The Struggle for Existence: Competition Between Bacterial Strains

 

Beth A. D. Nichols, Linda B. Cholewiak, and Richard Condit

Tested Studies in Laboratory Teaching, 1992, Volume 13

Abstract

Two strains of Escherichia coli are grown in broth and plated out at intervals. A population growth curve is plotted for each strain. The two strains are then grown together for several days in different types of broth. Students from each day’s laboratory plate out the mixed culture on selective media. Data are pooled. Population curves are plotted for the two strains in competition. With different conditions, it is possible to observe competitive displacement of one strain by another.

Keywords:  bacteria, E. coli, competition, carrying capacity, lag phase, exponential growth

University of Wyoming, Laramie (1991)