Microbial Growth Rate in Glucose‐Amended Soil

Microbial growth in soil amended with glucose was evaluated. Following the incorporation of glucose into soil, rapid evolution of CO 2 occurred and was accompanied by a similar increase in bacterial numbers. It appeared that the amendment was utilized primarily by bacteria and was wholly expended within the first 2 days of incubation. Subsequently fungal growth was noted at the time the bacterial count declined. The developing bacterial population followed the typical sigmoid growth curve and a minimum generation time of 2 hours was obtained during the period 5 to 10 hours after adding the glucose. It was determined that the yield coefficient of bacteria produced relative to substrate consumed was 0.39 g of cell C/g substrate C. The energy expended by the population for functions other than production of new cell material, referred to as specific maintenance, was estimated to be 0.0036 hour ‐1 .