The Effect of Small Interval Wavelengths Using LEDs on Photosynthetic Rates of Tomato Plants

Light emitting diodes (LEDs) offer great advantages, which include a long lifetime (> 10,000 hr), small size, low thermal output, and adjustable light intensity, over conventional light sources (e.g. incandescent, fluorescent, high pressure sodium). Moreover, LEDs can have very narrow wavelengths (~30 nm) and are easily adjusted for irradiance level. Therefore, these advantages make LEDs perfect for exploring and investigating plant responses to different light conditions including different photoperiods, irradiance or wavelengths while coupling with specific equipment.

The object of this research was to investigate the photosynthetically active radiation (PAR) curve of tomato plant using narrow spectrum LEDs under controlled conditions. The experiment focused on a specific wavelength range (600-700 nm) at a light intensity of 30 and 60 umol m^-2 s^-1 with a small bandwidth ( ~5 nm). The results from this study provide precise information on the impact that specific wavelengths of light have on plant growth and will be used to optimize LED arrays for maximum plant production.