The relation between temperature and radiation is quite straight. In case of low radiation and a high temperature, net energy of the plant for growth is low, plants strech, smaller fruits, taste worser.
In case of high radiation, low temperatures, crops may become dark green, growth speed is too low.
For calculating the total LDI:
– capacity LED (umol/m2) x 0,0036 = LED mol/m2/hour
LED mol/m2/hour x hours active = LED mol/m2/day
– radsum x 0,0153 = Sunlight mol/m2/day (indication!)
-LDI = LED mol/m2/day + Sunlight mol/m2/day
Below a table with the optimum relation between radiation and 24-hour temperature.
| 24-hour oC | 24-hour oC | 24-hour oC | ||
| Radsum | PAR LDI | growth | growth | growth |
| J/cm2/day | Mol/m2/day | ( normal) | ( forcing ) | ( slow ) |
| 50 | 0,8 | 11,5 | 11,5 | 11,5 |
| 100 | 1,5 | 12,0 | 12,0 | 12,0 |
| 150 | 2,3 | 12,5 | 12,5 | 12,5 |
| 200 | 3,1 | 13,0 | 13,0 | 13,0 |
| 450 | 6,9 | 13,6 | 14,0 | 13,3 |
| 700 | 10,8 | 14,3 | 15,0 | 13,5 |
| 950 | 14,6 | 14,9 | 16,0 | 13,8 |
| 1200 | 18,5 | 15,5 | 17,0 | 14,0 |
| 1450 | 22,3 | 16,1 | 18,0 | 14,3 |
| 1700 | 26,2 | 16,8 | 19,0 | 14,5 |
| 1950 | 30,0 | 17,4 | 20,0 | 14,8 |
| 2200 | 33,8 | 18,0 | 21,0 | 15,0 |
