Facilitation as Attenuating of Environmental Stress among Structured Microbial Populations

Table 1

Fitness index of Serratia marcescens and Candida rugosa under the effect of different phenol concentrations.

Phenol (mg L^−1)	Fitness index (FI)
	Serratia marcescens	Candida rugosa
62.5	1.65	0.96
125.0	1.45	1.70
250.0	2.10	3.00
500.0	2.00	3.20
1000.0	Indefinite	Indefinite

Positive interactions FI > 1, negative interactions FI < 1, and neutral interactions FI = 0.
The fitness index (FI) is the ratio of the exponential growth rates of each microbial strain in different phenol concentrations, in consortium and as individual culture.