Supplementary Tables for

Fitting Light Saturation Curves Measured Using Modulation Fluorometry

by Raymond J. RITCHIE, School of Biological Sciences, The University of Sydney, NSW 2006, Australia, Revised Date: 23 March 2008

Supplementary Table 1: Comparison of the Light saturation curve parameters fitted to ETR vs. irradiance using the Waiting-in-Line, Michaelis-Menten, Exponential saturation and hyperbolic tangent models for Prochlorothrix. The Waiting-in-Line model in Table 3 utilised the full data set up to 351 µmol m-2 s-1 PAR but since the optimum irradiance was found to be at about 80 µmol m-2 s-1 PAR the ETR measurements at irradiances above 91 µmol m-2 s-1 PAR were omitted from use in fitting the curves.

Waiting-in-Line Model / Michaelis-Menten Model / Exponential Saturation Model / Hyperbolic Tangent
k / 0.0136 ± 0.000941 / 25.9 ± 3.04 / 0.0404
± 0.00561 / 0.0316
± 0.00310
Maximum Photosynthesis (Pmax) / 337 ± 20.3
(ETR µmol mg Chl a-1 h-1)
84.3 ± 5.08
(µmol O2 mg Chl a-1 h-1) / 448 ± 18.3
(ETR µmol mg Chl a-1 h-1)
112 ± 4.58
(µmol O2 mg Chl a-1 h-1) / 350 ± 17.3
(ETR µmol mg Chl a-1 h-1)
87.5 ± 4.33
(µmol O2 mg Chl a-1 h-1) / 338 ± 12.6
(ETR µmol mg Chl a-1 h-1)
84.5 ± 3.15
(µmol O2 mg Chl a-1 h-1)
Optimum light
(µmol m-2 s-1) / 73.3 ± 5.05 / NA / NA / NA
1/2 Optimum Light
(µmol m-2 s-1) / 17.0 ± 1.17 / 25.9 ± 3.04 / 17.2 ± 2.38 / 17.4 ± 1.71
Inflection Irradiance
(µmol m-2 s-1) / 147 ± 10.1 / NA / NA / NA
Photosynthetic Efficiency ( Alpha, ), / ETR = 347 ± 31.8 (x 10-6 m2 mg Chl a-1)
O2 = 86.8 ± 7.95 (x 10-6 m2 mg Chl a-1) / ETR = 480 ± 59.7 (x 10-6 m2 mg Chl a-1)
O2 = 120 ± 14.9 (x 10-6 m2 mg Chl a-1) / ETR = 393 ± 66.2 (x 10-6 m2 mg Chl a-1)
O2 = 98.2 ± 16.6 (x 10-6 m2 mg Chl a-1) / ETR = 297 ± 31.2 (x 10-6 m2 mg Chl a-1)
O2 = 74.3 ± 7.80 (x 10-6 m2 mg Chl a-1)
Correlation r (number of samples, data points) / 0.9845
(9,54) / 0.9736
(9,54) / 0.9796
(9,54) / 0.9827
(9,54)

Supplementary Table 2: Comparison of the Light saturation curve parameters fitted to ETR vs. irradiance using the Waiting-in-Line, Michaelis-Menten, Exponential saturation and hyperbolic tangent models for Trifolium subterraneum. The optimum irradiance was found to be at about 1000 µmol m-2 s-1 PAR (Table 3), hence the ETR measurements at irradiances above 1300 µmol m-2 s-1 PAR were omitted from use in fitting the curves shown in this table.

Waiting-in-Line Model / Michaelis-Menten Model / Exponential Saturation Model / Hyperbolic Tangent
k / 0.001101
± 0.0000648 / 383
± 55.9 / 0.002949
± 0.000465 / 0.002398
± 0.0002811
Maximum Photosynthesis (Pmax) / 490 ± 32.4
(ETR µmol mg Chl a-1 h-1)
127 ± 8.10
(µmol O2 mg Chl a-1 h-1) / 684 ± 31.3
(ETR µmol mg Chl a-1 h-1)
171 ± 7.82
(µmol O2 mg Chl a-1 h-1) / 522 ± 32.8
(ETR µmol mg Chl a-1 h-1)
131 ± 8.19
(µmol O2 mg Chl a-1 h-1) / 502 ± 24.6
(ETR µmol mg Chl a-1 h-1)
126 ± 6.16
(µmol O2 mg Chl a-1 h-1)
Optimum light
(µmol m-2 s-1) / 908 ± 53.45 / NA / NA / NA
1/2 Optimum Light
(µmol m-2 s-1) / 211 ± 12.4 / 383 ± 55.9 / 235 ± 37.0 / 229 ± 26.9
Inflection Irradiance
(µmol m-2 s-1) / 1816 ± 107 / NA / NA / NA
Photosynthetic Efficiency (Alpha, ), / ETR = 407.3 ± 36.0 (x 10-6 m2 mg Chl a-1)
O2 = 102 ± 9.00 (x 10-6 m2 mg Chl a-1) / ETR = 496 ± 75.8 (x 10-6 m2 mg Chl a-1)
O2 = 124 ± 19.0 (x 10-6 m2 mg Chl a-1) / ETR = 427.8 ± 72.5 (x 10-6 m2 mg Chl a-1)
O2 = 107 ± 18.1 (x 10-6 m2 mg Chl a-1) / ETR = 334.6 ± 42.5 (x 10-6 m2 mg Chl a-1)
O2 = 83.7 ± 11.8 (x 10-6 m2 mg Chl a-1)
Correlation r (number of samples, data points) / 0.9503
(9,99) / 0.9455
(8,88) / 0.9545
(8,88) / 0.9596
(8,88)

