Table II.

Elongation rates of sorghum cvs 58 M (phyB-1) and 100 M (PHYB) grown under different photo/thermoperiod regimens

Cultivar and Illumination	12/12 Photo-Thermoperiod Elongation Rate	12/12 Dim Incandescent Photo-Thermoperiod Elongation Rate	12/12 Reversed Photo-Thermoperiod Elongation Rate
		mm h−1
58 M-light period	1.90  ± 0.07 (n = 21)	2.09  ± 0.08 (n = 15)	0.99  ± 0.04 (n = 13)
100 M-light period	1.58  ± 0.06 (n = 20)	2.01  ± 0.05 (n = 15)	0.61  ± 0.03 (n = 15)
58 M-dark period	0.94  ± 0.04 (n = 21)	0.93  ± 0.04 (n = 15)	1.56  ± 0.04 (n = 13)
100 M-dark period	0.58  ± 0.04 (n = 20)	0.76  ± 0.03 (n = 15)	0.81  ± 0.04 (n = 15)

Rates were calculated over 12-h periods, beginning 6 d after sowing, from growth curve data presented in Figure 6. Values are means ± se.