Abstract:In this research, four Commelinaceae plants (Commelina purpurea, Tradescantia zebrina, Tradescantia flurnuensis ‘Variegata’, and Tradescantia flurnuensis ‘Vairidia’) were used as experimental materials to explore the influence of different light intensities on the growth and photosynthetic characteristics. Shading nets of different densities were used to create five light environments with 100%, 75%, 50%, 25%, and 5% of natural light intensity, respectively. The results indicated that the leaf area, specific leaf area, plant height, and leaf angle of the four plants increased significantly with the decrease of light intensity, but the leaf area of Commelina purpurea was significantly reduced in the 5% natural light intensity. Simultaneously, the reduction of light intensity significantly reduced the upper and lower epidermis and leaf thickness of the four plant leaves, as well as the thickness of the palisade tissue of Commelina purpurea, Tradescantia zebrina and Tradescantia flurnuensis ‘Vairidia’, the thickness of the sponge tissue of Tradescantia zebrina and Tradescantia flurnuensis ‘Vairidia’, but the ratio of palisade and sponge tissue of the four plants did not change significantly. The contents of Chl a, Chl b and Chl (a+b) in Commelina purpurea and Tradescantia zebrina increased first and then decreased with the decrease of light intensity. The contents of Chl a, Chl b and Chl (a+b) in Tradescantia flurnuensis ‘Variegata’ and Tradescantia flurnuensis ‘Vairidia’ increased significantly. Compared with 100% natural light intensity and 5% natural light intensity, the four plants can maintain high stomata opening, net photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate under 25%-75% natural light intensity. In summary, to ensure the normal growth without restriction in low-light environment, the considerable light adaptability of the four Commelinaceae plants can be generated in diverse ways by adjusting the plant morphology, leaf anatomical structure, photosynthetic pigment content, stomata opening and conduction to capture and use light efficiently, maintain a relatively high net photosynthetic rate in low light environments (25%-75% natural light intensity).