Comparatively few data have been recorded relative to the effect of hydrogen ion concentration on the development and activities of molds and other fungi, altho such records have been secured for the bacteria. For both groups much more work has been accomplished on the effect of titratable acidity. The importance of molds in transforming plant food in the soil has made advisable the securing of such data. The present paper records the results of a study of the limiting and optimum hydrogen and hydroxyl ion concentrations and the limiting concentrations of several salts as related to the growth of seven different molds isolated from the soil.
Johnson, Harlan W.
"Relationships between hydrogen ion, hydroxyl ion and salt concentrations and the growth of seven soil molds,"
Research Bulletin (Iowa Agriculture and Home Economics Experiment Station): Vol. 5
, Article 1.
Available at: https://lib.dr.iastate.edu/researchbulletin/vol5/iss76/1