Effects of different light qualities on seedlings growth and substance accumulation of Cinnamomum camphora

<bold>Objective</bold> The study aims to investigate the effects of different light qualities（red light and blue light）on the growth characteristics，morphologenesis，and substance accumulation of <italic>Cinnamomum camphora</italic> seedlings，providing a theoretical basis for the industrialized production of high-quality seedlings of <italic>C. camphora</italic>. <bold>Method</bold> Shoots of <italic>C. camphora</italic>（M8），a superior single tree clone，were used as the research object.White light（WL）was used as the control group，while red light（RL）and blue light（BL）were applied to explore the effects of different light qualities on the growth of <italic>C. camphora</italic> seedlings.The experiment lasted for 60 days，during which the growth indices，root morphological traits，and substance accumulation of the seedlings were measured and analyzed. <bold>Result</bold> Compared with white light treatment，red light significantly promoted the growth of seedling height and internode length，while blue light significantly increased leaf thickness.Both red and blue light treatments significantly increased the biomass and non-structural carbohydrates accumulation of <italic>C. camphora</italic> seedlings，and altered the biomass allocation ratio.Red light significantly promoted stem biomass allocation and blue light increasing root biomass allocation.Blue light significantly promoted root development，resulting in significantly higher root surface area and root volume compared to other treatments.In terms of photosynthetic pigments，there was no significant difference（<italic>P</italic>＞0.05）in the contents of Chlorophyll a，chlorophyll b，total chlorophyll，and carotenoids among white light，red light，and blue light treatments.However，blue light significantly increase anthocyanin concentration.The analysis of cellulose and lignin showed that red light significantly reduced the concentrations of cellulose and hemicellulose in the stems of seedlings，while blue light significantly increased the concentrations of lignin and cellulose but decreased the concentration of hemicellulose.The analysis of volatile substances revealed that red light had no significant effect on the volatile substances of <italic>C. camphora</italic> seedlings leaves，while blue light significantly increased the concentrations of β-caryophyllene，α-caryophyllene，and trans-nerolidol，but decreased the concentrations of limonen-6-ol pivalate，acetylcedrene，phylloquinone，and 6-O-palmitoyl-L-ascorbic acid. <bold>Conclusion</bold> Different light qualities have significant effects on the growth characteristics and physiological indices of <italic>C. camphora</italic> seedlings.Blue light not only promotes root development but also significantly alters the concentration of secondary metabolites in the leaves of <italic>C. camphora</italic> seedlings，providing a theoretical basis for the industrialized propagation of <italic>C. camphora</italic> seedlings.