Abstract
As the world population continues to grow geometrically, great pressure is being placed on arable land, water and biological resources to provide an adequate supply of food while maintaining the integrity of our ecosystem. However, it is hard to expand the lands suitable for plant raising on the earth. Instead, a number of closed-type plant factories have been constructed to provide steady production of vegetables. To improve food quality by irradiating different LED light wavelength, we investigated changes of visual phenotypes and metabolite profiles of sunny lettuce grown under different LED light conditions. Radiation of red LED light wavelength drastically altered visual phenotypes of sunny lettuce, while samples grown under other light conditions did not change phenotypes in morphology. Multivariate statistical analysis using metabolite profiles of these samples demonstrated that the groups grown under red LED wavelength showed good separation from the others. We investigated significantly changed metabolites by red LED irradiation, there were significant increase in the revels of sugars and phospholipids, while decrease in the levels of amino acids and organic acids.
