Tomato Seedling Response to Light Spectral Composition

The experiment was conducted to solve a gap in the knowledge due to the lack of studies on the effect of different maturities of tomato hybrids (very early, early, medium, and medium late) on diverse light treatments of monochromatic and dual light. The work was done within the artificial climate laboratory (RSAU – MTAA). Seven light treatments (red, green, blue, and white), four hybrids (Captain F1, Rafinad F1, Coral Reef F1, and Fire F1), and dual light treatments (green+blue, blue+red, and green+red) using a factorial experiment with two factors (radiation, factor B, and hybrids, factor A) based on randomized complete block design in four repetitions were used. Plants irradiated with white light increased photosynthesis (3.13µmolm2s-1), and radiation with dual light (blue+red) provided the best stem diameter (6.16 mm). Plants exposed to green and blue radiation exhibited the highest fresh weight leaves and roots (11.20 g plant-1and 30.08g plant-1 respectively), and plants treated with green and red light showed the highest fresh weight of stems (7.85g plant-1). As a result, monochromatic red-light radiation increased the number and total area of leaves. While dual radiation contributed to the increased relative chlorophyll content of leaves. Different light spectra had an effect on tomato seedling growth.