Dehydrogenase activity and microbial population in a red sandy soil amended and unamended with incubation.

Incubation of single bulk sample of freshly collected red sandy soil in trays showed immediate response to added nutrients both in dehydrogenase activity and bacterial and fungal populations. The prevailing acidic pH might have been responsible for the observed response of fungi as well. Actinomycetes population did not fluctuate. It was therefore suggested that TTC dehydrogenase technique for measuring the biological activity could be applicable to coarse-textured and more open soils. There were indications that fungi contributed to the soil dehydrogenase activity as well.