EVALUATION OF DEHYDROGENASE AS A SUITABLE INDICATOR OF SOIL MICROFLORA ACTIVITY

Dehydrogenase activity was determined in a variety of soil samples to assess the assay's suitability as an indicator of soil microorganism activity. This technique, like others in soil ecology, has shortcomings. The work outlined below demonstrates that the dehydrogenase assay can provide a valid indication of soil microorganism activity. Although dehydrogenase activity can be correlated with the numbers of microorganisms isolated, the application of herbicides, which are not greatly toxic to microorganisms, results in a reduction in dehydrogenase activity but little alteration in the number of microorganisms isolated. As this reduction can be accounted for, the use of the assay could be advocated in determining soil microbial activity in ecological investigations. © 1979.