SUPLEMENTAÇÃO LUMINOSA NA CULTURA DA SOJA EM SISTEMA DE IRRIGAÇÃO

Light supplementation in soybean cultivation can optimize photosynthesis, promoting vigorous growth and increasing yield. The objective of this study was to evaluate the impacts of light supplementation on the agronomic, physiological, and biochemical parameters of the plant. The experiment was conducted in Cascavel-PR, using three soybean cultivars: BMX Zeus IPRO (C1), BMX Trovão I2X (C2), and BMX Lança IPRO (C3) under controlled light and irrigation conditions. Light supplementation was applied during the V3-V4 to R5-R6 stages of soybean growth, with full-spectrum LED lamps installed in the irrigation pivot. The cultivars did not show significant differences in protein and crude fiber, but variables such as moisture, volatiles, dry matter, ether extract, and mineral residue differed. Zeus IPRO had higher dry matter and mineral residue, Lança IPRO had higher moisture and volatiles, and Trovão I2X had higher ether extract. Cultivar C1 had better performance in germination, initial development, productivity, and weight of 1000 grains, despite having fewer plants per hectare. On the other hand, cultivar C3 had more plants but lower weight of 1000 grains and productivity. Both cultivars surpassed the average productivity of Paraná, indicating that light supplementation combined with irrigation can increase soybean yield.