Influence of Pulsed, Scanning and Constant (16- and 24-h) Modes of LED Irradiation on the Physiological, Biochemical and Morphometric Parameters of Lettuce Plants (Lactuca sativa L.) while Cultivated in Vertical Farms

In city farming, when growing green crops, a significant part of the production cost is electricity for lighting. The physiology, biochemistry, morphology and productivity plants can be affected by changing irradiation modes these changes reduce costs. However, results studies in literature are contradictory. this work, we investigated effect impulse (frequency 1000 Hz duty cycle 67%), scanning (the principle running lights) constant 16 h 24 operation white light LED irradiators on physiological, biochemical morphometric parameters lettuce with red leaves. daytime integral all variants remained unchanged ~15.6 mol m−2 day−1. Daily consumption also did not differ significantly. Plants were grown racks climatic chamber up to 35 days age. For leaves, most optimal biomass accumulation synthesis anthocyanins was illumination mode, while no statistically differences observed under different modes. red-leaved lettuce, it found that highest concentration carotenoids leaf (24 h) irradiation, which associated more active reaction photosynthetic system prolonged increased intensity during irradiation. Also, activity both varieties at irradiators, which, however, affect their final productivity. may useful development illuminators use rack growing.