LED lighting for indoor cultivation of basil

Indoor cultivation systems are gaining importance worldwide, thanks to their greater efficiency in the use of resources (water, land and nutrients).The limiting factor for these systems is the illumination costs that are still high.In this context, LEDs (light emitting diodes) are gaining attention because of their ability to provide the required light spectra, and high electricity use efficiency.The goal of this study is to identify the role played by red:blue (R:B) ratio on the resource use efficiency of indoor basil cultivation, linking the light physiological response to changes in yield and nutritional properties.Basil plants were cultivated in growth chamber under 5 different R:B ratio LED lighting regimens (respectively, RB0.5, RB1, RB2, RB3, and RB4), using fluorescent lamps as control (CK1).For the six light treatments, a PPFD of 215 mol m -2 s -1 and a photoperiod of 16/8 light/dark per day were provided.Greater biomass production was associated with LEDs lighting as compared with fluorescent lamp, with best performances observed using RB≥2.Adoption of RB2 and RB3 improved also the plant's capacity to transform resources, resulting in greatest water, land and energy use efficiency.Nutrient use efficiency was increased by using LED lights with a greater portion of blue light in the spectrum.Decreasing R:B ratio also increased leaf stomatal conductance.Plant grown under RB3 showed the best antioxidant properties in terms of flavonoid content and FRAP as compared to the other light treatments.From this study it can be concluded that a R:B ratio of 3 (RB3) provides optimal growing conditions for indoor cultivation of basil.