Influence of artificial light spectral quality for enhancing growth, nutrient uptake and resource use efficiency of pak choi cv. Choko in indoor agriculture

Global challenges including population growth, urbanization, resource scarcity and climate change demand transformative innovations in indoor agriculture to enhance resource efficiency and ensure sustainable crop production. The present study evaluates the impact of artificial light spectral treatments on the growth, nutrient uptake and resource use efficiency (RUE) of pak choi (Brassica rapa var. chinensis) in a controlled multi-tier indoor cultivation system. Four light treatments were tested including white + red and blue (W+RB), red and blue (RB), white + blue (W + B) and control (white LED). W+RB significantly improved plant height (21.17 cm), leaf area (471.79 cm²), NDVI and biomass. Enhanced root architecture under W+RB correlated with increased nutrient uptake of nitrogen, phosphorus, potassium, calcium, zinc and iron, underscoring the synergy between root development and nutrient absorption. Additionally, W+RB demonstrated superior resource efficiency, achieving an electrical energy use efficiency of 0.15, water-use efficiency of 77.01 g FW L⁻¹ and light-use efficiency of 0.41 g DW mol⁻². These findings highlight W+RB’s potential to boost productivity and sustainability in indoor agriculture. Future research should scale its application across crops, integrate renewable energy solutions and further enhance resource efficiency to address global food security challenges sustainably.