Since the isolation of species of Azotobacter by Beijerinck in 1901, many investigations have been conducted to determine the mineral requirements of the organisms of this genus. In most of this work it has been found that increasing concentrations of phosphates up to a certain limit, greatly stimulate the growth of Azotobacter. The question may be asked-- are the rather large amounts of phosphorus which seem to be necessary for maximum growth assimilated by the organisms or do they serve another purpose, such as a stimulant or a buffer in the culture medium?
Proceedings of the Iowa Academy of Science
©1931 Iowa Academy of Science, Inc.
Thompson, L. G. Jr. and Smith, F. B.
"The Effect of Phosphorus on Nitrogen Fixation by Azotobacter,"
Proceedings of the Iowa Academy of Science, 38(1), 299-302.
Available at: https://scholarworks.uni.edu/pias/vol38/iss1/107