Table 1.
Agronomic characteristics of ‘Levistro’ lettuce plants grown hydroponically under ambient light enriched with different LED light spectra.
| Treatments | DLI 1 | PAR 2 | Fresh Weight | Dried Weight | Leaf Number | ||
|---|---|---|---|---|---|---|---|
| Light | Spectrum | R:B Ratio 3 | mol m−2 day−1 | µmoles m−2 s−1 | g plant−1 | % | plant−1 |
| Blue (B) | 47:22:21:10 | 0.5:1 | 9.4 ± 1.1 | 331 ± 26 | 35.6 ± 3.3 a 4 | 9.1 ± 0.2 a | 14.7 ± 0.6 b |
| White (W) | 30:38:23:9 | 0.8:1 | 9.1 ± 1.0 | 330 ± 25 | 38.3 ± 5.9 a | 9.2 ± 0.4 a | 15.3 ± 1.2 ab |
| Blue-Red (BR) | 33:15:44:8 | 1.3:1 | 9.5 ± 1.1 | 336 ± 20 | 41.4 ± 3.4 a | 9.0 ± 0.6 a | 16.7 ± 1.0 a |
| Red (R) | 16:16:60:8 | 3.8:1 | 9.6 ± 1.1 | 328 ± 24 | 40.6 ± 7.1 a | 9.8 ± 0.7 a | 16.4 ± 0.7 a |
| Control 5 | 25:30:31:14 | 1.2:1 | 16.9 ± 1.9 | 702 ± 126 | 40.6 ± 7.0 a | 9.1 ± 0.3 a | 16.2 ± 0.8 ab |
1 Daily light integral; 2 photosynthetically active radiation measured at midday; 3 red:blue ratio; 4 different letters in the same column indicate significant differences using Tukey’s test (p ≤ 0.05). Mean (n = 3) ± SE; 5 ambient light.