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The technique of greenhouse stereoscopic seedling nursing in rice seedlings has many benefits, such as achieving the efficient use of seedling land and promoting standard centralized rice seedling. However, since multiple layers of seedbeds are stacked together and block light from each other, the problem of insufficient lighting arises from greenhouse stereoscopic nursing. Therefore, artificial supplemental lighting technology needs to be applied in the greenhouse in order to improve the illumination conditions of the seedbed layers, thus to enhance the quality of rice seedlings. In this paper, the range of flux ratio of red to blue light required for rice seedlings growth optimally was determined based on fundamental findings of the plant optical theoretical analysis; the light intensity distribution inside the greenhouse was calculated based on the theory of illumination analysis; and the light environment among the layers of seedbeds inside the greenhouse was simulated using the Ecotect software. Simulation results showed that, without artificial supplemental lighting, except the top layer, the light intensity on each seedbed layer couldn't meet the requirements of the rice seedlings growth. Based on the theoretical analysis and simulation results, the effects of different artificial lighting conditions on the growth quality of rice seedling were studied. In the study, LED plant lights were adopted to provide supplemental lighting to all seedbed layers except the top layer, and orthogonal experimental design was implemented to study the effects of the flux ratio of red to blue light, the light intensity and the frame spacing among the seedbed layers on rice seedlings quality. Experimental results from this study showed that the lighting condition with a flux ratio of red to blue light of 10:1 and a light intensity of 2 500 lx was beneficial to promoting rice stem elongation and growth; the lighting condition with a flux ratio of red to blue light of 8:1 was beneficial to retaining dry matters in rice seedlings and ensuring the tangle of the roots; and the rice seedlings processed by the lighting with a flux ratio of red to blue light of 8:1 had a higher healthy index compared to the rice seedlings processed by the lighting with a flux ratio of red to blue light of 6:1 or 10:1. The analysis of this study showed that the order of significance of the aforementioned 3 factors' effects on the quality of rice seedlings was: flux ratio of red to blue light>light intensity>frame spacing. The best artificial lighting condition was shown to be with a flux ratio of red to blue light of 8:1, a light intensity of 2 500 lx and a frame spacing of 45 cm. The conclusions of this study may serve as a technical reference for industrialized stereoscopic rice seedlings applications and provide guidance to the greenhouse stereoscopic rice seedling nursing. [ABSTRACT FROM AUTHOR]