Agronomy (May 2021)
Growth Stage Specific Lighting Spectra Affect Photosynthetic Performance, Growth and Mineral Element Contents in Tomato
Abstract
The aim of study was to evaluate if the alternation in growth stage–specific lighting spectrum would be superior for tomato growth, photosynthesis, and mineral element contents compared to constant spectrum lighting. Dwarf tomato (Solanum lycopersicum L. cv. Micro Tom) was cultivated in controlled environment chamber (23/19 °C) under light emitting diode lighting. Three lighting spectrum treatments were set, optimized for different tomato growth stages: “seedling” (S; blue (B, 447 nm), red (R, 660 nm) and far red (FR, 740 nm) light), “growth” (G; R, B and FR light, supplemented with 523 nm green) and fruiting (F; R, B, FR light supplemented with 385 nm ultraviolet A (UV-A)). The total photon flux density of 250 μmol m−2·s−1 was maintained in all treatments. Three lighting spectrums were alternated in seedling (S, G, F), biomass growth (SS, SG, GG, FF) and fruiting (SSS, SGG, GGG, GGF, FFF, SGF) stages of tomato creating growth stage-specific or constant lighting spectrum strategies. The light effects depended on tomato age, however the alternation in growth stage-specific lighting spectrum did not have a pronounced impact on dwarf tomato photosynthetic indices, growth, yield and mineral element content. The investigated parameters mainly depended on the spectrum of the latter growth stage.
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