| Popis: |
As microgreens are increasingly grown as functional food, their cultivation technologies require optimization of factors such as temperature, light and humidity. Quality (wavelength) and photoperiod (duration) are the most important light factors that directly affect yield and morphological properties of plants. Photosynthetically active radiation (PAR) includes wavelengths in the range of 400-800 nm, whereby specific photoreceptors of plant cells absorb blue (400-500 nm), red (600-700 nm) and dark red (700-800 nm) wavelengths. The aim of this research was to determine the effect of supplemental LED's lighting with blue (450 nm), red (620 nm) and combination of blue and red spectrum (50:50) in the photoperiod of 14 h on the yield, morphological properties, pigments and colour content of broccoli microgreens. The research was conducted in a climate chamber with controlled conditions for plant cultivation (25 °C, 60% relative air humidity). Samples of broccoli microgreens were manually cut at the base of the hypocotyl in the cotyledon phenophase at a height of 7.5 cm after eight days. Microgreens of broccoli grown under LED supplementary lighting of blue spectrum and combination of blue and red spectrum showed higher yields (1198 g/m2) than samples grown under red spectrum (1046 g/m2). Broccoli microgreens grown under red spectrum had a longer hypocotil (69.7 mm) than samples grown under blue and combined spectrum. Samples grown under blue light treatment had larger leaf lenght (9 mm) than samples grown under red light treatment and combined light treatment. Most clorophylls were acumulated under blue light (0.920 mg/l) as well as carotenoids (0.410 mg/l) and most colors were accumulated under combined light. Based on the results, it can be emphasised that growing microgreens under supplemental lighting (LED) has a positive effect on morphological parameters, yield and pigment content. |
