TABLE 1 Fluorescent material (parts by mass) Photon flux Ratio of First fluorescent Second fluorescent density photon Fresh weight Nitrate nitrogen material material (μmol · m−2 · s−1) flux densities (Edible part) content (MGF/CASN = 95:5) (YAG: Ce, Cr) B R FR R/B R/FR (g) (mg/100 g) Comparative 35.5 88.8 0.0 2.5 26.2 361.2 Example 1 Example 1 60 31.5 74.9 12.6 2.4 6.0 35.4 430.8 Example 2 50 10 28.5 67.1 21.7 2.4 3.1 34.0 450.0 Example 3 40 20 25.8 62.0 28.7 2.4 2.2 33.8 452.4 Example 4 30 30 26.8 54.7 33.5 2.0 1.6 33.8 345.0 Example 5 25 39 23.4 52.8 38.1 2.3 1.4 28.8 307.2