Effects of CO₂ enrichment and different light intensities on the growth of tall fescue seedlings

In this study, to explore the effects of CO₂ concentration and light intensity on the growth and development of tall fescue (Festuca arundinacea) seedlings, we used “Jiaozhan 2” as the experimental object and the phosgene ratio light intensity of 300 μmol·(m²·s)⁻¹ and CO₂ concentration of 400 μmol·mol⁻¹ commonly used in plant factories as the control treatment. Various CO₂ concentrations (atmospheric and enrichment concentrations of 400 and 1 000 μmol·mol⁻¹, respectively) and light intensities low, medium, and high light intensities of 150, 300, and 450 μmol·(m²·s)⁻¹, respectively were implemented to investigate the effects of CO₂ enrichment and light intensity on the growth, physiological characteristics, and appearance quality of tall fescue seedlings. The results indicated that CO₂ enrichment reduced the NDVI and color of tall fescue, resulting in lower appearance quality of turf. However, the treatment of CO₂ enrichment with medium light intensity significantly increased the growth rate of tall fescue and some antioxidant enzyme activities (P < 0.05). It also increased the contents of cellulose and lignin in tall fescue leaves and was more conducive to root and leaf morphology development. The optimal phosgene ratio was determined, comprising a light intensity of 300 μmol·(m²·s)⁻¹ and CO₂ concentration of 1 000 μmol·mol⁻¹, which could provide theoretical parameters for the cultivation of tall fescue in plant factories.