Table I. UVBE (kJ m−2) and PAR (MJ m−2) estimated for every UV treatment and the ambient sunlight.
The UVBE every hour was calculated with four BSWFs: two formulations of Caldwell’s generalized plant action spectrum, GEN(G) given by Green et al. (1974) and GEN(T) given by Thimijan et al. (1978); FLAV (Ibdah et al., 2002) for the accumulation of mesembryanthin in Mesembryanthemum crystallinum; and PG, the new plant growth action spectrum formulated by Flint and Caldwell (2003). Doses weighted with the absorbance spectrum of UVR8 (see Supplemental Fig. S3A in Christie et al., 2012) are also given. All BSWFs were normalized to 1 at a wavelength of 300 nm. Accumulated UVBE and PAR after 12, 36, and 50 h were calculated by summing the corresponding hourly values. In addition, the accumulated nonweighted UV-A and UV-B doses (mmol m−2) in every treatment are reported to allow comparisons with previous research. Ambient (no filter) is not a treatment; these doses were included for comparative purposes.
| UV Treatment | Time | GEN(G) | GEN(T) | FLAV | PG | UVR8 | UV-A | UV-B | PAR |
|---|---|---|---|---|---|---|---|---|---|
| h | |||||||||
| UV 0 | 12 | 0.001 | 0.005 | 0.01 | 0.04 | 0.01 | 122.3 | 0.06 | 6.2 |
| 36 | 0.002 | 0.012 | 0.03 | 0.10 | 0.02 | 328 | 0.15 | 17.2 | |
| 50 | 0.004 | 0.014 | 0.04 | 0.12 | 0.03 | 374.4 | 0.16 | 19.8 | |
| UV A | 12 | 0.01 | 0.46 | 1.8 | 12.7 | 0.56 | 2,395 | 1.1 | 6.6 |
| 36 | 0.03 | 0.91 | 4.6 | 33.2 | 1.40 | 6,323.8 | 2.8 | 18.2 | |
| 50 | 0.04 | 1.02 | 5.1 | 37.7 | 2.12 | 7,195.9 | 3.1 | 21 | |
| UV A+B | 12 | 2.3 | 3.6 | 7.4 | 17.1 | 4.92 | 2,634.2 | 45.2 | 6.4 |
| 36 | 5.6 | 8.8 | 18.3 | 44.3 | 12.05 | 6,934.8 | 109.8 | 17.8 | |
| 50 | 6 | 9.6 | 20.2 | 50 | 18.14 | 7,883.8 | 120.1 | 20.4 | |
| Ambient | 12 | 2.8 | 4.3 | 8.8 | 20.3 | 5.89 | 3,111.1 | 54.1 | 7.4 |
| 36 | 6.7 | 10.5 | 21.8 | 52.5 | 14.42 | 8,189.7 | 131.7 | 20.6 | |
| 50 | 7.2 | 11.5 | 24.1 | 59.2 | 21.72 | 9,310.1 | 143.9 | 23.7 |