Different poplar cultivars respond differently to variations in leaf colour in terms of photosynthetic activity. This study aims to compare the photosynthetic abilities of a green leaf (L2025) and a red leaf (ZHP) cultivar of Populus deltoides. In this investigation, "ZHP" demonstrated broad ranges, enormous potential, and CO2 concentration consumption that were similar to those in "L2025" and even shown a better absorption for weak light.

The net photosynthetic rate (Pn) in "ZHP" was significantly lower than that in "L2025" under high light or high CO2 conditions, which was primarily attributed to stomatal regulation and different photosynthetic efficiency (including the light energy utilisation efficiency and photosynthetic CO2 assimilation efficiency) in the "L2025" and "ZHP" samples. However, with increasing light intensity and CO2 concentration, the photosynthetic capacity in both "L2025".

Colored leaf plants have been widely used in road greening, courtyard decoration, and garden edging as the social economy has developed quickly. The many methods of leaf coloration, however, significantly alter the physiological and biochemical adaptabilities in plants, particularly the photosynthesis, which is frequently decreased in coloured leaf plants to fulfil specific ecological objectives, such as mimic defence and pollination.

The low photosynthetic capacity of colourful leaf plants limits their growth and development, and the restriction will be exacerbated under adversity stress, which is thought to be a significant problem, restricting their widespread promotion and use. Although there is little known about the photosynthetic mechanisms for "ZHP," leaf pigment compositions may have an impact on the plant's ability to photosynthesise. Previous research have also discovered scant evidence of light reaction stages and molecular levels.