Table IV. Cell density of an inoculum grown in microtubes fixed at the bottom of flasks containing BG11 fresh medium (control) or a culture that had reached stationary phase (treatment).

Cell number (cell number mL⁻¹) is shown for urea cultures grown under 50 µmol photons m⁻² s⁻¹ (ML) and 200 µmol photons m⁻² s⁻¹ (HL). Values represent means ± sd (n = 3). Asterisks represent significant differences between means for the same growth condition (P < 0.05, paired Student’s t test).

Condition	ML			HL
	Day 0	Day 4	Ratio (Day 4:Day 0)	Day 0	Day 4	Ratio (Day 4:Day 0)
Control	5.69 × 106 ± 7.63 × 105	4.31 × 107 ± 6.07 × 106*	7.58 ± 0.39	3.40 × 106 ± 8.61 × 105	3.81 × 107 ± 1.36 × 107*	11.00 ± 1.23
Treatment	5.23 × 106 ± 8.19 × 105	2.43 × 107 ± 2.86 × 106*	4.67 ± 0.33	3.12 × 106 ± 2.89 × 105	3.40 × 107 ± 7.90 × 106*	10.83 ± 1.62