TABLE 2.

Effects of different nitrogen sources on growth rates and CYL concentrations (measured at the end of the period of exponential growth) of seven C. raciborskii isolates in pure cultures

Isolate	Value obtained with N source:
	No nitrogen addition		NO3−		NH4+
	GRa	CYLb	GRa	CYLb	GRa	CYLb
CR1	0.63 ± 0.05 (4)	0.46	0.65 ± 0.05 (4)	0.35	0.83 ± 0.16 (3)	0.23
CR2	0.75 ± 0.16 (4)	0.30	0.93 ± 0.01 (3)	0.27	1.05 ± 0.01 (3)	0.21
CR3	0.65 ± 0.09 (4)	0.38	0.69 ± 0.12 (3)	0.42	0.51 ± 0.03 (3)	0.34
CR4	0.77 ± 0.13 (4)	2.9 × 10−2	0.64 ± 0.3 (3)	2.8 × 10−2	1.30 ± 0.18 (3)	2.1 × 10−2
CR5	0.87 ± 0.31 (3)	1.2 × 10−4	1.41 ± 0.27 (3)	7.0 × 10−5	1.44 ± 0.31 (3)	NDc
CR6	0.89 ± 0.15 (3)	ND	1.20 ± 0.14 (3)	ND	1.49 ± 0.29 (3)	ND
CR7	0.86 ± 0.06 (4)	ND	0.71 ± 0.10 (4)	ND	1.10 ± 0.31 (3)	ND

^aGrowth rate in divisions day⁻¹ ± 1 of standard deviation. Values in parentheses are numbers of replicates. 

^bPercentage of freeze-dried weight. 

^cND, not detected.