Flavone extract from C.cathayensis Exocarp can boost photosynthesis in corn, soybean, wheat, and mung bean seedlings. At concentrations of 0.1 to 0.5mg·L-1, it increases chlorophyll levels, photosynthetic rate, and CO2 intake, leading to better leaf efficiency. However, higher concentrations can have the opposite effect, decreasing chlorophyll and photosynthesis while increasing CO2 levels. The ideal concentration is 0.1mg·L-1, showing significant improvements in chlorophyll content and photosynthetic rate.