Supplementary Table 3: Comparison of the Light saturation curve parameters fitted to ETR vs. irradiance using the Waiting-in-Line, Michaelis-Menten, Exponential saturation and hyperbolic tangent models for Rhodomonas. The optimum irradiance was found to be at about 40 µmol m-2 s-1 PAR (Table 3), hence the ETR measurements at irradiances above 65 µmol m-2 s-1 PAR were omitted from use in fitting the curves shown in this table.

Waiting-in-Line Model / Michaelis-Menten Model / Exponential Saturation Model / Hyperbolic Tangent
k / 0.0198
± 0.00348 / 12.04
± 3.11 / 0.0704
± 0.0238 / 0.0536
± 0.0146
Maximum Photosynthesis (Pmax) / 73.2 ± 11.5
(ETR µmol mg Chl a-1 h-1)
18.3 ± 2.88
(µmol O2 mg Chl a-1 h-1) / 87.0 ± 7.55
(ETR µmol mg Chl a-1 h-1)
21.8 ± 1.89
(µmol O2 mg Chl a-1 h-1) / 72.6 ± 7.23
(ETR µmol mg Chl a-1 h-1)
18.2 ± 1.81
(µmol O2 mg Chl a-1 h-1) / 70.6 ± 6.04
(ETR µmol mg Chl a-1 h-1)
17.7 ± 1.51
(µmol O2 mg Chl a-1 h-1)
Optimum light
(µmol m-2 s-1) / 50.4 ± 8.84 / NA / NA / NA
1/2 Optimum Light
(µmol m-2 s-1) / 11.7 ± 2.05 / 12.04 ± 3.11 / 9.85 ± 3.33 / 10.2 ± 2.78
Inflection Irradiance
(µmol m-2 s-1) / 101 ± 17.7 / NA / NA / NA
Photosynthetic Efficiency (Alpha, ), / ETR = 110 ± 25.8 (x 10-6 m2 mg Chl a-1)
O2 = 27.4 ± 6.45 (x 10-6 m2 mg Chl a-1) / ETR = 201 ± 54.8 (x 10-6 m2 mg Chl a-1)
O2 = 50.2 ± 13.7 (x 10-6 m2 mg Chl a-1) / ETR = 142 ± 50.0 (x 10-6 m2 mg Chl a-1)
O2 = 35.5 ± 12.5 (x 10-6 m2 mg Chl a-1) / ETR = 105 ± 29.9 (x 10-6 m2 mg Chl a-1)
O2 = 26.3 ± 7.48 (x 10-6 m2 mg Chl a-1)
Correlation r (number of samples, data points) / 0.8613
(16,80) / 0.8666
(16,80) / 0.8661
(16,80) / 0.8641
(16,80)

Supplementary Table 4: Comparison of the Light saturation curve parameters fitted to ETR vs. irradiance using the Waiting-in-Line, Michaelis-Menten, Exponential saturation and hyperbolic tangent models for Phaeodactylum. The optimum irradiance was found to be at about 80 µmol m-2 s-1 PAR (Table 3), hence the ETR measurements at irradiances above 91 µmol m-2 s-1 PAR were omitted from use in fitting the curves.

