Plants' responds to exposure of different lighting conditions
Securing food for a growing world population, loss of fertile soils by urbanization, erosion and desertification and change of precipitation patterns due to climate change and negative impacts of conventional agriculture-these are the factors making it inevitable to develop new concepts for a resource efficient food production. Moreover urban horticultural systems can contribute to enhance the supply of urban inhabitants with high quality products. Especially fresh vegetables as tomatoes or cucumbers are grown hydroponically in protected horticultures already in significant rates where soil-independent water-based systems are used to ensure the supply of much of the vegetables. The site conditions are only linked to light, water, heat and nutrient availability. These four factors can be found without any difficulties in urban areas. By integrating food production into new or existing building technologies (inFARMING®) synergies of the greenhouse and the original building can be used effectively. As part of our work we will present new results of demonstration plant experiments for intelligent grow light systems. Regarding new requirements in indoor farming applications growth conditions of plants concerning concentrations of the active ingredients can be regulated among others by adapting the light spectrum. The technology is demonstrated by the example of lovage and the light-optimized production of the flavonoids formed by the plants. Furthermore the presented work will show new basic approaches to permit a nondestructive optical analysis method. Main results In green plants chlorophyll (a) and (b) are mainly responsible for the absorption of light. This needed spectrum is generated by LED. The content of flavonoids in the plant biomass which formation is induced by different light spectra and light intensities was measured by using our established HPLC-method. In addition to that first results of a nondestructive optical analysis method based on fluorescence are introduced.