The researchers studied how photosynthesis in Rhododendron fortunei leaves changes throughout the day. They found that on sunny days, the efficiency of photosynthesis decreases at midday due to strong sunlight. The internal CO2 concentration in the leaves increases at midday, affecting photosynthesis. The highest respiration rate occurs at midday. In shady areas, photosynthesis remains relatively stable throughout the day. The leaves are most efficient at using light in the morning, with efficiency decreasing in the afternoon. Factors like light intensity and temperature directly affect photosynthesis in these leaves.