Fig. 23: Cumulative total yield of tomatoes in kg

4.3 Yield

4.3.1 Total yield of fruits

The yield of tomatoes included all harvested red fruits during the growth period. The fruits were classified in 1. class (> 55 mm), 2. class (45-55 mm) and not marketable fruits (too little fruits (< 45 mm), fruits with blossom end rot, not well shaped fruits and green fruits at the end of the harvest period).

Cumulative total yield of tomatoes ranged between 27-32 kg/m2 (Fig. 23). In total the cumulative total yield of tomatoes was independent of the light treatment (“HPS” versus “Hybrid”), but significantly lower when lights were mounted higher. However, the 1. class yield and the 2. class yield was affected by the light treatment. Under “Hybrid high” significantly lower 1. class yield was measured than under “Hybrid”, whereas the 2. class yield was independent of the height of the lights. A significantly higher 2. class yield was measured under “HPS” compared to “Hybrid”. In contrast, the too little fruits as well as the green fruits were neither affected by the light source nor by the height of the lights.

Fig. 23: Cumulative total yield of tomatoes in kg.

Letters indicate significant differences at the end of the experiment (HSD, p ≤ 0,05).