Figure 2.

Growth of various cyanobacterial strains in competition with each other in batch cultures. Pairs of strains were mixed together and an aliquot was plated to form single colonies to determine the initial composition of the culture. The strains were grown for 27 days in batch culture under either a 22-h LD cycle (LD 11:11) or a 30-h LD cycle (LD 15:15), and then another aliquot of the mixed culture was plated to determine the 27-day composition of the culture. Each horizontal sequence shows the results for the pairs of strains listed on the right. The composition of the cultures was determined by observing the luminescence patterns of the colonies and counting the number of colonies on each plate exhibiting each of the strain-specific phenotypes by using a CCD camera/turntable apparatus (13). In the experiments depicted in this figure, wild type was strain AMC149. The experiment was repeated three times with essentially the same outcomes.