. 