Waiting-in-Line Model / Michaelis-Menten Model / Exponential Saturation Model / Hyperbolic Tangent
k / 0.0158
± 0.000968 / 16.6
± 2.04 / 0.0533
± 0.00716 / 0.0398
± 0.00424
Maximum Photosynthesis (Pmax) / 173 ± 10.3
(ETR µmol mg Chl a-1 h-1)
43.3 ± 2.58
(µmol O2 mg Chl a-1 h-1) / 206 ± 9.01
(ETR µmol mg Chl a-1 h-1)
51.5 ± 2.25
(µmol O2 mg Chl a-1 h-1) / 171 ± 6.96
(ETR µmol mg Chl a-1 h-1)
42.8 ± 1.74
(µmol O2 mg Chl a-1 h-1) / 168 ± 5.91
(ETR µmol mg Chl a-1 h-1)
42 ± 1.48
(µmol O2 mg Chl a-1 h-1)
Optimum light
(µmol m-2 s-1) / 63.1 ± 3.86 / NA / NA / NA
1/2 Optimum Light
(µmol m-2 s-1) / 14.7 ± 0.896 / 16.6 ± 2.04 / 13.0 ± 1.75 / 13.8 ± 1.47
Inflection Irradiance
(µmol m-2 s-1) / 126 ± 7.72 / NA / NA / NA
Photosynthetic Efficiency ( Alpha, ), / ETR =
207 ± 17.6 (x 10-6 m2 mg Chl a-1)
O2 =
51.7 ± 4.4 (x 10-6 m2 mg Chl a-1) / ETR =
345 ± 45.1 (x 10-6 m2 mg Chl a-1)
O2 =
86.5 ± 11.3 (x 10-6 m2 mg Chl a-1) / ETR =
253 ± 35.5 (x 10-6 m2 mg Chl a-1)
O2 =
63.3 ± 8.88 (x 10-6 m2 mg Chl a-1) / ETR =
186 ± 20.8 (x 10-6 m2 mg Chl a-1)
O2 =
46.4 ± 5.2 (x 10-6 m2 mg Chl a-1)
Correlation r (number of samples, data points) / 0.9669
(16,96) / 0.9557
(16,96) / 0.9621
(16,96) / 0.9634
(9,96)

Supplementary Table 5: Comparison of the Light saturation curve parameters fitted to ETR vs. irradiance using the Waiting-in-Line, Michaelis-Menten, Exponential saturation and hyperbolic tangent models for Acaryochloris. The optimum irradiance was found to be at about 190 µmol m-2 s-1 PAR (Table 3), hence the ETR measurements at irradiances above 221 µmol m-2 s-1 PAR were omitted from use in fitting the curves.

Waiting-in-Line Model / Michaelis-Menten Model / Exponential Saturation Model / Hyperbolic Tangent
k / 0.00554
± 0.000128 / 59.8
± 2.25 / 0.01712
± 0.000615 / 0.0136
± 0.000401
Maximum Photosynthesis (Pmax) / 512 ± 9.68
(ETR µmol mg Chl a-1 h-1)
128 ± 2.42
(µmol O2 mg Chl a-1 h-1) / 670 ± 9.00
(ETR µmol mg Chl a-1 h-1)
168 ± 2.25
(µmol O2 mg Chl a-1 h-1) / 526 ± 7.22
(ETR µmol mg Chl a-1 h-1)
132 ± 1.81
(µmol O2 mg Chl a-1 h-1) / 506 ± 6.10
(ETR µmol mg Chl a-1 h-1)
127 ± 1.53
(µmol O2 mg Chl a-1 h-1)
Optimum light
(µmol m-2 s-1) / 180 ± 4.18 / NA / NA / NA
1/2 Optimum Light
(µmol m-2 s-1) / 41.8 ± 0.969 / 59.8 ± 2.25 / 40.5 ± 1.45 / 40.5 ± 1.20
Inflection Irradiance
(µmol m-2 s-1) / 360 ± 8.36 / NA / NA / NA
Photosynthetic Efficiency ( Alpha, ), / ETR = 214 ± 6.41 (x 10-6 m2 mg Chl a-1)
O2 = 53.6 ± 16.0 (x 10-6 m2 mg Chl a-1) / ETR = 345 ± 45.1 (x 10-6 m2 mg Chl a-1)
O2 = 86.3 ± 11.3 (x 10-6 m2 mg Chl a-1) / ETR = 250 ± 9.62 (x 10-6 m2 mg Chl a-1)
O2 = 62.6 ± 2.41 (x 10-6 m2 mg Chl a-1) / ETR = 191 ± 6.09 (x 10-6 m2 mg Chl a-1)
O2 = 47.7 ± 1.52 (x 10-6 m2 mg Chl a-1)
Correlation r (number of samples, data points) / 0.9962
(16,104) / 0.9940
(16,104) / 0.9968
(16,104) / 0.9964
(16,104)

Ritchie-Supplementary Tables: 1