The impact of spectral composition of white LEDs on spinach (Spinacia oleracea) growth and development
LED is a promising light source for the cultivation of edible vegetables in greenhouses. The spectral radiation of the light sources has an impact on plants physiological parameters as well as on morphological features . In this study the growth of spinach plants has been carried out in experimental boxes under two white LED treatments having different CCT (CL = 6500 K, WL = 3000 K) with the aim of investigating the influence of the two light spectra on plant development and comparing the results. Results show that the different lighting treatment impacts on leaf area, stem diameter, vigour of roots and chlorophyll content but not on petiole elongation and roots length; a more rapid and better growth was obtained with the cold LED compared to the warm LED, while a higher number of new leaves and chlorophyll concentration level were found under warm LED.