Environmental Influences on Microbial Growth

The rate of growth or death of a particular microbial species is influenced by a variety of physical factors in its environment including temperature, osmotic pressure, pH, and oxygen concentration.  In nature, where many species coexist, fluctuating environmental conditions cause dramatic population shifts due to the varying growth rates of different microorganisms.  Every microbial species has a set of optimal conditions under which it flourishes.  However, because the conditions in natural environments fluctuate widely, microbes have adapted tolerance to a range of environmental conditions.  For example, many microbes have an optimum growth temperature of 30°C, but will still grow, albeit slower, at 4°C.  In the laboratory, where conditions can be controlled, it is possible to achieve optimal growth conditions for a given microorganism. 

• Temperature
• Osmotic Pressure
• pH
• Oxygen Concentration

Rachel Watson, M.S.
AG 5010
766-3524
Cell: 307-760-2942
rwatson@uwyo.edu